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Sample records for 36cl production rate

  1. Atmospheric production rate of {sup 36}Cl

    Energy Technology Data Exchange (ETDEWEB)

    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. Production rates of 36Cl in basalts from the calibration site of Fuerteventura, Canary Islands

    NARCIS (Netherlands)

    Mai, K.

    2009-01-01

    Age determination based on cosmogenic nuclides is an important tool to investigate landscape development and age relations of geologically very young materials. The aim of this study is to contribute data to establish age determination of the basis of cosmogenic 36Cl production as a generally reliab

  3. Measuring astrophysically relevant 36Cl production cross sections

    Science.gov (United States)

    Anderson, Tyler; Skulski, Michael; Ostdiek, Karen; Lu, Wenting; Clark, Adam; Nelson, Austin; Beard, Mary; Collon, Philippe

    2016-09-01

    The short-lived radionuclide 36Cl (t1 / 2 = 0 . 301 Ma) is known to have existed in the Early Solar System (ESS), and evaluating its production sources can lead to better understanding of the processes taking place in ESS formation and their timescales. The X-wind model is used to explain 36Cl production via solar energetic particles from the young Sun, but is lacking empirical data for many relevant reactions. Bowers et al. (2013) measured the 33S(α,p)36Cl cross section at various energies in the range of 0.70-2.42 MeV/A, and found them to be systematically under predicted by Hauser-Feshbach statistical model codes TALYS and NON-SMOKER, highlighting the need for more empirical data for these cross sections. Recent results of the re-measurement of the 33S(α,p)36Cl reaction, providing greater coverage of the same energy range as Bowers et al., will be presented. Future plans for measurement of other 36Cl producing reactions will also be discussed.

  4. Measurement of the 33S(\\alpha,p)36Cl cross section: Implications for production of 36Cl in the early Solar System

    CERN Document Server

    Bowers, Matthew; Bauder, William; Beard, Mary; Collon, Philippe; Lu, Wenting; Ostdiek, Karen; Robertson, Daniel

    2013-01-01

    Short-lived radionuclides (SLRs) with lifetimes \\tau < 100 Ma are known to have been extant when the Solar System formed over 4.5 billion years ago. Identifying the sources of SLRs is important for understanding the timescales of Solar System formation and processes that occurred early in its history. Extinct 36Cl (t_1/2 = 0.301 Ma) is thought to have been produced by interaction of solar energetic particles (SEPs), emitted by the young Sun, with gas and dust in the nascent Solar System. However, models that calculate SLR production in the early Solar System (ESS) lack experimental data for the 36Cl production reactions. We present here the first measurement of the cross section of one of the main 36Cl production reactions, 33S(\\alpha,p)36Cl, in the energy range 0.70 - 2.42 MeV/A. The cross section measurement was performed by bombarding a target and collecting the recoiled 36Cl atoms produced in the reaction, chemically processing the samples, and measuring the 36Cl/Cl ratio of the activated samples with ...

  5. Study of Rock's Erosion Rate Based on the Determination of 36Cl by AMS

    Institute of Scientific and Technical Information of China (English)

    WANGYue; WUShao-yong; GUANYong-jing; LIUCun-fu; WUWei-ming; JIANGShan

    2003-01-01

    It is very important for science and economy to study the erosion rate of geology. The advanced technology and method may be extended to study the flourishing of the earth's crust and date. Since the measurement of cosmogenic nuclide became reality by AMS, the cosmogenic nuclide becomes more important in geoscience. So the determination of rock's erosion rate with 36Cl by AMS was going on.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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.

  8. Measurement of the 33S(\\alpha,p)36Cl cross section: Implications for production of 36Cl in the early Solar System

    OpenAIRE

    Bowers, Matthew; Kashiv, Yoav; Bauder, William; Beard, Mary; Collon, Philippe; Lu, Wenting; Ostdiek, Karen; Robertson, Daniel

    2013-01-01

    Short-lived radionuclides (SLRs) with lifetimes \\tau < 100 Ma are known to have been extant when the Solar System formed over 4.5 billion years ago. Identifying the sources of SLRs is important for understanding the timescales of Solar System formation and processes that occurred early in its history. Extinct 36Cl (t_1/2 = 0.301 Ma) is thought to have been produced by interaction of solar energetic particles (SEPs), emitted by the young Sun, with gas and dust in the nascent Solar System. Howe...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Parrat, Y. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    The concentrations of the cosmogenic radionuclide {sup 32}Si 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 {sup 32}Si concentrations in environmental samples in contrast to conventional radiometric detection. The measured {sup 32}Si concentrations in the snow samples were between 1.84 and 6.28 {mu}Bql{sup -1}. These values agree with other measurements of precipitation samples. The measured {sup 32}Si/Si{sub tot} ratios ranged from 2.5.10{sup -17} to 2.3.10{sup -15} and were thus below the present detection limit of about 10{sup -14}, showing that at present it is not possible to carry out AMS measurements of {sup 32}Si in precipitation samples. For the first time, experimental cross sections of the reaction {sup 40}Ar(p,X){sup 36}Cl 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){sup 7}Be and N(p,X){sup 10}Be 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 {sup 40}Ar(p,X){sup 36}Cl exhibits two maxima at proton energies of 20 MeV for the (p,{alpha}n)reaction and 95 MeV for the (p,2p3n) reaction, with maximum cross sections of 105 mb and 53 mb, respectively. (author) figs., tabs., refs.

  11. New dating method: Groundwater residence time estimated from the 4He accumulation rate calibrated by using cosmogenic and subsurface-produced 36Cl

    Directory of Open Access Journals (Sweden)

    Habermehl M. A.

    2012-04-01

    Full Text Available Groundwater contains dissolved He, and its concentration increases with the residence time of the groundwater. Thus, if the 4He accumulation rate is constant, the dissolved 4He concentration in ground-water is equivalent to the residence time. Since accumulation mechanisms are not easily separated in the field, we estimate the total He accumulation rate during the half-life of 36Cl (3.01 × 105 years. We estimated the 4He accumulation rate, calibrated using both cosmogenic and subsurface-produced 36Cl, in the Great Artesian Basin (GAB, Australia, and the subsurface-produced 36Cl increase at the Äspö Hard Rock Laboratory, Sweden. 4He accumulation rates range from (1.9±0.3 × 10−11 to (15±6 × 10−11 ccSTP·cm−3·y−1 in GAB and (1.8 ±0.7 × 10−8 ccSTP·cm−3·y−1 at Äspö. We confirmed a ground-water flow with a residence time of 0.7-1.06 Ma in GAB and stagnant groundwater with the long residence time of 4.5 Ma at Äspö. Therefore, the groundwater residence time can be deduced from the dissolved 4He concentration and the 4He accumulation rate calibrated by 36Cl, provided that 4He accumulation, groundwater flow, and other geo-environmental conditions have remained unchanged for the required amount of geological time.

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

    CERN Document Server

    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...

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

    Science.gov (United States)

    Poluianov, S. V.; Kovaltsov, G. A.; Mishev, A. L.; Usoskin, I. G.

    2016-07-01

    New consistent and precise computations of the production of five cosmogenic radioisotopes, 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 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 radioisotopes, etc. As an example, computations of the 10Be deposition flux in the polar region are shown for the last decades and also for a period around 780 A.D. and confronted with the actual measurements in Greenland and Antarctic ice cores.

  14. Production of the cosmogenic isotopes 3H, 7Be, 10Be, and 36Cl in the Earth's atmosphere by solar and galactic cosmic rays

    Science.gov (United States)

    Webber, W. R.; Higbie, P. R.; McCracken, K. G.

    2007-10-01

    In a follow-up study to the earlier work of Webber and Higbie (2003) on 10Be production in the Earth's atmosphere by cosmic rays, we have calculated the atmospheric production of the cosmogenic isotopes 3H, 7Be, 10Be, and 36Cl using the FLUKA Monte Carlo code. This new calculation of atmospheric yields of these isotopes is based on 107 vertically incident protons at each of 24 logarithmically spaced energies from 10 MeV to 10 GeV, 102 times the number used in the earlier calculation, along with the latest cross sections. This permits a study of the production due to solar cosmic rays as well as galactic cosmic rays at lower energies where isotope production is a very sensitive function of energy. Solar cosmic ray spectra are reevaluated for all of the major events occurring since 1956. In terms of yearly production of 10Be, only the February 1956 solar event makes a major contribution. For 36Cl these yearly SCR production contributions are 2-5 times larger depending on the solar cosmic ray energy spectra. We have determined the yearly production of 10Be, 36Cl, and other cosmogenic isotopes above 65° geomagnetic latitude for the time period 1940-2006 covering six solar 11-year (a) cycles. The average peak-to-peak 11-a amplitude of this yearly production is 1.77. The effects of latitudinal mixing alter these direct polar production values considerably, giving an average peak-to-peak 11-a amplitude of 1.48 for the global average production.

  15. 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.

    Science.gov (United States)

    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

  16. 36Cl bomb peak: comparison of modeled and measured data

    Directory of Open Access Journals (Sweden)

    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.

  17. 36Cl bomb peak: comparison of modeled and measured data

    Directory of Open Access Journals (Sweden)

    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.

  18. Performance of the modified DREAMS ion source for {sup 36}Cl applications

    Energy Technology Data Exchange (ETDEWEB)

    Pavetich, Stefan; Akhmadaliev, Shavkat; Merchel, Silke; Rugel, Georg; Ziegenruecker, Rene [Helmholtz-Zentrum Dresden-Rossendorf (Germany)

    2014-07-01

    First analyses of real {sup 36}Cl-AMS samples were performed with the newly developed low memory-effect ion source at the DREsden Accelerator Mass Spectrometry (DREAMS) facility. Considerable improvements have been reached with respect to the overall ion source performance. Especially, parameters like current output, ion source fractionation effects, normalization factors, blank values and sulphur suppression factors have been investigated to enhance accuracy of {sup 36}Cl-data. Applications cover a wide spectrum, which implies also highly variable {sup 36}Cl/{sup 35+37}Cl-ratios ranging from nearly background level of ∝10{sup -15} up to 10{sup -10}. Samples from aquifers in arid regions for groundwater dating and modelling were analysed. Meteorite samples were measured to investigate the constancy of the galactic cosmic radiation, production rates from sulphur, and reconstruction of exposure histories of individual meteorites.

  19. Problems of contamination in 36Cl studies

    Science.gov (United States)

    Bird, J. R.; Shahgholi, N.; Jenkinson, A.; Smith, A.; Fifield, L. K.; Ophel, T.; Allan, G.

    1990-12-01

    The joint ANSTO/ANU 36Cl program has now measured more than 700 samples from many different locations. During the course of this work, a variety of contamination problems have affected a small number of results which have provided valuable information on the effects of ion source cross-talk, sample preparation and storage procedures and sources of high- 36Cl material. A sample of Weeks Island halite is processed along with every batch of field samples and the observed ratio provides a clear distinction between normal batches and those subject to contamination. Over three years, the long-term average ratio of {36Cl}/{Cl} for normal halite samples is (1 ± 1) × 10 -15. The sample handling procedures developed during the course of this work provide a useful guide to the techniques that must be used to achieve the sensitivity limits which are potentially available using AMS.

  20. Cross-sections for 36Cl from Ti at E p=35-150 MeV: Applications to in-situ exposure dating

    Science.gov (United States)

    Fink, David; Vogt, Stephan; Hotchkis, Michael

    2000-10-01

    We have measured the low-energy yield of 36Cl from Ti for proton energies from 35 to 150 MeV. Thin Ti foil irradiations were performed at the Harvard University Cyclotron Laboratory and 36Cl concentrations were determined using the ANTARES AMS facility at ANSTO. Cross-sections ranged smoothly with energy from 0.32±0.05 mb at 35 MeV to 5.3±0.4 mb at 150 MeV. Results for E<110 MeV are new, while the upper region from 110 to 150 MeV agrees well with overlapping data from other studies. The in-situ production rate for 36Cl from Ti at the earth's surface and high latitude based on this excitation function and calculations of Masarik and Reedy (normalised to the mean measured yield of 36Cl from Ca) is estimated at ˜(13±3) atoms 36Cl (g Ti yr) -1. We thus conclude that in Ti-rich, Ca-poor rocks or in typical basalts, 36Cl yield from Ti can amount to ˜5-10% of total. This is similar to the contribution from slow muon capture on 40Ca and in some cases, from thermal neutron capture on native Cl.

  1. A comparison of groundwater dating with 81Kr, 36Cl and 4He in four wells of the Great Artesian Basin, Australia

    Science.gov (United States)

    Lehmann, B. E.; Love, A.; Purtschert, R.; Collon, P.; Loosli, H. H.; Kutschera, W.; Beyerle, U.; Aeschbach-Hertig, W.; Kipfer, R.; Frape, S. K.; Herczeg, A.; Moran, J.; Tolstikhin, I. N.; Gröning, M.

    2003-06-01

    The isotopic ratios 81Kr/Kr and 36Cl/Cl and the 4He concentrations measured in groundwater from four artesian wells in the western part of the Great Artesian Basin (GAB) in Australia are discussed. Based on radioactive decay along a water flow path the 81Kr/Kr ratios are directly converted to groundwater residence times. Results are in a range of 225-400 kyr with error bars in the order of 15% primarily due to counting statistics in the cyclotron accelerator mass spectrometer measurement. Additional uncertainties from subsurface production and/or exchange with stagnant porewaters in the confining shales appear to be of the same order of magnitude. These 81Kr ages are then used to calibrate the 36Cl and the 4He dating methods. Based on elemental analyses of rock samples from the sandstone aquifer as well as from the confining Bulldog shale the in situ flux of thermal neutrons and the corresponding 3He/ 4He and 36Cl/Cl ratios are calculated. From a comparison of: (i) the 3He/ 4He ratios measured in the groundwater samples with the calculated in situ ratios in rocks and (ii) the measured δ 37Cl ratios with the 4He concentrations measured in groundwater it is concluded that both helium and chloride are most likely added to the aquifer from sources in the stagnant porewaters of the confining shale by diffusion and/or mixing. Based on this 'working hypothesis' the 36Cl transport equation in groundwater is solved taking into account: (i) radioactive decay, (ii) subsurface production in the sandstone aquifer (with an in situ 36Cl/Cl ratio of 6×10 -15) and (iii) addition of chloride from a source in the confining shale (with a 36Cl/Cl ratio of 13×10 -15). Lacking better information it is assumed that the chloride concentration increased linearly with time from an (unknown) initial value Ci to its measured present value C= Ci+ Ca, where Ca represents the (unknown) amount of chloride added from subsurface sources. Using the 81Kr ages of the four groundwater samples and a

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

    Science.gov (United States)

    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.

  3. Determination of 36Cl in nuclear waste from reactor decommissioning.

    Science.gov (United States)

    Hou, Xiaolin; Ostergaard, Lars Frøsig; Nielsen, Sven P

    2007-04-15

    An analytical method for the determination of 36Cl 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 36Cl from the matrix elements, followed by ion-exchange chromatography to remove interfering radionuclides. The purified 36Cl was then measured by liquid scintillation counting. The chemical yield of chlorine, as measured by ICPMS, is above 70% and the decontamination factors for all interfering radionuclides are greater than 10(6). The detection limit of this analytical method for 36Cl is 14 mBq. The method has been used to determine 36Cl in heavy concrete, aluminum, and graphite from the Danish DR-2 research reactor.

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

    Science.gov (United States)

    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.

  5. Distribution and Origin of 36Cl In Allende CAIs

    Energy Technology Data Exchange (ETDEWEB)

    Matzel, J P; Jacobsen, B; Hutcheon, I D; Krot, A N; Nagashima, K; Yin, Q; Ramon, E C; Weber, P; Wasserburg, G J

    2009-12-11

    The abundance of short-lived radionuclides (SLRs) in early solar system materials provide key information about their nucleosynthetic origin and can constrain the timing of early solar system events. Excesses of {sup 36}S ({sup 36}S*) correlated with {sup 35}Cl/{sup 34}S ratios provide direct evidence for in situ decay of {sup 36}Cl ({tau}{sub 1/2} {approx} 0.3 Ma) and have been reported in sodalite (Na{sub 8}Al{sub 6}Si{sub 6}O{sub 24}Cl{sub 2}) and wadalite (Ca{sub 6}Al{sub 5}Si{sub 2}O{sub 16}Cl{sub 3}) in CAIs and chondrules from the Allende and Ningqiang CV carbonaceous chondrites. While previous studies demonstrate unequivocally that {sup 36}Cl was extant in the early solar system, no consensus on the origin or initial abundance of {sup 36}Cl has emerged. Understanding the origin of {sup 36}Cl, as well as the reported variation in the initial {sup 36}Cl/{sup 35}Cl ratio, requires addressing when, where and how chlorine was incorporated into CAIs and chondrules. These factors are key to distinguishing between stellar nucleosynthesis or energetic particle irradiation for the origin of {sup 36}Cl. Wadalite is a chlorine-rich secondary mineral with structural and chemical affinities to grossular. The high chlorine ({approx}12 wt%) and very low sulfur content (<<0.01 wt%) make wadalite ideal for studies of the {sup 36}Cl-{sup 36}S system. Wadalite is present in Allende CAIs exclusively in the interior regions either in veins crosscutting melilite or in zones between melilite and anorthite associated with intergrowths of grossular, monticellite, and wollastonite. Wadalite and sodalite most likely resulted from open-system alteration of primary minerals with a chlorine-rich fluid phase. We recently reported large {sup 36}S* correlated with {sup 35}Cl/{sup 34}S in wadalite in Allende Type B CAI AJEF, yielding a ({sup 36}Cl/{sup 35}Cl){sub 0} ratio of (1.7 {+-} 0.3) x 10{sup -5}. This value is the highest reported {sup 36}Cl/{sup 35}Cl ratio and is {approx}5 times

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

    Science.gov (United States)

    Ivy-Ochs, S.; Kober, F.; Alfimov, V.; Kubik, P. W.; Synal, H.-A.

    2007-06-01

    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 (<0.70 m/Ma) over the last several million years. In contrast, 36Cl data from sanidine in CN23 seem to indicate shorter minimum exposures and more rapid maximum erosion rates.

  7. Nucleogenic {sup 36}Cl, {sup 236}U and {sup 239}Pu in uranium ores

    Energy Technology Data Exchange (ETDEWEB)

    Wilcken, K.M. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia); Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, Rankine Avenue, East Kilbride G75 0QF (United Kingdom)], E-mail: K.Wilcken@suerc.gla.ac.uk; Fifield, L.K.; Barrows, T.T.; Tims, S.G.; Gladkis, L.G. [Department of Nuclear Physics, RSPhysSE, Australian National University, Canberra, ACT 0200 (Australia)

    2008-08-15

    The nucleogenic isotopes {sup 36}Cl, {sup 236}U and {sup 239}Pu are produced naturally in subsurface environments via neutron capture of thermal and epithermal neutrons. Concentrations are, however, very low and accelerator mass spectrometry (AMS) is required for quantitative measurements. A particular challenge is presented by the measurement of {sup 236}U/{sup 238}U ratios down to the level of 10{sup -13} that is expected from rocks with low uranium concentration. Here, we present the AMS methodology that has been developed at the ANU for measuring {sup 236}U/{sup 238}U ratios at this level. The more established methodologies for {sup 36}Cl and {sup 239}Pu measurements are also summarised. These capabilities are then used to characterize the {sup 36}Cl, {sup 236}U and {sup 239}Pu concentrations in a range of uranium ores. A simple model of the neutron production and capture processes in subsurface environments has been developed and is presented. It is shown that nucleogenic {sup 36}Cl, {sup 236}U and {sup 239}Pu can be used to determine both thermal and epithermal neutron fluxes in subsurface environments. Potential applications include uranium exploration and monitoring of the environmental impact of uranium mining.

  8. Nucleogenic 36Cl, 236U and 239Pu in uranium ores

    Science.gov (United States)

    Wilcken, K. M.; Fifield, L. K.; Barrows, T. T.; Tims, S. G.; Gladkis, L. G.

    2008-08-01

    The nucleogenic isotopes 36Cl, 236U and 239Pu are produced naturally in subsurface environments via neutron capture of thermal and epithermal neutrons. Concentrations are, however, very low and accelerator mass spectrometry (AMS) is required for quantitative measurements. A particular challenge is presented by the measurement of 236U/ 238U ratios down to the level of 10 -13 that is expected from rocks with low uranium concentration. Here, we present the AMS methodology that has been developed at the ANU for measuring 236U/ 238U ratios at this level. The more established methodologies for 36Cl and 239Pu measurements are also summarised. These capabilities are then used to characterize the 36Cl, 236U and 239Pu concentrations in a range of uranium ores. A simple model of the neutron production and capture processes in subsurface environments has been developed and is presented. It is shown that nucleogenic 36Cl, 236U and 239Pu can be used to determine both thermal and epithermal neutron fluxes in subsurface environments. Potential applications include uranium exploration and monitoring of the environmental impact of uranium mining.

  9. Search for36Cl in Stripa site groundwaters

    Science.gov (United States)

    Bentley, H.; Brissaud, I.; Elmore, D.; Gove, H.; Ma, X. Z.

    1983-09-01

    Four groundwater samples from the Stripa site have been analysed by accelerator mass spectrometry at the University of Rochester. The36Cl concentrations were found to range from 2.108 to 6.108 atoms per litre of water, whereas the modern concentration is two orders of magnitude lower. A subsurface origin seems to be the explanation of these results.

  10. Some possible evolutionary scenarios suggested by {sup 36}Cl measurements in Guarani aquifer groundwaters

    Energy Technology Data Exchange (ETDEWEB)

    Cresswell, R.G. [CSIRO Land and Water, 120 Meiers Road, Indooroopilly, Queensland 4068 (Australia)], E-mail: richard.cresswell@csiro.au; Bonotto, D.M. [Departamento de Petrologia e Metalogenia, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900 Rio Claro, Sao Paulo (Brazil)], E-mail: danielbonotto@yahoo.com.br

    2008-08-15

    The Guarani aquifer underlies 1.2 M km{sup 2} in the Parana sedimentary basin of South America and is an important source of water for industry, agriculture, and domestic supplies. To determine the sustainability of this aquifer we need to understand the dynamics of the groundwater system. This paper describes the first {sup 36}Cl measurements on aquifer groundwaters and some measurements on South American rainwaters, thought to be indicative of the recharge water. The results are compared to previous work in the region, including other radioisotope analyses. A simple model is developed, incorporating radioactive decay, allowing scenarios to be developed for mixing different waters at different mixing rates. Thus, mixing scenarios consistent with other hydrogeological and hydrogeochemical data could be assessed. A model that mixes fresh recharging waters with formational waters, that contain elevated chloride levels, but low (in situ) {sup 36}Cl levels, can explain most of the results presented here. The expectation that rainwater samples would provide a good end-member for modelling recharge proved problematic, however. As a consequence, it is suggested that either: the recharge waters are not sourced from the same locations as the rains; that the current rainfall and fallout conditions were significantly different in the past; or that the low levels of chloride in rainfall may have allowed some contamination of the samples by old ({sup 36}Cl-free) chloride during the recharge process.

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

    Science.gov (United States)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. AMS Measurement of 36Cl with a Q3D Magnetic Spectrometer at CIAE

    Institute of Scientific and Technical Information of China (English)

    李朝历; 何明; 张伟; 武绍勇; 李振宇; 何贤文; 刘建成; 董克君; 姜山

    2012-01-01

    The ratio of 36Cl/Cl can determine the exposure age of surface rocks and monitor the secular equilibrium of 36Cl of sedimentary and igneous rock in groundwater. Due to the uncertainty effects of different chemical separation processes for removing 36S, there is a high degree of uncertainty in 36Cl accelerator mass spectrometry (AMS) measurements if the ratio of 36Cl/Cl is lower than 10-14. A 36Cl1 AMS higher sensitivity measurement has been set up by using a AE-Q3D method at the China Institute of Atomic Energy (CIAE). The performances of AE-Q3D method for 36Cl-AMS measurement had been systemically studied. The experimental results show that the AE-Q3D method has a higher isobar suppression factor. Taking advantage of direct removing 36S, the sample preparation can be simplified and the uncertainty effects of different chemical separation processes can be reduced in 36Cl AMS measurements.

  14. Ultra-trace analysis of 36Cl by accelerator mass spectrometry: an interlaboratory study.

    Science.gov (United States)

    Merchel, S; Bremser, W; Alfimov, V; Arnold, M; Aumaître, G; Benedetti, L; Bourlès, D L; Caffee, M; Fifield, L K; Finkel, R C; Freeman, S P H T; Martschini, M; Matsushi, Y; Rood, D H; Sasa, K; Steier, P; Takahashi, T; Tamari, M; Tims, S G; Tosaki, Y; Wilcken, K M; Xu, S

    2011-07-01

    A first international (36)Cl interlaboratory comparison has been initiated. Evaluation of the final results of the eight participating accelerator mass spectrometry (AMS) laboratories on three synthetic AgCl samples with (36)Cl/Cl ratios at the 10(-11), 10(-12), and 10(-13) level shows no difference in the sense of simple statistical significance. However, more detailed statistical analyses demonstrate certain interlaboratory bias and underestimation of uncertainties by some laboratories. Following subsequent remeasurement and reanalysis of the data from some AMS facilities, the round-robin data indicate that (36)Cl/Cl data from two individual AMS laboratories can differ by up to 17%. Thus, the demand for further work on harmonising the (36)Cl-system on a worldwide scale and enlarging the improvement of measurements is obvious.

  15. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Late Pleistocene ages for the most recent volcanism and glacial-pluvial deposits at Big Pine volcanic field, California, USA, from cosmogenic 36Cl dating

    Science.gov (United States)

    Vazquez, Jorge A.; Woolford, Jeff M

    2015-01-01

    The Big Pine volcanic field is one of several Quaternary volcanic fields that poses a potential volcanic hazard along the tectonically active Owens Valley of east-central California, and whose lavas are interbedded with deposits from Pleistocene glaciations in the Sierra Nevada Range. Previous geochronology indicates an ∼1.2 Ma history of volcanism, but the eruption ages and distribution of volcanic products associated with the most-recent eruptions have been poorly resolved. To delimit the timing and products of the youngest volcanism, we combine field mapping and cosmogenic 36Cl dating of basaltic lava flows in the area where lavas with youthful morphology and well-preserved flow structures are concentrated. Field mapping and petrology reveal approximately 15 vents and 6 principal flow units with variable geochemical composition and mineralogy. Cosmogenic 36Cl exposure ages for lava flow units from the top, middle, and bottom of the volcanic stratigraphy indicate eruptions at ∼17, 27, and 40 ka, revealing several different and previously unrecognized episodes of late Pleistocene volcanism. Olivine to plagioclase-pyroxene phyric basalt erupted from several vents during the most recent episode of volcanism at ∼17 ka, and produced a lava flow field covering ∼35 km2. The late Pleistocene 36Cl exposure ages indicate that moraine and pluvial shoreline deposits that overlie or modify the youngest Big Pine lavas reflect Tioga stage glaciation in the Sierra Nevada and the shore of paleo-Owens Lake during the last glacial cycle.

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

    Science.gov (United States)

    Heisinger, B.; Nolte, E.

    2000-10-01

    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 K 2O, CaCO 3, granite and concrete and of 53Mn in Fe 2O 3 are given as function of erosion rate. Consequences to determinations of neutron fluences in Hiroshima are discussed.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Distribution, Identification, and Quantification of Residues after Treatment of Ready-To-Eat Salami with (36)Cl-Labeled or Nonlabeled Chlorine Dioxide Gas.

    Science.gov (United States)

    Smith, David J; Giddings, J Michael; Herges, Grant R; Ernst, William

    2016-11-09

    When ready-to-eat salami was treated in a closed system with (36)Cl-labeled ClO2 (5.5 mg/100 g of salami), essentially all radioactivity was deposited onto the salami. Administered (36)ClO2 was converted to (36)Cl-chloride ion (>97%), trace levels of chlorate (<2%), and detectable levels of chlorite. In residue studies conducted with nonlabeled ClO2, sodium perchlorate residues (LOQ, 4 ng/g) were not formed when reactions were protected from light. Sodium chlorate residues were present in control (39.2 ± 4.8 ng/g) and chlorine dioxide treated (128 ± 31.2 ng/g) salami. If sanitation occurred under conditions of illumination, detectable levels (3.7 ± 1.5 ng/g) of perchlorate were formed along with greater quantities of sodium chlorate (183.6 ± 75.4 ng/g). Collectively, these data suggest that ClO2 is chemically reduced by salami and that slow-release formulations might be appropriate for applications involving the sanitation of ready-to-eat meat products.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  3. Implications of 36Cl exposure ages from Skye, northwest Scotland for the timing of ice stream deglaciation and deglacial ice dynamics

    Science.gov (United States)

    Small, David; Rinterknecht, Vincent; Austin, William E. N.; Bates, Richard; Benn, Douglas I.; Scourse, James D.; Bourlès, Didier L.; Hibbert, Fiona D.

    2016-10-01

    Geochronological constraints on the deglaciation of former marine based ice streams provide information on the rates and modes by which marine based ice sheets have responded to external forcing factors such as climate change. This paper presents new 36Cl cosmic ray exposure dating from boulders located on two moraines (Glen Brittle and Loch Scavaig) in southern Skye, northwest Scotland. Ages from the Glen Brittle moraines constrain deglaciation of a major marine terminating ice stream, the Barra-Donegal Ice Stream that drained the former British-Irish Ice Sheet, depending on choice of production method and scaling model this occurred 19.9 ± 1.5-17.6 ± 1.3 ka ago. We compare this timing of deglaciation to existing geochronological data and changes in a variety of potential forcing factors constrained through proxy records and numerical models to determine what deglaciation age is most consistent with existing evidence. Another small section of moraine, the Scavaig moraine, is traced offshore through multibeam swath-bathymetry and interpreted as delimiting a later stillstand/readvance stage following ice stream deglaciation. Additional cosmic ray exposure dating from the onshore portion of this moraine indicate that it was deposited 16.3 ± 1.3-15.2 ± 0.9 ka ago. When calculated using the most up-to-date scaling scheme this time of deposition is, within uncertainty, the same as the timing of a widely identified readvance, the Wester Ross Readvance, observed elsewhere in northwest Scotland. This extends the area over which this readvance has potentially occurred, reinforcing the view that it was climatically forced.

  4. Generation of nanopores during desorption of NH3 from Mg(NH3)6Cl2

    DEFF Research Database (Denmark)

    Hummelshøj, Jens Strabo; Sørensen, Rasmus Zink; Kostova, M.Y.;

    2006-01-01

    It is shown that nanopores are formed during desorption of NH3 from Mg(NH3)6Cl2, which has been proposed as a hydrogen storage material. The system of nanopores facilitates the transport of desorbed ammonia away from the interior of large volumes of compacted storage material. DFT calculations show...... that there exists a continuous path from the initial Mg(NH3)6Cl2 material to MgCl2 that does not involve large-scale material transport. Accordingly, ammonia desorption from this system is facile....

  5. Precision Measurement of the 29Si, 33S, and 36Cl Binding Energies

    CERN Document Server

    Dewey, M S; Deslattes, R D; Doll, C; Jentschel, M; Mutti, P

    2006-01-01

    The binding energies of 29Si, 33S, and 36Cl have been measured with a relative uncertainty $< 0.59 \\times 10^{-6}$ using a flat-crystal spectrometer. The unique features of these measurements are 1) nearly perfect crystals whose lattice spacing is known in meters, 2) a highly precise angle scale that is derived from first principles, and 3) a gamma-ray measurement facility that is coupled to a high flux reactor with near-core source capability. The binding energy is obtained by measuring all gamma-rays in a cascade scheme connecting the capture and ground states. The measurements require the extension of precision flat-crystal diffraction techniques to the 5 to 6 MeV energy region, a significant precision measurement challenge. The binding energies determined from these gamma-ray measurements are consistent with recent highly accurate atomic mass measurements within a relative uncertainty of $4.3 \\times 10^{-7}$. The gamma-ray measurement uncertainties are the dominant contributors to the uncertainty of th...

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

    Directory of Open Access Journals (Sweden)

    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.

    Science.gov (United States)

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

    Science.gov (United States)

    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.

  9. Interlaboratory study of the ion source memory effect in {sup 36}Cl accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pavetich, Stefan, E-mail: s.pavetich@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01314 Dresden (Germany); Akhmadaliev, Shavkat [Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01314 Dresden (Germany); Arnold, Maurice; Aumaître, Georges; Bourlès, Didier [Aix-Marseille Université, CEREGE CNRS-IRD, F-13545 Aix-en-Provence (France); Buchriegler, Josef [Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01314 Dresden (Germany); University of Vienna, Faculty of Physics, VERA Laboratory, Währingerstraße 17, 1090 Vienna (Austria); Golser, Robin [University of Vienna, Faculty of Physics, VERA Laboratory, Währingerstraße 17, 1090 Vienna (Austria); Keddadouche, Karim [Aix-Marseille Université, CEREGE CNRS-IRD, F-13545 Aix-en-Provence (France); Martschini, Martin [University of Vienna, Faculty of Physics, VERA Laboratory, Währingerstraße 17, 1090 Vienna (Austria); Merchel, Silke; Rugel, Georg [Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01314 Dresden (Germany); Steier, Peter [University of Vienna, Faculty of Physics, VERA Laboratory, Währingerstraße 17, 1090 Vienna (Austria)

    2014-06-01

    Highlights: • Long-term memory effect in negative ion sources investigated for chlorine isotopes. • Interlaboratory comparison of four up-to date negative ion sources. • Ion source improvement at DREAMS for minimization of long-term memory effect. • Long-term memory effect is the limitation for precise AMS data of volatile elements. • Findings to be considered for samples with highly variable ratios of {sup 36}Cl/Cl and {sup 129}I/I. - Abstract: Understanding and minimization of contaminations in the ion source due to cross-contamination and long-term memory effect is one of the key issues for accurate accelerator mass spectrometry (AMS) measurements of volatile elements. The focus of this work is on the investigation of the long-term memory effect for the volatile element chlorine, and the minimization of this effect in the ion source of the Dresden accelerator mass spectrometry facility (DREAMS). For this purpose, one of the two original HVE ion sources at the DREAMS facility was modified, allowing the use of larger sample holders having 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, an interlaboratory comparison had been initiated. The long-term memory effect of the four Cs sputter ion sources at DREAMS (two sources: original and modified), ASTER (Accélérateur pour les Sciences de la Terre, Environnement, Risques) and VERA (Vienna Environmental Research Accelerator) had been investigated by measuring samples of natural {sup 35}Cl/{sup 37}Cl-ratio and samples highly-enriched in {sup 35}Cl ({sup 35}Cl/{sup 37}Cl ∼ 999). Besides investigating and comparing the individual levels of long-term memory, recovery time constants could be calculated. The tests show that all four sources suffer from long-term memory, but the modified DREAMS ion source showed the lowest level of contamination. The recovery times of the four ion

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. NPP ATMS Snowfall Rate Product

    Science.gov (United States)

    Meng, Huan; Ferraro, Ralph; Kongoli, Cezar; Wang, Nai-Yu; Dong, Jun; Zavodsky, Bradley; Yan, Banghua

    2015-01-01

    Passive microwave measurements at certain high frequencies are sensitive to the scattering effect of snow particles and can be utilized to retrieve snowfall properties. Some of the microwave sensors with snowfall sensitive channels are Advanced Microwave Sounding Unit (AMSU), Microwave Humidity Sounder (MHS) and Advance Technology Microwave Sounder (ATMS). ATMS is the follow-on sensor to AMSU and MHS. Currently, an AMSU and MHS based land snowfall rate (SFR) product is running operationally at NOAA/NESDIS. Based on the AMSU/MHS SFR, an ATMS SFR algorithm has been developed recently. The algorithm performs retrieval in three steps: snowfall detection, retrieval of cloud properties, and estimation of snow particle terminal velocity and snowfall rate. The snowfall detection component utilizes principal component analysis and a logistic regression model. The model employs a combination of temperature and water vapor sounding channels to detect the scattering signal from falling snow and derive the probability of snowfall (Kongoli et al., 2015). In addition, a set of NWP model based filters is also employed to improve the accuracy of snowfall detection. Cloud properties are retrieved using an inversion method with an iteration algorithm and a two-stream radiative transfer model (Yan et al., 2008). A method developed by Heymsfield and Westbrook (2010) is adopted to calculate snow particle terminal velocity. Finally, snowfall rate is computed by numerically solving a complex integral. NCEP CMORPH analysis has shown that integration of ATMS SFR has improved the performance of CMORPH-Snow. The ATMS SFR product is also being assessed at several NWS Weather Forecast Offices for its usefulness in weather forecast.

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

    Science.gov (United States)

    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. Reconstructing the paleoseismic history of the Priene-Sazli Fault using 36Cl cosmogenic nuclide dating method, Western Anatolia, Turkey

    Science.gov (United States)

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

    2014-05-01

    The 300-km wide West Anatolian Extensional Province is one of the regions of intense seismic activity in the world within the Alpine-Himalayan belt. Deformation pattern in the area is controlled by three major E-W trending graben systems of Gediz, Küçük Menderes and Büyük Menderes which have been formed as a result of roughly N-S extensional tectonic regime since the early Miocene. These graben systems show evidences of surface faulting during the Pleistocene-Holocene and are geomorphologically characterized by well-exposed limestone normal fault scarps with a relief of tens of meters and well-preserved slickenlines. Since limestones are resistant to weathering, the limestone scarps can efficiently record several past earthquakes. Cosmogenic 36Cl is the only element to identify and date the rupture events. Each rupture causes exposure of previously buried section of the scarp to the surface. Accordingly, due to being well enough exposed to cosmic rays, accumulation of 36Cl accelerates during period of quiescence. Thus, distribution of measured 36Cl concentrations can be applied to investigate periods of seismic activity and inactivity and also to calculate the vertical displacement along the fault plane in association with each rupture. In this study, we focus on the Priene-Sazli Fault, located on the most western part of Büyük Menderes graben. Along the active fault zone, well exposed archaeological sites (e.g. Priene) have been discovered, where destructive historical earthquakes have left evidence of ancient damages in the historical period and during the 20th century. The Priene-Sazli Fault caused the July 16, 1955 Söke-Balat earthquake (M=6.8) with fault-plane solution indicating of normal southeast downthrow along with subsidiary dextral motion. We collected 117 samples from four continuous strips on the Priene-Sazli Fault to measure 36Cl concentrations. We used a new Matlab code to identify the significant ruptures and their timing. Our preliminary

  14. Seismic slip history of the Pizzalto fault (Central Apennines, Italy) using in situ 36Cl cosmogenic dating

    Science.gov (United States)

    Delli Rocioli, Mattia; Pace, Bruno; Benedetti, Lucilla; Visini, Francesco; Guillou, Valery; Bourlès, Didier; Arnorld, Maurice; Aumaître, Georges; Keddadouche, Karim

    2013-04-01

    A prerequisite to constrain fault-based and time-dependent earthquake rupture forecast models is to acquire data on the past large earthquake frequency on an individual seismogenic source. Here we present a paleoseismological study on the Pizzalto fault using the in situ produced cosmogenic nuclide 36Cl (Schlagenhauf et al., 2011). The Pizzalto fault, located in central Italy about 50 km southeast of the epicenter of L'Aquila 2009 earthquake, is about 12 km long, SW dipping and belongs to the 30 km long Rotella-Aremogna active normal fault system. Recent activity along the Pizzalto fault is suggested by the presence of a continuous and linear 2 to 5 m high limestone fault scarp that was sampled every 10 cm at a site located in its particularly well-preserved central portion. 49 samples have been chemically processed and measured, and their 36Cl and Cl concentrations have been determined using isotope dilution mass spectrometry at the French AMS national facility ASTER located at CEREGE. Modeling the in situ 36Cl concentration with the scarp height allow deciphering the age and slip of the last major earthquake events on the fault. To derive those earthquake parameters, we used the published Matlab code from Schlagenhauf et al. (2011) that we implemented with a Monte Carlo approach to explore a large number of earthquake recurrence scenarios varying both the number of events, their slip and their ages. The "a priori" constraints input in the Monte Carlo code were: 1-the number of events, which is given by the stacking of individual probability density functions (assumed to be Gaussian) of each sample concentration; and, 2-the cumulative slip that should be equal to the height of the fault scarp. The first results show that 36Cl concentrations are reproduced better considering five events occurring over the last 5 ka and a previous one at about 13 ka. This suggests that most earthquake events clustered during a period of intense seismic activity preceded by a longer

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

    DEFF Research Database (Denmark)

    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...

  16. Production Rates of Cosmogenic Nuclides Deep in the Moon

    Science.gov (United States)

    Reedy, R. C.; Masarik, J.

    1995-09-01

    Measurements of radionuclide activities in Apollo samples extend to depths of only about 400 g/cm2 in the Moon. Some Apollo samples and lunar meteorites probably have significant concentrations of cosmogenic nuclides made while they were buried at depths greater than 400 g/cm2. We report here initial calculations for production rates of cosmogenic nuclides for depths in the Moon down to 1500 g/cm2. The LAHET Code System (LCS) [1] was used to numerically simulate the irradiation of the Moon by galactic-cosmic-ray particles and to calculate particle fluxes and production rates of various cosmogenic nuclides. The advantage of these calculations is that the LCS physical model used for the production and transport of particles in the Moon has no free parameters. Some previous models, such as Reedy and Arnold (1972) [2], had semi-empirical or adopted parameters that never were tested below about 400 g/cm2. Our simulations started by selecting the energy and direction of the primary particle that starts a particle cascade and following all particles until they are removed by nuclear interactions or escape from the Moon. The calculations were validated by modeling production of 10Be, 26Al, 36Cl, and 53Mn in the Apollo 15 drill core and getting good agreement with measurements to depths of about 400 g/cm2 [3]. We used the composition of the Apollo 15 deep drill core for these calculations, assumed a density of 1.5 g/cm3, and did calculations to a depth of 1000 cm (1500 g/cm2). We ran 5 million incident particles to try to get good statistics at great depths. Statistical uncertainties for depths below about 1000 g/cm2 were about 10%, so we splined the results for depths below 750 g/cm2. We reproduced our original results [3] down to 500 g/cm2, extended the calculated production rates of those four radionuclides to 1500 g/cm2, and also calculated production rates of 14C, 21Ne, 22Ne, and 38Ar from 0 to 1500 g/cm2. As reported earlier [3], production rates for various

  17. Decadal {sup 10}Be, {sup 26}Al and {sup 36}Cl QA measurements on the SUERC 5 MV accelerator mass spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Sheng, E-mail: s.xu@suerc.gla.ac.uk; Freeman, Stewart P.H.T.; Rood, Dylan H.; Shanks, Richard P.

    2015-10-15

    We quantify the routine performance and uncertainties of cosmogenic {sup 10}Be, {sup 26}Al and {sup 36}Cl QA measurements made on the SUERC 5 MV accelerator mass spectrometer since 2004. Our analysis compiles data from primary (NIST SRM4325 for {sup 10}Be, Purdue Z92-0222 for {sup 26}Al and Purdue Z93-0005 for {sup 36}Cl) and secondary (Nishiizumi’s series for {sup 10}Be, {sup 26}Al and {sup 36}Cl) reference samples with {sup 10}Be/{sup 9}Be, {sup 26}Al/{sup 27}Al and {sup 36}Cl/Cl ratios ranging between 10{sup −11} and 10{sup −13}. Our decadal datasets indicate that the {sup 10}Be, {sup 26}Al and {sup 36}Cl secondary standard samples have average standard deviations 1.1%–2.4%, 1.1%–2.8% and 3.0%–3.1%, respectively. The average statistical uncertainties based on counting statistics are 1.0%–1.8%, 0.9%–2.8% and 2.5%–2.7% for {sup 10}Be, {sup 26}Al and {sup 36}Cl, respectively. These indicate additional uncertainties (0.6%–1.6% for {sup 10}Be, 0.5%–2.4% for {sup 26}Al and 1.4%–1.7% for {sup 36}Cl) above those calculated from counting statistics alone. The average differences between the measured and the nominal values are within ±1% in 13 of 14 secondary samples.

  18. Glacial and volcanic evolution on Nevado Coropuna (Tropical Andes) based on cosmogenic 36Cl surface exposure dating

    Science.gov (United States)

    Úbeda, J.; Palacios, D.; Vázquez-Selém, L.

    2012-04-01

    We have reconstructed the evolution of the paleo-glaciers of the volcanic complex Nevado Coropuna (15°S, 72°W; 6377 m asl) through the interpretation and dating of geomorphological evidences. Surface exposure dating (SED) based on the accumulation of 36Cl on the surface of moraine boulders, polished bedrock and lava flows allowed: 1) to confirm that the presence of ice masses in the region dates back to >80ka; 2) to produce chronologies of glacial and volcanic phases for the last ~21 ka; and 3) to obtain evidences of the reactivation of volcanic activity after the Last Glacial Maximum. Bromley et al. (2009) presented 3He SED ages of 21 ka for moraine boulders on the Mapa Mayo valley, to the North of Nevado Coropuna. Our 36Cl SED SED for moraine boulders from the valleys on the NE sector of the volcanic complex suggest a maximum initial advance between 20 and 16 ka, followed by another expansion of similar extent at 12-11 ka. On the Southern slope of Nevado Coropuna, the 36Cl ages show a maximum initial advance that reaches to the level of the Altiplano at 14 ka, and a re-advance at ~10-9 ka BP. Other data show minor re-advances at 9 ka on the Northern slope and at 6 ka to the South of the volcanic complex. These minor positive pulses interrupted a fast deglaciation process during the Holocene as shown by two series of 36Cl SED from polished rock surfaces on successively higher altitudes along the valleys of rivers Blanco and Cospanja, to the SW and SE. Despite the global warming occuring since 20 ka, deduced from the record of sea surface paleo-temperature of the Galapago Islands (Lea et al, 2006), the evolution of the fresh-water plankton from Lake Titicaca (Fritz et al, 2007) is consistent with sustained glacial conditions until 10-9 ka as suggested by the present work. Exposure ages of three lava flows indicate a reactivation of the magmatic system as the paleo-glaciers abandonned the slopes. The eruptive activity migrated from the West, where we found a lava

  19. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. NESDIS Blended Rain Rate (RR) Products

    Data.gov (United States)

    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. How is entropy production rate related to chemical reaction rate?

    CERN Document Server

    Banerjee, Kinshuk

    2013-01-01

    The entropy production rate is a key quantity in irreversible thermodynamics. In this work, we concentrate on the realization of entropy production rate in chemical reaction systems in terms of the experimentally measurable reaction rate. Both triangular and linear networks have been studied. They attain either thermodynamic equilibrium or a non-equilibrium steady state, under suitable external constraints. We have shown that the entropy production rate is proportional to the square of the reaction velocity only around equilibrium and not any arbitrary non-equilibrium steady state. This feature can act as a guide in revealing the nature of a steady state, very much like the minimum entropy production principle. A discussion on this point has also been presented.

  2. Production of cosmogenic radionuclides at great depth: A multi element approach

    Science.gov (United States)

    Braucher, R.; Merchel, S.; Borgomano, J.; Bourlès, D. L.

    2011-09-01

    For the last two decades, in situ produced cosmogenic nuclides are increasingly applied in Earth sciences to quantify surface processes. In parallel, significant reduction of the analytical uncertainties linked to advances in accelerator mass spectrometry (AMS) allows more precise measurements. However, among all the published works on cosmogenic nuclides, only few studies are dedicated to a better understanding of their production systematic or to a better constrain of the physical parameters involved in their production. Thus, an approach to investigate in situ produced cosmogenic nuclides 10Be, 26Al and 36Cl along a single 11-meter long core drilled from the surface and composed of carbonates and quartzose conglomerates has been launched. These measurements have been used to quantify muon-induced productions based on natural samples for each studied nuclide. Contrary to the current most oftenly used calculation of muon-induced production parameters which are based on irradiation experiments at discrete energies, productions based on natural samples are considering the entire energy range of particles reaching the ground surface. The evolution of 36Cl concentrations with depth needs to agree with those parameters deduced from 10Be and 26Al data. This is optimized when considering a fast muon-induced 36Cl production contribution and a spallation production rate at Sea Level High Latitude (SLHL) of (42.0 ± 2.0) atoms 36Cl·g·Ca - 1 ·a - 1 (1 sigma uncertainty).

  3. The French accelerator mass spectrometry facility ASTER after 4 years: Status and recent developments on 36Cl and 129I

    Science.gov (United States)

    Arnold, Maurice; Aumaître, Georges; Bourlès, Didier L.; Keddadouche, Karim; Braucher, Régis; Finkel, Robert C.; Nottoli, Emmanuelle; Benedetti, Lucilla; Merchel, Silke

    2013-01-01

    Since the acceptance tests of the French 5 MV accelerator mass spectrometry facility ASTER in 2007, routine measurement conditions for the long-lived radionuclides 10Be and 26Al have been established. Yearly sample throughput as high as over 3300 unknowns has been reached for 10Be in 2010. Cross-contamination for volatile elements has been largely solved by an ion source upgrade allowing 36Cl measurements at ASTER. However, recent long-term tests using 35Cl/37Cl samples with strongly varying ratios have shown that identical targets lead to different 35Cl/37Cl results at the 2-4% level when being measured after a time gap of 24 h while the source is running other samples. Besides time dependent mass fractionation, another likely reason for this effect might be source memory, thus, asking for sophisticated measurement strategies and improved data evaluation and eventually further ion source improvement. Finally, after establishing quality assurance by cross-calibration of secondary in-house 26Al and 41Ca standards and taking part in round-robin exercises of 10Be and 36Cl, a two-step cross-calibration of secondary in-house 129I standards has been performed. The NIST 3231 standard containing 129I/127I at (0.981 ± 0.012) × 10-6 has been used for step-wise dilution with NaI to produce gram-quantities of lower-level standards for every-day use. The resulting material SM-I-9 (129I/127I: ∼1 × 10-9) has been measured vs. AgI produced using minimum chemistry from the two NIST ampoules containing a solution with a nominal ratio 129I/127I of (0.982 ± 0.012) × 10-8. In a second stage, SM-I-10 and SM-I-11 with ratios of ∼1 × 10-10 and ∼1 × 10-11, respectively, have been cross-calibrated against SM-I-9. Individual uncertainties of the traceable secondary standards are 1.3-1.4% (2σ), mainly originating from the given uncertainty of the primary NIST 3231 at the 10-8 level. The cross-contamination for iodine is in the range of 0.4-0.6% within the first 20 h of running

  4. A finite horizon production model with variable production rates and constant demand rate

    OpenAIRE

    2002-01-01

    In this paper we present a finite horizon single product single machine production problem. Demand rate and all the cost patterns do not change over time. However, end of horizon effects may require production rate adjustments at the beginning of each cycle. It is found that no such adjustments are required. The machine should be operated either at minimum speed (i.e. production rate = demand rate; shortage is not allowed), avoiding the buildup of any inventory, or at maximum s...

  5. Towards a model for protein production rates

    CERN Document Server

    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.

  6. Towards a Model for Protein Production Rates

    Science.gov (United States)

    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.

  7. Inner gorges incision history: A proxy for deglaciation? Insights from Cosmic Ray Exposure dating (10Be and 36Cl) of river-polished surfaces (Tinée River, SW Alps, France)

    Science.gov (United States)

    Rolland, Y.; Petit, C.; Saillard, M.; Braucher, R.; Bourlès, D.; Darnault, R.; Cassol, D.

    2017-01-01

    10Be and 36Cl Cosmic Ray Exposure (CRE) dating performed on river polished surfaces of river gorges in a mountain-to-sea river system in the French SW Alps highlights transient erosional events involving incision rates >10 mm a-1. These events took place during the last two major deglaciation phases following (1) the Last Glacial Maximum (LGM) at 16-14 ka, (2) the Younger Dryas at 8-11 ka, and during the warm and humid Holocene climatic optimum at 4-5 ka. These periods of high incision rates (3- > 30 mma-1) alternated with periods of low incision rates (<1 mm a-1), which probably correspond to a long-term equilibrium between incision and relative uplift. The Alpine river staircase shape profiles evidence local and transient responses that are ascribed to cumulate disequilibrium after the long-time-spanned glaciations. After each glaciation, rivers rush down to get closer to their equilibrium profile. Incision is amplified both by the sediment discharge due to the erosion of moraines and by landslides triggered by the glacier retreat.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Establishing constraints on groundwater ages with {sup 36}Cl, {sup 14}C, {sup 3}H, and noble gases: A case study in the eastern Paris basin, France

    Energy Technology Data Exchange (ETDEWEB)

    Lavastre, Veronique, E-mail: veronique.lavastre@univ-st-etienne.fr [CEREGE, CNRS - UMR 6635, Europole Mediterraneen de l' Arbois, 13545 Aix-en-Provence (France)] [CNAB, CNRS - UMR 5084, BP120, 33175 Gradignan (France)] [Laboratoire de Geochimie des Isotopes Stables, Institut de Physique du Globe de Paris, Universite Paris 7, UMR CNRS 7154, 2, Place Jussieu, 75251 Paris Cedex 05 (France); Salle, Corinne Le Gal La [CEREGE, CNRS - UMR 6635, Europole Mediterraneen de l' Arbois, 13545 Aix-en-Provence (France)] [GIS, Universite de Nimes, 150 Rue Georges Besse, 30035 Nimes (France); Michelot, Jean-Luc [IDES, UMR 8148 CNRS - Universite Paris-Sud, Bat. 504, 91405 Orsay (France); Giannesini, Sophie [CEREGE, CNRS - UMR 6635, Europole Mediterraneen de l' Arbois, 13545 Aix-en-Provence (France)] [GIS, Universite de Nimes, 150 Rue Georges Besse, 30035 Nimes (France); Benedetti, Lucilla [CEREGE, CNRS - UMR 6635, Europole Mediterraneen de l' Arbois, 13545 Aix-en-Provence (France); Lancelot, Joel [CEREGE, CNRS - UMR 6635, Europole Mediterraneen de l' Arbois, 13545 Aix-en-Provence (France)] [GIS, Universite de Nimes, 150 Rue Georges Besse, 30035 Nimes (France); Lavielle, Bernard [CNAB, CNRS - UMR 5084, BP120, 33175 Gradignan (France); Massault, Marc [IDES, UMR 8148 CNRS - Universite Paris-Sud, Bat. 504, 91405 Orsay (France); Thomas, Bertrand; Gilabert, Eric [CNAB, CNRS - UMR 5084, BP120, 33175 Gradignan (France); Bourles, Didier [CEREGE, CNRS - UMR 6635, Europole Mediterraneen de l' Arbois, 13545 Aix-en-Provence (France); Clauer, Norbert [Centre de Geochimie de la Surface (CNRS/ULP), Universite Louis Pasteur, 1 rue Blessig, 67084 Strasbourg (France); Agrinier, Pierre [Laboratoire de Geochimie des Isotopes Stables, Institut de Physique du Globe de Paris, Universite Paris 7, UMR CNRS 7154, 2, Place Jussieu, 75251 Paris Cedex 05 (France)

    2010-01-15

    Groundwaters from the Tithonian/Kimmeridgian, Oxfordian and Upper Dogger aquifers, within the eastern part of the Paris basin (France), were characterised using {sup 3}H, {sup 14}C and {sup 36}Cl, and noble gases tracers, to evaluate their residence times and determine their recharge period. This information is an important prerequisite to evaluating the confinement properties of the Callovo-Oxfordian clay formation sandwiched between the Oxfordian aquifer and the Dogger aquifer, currently being investigated by the French nuclear waste management agency (Andra) for radioactive waste disposal. Data presented in this paper are used to test 4 hypotheses. (1)The Oxfordian limestone is isolated from the overlying Tithonian/Kimmeridgian surface aquifer. This first hypothesis is supported by the presence of measurable {sup 3}H activities in groundwaters from the surface aquifer (6-11 TU), and by its absence in groundwaters derived from deeper aquifers (<3 TU), as well as by geochemical data from earlier studies. (2)The Callovo-Oxfordian clay sequence in the vicinity of the URL serves as an effective barrier to advective flow and transport between the underlying Upper Dogger aquifer and the overlying Oxfordian limestone aquifer. This second hypothesis is supported by relatively low concentrations of Cl (3.5-78 mg L{sup -1}), Na (15-145 mg L{sup -1}), Br (0.08-0.4 mg L{sup -1}) and {sup 4}He{sub rad} (0.2-2.3 ccSTP g{sup -1}) and slightly higher {sup 36}Cl/Cl ratios (2.7-59 x 10{sup -15} at at{sup -1}) in groundwaters from the Oxfordian aquifer, compared to those from the Upper Dogger aquifer (345-4027 mgCl L{sup -1}; 402-2390 mgNa L{sup -1}, 1.8-22.2 mgBr L{sup -1}, 1.6-37.2 ccSTP He g{sup -1}, 1-5 x 10{sup -15} at {sup 36}Cl at{sup -1} Cl). (3)Groundwaters from the Oxfordian aquifer, in the vicinity of URL are pre-Holocene, with residence times exceeding 10 ka. Geochemical and isotopic lines of evidence for this hypothesis include: (a){delta}{sup 13}C values measured on

  10. Exploring the cliff retreat response to base level change using SFM photogrammetry and cosmogenic 36Cl, Coal Cliffs, Utah, USA

    Science.gov (United States)

    Sheehan, C.; Ward, D.

    2015-12-01

    The retreat of cliffbands is an important erosional process within the relatively undeformed sedimentary layers of the Colorado Plateau. Many iconic cliff landforms, including those of Monument Valley and Grand Canyon, are maintained by the interaction of these different rock types. A several kilometer thickness of incised sandstone and shale formations allow this region to act as a natural laboratory for studying the effects of variable lithologies on landscape evolution. Cliffband morphology and retreat on the plateau are controlled by several factors that may vary over time and space, including lithology, rate and distribution of rockfall debris, bedrock structure, baselevel, and climate. The relative importance of each factor in setting rates of cliff retreat are not entirely clear. Because regional headwaters are commonly sourced at cliff bases, these landforms are often the final and slowest areas to respond to baselevel changes, allowing rockfall and other local stochastic processes to overwhelm the erosional response to a baselevel forcing. The roles of these processes are difficult to assess because very few measurements of retreat rates over geomorphic timescales (103-106 years) have been produced, and thus changes in cliffband position through time have only been constrained by inferences made from the regional erosional history. Here, we control for climate and rock type by focusing on a continuous, 40-kilometer section of the lithologically consistent Coal Cliffs in Emery County, Utah. This area presents several natural experiments illustrating cliffband response to different forcings, including relict surfaces reflecting a baselevel change, drainage divides across which the adjustment to base level change may be asynchronous, a zone wherein the caprock layer has been removed by backscarp erosion, and a generally continuous gradient in cliff height from 50 to >200 meters along the cliffline. We employ terrestrial Cl36 exposure dating on terraces, talus

  11. Forecasting New Product Sales from Likelihood of Purchase Ratings

    OpenAIRE

    William J. Infosino

    1986-01-01

    This paper compares consumer likelihood of purchase ratings for a proposed new product to their actual purchase behavior after the product was introduced. The ratings were obtained from a mail survey a few weeks before the product was introduced. The analysis leads to a model for forecasting new product sales. The model is supported by both empirical evidence and a reasonable theoretical foundation. In addition to calibrating the relationship between questionnaire ratings and actual purchases...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Production rates of major regional Floras

    NARCIS (Netherlands)

    Polhill, R.M.

    1989-01-01

    The ambitious programme of major regional Floras for developing countries initiated in the late 1940’s to 1960’s is now mostly under serious reappraisal because of the slow rates of progress, coupled with political changes, financial restrictions and evolving technology. From our present viewpoint i

  14. An ETAS model with varying productivity rates

    Science.gov (United States)

    Harte, D. S.

    2014-07-01

    We present an epidemic type aftershock sequenc (ETAS) model where the offspring rates vary both spatially and temporally. This is achieved by distinguishing between those space-time volumes where the interpoint space and time distances are small, and those where they are considerably larger. We also question the nature of the background component in the ETAS model. Is it simply a temporal boundary correction (t = 0) or does it represent an additional tectonic process not described by the aftershock component? The form of these stochastic models should not be considered to be fixed. As we accumulate larger and better earthquake catalogues, GPS data, strain rates, etc., we have the ability to ask more complex questions about the nature of the process. By fitting modified models consistent with such questions, we should gain a better insight into the earthquake process. Hence, we consider a sequence of incrementally modified ETAS type models rather than `the' ETAS model.

  15. Weak Interaction Neutron Production Rates in Fully Ionized Plasmas

    CERN Document Server

    Widom, A; Srivastava, Y N

    2013-01-01

    Employing the weak interaction reaction wherein a heavy electron is captured by a proton to produce a neutron and a neutrino, the neutron production rate for neutral hydrogen gases and for fully ionized plasmas is computed. Using the Coulomb atomic bound state wave functions of a neutral hydrogen gas, our production rate results are in agreement with recent estimates by Maiani {\\it et al}. Using Coulomb scattering state wave functions for the fully ionized plasma, we find a substantially enhanced neutron production rate. The scattering wave function should replace the bound state wave function for estimates of the enhanced neutron production rate on water plasma drenched cathodes of chemical cells.

  16. Aftershock production rate of driven viscoelastic interfaces.

    Science.gov (United States)

    Jagla, E A

    2014-10-01

    We study analytically and by numerical simulations the statistics of the aftershocks generated after large avalanches in models of interface depinning that include viscoelastic relaxation effects. We find in all the analyzed cases that the decay law of aftershocks with time can be understood by considering the typical roughness of the interface and its evolution due to relaxation. In models where there is a single viscoelastic relaxation time there is an exponential decay of the number of aftershocks with time. In models in which viscoelastic relaxation is wave-vector dependent we typically find a power-law dependence of the decay rate that is compatible with the Omori law. The factors that determine the value of the decay exponent are analyzed.

  17. Hydrological implications of deep production of chlorine-36

    Science.gov (United States)

    Fontes, J. Ch.; Brissaud, I.; Michelot, J. L.

    1984-11-01

    Among the possible origins of 36Cl in ground waters: (1) cosmic radiation in the atmosphere, (2) cosmic in the subsurface, (3) deep underground, (4) marine nuclear tests, the deep component is generally taken as negligible. This could be the case in rocks with low or medium uranium and thorium contents and low content in elements with high cross sections for neutron production. However, under favourable geological conditions (crystalline or metamorphic rocks, sedimentary rocks of detrital and endoreic origin), the deep neutron flux may be significant and thus give rise to an underground production of 36Cl by reaction on 35Cl atoms from ground water and possibly from fluid inclusions. This production is easily recognizable when the 36Cl content per liter of old (tritium free) water is greater than the "modern" 36Cl content of precipitation corrected for evapotranspiration. A clear example is the deep ground water system of the Stripa granite, in Sweden, where values as high as 7 × 10 8 atoms of 36Cl per liter are observed. In this particular example, the initial content of the recharge may be neglected and a residence time of the chloride ions may be estimated if the neutron flux is known. Such favourable situations may be encountered when saline intrusions reach the ground water system in uranium and thorium rich rocks. An ambiguity may arise if the deep 36Cl production corresponds to values of apparent decay of meteoric 36Cl. This is illustrated by 36Cl content of deep ground waters from the Sahara (aquifer of the Continental Intercalaire). Values of 6 and 20 × 10 8 atoms per liter may be interpreted in terms either of very high concentration of rain water by evatranspiration during recharge processes, or of deep 36Cl production. A discussion based on additional paleohydrological information (stable isotopes, noble gas contents) suggests an intraformational generation of 36Cl. However, in such a case, the differences in activity ratio 36Cl/Cl tot and in absolute

  18. Radiolytic hydrogen production from process vessels in HB line - production rates compared to evolution rates and discussion of LASL reviews

    Energy Technology Data Exchange (ETDEWEB)

    Bibler, N.E.

    1992-11-12

    Hydrogen production from radiolysis of aqueous solutions can create a safety hazard since hydrogen is flammable. At times this production can be significant, especially in HB line where nitric acid solutions containing high concentrations of Pu-238, an intense alpha emitter, are processed. The hydrogen production rates from these solutions are necessary for safety analyses of these process systems. The methods and conclusions of hydrogen production rate tests are provided in this report.

  19. Seismic slip history of the Aterno-Sulmona fault system in central Apennines (Italy) using in situ produced 36Cl cosmic ray exposure dating.

    Science.gov (United States)

    Jim, T.; Benedetti, L. C.; Bruno, P.; Visini, F.; Aumaitre, G.; Bourles, D. L.

    2014-12-01

    Acquiring long records of past earthquakes on a large population of faults is a key step to understand how strain release along those fault systems varies spatially and temporally.In central Italy, NE-SW extension (~4 mm/yr) is accommodated on a wide normal fault system (50 x 100km). Benedetti et al. (2013) found that 7 of these faults, belonging to the Fucino fault system, have their seismic activity synchronized during short (less than 1 ka) paroxysmal phases of activity. 36Cl measurements and rare earth elements (REE) concentrations were used to reconstruct the seismic slip history of four major faults belonging to an adjacent 30-km-long fault system, the Aterno-Sulmona fault system, at the southeastward tip of the Paganica fault that ruptured during the 2009 L'Aquila earthquake.The preliminary results suggest that 3-7 seismic events have occurred on each fault over the last 11 ka (from NE to SW the Roccapreturo, the Castel di Ieri, the Roccacasale and the Pizzalto faults), with 50 cm to 2 m of associated slip per event. These events appear clustered within intense period of seismic activity lasting less than 1ka (2 to 4 seismic events) separated by 2 to 3 ka periods with no seismic events. The most recent recorded paroxysmal activity occurred about 2.5 ka ago with all four studied faults rupturing in more than 15 earthquakes over a period lasting less than 1ka. These results thus suggest that, as already observed on the Fucino fault system, the seismic activity of the Aterno-Sulmona fault system is also synchronized during short periods of paroxysmal seismic activity.When clustering periods are compared, the seismic activity of the Fucino and the Aterno-Sulmona fault system, are, however, apparently unsynchronized since the most recent clustering period for the Aterno-Sulmona system corresponds to a quiescent period for the Fucino fault system.

  20. The economic production lot size model extended to include more than one production rate

    DEFF Research Database (Denmark)

    Larsen, Christian

    2001-01-01

    btween the demand rate and the production rate which minimizes unit production costs, and should be used in an increasing order. Then, given the production rates, we derive closed-form expressions for all optimal runtimes as well as the minimum average cost. This analysis reveals that it is the size......We study an extension of the economic production lot size model, where more than one production rate can be used during a cycle. Moreover, the production rates, as well as their corresponding runtimes are decision variables. First, we show that all production rates should be choosen in the interval...... of the setup cost that determines the need for being able to use several production rates. Finally, we show how to derive a near-optimal solution of the general problem....

  1. The economic production lot size model extended to include more than one production rate

    DEFF Research Database (Denmark)

    Larsen, Christian

    2005-01-01

    production rates should be chosen in the interval between the demand rate and the production rate which minimizes unit production costs, and should be used in an increasing order. Then, given the production rates, we derive closed-form expressions for all optimal runtimes as well as the minimum average cost......We study an extension of the economic production lot size model, where more than one production rate can be used during a cycle. Moreover, the production rates, as well as their corresponding runtimes are decision variables. We decompose the problem into two subproblems. First, we show that all....... This analysis reveals that it is the size of the setup cost that determines the need for being able to use several production rates. We also show how to derive a near-optimal solution of the general problem....

  2. ENTROPY PRODUCTION RATE OF THE MINIMAL DIFFUSION PROCESS

    Institute of Scientific and Technical Information of China (English)

    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.

  3. Weak Interaction Neutron Production Rates in Fully Ionized Plasmas

    OpenAIRE

    Widom, A.; Swain, J.; Srivastava, Y. N.

    2013-01-01

    Employing the weak interaction reaction wherein a heavy electron is captured by a proton to produce a neutron and a neutrino, the neutron production rate for neutral hydrogen gases and for fully ionized plasmas is computed. Using the Coulomb atomic bound state wave functions of a neutral hydrogen gas, our production rate results are in agreement with recent estimates by Maiani {\\it et al}. Using Coulomb scattering state wave functions for the fully ionized plasma, we find a substantially enha...

  4. Higher Export Tax Rates for Copper Related Products

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    <正>According to a notice published by the Finance Ministry, the State Council’s Customs Tax Regulation Committee has decided to make some adjustments on the export tax rates for some copper related products. The notice says that in order to control the export products re-

  5. Stocking rate effects in a tilapia biofloc production system

    Science.gov (United States)

    Production efficiency is improved when the culture organism can grow rapidly to the desired target weight. Stocking rate is known to affect fish growth, but little information is available for tilapia grown in a biofloc technology (BFT) production system. The objective of this study was to quantify ...

  6. On Homogeneous Production Functions with Proportional Marginal Rate of Substitution

    Directory of Open Access Journals (Sweden)

    Alina Daniela Vîlcu

    2013-01-01

    Full Text Available We completely classify homogeneous production functions with proportional marginal rate of substitution and with constant elasticity of labor and capital, respectively. These classifications generalize some recent results of C. A. Ioan and G. Ioan (2011 concerning the sum production function.

  7. Kijkwijzer: The Dutch rating system for audiovisual productions

    NARCIS (Netherlands)

    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

  8. Maximizing production rates of the Linde Hampson machine

    Science.gov (United States)

    Maytal, B.-Z.

    2006-01-01

    In contrast to the ideal case of unlimited size recuperator, any real Linde-Hampson machine of finite size recuperator can be optimized to reach the extreme rates of performance. The group of cryocoolers sharing the same size recuperator is optimized in a closed form by determining the corresponding flow rate which maximizes its rate of cold production. For a similar group of liquefiers an optimal flow rate is derived to maximize the rate of production of liquid cryogen. The group of cryocoolers sharing a constant and given flow rate is optimized by shortening the recuperator for reaching a maximum compactness measured by the cooling power per unit size of the recuperator. The optimum conditions are developed for nitrogen and argon. The relevance of this analysis is discussed in the context of practice of fast cooldown Joule-Thomson cryocooling.

  9. 36Cl terrestrial cosmogenic nuclide dating suggests Late Pleistocene to Early Holocene mass movements on the south face of Aconcagua mountain and in the Las Cuevas–Horcones valleys, Central Andes, Argentina

    OpenAIRE

    Hermanns, Reginald; Fauque, Luis; Wilson, Carlos GW

    2014-01-01

    The morphology, sedimentology and mineralogy of deposits that previously had been associated with glacial advances (the Penitentes, Horcones and Almacenes drifts) were reinvestigated and dated using the terrestrial cosmogenic nuclide (TCN) 36Cl. These results indicate that the deposits previously associated with the Horcones and Almacenes drifts are actually deposits of a rock slope failure from the southern face of Aconcagua mountain forming a debris–ice avalanche that were deposited 10 490±...

  10. Porphyroblast crystallization kinetics: the role of the nutrient production rate

    DEFF Research Database (Denmark)

    Schwarz, Jens-Oliver; Engi, Martin; Berger, Alfons

    2011-01-01

    , such as grain size distributions. In turn, data on porphyroblast textures for natural samples are used to infer which mechanism dominated during their formation. Whereas previous models assume that the rate-limiting step for a porphyroblast producing reaction is either transport or growth, the model advanced...... in this study considers the production of nutrients for porphyroblasts as a potentially rate-limiting factor. This production reflects the breakdown of (metastable) reactants, which at a specific pressure (P) and temperature (T) depends on the bulk composition of the sample. The production of nutrients...... that potentially contribute to the formation of porphyroblasts is computed based on thermodynamic models. The conceptual model assumes that these nutrients feed into some intergranular medium, and products form by nutrient consumption from that medium, with rates depending on reaction affinity. For any sequence...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Refinement of the Air Force Systems Command Production Rate Model

    Science.gov (United States)

    1989-09-01

    the recommended modified formulations. The relationship between production rate and production ratio has a definite influence on the model’s ability to...1984 7 36 21.954 370.00 1985 8 48 21.017 412.00 A- 3 Table A.2.8 F-15E Cost/Quantity Data Fiscal Year Lot Quntit Recurring Unit Cost LPP 1986 1 60

  13. Drill-in fluid reduces formation damage, increases production rates

    Energy Technology Data Exchange (ETDEWEB)

    Hands, N. [Nederlandse Aardolie Maatschappij B.V., Velsen (Netherlands); Kowbel, K. [Ensco International/NAM, Assen (Netherlands); Maikranz, S. [M-I LLC, Houston, TX (United States); Nouris, R. [M-I LLC, Velsen (Netherlands)

    1998-07-13

    A sodium formate drill-in fluid system reduced formation damage, resulting in better-than-expected production rates for an off-shore Dutch development well. Programmed to optimize production capacity and reservoir drainage from a Rotliegend sandstone gas discovery, the 5-7/8-in. subhorizontal production interval was drilled and completed barefoot with a unique, rheologically engineered sodium formate drill-in fluid system. The new system, consisting of a sodium formate (NaCOOH) brine as the base fluid and properly sized calcium carbonate as the formation-bridging agent, was selected on the basis of its well-documented record in reducing solids impairment and formation damage in similar sandstone structures in Germany. The system was engineered around the low-shear-rate viscosity (LSRV) concept, designed to provide exceptional rheological properties. After describing the drilling program, the paper gives results on the drilling and completion.

  14. 5 CFR 532.253 - Special rates or rate ranges for leader, supervisory, and production facilitating positions.

    Science.gov (United States)

    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,...

  15. Automated Production of High Rep Rate Foam Targets

    Science.gov (United States)

    Hall, F.; Spindloe, C.; Haddock, D.; Tolley, M.; Nazarov, W.

    2016-04-01

    Manufacturing low density targets in the numbers needed for high rep rate experiments is highly challenging. This report summarises advances from manual production to semiautomated and the improvements that follow both in terms of production time and target uniformity. The production process is described and shown to be improved by the integration of an xyz robot with dispensing capabilities. Results are obtained from manual and semiautomated production runs and compared. The variance in the foam thickness is reduced significantly which should decrease experimental variation due to target parameters and could allow for whole batches to be characterised by the measurement of a few samples. The work applies to both foil backed and free standing foam targets.

  16. Modeling Electric Discharges with Entropy Production Rate Principles

    Directory of Open Access Journals (Sweden)

    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.

  17. Developing ratings for food products: lessons learned from media rating systems.

    Science.gov (United States)

    Kunkel, Dale; McKinley, Christopher

    2007-01-01

    Children regularly consume low-nutrient, high-calorie food that is not consistent with a healthful diet, contributing to an increasing epidemic of overweight and obesity. Among the multiple causes of this problem is the food industry's emphasis on marketing calorie-dense food products to children. The Institute of Medicine (IOM) has recommended that industry adopt a uniform system of simplified food ratings to convey the nutritional qualities of food in a manner that is understandable and appealing to children and youth. This report analyzes the need for such a system in a food marketing environment that increasingly identifies healthful products for the consumer in inconsistent fashion. It considers evidence regarding current usage of food labeling and draws parallels with media rating systems in discussing the prospects for a uniform food rating system that would accomplish the IOM's objective.

  18. The use of multiple probe molecules for the study of the acid-base properties of aluminium hydroxyfluoride having the hexagonal tungsten bronze structure: FTIR and [36Cl] radiotracer studies.

    Science.gov (United States)

    Dambournet, Damien; Leclerc, Hervé; Vimont, Alexandre; Lavalley, Jean-Claude; Nickkho-Amiry, Mahmood; Daturi, Marco; Winfield, John M

    2009-03-07

    The combination of several probe molecules has enabled the construction of a detailed picture of the surface of aluminium hydroxyl fluoride, AlF(2.6)(OH)(0.4), which has the hexagonal tungsten bronze (HTB) structure. Using pyridine as a probe leads to features at 1628 cm(-1), ascribed to very strong Lewis acid sites, and at 1620-1623 cm(-1), which is the result of several different types of Lewis sites. This heterogeneity is indicated also from CO adsorption at 100 K; the presence of five different types of Lewis site is deduced and is suggested to arise from the hydroxylated environment. Brønsted acid sites of medium strength are indicated by adsorption of lutidine and CO. Adsorption of lutidine occurs at OH groups, which are exposed at the surface and CO reveals that these OH groups have a single environment that can be correlated with their specific location inside the bulk, assuming that the surface OH group may reflect the bulk OH periodicity. A correlation between the data obtained from CO and pyridine molecules has been established using co-adsorption experiments, which also highlight the inductive effect produced by pyridine. Adsorption of the strong Brønsted acid, anhydrous hydrogen chloride, detected by monitoring the beta(-) emission of [(36)Cl]-HCl at the surface, indicates that surface hydroxyl groups can behave also as a Brønsted base and that H(2)O-HCl interactions, either within the hexagonal channels or at the surface are possible. Finally, the formation of strongly bound H(36)Cl as a result of the room temperature dehydrochlorination of [(36)Cl]-labelled tert-butyl chloride provides additional evidence that HTB-AlF(2.6)(OH)(0.4) can behave as a Lewis acid.

  19. Production Rate of Cosmogenic 10Be in Magnetite

    Science.gov (United States)

    Granger, D. E.; Rogers, H. E.; Riebe, C. S.; Lifton, N. A.

    2013-12-01

    Cosmogenic 10Be is widely used for determining exposure ages, soil production rates, and catchment-wide erosion rates. To date, measurements have been almost exclusively in the mineral quartz (SiO2), which is resistant to weathering and easily cleaned of meteoric 10Be contamination. However, this limits the method to quartz-bearing rocks and requires specialized laboratories due to the need for large quantities of hydrofluoric acid (HF). Here, we present initial results for 10Be production in the mineral magnetite (Fe3O4). Magnetite offers several advantages over quartz; it is (1) present in mafic rocks, (2) easily collected in the field, (3) quickly and easily separated in the lab, and (4) digested without HF. In addition, 10Be can be measured in both detrital quartz and magnetite from the same catchment to yield information about the intensity of chemical weathering (Rogers et al., this conference). The 10Be production rate in magnetite relative to quartz was determined for a granitic boulder from Mt. Evans, Colorado, USA. The boulder was crushed and homogenized to facilitate production rate comparisons among various minerals. We separated magnetite using a combination of hand magnets, froth flotation, and a variety of selective chemical dissolutions in dithionite-citrate-bicarbonate solution, 5% nitric acid (HNO3) and 1% HF/HNO3. Six aliquots of magnetite were analyzed for 10Be and compared to quartz. Three aliquots that were not exposed to 1% HF/HNO3 were contaminated with meteoric 10Be, probably associated with residual mica. Three aliquots that were exposed to 1% HF/HNO3 treatments agreed to within 2% measurement uncertainty. Our preliminary results indicate that the relative production rate by mass of 10Be in magnetite and quartz is 0.462 × 0.012. Our results are similar to theoretically predicted values. Recently updated excitation functions for neutron and proton spallation reactions allow us to partition 10Be production in quartz and magnetite among

  20. Production rate calculations for a secondary beam facility

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Reedy, R.C., E-mail: reedy@psi.edu

    2015-10-15

    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.

  2. Production rates of cosmogenic nuclei on the lunar surface

    Science.gov (United States)

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

    2014-07-01

    A physical model for Geant4-based simulation of the galactic cosmic ray (GCR) particles' interaction with the lunar surface matter has been developed to investigate the production rates of cosmogenic nuclei. In this model the GCRs, mainly very high energy protons and α particles, bombard the surface of the Moon and produce many secondary particles, such as protons and neutrons. The energies of protons and neutrons at different depths are recorded and saved as ROOT files, and the analytical expressions for the differential proton and neutron fluxes are obtained through the best-fit procedure using ROOT software. To test the validity of this model, we calculate the production rates of the long-lived nuclei 10Be and 26Al in the Apollo 15 long drill core by combining the above differential fluxes and the newly evaluated spallation reaction cross sections. Our numerical results show that the theoretical production rates agree quite well with the measured data, which means that this model works well. Therefore, it can be expected that this model can be used to investigate the cosmogenic nuclei in future lunar samples returned by the Chinese lunar exploration program and can be extended to study other objects, such as meteorites and the Earth's atmosphere.

  3. Cosmogenic Nuclei Production Rate on the Lunar Surface

    CERN Document Server

    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...

  4. Copepod egg production, moulting and growth rates and secondary production in the Skagerrak in August 1988

    DEFF Research Database (Denmark)

    Peterson, W.T.; Tiselius, P.; Kiørboe, Thomas

    1991-01-01

    Measurements of hydrography, chlorophyll, moulting rates of juvenile copepods and egg production rates of adult female copepods were made at eight stations along a transect across the Skagerrak. The goals of the study were to determine (i) if there were correlations between spatial variations in ...

  5. 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

    Energy Technology Data Exchange (ETDEWEB)

    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

  6. Pore-water mobility: Distribution of {delta}{sup 37}Cl, {sup 36}Cl/Cl, {sup 129}I/{sup 127}I and dissolved {sup 4}He concentration in the core drilled in the Mobara gas field, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Mahara, Yasunori, E-mail: mahara@rri.kyoto-u.ac.jp [Reactor Research Institute, Kyoto University, 2-chome, Asashiro-nishi, Kumatori, Osaka 590-0494 (Japan); Ohta, Tomoko [Reactor Research Institute, Kyoto University, 2-chome, Asashiro-nishi, Kumatori, Osaka 590-0494 (Japan); Tokunaga, Tomochika [Dept. Environmental Systems, School of Frontier Sciences, University of Tokyo, Kashiwa-no-ha 5-1-5, Kashiwa, Chiba 277-8563 (Japan); Matsuzaki, Hiroyuki [Dept. Nuclear Engineering and Management, School of Engineering, University of Tokyo, Yayoi 2-11-16, Bunkyou, Tokyo 113-0032 (Japan); Nagao, Keisuke [Laboratory for Earthquake Chemistry, Graduate School of Science, University of Tokyo, Honngo, Bunkyou, Tokyo 113-0033 (Japan); Nakata, Eiji; Miyamoto, Yuki [Central Research Institute of Electric Power Industry, Abiko 1646, Abiko, Chiba 270-1194 (Japan); Kubota, Takumi [Reactor Research Institute, Kyoto University, 2-chome, Asashiro-nishi, Kumatori, Osaka 590-0494 (Japan)

    2013-01-15

    We measured {sup 36}Cl/Cl and {sup 129}I/{sup 127}I isotope ratios, dissolved {sup 4}He concentrations, and {delta}{sup 37}Cl to estimate the residence time and flow characteristics of pore water in rocks of the Kazusa Group in the Mobara gas field, Japan. We deduced a residence time of 0.28-0.85 Ma for the pore water, based on a secular equilibrium value of 7.05 {+-} 1.58 Multiplication-Sign 10{sup -15} for the {sup 36}Cl/Cl ratio in Pleistocene strata of the gas field. Furthermore, the concentration of {sup 4}He corrected by the solubility equilibrium model in the pore water indicated that residence times varied from 0.09 to 0.62 Ma from the depth of 642 to the depth of 1742 m in the core drilled in the gas field. The pore-water dating results have insignificant differences between the ages of the Kazusa Group formations, compared with the iodine ages from {sup 129}I/{sup 127}I ratio. Variations of {delta}{sup 37}Cl in the pore water suggested that mass transport in rocks of the Kazusa Group was dominantly controlled by diffusion.

  7. 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

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    CERN Document Server

    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...

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

    Science.gov (United States)

    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.

  10. Neutrons in the moon. [neutron flux and production rate calculations

    Science.gov (United States)

    Kornblum, J. J.; Fireman, E. L.; Levine, M.; Aronson, A.

    1973-01-01

    Neutron fluxes for energies between 15 MeV and thermal at depths of 0 to 300 g/sq cm in the moon are calculated by the discrete ordinate mathod with the ANISN code. With the energy spectrum of Lingenfelter et al. (1972). A total neutron-production rate for the moon of 26 plus or minus neutrons/sq cm sec is determined from the Ar-37 activity measurements in the Apollo 16 drill string, which are found to have a depth dependence in accordance with a neutron source function that decreases exponentially with an attenuation length of 155 g/sq cm.

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

    Directory of Open Access Journals (Sweden)

    Jennifer Lin

    2013-01-01

    Full Text Available 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 previous study, we propose a corrected infinite planning horizon inventory model for the first replenishment cycle. Second, while investigating the optimal solution for the minimization problem, we found that the infinite planning horizon should not be applied when dealing with an exponentially decreasing demand. Third, we developed a new production inventory model under a finite planning horizon for practitioners. Numerical examples are provided to support our findings.

  12. Calculation of in-target production rates for radioactive isotope beam production at TRIUMF

    Science.gov (United States)

    Garcia, Fatima; Andreoiu, Corina; Kunz, Peter; Laxdal, Aurelia

    2016-09-01

    Rare Isotope Beam (RIB) facilities around the world, such as TRIUMF, work towards development of new target materials to generate exotic species. Access to these rare radioactive isotopes is key for applications in nuclear medicine, astrophysics and fundamental nuclear science. To better understand production from these and other materials, we have built a computer simulation of the RIB targets used at the TRIUMF Isotope Separation and ACceleration (ISAC) facility, to support new target material development. Built at Simon Fraser University, the simulation runs in the GEANT4 nuclear transport toolkit, and can simulate the production rate of isotopes from a given set of beam and target characteristics. The simulation models the bombardment of a production target by an incident high-energy proton beam and calculates isotope in-target production rates different nuclear reactions. Results from the simulation will be presented, along with an evaluation of various nuclear reaction models and a experimentally determined RIB yields at the ISAC Yield Station.

  13. Enhancing microalgal photosynthesis and productivity in wastewater treatment high rate algal ponds for biofuel production.

    Science.gov (United States)

    Sutherland, Donna L; Howard-Williams, Clive; Turnbull, Matthew H; Broady, Paul A; Craggs, Rupert J

    2015-05-01

    With microalgal biofuels currently receiving much attention, there has been renewed interest in the combined use of high rate algal ponds (HRAP) for wastewater treatment and biofuel production. This combined use of HRAPs is considered to be an economically feasible option for biofuel production, however, increased microalgal productivity and nutrient removal together with reduced capital costs are needed before it can be commercially viable. Despite HRAPs being an established technology, microalgal photosynthesis and productivity is still limited in these ponds and is well below the theoretical maximum. This paper critically evaluates the parameters that limit microalgal light absorption and photosynthesis in wastewater HRAPs and examines biological, chemical and physical options for improving light absorption and utilisation, with the view of enhancing biomass production and nutrient removal.

  14. The mechanics of granitoid systems and maximum entropy production rates.

    Science.gov (United States)

    Hobbs, Bruce E; Ord, Alison

    2010-01-13

    A model for the formation of granitoid systems is developed involving melt production spatially below a rising isotherm that defines melt initiation. Production of the melt volumes necessary to form granitoid complexes within 10(4)-10(7) years demands control of the isotherm velocity by melt advection. This velocity is one control on the melt flux generated spatially just above the melt isotherm, which is the control valve for the behaviour of the complete granitoid system. Melt transport occurs in conduits initiated as sheets or tubes comprising melt inclusions arising from Gurson-Tvergaard constitutive behaviour. Such conduits appear as leucosomes parallel to lineations and foliations, and ductile and brittle dykes. The melt flux generated at the melt isotherm controls the position of the melt solidus isotherm and hence the physical height of the Transport/Emplacement Zone. A conduit width-selection process, driven by changes in melt viscosity and constitutive behaviour, operates within the Transport Zone to progressively increase the width of apertures upwards. Melt can also be driven horizontally by gradients in topography; these horizontal fluxes can be similar in magnitude to vertical fluxes. Fluxes induced by deformation can compete with both buoyancy and topographic-driven flow over all length scales and results locally in transient 'ponds' of melt. Pluton emplacement is controlled by the transition in constitutive behaviour of the melt/magma from elastic-viscous at high temperatures to elastic-plastic-viscous approaching the melt solidus enabling finite thickness plutons to develop. The system involves coupled feedback processes that grow at the expense of heat supplied to the system and compete with melt advection. The result is that limits are placed on the size and time scale of the system. Optimal characteristics of the system coincide with a state of maximum entropy production rate.

  15. Distribution, identification, and quantification of residues after treatment of ready-to-eat salami with 36Cl-labeled or nonlabeled chlorine dioxide gas

    Science.gov (United States)

    Chlorine dioxide gas actively eliminates a variety of food-borne pathogens and rot organisms, including Listeria monocytogenes on food and food preparation surfaces. However the disposition and fate of chlorine dioxide gas on ready-to-eat meat products has not been previously described. When ready-t...

  16. Analysis of two production inventory systems with buffer, retrials and different production rates

    Science.gov (United States)

    Jose, K. P.; Nair, Salini S.

    2017-02-01

    This paper considers the comparison of two ( {s,S} ) production inventory systems with retrials of unsatisfied customers. The time for producing and adding each item to the inventory is exponentially distributed with rate β . However, a production rate α β higher than β is used at the beginning of the production. The higher production rate will reduce customers' loss when inventory level approaches zero. The demand from customers is according to a Poisson process. Service times are exponentially distributed. Upon arrival, the customers enter into a buffer of finite capacity. An arriving customer, who finds the buffer full, moves to an orbit. They can retry from there and inter-retrial times are exponentially distributed. The two models differ in the capacity of the buffer. The aim is to find the minimum value of total cost by varying different parameters and compare the efficiency of the models. The optimum value of α corresponding to minimum total cost is an important evaluation. Matrix analytic method is used to find an algorithmic solution to the problem. We also provide several numerical or graphical illustrations.

  17. 50 CFR Table 3 to Part 679 - Product Recovery Rates for Groundfish Species and Conversion Rates for Pacific Halibut

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Product Recovery Rates for Groundfish Species and Conversion Rates for Pacific Halibut 3 Table 3 to Part 679 Wildlife and Fisheries FISHERY...) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Table 3 Table 3 to Part 679—Product...

  18. The energy production rate & the generation spectrum of UHECRs

    CERN Document Server

    Katz, Boaz; Waxman, Eli

    2008-01-01

    We derive simple analytic expressions for the flux and spectrum of ultra-high energy cosmic-rays (UHECRs) predicted in models where the CRs are protons produced by extra-Galactic sources. For a power-law scaling of the CR production rate with redshift and energy, d\\dot{n} /dE\\propto E^-\\alpha (1+z)^m, our results are accurate at high energy, E>10^18.7 eV, to better than 15%, providing a simple and straightforward method for inferring d\\dot{n}/dE from the observed flux at E. We show that current measurements of the UHECR spectrum, including the latest Auger data, imply E^2d\\dot{n}/dE(z=0)=(0.45\\pm0.15)(\\alpha-1) 10^44 erg Mpc^-3 yr^-1 at E<10^19.5 eV with \\alpha roughly confined to 2\\lesseq\\alpha<2.7. The uncertainty is dominated by the systematic and statistic errors in the experimental determination of individual CR event energy, (\\Delta E/E)_{sys}~(\\Delta E/E)_{stat} ~20%. At lower energy, d\\dot{n}/dE is uncertain due to the unknown Galactic contribution. Simple models in which \\alpha\\simeq 2 and the ...

  19. 30 CFR 250.1159 - May the Regional Supervisor limit my well or reservoir production rates?

    Science.gov (United States)

    2010-07-01

    ... based on well tests and any limitations imposed by well and surface equipment, sand production... reservoir production rates? 250.1159 Section 250.1159 Mineral Resources MINERALS MANAGEMENT SERVICE... Gas Production Requirements Production Rates § 250.1159 May the Regional Supervisor limit my well...

  20. Apply the Nuclear Bomb Pulse of 36Cl to Quantify Groundwater Recharge%应用36Cl核爆脉冲峰测量包气带水补给

    Institute of Scientific and Technical Information of China (English)

    刘莉; 马东升

    2007-01-01

    包气带中地下水运动研究是一个比较复杂的问题.传统的地下水动力学方法在解决这一问题有一定局限性,而利用同位素示踪研究包气带中地下水运动却有其独特的优越性.36Cl是氯的一种放射性同位素,来源有大气、岩石圈及人工三个方面.由于全球大气层核试验,产生了大量36Cl,形成了明显的核爆脉冲峰.简要论述了全球大气层核试验,特别是近海的核爆炸与36Cl沉降的关系,叙述应用36Cl核爆脉冲峰测量包气带地下水补给的研究进展.

  1. r-PROCESS LANTHANIDE PRODUCTION AND HEATING RATES IN KILONOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Lippuner, Jonas; Roberts, Luke F., E-mail: jlippuner@tapir.caltech.edu [TAPIR, Walter Burke Institute for Theoretical Physics, California Institute of Technology, MC 350-17, 1200 E California Boulevard, Pasadena CA 91125 (United States)

    2015-12-20

    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 ejecta, which determines the local heating rate from nuclear decays and the opacity. Kasen et al. and Tanaka and Hotokezaka 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{sub e}, initial specific entropies s, and expansion timescales τ. We find that the ejecta is lanthanide-free for Y{sub e} ≳ 0.22−0.30, depending on s and τ. The heating rate is insensitive to s and τ, but certain, larger values of Y{sub e} lead to reduced heating rates, due to individual nuclides dominating the heating. We calculate approximate light curves with a simplified gray radiative transport scheme. The light curves peak at about a day (week) in the lanthanide-free (-rich) cases. The heating rate does not change much as the ejecta becomes lanthanide-free with increasing Y{sub e}, but the light-curve peak becomes about an order of magnitude brighter because it peaks much earlier when the heating rate is larger. We also provide parametric fits for the heating rates between 0.1 and 100 days, and we provide a simple fit in Y{sub e}, s, and τ to estimate whether or not the ejecta is lanthanide-rich.

  2. An EPQ Model with Unit Production Cost and Set-Up Cost as Functions of Production Rate

    Directory of Open Access Journals (Sweden)

    Behrouz Afshar-Nadjafi

    2013-01-01

    Full Text Available Extensive research has been devoted to economic production quantity (EPQ problem. However, no attention has been paid to problems where unit production and set-up costs must be considered as functions of production rate. In this paper, we address the problem of determining the optimal production quantity and rate of production in which unit production and set-up costs are assumed to be continuous functions of production rate. Based on the traditional economic production quantity (EPQ formula, the cost function associated with this model is proved to be nonconvex and a procedure is proposed to solve this problem. Finally, utility of the model is presented using some numerical examples and the results are analyzed.

  3. The Modeling of Logistics and Coordination of the Rate of Commodities Production with the Rate of their Disposal

    Directory of Open Access Journals (Sweden)

    Sherstennykov Yuriy V.

    2016-08-01

    Full Text Available The economic objective of the modern high-tech enterprise is the optimal expansion of its own market niche and bringing the production capacities in accordance with the current demand for the products. An important role in this respect is played by issues of optimal organization of the enterprise logistics, marketing analysis of the current demand and effective advertising campaign aimed at maximal use of the available production capacity and creation of proper conditions for developing, in particular for increasing the production capacities. The purpose of the article is the elaboration of economic and mathematical models of enterprise production activity taking into account the logistics and market demand; the use of the elaborated model to harmonize the rate of production of everyday commodities with the rate of their disposal. Two variants of the enterprise logistics schemes are analyzed. The influence of the advertising company on expanding the enterprise market niche is studied. A model that allows conducting a detailed study of the influence of market conditions on the pace of sales has been developed. It is appropriate to apply the model for the integrated coordination of the production rate of commodities of everyday demand with the dynamics of flows of commodities and services disposal.

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

    CERN Document Server

    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...

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

    Science.gov (United States)

    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.

  6. High hydrogen production rate of microbial electrolysis cell (MEC) with reduced electrode spacing.

    Science.gov (United States)

    Cheng, Shaoan; Logan, Bruce E

    2011-02-01

    Practical applications of microbial electrolysis cells (MECs) require high hydrogen production rates and a compact reactor. These goals can be achieved by reducing electrode spacing but high surface area anodes are needed. The brush anode MEC with electrode spacing of 2 cm had a higher hydrogen production rate and energy efficiency than an MEC with a flat cathode and a 1-cm electrode spacing. The maximum hydrogen production rate with a 2 cm electrode spacing was 17.8 m(3)/m(3)d at an applied voltage of E(ap)=1 V. Reducing electrode spacing increased hydrogen production rates at the lower applied voltages, but not at the higher (>0.6 V) applied voltages. These results demonstrate that reducing electrode spacing can increase hydrogen production rate, but that the closest electrode spacing do not necessarily produce the highest possible hydrogen production rates.

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  8. Impact of Declining Proposal Success Rates on Scientific Productivity

    CERN Document Server

    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...

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

    DEFF Research Database (Denmark)

    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...

  10. Non-perturbative production rate of photons with a lattice quark propagator: effect of vertex correction

    CERN Document Server

    Kim, Taekwang; Kitazawa, Masakiyo

    2016-01-01

    We analyze the production rate of photons from the thermal medium above the deconfinement temperature with a quark propagator obtained from a lattice QCD numerical simulation. The photon-quark vertex is determined gauge-invariantly, so as to satisfy the Ward-Takahashi identity. The obtained photon production rate shows a suppression compared to perturbative results.

  11. Chain elongation of acetate and ethanol in an upflow anaerobic filter for high rate MCFA production

    NARCIS (Netherlands)

    Grootscholten, T.I.M.; Steinbusch, K.J.J.; Hamelers, H.V.M.; Buisman, C.J.N.

    2013-01-01

    Recently, interest has regained for medium chain fatty acids (MCFAs) as a low cost feedstock for bio-based chemical and fuel production processes. To become cost-effective, the volumetric MCFA production rate by chain elongation should increase to comparable rates of other fermentation processes. We

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

    Directory of Open Access Journals (Sweden)

    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.

  13. Outdoor pilot-scale production of Nannochloropsis gaditana: influence of culture parameters and lipid production rates in tubular photobioreactors.

    Science.gov (United States)

    San Pedro, A; González-López, C V; Acién, F G; Molina-Grima, E

    2014-10-01

    This work studied outdoor pilot scale production of Nannochloropsis gaditana in tubular photobioreactors. The growth and biomass composition of the strain were studied under different culture strategies: continuous-mode (varying nutrient supply and dilution rate) and two-stage cultures aiming lipid enhancement. Besides, parameters such as irradiance, specific nitrate input and dilution rate were used to obtain models predicting growth, lipid and fatty acids production rates. The range of optimum dilution rate was 0.31-0.351/day with maximum biomass, lipid and fatty acids productivities of 590, 110 and 66.8 mg/l day, respectively. Nitrate limitation led to an increase in lipid and fatty acids contents (from 20.5% to 38.0% and from 16.9% to 23.5%, respectively). Two-stage culture strategy provided similar fatty acids productivities (56.4 mg/l day) but the neutral lipids content was doubled.

  14. The Single-Vendor-Single-Buyer Integrated Production-Shipment Model with Stock Dependent Demand Rate

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the integrated production-shipment models for the single-vendor-single-buyer system presented hitherto, thedemand rate of items is treated as a constant. However, many researchers have observed that the presence of morequantities of the same product tends to attract more customers. This suggests that the demand rate should depend on thestock level. This paper presents a single-vendor-single-buyer production-shipment model with the stock dependentdemand rate, based on the demand rate linearly depending upon the stock level at any instant of time.

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

    Institute of Scientific and Technical Information of China (English)

    DING Hui; LUO Liao-Fu; LIN Hao

    2011-01-01

    According to the chemical kinetic model of lysogeny/lysis switch in Escherichia coli (E. coli) intected 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.

  16. High Acetic Acid Production Rate Obtained by Microbial Electrosynthesis from Carbon Dioxide

    NARCIS (Netherlands)

    Jourdin, Ludovic; Grieger, Timothy; Monetti, Juliette; Flexer, Victoria; Freguia, Stefano; Lu, Yang; Chen, Jun; Romano, Mark; Wallace, Gordon G.; Keller, Jurg

    2015-01-01

    High product specificity and production rate are regarded as key success parameters for large-scale applicability of a (bio)chemical reaction technology. Here, we report a significant performance enhancement in acetate formation from CO2, reaching comparable productivity levels as in i

  17. 78 FR 41129 - Market Test of Experimental Product - International Merchandise Return Service-Non-Published Rates

    Science.gov (United States)

    2013-07-09

    ... 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. DATES... will begin a market test of its International Merchandise Return Service (IMRS) Non-published Rate...

  18. Chlorine-36 in Water, Snow, and Mid-Latitude Glacial Ice of North America: Meteoric and Weapons-Tests Production in the Vicinity of the Idaho National Engineering and Environmental Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    L. DeWayne; J. R. Green (USGS); S. Vogt, P. Sharma (Purdue University); S. K. Frape (University of Waterloo); S. N. Davis (University of Arizona); G. L. Cottrell (USGS)

    1999-01-01

    Measurements of chlorine-36 (36Cl) were made for 64 water, snow, and glacial-ice and -runoff samples to determine the meteoric and weapons-tests-produced concentrations and fluxes of this radionuclide at mid-latitudes in North America. The results will facilitate the use of 36Cl as a hydrogeologic tracer at the Idaho National Engineering and Environmental Laboratory (INEEL). This information was used to estimate meteoric and weapons-tests contributions of this nuclide to environmental inventories at and near the INEEL. The data presented in this report suggest a meteoric source 36Cl for environmental samples collected in southeastern Idaho and western Wyoming if the concentration is less than 1 x 10 7 atoms/L. Additionally, concentrations in water, snow, or glacial ice between 1 x 10 7 and 1 x 10 8 atoms/L may be indicative of a weapons-tests component from peak 36Cl production in the late 1950s. Chlorine-36 concentrations between 1 x 10 8 and 1 x 10 9 atoms/L may be representative of re-suspension of weapons-tests fallout airborne disposal of 36Cl from the INTEC, or evapotranspiration. It was concluded from the water, snow, and glacial data presented here that concentrations of 36Cl measured in environmental samples at the INEEL larger than 1 x 10 9 atoms/L can be attributed to waste-disposal practices.

  19. Free energy and entropy production rate for a Brownian particle that walks on overdamped medium

    Science.gov (United States)

    Taye, Mesfin Asfaw

    2016-09-01

    We derive general expressions for the free energy, entropy production, and entropy extraction rates for a Brownian particle that walks in a viscous medium where the dynamics of its motion is governed by the Langevin equation. It is shown that, when the system is out of equilibrium, it constantly produces entropy and at the same time extracts entropy out of the system. Its entropy production and extraction rates decrease in time and saturate to a constant value. In the long-time limit, the rate of entropy production balances the rate of entropy extraction and, at equilibrium, both entropy production and extraction rates become zero. Moreover, considering different model systems, not only do we investigate how various thermodynamic quantities behave in time but also we discuss the fluctuation theorem in detail.

  20. Exact solutions for the entropy production rate of several irreversible processes.

    Science.gov (United States)

    Ross, John; Vlad, Marcel O

    2005-11-24

    We investigate thermal conduction described by Newton's law of cooling and by Fourier's transport equation and chemical reactions based on mass action kinetics where we detail a simple example of a reaction mechanism with one intermediate. In these cases we derive exact expressions for the entropy production rate and its differential. We show that at a stationary state the entropy production rate is an extremum if and only if the stationary state is a state of thermodynamic equilibrium. These results are exact and independent of any expansions of the entropy production rate. In the case of thermal conduction we compare our exact approach with the conventional approach based on the expansion of the entropy production rate near equilibrium. If we expand the entropy production rate in a series and keep terms up to the third order in the deviation variables and then differentiate, we find out that the entropy production rate is not an extremum at a nonequilibrium steady state. If there is a strict proportionality between fluxes and forces, then the entropy production rate is an extremum at the stationary state even if the stationary state is far away from equilibrium.

  1. Calculation of the Solar Activity Effect on the Production Rate of Cosmogenic Radiocarbon in Polar Ice

    CERN Document Server

    Nesterenok, A V

    2012-01-01

    The propagation of cosmic rays in the Earth's atmosphere is simulated. Calculations of the omnidirectional differential flux of neutrons for different solar activity levels are presented. The solar activity effect on the production rate of cosmogenic radiocarbon by the nuclear-interacting and muon components of cosmic rays in polar ice is studied. It has been obtained that the $^{14}C$ production rate in ice by the cosmic ray nuclear-interacting component is lower or higher than the average value by 30% during periods of solar activity maxima or minima, respectively. Calculations of the altitudinal dependence of the radiocarbon production rate in ice by the cosmic ray components are illustrated.

  2. An integrated supply chain model for the perishable items with fuzzy production rate and fuzzy demand rate

    Directory of Open Access Journals (Sweden)

    Singh Chaman

    2011-01-01

    Full Text Available In the changing market scenario, supply chain management is getting phenomenal importance amongst researchers. Studies on supply chain management have emphasized the importance of a long-term strategic relationship between the manufacturer, distributor and retailer. In the present paper, a model has been developed by assuming that the demand rate and production rate as triangular fuzzy numbers and items deteriorate at a constant rate. The expressions for the average inventory cost are obtained both in crisp and fuzzy sense. The fuzzy model is defuzzified using the fuzzy extension principle, and its optimization with respect to the decision variable is also carried out. Finally, an example is given to illustrate the model and sensitivity analysis is performed to study the effect of parameters.

  3. Rapid rates of soil production in the western Southern Alps, New Zealand

    Science.gov (United States)

    Larsen, I. J.; Almond, P. C.; Eger, A.; Stone, J. O.; Malcolm, B.; Montgomery, D. R.

    2012-12-01

    Quantifying rates of soil production is necessary for determining the relative magnitude of the processes that drive the evolution of mountain topography and for assessing proposed links among tectonic uplift, erosion, weathering, and global biogeochemical cycles. However, little is known about the role soil production plays in the denudation of rapidly uplifting mountains. We addressed this problem by sampling soil and river sediment from five catchments in the rapidly uplifting and high rainfall portion of the western Southern Alps, New Zealand. Soils were sampled from ridgetops with subalpine forest and dense alpine shrubland vegetation. Results from 11 measurements of in situ-produced 10Be in soils from three catchments show that rock is rapidly converted to soil, with the highest measured rate approaching 2 mm yr-1. Soil production rates at two of the ridgetops decline exponentially as soil depth increases, consistent with previously proposed soil production functions. The third site exhibits an ambiguous soil production rate-depth relationship. The y-intercepts, or maximum predicted soil production rate where the soil depth is equal to zero, at the sites with well-defined soil production functions are 7-9 times greater than those in other tectonically-active mountains and 1-2 orders of magnitude greater than values from drier and more tectonically-quiescent landscapes, indicating that rock can be converted to soil at substantially higher rates than previously recognized. The maximum predicted soil production rate values are 1.5 to 2.5 times lower than watershed-scale denudation rates inferred from in situ 10Be concentrations in stream sediment, indicating that soil production rates approach, but do not reach catchment-averaged values, which also reflect denudation by bedrock landslides. Ongoing work on additional samples will lead to a refinement of the soil production functions and provide rates for two additional sites. In-progress measurement of zirconium

  4. Lorentz Invariance at Finite Temperature and Its Effect on Production Rate and Equation of State

    Institute of Scientific and Technical Information of China (English)

    HE Lian-Yi; ZHUANG Peng-Fei

    2004-01-01

    The effect of Lorentz invariance breaking on the production rate and the equation of state at finite temperature is investigated in the frame of φ3 theory. The invariance breaking significantly changes the off-shell degree at high temperatures.

  5. A nonlabeled method to evaluate cortisol production rate by modeling plasma CBG-free cortisol disposition

    OpenAIRE

    Picard-Hagen, Nicole; Gayrard-Troy, Véronique,; Alvinerie, Michel; Smeyers, Hélène; Ricou, Raphael; Bousquet-Mélou, Alain; Toutain, Pierre-Louis

    2001-01-01

    This study aimed to develop a nonlabeled method for the measurement of cortisol production rate to evaluate adrenal function. The cortisol production rate determination requires that of cortisol clearance, which is not a parameter but a variable resulting from the saturable binding of cortisol to corticosteroid-binding globulin (CBG). Our method is based on evaluation of the plasma clearance of the CBG-free cortisol fraction. This parameter was evaluated from a pharmacokinetic model of total ...

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

    Energy Technology Data Exchange (ETDEWEB)

    L. D. Cecil; L. L. Knobel; J. R. Green (USGS); S. K. Frape (University of Waterloo)

    2000-06-01

    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.

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

    Directory of Open Access Journals (Sweden)

    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

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

    DEFF Research Database (Denmark)

    Rodes Lopez, Roberto; Jensen, Jesper Bevensee; Caballero Jambrina, Antonio

    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....

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

    OpenAIRE

    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...

  10. Koppe's Work of 1948: A fundamental for non-equilibrium rate of particle production

    CERN Document Server

    Tawfik, Abdel Nasser

    2013-01-01

    In 1948, Koppe formulated an almost complete recipe for statistical-thermal models including particle production, formation and decay of resonances, temporal and thermal evolution of the interacting system, statistical approaches and equilibrium condition in final state of the nuclear interaction. As the rate of particle production was one of the basic assumptions, recalling Koppe's work would be an essential input to be involved in the statistical prediction of non-equilibrium particle production in recent and future ultra-relativistic collisions.

  11. The Rate for $B\\bbar$ Production Accompanied by a Single Pion

    CERN Document Server

    Randall, Lisa; Randall, Lisa; Sather, Eric

    1993-01-01

    We study the rate for the production of ${B B^\\pm \\pi^\\mp}$, where the sign of the charged pion tags the flavor content of the neutral $B$ meson. We estimate this branching ratio, employing the heavy meson chiral effective theory. We find that at center of mass energy of approximately 12 GeV, a $B$ meson pair should be produced as often with and without an accompanying charged pion. We also calculate two pion production at this center of mass energy, and find that it is negligible, as is the rate for rho production. We consider the implications for CP violation studies. (Invited Talk, 1993 Electroweak Rencontres de Moriond)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    Sanderman, Jonathan; Creamer, Courtney; Baisden, W. Troy; Farrell, Mark; Fallon, Stewart

    2017-01-01

    Devising agricultural management schemes that enhance food security and soil carbon levels is a high priority for many nations. However, the coupling between agricultural productivity, soil carbon stocks and organic matter turnover rates is still unclear. Archived soil samples from four decades of a long-term crop rotation trial were analyzed for soil organic matter (SOM) cycling-relevant properties: C and N content, bulk composition by nuclear magnetic resonance (NMR) spectroscopy, amino sugar content, short-term C bioavailability assays, and long-term C turnover rates by modeling the incorporation of the bomb spike in atmospheric 14C into the soil. After > 40 years under consistent management, topsoil carbon stocks ranged from 14 to 33 Mg C ha-1 and were linearly related to the mean productivity of each treatment. Measurements of SOM composition demonstrated increasing amounts of plant- and microbially derived SOM along the productivity gradient. Under two modeling scenarios, radiocarbon data indicated overall SOM turnover time decreased from 40 to 13 years with increasing productivity - twice the rate of decline predicted from simple steady-state models or static three-pool decay rates of measured C pool distributions. Similarly, the half-life of synthetic root exudates decreased from 30.4 to 21.5 h with increasing productivity, indicating accelerated microbial activity. These findings suggest that there is a direct feedback between accelerated biological activity, carbon cycling rates and rates of carbon stabilization with important implications for how SOM dynamics are represented in models.

  14. Monte Carlo simulation of GCR neutron capture production of cosmogenic nuclides in stony meteorites and lunar surface

    Science.gov (United States)

    KolláR, D.; Michel, R.; Masarik, J.

    2006-03-01

    A purely physical model based on a Monte Carlo simulation of galactic cosmic ray (GCR) particle interaction with meteoroids is used to investigate neutron interactions down to thermal energies. Experimental and/or evaluated excitation functions are used to calculate neutron capture production rates as a function of the size of the meteoroid and the depth below its surface. Presented are the depth profiles of cosmogenic radionuclides 36Cl, 41Ca, 60Co, 59Ni, and 129I for meteoroid radii from 10 cm up to 500 cm and a 2π irradiation. Effects of bulk chemical composition on n-capture processes are studied and discussed for various chondritic and lunar compositions. The mean GCR particle flux over the last 300 ka was determined from the comparison of simulations with measured 41Ca activities in the Apollo 15 drill core. The determined value significantly differs from that obtained using equivalent models of spallation residue production.

  15. Comparison of Heterotrophic Bacterial Production-Rates in Early Spring in the Turbid Estuaries of the Scheldt and the Elbe

    NARCIS (Netherlands)

    Goosen, N.K.; Van Rijswijk, P.; Brockmann, U.

    1995-01-01

    In spring bacterial production rates were estimated by tritiated thymidine incorporation in the turbid estuaries of the rivers Scheldt and Elbe. Bacterial production rates in the Scheldt were 5 times higher than in the Elbe. In the Scheldt bacterial production rates correlated better with the DOC co

  16. Analytical modeling of gas production rate in tight channel sand formation and optimization of artificial fracture.

    Science.gov (United States)

    Wang, Ruifei; Song, Hongqing; Tang, Hewei; Wang, Yuhe; Killough, John; Huang, Gang

    2016-01-01

    Permeability variation in tight channel sand formation makes an important role in gas production. Based on the features of channel sand formation, a mathematical model has been established considering anisotropy of permeability. The analytical solutions were derived for productivity of both vertical wells and vertically fractured wells. Simulation results show that, gas production rate of anisotropic channel sand formation is less than that of isotropic formation. For vertically fractured well, artificial fracture direction, drainage radius, permeability ratio and fracture half-length have considerable influence on production rate. The optimum fracture direction should be deviated less than π/8 from the maximum permeability direction (or the channel direction). In addition, the analytical model was verified by in situ measured data. The research provides theoretical basis for the development of tight channel sand gas reservoirs.

  17. Economic fluctuations in a small economy with two productive sectors under a floating exchange rate regime

    Directory of Open Access Journals (Sweden)

    José Ustorgio Mora Mora

    2013-06-01

    Full Text Available This paper presents a theoretical model of aggregate supply and demand in a small economy with two productive sectors, under a flexible exchange regime and imperfect capital mobility. Only one of the production sectors is assumed to produce an exportable commodity sold at world market prices, while the production of the other sector is assumed to supply the domestic market. This model helps to explain how the impact of both domestic (economic policy, productivity, etc. and foreign (changes in exchange terms shocks is spread. In every case studied, results show that real output increases consistently with those cases postulated by economic theory. Conversely, the effects on the price level, the exchange rate and the real interest rate are ambiguous. In terms of domestic shocks, fiscal or monetary policy may be seen as a way to stabilize or stimulate the economy but the costs involved raise the price level.

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

  19. Variability in root production, phenology, and turnover rate among 12 temperate tree species.

    Science.gov (United States)

    McCormack, M Luke; Adams, Thomas S; Smithwick, Erica A H; Eissenstat, David M

    2014-08-01

    The timing of fine root production and turnover strongly influences both the seasonal potential for soil resource acquisition among competing root systems and the plant fluxes of root carbon into soil pools. However, basic patterns and variability in the rates and timing or fine root production and turnover are generally unknown among perennial plants species. We address this shortfall using a heuristic model relating root phenology to turnover together with three years of minirhizotron observations of root dynamics in 12 temperate tree species grown in a common garden. We specifically investigated how the amount and the timing of root production differ among species and how they impact estimates of fine root turnover. Across the 12 species, there was wide variation in the timing of root production with some species producing a single root flush in early summer and others producing roots either more uniformly over the growing season or in multiple pulses. Additionally, the pattern and timing of root production appeared to be consistent across years for some species but varied in others. Root turnover rate was related to total root production (P phenology. Overall, we suggest that more detailed observations of root phenology and production will improve fidelity of root turnover estimates. Future efforts should link patterns of root phenology and production with whole-plant life history traits and variation in annual and seasonal climate.

  20. Optimisation of fertiliser rates in crop production against energy use indicators

    DEFF Research Database (Denmark)

    Rossner, Helis; Ritz, Christian; Astover, Alar

    2014-01-01

    Optimising mineral nitrogen (N) use in crop production is inevitable target as mineral fertilisers reflectone of the highest inputs both in terms of economy and energy. The aim of the study was to comparethe relationship between the rate of N fertiliser application and different measures of energy.......05) optimisation. Both the new combined indices gave optimum N norms in between the rate ofER an EG. Composted cow manure background did not affect mineral N optimisation significantly. Wesuggest optimisation of mineral N according to bi-dimensional parameters as they capture important fea-tures of production...

  1. The kinematic and microphysical control of lightning rate, extent, and NOX production

    Science.gov (United States)

    Carey, Lawrence D.; Koshak, William; Peterson, Harold; Mecikalski, Retha M.

    2016-07-01

    This study investigates the kinematic and microphysical control of lightning properties, particularly those that may govern the production of nitrogen oxides (NOX = NO + NO2) via lightning (LNOX), such as flash rate, type, and extent. The NASA Lightning Nitrogen Oxides Model (LNOM) is applied to lightning observations following multicell thunderstorms through their lifecycle in a Lagrangian sense over Northern Alabama on 21 May 2012 during the Deep Convective Clouds and Chemistry (DC3) experiment. LNOM provides estimates of flash rate, type, channel length distributions, channel segment altitude distributions (SADs), and LNOX production profiles. The LNOM-derived lightning characteristics and LNOX production are compared to the evolution of radar-inferred updraft and precipitation properties. Intercloud, intracloud (IC) flash SAD comprises a significant fraction of the total (IC + cloud-to-ground [CG]) SAD, while increased CG flash SAD at altitudes >6 km occurs after the simultaneous peaks in several thunderstorm properties (i.e., total [IC + CG] and IC flash rate, graupel volume/mass, convective updraft volume, and maximum updraft speed). At heights 6 km. Graupel volume/mass, updraft volume, and maximum updraft speed are all well correlated to the total flash rate (correlation coefficient, ρ ≥ 0.8) but are less correlated to total flash extent (ρ ≥ 0.6) and total LNOX production (ρ ≥ 0.5). Although LNOM transforms lightning observations into LNOX production values, these values are estimates and are subject to further independent validation.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Indian Academy of Sciences (India)

    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.

  4. Linear extension rates and gross carbonate production of Acropora cervicornis at Coral Gardens, Belize.

    Science.gov (United States)

    Peeling, E.; Greer, L.; Lescinsky, H.; Humston, R.; Wirth, K. R.; Baums, I. B.; Curran, A.

    2014-12-01

    Branching Acropora coral species have fast growth and carbonate production rates, and thus have functioned as important reef-building species throughout the Pleistocene and Holocene. Recently, net carbonate production (kg CaCO3 m-2 year-1) has been recognized as an important measure of reef health, especially when monitoring endangered species, such as Acropora cervicornis. This study examines carbonate production in a thriving population of A. cervicornis at the Coral Gardens reef in Belize. Photographic surveys were conducted along five transects of A. cervicornis-dominated reefs from 2011-2014. Matching photographs from 2013 and 2014 were scaled to 1 m2 and compared to calculate 84 individual A. cervicornis linear extension rates across the reef. Linear extension rates averaged 12.4 cm/yr and were as high as 17 cm/yr in some areas of the reef. Carbonate production was calculated two ways. The first followed the standard procedure of multiplying percent live coral cover, by the linear extension rate and skeletal density. The second used the number of live coral tips per square meter in place of percent live coral multiplied by the average cross-sectional area of the branches. The standard method yielded a carbonate production rate of 113 kg CaCO3 m-2 year-1 for the reef, and the tip method yielded a rate of 6 kg m-2 year-1. We suggest that the tip method is a more accurate measure of production, because A. cervicornis grows primarily from the live tips, with only limited radial growth and resheeting over dead skeleton. While this method omits the contributions of radial growth and resheeting, and is therefore somewhat of an underestimate, our future work will quantify these aspects of growth in a more complete carbonate budget. Still, our estimate suggests a carbonate production rate per unit area of A. cervicornis that is on par with other Caribbean coral species, rather than two orders of magnitude higher as reported by Perry et al (2013). Although gross coral

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Determining eruption ages and erosion rates of Quaternary basaltic volcanism from combined U-series disequilibria and cosmogenic exposure ages

    Science.gov (United States)

    Sims, Kenneth W. W.; Ackert, Robert P., Jr.; Ramos, Frank C.; Sohn, Robert A.; Murrell, Michael T.; Depaolo, Donald J.

    2007-05-01

    We present 238U-230Th -226Ra disequilibria and cosmogenic 3He and 36Cl data for the Bluewater flow of the Zuni-Bandera volcanic field in western New Mexico. The 238U-230Th disequilibria measured on separated groundmass phases yield an internal isochron age of 68 ka (+24/ 20 ka; 2σ). This value cannot be directly compared with surface exposure ages unless erosion rates are known. The apparent (zero erosion) ages determined from both the 3He concentration (47.5 ± 5 ka; 2σ) and the 36Cl concentration (41.2 ± 8.8 ka; 2σ) are significantly younger than the U-Th isochron age. When minimum estimates of surface erosion based on flow morphology are considered, the 3He concentrations indicate a minimum exposure age of 60 ka, in good agreement with the U-Th isochron age, with a minimum erosion rate of 1.7 mm/k.y. and an erosion rate as high as 5 mm/k.y. in other locations. Correcting for erosion has little effect on the model 36Cl age and, as a result, the 36Cl age is significantly younger than the U-Th isochron age and erosion-corrected 3He ages; this discordance is attributed to a lack of closed-system behavior in the 36Cl system. These new ages have local significance for the geochronology of the Zuni-Bandera volcanic field; however, their larger significance is in their applicability to dating Quaternary basalts and quantifying erosion rates.

  7. Combined results on b-hadron production rates, lifetimes, oscillations and semileptonic decays

    CERN Document Server

    Abbaneo, D; Andreev, V; Barberio, E; Battaglia, Marco; Blyth, S; Boix, G; Bourdarios, C; Calvi, M; Checchia, P; Coyle, P; Di Ciaccio, Lucia; Gagnon, P; Hawkings, R; Hayes, O J; Henrard, P; Hessing, T L; Jimack, Martin Paul; 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; Schwick, C; Shepherd-Themistocleous, C H; Simonetto, F; Spagnolo, P; Stocchi, A; Su, D; Usher, T; Weiser, C; Wells, P S; Wicklund, B; Willocq, S

    2000-01-01

    Combined results on b-hadron lifetimes, b-hadron production rates, B&0_d - Bbar^0_d and B^0_s - Bbar^0_s oscillations, the decay width difference between the mass eigenstates of the B^s0_s - Bbar^0_s system, and the values of the CKM

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

    Science.gov (United States)

    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.

  9. Effects of dietary starch content and rate of fermentation on methane production in lactating dairy cows

    NARCIS (Netherlands)

    Hatew, B.; Podesta, S.C.; Laar, van H.; Pellikaan, W.F.; St-Pierre, J.L.; Dijkstra, J.; Bannink, A.

    2015-01-01

    The objective of this study was to investigate the effects of starch varying in rate of fermentation and level of inclusion in the diet in exchange for fiber on methane (CH4) production of dairy cows. Forty Holstein-Friesian lactating dairy cows of which 16 were rumen cannulated were grouped in 10 b

  10. The effect of the composition and production process of concrete on the 222Rn exhalation rate

    NARCIS (Netherlands)

    Jong, P. de; Dijk, W. van; Hulst, J.G.A. van; Heijningen, R.J.J. van

    1997-01-01

    In a series of 18 concrete samples, the influence of several parameters related to composition and production processes on the radon exhalation rate was studied. The investigated parameters were: amount and type of cement, water-cement ratio, curing conditions and curing time, type of aggregates, co

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Dima, Mihai O. [Stanford Univ., CA (United States)

    1997-05-01

    This dissertation presents a study of strange vector meson production, "leading particle" effect and a first direct measurement of the strangeness suppression parameter in hadronic decays of the neutral electroweak boson, Z. 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 ρ 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 "leading particle" 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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  14. Improvement on droplet production rate of ultrasonic - nebulizer in spray pyrolysis process

    Science.gov (United States)

    Panatarani, Camellia; Demen, Tuti Aryati; Men, Liu Kin; Maulana, Dwindra Wilham; Hidayat, Darmawan; Joni, I. Made

    2013-09-01

    Atomization is an important part in Spray Pyrolysis (SP) process which is applied to synthesize submicron or nano sized particles or to deposit thin film. Ultrasonic Nebulizer (UN) is usually use in SP due to its homogeneous droplets production with size between 1-5 μm. The drawback of the UN is low droplets production rate. In this research, we successfully developed a Digital Ultrasonic Nebulizer (DUN) with high droplets production rate using two ultrasonic traducers with applied frequency of 2.4 MHz. The result of DUN atomization was improved 4-6 fold compare to the conventional UN. The DUN also has an additional digital features such as pushbutton, LCD and microcontroller which is allow to set duration and applied voltage.

  15. Potential methane production rates and its carbon isotopic composition from ornithogenic tundra soils in coastal Antarctic

    Institute of Scientific and Technical Information of China (English)

    BAO Tao; ZHU Renbin; BAI Bo; XU Hua

    2016-01-01

    Methane (CH4) is one of important greenhouse gases with chemical activity. The determination of isotopic compositions for CH4 emitted from the soils helps us to understand its production mechanisms. CH4 isotope measurements have been conducted for different types of global terrestrial ecosystems. However, no isotopic data of CH4 have been reported from Antarctic tundra soils. In this paper, ornithogenic soil profiles were collected from four penguin colonies, and potential CH4 production rates and its13C ratio (δ13C) were investigated based upon laboratory incubation experiments. The mean CH4 production rates are highly variable in these soil proifles, ranging from 0.7 to 20.3 μg CH4−C kg−1∙h−1. These ornithogenic soils had high potential production rates of CH4 under ambient air incubation or under N2 incubation, indicating the importance of potential CH4 emissions from penguin colonies. Most of the soil samples had higher δ13C-CH4 under N2 incubation (−39.28%~−43.53%) than under the ambient air incubation (−42.81%~−57.19%). Highly anaerobic conditions were conducive to the production of CH4 enriched in13C, and acetic acid reduction under N2 incubation might be a predominant source for soil CH4production. Overall theδ13C-CH4 showed a signiifcant negative correlation with CH4 production rates in ornithogenic tundra soils under N2 incubation (R2=0.41,p<0.01) or under the ambient air incubation (R2=0.50,p<0.01). Potential CH4 production from ornithogenic soils showed a signiifcant positive correlation with total phosphorus (TP) and NH4+−N contents, pH and soil moisture (Mc), but the δ13C-CH4 showed a signiifcant negative correlation with TP and NH4+−N contents, pH and Mc, indicating that the deposition amount of penguin guano increased potential CH4 production rates from tundra soils, but decreased the δ13C-CH4. The CH4 emissions from the ornithogenic soils affect carbon isotopic compositions of atmospheric CH4in coastal Antarctica.

  16. The local energy production rates of GRB photons and of UHECRs

    CERN Document Server

    Waxman, Eli

    2010-01-01

    In a recent analysis it was found that the local (z=0) rate at which gamma-ray bursts (GRBs) produce energy in 1 MeV photons, Q_GRB(z=0), is 300 times lower than the local energy production rate in ultra-high energy cosmic-rays. This may appear to be in contradiction with earlier results, according to which Q_GRB(z=0) is similar to the local energy production rate in >10^{19} eV cosmic-rays, Q_{10EeV}(z=0). This short (1 page) note identifies the origin of the apparent discrepancy and shows that Q_GRB(z=0) Q_{10EeV}(z=0) holds.

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

    Science.gov (United States)

    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.

  18. Maximising electricity production by controlling the biofilm specific growth rate in microbial fuel cells.

    Science.gov (United States)

    Ledezma, Pablo; Greenman, John; Ieropoulos, Ioannis

    2012-08-01

    The aim of this work is to study the relationship between growth rate and electricity production in perfusion-electrode microbial fuel cells (MFCs), across a wide range of flow rates by co-measurement of electrical output and changes in population numbers by viable counts and optical density. The experiments hereby presented demonstrate, for the first time to the authors' knowledge, that the anodic biofilm specific growth rate can be determined and controlled in common with other loose matrix perfusion systems. Feeding with nutrient-limiting conditions at a critical flow rate (50.8 mL h(-1)) resulted in the first experimental determination of maximum specific growth rate μ(max) (19.8 day(-1)) for Shewanella spp. MFC biofilms, which is considerably higher than those predicted or assumed via mathematical modelling. It is also shown that, under carbon-energy limiting conditions there is a strong direct relationship between growth rate and electrical power output, with μ(max) coinciding with maximum electrical power production.

  19. Volumetric flow rate comparisons for water and product on pasteurization systems.

    Science.gov (United States)

    Schlesser, J E; Stroup, W H; McKinstry, J A

    1994-04-01

    A flow calibration tube system was assembled to determine the volumetric flow rates for water and various dairy products through a holding tube, using three different flow promotion methods. With the homogenizer, the volumetric flow rates of water and reconstituted skim milk were within 1.5% of each other. With the positive displacement pump, the flow rate for reconstituted skim milk increased compared with that for water as the pressure increased or temperature decreased. The largest increase in flow rate was at 310-kPa gauge and 20 degrees C. On a magnetic flow meter system, the volumetric flow rates of water and reconstituted skim milk were within .5% of the flow rate measured from the volume collected in a calibrated tank. The flow rate of whole milk was similar to that of skim milk on the three flow promoters evaluated. Ice milk mix increased the flow rate of the positive displacement pump, but not the homogenizer and magnetic flow meter system.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Inventory model with two rates of production for deteriorating items with permissible delay in payments

    Science.gov (United States)

    Roy, Ajanta; Samanta, G. P.

    2011-08-01

    Goyal (1985) ['Economic Order Quantity Under Conditions of Permissible Delay in Payments', Journal of Operational research Society, 36, 35-38] assumed that unit selling price and unit purchasing price are equal. But in real-life the scenario is different. The purpose of this article is to reflect the real life problem by allowing unit selling price and purchasing price to be unequal. Our model is a continuous production control inventory model for deteriorating items in which two different rates of production are available. The results are illustrated with the help of a numerical example. We discuss the sensitivity of the solution together with the changes of the values of the parameters associated with the model. Our model may be applicable in many manufacturing planning situations where management practices for deterioration are stringent; e.g. the two-production rate will be more profitable than the one-production rate in the manufacture of cold, asthma and allergy medicine. Our proposed model might be applicable to develop a prototype advance planning system for those manufacturers to integrate the management science techniques into commercial planning.

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

    Directory of Open Access Journals (Sweden)

    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.

  3. The production rate of cosmogenic 21-Ne in chondrites deduced from 81-Kr measurements

    Science.gov (United States)

    Schultz, L.; Freundel, M.

    1986-01-01

    Cosmogenic Ne-21 is used widely to calculate exposure ages of stone meteorites. In order to do so, the production rate P(21) must be known. This rate, however, is dependent on the chemical composition of the meteorite as well as the mass of, and position within, the meteoroid during its exposure to the cosmic radiation. Even for a mean shielding the production rates determined from measurments of different radionuclides vary by a factor of two. A method that can be used to determine exposure ages of meteorites that avoids shielding and chemical composition corrections is the -81-Kr-Kr-method. However, for chondrites, in many cases, the direct determination of production rates for the Kr isotopes is prevented by the trapped gases and the neutron effects on bromine. Therefore, this method was applied to four eucrite falls and then their 81-Kr-83-Kr-ages were compared to their cosmogenic Ne-21 and Ar-38 concentrations. The eucrites Bouvante-le-Haut, Juvinas, Sioux County, and Stannern were chosen for these measurements because of their similar chemical composition regarding the major elements.

  4. The trend of production rates with heliocentric distance for comet P/Halley

    Science.gov (United States)

    Fink, Uwe

    1994-01-01

    Comet P/Halley was observed spectroscopically in the wavelength range 5200-10,400 A during 10 observing runs, roughly a month apart from 1985 August 28 to 1986 June 6. The observations span a heliocentric distance from 0.73 to 2.52 AU. This data set is analyzed to determine the course of the production rate with heliocentric distance for C2, NH2, CN, and the continuum. The effect of changing the Haser scale lengths and their heliocentric distance dependence is examined. The production rate ratios to water change only in a minor way, but the absolute values of the production rates are more severely affected. Fluorescent efficiencies, or g-factors for the CN red system are calculated, and band intensity ratios for NH2 and CN are presented. Using presently available fluorescence efficiencies and Haser scale lengths, mixing ratios for the parents of C2, CN, and NH2 with respect to water are: 0.34 +/- 0.07%, 0.15 +/- 0.04%, and 0.13 +/- 0.05%. It is found that these mixing ratios are essentially constant over the heliocentric distance range of the observations, implying a rather uniform nucleus and uniform outgassing characteristics, although there are indications of smaller scale day-to-day variations. The results provide strong observational confirmation that water evaporation controls the activity of the comet over the distance range studied. Continuum values Af rho are determined, and their ratios to QH2O are found to have a clear dependence with heliocentric distance approximately r(exp -1.0) with a post-perihelion enhancement. No correlation of the production rate ratios with light curve of P/Halley were found, nor was there any correlation of the C2 or CN production with the dust.

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

    Science.gov (United States)

    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

  6. Exceptionally High Rates of Biological Hydrogen Production by Biomimetic In Vitro Synthetic Enzymatic Pathways.

    Science.gov (United States)

    Kim, Eui-Jin; Wu, Chang-Hao; Adams, Michael W W; Zhang, Y-H Percival

    2016-11-02

    Hydrogen production by water splitting energized by biomass sugars is one of the most promising technologies for distributed green H2 production. Direct H2 generation from NADPH, catalysed by an NADPH-dependent, soluble [NiFe]-hydrogenase (SH1) is thermodynamically unfavourable, resulting in slow volumetric productivity. We designed the biomimetic electron transport chain from NADPH to H2 by the introduction of an oxygen-insensitive electron mediator benzyl viologen (BV) and an enzyme (NADPH rubredoxin oxidoreductase, NROR), catalysing electron transport between NADPH and BV. The H2 generation rates using this biomimetic chain increased by approximately five-fold compared to those catalysed only by SH1. The peak volumetric H2 productivity via the in vitro enzymatic pathway comprised of hyperthermophilic glucose 6-phosphate dehydrogenase, 6-phosphogluconolactonase, and 6-phosphogluconate dehydrogenase, NROR, and SH1 was 310 mmol H2 /L h(-1) , the highest rate yet reported. The concept of biomimetic electron transport chains could be applied to both in vitro and in vivo H2 production biosystems and artificial photosynthesis.

  7. Sea-ice algal primary production and nitrogen uptake rates off East Antarctica

    Science.gov (United States)

    Roukaerts, Arnout; Cavagna, Anne-Julie; Fripiat, François; Lannuzel, Delphine; Meiners, Klaus M.; Dehairs, Frank

    2016-09-01

    Antarctic pack ice comprises about 90% of the sea ice in the southern hemisphere and plays an important structuring role in Antarctic marine ecosystems, yet measurements of ice algal primary production and nitrogen uptake rates remain scarce. During the early austral spring of 2012, measurements for primary production rates and uptake of two nitrogen substrates (nitrate and ammonium) were conducted at 5 stations in the East Antarctic pack ice (63-66°S, 115-125°E). Carbon uptake was low (3.52 mg C m-2 d-1) but a trend of increased production was observed towards the end of the voyage suggesting pre-bloom conditions. Significant snow covers reaching, up to 0.8 m, induced strong light limitation. Two different regimes were observed in the ice with primarily nitrate based 'new' production (f-ratio: 0.80-0.95) at the bottom of the ice cover, due to nutrient-replete conditions at the ice-water interface, and common for pre-bloom conditions. In the sea-ice interior, POC:PN ratios (20-70) and higher POC:Chl a ratios suggested the presence of large amounts of detrital material trapped in the ice and here ammonium was the prevailing nitrogen substrate. This suggests that most primary production in the sea-ice interior was regenerated and supported by a microbial food web, recycling detritus.

  8. Urine production rate and water balance in the terrestrial crabs Gecarcinus lateralis and Cardisoma guanhumi.

    Science.gov (United States)

    Harris, R R

    1977-06-01

    1. The rate of urine production in the terrestrial crabs Gecarcinus lateralis (Freminville) and Cardisoma guanhumi Latreille maintained on s.w.-moist sand was measured by inulin clearance. 2. The inulin U/B ratios in both species rose to about unity after 48 h, and remained at this level. It was concluded that neither species withdrew water from the primary urine. 3. The relatively high rate of inulin clearance in G. lateralis (10-69% body wt day-1) was considerably reduced when animals were transferred to dry sand (2-15% body wt day-1). 4. The rate of water loss on dry sand was measured in G. lateralis and changes in the haemolymph and urine osmolality recorded. 5. The prevention of possible reabsorption of water from voided urine did not appear to affect significantly the rate of water loss in conditions of water deprivation. 6. The maintenance of urine production rates measured on s.w.-moist sand would double the water loss of G. lateralis in dry conditions.

  9. Corrosion rate estimations of microscale zerovalent iron particles via direct hydrogen production measurements.

    Science.gov (United States)

    Velimirovic, Milica; Carniato, Luca; Simons, Queenie; Schoups, Gerrit; Seuntjens, Piet; Bastiaens, Leen

    2014-04-15

    In this study, the aging behavior of microscale zerovalent iron (mZVI) particles was investigated by quantifying the hydrogen gas generated by anaerobic mZVI corrosion in batch degradation experiments. Granular iron and nanoscale zerovalent iron (nZVI) particles were included in this study as controls. Firstly, experiments in liquid medium (without aquifer material) were performed and revealed that mZVI particles have approximately a 10-30 times lower corrosion rate than nZVI particles. A good correlation was found between surface area normalized corrosion rate (RSA) and reaction rate constants (kSA) of PCE, TCE, cDCE and 1,1,1-TCA. Generally, particles with higher degradation rates also have faster corrosion rates, but exceptions do exists. In a second phase, the hydrogen evolution was also monitored during batch tests in the presence of aquifer material and real groundwater. A 4-9 times higher corrosion rate of mZVI particles was observed under the natural environment in comparison with the aquifer free artificial condition, which can be attributed to the low pH of the aquifer and its buffer capacity. A corrosion model was calibrated on the batch experiments to take into account the inhibitory effects of the corrosion products (dissolved iron, hydrogen and OH(-)) on the iron corrosion rate.

  10. A Scalable Method for Extracting Soiling Rates from PV Production Data

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-11-21

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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%.

  13. Stellar production rates of carbon and its abundance in the universe

    CERN Document Server

    Oberhummer, Heinz; Schlattl, H; 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 Coulomb forces, respectively, the stellar production of carbon or oxygen is reduced by factors of 30 to 1000.

  14. Effect of stocking rate on pasture production, milk production, and reproduction of dairy cows in pasture-based systems.

    Science.gov (United States)

    Macdonald, K A; Penno, J W; Lancaster, J A S; Roche, J R

    2008-05-01

    Ninety-four cows were randomly allocated to 1 of 5 stocking rates (2.2, 2.7, 3.1, 3.7, and 4.3 cows/ha) in a completely randomized design for 3 years. Herds were seasonal calving, with only minor differences in grazing management to optimize the profitability of each stocking rate (SR). Pasture production and quality data, milk and milk component data, and reproduction data were collected, averaged for SR treatment, and linear and quadratic contrasts on SR were evaluated. In addition, the Wilmink exponential model (y(t) = a + b x e((-0.05t) )+ c x t) was fitted to milk yield within lactation, and the parameters were averaged by SR treatment and analyzed as above. The median variation explained by the function for individual lactations was 84%. The amount of pasture grown tended to increase, and the quality of the pasture on offer increased linearly with increasing SR, reducing some of the negative impact of SR on the availability of pasture per cow. Milk production per cow declined linearly with increasing SR, although there was a tendency for most production variables to decline quadratically, with the negative effect of SR declining with increasing SR. The effect on milk production per cow was primarily because of a lower peak milk yield and a greater post-peak decline (less persistent milk profile), although a decline in lactation length with increasing SR was responsible for 24% of the effect of SR on milk yield. Milk production per hectare increased linearly with increasing SR, and there was only a small difference (approximately 3%/cow per ha) in the efficiency of converting feed dry matter into milk energy. Stocking rate did not affect reproductive success. The data are consistent with the need for a more robust measure of SR than cows per hectare because farms will differ in the genetic merit of their cows and in the potential to produce pasture. We introduce the concept of a comparative SR, whereby the carrying capacity of the farm is defined by the BW of

  15. Subterranean production of neutrons, 39Ar and 21Ne: Rates and uncertainties

    Science.gov (United States)

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

    2017-01-01

    Accurate understanding of the subsurface production rate of the radionuclide 39Ar 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, 21Ne , and 39Ar take advantage of the state-of-the-art reliable 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, 21Ne , and 39Ar 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 107-1010 α particles are produced in one kilogram of rock per year (order of 1-103 kg-1 s-1); the number of produced neutrons is lower by ∼ 6 orders of magnitude, 21Ne production rate drops by an additional factor of 15-20, and another one order of magnitude or more is dropped in production of 39Ar. Our calculation yields a nucleogenic 21Ne /4He production ratio of (4.6 ± 0.6) ×10-8 in Continental Crust and (4.2 ± 0.5) ×10-8 in Oceanic Crust and Depleted Mantle. Calculated 39Ar production rates span a great range from 29 ± 9 atoms kg-rock-1 yr-1 in the K-Th-U-enriched Upper Continental Crust to (2.6 ± 0.8) × 10-4 atoms kg-rock-1 yr-1 in Depleted Upper Mantle. Nucleogenic 39Ar production exceeds the cosmogenic production below ∼700 m depth and thus, affects radiometric ages of groundwater. The 39Ar chronometer, which fills in a gap between 3H and 14C , is particularly important given the need to tap deep reservoirs of ancient drinking water.

  16. Increasing Biogas Production Rate from Cattle Manure Using Rumen Fluid as Inoculums

    Directory of Open Access Journals (Sweden)

    Budiyono Budiyono

    2013-10-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 In this study, rumen fluid of animal ruminant was used as inoculums to increase biogas production rate from cattle manure at mesophilic condition. A series of laboratory experiments using 400 ml biodigester were performed in batch operation mode. Given 100 grams of fresh cattle manure (M was fed to each biodigester and mixed with rumen fluid (R and tap water (W in several ratio resulting six different M:W:R ratio contents i.e. 1:1:0; 1:0.75:0.25; 1:0.5:0.5; 1:0.25:0.75; and 1:0:1 (correspond to 0; 12.5; 25, 37.5; 50, and 100 % rumen, respectively and six different total solid (TS contents i.e. 2.6, 4.6, 6.2, 7.4, 9.2, 12.3, and 18.4 %. The operating temperatures were at room temperature. The results showed that the rumen fluid inoculated to biodigester significantly effected the biogas production. Rumen fluid inoculums caused biogas production rate and efficiency increase more than two times in compare to manure substrate without rumen fluid inoculums. The best performance for biogas production was the digester with rumen fluid and TS content in the range of 25-50 % and 7.4 and 9.2 %, respectively. These results suggest that, based on TS content effects to biogas yield, rumen fluid inoculums exhibit the similar effect with other inoculums. Increasing rumen content will also increase biogas production. Due to the optimum total solid (TS content for biogas production between 7-9 % (or correspond to more and less manure and total liquid 1:1, the rumen fluid content of 50 % will give the best performance for biogas production. The future work will be carried out to study the dynamics of biogas production if both the rumen fluid inoculums and manure are fed in the continuous system Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Doi: 10.12777/ijse.6.1.31-38 [How to cite this article: Budiyono, Widiasa, I.N., Johari, S. and Sunarso. (2014. Increasing Biogas

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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. Meta-analysis of the impact of stocking rate on the productivity of pasture-based milk production systems.

    Science.gov (United States)

    McCarthy, B; Delaby, L; Pierce, K M; Journot, F; Horan, B

    2011-04-01

    The objective of this study is to quantify the milk production response per cow and per hectare (ha) for an incremental stocking rate (SR) change, based on a meta-analysis of published research papers. Suitable experiments for inclusion in the database required a comparison of at least two SRs under the same experimental conditions in addition to details on experimental length and milk production results per cow and per ha. Each additional increased SR treatment was also described in terms of the relative milk production change per cow and per ha compared to the lower base SR (b_SR). A database containing 109 experiments of various lengths with 131 comparisons of SR was sub-divided into Type I experiments (common experimental lengths) and Type II experiments (variable experimental lengths). Actual and proportional changes in milk production according to SR change were analysed using linear mixed model procedures with study included as a random effect in the model. Low residual standard errors indicated a good precision of the predictive equations with the exception of proportional change in milk production per cow. For all milk yield variables analysed, the results illustrate that while production per cow is reduced, a strong positive relationship exists between SR and milk production per ha. An SR increase of one cow/ha resulted in a decrease in daily milk yield per cow of 7.4% and 8.7% for Type I and Type II data, respectively, whereas milk yield per ha increased by 20.1% and 19.6%, respectively. Within the Type II data set, a one cow/ha increase in SR also resulted in a 15.1% reduction in lactation length (equivalent to 42 days). The low predictability of proportional change in milk production per cow according to the classical SR definition of cows per ha over a defined period suggests that SR may be more appropriately defined in terms of the change in available feed offered per animal within each treatment.

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

    Science.gov (United States)

    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

  1. Investigating why recycling gravity harvested algae increases harvestability and productivity in high rate algal ponds.

    Science.gov (United States)

    Park, J B K; Craggs, R J; Shilton, A N

    2013-09-15

    It has previously been shown that recycling gravity harvested algae promotes Pediastrum boryanum dominance and improves harvestability and biomass production in pilot-scale High Rate Algal Ponds (HRAPs) treating domestic wastewater. In order to confirm the reproducibility of these findings and investigate the mechanisms responsible, this study utilized twelve 20 L outdoor HRAP mesocosms operated with and without algal recycling. It then compared the recycling of separated solid and liquid components of the harvested biomass against un-separated biomass. The work confirmed that algal recycling promoted P. boryanum dominance, improved 1 h-settleability by >20% and increased biomass productivity by >25% compared with controls that had no recycling. With regard to the improved harvestability, of particular interest was that recycling the liquid fraction alone caused a similar improvement in settleability as recycling the solid fraction. This may be due to the presence of extracellular polymeric substances in the liquid fraction. While there are many possible mechanisms that could account for the increased productivity with algal recycling, all but two were systematically eliminated: (i) the mean cell residence time was extended thereby increasing the algal concentration and more fully utilizing the incident sunlight and, (ii) the relative proportions of algal growth stages (which have different specific growth rates) was changed, resulting in a net increase in the overall growth rate of the culture.

  2. Effects of allometry, productivity and lifestyle on rates and limits of body size evolution

    Science.gov (United States)

    Okie, Jordan G.; Boyer, Alison G.; Brown, James H.; Costa, Daniel P.; Ernest, S. K. Morgan; Evans, Alistair R.; Fortelius, Mikael; Gittleman, John L.; Hamilton, Marcus J.; Harding, Larisa E.; Lintulaakso, Kari; Lyons, S. Kathleen; Saarinen, Juha J.; Smith, Felisa A.; Stephens, Patrick R.; Theodor, Jessica; Uhen, Mark D.; Sibly, Richard M.

    2013-01-01

    Body size affects nearly all aspects of organismal biology, so it is important to understand the constraints and dynamics of body size evolution. Despite empirical work on the macroevolution and macroecology of minimum and maximum size, there is little general quantitative theory on rates and limits of body size evolution. We present a general theory that integrates individual productivity, the lifestyle component of the slow–fast life-history continuum, and the allometric scaling of generation time to predict a clade's evolutionary rate and asymptotic maximum body size, and the shape of macroevolutionary trajectories during diversifying phases of size evolution. We evaluate this theory using data on the evolution of clade maximum body sizes in mammals during the Cenozoic. As predicted, clade evolutionary rates and asymptotic maximum sizes are larger in more productive clades (e.g. baleen whales), which represent the fast end of the slow–fast lifestyle continuum, and smaller in less productive clades (e.g. primates). The allometric scaling exponent for generation time fundamentally alters the shape of evolutionary trajectories, so allometric effects should be accounted for in models of phenotypic evolution and interpretations of macroevolutionary body size patterns. This work highlights the intimate interplay between the macroecological and macroevolutionary dynamics underlying the generation and maintenance of morphological diversity. PMID:23760865

  3. Dispensing rates of four common hearing aid product features: associations with variations in practice among audiologists.

    Science.gov (United States)

    Johnson, Earl E; Ricketts, Todd A

    2010-03-01

    The purpose of the study was to develop and examine a list of potential variables that may account for variability in the dispensing rates of four common hearing aid features. A total of 29 potential variables were identified and placed into the following categories: (1) characteristics of the audiologist, (2) characteristics of the hearing aids dispensed by the audiologist, (3) characteristics of the audiologist's patient population, and (4) evidence-based practice grades of recommendation for each feature. The potentially associative variables then were examined using regression analyses from the responses of 257 audiologists to a dispensing practice survey. There was a direct relation between price and level of hearing aid technology with the frequency of dispensing product features. There was also a direct relation between the belief by the audiologist that a feature might benefit patients and the frequency of dispensing that feature. In general, the results suggested that personal differences among audiologists and the hearing aids audiologists choose to dispense are related more strongly to dispensing rates of product features than to differences in characteristics of the patient population served by audiologists. An additional finding indicated that evidence-based practice recommendations were inversely related to dispensing rates of product features. This finding, however, may not be the result of dispensing trends as much as hearing aid manufacturing trends.

  4. Herschel/SPIRE observations of water production rates and ortho-to-para ratios in comets★

    Science.gov (United States)

    Wilson, Thomas G.; Rawlings, Jonathan M. C.; Swinyard, Bruce M.

    2017-04-01

    This paper presents Herschel/SPIRE (Spectral and Photometric Imaging Receiver) spectroscopic observations of several fundamental rotational ortho- and para-water transitions seen in three Jupiter-family comets and one Oort-cloud comet. Radiative transfer models that include excitation by collisions with neutrals and electrons, and by solar infrared radiation, were used to produce synthetic emission line profiles originating in the cometary coma. Ortho-to-para ratios (OPRs) were determined and used to derived water production rates for all comets. Comparisons are made with the water production rates derived using an OPR of 3. The OPR of three of the comets in this study is much lower than the statistical equilibrium value of 3; however they agree with observations of comets 1P/Halley and C/2001 A2 (LINEAR), and the protoplanetary disc TW Hydrae. These results provide evidence suggesting that OPR variation is caused by post-sublimation gas-phase nuclear-spin conversion processes. The water production rates of all comets agree with previous work and, in general, decrease with increasing nucleocentric offset. This could be due to a temperature profile, additional water source or OPR variation in the comae, or model inaccuracies.

  5. Ultra- cold neutron sources: UCN production rate in solid deuterium converter

    Directory of Open Access Journals (Sweden)

    R Gheisari

    2016-06-01

    Full Text Available A new model is presented herein to calculate optimal value for ultra-cold neutron (UCN production rate of a UCN source. The cold neutron (CN converter is the main component of UCN source. In this paper, we study the UCN source which contains the D2O neutron moderator, the sD2 converter, 590 Mev proton beam, and the spallation target (a mixture of Pb, D2O and Zr. In order to determine the quantities, the neutron transport equation, written in MATLAB, has been combined with the MCNPX simulation code. The neutron transport equation in cylindrical coordinate has been solved everywhere in sD2 by using simulated CN flux as boundary value. By loading a cylindrical shell with different materials, surrounding the converter, different values for UCN production rate and density were obtained. The results of the UCN production rate and density and their comparison with previous results show that the present method has a good capability for optimization of UCN source parameters.

  6. Effects of allometry, productivity and lifestyle on rates and limits of body size evolution.

    Science.gov (United States)

    Okie, Jordan G; Boyer, Alison G; Brown, James H; Costa, Daniel P; Ernest, S K Morgan; Evans, Alistair R; Fortelius, Mikael; Gittleman, John L; Hamilton, Marcus J; Harding, Larisa E; Lintulaakso, Kari; Lyons, S Kathleen; Saarinen, Juha J; Smith, Felisa A; Stephens, Patrick R; Theodor, Jessica; Uhen, Mark D; Sibly, Richard M

    2013-08-01

    Body size affects nearly all aspects of organismal biology, so it is important to understand the constraints and dynamics of body size evolution. Despite empirical work on the macroevolution and macroecology of minimum and maximum size, there is little general quantitative theory on rates and limits of body size evolution. We present a general theory that integrates individual productivity, the lifestyle component of the slow-fast life-history continuum, and the allometric scaling of generation time to predict a clade's evolutionary rate and asymptotic maximum body size, and the shape of macroevolutionary trajectories during diversifying phases of size evolution. We evaluate this theory using data on the evolution of clade maximum body sizes in mammals during the Cenozoic. As predicted, clade evolutionary rates and asymptotic maximum sizes are larger in more productive clades (e.g. baleen whales), which represent the fast end of the slow-fast lifestyle continuum, and smaller in less productive clades (e.g. primates). The allometric scaling exponent for generation time fundamentally alters the shape of evolutionary trajectories, so allometric effects should be accounted for in models of phenotypic evolution and interpretations of macroevolutionary body size patterns. This work highlights the intimate interplay between the macroecological and macroevolutionary dynamics underlying the generation and maintenance of morphological diversity.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Investigation the Impact of Exchange Rate Volatility on the Export of Agricultural Products

    Directory of Open Access Journals (Sweden)

    M. Jamalipour

    2016-10-01

    coefficients. Results and Discussion: Main results showed that real exchange rate volatility and export value of selected commodities are Co-integrated. The coefficient estimation of FMOLS and DOLS methods are equal and statically significant; so, these methods aren’t statically different and they showed that real exchange rate volatility has a negative impact on exported value for whole panel. However, the specific coefficient for each commodity showed contradictory behavior in short run and long run; for example real exchange rate fluctuation has a negative and significant impact on all the commodities; but, in short run this variable has a positive and significant impact on exported value. Moreover, based on estimated results it seems that fluctuation in exchange market has a greater impact on more valuable commodities like date. Conclusion: Considering the importance of agricultural product trade and in order to overcome mono-product economy, this study investigated long term and short term relation between export of grape, orange, date and exchange rate volatilities. To this aim, first the index of exchange volatility using generated autoregressive conditional heteroscedasticity (GARCH was calculated. In order to investigate the relation between exchange rate volatilities and export value of agricultural product, unit root test and cointegration test related to panel data were used during years 1971-2013. The results of model estimation showed that exchange rate volatilities in short term and long term have respectively positive and negative effects on the export value of orange, grape and date. In long term, the negative effects of Exchange rate volatilities on high-export-value products are more than its effects on low-export-value products. Based on the estimation results we can conclude that, in short run, exporters are willing to increase their interchange and gain profits of the volatility in exchange market; however, in long run exchange rate fluctuation has

  9. Does warming affect growth rate and biomass production of shrubs in the High Arctic?

    DEFF Research Database (Denmark)

    Campioli, Matteo; Schmidt, Niels Martin; Albert, Kristian Rost

    2013-01-01

    Few studies have assessed directly the impact of warming on plant growth and biomass production in the High Arctic. Here, we aimed to investigate the impact of 7 years of warming (open greenhouses) on the aboveground relative growth rate (RGR) of Cassiope tetragona and Salix arctica in North......-Eastern Greenland. RGR was assessed for apical (leaves, stem, reproductive organs) and lateral meristems (secondary growth of stem and branches) and accompanied by measures of gross ecosystem production (GEP), branching and tissue carbon (C) concentration. Measurements were based on harvest and biometric methods...... limits the growth of Cassiope but not that of Salix in North-Eastern Greenland. Summer warming thus has the potential to stimulate biomass production in the High Arctic but major species-specific differences are expected....

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

    CERN Document Server

    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...

  11. Influence of light absorption rate by Nannochloropsis oculata on triglyceride production during nitrogen starvation.

    Science.gov (United States)

    Kandilian, Razmig; Pruvost, Jérémy; Legrand, Jack; Pilon, Laurent

    2014-07-01

    This study aims to understand the role of light transfer in triglyceride fatty-acid (TG-FA) cell content and productivity from microalgae during nitrogen starvation. Large amounts of TG-FA can be produced via nitrogen starvation of microalgae in photobioreactors exposed to intense light. First, spectral absorption and scattering cross-sections of N. oculata were measured at different times during nitrogen starvation. They were used to relate the mean volumetric rate of energy absorption (MVREA) per unit mass of microalgae to the TG-FA productivity and cell content. TG-FA productivity correlated with the MVREA and reached a maximum for MVREA of 13 μmol hν/gs. This indicated that TG-FA synthesis was limited by the photon absorption rate in the PBR. A minimum MVREA of 13 μmol hν/gs was also necessary at the onset of nitrogen starvation to trigger large accumulation of TG-FA in cells. These results will be instrumental in defining protocols for TG-FA production in scaled-up photobioreactors.

  12. Intrinsic autotrophic biomass yield and productivity in algae: modeling spectral and mixing-rate dependence.

    Science.gov (United States)

    Holland, Alexandra D; Wheeler, Dean R

    2011-05-01

    For non-inhibitory irradiances, the rate of algal biomass synthesis was modeled as the product of the algal autotrophic yield Φ(DW) and the flux of photons absorbed by the culture, as described using Beer-Lambert law. As a contrast to earlier attempts, the use of scatter-corrected extinction coefficients enabled the validation of such approach, which bypasses determination of photosynthesis-irradiance (PI) kinetic parameters. The broad misconception that PI curves, or the equivalent use of specific growth rate expressions independent of the biomass concentration, can be extended to adequately model biomass production under light-limitation is addressed. For inhibitory irradiances, a proposed mechanistic model, based on the photosynthetic units (PSU) concept, allows one to estimate a target speed νT across the photic zone in order to limit the flux of photons per cell to levels averting significant reductions in Φ(DW) . These modeled target speeds, on the order of 5-20 m s(-1) for high outdoor irradiances, call for fundamental changes in reactor design to optimize biomass productivity. The presented analysis enables a straightforward bioreactor parameterization, which, in-turn, guides the establishment of conditions ensuring maximum productivity and complete nutrients consumption. Additionally, solar and fluorescent lighting spectra were used to calculate energy to photon-counts conversion factors.

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

    Science.gov (United States)

    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.

  14. Reaction Rates Uncertainties and the Production of F19 in AGB Stars

    CERN Document Server

    Lugaro, M; Karakas, A I; Görres, J; Wiescher, M; Lattanzio, J C; Cannon, R C; Lugaro, Maria; Ugalde, Claudio; Karakas, Amanda I.; Gorres, Joachim; Wiescher, Michael; Lattanzio, John C.; Cannon, Robert C.

    2004-01-01

    We present nucleosynthesis calculations and the resulting 19F stellar yields for a large set of models with different masses and metallicity. We find that the production of fluorine depends on the temperature of the convective pulses, the amount of primary 12C mixed into the envelope by third dredge up and the extent of the partial mixing zone. Then we perform a detailed analysis of the reaction rates involved in the production of 19F and the effects of their uncertainties. We find that the major uncertainties are associated with the 14C(alpha,gamma)18O and the 19F(alpha,p)22Ne reaction rates. For these two reactions we present new estimates of the rates and their uncertainties. The importance of the partial mixing zone is reduced when using our estimate for the 14C(alpha,gamma)18O rate. Taking into account both the uncertainties related to the partial mixing zone and those related to nuclear reactions, the highest values of 19F enhancements observed in AGB stars are not matched by the models. This is a probl...

  15. Scaling of heat production by thermogenic flowers: limits to floral size and maximum rate of respiration.

    Science.gov (United States)

    Seymour, Roger S

    2010-09-01

    Effect of size of inflorescences, flowers and cones on maximum rate of heat production is analysed allometrically in 23 species of thermogenic plants having diverse structures and ranging between 1.8 and 600 g. Total respiration rate (, micromol s(-1)) varies with spadix mass (M, g) according to in 15 species of Araceae. Thermal conductance (C, mW degrees C(-1)) for spadices scales according to C = 18.5M(0.73). Mass does not significantly affect the difference between floral and air temperature. Aroids with exposed appendices with high surface area have high thermal conductance, consistent with the need to vaporize attractive scents. True flowers have significantly lower heat production and thermal conductance, because closed petals retain heat that benefits resident insects. The florets on aroid spadices, either within a floral chamber or spathe, have intermediate thermal conductance, consistent with mixed roles. Mass-specific rates of respiration are variable between species, but reach 900 nmol s(-1) g(-1) in aroid male florets, exceeding rates of all other plants and even most animals. Maximum mass-specific respiration appears to be limited by oxygen delivery through individual cells. Reducing mass-specific respiration may be one selective influence on the evolution of large size of thermogenic flowers.

  16. In Situ Measurement of Local Hydrogen Production Rate by Bubble-Evolved Recording

    Directory of Open Access Journals (Sweden)

    Xiaowei Hu

    2013-01-01

    Full Text Available 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 periods, which were inertia effect dominated period and diffusion effect dominated period, respectively. The tendency of hydrogen bubble growth was similar to that of the gas bubble in boiling, while the difference in bubble diameter and growth time magnitude was great. Meanwhile, we obtained the local hydrogen production rate on photocatalyst active site by measuring hydrogen bubble growth variation characteristics. This method makes it possible to confirm local actual hydrogen evolution rate quantitatively during photocatalytic water splitting.

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

    DEFF Research Database (Denmark)

    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...

  18. Quantification of Viral and Prokaryotic Production Rates in Benthic Ecosystems: A Methods Comparison

    Science.gov (United States)

    Rastelli, Eugenio; Dell’Anno, Antonio; Corinaldesi, Cinzia; Middelboe, Mathias; Noble, Rachel T.; Danovaro, Roberto

    2016-01-01

    Viruses profoundly influence benthic marine ecosystems by infecting and subsequently killing their prokaryotic hosts, thereby impacting the cycling of carbon and nutrients. Previously conducted studies, based on different methodologies, have provided widely differing estimates of the relevance of viruses on benthic prokaryotes. There has been no attempt so far to compare these independent approaches, including contextual comparisons among different approaches for sample manipulation (i.e., dilution or not of the sediments during incubations), between methods based on epifluorescence microscopy (EFM) or radiotracers, and between the use of different radiotracers. Therefore, it has been difficult to identify the most suitable methodologies and protocols to be used as standard approaches for the quantification of viral infections of prokaryotes. Here, we compared for the first time different methods for determining viral and prokaryotic production rates in marine sediments collected at two benthic sites, differing in depth and environmental conditions. We used a highly replicated experimental design, testing the potential biases associated to the incubation of sediments as diluted or undiluted. In parallel, we also compared EFM counts with the 3H-thymidine incubations for the determination of viral production rates, and the use of 3H-thymidine versus 3H-leucine radiotracers for the determination of prokaryotic production. We show here that, independent from sediment dilution, EFM-based values of viral production ranged from 1.4 to 4.6 × 107 viruses g-1 h-1, and were similar but overall less variable compared to those obtained by the 3H-thymidine method (0.3 to 9.0 × 107 viruses g-1h-1). In addition, the prokaryotic production rates were not affected by sediment dilution, and the use of different radiotracers provided very consistent estimates (10.3–35.1 and 9.3–34.6 ngC g-1h-1 using the 3H-thymidine or 3H-leucine method, respectively). These results indicated

  19. Wastewater treatment high rate algal ponds (WWT HRAP) for low-cost biofuel production.

    Science.gov (United States)

    Mehrabadi, Abbas; Craggs, Rupert; Farid, Mohammed M

    2015-05-01

    Growing energy demand and water consumption have increased concerns about energy security and efficient wastewater treatment and reuse. Wastewater treatment high rate algal ponds (WWT HRAPs) are a promising technology that could help solve these challenges concurrently where climate is favorable. WWT HRAPs have great potential for biofuel production as a by-product of WWT, since the costs of algal cultivation and harvest for biofuel production are covered by the wastewater treatment function. Generally, 800-1400 GJ/ha/year energy (average biomass energy content: 20 GJ/ton; HRAP biomass productivity: 40-70 tons/ha/year) can be produced in the form of harvestable biomass from WWT HRAP which can be used to provide community-level energy supply. In this paper the benefits of WWT HRAPs are compared with conventional mass algal culture systems. Moreover, parameters to effectively increase algal energy content and overall energy production from WWT HRAP are discussed including selection of appropriate algal biomass biofuel conversion pathways.

  20. Language-independent talker-specificity in first-language and second-language speech production by bilingual talkers: L1 speaking rate predicts L2 speaking rate.

    Science.gov (United States)

    Bradlow, Ann R; Kim, Midam; Blasingame, Michael

    2017-02-01

    Second-language (L2) speech is consistently slower than first-language (L1) speech, and L1 speaking rate varies within- and across-talkers depending on many individual, situational, linguistic, and sociolinguistic factors. It is asked whether speaking rate is also determined by a language-independent talker-specific trait such that, across a group of bilinguals, L1 speaking rate significantly predicts L2 speaking rate. Two measurements of speaking rate were automatically extracted from recordings of read and spontaneous speech by English monolinguals (n = 27) and bilinguals from ten L1 backgrounds (n = 86): speech rate (syllables/second), and articulation rate (syllables/second excluding silent pauses). Replicating prior work, L2 speaking rates were significantly slower than L1 speaking rates both across-groups (monolinguals' L1 English vs bilinguals' L2 English), and across L1 and L2 within bilinguals. Critically, within the bilingual group, L1 speaking rate significantly predicted L2 speaking rate, suggesting that a significant portion of inter-talker variation in L2 speech is derived from inter-talker variation in L1 speech, and that individual variability in L2 spoken language production may be best understood within the context of individual variability in L1 spoken language production.

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

    Science.gov (United States)

    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.

  2. Composition and production rate of pharmaceutical and chemical waste from Xanthi General Hospital in Greece.

    Science.gov (United States)

    Voudrias, Evangelos; Goudakou, Lambrini; Kermenidou, Marianthi; Softa, Aikaterini

    2012-07-01

    The objective of this work was to determine the composition and production rates of pharmaceutical and chemical waste produced by Xanthi General Hospital in Greece (XGH). This information is important to design and cost management systems for pharmaceutical and chemical waste, for safety and health considerations and for assessing environmental impact. A total of 233 kg pharmaceutical and 110 kg chemical waste was collected, manually separated and weighed over a period of five working weeks. The total production of pharmaceutical waste comprised 3.9% w/w of the total hazardous medical waste produced by the hospital. Total pharmaceutical waste was classified in three categories, vial waste comprising 51.1%, syringe waste with 11.4% and intravenous therapy (IV) waste with 37.5% w/w of the total. Vial pharmaceutical waste only was further classified in six major categories: antibiotics, digestive system drugs, analgesics, hormones, circulatory system drugs and "other". Production data below are presented as average (standard deviation in parenthesis). The unit production rates for total pharmaceutical waste for the hospital were 12.4 (3.90) g/patient/d and 24.6 (7.48) g/bed/d. The respective unit production rates were: (1) for vial waste 6.4 (1.6) g/patient/d and 13 (2.6) g/bed/d, (2) for syringe waste 1.4 (0.4) g/patient/d and 2.8 (0.8) g/bed/d and (3) for IV waste 4.6 (3.0) g/patient/d and 9.2 (5.9) g/bed/d. Total chemical waste was classified in four categories, chemical reagents comprising 18.2%, solvents with 52.3%, dyes and tracers with 18.2% and solid waste with 11.4% w/w of the total. The total production of chemical waste comprised 1.8% w/w of the total hazardous medical waste produced by the hospital. Thus, the sum of pharmaceutical and chemical waste was 5.7% w/w of the total hazardous medical waste produced by the hospital. The unit production rates for total chemical waste for the hospital were 5.8 (2.2) g/patient/d and 1.1 (0.4) g/exam/d. The respective

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Seasonal rates of benthic primary production in a Greenland fjord measured by aquatic eddy correlation

    DEFF Research Database (Denmark)

    Attard, Karl; Glud, Ronnie N.; McGinnis, Daniel F.

    2014-01-01

    . Substantial benthic gross primary production (GPP) was measured year-round. The highest GPP rates were measured during the spring, up to 5.7 mmol O2 m−2 h−1 (136.8 mmol O2 m−2 d−1), and even at low light levels (rates of up to 1.8 mmol O2 m−2...... h−1 (43.2 mmol O2 m−2 d−1) during peak irradiance. The benthic phototrophic communities responded seasonally to ambient light levels and exhibited year-round high photosynthetic efficiency. In situ downwelling irradiances as low as ∼ 2 µmol quanta m−2 s−1 induced an autotrophic response and light...... saturation indices (Ik) were as low as 11 µmol quanta m−2 s−1 in the winter. On an annual timescale, the average areal rate of benthic GPP was 11.5 mol O2 m−2 yr−1, which is ∼ 1.4 times higher than the integrated gross pelagic primary production of the ∼ 30–50 m deep photic zone of the fjord. These results...

  5. The Water Production Rate of Comet 2009 P1 (Garradd) throughout the 2011-2012 Apparition

    Science.gov (United States)

    Combi, Michael R.; Mäkinen, J. T. T.; Bertaux, J.; Quémerais, E.; Ferron, S.

    2012-10-01

    The all-sky hydrogen Lyman-alpha camera, SWAN (Solar Wind Anisotropies), on the SOlar and Heliospheric Observatory (SOHO) satellite made observations of the hydrogen coma of comet 2009 P1 (Garradd) throughout its apparition from August 15, 2011 through April 6, 2012. SOHO has been operating in a halo orbit around the Earth-Sun L1 Lagrange point since its launch in late 1995. Most water vapor produced by the comet is ultimately photodissociated into two H atoms and one O atom producing a huge atomic hydrogen coma that is routinely observed in the daily full-sky SWAN images in comets of sufficient brightness. Water production rates were calculated from 117 images over 8 months of the apparition using our time-resolved model (Mäkinen & Combi, 2005, Icarus 177, 217), yielding about 1 observation every 2 days on the average. The activity during much of the pre-perihelion leg was dominated by likely seasonal variability rather than a consistent increasing trend with decreasing heliocentric distance and varied between 1 and 3 x 1029 s-1. A single peak value for the water production rate (4 x 1029 s-1) was found on November 3, 2011, 50 days before perihelion. On the other hand during the post-perihelion leg the production rate decreased rather consistently from 2 x 1029 s-1at perihelion, approximately as r-4.6, where r is the heliocentric distance. The overall shape of the variation with time over the apparition shows many of the same general features as the visual light curve of Yoshida (http://www.aerith.net/comet/catalog/index-T-earth.html). SOHO is an international cooperative mission between ESA and NASA. Support from grant NNX11AH50G from the NASA Planetary Astronomy Program is also acknowledged.

  6. Phosphine resistance, respiration rate and fitness consequences in stored-product insects.

    Science.gov (United States)

    Pimentel, Marco Aurélio G; Faroni, Lêda Rita D'A; Tótola, Marcos R; Guedes, Raul Narciso C

    2007-09-01

    Resistance to fumigants has been frequently reported in insect pests of stored products and is one of the obstacles in controlling these pests. The authors studied phosphine resistance and its physiological basis in adult insects of 12 populations of Tribolium castaneum (Herbst) (Tenebrionidae), ten populations of Rhyzopertha dominica (F.) (Bostrichidae) and eight populations of Oryzaephilus surinamensis L. (Silvanidae) from Brazil, and the possible existence of fitness costs associated with phosphine resistance in the absence of this fumigant. The bioassays for the detection of phosphine resistance followed the FAO standard method. The production of carbon dioxide and the instantaneous rate of population increase (r(i)) of each population of each species were correlated with their resistance ratios at the LC(50). The resistance ratio at LC(50) in T. castaneum ranged from 1.0- to 186.2-fold, in R. dominica from 2.0- to 71.0-fold and in O. surinamensis from 1.9- to 32.2-fold. Ten populations of T. castaneum, nine populations of R. dominica and seven populations of O. surinamensis were resistant to phosphine. In all three species there was significant association (P phosphine resistance. The populations with lower carbon dioxide production showed a higher resistance ratio, suggesting that the lower respiration rate is the physiological basis of phosphine resistance by reducing the fumigant uptake in the resistant insects. Conversely, populations with higher r(i) showed lower resistance ratios, which could indicate a lower rate of reproduction of the resistant populations compared with susceptible populations. Thus, management strategies based on the interruption of phosphine fumigation may result in reestablishment of susceptibility, and shows good potential for more effective management of phosphine-resistant populations.

  7. Comparison of water production rates from UV spectroscopy and visual magnitudes for some recent comets

    Science.gov (United States)

    Roettger, E. E.; Feldman, P. D.; A'Hearn, M. F.; Festou, M. C.

    1990-01-01

    IUE data on the UV and visible coma emissions of the comets Bradfield, P/Tempel 2, Wilson, and P/Halley, are presently compared with the visual lightcurves from magnitudes reported in the IAU circulars to consider the temporal evolution of these comets. While the water-production rates obtainable from visual magnitudes on the basis of Newburn's (1984) method are consistent with OH-derived rates to first order, they are sometimes either displaced or unable to exhibit the same pre/postperihelion asymmetry. The best agreement is obtained for the relatively dust-free Comet P/Tempel 2. IUE Fine Error Sensor lightcurves are generally in agreement with curves based on total visual magnitude.

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Protease increases fermentation rate and ethanol yield in dry-grind ethanol production.

    Science.gov (United States)

    Johnston, David B; McAloon, Andrew J

    2014-02-01

    The effects of acid protease and urea addition during the fermentation step were evaluated. The fermentations were also tested with and without the addition of urea to determine if protease altered the nitrogen requirements of the yeast. Results show that the addition of the protease had a statistically significant effect on the fermentation rate and yield. Fermentation rates and yields were improved with the addition of the protease over the corresponding controls without protease. Protease addition either with or with added urea resulted in a higher final ethanol yield than without the protease addition. Urea addition levels >1200 ppm of supplemental nitrogen inhibited ethanol production. The economic effects of the protease addition were evaluated by using process engineering and economic models developed at the Eastern Regional Research Center. The decrease in overall processing costs from protease addition was as high as $0.01/L (4 ¢/gal) of denatured ethanol produced.

  10. Rates of processes with coherent production of different particles and the GSI time anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Giunti, Carlo [INFN, Sezione di Torino, Via P. Giuria 1, I-10125 Torino (Italy)], E-mail: giunti@to.infn.it

    2008-07-17

    With the help of an analogy with a double-slit experiment, it is shown that the standard method of calculation of the rate of an interaction process by adding the rates of production of all the allowed channels, regardless of a possible coherence among them, is correct. The claims that the GSI time anomaly is due to the mixing of neutrinos in the final state of the electron-capture process are refuted. It is shown that the GSI time anomaly may be due to quantum beats due to the existence of two coherent energy levels of the decaying ion with an extremely small energy splitting (about 10{sup -15} eV) and relative probabilities having a ratio of about 1/0008.

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

    Institute of Scientific and Technical Information of China (English)

    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.

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

    Directory of Open Access Journals (Sweden)

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

    Science.gov (United States)

    Giovanazzi, Stefano

    2011-01-07

    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.

  14. Biogas production from bioethanol waste: the effect of pH and urea addition to biogas production rate

    Directory of Open Access Journals (Sweden)

    Budiyono Budiyono

    2013-11-01

    Full Text Available Anaerobic treatment is a good choice to treat bioethanol waste due to the high concentration of COD content for producing biogas as renewable energy. The purposes of this study were to study the effect of addition nitrogen source and pH control to biogas production. The laboratory scale-anaerobic digestions used in this experiment were operated in batch system and at room temperature. In determination of optimum pH, bioethanol waste and rumen fluid fed into digesters with initial pH 6.0; 7.0 and 8.0. Influent COD : N ratio (in form of urea used in this study was 700:7 in compare to control.  The results showed that initial pH 7.0 produced the most biogas with total biogas 3.81 mL/g COD. While initial pH 6 and pH 8 had total biogas 3.25 mL/g COD and 3.49 mL/g COD respectively. At urea addition, biogas formed had 52.47% greater than that of at without urea addition (control variable. Controlled pH caused biogas was produced until 90-day investigation and might continue to be produced. Total biogas of control variable (without urea addition and variable with ratio COD:N=700:7 influent were 11.07 mL/g COD and 11.41 mL/g COD respectively.Doi: http://dx.doi.org/10.12777/wastech.1.1.1-5Citation:  Budiyono, Syaichurrozi, I.  and Sumardiono, S. 2013. Biogas production from bioethanol waste: the effect of pH andurea addition to biogas production rate. Waste Technology 1(1:1-5. Doi: http://dx.doi.org/10.12777/wastech.1.1.1-5

  15. Gas-phase ozonolysis of β-ocimene: Temperature dependent rate coefficients and product distribution

    Science.gov (United States)

    Gaona-Colmán, Elizabeth; Blanco, María B.; Barnes, Ian; Teruel, Mariano A.

    2016-12-01

    Rate coefficients for the reaction of β-ocimene with O3 molecules have been determined over the temperature range 288-311 K at 750 Torr total pressure of nitrogen using the relative rate technique. The investigations were performed in a large volume reaction vessel using long-path in-situ Fourier transformed infrared (FTIR) spectroscopy to monitor the reactants and products. A value of k(β-ocimene + O3) = (3.74 ± 0.92) × 10-16 cm3 molecule-1 s-1 has been obtained for the reaction at 298 K. The temperature dependence of the reaction is best described by the Arrhenius expression k = (1.94 ± 0.02) × 10-14 exp [(-1181 ± 51)/T] cm3 molecule-1 s-1. In addition, a product study has been carried out at 298 K in 750 Torr of synthetic air and the following products with yields in molar % were observed: formaldehyde (36 ± 2), acetone (15 ± 1), methylglyoxal (9.5 ± 0.4) and hydroxyacetone (19 ± 1). The formation of formaldehyde can be explained by the addition of O3 to the C1sbnd C2 double bond of the β-ocimene. Addition of O3 to the C6sbnd C7 double bond leads to the formation of acetone and the CH3C·(OO·)CH3 biradical, which can through isomerization/stabilization form methylglyoxal (hydroperoxide channel) and hydroxyacetone. The formed products will contribute to the formation of PAN and derivatives in polluted environments and also the oxidation capacity of the atmosphere.

  16. Assessing Sub-Antarctic Zone primary productivity from fast repetition rate fluorometry

    Science.gov (United States)

    Cheah, Wee; McMinn, Andrew; Griffiths, F. Brian; Westwood, Karen J.; Wright, Simon W.; Molina, Ernesto; Webb, Jason P.; van den Enden, Rick

    2011-11-01

    In situ primary productivity (PP) in the Sub-Antarctic Zone (SAZ) and the Polar Frontal Zone (PFZ) south of Australia was estimated using fast repetition rate fluorometry (FRRF). FRRF-derived PP at Process station 3 (P3) southeast of Tasmania (46°S, 153°E) were higher than P1 in the southwest of Tasmania (46°S, 140°E) and P2 in the Polar Frontal Zone (54°S, 146°E). The FRRF-derived PP rates were well correlated with 14C-uptake rates from one-hour incubations ( r2=0.85, slope=1.23±0.05, pMehler reaction, which are stimulated at high irradiance. Our results indicate that FRRF can be used to estimate photosynthesis rates in the SAZ and PFZ but to derive an accurate estimation of C-fixation requires a detailed understanding of the physiological properties of the cells and their response to oceanographic parameters under different environmental conditions.

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

    CERN Document Server

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, M.; Altwegg, K.; Thomas, N. [Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Fougere, N.; Combi, M. R.; Tenishev, V. M. [Atmospheric, Oceanic and Space Sciences, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109 (United States); Le Roy, L. [Center for Space and Habitability, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland)

    2014-06-20

    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.

  19. Verification of energy dissipation rate scalability in pilot and production scale bioreactors using computational fluid dynamics.

    Science.gov (United States)

    Johnson, Chris; Natarajan, Venkatesh; Antoniou, Chris

    2014-01-01

    Suspension mammalian cell cultures in aerated stirred tank bioreactors are widely used in the production of monoclonal antibodies. Given that production scale cell culture operations are typically performed in very large bioreactors (≥ 10,000 L), bioreactor scale-down and scale-up become crucial in the development of robust cell-culture processes. For successful scale-up and scale-down of cell culture operations, it is important to understand the scale-dependence of the distribution of the energy dissipation rates in a bioreactor. Computational fluid dynamics (CFD) simulations can provide an additional layer of depth to bioreactor scalability analysis. In this communication, we use CFD analyses of five bioreactor configurations to evaluate energy dissipation rates and Kolmogorov length scale distributions at various scales. The results show that hydrodynamic scalability is achievable as long as major design features (# of baffles, impellers) remain consistent across the scales. Finally, in all configurations, the mean Kolmogorov length scale is substantially higher than the average cell size, indicating that catastrophic cell damage due to mechanical agitation is highly unlikely at all scales.

  20. Composition and production rate of medical waste from a small producer in Greece.

    Science.gov (United States)

    Graikos, Anastasios; Voudrias, Evangelos; Papazachariou, Athanasios; Iosifidis, Nikolaos; Kalpakidou, Maria

    2010-01-01

    The objective of this work was to determine the composition and production rate of medical waste from the health care facility of social insurance institute, a small waste producer in Xanthi, Greece. Specifically, produced medical waste from the clinical pathology (medical microbiology) laboratory, the X-ray laboratory and the surgery and injection therapy departments of the health facility was monitored for six working weeks. A total of 240 kg medical solid waste was manually separated and weighed and 330 L of liquid medical waste was measured and classified. The hazardous waste fraction (%w/w) of the medical solid waste was 91.6% for the clinical pathology laboratory, 12.9% for the X-ray laboratory, 24.2% for the surgery departments and 17.6% for the injection therapy department. The infectious waste fraction (%w/w) of the hazardous medical solid waste was 75.6% for the clinical pathology laboratory, 0% for the X-ray laboratory, 100% for the surgery departments and 75.6% for the injection therapy department. The total hazardous medical solid waste production rate was 64+/-15 g/patient/d for the clinical pathology laboratory, 7.2+/-1.6 g/patient/d for the X-ray laboratory, 8.3+/-5.1 g/patient/d for the surgery departments and 24+/-9 g/patient/d for the injection therapy department. Liquid waste was produced by the clinical pathology laboratory (infectious-and-toxic) and the X-ray laboratory (toxic). The production rate for the clinical pathology laboratory was 0.03+/-0.003 L/patient/d and for the X-ray laboratory was 0.06+/-0.006 L/patient/d. Due to the small amount produced, it was suggested that the most suitable management scheme would be to transport the hazardous medical waste, after source-separation, to the Prefectural Hospital of Xanthi to be treated with the hospital waste. Assuming this data is representative of other small medical facilities, medical waste production can be estimated for such facilities distributed around Greece.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Increasing flux rate to shorten leaching period and ramp-up production

    Science.gov (United States)

    Ngantung, Billy; Agustin, Riska; Ravi'i

    2017-01-01

    J Resources Bolaang Mongondow (JBRM) has operated a dynamic heap leach in its Bakan Gold Mine since late 2013. After successfully surpassing its name plate capacity of 2.6 MT/annum in 2014, the clayey and transition ore become the next operational challenge. The presence of transition and clayey ore requires longer leaching period, hence reducing the leach pad capacity which then caused reduced production. Maintaining or even increasing production with such longer leaching ore types can be done by expanding the leach pad area which means an additional capital investment, and/or shortening the leaching cycle which compromise a portion of gold extraction. JBRM has been successfully increasing the leach pad production from 2.6 MT/annum to 3.8 MT/annum, whilst improving the gold extraction from around 70% to around 80%. This was achieved by managing the operation of the leach pad which is shortening the leach cycle by identifying and combining the optimal flux rate application versus the tonne processed in each cell, at no capital investment for expanding the cell capacity.

  3. The effect of organic loading rate and retention time on hydrogen production from a methanogenic CSTR.

    Science.gov (United States)

    Pakarinen, O; Kaparaju, P; Rintala, J

    2011-10-01

    The possibility of shifting a methanogenic process for hydrogen production by changing the process parameters viz., organic loading rate (OLR) and hydraulic retention time (HRT) was evaluated. At first, two parallel semi-continuously fed continuously stirred tank reactors (CSTR) were operated as methanogenic reactors (M1 and M2) for 78 days. Results showed that a methane yield of 198-218 L/kg volatile solids fed (VS(fed)) was obtained when fed with grass silage at an OLR of 2 kgVS/m³/d and HRT of 30 days. After 78 days of operation, hydrogen production was induced in M2 by increasing the OLR from 2 to 10 kgVS/m³/d and shortening the HRT from 30 to 6 days. The highest H₂ yield of 42 L/kgVS(fed) was obtained with a maximum H₂ content of 24%. The present results thus demonstrate that methanogenic process can be shifted towards hydrogen production by increasing the OLR and decreasing HRT.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  5. Scattering Rates For Leptogenesis: Damping of Lepton Flavour Coherence and Production of Singlet Neutrinos

    CERN Document Server

    Garbrecht, Bjorn; Schwaller, Pedro

    2013-01-01

    Using the Closed-Time-Path approach, we perform a systematic leading order calculation of the relaxation rate of flavour correlations of left-handed Standard Model leptons. This quantity is of pivotal relevance for flavoured Leptogenesis in the Early Universe, and we find it to be 5.19*10^-3 T at T=10^7 GeV and 4.83*10^-3 T at T=10^13 GeV. These values apply to the Standard Model with a Higgs-boson mass of 125 GeV. The dependence of the numerical coefficient on the temperature T is due to the renormalisation group running. The leading linear and logarithmic dependencies of the flavour relaxation rate on the gauge and top-quark couplings are extracted, such that the results presented in this work can readily be applied to extensions of the Standard Model. We also derive the production rate of light (compared to the temperature) sterile right-handed neutrinos, a calculation that relies on the same methods. We confirm most details of earlier results, but find a substantially larger contribution from the t-channe...

  6. Effects of irregular cerebrospinal fluid production rate in human brain ventricular system

    Science.gov (United States)

    Hadzri, Edi Azali; Shamsudin, Amir Hamzah; Osman, Kahar; Abdul Kadir, Mohammed Rafiq; Aziz, Azian Abd

    2012-06-01

    Hydrocephalus is an abnormal accumulation of fluid in the ventricles and cavities in the brain. It occurs when the cerebrospinal fluid (CSF) flow or absorption is blocked or when excessive CSF is secreted. The excessive accumulation of CSF results in an abnormal widening of the ventricles. This widening creates potentially harmful pressure on the tissues of the brain. In this study, flow analysis of CSF was conducted on a three-dimensional model of the third ventricle and aqueduct of Sylvius, derived from MRI scans. CSF was modeled as Newtonian Fluid and its flow through the region of interest (ROI) was done using EFD. Lab software. Different steady flow rates through the Foramen of Monro, classified by normal and hydrocephalus cases, were modeled to investigate its effects. The results show that, for normal and hydrocephalus cases, the pressure drop of CSF flow across the third ventricle was observed to be linearly proportionally to the production rate increment. In conclusion, flow rates that cause pressure drop of 5 Pa was found to be the threshold for the initial sign of hydrocephalus.

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

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Ebadian, Ph.D.; S.K. Dua, Ph.D., C.H.P.; Hillol Guha, Ph.D.

    2001-01-01

    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 {micro}m) 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}m, arising from

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

    Directory of Open Access Journals (Sweden)

    O. Oyinbo

    2014-01-01

    Full Text Available 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 this implies that market driven exchange rate policy has been significant in influencing the trend in agricultural share of gross domestic production in Nigeria. However, it is recommended that the monetary authority of Nigeria should closely monitor the movement of the market driven exchange rate so that exchange rate deregulation does not become counterproductive through unhealthy price distortions on agricultural production, international trade and foreign direct investment in the agricultural sector of Nigeria’s economy.

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

    Directory of Open Access Journals (Sweden)

    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

  10. Validation of cosmogenic nuclide production rate scaling factors through direct measurement

    CERN Document Server

    Graham, I J; Ditchburn, R G; Whitehead, N E

    2000-01-01

    sup 7 Be produced in water targets by nuclear interactions of cosmic rays has been measured to determine cosmogenic nuclide production rates as a function of altitude (sea level to 2 km) and geomagnetic latitude (20-79 deg. S). Relative intensities of low energy cosmic ray neutrons have at the same time been measured using neutron monitors based on IGY/NM-64 designed to efficiently thermalise ca. 2-30 MeV neutrons. The research is on-going and we present here preliminary data from the past two years. Water target and neutron flux results are in general agreement, and are consistent with the altitude-dependent scaling factors of Lal [Earth Planet. Sci. Lett. 104 (1991) 4241]. Significant differences between the sea level, latitude-dependent neutron flux data and Lal's predictions are possibly related to the response function of the detector.

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

    CERN Document Server

    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.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  13. Local Entropy Production Rates in a Polymer Electrolyte Membrane Fuel Cell

    Science.gov (United States)

    Siemer, Marc; Marquardt, Tobias; Huerta, Gerardo Valadez; Kabelac, Stephan

    2017-01-01

    A modeling study on a polymer electrolyte membrane fuel cell by means of non-equilibrium thermodynamics is presented. The developed model considers a one-dimensional cell in steady-state operation. The temperature, concentration and electric potential profiles are calculated for every domain of the cell. While the gas diffusion and the catalyst layers are calculated with established classical modeling approaches, the transport processes in the membrane are calculated with the phenomenological equations as dictated by the non-equilibrium thermodynamics. This approach is especially instructive for the membrane as the coupled transport mechanisms are dominant. The needed phenomenological coefficients are approximated on the base of conventional transport coefficients. Knowing the fluxes and their intrinsic corresponding forces, the local entropy production rate is calculated. Accordingly, the different loss mechanisms can be detected and quantified, which is important for cell and stack optimization.

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

    Science.gov (United States)

    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

  15. Magma production rate along the Ninetyeast Ridge and its relationship to Indian plate motion and Kerguelen hot spot activity

    Science.gov (United States)

    Sreejith, K. M.; Krishna, K. S.

    2015-02-01

    The Ninetyeast Ridge, a linear trace of the Kerguelen hot spot in the Indian Ocean, was emplaced on a rapidly drifting Indian plate. Magma production rates along the ridge track are computed using gravity-derived excess crustal thickness data. The production rates change between 2 and 15 m3/s over timescales of 3-16 Myr. Major variations in magma production rates are primarily associated with significant changes in the Indian plate velocity with low-production phases linked to high plate velocity periods. The lowest magma production rate (2 m3/s) at 62 Ma is associated with the rapid northward drift of Indian plate under the influence of the Reunion mantle plume. The contemporaneous slowing of the African plate coincides with increase in magma 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). Short-period variations (~5 Myr) in magma productions may be associated with intrinsic changes in the plume, possibly due to the presence of solitary waves in the plume conduit.

  16. Biodiesel production potential of wastewater treatment high rate algal pond biomass.

    Science.gov (United States)

    Mehrabadi, Abbas; Craggs, Rupert; Farid, Mohammed M

    2016-12-01

    This study investigates the year-round production potential and quality of biodiesel from wastewater treatment high rate algal pond (WWT HRAP) biomass and how it is affected by CO2 addition to the culture. The mean monthly pond biomass and lipid productivities varied between 2.0±0.3 and 11.1±2.5gVSS/m(2)/d, and between 0.5±0.1 and 2.6±1.1g/m(2)/d, respectively. The biomass fatty acid methyl esters were highly complex which led to produce low-quality biodiesel so that it cannot be used directly as a transportation fuel. Overall, 0.9±0.1g/m(2)/d (3.2±0.5ton/ha/year) low-quality biodiesel could be produced from WWT HRAP biomass which could be further increased to 1.1±0.1g/m(2)/d (4.0ton/ha/year) by lowering culture pH to 6-7 during warm summer months. CO2 addition, had little effect on both the biomass lipid content and profile and consequently did not change the quality of biodiesel.

  17. Composition and production rate of dental solid waste and associated management practices in Hamadan, Iran.

    Science.gov (United States)

    Nabizadeh, Ramin; Koolivand, Ali; Jafari, Ahmad Jonidi; Yunesian, Massoud; Omrani, Gasemali

    2012-06-01

    The objective of this study was to identify the components, composition and production rate of dental solid waste and associated management practices in dental offices in Hamadan. A total of 28 offices, including ten general dentist offices, eight specialist dentist offices, five practical dentist offices and five denture maker offices were selected in a random way. Three samples from each selected type were taken and the waste was manually separated into 74 sub-fractions and each sub-fraction was weighed. The results showed that the total annual dental waste production in dental offices was 41947.43 kg. Domestic type, potentially infectious, chemical and pharmaceutical and toxic waste constituted 71.15, 21.40, 7.26 and 0.18%, respectively of this amount. Only seven fractions including gypsum, latex gloves, nylon, dental impression material, used medicine ampoules, saliva-contaminated paper towels and saliva ejectors constituted about 80% of the waste. It was also indicated that there were no effective activity for waste minimization, separation, reuse and recycling in dental offices and the management of sharps, potentially infectious waste and other hazardous waste was poor.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lukic, S.; Gevaert, F.; Kelic, A.; Ricciardi, M.V.; Schmidt, K.H.; Yordanov, O.

    2006-02-15

    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.)

  19. Effect of the organic loading rate on biogas composition in continuous fermentative hydrogen production.

    Science.gov (United States)

    Spagni, Alessandro; Casu, Stefania; Farina, Roberto

    2010-10-01

    Some systems did not select for hydrogen-producing microorganisms and an unexpected growth of hydrogenotrophic methanogens was observed, although the reactors were operated under well-defined operating conditions that could result in biohydrogen production. The aim of this study was to evaluate the effect of the organic loading rate (OLR) on the hydrogen and methane composition of the biogas produced in dark fermentative processes. The study was carried out using an upflow anaerobic sludge blanket (UASB) reactor in order to evaluate the OLR effect in systems with sludge retention. During continuous operation, the UASB reactor showed the slow development of methanogenic activity, related to the applied OLR. The results demonstrate that operating an UASB reactor at pH 5.5 is not enough to prevent the acclimation of methanogens to the acidic pH and therefore long-term biohydrogen production cannot be achieved. Moreover, this study demonstrates that OLR also has an effect on the biogas composition, where the higher the OLR the greater the biogas H2 content.

  20. Calculation of Radioactivity and Dose Rate of Activated Corrosion Products in Water-Cooled Fusion Reactor

    Directory of Open Access Journals (Sweden)

    Jingyu Zhang

    2016-01-01

    Full Text Available In water-cooled reactor, the dominant radioactive source term under normal operation is activated corrosion products (ACPs, which have an important impact on reactor inspection and maintenance. A three-node transport model of ACPs was introduced into the new version of ACPs source term code CATE in this paper, which makes CATE capable of theoretically simulating the variation and the distribution of ACPs in a water-cooled reactor and suitable for more operating conditions. For code testing, MIT PWR coolant chemistry loop was simulated, and the calculation results from CATE are close to the experimental results from MIT, which means CATE is available and credible on ACPs analysis of water-cooled reactor. Then ACPs in the blanket cooling loop of water-cooled fusion reactor ITER under construction were analyzed using CATE and the results showed that the major contributors are the short-life nuclides, especially Mn-56. At last a point kernel integration code ARShield was coupled with CATE, and the dose rate around ITER blanket cooling loop was calculated. Results showed that after shutting down the reactor only for 8 days, the dose rate decreased nearly one order of magnitude, which was caused by the rapid decay of the short-life ACPs.

  1. Effect of intermediate compounds and products on wet oxidation and biodegradation rates of pharmaceutical compounds.

    Science.gov (United States)

    Collado, Sergio; Laca, Adriana; Diaz, Mario

    2013-06-01

    Kinetics of pure compounds in batch agitated reactors are useful data to clarify the characteristics of a given reaction, but they frequently do not provide the required information to design industrial mixed continuous processes because in this case the final and intermediate products interact with the reaction of interest, due to backmixing effects. Simultaneously, the presence and transformations of other compounds, frequent in industrial wastewater treatments, adds more complexity to these types of interactions, whose effect can be different, favorable or unfavorable, for chemical or biological reactions. In this work, batch laboratory reactor data were obtained for the wet oxidation and biodegradation of four phenolic compounds present in a pharmaceutical wastewater and then compared with those collected from industrial continuous stirred tank reactors. For wet oxidation, batch laboratory degradation rates were significantly lower than those found in industrial continuous stirred operation. This behavior was explained by a different distribution of intermediate compounds in lab and industrial treatments, caused by the degree of backmixing and the synergistic effects between phenolic compounds (matrix effects). On the other hand, the specific utilization rates during aerobic biodegradation in the continuous industrial operation were lower than those measured in the laboratory, due to the simultaneous presence of the four pollutants in the industrial process (matrix effects) increasing the inhibitory effects of these compounds and its intermediates.

  2. Group differences in measures of voice production and revised values of maximum airflow declination rate.

    Science.gov (United States)

    Perkell, J S; Hillman, R E; Holmberg, E B

    1994-08-01

    In previous reports, aerodynamic and acoustic measures of voice production were presented for groups of normal male and female speakers [Holmberg et al., J. Acoust. Soc. Am. 84, 511-529 (1988); J. Voice 3, 294-305 (1989)] that were used as norms in studies of voice disorders [Hillman et al., J. Speech Hear. Res. 32, 373-392 (1989); J. Voice 4, 52-63 (1990)]. Several of the measures were extracted from glottal airflow waveforms that were derived by inverse filtering a high-time-resolution oral airflow signal. Recently, the methods have been updated and a new study of additional subjects has been conducted. This report presents previous (1988) and current (1993) group mean values of sound pressure level, fundamental frequency, maximum airflow declination rate, ac flow, peak flow, minimum flow, ac-dc ratio, inferred subglottal air pressure, average flow, and glottal resistance. Statistical tests indicate overall group differences and differences for values of several individual parameters between the 1988 and 1993 studies. Some inter-study differences in parameter values may be due to sampling effects and minor methodological differences; however, a comparative test of 1988 and 1993 inverse filtering algorithms shows that some lower 1988 values of maximum flow declination rate were due at least in part to excessive low-pass filtering in the 1988 algorithm. The observed differences should have had a negligible influence on the conclusions of our studies of voice disorders.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  6. Production rate enhancement of size-tunable silicon nanoparticles by temporally shaping femtosecond laser pulses in ethanol.

    Science.gov (United States)

    Li, Xin; Zhang, Guangming; Jiang, Lan; Shi, Xuesong; Zhang, Kaihu; Rong, Wenlong; Duan, Ji'an; Lu, Yongfeng

    2015-02-23

    This paper proposes an efficient approach for production-rate enhancement and size reduction of silicon nanoparticles produced by femtosecond (fs) double-pulse ablation of silicon in ethanol. Compared with a single pulse, the production rate is ~2.6 times higher and the mean size of the NPs is reduced by ~1/5 with a delay of 2 ps. The abnormal enhancement in the production rate is obtained at pulse delays Δt > 200 fs. The production-rate enhancement is mainly attributed to high photon absorption efficiency. It is caused by an increase in localized transient electron density, which results from the first sub-pulse ionization of ethanol molecules before the second sub-pulse arrives. The phase-change mechanism at a critical point might reduce nanoparticle size.

  7. Magma production rate along the Ninetyeast Ridge and its relationship to Indian plate motion and Kerguelen hot spot activity

    Digital Repository Service at National Institute of Oceanography (India)

    Sreejith, K.M.; Krishna, K.S.

    The Ninetyeast Ridge, a linear trace of the Kerguelen hot spot in the Indian Ocean, was emplaced on a rapidly drifting Indian plate. Magma production rates along the ridge track are computed using gravity-derived excess crustal thickness data...

  8. Determination of proton-induced production cross sections and production rates of {sup 129}I from Te

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Effects of dietary starch content and rate of fermentation on methane production in lactating dairy cows.

    Science.gov (United States)

    Hatew, B; Podesta, S C; Van Laar, H; Pellikaan, W F; Ellis, J L; Dijkstra, J; Bannink, A

    2015-01-01

    The objective of this study was to investigate the effects of starch varying in rate of fermentation and level of inclusion in the diet in exchange for fiber on methane (CH4) production of dairy cows. Forty Holstein-Friesian lactating dairy cows of which 16 were rumen cannulated were grouped in 10 blocks of 4 cows each. Cows received diets consisting of 60% grass silage and 40% concentrate (dry matter basis). Cows within block were randomly assigned to 1 of 4 different diets composed of concentrates that varied in rate of starch fermentation [slowly (S) vs. rapidly (R) rumen fermentable; native vs. gelatinized corn grain] and level of starch (low vs. high; 270 vs. 530g/kg of concentrate dry matter). Results of rumen in situ incubations confirmed that the fractional rate of degradation of starch was higher for R than S starch. Effective rumen degradability of organic matter was higher for high than low starch and also higher for R than S starch. Increased level of starch, but not starch fermentability, decreased dry matter intake and daily CH4 production. Milk yield (mean 24.0±1.02kg/d), milk fat content (mean 5.05±0.16%), and milk protein content (mean 3.64±0.05%) did not differ between diets. Methane expressed per kilogram of fat- and protein-corrected milk, per kilogram of dry matter intake, or as a fraction of gross energy intake did not differ between diets. Methane expressed per kilogram of estimated rumen-fermentable organic matter (eRFOM) was higher for S than R starch-based diets (47.4 vs. 42.6g/kg of eRFOM) and for low than high starch-based diets (46.9 vs. 43.1g/kg of eRFOM). Apparent total-tract digestibility of neutral detergent fiber and crude protein were not affected by diets, but starch digestibility was higher for diets based on R starch (97.2%) compared with S starch (95.5%). Both total volatile fatty acid concentration (109.2 vs. 97.5mM) and propionate proportion (16.5 vs. 15.8mol/100mol) were higher for R starch- compared with S starch

  10. Effect of oxygen transfer rate on cellulases production in stirred tank and internal-loop airlift bioreactors

    OpenAIRE

    Michelin, Michele; Mota,André; Silva,Daniel Pereira da; A.A. Vicente; Teixeira, J. A; Polizeli, Maria de Lourdes T. M.

    2013-01-01

    In an aerobic process, such as enzymes production by fungi, the oxygen supply into fermentation medium is an important factor in order to achieve good productivities. Oxygen has an important role in metabolism and microorganism growth, being of extreme importance the control of both the dissolved oxygen transfer rate into the bioreactor and the oxygen consumption by the microorganism [1,2]. Dissolved oxygen transfer rate can be analyzed and described by means of the mass transfer coefficient,...

  11. Quantifying melt production and degassing rate at mid-ocean ridges from global mantle convection models with plate motion history

    Science.gov (United States)

    Li, Mingming; Black, Benjamin; Zhong, Shijie; Manga, Michael; Rudolph, Maxwell L.; Olson, Peter

    2016-07-01

    The Earth's surface volcanism exerts first-order controls on the composition of the atmosphere and the climate. On Earth, the majority of surface volcanism occurs at mid-ocean ridges. In this study, based on the dependence of melt fraction on temperature, pressure, and composition, we compute melt production and degassing rate at mid-ocean ridges from three-dimensional global mantle convection models with plate motion history as the surface velocity boundary condition. By incorporating melting in global mantle convection models, we connect deep mantle convection to surface volcanism, with deep and shallow mantle processes internally consistent. We compare two methods to compute melt production: a tracer method and an Eulerian method. Our results show that melt production at mid-ocean ridges is mainly controlled by surface plate motion history, and that changes in plate tectonic motion, including plate reorganizations, may lead to significant deviation of melt production from the expected scaling with seafloor production rate. We also find a good correlation between melt production and degassing rate beneath mid-ocean ridges. The calculated global melt production and CO2 degassing rate at mid-ocean ridges varies by as much as a factor of 3 over the past 200 Myr. We show that mid-ocean ridge melt production and degassing rate would be much larger in the Cretaceous, and reached maximum values at ˜150-120 Ma. Our results raise the possibility that warmer climate in the Cretaceous could be due in part to high magmatic productivity and correspondingly high outgassing rates at mid-ocean ridges during that time.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Organic loading rates affect composition of soil-derived bacterial communities during continuous, fermentative biohydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Yonghua; Bruns, Mary Ann [Department of Crop and Soil Sciences, The Pennsylvania State University, University Park, PA 16802 (United States); Zhang, Husen; Salerno, Michael; Logan, Bruce E. [Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802 (United States)

    2008-11-15

    Bacterial community composition during steady-state, fermentative H{sub 2} production was compared across a range of organic loading rates (OLRs) of 0.5-19 g COD l{sup -1} h{sup -1} in a 2-l continuous flow reactor at 30 C. The varied OLRs were achieved with glucose concentrations of 2.5-10 g l{sup -1} and hydraulic retention times of 1-10 h. The synthetic wastewater feed was amended with L-cysteine and maintained at a pH of 5.5. For each run at a given glucose concentration, the reactor was inoculated with an aliquot of well-mixed agricultural topsoil that had been heat-treated to reduce numbers of vegetative cells. At OLRs less than 2 g COD l{sup -1} h{sup -1}, DNA sequences from ribosomal RNA intergenic spacer analysis profiles revealed more diverse and variable populations (Selenomonas, Enterobacter, and Clostridium spp.) than were observed above 2 g COD l{sup -1} h{sup -1} (Clostridium spp. only). An isolate, LYH1, was cultured from a reactor sample (10 g glucose l{sup -1} at a 10-h HRT) on medium containing L-cysteine. In confirming H{sub 2} production by LYH1 in liquid batch culture, lag periods for H{sub 2} production in the presence and absence of L-cysteine were 5 and 50 h, respectively. The 16S rRNA gene sequence of LYH1 indicated that the isolate was a Clostridium sp. affiliated with RNA subcluster Ic, with >99% similarity to Clostridium sp. FRB1. In fluorescent in situ hybridization tests, an oligonucleotide probe complementary to the 16S rRNA of LYH1 hybridized with 90% of cells observed at an OLR of 2 g COD h{sup -1}, compared to 26% of cells at an OLR of 0.5 g COD l{sup -1} h{sup -1}. An OLR of 2 g COD l{sup -1} h{sup -1} appeared to be a critical threshold above which clostridia were better able to outcompete Enterobacteriaceae and other organisms in the mixed soil inoculum. Our results are discussed in light of other biohydrogen studies employing pure cultures and mixed inocula. (author)

  15. Metabolomic and Metagenomic Analysis of Two Crude Oil Production Pipelines Experiencing Differential Rates of Corrosion

    Science.gov (United States)

    Bonifay, Vincent; Wawrik, Boris; Sunner, Jan; Snodgrass, Emily C.; Aydin, Egemen; Duncan, Kathleen E.; Callaghan, Amy V.; Oldham, Athenia; Liengen, Turid; Beech, Iwona

    2017-01-01

    Corrosion processes in two North Sea oil production pipelines were studied by analyzing pig envelope samples via metagenomic and metabolomic techniques. Both production systems have similar physico-chemical properties and injection waters are treated with nitrate, but one pipeline experiences severe corrosion and the other does not. Early and late pigging material was collected to gain insight into the potential causes for differential corrosion rates. Metabolites were extracted and analyzed via ultra-high performance liquid chromatography/high-resolution mass spectrometry with electrospray ionization (ESI) in both positive and negative ion modes. Metabolites were analyzed by comparison with standards indicative of aerobic and anaerobic hydrocarbon metabolism and by comparison to predicted masses for KEGG metabolites. Microbial community structure was analyzed via 16S rRNA gene qPCR, sequencing of 16S PCR products, and MySeq Illumina shotgun sequencing of community DNA. Metagenomic data were used to reconstruct the full length 16S rRNA genes and genomes of dominant microorganisms. Sequence data were also interrogated via KEGG annotation and for the presence of genes related to terminal electron accepting (TEA) processes as well as aerobic and anaerobic hydrocarbon degradation. Significant and distinct differences were observed when comparing the ‘high corrosion’ (HC) and the ‘low corrosion’ (LC) pipeline systems, especially with respect to the TEA utilization potential. The HC samples were dominated by sulfate-reducing bacteria (SRB) and archaea known for their ability to utilize simple carbon substrates, whereas LC samples were dominated by pseudomonads with the genetic potential for denitrification and aerobic hydrocarbon degradation. The frequency of aerobic hydrocarbon degradation genes was low in the HC system, and anaerobic hydrocarbon degradation genes were not detected in either pipeline. This is in contrast with metabolite analysis, which

  16. High-rate continuous hydrogen production by Thermoanaerobacterium thermosaccharolyticum PSU-2 immobilized on heat-pretreated methanogenic granules

    DEFF Research Database (Denmark)

    O-Thong, Sompong; Prasertsan, P.; Karakashev, Dimitar Borisov;

    2008-01-01

    as carrier to immobilize T. thermosaccharolyticum strain PSU-2 in UASB reactor operated at a hydraulic retention time (HRT) ranging from 0.75 to 24h and corresponding sucrose loading rate from 58.5 to 2.4 mmol sucrose l(-1)h(-1). In comparison with hydrogen production rate of 12.1 mmol H(2)l(-1)h(-1......) obtained by carrier-free reactor upflow anaerobic (UA) system, a greatly improved hydrogen production rate up to 152 mmol H(2)l(-1)h(-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. (C) 2008...

  17. A portable device for estimating the rate of CO2 production in preterm infants.

    Science.gov (United States)

    Kien, C L; Murray, R D; Knerr, T L; McClead, R E; Cordero, L

    1995-01-01

    We developed a simple flow-through system for measuring the net rate of pulmonary excretion of CO2 (VCO2). Its components, connected in series by plastic tubing, are the following: plastic oxygen hood, suction flask used both as a mixing and sampling chamber, Brooks mass flow controller, and wall suction. Gas aliquots withdrawn from the sampling flask are analyzed for CO2 concentration in the laboratory. The system was validated by measuring over a 60-min period the evolution of CO2 from the reaction of sodium carbonate with phosphoric acid. In 9 trials, the mean recovery of CO2 was 99.8%. In 14 studies in 11 preterm infants, we evaluated the reproducibility of duplicate measurements of CO2 production on consecutive days; in 9 of the studies, the coefficient of variation was < 5%, but in other 5 studies, it ranged from 7.7 to 35.8%. We believe that this device might have both research and clinical applicability.

  18. Rate-Product Correlations for the Solvolysis of 5-Nitro-2-Furoyl Chloride

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hojune; Yang, Kiyull; Koo, In Sun [Gyeongsang National Univ., Jinju (Korea, Republic of); Koh, Han Joong [Jeonju National Univ. of Education, Jeonju (Korea, Republic of); Ali, Dildar [Univ. of Balochistan, Quetta (Pakistan)

    2012-10-15

    The solvolysis rate constants of 5-nitro-2-furoyl chloride (5-NO{sub 2}(C{sub 4}H{sub 2}O)-2-COCl, 1) in 27 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N{sub T} solvent nucleophilicity scale and Y{sub Cl} solvent ionizing scale, with sensitivity values of 1.20 ± 0.05 and 0.37 ± 0.02 for l and m, respectively. The activation enthalpies (ΔH{sup ≠}) were 5.63 to 13.0 kcal·mol{sup -1} and the activation entropies (ΔS{sup ≠}) were -25.9 to -43.4 cal·mol{sup -1}·K{sup -1}, which is consistent with the proposed bimolecular reaction mechanism. The solvent kinetic isotope effect (SKIE, k{sub MeOH}/k{sub MeOD}) of 2.65 was also in accord with the S{sub N}2 mechanism and was possibly assisted using a general-base catalysis. The product selectivity (S) for solvolysis of 1 in alcohol/water mixtures was 1.2 to 11, which is also consistent with the proposed bimolecular reaction mechanism.

  19. Production of aerosols by optical catapulting: Imaging, performance parameters and laser-induced plasma sampling rate

    Science.gov (United States)

    Abdelhamid, M.; Fortes, F. J.; Fernández-Bravo, A.; Harith, M. A.; Laserna, J. J.

    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%.

  20. Giotto IMS measurements of the production rate of hydrogen cyanide in the coma of comet Halley

    Energy Technology Data Exchange (ETDEWEB)

    Ip, W.H.; Rosenbauer, H.; Schwenn, R. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau, (DE)); Balsiger, H.; Geiss, J.; Meier, A. (Bern Univ. (CH). Physikalisches Inst.); Goldstein, B.E. (California Inst. of Techn., Pasadena, CA (US)); Lazarus, A.J. (Massachusetts Inst. of Techn., Cambridge, MA (US). Center for Space Research); Shelley, E. (Lockheed Palo Alto Research Lab., CA (US)); Kettmann, G. (Los Alamos National Lab., NM (US))

    1990-05-01

    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) <{approx} 2 x 10{sup -4} Q(H{sub 2}O) at the time of Giotto encounter. The related photo chemical model calculations also indicate that Q(NH{sub 3})/Q(H{sub 2}O) {approx} 5 x 10{sup -3} 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(H{sub 2}O) {approx} 10{sup -3} 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.

  1. Optimum poultry litter rates for maximum profit vs. yield in cotton production

    Science.gov (United States)

    Cotton lint yield responds well to increasing rates of poultry litter fertilization, but little is known of how optimum rates for yield compare with optimum rates for profit. The objectives of this study were to analyze cotton lint yield response to poultry litter application rates, determine and co...

  2. Ion source memory in {sup 36}Cl accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pavetich, Stefan; Akhmadaliev, Shavkat; Merchel, Silke; Rugel, Georg [HZDR, Dresden (Germany); Arnold, Maurice; Aumaitre, Georges; Bourles, Didier; Martschini, Martin [ASTER, Aix-en-Provence (France); Buchriegler, Josef; Golser, Robin; Keddadouche, Karim; Steier, Peter [VERA, Vienna (Austria)

    2013-07-01

    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 {sup 10}Be, {sup 26}Al and {sup 41}Ca. 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 {sup 35}Cl/{sup 37}Cl-ratio and samples containing highly enriched {sup 35}Cl({sup 35}Cl/{sup 37}Cl > 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.

  3. Determination of 36Cl in nuclear waste from reactor decommissioning

    DEFF Research Database (Denmark)

    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...... of this analytical method for Cl-36 is 14 mBq. The method has been used to determine Cl-36 in heavy concrete, aluminum, and graphite from the Danish DR-2 research reactor....

  4. Effects of chemical compositions and ensiling on the biogas productivity and degradation rates of agricultural and food processing by-products.

    Science.gov (United States)

    Kafle, Gopi Krishna; Kim, Sang Hun

    2013-08-01

    The objective of this study was to investigate the effects of chemical compositions and ensiling on the biogas productivity and degradation rates of agricultural and food processing by-products (AFPBPs) using the biogas potential test. The AFPBPs were classified based on their chemical compositions (i.e., carbohydrate, protein and fat contents). The biogas and methane potentials of AFPBPs were calculated to range from 450 to 777 mL/g volatile solids (VS) and 260-543 mL/g VS, respectively. AFPBPs with high fat and protein contents produced significantly higher amounts of biogas than AFPBPs with high carbohydrate and low fat contents. The degradation rate was faster for AFPBPs with high carbohydrate contents compared to AFPBPs with high protein and fat contents. The lag phase and biogas production duration were lower when using ensiled AFPBPs than when using nonsilage AFPBPs. Among the four different silages tested, two silages significantly improved biogas production compared to the nonsilage AFPBPs.

  5. Estimation of the rate of energy production of rat mast cells in vitro

    DEFF Research Database (Denmark)

    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...

  6. Regulating emotions uniquely modifies reaction time, rate of force production, and accuracy of a goal-directed motor action.

    Science.gov (United States)

    Beatty, Garrett F; Fawver, Bradley; Hancock, Gabriella M; Janelle, Christopher M

    2014-02-01

    We investigated how emotion regulation (ER) strategies influence the execution of a memory guided, ballistic pinch grip. Participants (N=33) employed ER strategies (expressive suppression, emotional expression, and attentional deployment) while viewing emotional stimuli (IAPS images). Upon stimulus offset, participants produced a targeted pinch force aimed at 10% of their maximum voluntary contraction. Performance measures included reaction time (RT), rate of force production, and performance accuracy. As hypothesized, attentional deployment resulted in the slowest RT, largest rate of force production, and poorest performance accuracy. In contrast, expressive suppression reduced the rate of force production and increased performance accuracy relative to emotional expression and attentional deployment. Findings provide evidence that emotion regulation strategies uniquely influence human movement. Future work should further delineate the interacting role that emotion regulation strategies have in modulating both affective experience and motor performance.

  7. Estimates of rates and errors for measurements of direct-. gamma. and direct-. gamma. + jet production by polarized protons at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. The Optimal Replenishment Policy under Trade Credit Financing with Ramp Type Demand and Demand Dependent Production Rate

    Directory of Open Access Journals (Sweden)

    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.

  9. Two-stage high-rate biogas (H2 and CH4) production from food waste using anaerobic mixed microflora

    Science.gov (United States)

    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.

  10. 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

    CERN Document Server

    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.

  11. Estimation of Oil Production Rates in Reservoirs Exposed to Focused Vibrational Energy

    KAUST Repository

    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

  12. Production and perception of Persian geminate stops at three speaking rates

    Science.gov (United States)

    Hansen, Benjamin B.

    2004-05-01

    An experiment was designed to determine whether the geminate/singleton category distinction is maintained at fast speaking rates in Persian. Three speakers of Tehrani Persian read test words containing [t,t:,d,d:] in carrier sentences at three speaking rates. The categories do not overlap within a given speaking rate, but the fastest geminates do overlap the normal-rate singletons, implying that the listener must take speaking rate into account in order to perceive the category distinction. The ratio of the consonant closure to the preceding vowel (C/V) is not a useful rate-independent parameter for describing the geminate/singleton boundary in Persian since in Persian the vowel preceding a geminate is slightly longer. However, it was found that the marginal consonant closure (above a minimum closure of about 20 ms) maintains a fixed proportion of the average syllable duration, regardless of rate. This fixed proportion is distinct for geminates and singletons, and so may be used as a single rate-independent parameter for defining the category distinction. Perception tests on natural sentences showed that the distinction is perceptible at each of the three speaking rates. The perceptual response to manipulation of the closure durations indicated that, besides duration, additional cues to the distinction are present.

  13. Charged Higgs boson production in association with a top quark in MC {sup rate} {sup at} NLO

    Energy Technology Data Exchange (ETDEWEB)

    Weydert, C.; Klasen, M. [UJF, CNRS/IN2P3, INPG, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble cedex (France); Frixione, S. [CERN, PH Department, TH unit, Geneva 23 (Switzerland); EPFL, ITPP, Lausanne (Switzerland); Herquet, M. [Nikhef Theory Group, Amsterdam (Netherlands); Laenen, E. [Nikhef Theory Group, Amsterdam (Netherlands); University of Amsterdam, Institute for Theoretical Physics, Amsterdam (Netherlands); Utrecht University, Institute for Theoretical Physics, Utrecht (Netherlands); Plehn, T. [Universitaet Heidelberg, Institut fuer Theoretische Physik, Heidelberg (Germany); Stavenga, G. [Utrecht University, Institute for Theoretical Physics, Utrecht (Netherlands); Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL (United States); White, C.D. [Durham University, Institute for Particle Physics Phenomenology, Department of Physics, Durham, DH1 3LE (United Kingdom)

    2010-06-15

    We discuss the calculation of charged Higgs boson production in association with a top quark in the MC {sup rate} {sup at} NLO framework for combining NLO matrix elements with a parton shower. The process is defined in a model-independent manner for wide applicability, and can be used if the charged Higgs boson mass is either greater or less than the mass of the top quark. For the latter mass region, care is needed in defining the charged Higgs production mode due to interference with top pair production. We give a suitable definition applicable in an NLO (plus parton shower) context, and we present example results for the LHC. (orig.)

  14. Butanol productivity enhancers in wheat straw hydrolyzate: employing potential of enhanced reaction rate

    Science.gov (United States)

    Butanol production by fermentation is gaining momentum due to increased prices of fossil fuels. This biofuel is a major product of acetone-butanol-ethanol (ABE) fermentation that can be produced from hydrolyzed agricultural residues and/or corn. A control glucose (60 g/L) based batch fermentation us...

  15. Integrated rate expression for the production of glucose equivalent in C4 green plant and the effect of temperature

    Indian Academy of Sciences (India)

    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.

  16. Optimizing the compatibility between rating scales and measures of productive second language competence.

    Science.gov (United States)

    Weaver, Christopher

    2011-01-01

    This study presents a systematic investigation concerning the performance of different rating scales used in the English section of a university entrance examination to assess 1,287 Japanese test takers' ability to write a third-person introduction speech. Although the rating scales did not conform to all of the expectations of the Rasch model, they successfully defined a meaningful continuum of English communicative competence. In some cases, the expectations of the Rasch model needed to be weighed against the specific assessment needs of the university entrance examination. This investigation also found that the degree of compatibility between the number of points allotted to the different rating scales and the various requirements of an introduction speech played a considerable role in determining the extent to which the different rating scales conformed to the expectations of the Rasch model. Compatibility thus becomes an important factor to consider for optimal rating scale performance.

  17. Development of a new product for unrestrained heart rate measurement in swimming: a user centered design approach

    NARCIS (Netherlands)

    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

  18. 19 CFR 132.17 - Export certificate for sugar-containing products subject to tariff-rate quota.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Export certificate for sugar-containing products..., DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY QUOTAS Administration of Quotas § 132.17 Export...), the importer must possess a valid export certificate in order to claim the in-quota tariff rate...

  19. A system for accurate on-line measurement of total gas consumption or production rates in microbioreactors

    NARCIS (Netherlands)

    Leeuwen, van Michiel; Heijnen, Joseph J.; Gardeniers, Han; Oudshoorn, Arthur; Noorman, Henk; Visser, Jan; Wielen, van der Luuk A.M.; Gulik, van Walter M.

    2009-01-01

    A system has been developed, based on pressure controlled gas pumping, for accurate measurement of total gas consumption or production rates in the nmol/min range, applicable for on-line monitoring of bioconversions in microbioreactors. The system was validated by carrying out a bioconversion with k

  20. The Influence of New Product Characteristics on Rate of Adoption: Increasing Student Comprehension with the "Bidding for Buyers" Game

    Science.gov (United States)

    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…

  1. Study of Biogas Production Rate from Water Hyacinth by Hydrothermal Pretreatment with Buffalo Dung as a Starter

    Directory of Open Access Journals (Sweden)

    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.

  2. Biologically Induced Hydrogen Production Drives High Rate/High Efficiency Microbial Electrosynthesis of Acetate from Carbon Dioxide

    NARCIS (Netherlands)

    Jourdin, Ludovic; Lu, Yang; Flexer, Victoria; Keller, Jurg; Freguia, Stefano

    2016-01-01

    Electron-transfer pathways occurring in biocathodes are still unknown. We demonstrate here that high rates of acetate production by microbial electrosynthesis are mainly driven by an electron flux from the electrode to carbon dioxide, occurring via biologically induced hydrogen, with (99±1)% elec

  3. Left Ventricular Wall Stress-Mass-Heart Rate Product and Cardiovascular Events in Treated Hypertensive Patients: LIFE Study.

    Science.gov (United States)

    Devereux, Richard B; Bang, Casper N; Roman, Mary J; Palmieri, Vittorio; Boman, Kurt; Gerdts, Eva; Nieminen, Markku S; Papademetriou, Vasilios; Wachtell, Kristian; Hille, Darcy A; Dahlöf, Björn

    2015-11-01

    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 myocardial infarction (MI), possibly related to greater reduction in myocardial oxygen demand by atenolol-based treatment. Myocardial oxygen demand was assessed indirectly by the left ventricular mass×wall stress×heart rate (triple product) in 905 LIFE participants. The triple product was included as time-varying covariate in Cox models assessing predictors of the LIFE primary composite end point (cardiovascular death, MI, or stroke), its individual components, and all-cause mortality. At baseline, the triple product in both treatment groups was, compared with normal adults, elevated in 70% of patients. During 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 more, greater heart rate reduction with atenolol resulted in larger reduction of the triple product. Lower triple product during antihypertensive treatment was strongly, independently associated with lower rates of the LIFE primary composite end point, cardiovascular death, and MI, but not stroke.

  4. Planting Date and Seeding Rate Effects on Sunn Hemp Biomass and Nitrogen Production for a Winter Cover Crop

    Directory of Open Access Journals (Sweden)

    Kipling S. Balkcom

    2011-01-01

    Full Text Available Sunn hemp (Crotalaria juncea L. is a tropical legume that produces plant biomass and nitrogen (N quickly. Our objectives were to assess the growth of a new sunn hemp cultivar breed to produce seed in a temperate climate and determine the residual N effect on a rye (Secale cereale L. cover crop in east-central Alabama from 2007 to 2009. Plant populations, plant height, stem diameter, biomass production, and N content were determined for two sunn hemp planting dates, following corn (Zea mays L. and wheat (Triticum aestivum L. harvest, across different seeding rates (17, 34, 50, and 67 kg/ha. Rye biomass was measured the following spring. Sunn hemp biomass production was inconsistent across planting dates, but did relate to growing degree accumulation. Nitrogen concentrations were inversely related to biomass production, and subsequent N contents corresponded to biomass levels. Neither planting date nor seeding rate affected rye biomass production, but rye biomass averaged over both planting dates following wheat/sunn hemp averaged 43% and 33% greater than rye following fallow. Rye biomass following corn/sunn hemp was equivalent to fallow plots. Early planting dates are recommended for sunn hemp with seeding rates between 17 and 34 kg/ha to maximize biomass and N production.

  5. The Fuzzy Economic Order Quantity Problem with a Finite Production Rate and Backorders

    Directory of Open Access Journals (Sweden)

    Kaj-Mikael Björk

    2012-01-01

    Full Text Available The track of developing Economic Order Quantity (EOQ models with uncertainties described as fuzzy numbers has been very lucrative. In this paper, a fuzzy Economic Production Quantity (EPQ model is developed to address a specific problem in a theoretical setting. Not only is the production time finite, but also backorders are allowed. The uncertainties, in the industrial context, come from the fact that the production availability is uncertain as well as the demand. These uncertainties will be handled with fuzzy numbers and the analytical solution to the optimization problem will be obtained. A theoretical example from the process industry is also given to illustrate the new model.

  6. The Importance of Considering Product Loss Rates in Life Cycle Assessment: The Example of Closure Systems for Bottled Wine

    Directory of Open Access Journals (Sweden)

    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.

  7. Neutron Production Rates by Inverse-Beta Decay in Fully Ionized Plasmas

    CERN Document Server

    Maiani, L; Riquer, V

    2014-01-01

    Recently we showed that the nuclear transmutation rates are largely overestimated in the Widom-Larsen theory of the so called `Low Energy Nuclear Reactions'. Here we show that unbound plasma electrons are even less likely to initiate nuclear transmutations.

  8. Zero valent iron significantly enhances methane production from waste activated sludge by improving biochemical methane potential rather than hydrolysis rate.

    Science.gov (United States)

    Liu, Yiwen; Wang, Qilin; Zhang, Yaobin; Ni, Bing-Jie

    2015-02-05

    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.

  9. Seasonal variation in rates of methane production from peat of various botanical origins: effects of temperature and substrate quality.

    Science.gov (United States)

    Bergman; Klarqvist; Nilsson

    2000-09-01

    The methane produced in peat soils can vary over the growing season due to variations in the supply of available substrate, the activity of the microbial community or changes in temperature. Our aim was to study how these factors regulate the methane production over the season from five different peat types of different botanical origin. Peat samples were collected on seven occasions between June and September. After each sampling, the peat soils were incubated at five different temperatures (7, 10, 15, 20 and 25 degrees C) without added substrate, or at 20 degrees C with added substrate (glucose, or H(2)/CO(2), or starch). Rates of methane production averaged over the season differed significantly (Pmethane production from each plant community varied significantly (Ptemperature, explains the seasonal variation in methane production. However, addition of saturating amounts of glucose, H(2)/CO(2) or starch at 20 degrees C significantly reduced the seasonal variation (Pmethane production in peat from the minerotrophic lawn, wet carpet and mud-bottom plant communities. This suggests that substrate supply (e.g. root exudates) for the micro-organisms also varied over the season at these sites. Seasonal variation in methane production rates was apparent in peat from the hummock and ombrotrophic lawn plant communities even after addition of substrates, suggesting that the active biomass of the anaerobic microbial populations at these sites was regulated by other factors than the ones studied.

  10. Mining consumer reviews to generate ratings of different product attributes while producing feature-based review-summary

    Science.gov (United States)

    Kangale, Akshay; Krishna Kumar, S.; Arshad Naeem, Mohd; Williams, Mark; Tiwari, M. K.

    2016-10-01

    With the massive growth of the internet, product reviews increasingly serve as an important source of information for customers to make choices online. Customers depend on these reviews to understand users' experience, and manufacturers rely on this user-generated content to capture user sentiments about their product. Therefore, it is in the best interest of both customers and manufacturers to have a portal where they can read a complete comprehensive summary of these reviews in minimum time. With this in mind, we arrived at our first objective which is to generate a feature-based review-summary. Our second objective is to develop a predictive model to know the next week's product sales based on numerical review ratings and textual features embedded in the reviews. When it comes to product features, every user has different priorities for different features. To capture this aspect of decision-making, we have designed a new mechanism to generate a numerical rating for every feature of the product individually. The data have been collected from a well-known commercial website for two different products. The validation of the model is carried out using a crowd-sourcing technique.

  11. The Effect of Feed to Inoculums Ratio on Biogas Production Rate from Cattle Manure Using Rumen Fluid as Inoculums

    Directory of Open Access Journals (Sweden)

    S. Sunarso

    2010-12-01

    Full Text Available In this study, rumen fluid of animal ruminant was used as inoculums to increase biogas production rate from cattle manure at mesophilic condition. A series of laboratory experiments using 400 ml biodigester were performed in batch operation mode. Given 100 grams of fresh cattle manure was fed to each biodigester and mixed with rumen fluid and tap water resulting five different feed to inoculum (F/I ratios (i.e. 17.64, 23.51, 35.27, and 70.54. The operating temperatures were varied at room temperature. The results showed that the rumen fluid inoculated to biodigester significantly effected the biogas production. Rumen fluid inoculums caused biogas production rate and efficiency increase more than two times in compare to manure substrate without rumen fluid inoculums. At four F/Is tested, after 80 days digestion, the biogas yield were 191, 162, 144 and 112 mL/g VS, respectively. About 80% of the biogas production was obtained during the first 40 days of digestion. The best performance of biogas production will be obtained if F/I ratio is in the range of 17.64 to 35.27 (correspond to 25 – 50 % of rumen fluid. The future work will be carried out to study the dynamics of biogas production if both the rumen fluid inoculums and manure are fed in the continuous system

  12. Worker productivity and ventilation rate in a call center: Analyses of time-series data for a group of workers

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Geometrical α- and β-dose distributions and production rates of radiolysis products in water in contact with spent nuclear fuel

    Science.gov (United States)

    Nielsen, Fredrik; Jonsson, Mats

    2006-12-01

    A mathematical model for the dose distribution and production rates of radiolysis products in water surrounding spent nuclear fuel has been developed, based on the geometrical and energetic properties of radiation. The nuclear fuel particle is divided into layers, from which the radiation emits. The water is likewise divided into layers, where the doses are distributed. The doses are stored in vectors which are added to determine the total dose rate. A complete inventory with over 200 radionuclides has been used as input data for the model. The purpose of the model is to describe the geometrical dose distribution as a function of fuel age and burn-up, to be used as input data for kinetic modeling of the fuel dissolution. The results show that the β-dose contribution close to the spent fuel surface is negligible. Also, the variation in the relative α/β dose contribution between different ages and burn-ups is insignificant. The α- and β-dose rates vary between different burn-ups of the same age; the younger the fuel is, the larger is the difference. Exponential functions have been fitted to the relations between fuel age and average dose rate, giving useful expressions for determining average dose rates for fuel ages other than those covered in this work.

  14. Left Ventricular Wall Stress-Mass-Heart Rate Product and Cardiovascular Events in Treated Hypertensive Patients

    DEFF Research Database (Denmark)

    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...... 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...

  15. Designing Flexible GUI to Increase the Acceptance Rate of Product Data Management Systems in Industry

    CERN Document Server

    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...

  16. Photosynthetic characteristics and estimated growth rates indicate grazing is the proximate control of primary production in the equatorial Pacific

    Science.gov (United States)

    Cullen, John J.; Lewis, Marlon R.; Davis, Curtiss O.; Barber, Richard T.

    1992-01-01

    Macronutrients persist in the surface layer of the equatorial Pacific because the production of phytoplankton is limited; the nature of this limitation has yet to be resolved. Measurements of photosynthesis as a function of irradiance (P-I) provide information on the control of primary productivity, a question of great biogeochemical importance. Accordingly, P-I was measured in the equatorial Pacific along 150 deg W, during February-March 1988. Diel variability of P-I showed a pattern consistent with nocturnal vertical mixing in the upper 20 m followed by diurnal stratification, causing photoinhibition near the surface at midday. Otherwise, the distribution of photosynthetic parameters with depth and the stability of P-I during simulated in situ incubations over 2 days demonstrated that photoadaptation was nearly complete at the time of sampling: photoadaptation had not been effectively countered by upwelling or vertical mixing. Measurements of P-I and chlorophyll during manipulations of trace elements showed that simple precautions to minimize contamination were sufficient to obtain valid rate measurements and that the specific growth rates of phytoplankton were fairly high in situ, a minimum of 0.6/d. Diel variability of beam attenuation also indicated high specific growth rates of phytoplankton and a strong coupling of production with grazing. It appears that grazing is the proximate control on the standing crop of phytoplankton. Nonetheless, the supply of a trace nutrient such as iron might ultimately regulate productivity by influencing species composition and food-web structure.

  17. Exact master equation for a spin interacting with a spin bath: Non-Markovianity and negative entropy production rate

    Science.gov (United States)

    Bhattacharya, Samyadeb; Misra, Avijit; Mukhopadhyay, Chiranjib; Pati, Arun Kumar

    2017-01-01

    An exact canonical master equation of the Lindblad form is derived for a central spin interacting uniformly with a sea of completely unpolarized spins. The Kraus operators for the dynamical map are also derived. The non-Markovianity of the dynamics in terms of the divisibility breaking of the dynamical map and the increase of the trace distance fidelity between quantum states is shown. Moreover, it is observed that the irreversible entropy production rate is always negative (for a fixed initial state) whenever the dynamics exhibits non-Markovian behavior. In continuation with the study of witnessing non-Markovianity, it is shown that the positive rate of change of the purity of the central qubit is a faithful indicator of the non-Markovian information backflow. Given the experimental feasibility of measuring the purity of a quantum state, a possibility of experimental demonstration of non-Markovianity and the negative irreversible entropy production rate is addressed. This gives the present work considerable practical importance for detecting the non-Markovianity and the negative irreversible entropy production rate.

  18. MODELING COMMERCIAL PROCESSES AND CUSTOMER BEHAVIORS TO ESTIMATE THE DIFFUSION RATE OF NEW PRODUCTS

    Institute of Scientific and Technical Information of China (English)

    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.

  19. THE NEOWISE-DISCOVERED COMET POPULATION AND THE CO + CO{sub 2} PRODUCTION RATES

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, James M.; Stevenson, Rachel; Kramer, Emily; Mainzer, A. K.; Masiero, Joseph R.; Weissman, Paul R.; Nugent, Carrie R.; Sonnett, Sarah [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, MS 183-401, Pasadena, CA 91109 (United States); Grav, Tommy [Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395 (United States); Fernández, Yan R. [Department of Physics, University of Central Florida, 4000 Central Florida Blvd., P.S. Building, Orlando, FL 32816-2385 (United States); Cutri, Roc M.; Dailey, John W.; Masci, Frank J.; Blair, Nathan; Lucas, Andrew [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States); Meech, Karen J. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Dr., Manoa, HI 96822 (United States); Walker, Russel [Monterey Institute for Research in Astronomy, 200 Eighth Street, Marina, CA 93933 (United States); Lisse, C. M. [Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road Laurel, MD 20723-6099 (United States); McMillan, Robert S. [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Blvd., Kuiper Space Science Bldg. 92, Tucson, AZ 85721-0092 (United States); Wright, Edward L., E-mail: bauer@scn.jpl.nasa.gov [Department of Physics and Astronomy, University of California, P.O. Box 91547, Los Angeles, CA 90095-1547 (United States); Collaboration: WISE and NEOWISE Teams

    2015-12-01

    The 163 comets observed during the WISE/NEOWISE prime mission represent the largest infrared survey to date of comets, providing constraints on dust, nucleus size, and CO + CO{sub 2} production. We present detailed analyses of the WISE/NEOWISE comet discoveries, and discuss observations of the active comets showing 4.6 μm band excess. We find a possible relation between dust and CO + CO{sub 2} production, as well as possible differences in the sizes of long and short period comet nuclei.

  20. The NEOWISE-Discovered Comet Population and the CO+CO2 production rates

    CERN Document Server

    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.

  1. Products from the high temperature pyrolysis of RDF at slow and rapid heating rates

    OpenAIRE

    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 ...

  2. Effect of flaxseed supplementation rate and processing on the production, fatty acid profile, and texture of milk, butter, and cheese.

    Science.gov (United States)

    Oeffner, S P; Qu, Y; Just, J; Quezada, N; Ramsing, E; Keller, M; Cherian, G; Goddick, L; Bobe, G

    2013-02-01

    Health and nutrition professionals advise consumers to limit consumption of saturated fatty acids and increase the consumption of foods rich in n-3 fatty acids. Researchers have previously reported that feeding extruded flaxseed, which is high in C18:3n-3, improves the fatty acid profile of milk and dairy products to less saturated fatty acids and to more C18:3n-3. Fat concentrations in milk and butter decreased when cows were fed higher concentrations of extruded flaxseed. The objective of this study was to determine the optimal rate of flaxseed supplementation for improving the fatty acid profile without decreasing production characteristics of milk and dairy products. By using a double 5 × 5 Latin square design, 10 mid- to late-lactation Holstein cows were fed extruded (0, 0.91, 1.81, and 2.72 kg/d) and ground (1.81 kg/d) flaxseed as a top dressing for 2-wk periods each. At the end of each 2-wk treatment period, milk and serum samples were taken. Milk was subsequently manufactured into butter and fresh Mozzarella cheese. Increasing supplementation rates of extruded flaxseed improved the fatty acid profile of milk, butter, and cheese gradually to less saturated and atherogenic fatty acids and to more C18:3n-3 by increasing concentrations of C18:3n-3 in serum. The less saturated fatty acid profile was associated with decreased hardness and adhesiveness of refrigerated butter, which likely cause improved spreadability. Supplementation rates of extruded flaxseed did not affect dry matter intake of the total mixed ration, milk composition, and production of milk, butter, or cheese. Flaxseed processing did not affect production, fatty acid profile of milk, or texture of butter and cheese. Feeding up to 2.72 kg/d of extruded flaxseed to mid- to late-lactation Holstein cows may improve nutritional and functional properties of milk fat without compromising production parameters.

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    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 p...

  4. Setting the holding cost rates in a multi-product system with remanufacturing

    NARCIS (Netherlands)

    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. Selfing rate in an alfalfa seed production field pollinated with leafcutter bees

    Science.gov (United States)

    Self-pollination or “selfing” in autotetraploid alfalfa (Medicago sativa L.) (2n = 4x = 32) leads to severe inbreeding depression. Investigating selfing in alfalfa seed production may allow mitigation strategy development against potential negative impacts of selfing on varietal performance. Using m...

  6. High rate treatment of terephthalic acid production wastewater in a two-stage anaerobic bioreactor

    NARCIS (Netherlands)

    Kleerebezem, R.; Beckers, J.; Pol, L.W.H.; Lettinga, G.

    2005-01-01

    The feasibility was studied of anaerobic treatment of wastewater generated during purified terephthalic acid (PTA) production in two-stage upflow anaerobic sludge blanket (UASB) reactor system. The artificial influent of the system contained the main organic substrates of PTA-wastewater: acetate, be

  7. Shipboard measurements of phytoplankton production and solar-stimulated fluorescence rates in the northwest Atlantic

    Science.gov (United States)

    Stegmann, P. M.; Lewis, M. R.

    1997-06-01

    We present results from a cruise to the Canadian sub-arctic and the Scotian Shelf designed to evaluate optical methods for bio-optical estimation of primary productivity. Vertical profiles of temperature and chlorophyll showed much variability from one station to the next, while primary production (normalized to biomass) ranged from 0.4 to 1 gC gChl -1 h -1 near the surface and decreased with depth. We used the linear model of Stegmann et al. (1992) (in Journal of Geophysical Research97, 627-638) to examine the relationship between solar-stimulated fluorescence and primary production and to determine the variability of the ratio of the quantum yield of photosynthesis, Φ c to the quantum yield of fluorescence, Φ f. We found that (1) there was a clear relation between production and fluorescence; (2) diurnal variations contributed to the variability in and (3) ranged from 0.32 to 0.42 molC Ein -1. The range of Φ found in this study is similar to the one from the equatorial Pacific (Stegmann et al., 1992, in Journal of Geophysical Research97, 627-638), despite the fact that the environmental conditions in the two regions were very different from each other. We did not find an increase in Φ c Φ as temperature increased.

  8. Institutional Productivity Ratings and Publishing Trends in Nine Literacy Journals: 1972-2012

    Science.gov (United States)

    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…

  9. Polyhydroxyalkanoates in waste activated sludge enhances anaerobic methane production through improving biochemical methane potential instead of hydrolysis rate

    Science.gov (United States)

    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.

  10. Effects of temperature on rates and mineral products of microbial Fe(II) oxidation by Leptothrix cholodnii at microaerobic conditions

    Science.gov (United States)

    Vollrath, Susann; Behrends, Thilo; Koch, Christian Bender; Cappellen, Philippe Van

    2013-05-01

    Oxygen concentrations are important in constraining the geochemical niche of neutrophilic iron oxidizers. However, other factors like temperature may affect the competition between microbial and abiotic Fe(II) oxidation and may cause community changes. Here, rates and mineral products of Fe(II) oxidation (initial concentration 150 μmol Fe(II)/l) by the Fe(II) oxidizing bacterial strain Leptothrix cholodnii Appels were compared to those of abiotic oxidation in the temperature range 11-37 °C. Experiments were carried out in a batch reactor at 12-13 μmol O2/l (0.92-1% O2 saturation), pH 7 and, for the microbial experiments, a cell density of around 108 cells/ml. The iron precipitates formed at the different temperatures were characterized by SEM, XRD, FTIR and Mössbauer spectroscopy. Abiotic and microbial Fe(II) oxidation proceeded in two stages. During the initial stage, rates of microbial oxidation exhibited a temperature optimum curve. In contrast, the temperature dependency of abiotic Fe(II) oxidation rate followed the Arrhenius equation. As a consequence, microbial oxidation rates were about 10 times higher compared to the abiotic oxidation at 30 °C. During the second stage, microbial and abiotic rates and their temperature dependencies were similar. Independent of temperature or presence of bacteria, lepidocrocite and ferrihydrite were identified as reaction products, but the characteristics of the precipitates differed. At 37 °C, less lepidocrocite was precipitated in microbial and abiotic experiments due to high oxidation rates. Abiotic oxidation produced larger lepidocrocite crystals mixed with smaller, less crystalline oxides. Large crystals were absent in the microbial products, possibly due to growth inhibition of the minerals by EPS substances. Nevertheless, Mössbauer spectra revealed a better crystal structure of the smaller, microbial precipitates compared to the abiotically formed oxides.

  11. A High-Precision Determination of the Astrophysical Rate for Production of ^9Be

    Science.gov (United States)

    Arnold, C. W.; Clegg, T. B.; Karwowski, H. J.; Rich, G. C.; Tompkins, J. R.; Howell, C. R.

    2010-11-01

    New cross section measurements of the astrophysically important ^9Be(γ,n) reaction have been made from 1.5 to 5.18 MeV. The measurements were made using the nearly monoenergetic circularly polarized γ-ray beam at Triangle Universities Nuclear Laboratory's High Intensity γ-ray Source. Measurements over narrow resonances employed beams with energy spread dE/E <= 1%. The energy-dependent absolute efficiency of the neutron counter used in this work was measured to ± 3% accuracy. New resonance parameters for the 4 lowest lying states in ^9Be were determined. A new reaction rate for α+ α+ n has been determined to better than ± 5%. The present rate is ˜ 25% larger than two widely accepted rates [1-2] in the temperature range important for r-process nucleosynthesis. The implications of this new rate on r-process and nuclear abundance predictions will be discussed.[4pt] [1] C. Angulo et al. Nuc. Phys. A 656 (1999) 3-183. [0pt] [2] K. Sumiyoshi et al. Nuc. Phys A 709 (2002) 467-486.

  12. Impact of ventilation rates on SBS symptoms and productivity in offices

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Fanger, Povl Ole

    1999-01-01

    parameters remained unchanged. Ventilation was provided by an axial fan mounted in the window to avoid any potential pollution sources in a traditional HVAC system, and almost perfect mixing of air was provided at an air velocity below 0.2 m/s in the occupied zone. At each ventilation rate, 30 female...

  13. Rental prices, rates of return, capital aggregation and productivity : Evidence from EU and US

    NARCIS (Netherlands)

    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

  14. The Influence of Photolysis Rate Constants in Ozone Production for the Paso del Norte Region

    Science.gov (United States)

    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.

  15. Neutron production rates by inverse-beta decay in fully ionized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Maiani, L.; Polosa, A.D.; Riquer, V. [Sapienza Universita di Roma, Dipartimento di Fisica (Italy); INFN, Rome (Italy)

    2014-04-15

    Recently we showed that the nuclear transmutation rates are largely overestimated in the Widom-Larsen theory of the so-called 'Low Energy Nuclear Reactions'. Here we show that unbound plasma electrons are even less likely to initiate nuclear transmutations. (orig.)

  16. Production of Candida utilis Biomass and Intracellular Protein Content: Effect of Agitation Speed and Aeration Rate

    Directory of Open Access Journals (Sweden)

    Rosma, A.

    2006-01-01

    Full Text Available 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, 500, 700 and 900 rpm was employed. The highest yield of protein content (1.2 g/L media and total biomass (7.8 g/L media were resulted from yeast cultivation with agitation speed of 900 rpm. Thus, the effects of aeration rate (0.5, 1.0, 2.0 and 3.0 L/min were studied at agitation speed of 900 rpm. A maximum yield of protein content (1.6 g/L media and biomass (9.5 g/L media were attained at aeration rate of 2.0 L/min.

  17. Heliocentric distance dependencies of the C2 lifetime and C2 parent production rate in comet P/Brorsen-Metcalf (1989o)

    Science.gov (United States)

    Lazzarin, M.; Tozzi, Giau Paolo; Barbieri, C.; Festou, Michel C.

    1992-01-01

    Comet P/Brorsen-Metcalf (1989o) has been extensively observed in the visible and in the ultraviolet during its latest apparition of summer 1989. In this paper we report a preliminary determination of the C2 production rates and lifetimes and we compare those rates to the H2O production rates obtained from UV data.

  18. Importance of anisotropy in detachment rates for force production and cargo transport by a team of motor proteins.

    Science.gov (United States)

    Takshak, Anjneya; Kunwar, Ambarish

    2016-05-01

    Many cellular processes are driven by collective forces generated by a team consisting of multiple molecular motor proteins. One aspect that has received less attention is the detachment rate of molecular motors under mechanical force/load. While detachment rate of kinesin motors measured under backward force increases rapidly for forces beyond stall-force; this scenario is just reversed for non-yeast dynein motors where detachment rate from microtubule decreases, exhibiting a catch-bond type behavior. It has been shown recently that yeast dynein responds anisotropically to applied load, i.e. detachment rates are different under forward and backward pulling. Here, we use computational modeling to show that these anisotropic detachment rates might help yeast dynein motors to improve their collective force generation in the absence of catch-bond behavior. We further show that the travel distance of cargos would be longer if detachment rates are anisotropic. Our results suggest that anisotropic detachment rates could be an alternative strategy for motors to improve the transport properties and force production by the team.

  19. Using short pulses to enhance the production rate of vibrationally excited hydrogen molecules in hydrogen discharge

    Institute of Scientific and Technical Information of China (English)

    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.

  20. Optimum fertilizer rate for kangkong (Ipomoea reptans L.) production in ultisol Jasinga

    OpenAIRE

    Anas D Susila; T. Prasetyo; Kartika, J.G.

    2008-01-01

    Proper fertilization of a crop is knowing the crop nutrient requirement for production of maximum yield and the potential level of nutrient availability from the soil. In addition to yield obtained, quality of the commodity is an important factor of profit and shelf-life for high-value crops. Nitrogen, phosphor, and potassium availability are the most limiting factors for maximum growth and yield. Kangkong (Ipomoea reptans L.) are important traditional leafy vegetables crops cultivated in Ind...

  1. Production and release rate of (37)Ar from the UT TRIGA Mark-II research reactor.

    Science.gov (United States)

    Johnson, Christine; Biegalski, Steven R; Artnak, Edward J; Moll, Ethan; Haas, Derek A; Lowrey, Justin D; Aalseth, Craig E; Seifert, Allen; Mace, Emily K; Woods, Vincent T; Humble, Paul

    2017-02-01

    Air samples were taken at various locations around The University of Texas at Austin's TRIGA Mark II research reactor and analyzed to determine the concentrations of (37)Ar, (41)Ar, and (133)Xe present. The measured ratio of (37)Ar/(41)Ar and historical records of (41)Ar releases were then utilized to estimate an annual average release rate of (37)Ar from the reactor facility. Using the calculated release rate, atmospheric transport modeling was performed in order to determine the potential impact of research reactor operations on nearby treaty verification activities. Results suggest that small research reactors (∼1 MWt) do not release (37)Ar in concentrations measurable by currently proposed OSI detection equipment.

  2. Temperature and strain rate effects on the piezoelectric charge production of PZT 95/5

    Science.gov (United States)

    Khan, Amnah S.; Proud, William G.

    2017-01-01

    To develop a better understanding of the piezoelectric ceramic lead zirconate titanate (PZT) 95/5, parameters including varying temperatures, porosities and strain rates have been studied. The effects on the charge output and fracture of poled PZT samples of different porosities have been investigated with compressive strain rates (10-4 - 10+3 s-1) using quasi-static loading equipment, drop-weight towers and Split Hopkinson Pressure Bars (SHPBs). The cylindrical specimens were of 4.4 mm diameter, thickness 0.8 - 4.4 mm, and density 7.3 - 8.3 g cm-3. The temperature range of -20 °C to +80 °C was achieved using purpose-built environmental chambers. The resulting stress-strain relationships are compared; all the samples ultimately displayed a brittle response at failure [1].

  3. Estimating the carbon sequestration capacity of shale formations using methane production rates.

    Science.gov (United States)

    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.

  4. In Situ Measurement of Local Hydrogen Production Rate by Bubble-Evolved Recording

    OpenAIRE

    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 ...

  5. Dispensing Rates of Four Common Hearing Aid Product Features: Associations With Variations in Practice Among Audiologists

    OpenAIRE

    Johnson, Earl E.; Ricketts, Todd A.

    2010-01-01

    The purpose of the study was to develop and examine a list of potential variables that may account for variability in the dispensing rates of four common hearing aid features. A total of 29 potential variables were identified and placed into the following categories: (1) characteristics of the audiologist, (2) characteristics of the hearing aids dispensed by the audiologist, (3) characteristics of the audiologist's patient population, and (4) evidence-based practice grades of recommendation f...

  6. The devil you know: The effect of brand recognition and product ratings on consumer choice

    Directory of Open Access Journals (Sweden)

    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.

  7. Shock Tube Measurement of the High-Temperature Rate Constant for OH + CH3 → Products.

    Science.gov (United States)

    Wang, Shengkai; Li, Sijie; Davidson, David F; Hanson, Ronald K

    2015-08-20

    The reaction between hydroxyl (OH) and methyl radicals (CH3) is critical to hydrocarbon oxidation. Motivated by the sparseness of its high-temperature rate constant data and the large uncertainties in the existing literature values, the current study has remeasured the overall rate constant of the OH + CH3 reaction and extended the measurement temperature range to 1214-1933 K, using simultaneous laser absorption diagnostics for OH and CH3 radicals behind incident and reflected shock waves. tert-Butyl hydroperoxide and azomethane were used as pyrolytic sources for the OH and CH3 radicals, respectively. The current study bridged the temperature ranges of existing experimental data, and good agreement is seen between the current measurement and some previous experimental and theoretical high-temperature studies. A recommendation for the rate constant expression of the title reaction, based on the weighted average of the high-temperature data from selected studies, is given by k1 = 4.19 × 10(1)(T/K)(3.15) exp(5270 K/T) cm(3) mol(-1) s(-1) ±30%, which is valid over 1000-2500 K.

  8. Effect of seed rate and row spacing in seed production of Festulolium

    DEFF Research Database (Denmark)

    Deleuran, L C; Gislum, R; Boelt, B

    2010-01-01

    in seed yield. No effect of row spacing on seed yield was observed in Paulita. Neither of the two types was affected in seed yield by seed rate. The fact that row spacing in both types can be increased to 24 cm without having a concomitant negative effect on seed yield implies that mechanical weed control......-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...

  9. Measurement of HO{sub x}{center_dot} production rate due to radon decay in air

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Subthalamic nucleus and internal globus pallidus scale with the rate of change of force production in humans.

    Science.gov (United States)

    Vaillancourt, David E; Mayka, Mary A; Thulborn, Keith R; Corcos, Daniel M

    2004-09-01

    The basal ganglia, motor cortex, and cerebellum have been implicated as a circuit that codes for movement velocity. Since movement velocity covaries with the magnitude of force exerted and previous studies have shown that similar regions scale in activation for velocity and force, the scaling of neuronal activity with movement velocity could be due to the force exerted. The present study implemented a parametric functional magnetic resonance imaging (fMRI) design to determine which brain regions directly scale with the rate of change of force production, independent of the magnitude of force exerted. Nine healthy adults produced force with their right middle finger and thumb at 25% of their maximal voluntary contraction across four conditions: (1) fast pulse, (2) fast hold, (3) medium hold, and (4) slow hold. There were three primary findings: (i) the activation volume in multiple regions increased with the duration of the force contraction, (ii) only the activation volume in the bilateral internal globus pallidus and left subthalamic nucleus parametrically scaled with the rate of change of force production, and (iii) there was an inverse relation between the activation volume in the subthalamic nucleus and internal globus pallidus with the rate of change of force production. The current findings are the first to have used neuroimaging techniques in humans to segregate the functional anatomy of the internal globus pallidus from external globus pallidus, distinguish functional activation in the globus pallidus from the putamen, and demonstrate task-dependent scaling in the subthalamic nucleus and internal globus pallidus. We conclude that fast, ballistic force production is preprogrammed, requiring a small metabolic demand from the basal ganglia. In contrast, movements that require the internal regulation of the rate of change of force are associated with increased metabolic demand from the subthalamic nucleus and internal segment of the globus pallidus.

  11. Impact of organic loading rate on biohydrogen production in an up-flow anaerobic packed bed reactor (UAnPBR).

    Science.gov (United States)

    Ferraz, Antônio Djalma Nunes; Zaiat, Marcelo; Gupta, Medhavi; Elbeshbishy, Elsayed; Hafez, Hisham; Nakhla, George

    2014-07-01

    This study assesses the impact of organic loading rate on biohydrogen production from glucose in an up-flow anaerobic packed bed reactor (UAnPBR). Two mesophilic UAPBRs (UAnPBR1 and 2) were tested at organic loading rates (OLRs) ranging from 6.5 to 51.4 g COD L(-1)d(-1). To overcome biomass washout, design modifications were made in the UAnPBR2 to include a settling zone to capture the detached biomass. The design modifications in UAnPBR2 increased the average hydrogen yield from 0.98 to 2.0 mol-H2 mol(-1)-glucose at an OLR of 25.7 g COD L(-1)d(-1). Although, a maximum hydrogen production rate of 23.4 ± 0.9 L H2 L(-1)d(-1) was achieved in the UAnPBR2 at an OLR of 51.4 g COD L(-1)d(-1), the hydrogen yield dropped by 50% to around 1 mol-H2 mol(-1)-glucose. The microbiological analysis (PCR/DGGE) showed that the biohydrogen production was due to the presence of the hydrogen and volatile acid producers such as Clostridium beijerinckii, Clostridium butyricum, Megasphaera elsdenii and Propionispira arboris.

  12. Comparison of methods to measure the rate of neutral free radical production by photo-deionization of negative ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Keiji E-mail: khayashi@neptune.kanazawa-it.ac.jp; Konno, Hiroshi; Oseki, Takashi; Kojima, Hideki; Kanayama, Takuo

    2003-05-01

    Two measurement methods to determine the rate of neutral free radical production by the photo-deionization of negative ion beams (PDINIB) are introduced. These methods, namely, photoelectron-current measurement by low-frequency electro-modulation probe (PMMP) and measurement of decrease in the negative-ion beam current (DNIC) were 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 (RBNR) produced by the PDINIB procedure. A {sup 63}Cu{sup -} negative ion beam of kinetic energy E{sub i} varied up to 15 keV was irradiated with a 514.5 nm visible light beam from a 25 W CW Ar{sup +} ion laser. The detection limit of the production rate by the PMMP setup was as high as 6 x 10{sup 9} s{sup -1} under the condition that E{sub i}=15 keV, the negative-ion beam current I{sub i}=4 {mu}A and the laser power P=6 W. The DNIC method is simpler but less reliable than the PMMP method owing to larger uncertainty resulting from the fluctuation of the negative-ion beam current.

  13. Power Spectrum Analyses of Nuclear Decay Rates

    CERN Document Server

    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. Effects of pH and carbonate concentration on dissolution rates of the lead corrosion product PbO(2).

    Science.gov (United States)

    Xie, Yanjiao; Wang, Yin; Singhal, Vidhi; Giammar, Daniel E

    2010-02-01

    Lead(IV) oxide is a corrosion product that can develop on lead pipes and affect lead concentrations in drinking water. Continuously stirred flow-though reactors were used to quantify the dissolution rates of plattnerite (beta-PbO(2)) at different pH values and dissolved inorganic carbon (DIC) concentrations. Organic pH buffers were not used, because several were found to be reductants for PbO(2) that accelerated its dissolution. Most plattnerite dissolution rates were on the order of 10(-10) mol/min-m(2). The rate of dissolution increased with decreasing pH and with increasing DIC. The effect of DIC is consistent with a reductive dissolution mechanism that involves the reduction of Pb(IV) to Pb(II) at the plattnerite surface followed by the formation of soluble Pb(II)-carbonate complexes that accelerate Pb(II) release from the surface. Under the experimental conditions, dissolved lead concentrations were controlled by the dissolution rate of plattnerite and not by its equilibrium solubility. A dissolution rate model was developed and can be used to predict dissolution rates of plattnerite as a function of pH and DIC.

  15. In vitro fermentation profiles, gas production rates, and microbiota modulation as affected by certain fructans, galactooligosaccharides, and polydextrose.

    Science.gov (United States)

    Hernot, David C; Boileau, Thomas W; Bauer, Laura L; Middelbos, Ingmar S; Murphy, Michael R; Swanson, Kelly S; Fahey, George C

    2009-02-25

    It is of interest to benefit from the positive intestinal health outcomes of prebiotic consumption but with minimal gas production. This study examined gas production potential, fermentation profile, and microbial modulation properties of several types of oligosaccharides. Substrates studied included short-chain, medium-chain, and long-chain fructooligosaccharides, oligofructose-enriched inulin, galactooligosaccharide, and polydextrose. Each substrate was fermented in vitro using human fecal inoculum, and fermentation characteristics were quantified at 0, 4, 8, and 12 h. Gas and short-chain fatty acid (SCFA) production data showed that short-chain oligosaccharides were more rapidly fermented and produced more SCFA and gas than substrates with greater degrees of polymerization. Lactobacilli increased similarly among substrates. Short-chain oligosaccharides fermentation resulted in the greatest increase in bifidobacteria concentrations. Mixing short- and long-chain oligosaccharides attenuated short-chain oligosaccharide fermentation rate and extent. This study provides new information on the fermentation characteristics of some oligosaccharides used in human nutrition.

  16. Production, chemical composition and stocking rate of forage systems compounds for coastcross-1 intercropped with ryegrass and clovers

    Directory of Open Access Journals (Sweden)

    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.

  17. Production and Trade Situation in Iran and USA and Impact of Exchange rate Volatility on the Exports

    Directory of Open Access Journals (Sweden)

    M. Salarpour

    2015-05-01

    Full Text Available In the present study, pistachio production and trade and influential factors on its exports in Iran and the USA are compared the the .Using the annual data from 1970 to 2011; this study aimed to analyze the effects of pistachio price and the effects of food security. Moreover, the relationship between exchange rate and pistachio export in the Iranian economy was analyzed through examining a non linear relation between the two factors. Therefore, the hypothesis validation upon nonlinearity relationship between exchange rate and pistachio export was analyzed using smooth transition autoregressive model (STAR. The results of smooth transition model (STAR show that there is a nonlinear Granger causality between exchange rate and pistachio export and vice versa. It is therefore recommended ,in order to determine the threshold level of potential benefits of pistachio exports, the existence of the nonlinear relationship between the dynamic exchange rate and pistachio exports should be considered. Furthermore, in order to maintain market share in the international level, understanding target markets of export and achieving complete information upon the position of the major competitors in the production and trade of Pistachio is essential.

  18. Development rate and brood production in haplo- and pleometrotic colonies of Oecophylla smaragdina

    DEFF Research Database (Denmark)

    Offenberg, Joachim; Peng, Renkang; Nielsen, Mogens Gissel

    2012-01-01

    until the first worker emerges may shorten. For territorial species and species that rob brood from neighbouring colonies, a faster production of more workers may improve the chance of surviving intraspecific competition. In this study, the time from the nuptial flight to the emergence of the first...... with development time, showing that earlier development of the first worker increased queen fecundity. These results indicate that pleometrotic O. smaragdina colonies are competitively superior to haplometrotic colonies as they produce more workers faster and shorten the claustral phase, leading to increased queen...

  19. A New Process for Hot Metal Production at Low Fuel Rate - Phase 1 Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Aquaponics: integrating fish feeding rates and ion waste production for strawberry hydroponics

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. UNAVCO GPS High-Rate and Real-Time Products and Services: Building a next generation geodetic network.

    Science.gov (United States)

    Mencin, David; Meertens, Charles; Mattioli, Glen; Feaux, Karl; Looney, Sara; Sievers, Charles; Austin, Ken

    2013-04-01

    Recent advances in GPS technology and data processing are providing position estimates with centimeter-level precision at high-rate (1-5 Hz) and low latency (seismic, volcanic, magmatic and tsunami deformation sources, and moreover profoundly transforming rapid event characterization, early warning, as well as hazard mitigation and response. Other scientific and operational applications for high-rate GPS also include glacier and ice sheet motions, tropospheric modeling, and better constraints on the dynamics of space weather. UNAVCO, through community input and the recent Plate Boundary Observatory (PBO) NSF-ARRA Cascadia initiative, has nearly completed the process of upgrading a total of 373 PBO GPS sites to real-time high-rate capability and these streams are now being archived in the UNAVCO data center. Further, through the UNAVCO core proposal (GAGE), currently under review at NSF, UNAVCO has proposed upgrading a significant portion of the ~1100 GPS stations that PBO currently operates to real-time high-rate capability to address community science and operational needs. In addition, in collaboration with NOAA, 74 of these stations will provide meteorological data in real-time, primarily to support watershed and flood analyses for regional early-warning systems related to NOAA's work with California Department of Water Resources. In preparation for this increased emphasis on high-rate GPS data, UNAVCO hosted an NSF funded workshop in Boulder, CO on March 26-28, 2012, which brought together 70 participants representing a spectrum of research fields with a goal to develop a community plan for the use of real-time GPS data products within the UNAVCO and EarthScope communities. These data products are expected to improve and expand the use of real-time, high-rate GPS data over the next decade.

  2. Cued Speech Transliteration: Effects of Speaking Rate and Lag Time on Production Accuracy.

    Science.gov (United States)

    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.

  3. Mass production of graphene nanoscrolls and their application in high rate performance supercapacitors.

    Science.gov (United States)

    Zheng, Bingna; Xu, Zhen; Gao, Chao

    2016-01-21

    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 m(2) 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).

  4. A reduction in growth rate of Pseudomonas putida KT2442 counteracts productivity advances in medium-chain-length polyhydroxyalkanoate production from gluconate

    Directory of Open Access Journals (Sweden)

    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. Influence of hydrologic loading rate on phosphorus retention and ecosystem productivity in created wetlands. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mitsch, W.J.; Cronk, J.K.

    1995-01-01

    Four 2- to 3-ha constructed freshwater riparian wetlands in Lake County, Illinois, were subjected to two hydrologic regimes of pumped river water to simulate nonpoint source pollution. The experimental wetlands at the Des Plaines River Wetland Demonstration Project were designed to develop and test wetland design principles, construction methods, and management programs needed to create and maintain wetlands for the purposes of water quality management, flood control, and fish and wildlife habitat. High-flow wetlands (HFW) with short retention times received 34 to 38 cm of river water per week, and low-flow wetlands (LFW) with high retention times received 10 to 15 cm per week. This report summarizes research results for phosphorus dynamics and retention, macrophyte development, periphyton productivity, and overall water column metabolism through 1992. All of these functions were hypothesized to be related to hydrologic conditions.

  6. ISOLATION RATE OF PATHOGENIC BACTERIA FROM SOME FOOD PRODUCTS IN TEHRAN

    Directory of Open Access Journals (Sweden)

    H. Salari

    2000-12-01

    Full Text Available Bacteria usually cause disease in the gastrointestinal tract by colonization and growth in the gastrointestinal tract, where the micro organisms may invade the tissues of host or secretion of an exotoxin that is performed in food and then ingested by the host, examples of second group include: staphylococcal, Bacillus cereus, clostridial (C.botulinum and C.perfringens type A toxin. In this study pathogenic bacteria of 350 food products by culture method were investigated. The results were obtained as follows: Bacillus cereus 12 cases (3.4, Staphylococcus coagulase positive 25(7.1%, Staphylococcus coagulase negative 37 (10.6%, Streptococcus alpha hemolysis 18 (5.1%, Enterococcus 3(0.8% and Klebsiella 5(1.4%.

  7. Decalactone production by Yarrowia lipolytica under increased O2 transfer rates.

    Science.gov (United States)

    Aguedo, M; Gomes, N; Garcia, E Escamilla; Waché, Y; Mota, M; Teixeira, J A; Belo, I

    2005-10-01

    Yarrowia lipolytica converts methyl ricinoleate to gamma-decalactone, a high-value fruity aroma compound. The highest amount of 3-hydroxy-gamma-decalactone produced by the yeast (263 mg l(-1)) occurred by increasing the k(L)a up to 120 h(-1) at atmospheric pressure; above it, its concentration decreased, suggesting a predominance of the activity of 3-hydroxyacyl-CoA dehydrogenase. Cultures were grown under high-pressure, i.e., under increased O(2) solubility, but, although growth was accelerated, gamma-decalactone production decreased. However, by applying 0.5 MPa during growth and biotransformation gave increased concentrations of dec-2-en-4-olide and dec-3-en-4-olide (70 mg l(-1)).

  8. Intake and milk production of goats grazing Sulla forage under different stocking rates

    Directory of Open Access Journals (Sweden)

    M. L. Alicata

    2010-04-01

    Full Text Available A total of 24 Girgentana goats was divided into 3 homogeneous groups grazing a sulla monoculture under stocking rate of 30, 50 or 70 goats/ha (LSR, MSR and HSR. Available biomass, herbage selected by goats and milk yield were measured and sampled. The DM intake of goats and its botanic composition and digestibility were assessed by the n-alkane method. Grazing at HSR was suspended 18 d before MSR and LSR (35 vs. 53 d, due to the low biomass availability. Over the first 35 d of grazing, the HSR reduced height and availability of herbage. The herbage intake and milk yield of goats increased from HSR to LSR, without relevant changes in milk quality. During all grazing period (53 d, the higher grazing pressure led to a lower total milk yield per goat, whereas the HSR produced the highest daily and total milk amount per ha.

  9. Polar coralline algal CaCO3-production rates correspond to intensity and duration of the solar radiation

    Directory of Open Access Journals (Sweden)

    S. Teichert

    2013-08-01

    Full Text Available In this study we present a comparative quantification of CaCO3 production rates by rhodolith-forming coralline red algal communities situated in high polar latitudes and assess which environmental parameters control these productions rates. The present rhodoliths act as ecosystem engineers and their carbonate skeletons provide an important ecological niche to a variety of benthic organisms. The settings are distributed along the coasts of the Svalbard archipelago, being Floskjeret (78°18' N in Isfjorden, Krossfjorden (79°08' N at the eastern coast of Haakon VII Land, Mosselbukta (79°53' N at the eastern coast of Mosselhalvøya, and Nordkappbukta (80°31' N at the northern coast of Nordaustlandet. All sites feature Arctic climate and strong seasonality. The algal CaCO3 production rates were calculated from fuchsine stained annual growth increments exhibited by the rhodoliths and range from 100.9 g (CaCO3 m−2 yr−1 at Nordkappbukta to 200.3 g (CaCO3 m−2 yr−1 at Floskjeret. The rates correlate to various environmental parameters with geographical latitude being the most significant (negative correlation, R2 = 0.95, p R2 = 0.93, p R2 = 0.87, p = 0.07, and the annual mean temperature (positive correlation, R2 = 0.48, p < 0.05. This points out sufficient light incidence to be the main control of the growth of the examined coralline red algal rhodolith communities, while temperature is less important. Thus, the ongoing global change with its rising temperatures will most likely result in impaired conditions for the algal, because the concomitant increased global runoff will decrease water transparency and hence light incidence at the four offshore sites. Regarding the aforementioned role of the rhodoliths as ecosystem engineers, the impact on the associated organisms will presumably also be negative.

  10. New historical records and relationships among 14C production rates, abundance and color of low latitude auroras and sunspot abundance

    Science.gov (United States)

    Abbott, Dallas; Juhl, Robert

    2016-12-01

    Incursions of high-energy particles from space, specifically solar energetic particles and galactic cosmic rays, have significant effects on the Earth, including disruption of the Earth's magnetic field, generation of electric fields strong enough to damage electronic devices as well as the production of auroras at low-latitudes, within 45° of the magnetic equator. We examine the relationships among 14C production, auroral abundance, auroral color and sunspot abundance using existing data supplemented by a new dataset. The new dataset, based on Chinese and Korean records from A.D. 1100-1700, includes 46 new or revised records of sunspots and 279 records of low-latitude auroras. Low-latitude auroras are predominantly red (66%, 835 events) with lesser proportions of white (20%, 253 events) and black auroras (6%, 67 events). All other auroral colors (green, yellow, multicolored, blue and purple) aggregate to a total of 100 events (8%). Overall, white auroras are more frequent during times of higher 14C production. We use two empirical methods of evaluating the flux of high-energy particles: modeled peaks and lows in 14C production and peaks and lows in the 14C calibration curve. We find that comparison to modeled 14C production gives significant results. White auroras are significantly more abundant (98% probability) at times of high production of 14C. Red auroras are somewhat more abundant (88% probability) at times of low production of 14C. The abundances of black, multicolored, green, yellow, and blue auroras between times of low and high 14C production are not significantly different. Violet/purple auroras are significantly more abundant (98% probability) at times of low 14C production. The positive correlation of violet/purple auroras with times of low14C production rate and the lack of correlation of blue auroras with times of high14C production is surprising, for this portion of the visible spectrum contains strong emission lines and some lines with high

  11. Broken R parity contributions to flavor changing rates and CP asymmetries in fermion pair production at leptonic colliders

    Science.gov (United States)

    Chemtob, M.; Moreau, G.

    1999-06-01

    We examine the effects of the R parity odd renormalizable interactions on flavor changing rates and CP asymmetries in the production of fermion-antifermion pairs at leptonic (electron and muon) colliders. In the reactions l-+l+-->fJ+f¯J' (l=e, μ J≠J') the produced fermions may be leptons, down quarks, or up quarks, and the center of mass energies may range from the Z-boson pole up to 1000 GeV. Off the Z-boson pole, the flavor changing rates are controlled by tree level amplitudes and the CP asymmetries by interference terms between tree and loop level amplitudes. At the Z-boson pole, both observables involve loop amplitudes. The lepton number violating interactions, associated with the coupling constants λijk, λ'ijk, are only taken into account. The consideration of loop amplitudes is restricted to the photon and Z-boson vertex corrections. We briefly review flavor violation physics at colliders. We present numerical results using a single, species and family independent, mass parameter m~ for all the scalar superpartners and considering simple assumptions for the family dependence of the R parity odd coupling constants. Finite nondiagonal rates (CP asymmetries) entail nonvanishing products of two (four) different coupling constants in different family configurations. For lepton pair production, the Z-boson decays branching ratios BJJ'=B(Z-->l-J+l+J') scale in order of magnitude as BJJ'~(λ/0.1)4(100 GeV/m~)2.510-9, with coupling constants λ=λijk or λ'ijk in appropriate family configurations. The corresponding results for d- and u quarks are larger, due to an extra color factor Nc=3. The flavor nondiagonal rates, at energies well above the Z-boson pole, slowly decrease with the center of mass energy and scale with the mass parameter approximately as σJJ'~(λ/0.1)4(100 GeV/m~)2-3(1-10) fbarn. Including the contributions from an sneutrino s-channel exchange could raise the rates for leptons or d quarks by one order of magnitude. The CP-odd asymmetries at

  12. Skeletonema cf. costatum biogenic silica production rate determinated by PDMPO method

    Science.gov (United States)

    Zhang, Guicheng; Leng, Xiaoyun; Feng, Yuanyuan; Li, Xia; Sun, Jun

    2017-04-01

    Diatoms are the only ecological phytoplankton that require silicic acid for growth. They are also the dominant contributor of ocean's total primary productivity. Generation and circulation with silica walls, which the siliceous organisms form, is an important component of the marine biological pump. It is crucial to the study of the operational mechanisms of biological pump with different sea areas. Moreover, it is the key link to the study of global silicon cycle. This paper introduces the basic mechanism of the formation of diatom silica walls and a new way of researching silicic acid metabolism, namely the 2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)- methoxy)phenyl)oxazole (PDMPO) dyeing method. Under a fluorescence microscope after excitation with bright green fluorescence, it can combine with silicic acid to form a complex into the Si deposition within diatom cells. The advantage of this method is that it can monitor the metabolism of silicate after adding PDMPO. For experimentation and sample collection in each of the specified time points, samples were determinated through the unutilized silicic acid, silica dissoluble intracellular and Si deposition within diatom cells, not only using hot alkaline digestions method but also PDMPO dyeing method. Results showed a good linear relationship between PDMPO fluorescent value and biogenic silica concentration. It was also indicated that PDMPO had no deleterious impact on Skeletonema cf. costatum growth for 34 h and was useful for tracking newly-deposited biogenic silica in diatoms' frustules.

  13. Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability.

    Science.gov (United States)

    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.

  14. 2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, Michael T., E-mail: michael.montgomery@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Coffin, Richard B., E-mail: richard.coffin@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Boyd, Thomas J., E-mail: thomas.boyd@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Smith, Joseph P., E-mail: joseph.smith@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Walker, Shelby E., E-mail: Shelby.Walker@noaa.gov [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Osburn, Christopher L., E-mail: chris_osburn@ncsu.edu [Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695 (United States)

    2011-12-15

    The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO{sub 2}); 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 CO{sub 2} was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/-38 {mu}g C kg{sup -1} d{sup -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 CO{sub 2} 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 CO{sub 2} is a common feature of natural bacterial assemblages in coastal sediment.

  15. Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability

    Directory of Open Access Journals (Sweden)

    Pietro Randelli

    2016-01-01

    Full Text Available 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.

  16. Lipogems Product Treatment Increases the Proliferation Rate of Human Tendon Stem Cells without Affecting Their Stemness and Differentiation Capability

    Science.gov (United States)

    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

  17. A Three-Stage Optimization Algorithm for the Stochastic Parallel Machine Scheduling Problem with Adjustable Production Rates

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2013-01-01

    Full Text Available We consider a parallel machine scheduling problem with random processing/setup times and adjustable production rates. The objective functions to be minimized consist of two parts; the first part is related with the due date performance (i.e., the tardiness of the jobs, while the second part is related with the setting of machine speeds. Therefore, the decision variables include both the production schedule (sequences of jobs and the production rate of each machine. The optimization process, however, is significantly complicated by the stochastic factors in the manufacturing system. To address the difficulty, a simulation-based three-stage optimization framework is presented in this paper for high-quality robust solutions to the integrated scheduling problem. The first stage (crude optimization is featured by the ordinal optimization theory, the second stage (finer optimization is implemented with a metaheuristic called differential evolution, and the third stage (fine-tuning is characterized by a perturbation-based local search. Finally, computational experiments are conducted to verify the effectiveness of the proposed approach. Sensitivity analysis and practical implications are also discussed.

  18. EFFECT OF DIFFERENT PROBIOTIC BACTERIA ON SURVIVAL RATE, GROWTH, AND PRODUCTION OF WHITELEG SHRIMP IN TRADITIONAL-PLUS TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Muharijadi Atmomarsono

    2015-06-01

    Full Text Available Instead of culturing tiger shrimp that is frequently burdened by mass mortality, whiteleg shrimp (Litopenaeus vannamei is then considered as an alternative commodity in Indonesian brackishwater ponds. To prevent the whiteleg shrimp from diseases, different probiotic bacteria were tested in completely randomized design experiment using nine 250 m2 experimental ponds stocked with 10 PLs of whiteleg shrimp fry/m2. Three treatments were applied, namely A alternate use of probiotic bacteria RICA-1, RICA-2, RICA-3; B alternate use of probiotic bacteria RICA-4, RICA-5, RICA-3, and C control (without probiotic bacteria; each with three replications. After 11-week application, the results showed that the best survival rate of whiteleg shrimp was achieved by treatment B 98.83% and the best production was achieved by treatment A (23.52 kg/250 m2. However, there were no significant differences (P>0.05 among the three treatments tested for the shrimp survival rate. The whiteleg shrimp production in treatment A and B were signicantly better (P<0.05 than that in treatment C (control. These high shrimp production in treatment A and B were mainly caused by the capability of the applied probiotics in controlling some water quality variables and Vibrio numbers.

  19. Galactic star-formation rates gauged by stellar end-products

    CERN Document Server

    Persic, M

    2006-01-01

    Young galactic X-ray point sources (XPs) closely trace the ongoing star formation in galaxies. From measured XP number counts we extract the collective 2-10 keV luminosity of young XPs, L_yXP, which we use to gauge the current star-formation rate (SFR) in galaxies. We find that, for a sample of local star-forming galaxies (i.e., normal spirals and mild starbursts), L_yXP correlates linearly with the SFR over three decades in luminosity. A separate, high-SFR sample of starburst ULIRGs can be used to check the calibration of the relation. Using their (presumably SF-related) total 2-10 keV luminosities we find that these sources satisfy the SFR-L_yXP relation, as defined by the weaker sample, and extend it to span about 5 decades in luminosity. The SFR-L_yXP relation is likely to hold also for distant Hubble Deep Field North galaxies, especially so if these high-SFR objects are similar to the (more nearby) ULIRGs. It is argued that the SFR-L_yXP relation provides the most adequate X-ray estimator of instantaneou...

  20. Implications of inflorescence clustering for the visitation rate by hummingbirds and fruit production by Heliconia bihai (L. L. (Heliconiaceae

    Directory of Open Access Journals (Sweden)

    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.

  1. Estimation and Forecasting the Gross Domestic Product´s Growth Rate in Ecuador: a Short-term Vision

    Directory of Open Access Journals (Sweden)

    Yadier Alberto Torres−Sánchez

    2017-01-01

    Full Text Available Ecuador is the seventh largest economy in Latin America. From 2000 to 2012, the country has been expanding at an average rate of 1,15 % on a quarter over quarter basis, mostly due to a rise in exports. Ecuador´s economy is highly dependent on oil exports. In order to reach its full growth potential, the country needs to reduce its dependence on oil revenue; increase the tax base; achieve political stability and reduce the levels of poverty and inequality. The main objective of this research is specifically marked in estimate and forecast the Gross Domestic Product´s Growth Rate in Ecuador, applying for this Box – Jenkins´ Methodology for ARIMA models. It was obtained a forecast of 3,96 % approximately, that represents a logical result according with the time series.

  2. Influence of organic loading rate on methane production in a CSTR from physicochemical sludge generated in a poultry slaughterhouse.

    Science.gov (United States)

    López-Escobar, Luis A; Martínez-Hernández, Sergio; Corte-Cano, Grisel; Méndez-Contreras, Juan M

    2014-01-01

    The influence of the increase of the organic loading rate (OLR) on methane production in a continuous stirred-tank reactor (CSTR) from physicochemical sludge generated in a poultry slaughterhouse was evaluated. Total solid (TS) to obtain OLR of 1, 5, 10 and 15 g VS L(-1) day(-1), with hydraulic retention times of 29, 6, 6 and 4, respectively, were conditioned. The results showed a decrease in pH levels and an increase in the theoretical volatile fatty acids (VFA). While the yield of methane production decreased from 0.48 to 0.10 LCH4/g VSremoved, respectively, the OLR-10 managed on average 38% removal of volatile solids (VS) and a yield biogas production of 0.81 Lbiogas g(-1) VSremoved and 1.35 L day(-1). This suggests that the OLR increases in an anaerobic system from physicochemical sludge only inhibits the methanogenic metabolism, because there is still substrate consumption and biogas production.

  3. Patterns of cosmogenic radionuclide production rates in the heliosphere and problems of solar modulation on a long time scale

    Science.gov (United States)

    Ustinova, G. K.

    2016-11-01

    The results of long-term studies of cosmogenic radionuclide production rates along the orbits of 39 chondrites that fell to the Earth between 1959 and 2013 are presented. They constitute a long series of homogeneous data, a statistical smoothing of which demonstrate some general patterns of the distribution and variations of Galactic cosmic rays (GCRs) with energy >100 MeV in the inner (chondrite to the short-term closure of the heliosphere for positively charged particles over 14 months between June 2012 and July 2013 is used as an example to show the high resolution of the method of using cosmogenic radionuclides in meteorites as natural GCR detectors.

  4. Fungi in a changing world: growth rates will be elevated, but spore production may decrease in future climates

    Science.gov (United States)

    Damialis, Athanasios; Mohammad, Aqilah B.; Halley, John M.; Gange, Alan C.

    2015-09-01

    Very little is known about the impact of climate change on fungi and especially on spore production. Fungal spores can be allergenic, thus being important for human health. The aim of this study was to investigate how climate change influences the responsive ability of fungi by simulating differing environmental regimes. Fungal species with high spore allergenic potential and atmospheric abundance were grown and experimentally examined under a variety of temperatures and different nutrient availability. Each represented the average decadal air temperature of the 1980s, 1990s and 2000s in the UK, along with an Intergovernmental Panel on Climate Change (IPCC) climate change scenario for 2100. All tests were run on six fungal species: Alternaria alternata, Aspergillus niger, Botrytis cinerea, Cladosporium cladosporioides, Cladosporium oxysporum and Epicoccum purpurascens. Mycelium growth rate and spore production were examined on each single species and competitive capacity among species combinations in pairs. All fungal species grew faster at higher temperatures, and this was more pronounced for the temperature projection in 2100. Most species grew faster when there was lower nutrient availability. Exceptions were the species with the highest growth rate ( E. purpurascens) and with the highest competition capacity ( A. alternata). Most species (except for E. purpurascens) produced more spores in the richer nutrient medium but fewer as temperature increased. C. cladosporioides was an exception, exponentially increasing its spore production in the temperature of the 2100 scenario. Regarding competitive capacity, no species displayed any significant alterations within the environmental range checked. It is suggested that in future climates, fungi will display dramatic growth responses, with faster mycelium growth and lower spore production, with questions risen on relevant allergen potential.

  5. Determination of the effect of brand and product identification on consumer palatability ratings of ground beef patties.

    Science.gov (United States)

    Wilfong, A K; McKillip, K V; Gonzalez, J M; Houser, T A; Unruh, J A; Boyle, E A E; O'Quinn, T G

    2016-11-01

    The objective of this study was to determine the effect of brand and product identification on consumer palatability ratings of ground beef patties. Six treatments were used in the study: 90/10 Certified Angus Beef (CAB) ground sirloin, 90/10 ground beef, 80/20 CAB ground chuck, 80/20 ground chuck, 80/20 ground beef, and 73/27 CAB ground beef. Ground beef was processed into 151.2-g patties using a patty former with 2 consecutively formed patties assigned to blind consumer testing and the following 2 assigned to informed testing. Following cooking to 74°C, patties were cut into quarters and served to consumers. Consumers ( = 112) evaluated samples in 2 rounds for tenderness, juiciness, flavor liking, texture liking, and overall liking. Each trait was also rated as either acceptable or unacceptable. In the first round of testing, samples were blind evaluated, with no information about the treatments provided to consumers, but in the second round, product type and brand were disclosed prior to sample evaluation. Additionally, texture profile and shear force analyses were performed on patties from each treatment. Few differences were observed for palatability traits during blind consumer testing; however, during informed testing, 90/10 CAB ground sirloin was rated greatest ( consumer informed score - consumer blind score)/consumer blind score) ratings for tenderness (17.4%), juiciness (36.5%), flavor liking (23.3%), texture liking (18.2%), and overall liking (24.7%) due to brand disclosure. Increased ( consumers find differences in eating quality among ground beef treatments; however, when consumers are aware of the brand, fat level, and subprimal blend prior to sampling, these factors have a large impact on consumer eating satisfaction.

  6. UNAVCO Geodetic HIgh-Rate and Real-Time Products and Services: A next generation geodetic network

    Science.gov (United States)

    Mattioli, G. S.; Mencin, D.; Meertens, C. M.; Feaux, K.; Looney, S.

    2012-12-01

    Recent advances in GPS technology and data processing are providing position estimates with centimeter-level precision at high-rate (1 Hz) and low latency (seismic, volcanic, magmatic and tsunami deformation sources, and moreover profoundly transforming rapid event characterization, early warning, as well as hazard mitigation and response. Other scientific and operational applications for high-rate GPS also include glacier and ice sheet motions, tropospheric modeling, and better constraints on the dynamics of space weather. UNAVCO, through community input and the recent Plate Boundary Observatory (PBO) NSF-ARRA Cascadia initiative, has nearly completed the process of upgrading a total of 373 PBO GPS sites to real-time high-rate capability and these streams are now being archived in our data center. In addition, UNAVCO hosted an NSF funded workshop in Boulder, CO on March 26-28, which brought together 70 participants representing a spectrum of research fields with a goal to develop a community plan for the use of real-time GPS data products within the UNAVCO and EarthScope communities. These data products are expected to improve and expand the use of real-time GPS data over the next decade. Additionally, in collaboration with NOAA, 74 of these stations will provide meteorological data in real-time, primarily to support watershed and flood analyses for regional early-warning systems related to NOAA's work with California Department of Water Resources. As part of this upgrade UNAVCO is also exploring making the 75 PBO borehole strainmeter sites, whose data are now collected with a latency of 24 hours, available in SEED format in real-time in the near future, providing an opportunity to combine high-rate surface positioning and strain data together.

  7. Symbiotic Association with Mycoplasma hominis Can Influence Growth Rate, ATP Production, Cytolysis and Inflammatory Response of Trichomonas vaginalis.

    Science.gov (United States)

    Margarita, Valentina; Rappelli, Paola; Dessì, Daniele; Pintus, Gianfranco; Hirt, Robert P; Fiori, Pier L

    2016-01-01

    The symbiosis between the parasitic protist Trichomonas vaginalis and the opportunistic bacterium Mycoplasma hominis is the only one currently described involving two obligate human mucosal symbionts with pathogenic capabilities that can cause independent diseases in the same anatomical site: the lower urogenital tract. Although several aspects of this intriguing microbial partnership have been investigated, many questions on the influence of this symbiosis on the parasite pathobiology still remain unanswered. Here, we examined with in vitro cultures how M. hominis could influence the pathobiology of T. vaginalis by investigating the influence of M. hominis on parasite replication rate, haemolytic activity and ATP production. By comparing isogenic mycoplasma-free T. vaginalis and parasites stably associated with M. hominis we could demonstrate that the latter show a higher replication rate, increased haemolytic activity and are able to produce larger amounts of ATP. In addition, we demonstrated in a T. vaginalis-macrophage co-culture system that M. hominis could modulate an aspect of the innate immuno-response to T. vaginalis infections by influencing the production of nitric oxide (NO) by human macrophages, with the parasite-bacteria symbiosis outcompeting the human cells for the key substrate arginine. These results support a model in which the symbiosis between T. vaginalis and M. hominis influences host-microbes interactions to the benefit of both microbial partners during infections and to the detriment of their host.

  8. Symbiotic Association with Mycoplasma hominis Can Influence Growth Rate, ATP Production, Cytolysis and Inflammatory Response of Trichomonas vaginalis

    Science.gov (United States)

    Margarita, Valentina; Rappelli, Paola; Dessì, Daniele; Pintus, Gianfranco; Hirt, Robert P.; Fiori, Pier L.

    2016-01-01

    The symbiosis between the parasitic protist Trichomonas vaginalis and the opportunistic bacterium Mycoplasma hominis is the only one currently described involving two obligate human mucosal symbionts with pathogenic capabilities that can cause independent diseases in the same anatomical site: the lower urogenital tract. Although several aspects of this intriguing microbial partnership have been investigated, many questions on the influence of this symbiosis on the parasite pathobiology still remain unanswered. Here, we examined with in vitro cultures how M. hominis could influence the pathobiology of T. vaginalis by investigating the influence of M. hominis on parasite replication rate, haemolytic activity and ATP production. By comparing isogenic mycoplasma-free T. vaginalis and parasites stably associated with M. hominis we could demonstrate that the latter show a higher replication rate, increased haemolytic activity and are able to produce larger amounts of ATP. In addition, we demonstrated in a T. vaginalis-macrophage co-culture system that M. hominis could modulate an aspect of the innate immuno-response to T. vaginalis infections by influencing the production of nitric oxide (NO) by human macrophages, with the parasite-bacteria symbiosis outcompeting the human cells for the key substrate arginine. These results support a model in which the symbiosis between T. vaginalis and M. hominis influences host-microbes interactions to the benefit of both microbial partners during infections and to the detriment of their host. PMID:27379081

  9. A kinetic study of egg production, fecal egg output, and the rate of proglottid shedding in Hymenolepis nana.

    Science.gov (United States)

    Kumazawa, H

    1992-06-01

    To estimate the rate of shedding of the proglottids during normal development of Hymenolepis nana in mice, 2 parameters, i.e., egg production and fecal egg output, have been determined. Changes in the number of eggs/proglottid along the length of the worm showed that, not only in vitro but also in vivo, a considerable number of eggs is discharged in situ while the proglottids are still attached to the worm. The in situ egg discharge, however, accounts only for a small fraction of the eggs appearing in the feces, and it can be neglected in the estimation of the shedding of proglottids. In H. nana the larva rotates 90 degrees in the egg during its development. This seems to occur in a short period, quite in concert within each proglottid. The transition point (the proglottid where 50% of the eggs have begun rotating) can be a useful landmark to estimate the rate of proglottid shedding. Egg numbers at the transition points approximate the genuine egg production, because in situ egg discharge mostly occurs only after the proglottids have passed the transition point. The 3 processes, i.e., the rotation of the larva in the egg, the in situ egg discharge, and the shedding of proglottids, usually occur in an orderly way. However, on day 20 of infection, just before the worms are lost (or destrobilated), shedding of proglottids seems to be inhibited, whereas the other processes are apparently normal.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Gas exchange rates, plant height, yield components, and productivity of upland rice as affected by plant regulators

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Félix Alvarez

    2012-10-01

    Full Text Available The objective of this work was to evaluate gas exchange rates, plant height, yield components, and productivity of upland rice, as affected by type and application time of plant growth regulators. A randomized block design, in a 4x2 factorial arrangement, with four replicates was used. Treatments consisted of three growth regulators (mepiquat chloride, trinexapac-ethyl, and paclobutrazol, besides a control treatment applied at two different phenological stages: early tillering or panicle primordial differentiation. The experiment was performed under sprinkler-irrigated field conditions. Net CO2 assimilation, stomatal conductance, plant transpiration, and water-use efficiency were measured four times in Primavera upland rice cultivar, between booting and milky grain phenophases. Gas exchange rates were neither influenced by growth regulators nor by application time. There was, however, interaction between these factors on the other variables. Application of trinexapac-ethyl at both tillering and differentiation stages reduced plant height and negatively affected yield components and rice productivity. However, paclobutrazol and mepiquat chloride applied at tillering, reduced plant height without affecting rice yield. Mepiquat chloride acted as a growth stimulator when applied at the differentiation stage, and significantly increased plant height, panicle number, and grain yield of upland rice.

  11. Biogas production from chicken manure at different organic loading rates in a mesophilic-thermopilic two stage anaerobic system.

    Science.gov (United States)

    Dalkılıc, Kenan; Ugurlu, Aysenur

    2015-09-01

    This study investigates the biogas production from chicken manure at different organic loading rates (OLRs), in a mesophilic-thermophilic two stage anaerobic system. The system was operated on semi continuous mode under different OLRs [1.9 g volatile solids (VS)/L·d - 4.7 g VS/L·d] and total solid (TS) contents (3.0-8.25%). It was observed that the anaerobic bacteria acclimatized to high total ammonia nitrogen concentration (>3000 mg/L) originated as a result of the degradation of chicken manure. High volatile fatty acid concentrations were tolerated by the system due to high pH in the reactors. The maximum average biogas production rate was found as 554 mL/g VSfeed while feeding 2.2 g VS/L-d (2.3% VS - 3.8% TS) to the system. Average methane content of produced biogas was 74% during the study.

  12. Polar coralline algal CaCO3-production rates correspond to intensity and duration of the solar radiation

    Science.gov (United States)

    Teichert, S.; Freiwald, A.

    2014-02-01

    In this study we present a comparative quantification of CaCO3 production rates by rhodolith-forming coralline red algal communities situated in high polar latitudes and assess which environmental parameters control these production rates. The present rhodoliths act as ecosystem engineers, and their carbonate skeletons provide an important ecological niche to a variety of benthic organisms. The settings are distributed along the coasts of the Svalbard archipelago, being Floskjeret (78°18' N) in Isfjorden, Krossfjorden (79°08' N) at the eastern coast of Haakon VII Land, Mosselbukta (79°53' N) at the eastern coast of Mosselhalvøya, and Nordkappbukta (80°31' N) at the northern coast of Nordaustlandet. All sites feature Arctic climate and strong seasonality. The algal CaCO3 production rates were calculated from fuchsine-stained, presumably annual growth increments exhibited by the rhodoliths and range from 100.9 g (CaCO3) m-2 yr-1 at Nordkappbukta to 200.3 g (CaCO3) m-2 yr-1 at Floskjeret. The rates correlate to various environmental parameters with geographical latitude being the most significant (negative correlation, R2 = 0.95, p = 0.0070), followed by the duration of the polar night (negative correlation, R2 = 0.93, p = 0.0220), the duration of the sea ice cover (negative correlation, R2 = 0.87, p = 0.0657), and the annual mean temperature (positive correlation, R2 = 0.48, p = 0.0301). This points out sufficient light incidence to be the main control of the growth of the examined coralline red algal rhodolith communities, while temperature is less important. Thus, the ongoing global change with its rising temperatures will most likely result in impaired conditions for the algae, because the concomitant increased global runoff will decrease water transparency and hence light incidence at the four offshore sites. Regarding the aforementioned role of the rhodoliths as ecosystem engineers, the impact on the associated organisms will presumably also be negative.

  13. Rectal temperatures, respiratory rates, production, and reproduction performances of crossbred Girolando cows under heat stress in northeastern Brazil

    Science.gov (United States)

    da Costa, Antônio Nélson Lima; Feitosa, José Valmir; Montezuma, Péricles Afonso; de Souza, Priscila Teixeira; de Araújo, Airton Alencar

    2015-11-01

    This study compared the two breed groups of Girolando (½ Holstein ½ Gyr vs. ¾ Holstein ¼ Gyr) through analysis of the percentages (stressed or non-stressed cows) of rectal temperature (RT), respiratory rate (RR) and pregnancy rate (PR), and means of production and reproduction parameters to determine the group best suited to rearing in semiarid tropical climate. The experiment was conducted at the farm, in the municipality of Umirim, State of Ceará, Brazil. Two hundred and forty cows were used in a 2 × 2 factorial study; 120 of each group were kept under an intensive system during wet and dry seasons. The environmental parameters obtained were relative humidity (RH), air temperature (AT), and the temperature and humidity index (THI). Pregnancy diagnosis (PD) was determined by ultrasonography 30 days after artificial insemination (AI). The milk production of each cow was recorded with automated milkings in the farm. The variables were expressed as mean and standard error, evaluated by ANOVA at 5 % probability using the GLM procedure of SAS. Chi-square test at 5 % probability was applied to data of RT, RR, pregnancy rate (PR), and the number of AIs to obtain pregnancy. The majority of ½ Holstein cows showed mean values of RT and RR within the normal range in both periods and shifts. Most animals of the ¾ Holstein group exhibited the RR means above normal during the afternoon in the rainy and dry periods and RT means above normal during the afternoon in the dry period. After analyses, ½ Holstein crossbred cows are more capable of thermoregulating than ¾ Holstein cows under conditions of thermal stress, and the dry period was more impacting for bovine physiology with significant changes in physiological parameters, even for the first breed group. Knowledge of breed groups adapted to climatic conditions of northeastern Brazil can directly assist cattle farmers in selecting animals best adapted for forming herds.

  14. A new clinical rating scale for work absence and productivity: validation in patients with major depressive disorder

    Directory of Open Access Journals (Sweden)

    Yatham Lakshmi N

    2009-12-01

    Full Text Available Abstract Background The prevalence of major depressive disorder (MDD is highest in working age people and depression causes significant impairment in occupational functioning. Work productivity and work absence should be incorporated into clinical assessments but currently available scales may not be optimized for clinical use. This study seeks to validate the Lam Employment Absence and Productivity Scale (LEAPS, a 10-item self-report questionnaire that takes 3-5 minutes to complete. Methods The study sample consisted of consecutive patients attending a Mood Disorders outpatient clinic who were in full- or part-time paid work. All patients met DSM-IV criteria for MDD and completed during their intake assessment the LEAPS, the self-rated version of the Quick Inventory for Depressive Symptomatology (QIDS-SR, the Sheehan Disability Scale (SDS and the Health and Work Performance Questionnaire (HPQ. Standard psychometric analyses for validation were conducted. Results A total of 234 patients with MDD completed the assessments. The LEAPS displayed excellent internal consistency as assessed by Cronbach's alpha of 0.89. External validity was assessed by comparing the LEAPS to the other clinical and work functioning scales. The LEAPS total score was significantly correlated with the SDS work disability score (r = 0.63, p Conclusion The LEAPS displays good internal and external validity in a population of patients with MDD attending an outpatient clinic, which suggests that it may be a clinically useful tool to assess and monitor work functioning and productivity in depressed patients.

  15. Growth rates and milk production potential of Sahelian and Red Sokoto breeds of goats in northern Guinea Savannah.

    Science.gov (United States)

    Makun, H J; Ajanusi, J O; Ehoche, O W; Lakpini, C A M; Otaru, S M

    2008-02-15

    The milk production potentials and growth rates of Red Sokoto and Sahelian goats fed basal diets of maize stover and Digitaria smutsii (wolly finger grass) supplemented with concentrate was investigated in two separate trials. In experiment 1, ten multi-parous does were allocated to intensive management following kidding. Does were hand-milked twice weekly and the milk production recorded. Body weight changes of dam and kid, milk fat, milk solid were determined weekly over 12 weeks period. The average birth weight of the Sahelian (2.2+/-0.23 kg) was significantly (p0.05) in daily milk yield and total lactation between the two breeds. The total solids and milk fat of 16.4+/-0.39 and 3.7+/-0.13% were significantly (pgoats. Animals were group-fed based on sex and fed Digitaria smutsii hay supplemented with concentrate. The growth trial lasted for 150 days with a 14 day digestibility trial. The Average Daily Gain (ADG) were significantly (pgoat can adapted and fit into the production systems of Sudan Savannah rural farmers.

  16. On the fundamental equation of nonequilibrium statistical physics—Nonequilibrium entropy evolution equation and the formula for entropy production rate

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper the author presents an overview on his own research works. More than ten years ago, we proposed a new fundamental equation of nonequilibrium statistical physics in place of the present Liouville equation. That is the stochastic velocity type’s Langevin equation in 6N dimensional phase space or its equivalent Liouville diffusion equation. This equation is time-reversed asymmetrical. It shows that the form of motion of particles in statistical thermodynamic systems has the drift-diffusion duality, and the law of motion of statistical thermodynamics is expressed by a superposition of both the law of dynamics and the stochastic velocity and possesses both determinism and probability. Hence it is different from the law of motion of particles in dynamical systems. The stochastic diffusion motion of the particles is the microscopic origin of macroscopic irreversibility. Starting from this fundamental equation the BBGKY diffusion equation hierarchy, the Boltzmann collision diffusion equation, the hydrodynamic equations such as the mass drift-diffusion equation, the Navier-Stokes equation and the thermal conductivity equation have been derived and presented here. What is more important, we first constructed a nonlinear evolution equation of nonequilibrium entropy density in 6N, 6 and 3 dimensional phase space, predicted the existence of entropy diffusion. This entropy evolution equation plays a leading role in nonequilibrium entropy theory, it reveals that the time rate of change of nonequilibrium entropy density originates together from its drift, diffusion and production in space. From this evolution equation, we presented a formula for entropy production rate (i.e. the law of entropy increase) in 6N and 6 dimensional phase space, proved that internal attractive force in nonequilibrium system can result in entropy decrease while internal repulsive force leads to another entropy increase, and derived a common expression for this entropy decrease rate or

  17. Fed-batch alcoholic fermentation of sugar cane blackstrap molasses: Influence of the feeding rate on yeast yield and productivity

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, J.C.M. de; Aquarone, E.; Sato, S.; Brazzach, M.L.; Moraes, D.A. (Faculdade de Ciencias Farmaceuticas, Sao Paulo Univ., SP (Brazil)); Borzani, W. (Centro de Desenvolvimento Biotecnologico, Joinville, SC (Brazil))

    1993-02-01

    Fed-batch ethanol fermentation tests of sugar cane blackstrap molasses were carried out at 32deg C and pH 4.5-5.0, using pressed yeast as inoculum, and with no air supply. Two values of the fermentor filling-up time were adopted: 5 h and 7 h. The feeding rates obeyed equation F=F[sub 0].e[sup K.t], with K equal to 0.0, 0.2, 0.4, 0.6 and 0.8 h[sup -1]. The average yeast yields and the average yeast productivities increased up to 33% and 45%, respectively, while the ethanol yield (average=76%; standard deviation=4%) was practically unaffected when K increased from 0 to 0.8 h[sup -1]. (orig.).

  18. Application of a packed bed reactor for the production of hydrogen from cheese whey permeate: effect of organic loading rate.

    Science.gov (United States)

    Fernández, Camino; Carracedo, Begoña; Martínez, Elia Judith; Gómez, Xiomar; Morán, Antonio

    2014-01-01

    The production of H2 was studied using a packed bed reactor with polyurethane foam acting as support material. Experiments were performed using mixed microflora under non sterile conditions. The system was initially operated with synthetic wastewater as the sole substrate. Subsequently, cheese whey permeate was added to the system at varying organic loading rates (OLR). The performance of the reactor was evaluated by applying a continuous decrease in OLR. As a result, a significant decrease in H2 yields (HY) was observed with the decrease in OLR from 18.8 to 6.3 g chemical oxygen demand (COD)/L d. Microbial analysis demonstrated that the prevalence of non-hydrogen producers, Sporolactobacillus sp. and Prevotella, was the main reason for low HYs obtained. This behavior indicates that the fermentation under non-sterile conditions was favored by high concentrations of substrate by creating an adverse environment for nonhydrogen producer organisms.

  19. Clinically relevant HOCl concentrations reduce clot retraction rate via the inhibition of energy production in platelet mitochondria.

    Science.gov (United States)

    Misztal, T; Rusak, T; Tomasiak, M

    2014-12-01

    Using porcine blood, we examined the impact of hypochlorite, product of activated inflammatory cells, on clot retraction (CR), an important step of hemostasis. We found that, in vitro, HOCl is able to reduce CR rate and enlarge final clot size in whole blood (t.c. 100 μM), platelet-rich plasma (PRP) threshold concentration (t.c. 50 μM), and an artificial system (washed platelets and fibrinogen) (t.c. 25 nM). Combination of low HOCl and peroxynitrite concentrations resulted in synergistic inhibition of CR by these stressors. Concentrations of HOCl completely inhibiting CR failed to affect the kinetics of coagulation measured in PRP and in platelet-free plasma. Concentrations of HOCl reducing CR rate in PRP augmented production of lactate, inhibited consumption of oxygen by platelets, and decreased total adenosine triphosphate (ATP) content in PRP-derived clots. In an artificial system, concentrations of HOCl resulting in inhibition of CR (25-100 nM) reduced mitochondrial transmembrane potential and did not affect actin polymerization in thrombin-stimulated platelets. These concentrations of HOCl failed to affect the adhesion of washed platelets to fibrinogen and to evoke sustained calcium signal, thus excluding stressor action on glycoprotein IIb/IIIa receptors. Exogenously added Mg-ATP almost completely recovered HOCl-mediated retardation of CR. Concentrations of HOCl higher than those affecting CR reduced thromboelastometric variables (maximum clot firmness and α angle). We conclude that low clinically relevant HOCl concentrations may evoke the inhibition of CR via the reduction of platelet contractility resulted from malfunction of platelet mitochondria. At the inflammatory conditions, CR may be the predominant HOCl target.

  20. Optical crop sensor for variable-rate nitrogen fertilization in corn: i - plant nutrition and dry matter production

    Directory of Open Access Journals (Sweden)

    Jardes Bragagnolo

    2013-10-01

    Full Text Available Variable-rate nitrogen fertilization (VRF based on optical spectrometry sensors of crops is a technological innovation capable of improving the nutrient use efficiency (NUE and mitigate environmental impacts. However, studies addressing fertilization based on crop sensors are still scarce in Brazilian agriculture. This study aims to evaluate the efficiency of an optical crop sensor to assess the nutritional status of corn and compare VRF with the standard strategy of traditional single-rate N fertilization (TSF used by farmers. With this purpose, three experiments were conducted at different locations in Southern Brazil, in the growing seasons 2008/09 and 2010/11. The following crop properties were evaluated: above-ground dry matter production, nitrogen (N content, N uptake, relative chlorophyll content (SPAD reading, and a vegetation index measured by the optical sensor N-Sensor® ALS. The plants were evaluated in the stages V4, V6, V8, V10, V12 and at corn flowering. The experiments had a completely randomized design at three different sites that were analyzed separately. The vegetation index was directly related to above-ground dry matter production (R² = 0.91; p<0.0001, total N uptake (R² = 0.87; p<0.0001 and SPAD reading (R² = 0.63; p<0.0001 and inversely related to plant N content (R² = 0.53; p<0.0001. The efficiency of VRF for plant nutrition was influenced by the specific climatic conditions of each site. Therefore, the efficiency of the VRF strategy was similar to that of the standard farmer fertilizer strategy at sites 1 and 2. However, at site 3 where the climatic conditions were favorable for corn growth, the use of optical sensors to determine VRF resulted in a 12 % increase in N plant uptake in relation to the standard fertilization, indicating the potential of this technology to improve NUE.

  1. Relationship of efficiency indices with performance, heart rate, oxygen consumption, blood parameters, and estimated heat production in Nellore steers.

    Science.gov (United States)

    Chaves, A S; Nascimento, M L; Tullio, R R; Rosa, A N; Alencar, M M; Lanna, D P

    2015-10-01

    The objective of this study was to examine the relationship of efficiency indices with performance, heart rate, oxygen consumption, blood parameters, and estimated heat production (EHP) in Nellore steers. Eighteen steers were individually lot-fed diets of 2.7 Mcal ME/kg DM for 84 d. Estimated heat production was determined using oxygen pulse (OP) methodology, in which heart rate (HR) was monitored for 4 consecutive days. Oxygen pulse was obtained by simultaneously measuring HR and oxygen consumption during a 10- to 15-min period. Efficiency traits studied were feed efficiency (G:F) and residual feed intake (RFI) obtained by regression of DMI in relation to ADG and midtest metabolic BW (RFI). Alternatively, RFI was also obtained based on equations reported by the NRC's to estimate individual requirement and DMI (RFI calculated by the NRC [1996] equation [RFI]). The slope of the regression equation and its significance was used to evaluate the effect of efficiency indices (RFI, RFI, or G:F) on the traits studied. A mixed model was used considering RFI, RFI, or G:F and pen type as fixed effects and initial age as a covariate. For HR and EHP variables, day was included as a random effect. There was no relationship between efficiency indices and back fat depth measured by ultrasound or daily HR and EHP ( > 0.05). Because G:F is obtained in relation to BW, the slope of G:F was positive and significant ( consumption per beat was not related to G:F; however, it was lower for RFI- and RFI-efficient steers, and consequently, oxygen volume (mL·min·kg) and OP (μL O·beat·kg) were also lower ( 0.05); however, G:F-efficient steers showed lower hematocrit and hemoglobin concentrations ( consumption and OP were detected, indicating that the OP methodology may be useful to predict growth efficiency.

  2. High-Rate Anaerobic Side-Stream Reactor (ASSR) Processes to Minimize the Production of Excess Sludge.

    Science.gov (United States)

    Park, Chul; Chon, Dong-Hyun

    2015-12-01

    High-rate anaerobic side-stream reactor (ASSR) processes were developed to minimize excess sludge production during wastewater treatment. New ASSRs were operated in 2.5-day solids retention time (SRT), much shorter than 10-day SRT used by the commercial sludge reduction process. The 2.5-day was selected based on literature review and preliminary studies, showing that maximum solublization of key floc components, such as divalent cations, extracellular polymeric substances (EPS), and protease, occur within 2 to 3 days of anaerobic digestion. The laboratory reactor study showed that 2.5-day ASSR systems produced approximately 60 and 20% less sludge than the control (no ASSR) and the 10-day ASSR, respectively. The experimental systems showed acceptable effluent quality, despite minimal sludge wastage. This was possible because sludge EPS were continuously released/degraded and regenerated as sludge underwent recirculation between ASSR and the aerobic basin. The results supported that the activated sludge process incorporating small ASSRs significantly decrease the production of excess sludge during wastewater treatment.

  3. High-rate production of functional nanostructured films and devices by coupling flame spray pyrolysis with supersonic expansion.

    Science.gov (United States)

    Wegner, K; Vinati, S; Piseri, P; Antonini, A; Zelioli, A; Barborini, E; Ducati, C; Milani, P

    2012-05-11

    The fabrication of functional thin films and devices by direct deposition of nanoparticles from the gas phase is a promising approach enabling, for instance, the integration of complex analytical and sensing capabilities on microfabricated platforms. Aerosol-based techniques ensure large-scale nanoparticle production and they are potentially suited for this goal. However, they are not adequate in terms of fine control over the lateral resolution of the coatings, mild processing conditions (avoiding high temperature and aggressive chemicals), low contamination and compatibility with microfabrication processes. Here we report the high-rate and efficient production of functional nanostructured films by nanoparticle assembling obtained by the combination of flame spray pyrolysis and supersonic expansion. Our approach merges the advantages of flame spray pyrolysis for bulk nanopowders such as process stability and wide material library availability with those of supersonic cluster beam deposition in terms of lateral resolution and of direct integration of nanomaterials on devices. We efficiently produced nanostructured films and devices (such as gas sensors) using metal oxide, pure noble metal and oxide-supported noble metal nanoparticles.

  4. Organic loading rate impact on biohydrogen production and microbial communities at anaerobic fluidized thermophilic bed reactors treating sugarcane stillage.

    Science.gov (United States)

    Santos, Samantha Christine; Rosa, Paula Rúbia Ferreira; Sakamoto, Isabel Kimiko; Varesche, Maria Bernadete Amâncio; Silva, Edson Luiz

    2014-05-01

    This study aimed to evaluate the effect of high organic loading rates (OLR) (60.0-480.00 kg COD m(-3)d(-1)) on biohydrogen production at 55°C, from sugarcane stillage for 15,000 and 20,000 mg CODL(-1), in two anaerobic fluidized bed reactors (AFBR1 and AFBR2). It was obtained, for H2 yield and content, a decreasing trend by increasing the OLR. The maximum H2 yield was observed in AFBR1 (2.23 mmol g COD added(-1)). The volumetric H2 production was proportionally related to the applied hydraulic retention time (HRT) of 6, 4, 2 and 1h and verified in AFBR1 the highest value (1.49 L H2 h(-1)L(-1)). Among the organic acids obtained, there was a predominance of lactic acid (7.5-22.5%) and butyric acid (9.4-23.8%). The microbial population was set with hydrogen-producing fermenters (Megasphaera sp.) and other organisms (Lactobacillus sp.).

  5. Induction of traps by Ostertagia ostertagi larvae, chlamydospore production and growth rate in the nematode-trapping fungus Duddingtonia flagrans

    DEFF Research Database (Denmark)

    Grønvold, J.; Nansen, P.; Henriksen, S. A.;

    1996-01-01

    Biological control of parasitic nematodes of domestic animals can be achieved by feeding host animals chlamydospores of the nematode-trapping fungus Duddingtonia flagrans. In the host faeces, D. flagrans develop traps that may catch nematode larvae. In experiments on agar, D. flagrans had a growth...... 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....... 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...

  6. Late Cenozoic tephrostratigraphy offshore the southern Central American Volcanic Arc: 2. Implications for magma production rates and subduction erosion

    Science.gov (United States)

    Schindlbeck, J. C.; Kutterolf, S.; Freundt, A.; Straub, S. M.; Vannucchi, P.; Alvarado, G. E.

    2016-11-01

    Pacific drill sites offshore Central America provide the unique opportunity to study the evolution of large explosive volcanism and the geotectonic evolution of the continental margin back into the Neogene. The temporal distribution of tephra layers established by tephrochonostratigraphy in Part 1 indicates a nearly continuous highly explosive eruption record for the Costa Rican and the Nicaraguan volcanic arc within the last 8 Myr. The widely distributed marine tephra layers comprise the major fraction of the respective erupted tephra volumes and masses thus providing insights into regional and temporal variations of large-magnitude explosive eruptions along the southern Central American Volcanic Arc (CAVA). We observe three pulses of enhanced explosive volcanism between 0 and 1 Ma at the Cordillera Central, between 1 and 2 Ma at the Guanacaste and at >3 Ma at the Western Nicaragua segments. Averaged over the long-term the minimum erupted magma flux (per unit arc length) is ˜0.017 g/ms. Tephra ages, constrained by Ar-Ar dating and by correlation with dated terrestrial tephras, yield time-variable accumulation rates of the intercalated pelagic sediments with four prominent phases of peak sedimentation rates that relate to tectonic processes of subduction erosion. The peak rate at >2.3 Ma near Osa particularly relates to initial Cocos Ridge subduction which began at 2.91 ± 0.23 Ma as inferred by the 1.5 Myr delayed appearance of the OIB geochemical signal in tephras from Barva volcano at 1.42 Ma. Subsequent tectonic re-arrangements probably involved crustal extension on the Guanacaste segment that favored the 2-1 Ma period of unusually massive rhyolite production.

  7. EFFECT OF GROWTH STAGES AND RANGE SYSTEMS ON VEGETATION ATTRIBUTES, CARRYING CAPACITY, STOCKING RATE AND FORAGE PRODUCTIVITY, NORTH KORDOFAN, SUDAN

    Directory of Open Access Journals (Sweden)

    Abdel Moniem M.A. El hag

    2012-03-01

    Full Text Available The range vegetation attributes, carrying capacity, stocking rates and forage productivity were studied in close and open range systems at the flowering and seed setting stages during the September and November 2010, respectively, in El Rosa (El-khuwei locality. Sampling was done by locating 2Km2 in close and open range systems in a radiating manner from the centre of each site. Completely Randomized Design (CRD was used to analyses treatments. Biomass production of plants and plant cover at the flowering stage in the close range system were significantly (P<0.0001 higher than that at the seed setting stage in the open range system. The plant density was significant (P<0.05 higher in the close rang system at the flowering stage and lower at the seed setting stage in the open range system. Bare soil and litter was significantly higher (P<0.0001 in the open range system during the seed setting stage and lower in the close range system during the flowering stage. Forage productivity of plants and shrubs browse kg/ha on rangeland was significantly higher (P<0.05 in the close range system during the flowering stage and lower in open range system at the seed setting stage. Carrying capacity was significantly higher (P<0.0001 in the close range system at the seed setting stage and lower in the open range at the flowering stage. Stoking rates in open range system during the seed setting stage was significantly higher (P<0.0001 and lower in the close range system during the seed setting stage. The frequencies of Huskneet (Cenchrus biflorus, Bano, (Eragrostis tremula, Difra (Echinocloa colonum, leflef Luffa aegyptiaca, Gaw (Aristida sp, Shuleny Zornia glochidiata and Aborakhus Andropogon gayanus were higher in close system during the two stages of growth. Plants such as Abodaib Ceraotheca sesamoid, Bigual Blepharis linarifolia, Tmrfar (Oldenlandia senegalensis, Rabaa (Zalea sp, Himeira Hymerocardia, Diresa (Tribulus terrestris and Huntot Merremia pinnata

  8. Relationship between tissue plasminogen activator production and specific growth rate in Chinese hamster ovary cells cultured in mannose at low temperature.

    Science.gov (United States)

    Berrios, Julio; Díaz-Barrera, Alvaro; Bazán, Consuelo; Altamirano, Claudia

    2009-10-01

    Chinese hamster ovary (CHO) cells, producing human recombinant tissue plasminogen activator (tPA), were grown with mannose (5, 20 and 40 mM) instead of glucose at 31, 33 and 37 degrees C. The highest tPA concentration (1.5 mg l(-1) at 144 h of cultivation) and tPA specific production rate (47 ng 10(-6) cell h(-1)) were obtained at 31 degrees C and 40 mM mannose. Regardless of the temperature or mannose concentration used, an inverse relationship between the specific growth rate and tPA specific production rate was observed, suggesting that tPA production rate would be directly controlled by the growth rate.

  9. Hydraulic conductance as well as nitrogen accumulation plays a role in the higher rate of leaf photosynthesis of the most productive variety of rice in Japan

    OpenAIRE

    2011-01-01

    An indica variety Takanari is known as one of the most productive rice varieties in Japan and consistently produces 20–30% heavier dry matter during ripening than Japanese commercial varieties in the field. The higher rate of photosynthesis of individual leaves during ripening has been recognized in Takanari. By using pot-grown plants under conditions of minimal mutual shading, it was confirmed that the higher rate of leaf photosynthesis is responsible for the higher dry matter production aft...

  10. Effect of dilution rate and methanol-glycerol mixed feeding on heterologous Rhizopus oryzae lipase production with Pichia pastoris Mut(+) phenotype in continuous culture.

    Science.gov (United States)

    Canales, Christian; Altamirano, Claudia; Berrios, Julio

    2015-01-01

    The induction using substrate mixtures is an operational strategy for improving the productivity of heterologous protein production with Pichia pastoris. Glycerol as a cosubstrate allows for growth at a higher specific growth rate, but also has been reported to be repressor of the expression from the AOX1 promoter. Thus, further insights about the effects of glycerol are required for designing the induction stage with mixed substrates. The production of Rhizopus oryzae lipase (ROL) was used as a model system to investigate the application of methanol-glycerol feeding mixtures in fast metabolizing methanol phenotype. Cultures were performed in a simple chemostat system and the response surface methodology was used for the evaluation of both dilution rate and methanol-glycerol feeding composition as experimental factors. Our results indicate that productivity and yield of ROL are strongly affected by dilution rate, with no interaction effect between the involved factors. Productivity showed the highest value around 0.04-0.06 h(-1) , while ROL yield decreased along the whole dilution rate range evaluated (0.03-0.1 h(-1) ). Compared to production level achieved with methanol-only feeding, the highest specific productivity was similar in mixed feeding (0.9 UA g-biomass(-1) h(-1) ), but volumetric productivity was 70% higher. Kinetic analysis showed that these results are explained by the effects of dilution rate on specific methanol uptake rate, instead of a repressor effect caused by glycerol feeding. It is concluded that despite the effect of dilution rate on ROL yield, mixed feeding strategy is a proper process option to be applied to P. pastoris Mut(+) phenotype for heterologous protein production.

  11. Decentralized scheduling algorithm to improve the rate of production without increasing the stocks of intermediates; Zaiko wo fuyasu kotonaku seisan sokudo wo kojo saseru jiritsu bunsangata sukejuringu arugorizumu

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kazuhiro; Shiigi, Daisuke; Tsuge, Yoshifumi; Matsuyama, Hisayoshi [Kyushu University, Fukuoka (Japan). Department of Chemical Engineering

    1999-03-10

    In a factory with a multi-stage production system, push-type scheduling methods can hardly improve the production rate without increasing the stocks of intermediates. For products whose specifications are known before their orders, a pull-type scheduling method named Kanban system has been developed, and has succeeded to improve the production rate without increasing the stocks of intermediates. The Kanban system, however, is not applicable to custom-made products whose specifications are not known before their orders. In this paper, a 'Virtual Kanban (VK) system' is presented as a pull-type scheduling method which is applicable to custom-made products, and its usefulness is demonstrated by simulation of an application specific integrated circuit manufacturing facility. (author)

  12. Benefits of chemical fibre industry down evidently in the first half of 2008 Industrial production growth rate dropped slightly, imports decreased evidently while exports grew steadily

    Institute of Scientific and Technical Information of China (English)

    Gracie; Guo

    2008-01-01

    Production From January to May, China’s chemical fiber production rose 7.4 percent from a year earlier to 10.04 million tons, but that was 10.49 percentage points less than the growth rate during the same five- month period last year,the China National Textile and Apparel

  13. The coffee diterpene cafestol increases plasma triacylglycerol by increasing the production rate of large VLDL apolipoprotein B in healthy normolipidemic subjects

    NARCIS (Netherlands)

    Roos, de B.; Caslake, M.J.; Stalenhoef, A.F.H.; Bedford, D.; Demacker, P.N.; Katan, M.B.; Packard, C.J.

    2001-01-01

    Background: Cafestol is a diterpene in unfiltered coffee that raises plasma triacylglycerol in humans. Objective: We studied whether cafestol increases plasma triacylglycerol by increasing the production rate or by decreasing the fractional catabolic rate of VLDL1 [Svedberg flotation unit (Sf) 60-40

  14. AISI/DOE Technology Roadmap Program: A Technology of Low Coal Rate and High Productivity of RHF Ironmaking

    Energy Technology Data Exchange (ETDEWEB)

    Wei-Kao Lu

    2002-09-15

    An economical and environment-friendly ironmaking process based on heating the chemiexecy self-sufficient green balls of iron ore and coal in a hearth furnace is being developed with financial support from AISI members and DOE. DRI, which is hot (1400 C), dense (3.2 g/cm) and of high degree of metallization (95%), has been produced in laboratory and in a pilot plant in Genoa, Italy. Products of such quality have been made from American and Brazilian ores, BOF sludge, EAF dust/BOF sludge mixtures and millscale. The removal of zinc and lead from green balls by this process is essentially complete. In comparison with typical blast furnace operation, the new technology with a melter would have a lower total coal rate by 200kg.THM. The elimination of cokemaking and high temperature agglomeration steps, and a simpler gas handling system would lead to lower capital and operating costs. In comparison with commercial RHF practice it is different in atmosphere (fully oxidized at 1600 to 1650 C), in bed height (120 mm instead of 20-25 mm) and in pellet composition (much less coal but of higher VM). The combined effect leads to three times higher furnace productivity, lower coal consumption and superior DRI quality. The risk of re-oxidation (slag formation) and dusty operation are practiexecy eliminated. The process is stable, tolerant and independent of the size, shape and movement of the hearth. However, materials handling (e.g., discharge of hot DRI) and the exact energy savings have to be established in a larger furnace, straight or rotary, and in a continuous mode of operation.

  15. Deuterium isotope effects on toluene metabolism. Product release as a rate-limiting step in cytochrome P-450 catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Ling, K.H.; Hanzlik, R.P.

    1989-04-28

    Liver microsomes from phenobarbital-induced rats oxidize toluene to a mixture of benzyl alcohol plus o-, m- and p-cresol (ca. 69:31). Stepwise deuteration of the methyl group causes stepwise decreases in the yield of benzyl alcohol relative to cresols (ca. 24:76 for toluene-d3). For benzyl alcohol formation from toluene-d3 DV = 1.92 and D(V/K) = 3.53. Surprisingly, however, stepwise deuteration induces stepwise increases in total oxidation, giving rise to an inverse isotope effect overall (DV = 0.67 for toluene-d3). Throughout the series (i.e. d0, d1, d2, d3) the ratios of cresol isomers remain constant. These results are interpreted in terms of product release for benzyl alcohol being slower than release of cresols (or their epoxide precursors), and slow enough to be partially rate-limiting in turnover. Thus metabolic switching to cresol formation causes a net acceleration of turnover.

  16. Volatile elements production rates in a 1.4 Gev proton-irradiated molten lead-bismuth target

    CERN Document Server

    Zanini, L; Everaerts, P; Fallot, M; Franberg, H; Gröschel, F; Jost, C; Kirchner, T; Kojima, Y; Köster, U; Lebenhaft, J; Manfrina, E; Pitcher, E J; Ravn, H L; Tall, Y; Wagner, W; Wohlmuther, M

    2005-01-01

    Production rates of volatile elements following spallation reaction of 1.4 GeV protons on a liquid Pb/Bi target have been measured. The experiment was performed at the ISOLDE facility at CERN. These data are of interest for the developments of targets for accelerator driven systems such as MEGAPIE. Additional data have been taken on a liquid Pb target. Calculations were performed using the FLUKA and MCNPX Monte Carlo codes coupled with the evolution codes ORIHET3 and FISPACT using different options for the intra-nuclear cascades and evaporation models. Preliminary results from the data analysis show good comparison with calculations for Hg and for noble gases. For other elements such as I it is apparent that only a fraction of the produced isotopes is released. The agreement with the experimental data varies depending on the model combination used. The best results are obtained using MCNPX with the INCL4/ABLA models and with FLUKA. Discrepancies are found for some isotopes produced by fission using the MCNPX ...

  17. A simple model for reconstructing geomagnetic field intensity with (10)~Be production rate and its application in Loess studies

    Institute of Scientific and Technical Information of China (English)

    J.; Warren; BECK

    2008-01-01

    A simple model for reconstructing the paleomagnetic field intensity with (10)~Be production rate was used for the first time in Loess (10)~Be studies of Luochuan profile. Using the LGM (Last Glacial Maxmium) method, the climatic effects and geomagnetic modulation effects on loess (10)~Be was separated and in turn the 80 ka geomagnetic excursion sequence reconstructed, of which the globally remarkable geomagnetic excursion events such as the Laschamp (42 ka), Mono Lake (32 ka) during the Last Glacial period were revealed and the paleo-geomagnetic intensity curve from Loess (10)~Be over the past 80 ka was quantitatively reconstructed. The reconstructed paleo-intensity fits well with the paleo-intensity curves (SINT200 and NAPIS75), which indicates the significance of global criterion of the (10)~Be paleo- intensity curve and the future direction of loess (10)~Be tracing studies. Results show the irregular vari-ability of the East Asian monsoon precipitation in Loess Plateau is the main cause that has resulted in the ambiguity of the geomagnetic modulation of the (10)~Be record in the loess, and the intrinsic source component of the loess (10)~Be and inherited fraction of magnetic susceptibility (SUS) are characterized by the "quasi-homogeneous distribution" manner.

  18. A simple model for reconstructing geomasnetic field intensity with 10Be production rate and its application in Loess studies

    Institute of Scientific and Technical Information of China (English)

    XIAN Feng; AN ZhiSheng; WU ZhenKun; J.Warren BECK; YU HuaGui; KANG ZhiHai; CHENG Peng

    2008-01-01

    A simple model for reconstructing the paleomagnetic field intensity with 10Be production rate was used for the first time in Loess 10Be studies of Luochuan profile. Using the LGM (Last Glacial Maxmium) method, the climatic effects and geomagnetic modulation effects on loess 10Be was separated and in turn the 80 ka geomagnetic excursion sequence reconstructed, of which the globally remarkable geomagnetic excursion events such as the Laschamp (42 ka), Mono Lake (32 ka) during the Last Glacial period were revealed and the paleo-geomagnetic intensity curve from Loess 10Be over the past 80 ka was quantitatively reconstructed. The reconstructed paleo-intensity fits well with the paleo-intensity curves (SINT200 and NAPIS75), which indicates the significance of global criterion of the 10Be paleo-intensity curve and the future direction of loess 10Be tracing studies. Results show the irregular vari-ability of the East Asian monsoon precipitation in Loess Plateau is the main cause that has resulted in the ambiguity of the geomagnetic modulation of the 10Be record in the loess, and the intrinsic source component of the loess 10Be and inherited fraction of magnetic susceptibility (SUS) are characterized by the "quasi-homogeneous distribution" manner.

  19. Deoxyxylulose 5-phosphate reductoisomerase is not a rate-determining enzyme for essential oil production in spike lavender.

    Science.gov (United States)

    Mendoza-Poudereux, Isabel; Muñoz-Bertomeu, Jesús; Arrillaga, Isabel; Segura, Juan

    2014-11-01

    Spike lavender (Lavandula latifolia) is an economically important aromatic plant producing essential oils, whose components (mostly monoterpenes) are mainly synthesized through the plastidial methylerythritol 4-phosphate (MEP) pathway. 1-Deoxy-D-xylulose-5-phosphate (DXP) synthase (DXS), that catalyzes the first step of the MEP pathway, plays a crucial role in monoterpene precursors biosynthesis in spike lavender. To date, however, it is not known whether the DXP reductoisomerase (DXR), that catalyzes the conversion of DXP into MEP, is also a rate-limiting enzyme for the biosynthesis of monoterpenes in spike lavender. To investigate it, we generated transgenic spike lavender plants constitutively expressing the Arabidopsis thaliana DXR gene. Although two out of the seven transgenic T0 plants analyzed accumulated more essential oils than the controls, this is hardly imputable to the DXR transgene effect since a clear correlation between transcript accumulation and monoterpene production could not be established. Furthermore, these increased essential oil phenotypes were not maintained in their respective T1 progenies. Similar results were obtained when total chlorophyll and carotenoid content in both T0 transgenic plants and their progenies were analyzed. Our results then demonstrate that DXR enzyme does not play a crucial role in the synthesis of plastidial monoterpene precursors, suggesting that the control flux of the MEP pathway in spike lavender is primarily exerted by the DXS enzyme.

  20. Toxicology of drinking water disinfection byproducts from nutrients. Rate studies of destruction of polyunsaturated fatty acids in vitro by chlorine-based disinfectants.

    Science.gov (United States)

    Bercz, J P

    1992-01-01

    As model reactions between unsaturated fats and water disinfectants in the GI tract, relative rates of destruction of seven polyunsaturated fatty acids (L, alpha Ln, gamma Ln, Ara, EPA, DH, and DT) by OCl- and NH2Cl were investigated in vitro. Using millimolar solutions of seven PUFAs combined with various OCl- mole ratios, disappearance of PUFAs was followed by UV spectrophotometry at pH = 9.5 and at 35 degrees C via conjugated hydroperoxydienes at 234 nm. While OCl- rapidly destroyed all PUFAs, NH2Cl was inert. Overall second-order rate constants computed for L at increasing times disclosed that the attack on the cis-CH=CHCH2CH=CH moiety by OCl- does not follow simple second-order kinetics. Using a logit-log transform and second-order polynomial regression analysis of L's disappearance in a stoichiometric ([L] = 1.2 mM; [ClO-] = 2.4 mM) mix, data were analyzed by the time ratio method of Schwemer and Frost. These agreed with a sequential system of at least two irreversible second-order reactions having k1 = 15.6 L.mol-1.s-1 and k2 = 2.6 L.mol-1.s-1. Preliminary GC/MS analysis indicated that the initial product is a mix of chlorohydrin isomers. These undergo second addition of HOCl and/or lose halogens and polymerize. Additional minor products were also C5-C9 mono- and bifunctional carboxylates and mixed acid aldehydes. Studies with mol equiv of Cl- - free 36ClO- allowed estimation of covalent binding of Cl by L at various times, supporting the kinetic findings. For other PUFAs of higher degree unsaturation, the complexity of feasible reactions precluded an analogous approach.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. The rate of the productivity of human resources, capital, and energy in sub-sectors of industry during 1991-2011

    Directory of Open Access Journals (Sweden)

    Morteza Parandakh

    2015-12-01

    Full Text Available This study estimated the rate of productivity of human resources, capital, and energy (electricity in a selection of sub-sectors of industry (basic metals, chemicals, non-metallic minerals, rubber and plastic products, and food products during 1991-2011 using the econometric methods. For this purpose, first, the amount of the stability of the model's variables in time series was tested. Then, the existence of co-integration between them was determined and, finally, the productivity of the model was calculated using ARDL. According to the results, the elasticity of labor force, capital and energy were 1.07, 1.47 and -0.23, respectively.

  2. Optimization of aeration and agitation rate for lipid and gamma linolenic acid production by Cunninghamella bainieri 2A1 in submerged fermentation using response surface methodology.

    Science.gov (United States)

    Saad, Normah; Abdeshahian, Peyman; Kalil, Mohd Sahaid; Yusoff, Wan Mohtar Wan; Hamid, Aidil Abdul

    2014-01-01

    The locally isolated filamentous fungus Cunninghamella bainieri 2A1 was cultivated in a 5 L bioreactor to produce lipid and gamma-linolenic acid (GLA). The optimization was carried out using response surface methodology based on a central composite design. A statistical model, second-order polynomial model, was adjusted to the experimental data to evaluate the effect of key operating variables, including aeration rate and agitation speed on lipid production. Process analysis showed that linear and quadratic effect of agitation intensity significantly influenced lipid production process (P production (P production of lipid in the bioreactor.

  3. Effects of carbonyl bond, metal cluster dissociation, and evaporation rates on predictions of nanotube production in high-pressure carbon monoxide

    Science.gov (United States)

    Scott, Carl D.; Smalley, Richard E.

    2003-01-01

    The high-pressure carbon monoxide (HiPco) process for producing single-wall carbon nanotubes (SWNTs) uses iron pentacarbonyl as the source of iron for catalyzing the Boudouard reaction. Attempts using nickel tetracarbonyl led to no production of SWNTs. This paper discusses simulations at a constant condition of 1300 K and 30 atm in which the chemical rate equations are solved for different reaction schemes. A lumped cluster model is developed to limit the number of species in the models, yet it includes fairly large clusters. Reaction rate coefficients in these schemes are based on bond energies of iron and nickel species and on estimates of chemical rates for formation of SWNTs. SWNT growth is measured by the conformation of CO2. It is shown that the production of CO2 is significantly greater for FeCO because of its lower bond energy as compared with that of NiCO. It is also shown that the dissociation and evaporation rates of atoms from small metal clusters have a significant effect on CO2 production. A high rate of evaporation leads to a smaller number of metal clusters available to catalyze the Boudouard reaction. This suggests that if CO reacts with metal clusters and removes atoms from them by forming MeCO, this has the effect of enhancing the evaporation rate and reducing SWNT production. The study also investigates some other reactions in the model that have a less dramatic influence.

  4. Annual egg production rates of calanoid copepod species on the continental shelf of the Eastern Tropical Pacific off Mexico

    Science.gov (United States)

    Kozak, Eva R.; Franco-Gordo, Carmen; Palomares-García, Ricardo; Gómez-Gutiérrez, Jaime; Suárez-Morales, Eduardo

    2017-01-01

    We provide the first estimations of calanoid copepod egg production rates (EPR) in the Eastern Tropical Pacific over an annual cycle (January-December 2011). Gravid females were collected twice monthly and incubated for 12 h without food to estimate EPR, weight-specific fecundity (Gf), spawning success (SS, percentage of females to spawn out of the total species incubated per month and season) and egg hatching success (EHS). This study reports the average EPR of 10 species and the monthly EPR and Gf of four planktonic calanoid copepods (Centropages furcatus, Temora discaudata, Pontellina sobrina, and Nannocalanus minor) that spawned with enough frequency to infer their seasonal reproductive patterns. These species showed distinct seasonal reproductive strategies. Most copepod species spawned sporadically with large EPR variability, while three copepod species reproduced throughout the year (C. furcatus, T. discaudata and P. sobrina) and N. minor spawned only during the mixed period (Feb-May). The four species had relatively similar average EPR (C. furcatus 16, T. discaudata 18, P. sobrina 13, and N. minor 12 eggs fem-1 day-1). These are the first EPR estimations of P. sobrina and its previously known reproductive period is expanded. A Canonical Correspondence Analysis (CCA) was used to analyze EPR and species abundance of all calanoid copepods (40 spp.) collected throughout the time series in relation to temperature, salinity, mixed layer depth (MLD), dissolved oxygen, and chlorophyll a (Chl-a) concentrations to identify the variables that best explained the copepod abundance variability. Temperature, Chl-a, and salinity had the strongest effect on the biological variables, linked to seasonal and episodic upwelling-downwelling processes in the surveyed area. As a result of moderate upwelling events and seasonal variation of environmental conditions, it appears relatively few species are capable of maintaining continuous reproduction under the relatively higher

  5. Utilization of Anabaena sp. in CO{sub 2} removal processes. Modelling of biomass, exopolysaccharides productivities and CO{sub 2} fixation rate

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Fernandez, J.F.; Gonzalez-Lopez, C.V.; Acien Fernandez, F.G.; Fernandez Sevilla, J.M.; Molina Grima, E. [Almeria Univ. (Spain). Dept. of Chemical Engineering

    2012-05-15

    This paper focuses on modelling the growth rate and exopolysaccharides production of Anabaena sp. ATCC 33047, to be used in carbon dioxide removal and biofuels production. For this, the influence of dilution rate, irradiance and aeration rate on the biomass and exopolysaccharides productivity, as well as on the CO{sub 2} fixation rate, have been studied. The productivity of the cultures was maximum at the highest irradiance and dilution rate assayed, resulting to 0.5 g{sub bio} l{sup -1} day{sup -1} and 0.2 g{sub eps} l{sup -1} day{sup -1}, and the CO{sub 2} fixation rate measured was 1.0 gCO{sub 2} l{sup -1} day{sup -1}. The results showed that although Anabaena sp. was partially photo-inhibited at irradiances higher than 1,300 {mu}E m-2 s{sup -1}, its growth rate increases hyperbolically with the average irradiance inside the culture, and so does the specific exopolysaccharides production rate. The latter, on the other hand, decreases under high external irradiances, indicating that the exopolysaccharides metabolism hindered by photo-damage. Mathematical models that consider these phenomena have been proposed. Regarding aeration, the yield of the cultures decreased at rates over 0.5 v/v/min or when shear rates were higher than 60 s{sup -1}, demonstrating the existence of thus existence of stress damage by aeration. The behaviour of the cultures has been verified outdoors in a pilot-scale airlift tubular photobioreactor. From this study it is concluded that Anabaena sp. is highly recommended to transform CO{sub 2} into valuable products as has been proved capable of metabolizing carbon dioxide at rates of 1.2 gCO{sub 2} l{sup -1} day{sup -1} outdoors. The adequacy of the proposed equations is demonstrated, resulting to a useful tool in the design and operation of photobioreactors using this strain. (orig.)

  6. Effect of Injection Flow Rate on Product Gas Quality in Underground Coal Gasification (UCG Based on Laboratory Scale Experiment: Development of Co-Axial UCG System

    Directory of Open Access Journals (Sweden)

    Akihiro Hamanaka

    2017-02-01

    Full Text Available Underground coal gasification (UCG is a technique to recover coal energy without mining by converting coal into a valuable gas. Model UCG experiments on a laboratory scale were carried out under a low flow rate (6~12 L/min and a high flow rate (15~30 L/min with a constant oxygen concentration. During the experiments, the coal temperature was higher and the fracturing events were more active under the high flow rate. Additionally, the gasification efficiency, which means the conversion efficiency of the gasified coal to the product gas, was 71.22% in the low flow rate and 82.42% in the high flow rate. These results suggest that the energy recovery rate with the UCG process can be improved by the increase of the reaction temperature and the promotion of the gasification area.

  7. Production rate estimation of mycosporine-like amino acids in two Arctic melt ponds by stable isotope probing with NAH(13) CO3.

    Science.gov (United States)

    Ha, Sun-Yong; Min, Jun-Oh; Joo, Hyun Min; Chung, Kyung Ho; Shin, Kyung-Hoon; Yang, EunJin; Kang, Sung-Ho

    2014-10-01

    The net carbon uptake rate and net production rate of mycosporine-like amino acids (MAAs) were measured in phytoplankton from 2 different melt ponds (MPs; closed and open type pond) in the western Arctic Ocean using a (13) C stable isotope tracer technique. The Research Vessel Araon visited ice-covered western-central basins situated at 82°N and 173°E in the summer of 2012, when Arctic sea ice declined to a record minimum. The average net carbon uptake rate of the phytoplankton in polycarbonate (PC) bottles in the closed MP was 3.24 mg C · m(-3) · h(-1) (SD = ±1.12 mg C · m(-3) · h(-1) ), while that in the open MP was 1.3 mg C · m(-3) · h(-1) (SD = ±0.05 mg C · m(-3) · h(-1) ). The net production rate of total MAAs in incubated PC bottles was highest (1.44 (SD = ±0.24) ng C · L(-1) · h(-1) ) in the open MP and lowest (0.05 (SD = ±0.003) ng C · L(-1) · h(-1) ) in the closed MP. The net production rate of shinorine and palythine in incubated PC bottles at the open MP presented significantly high values 0.76 (SD = ±0.12) ng C · L(-1) · h(-1) and 0.53 (SD = ±0.06) ng C · L(-1) · h(-1) . Our results showed that high net production rate of MAAs in the open MP was enhanced by a combination of osmotic and UVR stress and that in situ net production rates of individual MAA can be determined using (13) C tracer in MPs in Arctic sea ice.

  8. Hemicellulosic Ethanol Production by Immobilized Wild Brazilian Yeast Scheffersomyces shehatae UFMG-HM 52.2: Effects of Cell Concentration and Stirring Rate.

    Science.gov (United States)

    Antunes, F A F; Santos, J C; Chandel, A K; Milessi, T S S; Peres, G F D; da Silva, S S

    2016-02-01

    The use of sugarcane bagasse hemicellulosic hydrolysates presents an interesting alternative to second generation (2G) ethanol production. Techniques to enhance the fermentation process, e.g., the use of immobilized cells, is one of the key factors for efficient production. Here, the effect of two important parameters (cell concentration in immobilized system and stirring rate) on the 2G ethanol production using the wild Brazilian yeast S. shehatae UFMG-HM 52.2 immobilized in calcium alginate matrix are presented. A 2(2) full factorial design of experiments was carried out to evaluate the effect of cell concentrations in sodium alginate solution for immobilized bead production (3.0, 6.0, and 9.0 g/L) and stirring rate (150, 200, and 250 rpm) for 2G ethanol production. Statistical analysis showed that the use of both variables at low levels enhanced ethanol yield (YP/S). Under these process conditions, YP/S of 0.31 g/g and ethanol productivity (Qp) of 0.12 g/L h were achieved. Results showed the potential of this immobilized yeast in 2G ethanol production from C5 sugars and demonstrate the importance of adequate cell concentration in immobilized systems, a finding that stands to increase bioprocesses yields and productivity.

  9. Estimates of rates and errors for measurements of direct-{gamma} and direct-{gamma} + jet production by polarized protons at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Tear Production Rate in a Mouse Model of Dry Eye According to the Phenol Red Thread and Endodontic Absorbent Paper Point Tear Tests.

    Science.gov (United States)

    Kilic, Servet; Kulualp, Kadri

    2016-01-01

    This study compared the endodontic absorbent paper point test (EAPTT) and the phenol red thread test (PRTT) for the assessment of tear production rate in a mouse model of dry eye. Fourteen BALB/c breed female mice were allocated into experimental and control groups of equal number. For 6 wk, the experimental group was kept in dry-eye cabinets, whereas the control group was kept in normal cages under ambient conditions. In both groups, the tear production rate was measured by using EAPTT and PRTT before the study, at study baseline, and at weeks 2, 4, and 6. Tear production at weeks 2, 4, and 6 differed significantly between groups and tests. Evaluating the groups independently in terms of the test technique revealed significant differences in tear production rate between the 2 groups at the same measurement times. Due to their persistent exposure to evaporative stress factors, the tear production rate of the mice in the dry-eye cabinet was consistently lower than that of controls. Unlike PRTT, EAPTT can be readily applied to the small globes of laboratory animals without the need for forceps, thus saving time and effort. In addition, EAPTT was practical and imposed no undue stress on the mice, due to the test material's firmer structure. Therefore, compared with PRTT, EAPTT is safer and more reliable for the diagnosis of dry-eye syndrome in mice.

  11. High efficiency cell-recycle continuous sodium gluconate production by Aspergillus niger using on-line physiological parameters association analysis to regulate feed rate rationally.

    Science.gov (United States)

    Lu, Fei; Li, Chao; Wang, Zejian; Zhao, Wei; Chu, Ju; Zhuang, Yingping; Zhang, Siliang

    2016-11-01

    In this paper, a system of cell-recycle continuous fermentation for sodium gluconate (SG) production by Aspergillus niger (A. niger) was established. Based on initial continuous fermentation result (100.0h) with constant feed rate, an automatic feedback strategy to regulate feed rate using on-line physiological parameters (OUR and DO) was proposed and applied successfully for the first time in the improved continuous fermentation (240.5h). Due to less auxiliary time, highest SG production rate (31.05±0.29gL(-1)h(-1)) and highest yield (0.984±0.067molmol(-1)), overall SG production capacity (975.8±5.8gh(-1)) in 50-L fermentor of improved continuous fermentation increased more than 300.0% compared to that of batch fermentation. Improvement of mass transfer and dispersed mycelia morphology were the two major reasons responsible for the high SG production rate. This system had been successfully applied to industrial fermentation and SG production was greatly improved.

  12. Effects of pH, hydraulic retention time and organic loading rate on biohydrogen production from the anaerobic fermentation of agri-food wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Won, S.; Lau, A. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Chemical and Biological Engineering

    2009-07-01

    This presentation reported on an experimental study in which biohydrogen was produced via anaerobic fermentation of dairy wastewater using a 6 L sequencing batch reactor. Tests were performed at ambient temperature and varying pH, hydraulic retention time (HRT) and organic loading rate (OLR). The seed sludge was not pretreated. The tests showed that methanogenic activity could be suppressed via short HRT and large OLR changes. However, the maximum hydrogen production rate was only 0.08 L/L per day without pH control. The rate of hydrogen production increased considerably when sucrose-rich synthetic wastewater was used as the substrate, and when pH was controlled. When HRT was reduced from 2.5 days to 1.25 days, observed hydrogen yield and hydrogen production rate reached 73 per cent and 4.38 L/L per day, respectively, for an optimal pH of 4.0. Volatile fatty acid was analyzed in order to determine the microbial metabolic pathway that favours increased hydrogen production. It was concluded that the co-fermentation of agri-food wastewater could improve the utilization of animal wastewater for the production of biohydrogen.

  13. Optimization of Aeration and Agitation Rate for Lipid and Gamma Linolenic Acid Production by Cunninghamella bainieri 2A1 in Submerged Fermentation Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Normah Saad

    2014-01-01

    Full Text Available The locally isolated filamentous fungus Cunninghamella bainieri 2A1 was cultivated in a 5 L bioreactor to produce lipid and gamma-linolenic acid (GLA. The optimization was carried out using response surface methodology based on a central composite design. A statistical model, second-order polynomial model, was adjusted to the experimental data to evaluate the effect of key operating variables, including aeration rate and agitation speed on lipid production. Process analysis showed that linear and quadratic effect of agitation intensity significantly influenced lipid production process (P<0.01. The quadratic model also indicated that the interaction between aeration rate and agitation speed had a highly significant effect on lipid production (P<0.01. Experimental results showed that a lipid content of 38.71% was produced in optimum conditions using an airflow rate and agitation speed of 0.32 vvm and 599 rpm, respectively. Similar results revealed that 0.058 (g/g gamma-linolenic acid was produced in optimum conditions where 1.0 vvm aeration rate and 441.45 rpm agitation rate were used. The regression model confirmed that aeration and agitation were of prime importance for optimum production of lipid in the bioreactor.

  14. Expected measurement of the Z production rate with the CMS detector and simulation of the Tracker Laser Alignment System

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Maarten

    2009-06-16

    The Large Hadron Collider is a two-ring, superconducting accelerator and collider which can provide both proton and heavy-ion beams. First collisions are foreseen for 2009. The Compact Muon System (CMS) detector will measure the particles created in the hadron collisions and can confirm the Standard Model by establishing the existence of the Higgs boson, but also search for new phenomena. In order to provide a robust and precise track reconstruction, which can already be used in the High-Level Trigger systems, the positions of the silicon sensors in the CMS tracker have to been known with an accuracy of O(100 {mu}m). Therefore the CMS tracker has been equipped with a dedicated alignment system. The Laser Alignment System (LAS) aligns the tracker subdetectors with respect to each other and can also monitor the stability of the sensor positions during data taking. This study describes the implementation of a realistic simulation of the LAS in the CMS software framework (CMSSW) as well as the analysis of the first data collected during the integration of one of the tracker endcaps. In the present study it has been found that the alignment of the endcaps is possible with an accuracy of approximately 76 {mu}m. These results are in agreement with independent measurements of the TEC geometry using cosmic muons or photogrammetry measurements. The accuracy of approximately 100 {mu}m needed for track pattern recognition and reconstruction can be assured by the Laser Alignment System as shown in this study. Accurate knowledge of the luminosity delivered by the LHC to the experiments is an essential ingredient for many physics studies. The present work uses the production of lepton pairs via the Drell-Yan mechanism to determine the integrated luminosity with the CMS detector. A Monte Carlo generator (MC rate at NLO) including next-to-leading order QCD diagrams has been used to generate Drell-Yan events decaying into two muons. After a full CMS detector simulation, the events

  15. Effects of solids concentration, pH and carbon addition on the production rate and composition of volatile fatty acids in prefermenters using primary sewage sludge

    DEFF Research Database (Denmark)

    Zeng, Raymond Jianxiong; Yuan, Z.; Keller, J.

    2006-01-01

    in prefermenters. In this study, a series of controlled batch experiments were conducted with sludge from a full-scale prefermenter to determine the impact of solids concentration, pH and addition of molasses on prefermentation processes. It was found that an increase in solids concentration enhanced total VFA...... production with an increased propionic acid fraction. The optimal pH for prefermentation was in the range of 6-7 with significant productivity loss when pH was below 5.5. Molasses addition significantly increased the production of VFAs particularly the propionic acid. However, the fermentation rate...

  16. 75 FR 42605 - Increase in Tax Rates on Tobacco Products and Cigarette Papers and Tubes; Floor Stocks Tax on...

    Science.gov (United States)

    2010-07-22

    ... Part 41 Cigars and cigarettes, Claims, Customs duties and inspection, Electronic funds transfers... Products and Cigarette Papers and Tubes; Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes; and Changes to Basis for Denial, Suspension, or Revocation of Permits...

  17. Assessment of metabolic properties and kinetic parameters of methanogenic sludge by on-line methane production rate measurements

    NARCIS (Netherlands)

    Gonzalez-Gil, G.; Kleerebezem, R.; Lettinga, G.

    2002-01-01

    This report presents a new approach to studying the metabolic and kinetic properties of anaerobic sludge from single batch experiments. The two main features of the method are that the methane production is measured on-line with a relatively cheap system, and that the methane production data can be

  18. Hydrogen production with high yield and high evolution rate by self-flocculated cells of Enterobacter aerogenes in a packed-bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Rachman, M.A.; Nakashimada, Y.; Kakizono, T.; Nishio, N. [Hiroshima Univ. (Japan). Graduate Sch. of Eng.

    1998-09-01

    Continuous hydrogen gas evolution by self-flocculated cells of Enterobacter aerogenes, a natural isolate HU-101 and its mutant AY-2, was performed in a packed-bed reactor under glucose-limiting conditions in a minimal medium. The flocs that formed during the continuous culture were retained even when the dilution rate was increased to 0.9 h{sup -1}. The H{sub 2} production rate increased linearly with increases in the dilution rate up to 0.67 h{sup -1}, giving maximum H{sub 2} production rates of 31 and 58 mmol l{sup -1} h{sup -1} in HU-101 and AY-2 respectively, at a dilution rate of more than 0.67 h{sup -1}. The molar H{sub 2} yield from glucose in AY-2 was maintained at about 1.1 at dilution rates between 0.08 h{sup -1} and 0.67 h{sup -1}, but it decreased rapidly at dilution rates more than 0.8 h{sup -1}. (orig.)

  19. Interaction of heat production, strain rate and stress power in a plastically deforming body under tensile test

    Science.gov (United States)

    Paglietti, A.

    1982-01-01

    At high strain rates the heat produced by plastic deformation can give rise to a rate dependent response even if the material has rate independent constitutive equations. This effect has to be evaluated when interpreting a material test, or else it could erroneously be ascribed to viscosity. A general thermodynamic theory of tensile testing of elastic-plastic materials is given in this paper; it is valid for large strain at finite strain rates. It enables discovery of the parameters governing the thermodynamic strain rate effect, provides a method for proper interpretation of the results of the tests of dynamic plasticity, and suggests a way of planning experiments in order to detect the real contribution of viscosity.

  20. Sites and mechanisms responsible for the low rate of free radical production of heart mitochondria in the long-lived pigeon.

    Science.gov (United States)

    Herrero, A; Barja, G

    1997-11-01

    Basal (substrate alone) and maximum rates of H2O2 production, oxygen consumption and free radical leak in the respiratory chain were higher in heart mitochondria of the short-lived rat (4 years) than in the long-lived pigeon (35 years). This suggests that the low free radical production of pigeon heart mitochondria is due in part to both a low electron flow and a low percent leak of electrons out of sequence in the respiratory chain. Thenoyltrifluoroacetone did not increase H2O2 production with succinate either in rats or pigeons. Mitochondrial H2O2 production was higher with pyruvate/malate than with succinate in both animal species. Rotenone and antimycin A increased H2O2 production with pyruvate/malate to the maximum levels observed in each species. Addition of myxothiazol to antimycin A-treated mitochondria supplemented with pyruvate/malate decreased H2O2 production in both species. All the combinations of inhibitors added with pyruvate/malate resulted in higher rates of H2O2 production in rats than in pigeons. When succinate instead of pyruvate/malate was used as substrate, rotenone and thenoyltrifluoroacetone decreased mitochondrial H2O2 production in the rat and did not change it in the pigeon. The results indicate that Complexes I and III are the main H2O2 generators of heart mitochondria in rats and pigeons and that both Complexes are responsible for the low H2O2 production of the bird. p-Chloromercuribenzoate and ethoxyformic anhydride strongly inhibited the H2O2 production induced by rotenone with pyruvate/malate in both species. This suggests that the free radical generator of Complex I is located after the ferricyanide reduction site, between the ethoxyformic and the rotenone-sensitive sites.

  1. Influence of food preservation parameters and associated microbiota on production rate, profile and stability of acylated homoserine lactones from food-derived Enterobacteriaceae

    DEFF Research Database (Denmark)

    Flodgaard, Lars; Christensen, Allan Beck; Molin, Søren;

    2003-01-01

    of carbon source (glucose,, sucrose, xylose, arabinose, mannose, mannitol and sorbitol), temperature (5 and 25 degreesC), salt concentration (0-7%), pH (6, 7 and 8) and co-existing lactic acid bacteria microflora on the AHL profile and production rate from Serratia proteamaculans strain B5a and Enterobacter...

  2. Evaluating effects of tannins on extent and rate of in vitro gas and CH4, production using an automated pressure evaluation system (APES)

    NARCIS (Netherlands)

    Pellikaan, W.F.; Stringano, E.; Leenaars, J.; Bongers, L.J.G.M.; Laar-van Schuppen, van S.; Plant, J.; Mueller-Harvey, I.

    2011-01-01

    An in vitro study was conducted to investigate effects of tannins on extent and rate of gas and CH4 production using an automated pressure evaluation system (APES). In this study three condensed tannins (CT; quebracho, grape seed, green tea tannins) and four hydrolysable tannins (HT; tara, valonea,

  3. WholeTree Substrate and Fertilizer Rate in Production of Greenhouse Grown Petunia (Petunia*hybrida Vilm) and marigold (Tagetes patula L.)

    Science.gov (United States)

    A substrate component (WholeTree) made from loblolly pine (Pinus taeda L.) was evaluated along with starter fertilizer rate in the production of greenhouse-grown petunia (Petunia 'hybrida Vilm. ‘Dreams Purple’) and marigold (Tagetes patula L. ‘Hero Spry’). Loblolly pine from a 12 year old plantation...

  4. High sedimentation rates in the Early Triassic after latest Permian mass extinction: Carbonate production is main factor in non-Arctic regions

    Science.gov (United States)

    Horacek, Micha; Brandner, Rainer

    2016-04-01

    A substantial change in sedimentation rates towards higher values has been documented from the Late Permian to the Lower Triassic. Although it is assumed and also has been shown that the deposition of siliciclastic material increased in the Lower Triassic due to stronger erosion because of loss of land cover and increased chemical and physical weathering with extreme climate warming, the main sediment production occurred by marine carbonate production. Still, carbonate production might have been significantly influenced by weathering and erosion in the hinterland, as the transport of dust by storms into the ocean water probably was a main nutrient source for microbial carbonate producers, because "normal" nutrient supply by ocean circulation, i. e. upwelling was strongly reduced due to the elevated temperatures resulting in water-column stratification . Sediment accumulation was also clearly influenced by the paleo-geographic and latitudinal position, with lower carbonate production and sedimentation rates in moderate latitudes. The existence of a "boundary clay" and microbial carbonate mounds and layers in the immediate aftermath of the latest Permian mass extinction points towards a development from a short-timed acid ocean water - resulting in a carbonate production gap and the deposition of the boundary clay towards the deposition of the microbial mounds and layers due to the microbial production of micro-environments with higher alkalinity allowing the production of carbonate. After the return of the ocean water to normal alkalinity planktic production of carbonate resulted in a very high sedimentation rate, especially taking into account the absence of carbonate producing eukaryotic algae and animals.

  5. Asparagus stem as a new lignocellulosic biomass feedstock for anaerobic digestion: increasing hydrolysis rate, methane production and biodegradability by alkaline pretreatment.

    Science.gov (United States)

    Chen, Xiaohua; Gu, Yu; Zhou, Xuefei; Zhang, Yalei

    2014-07-01

    Recently, anaerobic digestion of lignocellulosic biomass for methane production has attracted considerable attention. However, there is little information regarding methane production from asparagus stem, a typical lignocellulosic biomass, by anaerobic digestion. In this study, alkaline pretreatment of asparagus stem was investigated for its ability to increase hydrolysis rate and methane production and to improve biodegradability (BD). The hydrolysis rate increased with increasing NaOH dose, due to higher removal rates of lignin and hemicelluloses. However, the optimal NaOH dose was 6% (w/w) according to the specific methane production (SMP). Under this condition, the SMP and the technical digestion time of the NaOH-treated asparagus stem were 242.3 mL/g VS and 18 days, which were 38.4% higher and 51.4% shorter than those of the untreated sample, respectively. The BD was improved from 40.1% to 55.4%. These results indicate that alkaline pretreatment could be an efficient method for increasing methane production from asparagus stem.

  6. Changes in the egg production rate of two copepod species of the genus Pseudocalanus in relation to temperature in the White Sea

    Science.gov (United States)

    Ershova, E. A.; Kosobokova, K. N.; Vorobieva, O. V.

    2016-07-01

    This study examines changes in egg production rates of two co-occurring Pseudocalanus species, P. acuspes and P. minutus, in response to changing temperatures (0, 3, 6, 9 and 12°C) in the White Sea. The boreal P. acuspes (sample size >650 individuals) increased its reproductive rate gradually across the entire range of temperatures from 0 to 12°C. Significant differences in egg production rates and reaction to temperature were also observed between P. acuspes females incubated during the early vs. the mid-summer season. The sample size of the Arctic P. minutus was significantly smaller due to the low numbers at which this species occurred. However, the results suggest that this species increases its egg production rates from 0 to 3°C from 3.3 to 8.5% dry weight female-1 day-1, but at 9° its reproductive rate drops significantly and the animals demonstrate markedly reduced fitness. Our results indicate that closely related co-occurring species, and even different generations within one species, can demonstrate significantly different responses to changes in the physical environment.

  7. A fuzzy-logic-based model to predict biogas and methane production rates in a pilot-scale mesophilic UASB reactor treating molasses wastewater.

    Science.gov (United States)

    Turkdogan-Aydinol, F Ilter; Yetilmezsoy, Kaan

    2010-10-15

    A MIMO (multiple inputs and multiple outputs) fuzzy-logic-based model was developed to predict biogas and methane production rates in a pilot-scale 90-L mesophilic up-flow anaerobic sludge blanket (UASB) reactor treating molasses wastewater. Five input variables such as volumetric organic loading rate (OLR), volumetric total chemical oxygen demand (TCOD) removal rate (R(V)), influent alkalinity, influent pH and effluent pH were fuzzified by the use of an artificial intelligence-based approach. Trapezoidal membership functions with eight levels were conducted for the fuzzy subsets, and a Mamdani-type fuzzy inference system was used to implement a total of 134 rules in the IF-THEN format. The product (prod) and the centre of gravity (COG, centroid) methods were employed as the inference operator and defuzzification methods, respectively. Fuzzy-logic predicted results were compared with the outputs of two exponential non-linear regression models derived in this study. The UASB reactor showed a remarkable performance on the treatment of molasses wastewater, with an average TCOD removal efficiency of 93 (+/-3)% and an average volumetric TCOD removal rate of 6.87 (+/-3.93) kg TCOD(removed)/m(3)-day, respectively. Findings of this study clearly indicated that, compared to non-linear regression models, the proposed MIMO fuzzy-logic-based model produced smaller deviations and exhibited a superior predictive performance on forecasting of both biogas and methane production rates with satisfactory determination coefficients over 0.98.

  8. Effect of environmental forcing on the biomass, production and growth rate of size-fractionated phytoplankton in the central Atlantic Ocean

    Science.gov (United States)

    Huete-Ortega, María; Calvo-Díaz, Alejandra; Graña, Rocío; Mouriño-Carballido, Beatriz; Marañón, Emilio

    2011-11-01

    To ascertain the response of phytoplankton size classes to changes in environmental forcing, we determined size-fractionated biomass, carbon fixation and growth (production/biomass) rates in surface waters along the central Atlantic Ocean (26°N-5°S). As a result of the enhanced input of nutrients into the euphotic layer and the higher water column stability found at the equatorial upwelling, we observed increases not only in phytoplankton biomass and primary production, but also in turnover rates, suggesting nutrient limitation of phytoplankton physiology in the oligotrophic central Atlantic. The phytoplankton groups analysed (pico-, small nano-, large nano- and micro-phytoplankton) showed different responses to the equatorial environmental forcing, in terms of carbon biomass, primary production and growth rate. Large nano- and micro-phytoplankton consistently showed higher growth rates and carbon fixation to chl a ratios than smaller phytoplankton. We observed a higher stimulating effect of increased nitrate supply on the small phytoplankton growth rates. This observation can be explained by the dynamics of the equatorial upwelling, where the continuous but small nutrient input into the euphotic layer provide a competitive advantage for smaller cells adapted to oligotrophic conditions. The size-fractionated approach shown here reveals important group-specific differences in the response to environmental forcing, which cannot be appreciated in bulk measurements of the whole community.

  9. Power corrections to the electromagnetic spectral function and the dilepton rate in QCD plasma within operator product expansion in D=4

    CERN Document Server

    Bandyopadhyay, Aritra

    2016-01-01

    We evaluate the electromagnetic spectral function in QCD plasma in a nonperturbative background of in-medium quark and gluon condensates by incorporating the leading order power corrections in a systematic framework within the ambit of the operator product expansion in D=4 dimension. We explicitly show that the mixing of the composite operators removes mass singularities and renders Wilson coefficients finite and well defined. As a spectral property, we then obtain the nonperturbative dilepton production rate from QCD plasma. The operator product expansion automatically restricts the dilepton rate to the intermediate mass range, which is found to be enhanced due to the power corrections. We also compare our result with those from nonperturbative calculations, e.g., lattice QCD and effective QCD models based on Polyakov loop.

  10. Disparities between Phaeocystis in situ and optically-derived carbon biomass and growth rates: potential effect on remote-sensing primary production estimates

    Directory of Open Access Journals (Sweden)

    L. Peperzak

    2014-04-01

    Full Text Available The oceans play a pivotal role in the global carbon cycle. Unfortunately, the daily production of organic carbon, the product of phytoplankton standing stock and growth rate cannot be measured globally by discrete oceanographic methods. Instead, optical proxies from Earth-orbiting satellites must be used. To test the accuracy of optically-derived proxies of phytoplankton physiology and growth rate, standard ex situ data from the wax and wane of a Phaeocystis bloom in laboratory mesocosms were compared with hyperspectral reflectance data. Chlorophyll biomass could be estimated accurately from reflectance using specific chlorophyll absorption algorithms. However, the conversion of chlorophyll (Chl to carbon (C was obscured by the observed increase in C : Chl under nutrient-limited growth. C : Chl was inversely correlated (r2 = 0.88 with Photosystem II quantum efficiency (Fv/Fm, the in situ fluorometric oceanographic proxy for growth rate. In addition, the optical proxy for growth rate, the quantum efficiency of fluorescence ϕ was linearly correlated to Fv/Fm (r2 = 0.84, but not – as by definition – by using total phytoplankton absorption, because during nutrient-limited growth the concentrations of non-fluorescent light-absorbing pigments increased. As a consequence, none of the three proxies (C : Chl, Fv/Fm, φ was correlated to carbon or cellular phytoplankton growth rates. Therefore, it is concluded that although satellite derived estimates of chlorophyll biomass may be accurate, physiologically-induced non-linear shifts in growth rate proxies may obscure accurate phytoplankton growth rates and hence global carbon production estimates.

  11. Cosmogenic 10Be production rate calibrated against 3He in the high Tropical Andes (3800-4900 m, 20-22° S)

    Science.gov (United States)

    Blard, P.-H.; Braucher, R.; Lavé, J.; Bourlès, D.

    2013-11-01

    Many geomorphologic applications, notably glacier chronologies, require improvements in both the precision and the accuracy of the cosmogenic dating tool. Of particular importance is the need to better constrain the spatial variability of the cosmogenic nuclides production rates at high elevation and low latitudes. One strategy that can be adopted for this is to couple absolute calibrations, from independently dated surfaces, with cross-calibration studies, performed by measuring several cosmogenic nuclides in the same rock. In the present study, we report the highest-elevation (>4800 m) cross-calibration published to date, comprising measurements of cosmogenic 3He and 10Be in cogenetic pyroxene and quartz. The samples were collected from six dacitic moraine boulders, exposed from 32 to 65 ka at 4820 m on the flanks of the Uturuncu volcano (22° S, 67° W), Southern Lipez (Bolivia). The samples yield a remarkably tight cluster of 3He-10Be production ratios, with a weighted mean of 33.3±0.9 (1σ). This production ratio is undistinguishable, within uncertainties, from the 3He-10Be production ratio of 32.3±0.9 determined in the same mineral pair at low elevation (1333 m) by Amidon et al. (2009). These results agree at the 1σ level and suggest that any hypothetical increase of the 3He-10Be production ratio in pyroxene and quartz is likely to be lower than 5% over this elevation range (1000-5000 m). Moreover, the production ratio is almost insensitive to the Li content of the pyroxene (20 to 50 ppm Li), suggesting that the cosmogenic thermal neutron production of 3He is very low in this setting. The high-elevation 3He-10Be production ratio is used in combination with a local determination of the 3He production rate in the high Central Altiplano (3800 m) (Blard et al., 2013) to establish a local 10Be production rate of 30.0±1.4 at g yr at 3800 m and 20° S. After scaling to sea-level high latitude with the time-dependent Lal/Stone model, this yields a 10Be production

  12. Culture medium pH influence on Gluconacetobacter physiology: Cellulose production rate and yield enhancement in presence of multiple carbon sources.

    Science.gov (United States)

    Yassine, Fatima; Bassil, Nathalie; Flouty, Roula; Chokr, Ali; Samrani, Antoine El; Boiteux, Gisèle; Tahchi, Mario El

    2016-08-01

    Gluconacetobacter genera are valued for bacterial cellulose (BC) and acetic acid production. BC is produced at optimal yields in classical microbiological media that are expensive for a large scale of production. In addition, BC usage for industrial purposes is limited due to low conversion rate into cellulose and to long incubation duration. In this paper, Gluconacetobacter isolated from apple vinegar was kinetically studied to evaluate cellulose production in presence of different carbon sources. Acetic and citric acid effect on Gluconacetobacter metabolism is clarified. It was shown that Gluconacetobacter uses glucose as a primary carbon source for cells growth and products formation. Acetic acid employment as a co-carbon source in Hestrin Schramm medium showed an increase of 17% in BC yield with a moderate decrease in the crystallite size of the resulting polymer.

  13. Ammonium and nitrate uptake, nitrogen productivity and biomass allocation in interior spruce families with contrasting growth rates and mineral nutrient preconditioning.

    Science.gov (United States)

    Miller, Brad D; Hawkins, Barbara J

    2007-06-01

    Four full-sib families of interior spruce (Picea glauca (Moench) Voss) x Picea engelmanii Parry ex Engelm.) with contrasting growth rates (two fast-growing and two slow-growing families) were grown aeroponically with either a 2% relative nitrogen addition rate or free access to nitrogen. Fast-growing families showed greater plasticity in allocating biomass to shoots at high nitrogen supply and to roots at low nitrogen supply than slow-growing families. Compared with the slow-growing families, short-term net ammonium uptake rate measured with an ion selective electrode was significantly greater in fast-growing families at high ammonium supply, but not at low supply. Net nitrate uptake showed the same trend, but differences among families were not significant. Results indicate that differences in seedling growth rate are partly a result of physiological differences in net nitrogen uptake efficiency and nitrogen productivity.

  14. Measurement of tritium production rate distribution in natural LiAlO{sub 2}/HDPE assembly irradiated by D-T neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Jakhar, Shrichand, E-mail: shrichand.s@gmail.com [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Abhangi, Mitul; Rao, C.V.S.; Basu, T.K. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Bhade, Sonali P.D.; Reddy, Priyanka J. [Radiation Safety Systems Division, Bhabha Atomic Research Center, Trombay, Mumbai (India)

    2012-02-15

    A neutronics experiment was performed to measure the tritium production rate (TPR) profile in the breeder assembly with LiAlO{sub 2} as breeder and high density polyethylene (HDPE) as neutron reflector. The breeder assembly was irradiated with 14 MeV neutrons from DT neutron generator at IPR Neutronics Laboratory. The objective of the experiment was to validate the tritium production prediction capability of the Monte-Carlo code MCNP and FENDL 2.1 data library. The tritium production rate profile in the breeding assembly was measured by irradiating Li{sub 2}CO{sub 3} pellets kept at various locations and then tritium counting liquid scintillation technique. Experiment was analyzed with 3D Monte-Carlo code MCNP with FENDL 2.1 cross-section data library. The calculation results were found to agree with the measured tritium production rates except one point near to the source. This experiment is a starting experiment in the series of benchmark experiments for the Indian Demo breeding blanket.

  15. A risk microbiological profile of the Australian red meat industry: risk ratings of hazard-product pairings.

    Science.gov (United States)

    Sumner, John; Ross, Tom; Jenson, Ian; Pointon, Andrew

    2005-11-25

    A risk profile of microbial hazards across the supply continuum for the beef, sheep and goat meat industries was developed using both a qualitative tool and a semi-quantitative, spreadsheet tool, Risk Ranger. The latter is useful for highlighting factors contributing to food safety risk and for ranking the risk of various product/pathogen combinations. In the present profile the qualitative tool was used as a preliminary screen for a wide range of hazard-product pairings while Risk Ranger was used to rank in order of population health risk pairings for which quantitative data were available and for assessing the effect of hypothetical scenarios. 'High' risk hazard-product pairings identified were meals contaminated with Clostridium perfringens provided by caterers which have not implemented HACCP; kebabs cross-contaminated by Salmonella present in drip trays or served undercooked; meals served in the home cross-contaminated with Salmonella. 'Medium' risk hazard-product pairings identified were ready-to-eat meats contaminated with Listeria monocytogenes and which have extended shelf life; Uncooked Comminuted Fermented Meat (UCFM)/Salami contaminated with Enterohaemorrhagic E. coli (EHEC) and Salmonella; undercooked hamburgers contaminated with EHEC; kebabs contaminated by Salmonella under normal production or following final "flash" heating. Identified 'low' risk hazard-product pairings included cooked, ready-to-eat sausages contaminated with Salmonella; UCFM/Salami contaminated with L. monocytogenes; well-cooked hamburgers contaminated with EHEC. The risk profile provides information of value to Australia's risk managers in the regulatory, processing and R&D sectors of the meat and meat processing industry for the purposes of identifying food safety risks in the industry and for prioritising risk management actions.

  16. High rate biomethanation technology for solid waste management and rapid biogas production: An emphasis on reactor design parameters.

    Science.gov (United States)

    Dahiya, Shikha; Joseph, Johny

    2015-01-01

    A high rate biomethanation digester was designed and fabricated to study its real field treatment efficiency and simultaneous biogas generation. The major design parameters like self mixing, delinking hydraulic retention time and solid retention time etc. were considered for efficient performance. It was operated with an organic loading rate (OLR) of 1.5kg/m(3)d(-1) with composite food waste for about one year. The maximum treatment efficiency achieved with respect to total solid (TS) reduction and volatile solids (VS) reduction was 94.5% and 89.7%, respectively. Annual mean biogas of about 0.16m(3)/kgVSd(-1) was observed with methane content varying from 56% to 60% (v/v). The high competence of high rate digester is attributed to its specific design features and intermittent mixing of the digester contents and also due to the hydrodynamic principles involved in its operation.

  17. Research on the Financial Products and their Influence on Interest Rate Liberalization%理财产品与利率市场化效率研究

    Institute of Scientific and Technical Information of China (English)

    容玲

    2012-01-01

    本文运用SPSS逐步回归法做计量模型分析了储蓄存款转为理财产品的转化率,并理论剖析了理财产品的特征及其对存款替代效应的影响因素.研究得出结论:理财投资对储蓄存款的替代效应较大,对金融机构绕过存款利率上限管制、推进利率市场化进程具有重要意义.作为主导利率市场化改革的人民银行,应规范理财产品业务运营管理,加快推进市场化产品的研发和推广,在政策透明的前提下推动金融深化.%In this essay, an econometrical analysis is conducted to calculate the percentage of savings deposit converted to financial products investment using stepwise regression method on SPSS. The essay also discusses theoretically the characteristics of financing products and the influencing factors on the substitution effect of financing products for savings deposit. Finally, it is concluded that the financing products have a strong substitution effect on savings deposit and are of great significance for the financial institutions to circumvent the deposit interest rate caps and push forward the process of interest rate liberalization. Consequently, the People' s Bank of China, which guides China' s reform towards market-driven interest rates, shall without any doubt regulate the financing products market and speed up the research, development and popularization of investment vehicles embedded with market-driven interest rates. Such efforts are expected to promote financial deepening on the premise of transparent policies.

  18. Oxygen transfer rate during the production of alginate by Azotobacter vinelandii under oxygen-limited and non oxygen-limited conditions

    Directory of Open Access Journals (Sweden)

    Peña Carlos F

    2011-02-01

    Full Text Available Abstract Background The oxygen transfer rate (OTR and dissolved oxygen tension (DOT play an important role in determining alginate production and its composition; however, no systematic study has been reported about the independent influence of the OTR and DOT. In this paper, we report a study about alginate production and the evolution of the molecular mass of the polymer produced by a wild-type A. vinelandii strain ATCC 9046, in terms of the maximum oxygen transfer rate (OTRmax in cultures where the dissolved oxygen tension (DOT was kept constant. Results The results revealed that in the two dissolved oxygen conditions evaluated, strictly controlled by gas blending at 0.5 and 5% DOT, an increase in the agitation rate (from 300 to 700 rpm caused a significant increase in the OTRmax (from 17 to 100 mmol L-1 h-1 for DOT of 5% and from 6 to 70 mmol L-1 h-1 for DOT of 0.5%. This increase in the OTRmax improved alginate production, as well as the specific alginate production rate (SAPR, reaching a maximal alginate concentration of 3.1 g L-1 and a SAPR of 0.031 g alg g biom-1 h-1 in the cultures at OTRmax of 100 mmol L-1 h-1. In contrast, the mean molecular mass (MMM of the alginate isolated from cultures developed under non-oxygen limited conditions increased by decreasing the OTRmax, reaching a maximal of 550 kDa at an OTRmax of 17 mmol L-1 h-1 . However, in the cultures developed under oxygen limitation (0.5% DOT, the MMM of the polymer was practically the same (around 200 kDa at 300 and 700 rpm, and this remained constant throughout the cultivation. Conclusions Overall, our results showed that under oxygen-limited and non oxygen-limited conditions, alginate production and its molecular mass are linked to the OTRmax, independently of the DOT of the culture.

  19. Validation and recovery rates of an indirect calorimetry headbox system used to measure heat production of cattle

    Science.gov (United States)

    A headbox system was constructed at the University of Nebraska-Lincoln to determine heat production from dairy cattle using indirect calorimetry. The system was designed for use in a tie-stall barn to allow the animal to be comfortable and was mounted on wheels to transport between animals between s...

  20. Gender Gaps in North American Research Productivity: Examining Faculty Publication Rates in Mexico, Canada, and the U.S.

    Science.gov (United States)

    Padilla-Gonzalez, Laura; Metcalfe, Amy Scott; Galaz-Fontes, Jesus F.; Fisher, Donald; Snee, Iain

    2011-01-01

    The present study addresses gender gaps in North American research productivity, which may be influenced by personal and family variables, as well as professional and work-related variables. The study was conducted as part of the "Changing Academic Profession (CAP) International Survey", conducted in 2007-08. Using articles as indicator…

  1. Buffalo behaviour at milking parlor in relation to production rates and adaptability to the environment: a review

    Directory of Open Access Journals (Sweden)

    Juliana Paula Felipe de Oliveira

    2013-07-01

    Full Text Available Buffaloes have become an economically viable source of protein, due to its adaptability, precocity and longevity. The dogma that high productivity cannot be related with the animal welfare needs to be effectively broken down by making the producers aware, based on education and science, of the appropriate treatment to animals favors the productivity. To high milk production buffaloes and with ability for milking, this happens without suckling calves which are artificially suckled. This technique, when not properly performed, can provide negative consequences, like difficulties in animal adaptation to the milking environment, especially those who are facing this experience for the first time, like primiparous buffaloes. The development of methods for temperament evaluation added to management improvements in the productive unit is valuable to improve the welfare conditions for animals. The behavioral observation in the milking environment is a very important tool for the determination of the animal's temperamental score which, in turn, is substantial to determine the level of welfare and conditioning/performance in this activity, and thus minimizing problems and negative consequences for animal handlers, animals and producer

  2. On the Relationship between Observed NLDN Lightning Strikes and Modeled Convective Precipitation Rates Parameterization of Lightning NOx Production in CMAQ

    Science.gov (United States)

    Lightning-produced nitrogen oxides (NOX=NO+NO2) in the middle and upper troposphere play an essential role in the production of ozone (O3) and influence the oxidizing capacity of the troposphere. Despite much effort in both observing and modeling lightning NOX during the past dec...

  3. Growth-rate dependency of de novo resveratrol production in chemostat cultures of an engineered Saccharomyces cerevisiae strain

    NARCIS (Netherlands)

    Vos, T.; De la Torre Cortes, P.; Van Gulik, W.M.; Pronk, J.T.; Daran-Lapujade, P.A.S.

    2015-01-01

    Introduction: Saccharomyces cerevisiae has become a popular host for production of non-native compounds. The metabolic pathways involved generally require a net input of energy. To maximize the ATP yield on sugar in S. cerevisiae, industrial cultivation is typically performed in aerobic, sugar-limit

  4. Can Morasko and Mundrabilla help Reconstructing Production Rates and Nuclear Reaction Cross-Sections for Light Cosmogenic Nuclides?

    Science.gov (United States)

    Merchel, S.; Smith, T.; Leya, I.; Pavetich, S.; Rugel, G.; Scharf, A.; Muszynski, A.

    2016-08-01

    Lighter nuclides of He, Ne, and Ar, and radionuclides Be-10, Al-26, Cl-36 and Ca-41 are measured in troilite, schreibersite and bulk metal of Mundrabilla and Morasko. Traces of S largely enhance Al-26 production. Cl-36-Ar-36 CRE ages are undisturbed.

  5. Complete genome sequence of Enterobacter sp. IIT-BT 08: A potential microbial strain for high rate hydrogen production.

    Science.gov (United States)

    Khanna, Namita; Ghosh, Ananta Kumar; Huntemann, Marcel; Deshpande, Shweta; Han, James; Chen, Amy; Kyrpides, Nikos; Mavrommatis, Kostas; Szeto, Ernest; Markowitz, Victor; Ivanova, Natalia; Pagani, Ioanna; Pati, Amrita; Pitluck, Sam; Nolan, Matt; Woyke, Tanja; Teshima, Hazuki; Chertkov, Olga; Daligault, Hajnalka; Davenport, Karen; Gu, Wei; Munk, Christine; Zhang, Xiaojing; Bruce, David; Detter, Chris; Xu, Yan; Quintana, Beverly; Reitenga, Krista; Kunde, Yulia; Green, Lance; Erkkila, Tracy; Han, Cliff; Brambilla, Evelyne-Marie; Lang, Elke; Klenk, Hans-Peter; Goodwin, Lynne; Chain, Patrick; Das, Debabrata

    2013-12-20

    Enterobacter sp. IIT-BT 08 belongs to Phylum: Proteobacteria, Class: Gammaproteobacteria, Order: Enterobacteriales, Family: Enterobacteriaceae. The organism was isolated from the leaves of a local plant near the Kharagpur railway station, Kharagpur, West Bengal, India. It has been extensively studied for fermentative hydrogen production because of its high hydrogen yield. For further enhancement of hydrogen production by strain development, complete genome sequence analysis was carried out. Sequence analysis revealed that the genome was linear, 4.67 Mbp long and had a GC content of 56.01%. The genome properties encode 4,393 protein-coding and 179 RNA genes. Additionally, a putative pathway of hydrogen production was suggested based on the presence of formate hydrogen lyase complex and other related genes identified in the genome. Thus, in the present study we describe the specific properties of the organism and the generation, annotation and analysis of its genome sequence as well as discuss the putative pathway of hydrogen production by this organism.

  6. Sociable swine : indirect genetic effects on growth rate and their effect on behaviour and production of pigs in different environments

    NARCIS (Netherlands)

    Camerlink, I.

    2014-01-01

    Social interactions between pigs can influence their health, welfare, and productivity. The effects of social interactions on individuals are partly genetic, and this genetic effect is known as an Indirect Genetic Effect. IGEs are thus the heritable effects of an individual on the trait values of it

  7. Selectively reducing offshore royalty rates in the Gulf of Mexico could increase oil production and federal government revenue

    Energy Technology Data Exchange (ETDEWEB)

    Bowsher, C.A.

    1985-05-10

    The US government leases large areas in the Outer Continental Shelf in the Gulf of Mexico for the development of oil resources and receives royalties on the oil produced. Conventional methods of oil recovery have recovered or are expected to recover about half of the 16 billion barrels of oil discovered in this area. Other oil recovery methods, collectively known as enhanced oil recovery (EOR), could potentially increase production by about 1 billion barrels of oil. EOR in the Gulf is expensive and does not appear to be economically justified in most cases. Under existing economic conditions and federal policies, GAO's review indicates that utilizing EOR methods will probably produce only about 10 percent of the additional recoverable oil. However, financial incentives in the form of royalty reductions could increase both oil production and federal government revenue if applied on a project-by-project basis. Universal applications of royalty reduction for EOR, however, while achieving increased oil production, would not increase federal government revenue. GAO recommends that the Department of the Interior's Minerals Management Service initiate action that would allow for selective royalty reductions for EOR projects in the Gulf in instances where both total oil production and federal government revenue will increase. 6 figs., 1 tab.

  8. High organic loading rate on thermophilic hydrogen production and metagenomic study at an anaerobic packed-bed reactor treating a residual liquid stream of a Brazilian biorefinery.

    Science.gov (United States)

    Ferraz Júnior, Antônio Djalma Nunes; Etchebehere, Claudia; Zaiat, Marcelo

    2015-06-01

    This study evaluated the influence of a high organic loading rate (OLR) on thermophilic hydrogen production at an up-flow anaerobic packed-bed reactor (APBR) treating a residual liquid stream of a Brazilian biorefinery. The APBR, filled with low-density polyethylene, was operated at an OLR of 84.2 kg-COD m(-3) d(-1). This value was determined in a previous study. The maximum values of hydrogen production and yield were 5,252.6 mL-H2 d(-1) and 3.7 mol-H2 mol(-1)(total carbohydrates), respectively. However, whereas the OLR remained constant, the specific organic load rate (sOLR) decreased throughout operation from 1.38 to 0.72 g-Total carbohydratesg-VS(-1) h(-1), this decrease negatively affected hydrogen production. A sOLR of 0.98 g-Total carbohydratesg-VS(-1) h(-1) was optimal for hydrogen production. The microbial community was studied using 454-pyrosequencing analysis. Organisms belonging to the genera Caloramator, Clostridium, Megasphaera, Oxobacter, Thermoanaerobacterium, and Thermohydrogenium were detected in samples taken from the reactor at operation days 30 and 60, suggesting that these organisms contribute to hydrogen production.

  9. The infrared light curve of Periodic Comet Halley 1986 III and its relationship to the visual light curve, C2, and water production rates

    Science.gov (United States)

    Morris, Charles S.; Hanner, Martha S.

    1993-01-01

    The near-IR light curve of Periodic Comet Halley 1986 III is analyzed and compared with C2 production, water production, and the visual light curve. This is the most complete IR light curve compiled to date for any comet. The scattering phase function at small sun-comet-earth angles is shown to affect the slope of near-IR light curve significantly. P/Halley's dust production, as inferred from the IR light curve showed an increased production rate near perihelion which appears to be correlated with the onset of significant jet activity. The near-IR light curve, visual light curve, C2, and water production rates displayed different heliocentric variations, suggesting that one parameter cannot be accurately estimated from another. This is particularly true of the early preperihelion visual light curve. A peak of 0.3-0.5 magnitude in the visual magnitude, representing the integrated brightness of the comet's visible coma, lagged the other parameters by about a day. The near-IR color, J-H, was less red during periods of strong dust activity.

  10. Co-digestion of molasses or kitchen waste with high-rate activated sludge results in a diverse microbial community with stable methane production.

    Science.gov (United States)

    De Vrieze, Jo; Plovie, Kristof; Verstraete, Willy; Boon, Nico

    2015-04-01

    Kitchen waste and molasses are organic waste streams with high organic content, and therefore are interesting substrates for renewable energy production by means of anaerobic digestion. Both substrates, however, often cause inhibition of the anaerobic digestion process, when treated separately, hence, co-digestion with other substrates is required to ensure stable methane production. In this research, A-sludge (sludge harvested from a high rate activated sludge system) was used to stabilize co-digestion with kitchen waste or molasses. Lab-scale digesters were fed with A-sludge and kitchen waste or molasses for a total period of 105 days. Increased methane production values revealed a stabilizing effect of concentrated A-sludge on kitchen waste digestion. Co-digestion of molasses with A-sludge also resulted in a higher methane production. Volumetric methane production rates up to 1.53 L L(-1) d(-1) for kitchen waste and 1.01 L L(-1) d(-1) for molasses were obtained by co-digestion with A-sludge. The stabilizing effect of A-sludge was attributed to its capacity to supplement various nutrients. Microbial community results demonstrated that both reactor conditions and substrate composition determined the nature of the bacterial community, although there was no direct influence of micro-organisms in the substrate itself, while the methanogenic community profile remained constant as long as optimal conditions were maintained.

  11. The application of an innovative continuous multiple tube reactor as a strategy to control the specific organic loading rate for biohydrogen production by dark fermentation.

    Science.gov (United States)

    Gomes, Simone D; Fuess, Lucas T; Penteado, Eduardo D; Lucas, Shaiane D M; Gotardo, Jackeline T; Zaiat, Marcelo

    2015-12-01

    Biohydrogen production in fixed-bed reactors often leads to unstable and decreasing patterns because the excessive accumulation of biomass in the bed negatively affects the specific organic loading rate (SOLR) applied to the reactor. In this context, an innovative reactor configuration, i.e., the continuous multiple tube reactor (CMTR), was assessed in an attempt to better control the SOLR for biohydrogen production. The CMTR provides a continuous discharge of biomass, preventing the accumulation of solids in the long-term. Sucrose was used as the carbon source and mesophilic temperature conditions (25°C) were applied in three continuous assays. The reactor showed better performance when support material was placed in the outlet chamber to enhance biomass retention within the reactor. Although the SOLR could not be effectively controlled, reaching values usually higher than 10gsucroseg(-1)VSSd(-1), the volumetric hydrogen production and molar hydrogen production rates peaked, respectively, at 1470mLH2L(-1)d(-1) and 45mmolH2d(-1), indicating that the CMTR was a suitable configuration for biohydrogen production.

  12. Effects of starch loading rate on performance of combined fed-batch fermentation of ground wheat for bio-hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Ozmihci, Serpil; Kargi, Fikret [Department of Environmental Engineering, Dokuz Eylul University, 35160 Buca, Izmir (Turkey)

    2010-02-15

    Ground wheat powder solution (10 g L{sup -1}) was subjected to combined dark and light fermentations for bio-hydrogen production by fed-batch operation. A mixture of heat treated anaerobic sludge (AN) and Rhodobacter sphaeroides-NRRL (RS-NRRL) were used as the mixed culture of dark and light fermentation bacteria with an initial dark/light biomass ratio of 1/2. Effects of wheat starch loading rate on the rate and yield of bio-hydrogen formation were investigated. The highest cumulative hydrogen formation (CHF = 3460 ml), hydrogen yield (201 ml H{sub 2} g{sup -1} starch) and formation rate (18.1 ml h{sup -1}) were obtained with a starch loading rate of 80.4 mg S h{sup -1}. Complete starch hydrolysis and glucose fermentation were achieved within 96 h of fed-batch operation producing volatile fatty acids (VFA) and H{sub 2}. Fermentation of VFAs by photo-fermentation for bio-hydrogen production was most effective at starch loading rate of 80.4 mg S h{sup -1}. Hydrogen formation by combined fermentation took place by a fast dark fermentation followed by a rather slow light fermentation after a lag period. (author)

  13. [Effects of lead stress on net photosynthetic rate, SPAD value and ginsenoside production in Ginseng (Panax ginseng)].

    Science.gov (United States)

    Liang, Yao; Jiang, Xiao-Li; Yang, Fen-Tuan; Cao, Qing-Jun; Li, Gang

    2014-08-01

    The paper aimed to evaluate the effects of lead stress on photosynthetic performance and ginsenoside content in ginseng (Panax ginseng). To accomplish this, three years old ginseng were cultivated in pot and in phytotron with different concentrations of lead, ranging from 0 to 1000 mg x kg(-1) soil for a whole growth period (about 150 days). The photosynthetic parameters in leaves and ginsenoside content in roots of ginseng were determined in green fruit stage and before withering stage, respectively. In comparison with the control, net photosynthetic rate and SPAD value in ginseng leaves cultivated with 100 and 250 mg x kg(-1) of lead changed insignificantly, however, ginseng supplied with 500 and 1 000 mg x kg(-1) of lead showed a noticeably decline in the net rate of photosynthesis and SPAD value (P photosynthetic rate and SPAD value showed in the treatment supplied with 1 000 mg x kg(-1) of lead, with decline of 57.8%,11.0%, respectively. Total content of ginsenoside in ginseng roots cultivated with 100 mg x kg(-1) of lead showed insignificantly change compared to the control, but the content increased remarkably in treatments supplied with 250, 500, 1 000 mg x kg(-1) of lead (P photosynthetic rate and SPAD value in leaves of ginseng both showed significantly negative linear correlations with lead stress level (P photosynthetic performance in ginseng leaves, but benefits for accumulation of secondary metabolism (total content of ginsenoside) in ginseng root.

  14. High precipitation rate in a Middle Triassic carbonate platform: Implications on the relationship between seawater saturation state and carbonate production

    Science.gov (United States)

    Franceschi, Marco; Preto, Nereo; Marangon, Alessandro; Gattolin, Giovanni; Meda, Marco

    2016-06-01

    Three-dimensional geological modeling of the Middle Triassic Latemar carbonate platform is coupled with facies modal analysis to estimate its carbonate precipitation rate (G). The 3D model, strongly constrained by field data, encompasses a specific stratigraphic interval of the platform, bounded by two isochronous surfaces. Modal analysis of thin sections allows estimating the proportion of syndepositional vs postdepositional carbonate in the facies associations of the platform. This, together with the 3D facies distribution in the model that takes into account lateral and vertical facies variability, permits to calculate the volumes of syndepositional carbonate preserved at Latemar between the two considered isochrones. Given the peculiar characteristics of the platform, that does not show evidences of strong dissolution processes or large carbonate mass loss through export in the nearby basins, results can be used to estimate the average precipitation rate of the platform in the considered time interval. This estimate allows discussion in relation to models of ocean water saturation state (Ω) with respect to carbonates in the geological past, and comparison to the calculated precipitation rates of modern tropical coral reef ecosystems at global and reef scale. A high G value is found at Latemar and represents the first empirical confirmation that, in the Triassic, extremes in Ω may have triggered high carbonate precipitation in shallow water settings; moreover, comparison to modern reefs points to a possible common relationship that may link seawater Ω and precipitation rate in carbonate platform ecosystems through geological time.

  15. The Impact of Complexity, Rate of Change and Information Availability on the Production Planning and Control Structure

    NARCIS (Netherlands)

    M.F. van Assen (Marcel); S.L. van de Velde (Steef)

    2003-01-01

    textabstractThe organizational theory literature argues that the more uncertain the environment, the more likely the firm’s operational decision structure is decentralized. However, it remains unclear which uncertainty dimensions (i.e. complexity, rate of change and lack of information) impacts the

  16. Increased Success Rates in an FE College: The Product of a Rational or a Performative College Culture?

    Science.gov (United States)

    Boocock, Andrew

    2014-01-01

    Ethnographic research between 2000 and 2005 in the Business Department of a Further Education (FE) college (College X) was designed to uncover the validity of achievement and success rates as proxy measures for the meeting of New Labour's skills and egalitarian agenda. Whilst the general view of senior managers was that improved success rates…

  17. Effect of mixing rate on Beta-carotene production and extraction by dunaliella salina in two-phase bioreactors

    NARCIS (Netherlands)

    Hejazi, M.; Andrysiewicz, E.; Tramper, J.; Wijffels, R.H.

    2003-01-01

    beta-Carotene has many applications in the food, cosmetic, and pharmaceutical industries; Dunaliella salina is currently the main source for natural beta-carotene. We have investigated the effect of mixing rate and whether it leads to the facilitated release of beta-carotene from the cells of Dunali

  18. Daily rhythms in renal blood flow and urine production rate in the near-term sheep fetus

    NARCIS (Netherlands)

    Poortinga, FMI; Aarnoudse, JG

    2000-01-01

    Daily rhythmicity of renal blood flow (RBF) and urine flow (UF) was studied in fetal sheep between 121-125 d of gestation. Fetal arterial blood pressure, heart rate, UF, and right RBF were measured continuously for 24-h periods in 10 sheep, Rhythmic variations during a 24-h period were found for all

  19. Production, oxygen respiration rates, and sinking velocity of copepod fecal pellets: Direct measurements of ballasting by opal and calcite

    DEFF Research Database (Denmark)

    Ploug, H.; Iversen, M.H.; Koski, Marja;

    2008-01-01

    sp., T. weissflogii, and E. huxleyi, respectively. The average carbon-specific respiration rate was 0.15 d(-1) independent on diet (range: 0.08-0.21 d(-1)). Because of ballasting of opal and calcite, sinking velocities were significantly higher for pellets produced on T. weissflogii (322 +/- 169 m d...

  20. Effects of two different nutrient loads on microalgal production, nutrient removal and photosynthetic efficiency in pilot-scale wastewater high rate algal ponds.

    Science.gov (United States)

    Sutherland, Donna L; Turnbull, Matthew H; Broady, Paul A; Craggs, Rupert J

    2014-12-01

    When wastewater treatment high rate algal ponds (HRAP) are coupled with resource recovery processes, such as biofuel production, short hydraulic retention times (HRTs) are often favoured to increase the microalgal biomass productivity. However, short HRT can result in increased nutrient load to the HRAP which may negatively impact on the performance of the microalgae. This paper investigate the effects of high (NH4-N mean concentration 39.7 ± 17.9 g m(-3)) and moderate ((NH4-N mean concentration 19.9 ± 8.9 g m(-3)) nutrient loads and short HRT on the performance of microalgae with respect to light absorption, photosynthesis, biomass production and nutrient removal in pilot-scale (total volume 8 m(3)) wastewater treatment HRAPs. Microalgal biomass productivity was significantly higher under high nutrient loads, with a 133% and 126% increase in the chlorophyll-a and VSS areal productivities, respectively. Microalgae were more efficient at assimilating NH4-N from the wastewater under higher nutrient loads compared to moderate loads. Higher microalgal biomass with increased nutrient load resulted in increased light attenuation in the HRAP and lower light absorption efficiency by the microalgae. High nutrient loads also resulted in improved photosynthetic performance with significantly higher maximum rates of electron transport, oxygen production and quantum yield. This experiment demonstrated that microalgal productivity and nutrient removal efficiency were not inhibited by high nutrient loads, however, higher loads resulted in lower water quality in effluent discharge.

  1. Primary production and carbon export rates across the subpolar N. Atlantic Ocean basin based on triple oxygen isotope and dissolved O2 and Ar gas measurements

    Science.gov (United States)

    Quay, P.; Stutsman, J.; Steinhoff, T.

    2012-06-01

    Gross photosynthetic O2 production (GOP) rates in the subpolar North Atlantic Ocean were estimated using the measured isotopic composition of dissolved oxygen in the surface layer on samples collected on nine transits of a container ship between Great Britain and Canada during March 2007 to June 2008. The mean basin-wide GOP rate of 226 ± 48 mmol O2 m-2 d-1 during summer was double the winter rate of 107 ± 41 mmol O2 m-2 d-1. Converting these GOP rates to equivalent 14C-based PP (14C-PPeqv) yielded rates of 1005 ± 216 and 476 ± 183 mg C m-2 d-1 in summer and winter, respectively, that generally agreed well with previous 14C-based PP estimates in the region. The 14C-PPeqv estimates were 1-1.6× concurrent satellite-based PP estimates along the cruise track. A net community production rate (NCP) of 87 ± 12 mmol O2 m-2 d-1 (62 ± 9 mmol C m-2 d-1) and NCP/GOP of 0.35 ± 0.06 in the mixed layer was estimated from O2/Ar and 17Δ measurements (61°N 26°W) during spring bloom conditions in May 2008. Contrastingly, a much lower long-term annual mean NCP or organic carbon export rate of 2.8 ± 2.7 mol C m-2 yr-1 (8 ± 7 mmol C m-2 d-1) and NCP/GOP of 0.07 ± 0.06 at the winter mixed layer depth was estimated from 15 years of surface O2 data in the subpolar N. Atlantic collected during the CARINA program.

  2. Modelling Chemical Kinetics of Soybean Oil Transesterification Process for Biodiesel Production: An Analysis of Molar Ratio between Alcohol and Soybean Oil Temperature Changes on the Process Conversion Rate

    Directory of Open Access Journals (Sweden)

    Maicon Tait

    2006-12-01

    Full Text Available A mathematical model describing chemical kinetics of transesterification of soybean oil for biodiesel production has been developed. The model is based on the reverse mechanism of transesterification reactions and describes dynamics concentration changes of triglycerides, diglycerides, monoglycerides, biodiesel, and glycerol production. Reaction rate constants were written in the Arrhenius form. An analysis of key process variables such as temperature and molar ratio soybean oil- alcohol using response surface analysis was performed to achieve the maximum soybean conversion rate to biodiesel. The predictive power of the developed model was checked for the very wide range of operational conditions and parameters values by fitting different experimental results for homogeneous catalytic and non-catalytic processes published in the literature. A very good correlation between model simulations and experimental data was observed.

  3. Corrosion product identification and relative rates of corrosion of candidate metals in an irradiated air-steam environment

    Energy Technology Data Exchange (ETDEWEB)

    Reed, D.T.; Swayambunathan, V.; Tani, B.S. (Argonne National Lab., IL (USA)); Van Konynenburg, R.A. (Lawrence Livermore National Lab., CA (USA))

    1989-11-03

    Previously reported work by others indicates that dicopper trihydroxide nitrate, Cu{sub 2}NO{sub 3}(OH){sub 3}, forms on copper and copper alloys subjected to irradiated moist air near room temperature. We have performed experiments over a range of temperature and humidity, and have found that this species is formed at temperatures up to at least 150{degree}C if low to intermediate relative humidities are present. At 150{degree}C and 100% relative humidity, only Cu{sub 2}O and CuO were observed. The relative general corrosion rates of the copper materials tested in 1-month experiments at dose rates of 0.7 and 2.0 kGy/h were Cu > 70/30 Cu--Ni > Al-bronze. High-nickel alloy 825 showed no observable corrosion. 29 refs., 4 tabs.

  4. Effects of subthalamic nucleus deep brain stimulation and levodopa on energy production rate and substrate oxidation in Parkinson's disease.

    Science.gov (United States)

    Perlemoine, Caroline; Macia, Frédéric; Tison, François; Coman, Isabelle; Guehl, Dominique; Burbaud, Pierre; Cuny, Emmanuel; Baillet, Laurence; Gin, Henri; Rigalleau, Vincent

    2005-02-01

    Patients with Parkinson's disease (PD) often lose weight, but after subthalamic nucleus deep brain stimulation (STN-DBS), they gain weight. We compared daily energy intake (DEI), resting energy expenditure (REE) and substrate oxidation rates (measured by indirect calorimetry) in nineteen STN-DBS-treated patients (Group S), thirteen others on pharmacologic treatment by levodopa (Group L) and eight control subjects. We also determined the acute effects of STN-DBS and levodopa on REE and substrate oxidation rates. STN-DBS treated patients gained 9.7 (SEM 7.1) kg after surgery, whereas patients on pharmacologic treatment lost 3.8 (SEM 10.0) kg since diagnosis. In STN-DBS-treated patients, REE (-16.5 %; Pweight gain on glycaemia.

  5. A Stringent Limit on the Mass Production Rate of $r$-Process Elements in the Milky Way

    CERN Document Server

    Macias, Phillip

    2016-01-01

    We analyze data from several studies of metal-poor stars in the Milky Way, focusing on both strong (Eu) and weak (Sr) $r$-process elements. Because these elements were injected in an explosion, we calculate the mass swept up when the blast wave first becomes radiative, yielding a lower limit for the dilution of such elements and hence a lower limit on the ejecta mass which is incorporated into the next generation of stars. Our study demonstrates that in order to explain the largest enhancements in [Eu/Fe] observed in stars at low [Fe/H] metallicities, individual $r$-process production events must synthesize a minimum of $10^{-3.5} M_{\\odot}$ of $r$-process material. We also show that if the site of Mg production is the same as that of Eu, individual injection events must synthesize up to $ \\sim 10^{-3} M_{\\odot}$ of $r$-process material. On the other hand, demanding that Sr traces Mg production results in $r$-process masses per event of $\\sim 10^{-5} M_{\\odot}$. This suggests that the astrophysical sites resp...

  6. Using wastewater and high-rate algal ponds for nutrient removal and the production of bioenergy and biofuels.

    Science.gov (United States)

    Batten, David; Beer, Tom; Freischmidt, George; Grant, Tim; Liffman, Kurt; Paterson, David; Priestley, Tony; Rye, Lucas; Threlfall, Greg

    2013-01-01

    This paper projects a positive outcome for large-scale algal biofuel and energy production when wastewater treatment is the primary goal. Such a view arises partly from a recent change in emphasis in wastewater treatment technology, from simply oxidising the organic matter in the waste (i.e. removing the biological oxygen demand) to removing the nutrients - specifically nitrogen and phosphorus - which are the root cause of eutrophication of inland waterways and coastal zones. A growing need for nutrient removal greatly improves the prospects for using new algal ponds in wastewater treatment, since microalgae are particularly efficient in capturing and removing such nutrients. Using a spreadsheet model, four scenarios combining algae biomass production with the making of biodiesel, biogas and other products were assessed for two of Australia's largest wastewater treatment plants. The results showed that super critical water reactors and anaerobic digesters could be attractive pathway options, the latter providing significant savings in greenhouse gas emissions. Combining anaerobic digestion with oil extraction and the internal economies derived from cheap land and recycling of water and nutrients on-site could allow algal oil to be produced for less than US$1 per litre.

  7. Fermentative hydrogen production and bacterial community structure in high-rate anaerobic bioreactors containing silicone-immobilized and self-flocculated sludge.

    Science.gov (United States)

    Wu, Shu-Yii; Hung, Chun-Hsiung; Lin, Chi-Neng; Chen, Hsin-Wei; Lee, An-Sheng; Chang, Jo-Shu

    2006-04-01

    A novel continuously stirred anaerobic bioreactor (CSABR) seeded with silicone-immobilized sludge was developed for high-rate fermentative H2 production using sucrose as the limiting substrate. The CSABR system was operated at a hydraulic retention time (HRT) of 0.5-6 h and an influent sucrose concentration of 10-40 g COD/L. With a high feeding sucrose concentration (i.e., 30-40 g COD/L) and a short HRT (0.5 h), the CSABR reactor produced H2 more efficiently with the highest volumetric rate (VH2) of 15 L/h/L (i.e., 14.7 mol/d/L) and an optimal yield of ca. 3.5 mol H2/mol sucrose. The maximum VH2 value obtained from this work is much higher than any other VH2 values ever documented. Formation of self-flocculated granular sludge occurred during operation at a short HRT. The granule formation is thought to play a pivotal role in the dramatic enhancement of H2 production rate, because it led to more efficient biomass retention. A high biomass concentration of up to 35.4 g VSS/L was achieved even though the reactor was operated at an extremely low HRT (i.e., 0.5 h). In addition to gaining high biomass concentrations, formation of granular sludge also triggered a transition in bacterial community structure, resulting in a nearly twofold increase in the specific H2 production rate. According to denatured-gradient-gel-electrophoresis analysis, operations at a progressively decreasing HRT resulted in a decrease in bacterial population diversity. The culture with the best H2 production performance (at HRT = 0.5 h and sucrose concentration = 30 g COD/L) was eventually dominated by a presumably excellent H2-producing bacterial species identified as Clostridium pasteurianum.

  8. Water production rate of Comet C/2009 P1 (Garradd) throughout the 2011-2012 apparition: Evidence for an icy grain halo

    Science.gov (United States)

    Combi, M. R.; Mäkinen, J. T. T.; Bertaux, J.-L.; Quémerais, E.; Ferron, S.; Fougere, N.

    2013-07-01

    The all-sky hydrogen Lyman-alpha camera, SWAN (Solar Wind Anisotropies), on the SOlar and Heliospheric Observatory (SOHO) satellite made observations of the hydrogen coma of Comet C/2009 P1 (Garradd) throughout its apparition from August 15, 2011 through April 6, 2012. SOHO has been operating in a halo orbit around the Earth-Sun L1 Lagrange point since its launch in late 1995. Most water vapor produced by the comet is ultimately photodissociated into two H atoms and one O atom producing a huge atomic hydrogen coma that is routinely observed in the daily full-sky SWAN images in comets of sufficient brightness. Water production rates were calculated from 117 images over 8 months of the apparition yielding about 1 observation every 2 days on the average. The activity during much of the pre-perihelion leg was much larger than the post-perihelion leg and varied rather irregularly, not following the more typical steadily increasing trend with decreasing heliocentric distance. It varied generally between 1 and 3 × 1029 s-1, with a peak value of 4 × 1029 s-1 on November 3, 2011, 50 days before perihelion. The elevated production rate from the very large SWAN field-of-view compared with smaller aperture observations could be consistent with water production from icy particles rather than from gas sublimated directly from the nucleus. Scenarios for the nature and production of the icy grain source are explored. During the post-perihelion leg the water production rate decreased more uniformly and typically from 2 × 1029 s-1 at perihelion, approximately as r-3.2, where r is the heliocentric distance. This is consistent with water sublimation from a reasonably constant total surface area.

  9. An Investigation of the Kinematic and Microphysical Control of Lightning Rate, Extent and NOx Production using DC3 Observations and the NASA Lightning Nitrogen Oxides Model (LNOM)

    Science.gov (United States)

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

    2013-01-01

    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

  10. The Role of a Dipeptide Outer-Coordination Sphere on H2 -Production Catalysts: Influence on Catalytic Rates and Electron Transfer

    Energy Technology Data Exchange (ETDEWEB)

    Reback, Matthew L.; Ginovska-Pangovska, Bojana; Ho, Ming-Hsun; Jain, Avijita; Squier, Thomas C.; Raugei, Simone; Roberts, John A.; Shaw, Wendy J.

    2013-02-04

    The outer-coordination sphere of enzymes acts to fine-tune the active site reactivity and control catalytic rates, suggesting that incorporation of analogous structural elements into molecular catalysts may be necessary to achieve rates comparable to those observed in enzyme systems at low overpotentials. In this work, we evaluate the effect of an amino acid and dipeptide outer-coordination sphere on [Ni(PPh2NPh-R2)2]2+ hydrogen production catalysts. A series of 12 new complexes containing non-natural amino acids or dipeptides were prepared to test the effects of positioning, size, polarity and aromaticity on catalytic activity. The non-natural amino acid was either 3-(meta- or para-aminophenyl)propionic acid terminated as an acid, an ester or an amide. Dipeptides consisted of one of the non-natural amino acids coupled to one of four amino acid esters: alanine, serine, phenylalanine or tyrosine. All of the catalysts are active for hydrogen production, with rates averaging ~1000 s-1, 40% faster than the unmodified catalyst. Structure and polarity of the aliphatic or aromatic side chains of the C-terminal peptide do not strongly influence rates. However, the presence of an amide bond increases rates, suggesting a role for the amide in assisting catalysis. Overpotentials were lower with substituents at the N-phenyl meta position. This is consistent with slower electron transfer in the less compact, para-substituted complexes, as shown in digital simulations of catalyst cyclic voltammograms and computational modeling of the complexes. Combining the current results with insights from previous results, we propose a mechanism for the role of the amino acid and dipeptide based outer-coordination sphere in molecular hydrogen production catalysts.

  11. / production

    Indian Academy of Sciences (India)

    François Arleo; Pol-Bernard Gossiaux; Thierry Gousset; Jörg Aichelin

    2003-04-01

    For more than 25 years /Ψ production has helped to sharpen our understanding of QCD. In proton induced reaction some observations are rather well understood while others are still unclear. The current status of the theory of /Ψ production will be sketched, paying special attention to the issues of formation time and /Ψ re-interaction in a nuclear medium.

  12. Modeling of photosynthesis and respiration rate for Isochrysis galbana (T-Iso) and its influence on the production of this strain.

    Science.gov (United States)

    Ippoliti, Davide; Gómez, Cintia; del Mar Morales-Amaral, María; Pistocchi, Rossella; Fernández-Sevilla, J M; Acién, F Gabriel

    2016-03-01

    Isochrysis galbana is a widely-used strain in aquaculture in spite of its low productivity. To maximize the productivity of processes based on this microalgae strain, we have developed a model considering the influence of irradiance, temperature, pH and dissolved oxygen concentration on the photosynthesis and respiration rate. Results demonstrate that this strain tolerates temperatures up to 35 °C but it is highly sensitive to irradiances higher than 500 μE m(-2)s(-1) and dissolved oxygen concentrations higher than 11 mgl(-1). We have validated the developed model using data from an industrial-scale outdoor tubular photobioreactor demonstrating that inadequate temperature and dissolved oxygen concentrations reduce productivity to half that which is maximal, according to light availability under real outdoor conditions. The developed model is a useful tool for managing working processes, but especially in the development of new processes based on this strain and to take decisions regarding optimal control strategies.

  13. Emission Rates of Volatile Organic Compounds Released from Newly Produced Household Furniture Products Using a Large-Scale Chamber Testing Method

    Directory of Open Access Journals (Sweden)

    Duy Xuan Ho

    2011-01-01

    Full Text Available The emission rates of volatile organic compounds (VOCs were measured to investigate the emission characteristics of five types of common furniture products using a 5 m3 size chamber at 25°C and 50% humidity. The results indicated that toluene and α-pinene are the most dominant components. The emission rates of individual components decreased constantly through time, approaching the equilibrium emission level. The relative ordering of their emission rates, if assessed in terms of total VOC (TVOC, can be arranged as follows: dining table > sofa > desk chair > bedside table > cabinet. If the emission rates of VOCs are examined between different chemical groups, they can also be arranged in the following order: aromatic (AR > terpenes (TER > carbonyl (CBN > others > paraffin (PR > olefin (HOL > halogenated paraffin (HPR. In addition, if emission strengths are compared between coated and uncoated furniture, there is no significant difference in terms of emission magnitude. Our results indicate that the emission characteristics of VOC are greatly distinguished between different furniture products in terms of relative dominance between different chemicals.

  14. Hydrogen Production with High Evolution Rate and High Yield by Immobilized Cells of Hydrogen-producing Bacteria Strain B49 in a Column Reactor

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To improve the hydrogen evolution rate in continuous hydrogen production of a novel fermentative hydrogen-producing bacteria strain B49 (AF481148 in EMBL), 4 % immobilized cells by polyvinyl alcohol-boric acid method, with the addition of a small amount of calcium alginate in a column reactor obtain hydrogen yield of 2.31 mol H2/mol glucose and hydrogen evolution rate of 1435.4 ml/L culture*h respectively at medium retention time of 2.0 h with a medium containing 10g glucose/L. Moreover, as the cell density in gel beads is increased to 8%, hydrogen yield and hydrogen evolution rate for 10g glucose/L are 2.34 mol H2/mol glucose and 2912.4 ml/L culture*h respectively at medium retention time of 1.0 h, and for molasses wastewater COD of 7505.9 mg/L hydrogen production potential of 205.6 ml/g COD and hydrogen evolution rate of 2057.7 ml/L culture*h at hydraulic retention time of 0.75 h are observed. In the continuous culture pH value keeps around 3.9 by self-regulating.

  15. Continuous fermentation and in-situ reed separation of butyric acid for higher sugar consumption rate and productivity

    DEFF Research Database (Denmark)

    Baroi, George Nabin; Skiadas, Ioannis; Westermann, Peter;

    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......) and resulted in a butyric acid productivity and yield of 1.31g/L/h and 0.44 g/g, respectively at 1 day HRT. Acknowledgements: This work is a part of EU-7th Framework programme supported project SUPRABIO (FP7-cooperationproject no 241640)....

  16. Measurement of the B$^{0}_{s}$ lifetime and production rate with D$^{-}_{s}$ l$^{+}$ combinations in Z decays

    CERN Document Server

    Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Garrido, L; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Meinhard, H; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Stierlin, U; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Duarte, H; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Rosowsky, A; Roussarie, A; Schuller, J P; Schwindling, J; Si Mohand, D; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1995-01-01

    The lifetime of the \\bs meson is measured in approximately 3 million hadronic Z decays accumulated using the ALEPH detector at LEP from 1991 to 1994. Seven different \\ds decay modes were reconstructed and combined with an opposite sign lepton as evidence of semileptonic \\bs decays. Two hundred and eight \\dsl candidates satisfy selection criteria designed to ensure precise proper time reconstruction and yield a measured \\bs lifetime of \\mbox{\\result .} Using a larger, less constrained sample of events, the product branching ratio is measured to be \\mbox{\\pbrresult .

  17. Production of bovine cloned embryos with donor cells frozen at a slow cooling rate in a conventional freezer (20 C)

    Science.gov (United States)

    Chacon, L.; Gomez, M.C.; Jenkins, J.A.; Leibo, S.P.; Wirtu, G.; Dresser, B.L.; Pope, C.E.

    2009-01-01

    Summary Usually, fibroblasts are frozen in dimethyl sulphoxide (DMSO, 10% v/v) at a cooling rate of 1 C/min in a low-temperature (80 C) freezer (LTF) before storage in liquid nitrogen (LN2); however, a LTF is not always available. The purpose of the present study was to evaluate apoptosis and viability of bovine fibroblasts frozen in a LTF or conventional freezer (CF; 20 C) and their subsequent ability for development to blastocyst stage after fusion with enucleated bovine oocytes. Percentages of live cells frozen in LTF (49.5%) and CF (50.6%) were similar, but significantly less than non-frozen control (88%). In both CF and LTF, percentages of live apoptotic cells exposed to LN2 after freezing were lower (4% and 5%, respectively) as compared with unexposed cells (10% and 18%, respectively). Cells frozen in a CF had fewer cell doublings/24 h (0.45) and required more days (9.1) to reach 100% confluence at the first passage (P) after thawing and plating as compared with cells frozen in a LTF (0.96 and 4.0 days, respectively). Hypoploidy at P12 was higher than at P4 in cells frozen in either a CF (37.5% vs. 19.2%) or in a LTF (30.0% vs. 15.4%). A second-generation cryo-solution reduced the incidence of necrosis (29.4%) at 0 h after thawing as compared with that of a first generation cryo-solution (DMEM + DMSO, 60.2%). The percentage of apoptosis in live cells was affected by cooling rate (CF = 1.9% vs. LFT = 0.7%). Development of bovine cloned embryos to the blastocyst stage was not affected by cooling rate or freezer type. ?? 2009 Cambridge University Press.

  18. A Compact, Transportable, Microchip-Based System for High Repetition Rate Production of Bose-Einstein Condensates

    CERN Document Server

    Farkas, Daniel M; Salim, Evan A; Segal, Stephen R; Squires, Matthew B; Anderson, Dana Z

    2009-01-01

    We present a compact, transportable system that produces Bose-Einstein condensates (BECs) near the surface of an integrated atom microchip. The system occupies a volume of 0.4 m^3 and operates at a repetition rate as high as 0.3 Hz. Evaporative cooling in a chip trap with trap frequencies of several kHz leads to nearly pure condensates containing 1.9x10^4 87Rb atoms. Partial condensates are observed at a temperature of 1.58(8) \\mu K, close to the theoretical transition temperature of 1.1 \\mu K.

  19. The effects of outdoor air supply rate in an office on perceived air quality, sick building syndrome (SBS) symptoms and productivity.

    Science.gov (United States)

    Wargocki, P; Wyon, D P; Sundell, J; Clausen, G; Fanger, P O

    2000-12-01

    Perceived air quality, Sick Building Syndrome (SBS) symptoms and productivity were studied in a normally furnished office space (108 m3) ventilated with an outdoor airflow of 3, 10 or 30 L/s per person, corresponding to an air change rate of 0.6, 2 or 6 h-1. The temperature of 22 degrees C, the relative humidity of 40% and all other environmental parameters remained unchanged. Five groups of six female subjects were each exposed to the three ventilation rates, one group and one ventilation rate at a time. Each exposure lasted 4.6 h and took place in the afternoon. Subjects were unaware of the intervention and remained thermally neutral by adjusting their clothing. They assessed perceived air quality and SBS symptoms at intervals, and performed simulated normal office work. Increasing ventilation decreased the percentage of subjects dissatisfied with the air quality (P < 0.002) and the intensity of odour (P < 0.02), and increased the perceived freshness of air (P < 0.05). It also decreased the sensation of dryness of mouth and throat (P < 0.0006), eased difficulty in thinking clearly (P < 0.001) and made subjects feel generally better (P < 0.0001). The performance of four simulated office tasks improved monotonically with increasing ventilation rates, and the effect reached formal significance in the case of text-typing (P < 0.03). For each two-fold increase in ventilation rate, performance improved on average by 1.7%. This study shows the benefits for health, comfort and productivity of ventilation at rates well above the minimum levels prescribed in existing standards and guidelines. It confirms the results of a previous study in the same office when the indoor air quality was improved by decreasing the pollution load while the ventilation remained unchanged.

  20. Playing catch-up with Escherichia coli: Using yeast to increase success rates in recombinant protein production experiments

    Directory of Open Access Journals (Sweden)

    Roslyn Mary Bill

    2014-03-01

    Full Text Available Several host systems are available for the production of recombinant proteins, ranging from Escherichia coli to mammalian cell-lines. This article highlights the benefits of using yeast, especially for more challenging targets such as membrane proteins. On account of the wide range of molecular, genetic and microbiological tools available, use of the well-studied model organism, Saccharomyces cerevisiae, provides many opportunities to optimize the functional yields of a target protein. Despite this wealth of resources, it is surprisingly under-used. In contrast, Pichia pastoris, a relative new-comer as a host organism, is already becoming a popular choice, particularly because of the ease with which high biomass (and hence recombinant protein yields can be achieved. In the last few years, advances have been made in understanding how a yeast cell responds to the stress of producing a recombinant protein and how this information can be used to identify improved host strains in order to increase functional yields. Given these advantages, and their industrial importance in the production of biopharmaceuticals, I argue that S. cerevisiae and P. pastoris should be considered at an early stage in any serious strategy to produce proteins