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Sample records for burnup determination based

  1. Chemical burnup determination based on spectrophotometric measurement of total rare earth fission products, uranium, and plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, S.F.; Ortiz, M.R.; Rein, J.E.

    1975-10-01

    A chemical burnup procedure incorporates the ion-exchange separation of uranium, plutonium, and total rare earth fission products (as the fission monitor) followed by the spectrophotometric determination of each. The separation involves retaining uranyl and plutonyl chloride complexes on a macroporous anion exchange column from 12 M HCl, whereas the rare earths and most fission products pass through. Subsequently, plutonium is eluted with 0.1 M HI-12 M HCl and uranium with 0.1 M HCl. From the initial effluent of the first column, the rare earth group is separated on a second column of either (1) macroporous anion exchange resin from HNO/sub 3/-CH/sub 3/OH, or (2) pellicular cation exchange particles from HCl-C/sub 2/H/sub 5/OH. The HNO/sub 3/--CH/sub 3/OH system normally is used to separate the rare earth group from fuel cladding elements and other fission products. The HCl--C/sub 2/H/sub 5/OH system additionally separates the rare earth group from americium. Arsenazo III is the chromogenic agent for the spectrophotometric determination of the separated uranium, plutonium, and rare earth fractions.

  2. Automated system for determining the burnup of spent nuclear fuel

    Directory of Open Access Journals (Sweden)

    Mokritskii V. A.

    2014-12-01

    Full Text Available The authors analyze their experience in application of semi-conductor detectors and development of a breadboard model of the monitoring system for spent nuclear fuel (SNF. Such system should use CdZnTe-detectors in which one-charging gathering conditions are realized. The proposed technique of real time SNF control during reloading technological operations is based on the obtained research results. Methods for determining the burnup of spent nuclear fuel based on measuring the characteristics of intrinsic radiation are covered in many papers, but those metods do not usually take into account that the nuclear fuel used during the operation has varying degrees of initial enrichment, or a new kind of fuel may be used. Besides, the known methods often do not fit well into the existing technology of fuel loading operations and are not suitable for operational control. Nuclear fuel monitoring (including burnup determination system in this research is based on the measurement of the spectrum of natural gamma-radiation of irradiated fuel assemblies (IFA, as from the point of view of minimizing the time spent, the measurement of IFA gamma spectra directly during fuel loading is optimal. It is the overload time that is regulated rather strictly, and burnup control operations should be coordinated with the schedule of the fuel loading. Therefore, the real time working capacity of the system should be chosen as the basic criterion when constructing the structure of such burnup control systems.

  3. An iterative approach for TRIGA fuel burn-up determination using nondestructive gamma-ray spectrometry.

    Science.gov (United States)

    Wang, T K; Peir, J J

    2000-01-01

    The purpose of this work is to establish a method for evaluating the burn-up values of the rod-type TRIGA spent fuel by using gamma-ray spectrometry of the short-lived fission products 97Zr/97Nb, 132I, and 140La. Fuel irradiation history is not needed in this method. Short-lived fission-product activities were established by reirradiating the spent fuels in a nuclear reactor. Based on the measured activities, 235U burn-up values can be deduced by iterative calculations. The complication caused by 239Pu production and fission is also discussed in detail. The burn-up values obtained by this method are in good agreement with those deduced from the conventional method based on long-lived fission products 137Cs, 134Cs/137Cs ratio and 106Ru/137Cs ratio.

  4. A feasibility and optimization study to determine cooling time and burnup of advanced test reactor fuels using a nondestructive technique

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    Navarro, Jorge [Univ. of Utah, Salt Lake City, UT (United States)

    2013-12-01

    The goal of this study presented is to determine the best available non-destructive technique necessary to collect validation data as well as to determine burn-up and cooling time of the fuel elements onsite at the Advanced Test Reactor (ATR) canal. This study makes a recommendation of the viability of implementing a permanent fuel scanning system at the ATR canal and leads3 to the full design of a permanent fuel scan system. The study consisted at first in determining if it was possible and which equipment was necessary to collect useful spectra from ATR fuel elements at the canal adjacent to the reactor. Once it was establish that useful spectra can be obtained at the ATR canal the next step was to determine which detector and which configuration was better suited to predict burnup and cooling time of fuel elements non-destructively. Three different detectors of High Purity Germanium (HPGe), Lanthanum Bromide (LaBr3), and High Pressure Xenon (HPXe) in two system configurations of above and below the water pool were used during the study. The data collected and analyzed was used to create burnup and cooling time calibration prediction curves for ATR fuel. The next stage of the study was to determine which of the three detectors tested was better suited for the permanent system. From spectra taken and the calibration curves obtained, it was determined that although the HPGe detector yielded better results, a detector that could better withstand the harsh environment of the ATR canal was needed. The in-situ nature of the measurements required a rugged fuel scanning system, low in maintenance and easy to control system. Based on the ATR canal feasibility measurements and calibration results it was determined that the LaBr3 detector was the best alternative for canal in-situ measurements; however in order to enhance the quality of the spectra collected using this scintillator a deconvolution method was developed. Following the development of the deconvolution method

  5. A Simple Formula for Local Burnup and Isotope Distributions Based on Approximately Constant Relative Reaction Rate

    Directory of Open Access Journals (Sweden)

    Cenxi Yuan

    2016-01-01

    Full Text Available A simple and analytical formula is suggested to solve the problems of the local burnup and the isotope distributions. The present method considers two extreme conditions of neutrons penetrating the fuel rod. Based on these considerations, the formula is obtained to calculate the reaction rates of 235U, 238U, and 239Pu and straightforward the local burnup and the isotope distributions. Starting from an initial burnup level, the parameters of the formula are fitted to the reaction rates given by a Monte Carlo (MC calculation. Then the present formula independently gives very similar results to the MC calculation from the starting to high burnup level but takes just a few minutes. The relative reaction rates are found to be almost independent of the radius (except (n,γ of  238U and the burnup, providing a solid background for the present formula. A more realistic examination is also performed when the fuel rods locate in an assembly. A combination of the present formula and the MC calculation is expected to have a nice balance between the numerical accuracy and time consumption.

  6. Development of a method for xenon determination in the microstructure of high burn-up nuclear fuel[Dissertation 17527

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, M. I

    2008-07-01

    In nuclear fuel, in approximately one quarter of the fissions, one of the two formed fission products is gaseous. These are mainly the noble gases xenon and krypton with isotopes of xenon contributing up to 90% of the product gases. These noble fission gases do not combine with other species, and have a low solubility in the normally used uranium oxide matrix. They can be dissolved in the fuel matrix or precipitate in nanometer-sized bubbles within the fuel grain, in micrometer-sized bubbles at the grain boundaries, and a fraction also precipitates in fuel pores, coming from fuel fabrication. A fraction of the gas can also be released into the plenum of the fuel rod. With increasing fission, and therefore burn-up, the ceramic fuel material experiences a transformation of its structure in the 'cooler' rim region of the fuel. A subdivision occurs of the original fuel grains of few microns size into thousands of small grains of sub-micron sizes. Additionally, larger pores are formed, which also leads into an increasing porosity in the fuel rim, called high burn-up structure. In this structure, only a small fraction of the fission gas remains in the matrix, the major quantity is said to accumulate in these pores. Because of this accumulation, the knowledge of the quantities of gas within these pores is of major interest in consideration to burn-up, fuel performance and especially for safety issues. In case of design based accidents, i.e. rapidly increasing temperature transients, the behavior of the fuel has to be estimated. Various analytical techniques have been used to determine the Xe concentration in nuclear fuel samples. The capabilities of EPMA (Electron Probe Micro-Analyser) and SIMS (Secondary Ion Mass Spectrometry) have been studied and provided some qualitative information, which has been used for determining Xe-matrix concentrations. First approaches combining these two techniques to estimate pore pressures have been recently reported. However

  7. Burnup simulations and spent fuel characteristics of ZrO 2 based inert matrix fuels

    Science.gov (United States)

    Schneider, E. A.; Deinert, M. R.; Herring, S. T.; Cady, K. B.

    2007-03-01

    Reducing the inventory of long lived isotopes that are contained in spent nuclear fuel is essential for maximizing repository capacity and extending the lifetime of related storage. Because of their non-fertile matrices, inert matrix fuels (IMF's) could be an ideal vehicle for using light-water reactors to help decrease the inventory of plutonium and other transuranics (neptunium, americium, curium) that are contained within spent uranium oxide fuel (UOX). Quantifying the characteristics of spent IMF is therefore of fundamental importance to determining its effect on repository design and capacity. We consider six ZrO 2 based IMF formulations with different transuranic loadings in a 1-8 IMF to UOX pin-cell arrangement. Burnup calculations are performed using a collision probability model where transport of neutrons through space is modeled using fuel to moderator transport and escape probabilities. The lethargy dependent neutron flux is treated with a high resolution multigroup thermalization method. The results of the reactor physics model are compared to a benchmark case performed with Montebruns and indicate that the approach yields reliable results applicable to high-level analyses of spent fuel isotopics. The data generated show that a fourfold reduction in the radiological and integrated thermal output is achievable in single recycle using IMF, as compared to direct disposal of an energy equivalent spent UOX.

  8. Fuel burnup measurements in FFTF

    Energy Technology Data Exchange (ETDEWEB)

    Rawlins, J.A.; Wootan, D.W.; Dobbin, K.D.

    1984-08-01

    Fuel burnup and isotopic fission rates were measured in FFTF during acceptance testing in an 8.6 day full power irradiation. Results were compared with three-dimensional diffusion theory calculations based on ENDF/B-V cross sections. A bias of about 3% exists between burnup and fission rate data, although measured axial and radial profiles are in good agreement. The calculated and measured radial power distributions are in disagreement by 6 to 10% from core center to the outer row of fuel. At core center, calculation/experiment (C/E) for isotopic fission rates is generally 1.01 while C/E for burnup is 1.04. Overall measurement uncertainties are 3% and 2% for fission rate and burnup experiments, respectively. Application of the results to a long-range goal of calculating burnup to 1% accuracy is discussed.

  9. A Feasibility Study to Determine Cooling Time and Burnup of ATR Fuel Using a Nondestructive Technique and Three Types of Gamma-ray Detectors

    Energy Technology Data Exchange (ETDEWEB)

    Jorge Navarro; Rahmat Aryaeinejad,; David W. Nigg

    2011-05-01

    A Feasibility Study to Determine Cooling Time and Burnup of ATR Fuel Using a Nondestructive Technique1 Rahmat Aryaeinejad, Jorge Navarro, and David W Nigg Idaho National Laboratory Abstract Effective and efficient Advanced Test Reactor (ATR) fuel management require state of the art core modeling tools. These new tools will need isotopic and burnup validation data before they are put into production. To create isotopic, burn up validation libraries and to determine the setup for permanent fuel scanner system a feasibility study was perform. The study consisted in measuring short and long cooling time fuel elements at the ATR canal. Three gamma spectroscopy detectors (HPGe, LaBr3, and HPXe) and two system configurations (above and under water) were used in the feasibility study. The first stage of the study was to investigate which detector and system configuration would be better suited for different scenarios. The second stage of the feasibility study was to create burnup and cooling time calibrations using experimental isotopic data collected and ORIGEN 2.2 burnup data. The results of the study establish that a better spectra resolution is achieve with an above the water configuration and that three detectors can be used in the permanent fuel scanner system for different situations. In addition it was conclude that a number of isotopic ratios and absolute measurements could be used to predict ATR fuel burnup and cooling times. 1This work was supported by the U.S. Depart¬ment of Energy (DOE) under Battelle Energy Alliance, LLC Contract No. DE-AC07-05ID14517.

  10. Study of the triton-burnup process in different JET scenarios using neutron monitor based on CVD diamond

    Energy Technology Data Exchange (ETDEWEB)

    Nemtsev, G., E-mail: g.nemtsev@iterrf.ru; Amosov, V.; Meshchaninov, S.; Rodionov, R. [Institution “Project center ITER,” Moscow (Russian Federation); Popovichev, S. [CCFE, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Collaboration: EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

    2016-11-15

    We present the results of analysis of triton burn-up process using the data from diamond detector. Neutron monitor based on CVD diamond was installed in JET torus hall close to the plasma center. We measure the part of 14 MeV neutrons in scenarios where plasma current varies in a range of 1-3 MA. In this experiment diamond neutron monitor was also able to detect strong gamma bursts produced by runaway electrons arising during the disruptions. We can conclude that CVD diamond detector will contribute to the study of fast particles confinement and help predict the disruption events in future tokamaks.

  11. Burnup Credit of Erbia Super-High-Burnup Fuel

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    Sugimura, Naoki; Imamura, Michitaka; Mori, Masaaki [Nuclear Engineering, Ltd., Osaka (Japan); Yamasaki, Masatoshi [Nuclear Fuel Industries, Ltd., Osaka (Japan)

    2008-07-01

    Based on the concept of the Erbia bearing Super High-Burnup (Er-SHB) fuel, the initial erbia contents to guarantee the lower reactivity than that of the conventional 5.0 wt% enriched UO{sub 2} fuels during burnup and cooling are studied. According to the results, the feasibility of the commercial PWR cores using Er-SHB fuels is verified. As the results, it is verified that the long life core operation using Er-SHB fuel are feasible and approximately 20% of feed fuel assemblies can be saved by using Er-SHB fuel. (authors)

  12. Flexible modified candle burnup scheme based long life Pb-Bi cooled fast reactor with natural uranium as fuel cycle input employing coupled core

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    Su' ud, Zaki; SNM, Rida [Physics Dept., ITB, Jl. Ganesha 10, Bandung, West Java 40132 (Indonesia); Sekimoto, Hiroshi [Tokyo Inst. of Technology (Japan)

    2009-06-15

    calculation is then brought back to SRAC code for cell burn-up calculation. This iteration is repeated until the convergence is reached. Using the coupling dual core concept after some optimization we got several design which can fulfill the criteria can be obtained. Among of the main results are the design of long-life Pb-Bi cooled fast reactors which fuel cycle input is natural uranium but the maximum burnup level can be adjusted from about 10% HM to 40% HM. The results show that the twin(coupling )core concept can work well and give excellent configuration of modified CANDLE with flexible maximum burnup level up which can reach current fast reactors fuel technology. References: 1. H. Sekimoto, Light a CANDLE An Innovative Burnup Strategy of Nuclear Reactors, COE INES, Research Lab. For Nuclear Reactors, Tokyo Institute of Technology, Japan. 2. H. Sekimoto, et al, 'CANDLE: The New Burnup Strategy', Nuclear Science and Engineering, 139, 1-12 (2001), 3. Zaki S and H. Sekimoto: 'Optimization of Modified Candle Burnup Scheme Based Long Life Pb-Bi Cooled Fast Reactor with Natural Uranium as Fuel Cycle Input', PBNC 2008 Conference, Oct. 11-18, 2008, Aomori Japan. 4. Zaki S and H. Sekimoto: 'Design Study Of Long Life Pb-Bi Cooled Fast Reactor With Natural Uranium As Fuel Cycle Input Using Modified Candle Burnup Scheme' Submitted to Annals of Nuclear Energy. (authors)

  13. Determination of Light Water Reactor Fuel Burnup with the Isotope Ratio Method

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J.; Hurley, David E.

    2007-11-01

    For the current project to demonstrate that isotope ratio measurements can be extended to zirconium alloys used in LWR fuel assemblies we report new analyses on irradiated samples obtained from a reactor. Zirconium alloys are used for structural elements of fuel assemblies and for the fuel element cladding. This report covers new measurements done on irradiated and unirradiated zirconium alloys, Unirradiated zircaloy samples serve as reference samples and indicate starting values or natural values for the Ti isotope ratio measured. New measurements of irradiated samples include results for 3 samples provided by AREVA. New results indicate: 1. Titanium isotope ratios were measured again in unirradiated samples to obtain reference or starting values at the same time irradiated samples were analyzed. In particular, 49Ti/48Ti ratios were indistinguishably close to values determined several months earlier and to expected natural values. 2. 49Ti/48Ti ratios were measured in 3 irradiated samples thus far, and demonstrate marked departures from natural or initial ratios, well beyond analytical uncertainty, and the ratios vary with reported fluence values. The irradiated samples appear to have significant surface contamination or radiation damage which required more time for SIMS analyses. 3. Other activated impurity elements still limit the sample size for SIMS analysis of irradiated samples. The sub-samples chosen for SIMS analysis, although smaller than optimal, were still analyzed successfully without violating the conditions of the applicable Radiological Work Permit

  14. Determination of Fission Gas Inclusion Pressures in High Burnup Nuclear Fuel using Laser Ablation ICP-MS combined with SEM/EPMA and Optical Microscopy

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    Horvath, Matthias I.; Guenther-Leopold, Ines; Kivel, Niko; Restani, Renato [Laboratory for Materials Behavior, Nuclear Energy and Safety, Paul Scherrer Institut, Villigen, CH-5232 (Switzerland); Guillong, Marcel [Institute for Isotope Geology/Mineralogic Elements, ETH Zuerich, CH-8092 (Switzerland); Izmer, Andrei [Environmental and Resource Studies, Trent University, Peterborough, K9J 7B8 (Canada); Hellwig, Christian [Nuclear Technology Department, Nordostschweizerische Kraftwerke AG (NOK), Baden, CH-5401 (Switzerland); Guenther, Detlef [Laboratory for Inorganic Chemistry, Trace Elements and Microanalysis Group, ETH Zuerich, CH-8093 (Switzerland)

    2008-07-01

    In approximately 20% of all fissions at least one of the fission products is gaseous. These are mainly xenon and krypton isotopes contributing up to 90% by the xenon isotopes. Upon reaching a burn-up of 60 - 75 GWd/tHM a so called High Burnup Structure (HBS) is formed in the cooler rim of the fuel. In this region a depletion of the noble fission gases (FG) in the matrix and an enrichment of FG in {mu}m-sized pores can be observed. Recent calculations show that in these pores the pressure at room temperature can be as large as 30 MPa. The knowledge of the FG pressure in pores is important to understand the high burn-up fuel behavior under accident conditions (i.e. RIA or LOCA). With analytical methods routinely used for the characterization of solid samples, i.e. Electron Probe Micro Analysis (EPMA), Secondary Ion Mass Spectrometry (SIMS), the quantification of gaseous inclusions is very difficult to almost impossible. The combination of a laser ablation system (LA) with an inductively coupled plasma mass spectrometer (ICP-MS) offers a powerful tool for quantification of the gaseous pore inventory. This method offers the advantages of high spatial resolution with laser spot sizes down to 10 {mu}m and low detection limits. By coupling with scanning electron microscopy (SEM) for the pore size distribution, EPMA for the FG inventory in the fuel matrix and optical microscopy for the LA-crater sizes, the pressures in the pores and porosity was calculated. As a first application of this calibration technique for gases, measurements were performed on pressurized water reactor (PWR) fuel with a rod average of 105 GWd/tHM to determine the local FG pressure distribution. (authors)

  15. The Non-Destructive Determination of Burn-Up by Means of the Pr{sup l44} 2.18 M Gamma Activity

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R.S.; Blackadder, W.H.

    1965-05-15

    In recent years, gamma scanning has been used at several establishments for the determination of the burn-up profile along irradiated fuel elements, the 0.75 MeV gamma from Zr-95/Nb-95 being most often employed as the monitored radiation. Difficulties in establishing the geometry and the self-absorption of the gamma activity in the fuel have tended to prevent the application of the method to quantitative burn-up determination, which has usually been carried out by dissolution of selected portions of the fuel followed by conventional fission product separation or by uranium depletion methods. The present paper describes experiments carried out to calibrate a gamma scanner for quantitative measurements by counting the 2.18 MeV gamma activity due to Pr-144, the short-lived daughter of Ce-144 (t{sub 1/2} = 285 days) from selected pellets in several UO{sub 2} fuel specimens. Accurate burn-up values were then determined by dissolution and application of the isotopic dilution method, using stable molybdenum fission products. The elements, which were rotated about their longitudinal axes to minimize asymmetry effects, were viewed by a sodium iodide crystal and a multichannel analyser through a suitable collimator. Correction for attenuation of the gamma activity (much less than for 0.75 MeV) in the fuel elements which were of different diameters (12.6 to 15.04 mm) was made by applying relative attenuation factors and the effective geometry factor of the instrument was determined. In order to check the corrections applied, the counter factor was also calculated, for the 0.75 MeV activity from Zr-95/Nb-95 and in certain cases for the 0.66 MeV activity from Cs-137. The results obtained, demonstrate that at least over the range of diameters and cooling times used the method is suitable for quantitative determinations. Preliminary experiments to explore the possibility of using the high energy gammas (2.35, 2.65 MeV) from Rh-106 as a method for estimating the fraction of

  16. Direct Measurement of Initial Enrichment and Burn-up of Spent Fuel Assembly with a Differential Die-Away Technique Based Instrument

    Energy Technology Data Exchange (ETDEWEB)

    Henzl, Vladimir [Los Alamos National Laboratory; Swinhoe, Martyn T. [Los Alamos National Laboratory; Tobin, Stephen J. [Los Alamos National Laboratory

    2012-07-16

    A key objective of the Next Generation Safeguards Initiative (NGSI) is to utilize non-destructive assay (NDA) techniques to determine the elemental plutonium (Pu) content in a commercial-grade nuclear spent fuel assembly (SFA). In the third year of the NGSI Spent Fuel NDA project, the research focus is on the integration of a few NDA techniques. One of the reoccurring challenges to the accurate determination of Pu content has been the explicit dependence of the measured signal on the presence of neutron absorbers which build up in the assembly in accordance with its operating and irradiation history. The history of any SFA is often summarized by the parameters of burn-up (BU), initial enrichment (IE) and cooling time (CT). While such parameters can typically be provided by the operator, the ability to directly measure and verify them would significantly enhance the autonomy of the IAEA inspectorate. Within this paper, we demonstrate that an instrument based on a Differential Die-Away technique is in principle capable of direct measurement of IE and, should the CT be known, also the BU.

  17. Dependence of control rod worth on fuel burnup

    Energy Technology Data Exchange (ETDEWEB)

    Savva, P., E-mail: savvapan@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece); Varvayanni, M., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N., E-mail: nicos@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece)

    2011-02-15

    Research highlights: Diffusion and MC calculations for rod worth dependence on burnup and Xe in reactors. One-step rod withdrawal/insertion are used for rod worth estimation. The study showed that when Xe is present the rods worth is significantly reduced. Rod worth variation with burnup depends on rod position in core. Rod worth obtained with MC code is higher than that obtained from deterministic. - Abstract: One important parameter in the design and the analysis of a nuclear reactor core is the reactivity worth of the control rods, i.e. their efficiency to absorb excess reactivity. The control rod worth is affected by parameters such as the fuel burnup in the rod vicinity, the Xe concentration in the core, the operational time of the rod and its position in the core. In the present work, two different computational approaches, a deterministic and a stochastic one, were used for the determination of the rods worth dependence on the fuel burnup level and the Xe concentration level in a conceptual, symmetric reactor core, based on the MTR fuel assemblies used in the Greek Research Reactor (GRR-1). For the deterministic approach the neutronics code system composed by the SCALE modules NITAWL and XSDRN and the diffusion code CITATION was used, while for the stochastic one the Monte Carlo code TRIPOLI was applied. The study showed that when Xe is present in the core, the rods worth is significantly reduced, while the rod worth variation with increasing burnup depends on the rods position in the core grid. The rod worth obtained with the use of the Monte Carlo code is higher than the one obtained from the deterministic code.

  18. Alloy development for high burnup cladding (PWR)

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, R. [Kraftwerk Union AG, Mulheim (Germany); Jeong, Y.H.; Baek, K.H.; Kim, S.J.; Choi, B.K.; Kim, J.M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1999-04-01

    An overview on current alloy development for high burnup PWR fuel cladding is given. It is mainly based on literature data. First, the reasons for an increase of the current mean discharge burnup from 35 MWd / kg(U) to 70 MWd / kg(U) are outlined. From the material data, it is shown that a batch average burnup of 60-70 MWd / kg(U), as aimed by many fuel vendors, can not be achieved with stand (=ASTM-) Zry-4 cladding tubes without violating accepted design criteria. Specifically criteria which limit maximum oxide scale thickness and maximum hydrogen content, and to a less degree, maximum creep and growth rate, can not be achieved. The development potential of standard Zry-4 is shown. Even when taking advantage of this potential, it is shown that an 'improved' Zry-4 is reaching its limits when it achieves the target burnup. The behavior of some Zr alloys outside the ASTM range is shown, and the advantages and disadvantages of the 3 alloy groups (ZrSn+transition metals, ZrNb, ZrSnNb+transition metals) which are currently considered to have the development potential for high burnup cladding materials are depicted. Finally, conclusions are drawn. (author). 14 refs., 11 tabs., 82 figs.

  19. Non-destructive determination of the burn-up of a nuclear fuel using {gamma} spectrometry; Determination non destructive du taux de combustion d'un combustible nucleaire par spectrometrie {gamma}

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    Engelman, Ch.; Petit, J.F. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    A non-destructive method has been developed for measuring the burn-up of a nuclear fuel. The principle of the method is based on the quantitative determination of a fission product using {gamma} spectrometry. For fuel elements containing uranium 235, the measurements concern the photoelectric peak at 2.18 MeV of {sup 144}Ce which has a half-life of 290 days. The same method could be applied under certain conditions: a) to the measurement of the number of fissions due to {sup 239}Pu, by dosing the {sup 106}Rh deriving from the {sup 106}Ru and having a half-life of 370 days. b) and therefore possibly to the non-destructive determination of the quantity of {sup 239}Pu present in a fuel element. If the operational programme of the reactor is known as a function of time, the possible field of application of the method is extended to times of irradiation of from two to three years. (authors) [French] Nous avons mis au point une methode de mesure non destructive du taux de combustion d'un combustible nucleaire. Son principe repose sur la determination quantitative d'un produit de fission par spectrometrie {gamma}. Pour les elements combustibles utilisant l'uranium 235, les mesures portent sur le pic photoelectrique a 2,18 MeV du {sup 144}Pr fils du {sup 144}Ce de periode 290 jours. La meme methode pourrait etre appliquee sous certaines conditions : a) a la mesure du nombre de fissions dues au {sup 239}Pu en faisant le dosage du {sup 106}Rh fils du {sup 106}Ru de periode 370 jours. b) donc eventuellement a la determination non destructive de la quantite du {sup 239}Pu contenue dans un element combustible. Si le programme de fonctionnement dans le temps du reacteur est connu, le domaine d'application de la methode s'etend a des durees d'irradiation pouvant atteindre deux a trois ans. (auteurs)

  20. SOURCE OF BURNUP VALUES FOR COMMERCIAL SPENT NUCLEAR FUEL ASSEMBLIES

    Energy Technology Data Exchange (ETDEWEB)

    BSC

    2004-12-01

    , initial {sup 235}U enrichment, and time of discharge from the reactor as well as the assigned burnup, but the distribution. of burnup axially along the assembly length is not provided. The axial burnup profile is maintained within acceptable bounds by the operating conditions of the nuclear reactor and is calculated during preparations to reload a reactor, but the actual burnup profile is not measured. The axial burnup profile is important to the determination of the reactivity of a waste package, so a conservative evaluation of the calculated axial profiles for a large database of SNF has been performed. The product of the axial profile evaluation is a profile that is conservative. Thus, there is no need for physical measurement of the axial profile. The assembly identifier is legible on each SNF assembly and the utility records provide the associated characteristics of the assembly. The conservative methodologies used to determine the criticality loading curve for a waste package provide sufficient margin so that criticality safety is assured for preclosure operations even in the event of a misload. Consideration of misload effects for postclosure time periods is provided by the criticality Features, Events, and Processes (FEPs) analysis. The conservative approaches used to develop and apply the criticality loading curve are thus sufficiently robust that the utility assigned burnup is an adequate source of burnup values, and additional means of verification of assigned burnup through physical measurements are not needed.

  1. Conservative approach for PWR MOX Burnup Credit implementation

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    Jutier, Ludyvine; Checiak, Benoit; Raby, Jerome; Aguiar, Luis; Le Bars, Igor [IRSN, Fontenay-aux-Roses (France)

    2008-07-01

    Burnup Credit allows considering the reactivity decrease due to fuel irradiation in criticality studies for the nuclear fuel cycle. Its implementation requires to carefully analyze the validity of the assumption made to: define the axial profile of the burnup, determine the composition of the irradiated fuel and compute the criticality simulation. In the framework of Burnup Credit implementation for PWR mixed oxide fuels (MOX), this paper focus on the determination of a conservative inventory of the irradiated fuel. The studies presented in this paper concern: the influence of irradiation conditions and of the MOX fuel initial composition on the irradiated MOX fuel reactivity. Criticality calculations are also performed for PWR MOX fuel industrial applications in order to get Burnup Credit gain estimations. (authors)

  2. Radiochemical Assays of Irradiated VVER-440 Fuel for Use in Spent Fuel Burnup Credit Activities

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, L J

    2005-04-25

    The objective of this spent fuel burnup credit work was to study and describe a VVER-440 reactor spent fuel assembly (FA) initial state before irradiation, its operational irradiation history and the resulting radionuclide distribution in the fuel assembly after irradiation. This work includes the following stages: (1) to pick out and select a specific spent (irradiated) FA for examination; (2) to describe the FA initial state before irradiation; (3) to describe the irradiation history, including thermal calculations; (4) to examine the burnup distribution of select radionuclides along the FA height and cross-section; (5) to examine the radionuclide distributions; (6) to determine the Kr-85 release into the plenum; (7) to select and prepare FA rod specimens for destructive examinations; (8) to determine the radionuclide compositions, isotope masses and burnup in the rod specimens; and (9) to analyze, document and process the results. The specific workscope included the destructive assay (DA) of spent fuel assembly rod segments with an {approx}38.5 MWd/KgU burnup from a single VVER-440 fuel assembly from the Novovorenezh reactor in Russia. Based on irradiation history criteria, four rods from the fuel assembly were selected and removed from the assembly for examination. Next, 8 sections were cut from the four rods and sent for destructive analysis of radionuclides by radiochemical analyses. The results were documented in a series of seven reports over a period of {approx}1 1/2 years.

  3. Determination of uranium concentration and burn-up of irradiated reactor fuel in contaminated areas in Belarus using uranium isotopic ratios in soil samples

    OpenAIRE

    Mironov, V. P.; Matusevich, J. L.; Kudrjashov, V. P.; Ananich, P. I.; Zhuravkov, V. V.; Boulyga, S. F.; Becker, J. S.

    2005-01-01

    An analytical method is described for the estimation of uranium concentrations, of U-235/U-238 and U-236/U-238 isotope ratios and burn-up of irradiated reactor uranium in contaminated soil samples by inductively coupled plasma mass spectrometry. Experimental results obtained at 12 sampling sites situated on northern and western radioactive fallout tails 4 to 53 km distant from Chernobyl nuclear power plant (NPP) are presented. Concentrations of irradiated uranium in the upper 0-10cm soil laye...

  4. Analysis of high burnup pressurized water reactor fuel using uranium, plutonium, neodymium, and cesium isotope correlations with burnup

    Directory of Open Access Journals (Sweden)

    Jung Suk Kim

    2015-12-01

    Full Text Available The correlation of the isotopic composition of uranium, plutonium, neodymium, and cesium with the burnup for high burnup pressurized water reactor fuels irradiated in nuclear power reactors has been experimentally investigated. The total burnup was determined by Nd-148 and the fractional 235U burnup was determined by U and Pu mass spectrometric methods. The isotopic compositions of U, Pu, Nd, and Cs after their separation from the irradiated fuel samples were measured using thermal ionization mass spectrometry. The contents of these elements in the irradiated fuel were determined through an isotope dilution mass spectrometric method using 233U, 242Pu, 150Nd, and 133Cs as spikes. The activity ratios of Cs isotopes in the fuel samples were determined using gamma-ray spectrometry. The content of each element and its isotopic compositions in the irradiated fuel were expressed by their correlation with the total and fractional burnup, burnup parameters, and the isotopic compositions of different elements. The results obtained from the experimental methods were compared with those calculated using the ORIGEN-S code.

  5. Quantification of the computational accuracy of code systems on the burn-up credit using experimental re-calculations; Quantifizierung der Rechengenauigkeit von Codesystemen zum Abbrandkredit durch Experimentnachrechnungen

    Energy Technology Data Exchange (ETDEWEB)

    Behler, Matthias; Hannstein, Volker; Kilger, Robert; Moser, Franz-Eberhard; Pfeiffer, Arndt; Stuke, Maik

    2014-06-15

    In order to account for the reactivity-reducing effect of burn-up in the criticality safety analysis for systems with irradiated nuclear fuel (''burnup credit''), numerical methods to determine the enrichment and burnup dependent nuclide inventory (''burnup code'') and its resulting multiplication factor k{sub eff} (''criticality code'') are applied. To allow for reliable conclusions, for both calculation systems the systematic deviations of the calculation results from the respective true values, the bias and its uncertainty, are being quantified by calculation and analysis of a sufficient number of suitable experiments. This quantification is specific for the application case under scope and is also called validation. GRS has developed a methodology to validate a calculation system for the application of burnup credit in the criticality safety analysis for irradiated fuel assemblies from pressurized water reactors. This methodology was demonstrated by applying the GRS home-built KENOREST burnup code and the criticality calculation sequence CSAS5 from SCALE code package. It comprises a bounding approach and alternatively a stochastic, which both have been exemplarily demonstrated by use of a generic spent fuel pool rack and a generic dry storage cask, respectively. Based on publicly available post irradiation examination and criticality experiments, currently the isotopes of uranium and plutonium elements can be regarded for.

  6. Modelling of fission gas swelling in the high burnup UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Ho; Lee, Chan Bock; Bang, Je Gun; Jung, Yeon Ho

    1999-06-01

    Discharge burnup of the fuel in LWR has been increased to improve the fuel economy, and currently the high burnup fuel of over 70 MWd/kg U-rod avg. is being developed by the fuel vendors worldwide. At high burnup, thermal / mechanical properties of the fuel is known to change and new phenomenon could arise. This report describes the model development on fission gas swelling in high burnup UO{sub 2} fuel. For the low burnup fuel, swelling only by the solid fission products has been considered in the fuel performance analysis. However, at high burnup fuel, swelling by fission gas bubbles can not be neglected anymore. Therefore, fission gas swelling model which can predictbubble swelling of the high burnup UO{sub 2} fuel during the steady-state and the transient conditions in LWR was developed. Based on the bubble growth model, the empirical fission gas swelling model was developed as function of burnup, time and temperature. The model showed that fuel bubble swelling would be proportional to the burnup by the power of 1.157 and to the time by the power of 0.157. Comparison of the model prediction with the measured fission gas swelling data under the various burnup and temperature conditions showed that the model would predict the measured data reasonably well. (author). 20 refs., 8 tabs., 17 figs.

  7. OECD/NEA burnup credit calculational criticality benchmark Phase I-B results

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, M.D.; Parks, C.V. [Oak Ridge National Lab., TN (United States); Brady, M.C. [Sandia National Labs., Las Vegas, NV (United States)

    1996-06-01

    In most countries, criticality analysis of LWR fuel stored in racks and casks has assumed that the fuel is fresh with the maximum allowable initial enrichment. This assumption has led to the design of widely spaced and/or highly poisoned storage and transport arrays. If credit is assumed for fuel burnup, initial enrichment limitations can be raised in existing systems, and more compact and economical arrays can be designed. Such reliance on the reduced reactivity of spent fuel for criticality control is referred to as burnup credit. The Burnup Credit Working Group, formed under the auspices of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development, has established a set of well-defined calculational benchmarks designed to study significant aspects of burnup credit computational methods. These benchmarks are intended to provide a means for the intercomparison of computer codes, methods, and data applied in spent fuel analysis. The benchmarks have been divided into multiple phases, each phase focusing on a particular feature of burnup credit analysis. This report summarizes the results and findings of the Phase I-B benchmark, which was proposed to provide a comparison of the ability of different code systems and data libraries to perform depletion analysis for the prediction of spent fuel isotopic concentrations. Results included here represent 21 different sets of calculations submitted by 16 different organizations worldwide and are based on a limited set of nuclides determined to have the most important effect on the neutron multiplication factor of light-water-reactor spent fuel. A comparison of all sets of results demonstrates that most methods agree to within 10% in the ability to estimate the spent fuel concentrations of most actinides. All methods agree within 11% about the average for all fission products studied. Most deviations are less than 10%, and many are less than 5%. The exceptions are Sm 149, Sm 151, and Gd 155.

  8. Burn-up calculation of different thorium-based fuel matrixes in a thermal research reactor using MCNPX 2.6 code

    Directory of Open Access Journals (Sweden)

    Gholamzadeh Zohreh

    2014-12-01

    Full Text Available Decrease of the economically accessible uranium resources and the inherent proliferation resistance of thorium fuel motivate its application in nuclear power systems. Estimation of the nuclear reactor’s neutronic parameters during different operational situations is of key importance for the safe operation of nuclear reactors. In the present research, thorium oxide fuel burn-up calculations for a demonstrative model of a heavy water- -cooled reactor have been performed using MCNPX 2.6 code. Neutronic parameters for three different thorium fuel matrices loaded separately in the modelled thermal core have been investigated. 233U, 235U and 239Pu isotopes have been used as fissile element in the thorium oxide fuel, separately. Burn-up of three different fuels has been calculated at 1 MW constant power. 135X and 149Sm concentration variations have been studied in the modelled core during 165 days burn-up. Burn-up of thorium oxide enriched with 233U resulted in the least 149Sm and 135Xe productions and net fissile production of 233U after 165 days. The negative fuel, coolant and void reactivity of the used fuel assures safe operation of the modelled thermal core containing (233U-Th O2 matrix. Furthermore, utilisation of thorium breeder fuel demonstrates several advantages, such as good neutronic economy, 233U production and less production of long-lived α emitter high radiotoxic wastes in biological internal exposure point of view

  9. Evaluation of Fission Product Critical Experiments and Associated Biases for Burnup Credit Validation

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Rearden, Bradley T [ORNL; Reed, Davis Allan [ORNL

    2010-01-01

    One of the challenges associated with implementation of burnup credit is the validation of criticality calculations used in the safety evaluation; in particular the availability and use of applicable critical experiment data. The purpose of the validation is to quantify the relationship between reality and calculated results. Validation and determination of bias and bias uncertainty require the identification of sets of critical experiments that are similar to the criticality safety models. A principal challenge for crediting fission products (FP) in a burnup credit safety evaluation is the limited availability of relevant FP critical experiments for bias and bias uncertainty determination. This paper provides an evaluation of the available critical experiments that include FPs, along with bounding, burnup-dependent estimates of FP biases generated by combining energy dependent sensitivity data for a typical burnup credit application with the nuclear data uncertainty information distributed with SCALE 6. A method for determining separate bias and bias uncertainty values for individual FPs and illustrative results is presented. Finally, a FP bias calculation method based on data adjustment techniques and reactivity sensitivity coefficients calculated with the SCALE sensitivity/uncertainty tools and some typical results is presented. Using the methods described in this paper, the cross-section bias for a representative high-capacity spent fuel cask associated with the ENDF/B-VII nuclear data for 16 most important stable or near stable FPs is predicted to be no greater than 2% of the total worth of the 16 FPs, or less than 0.13 % k/k.

  10. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Science.gov (United States)

    Favalli, A.; Vo, D.; Grogan, B.; Jansson, P.; Liljenfeldt, H.; Mozin, V.; Schwalbach, P.; Sjöland, A.; Tobin, S. J.; Trellue, H.; Vaccaro, S.

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity's behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  11. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Favalli, A., E-mail: afavalli@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM (United States); Vo, D. [Los Alamos National Laboratory, Los Alamos, NM (United States); Grogan, B. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Jansson, P. [Uppsala University, Uppsala (Sweden); Liljenfeldt, H. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mozin, V. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Schwalbach, P. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg); Sjöland, A. [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Tobin, S.J.; Trellue, H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Vaccaro, S. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg)

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)–Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute {sup 137}Cs count rate and the {sup 154}Eu/{sup 137}Cs, {sup 134}Cs/{sup 137}Cs, {sup 106}Ru/{sup 137}Cs, and {sup 144}Ce/{sup 137}Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity’s behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  12. High burnup fuel onset conditions in dry storage. Prediction of EOL rod internal pressure

    Energy Technology Data Exchange (ETDEWEB)

    Feria, F.; Herranz, L.E.

    2015-07-01

    During dry storage, cladding resistance to failure can be affected by several degrading mechanisms like creep or hydrides radial reorientation. The driving force of these effects is the stress at which the cladding is submitted. The maximum stress in the cladding is determined by the end-of-reactor-life (EOL) rod internal pressure, PEOL, at the maximum temperature attained during dry storage. Thus, PEOL sets the initial conditions of storage for potential time-dependent changes in the cladding. Based on FRAPCON-3.5 calculations, the aim of this work is to analyse the PEOL of a PWR fuel rod irradiated to burnups greater than 60 GWd/tU, where limited information is available. In order to be conservative, demanding irradiation histories have been used with a peak linear power of 44 kW/m. FRAPCON-3.5 results show an increasing exponential trend of PEOL with burnup, from which a simple correlation has been derived. The comparison with experimental data found in the literature confirms the enveloping nature of the predicted curve. Based on that, a conservative prediction of cladding stress in dry storage has been obtained. The comparison with a critical stress threshold related to hydrides embrittlement seems to point out that this issue should not be a concern at burnups below 65 GWd/tU. (Author)

  13. Manufacturing Data Uncertainties Propagation Method in Burn-Up Problems

    Directory of Open Access Journals (Sweden)

    Thomas Frosio

    2017-01-01

    Full Text Available A nuclear data-based uncertainty propagation methodology is extended to enable propagation of manufacturing/technological data (TD uncertainties in a burn-up calculation problem, taking into account correlation terms between Boltzmann and Bateman terms. The methodology is applied to reactivity and power distributions in a Material Testing Reactor benchmark. Due to the inherent statistical behavior of manufacturing tolerances, Monte Carlo sampling method is used for determining output perturbations on integral quantities. A global sensitivity analysis (GSA is performed for each manufacturing parameter and allows identifying and ranking the influential parameters whose tolerances need to be better controlled. We show that the overall impact of some TD uncertainties, such as uranium enrichment, or fuel plate thickness, on the reactivity is negligible because the different core areas induce compensating effects on the global quantity. However, local quantities, such as power distributions, are strongly impacted by TD uncertainty propagations. For isotopic concentrations, no clear trends appear on the results.

  14. The burnup dependence of light water reactor spent fuel oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, B.D.

    1998-07-01

    Over the temperature range of interest for dry storage or for placement of spent fuel in a permanent repository under the conditions now being considered, UO{sub 2} is thermodynamically unstable with respect to oxidation to higher oxides. The multiple valence states of uranium allow for the accommodation of interstitial oxygen atoms in the fuel matrix. A variety of stoichiometric and nonstoichiometric phases is therefore possible as the fuel oxidizers from UO{sub 2} to higher oxides. The oxidation of UO{sub 2} has been studied extensively for over 40 years. It has been shown that spent fuel and unirradiated UO{sub 2} oxidize via different mechanisms and at different rates. The oxidation of LWR spent fuel from UO{sub 2} to UO{sub 2.4} was studied previously and is reasonably well understood. The study presented here was initiated to determine the mechanism and rate of oxidation from UO{sub 2.4} to higher oxides. During the early stages of this work, a large variability in the oxidation behavior of samples oxidized under nearly identical conditions was found. Based on previous work on the effect of dopants on UO{sub 2} oxidation and this initial variability, it was hypothesized that the substitution of fission product and actinide impurities for uranium atoms in the spent fuel matrix was the cause of the variable oxidation behavior. Since the impurity concentration is roughly proportional to the burnup of a specimen, the oxidation behavior of spent fuel was expected to be a function of both temperature and burnup. This report (1) summarizes the previous oxidation work for both unirradiated UO{sub 2} and spent fuel (Section 2.2) and presents the theoretical basis for the burnup (i.e., impurity concentration) dependence of the rate of oxidation (Sections 2.3, 2.4, and 2.5), (2) describes the experimental approach (Section 3) and results (Section 4) for the current oxidation tests on spent fuel, and (3) establishes a simple model to determine the activation energies

  15. Review of Technical Studies in the United States in Support of Burnup Credit Regulatory Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, John C [ORNL; Parks, Cecil V [ORNL; Mueller, Don [ORNL; Gauld, Ian C [ORNL

    2010-01-01

    Taking credit for the reduction in reactivity associated with fuel depletion can enable more cost-effective, higher-density storage, transport, disposal, and reprocessing of spent nuclear fuel (SNF) while maintaining sufficient subcritical margin to establish an adequate safety basis. Consequently, there continues to be considerable interest in the United States (U.S.), as well as internationally, in the increased use of burnup credit in SNF operations, particularly related to storage, transport, and disposal of commercial SNF. This interest has motivated numerous technical studies related to the application of burnup credit, both domestically and internationally, as well as the design of SNF storage, transport and disposal systems that rely on burnup credit for maintaining subcriticality. Responding to industry requests and needs, the U.S. Nuclear Regulatory Commission (NRC) initiated a burnup credit research program in 1999, with support from the Oak Ridge National Laboratory (ORNL), to develop regulatory guidance and the supporting technical bases for allowing and expanding the use of burnup credit in pressurized-water reactor SNF storage and transport applications. Although this NRC research program has not been continuous since its inception, considerable progress has been achieved in many key areas in terms of increased understanding of relevant phenomena and issues, availability of relevant information and data, and subsequently updated regulatory guidance for expanded use of burnup credit. This paper reviews technical studies performed by ORNL for the U.S. NRC burnup credit research program. Examples of topics include reactivity effects associated with reactor operating characteristics, fuel assembly characteristics, burnable absorbers, control rods, spatial burnup distributions, cooling time, and assembly misloading; methods and data for validation of isotopic composition predictions; methods and data for validation of criticality calculations; and

  16. Investigation of very high burnup UO{sub 2} fuels in Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Cappia, Fabiola

    2017-03-27

    fuel mechanical properties and their relationship with the local microstructure at high burnup has been recognised, being one of the factors influencing Pellet-Cladding Mechanical Interaction (PCMI). The knowledge of the fuel mechanical properties has also fundamental importance to assess the mechanical integrity of the spent fuel during the back end of the fuel cycle. In this context, the scope of this work was twofold. The first task was the experimental study of the fuel microhardness and Young's modulus in high burnup UO{sub 2} fuels and their relationship with the local porosity, which has a major impact on their variation. Moreover, assessment of the accumulation of the decay damage during storage and its influence on the fuel microhardness has been carried out, in the framework of safety studies on the back end of the fuel cycle at high burnup. The second task consisted in the evaluation of the porosity and pore size distribution evolution in high burnup fuel, with particular focus on the HBS porosity. The experimental relationship between the high burnup fuel Young's modulus and local porosity obtained through combination of acoustic microscopy and microindentation measurements has been compared to the material property correlations commonly used in fuel performance codes, which are based on data from characterization of unirradiated UO{sub 2}. The investigation has revealed that the relationship is similar for non-irradiated and irradiated material, but in the latter case an additional factor that takes into account the Young's modulus decrease due to burnup accumulation has to be included in the correlation to match the experimental values. First analysis of the fuel microhardness as a function of the accumulated decay damage has shown that fuel microhardness does not significantly increase when the dose due to the additional decay damage accumulated during storage reaches ∼ 0.1 dpa, in agreement with what observed in unirradiated {sup 238}Pu

  17. An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Isotopic Composition Predictions

    Energy Technology Data Exchange (ETDEWEB)

    Radulescu, Georgeta [ORNL; Gauld, Ian C [ORNL; Ilas, Germina [ORNL; Wagner, John C [ORNL

    2011-01-01

    The expanded use of burnup credit in the United States (U.S.) for storage and transport casks, particularly in the acceptance of credit for fission products, has been constrained by the availability of experimental fission product data to support code validation. The U.S. Nuclear Regulatory Commission (NRC) staff has noted that the rationale for restricting the Interim Staff Guidance on burnup credit for storage and transportation casks (ISG-8) to actinide-only is based largely on the lack of clear, definitive experiments that can be used to estimate the bias and uncertainty for computational analyses associated with using burnup credit. To address the issues of burnup credit criticality validation, the NRC initiated a project with the Oak Ridge National Laboratory to (1) develop and establish a technically sound validation approach for commercial spent nuclear fuel (SNF) criticality safety evaluations based on best-available data and methods and (2) apply the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The purpose of this paper is to describe the isotopic composition (depletion) validation approach and resulting observations and recommendations. Validation of the criticality calculations is addressed in a companion paper at this conference. For isotopic composition validation, the approach is to determine burnup-dependent bias and uncertainty in the effective neutron multiplication factor (keff) due to bias and uncertainty in isotopic predictions, via comparisons of isotopic composition predictions (calculated) and measured isotopic compositions from destructive radiochemical assay utilizing as much assay data as is available, and a best-estimate Monte Carlo based method. This paper (1) provides a detailed description of the burnup credit isotopic validation approach and its technical bases, (2) describes the application of the approach for

  18. Technical Development on Burn-up Credit for Spent LWR Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gauld, I.C.

    2001-12-26

    Technical development on burn-up credit for spent LWR fuels had been performed at JAERI since 1990 under the contract with Science and Technology Agency of Japan entitled ''Technical Development on Criticality Safety Management for Spent LWR Fuels.'' Main purposes of this work are to obtain the experimental data on criticality properties and isotopic compositions of spent LWR fuels and to verify burnup and criticality calculation codes. In this work three major experiments of exponential experiments for spent fuel assemblies to obtain criticality data, non-destructive gamma-ray measurement of spent fuel rods for evaluating axial burn-up profiles, and destructive analyses of spent fuel samples for determining precise burn-up and isotopic compositions were carried out. The measured data obtained were used for validating calculation codes as well as an examination of criticality safety analyses. Details of the work are described in this report.

  19. Apparatus for in situ determination of burnup, cooling time and fissile content of an irradiated nuclear fuel assembly in a fuel storage pond

    Science.gov (United States)

    Phillips, John R.; Halbig, James K.; Menlove, Howard O.; Klosterbuer, Shirley F.

    1985-01-01

    A detector head for in situ inspection of irradiated nuclear fuel assemblies submerged in a water-filled nuclear fuel storage pond. The detector head includes two parallel arms which extend from a housing and which are spaced apart so as to be positionable on opposite sides of a submerged fuel assembly. Each arm includes an ionization chamber and two fission chambers. One fission chamber in each arm is enclosed in a cadmium shield and the other fission chamber is unshielded. The ratio of the outputs of the shielded and unshielded fission chambers is used to determine the boron content of the pond water. Correcting for the boron content, the neutron flux and gamma ray intensity are then used to verify the declared exposure, cooling time and fissile material content of the irradiated fuel assembly.

  20. New burnup calculation of TRIGA IPR-R1 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Meireles, Sincler P. de; Campolina, Daniel de A.M.; Santos, Andre A. Campagnole dos; Menezes, Maria A.B.C.; Mesquita, Amir Z., E-mail: sinclercdtn@hotmail.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    The IPR-R1 TRIGA Mark I research reactor, located at the Nuclear Technology Development Center - CDTN, Belo Horizonte, Brazil, operates since 1960.The reactor is operating for more than fifty years and has a long history of operation. Determining the current composition of the fuel is very important to calculate various parameters. The reactor burnup calculation has been performed before, however, new techniques, methods, software and increase of the processing capacity of the new computers motivates new investigations to be performed. This work presents the evolution of effective multiplication constant and the results of burnup. This new model has a more detailed geometry with the introduction of the new devices, like the control rods and the samarium discs. This increase of materials in the simulation in burnup calculation was very important for results. For these series of simulations a more recently cross section library, ENDF/B-VII, was used. To perform the calculations two Monte Carlo particle transport code were used: Serpent and MCNPX. The results obtained from two codes are presented and compared with previous studies in the literature. (author)

  1. Corrosion studies with high burnup light water reactor fuel. Release of nuclides into simulated groundwater during accumulated contact time of up to two years

    Energy Technology Data Exchange (ETDEWEB)

    Zwicky, Hans-Urs (Zwicky Consulting GmbH, Remigen (Switzerland)); Low, Jeanett; Ekeroth, Ella (Studsvik Nuclear AB, Nykoeping (Sweden))

    2011-03-15

    In the framework of comprehensive research work supporting the development of a Swedish concept for the disposal of highly radioactive waste and spent fuel, Studsvik has performed a significant number of spent fuel corrosion studies under a variety of different conditions. These experiments, performed between 1990 and 2002, covered a burnup range from 27 to 49 MWd/kgU, which was typical for fuel to be disposed at that time. As part of this work, the so called Series 11 tests were performed under oxidising conditions in synthetic groundwater with fuel samples from a rod irradiated in the Ringhals 1 Boiling Water Reactor (BWR). In the meantime, Swedish utilities tend to increase the discharge burnup of fuel operated in their reactors. This means that knowledge of spent fuel corrosion performance has to be extended to higher burnup as well. Therefore, a series of experiments has been started at Studsvik, aiming at extending the data base acquired in the Series 11 corrosion tests to higher burnup fuel. Fuel burnup leads to complex and significant changes in the composition and properties of the fuel. The transformed microstructure, which is referred to as the high burnup structure or rim structure in the outer region of the fuel, consists of small grains of submicron size and a high concentration of pores of typical diameter 1 to 2 mum. This structure forms in UO{sub 2} fuel at a local burnup above 50 MWd/kgU, as long as the temperature is below 1,000-1,100 deg C. The high burnup at the pellet periphery is the consequence of plutonium build-up by neutron capture in 238U followed by fission of the formed plutonium. The amount of fission products in the fuel increases more or less linearly with burnup, in contrast to alpha emitting actinides that increase above average. As burnup across a spent fuel pellet is not uniform, but increases towards the periphery, the radiation field is also larger at the pellet surface. At the same time, it is easier for water to access the

  2. Actinide-only and full burn-up credit in criticality assessment of RBMK-1500 spent nuclear fuel storage cask using axial burn-up profile

    Energy Technology Data Exchange (ETDEWEB)

    Barkauskas, V., E-mail: vytenis.barkauskas@ftmc.lt; Plukiene, R., E-mail: rita.plukiene@ftmc.lt; Plukis, A., E-mail: arturas.plukis@ftmc.lt

    2016-10-15

    Highlights: • RBMK-1500 fuel burn-up impact on k{sub eff} in the SNF cask was calculated using SCALE 6.1. • Positive end effect was noticed at certain burn-up for the RBMK-1500 spent nuclear fuel. • The non-uniform uranium depletion is responsible for the end effect in RBMK-1500 SNF. • k{sub eff} in the SNF cask does not exceed a value of 0.95 which is set in the safety requirements. - Abstract: Safe long-term storage of spent nuclear fuel (SNF) is one of the main issues in the field of nuclear safety. Burn-up credit application in criticality analysis of SNF reduces conservatism of usually used fresh fuel assumption and implies a positive economic impact for the SNF storage. Criticality calculations of spent nuclear fuel in the CONSTOR® RBMK-1500/M2 cask were performed using pre-generated ORIGEN-ARP spent nuclear fuel composition libraries, and the results of the RBMK-1500 burn-up credit impact on the effective neutron multiplication factor (k{sub eff}) have been obtained and are presented in the paper. SCALE 6.1 code package with the STARBUCKS burn-up credit evaluation tool was used for modeling. Pre-generated ARP (Automatic Rapid Processing) crosssection libraries based on ENDF/B-VII cross section library were used for fast burn-up inventory modeling. Different conditions in the SNF cask were modeled: 2.0% and 2.8% initial enrichment fuel of various burn-up and water density inside cavities of the SNF cask. The fuel composition for the criticality analysis was chosen taking into account main actinides and most important fission products used in burn-up calculations. A significant positive end effect is noticed from 15 GWd/tU burn-up for 2.8% enrichment fuel and from 9 GWd/tU for 2.0% enrichment fuel applying the actinide-only approach. The obtained results may be applied in further evaluations of the RBMK type reactor SNF storage as well as help to optimize the SNF storage volume inside the CONSTOR® RBMK-1500/M2 cask without compromising criticality

  3. Technical Data to Justify Full Burnup Credit in Criticality Safety Licensing Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Enercon Services, Inc.

    2011-03-14

    ENERCON's understanding of the difficult issues related to obtaining and analyzing additional cross section test data to support Full Burnup Credit. A PIRT (Phenomena Identification and Ranking Table) analysis was performed by ENERCON to evaluate the costs and benefits of acquiring different types of nuclear data in support of Full Burnup Credit. A PIRT exercise is a formal expert elicitation process with the final output being the ranking tables. The PIRT analysis (Table 7-4: Results of PIRT Evaluation) showed that the acquisition of additional Actinide-Only experimental data, although beneficial, was associated with high cost and is not necessarily needed. The conclusion was that the existing Radiochemical Assay (RCA) data plus the French Haut Taux de Combustion (HTC)2 and handbook Laboratory Critical Experiment (LCE) data provide adequate benchmark validation for Actinide-Only Burnup Credit. The PIRT analysis indicated that the costs and schedule to obtain sufficient additional experimental data to support the addition of 16 fission products to Actinide-Only Burnup Credit to produce Full Burnup Credit are quite substantial. ENERCON estimates the cost to be $50M to $100M with a schedule of five or more years. The PIRT analysis highlights another option for fission product burnup credit, which is the application of computer-based uncertainty analyses (S/U - Sensitivity/Uncertainty methodologies), confirmed by the limited experimental data that is already available. S/U analyses essentially transform cross section uncertainty information contained in the cross section libraries into a reactivity bias and uncertainty. Recent work by ORNL and EPRI has shown that a methodology to support Full Burnup Credit is possible using a combination of traditional RCA and LCE validation plus S/U validation for fission product isotopics and cross sections. Further, the most recent cross section data (ENDF/B-VII) can be incorporated into the burnup credit codes at a reasonable cost

  4. Models for fuel rod behaviour at high burnup

    Energy Technology Data Exchange (ETDEWEB)

    Jernkvist, Lars O.; Massih, Ali R. [Quantum Technologies AB, Uppsala Science Park, Uppsala (Sweden)

    2004-12-01

    This report deals with release of fission product gases and irradiation-induced restructuring in uranium dioxide nuclear fuel. Waterside corrosion of zirconium alloy clad tubes to light water reactor fuel rods is also discussed. Computational models, suitable for implementation in the FRAPCON-3.2 computer code, are proposed for these potentially life-limiting phenomena. Hence, an integrated model for the calculation or thermal fission gas release by intragranular diffusion, gas trapping in grain boundaries, irradiation-induced re-solution, grain boundary saturation, and grain boundary sweeping in UO{sub 2} fuel, under time varying temperature loads, is formulated. After a brief review of the status of thermal fission gas release modelling, we delineate the governing equations for the aforementioned processes. Grain growth kinetic modelling is briefly reviewed and pertinent data on grain growth of high burnup fuel obtained during power ramps in the Third Risoe Fission Gas Release Project are evaluated. Sample computations are performed, which clearly show the connection between fission gas release and gram growth as a function of time at different isotherms. Models are also proposed for the restructuring of uranium dioxide fuel at high burnup, the so-called rim formation, and its effect on fuel porosity build-up, fuel thermal conductivity and fission gas release. These models are assessed by use of recent experimental data from the High Burnup Rim Project, as well as from post irradiation examinations of high-burnup fuel, irradiated in power reactors. Moreover, models for clad oxide growth and hydrogen pickup in PWRs, applicable to Zircaloy-4, ZIRLO or M5 cladding, are formulated, based on recent in-reactor corrosion data for high-burnup fuel rods. Our evaluation of these data indicates that the oxidation rate of ZIRLO-type materials is about 20% lower than for standard Zircaloy-4 cladding under typical PWR conditions. Likewise, the oxidation rate of M5 seems to be

  5. Tritium release from EXOTIC-7 orthosilicate pebbles. Effect of burnup and contact with beryllium during irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Werle, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reaktortechnik

    1998-03-01

    EXOTIC-7 was the first in-pile test with {sup 6}Li-enriched (50%) lithium orthosilicate (Li{sub 4}SiO{sub 4}) pebbles and with DEMO representative Li-burnup. Post irradiation examinations of the Li{sub 4}SiO{sub 4} have been performed at the Forschungszentrum Karlsruhe (FZK), mainly to investigate the tritium release kinetics as well as the effect of Li-burnup and/or contact with beryllium during irradiation. The release rate of Li{sub 4}SiO{sub 4} from pure Li{sub 4}SiO{sub 4} bed of capsule 28.1-1 is characterized by a broad main peak at about 400degC and by a smaller peak at about 800degC, and that from the mixed beds of capsule 28.2 and 26.2-1 shows again these two peaks, but most of the tritium is now released from the 800degC peak. This shift of release from low to high temperature may be due to the higher Li-burnup and/or due to contact with Be during irradiation. Due to the very difficult interpretation of the in-situ tritium release data, residence times have been estimated on the basis of the out-of-pile tests. The residence time for Li{sub 4}SiO{sub 4} from caps. 28.1-1 irradiated at 10% Li-burnup agrees quite well with that of the same material irradiated at Li-burnup lower than 3% in the EXOTIC-6 experiment. In spite of the observed shift in the release peaks from low to high temperature, also the residence time for Li{sub 4}SiO{sub 4} from caps. 26.2-1 irradiated at 13% Li-burnup agrees quite well with the data from EXOTIC-6 experiment. On the other hand, the residence time for Li{sub 4}SiO{sub 4} from caps. 28.2 (Li-burnup 18%) is about a factor 1.7-3.8 higher than that for caps. 26.2-1. Based on these data on can conclude that up to 13% Li-burnup neither the contact with beryllium nor the Li-burnup have a detrimental effect on the tritium release of Li{sub 4}SiO{sub 4} pebbles, but at 18% Li-burnup the residence time is increased by about a factor three. (J.P.N.)

  6. A simple gamma spectrometry method for evaluating the burnup of MTR-type HEU fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Makmal, T. [The Unit of Nuclear Engineering, Ben-Gurion University of The Negev, Beer-Sheva 84105 (Israel); Nuclear Physics and Engineering Division, Soreq Nuclear Research Center, Yavne 81800 (Israel); Aviv, O. [Radiation Safety Division, Soreq Nuclear Research Center, Yavne 81800 (Israel); Gilad, E., E-mail: gilade@bgu.ac.il [The Unit of Nuclear Engineering, Ben-Gurion University of The Negev, Beer-Sheva 84105 (Israel)

    2016-10-21

    A simple method for the evaluation of the burnup of a materials testing reactor (MTR) fuel element by gamma spectrometry is presented. The method was applied to a highly enriched uranium MTR nuclear fuel element that was irradiated in a 5 MW pool-type research reactor for a total period of 34 years. The experimental approach is based on in-situ measurements of the MTR fuel element in the reactor pool by a portable high-purity germanium detector located in a gamma cell. To corroborate the method, analytical calculations (based on the irradiation history of the fuel element) and computer simulations using a dedicated fuel cycle burnup code ORIGEN2 were performed. The burnup of the MTR fuel element was found to be 52.4±8.8%, which is in good agreement with the analytical calculations and the computer simulations. The method presented here is suitable for research reactors with either a regular or an irregular irradiation regime and for reactors with limited infrastructure and/or resources. In addition, its simplicity and the enhanced safety it confers may render this method suitable for IAEA inspectors in fuel element burnup assessments during on-site inspections. - Highlights: • Simple, inexpensive, safe and flexible experimental setup that can be quickly deployed. • Experimental results are thoroughly corroborated against ORIGEN2 burnup code. • Experimental uncertainty of 9% and 5% deviation between measurements and simulations. • Very high burnup MTR fuel element is examined, with 60% depletion of {sup 235}U. • Impact of highly irregular irradiation regime on burnup evaluation is studied.

  7. A criticality analysis of the GBC-32 dry storage cask with Hanbit nuclear power plant unit 3 fuel assemblies from the viewpoint of burnup credit

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyung Ju; Kim, Do Yeon; Park, Kwang Heon; Hong, Ser Gi [Dept. of Nuclear Engineering, Kyung Hee University, Seoul (Korea, Republic of)

    2016-06-15

    Nuclear criticality safety analyses (NCSAs) considering burnup credit were performed for the GBC-32 cask. The used nuclear fuel assemblies (UNFAs) discharged from Hanbit Nuclear Power Plant Unit 3 Cycle 6 were loaded into the cask. Their axial burnup distributions and average discharge burnups were evaluated using the DeCART and Multi-purpose Analyzer for Static and Transient Effects of Reactors (MASTER) codes, and NCSAs were performed using SCALE 6.1/STandardized Analysis of Reactivity for Burnup Credit using SCALE (STARBUCS) and Monte Carlo N-Particle transport code, version 6 (MCNP 6). The axial burnup distributions were determined for 20 UNFAs with various initial enrichments and burnups, which were applied to the criticality analysis for the cask system. The UNFAs for 20- and 30-year cooling times were assumed to be stored in the cask. The criticality analyses indicated that keff values for UNFAs with nonuniform axial burnup distributions were larger than those with a uniform distribution, that is, the end effects were positive but much smaller than those with the reference distribution. The axial burnup distributions for 20 UNFAs had shapes that were more symmetrical with a less steep gradient in the upper region than the reference ones of the United States Department of Energy. These differences in the axial burnup distributions resulted in a significant reduction in end effects compared with the reference.

  8. Technical Basis for Peak Reactivity Burnup Credit for BWR Spent Nuclear Fuel in Storage and Transportation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, William BJ J [ORNL; Ade, Brian J [ORNL; Bowman, Stephen M [ORNL; Gauld, Ian C [ORNL; Ilas, Germina [ORNL; Mertyurek, Ugur [ORNL; Radulescu, Georgeta [ORNL

    2015-01-01

    Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission have initiated a multiyear project to investigate application of burnup credit for boiling-water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase (1) investigates applicability of peak reactivity methods currently used in spent fuel pools (SFPs) to storage and transportation systems and (2) evaluates validation of both reactivity (keff) calculations and burnup credit nuclide concentrations within these methods. The second phase will focus on extending burnup credit beyond peak reactivity. This paper documents the first phase, including an analysis of lattice design parameters and depletion effects, as well as both validation components. Initial efforts related to extended burnup credit are discussed in a companion paper. Peak reactivity analyses have been used in criticality analyses for licensing of BWR fuel in SFPs over the last 20 years. These analyses typically combine credit for the gadolinium burnable absorber present in the fuel with a modest amount of burnup credit. Gadolinium burnable absorbers are used in BWR assemblies to control core reactivity. The burnable absorber significantly reduces assembly reactivity at beginning of life, potentially leading to significant increases in assembly reactivity for burnups less than 15–20 GWd/MTU. The reactivity of each fuel lattice is dependent on gadolinium loading. The number of gadolinium-bearing fuel pins lowers initial lattice reactivity, but it has a small impact on the burnup and reactivity of the peak. The gadolinium concentration in each pin has a small impact on initial lattice reactivity but a significant effect on the reactivity of the peak and the burnup at which the peak occurs. The importance of the lattice parameters and depletion conditions are primarily determined by their impact on the gadolinium depletion. Criticality code validation for BWR burnup

  9. Burn-up dependent steady-state thermal hydraulic analysis of Pakistan research reactor-1

    Directory of Open Access Journals (Sweden)

    Muhammad Atta

    2011-01-01

    Full Text Available The burn-up dependent steady-state thermal hydraulic analysis of Pakistan research reactor-1, reference operating core, has been carried out utilizing standard computer codes WIMS/D4, CITATION, and RELAP5/MOD3.4. Reactor codes WIMS/D4 and CITATION have been used for the calculations of neutronic parameters including peaking factors and power profiles at different burn-up considering a xenon free core and also the equilibrium xenon values. RELAP5/MOD3.4 code was utilized for the determination of peak fuel centerline, clad and coolant temperatures to ensure the safety of the reactor throughout the cycle. The calculations reveal that the reactor is safe and no nucleate boiling will commence at any part of the core throughout the cycle and that the safety margin increases with burnup as peaking factors decrease.

  10. Spent fuel pool storage calculations using the ISOCRIT burnup credit tool

    Energy Technology Data Exchange (ETDEWEB)

    Kucukboyaci, Vefa [Westinghouse Electric Company, Cranberry Township, PA; Marshall, William BJ J [ORNL

    2012-01-01

    In order to conservatively apply burnup credit in spent fuel pool criticality safety analyses, Westinghouse has developed a software tool, ISOCRIT, for generating depletion isotopics. This tool is used to create isotopics data based on specific reactor input parameters, such as design basis assembly type; bounding power/burnup profiles; reactor specific moderator temperature profiles; pellet percent theoretical density; burnable absorbers, axial blanket regions, and bounding ppm boron concentration. ISOCRIT generates burnup dependent isotopics using PARAGON; Westinghouse's state-of-the-art and licensed lattice physics code. Generation of isotopics and passing the data to the subsequent 3D KENO calculations are performed in an automated fashion, thus reducing the chance for human error. Furthermore, ISOCRIT provides the means for responding to any customer request regarding re-analysis due to changed parameters (e.g., power uprate, exit temperature changes, etc.) with a quick turnaround.

  11. Effect of Control Blade History, and Axial Coolant Density and Burnup Profiles on BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, William BJ J [ORNL

    2016-01-01

    A technical basis for peak reactivity boiling water reactor (BWR) burnup credit (BUC) methods was recently generated, and the technical basis for extended BWR BUC is now being developed. In this paper, a number of effects related to extended BWR BUC are analyzed, including three major operational effects in BWRs: the coolant density axial distribution, the use of control blades during operation, and the axial burnup profile. Specifically, uniform axial moderator density profiles are analyzed and compared to previous results and an additional temporal fidelity study combing moderator density profiles for three different fuel assemblies is presented. Realistic control blade histories and cask criticality results are compared to previously generated constructed control blade histories. Finally, a preliminary study of the axial burnup profile is provided.

  12. Study on core physics characteristics of high burn-up full MOX PWR core. 2

    Energy Technology Data Exchange (ETDEWEB)

    Kugo, Teruhiko; Okubo, Tsutomu; Shimada, Syoichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-09-01

    As one of options for future light water reactors, we have been studying a new concept of a high burn-up full MOX PWR core with a discharge burn-up of 100 GWd/t and a 3-year operation cycle being based on the existing light water reactor technology. We have already confirmed the feasibility of the core, in which a moderator to fuel volume ratio(Vm/Vf) is increased to 2.6 with the same fuel pin diameter of 9.5 mm as in the current PWR but with the enlarged fuel pin pitch of 13.8 mm. In this report, to improve the neutronics and thermal hydraulic performance of the high burn-up core, we subsequently propose a 600 MWe core ensuring discharge burn-up of 100 GWd/t by increasing Vm/Vf to 3.0 with the same fuel pin pitch of 12.6 mm as in the current PWR and the smaller fuel rod diameter of 8.3 mm instead of 9.5 mm. We have investigated its core characteristics in neutronics and confirmed its feasibility. The core neutronics performance is compared between Vm/Vf = 2.6 and 3.0. From the comparison, it is found that the proposed core with Vm/Vf 3.0 has more promising characteristics than with Vm/Vf = 2.6 such as saving of a fissile plutonium content of 0.3wt%, improvement in a departure from nucleate boiling ratio (DNBR) and so on, except for a shortened cycle length by 9%. In addition, we have investigated a low-leakage refueling scheme for both types of high burn-up cores. Without modification to fuel material such as addition of burnable poison and/or transuranium isotopes, it can not be expected to improve the burn-up efficiency by the low-leakage refueling scheme. (author)

  13. Application of Genetic Algorithm methodologies in fuel bundle burnup optimization of Pressurized Heavy Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jayalal, M.L., E-mail: jayalal@igcar.gov.in [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Ramachandran, Suja [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Rathakrishnan, S. [Reactor Physics Section, Madras Atomic Power Station (MAPS), Kalpakkam, Tamil Nadu (India); Satya Murty, S.A.V. [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Sai Baba, M. [Resources Management Group (RMG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India)

    2015-01-15

    Highlights: • We study and compare Genetic Algorithms (GA) in the fuel bundle burnup optimization of an Indian Pressurized Heavy Water Reactor (PHWR) of 220 MWe. • Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are considered. • For the selected problem, Multi Objective GA performs better than Penalty Functions based GA. • In the present study, Multi Objective GA outperforms Penalty Functions based GA in convergence speed and better diversity in solutions. - Abstract: The work carried out as a part of application and comparison of GA techniques in nuclear reactor environment is presented in the study. The nuclear fuel management optimization problem selected for the study aims at arriving appropriate reference discharge burnup values for the two burnup zones of 220 MWe Pressurized Heavy Water Reactor (PHWR) core. Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are applied in this study. The study reveals, for the selected problem of PHWR fuel bundle burnup optimization, Multi Objective GA is more suitable than Penalty Functions based GA in the two aspects considered: by way of producing diverse feasible solutions and the convergence speed being better, i.e. it is capable of generating more number of feasible solutions, from earlier generations. It is observed that for the selected problem, the Multi Objective GA is 25.0% faster than Penalty Functions based GA with respect to CPU time, for generating 80% of the population with feasible solutions. When average computational time of fixed generations are considered, Penalty Functions based GA is 44.5% faster than Multi Objective GA. In the overall performance, the convergence speed of Multi Objective GA surpasses the computational time advantage of Penalty Functions based GA. The ability of Multi Objective GA in producing more diverse feasible solutions is a desired feature of the problem selected, that helps the

  14. High Burnup Fuel Performance and Safety Research

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Je Keun; Lee, Chan Bok; Kim, Dae Ho (and others)

    2007-03-15

    The worldwide trend of nuclear fuel development is to develop a high burnup and high performance nuclear fuel with high economies and safety. Because the fuel performance evaluation code, INFRA, has a patent, and the superiority for prediction of fuel performance was proven through the IAEA CRP FUMEX-II program, the INFRA code can be utilized with commercial purpose in the industry. The INFRA code was provided and utilized usefully in the universities and relevant institutes domesticallly and it has been used as a reference code in the industry for the development of the intrinsic fuel rod design code.

  15. Mechanical Fatigue Testing of High Burnup Fuel for Transportation Applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-05-01

    This report describes testing designed to determine the ability of high burnup (HBU) (>45 GWd/MTU) spent fuel to maintain its integrity under normal conditions of transportation. An innovative system, Cyclic Integrated Reversible-bending Fatigue Tester (CIRFT), has been developed at Oak Ridge National Laboratory (ORNL) to test and evaluate the mechanical behavior of spent nuclear fuel (SNF) under conditions relevant to storage and transportation. The CIRFT system is composed of a U-frame equipped with load cells for imposing the pure bending loads on the SNF rod test specimen and measuring the in-situ curvature of the fuel rod during bending using a set up with three linear variable differential transformers (LVDTs).

  16. Modeling of Pore Coarsening in the Rim Region of High Burn-up UO2 Fuel

    Directory of Open Access Journals (Sweden)

    Hongxing Xiao

    2016-08-01

    Full Text Available An understanding of the coarsening process of the large fission gas pores in the high burn-up structure (HBS of irradiated UO2 fuel is very necessary for analyzing the safety and reliability of fuel rods in a reactor. A numerical model for the description of pore coarsening in the HBS based on the Ostwald ripening mechanism, which has successfully explained the coarsening process of precipitates in solids is developed. In this model, the fission gas atoms are treated as the special precipitates in the irradiated UO2 fuel matrix. The calculated results indicate that the significant pore coarsening and mean pore density decrease in the HBS occur upon surpassing a local burn-up of 100 GWd/tM. The capability of this model is successfully validated against irradiation experiments of UO2 fuel, in which the average pore radius, pore density, and porosity are directly measured as functions of local burn-up. Comparisons with experimental data show that, when the local burn-up exceeds 100 GWd/tM, the calculated results agree well with the measured data.

  17. Benefits of the delta K of depletion benchmarks for burnup credit validation

    Energy Technology Data Exchange (ETDEWEB)

    Lancaster, D. [NuclearConsultants.com, 187 Faith Circle, Boalsburg, PA 16827 (United States); Machiels, A. [Electric Power Research Inst., Inc., 3420 Hillview Avenue, Palo Alto, CA 94304 (United States)

    2012-07-01

    Pressurized Water Reactor (PWR) burnup credit validation is demonstrated using the benchmarks for quantifying fuel reactivity decrements, published as 'Benchmarks for Quantifying Fuel Reactivity Depletion Uncertainty,' EPRI Report 1022909 (August 2011). This demonstration uses the depletion module TRITON available in the SCALE 6.1 code system followed by criticality calculations using KENO-Va. The difference between the predicted depletion reactivity and the benchmark's depletion reactivity is a bias for the criticality calculations. The uncertainty in the benchmarks is the depletion reactivity uncertainty. This depletion bias and uncertainty is used with the bias and uncertainty from fresh UO{sub 2} critical experiments to determine the criticality safety limits on the neutron multiplication factor, k{sub eff}. The analysis shows that SCALE 6.1 with the ENDF/B-VII 238-group cross section library supports the use of a depletion bias of only 0.0015 in delta k if cooling is ignored and 0.0025 if cooling is credited. The uncertainty in the depletion bias is 0.0064. Reliance on the ENDF/B V cross section library produces much larger disagreement with the benchmarks. The analysis covers numerous combinations of depletion and criticality options. In all cases, the historical uncertainty of 5% of the delta k of depletion ('Kopp memo') was shown to be conservative for fuel with more than 30 GWD/MTU burnup. Since this historically assumed burnup uncertainty is not a function of burnup, the Kopp memo's recommended bias and uncertainty may be exceeded at low burnups, but its absolute magnitude is small. (authors)

  18. Effect of Control Blade History, and Axial Coolant Density and Burnup Profiles on BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J [ORNL; Marshall, William BJ J [ORNL; Martinez-Gonzalez, Jesus S [ORNL

    2015-05-01

    Oak Ridge National Laboratory (ORNL) and the US Nuclear Regulatory Commission (NRC) have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling water reactor (BWR) fuel in storage and transportation systems (often referred to as casks) and spent fuel pools (SFPs). This work is divided into two main phases. The first phase investigated the applicability of peak reactivity methods currently used in SFPs to transportation and storage casks and the validation of reactivity calculations and spent fuel compositions within these methods. The second phase focuses on extending BUC beyond peak reactivity. This paper documents the analysis of the effects of control blade insertion history, and moderator density and burnup axial profiles for extended BWR BUC.

  19. Investigation and basic evaluation for ultra-high burnup fuel cladding material

    Energy Technology Data Exchange (ETDEWEB)

    Ioka, Ikuo; Nagase, Fumihisa; Futakawa, Masatoshi; Kiuchi, Kiyoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Suga, Masataka [Kokan Keisoku Co., Kawasaki, Kanagawa (Japan)

    2001-03-01

    In ultra-high burnup of the power reactor, it is an essential problem to develop the cladding with excellent durability. First, development history and approach of the safety assessment of Zircaloy for the high burnup fuel were summarized in the report. Second, the basic evaluation and investigation were carried out on the material with high practicability in order to select the candidate materials for the ultra-high burnup fuel. In addition, the basic research on modification technology of the cladding surface was carried out from the viewpoint of the addition of safety margin as a cladding. From the development history of the zirconium alloy including the Zircaloy, it is hard to estimate the results of in-pile test from those of the conventional corrosion test (out-pile test). Therefore, the development of the new testing technology that can simulate the actual environment and the elucidation of the corrosion-controlling factor of the cladding are desired. In cases of RIA (Reactivity Initiated Accident) and LOCA (Loss of Coolant Accident), it seems that the loss of ductility in zirconium alloys under heavy irradiation and boiling of high temperature water restricts the extension of fuel burnup. From preliminary evaluation on the high corrosion-resistance materials (austenitic stainless steel, iron or nickel base superalloys, titanium alloy, niobium alloy, vanadium alloy and ferritic stainless steel), stabilized austenitic stainless steels with a capability of future improvement and high-purity niobium alloys with a expectation of the good corrosion resistance were selected as candidate materials of ultra-high burnup cladding. (author)

  20. Propagation of statistical and nuclear data uncertainties in Monte Carlo burn-up calculations

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Herranz, Nuria [Departamento de Ingenieria Nuclear, Universidad Politecnica de Madrid, UPM (Spain)], E-mail: nuria@din.upm.es; Cabellos, Oscar [Departamento de Ingenieria Nuclear, Universidad Politecnica de Madrid, UPM (Spain); Sanz, Javier [Departamento de Ingenieria Energetica, Universidad Nacional de Educacion a Distancia, UNED (Spain); Juan, Jesus [Laboratorio de Estadistica, Universidad Politecnica de Madrid, UPM (Spain); Kuijper, Jim C. [NRG - Fuels, Actinides and Isotopes Group, Petten (Netherlands)

    2008-04-15

    Two methodologies to propagate the uncertainties on the nuclide inventory in combined Monte Carlo-spectrum and burn-up calculations are presented, based on sensitivity/uncertainty and random sampling techniques (uncertainty Monte Carlo method). Both enable the assessment of the impact of uncertainties in the nuclear data as well as uncertainties due to the statistical nature of the Monte Carlo neutron transport calculation. The methodologies are implemented in our MCNP-ACAB system, which combines the neutron transport code MCNP-4C and the inventory code ACAB. A high burn-up benchmark problem is used to test the MCNP-ACAB performance in inventory predictions, with no uncertainties. A good agreement is found with the results of other participants. This benchmark problem is also used to assess the impact of nuclear data uncertainties and statistical flux errors in high burn-up applications. A detailed calculation is performed to evaluate the effect of cross-section uncertainties in the inventory prediction, taking into account the temporal evolution of the neutron flux level and spectrum. Very large uncertainties are found at the unusually high burn-up of this exercise (800 MWd/kgHM). To compare the impact of the statistical errors in the calculated flux with respect to the cross uncertainties, a simplified problem is considered, taking a constant neutron flux level and spectrum. It is shown that, provided that the flux statistical deviations in the Monte Carlo transport calculation do not exceed a given value, the effect of the flux errors in the calculated isotopic inventory are negligible (even at very high burn-up) compared to the effect of the large cross-section uncertainties available at present in the data files.

  1. Compound effects of operating parameters on burnup credit criticality analysis in boiling water reactor spent fuel assemblies

    Directory of Open Access Journals (Sweden)

    Shang-Chien Wu

    2018-02-01

    Full Text Available This study proposes a new method of analyzing the burnup credit in boiling water reactor spent fuel assemblies against various operating parameters. The operating parameters under investigation include fuel temperature, axial burnup profile, axial moderator density profile, and control blade usage. In particular, the effects of variations in one and two operating parameters on the curve of effective multiplication factor (keff versus burnup (B are, respectively, the so-called single and compound effects. All the calculations were performed using SCALE 6.1 together with the Evaluated Nuclear Data Files, part B (ENDF/B-VII238-neutron energy group data library. Furthermore, two geometrical models were established based on the General Electric (GE14 10 × 10 boiling water reactor fuel assembly and the Generic Burnup-Credit (GBC-68 storage cask. The results revealed that the curves of keff versus B, due to single and compound effects, can be approximated using a first degree polynomial of B. However, the reactivity deviation (or changes of keff,Δk in some compound effects was not a summation of the all Δk resulting from the two associated single effects. This phenomenon is undesirable because it may to some extent affect the precise assessment of burnup credit. In this study, a general formula was thus proposed to express the curves of keff versus B for both single and compound effects.

  2. Evaluation of the Frequency for Gas Sampling for the High Burnup Confirmatory Data Project

    Energy Technology Data Exchange (ETDEWEB)

    Stockman, Christine T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Alsaed, Halim A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Marschman, Steven C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Scaglione, John M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-05-01

    This report provides a technically based gas sampling frequency strategy for the High Burnup (HBU) Confirmatory Data Project. The evaluation of: 1) the types and magnitudes of gases that could be present in the project cask and, 2) the degradation mechanisms that could change gas compositions culminates in an adaptive gas sampling frequency strategy. This adaptive strategy is compared against the sampling frequency that has been developed based on operational considerations.

  3. Advanced Corrosion-Resistant Zr Alloys for High Burnup and Generation IV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Arthur Motta; Yong Hwan Jeong; R.J. Comstock; G.S. Was; Y.S. Kim

    2006-10-31

    The objective of this collaboration between four institutions in the US and Korea is to demonstrate a technical basis for the improvement of the corrosion resistance of zirconium-based alloys in more extreme operating environments (such as those present in severe fuel duty,cycles (high burnup, boiling, aggressive chemistry) andto investigate the feasibility (from the point of view of corrosion rate) of using advanced zirconium-based alloys in a supercritical water environment.

  4. Influence of FIMA burnup on actinides concentrations in PWR reactors

    Directory of Open Access Journals (Sweden)

    Oettingen Mikołaj

    2016-01-01

    Full Text Available In the paper we present the study on the dependence of actinides concentrations in the spent nuclear fuel on FIMA burnup. The concentrations of uranium, plutonium, americium and curium isotopes obtained in numerical simulation are compared with the result of the post irradiation assay of two spent fuel samples. The samples were cut from the fuel rod irradiated during two reactor cycles in the Japanese Ohi-2 Pressurized Water Reactor. The performed comparative analysis assesses the reliability of the developed numerical set-up, especially in terms of the system normalization to the measured FIMA burnup. The numerical simulations were preformed using the burnup and radiation transport mode of the Monte Carlo Continuous Energy Burnup Code – MCB, developed at the Department of Nuclear Energy, Faculty of Energy and Fuels of AGH University of Science and Technology.

  5. A guide introducing burnup credit, preliminary version. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    It is examined to take burnup credit into account for criticality safety control of facility treating spent fuel. This work is a collection of current technical status of predicting isotopic composition and criticality of spent fuel, points to be specially considered for safety evaluation, and current status of legal affairs for the purpose of applying burnup credit to the criticality safety evaluation of the facility treating spent fuel in Japan. (author)

  6. Designing Critical Experiments in Support of Full Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Roberts, Jeremy A [ORNL

    2008-01-01

    Burnup credit is the process of accounting for the negative reactivity due to fuel burnup and generation of parasitic absorbers over fuel assembly lifetime. For years, the fresh fuel assumption was used as a simple bound in criticality work for used fuel storage and transportation. More recently, major actinides have been included [1]. However, even this yields a highly conservative estimate in criticality calculations. Because of the numerous economical benefits including all available negative reactivity (i.e., full burnup credit) could provide [2], it is advantageous to work toward full burnup credit. Unfortunately, comparatively little work has been done to include non-major actinides and other fission products (FP) in burnup credit analyses due in part to insufficient experimental data for validation of codes and nuclear data. The Burnup Credit Criticality Experiment (BUCCX) at Sandia National Laboratory was a set of experiments with {sup 103}Rh that have relevance for burnup credit [3]. This work uses TSUNAMI-3D to investigate and adjust a BUCCX model to match isotope-specific, energy-dependent k{sub eff} sensitivity profiles to those of a representative high-capacity cask model (GBC-32) [4] for each FP of interest. The isotopes considered are {sup 149}Sm, {sup 143}Nd, {sup 103}Rh, {sup 133}Cs, {sup 155}Gd, {sup 152}Sm, {sup 99}Tc, {sup 145}Nd, {sup 153}Eu, {sup 147}Sm, {sup 109}Ag, {sup 95}Mo, {sup 150}Sm, {sup 101}Ru, and {sup 151}Eu. The goal is to understand the biases and bias uncertainties inherent in nuclear data, and ultimately, to apply these in support of full burnup credit.

  7. Draft evaluation of the frequency for gas sampling for the high burnup confirmatory data project

    Energy Technology Data Exchange (ETDEWEB)

    Stockman, Christine T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Alsaed, Halim A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-26

    This report fulfills the M3 milestone M3FT-15SN0802041, “Draft Evaluation of the Frequency for Gas Sampling for the High Burn-up Storage Demonstration Project” under Work Package FT-15SN080204, “ST Field Demonstration Support – SNL”. This report provides a technically based gas sampling frequency strategy for the High Burnup (HBU) Confirmatory Data Project. The evaluation of: 1) the types and magnitudes of gases that could be present in the project cask and, 2) the degradation mechanisms that could change gas compositions culminates in an adaptive gas sampling frequency strategy. This adaptive strategy is compared against the sampling frequency that has been developed based on operational considerations. Gas sampling will provide information on the presence of residual water (and byproducts associated with its reactions and decomposition) and breach of cladding, which could inform the decision of when to open the project cask.

  8. Coolant Density and Control Blade History Effects in Extended BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J [ORNL; Marshall, William BJ J [ORNL; Bowman, Stephen M [ORNL; Gauld, Ian C [ORNL; Ilas, Germina [ORNL; Martinez-Gonzalez, Jesus S [ORNL

    2015-01-01

    Oak Ridge National Laboratory and the US Nuclear Regulatory Commission have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase investigates the applicability of peak reactivity methods currently used for spent fuel pools to spent fuel storage and transportation casks and the validation of reactivity (keff) calculations and predicted spent fuel compositions. The second phase focuses on extending BUC beyond peak reactivity. This paper documents work performed to date investigating some aspects of extended BUC. (The technical basis for application of peak reactivity methods to BWR fuel in storage and transportation systems is presented in a companion paper.) Two reactor operating parameters are being evaluated to establish an adequate basis for extended BWR BUC: (1) the effect of axial void profile and (2) the effect of control blade utilization during operation. A detailed analysis of core simulator data for one cycle of a modern operating BWR plant was performed to determine the range of void profiles and the variability of the profile experienced during irradiation. Although a single cycle does not provide complete data, the data obtained are sufficient to determine the primary effects and to identify conservative modeling approaches. These data were used in a study of the effect of axial void profile. The first stage of the study was determination of the necessary moderator density temporal fidelity in depletion modeling. After the required temporal fidelity was established, multiple void profiles were used to examine the effect on cask reactivity. The results of these studies are being used to develop recommendations for conservatively modeling the void profile effects for BWR depletion calculations. The second operational parameter studied was control blade history. Control blades are inserted in

  9. Extended Burnup Credit for BWR Spent Nuclear Fuel in Storage and Transportation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bowman, Stephen M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gauld, Ian C [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ilas, Germina [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Martinez, J. S. [Univ. Politecnica de Madrid (Spain). Dept. of Nuclear Engineering

    2015-01-01

    [Full Text] Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling-water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase investigates the applicability of peak reactivity methods currently used for spent fuel pools to spent fuel storage and transportation casks and the validation of reactivity (keff) calculations and depleted fuel compositions. The second phase focuses on extending BUC beyond peak reactivity. This paper documents work performed to date, investigating some aspects of extended BUC, and it also describes the plan to complete the evaluations. The technical basis for application of peak reactivity methods to BWR fuel in storage and transportation systems is presented in a companion paper. Two reactor operating parameters are being evaluated to establish an adequate basis for extended BWR BUC, including investigation of the axial void profile effect and the effect of control blade utilization during operation. A detailed analysis of core simulator data for one cycle of an operating BWR plant was performed to determine the range of void profiles and the variability of the profile experienced during irradiation. While a single cycle does not provide complete data, the data obtained are sufficient to use to determine the primary effects and identify conservative modeling approaches. Using data resulting from a single cycle, the axial void profile is studied by first determining the temporal fidelity necessary in depletion modeling, and then using multiple void profiles to examine the effect of the void profile on cask reactivity. The results of these studies are being used to develop recommendations for conservatively modeling the void profile effects for BWR depletion calculations. The second operational parameter studied is control blade exposure. Control blades

  10. MOX fuel characterization for burnup credit application: Extension of nondestructive method qualified for LEU fuels

    Energy Technology Data Exchange (ETDEWEB)

    Riffard, C.; Vidal, J.M. [Commissariat a l' Energie Atomique CEA/DEN/CAD, Building 230 Centre d tudes de Cadarache, 13108 St. Paul Lez Durance (France); Toubon, H. [COGEMA, 78 141 Velizy cedex (France); Pelletter, S. [Canberra-Eurisys, 78067 St. Quentin en Yvelines cedex (France); Batifol, M. [COGEMA La Hague, 50444 Beaumont Hague cedex (France)

    2006-07-01

    Before the reprocessing of low-enriched uranium (LEU) fuels at La. Hague plant, the assemblies are characterized with a nondestructive assay based on neutron emission (NE) and gamma-ray emission combined with the CESAR depletion code, giving the burnup (BU) with a good accuracy ({+-} 5% within a batch of fuels from one of COGEMA-La Hague's clients). The measurements confirm the hypothesis of the safety-criticality analysis of the process, in the context of the BU credit allowance. There is a need to extend the allowance of the reprocessing plants to the case of more highly enriched LEU fuels and to the case of mixed-oxide (MOX) fuels. The aim is to propose an upgraded method, valid for both LEU and MOX fuels, giving the average BU with an uncertainty lower than {+-} 15% for MOX fuels (without any modification of the current acceptance criteria for UO{sub 2} fuel, i.e. {+-} 15%), with a complementary module checking the operator data using the gamma-ray emission and the CESAR depletion code. In particular, the NE was interpreted with depletion calculations in the case of MOX fuels, which is the principal aim of this paper. This allows the BU determination of MOX fuels, which has been qualified during a measurement campaign in La Hague with 20 MOX assemblies. The mean BU of pressurized water reactor MOX assemblies has been determined for the first time with a maximum discrepancy of {+-} 5% compared to the declared value. (authors)

  11. Criticality Uncertainty Analysis of Spent Fuel Transport Cask applying Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gang Ug; Park, Jae Ho; Kim, Do Hyun [Korea Nuclear Engineering and Service Corp, Daejeon (Korea, Republic of); Kim, Tae Man; Yoon, Jeong Hyun [Korea Radioactive Waste Management Corporation, Daejeon (Korea, Republic of)

    2011-09-15

    In general, conventional criticality analyses for spent fuel transport/dry storage systems have been performed based on assumption of fresh fuel concerning the potential uncertainties from number density calculation of Transuranic and Fission Products in spent fuel. However, because of economic loss due to the excessive criticality margin, recently the design of transport/dry storage systems with Burnup Credit(BUC) application has been actively developed. The uncertainties in criticality analyses on transport/storage systems with BUC technique show strong dependence upon initial enrichment and burnup rate, whereas those in the conventional criticality evaluation based on fresh fuel assumption do not show such a dependence. In this study, regulatory-required uncertainties of the criticality analyses for BK 26 Cask, which is conceptually designed spent fuel transport cask with BUC corresponding to the limiting circumstances on nuclear power plants in Korea, are evaluated as a function of initial enrichment and burnup rate. Results of this study will be used as basic data for spent fuel loading curve of BK 26 Cask.

  12. EPRI/DOE High Burnup Fuel Sister Pin Test Plan Simplification and Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Saltzstein, Sylvia J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorenson, Ken B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hanson, Brady [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billone, Mike [Argonne National Lab. (ANL), Argonne, IL (United States); Scaglione, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    The EPRI/DOE High Burnup Confirmatory Data Project (herein called the "Demo") is a multi-year, multi-entity confirmation demonstration test with the purpose of providing quantitative and qualitative data to show how high-burnup fuel ages in dry storage over a ten-year period. The Demo involves obtaining 32 assemblies of high-burnup PWR fuel of four common cladding alloys from the North Anna Nuclear Power Plant, drying them according to standard plant procedures, and then storing them in an NRC-licensed TN-3 2B cask on the North Anna dry storage pad for ten years. After the ten-year storage time, the cask will be opened and the rods will be examined for signs of aging. Twenty-five rods from assemblies of similar claddings, in-reactor placement, and burnup histories (herein called "sister rods") have been shipped from the North Anna Nuclear Power Plant and are currently being nondestructively tested at Oak Ridge National Laboratory. After the non-destructive testing has been completed for each of the twenty-five rods, destructive analysis will be performed at ORNL, PNNL, and ANL to obtain mechanical data. Opinions gathered from the expert interviews, ORNL and PNNL Sister Rod Test Plans, and numerous meetings has resulted in the Simplified Test Plan described in this document. Some of the opinions and discussions leading to the simplified test plan are included here. Detailed descriptions and background are in the ORNL and PNNL plans in the appendices . After the testing described in this simplified test plan h as been completed , the community will review all the collected data and determine if additional testing is needed.

  13. Preparation of higher-actinide burnup and cross section samples. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Adair, H.L.; Kobisk, E.H.; Quinby, T.C.; Thomas, D.K.; Dailey, J.M.

    1981-01-01

    A joint research program involving the United States and the United Kingdom was instigated about four years ago for the purpose of studying burnup of higher actinides using in-core irradiation in the fast reactor at Dounreay, Scotland. Simultaneously, determination of cross sections of a wide variety of higher actinide isotopes was proposed. Coincidental neutron flux and energy spectral measurements were to be made using vanadium encapsulated dosimetry materials in the immediate region of the burnup and cross section samples. The higher actinide samples chosen for the burnup study were /sup 241/Am and /sup 244/Cm in the forms of Am/sub 2/O/sub 3/, Cm/sub 2/O/sub 3/, and Am/sub 6/ Cm(RE)/sub 7/O/sub 21/, where (RE) represents a mixture of lanthanide sesquioxides. It is the purpose of this paper to describe technology development and its application in the preparation of the fuel specimens and the cross section specimens that are being used in this cooperative program.

  14. Burn-up credit in criticality safety of PWR spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoud, Rowayda F., E-mail: Rowayda_mahmoud@yahoo.com [Metallurgy Department, Nuclear Research Center, Atomic Energy Authority (Egypt); Shaat, Mohamed K. [Nuclear Engineering, Reactors Department, Nuclear Research Center, Atomic Energy Authority (Egypt); Nagy, M.E.; Agamy, S.A. [Professor of Nuclear Engineering, Nuclear and Radiation Department, Alexandria University (Egypt); Abdelrahman, Adel A. [Metallurgy Department, Nuclear Research Center, Atomic Energy Authority (Egypt)

    2014-12-15

    Highlights: • Designing spent fuel wet storage using WIMS-5D and MCNP-5 code. • Studying fresh and burned fuel with/out absorber like “B{sub 4}C and Ag–In–Cd” in racks. • Sub-criticality was confirmed for fresh and burned fuel under specific cases. • Studies for BU credit recommend increasing fuel burn-up to 60.0 GWD/MTU. • Those studies require new core structure materials, fuel composition and cladding. - Abstract: The criticality safety calculations were performed for a proposed design of a wet spent fuel storage pool. This pool will be used for the storage of spent fuel discharged from a typical pressurized water reactor (PWR). The mathematical model based on the international validated codes, WIMS-5 and MCNP-5 were used for calculating the effective multiplication factor, k{sub eff}, for the spent fuel stored in the pool. The data library for the multi-group neutron microscopic cross-sections was used for the cell calculations. The k{sub eff} was calculated for several changes in water density, water level, assembly pitch and burn-up with different initial fuel enrichment and new types and amounts of fixed absorbers. Also, k{sub eff} was calculated for the conservative fresh fuel case. The results of the calculations confirmed that the effective multiplication factor for the spent fuel storage is sub-critical for all normal and abnormal states. The future strategy for the burn-up credit recommends increasing the fuel burn-up to a value >60.0 GWD/MTU, which requires new fuel composition and new fuel cladding material with the assessment of the effects of negative reactivity build up.

  15. Analysis of the effect of UO{sub 2} high burnup microstructure on fission gas release

    Energy Technology Data Exchange (ETDEWEB)

    Jernkvist, Lars Olof; Massih, Ali [Quantum Technologies AB, Uppsala Science Park (Sweden)

    2002-10-01

    This report deals with high-burnup phenomena with relevance to fission gas release from UO{sub 2} nuclear fuel. In particular, we study how the fission gas release is affected by local buildup of fissile plutonium isotopes and fission products at the fuel pellet periphery, with subsequent formation of a characteristic high-burnup rim zone micro-structure. An important aspect of these high-burnup effects is the degradation of fuel thermal conductivity, for which prevalent models are analysed and compared with respect to their theoretical bases and supporting experimental data. Moreover, the Halden IFA-429/519.9 high-burnup experiment is analysed by use of the FRAPCON3 computer code, into which modified and extended models for fission gas release are introduced. These models account for the change in Xe/Kr-ratio of produced and released fission gas with respect to time and space. In addition, several alternative correlations for fuel thermal conductivity are implemented, and their impact on calculated fission gas release is studied. The calculated fission gas release fraction in IFA-429/519.9 strongly depends on what correlation is used for the fuel thermal conductivity, since thermal release dominates over athermal release in this particular experiment. The conducted calculations show that athermal release processes account for less than 10% of the total gas release. However, athermal release from the fuel pellet rim zone is presumably underestimated by our models. This conclusion is corroborated by comparisons between measured and calculated Xe/Kr-ratios of the released fission gas.

  16. The interest of burnup increase in a context of recycling

    Energy Technology Data Exchange (ETDEWEB)

    Druenne, Hubert [GDF SUEZ-TRACTEBEL, Avenue Ariane 7 - B-1200 Brussels (Belgium)

    2009-06-15

    The current trend is to increase the fuel discharge burnup. In the framework of a recycling policy (closed cycle) higher burnup also affects the quality of the fissile material coming back from the reprocessing. It has the following consequences: - the lower quality of the reprocessed material requires either higher ERU enrichment and/or higher plutonium content in MOX fuel; - should some limits be reached (manufacture limits, maximum {sup 235}U enrichment or Pu content), the energy equivalence could no longer be maintained between recycled fuel assemblies (ERU or MOX) and ENU ones; - in turn, the loss of energy equivalence would request larger feed size, and hence would limit the burnup increase. Consequently, the question is whether an increase in burnup could hamper a recycling policy. In a closed cycle, and considering only the 2. or 3. generation PWR, does the increase in burnup still make it possible to reduce the need for fissile material? Is there an economic optimum? This paper attempts to answer these questions. In conclusions: A. Reprocessing and recycling processes: The present industrial processes technical limits do not hinder reprocessing and recycling of highly burned assemblies (at least in the assumed limit of roughly 65 GWd/t - assembly average). But taking into account the present limitations in terms of initial enrichment, enrichment technology, fuel fabrication and fresh fuel transportation, the additional costs may limit or even over-compensate the benefits resulting from higher discharge burnups. These costs must be known to conclude on the economy of high burnup in a closed cycle policy. B. In-core fuel management: In 18-month cycle, the present 5% enrichment limit is a strong constraint for 'auto-recycling': even with the shortest reprocessing delays as possible, it restricts the achievable batch average discharge burnup to about 56 GWd/t. The economy of high burnup should be analysed in a multi nuclear unit fuel management, with

  17. Study on nuclear physics of high burn-up full MOX-BWR core

    Energy Technology Data Exchange (ETDEWEB)

    Shirakawa, Toshihisa; Okubo, Tsutomu; Ochiai, Masa-aki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-08-01

    In this report, neutronics study of full Mixed-oxide (MOX) high burn-up BWR core is presented. Our design goals are about 3-year cycle length, four-batch refueling scheme and more than 100GWd/t fuel discharge burn-up. Base core configuration is 1,350MWe US version of ABWR with 9 x 9 type fuel assembly. Investigation of the reactor core has been carried out by arranging Gd{sub 2}O{sub 3} contents in fuel rods and changing water to fuel volume ratio (V{sub m}/V{sub f}) through the number of water rods or adjustment of fuel clad diameter. JAERI`s general purpose neutronics code system SRAC95 was used for two dimensional XY fuel assembly cell neutronics calculations. Calculated cases are for a comparatively high moderated fuel assembly with 9 water rods, a fuel assembly without water rods and a comparatively low moderated fuel assembly without water rods and with larger fuel clad diameter. All these 3 cases seem to achieve our design goals mentioned above. For the last case, three dimensional core burn-up calculation was performed by this code system. This case seems to attain a low linear power density and the operation with all control rod out. (author)

  18. Advances in Metallic Fuels for High Burnup and Actinide Transmutation

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, S. L.; Harp, J. M.; Chichester, H. J. M.; Fielding, R. S.; Mariani, R. D.; Carmack, W. J.

    2016-10-01

    Research and development activities on metallic fuels in the US are focused on their potential use for actinide transmutation in future sodium fast reactors. As part of this application, there is a desire to demonstrate a multifold increase in burnup potential. A number of metallic fuel design innovations are under investigation with a view toward significantly increasing the burnup potential of metallic fuels, since higher discharge burnups equate to lower potential actinide losses during recycle. Promising innovations under investigation include: 1) lowering the fuel smeared density in order to accommodate the additional swelling expected as burnups increase, 2) utilizing an annular fuel geometry for better geometrical stability at low smeared densities, as well as the potential to eliminate the need for a sodium bond, and 3) minor alloy additions to immobilize lanthanide fission products inside the metallic fuel matrix and prevent their transport to the cladding resulting in fuel-cladding chemical interaction. This paper presents results from these efforts to advance metallic fuel technology in support of high burnup and actinide transmutation objectives. Highlights include examples of fabrication of low smeared density annular metallic fuels, experiments to identify alloy additions effective in immobilizing lanthanide fission products, and early postirradiation examinations of annular metallic fuels having low smeared densities and palladium additions for fission product immobilization.

  19. Modeling of pore coarsening in the rim region of high burn-up UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Hongxing; Long, Chong Sheng [Science and Technology on Reactor Fuel and Materials Laboratory, Nuclear Power Institute of China, Chengdu (China)

    2016-08-15

    An understanding of the coarsening process of the large fission gas pores in the high burn-up structure (HBS) of irradiated UO{sub 2} fuel is very necessary for analyzing the safety and reliability of fuel rods in a reactor. A numerical model for the description of pore coarsening in the HBS based on the Ostwald ripening mechanism, which has successfully explained the coarsening process of precipitates in solids is developed. In this model, the fission gas atoms are treated as the special precipitates in the irradiated UO{sub 2} fuel matrix. The calculated results indicate that the significant pore coarsening and mean pore density decrease in the HBS occur upon surpassing a local burn-up of 100 GWd/tM. The capability of this model is successfully validated against irradiation experiments of UO{sub 2} fuel, in which the average pore radius, pore density, and porosity are directly measured as functions of local burn-up. Comparisons with experimental data show that, when the local burn-up exceeds 100 GWd/tM, the calculated results agree well with the measured data.

  20. Critical assessment of the pore size distribution in the rim region of high burnup UO{sub 2} fuels

    Energy Technology Data Exchange (ETDEWEB)

    Cappia, F. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Nuclear Engineering, Faculty of Mechanical Engineering, Technische Universität München, D-85748 Garching bei München (Germany); Pizzocri, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Nuclear Engineering Division, Energy Department, Politecnico di Milano, 20156 Milano (Italy); Schubert, A.; Van Uffelen, P.; Paperini, G.; Pellottiero, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Macián-Juan, R. [Department of Nuclear Engineering, Faculty of Mechanical Engineering, Technische Universität München, D-85748 Garching bei München (Germany); Rondinella, V.V., E-mail: Vincenzo.RONDINELLA@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany)

    2016-11-15

    A new methodology is introduced to analyse porosity data in the high burnup structure. Image analysis is coupled with the adaptive kernel density estimator to obtain a detailed characterisation of the pore size distribution, without a-priori assumption on the functional form of the distribution. Subsequently, stereological analysis is carried out. The method shows advantages compared to the classical approach based on the histogram in terms of detail in the description and accuracy within the experimental limits. Results are compared to the approximation of a log-normal distribution. In the investigated local burnup range (80–200 GWd/tHM), the agreement of the two approaches is satisfactory. From the obtained total pore density and mean pore diameter as a function of local burnup, pore coarsening is observed starting from ≈100 GWd/tHM, in agreement with a previous investigation. - Highlights: • A new methodology to analyse porosity is introduced. • The method shows advantages compared to the histogram. • Pore density and mean diameter data vs. burnup are presented. • Pore coarsening is observed starting from ≈100 GWd/tHM.

  1. Effects of Lower Drying-Storage Temperature on the Ductility of High-Burnup PWR Cladding

    Energy Technology Data Exchange (ETDEWEB)

    Billone, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Burtseva, T. A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-08-30

    The purpose of this research effort is to determine the effects of canister and/or cask drying and storage on radial hydride precipitation in, and potential embrittlement of, high-burnup (HBU) pressurized water reactor (PWR) cladding alloys during cooling for a range of peak drying-storage temperatures (PCT) and hoop stresses. Extensive precipitation of radial hydrides could lower the failure hoop stresses and strains, relative to limits established for as-irradiated cladding from discharged fuel rods stored in pools, at temperatures below the ductile-to-brittle transition temperature (DBTT).

  2. Validation of depletion codes for burnup credit evaluation of LWR assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Ranta-aho, A. [Technical Research Centre of Finland VTT, POB 1000, 02044-VTT (Finland)

    2006-07-01

    This paper reports the comparison of the CASMO-4E predictions with the radiochemical assay data from assemblies irradiated in Takahama-3 PWR and Fukushima-Daini-2 BWR, and the most recently reported spent fuel data from the VVER-440 assembly irradiated in Novovoronezh 4. Some of the calculations were repeated with the ABURN burnup code, which is a combination of the MCNP4C Monte Carlo code and the ORIGEN2 depletion code. The cross section libraries applied were based on the ENDF/B-VI and the JEF-2.2 data. (authors)

  3. Monte Carlo burnup code acceleration with the correlated sampling method. Preliminary test on an UOX cell with TRIPOLI-4{sup R}

    Energy Technology Data Exchange (ETDEWEB)

    Dieudonne, C.; Dumonteil, E.; Malvagi, F.; Diop, C. M. [Commissariat a l' Energie Atomique et aux Energies Alternatives CEA, Service d' Etude des Reacteurs et de Mathematiques Appliquees, DEN/DANS/DM2S/SERMA/LTSD, F91191 Gif-sur-Yvette cedex (France)

    2013-07-01

    For several years, Monte Carlo burnup/depletion codes have appeared, which couple a Monte Carlo code to simulate the neutron transport to a deterministic method that computes the medium depletion due to the neutron flux. Solving Boltzmann and Bateman equations in such a way allows to track fine 3 dimensional effects and to get rid of multi-group hypotheses done by deterministic solvers. The counterpart is the prohibitive calculation time due to the time-expensive Monte Carlo solver called at each time step. Therefore, great improvements in term of calculation time could be expected if one could get rid of Monte Carlo transport sequences. For example, it may seem interesting to run an initial Monte Carlo simulation only once, for the first time/burnup step, and then to use the concentration perturbation capability of the Monte Carlo code to replace the other time/burnup steps (the different burnup steps are seen like perturbations of the concentrations of the initial burnup step). This paper presents some advantages and limitations of this technique and preliminary results in terms of speed up and figure of merit. Finally, we will detail different possible calculation scheme based on that method. (authors)

  4. A VVER-1000 LEU and MOX assembly computational benchmark analysis using the lattice burnup code EXCEL

    Energy Technology Data Exchange (ETDEWEB)

    Thilagam, L. [AERB-Safety Research Institute, Kalpakkam, Tamilnadu 603 102 (India)], E-mail: thilagam@igcar.gov.in; Sunil Sunny, C. [AERB-Safety Research Institute, Kalpakkam, Tamilnadu 603 102 (India); Jagannathan, V. [Light Water Reactor Physics Section, Reactor Physics Design Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)], E-mail: v_jagan1952@rediffmail.com; Subbaiah, K.V. [AERB-Safety Research Institute, Kalpakkam, Tamilnadu 603 102 (India)

    2009-05-01

    Utilization of Mixed Uranium-Plutonium Oxide (MOX) fuel in VVER-1000 reactors envisages the core physics analysis using computational methods and validation of the related computer codes. Towards this objective, an international experts group has been established at OECD/NEA. The experts group facilitates sharing of existing information on physics parameters and fuel behaviour. Several benchmark exercises have been proposed by them with intent to investigate the core physics behaviour of a VVER-1000 reactor loaded with 2/3rd of low enriched uranium (LEU) fuel assemblies (FA) and 1/3rd of weapons grade mixed oxide (MOX) FA. In the present study an attempt is made to analyse 'AVVER-1000LEUandMOXAssemblyComputationalBenchmark' and predict the neutronics behaviour at the lattice level. The lattice burnup code EXCEL, developed at Light Water Reactor Physics Section, BARC is employed for this task. The EXCEL code uses the 172 energy group 'JEFF31GX' cross-section library in WIMS-D format. Assembly level fuel depletion calculations are performed up to a burnup of 40 MWD/kg of heavy metal (HM). Studies are made for the parametric variations of fuel and moderator temperatures, coolant density and boron content in the coolant. Both operational and off-normal states are analysed to determine the corresponding infinite neutron multiplication factor (k{sub {infinity}}). Pin wise isotopic compositions are computed as a function of burnup. Isotopic compositions in different annular regions of Uranium-Gadolinium (UGD) pin, fission rate distributions in UGD, UO{sub 2} and MOX pin cells are also computed. The predicted results are compared with the benchmark mean results.

  5. SENSITIVITY AND UNCERTAINTY ANALYSIS OF COMMERCIAL REACTOR CRITICALS FOR BURNUP CREDIT

    Energy Technology Data Exchange (ETDEWEB)

    Radulescu, Georgeta [ORNL; Mueller, Don [ORNL; Wagner, John C [ORNL

    2009-01-01

    The purpose of this study is to provide insights into the neutronic similarities that may exist between a generic cask containing typical spent nuclear fuel assemblies and commercial reactor critical (CRC) state-points. Forty CRC state-points from five pressurized-water reactors were selected for the study and the type of CRC state-points that may be applicable for validation of burnup credit criticality safety calculations for spent fuel transport/storage/disposal systems are identified. The study employed cross-section sensitivity and uncertainty analysis methods developed at Oak Ridge National Laboratory and the TSUNAMI set of tools in the SCALE code system as a means to investigate system similarity on an integral and nuclide-reaction specific level. The results indicate that, except for the fresh fuel core configuration, all analyzed CRC state-points are either highly similar, similar, or marginally similar to a generic cask containing spent nuclear fuel assemblies with burnups ranging from 10 to 60 GWd/MTU. Based on the integral system parameter, C{sub k}, approximately 30 of the 40 CRC state-points are applicable to validation of burnup credit in the generic cask containing typical spent fuel assemblies with burnups ranging from 10 to 60 GWd/MTU. The state-points providing the highest similarity (C{sub k} > 0.95) were attained at or near the end of a reactor cycle. The C{sub k} values are dominated by neutron reactions with major actinides and hydrogen, as the sensitivities of these reactions are much higher than those of the minor actinides and fission products. On a nuclide-reaction specific level, the CRC state-points provide significant similarity for most of the actinides and fission products relevant to burnup credit. A comparison of energy-dependent sensitivity profiles shows a slight shift of the CRC K{sub eff} sensitivity profiles toward higher energies in the thermal region as compared to the K{sub eff} sensitivity profile of the generic cask

  6. Burnup calculations using serpent code in accelerator driven thorium reactors

    Energy Technology Data Exchange (ETDEWEB)

    Korkmaz, M.E.; Agar, O. [Karamanoglu Mehmetbey Univ., Karaman (Turkey). Physics Dept.; Yigit, M. [Aksaray Univ. (Turkey). Physics Dept.

    2013-07-15

    In this study, burnup calculations have been performed for a sodium cooled Accelerator Driven Thorium Reactor (ADTR) using the Serpent 1.1.16 Monte Carlo code. The ADTR has been designed for burning minor actinides, mixed {sup 232}Th and mixed {sup 233}U fuels. A solid Pb-Bi spallation target in the center of the core is used and sodium as coolant. The system is designed for a heating power of 2 000 MW and for an operation time of 600 days. For burnup calculations the Advanced Matrix Exponential Method CRAM (Chebyshev Rational Approximation Method) and different nuclear data libraries (ENDF7, JEF2.2, JEFF3.1.1) were used. The effective multiplication factor change from 0.93 to 0.97 for different nuclear data libraries during the reactor operation period. (orig.)

  7. Preliminary Content Evaluation of the North Anna High Burn-Up Sister Fuel Rod Segments for Transportation in the 10-160B and NAC-LWT

    Energy Technology Data Exchange (ETDEWEB)

    Ketusky, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-08-09

    The U.S. Department of Energy’s (DOE’s) Used Fuel Disposition Campaign (UFDC) Program has transported high-burnup nuclear sister fuel rods from a commercial nuclear power plant for purposes of evaluation and testing. The evaluation and testing of high-burnup used nuclear fuel is integral to DOE initiatives to collect information useful in determining the integrity of fuel cladding for future safe transportation of the fuel, and for determining the effects of aging, on the integrity of UNF subjected to extended storage and subsequent transportation. The UFDC Program, in collaboration with the U.S. Nuclear Regulatory Commission and the commercial nuclear industry, has obtained individual used nuclear fuel rods for testing. The rods have been received at Oak Ridge National Laboratory (ORNL) for both separate effects testing (SET) and small-scale testing (SST). To meet the research objectives, testing on multiple 6 inch fuel rod pins cut from the rods at ORNL will be performed at Pacific Northwest National Laboratory (PNNL). Up to 10 rod equivalents will be shipped. Options were evaluated for multiple shipments using the 10-160B (based on 4.5 rod equivalents) and a single shipment using the NAC-LWT. Based on the original INL/Virginia Power transfer agreement, the rods are assumed to 152 inches in length with a 0.374-inch diameter. This report provides a preliminary content evaluation for use of the 10-160B and NAC-LWT for transporting those fuel rod pins from ORNL to PNNL. This report documents the acceptability of using these packagings to transport the fuel segments from ORNL to PNNL based on the following evaluations: enrichment, A2 evaluation, Pu-239 FGE evaluation, heat load, shielding (both gamma and neutron), and content weight/structural evaluation.

  8. Addressing Fission Product Validation in MCNP Burnup Credit Criticality Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Bowen, Douglas G [ORNL; Marshall, William BJ J [ORNL

    2015-01-01

    The US Nuclear Regulatory Commission (NRC) Division of Spent Fuel Storage and Transportation issued Interim Staff Guidance (ISG) 8, Revision 3 in September 2012. This ISG provides guidance for NRC staff members’ review of burnup credit (BUC) analyses supporting transport and dry storage of pressurized water reactor spent nuclear fuel (SNF) in casks. The ISG includes guidance for addressing validation of criticality (keff) calculations crediting the presence of a limited set of fission products and minor actinides (FP&MAs). Based on previous work documented in NRC Regulatory Guide (NUREG) Contractor Report (CR)-7109, the ISG recommends that NRC staff members accept the use of either 1.5 or 3% of the FP&MA worth—in addition to bias and bias uncertainty resulting from validation of keff calculations for the major actinides in SNF—to conservatively account for the bias and bias uncertainty associated with the specified unvalidated FP&MAs. The ISG recommends (1) use of 1.5% of the FP&MA worth if a modern version of SCALE and its nuclear data are used and (2) 3% of the FP&MA worth for well qualified, industry standard code systems other than SCALE with the Evaluated Nuclear Data Files, Part B (ENDF/B),-V, ENDF/B-VI, or ENDF/B-VII cross sections libraries. The work presented in this paper provides a basis for extending the use of the 1.5% of the FP&MA worth bias to BUC criticality calculations performed using the Monte Carlo N-Particle (MCNP) code. The extended use of the 1.5% FP&MA worth bias is shown to be acceptable by comparison of FP&MA worths calculated using SCALE and MCNP with ENDF/B-V, -VI, and -VII–based nuclear data. The comparison supports use of the 1.5% FP&MA worth bias when the MCNP code is used for criticality calculations, provided that the cask design is similar to the hypothetical generic BUC-32 cask model and that the credited FP&MA worth is no more than 0.1 Δkeff (ISG-8, Rev. 3, Recommendation 4).

  9. Burnup Credit Approach Used in the Yucca Mountain License Application

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, John M [ORNL; Wagner, John C [ORNL

    2010-01-01

    The United States Department of Energy has submitted a license application (LA) for construction authorization of a deep geologic repository at Yucca Mountain, Nevada. The license application is currently under review by the United States Nuclear Regulatory Commission (NRC). This paper will describe the methodology and approach used in the LA to address the issue of criticality and the role of burnup credit during the postclosure period. The most significant and effective measures for prevention of criticality in the repository include multiple redundant barriers that act to isolate fissionable material from water (which can act as a moderator, corrosive agent, and transporter of fissile material); inherent geometry of waste package internals and waste forms; presence of fixed neutron absorbers in waste package internals; and fuel burnup for commercial spent nuclear fuel. A probabilistic approach has been used to screen criticality from the total system performance assessment. Within the probabilistic approach, criticality is considered an event, and the total probability of a criticality event occurring within 10,000 years of disposal is calculated and compared against the regulatory criterion. The total probability of criticality includes contributions associated with both internal (within waste packages) and external (external to waste packages) criticality for each of the initiating events that could lead to waste package breach. The occurrence of and conditions necessary for criticality in the repository have been thoroughly evaluated using a comprehensive range of parameter distributions. A simplified design-basis modeling approach has been used to evaluate the probability of criticality by using numerous significant and conservative assumptions. Burnup credit is used only for evaluations of in-package configurations and uses a combination of conservative and bounding modeling approximations to ensure conservatism. This paper will review the NRC regulatory

  10. Used Fuel Disposition Campaign - Baseline Studies for Ring Compression Testing of High-Burnup Fuel Cladding

    Energy Technology Data Exchange (ETDEWEB)

    Billone, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Burtseva, T. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Liu, Y. Y. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-11-23

    Structural analyses of high-burnup fuel require cladding mechanical properties and failure limits to assess fuel behavior during long-term dry cask storage and transportation. Pre-storage drying-transfer operations and early stage storage subject cladding to higher temperatures and much higher pressure-induced tensile hoop stresses relative to in-reactor operation and pool storage. Under these conditions, radial hydrides may precipitate during slow cooling and provide an additional embrittlement mechanism as the cladding temperature decreases below the ductile-to-brittle transition temperature (DBTT). On the basis of previous test results, susceptibility to radial-hydride precipitation depends on cladding material, microstructure, and pre-drying distribution of hydrides across the cladding wall, as well as peak hoop stresses and temperatures during drying operations and storage. Susceptibility to embrittlement depends on the extent of radial-hydride precipitation and the thickness of the outer-surface hydride rim. These results highlight the importance of determining the DBTT for high-burnup cladding as a function of peak drying-storage temperatures and stresses and including the relevant mechanical properties in cask structural analyses. Additional testing is needed at lower (and perhaps more realistic) peak drying-storage temperatures and stresses, for which the DBTT is expected to decrease.

  11. A multi-platform linking code for fuel burnup and radiotoxicity analysis

    Science.gov (United States)

    Cunha, R.; Pereira, C.; Veloso, M. A. F.; Cardoso, F.; Costa, A. L.

    2014-02-01

    A linking code between ORIGEN2.1 and MCNP has been developed at the Departamento de Engenharia Nuclear/UFMG to calculate coupled neutronic/isotopic results for nuclear systems and to produce a large number of criticality, burnup and radiotoxicity results. In its previous version, it evaluated the isotopic composition evolution in a Heat Pipe Power System model as well as the radiotoxicity and radioactivity during lifetime cycles. In the new version, the code presents features such as multi-platform execution and automatic results analysis. Improvements made in the code allow it to perform simulations in a simpler and faster way without compromising accuracy. Initially, the code generates a new input for MCNP based on the decisions of the user. After that, MCNP is run and data, such as recoverable energy per prompt fission neutron, reaction rates and keff, are automatically extracted from the output and used to calculate neutron flux and cross sections. These data are then used to construct new ORIGEN inputs, one for each cell in the core. Each new input is run on ORIGEN and generates outputs that represent the complete isotopic composition of the core on that time step. The results show good agreement between GB (Coupled Neutronic/Isotopic code) and Monteburns (Automated, Multi-Step Monte Carlo Burnup Code System), developed by the Los Alamos National Laboratory.

  12. Data Mining Techniques to Estimate Plutonium, Initial Enrichment, Burnup, and Cooling Time in Spent Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Trellue, Holly Renee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fugate, Michael Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tobin, Stephen Joesph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-19

    The Next Generation Safeguards Initiative (NGSI), Office of Nonproliferation and Arms Control (NPAC), National Nuclear Security Administration (NNSA) of the U.S. Department of Energy (DOE) has sponsored a multi-laboratory, university, international partner collaboration to (1) detect replaced or missing pins from spent fuel assemblies (SFA) to confirm item integrity and deter diversion, (2) determine plutonium mass and related plutonium and uranium fissile mass parameters in SFAs, and (3) verify initial enrichment (IE), burnup (BU), and cooling time (CT) of facility declaration for SFAs. A wide variety of nondestructive assay (NDA) techniques were researched to achieve these goals [Veal, 2010 and Humphrey, 2012]. In addition, the project includes two related activities with facility-specific benefits: (1) determination of heat content and (2) determination of reactivity (multiplication). In this research, a subset of 11 integrated NDA techniques was researched using data mining solutions at Los Alamos National Laboratory (LANL) for their ability to achieve the above goals.

  13. Assessment of Fission Product Cross-Section Data for Burnup Credit Applications

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Luiz C [ORNL; Derrien, Herve [ORNL; Dunn, Michael E [ORNL; Mueller, Don [ORNL

    2007-12-01

    Past efforts by the Department of Energy (DOE), the Electric Power Research Institute (EPRI), the Nuclear Regulatory Commission (NRC), and others have provided sufficient technical information to enable the NRC to issue regulatory guidance for implementation of pressurized-water reactor (PWR) burnup credit; however, consideration of only the reactivity change due to the major actinides is recommended in the guidance. Moreover, DOE, NRC, and EPRI have noted the need for additional scientific and technical data to justify expanding PWR burnup credit to include fission product (FP) nuclides and enable burnup credit implementation for boiling-water reactor (BWR) spent nuclear fuel (SNF). The criticality safety assessment needed for burnup credit applications will utilize computational analyses of packages containing SNF with FP nuclides. Over the years, significant efforts have been devoted to the nuclear data evaluation of major isotopes pertinent to reactor applications (i.e., uranium, plutonium, etc.); however, efforts to evaluate FP cross-section data in the resonance region have been less thorough relative to actinide data. In particular, resonance region cross-section measurements with corresponding R-matrix resonance analyses have not been performed for FP nuclides. Therefore, the objective of this work is to assess the status and performance of existing FP cross-section and cross-section uncertainty data in the resonance region for use in burnup credit analyses. Recommendations for new cross-section measurements and/or evaluations are made based on the data assessment. The assessment focuses on seven primary FP isotopes (103Rh, 133Cs, 143Nd, 149Sm, 151Sm, 152Sm, and 155Gd) that impact reactivity analyses of transportation packages and two FP isotopes (153Eu and 155Eu) that impact prediction of 155Gd concentrations. Much of the assessment work was completed in 2005, and the assessment focused on the latest FP cross-section evaluations available in the

  14. Performance limitations for PWR fuel burnup extensions and high burnup complex loading patterns; Esquemas de recarga de combustible de alto quemado y limitaciones asociadas

    Energy Technology Data Exchange (ETDEWEB)

    Ahnert, C.; Aragones, J. M.; Cabellos, O.; Garcia Herranz, N. [Universidad Politecnica de Madrid (Spain)

    2000-07-01

    The analysis, design and on-line surveillance of pressurized water reactors require extensive and detailed 3D core calculations. The development and the improvement of codes are required due to the increasing heterogeneity in PWR (new type of fuel assemblies, complex loading patterns and safety and reliability requirements of nuclear reactor operation). The SEANAP system has been extensively validated and this system has been used to analyze high burnup fuel specifications and several types of long cycles. Some Programs (with Spanish participation) have been developed to study limitations for fuel burnup extensions: Robust Fuel Program, Segmented Rods Program and gain regulatory acceptance of fuel design and operation to higher burnup levels. (Author)

  15. Detailed description and user`s manual of high burnup fuel analysis code EXBURN-I

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Saitou, Hiroaki

    1997-11-01

    EXBURN-I has been developed for the analysis of LWR high burnup fuel behavior in normal operation and power transient conditions. In the high burnup region, phenomena occur which are different in quality from those expected for the extension of behaviors in the mid-burnup region. To analyze these phenomena, EXBURN-I has been formed by the incorporation of such new models as pellet thermal conductivity change, burnup-dependent FP gas release rate, and cladding oxide layer growth to the basic structure of low- and mid-burnup fuel analysis code FEMAXI-IV. The present report describes in detail the whole structure of the code, models, and materials properties. Also, it includes a detailed input manual and sample output, etc. (author). 55 refs.

  16. Impact of Reactor Operating Parameters on Cask Reactivity in BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ilas, Germina [ORNL; Betzler, Benjamin R [ORNL; Ade, Brian J [ORNL

    2017-01-01

    This paper discusses the effect of reactor operating parameters used in fuel depletion calculations on spent fuel cask reactivity, with relevance for boiling-water reactor (BWR) burnup credit (BUC) applications. Assessments that used generic BWR fuel assembly and spent fuel cask configurations are presented. The considered operating parameters, which were independently varied in the depletion simulations for the assembly, included fuel temperature, bypass water density, specific power, and operating history. Different operating history scenarios were considered for the assembly depletion to determine the effect of relative power distribution during the irradiation cycles, as well as the downtime between cycles. Depletion, decay, and criticality simulations were performed using computer codes and associated nuclear data within the SCALE code system. Results quantifying the dependence of cask reactivity on the assembly depletion parameters are presented herein.

  17. Mechanical Fatigue Testing of High-Burnup Fuel for Transportation Applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Wang, Hong [ORNL

    2015-05-01

    This report describes testing designed to determine the ability of high burnup (HBU) (>45 GWd/MTU) spent fuel to maintain its integrity under normal conditions of transportation. An innovative system, Cyclic Integrated Reversible-bending Fatigue Tester (CIRFT), has been developed at Oak Ridge National Laboratory (ORNL) to test and evaluate the mechanical behavior of spent nuclear fuel (SNF) under conditions relevant to storage and transportation. The CIRFT system is composed of a U-frame equipped with load cells for imposing the pure bending loads on the SNF rod test specimen and measuring the in-situ curvature of the fuel rod during bending using a set up with three linear variable differential transformers (LVDTs).

  18. Estimate of fuel burnup spatial a multipurpose reactor in computer simulation; Estimativa da queima espacial do combustivel de um reator multiproposito por simulacao computacional

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Nadia Rodrigues dos, E-mail: nadia.santos@ifrj.edu.br [Instituto Federal de Educacao, Ciencia e Tecnologia do Rio de Janeiro (IFRJ), Paracambi, RJ (Brazil); Lima, Zelmo Rodrigues de; Moreira, Maria de Lourdes, E-mail: malu@ien.gov.br, E-mail: zrlima@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    In previous research, which aimed, through computer simulation, estimate the spatial fuel burnup for the research reactor benchmark, material test research - International Atomic Energy Agency (MTR/IAEA), it was found that the use of the code in FORTRAN language, based on the diffusion theory of neutrons and WIMSD-5B, which makes cell calculation, bespoke be valid to estimate the spatial burnup other nuclear research reactors. That said, this paper aims to present the results of computer simulation to estimate the space fuel burnup of a typical multipurpose reactor, plate type and dispersion. the results were considered satisfactory, being in line with those presented in the literature. for future work is suggested simulations with other core configurations. are also suggested comparisons of WIMSD-5B results with programs often employed in burnup calculations and also test different methods of interpolation values obtained by FORTRAN. Another proposal is to estimate the burning fuel, taking into account the thermohydraulics parameters and the appearance of xenon. (author)

  19. Determination of uncertainties of PWR spent fuel radionuclide inventory based on real operational history data

    Energy Technology Data Exchange (ETDEWEB)

    Fast, Ivan; Bosbach, Dirk [Institute of Energy- and Climate Research, Nuclear Waste Management and Reactor Safety Research, IEK-6, Forschungszentrum, Julich GmbH, (Germany); Aksyutina, Yuliya; Tietze-Jaensch, Holger [German Product Control Office for Radioactive Waste (PKS), Institute of Energy- and Climate Research, Nuclear Waste Management and Reactor Safety Research, IEK-6, Forschungszentrum Julich GmbH, (Germany)

    2015-07-01

    A requisite for the official approval of the safe final disposal of SNF is a comprehensive specification and declaration of the nuclear inventory in SNF by the waste supplier. In the verification process both the values of the radionuclide (RN) activities and their uncertainties are required. Burn-up (BU) calculations based on typical and generic reactor operational parameters do not encompass any possible uncertainties observed in real reactor operations. At the same time, the details of the irradiation history are often not well known, which complicates the assessment of declared RN inventories. Here, we have compiled a set of burnup calculations accounting for the operational history of 339 published or anonymized real PWR fuel assemblies (FA). These histories were used as a basis for a 'SRP analysis', to provide information about the range of the values of the associated secondary reactor parameters (SRP's). Hence, we can calculate the realistic variation or spectrum of RN inventories. SCALE 6.1 has been employed for the burn-up calculations. The results have been validated using experimental data from the online database - SFCOMPO-1 and -2. (authors)

  20. Criticality Evaluation of GBC-32 Cask with HBN No.3 Fuels in PWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Do-Yeon; Yoon, Hyoungju; Park, Kwangheon; Hong, Ser Gi [Kyung Hee Univ., Yongin (Korea, Republic of)

    2015-10-15

    An application of burnup credit is able to increase the capacity in casks. In this paper, the criticality evaluation for burnup credit was performed for the GBC-32 cask with the fuel assemblies discharged after HBN No.3 Cycle 6 by SCALE6.1/STARBUCS and MCNP6 with the axial burnup distributions and average discharge burnups evaluated using DeCART and MASTER codes. The criticality evaluation for burnup credit was performed for the GBC-32 cask with the fuel assemblies discharged after HBN No.3 Cycle 6 by STARBUCS and MCNP6 codes with the axial burnup distributions and average discharge burnups evaluated using DeCART and MASTER codes. k{sub eff} values and end effects were calculated for 3 cooling times of 0, 20, and 30 years. From the results calculated in these conditions, the following conclusions are drawn. (1) 12 discharged fuel assemblies for the cooling time of 0 year were not allowed to be stored in the cask because the estimated k{sub eff} values exceeds 0.9146. (2) Most of the discharged fuel assemblies except for 3 discharged fuel assemblies were allowed to be stored for the cooling times of 20 and 30 years. (3) The end effects increased as the cooling time increases, within the maximums of 834.93 pcm for the cooling time of 0 year, 1684.45 pcm for 20 years, and 2178.92 pcm for 30 years.

  1. Simulation of triton burn-up in JET plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Loughlin, M.J.; Balet, B.; Jarvis, O.N.; Stubberfield, P.M. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-07-01

    This paper presents the first triton burn-up calculations for JET plasmas using the transport code TRANSP. Four hot ion H-mode deuterium plasmas are studied. For these discharges, the 2.5 MeV emission rises rapidly and then collapses abruptly. This phenomenon is not fully understood but in each case the collapse phase is associated with a large impurity influx known as the ``carbon bloom``. The peak 14 MeV emission occurs at this time, somewhat later than that of the 2.5 MeV neutron peak. The present results give a clear indication that there are no significant departures from classical slowing down and spatial diffusion for tritons in JET plasmas. (authors). 7 refs., 3 figs., 1 tab.

  2. Thermal behavior analysis of PWR fuel during RIA at various fuel burnups using modified theatre code

    Directory of Open Access Journals (Sweden)

    Nawaz Amjad

    2016-01-01

    Full Text Available The fuel irradiation and burnup causes geometrical and dimensional changes in the fuel rod which affects its thermal resistance and ultimately affects the fuel rod behavior during steady-state and transient conditions. The consistent analysis of fuel rod thermal performance is essential for precise evaluation of reactor safety in operational transients and accidents. In this work, analysis of PWR fuel rod thermal performance is carried out under steady-state and transient conditions at different fuel burnups. The analysis is performed by using thermal hydraulic code, THEATRe. The code is modified by adding burnup dependent fuel rod behavior models. The original code uses as-fabricated fuel rod dimensions during steady-state and transient conditions which can be modified to perform more consistent reactor safety analysis. AP1000 reactor is considered as a reference reactor for this analysis. The effect of burnup on steady-state fuel rod parameters has been investigated. For transient analysis, hypothetical reactivity initiated accident was simulated by considering a triangular power pulse of variable pulse height (relative to the full power reactor operating conditions and pulse width at different fuel burnups which corresponds to fresh fuel, low and medium burnup fuels. The effect of power pulse height, pulse width and fuel burnup on fuel rod temperatures has been investigated. The results of reactivity initiated accident analysis show that the fuel failure mechanisms are different for fresh fuel and fuel at different burnup levels. The fuel failure in fresh fuel is expected due to fuel melting as fuel temperature increases with increase in pulse energy (pulse height. However, at relatively higher burnups, the fuel failure is expected due to cladding failure caused by strong pellet clad mechanical interaction, where, the contact pressure increases beyond the cladding yield strength.

  3. Development of burnup dependent fuel rod model in COBRA-TF

    Science.gov (United States)

    Yilmaz, Mine Ozdemir

    The purpose of this research was to develop a burnup dependent fuel thermal conductivity model within Pennsylvania State University, Reactor Dynamics and Fuel Management Group (RDFMG) version of the subchannel thermal-hydraulics code COBRA-TF (CTF). The model takes into account first, the degradation of fuel thermal conductivity with high burnup; and second, the fuel thermal conductivity dependence on the Gadolinium content for both UO2 and MOX fuel rods. The modified Nuclear Fuel Industries (NFI) model for UO2 fuel rods and Duriez/Modified NFI Model for MOX fuel rods were incorporated into CTF and fuel centerline predictions were compared against Halden experimental test data and FRAPCON-3.4 predictions to validate the burnup dependent fuel thermal conductivity model in CTF. Experimental test cases from Halden reactor fuel rods for UO2 fuel rods at Beginning of Life (BOL), through lifetime without Gd2O3 and through lifetime with Gd 2O3 and a MOX fuel rod were simulated with CTF. Since test fuel rod and FRAPCON-3.4 results were based on single rod measurements, CTF was run for a single fuel rod surrounded with a single channel configuration. Input decks for CTF were developed for one fuel rod located at the center of a subchannel (rod-centered subchannel approach). Fuel centerline temperatures predicted by CTF were compared against the measurements from Halden experimental test data and the predictions from FRAPCON-3.4. After implementing the new fuel thermal conductivity model in CTF and validating the model with experimental data, CTF model was applied to steady state and transient calculations. 4x4 PWR fuel bundle configuration from Purdue MOX benchmark was used to apply the new model for steady state and transient calculations. First, one of each high burnup UO2 and MOX fuel rods from 4x4 matrix were selected to carry out single fuel rod calculations and fuel centerline temperatures predicted by CTF/TORT-TD were compared against CTF /TORT-TD /FRAPTRAN

  4. Burnup measurements on spent fuel elements of the RP-10 research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Vela Mora, Mariano; Gallardo Padilla, Alberto; Palomino, Jose Luis Castro, E-mail: mvela@ipen.gob.p [Instituto Peruano de Energia Nuclear (IPEN/Peru), Lima (Peru). Grupo de Calculo, Analisis y Seguridad de Reactores; Terremoto, Luis Antonio Albiac, E-mail: laaterre@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    This work describes the measurement, using nondestructive gamma-ray spectroscopy, of the average burnup attained by Material Testing Reactor (MTR) fuel elements irradiated in the RP-10 research reactor. Measurements were performed at the reactor storage pool area using {sup 137}Cs as the only burnup monitor, even for spent fuel elements with cooling times much shorter than two years. The experimental apparatus was previously calibrated in efficiency to obtain absolute average burnup values, which were compared against corresponding ones furnished by reactor physics calculations. The mean deviation between both values amounts to 6%. (author)

  5. Development of Technical Basis for Burnup Credit Regulatory Guidance in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Parks, Cecil V [ORNL; Wagner, John C [ORNL; Mueller, Don [ORNL; Gauld, Ian C [ORNL

    2011-01-01

    In the United States (U.S.) there has been and continues to be considerable interest in the increased use of burnup credit as part of the safety basis for SNF systems and this interest has motivated numerous technical studies related to the application of burnup credit for maintaining subcriticality. Responding to industry requests and needs, the U.S. Nuclear Regulatory Commission initiated a burnup credit research program, with support from the Oak Ridge National Laboratory, to develop regulatory guidance and the supporting technical basis for allowing and expanding the use of burnup credit in pressurized-water reactor SNF storage and transport applications. The objective of this paper is to summarize the work and significant accomplishments, with references to the technical reports and publications for complete details.

  6. Topical Report on Actinide-Only Burnup Credit for PWR Spent Nuclear Fuel Packages. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1998-09-01

    The objective of this topical report is to present to the NRC for review and acceptance a methodology for using burnup credit in the design of criticality control systems for PWR spent fuel transportation packages, while maintaining the criticality safety margins and related requirements of 10 CFR Part 71 and 72. The proposed methodology consists of five major steps as summarized below: (1) Validate a computer code system to calculate isotopic concentrations in SNF created during burnup in the reactor core and subsequent decay. (2) Validate a computer code system to predict the subcritical multiplication factor, keff, of a spent nuclear fuel package. (3) Establish bounding conditions for the isotopic concentration and criticality calculations. (4) Use the validated codes and bounding conditions to generate package loading criteria (burnup credit loading curves). and (5) Verify that SNF assemblies meet the package loading criteria and confirm proper fuel assembly selection prior to loading. (This step is required but the details are outside the scope of this topical report.) When reviewed and accepted by the NRC, this topical report will serve as a criterion document for criticality control analysts and will provide steps for the use of actinide-only burnup credit in the design of criticality control systems. The NRC-accepted burnup credit methodology will be used by commercial SNF storage and transportation package designers. Design-specific burnup credit criticality analyses will be defined, developed, and documented in the Safety Analysis Report (SAR) for each specific storage or transportation package that uses burnup credit. These SARs will then be submitted to the NRC for review and approval. This topical report is expected to be referenced in a number of storage and transportation cask applications to be submitted by commercial cask and canister designers to the NRC. Therefore, NRC acceptance of this topical report will result in increased efficiency of the

  7. Development of Monteburns: A Code That Links MCNP and ORIGEN2 in an Automated Fashion for Burnup Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Holly R. Trellue

    1998-12-01

    Monteburns is a fully automated tool that links the Monte Carlo transport code MCNP with the radioactive decay and burnup code 0RIGEN2. Monteburns produces many criticality and burnup computational parameters based on material feed/removal specifications, power(s), and time intervals. This code processes input from the user indicating the system geometry, initial material compositions, feed/removal, and other code-specific parameters. Results from MCNP, 0RIGEN2, and other calculations are then output successively as the code runs. The principle function of monteburns is to first transfer one-group cross sections and fluxes from MCNP to 0RIGEN2, and then transfer the resulting material compositions (after irradiation and/or decay) from 0RIGEN2 back to MCNP in a repeated, cyclic fashion. The main requirement of the code is that the user have a working MCNP input file and other input parameters; all interaction with 0RIGEN2 and other calculations are performed by monteburns. This report presents the results obtained from the benchmarking of monteburns to measured and previously obtained data from traditional Light Water Reactor systems. The majority of the differences seen between the two were less than five percent. These were primarily a result of variances in cross sections between MCNP, cross section libraries used by other codes, and observed values. With this understanding, this code can now be used with confidence for burnup calculations in three-dimensional systems. It was designed for use in the Accelerator Transmutation of Waste project at Los Alamos National Laboratory but is also being applied to the analysis of isotopic production/destruction of transuranic actinides in a reactor system. The code has now been shown to sufficiently support these calculations.

  8. French investigations of high burnup effect on LOCA thermomecanical behavior. Part two. Oxidation and quenching experiments under simulated LOCA conditions with high burnup clad material

    Energy Technology Data Exchange (ETDEWEB)

    GrandJean, C. [IPSN, Cadarache (France); Cauvin, R.; Lebuffe, C. [EDF/SCMI, Chinon (France)] [and others

    1997-01-01

    In the frame of the high burnup fuel studies to support a possible extension of the current discharge burnup limit, experimental programs have been undertaken, jointly by EDF and IPSN in order to study the thermal-shock behavior of high burnup fuel claddings under typical LOCA conditions. The TAGUS program used unirradiated cladding samples, bare or bearing a pre-corrosion state simulating the end-of-life state of high burnup fuel claddings: the TAGCIR program used actually irradiated cladding samples taken from high burnup rods irradiated over 5 cycles in a commercial EDF PWR and having reached a rod burnup close to 60 GWd/tU. The thermal-shock failure tests consisted in oxidizing the cladding samples under steam flow, on both inner and outer faces or on the outer face alone, and subjecting them to a final water quench. The heating was provided by an inductive furnace the power of which being regulated through monitoring of the sample surface temperature with use of a single-wave optical pyrometer. Analysis of the irradiated tests (TAGCIR series) evidenced an increased oxidation rate as compared to similar tests on unirradiated samples. Results of the quenching tests series on unirradiated and irradiated samples are plotted under the usual presentation of failure maps relative to the oxidation parameters ECR (equivalent cladding reacted) or e{sub {beta}} (thickness of the remaining beta phase layer) as a function of the oxidation temperature. Comparison of the failure limits for irradiated specimens to those for unirradiated specimens indicates a lower brittleness under two side oxidation and possibly the opposite under one-side oxidation. The tentative analysis of the oxidation and quenching tests results on irradiated samples reveals the important role played by the hydrogen charged during in-reactor corrosion on the oxidation kinetics and the failure bearing capability of the cladding under LOCA transient conditions.

  9. Benchmark calculation of SCALE-PC 4.3 CSAS6 module and burnup credit criticality analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hee Sung; Ro, Seong Gy; Shin, Young Joon; Kim, Ik Soo [Korea Atomic Energy Research Institute, Taejon (Korea)

    1998-12-01

    Calculation biases of SCALE-PC CSAS6 module for PWR spent fuel, metallized spent fuel and solution of nuclear materials have been determined on the basis of the benchmark to be 0.01100, 0.02650 and 0.00997, respectively. With the aid of the code system, nuclear criticality safety analysis for the spent fuel storage pool has been carried out to determine the minimum burnup of spent fuel required for safe storage. The criticality safety analysis is performed using three types of isotopic composition of spent fuel: ORIGEN2-calculated isotopic compositions; the conservative inventory obtained from the multiplication of ORIGEN2-calculated isotopic compositions by isotopic correction factors; the conservative inventory of only U, Pu and {sup 241}Am. The results show that the minimum burnup for three cases are 990,6190 and 7270 MWd/tU, respectively in the case of 5.0 wt% initial enriched spent fuel. (author). 74 refs., 68 figs., 35 tabs.

  10. A Criticality Evaluation of the GBC-32 Dry Storage Cask in PWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hyoungju; Park, Kwangheon; Hong, Ser Gi [Kyung Hee Univ., Yongin (Korea, Republic of)

    2015-05-15

    The current criticality safety evaluation assumes the only unirradiated fresh fuels with the maximum enrichment in a dry storage cask (DSC) for conservatism without consideration of the depletion of fissile nuclides and the generation of neutron-absorbing fission products. However, the large conservatism leads to the significant increase of the storage casks required. Thus, the application of burnup credit which takes credit for the reduction of reactivity resulted from fuel depletion can increase the capacity in storage casks. On the other hand, the burnup credit application introduces lots of complexity into a criticality safety analysis such as the accurate estimation of the isotopic inventories and the burnup of UNFs and the validation of the criticality calculation. The criticality evaluation with an effect of burnup credit was performed for the DSC of GBC-32 by using SCALE 6.1/STARBUCS. keff values were calculated as a function of burnup and cooling time for four initial enrichments of 2, 3, 4, and 5 wt. % 235U. The values were calculated for the burnup range of 0 to 60,000 MWD/MTU, in increments of 10,000 MWD/MTU, and for five cooling times of 0, 5, 10, 20, and 40 years.

  11. High Burn-Up Spent Nuclear Fuel Vibration Integrity Study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiang, Hao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce Balkcom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Rob L [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Scaglione, John M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    The Oak Ridge National Laboratory (ORNL) has developed the cyclic integrated reversible-bending fatigue tester (CIRFT) approach to successfully demonstrate the controllable fatigue fracture on high burnup (HBU) spent nuclear fuel (SNF) in a normal vibration mode. CIRFT enables examination of the underlying mechanisms of SNF system dynamic performance. Due to the inhomogeneous composite structure of the SNF system, the detailed mechanisms of the pellet-pellet and pellet-clad interactions and the stress concentration effects at the pellet-pellet interface cannot be readily obtained from a CIRFT system measurement. Therefore, finite element analyses (FEAs) are used to translate the global moment-curvature measurement into local stress-strain profiles for further investigation. The major findings of CIRFT on the HBU SNF are as follows: SNF system interface bonding plays an important role in SNF vibration performance. Fuel structure contributes to SNF system stiffness. There are significant variations in stress and curvature of SNF systems during vibration cycles resulting from segment pellets and clad interactions. SNF failure initiates at the pellet-pellet interface region and appears to be spontaneous.

  12. Topical report on actinide-only burnup credit for PWR spent nuclear fuel packages. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1997-04-01

    A methodology for performing and applying nuclear criticality safety calculations, for PWR spent nuclear fuel (SNF) packages with actinide-only burnup credit, is described. The changes in the U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, and Am-241 concentration with burnup are used in burnup credit criticality analyses. No credit for fission product neutron absorbers is taken. The methodology consists of five major steps. (1) Validate a computer code system to calculate isotopic concentrations of SNF created during burnup in the reactor core and subsequent decay. A set of chemical assay benchmarks is presented for this purpose as well as a method for assessing the calculational bias and uncertainty, and conservative correction factors for each isotope. (2) Validate a computer code system to predict the subcritical multiplication factor, k{sub eff}, of a spent nuclear fuel package. Fifty-seven UO{sub 2}, UO{sub 2}/Gd{sub 2}O{sub 3}, and UO{sub 2}/PuO{sub 2} critical experiments have been selected to cover anticipated conditions of SNF. The method uses an upper safety limit on k{sub eff} (which can be a function of the trending parameters) such that the biased k{sub eff}, when increased for the uncertainty is less than 0.95. (3) Establish bounding conditions for the isotopic concentration and criticality calculations. Three bounding axial profiles have been established to assure the ''end effect'' is accounted for conservatively. (4) Use the validated codes and bounding conditions to generate package loading criteria (burnup credit loading curves). Burnup credit loading curves show the minimum burnup required for a given initial enrichment. The utility burnup record is compared to this requirement after the utility accounts for the uncertainty in its record. Separate curves may be generated for each assembly design, various minimum cooling times and burnable absorber histories. (5) Verify that SNF assemblies meet the package

  13. Summary of high burnup fuel issues and NRC`s plan of action

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, R.O.

    1997-01-01

    For the past two years the Office of Nuclear Regulatory Research has concentrated mostly on the so-called reactivity-initiated accidents -- the RIAs -- in this session of the Water Reactor Safety Information Meeting, but this year there is a more varied agenda. RIAs are, of course, not the only events of interest for reactor safety that are affected by extended burnup operation. Their has now been enough time to consider a range of technical issues that arise at high burnup, and a list of such issues being addressed in their research program is given here. (1) High burnup capability of the steady-state code (FRAPCON) used for licensing audit calculations. (2) General capability (including high burnup) of the transient code (FRAPTRAN) used for special studies. (3) Adequacy at high burnup of fuel damage criteria used in regulation for reactivity accidents. (4) Adequacy at high burnup of models and fuel related criteria used in regulation for loss-of-coolant accidents (LOCAs). (5) Effect of high burnup on fuel system damage during normal operation, including control rod insertion problems. A distinction is made between technical issues, which may or may not have direct licensing impacts, and licensing issues. The RIAs became a licensing issue when the French test in CABRI showed that cladding failures could occur at fuel enthalpies much lower than a value currently used in licensing. Fuel assembly distortion became a licensing issue when control rod insertion was affected in some operating plants. In this presentation, these technical issues will be described and the NRC`s plan of action to address them will be discussed.

  14. Development of external coupling for calculation of the control rod worth in terms of burn-up for a WWER-1000 nuclear reactor

    Energy Technology Data Exchange (ETDEWEB)

    Noori-Kalkhoran, Omid, E-mail: o_noori@yahoo.com [Reactor Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Yarizadeh-Beneh, Mehdi [Faculty of Engineering, Shahid Beheshti University, Tehran (Iran, Islamic Republic of); Ahangari, Rohollah [Reactor Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of)

    2016-08-15

    Highlights: • Calculation of control rod worth in term of burn-up. • Calculation of differential and integral control rod worth. • Developing an external couple. • Modification of thermal-hydraulic profiles in calculations. - Abstract: One of the main problems relating to operation of a nuclear reactor is its safety and controlling system. The most widely used control systems for thermal reactors are neutron absorbent rods. In this study a code based method has been developed for calculation of integral and differential control rod worth in terms of burn-up for a WWER-1000 nuclear reactor. External coupling of WIMSD-5B, PARCS V2.7 and COBRA-EN has been used for this purpose. WIMSD-5B has been used for cell calculation and handling burn-up of the core in various days. PARCS V2.7 has been used for neutronic calculation of core and critical boron concentration search. Thermal-hydraulic calculation has been performed by COBRA-EN. An external coupling algorithm has been developed by MATLAB to couple and transfer suitable data between these codes in each step. Steady-State Power Picking Factors (PPFs) of the core and control rod worth for different control rod groups have been calculated from Beginning Of Cycle (BOC) to 289.7 Effective Full Power Days (EFPDs) in some steps. Results have been compared with the results of Bushehr Nuclear Power Plant (BNPP) Final Safety Analysis Report (FSAR). The results show a good agreement and confirm the ability of developed coupling in calculation of control rod worth in terms of burn-up.

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

    Science.gov (United States)

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

    2012-01-01

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

  16. Development of a parallel processing couple for calculations of control rod worth in terms of burn-up in a WWER-1000 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Noori-Kalkhoran, Omid; Ahangari, R. [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of). Reactor Research school; Shirani, A.S. [Shahid Beheshti Univ., Tehran (Iran, Islamic Republic of). Faculty of Engineering

    2017-03-15

    In this study a code based method has been developed for calculation of integral and differential control rod worth in terms of burn-up for a WWER-1000 reactor. Parallel processing of WIMSD-5B, PARCS V2.7 and COBRA-EN has been used for this purpose. WIMSD-5B has been used for cell calculation and handling burn-up of core at different days. PARCS V2.7?has been used for neutronic calculation of core and critical boron concentration search. Thermal-hydraulic calculation has been performed by COBRA-EN. A Parallel processing algorithm has been developed by MATLAB to couple and transfer suitable data between these codes in each step. Steady-State Power Picking Factors (PPFs) of the core and Control rod worth have been calculated from Beginning Of Cycle (BOC) to 289.7 Effective full Power Days (EFPDs) in some steps. Results have been compared with Bushehr Nuclear Power Plant (BNPP) Final Safety Analysis Report (FSAR) results. The results show great similarity and confirm the ability of developed coupling in calculation of control rod worth in terms of burn-up.

  17. Propagation of Nuclear Data Uncertainties for ELECTRA Burn-up Calculations

    Science.gov (United States)

    Sjöstrand, H.; Alhassan, E.; Duan, J.; Gustavsson, C.; Koning, A. J.; Pomp, S.; Rochman, D.; Österlund, M.

    2014-04-01

    The European Lead-Cooled Training Reactor (ELECTRA) has been proposed as a training reactor for fast systems within the Swedish nuclear program. It is a low-power fast reactor cooled by pure liquid lead. In this work, we propagate the uncertainties in 239Pu transport data to uncertainties in the fuel inventory of ELECTRA during the reactor lifetime using the Total Monte Carlo approach (TMC). Within the TENDL project, nuclear models input parameters were randomized within their uncertainties and 740 239Pu nuclear data libraries were generated. These libraries are used as inputs to reactor codes, in our case SERPENT, to perform uncertainty analysis of nuclear reactor inventory during burn-up. The uncertainty in the inventory determines uncertainties in: the long-term radio-toxicity, the decay heat, the evolution of reactivity parameters, gas pressure and volatile fission product content. In this work, a methodology called fast TMC is utilized, which reduces the overall calculation time. The uncertainty of some minor actinides were observed to be rather large and therefore their impact on multiple recycling should be investigated further. It was also found that, criticality benchmarks can be used to reduce inventory uncertainties due to nuclear data. Further studies are needed to include fission yield uncertainties, more isotopes, and a larger set of benchmarks.

  18. Effects of microstructural constraints on the transport of fission products in uranium dioxide at low burnups

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Harn Chyi; Rudman, Karin; Krishnan, Kapil; McDonald, Robert [Arizona State University, Tempe, AZ (United States); Dickerson, Patricia [Los Alamos National Lab, Los Alamos, NM (United States); Gong, Bowen [Arizona State University, Tempe, AZ (United States); Peralta, Pedro, E-mail: pperalta@asu.edu [Arizona State University, Tempe, AZ (United States)

    2016-08-15

    Diffusion of fission gases in UO{sub 2} is studied at low burnups, before bubble growth and coalescence along grain boundaries (GBs) become dominant, using a 3-D finite element model that incorporates actual UO{sub 2} microstructures. Grain boundary diffusivities are assigned based on crystallography with lattice and GB diffusion coupled with temperature to account for temperature gradients. Heterogeneity of GB properties and connectivity can induce regions where concentration is locally higher than without GB diffusion. These regions are produced by “bottlenecks” in the GB network because of lack of connectivity among high diffusivity GBs due to crystallographic constraints, and they can lead to localized swelling. Effective diffusivities were calculated assuming a uniform distribution of high diffusivity among GBs. Results indicate an increase over the bulk diffusivity with a clear grain size effect and that connectivity and properties of different GBs become important factors on the variability of fission product concentration at the microscale. - Highlights: • Microstructure models are developed to study fission gas transport in oxide fuels. • Crystallographic and temperature dependent material properties are applied. • Fission product concentration is affected by grain boundary distribution. • High concentration regions can form as controlled by the grain boundary connectivity.

  19. EPRI/DOE High-Burnup Fuel Sister Rod Test Plan Simplification and Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Saltzstein, Sylvia J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorenson, Ken B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hanson, B. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shimskey, R. W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Klymyshyn, N. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Webster, R. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jensen, P. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); MacFarlan, P. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billone, Mike [Argonne National Lab. (ANL), Argonne, IL (United States); Scaglione, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-15

    The EPRI/DOE High-Burnup Confirmatory Data Project (herein called the “Demo”) is a multi-year, multi-entity test with the purpose of providing quantitative and qualitative data to show if high-burnup fuel mechanical properties change in dry storage over a ten-year period. The Demo involves obtaining 32 assemblies of high-burnup PWR fuel of common cladding alloys from the North Anna Nuclear Power Plant, loading them in an NRC-licensed TN-32B cask, drying them according to standard plant procedures, and then storing them on the North Anna dry storage pad for ten years. After the ten-year storage time, the cask will be opened and the mechanical properties of the rods will be tested and analyzed.

  20. An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses--Criticality (keff) Predictions

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, John M [ORNL; Mueller, Don [ORNL; Wagner, John C [ORNL

    2011-01-01

    One of the most significant remaining challenges associated with expanded implementation of burnup credit in the United States is the validation of depletion and criticality calculations used in the safety evaluation - in particular, the availability and use of applicable measured data to support validation, especially for fission products. Applicants and regulatory reviewers have been constrained by both a scarcity of data and a lack of clear technical basis or approach for use of the data. U.S. Nuclear Regulatory Commission (NRC) staff have noted that the rationale for restricting their Interim Staff Guidance on burnup credit (ISG-8) to actinide-only is based largely on the lack of clear, definitive experiments that can be used to estimate the bias and uncertainty for computational analyses associated with using burnup credit. To address the issue of validation, the NRC initiated a project with the Oak Ridge National Laboratory to (1) develop and establish a technically sound validation approach (both depletion and criticality) for commercial spent nuclear fuel (SNF) criticality safety evaluations based on best-available data and methods and (2) apply the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The purpose of this paper is to describe the criticality (k{sub eff}) validation approach, and resulting observations and recommendations. Validation of the isotopic composition (depletion) calculations is addressed in a companion paper at this conference. For criticality validation, the approach is to utilize (1) available laboratory critical experiment (LCE) data from the International Handbook of Evaluated Criticality Safety Benchmark Experiments and the French Haut Taux de Combustion (HTC) program to support validation of the principal actinides and (2) calculated sensitivities, nuclear data uncertainties, and the limited available fission

  1. Impact investigation of reactor fuel operating parameters on reactivity for use in burnup credit applications

    Science.gov (United States)

    Sloma, Tanya Noel

    When representing the behavior of commercial spent nuclear fuel (SNF), credit is sought for the reduced reactivity associated with the net depletion of fissile isotopes and the creation of neutron-absorbing isotopes, a process that begins when a commercial nuclear reactor is first operated at power. Burnup credit accounts for the reduced reactivity potential of a fuel assembly and varies with the fuel burnup, cooling time, and the initial enrichment of fissile material in the fuel. With regard to long-term SNF disposal and transportation, tremendous benefits, such as increased capacity, flexibility of design and system operations, and reduced overall costs, provide an incentive to seek burnup credit for criticality safety evaluations. The Nuclear Regulatory Commission issued Interim Staff Guidance 8, Revision 2 in 2002, endorsing burnup credit of actinide composition changes only; credit due to actinides encompasses approximately 30% of exiting pressurized water reactor SNF inventory and could potentially be increased to 90% if fission product credit were accepted. However, one significant issue for utilizing full burnup credit, compensating for actinide and fission product composition changes, is establishing a set of depletion parameters that produce an adequately conservative representation of the fuel's isotopic inventory. Depletion parameters can have a significant effect on the isotopic inventory of the fuel, and thus the residual reactivity. This research seeks to quantify the reactivity impact on a system from dominant depletion parameters (i.e., fuel temperature, moderator density, burnable poison rod, burnable poison rod history, and soluble boron concentration). Bounding depletion parameters were developed by statistical evaluation of a database containing reactor operating histories. The database was generated from summary reports of commercial reactor criticality data. Through depletion calculations, utilizing the SCALE 6 code package, several light

  2. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  3. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason M.; Demkowicz, Paul A.; Stempien, John D.

    2016-11-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  4. NUCLEAR DATA UNCERTAINTY PROPAGATION FOR A TYPICAL PWR FUEL ASSEMBLY WITH BURNUP

    Directory of Open Access Journals (Sweden)

    D. ROCHMAN

    2014-06-01

    Full Text Available The effects of nuclear data uncertainties are studied on a typical PWR fuel assembly model in the framework of the OECD Nuclear Energy Agency UAM (Uncertainty Analysis in Modeling expert working group. The “Fast Total Monte Carlo” method is applied on a model for the Monte Carlo transport and burnup code SERPENT. Uncertainties on k∞, reaction rates, two-group cross sections, inventory and local pin power density during burnup are obtained, due to transport cross sections for the actinides and fission products, fission yields and thermal scattering data.

  5. Fuel burnup calculation of Ghana MNSR using ORIGEN2 and REBUS3 codes.

    Science.gov (United States)

    Abrefah, R G; Nyarko, B J B; Fletcher, J J; Akaho, E H K

    2013-10-01

    Ghana Research Reactor-1 core is to be converted from HEU fuel to LEU fuel in the near future and managing the spent nuclear fuel is very important. A fuel depletion analysis of the GHARR-1 core was performed using ORIGEN2 and REBUS3 codes to estimate the isotopic inventory at end-of-cycle in order to help in the design of an appropriate spent fuel cask. The results obtained for both codes were consistent for U-235 burnup weight percent and Pu-239 build up as a result of burnup. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Nuclear Energy Research Initiative. Development of a Stabilized Light Water Reactor Fuel Matrix for Extended Burnup

    Energy Technology Data Exchange (ETDEWEB)

    BD Hanson; J Abrefah; SC Marschman; SG Prussin

    2000-09-08

    The main objective of this project is to develop an advanced fuel matrix capable of achieving extended burnup while improving safety margins and reliability for present operations. In the course of this project, the authors improve understanding of the mechanism for high burnup structure (HBS) formation and attempt to design a fuel to minimize its formation. The use of soluble dopants in the UO{sub 2} matrix to stabilize the matrix and minimize fuel-side corrosion of the cladding is the main focus.

  7. Progress of the RIA experiments with high burnup fuels and their evaluation in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Ishijima, Kiyomi; Fuketa, Toyoshi [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)

    1997-01-01

    Recent results obtained in the NSRR power burst experiments with high burnup PWR fuel rods are described and discussed in this paper. Data concerning test condition, transient records during pulse irradiation and post irradiation examination are described. Another high burnup PWR fuel rod failed in the test HBO-5 at the slightly higher energy deposition than that in the test HBO-1. The failure mechanism of the test HBO-5 is the same as that of the test HBO-1, that is, hydride-assisted PCMI. Some influence of the thermocouples welding on the failure behavior of the HBO-5 rod was observed.

  8. Post Irradiation Examination Plan for High-Burnup Demonstration Project Sister Rods

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, John M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce Balkcom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    This test plan describes the experimental work to be implemented by the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) to characterize high burnup (HBU) spent nuclear fuel (SNF) in conjunction with the High Burnup Dry Storage Cask Research and Development Project and serves to coordinate and integrate the multi-year experimental program to collect and develop data regarding the continued storage and eventual transport of HBU (i.e., >45 GWd/MTU) SNF. The work scope involves the development, performance, technical integration, and oversight of measurements and collection of relevant data, guided by analyses and demonstration of need.

  9. Analysis of Corrosion Residues Collected from the Aluminum Basket Rails of the High-Burnup Demonstration Cask.

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-03-01

    On September, 2015, an inspection was performed on the TN-32B cask that will be used for the high-burnup demonstration project. During the survey, wooden cribbing that had been placed within the cask eleven years earlier to prevent shifting of the basket during transport was removed, revealing two areas of residue on the aluminum basket rails, where they had contacted the cribbing. The residue appeared to be a corrosion product, and concerns were raised that similar attack could exist at more difficult-to-inspect locations in the canister. Accordingly, when the canister was reopened, samples of the residue were collected for analysis. This report presents the results of that assessment, which determined that the corrosion was due to the presence of the cribbing. The corrosion was associated with fungal material, and fungal activity likely contributed to an aggressive chemical environment. Once the cask has been cleaned, there will be no risk of further corrosion.

  10. French investigations of high burnup effect on LOCA thermomechanical behavior: Part 1. Experimental programmes in support of LOCA design methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Waeckel, N. [EDF/SEPTEN Villeurbanne (France); GrandJean, C. [IPSN, Cadarache (France); Cauvin, R.; Lebuffe, C. [EDF/SCMI, Chinon (France)

    1997-01-01

    Within the framework of Burn-Up extension request, EDF, FRAMATOME, CEA and IPSN have carried out experimental programmes in order to provide the design of fuel rods under LOCA conditions with relevant data. The design methods used in France for LOCA are based on standard Appendix K methodology updated to take into account some penalties related to the actual conditions of the Nuclear Power Plant. Best-Estimate assessments are used as well. Experimental programmes concern plastic deformation and burst behavior of advanced claddings (EDGAR) and thermal shock quenching behavior of highly irradiated claddings (TAGCIR). The former reveals the important role played by the {alpha}/{beta} transformation kinetics related to advanced alloys (Niobium alloys) and the latter the significative impact of hydrogen charged during in-reactor corrosion on oxidation kinetics and failure behavior in terms of cooling rates.

  11. The Gd-isotopic fuel for high burnup in PWR's

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Marcio Soares; Mattos, João Roberto L. de; Andrade, Edison Pereira de, E-mail: marciod@cdtn.br, E-mail: jrmattos@cdtn.br, E-mail: epa@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Today, the discussion about the high burnup fuel is beyond the current fuel enrichment licensing and burnup limits. Licensing issues and material/design developments are again key features in further development of the LWR fuel design. Nevertheless, technological and economical solutions are already available or will be available in a short time. In order to prevent the growth of the technological gap, Brazil's nuclear sector needs to invest in the training of new human resources, in the access to international databases, and in the upgrading existing infrastructure. Experimental database and R&D infrastructure are essential components to support the autonomous development of Brazilian Nuclear Reactors, promoting the development of national technologies. The (U,Gd)O{sub 2} isotopic fuel proposed by the CDTN's staff solve two main issues in the high burnup fuel, which are (1) the peak of reactivity resulting from the Gd-157 fast burnup, and (2) the peak of temperature in the (U,Gd)O{sub 2} nuclear fuel resulting from detrimental effects in the thermal properties for gadolinia additions higher than 2%. A sustainable future can be envisaged for the nuclear energy. (author)

  12. About a fuel for burnup reactor of periodical pulsed nuclear pumped laser

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, A.I.; Lukin, A.V.; Magda, L.E.; Magda, E.P.; Pogrebov, I.S.; Putnikov, I.S.; Khmelnitsky, D.V.; Scherbakov, A.P. [Russian Federal Nuclear Center, Snezhinsk (Russian Federation)

    1998-07-01

    A physical scheme of burnup reactor for a Periodic Pulsed Nuclear Pumped Laser was supposed. Calculations of its neutron physical parameters were made. The general layout and construction of basic elements of the reactor are discussed. The requirements for the fuel and fuel elements are established. (author)

  13. Dependence of heavy metal burnup on nuclear data libraries for fast reactors

    CERN Document Server

    Ohki, S

    2003-01-01

    Japan Nuclear Cycle Development Institute (JNC) is considering the highly burnt fuel as well as the recycling of minor actinide (MA) in the development of commercialized fast reactor cycle systems. Higher accuracy in burnup calculation is going to be required for higher mass plutonium isotopes ( sup 2 sup 4 sup 0 Pu, etc.) and MA nuclides. In the framework of research and development aiming at the validation and necessary improvements of fast reactor burnup calculation, we investigated the differences among the burnup calculation results with the major nuclear data libraries: JEF-2.2, ENDF/B-VI Release 5, JENDL-3.2, and JENDL-3.3. We focused on the heavy metal nuclides such as plutonium and MA in the central core region of a conventional sodium-cooled fast reactor. For main heavy metal nuclides ( sup 2 sup 3 sup 5 U, sup 2 sup 3 sup 8 U, sup 2 sup 3 sup 9 Pu, sup 2 sup 4 sup 0 Pu, and sup 2 sup 4 sup 1 Pu), number densities after 1-cycle burnup did not change over one or two percent. Library dependence was re...

  14. Depletion of gadolinium burnable poison in a PWR assembly with high burnup fuel

    Energy Technology Data Exchange (ETDEWEB)

    Refeat, Riham Mahmoud [Nuclear and Radiological Regulatory Authority (NRRA), Cairo (Egypt). Safety Engineering Dept.

    2015-12-15

    A tendency to increase the discharge burnup of nuclear fuel for Advanced Pressurized Water Reactors (PWR) has been a characteristic of its operation for many years. It will be able to burn at very high burnup of about 70 GWd/t with UO{sub 2} fuels. The U-235 enrichment must be higher than 5 %, which leads to the necessity of using an extremely efficient burnable poison like Gadolinium oxide. Using gadolinium isotope is significant due to its particular depletion behavior (''Onion-Skin'' effect). In this paper, the MCNPX2.7 code is used to calculate the important neutronic parameters of the next generation fuels of PWR. K-infinity, local peaking factor and fission rate distributions are calculated for a PWR assembly which burn at very high burnup reaching 70 GWd/t. The calculations are performed using the recently released evaluated Gadolinium cross section data. The results obtained are close to those of a LWR next generation fuel benchmark problem. This demonstrates that the calculation scheme used is able to accurately model a PWR assembly that operates at high burnup values.

  15. A complete NUHOMS {sup registered} solution for storage and transport of high burnup spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bondre, J. [Transnuclear, Inc. (AREVA Group), Fremont, CA (United States)

    2004-07-01

    The discharge burnups of spent fuel from nuclear power plants keep increasing with plants discharging or planning to discharge fuel with burnups in excess of 60,000 MWD/MTU. Due to limited capacity of spent fuel pools, transfer of older cooler spent fuel from fuel pool to dry storage, and very limited options for transport of spent fuel, there is a critical need for dry storage of high burnup, higher heat load spent fuel so that plants could maintain their full core offload reserve capability. A typical NUHOMS {sup registered} solution for dry spent fuel storage is shown in the Figure 1. Transnuclear, Inc. offers two advanced NUHOMS {sup registered} solutions for the storage and transportation of high burnup fuel. One includes the NUHOMS {sup registered} 24PTH system for plants with 90.7 Metric Ton (MT) crane capacity; the other offers the higher capacity NUHOMS {sup registered} 32PTH system for higher crane capacity. These systems include NUHOMS {sup registered} - 24PTH and -32PTH Transportable Canisters stored in a concrete storage overpack (HSM-H). These canisters are designed to meet all the requirements of both storage and transport regulations. They are designed to be transported off-site either directly from the spent fuel pool or from the storage overpack in a suitable transport cask.

  16. Estimating NIRR-1 burn-up and core life time expectancy using the codes WIMS and CITATION

    Science.gov (United States)

    Yahaya, B.; Ahmed, Y. A.; Balogun, G. I.; Agbo, S. A.

    The Nigeria Research Reactor-1 (NIRR-1) is a low power miniature neutron source reactor (MNSR) located at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria Nigeria. The reactor went critical with initial core excess reactivity of 3.77 mk. The NIRR-1 cold excess reactivity measured at the time of commissioning was determined to be 4.97 mk, which is more than the licensed range of 3.5-4 mk. Hence some cadmium poison worth -1.2 mk was inserted into one of the inner irradiation sites which act as reactivity regulating device in order to reduce the core excess reactivity to 3.77 mk, which is within recommended licensed range of 3.5 mk and 4.0 mk. In this present study, the burn-up calculations of the NIRR-1 fuel and the estimation of the core life time expectancy after 10 years (the reactor core expected cycle) have been conducted using the codes WIMS and CITATION. The burn-up analyses carried out indicated that the excess reactivity of NIRR-1 follows a linear decreasing trend having 216 Effective Full Power Days (EFPD) operations. The reactivity worth of top beryllium shim data plates was calculated to be 19.072 mk. The result of depletion analysis for NIRR-1 core shows that (7.9947 ± 0.0008) g of U-235 was consumed for the period of 12 years of operating time. The production of the build-up of Pu-239 was found to be (0.0347 ± 0.0043) g. The core life time estimated in this research was found to be 30.33 years. This is in good agreement with the literature

  17. High Burnup Dry Storage Cask Research and Development Project, Final Test Plan

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-02-27

    EPRI is leading a project team to develop and implement the first five years of a Test Plan to collect data from a SNF dry storage system containing high burnup fuel.12 The Test Plan defined in this document outlines the data to be collected, and the storage system design, procedures, and licensing necessary to implement the Test Plan.13 The main goals of the proposed test are to provide confirmatory data14 for models, future SNF dry storage cask design, and to support license renewals and new licenses for ISFSIs. To provide data that is most relevant to high burnup fuel in dry storage, the design of the test storage system must mimic real conditions that high burnup SNF experiences during all stages of dry storage: loading, cask drying, inert gas backfilling, and transfer to the ISFSI for multi-year storage.15 Along with other optional modeling, SETs, and SSTs, the data collected in this Test Plan can be used to evaluate the integrity of dry storage systems and the high burnup fuel contained therein over many decades. It should be noted that the Test Plan described in this document discusses essential activities that go beyond the first five years of Test Plan implementation.16 The first five years of the Test Plan include activities up through loading the cask, initiating the data collection, and beginning the long-term storage period at the ISFSI. The Test Plan encompasses the overall project that includes activities that may not be completed until 15 or more years from now, including continued data collection, shipment of the Research Project Cask to a Fuel Examination Facility, opening the cask at the Fuel Examination Facility, and examining the high burnup fuel after the initial storage period.

  18. Group Constants Generation of the Pseudo Fission Products for Fast Reactor Burnup Calculations

    Science.gov (United States)

    Gil, Choong-Sup; Kim, Do Heon; Chang, Jonghwa

    2005-05-01

    The pseudo fission products for the burnup calculations of the liquid metal fast reactor were generated. The cross-section data and fission product yield data of ENDF/B-VI were used for the pseudo fission product data of U-235, U-238, Pu-239, Pu-240, Pu-241, and Pu-242. The pseudo fission product data can be used with the KAFAX-F22 or -E66, which are the MATXS-format libraries for analyses of the liquid metal fast reactor at KAERI and were distributed through the OECD/NEA. The 80-group MATXS-format libraries of the 172 fission products were generated and the burnup chains for generation of the pseudo fission products were prepared.

  19. Analysis of simulated high burnup nuclear fuel by laser induced breakdown spectroscopy

    Science.gov (United States)

    Singh, Manjeet; Sarkar, Arnab; Banerjee, Joydipta; Bhagat, R. K.

    2017-06-01

    Advanced Heavy Water Reactor (AHWR) grade (Th-U)O2 fuel sample and Simulated High Burn-Up Nuclear Fuels (SIMFUEL) samples mimicking the 28 and 43 GWd/Te irradiated burn-up fuel were studied using laser-induced breakdown spectroscopy (LIBS) setup in a simulated hot-cell environment from a distance of > 1.5 m. Resolution of 60 emission lines of fission products was identified. Among them only a few emission lines were found to generate calibration curves. The study demonstrates the possibility to investigate impurities at concentrations around hundreds of ppm, rapidly at atmospheric pressure without any sample preparation. The results of Ba and Mo showed the advantage of LIBS analysis over traditional methods involving sample dissolution, which introduces possible elemental loss. Limits of detections (LOD) under Ar atmosphere shows significant improvement, which is shown to be due to the formation of stable plasma.

  20. Experience with incomplete control rod insertion in fuel with burnup exceeding approximately 40 GWD/MTU

    Energy Technology Data Exchange (ETDEWEB)

    Kee, E. [Houston Lighting & Power Co., Wadworth, TX (United States)

    1997-01-01

    Analysis and measurement experience with fuel assemblies having incomplete control rod insertion at burnups of approximately 40 GWD/MTU is presented. Control rod motion dynamics and simplified structural analyses are presented and compared to measurement data. Fuel assembly growth measurements taken with the plant Refueling Machine Z-Tape are described and presented. Bow measurements (including plug gauging) are described and potential improvements are suggested. The measurements described and analysis performed show that sufficient guide tube bow (either from creep or yield buckling) is present in some high burnup assemblies to stop the control rods before they reach their full limit of travel. Recommendations are made that, if implemented, could improve cost performance related to testing and analysis activities.

  1. The Impact of Operating Parameters and Correlated Parameters for Extended BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Marshall, William B. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ilas, Germina [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Betzler, Benjamin R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bowman, Stephen M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-06-01

    Applicants for certificates of compliance for spent nuclear fuel (SNF) transportation and dry storage systems perform analyses to demonstrate that these systems are adequately subcritical per the requirements of Title 10 of the Code of Federal Regulations (10 CFR) Parts 71 and 72. For pressurized water reactor (PWR) SNF, these analyses may credit the reduction in assembly reactivity caused by depletion of fissile nuclides and buildup of neutron-absorbing nuclides during power operation. This credit for reactivity reduction during depletion is commonly referred to as burnup credit (BUC). US Nuclear Regulatory Commission (NRC) staff review BUC analyses according to the guidance in the Division of Spent Fuel Storage and Transportation Interim Staff Guidance (ISG) 8, Revision 3, Burnup Credit in the Criticality Safety Analyses of PWR Spent Fuel in Transportation and Storage Casks.

  2. Investigation of burnup credit allowance in the criticality safety evaluation of spent fuel casks

    Energy Technology Data Exchange (ETDEWEB)

    Lake, W.H. (USDOE, Washington, DC (USA)); Sanders, T.L. (Sandia National Labs., Albuquerque, NM (USA)); Parks, C.V. (Oak Ridge National Lab., TN (USA))

    1990-01-01

    This presentation discusses work in progress on criticality analysis verification for designs which take account of the burnup and age of transported fuel. The work includes verification of cross section data, correlation with experiments, proper extension of the methods into regimes not covered by experiments, establishing adequate reactivity margins, and complete documentation of the project. Recommendations for safe operational procedures are included, as well as a discussion of the economic and safety benefits of such designs.

  3. Analysis of Experimental Data for High Burnup PWR Spent Fuel Isotopic Validation - Vandellos II Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ilas, Germina [ORNL; Gauld, Ian C [ORNL

    2011-01-01

    This report is one of the several recent NUREG/CR reports documenting benchmark-quality radiochemical assay data and the use of the data to validate computer code predictions of isotopic composition for spent nuclear fuel, to establish the uncertainty and bias associated with code predictions. The experimental data analyzed in the current report were acquired from a high-burnup fuel program coordinated by Spanish organizations. The measurements included extensive actinide and fission product data of importance to spent fuel safety applications, including burnup credit, decay heat, and radiation source terms. Six unique spent fuel samples from three uranium oxide fuel rods were analyzed. The fuel rods had a 4.5 wt % {sup 235}U initial enrichment and were irradiated in the Vandellos II pressurized water reactor operated in Spain. The burnups of the fuel samples range from 42 to 78 GWd/MTU. The measurements were used to validate the two-dimensional depletion sequence TRITON in the SCALE computer code system.

  4. Estimation of the Fuel Depletion Code Bias and Uncertainty in Burnup-Credit Criticality Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Woon; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Lee, Sang Jin; Bae, Chang Yeal [Nuclear Environment Technology Institute, Taejon (Korea, Republic of)

    2006-07-01

    In the past, criticality safety analyses for commercial light-water-reactor (LWR) spent nuclear fuel (SNF) storage and transportation canisters assumed the spent fuel to be fresh (unirradiated) fuel with uniform isotopic compositions. This fresh-fuel assumption provides a well-defined, bounding approach to the criticality safety analysis that eliminates concerns related to the fuel operating history, and thus considerably simplifies the safety analysis. However, because this assumption ignores the inherent decrease in reactivity as a result of irradiation, it is very conservative. The concept of taking credit for the reduction in reactivity due to fuel burnup is commonly referred to as burnup credit. Implementation of burnup credit requires the computational prediction of the nuclide inventories (compositions) for the dominant fissile and absorbing nuclide species in spent fuel. In addition to that, the bias and uncertainty in the predicted concentration of all nuclides used in the analysis be established by comparisons of calculated and measured radiochemical assay data. In this paper, three methods for considering the bias and uncertainty will be reviewed. The estimated bias and uncertainty that the results of 3rd method are presented.

  5. AREVA NP burnup credit investigation on irradiated MOX fuel within the REBUS BWR programme

    Energy Technology Data Exchange (ETDEWEB)

    Alander, Alexandra; Misu, Stefan; Timm, Wolf [AREVA, AREVA NP, Erlangen (Germany); Thareau, Sebastien [AREVA, AREVA NP, Paris (France)

    2008-07-01

    The present paper summarizes a criticality and burnup credit investigation carried out using the 2D spectral codes CASMO-4 and APOLLO2-A. Fission rate distributions and multiplication factors, for UOX and MOX configurations, are calculated as well as the reactivity effect caused by burnup on a selection of irradiated MOX fuel assemblies. 3D core criticality calculations were carried out with the Monte Carlo transport code MOCA and the deterministic transport code VARIANT (a nodal code developed by ANL) using CASMO-4 generated cross section libraries. Calculations were compared to experimental data from the critical facility VENUS in the context of the REBUS BWR Programme. The results confirm that the spectral codes CASMO-4 and APOLLO2-A are well suited to calculate fission rates, multiplication factors and reactivity effects. It is also found that the calculated burnup reactivity effect, using CASMO-4 generated cross sections and the best 3D method (MOCA), is underestimated by merely 7% compared to the experimental value, which can mainly be attributed to the simplifications done in order to model the critical configurations with reasonable efforts. (authors)

  6. Burnup simulations of different fuel grades using the MCNPX Monte Carlo code

    Directory of Open Access Journals (Sweden)

    Asah-Opoku Fiifi

    2014-01-01

    Full Text Available Global energy problems range from the increasing cost of fuel to the unequal distribution of energy resources and the potential climate change resulting from the burning of fossil fuels. A sustainable nuclear energy would augment the current world energy supply and serve as a reliable future energy source. This research focuses on Monte Carlo simulations of pressurized water reactor systems. Three different fuel grades - mixed oxide fuel (MOX, uranium oxide fuel (UOX, and commercially enriched uranium or uranium metal (CEU - are used in this simulation and their impact on the effective multiplication factor (Keff and, hence, criticality and total radioactivity of the reactor core after fuel burnup analyzed. The effect of different clad materials on Keff is also studied. Burnup calculation results indicate a buildup of plutonium isotopes in UOX and CEU, as opposed to a decline in plutonium radioisotopes for MOX fuel burnup time. For MOX fuel, a decrease of 31.9% of the fissile plutonium isotope is observed, while for UOX and CEU, fissile plutonium isotopes increased by 82.3% and 83.8%, respectively. Keff results show zircaloy as a much more effective clad material in comparison to zirconium and stainless steel.

  7. Needs of reliable nuclear data and covariance matrices for Burnup Credit in JEFF-3 library

    Directory of Open Access Journals (Sweden)

    Lecarpentier D.

    2013-03-01

    Full Text Available Burnup Credit (BUC is the concept which consists in taking into account credit for the reduction of nuclear spent fuel reactivity due to its burnup. In the case of PWR-MOx spent fuel, studies pointed out that the contribution of the 15 most absorbing, stable and non-volatile fission products selected to the credit is as important as the one of the actinides. In order to get a “best estimate” value of the keff, biases of their inventory calculation and individual reactivity worth should be considered in criticality safety studies. This paper enhances the most penalizing bias towards criticality and highlights possible improvements of nuclear data for the 15 FPs of PWRMOx BUC. Concerning the fuel inventory, trends in function of the burnup can be derived from experimental validation of the DARWIN-2.3 package (using the JEFF-3.1.1/SHEM library. Thanks to the BUC oscillation programme of separated FPs in the MINERVE reactor and fully validated scheme PIMS, calculation over experiment ratios can be accurately transposed to tendencies on the FPs integral cross sections.

  8. Study on nuclear physics of high burnup full MOX PWR core

    Energy Technology Data Exchange (ETDEWEB)

    Kugo, Teruhiko; Shimada, Syoichiro; Okubo, Tsutomu; Ochiai, Masaaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    As one of options for future light water reactors, we have been studying a new concept of a high burnup full MOX PWR core. We have proposed a core of 600 MWe to ensure discharged burnup of 100 GWd/t by increasing a moderator to fuel volume ratio to 2.6 with enlarged fuel pin pitch of 13.8 mm, and have investigated its feasibility in neutronics. A plutonium fissile content of 12% is needed for this core. A soluble boric acid with B-10 enrichment of 40% is able to control burnup reactivity without increasing a capacity of boron tanks. A control rod cluster with use of natural boron carbide (B{sub 4}C) per three fuel assemblies ensures a shutdown margin of more than 2%dk/kk`. A moderator temperature and void coefficients are negative through an operating cycle. Although the use of burnable poisons like Gd{sub 2}O{sub 3} and Er{sub 2}O{sub 3} is not necessary to reduce an excess reactivity, it can lower a radial power peaking factor by about 0.1. (author)

  9. High burnup performance of Mg, Mg-Nb and Ti doped UO{sub 2} fuels

    Energy Technology Data Exchange (ETDEWEB)

    Shiratori, Tetsuo; Serizawa, Hiroyuki; Fukuda, Kousaku [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Fujino, Takeo; Sato, Nobuaki; Yamada, Kohta [Institute for Advanced Materials Processing, Tohoku Univ., Sendai, Miyagi (Japan)

    2000-09-01

    In order to control irradiation performance of fuel swelling and FP gas release etc. at high burnups of light water reactor fuels, doped UO{sub 2} pellet fuels were prepared and their irradiation behavior was examined. The UO{sub 2} pellets doped 2.5 to 15mol%Mg, 5mol%Mg - 5mol%Nb, and 3.5mol%Ti and undoped UO{sub 2} pellets as a reference fuel were loaded together in a capsule and irradiated to the maximum burnups of 94GWd/t(U) below temperature of 1000degC in the JRR-3M reactor of JAERI. As results of post-irradiation examinations such as visual inspection, dimensional and density change measurements, thermal diffusivity and ceramography with optical microscope and EPMA, no difference was observed between the doped and the reference UO{sub 2} fuels. And valuable results were obtained on high burnup properties for swelling rates, thermal conductivities, structure changes and so on. (author)

  10. Thermal Hydraulic Analysis of 3 MW TRIGA Research Reactor of Bangladesh Considering Different Cycles of Burnup

    Directory of Open Access Journals (Sweden)

    M.H. Altaf

    2014-12-01

    Full Text Available Burnup dependent steady state thermal hydraulic analysis of TRIGA Mark-II research reactor has been carried out utilizing coupled point kinetics, neutronics and thermal hydraulics code EUREKA-2/RR. From the previous calculations of neutronics parameters including percentage burnup of individual fuel elements performed so far for 700 MWD burnt core of TRIGA reactor showed that the fuel rod predicted as hottest at the beginning of cycle (fresh core was found to remain as the hottest until 200 MWD of burn, but, with the progress of core burn, the hottest rod was found to be shifted and another rod in the core became the hottest. The present study intends to evaluate the thermal hydraulic parameters of these hottest fuel rods at different cycles of burnup, from beginning to 700 MWD core burnt considering reactor operates under steady state condition. Peak fuel centerline temperature, maximum cladding and coolant temperatures of the hottest channels were calculated. It revealed that maximum temperature reported for fuel clad and fuel centerline found to lie below their melting points which indicate that there is no chance of burnout on the fuel cladding surface and no blister in the fuel meat throughout the considered cycles of core burnt.

  11. Irradiation performance of PFBR MOX fuel after 112 GWd/t burn-up

    Energy Technology Data Exchange (ETDEWEB)

    Venkiteswaran, C.N., E-mail: cnv@igcar.gov.in; Jayaraj, V.V.; Ojha, B.K.; Anandaraj, V.; Padalakshmi, M.; Vinodkumar, S.; Karthik, V.; Vijaykumar, Ran; Vijayaraghavan, A.; Divakar, R.; Johny, T.; Joseph, Jojo; Thirunavakkarasu, S.; Saravanan, T.; Philip, John; Rao, B.P.C.; Kasiviswanathan, K.V.; Jayakumar, T.

    2014-06-01

    The 500 MWe Prototype Fast Breeder Reactor (PFBR) which is in advanced stage of construction at Kalpakkam, India, will use mixed oxide (MOX) fuel with a target burnup of 100 GWd/t. The fuel pellet is of annular design to enable operation at a peak linear power of 450 W/cm with the requirement of minimum duration of pre-conditioning. The performance of the MOX fuel and the D9 clad and wrapper material was assessed through Post Irradiation Examinations (PIE) after test irradiation of 37 fuel pin subassembly in Fast Breeder Test Reactor (FBTR) to a burn-up of 112 GWd/t. Fission product distribution, swelling and fuel–clad gap evolution, central hole diameter variation, restructuring, fission gas release and clad wastage due to fuel–clad chemical interaction were evaluated through non-destructive and destructive examinations. The examinations have indicated that the MOX fuel can safely attain the desired target burn-up in PFBR.

  12. Underestimation of nuclear fuel burnup – theory, demonstration and solution in numerical models

    Directory of Open Access Journals (Sweden)

    Gajda Paweł

    2016-01-01

    Full Text Available Monte Carlo methodology provides reference statistical solution of neutron transport criticality problems of nuclear systems. Estimated reaction rates can be applied as an input to Bateman equations that govern isotopic evolution of reactor materials. Because statistical solution of Boltzmann equation is computationally expensive, it is in practice applied to time steps of limited length. In this paper we show that simple staircase step model leads to underprediction of numerical fuel burnup (Fissions per Initial Metal Atom – FIMA. Theoretical considerations indicates that this error is inversely proportional to the length of the time step and origins from the variation of heating per source neutron. The bias can be diminished by application of predictor-corrector step model. A set of burnup simulations with various step length and coupling schemes has been performed. SERPENT code version 1.17 has been applied to the model of a typical fuel assembly from Pressurized Water Reactor. In reference case FIMA reaches 6.24% that is equivalent to about 60 GWD/tHM of industrial burnup. The discrepancies up to 1% have been observed depending on time step model and theoretical predictions are consistent with numerical results. Conclusions presented in this paper are important for research and development concerning nuclear fuel cycle also in the context of Gen4 systems.

  13. OECD/NEA burnup credit criticality benchmark. Result of phase IIA

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Makoto; Okuno, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    The report describes the final result of the Phase IIA of the Burnup Credit Criticality Benchmark conducted by OECD/NEA. In the Phase IIA benchmark problems, the effect of an axial burnup profile of PWR spent fuels on criticality (end effect) has been studied. The axial profiles at 10, 30 and 50 GWd/t burnup have been considered. In total, 22 results from 18 institutes of 10 countries have been submitted. The calculated multiplication factors from the participants have lain within the band of {+-} 1% {Delta}k. For the irradiation up to 30 GWd/t, the end effect has been found to be less than 1.0% {Delta}k. But, for the 50 GWd/t case, the effect is more than 4.0% {Delta}k when both actinides and FPs are taken into account, whereas it remains less than 1.0% {Delta}k when only actinides are considered. The fission density data have indicated the importance end regions have in the criticality safety analysis of spent fuel systems. (author).

  14. Preliminary 3D burn-up analysis of the HPLWR core

    Energy Technology Data Exchange (ETDEWEB)

    Monti, Lanfranco; Gabrielli, Fabrizio; Schulenberg, Thomas [Forschungszentrum Karlsruhe (Germany). Inst. for Nuclear and Energy Technologies

    2009-07-01

    The High Performance Light Water Reactor (HPLWR) is an innovative reactor concept cooled and moderated with water at supercritical pressure (25 MPa) whose feasibility is analyzed within a European framework [1]. The pronounced variation in water density, which takes place inside the core, is due to the coolant heat up from 550 K to 800 K and is supposed to generate pronounced 3D effects during reactor operation because the different core regions have different flux amplitude and neutron spectrum. Open questions are how k{sub eff} and the power-map will change during the burn-up and require a 3D multi-zone burn-up analysis of the core. This goal is achieved using the ERANOS system [2, 3], which is a deterministic tool for neutronic core analyses. The starting condition is taken from a neutronic/thermal-hydraulic coupled solution of the whole core [4], which does not yet include any fuel enrichment optimization nor reactivity control systems, i.e. control rods or burnable poisons. Uranium dioxide enriched to 5wt% in {sup 235}U is used as starting fuel while typical LWRs evolution chains for actinides and fission products have been selected. The core nodalization used in the coupled system is also adopted for multi-zone burn-up analysis: there are 462 zones with different material composition, 21 in axial direction and 22 in the horizontal plane. A burn-up period of 200 days ({approx_equal}6400 MWd/tHM) is considered here and has been divided into two different smaller time steps: 1) an inner time step at which macroscopic cross-sections (XSs) and the flux normalization are calculated according to the change in fuel isotopic composition; 2) an outer time step at which whole core flux calculations are performed to evaluate the region-wise neutron flux distribution. The length of the flux calculation time step has to be short enough to avoid unphysical power-shape oscillations, as underlined by Reiss et al. [5] with a different computational approach. The 40 groups

  15. Microhardness and Young's modulus of high burn-up UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Cappia, F. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Technische Universität München, Faculty of Mechanical Engineering, Department of Nuclear Engineering, D-85748, Garching bei München (Germany); Pizzocri, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Politecnico di Milano, Department of Energy, Nuclear Engineering Division, 20156, Milano (Italy); Marchetti, M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Université Montpellier 2, Institut d’Electronique du Sud UMR CNRS 5214, 34095, Montpellier (France); Schubert, A.; Van Uffelen, P. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Luzzi, L. [Politecnico di Milano, Department of Energy, Nuclear Engineering Division, 20156, Milano (Italy); Papaioannou, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Macián-Juan, R. [Technische Universität München, Faculty of Mechanical Engineering, Department of Nuclear Engineering, D-85748, Garching bei München (Germany); Rondinella, V.V., E-mail: Vincenzo.RONDINELLA@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany)

    2016-10-15

    Vickers microhardness (HV{sub 0.1}) and Young's modulus (E) measurements of LWR UO{sub 2} fuel at burn-up ≥60 GWd/tHM are presented. Their ratio HV{sub 0.1}/E was found constant in the range 60–110 GWd/tHM. From the ratio and the microhardness values vs porosity, the Young's modulus dependence on porosity was derived and extended to the full radial profile, including the high burn-up structure (HBS). The dependence is well represented by a linear correlation. The data were compared to fuel performance codes correlations. A burn-up dependent factor was introduced in the Young's modulus expression. The modifications extend the experimental validation range of the TRANSURANUS correlation from un-irradiated to irradiated UO{sub 2} and up to 20% porosity. First simulations of LWR fuel rod irradiations were performed in order to illustrate the impact on fuel performance. In the specific cases selected, the simulations suggest a limited effect of the Young's modulus decrease due to burn-up on integral fuel performance. - Highlights: • Vickers microhardness and Young's modulus data of high burnup fuels are presented. • The data are compared to fuel performance codes' correlations. • A burn-up dependent factor is introduced for the Young's modulus of irradiated fuel. • The modification extends ranges of experimental validation of the code correlation. • The new burn-up dependent factor has limited effect on integral fuel performance.

  16. Criticality Analysis of Assembly Misload in a PWR Burnup Credit Cask

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, J. C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2008-01-31

    The Interim Staff Guidance on bumup credit (ISG-8) for spent fuel in storage and transportation casks, issued by the Nuclear Regulatory Commission's Spent Fuel Project Office, recommends a bumup measurement for each assembly to confirm the reactor record and compliance with the assembly bumup value used for loading acceptance. This recommendation is intended to prevent unauthorized loading (misloading) of assemblies due to inaccuracies in reactor burnup records and/or improper assembly identification, thereby ensuring that the appropriate subcritical margin is maintained. This report presents a computational criticality safety analysis of the consequences of misloading fuel assemblies in a highcapacity cask that relies on burnup credit for criticality safety. The purpose of this report is to provide a quantitative understanding of the effects of fuel misloading events on safety margins. A wide variety of fuel-misloading configurations are investigated and results are provided for informational purposes. This report does not address the likelihood of occurrence for any of the misload configurations considered. For representative, qualified bumup-enrichment combinations, with and without fission products included, misloading two assemblies that are underburned by 75% results in an increase in keff of 0.025-0.045, while misloading four assemblies that are underburned by 50% also results in an increase in keff of 0.025-0.045. For the cask and conditions considered, a reduction in bumup of 20% in all assemblies results in an increase in kff of less than 0.035. Misloading a single fresh assembly with 3, 4, or 5 wt% 235U enrichment results in an increase in keffof--0.02, 0.04, or 0.06, respectively. The report concludes with a summary of these and other important findings, as well as a discussion of relevant issues that should be considered when assessing the appropriate role of burnup measurements.

  17. Image-Based Chemical Structure Determination.

    Science.gov (United States)

    Ofner, Johannes; Brenner, Florian; Wieland, Karin; Eitenberger, Elisabeth; Kirschner, Johannes; Eisenmenger-Sittner, Christoph; Török, Szilvia; Döme, Balazs; Konegger, Thomas; Kasper-Giebl, Anne; Hutter, Herbert; Friedbacher, Gernot; Lendl, Bernhard; Lohninger, Hans

    2017-07-28

    Chemical imaging is a powerful tool for understanding the chemical composition and nature of heterogeneous samples. Recent developments in elemental, vibrational, and mass-spectrometric chemical imaging with high spatial resolution (50-200 nm) and reasonable timescale (a few hours) are capable of providing complementary chemical information about various samples. However, a single technique is insufficient to provide a comprehensive understanding of chemically complex materials. For bulk samples, the combination of different analytical methods and the application of statistical methods for extracting correlated information across different techniques is a well-established and powerful concept. However, combined multivariate analytics of chemical images obtained via different imaging techniques is still in its infancy, hampered by a lack of analytical methodologies for data fusion and analysis. This study demonstrates the application of multivariate statistics to chemical images taken from the same sample via various methods to assist in chemical structure determination.

  18. Reactors as a Source of Antineutrinos: Effects of Fuel Loading and Burnup for Mixed-Oxide Fuels

    Science.gov (United States)

    Bernstein, Adam; Bowden, Nathaniel S.; Erickson, Anna S.

    2018-01-01

    In a conventional light-water reactor loaded with a range of uranium and plutonium-based fuel mixtures, the variation in antineutrino production over the cycle reflects both the initial core fissile inventory and its evolution. Under an assumption of constant thermal power, we calculate the rate at which antineutrinos are emitted from variously fueled cores, and the evolution of that rate as measured by a representative ton-scale antineutrino detector. We find that antineutrino flux decreases with burnup for low-enriched uranium cores, increases for full mixed-oxide (MOX) cores, and does not appreciably change for cores with a MOX fraction of approximately 75%. Accounting for uncertainties in the fission yields in the emitted antineutrino spectra and the detector response function, we show that the difference in corewide MOX fractions at least as small as 8% can be distinguished using a hypothesis test. The test compares the evolution of the antineutrino rate relative to an initial value over part or all of the cycle. The use of relative rates reduces the sensitivity of the test to an independent thermal power measurement, making the result more robust against possible countermeasures. This rate-only approach also offers the potential advantage of reducing the cost and complexity of the antineutrino detectors used to verify the diversion, compared to methods that depend on the use of the antineutrino spectrum. A possible application is the verification of the disposition of surplus plutonium in nuclear reactors.

  19. Thermal diffusivity of homogeneous SBR MOX fuel with a burn-up of 35 MWd/kgHM

    Science.gov (United States)

    Cozzo, C.; Staicu, D.; Pagliosa, G.; Papaioannou, D.; Rondinella, V. V.; Konings, R. J. M.; Walker, C. T.; Barker, M. A.; Hervé, P.

    2010-05-01

    The effect of burn-up on the thermal conductivity of homogeneous SBR MOX fuel is investigated and compared with standard UO 2 LWR fuel. New thermal diffusivity results obtained on SBR MOX fuel with a pellet burn-up of 35 MWd/kgHM are reported. The thermal diffusivity measurements were carried out at three radial positions using a shielded "laser-flash" device and show that the thermal diffusivity increases from the pellet periphery to the centre. The fuel thermal conductivity was found to be in the same range as for UO 2 of similar burn-up. The annealing behaviour was characterized in order to identify the degradation due to the out-of-pile auto-irradiation.

  20. Thermal diffusivity of homogeneous SBR MOX fuel with a burn-up of 35 MWd/kgHM

    Energy Technology Data Exchange (ETDEWEB)

    Cozzo, C. [European Commission, Joint Research Centre, Institute for Transuranium Element, P.O. Box 2340, D-76125 Karlsruhe (Germany); Staicu, D., E-mail: dragos.staicu@ec.europa.e [European Commission, Joint Research Centre, Institute for Transuranium Element, P.O. Box 2340, D-76125 Karlsruhe (Germany); Pagliosa, G.; Papaioannou, D.; Rondinella, V.V.; Konings, R.J.M.; Walker, C.T. [European Commission, Joint Research Centre, Institute for Transuranium Element, P.O. Box 2340, D-76125 Karlsruhe (Germany); Barker, M.A. [The UK' s National Nuclear Laboratory Ltd., Central Laboratory, Sellafield, Seascale, Cumbria CA20 1PG (United Kingdom); Herve, P. [LEEE, University Paris X, 1 Chemin Desvalliere, 92410 Ville d' Avray (France)

    2010-05-31

    The effect of burn-up on the thermal conductivity of homogeneous SBR MOX fuel is investigated and compared with standard UO{sub 2} LWR fuel. New thermal diffusivity results obtained on SBR MOX fuel with a pellet burn-up of 35 MWd/kgHM are reported. The thermal diffusivity measurements were carried out at three radial positions using a shielded 'laser-flash' device and show that the thermal diffusivity increases from the pellet periphery to the centre. The fuel thermal conductivity was found to be in the same range as for UO{sub 2} of similar burn-up. The annealing behaviour was characterized in order to identify the degradation due to the out-of-pile auto-irradiation.

  1. Uncertainty Propagation Analysis for PWR Burnup Pin-Cell Benchmark by Monte Carlo Code McCARD

    Directory of Open Access Journals (Sweden)

    Ho Jin Park

    2012-01-01

    Full Text Available In the Monte Carlo (MC burnup analyses, the uncertainty of a tally estimate at a burnup step may be induced from four sources: the statistical uncertainty caused by a finite number of simulations, the nuclear covariance data, uncertainties of number densities, and cross-correlations between the nuclear data and the number densities. In this paper, the uncertainties of kinf, reaction rates, and number densities for a PWR pin-cell benchmark problem are quantified by an uncertainty propagation formulation in the MC burnup calculations. The required sensitivities of tallied parameters to the microscopic cross-sections and the number densities are estimated by the MC differential operator sampling method accompanied by the fission source perturbation. The uncertainty propagation analyses are conducted with two nuclear covariance data—ENDF/B-VII.1 and SCALE6.1/COVA libraries—and the numerical results are compared with each other.

  2. Fuel burnup analysis for IRIS reactor using MCNPX and WIMS-D5 codes

    Science.gov (United States)

    Amin, E. A.; Bashter, I. I.; Hassan, Nabil M.; Mustafa, S. S.

    2017-02-01

    International Reactor Innovative and Secure (IRIS) reactor is a compact power reactor designed with especial features. It contains Integral Fuel Burnable Absorber (IFBA). The core is heterogeneous both axially and radially. This work provides the full core burn up analysis for IRIS reactor using MCNPX and WIMDS-D5 codes. Criticality calculations, radial and axial power distributions and nuclear peaking factor at the different stages of burnup were studied. Effective multiplication factor values for the core were estimated by coupling MCNPX code with WIMS-D5 code and compared with SAS2H/KENO-V code values at different stages of burnup. The two calculation codes show good agreement and correlation. The values of radial and axial powers for the full core were also compared with published results given by SAS2H/KENO-V code (at the beginning and end of reactor operation). The behavior of both radial and axial power distribution is quiet similar to the other data published by SAS2H/KENO-V code. The peaking factor values estimated in the present work are close to its values calculated by SAS2H/KENO-V code.

  3. X-Ray Pulsar Based Navigation and Time Determination Project

    Data.gov (United States)

    National Aeronautics and Space Administration — DARPA recently initiated the XNAV program to undertake development of GPS independent, precision navigation and time determination based on observations of certain...

  4. Analyses of PWR spent fuel composition using SCALE and SWAT code systems to find correction factors for criticality safety applications adopting burnup credit

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hee Sung; Suyama, Kenya; Mochizuki, Hiroki; Okuno, Hiroshi; Nomura, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-01-01

    The isotopic composition calculations were performed for 26 spent fuel samples from the Obrigheim PWR reactor and 55 spent fuel samples from 7 PWR reactors using the SAS2H module of the SCALE4.4 code system with 27, 44 and 238 group cross-section libraries and the SWAT code system with the 107 group cross-section library. For the analyses of samples from the Obrigheim PWR reactor, geometrical models were constructed for each of SCALE4.4/SAS2H and SWAT. For the analyses of samples from 7 PWR reactors, the geometrical model already adopted in the SCALE/SAS2H was directly converted to the model of SWAT. The four kinds of calculation results were compared with the measured data. For convenience, the ratio of the measured to calculated values was used as a parameter. When the ratio is less than unity, the calculation overestimates the measurement, and the ratio becomes closer to unity, they have a better agreement. For many important nuclides for burnup credit criticality safety evaluation, the four methods applied in this study showed good coincidence with measurements in general. More precise observations showed, however: (1) Less unity ratios were found for Pu-239 and -241 for selected 16 samples out of the 26 samples from the Obrigheim reactor (10 samples were deselected because their burnups were measured with Cs-137 non-destructive method, less reliable than Nd-148 method the rest 16 samples were measured with); (2) Larger than unity ratios were found for Am-241 and Cm-242 for both the 16 and 55 samples; (3) Larger than unity ratios were found for Sm-149 for the 55 samples; (4) SWAT was generally accompanied by larger ratios than those of SAS2H with some exceptions. Based on the measured-to-calculated ratios for 71 samples of a combined set in which 16 selected samples and 55 samples were included, the correction factors that should be multiplied to the calculated isotopic compositions were generated for a conservative estimate of the neutron multiplication factor

  5. 78 FR 67348 - Invitation for Public Comment on Draft Test Plan for the High Burnup Dry Storage Cask Research...

    Science.gov (United States)

    2013-11-12

    ... Invitation for Public Comment on Draft Test Plan for the High Burnup Dry Storage Cask Research and Development Project (CDP) AGENCY: Fuel Cycle Technologies, Office of Nuclear Energy, Department of Energy... multiple entities while comments are resolved. Dated: November 5, 2013. Jay Jones, Office of Fuel Cycle...

  6. Reducing the fuel temperature for pressure-tube supercritical-water-cooled reactors and the effect of fuel burnup

    Energy Technology Data Exchange (ETDEWEB)

    Nichita, E., E-mail: eleodor.nichita@uoit.ca; Kovaltchouk, V., E-mail: vitali.kovaltchouk@uoit.ca

    2015-12-15

    Highlights: • Typical PT-SCWR fuel uses single-region pins consisting of a homogeneous mixture of ThO{sub 2} and PuO{sub 2}. • Using two regions (central for the ThO{sub 2} and peripheral for the PuO{sub 2}) reduces the fuel temperature. • Single-region-pin melting-to-average power ratio is 2.5 at 0.0 MW d/kg and 2.3 at 40 MW d/kg. • Two-region-pin melting-to-average power ratio is 36 at 0.0 MW d/kg and 10.5 at 40 MW d/kg. • Two-region-pin performance drops with burnup due to fissile-element buildup in the ThO{sub 2} region. - Abstract: The Pressure-Tube Supercritical-Water-Cooled Reactor (PT-SCWR) is one of the concepts under investigation by the Generation IV International Forum for its promise to deliver higher thermal efficiency than nuclear reactors currently in operation. The high coolant temperature (>625 K) and high linear power density employed by the PT-SCWR cause the fuel temperature to be fairly high, leading to a reduced margin to fuel melting, thus increasing the risk of actual melting during accident scenarios. It is therefore desirable to come up with a fuel design that lowers the fuel temperature while preserving the high linear power ratio and high coolant temperature. One possible solution is to separate the fertile (ThO{sub 2}) and fissile (PuO{sub 2}) fuel materials into different radial regions in each fuel pin. Previously-reported work found that by locating the fertile material at the centre and the fissile material at the periphery of the fuel pin, the fuel centreline temperature can be reduced by ∼650 K for fresh fuel compared to the case of a homogeneous (Th–Pu)O{sub 2} mixture for the same coolant temperature and linear power density. This work provides a justification for the observed reduction in fuel centreline temperature and suggests a systematic approach to lower the fuel temperature. It also extends the analysis to the dependence of the radial temperature profile on fuel burnup. The radial temperature profile is

  7. Applicability of the MCNP-ACAB system to inventory prediction in high-burnup fuels: sensitivity/uncertainty estimates

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Herranz, N.; Cabellos, O. [Madrid Polytechnic Univ., Dept. of Nuclear Engineering (Spain); Cabellos, O.; Sanz, J. [Madrid Polytechnic Univ., 2 Instituto de Fusion Nuclear (Spain); Sanz, J. [Univ. Nacional Educacion a Distancia, Dept. of Power Engineering, Madrid (Spain)

    2005-07-01

    We present a new code system which combines the Monte Carlo neutron transport code MCNP-4C and the inventory code ACAB as a suitable tool for high burnup calculations. Our main goal is to show that the system, by means of ACAB capabilities, enables us to assess the impact of neutron cross section uncertainties on the inventory and other inventory-related responses in high burnup applications. The potential impact of nuclear data uncertainties on some response parameters may be large, but only very few codes exist which can treat this effect. In fact, some of the most reported effective code systems in dealing with high burnup problems, such as CASMO-4, MCODE and MONTEBURNS, lack this capability. As first step, the potential of our system, ruling out the uncertainty capability, has been compared with that of those code systems, using a well referenced high burnup pin-cell benchmark exercise. It is proved that the inclusion of ACAB in the system allows to obtain results at least as reliable as those obtained using other inventory codes, such as ORIGEN2. Later on, the uncertainty analysis methodology implemented in ACAB, including both the sensitivity-uncertainty method and the uncertainty analysis by the Monte Carlo technique, is applied to this benchmark problem. We estimate the errors due to activation cross section uncertainties in the prediction of the isotopic content up to the high-burnup spent fuel regime. The most relevant uncertainties are remarked, and some of the most contributing cross sections to those uncertainties are identified. For instance, the most critical reaction for Am{sup 242m} is Am{sup 241}(n,{gamma}-m). At 100 MWd/kg, the cross-section uncertainty of this reaction induces an error of 6.63% on the Am{sup 242m} concentration.The uncertainties in the inventory of fission products reach up to 30%.

  8. Hydrides reorientation investigation of high burn-up PWR fuel cladding

    Science.gov (United States)

    Valance, Stéphane; Bertsch, Johannes

    2015-09-01

    The direction of formation of hydride in fuel cladding tube is a major issue for the assessment of the cladding remaining ductility after service. This behavior is quite well known for fresh material, but few results exist for irradiated material. The reorientation behavior of a Zircaloy-4 fuel cladding (AREVA duplex DX-D4) at a burn-up of around 72 GWd t-1 is investigated here. The increase of the fraction of reoriented hydrides through repeated thermo-mechanical loading is inspected; as well, the possibility to recover a state with a minimized quantity of reoriented hydrides is tested using pure thermal loading cycles. The study is completed by a qualitative assessment of the hydrogen density in the duplex layer, where a dependence of the hydrides density on the hoop stress state is observed.

  9. Monte Carlo calculations of the REBUS critical experiment for validation of burn-up credit

    Energy Technology Data Exchange (ETDEWEB)

    Hennebach, M.; Kuhl, H. [WTI GmbH, Julich (Germany)

    2008-07-01

    The REBUS experiment is a valuable benchmark for the validation of Monte Carlo criticality codes within the context of burn-up credit. It investigates the difference in reactivity worth of unirradiated fuel rods and of fuel rods irradiated in a PWR. This paper presents results of criticality calculations for this experiment with the Monte Carlo codes MCNP and SCALE/KENO. The results show that even the comparatively small reactivity loss of about 2000 pcm measured in this experiment can be calculated within an accuracy of 6 per cent. A detailed comparison of measured and calculated core characteristics (fission rate and flux distributions) shows good agreement, which indicates an adequately detailed model geometry for criticality calculations. The slight underestimation (500 pcm) of absolute k(eff) values is not out of the typical range for criticality benchmark experiments.

  10. Fuel modeling at high burn-up: recent development of the GERMINAL code

    Science.gov (United States)

    Melis, J.-C.; Piron, J.-P.; Roche, L.

    1993-09-01

    In the frame of research and development on fast breeder reactors fuels, CEA/DEC is developing the computer code GERMINAL to study fuel pin thermal and mechanical behaviour during steady-state and accidental conditions. The development of the GERMINAL 1 code is foreseen in two steps: (1) The GERMINAL 1-1 version which is presently delivered fully documented with a physical qualification guaranteed up to 8 at%. (2) The GERMINAL 1-2 version which, in addition to what is presently treated in GERMINAL 1-1, includes the treatment of high burn-up effects on the the fission gas release and the fuel-clad interface (called JOG). The validation of GERMINAL 1-2 is presently in progress and will include specific experiments (JOG tests) performed in the CABRI reactor.

  11. Accident source terms for boiling water reactors with high burnup cores.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Leonard, Mark Thomas

    2007-11-01

    The primary objective of this report is to provide the technical basis for development of recommendations for updates to the NUREG-1465 Source Term for BWRs that will extend its applicability to accidents involving high burnup (HBU) cores. However, a secondary objective is to re-examine the fundamental characteristics of the prescription for fission product release to containment described by NUREG-1465. This secondary objective is motivated by an interest to understand the extent to which research into the release and behaviors of radionuclides under accident conditions has altered best-estimate calculations of the integral response of BWRs to severe core damage sequences and the resulting radiological source terms to containment. This report, therefore, documents specific results of fission product source term analyses that will form the basis for the HBU supplement to NUREG-1465. However, commentary is also provided on observed differences between the composite results of the source term calculations performed here and those reflected NUREG-1465 itself.

  12. Advanced Corrosion-Resistant Zr Alloys for High Burnup and Generation IV Application

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. H.; Park, S. Y.; Lee, M. H.; Choi, B. K.; Baek, J. H.; Park, J. Y.; Kim, J. H.; Kim, H. G.; Jung, Y. H.; Bang, B. G

    2006-08-15

    The systematic study was performed to develop the advanced corrosion-resistant Zr alloys for high burnup and Gen IV application. The corrosion behavior was significantly changed with the alloy composition and the corrosion environment. In general, the model alloys with a higher alloying elements showed a higher corrosion resistance. Among the model alloys tested in this study, Zr-10Cr-0.2Fe showed the best corrosion resistance regardless of the corrosion condition. The oxide on the higher corrosion-resistant alloy such as Zr-1.0Cr-0.2Fe consisted of mainly columnar grains, and it have a higher tetragonal phase stability. In comparison with other alloys being considered for the SCWR, the Zr alloys showed a lower corrosion rate than ferritic-martensitic steels. The results of this study imply that, at least from a corrosion standpoint, Zr alloys deserve consideration as potential cladding or structural materials in supercritical water cooled reactors.

  13. Triton burnup study using scintillating fiber detector on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Harano, Hideki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1997-09-01

    The DT fusion reactor cannot be realized without knowing how the fusion-produced 3.5 MeV {alpha} particles behave. The {alpha} particles` behavior can be simulated using the 1 MeV triton. To investigate the 1 MeV triton`s behavior, a new type of directional 14 MeV neutron detector, scintillating fiber (Sci-Fi) detector has been developed and installed on JT-60U in the cooperation with LANL as part of a US-Japan collaboration. The most remarkable feature of the Sci-Fi detector is that the plastic scintillating fibers are employed for the neutron sensor head. The Sci-Fi detector measures and extracts the DT neutrons from the fusion radiation field in high time resolution (10 ms) and wide dynamic range (3 decades). Triton burnup analysis code TBURN has been made in order to analyze the time evolution of DT neutron emission rate obtained by the Sci-Fi detector. The TBURN calculations reproduced the measurements fairly well, and the validity of the calculation model that the slowing down of the 1 MeV triton was classical was confirmed. The Sci-Fi detector`s directionality indicated the tendency that the DT neutron emission profile became more and more peaked with the time progress. In this study, in order to examine the effect of the toroidal field ripple on the triton burnup, R{sub p}-scan and n{sub e}-scan experiments have been performed. The R{sub p}-scan experiment indicates that the triton`s transport was increased as the ripple amplitude over the triton became larger. In the n{sub e}-scan experiment, the DT neutron emission showed the characteristic changes after the gas puffing injection. It was theoretically confirmed that the gas puffing was effective for the collisionality scan. (J.P.N.) 127 refs.

  14. Neutron transport-burnup code MCORGS and its application in fusion fission hybrid blanket conceptual research

    Science.gov (United States)

    Shi, Xue-Ming; Peng, Xian-Jue

    2016-09-01

    Fusion science and technology has made progress in the last decades. However, commercialization of fusion reactors still faces challenges relating to higher fusion energy gain, irradiation-resistant material, and tritium self-sufficiency. Fusion Fission Hybrid Reactors (FFHR) can be introduced to accelerate the early application of fusion energy. Traditionally, FFHRs have been classified as either breeders or transmuters. Both need partition of plutonium from spent fuel, which will pose nuclear proliferation risks. A conceptual design of a Fusion Fission Hybrid Reactor for Energy (FFHR-E), which can make full use of natural uranium with lower nuclear proliferation risk, is presented. The fusion core parameters are similar to those of the International Thermonuclear Experimental Reactor. An alloy of natural uranium and zirconium is adopted in the fission blanket, which is cooled by light water. In order to model blanket burnup problems, a linkage code MCORGS, which couples MCNP4B and ORIGEN-S, is developed and validated through several typical benchmarks. The average blanket energy Multiplication and Tritium Breeding Ratio can be maintained at 10 and 1.15 respectively over tens of years of continuous irradiation. If simple reprocessing without separation of plutonium from uranium is adopted every few years, FFHR-E can achieve better neutronic performance. MCORGS has also been used to analyze the ultra-deep burnup model of Laser Inertial Confinement Fusion Fission Energy (LIFE) from LLNL, and a new blanket design that uses Pb instead of Be as the neutron multiplier is proposed. In addition, MCORGS has been used to simulate the fluid transmuter model of the In-Zinerater from Sandia. A brief comparison of LIFE, In-Zinerater, and FFHR-E will be given.

  15. The impact of interface bonding efficiency on high-burnup spent nuclear fuel dynamic performance

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Hao, E-mail: jiangh@ornl.gov; Wang, Jy-An John; Wang, Hong

    2016-12-01

    Highlights: • To investigate the impact of interfacial bonding efficiency at pellet-pellet and pellet-clad interfaces of high-burnup (HBU) spent nuclear fuel (SNF) on its dynamic performance. • Flexural rigidity, EI = M/κ, estimated from FEA results were benchmarked with SNF dynamic experimental results, and used to evaluate interface bonding efficiency. • Interface bonding efficiency can significantly dictate the SNF system rigidity and the associated dynamic performance. • With consideration of interface bonding efficiency and fuel cracking, HBU SNF fuel property was estimated with SNF static and dynamic experimental data. - Abstract: Finite element analysis (FEA) was used to investigate the impact of interfacial bonding efficiency at pellet-pellet and pellet-clad interfaces of high-burnup (HBU) spent nuclear fuel (SNF) on system dynamic performance. Bending moments M were applied to FEA model to evaluate the system responses. From bending curvature, κ, flexural rigidity EI can be estimated as EI = M/κ. The FEA simulation results were benchmarked with experimental results from cyclic integrated reversal bending fatigue test (CIRFT) of HBR fuel rods. The consequence of interface debonding between fuel pellets and cladding is a redistribution of the loads carried by the fuel pellets to the clad, which results in a reduction in composite rod system flexural rigidity. Therefore, the interface bonding efficiency at the pellet-pellet and pellet-clad interfaces can significantly dictate the SNF system dynamic performance. With the consideration of interface bonding efficiency, the HBU SNF fuel property was estimated with CIRFT test data.

  16. 10 CFR 51.31 - Determinations based on environmental assessment.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Determinations based on environmental assessment. 51.31 Section 51.31 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) ENVIRONMENTAL PROTECTION REGULATIONS FOR... appropriate NRC staff director will determine whether to prepare an environmental impact statement or a...

  17. A new colour constancy algorithm based on automatic determination ...

    Indian Academy of Sciences (India)

    In this article, we propose a neural network-based algorithm that aims to automatically determine the best value of gray framework parameters for each image. It is a multi-level approach that estimates the optimal values for the gray framework parameters based on relevant features extracted from the input image.

  18. THE INVESTIGATION OF BURNUP CHARACTERISTICS USING THE SERPENT MONTE CARLO CODE FOR A SODIUM COOLED FAST REACTOR

    Directory of Open Access Journals (Sweden)

    MEHMET E. KORKMAZ

    2014-06-01

    Full Text Available In this research, we investigated the burnup characteristics and the conversion of fertile 232Th into fissile 233U in the core of a Sodium-Cooled Fast Reactor (SFR. The SFR fuel assemblies were designed for burning 232Th fuel (fuel pin 1 and 233U fuel (fuel pin 2 and include mixed minor actinide compositions. Monte Carlo simulations were performed using Serpent Code1.1.19 to compare with CRAM (Chebyshev Rational Approximation Method and TTA (Transmutation Trajectory Analysis method in the burnup calculation mode. The total heating power generated in the system was assumed to be 2000 MWth. During the reactor operation period of 600 days, the effective multiplication factor (keff was between 0.964 and 0.954 and peaking factor is 1.88867.

  19. Analysis of the behavior under irradiation of high burnup nuclear fuels with the computer programs FRAPCON and FRAPTRAN

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Regis; Silva, Antonio Teixeira e, E-mail: teixeira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    The objective of this paper is to verify the validity and accuracy of the results provided by computer programs FRAPCON-3.4a and FRAPTRAN-1.4, used in the simulation process of the irradiation behavior of Pressurized Water Reactors (PWR) fuel rods, in steady-state and transient operational conditions at high burnup. To achieve this goal, the results provided by these computer simulations are compared with experimental data available in the database FUMEX III. Through the results, it was found that the computer programs used have a good ability to predict the operational behavior of PWR fuel rods in high burnup steady-state conditions and under the influence of Reactivity Initiated Accident (RIA). (author)

  20. Simulation of Low-Enriched Uranium (LEU) Burnup in Russian VVER Reactors with the HELIOS Code Package

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, B.D.; Kravchenko, J.; Lazarenko, A.; Pavlovitchev, A.; Sidorenko, V.; Chetverikov, A.

    2000-03-01

    The HELIOS reactor-physics computer program system was used to simulate the burnup of UO{sub 2} fuel in three VVER reactors. The manner in which HELIOS was used in these simulations is described. Predictions of concentrations for actinides up to {sup 244}Cm and for isotopes of neodymium were compared with laboratory-measured values. Reasonable agreement between calculated and measured values was seen for experimental samples from a fuel rod in the interior of an assembly.

  1. In Comparative Analysis for Fuel Burnup of Fuel Assembly Designs for the 300 kW Small Medical Reactor

    Science.gov (United States)

    Sambuu, Odmaa; Nanzad, Norov

    2009-03-01

    A 300 kW small medical reactor was designed to be used for boron neutron capture therapy (BNCT) at KAIST in 1996 [1]. In this paper, analysis for the core life cycle of the original design of the BNCT facility and modifications of the fuel assembly configuration and enrichment to get a proper life cycle were performed and a criticality, neutron flux distribution and fuel burnup calculations were carried out.

  2. OECD/NEA burnup credit criticality benchmarks phase IIIA: Criticality calculations of BWR spent fuel assemblies in storage and transport

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, Hiroshi; Naito, Yoshitaka [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ando, Yoshihira [Toshiba Corp., Kawasaki, Kanagawa (Japan)

    2000-09-01

    The report describes the final results of Phase IIIA Benchmarks conducted by the Burnup Credit Criticality Calculation Working Group under the auspices of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD/NEA). The benchmarks are intended to confirm the predictive capability of the current computer code and data library combinations for the neutron multiplication factor (k{sub eff}) of a layer of irradiated BWR fuel assembly array model. In total 22 benchmark problems are proposed for calculations of k{sub eff}. The effects of following parameters are investigated: cooling time, inclusion/exclusion of FP nuclides and axial burnup profile, and inclusion of axial profile of void fraction or constant void fractions during burnup. Axial profiles of fractional fission rates are further requested for five cases out of the 22 problems. Twenty-one sets of results are presented, contributed by 17 institutes from 9 countries. The relative dispersion of k{sub eff} values calculated by the participants from the mean value is almost within the band of {+-}1%{delta}k/k. The deviations from the averaged calculated fission rate profiles are found to be within {+-}5% for most cases. (author)

  3. Determinants of diarrhoeal diseases: a community based study in ...

    African Journals Online (AJOL)

    Determinants of diarrhoeal diseases: a community based study in urban south western Ethiopia. ... acute respiratory infecions (ARI) in the previous two weeks were found to be significantly associated with occurrence of diarrhoeal disease; however, only ARI and well water were retained in the logistic regression analysis.

  4. Determinants of Inequality in Cameroon: A Regression-Based ...

    African Journals Online (AJOL)

    This paper applies the regression-based inequality decomposition approach to explore determinants of income inequality in Cameroon using the 2007 Cameroon household consumption survey. The contribution of each source to measured income inequality is the sum of its weighted marginal contributions in all possible ...

  5. Dimethylglyoxime based ion-imprinted polymer for the determination ...

    African Journals Online (AJOL)

    Dimethylglyoxime based ion-imprinted polymer for the determination of Ni(II) ions from aqueous samples. ... The accuracy of the method was validated by analysing a custom solution of certified reference material (SEP-3) and the concentration of Ni(II) obtained was in close agreement with the certified one. The Ni(II)-DMG ...

  6. Determining Evidence-Based Practices in Special Education

    Science.gov (United States)

    Cook, Bryan G.; Tankersley, Melody; Landrum, Timothy J.

    2009-01-01

    Determining evidence-based practices is a complicated enterprise that requires analyzing the methodological quality and magnitude of the available research supporting specific practices. This article reviews criteria and procedures for identifying what works in the fields of clinical psychology, school psychology, and general education; and it…

  7. TEM Characterization of High Burn-up Microstructure of U-7Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jian Gan; Brandon Miller; Dennis Keiser; Adam Robinson; James Madden; Pavel Medvedev; Daniel Wachs

    2014-04-01

    As an essential part of global nuclear non-proliferation effort, the RERTR program is developing low enriched U-Mo fuels (< 20% U-235) for use in research and test reactors that currently employ highly enriched uranium fuels. One type of fuel being developed is a dispersion fuel plate comprised of U-7Mo particles dispersed in Al alloy matrix. Recent TEM characterizations of the ATR irradiated U-7Mo dispersion fuel plates include the samples with a local fission densities of 4.5, 5.2, 5.6 and 6.3 E+21 fissions/cm3 and irradiation temperatures of 101-136?C. The development of the irradiated microstructure of the U-7Mo fuel particles consists of fission gas bubble superlattice, large gas bubbles, solid fission product precipitates and their association to the large gas bubbles, grain subdivision to tens or hundreds of nanometer size, collapse of bubble superlattice, and amorphisation. This presentation will describe the observed microstructures specifically focusing on the U-7Mo fuel particles. The impact of the observed microstructure on the fuel performance and the comparison of the relevant features with that of the high burn-up UO2 fuels will be discussed.

  8. SEM Characterization of the High Burn-up Microstructure of U-7Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dennis D. Keiser, Jr.; Jan-Fong Jue; Jian Gan; Brandon Miller; Adam Robinson; Pavel Medvedev; James Madden; Dan Wachs; M. Teague

    2014-04-01

    During irradiation, the microstructure of U-7Mo evolves until at a fission density near 5x1021 f/cm3 a high-burnup microstructure exists that is very different than what was observed at lower fission densities. This microstructure is dominated by randomly distributed, relatively large, homogeneous fission gas bubbles. The bubble superlattice has collapsed in many microstructural regions, and the fuel grain sizes, in many areas, become sub-micron in diameter with both amorphous fuel and crystalline fuel present. Solid fission product precipitates can be found inside the fission gas bubbles. To generate more information about the characteristics of the high-fission density microstructure, three samples irradiated in the RERTR-7 experiment have been characterized using a scanning electron microscope equipped with a focused ion beam. The FIB was used to generate samples for SEM imaging and to perform 3D reconstruction of the microstructure, which can be used to look for evidence of possible fission gas bubble interlinkage.

  9. Determination of trace patulin in apple-based food matrices.

    Science.gov (United States)

    Li, Xianjiang; Li, Hongmei; Li, Xiaomin; Zhang, Qinghe

    2017-10-15

    Patulin is a toxic metabolite of a number of fungi; its toxicity is serious and its contamination in food is a worldwide problem, especially in apple-based food. Effective control of patulin contamination strongly depends on reliable analytical methods. In this review, various analytical methods, especially those that have appeared in the last ten years, are summarized, including the highly reproducible chromatography and mass-spectrometry-based methods, highly selective sensor-based methods and indirect quantitative PCR methods. This review also summarizes the promising features of novel materials in sample preparation for patulin determination. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Adaptive Noise Parameter Determination Based on a Particle Filter Algorithm

    Directory of Open Access Journals (Sweden)

    Hyun-Tae Cho

    2016-01-01

    Full Text Available Due to the growing number of vehicles using the national road networks that link major urban centers, traffic noise is becoming a major issue in relation to the transportation system. Thus, it is important to determine noise model parameters to predict road traffic noise levels as part of an environmental assessment, according to traffic volume and pavement surface type. To determine the parameters of a noise prediction model, statistical pass-by and close proximity tests are required. This paper provides a parameter determination procedure for noise prediction models through an adaptive particle filter (PF algorithm, based on using a weigh-in-motion system, which obtains vehicle velocities and types, as well as step-up microphones, which measure the combined noises emitted by various vehicle types. Finally, an evaluation of the adaptive noise parameter determination algorithm was carried out to assess the agreement between predictions and measurements.

  11. Thermal property change of MOX and UO{sub 2} irradiated up to high burnup of 74 GWd/t

    Energy Technology Data Exchange (ETDEWEB)

    Nakae, Nobuo, E-mail: nakae-nobuo@jnes.go.jp [Japan Nuclear Energy Safety Organization (JNES), Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Akiyama, Hidetoshi; Miura, Hiromichi; Baba, Toshikazu; Kamimura, Katsuichiro [Japan Nuclear Energy Safety Organization (JNES), Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Kurematsu, Shigeru; Kosaka, Yuji [Nuclear Development Corporation (NDC), 622-12, Funaishikawa, Tokai-mura, Ibaraki 319-1111 (Japan); Yoshino, Aya; Kitagawa, Takaaki [Mitsubishi Nuclear Fuel Co., LTD. (MNF), 12-1, Yurakucho 1-Chome, Chiyoda-ku, Tokyo 100-0006 (Japan)

    2013-09-15

    Thermal property is important because it controls fuel behavior under irradiation. The thermal property change at high burnup of more than 70 GWd/t is examined. Two kinds of MOX fuel rods, which were fabricated by MIMAS and SBR methods, and one referenced UO{sub 2} fuel rod were used in the experiment. These rods were taken from the pre-irradiated rods (IFA 609/626, of which irradiation test were carried out by Japanese PWR group) and re-fabricated and re-irradiated in HBWR as IFA 702 by JNES. The specification of fuel corresponds to that of 17 × 17 PWR type fuel and the axially averaged linear heat rates (LHR) of MOX rods are 25 kW/m (BOL of IFA 702) and 20 kW/m (EOL of IFA 702). The axial peak burnups achieved are about 74 GWd/t for both of MOX and UO{sub 2}. Centerline temperature and plenum gas pressure were measured in situ during irradiation. The measured centerline temperature is plotted against LHR at the position where thermocouples are fixed. The slopes of MOX are corresponded to each other, but that of UO{sub 2} is higher than those of MOX. This implies that the thermal conductivity of MOX is higher than that of UO{sub 2} at high burnup under the condition that the pellet–cladding gap is closed during irradiation. Gap closure is confirmed by the metallography of the postirradiation examinations. It is understood that thermal conductivity of MOX is lower than that of UO{sub 2} before irradiation since phonon scattering with plutonium in MOX becomes remarkable. A phonon scattering with plutonium decreases in MOX when burnup proceeds. Thus, thermal conductivity of MOX becomes close to that of UO{sub 2}. A reverse phenomenon is observed at high burnup region. The phonon scattering with fission products such as Nd and Zr causes a degradation of thermal conductivity of burnt fuel. It might be speculated that this scattering effect causes the phenomenon and the mechanism is discussed here.

  12. Automated Dimension Determination for NMF-based Incremental Collaborative Filtering

    Directory of Open Access Journals (Sweden)

    Xiwei Wang

    2015-12-01

    Full Text Available The nonnegative matrix factorization (NMF based collaborative filtering t e chniques h a ve a c hieved great success in product recommendations. It is well known that in NMF, the dimensions of the factor matrices have to be determined in advance. Moreover, data is growing fast; thus in some cases, the dimensions need to be changed to reduce the approximation error. The recommender systems should be capable of updating new data in a timely manner without sacrificing the prediction accuracy. In this paper, we propose an NMF based data update approach with automated dimension determination for collaborative filtering purposes. The approach can determine the dimensions of the factor matrices and update them automatically. It exploits the nearest neighborhood based clustering algorithm to cluster users and items according to their auxiliary information, and uses the clusters as the constraints in NMF. The dimensions of the factor matrices are associated with the cluster quantities. When new data becomes available, the incremental clustering algorithm determines whether to increase the number of clusters or merge the existing clusters. Experiments on three different datasets (MovieLens, Sushi, and LibimSeTi were conducted to examine the proposed approach. The results show that our approach can update the data quickly and provide encouraging prediction accuracy.

  13. Examining the Determinants of Mobile Location-based Services' Continuance

    DEFF Research Database (Denmark)

    Lehrer, Christiane; Constantiou, Ioanna; Hess, Thomas

    2011-01-01

    true for consumer-oriented services, which rely on advertising, or subscription-based revenue models. In this paper, we investigate the determinants of location-based services (LBS) continuance as a relevant case study for the examination of IS continuance generally. A research model is developed...... and empirically tested through a survey of a representative sample in Germany. The proposed model builds on and extends the Limayem et al. model of IS continuance. Our analysis highlights the importance of habit and emotion in LBS continuance. The results indicate that habit has a stronger predictive power than...

  14. DETERMINING STAND PARAMETERS FROM UAS-BASED POINT CLOUDS

    Directory of Open Access Journals (Sweden)

    V. Yilmaz

    2016-06-01

    Full Text Available In Turkey, forest management plans are produced by terrestrial surveying techniques for 10 or 20 year periods, which can be considered quite long to maintain the sustainability of forests. For a successful forest management plan, it is necessary to collect accurate information about the stand parameters and store them in dynamic and robust databases. The position, number, height and closure of trees are among the most important stand parameters required for a forest management plan. Determining the position of each single tree is challenging in such an area consisting of too many interlocking trees. Hence, in this study, an object-based tree detection methodology has been developed in MATLAB programming language to determine the position of each tree top in a highly closed area. The developed algorithm uses the Canopy Height Model (CHM, which is computed from the Digital Terrain Model (DTM and Digital Surface Model (DSM generated by using the point cloud extracted from the images taken from a UAS (Unmanned Aerial System. The heights of trees have been determined by using the CHM. The closure of the trees has been determined with the written MATLAB script. The results show that the developed tree detection methodology detected more than 70% of the trees successfully. It can also be concluded that the stand parameters may be determined by using the UAS-based point clouds depending on the characteristics of the study area. In addition, determination of the stand parameters by using point clouds reduces the time needed to produce forest management plans.

  15. Temperature and Burnup Correlated FCCI in U-10Zr Metallic Fuel

    Energy Technology Data Exchange (ETDEWEB)

    William J. Carmack

    2012-05-01

    Metallic fuels are proposed for use in advanced sodium cooled fast reactors. The experience basis for metallic fuels is extensive and includes development and qualification of fuels for the Experimental Breeder Reactor I, the Experimental Breeder Reactor II, FERMI-I, and the Fast Flux Test Facility (FFTF) reactors. Metallic fuels provide a number of advantages over other fuel types in terms of fabricability, performance, recyclability, and safety. Key to the performance of all nuclear fuel systems is the resistance to “breach” and subsequent release of fission products and fuel constituents to the primary coolant system of the nuclear power plant. In metallic fuel, the experience is that significant fuel-cladding chemical (FCCI) interaction occurs and becomes prevalent at high power-high temperature operation and ultimately leads to fuel pin breach and failure. Empirical relationships for metallic fuel pin failure have been developed from a large body of in-pile and out of pile research, development, and experimentation. It has been found that significant in-pile acceleration of the FCCI rate is experienced over similar condition out-of-pile experiments. The study of FCCI in metallic fuels has led to the quantification of in-pile failure rates to establish an empirical time and temperature dependent failure limit for fuel elements. Up until now the understanding of FCCI layer formation has been limited to data generated in EBR-II experiments. This dissertation provides new FCCI data extracted from the MFF-series of metallic fuel irradiations performed in the FFTF. These fuel assemblies contain valuable information on the formation of FCCI in metallic fuels at a variety of temperature and burnup conditions and in fuel with axial fuel height three times longer than EBR-II experiments. The longer fuel column in the FFTF and the fuel pins examined have significantly different flux, power, temperature, and FCCI profiles than that found in similar tests conducted in

  16. FY14 Status Report: CIRFT Testing Results on High Burnup UNF

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Wang, Hong [ORNL; Jiang, Hao [ORNL

    2014-09-01

    The objective of this project is to perform a systematic study of SNF/UNF (spent nuclear fuel/or used nuclear fuel) integrity under simulated transportation environments by using hot cell testing technology developed recently at Oak Ridge National Laboratory (ORNL), CIRFT (Cyclic Integrated Reversible-Bending Fatigue Tester). Under Nuclear Regulatory Commission (NRC) sponsorship, ORNL completed four benchmarking tests, four static tests, and twelve dynamic or cycle tests on H. B. Robinson (HBR) high burn-up (HBU) fuel. With support from the US Department of Energy and the NRC, CIRFT testing has been continued. The CIRFT testing was conducted on three HBR rods (R3, R4, and R5), with two specimens failed and one specimen un-failed. The total number of cycles in the test of un-failed specimens went over 2.23 107; the test was stopped as because the specimen did not show any sign of failure. The data analysis on all the HBR SNF rods demonstrated that it is necessary to characterize the fatigue life of used fuel rods in terms of both the curvature amplitude and the maximum of absolute of curvature extremes. The latter is significant because the maxima of extremes signify the maximum of tensile stress of the outer fiber of the bending rod. So far, a large variety of hydrogen contents has been covered in the CIRFT testing on HBR rods. It has been shown that the load amplitude is the dominant factor that controls the lifetime of bending rods, but the hydrogen content also has an important effect on the lifetime attained, according to the load range tested.

  17. The effect of dissolved hydrogen on the dissolution of {sup 233}U doped UO{sub 2}(s) high burn-up spent fuel and MOX fuel

    Energy Technology Data Exchange (ETDEWEB)

    Carbol, P. [Inst. for Transuranium Elements, Karlsruhe (Germany); Spahiu, K. (ed.) [and others

    2005-03-01

    In this report the results of the experimental work carried out in a large EU-research project (SFS, 2001-2004) on spent fuel stability in the presence of various amounts of near field hydrogen are presented. Studies of the dissolution of {sup 233}U doped UO{sub 2}(s) simulating 'old' spent fuel were carried out as static leaching tests, autoclave tests with various hydrogen concentrations and electrochemical tests. The results of the leaching behaviour of a high burn-up spent fuel pellet in 5 M NaCl solutions in the presence of 3.2 bar H{sub 2} pressure and of MOX fuel in dilute synthetic groundwater under 53 bar H{sub 2} pressure are also presented. In all the experimental studies carried out in this project, a considerable effect of hydrogen in the dissolution rates of radioactive materials was observed. The experimental results obtained in this project with a-doped UO{sub 2}, high burn-up spent fuel and MOX fuel together with literature data give a reliable background to use fractional alteration/dissolution rates for spent fuel of the order of 10{sup -6}/yr - 10{sup -8}/yr with a recommended value of 4x10{sup -7}/yr for dissolved hydrogen concentrations above 10{sup -3} M and Fe(II) concentrations typical for European repository concepts. Finally, based on a review of the experimental data and available literature data, potential mechanisms of the hydrogen effect are also discussed. The work reported in this document was performed as part of the Project SFS of the European Commission 5th Framework Programme under contract no FIKW-CT-2001-20192 SFS. It represents the deliverable D10 of the experimental work package 'Key experiments using a-doped UO{sub 2} and real spent fuel', coordinated by SKB with the participation of ITU, FZK-INE, ENRESA, CIEMAT, ARMINES-SUBATECH and SKB.

  18. Reactivity loss validation of high burn-up PWR fuels with pile-oscillation experiments in MINERVE

    Energy Technology Data Exchange (ETDEWEB)

    Leconte, P.; Vaglio-Gaudard, C.; Eschbach, R.; Di-Salvo, J.; Antony, M.; Pepino, A. [CEA, DEN, DER, Cadarache, F-13108 Saint-Paul-Lez-Durance (France)

    2012-07-01

    The ALIX experimental program relies on the experimental validation of the spent fuel inventory, by chemical analysis of samples irradiated in a PWR between 5 and 7 cycles, and also on the experimental validation of the spent fuel reactivity loss with bum-up, obtained by pile-oscillation measurements in the MINERVE reactor. These latter experiments provide an overall validation of both the fuel inventory and of the nuclear data responsible for the reactivity loss. This program offers also unique experimental data for fuels with a burn-up reaching 85 GWd/t, as spent fuels in French PWRs never exceeds 70 GWd/t up to now. The analysis of these experiments is done in two steps with the APOLLO2/SHEM-MOC/CEA2005v4 package. In the first one, the fuel inventory of each sample is obtained by assembly calculations. The calculation route consists in the self-shielding of cross sections on the 281 energy group SHEM mesh, followed by the flux calculation by the Method Of Characteristics in a 2D-exact heterogeneous geometry of the assembly, and finally a depletion calculation by an iterative resolution of the Bateman equations. In the second step, the fuel inventory is used in the analysis of pile-oscillation experiments in which the reactivity of the ALIX spent fuel samples is compared to the reactivity of fresh fuel samples. The comparison between Experiment and Calculation shows satisfactory results with the JEFF3.1.1 library which predicts the reactivity loss within 2% for burn-up of {approx}75 GWd/t and within 4% for burn-up of {approx}85 GWd/t. (authors)

  19. Effect of fuel burnup and cross sections on modular HTGR (High-Temperature Gas-cooled Reactor) reactivity coefficients

    Science.gov (United States)

    Lefler, W.; Baxter, A.; Mathews, D.

    1987-12-01

    The temperature dependence of the reactivity coefficient in a prismatic block Modular High-Temperature Gas-Cooled Reactor (MHTGR) design is examined and found to be large and negative. Temperature coefficient results obtained with the ENDF/B-V data library were almost the same as results obtained with the earlier versions of the ENDF/B data library usually used at GA Technologies Inc., in spite of a significant eigenvalue increase with the ENDF/B-V data. The effects of fuel burnup and arbitrarily assumed cross section variations were examined and tabulated.

  20. Accident source terms for pressurized water reactors with high-burnup cores calculated using MELCOR 1.8.5.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Ashbaugh, Scott G.; Leonard, Mark Thomas; Longmire, Pamela

    2010-04-01

    In this study, risk-significant pressurized-water reactor severe accident sequences are examined using MELCOR 1.8.5 to explore the range of fission product releases to the reactor containment building. Advances in the understanding of fission product release and transport behavior and severe accident progression are used to render best estimate analyses of selected accident sequences. Particular emphasis is placed on estimating the effects of high fuel burnup in contrast with low burnup on fission product releases to the containment. Supporting this emphasis, recent data available on fission product release from high-burnup (HBU) fuel from the French VERCOR project are used in this study. The results of these analyses are treated as samples from a population of accident sequences in order to employ approximate order statistics characterization of the results. These trends and tendencies are then compared to the NUREG-1465 alternative source term prescription used today for regulatory applications. In general, greater differences are observed between the state-of-the-art calculations for either HBU or low-burnup (LBU) fuel and the NUREG-1465 containment release fractions than exist between HBU and LBU release fractions. Current analyses suggest that retention of fission products within the vessel and the reactor coolant system (RCS) are greater than contemplated in the NUREG-1465 prescription, and that, overall, release fractions to the containment are therefore lower across the board in the present analyses than suggested in NUREG-1465. The decreased volatility of Cs2MoO4 compared to CsI or CsOH increases the predicted RCS retention of cesium, and as a result, cesium and iodine do not follow identical behaviors with respect to distribution among vessel, RCS, and containment. With respect to the regulatory alternative source term, greater differences are observed between the NUREG-1465 prescription and both HBU and LBU predictions than exist between HBU and LBU

  1. A rights-based approach to accessing health determinants.

    Science.gov (United States)

    Perkins, Fran

    2009-03-01

    This commentary summarizes the experience and learnings from a site visit in May 2008 to a drop-in centre for vulnerable women in downtown Cairo run by El-Shehab Institution for Comprehensive Development, which provides street outreach for the prevention of Sexually Transmitted Infection (STI). The Centre successfully provides services and support for women, many of who are displaced or refugees and are from the most marginalized areas in Cairo. Through a rights-based approach to the work, the Centre helps people living in the slums fight and win the right to access clean water, sewerage and electrical power in their communities. An individual-based approach to human rights is also used. In the last year El-Shehab have helped 67 women go to court and win their marriage rights from husbands who have abandoned them. Their approach is an example of a successful way to achieve access to basic health determinants.

  2. Textile-based sampling for potentiometric determination of ions.

    Science.gov (United States)

    Lisak, Grzegorz; Arnebrant, Thomas; Ruzgas, Tautgirdas; Bobacka, Johan

    2015-06-02

    Potentiometric sensing utilizing textile-based micro-volume sampling was applied and evaluated for the determination of clinically (Na(+), K(+), Cl(-)) and environmentally (Cd(2+), Pb(2+) and pH) relevant analytes. In this technological design, calibration solutions and samples were absorbed into textiles while the potentiometric cells (ion-selective electrodes and reference electrode) were pressed against the textile. Once the liquid, by wicking action, reached the place where the potentiometric cell was pressed onto the textile, hence closing the electric circuit, the potentiometric response was obtained. Cotton, polyamide, polyester and their blends with elastane were applied for micro-volume sampling. The textiles were found to influence the determination of pH in environmental samples with pH close to neutral and Pb(2+) at low analyte concentrations. On the other hand, textile-based micro-volume sampling was successfully applied in measurements of Na(+) using solid-contact sodium-selective electrodes utilizing all the investigated textiles for sampling. It was found that in order to extend the application of textile-based sampling toward environmental analysis of ions it will be necessary to tailor the physio-chemical properties of the textile materials. In general, textile-based sampling opens new possibilities for direct chemical analysis of small-volume samples and provide a simple and low-cost method to screen various textiles for their effects on samples to identify which textiles are the most suitable for on-body sensing. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Determination of the human spine curve based on laser triangulation.

    Science.gov (United States)

    Poredoš, Primož; Čelan, Dušan; Možina, Janez; Jezeršek, Matija

    2015-02-05

    The main objective of the present method was to automatically obtain a spatial curve of the thoracic and lumbar spine based on a 3D shape measurement of a human torso with developed scoliosis. Manual determination of the spine curve, which was based on palpation of the thoracic and lumbar spinous processes, was found to be an appropriate way to validate the method. Therefore a new, noninvasive, optical 3D method for human torso evaluation in medical practice is introduced. Twenty-four patients with confirmed clinical diagnosis of scoliosis were scanned using a specially developed 3D laser profilometer. The measuring principle of the system is based on laser triangulation with one-laser-plane illumination. The measurement took approximately 10 seconds at 700 mm of the longitudinal translation along the back. The single point measurement accuracy was 0.1 mm. Computer analysis of the measured surface returned two 3D curves. The first curve was determined by manual marking (manual curve), and the second was determined by detecting surface curvature extremes (automatic curve). The manual and automatic curve comparison was given as the root mean square deviation (RMSD) for each patient. The intra-operator study involved assessing 20 successive measurements of the same person, and the inter-operator study involved assessing measurements from 8 operators. The results obtained for the 24 patients showed that the typical RMSD between the manual and automatic curve was 5.0 mm in the frontal plane and 1.0 mm in the sagittal plane, which is a good result compared with palpatory accuracy (9.8 mm). The intra-operator repeatability of the presented method in the frontal and sagittal planes was 0.45 mm and 0.06 mm, respectively. The inter-operator repeatability assessment shows that that the presented method is invariant to the operator of the computer program with the presented method. The main novelty of the presented paper is the development of a new, non-contact method

  4. Ultrasound-based protein determination in maize seeds.

    Science.gov (United States)

    Drochioiu, Gabi; Ciobanu, Catalina Ionica; Bancila, Sabina; Ion, Laura; Petre, Brindusa Alina; Andries, Claudia; Gradinaru, Robert Vasile; Murariu, Manuela

    2016-03-01

    The need for a simple and accurate method for protein estimation in alcoholic extracts led to the reexamination of the optimum conditions of a colorimetric assay based on the biuret reaction. Sonication time and the other experimental parameters were optimized after kinetics study on the extraction of either zein or total proteins. Zein extraction and purity were investigated by (1)H and (13)C NMR spectroscopy, SDS-PAGE electrophoresis, and UV-visible spectrophotometry (UV-vis). A zein assay was proposed, which involves the reaction of copper ions in copper phosphate powder with zein extracted in ethanolic solutions under strong alkaline environment. Furthermore, we extended this procedure to determine total proteins in maize samples simultaneously with their ultrasonic-assisted (US) extraction with an alkaline-alcoholic solution. Proteins in both types of extracts were well characterized by UV-vis spectroscopy. However, the 545 nm absorbance of the violet-colored supernatants which is proportional to the protein content was found to be the key parameter of the improved biuret-based protein assay. Comparison of values obtained by this procedure and by Micro-Kjeldahl method was in excellent agreement. A scaled-down procedure agreed well with the standard procedure. Enhanced accuracy and repeatability was found in protein determination in maize using the modified biuret method. The optimization of reagent concentrations and incubation times were studied as well. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Instant release of fission products in leaching experiments with high burn-up nuclear fuels in the framework of the Euratom project FIRST- Nuclides

    Science.gov (United States)

    Lemmens, K.; González-Robles, E.; Kienzler, B.; Curti, E.; Serrano-Purroy, D.; Sureda, R.; Martínez-Torrents, A.; Roth, O.; Slonszki, E.; Mennecart, T.; Günther-Leopold, I.; Hózer, Z.

    2017-02-01

    The instant release of fission products from high burn-up UO2 fuels and one MOX fuel was investigated by means of leach tests. The samples covered PWR and BWR fuels at average rod burn-up in the range of 45-63 GWd/tHM and included clad fuel segments, fuel segments with opened cladding, fuel fragments and fuel powder. The tests were performed with sodium chloride - bicarbonate solutions under oxidizing conditions and, for one test, in reducing Ar/H2 atmosphere. The iodine and cesium release could be partially explained by the differences in sample preparation, leading to different sizes and properties of the exposed surface areas. Iodine and cesium releases tend to correlate with FGR and linear power rating, but the scatter of the data is significant. Although the gap between the fuel and the cladding was closed in some high burn-up samples, fissures still provide possible preferential transport pathways.

  6. High-Burnup-Structure (HBS): Model Development in MARMOT for HBS Formation and Stability Under Radiation and High Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bai, X. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, Y. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Biner, B. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    A detailed phase field model for the formation of High Burnup Structure (HBS) was developed and implemented in MARMOT. The model treats the HBS formation as an irradiation-induced recrystallization. The model takes into consideration the stored energy associated with dislocations formed under irradiation. The accumulation of radiation damage, hence, increases the system free energy and triggers recrystallization. The increase in the free energy due to the formation of new grain boundaries is offset by the reduction in the free energy by creating dislocation-free grains at the expense of the deformed grains. The model was first used to study the growth of recrystallized flat and circular grains. The model reults were shown to agree well with theorrtical predictions. The case of HBS formation in UO2 was then investigated. It was found that a threshold dislocation density of (or equivalently a threshold burn-up of 33-40 GWd/t) is required for HBS formation at 1200K, which is in good agrrement with theory and experiments. In future studies, the presence of gas bubbles and their effect on the formation and evolution of HBS will be considered.

  7. Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

    Science.gov (United States)

    Ternovykh, Mikhail; Tikhomirov, Georgy; Saldikov, Ivan; Gerasimov, Alexander

    2017-09-01

    Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

  8. Accident source terms for light-water nuclear power plants using high-burnup or MOX fuel.

    Energy Technology Data Exchange (ETDEWEB)

    Salay, Michael (U.S. Nuclear Regulatory Commission, Washington, D.C.); Gauntt, Randall O.; Lee, Richard Y. (U.S. Nuclear Regulatory Commission, Washington, D.C.); Powers, Dana Auburn; Leonard, Mark Thomas

    2011-01-01

    Representative accident source terms patterned after the NUREG-1465 Source Term have been developed for high burnup fuel in BWRs and PWRs and for MOX fuel in a PWR with an ice-condenser containment. These source terms have been derived using nonparametric order statistics to develop distributions for the timing of radionuclide release during four accident phases and for release fractions of nine chemical classes of radionuclides as calculated with the MELCOR 1.8.5 accident analysis computer code. The accident phases are those defined in the NUREG-1465 Source Term - gap release, in-vessel release, ex-vessel release, and late in-vessel release. Important differences among the accident source terms derived here and the NUREG-1465 Source Term are not attributable to either fuel burnup or use of MOX fuel. Rather, differences among the source terms are due predominantly to improved understanding of the physics of core meltdown accidents. Heat losses from the degrading reactor core prolong the process of in-vessel release of radionuclides. Improved understanding of the chemistries of tellurium and cesium under reactor accidents changes the predicted behavior characteristics of these radioactive elements relative to what was assumed in the derivation of the NUREG-1465 Source Term. An additional radionuclide chemical class has been defined to account for release of cesium as cesium molybdate which enhances molybdenum release relative to other metallic fission products.

  9. Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

    Directory of Open Access Journals (Sweden)

    Ternovykh Mikhail

    2017-01-01

    Full Text Available Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

  10. Shutdown-induced tensile stress in monolithic miniplates as a possible cause of plate pillowing at very high burnup

    Energy Technology Data Exchange (ETDEWEB)

    Medvedev, Pavel G [Idaho National Laboratory; Ozaltun, Hakan [Idaho National Laboratory; Robinson, Adam Brady [Idaho National Laboratory; Rabin, Barry H [Idaho National Laboratory

    2014-04-01

    Post-irradiation examination of Reduced Enrichment for Research and Test Reactors (RERTR)-12 miniplates showed that in-reactor pillowing occurred in at least 4 plates, rendering performance of these plates unacceptable. To address in-reactor failures, efforts are underway to define the mechanisms responsible for in-reactor pillowing, and to suggest improvements to the fuel plate design and operational conditions. To achieve these objectives, the mechanical response of monolithic fuel to fission and thermally-induced stresses was modeled using a commercial finite element analysis code. Calculations of stresses and deformations in monolithic miniplates during irradiation and after the shutdown revealed that the tensile stress generated in the fuel increased from 2 MPa to 100 MPa at shutdown. The increase in tensile stress at shutdown possibly explains in-reactor pillowing of several RERTR-12 miniplates irradiated to the peak local burnup of up to 1.11x1022 fissions/cm3 . This paper presents the modeling approach and calculation results, and compares results with post-irradiation examinations and mechanical testing of irradiated fuel. The implications for the safe use of the monolithic fuel in research reactors are discussed, including the influence of fuel burnup and power on the magnitude of the shutdown-induced tensile stress.

  11. Morphometric-based sexual determination of Bananaquits (Coereba flaveola)

    Science.gov (United States)

    Bibles, Brent D.; Boal, Clint W.

    2012-01-01

    The Bananaquit (Coereba flaveola) is a common passerine throughout the tropics and has been a convenient species for ecological studies. This species has sexually monomorphic plumage and cannot be reliably sexed unless in breeding condition. This is problematic for demographic and comparative studies, which are contingent upon accurately aging and sexing individuals. Although male Bananaquits are larger than females, there is overlap in both wing chord and mass. We used morphometric data collected over eight years to develop a predictive model based on logistic regression to assign adult Bananaquits to sex. Our model classified 96% of validation individuals to the correct sex. We suggest that this approach may enhance ecological studies of the species by facilitating correct sex determination independent of breeding status. We believe our modeling approach is applicable elsewhere but, because there may be geographical variation across the species distribution, models will need to be customized to local populations.

  12. Proposal for facial type determination based on anthropometry.

    Science.gov (United States)

    Ramires, Rossana Ribeiro; Ferreira, Léslie Piccolotto; Marchesan, Irene Queiroz; Cattoni, Débora Martins; Silva, Marta Assumpção de Andrada E

    2011-09-01

    To describe orofacial indexes and proportions in adults, according to facial type and gender, and to verify the possibility to establish a way of classifying face based on anthropometry. Participants were 105 leukoderm adults, 34 male (32.4%) and 71 female (67.6%), with ages between 20 and 40 years old, patients in a private orthodontic clinic in Belo Horizonte, Minas Gerais, Brazil. The findings from the cephalometric analysis contained in their orthodontic records were used for determination of facial type. Subjects were divided according to gender and facial type, and were submitted to anthropometric facial measures obtained directly through a caliper rule. These measures were compared to six variables: facial index, lower face index, upper face index, chin-face height proportion, chin height proportion, and mandibular height proportion. The average values obtained by the subjects divided into genders and facial types that presented significant differences were: facial index, lower face index, upper face index, and mandibular height proportion for males, and mandibular height proportion, for females. To predict facial types, the following parameters were considered significant: facial index, upper face index and mandibular height proportion for the dolichofacial type, for males; and mandibular height proportion for the dolichofacial and lower face index for the brachyfacial type, for females. Some indexes and orofacial proportions present variations according to facial types and genders. In general, the anthropometric variables in this study are not good predictors to determine facial types.

  13. Source distance determination based on the spherical harmonics

    Science.gov (United States)

    Koutny, Adam; Jiricek, Ondrej; Thomas, Jean-Hugh; Brothanek, Marek

    2017-02-01

    This paper deals with the processing of signals measured by a spherical microphone array, focusing on the utilization of near-field information of such an array. The processing, based on the spherical harmonics decomposition, is performed in order to investigate the radial-dependent spherical functions and extract their argument - distance to the source. Using the low-frequency approximation of these functions, the source distance is explicitly expressed. The source distance is also determined from the original equation (using no approximation) by comparing both sides of this equation. The applicability of both methods is first presented in the noise-less data simulation, then validated with data contaminated by the additive white noise of different signal-to-noise ratios. Finally, both methods are tested for real data measured by a rigid spherical microphone array of radius 0.15 m, consisting of 36 microphones for a point source represented by a small speaker. The possibility of determination of the source distance using low-order spherical harmonics is shown.

  14. Sound velocity determination in gel-based emulsions.

    Science.gov (United States)

    Ammann, Jean-Jacques; Galaz, Belfor

    2003-09-01

    Sound velocity is a main parameter in non destructive characterization, closely related to the elastic properties and to the microstructure of heterogeneous materials. The accurate determination of the sound velocity using pulse-echo technique relies on the ability to reduce pulse distortion and to measure specimen dimensions with a high precision. In the field of bio-mimetic materials and biological tissues, the nature of the specimen makes this last requirement highly difficult or inappropriate. The present work, using a through-transmission configuration, allows, in a stress free environment, to access the sound velocity in soft, low acoustic contrast materials without requiring the specimen dimensions. The specimen sound velocity is obtained from the echo time-of-flights through a Z-scan process providing the absolute medium sound velocity as reference. The technique uses an excitation burst at a frequency below the transducer resonance to ensure a significantly reduction in pulse distortions and improve signal-to-noise ratio. The accurate determination of the echo time-of-flight relies on a highly efficient cross-correlation/Hilbert transform signal processing. The method has been applied to gel-based emulsions of different microstructures considered as biomimetic phantoms, as well as to their constituents: pure gelatin and vegetable oil.

  15. A Porphyrin Based Potentiometric Sensor for Zn2+ Determination

    Directory of Open Access Journals (Sweden)

    H. Lang

    2003-07-01

    Full Text Available PVC based membranes of disodium salt of porphyrin 3,7,12,17-tetramethyl-8, 13-divinyl 2,18-porphine dipropionic acid (I as ionophore with sodium tetra phenyl borate (NaTPB as anion excluder and dibutyl phthalate (DBP, dioctyl phthalate (DOP, dibutyl butyl phosphonate (DBBP, tris(2- ethyl hexylphosphate (TEP, tri-n-butylphosphate (TBP and 1- chloronaphthalene (CN as plasticizing solvent mediators were prepared and constructed for determination of Zn(II. The PVC based membrane of (I with DBBP as plasticizer and having anion excluder, NaTPB in the ratio PVC: I: NaTPB: DBBP (150: 10: 2: 200 gave the best results in terms of working concentration range (1.3×10-5-1.0 ×10-1M with a Nernstian slope (30.0 mV/decade of activity. The useful pH range of the sensor is 3.0 –7.4, beyond which a drift in potential was observed. The response time of the sensor is 10s and the lifetime was about 2 months during which it could be used without any measurable divergence. It had good stability and reproducibility. The membrane worked satisfactorily in non-aqueous medium up to 40% (v/v non-aqueous content. The selectivity coefficient values indicate that the electrode is highly selective for Zn2+ over a number of other cations except Na+ and Cd2+. Although Na+ and Cd2+ are likely to cause some interference, they would not interfere if present at the concentrations < 1 ×10-5 and < 5 ×10-5 M, respectively. The electrode has been used as an indicator electrode to determine the end point in the potentiometric titration of Zn2+ with EDTA.

  16. Vision-Based Attitude and Formation Determination System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To determine pointing and position vectors in both local and inertial coordinate frames, multi-spacecraft missions typically utilize separate attitude determination...

  17. Diamond nanoparticles based biosensors for efficient glucose and lactate determination.

    Science.gov (United States)

    Briones, M; Casero, E; Petit-Domínguez, M D; Ruiz, M A; Parra-Alfambra, A M; Pariente, F; Lorenzo, E; Vázquez, L

    2015-06-15

    In this work, we report the modification of a gold electrode with undoped diamond nanoparticles (DNPs) and its applicability to the fabrication of electrochemical biosensing platforms. DNPs were immobilized onto a gold electrode by direct adsorption and the electrochemical behavior of the resulting DNPs/Au platform was studied. Four well-defined peaks were observed corresponding to the DNPs oxidation/reduction at the underlying gold electrode, which demonstrate that, although undoped DNPs have an insulating character, they show electrochemical activity as a consequence of the presence of different functionalities with unsaturated bonding on their surface. In order to develop a DNPs-based biosensing platform, we have selected glucose oxidase (GOx), as a model enzyme. We have performed an exhaustive study of the different steps involved in the biosensing platform preparation (DNPs/Au and GOx/DNPs/Au systems) by atomic force microscopy (AFM), field emission scanning electron microscopy (FE-SEM) and cyclic voltammetry (CV). The glucose biosensor shows a good electrocatalytic response in the presence of (hydroxymethyl)ferrocene as redox mediator. Once the suitability of the prototype system to determine glucose was verified, in a second step, we prepared a similar biosensor, but employing the enzyme lactate oxidase (LOx/DNPs/Au). As far as we know, this is the first electrochemical biosensor for lactate determination that includes DNPs as nanomaterial. A linear concentration range from 0.05 mM to 0.7 mM, a sensitivity of 4.0 µA mM(-1) and a detection limit of 15 µM were obtained. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Determining registered nurses' readiness for evidence-based practice.

    Science.gov (United States)

    Thiel, Linda; Ghosh, Yashowanto

    2008-01-01

    As health care systems worldwide move toward instituting evidence-based practice (EBP), its implementation can be challenging. Conducting a baseline assessment to determine nurses' readiness for EBP presents opportunities to plan strategies before implementation. Although a growing body of research literature is focused on implementing EBP, little attention has been paid to assessing nurses' readiness for EBP. The purpose of this study was to assess registered nurses' readiness for EBP in a moderate-sized acute care hospital in the Midwestern United States before implementation of a hospital-wide nursing EBP initiative. A descriptive cross-sectional survey design was used; 121 registered nurses completed the survey. The participants (n= 121) completed the 64-item Nurses' Readiness for Evidence-Based Practice Survey that allowed measurement of information needs, knowledge and skills, culture, and attitudes. Data were analyzed using descriptive statistics and a post hoc analysis. The majority (72.5%) of respondents indicated that when they needed information, they consulted colleagues and peers rather than using journals and books; 24% of nurses surveyed used the health database, Cumulative Index to Nursing & Allied Health Literature (CINAHL). The respondents perceived their EBP knowledge level as moderate. Cultural EBP scores were moderate, with unit scores being higher than organizational scores. The nurses' attitudes toward EBP were positive. The post hoc analysis showed many significant correlations. Nurses have access to technological resources and perceive that they have the ability to engage in basic information gathering but not in higher level evidence gathering. The elements important to EBP such as a workplace culture and positive attitudes are present and can be built upon. A "site-specific" baseline assessment provides direction in planning EBP initiatives. The Nurses' Readiness for EBP Survey is a streamlined tool with established reliability and

  19. Bias estimates used in lieu of validation of fission products and minor actinides in MCNP Keff calculations for PWR burnup credit casks

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Marshall, William BJ J [ORNL; Wagner, John C [ORNL; Bowen, Douglas G [ORNL

    2015-09-01

    The U.S. Nuclear Regulatory Commission (NRC) Division of Spent Fuel Storage and Transportation recently issued Interim Staff Guidance (ISG) 8, Revision 3. This ISG provides guidance for burnup credit (BUC) analyses supporting transport and storage of PWR pressurized water reactor (PWR) fuel in casks. Revision 3 includes guidance for addressing validation of criticality (keff) calculations crediting the presence of a limited set of fission products and minor actinides (FP&MA). Based on previous work documented in NUREG/CR-7109, recommendation 4 of ISG-8, Rev. 3, includes a recommendation to use 1.5 or 3% of the FP&MA worth to conservatively cover the bias due to the specified FP&MAs. This bias is supplementary to the bias and bias uncertainty resulting from validation of keff calculations for the major actinides in SNF and does not address extension to actinides and fission products beyond those identified herein. The work described in this report involves comparison of FP&MA worths calculated using SCALE and MCNP with ENDF/B-V, -VI, and -VII based nuclear data and supports use of the 1.5% FP&MA worth bias when either SCALE or MCNP codes are used for criticality calculations, provided the other conditions of the recommendation 4 are met. The method used in this report may also be applied to demonstrate the applicability of the 1.5% FP&MA worth bias to other codes using ENDF/B V, VI or VII based nuclear data. The method involves use of the applicant s computational method to generate FP&MA worths for a reference SNF cask model using specified spent fuel compositions. The applicant s FP&MA worths are then compared to reference values provided in this report. The applicants FP&MA worths should not exceed the reference results by more than 1.5% of the reference FP&MA worths.

  20. Sensitive determination of citrinin based on molecular imprinted electrochemical sensor

    Energy Technology Data Exchange (ETDEWEB)

    Atar, Necip [Department of Chemical Engineering, Faculty of Engineering, Pamukkale University, Denizli (Turkey); Yola, Mehmet Lütfi, E-mail: mehmetyola@gmail.com [Department of Metallurgical and Materials Engineering, Faculty of Engineering, Sinop University, Sinop (Turkey); Eren, Tanju [Department of Chemical Engineering, Faculty of Engineering, Pamukkale University, Denizli (Turkey)

    2016-01-30

    Graphical abstract: - Highlights: • Citrinin-imprinted electrochemical sensor is developed for the sensitive detection of citrinin. • The nanomaterial and citrinin-imprinted surfaces were characterized by several methods. • Citrinin-imprinted electrochemical sensor is sensitive and selective in analysis of food. • Citrinin-imprinted electrochemical sensor is preferred to the other methods. - Abstract: In this report, a novel molecular imprinted voltammetric sensor based on glassy carbon electrode (GCE) modified with platinum nanoparticles (PtNPs) involved in a polyoxometalate (H{sub 3}PW{sub 12}O{sub 40}, POM) functionalized reduced graphene oxide (rGO) was prepared for the determination of citrinin (CIT). The developed surfaces were characterized by using scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) method. CIT imprinted GCE was prepared via electropolymerization process of 80.0 mM pyrrole as monomer in the presence of phosphate buffer solution (pH 6.0) containing 20.0 mM CIT. The linearity range and the detection limit of the developed method were calculated as 1.0 × 10{sup −12}–1.0 × 10{sup −10} M and 2.0 × 10{sup −13} M, respectively. In addition, the voltammetric sensor was applied to rye samples. The stability and selectivity of the voltammetric sensor were also reported.

  1. A theoretically based determination of bowen-ratio fetch requirements

    Science.gov (United States)

    Stannard, D.I.

    1997-01-01

    Determination of fetch requirements for accurate Bowen-ratio measurements of latent- and sensible-heat fluxes is more involved than for eddy-correlation measurements because Bowen-ratio sensors are located at two heights, rather than just one. A simple solution to the diffusion equation is used to derive an expression for Bowen-ratio fetch requirements, downwind of a step change in surface fluxes. These requirements are then compared to eddy-correlation fetch requirements based on the same diffusion equation solution. When the eddy-correlation and upper Bowen-ratio sensor heights are equal, and the available energy upwind and downwind of the step change is constant, the Bowen-ratio method requires less fetch than does eddy correlation. Differences in fetch requirements between the two methods are greatest over relatively smooth surfaces. Bowen-ratio fetch can be reduced significantly by lowering the lower sensor, as well as the upper sensor. The Bowen-ratio fetch model was tested using data from a field experiment where multiple Bowen-ratio systems were deployed simultaneously at various fetches and heights above a field of bermudagrass. Initial comparisons were poor, but improved greatly when the model was modified (and operated numerically) to account for the large roughness of the upwind cotton field.

  2. {sup 14}C determination in different bio-based products

    Energy Technology Data Exchange (ETDEWEB)

    Santos Arévalo, Francisco-Javier, E-mail: fj.santos@csic.es [Centro Nacional de Aceleradores (Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Junta de Andalucía), Thomas Alva Edison 7, 41092 Seville (Spain); Gómez Martínez, Isabel; Agulló García, Lidia; Reina Maldonado, María-Teresa [Centro Nacional de Aceleradores (Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Junta de Andalucía), Thomas Alva Edison 7, 41092 Seville (Spain); García León, Manuel [Centro Nacional de Aceleradores (Universidad de Sevilla, Consejo Superior de Investigaciones Científicas, Junta de Andalucía), Thomas Alva Edison 7, 41092 Seville (Spain); Dpto. de Física Atómica Molecular y Nuclear, Universidad de Sevilla, Reina Mercedes s/n, 41012 Seville (Spain)

    2015-10-15

    Radiocarbon determination can be used as a tool to investigate the presence of biological elements in different bio-based products, such as biodiesel blends. These products may also be produced from fossil materials obtaining the same final molecules, so that composition is chemically indistinguishable. The amount of radiocarbon in these products can reveal how much of these biological elements have been used, usually mixed with petrol derived components, free of {sup 14}C. Some of these products are liquid and thus the handling at the laboratory is not as straightforward as with solid samples. At Centro Nacional de Aceleradores (CNA) we have tested the viability of these samples using a graphitization system coupled to an elemental analyzer used for combustion of the samples, thus avoiding any vacuum process. Samples do not follow any chemical pre-treatment procedure and are directly graphitized. Specific equipment for liquid samples related to the elemental analyzer was tested. Measurement of samples was performed by low-energy AMS at the 1 MV HVEE facility at CNA, paying special attention to background limits and reproducibility during sample preparation.

  3. Kinetic spectrophotometric determination of iron based on catalytic ...

    African Journals Online (AJOL)

    The relative standard deviation of the method was from 1.34% to 1.78% for 11 replicate determinations. The standard addition recovery of the method ranged from 95.71% to 103.3%. The method was used to determine iron in the black gingili paste, oat slice, sleeve-fish silk food samples. The determined results were in ...

  4. Extended burnup core management for once-through uranium fuel cycles in LWRS. First annual report for the period 1 July 1979-30 June 1980

    Energy Technology Data Exchange (ETDEWEB)

    Sesonske, A.

    1980-08-01

    Detailed core management arrangements are developed requiring four operating cycles for the transition from present three-batch loading to an extended burnup four-batch plan for Zion-1. The ARMP code EPRI-NODE-P was used for core modeling. Although this work is preliminary, uranium and economic savings during the transition cycles appear of the order of 6 percent.

  5. Impacts of burnup-dependent swelling of metallic fuel on the performance of a compact breed-and-burn fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hartanto, Donny; Heo, Woong; Kim, Chi Hyung; Kim, Yong Hee [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of)

    2016-04-15

    The U-Zr or U-TRU-Zr cylindrical metallic fuel slug used in fast reactors is known to swell significantly and to grow during irradiation. In neutronics simulations of metallic-fueled fast reactors, it is assumed that the slug has swollen and contacted cladding, and the bonding sodium has been removed from the fuel region. In this research, a realistic burnup-dependent fuel-swelling simulation was performed using Monte Carlo code McCARD for a single-batch compact sodium-cooled breed-and-burn reactor by considering the fuel-swelling behavior reported from the irradiation test results in EBR-II. The impacts of the realistic burnup-dependent fuel swelling are identified in terms of the reactor neutronics performance, such as core lifetime, conversion ratio, axial power distribution, and local burnup distributions. It was found that axial fuel growth significantly deteriorated the neutron economy of a breed-and-burn reactor and consequently impaired its neutronics performance. The bonding sodium also impaired neutron economy, because it stayed longer in the blanket region until the fuel slug reached 2% burnup.

  6. High-Pressure Liquid Chromatography of Irradiated Nuclear Fue - Separation of Neodymium for Burn-up Determination

    DEFF Research Database (Denmark)

    Larsen, N. R.

    1979-01-01

    Neodymium is separated from solutions of spent nuclear fuel by high-pressure liquid chromatography in methanol-nitric acid-water media using an anion-exchange column. Chromatograms obtained by monitoring at 280 nm, illustrate the difficulties especially with the fission product ruthenium in nuclear...... chemistry. Preseparation of the rare earths and trivalent actinides using a di(2-ethylhexyl)phosphoric acid/kieselguhr column is described....

  7. Autonomous Orbit Determination for Lagrangian Navigation Satellite Based on Neural Network Based State Observer

    Directory of Open Access Journals (Sweden)

    Youtao Gao

    2017-01-01

    Full Text Available In order to improve the accuracy of the dynamical model used in the orbit determination of the Lagrangian navigation satellites, the nonlinear perturbations acting on Lagrangian navigation satellites are estimated by a neural network. A neural network based state observer is applied to autonomously determine the orbits of Lagrangian navigation satellites using only satellite-to-satellite range. This autonomous orbit determination method does not require linearizing the dynamical mode. There is no need to calculate the transition matrix. It is proved that three satellite-to-satellite ranges are needed using this method; therefore, the navigation constellation should include four Lagrangian navigation satellites at least. Four satellites orbiting on the collinear libration orbits are chosen to construct a constellation which is used to demonstrate the utility of this method. Simulation results illustrate that the stable error of autonomous orbit determination is about 10 m. The perturbation can be estimated by the neural network.

  8. Determinants and outcomes of motivation in health professions education: a systematic review based on self-determination theory

    National Research Council Canada - National Science Library

    Orsini, Cesar; Binnie, Vivian I; Wilson, Sarah L

    2016-01-01

    This study aimed at conducting a systematic review in health professions education of determinants, mediators and outcomes of students' motivation to engage in academic activities based on the self...

  9. Vulcanization Kinetics of Natural Rubber Based On Free Sulfur Determination

    OpenAIRE

    Abu Hasan; Rochmadi Rochmadi; Hary Sulistyo; Suharto Honggokusumo

    2013-01-01

    The determination of free sulfur in the rubber vulcanizates provided significant representation of vulcanization reaction. In this research, the effects of vulcanization temperature, the mixing method of carbon black into rubber, the ingredients mixing sequence and the type of carbon black were studied on masticated and milled natural rubber in which the reaction was observed by un-reacted sulfur determination. The results showed that higher vulcanization temperature provided faster vulcaniza...

  10. Analysis of fresh fuel critical experiments appropriate for burnup credit validation

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, M.D.; Bowman, S.M.

    1995-10-01

    The ANS/ANS-8.1 standard requires that calculational methods used in determining criticality safety limits for applications outside reactors be validated by comparison with appropriate critical experiments. This report provides a detailed description of 34 fresh fuel critical experiments and their analyses using the SCALE-4.2 code system and the 27-group ENDF/B-IV cross-section library. The 34 critical experiments were selected based on geometry, material, and neutron interaction characteristics that are applicable to a transportation cask loaded with pressurized-water-reactor spent fuel. These 34 experiments are a representative subset of a much larger data base of low-enriched uranium and mixed-oxide critical experiments. A statistical approach is described and used to obtain an estimate of the bias and uncertainty in the calculational methods and to predict a confidence limit for a calculated neutron multiplication factor. The SCALE-4.2 results for a superset of approximately 100 criticals are included in uncertainty analyses, but descriptions of the individual criticals are not included.

  11. Determination of factors required to increase uptake of influenza vaccination among hospital-based healthcare workers

    NARCIS (Netherlands)

    Hopman, C.E.; Riphagen-Dalhuisen, J.; Looijmans-van den Akker, I; Frijstein, G.; Van der Geest-Blankert, A.D.; Danhof-Pont, M.B.; De Jager, H.J.; Bos, A.A.; Smeets, E.; De Vries, M.J.; Gallee, P.M.; Lenderink, A.F.; Hak, E.

    A questionnaire study was performed in all eight University Medical Centers in The Netherlands to determine the predictors of influenza vaccination compliance in hospital-based healthcare workers (HCWs). Demographical, behavioural and organisational determinants were assessed based on behavioural

  12. Determination of factors required to increase uptake of influenza vaccination among hospital-based healthcare workers

    NARCIS (Netherlands)

    Hopman, C. E.; Riphagen-Dalhuisen, J.; Looijmans-van den Akker, I.; Frijstein, G.; van der Geest-Blankert, A. D. J.; Danhof-Pont, M. B.; de Jager, H. J.; Bos, A. A.; Smeets, E.; de Vries, M. J. T.; Gallee, P. M. M.; Lenderink, A. F.; Hak, E.

    2011-01-01

    A questionnaire study was performed in all eight University Medical Centers in The Netherlands to determine the predictors of influenza vaccination compliance in hospital-based healthcare workers (HCWs). Demographical, behavioural and organisational determinants were assessed based on behavioural

  13. Determinants of Birthweight Outcomes: Quantile Regressions Based on Panel Data

    DEFF Research Database (Denmark)

    Bache, Stefan Holst; Dahl, Christian Møller; Kristensen, Johannes Tang

    to the possibility that smoking habits can be influenced through policy conduct. It is widely believed that maternal smoking reduces birthweight; however, the crucial difficulty in estimating such effects is the unobserved heterogeneity among mothers. We consider extensions of three panel data models to a quantile......Low birthweight outcomes are associated with large social and economic costs, and therefore the possible determinants of low birthweight are of great interest. One such determinant which has received considerable attention is maternal smoking. From an economic perspective this is in part due...... regression framework in order to control for heterogeneity and to infer conclusions about causality across the entire birthweight distribution. We obtain estimation results for maternal smoking and other interesting determinants, applying these to data obtained from Aarhus University Hospital, Skejby...

  14. A new PANI biosensor based on catalase for cyanide determination.

    Science.gov (United States)

    Özcan, Hakkı Mevlüt; Aydin, Tuba

    2016-01-01

    Cyanide is one of the most widespread of compounds measured in environmental analysis due to their toxic effects on environment and health. We report a highly sensitive, reliable, selective amperometric sensor for determination of cyanide, using a polyaniline conductive polymer. The enzyme catalase was immobilized by electropolymerization. The steps during the immobilization were controlled by electrochemical impedance spectroscopy. Optimum pH, temperature, aniline concentration, enzyme concentration, and the number of scans obtained during electropolymerization, were investigated. In addition, the cyanide present in artificial waste water samples was determined. In the characterization studies of the biosensor, some parameters such as reproducibility and storage stability, were analyzed.

  15. Determinants of technical inefficiency among maize-based farming ...

    African Journals Online (AJOL)

    Examining the level of farm-specific technical inefficiency of maize-based farming households in Niger state of Nigeria, this study fitted cross-sectional data into a Cobb- Douglass production frontier. Data used for this study were obtained using structured questionnaire administered to 108 randomly selected maize-based ...

  16. A Boltzmann Constant Determination Based on Johnson Noise Thermometry.

    Science.gov (United States)

    Flowers-Jacobs, N E; Pollarolo, A; Coakley, K J; Fox, A E; Rogalla, H; Tew, W L; Benz, S P

    2017-10-01

    A value for the Boltzmann constant was measured electronically using an improved version of the Johnson Noise Thermometry (JNT) system at the National Institute of Standards and Technology (NIST), USA. This system is different from prior ones, including those from the 2011 determination at NIST and both 2015 and 2017 determinations at the National Institute of Metrology (NIM), China. As in all three previous determinations, the main contribution to the combined uncertainty is the statistical uncertainty in the noise measurement, which is mitigated by accumulating and integrating many weeks of cross-correlated measured data. The second major uncertainty contribution also still results from variations in the frequency response of the ratio of the measured spectral noise of the two noise sources, the sense resistor at the triple-point of water and the superconducting quantum voltage noise source. In this paper, we briefly describe the major differences between our JNT system and previous systems, in particular the input circuit and approach we used to match the frequency responses of the two noise sources. After analyzing and integrating 49 days of accumulated data, we determined a value: k = 1.380 642 9(69)×10-23 J/K with a relative standard uncertainty of 5.0×10-6 and relative offset -4.05×10-6 from the CODATA 2014 recommended value.

  17. A Boltzmann constant determination based on Johnson noise thermometry

    Science.gov (United States)

    Flowers-Jacobs, N. E.; Pollarolo, A.; Coakley, K. J.; Fox, A. E.; Rogalla, H.; Tew, W. L.; Benz, S. P.

    2017-10-01

    A value for the Boltzmann constant was measured electronically using an improved version of the Johnson Noise Thermometry (JNT) system at the National Institute of Standards and Technology (NIST), USA. This system is different from prior ones, including those from the 2011 determination at NIST and both 2015 and 2017 determinations at the National Institute of Metrology (NIM), China. As in all three previous determinations, the main contribution to the combined uncertainty is the statistical uncertainty in the noise measurement, which is mitigated by accumulating and integrating many weeks of cross-correlated measured data. The second major uncertainty contribution also still results from variations in the frequency response of the ratio of the measured spectral noise of the two noise sources, the sense resistor at the triple-point of water and the superconducting quantum voltage noise source. In this paper, we briefly describe the major differences between our JNT system and previous systems, in particular the input circuit and approach we used to match the frequency responses of the two noise sources. After analyzing and integrating 50 d of accumulated data, we determined a value: k~=1.380 642 9(69)× {{10}-23} J K-1 with a relative standard uncertainty of 5.0× {{10}-6} and relative offset -4.05× {{10}-6} from the CODATA 2014 recommended value.

  18. Rehabilitation Priority Determination of Water Pipes Based on Hydraulic Importance

    Directory of Open Access Journals (Sweden)

    Do Guen Yoo

    2014-12-01

    Full Text Available This paper describes a study conducted to develop a method to facilitate more reliable determination of the rehabilitation priority order for water pipes by taking into account the pipes’ hydraulic importance. Existing methods use only the pipeline deterioration rate to determine the rehabilitation priority order. Accordingly, the deterioration rate under normal conditions and the hydraulic importance under abnormal conditions of water distribution pipelines were classified according to two different attributes. The deterioration rate of a water distribution pipeline was calculated in terms of the deterioration rate due to pipeline information factors and the deterioration rate resulting from the installation environment/external factors. The hydraulic importance of water distribution pipelines was calculated by considering the importance of a single pipe failure caused by water leakage or an accident and that of a multiple pipe failure caused by a disaster, such as an earthquake. These four attribute factors were employed in a multi-criteria decision-making process called a weighted utopian approach, developed in this study, that determines the final rehabilitation priority order for each pipeline. The study results indicate that the rehabilitation priority order can be determined more easily using this approach than with previously-developed methods and that the model developed is easier and more convenient to apply than existing rehabilitation priority order models that require a large amount of data, as well as complex failure probabilities and mathematical models.

  19. Voltammetric determination of heparin based on its interaction with

    African Journals Online (AJOL)

    a

    For example, Jiao et al. investigated the interaction between some cationic dyes such as azure A, methylene blue and azure B with heparin by absorption spectrophotometry [13]. Sun et al. applied brilliant cresyl blue and neutral red for spectrophotometric determination of heparin [14,. 15]. Liu et al. established a resonance ...

  20. Novel curcumin–based method of fluoride determination – the ...

    African Journals Online (AJOL)

    Fluoride concentrations above and below certain limits are deleterious to human health, having been implicated in diseases such as fluorosis, arthritis, caries, cancers etc. Better methods of its qualitative and quantitative determination are therefore necessary. A novel, less toxic and more environmentally friendly analytical ...

  1. Determining procedures for simulation-based training in radiology

    DEFF Research Database (Denmark)

    Nayahangan, Leizl Joy; Nielsen, Kristina Rue; Albrecht-Beste, Elisabeth

    2018-01-01

    OBJECTIVES: New training modalities such as simulation are widely accepted in radiology; however, development of effective simulation-based training programs is challenging. They are often unstructured and based on convenience or coincidence. The study objective was to perform a nationwide needs...... assessment to identify and prioritize technical procedures that should be included in a simulation-based curriculum. METHODS: A needs assessment using the Delphi method was completed among 91 key leaders in radiology. Round 1 identified technical procedures that radiologists should learn. Round 2 explored...... in radiology. • Development of simulation-based training should follow a structured approach. • The CAMES Needs Assessment Formula explores needs for simulation training. • A national Delphi study identified and prioritized procedures suitable for simulation training. • The prioritized list serves as guide...

  2. An ensemble of dissimilarity based classifiers for Mackerel gender determination

    Science.gov (United States)

    Blanco, A.; Rodriguez, R.; Martinez-Maranon, I.

    2014-03-01

    Mackerel is an infravalored fish captured by European fishing vessels. A manner to add value to this specie can be achieved by trying to classify it attending to its sex. Colour measurements were performed on Mackerel females and males (fresh and defrozen) extracted gonads to obtain differences between sexes. Several linear and non linear classifiers such as Support Vector Machines (SVM), k Nearest Neighbors (k-NN) or Diagonal Linear Discriminant Analysis (DLDA) can been applied to this problem. However, theyare usually based on Euclidean distances that fail to reflect accurately the sample proximities. Classifiers based on non-Euclidean dissimilarities misclassify a different set of patterns. We combine different kind of dissimilarity based classifiers. The diversity is induced considering a set of complementary dissimilarities for each model. The experimental results suggest that our algorithm helps to improve classifiers based on a single dissimilarity.

  3. X-Ray Pulsar Based Navigation and Time Determination Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm will build on the Phase I X-ray pulsar-based navigation and timing (XNAV) feasibility assessment to develop a detailed XNAV simulation capability to...

  4. Local determinants of crime: Do military bases matter?

    Directory of Open Access Journals (Sweden)

    Alfredo Paloyo

    2014-09-01

    Full Text Available Background: The majority of crime is committed by young men, and young men comprise the majority of the military-base population. The confluence of these two empirical regularities invites a scientific look at the contribution of a military base to criminal activity in ist geographic periphery. Objective: We estimate the impact on criminal activity of the massive base realignments and closures that occurred in Germany for the period 2003-2007. In particular, we examine breaking and entering, automobile-related crime, violent crime, and drug-related crime. Methods: We use a fixed-effect model to account for time-invariant unobservables in a panel of 298 military bases. We also take advantage of geographic information system software to mitigate issues arising from the spatial nature of the dataset. Results: The estimates indicate that the base realignments and closures did not have a significant impact on criminal activity surrounding the base. Traditional correlates of crime remain statistically significant in our specifications. Conclusions: Although crime is largely committed by young men, we find that the closure of military bases, which are staffed primarily by young men, does not have an impact on criminal activity. For matters of regional policy, we find that arguments pertaining to criminal activity generated by military bases are not supported by the data. Comments: Economic well-being, as measured by real GNP and relative disposable income, is negatively associated with crime. Higher unemployment has a positive association. Regions with higher share of foreigners also have higher crime levels.

  5. Impact of neutron thermal scattering laws on the burn-up analysis of supercritical LWR's fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Conti, Andrea

    2011-10-15

    . The third, most naive option is called the ''free gas approximation''. It is the goal of this work to make an estimate of the criticality calculations' inaccuracy due to the inadequate employed physical model and to determine which one of the available models can be the best replacement. The accuracy of criticality calculations referring to the HPLWR is a problem that had already been raised by Waata in 2006. In her Ph.D. thesis Waata reports having carried out MCNP runs referring to an HPLWR fuel element employing the free gas approximation. In her thesis Waata explicitly sifts through the factors that can affect her MCNP runs' accuracy, but leaves the inappropriate thermal treatment completely out. In this work, the inaccuracy of the criticality calculations has been investigated carrying out sets of similar burn-up calculations differing from each other only in the applied thermal cross section sets. The widest discrepancies were detected between the results obtained applying the free gas model and those obtained applying the molecular models. This, in conjunction with the fact that the free gas model does not even keep in count the molecular structure of H{sub 2}O suggest to discard it and to focus the investigation on the vapour and liquid models. Dr. J. Marti, from the Universitat Politecnica de Catalunya, Barcelona, Spain registered the generalized frequency distributions obtained from the molecular dynamics simulations of 216 molecules of H{sub 2}O in 10 simulated supercritical states and published in an article (1999) the frequencies of the three characteristic distribution peaks for each simulated state, in numerical format. A confrontation with the corresponding peaks from Bernnat's available frequency distributions for liquid water and vapour revealed the peaks of the latter to be closest to the supercritical water ones in nearly all cases. Hence the inference that thermal cross section sets for vapour are for the time

  6. Determinants and outcomes of motivation in health professions education: a systematic review based on self-determination theory

    OpenAIRE

    Orsini, Cesar; Binnie, Vivian I.; Sarah L. Wilson

    2016-01-01

    Purpose:\\ud This study aimed at conducting a systematic review in health professions education of determinants, mediators and outcomes of students’ motivation to engage in academic activities based on the self-determination theory’s perspective.\\ud Methods:\\ud A search was conducted across databases (MEDLINE, CINHAL, EMBASE, PsycINFO, and ERIC databases), hand-search of relevant journals, grey literature, and published research profile of key authors. Quantitative and qualitative studies were...

  7. An improved velocity determination method based on GOCE kinematic orbit

    Directory of Open Access Journals (Sweden)

    Jiang Nan

    2013-05-01

    Full Text Available A new velocity determination algorithm with combination of remove and restore method, outliers detection method and Chebyshev fitting method with redundant observations is proposed. An optimal selection of number of sampling points is given. The result shows that, when the number of sampling points is 19, the three-dimension (3D interpolation precision of velocity is superior to 0.1 mm/s, which is above 3 times better than that of Chebyshev fitting method with redundant observations and far better than those of the conventional interpolation methods.

  8. Anatomical and procedural determinants of catheter-based renal denervation

    NARCIS (Netherlands)

    Ewen, Sebastian; Ukena, Christian; Lüscher, Thomas Felix; Bergmann, Martin; Blankestijn, Peter J|info:eu-repo/dai/nl/086704850; Blessing, Erwin; Cremers, Bodo; Dörr, Oliver; Hering, Dagmara; Kaiser, Lukas; Nef, Holger; Noory, Elias; Schlaich, Markus; Sharif, Faisal; Sudano, Isabella; Vogel, Britta; Voskuil, Michiel|info:eu-repo/dai/nl/254745954; Zeller, Thomas; Tzafriri, Abraham R; Edelman, Elazer R; Lauder, Lucas; Scheller, Bruno; Böhm, Michael; Mahfoud, Felix

    2016-01-01

    BACKGROUND/PURPOSE: Catheter-based renal sympathetic denervation (RDN) can reduce blood pressure (BP) and sympathetic activity in certain patients with uncontrolled hypertension. Less is known about the impact of renal anatomy and procedural parameters on subsequent BP response. METHODS/MATERIALS: A

  9. Determination of Absolute Zero Using a Computer-Based Laboratory

    Science.gov (United States)

    Amrani, D.

    2007-01-01

    We present a simple computer-based laboratory experiment for evaluating absolute zero in degrees Celsius, which can be performed in college and undergraduate physical sciences laboratory courses. With a computer, absolute zero apparatus can help demonstrators or students to observe the relationship between temperature and pressure and use…

  10. Experimental Bifurcation Analysis By Control-based Continuation - Determining Stability’

    DEFF Research Database (Denmark)

    Bureau, Emil; Santos, Ilmar; Thomsen, Jon Juel

    2012-01-01

    stable and unstable equilibrium states. We present the ongoing work of developing and applying the control-based continuation method to an experimental mechanical test-rig, consisting of a harmonically forced nonlinear impact oscillator controlled by electromagnetic actuators. Furthermore we propose...

  11. Determinants of Inequality in Cameroon: A Regression-Based ...

    African Journals Online (AJOL)

    2008-07-22

    Jul 22, 2008 ... regression-based decomposition (RBD) analysis can shed more light to our understanding of factors that ..... analysis (MCA) method that captures the multidimensional notion of health and education. Moreover ..... A key result that can be identified from this reading is the role of spatial inequality, as made.

  12. Determining the Strategic Consolidation of the Capital Base of ...

    African Journals Online (AJOL)

    This paper employed Analytic Hierarchy Process (AHP) as an evaluative tool for strategic reconsolidation of capital base by banks, using the recent experience of six merger/acquisition banks. The aim of the study specifically was to evaluate whether decisions taken by the various groups of banks in meeting the $166.7 ...

  13. On the condition of UO2 nuclear fuel irradiated in a PWR to a burn-up in excess of 110 MWd/kgHM

    Science.gov (United States)

    Restani, R.; Horvath, M.; Goll, W.; Bertsch, J.; Gavillet, D.; Hermann, A.; Martin, M.; Walker, C. T.

    2016-12-01

    Post-irradiation examination results are presented for UO2 fuel from a PWR fuel rod that had been irradiated to an average burn-up of 105 MWd/kgHM and showed high fission gas release of 42%. The radial distribution of xenon and the partitioning of fission gas between bubbles and the fuel matrix was investigated using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and electron probe microanalysis. It is concluded that release from the fuel at intermediate radial positions was mainly responsible for the high fission gas release. In this region thermal release had occurred from the high burn-up structure (HBS) at some point after the sixth irradiation cycle. The LA-ICP-MS results indicate that gas release had also occurred from the HBS in the vicinity of the pellet periphery. It is shown that the gas pressure in the HBS pores is well below the pressure that the fuel can sustain.

  14. Vulcanization Kinetics of Natural Rubber Based On Free Sulfur Determination

    Directory of Open Access Journals (Sweden)

    Abu Hasan

    2013-05-01

    Full Text Available The determination of free sulfur in the rubber vulcanizates provided significant representation of vulcanization reaction. In this research, the effects of vulcanization temperature, the mixing method of carbon black into rubber, the ingredients mixing sequence and the type of carbon black were studied on masticated and milled natural rubber in which the reaction was observed by un-reacted sulfur determination. The results showed that higher vulcanization temperature provided faster vulcanization reaction and greater reaction rate constant. Similarly, the mixing sequence of ingredient and carbon black into rubber influenced the rate of vulcanization reaction. The subsequent ingredients mixing sequence, in this case, resulted in higher vulcanization rate compared to that of the simultaneous one. However, the mixing method of carbon black into rubber brought small effect on the rate of vulcanization reaction. The type of carbon black applied was observed to influence the reaction rate of vulcanization. Smaller particle sizes of carbon black gave larger reaction rate constant. In this case, the type of carbon black N 330 gave faster vulcanization rate than that of N 660.

  15. PLUTON: Three-group neutronic code for burnup analysis of isotope generation and depletion in highly irradiated LWR fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Lemehov, Sergei E; Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-08-01

    PLUTON is a three-group neutronic code analyzing, as functions of time and burnup, the change of radial profiles, together with average values, of power density, burnup, concentration of trans-uranium elements, plutonium buildup, depletion of fissile elements, and fission product generation in water reactor fuel rod with standard UO{sub 2}, UO{sub 2}-Gd{sub 2}O{sub 3}, inhomogeneous MOX, and UO{sub 2}-ThO{sub 2}. The PLUTON code, which has been designed to be run on Windows PC, has adopted a theoretical shape function of neutron attenuation in pellet, which enables users to perform a very fast and accurate calculation easily. The present code includes the irradiation conditions of the Halden Reactor which gives verification data for the code. The total list of trans-uranium elements included in the calculations consists of {sub 92}U{sup 233-239}, {sub 93}Np{sup 237-239}, {sub 94}Pu{sup 238-243}, {sub 95}Am{sup 241-244} (including isomers), and {sub 96}Cm{sup 242-245}. Poisoning fission products are represented by {sub 54}Xe{sup 131,133,135}, {sub 48}Cd{sup 113}, {sub 62}Sm{sup 149,151,152}, {sub 64}Gd{sup 154-160}, {sub 63}Eu{sup 153,155}, {sub 36}Kr{sup 83,85}, {sub 42}Mo{sup 95}, {sub 43}Tc{sup 99}, {sub 45}Rh{sup 103}, {sub 47}Ag{sup 109}, {sub 53}I{sup 127,129,131}, {sub 55}Cs{sup 133}, {sub 57}La{sup 139}, {sub 59}Pr{sup 141}, {sub 60}Nd{sup 143-150}, {sub 61}Pm{sup 147}. Fission gases and volatiles included in the code are {sub 36}Kr{sup 83-86}, {sub 54}Xe{sup 129-136}, {sub 52}Te{sup 125-130}, {sub 53}I{sup 127-131}, {sub 55}Cs{sup 133-137}, and {sub 56}Ba{sup 135-140}. Verification has been performed up to 83 GWd/tU, and a satisfactory agreement has been obtained. (author)

  16. Security management based on trust determination in cognitive radio networks

    Science.gov (United States)

    Li, Jianwu; Feng, Zebing; Wei, Zhiqing; Feng, Zhiyong; Zhang, Ping

    2014-12-01

    Security has played a major role in cognitive radio networks. Numerous researches have mainly focused on attacking detection based on source localization and detection probability. However, few of them took the penalty of attackers into consideration and neglected how to implement effective punitive measures against attackers. To address this issue, this article proposes a novel penalty mechanism based on cognitive trust value. The main feature of this mechanism has been realized by six functions: authentication, interactive, configuration, trust value collection, storage and update, and punishment. Data fusion center (FC) and cluster heads (CHs) have been put forward as a hierarchical architecture to manage trust value of cognitive users. Misbehaving users would be punished by FC by declining their trust value; thus, guaranteeing network security via distinguishing attack users is of great necessity. Simulation results verify the rationality and effectiveness of our proposed mechanism.

  17. Synthesis/literature review for determining structural layer coefficients (SLC) of bases.

    Science.gov (United States)

    2014-12-01

    FDOTs current method of determining a base material structural layer coefficient (SLC) is detailed in the : Materials Manual, Chapter 2.1, Structural Layer Coefficients for Flexible Pavement Base Materials. : Currently, any new base material not a...

  18. Determination of anisotropy and multimorphology in fly ash based geopolymers

    Science.gov (United States)

    Khan, M. Irfan; Azizli, Khairun; Sufian, Suriati; Man, Zakaria; Siyal, Ahmer Ali; Ullah, Hafeez

    2015-07-01

    In this study, Malaysian coal fly ash-based geopolymers were investigated for its morphology and chemical composition using scanning electron microscopy coupled with energy dispersive X-rays (SEM-EDX). Geopolymer was synthesized using sodium hydroxide as activator. SEM studies revealed multiphasous structure of the material, composed of geopolymeric gel, partially reacted fly ashparticles and selectively leached particles. EDX analysis confirmed the chemical composition of different regions. Infra red spectroscopic studies supported the SEM-EDX analysis by confirming presence of unreacted quartzite and mullite in geopolymers. It is concluded that geopolymers possese a non uniform chemistry through out the structure.

  19. Determination of anisotropy and multimorphology in fly ash based geopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Khan, M. Irfan, E-mail: mirfanwazir@gmail.com; Azizli, Khairun, E-mail: khairun-azizli@petronas.com.my; Sufian, Suriati, E-mail: suriati@petronas.com.my; Man, Zakaria, E-mail: zakaman@petronas.com.my; Siyal, Ahmer Ali, E-mail: ahmersiyal@gmail.com; Ullah, Hafeez, E-mail: Hafeez-wazir@yahoo.com [Department of Chemical Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750, Tronoh, Perak (Malaysia)

    2015-07-22

    In this study, Malaysian coal fly ash-based geopolymers were investigated for its morphology and chemical composition using scanning electron microscopy coupled with energy dispersive X-rays (SEM-EDX). Geopolymer was synthesized using sodium hydroxide as activator. SEM studies revealed multiphasous structure of the material, composed of geopolymeric gel, partially reacted fly ashparticles and selectively leached particles. EDX analysis confirmed the chemical composition of different regions. Infra red spectroscopic studies supported the SEM-EDX analysis by confirming presence of unreacted quartzite and mullite in geopolymers. It is concluded that geopolymers possese a non uniform chemistry through out the structure.

  20. Isotopic analyses and calculation by use of JENDL-3.2 for high burn-up UO{sub 2} and MOX spent fuels

    Energy Technology Data Exchange (ETDEWEB)

    Sasahara, Akihiro; Matsumura, Tetsuo [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab.; Nicolaou, G.; Betti, M.; Walker, C.T.

    1997-03-01

    The post irradiation examinations (PIE) were carried out for high burn-up UO{sub 2} spent fuel (3.8%U235, average burn-up:60GWd/t) and mixed oxide (MOX) spent fuel (5.07%Pu, average burn-up:45GWd/t). The PIE includes, (a) isotopic analysis, (b) electron probe microanalysis (EPMA) in pellet cross section and so on. The results of isotopic analyses and EPMA were compared with ORIGEN2/82 and VIM-BURN calculation results. In VIM-BURN calculation, the nuclear data of actinides were proceeded from new data file, JENDL-3.2. The sensitivities of power history and moderator density to nuclides composition were investigated by VIM-BURN calculation and consequently power history mainly effected on Am241 and Am242m and moderator density effected on fissile nuclides. From EPMA results of U and Pu distribution in pellet, VIM-BURN calculation showed reasonable distribution in pellet cross section. (author)

  1. Burnup calculations using the OREST computer code for uranium dioxide fuel elements of boiling water reactors. Abbrandberechnung mit OREST fuer Urandioxid-Siedewasserreaktor-Brennelemente

    Energy Technology Data Exchange (ETDEWEB)

    Hesse, U.

    1991-01-01

    There are plans to also use plutonium containing fuel elements (mixed oxide fuel) in the BWR type reactors, with a proportion of up to one third of the entire fuel core. The new concept uses complete MOX fuel elements, as are used in the PWR type reactors. The OREST computer code has been designed for burnup calculations in PWRs. The situation in BWRs is different, as in these reactor types, fuel elements are heterogenous in design, and burnup calculations have to take into account the axial variations of the void fraction, so that multi-dimensional effects have to be calculated. The report explains that the one-dimensional OREST code can be enhanced by supplementing calculations, performed with the Monte-Carlo type KENO code in this case, and is thus suitable without restrictions for performing burnup calculations for MOX fuel elements in BWRs. The calculation method and performance is illustrated by the example of a UO{sub 2} fuel element of the Wuergassen reactor. The model calculations predict a relatively high residual activity in the upper part of the fuel element, and a distinct curium buildup in the lower third of the BWR fuel element. (orig./HP).

  2. Evaluation of the elastic constants of the high burnup nuclear fuel (U{sub 1-y},Gd{sub y})O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Luciana T.; Dias, Marcio S., E-mail: ltl@cdtn.b, E-mail: marciod@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Nuclear fuels with burnable poisons are applications in the scope of the nuclear energy for electricity generation. The discharge burnups of this type of fuel are higher than the discharge burnups of pure UO{sub 2} fuels with same enrichment of the fissile element. In conditions of high burnups and moderate transients, the fuel rods can be subject to the pellet/cladding mechanical interactions (PCMI). Elastic constants of the fuel and cladding are used in the thermo-mechanical evaluation of the PCMI. The fuel elastic constants are usually expressed as a function of temperature, composition and porosity. Data survey and modeling of elastic constants for the (U{sub 1-y},Gd{sub y})O{sub 2} fuel are developed in this paper. Due to small amount of the available measurements for the (U{sub 1-y},Gd{sub y})O{sub 2}, the modeling taken into account the data from UO{sub 2} and Gd{sub 2}O{sub 3} measurements. Available measurements of the Al{sub 2}O{sub 3} were also used in the model validation. The elastic constants of these materials have been fitted by an analytic equation, which depicts the whole range the dependences. (author)

  3. Determinants and outcomes of motivation in health professions education: a systematic review based on self-determination theory.

    Science.gov (United States)

    Orsini, Cesar; Binnie, Vivian I; Wilson, Sarah L

    2016-01-01

    This study aimed at conducting a systematic review in health professions education of determinants, mediators and outcomes of students' motivation to engage in academic activities based on the self-determination theory's perspective. A search was conducted across databases (MEDLINE, CINHAL, EMBASE, PsycINFO, and ERIC databases), hand-search of relevant journals, grey literature, and published research profile of key authors. Quantitative and qualitative studies were included if they reported research in health professions education focused on determinants, mediators, and/or outcomes of motivation from the self-determination and if meeting the quality criteria. A total of 17 studies met the inclusion and quality criteria. Articles retrieved came from diverse locations and mainly from medical education and to a lesser extent from psychology and dental education. Intrapersonal (gender and personality traits) and interpersonal determinants (academic conditions and lifestyle, qualitative method of selection, feedback, and an autonomy supportive learning climate) have been reported to have a positive influence on students' motivation to engage in academic activities. No studies were found that tested mediation effects between determinants and students' motivation. In turn, students' self-determined motivation has been found to be positively associated with different cognitive, affective, and behavioural outcomes. This study has found that generally, motivation could be enhanced by changes in the educational environment and by an early detection of students' characteristics. Doing so may support future health practitioners' self-determined motivation and positively influence how they process information and their emotions and how they approach their learning activities.

  4. Color difference threshold determination for acrylic denture base resins.

    Science.gov (United States)

    Ren, Jiabao; Lin, Hong; Huang, Qingmei; Liang, Qifan; Zheng, Gang

    2015-01-01

    This study aimed to set evaluation indicators, i.e., perceptibility and acceptability color difference thresholds, of color stability for acrylic denture base resins for a spectrophotometric assessing method, which offered an alternative to the visual method described in ISO 20795-1:2013. A total of 291 disk specimens 50±1 mm in diameter and 0.5±0.1 mm thick were prepared (ISO 20795-1:2013) and processed through radiation tests in an accelerated aging chamber (ISO 7491:2000) for increasing times of 0 to 42 hours. Color alterations were measured with a spectrophotometer and evaluated using the CIE L*a*b* colorimetric system. Color differences were calculated through the CIEDE2000 color difference formula. Thirty-two dental professionals without color vision deficiencies completed perceptibility and acceptability assessments under controlled conditions in vitro. An S-curve fitting procedure was used to analyze the 50:50% perceptibility and acceptability thresholds. Furthermore, perceptibility and acceptability against the differences of the three color attributes, lightness, chroma, and hue, were also investigated. According to the S-curve fitting procedure, the 50:50% perceptibility threshold was 1.71ΔE00 (r(2)=0.88) and the 50:50% acceptability threshold was 4.00 ΔE00 (r(2)=0.89). Within the limitations of this study, 1.71/4.00 ΔE00 could be used as perceptibility/acceptability thresholds for acrylic denture base resins.

  5. Community-Based Intervention Determines Tele-Audiology Site Candidacy.

    Science.gov (United States)

    Coco, Laura; Champlin, Craig A; Eikelboom, Robert H

    2016-10-01

    Sections of the community face barriers to accessing audiology services. The aim of this study was to assess the barriers faced by people in typically underserved community settings and to provide audiology services in their natural environment. Information gathered by questionnaire was used to determine each site's candidacy as a potential tele-audiology site. Sixty-three participants were recruited across 3 community sites that were identified as gathering places for individuals who experience barriers to accessing traditional clinical audiology services. Information about demographics and participant experience with barriers to access was gathered by a locally generated, self-administered questionnaire. Pure-tone air-conduction audiometric exams were performed on participants with an automated portable diagnostic audiometer. Afterward, the investigator provided counseling regarding hearing loss rehabilitation or hearing protection. Referrals were made when appropriate. Pure-tone averages were similar within sites but varied across sites. At least 30% of individuals at each site reported they wanted to visit the audiologist more often. Each site reported different principal barriers to access, among them transportation, motivation, and money. Eleven individuals were referred to the next level of care. Questionnaire results revealed special accommodations should be considered at each potential tele-audiology site. The present study provided audiology services to individuals in their natural environment, identified many of the obstacles preventing individuals from pursuing traditional audiology services and provided information for the foundation of a tele-audiology practice.

  6. Uncovering attribute-based determinants of loyalty in cigarette brands

    DEFF Research Database (Denmark)

    Krystallis Krontalis, Athanasios

    2013-01-01

    smokers to switch across brands and within family brands, resulting on improved market performance and loyalty levels. Length and thickness-related differentiation are slightly better than nondifferentiation in inducing loyalty, but worse in improving performance. Practical implications – Two types...... of categorization prevail in the category: first, a family brand-based, mainly relevant for large brands; and second, an attribute-driven, apparent for small family brands. Two types of switching behaviors can also be considered: first within family brands, switching among product attributes for the larger brands......; and second within product attributes, switching among family brands for smaller brands. Social implications – These findings have profound implications for the development of anti-smoking policy in terms of the exact functioning of product differentiation as part of the tobacco industry’s strategy. Public...

  7. Acetylcholinesterase inhibition-based biosensors for pesticide determination: a review.

    Science.gov (United States)

    Pundir, Chandra Shekhar; Chauhan, Nidhi

    2012-10-01

    Pesticides released intentionally into the environment and through various processes contaminate the environment. Although pesticides are associated with many health hazards, there is a lack of monitoring of these contaminants. Traditional chromatographic methods-high-performance liquid chromatography, capillary electrophoresis, and mass spectrometry-are effective for the analysis of pesticides in the environment but have certain limitations such as complexity, time-consuming sample preparation, and the requirement of expensive apparatus and trained persons to operate. Over the past decades, acetylcholinesterase (AChE) inhibition-based biosensors have emerged as simple, rapid, and ultra-sensitive tools for pesticide analysis in environmental monitoring, food safety, and quality control. These biosensors have the potential to complement or replace the classical analytical methods by simplifying or eliminating sample preparation and making field-testing easier and faster with significant decrease in cost per analysis. This article reviews the recent developments in AChE inhibition-based biosensors, which include various immobilization methods, different strategies for biosensor construction, the advantages and roles of various matrices used, analytical performance, and application methods for constructing AChE biosensors. These AChE biosensors exhibited detection limits and linearity in the ranges of 1.0×10(-11) to 42.19 μM (detection limits) and 1.0×10(-11)-1.0×10(-2) to 74.5-9.9×10(3)μM (linearity). These biosensors were stable for a period of 2 to 120days. The future prospects for the development of better AChE biosensing systems are also discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Relationship between changes in the crystal lattice strain and thermal conductivity of high burnup UO{sub 2} pellets

    Energy Technology Data Exchange (ETDEWEB)

    Amaya, Masaki, E-mail: amaya.masaki@jaea.go.j [Fuel Safety Research Group, Nuclear Safety Research Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Nakamura, Jinichi; Fuketa, Toyoshi [Fuel Safety Research Group, Nuclear Safety Research Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Kosaka, Yuji [Nuclear Development Corporation, 622-12, Funaishikawa, Tokai-mura, Naka-gun, Ibaraki 319-1111 (Japan)

    2010-01-01

    Two kinds of disk-shaped UO{sub 2} samples (4 mm in diameter and 1 mm in thickness) were irradiated in a test reactor up to about 60 and 130 GWd/t, respectively. The microstructures of the samples were investigated by means of optical microscopy, scanning electron microscopy/ electron probe micro-analysis (SEM/EPMA) and micro-X-ray diffractometry. The measured lattice parameters tended to be considerably smaller than the reported values, and the typical cauliflower structure which is often observed in high burnup fuel pellet is hardly seen in these samples. Thermal diffusivities of the samples were also measured by using a laser flash method, and their thermal conductivities were evaluated by multiplying the heat capacity of unirradiated UO{sub 2} and sample densities. While the thermal conductivities of sample 2 showed recovery after being annealed at 1500 K, those of sample 4 were not clearly observed even after being annealed at 1500 K. These trends suggest that the amount of accumulated irradiation-induced defects depends on the irradiation condition of each sample. From the comparison of the changes in the lattice parameter and strain energy density before and after the thermal diffusivity measurements, it is likely that the thermal conductivity recovery in the temperature region from 1200 to 1500 K is related to the migration of dislocation.

  9. Analysis of burnup of Angra 2 PWR nuclear with addition of thorium dioxide fuel using ORIGEN-ARP

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Isadora C.; Wichrowski, Caio C.; Oliveira, Claudio L. de; Vellozo, Sergio O.; Baptista, Camila O., E-mail: isadora.goncalves@ime.eb.br, E-mail: wichrowski@ime.eb.br, E-mail: d7luiz@yahoo.com.br, E-mail: vellozo@ime.eb.br, E-mail: camila.oliv.baptista@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Nuclear

    2017-11-01

    It is known that isotope {sup 232}thorium is a fertile nuclide with the ability to convert into {sup 233}uranium, a potentially fissile isotope, after absorbing a neutron. As there is a large stock of available thorium in the world, this element shows great promise in mitigate the world energy crisis, more particularly in the problem of uranium scarcity, besides being an alternative nuclear fuel for those currently used in reactors, and yet presenting advantages as an option for the non-proliferation movement, among others. In this study, the analysis of the remaining nuclides of burnup was carried out for the core configuration of a PWR (pressurized water reactor) reactor, specifically the Angra 2 reactor, using only uranium dioxide, its current configuration, and in different configurations including a mixed oxide of uranium and thorium in three concentrations, allowing a preliminary assessment of the feasibility of the modification of the fuel, the resulting production of {sup 233}uranium, the emergence of {sup 231}protactinium (an isotope that only occurs as a fission product of {sup 232}Th) resulting from burning. The study was carried out using data obtained from FSAR (Final Safety Analysis Report) of Angra 2, using the SCALE 6.1, a modeling and simulation nuclear code, especially its ORIGEN-ARP module, which analyzes the depletion of isotopes presents in a reactor. (author)

  10. A Concise Design for the Irradiation of U–10Zr Metallic Fuel at a Very Low Burnup

    Directory of Open Access Journals (Sweden)

    Haibing Guo

    2017-06-01

    Full Text Available In order to investigate the swelling behavior and fuel–cladding interaction mechanism of U–10Zr alloy metallic fuel at very low burnup, an irradiation experiment was concisely designed and conducted on the China Mianyang Research Reactor. Two types of irradiation samples were designed for studying free swelling without restraint and the fuel–cladding interaction mechanism. A new bonding material, namely, pure aluminum powder, was used to fill the gap between the fuel slug and sample shell for reducing thermal resistance and allowing the expansion of the fuel slug. In this paper, the concise irradiation rig design is introduced, and the neutronic and thermal–hydraulic analyses, which were carried out mainly using MCNP (Monte Carlo N-Particle and FLUENT codes, are presented. Out-of-pile tests were conducted prior to irradiation to verify the manufacturing quality and hydraulic performance of the rig. Nondestructive postirradiation examinations using cold neutron radiography technology were conducted to check fuel cladding integrity and swelling behavior. The results of the preliminary examinations confirmed the safety and effectiveness of the design.

  11. A concise design o the irradiation of U-10Zr metallic fuel at a very low burnup

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hai Bing; Zhou, Wei; Sun, Yong; Qian, Dazhi; Ma, Jimin; Leng, Jun; Huo, Hyoung; Wang, Shaohua [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang (China)

    2017-06-15

    In order to investigate the swelling behavior and fuel–cladding interaction mechanism of U–10Zr alloy metallic fuel at very low burnup, an irradiation experiment was concisely designed and conducted on the China Mianyang Research Reactor. Two types of irradiation samples were designed for studying free swelling without restraint and the fuel–cladding interaction mechanism. A new bonding material, namely, pure aluminum powder, was used to fill the gap between the fuel slug and sample shell for reducing thermal resistance and allowing the expansion of the fuel slug. In this paper, the concise irradiation rig design is introduced, and the neutronic and thermal–hydraulic analyses, which were carried out mainly using MCNP (Monte Carlo N-Particle) and FLUENT codes, are presented. Out-of-pile tests were conducted prior to irradiation to verify the manufacturing quality and hydraulic performance of the rig. Nondestructive postirradiation examinations using cold neutron radiography technology were conducted to check fuel cladding integrity and swelling behavior. The results of the preliminary examinations confirmed the safety and effectiveness of the design.

  12. Prominent Determinants of Consumer-Based Brand Equity

    Directory of Open Access Journals (Sweden)

    Elisa Battistoni

    2013-08-01

    Full Text Available In this paper we investigate the most prominent drivers of brand equity, from a consumerbased point of view. We present a new approach for measuring brand equity, which can be applied regardless of the brand sector and is based on the Analytic Hierarchy Process. This approach has the main advantage of allowing for comparisons to be made between non‐directly measurable elements and also has the advantage of enabling the ranking of intangible criteria, such as consumers’ feelings or purchase intentions. We focus on the fashion industry, since we believe in the higher value of our approach when applied to brands which offer products with less tangible characteristics. Thanks to a case study – which involved about 250 interviewees – we succeed in finding and prioritizing the elements which can have an impact on the brand value. We also provide a global ranking for three apparel brands: Gap, H&M and Zara. The results from our model are consistent with other popular ratings and can be extremely useful for brand managers.

  13. 12 CFR 652.75 - Your responsibility for determining the risk-based capital level.

    Science.gov (United States)

    2010-01-01

    ... SYSTEM FEDERAL AGRICULTURAL MORTGAGE CORPORATION FUNDING AND FISCAL AFFAIRS Risk-Based Capital Requirements § 652.75 Your responsibility for determining the risk-based capital level. (a) You must determine your risk-based capital level using the procedures in this subpart, appendix A to this subpart, and any...

  14. Determinants and outcomes of motivation in health professions education: a systematic review based on self-determination theory

    Directory of Open Access Journals (Sweden)

    Cesar Orsini

    2016-05-01

    Full Text Available Purpose: This study aimed at conducting a systematic review in health professions education of determinants, mediators and outcomes of students’ motivation to engage in academic activities based on the self-determination theory’s perspective. Methods: A search was conducted across databases (MEDLINE, CINHAL, EMBASE, PsycINFO, and ERIC databases, hand-search of relevant journals, grey literature, and published research profile of key authors. Quantitative and qualitative studies were included if they reported research in health professions education focused on determinants, mediators, and/or outcomes of motivation from the self-determination and if meeting the quality criteria. Results: A total of 17 studies met the inclusion and quality criteria. Articles retrieved came from diverse locations and mainly from medical education and to a lesser extent from psychology and dental education. Intrapersonal (gender and personality traits and interpersonal determinants (academic conditions and lifestyle, qualitative method of selection, feedback, and an autonomy supportive learning climate have been reported to have a positive influence on students’ motivation to engage in academic activities. No studies were found that tested mediation effects between determinants and students’ motivation. In turn, students’ self-determined motivation has been found to be positively associated with different cognitive, affective, and behavioural outcomes. Conclusion: This study has found that generally, motivation could be enhanced by changes in the educational environment and by an early detection of students’ characteristics. Doing so may support future health practitioners’ self-determined motivation and positively influence how they process information and their emotions and how they approach their learning activities.

  15. Determinants and outcomes of motivation in health professions education: a systematic review based on self-determination theory

    Science.gov (United States)

    2016-01-01

    Purpose: This study aimed at conducting a systematic review in health professions education of determinants, mediators and outcomes of students’ motivation to engage in academic activities based on the self-determination theory’s perspective. Methods: A search was conducted across databases (MEDLINE, CINHAL, EMBASE, PsycINFO, and ERIC databases), hand-search of relevant journals, grey literature, and published research profile of key authors. Quantitative and qualitative studies were included if they reported research in health professions education focused on determinants, mediators, and/or outcomes of motivation from the self-determination and if meeting the quality criteria. Results: A total of 17 studies met the inclusion and quality criteria. Articles retrieved came from diverse locations and mainly from medical education and to a lesser extent from psychology and dental education. Intrapersonal (gender and personality traits) and interpersonal determinants (academic conditions and lifestyle, qualitative method of selection, feedback, and an autonomy supportive learning climate) have been reported to have a positive influence on students’ motivation to engage in academic activities. No studies were found that tested mediation effects between determinants and students’ motivation. In turn, students’ self-determined motivation has been found to be positively associated with different cognitive, affective, and behavioural outcomes. Conclusion: This study has found that generally, motivation could be enhanced by changes in the educational environment and by an early detection of students’ characteristics. Doing so may support future health practitioners’ self-determined motivation and positively influence how they process information and their emotions and how they approach their learning activities. PMID:27134006

  16. Predicted fuel consumption in the Burnup model: sensitivity to four user inputs

    Science.gov (United States)

    D. C. Lutes

    2013-01-01

    Fuelbeds consist of a number of combustible components that are consumed during a fire, including duff, litter, vegetation (herbs, shrub, foliage, and branches) and down dead woody material (DWM). Combustion of DWM during a fire has a well-documented role in determining fire effects and fire behavior impacts such as emissions (Sandberg and others 2002), vegetative...

  17. 12 CFR 652.90 - How to report your risk-based capital determination.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false How to report your risk-based capital... AGRICULTURAL MORTGAGE CORPORATION FUNDING AND FISCAL AFFAIRS Risk-Based Capital Requirements § 652.90 How to report your risk-based capital determination. (a) Your risk-based capital report must contain at least...

  18. Separation of metallic residues from the dissolution of a high-burnup BWR fuel using nitrogen trifluoride

    Energy Technology Data Exchange (ETDEWEB)

    McNamara, Bruce K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Soderquist, Chuck Z. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, Frances N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mausolf, Edward J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Scheele, Randall D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-03-23

    Nitrogen trifluoride (NF3) was used to fluorinate the metallic residue from the dissolution of a high burnup, boiling water reactor fuel (~70 MWd/kgU). The metallic residue included the noble metal phase (containing ruthenium, rhodium, palladium, technetium, and molybdenum), and smaller amounts of zirconium, selenium, tellurium, and silver. Exposing the noble metal phase to 10% NF3 in argon between 400 and 550°C, removed molybdenum and technetium near 400°C as their volatile fluorides, and ruthenium near 500C as its volatile fluoride. The events were thermally and temporally distinct and the conditions specified are a recipe to separate these transition metals from each other and from the noble metal phase nonvolatile residue. Depletion of the volatile fluorides resulted in substantial exothermicity. Thermal excursion behavior was recorded under non-adiabatic, isothermal conditions that typically minimize heat release. Physical characterization of the metallic noble phase and its thermal behavior are consistent with high kinetic velocity reactions encouraged by the nanoparticulate phase or perhaps catalytic influences of the mixed platinum metals with nearly pure phase structure. Post-fluorination, only two phases were present in the residual nonvolatile fraction. These were identified as a nano-crystalline, metallic palladium cubic phase and a hexagonal rhodium trifluoride (RhF3) phase. The two phases were distinct as the sub-µm crystallites of metallic palladium were in contrast to the RhF3 phase, which grew from the parent nano-crystalline noble-metal phase during fluorination, to acicular crystals exceeding 20-µm in length.

  19. Autonomous Sub-Pixel Satellite Track Endpoint Determination for Space Based Images

    Energy Technology Data Exchange (ETDEWEB)

    Simms, L M

    2011-03-07

    An algorithm for determining satellite track endpoints with sub-pixel resolution in spaced-based images is presented. The algorithm allows for significant curvature in the imaged track due to rotation of the spacecraft capturing the image. The motivation behind the subpixel endpoint determination is first presented, followed by a description of the methodology used. Results from running the algorithm on real ground-based and simulated spaced-based images are shown to highlight its effectiveness.

  20. Experiment Safety Assurance Package for the 40- to 52-GWd/MT Burnup Phase of Mixed Oxide Fuel Irradiation in Small I-hole Positions in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    S. T. Khericha; R. C. Pedersen

    2003-09-01

    This experiment safety assurance package (ESAP) is a revision of the last mixed uranium and plutonium oxide (MOX) ESAP issued in June 2002). The purpose of this revision is to provide a basis to continue irradiation up to 52 GWd/MT burnup [as predicted by MCNP (Monte Carlo N-Particle) transport code The last ESAP provided basis for irradiation, at a linear heat generation rate (LHGR) no greater than 9 kW/ft, of the highest burnup capsule assembly to 50 GWd/MT. This ESAP extends the basis for irradiation, at a LHGR no greater than 5 kW/ft, of the highest burnup capsule assembly from 50 to 52 GWd/MT.

  1. 78 FR 9938 - Ethyl Alcohol for Fuel Use: Determination of the Base Quantity of Imports

    Science.gov (United States)

    2013-02-12

    ... COMMISSION Ethyl Alcohol for Fuel Use: Determination of the Base Quantity of Imports AGENCY: United States... is equal to 7 percent of the U.S. domestic market for fuel ethyl alcohol during the 12-month period...'' of imports of fuel ethyl alcohol, and the Commission transmitted it determinations to the U.S...

  2. Determination of fission gas yields from isotope ratios

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg

    1983-01-01

    This paper describes a method of calculating the actual fission yield of Kr and Xe in nuclear fuel including the effect of neutron capture reactions and decay. The bases for this calculation are the cumulative yields (ref. 1) of Kr and Xe isotopes (or pairs of isotopes) which are unaffected...... by neutron capture reactions, and measured Kr and Xe isotope ratios. Also the burnup contribution from the different fissile heavy isotopes must be known in order to get accurate fission gas yields....

  3. Modeling of PWR fuel at extended burnup; Estudo de modelos para o comportamento a altas queimas de varetas combustiveis de reatores a agua leve pressurizada

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Raphael Mejias

    2016-11-01

    This work studies the modifications implemented over successive versions in the empirical models of the computer program FRAPCON used to simulate the steady state irradiation performance of Pressurized Water Reactor (PWR) fuel rods under high burnup condition. In the study, the empirical models present in FRAPCON official documentation were analyzed. A literature study was conducted on the effects of high burnup in nuclear fuels and to improve the understanding of the models used by FRAPCON program in these conditions. A steady state fuel performance analysis was conducted for a typical PWR fuel rod using FRAPCON program versions 3.3, 3.4, and 3.5. The results presented by the different versions of the program were compared in order to verify the impact of model changes in the output parameters of the program. It was observed that the changes brought significant differences in the results of the fuel rod thermal and mechanical parameters, especially when they evolved from FRAPCON-3.3 version to FRAPCON-3.5 version. Lower temperatures, lower cladding stress and strain, lower cladding oxide layer thickness were obtained in the fuel rod analyzed with the FRAPCON-3.5 version. (author)

  4. Evaluation of PCR-based approach for serotype determination of Streptococcus pneumoniae.

    Science.gov (United States)

    Shakrin, N N S M; Balasubramaniam, S D; Yusof, H A; Mastuki, M F; Masri, S N; Taib, N M; Nordin, S A; Jamal, F; Clarke, S C; Desa, M N M

    2013-06-01

    Determination of Streptococcus pneumoniae serotypes is essential for epidemiological surveillance. Therefore accurate, reliable and cost effective serotyping method is crucial. In this study, we determined the serotypes of 41 pneumococcal isolates recovered from human anterior nares by multiplex Polymerase Chain Reaction (PCR) utilizing published primers. The data was then compared with conventional serology using latex agglutination (LA) and the Quellung reaction. Based on the PCR-approach, 8 different serogroups/serotypes were detected with one isolate classified as non-typeable (cpsA-negative). In reference to the serology-based data, the results were in agreement except for one isolate. For the latter isolate, the LA and Quellung tests failed to show a reaction but the PCR-approach and sequencing identified the isolate as serogroup 15B/C. Based on this experimental setting, we found that the PCR-approach for pneumococcal serotypes determination is reliable to serve as the alternative for determining the pneumococcal serotyping.

  5. Determining certain geometrical characteristics of metallic engineering structures based on their shift resistance

    Energy Technology Data Exchange (ETDEWEB)

    Kvyatkovskiy, G.I.; Babyuk, I.S.; Bondarev, V.I.; Kirillov, S.A.; Kuzmenko, E.D.

    1983-01-01

    The possibility of determining the depth of submersion in the earth of metallic engineering structures based on their shift resistance is justified. The theoretical curves for real time solution of the problem based on data from field electrical measurements are shown.

  6. Determinants of Web-based CSR Disclosure in the Food Industry

    OpenAIRE

    Sommer, Florian; Klink, Jeanette; Senkl, Daniela; Hartmann, Monika

    2015-01-01

    Purpose –Web-based CSR disclosure provides a variety of advantages for firms. Determining factors for web-based CSR disclosure have been analyzed in several papers. However, only limited research has been conducted on both, the food industry and small and midsized enterprises. This paper is one contribution to fill this gap as we investigate web-based CSR communication of food processors including SME.Design/methodology/approach – We analyzed corporate communication on the website...

  7. Real-Time GNSS-Based Attitude Determination in the Measurement Domain.

    Science.gov (United States)

    Zhao, Lin; Li, Na; Li, Liang; Zhang, Yi; Cheng, Chun

    2017-02-05

    A multi-antenna-based GNSS receiver is capable of providing high-precision and drift-free attitude solution. Carrier phase measurements need be utilized to achieve high-precision attitude. The traditional attitude determination methods in the measurement domain and the position domain resolve the attitude and the ambiguity sequentially. The redundant measurements from multiple baselines have not been fully utilized to enhance the reliability of attitude determination. A multi-baseline-based attitude determination method in the measurement domain is proposed to estimate the attitude parameters and the ambiguity simultaneously. Meanwhile, the redundancy of attitude resolution has also been increased so that the reliability of ambiguity resolution and attitude determination can be enhanced. Moreover, in order to further improve the reliability of attitude determination, we propose a partial ambiguity resolution method based on the proposed attitude determination model. The static and kinematic experiments were conducted to verify the performance of the proposed method. When compared with the traditional attitude determination methods, the static experimental results show that the proposed method can improve the accuracy by at least 0.03° and enhance the continuity by 18%, at most. The kinematic result has shown that the proposed method can obtain an optimal balance between accuracy and reliability performance.

  8. Expert Knowledge-Based Automatic Sleep Stage Determination by Multi-Valued Decision Making Method

    Science.gov (United States)

    Wang, Bei; Sugi, Takenao; Kawana, Fusae; Wang, Xingyu; Nakamura, Masatoshi

    In this study, an expert knowledge-based automatic sleep stage determination system working on a multi-valued decision making method is developed. Visual inspection by a qualified clinician is adopted to obtain the expert knowledge database. The expert knowledge database consists of probability density functions of parameters for various sleep stages. Sleep stages are determined automatically according to the conditional probability. Totally, four subjects were participated. The automatic sleep stage determination results showed close agreements with the visual inspection on sleep stages of awake, REM (rapid eye movement), light sleep and deep sleep. The constructed expert knowledge database reflects the distributions of characteristic parameters which can be adaptive to variable sleep data in hospitals. The developed automatic determination technique based on expert knowledge of visual inspection can be an assistant tool enabling further inspection of sleep disorder cases for clinical practice.

  9. Determining the Future Value of Money through Alternative Methods Based on Forecast Cash Flows

    Directory of Open Access Journals (Sweden)

    Gheorghe NEGOESCU

    2014-12-01

    Full Text Available The future value of money is an important instrument used in the determination of enterprise value as current assets correction. In the current literature there are various variants for calculating this correction. The National Association of Authorized Romanian Assessors –NAARA (ANEVAR in original approved some of these methods. In this paper I propose to develop a study of determining the future value of money through alternative methods based on forecast cash flows, a study which will be the main issues of determining the current assets correction for obtaining the adjusted net asset value and the global value of the enterprise.

  10. Rapid and Sensitive Determination of Lipid Oxidation Using the Reagent Kit Based on Spectrophotometry (FOODLABfat System)

    OpenAIRE

    Kwon, Chang Woo; Park, Kyung-Min; Park, Jeong Woong; Lee, JaeHwan; Choi, Seung Jun; Chang, Pahn-Shick

    2016-01-01

    The reliability and availability of FOODLABfat system for determining acid value (AV) and peroxide value (POV) were assessed during the hydrolytic rancidification and lipid oxidation of edible oils. This reagent kit based on spectrophotometry was compared to the official methods (ISO 660 and 3960 protocols) based on manual titration employing the standard mixture for the simulated oxidation models and edible oils during the thermally induced oxidation at 180°C. The linear regression line of s...

  11. DETERMINANTS OF SYARI'AH BASED FINANCING AND ITS CONTRIBUTION FOR SMEs DEVELOPMENT

    OpenAIRE

    Sakhowi, Akhmad; Chalimah, Chalimah

    2016-01-01

    This study examines the factors that affect the volume of Shariah-based financing for results and its contribution to the SMEs development in Indonesia. The determinant of sharia-based financing covers, third party funds, financing problems (non-performing Finance), inflation rates, interest rates on working capital loans, investment credit interest rate, and the gross domestic product.  This study uses secondary data sourced from Indonesian Banking statistics published by Bank Indonesia with...

  12. Innovative and rapid procedure for 4-hydroxyproline determination in meat-based foods.

    Science.gov (United States)

    Messia, Maria Cristina; Marconi, Emanuele

    2012-01-01

    This report describes a rapid and innovative microwave procedure for protein hydrolysis coupled with high performance anion exchange chromatography and pulsed amperometric detection (HPAEC-PAD) to quantify the amino acid 4-hydroxyproline in meat and meat-based products. This innovative approach was successfully applied to determine collagen content (4-hydroxyproline × 8) as the index quality of meat material used in the preparation of typical meat-based foods.

  13. Maintenance of polygenic sex determination in a fluctuating environment: an individual-based model.

    Science.gov (United States)

    Bateman, A W; Anholt, B R

    2017-05-01

    R. A. Fisher predicted that individuals should invest equally in offspring of both sexes, and that the proportion of males and females produced (the primary sex ratio) should evolve towards 1:1 when unconstrained. For many species, sex determination is dependent on sex chromosomes, creating a strong tendency for balanced sex ratios, but in other cases, multiple autosomal genes interact to determine sex. In such cases, the maintenance of multiple sex-determining alleles at multiple loci and the consequent among-family variability in sex ratios presents a puzzle, as theory predicts that such systems should be unstable. Theory also predicts that environmental influences on sex can complicate outcomes of genetic sex determination, and that population structure may play a role. Tigriopus californicus, a copepod that lives in splash-pool metapopulations and exhibits polygenic and environment-dependent sex determination, presents a test case for relevant theory. We use this species as a model for parameterizing an individual-based simulation to investigate conditions that could maintain polygenic sex determination. We find that metapopulation structure can delay the degradation of polygenic sex determination and that periods of alternating frequency-dependent selection, imposed by seasonal fluctuations in environmental conditions, can maintain polygenic sex determination indefinitely. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  14. Seamline Determination Based on PKGC Segmentation for Remote Sensing Image Mosaicking.

    Science.gov (United States)

    Dong, Qiang; Liu, Jinghong

    2017-07-27

    This paper presents a novel method of seamline determination for remote sensing image mosaicking. A two-level optimization strategy is applied to determine the seamline. Object-level optimization is executed firstly. Background regions (BRs) and obvious regions (ORs) are extracted based on the results of parametric kernel graph cuts (PKGC) segmentation. The global cost map which consists of color difference, a multi-scale morphological gradient (MSMG) constraint, and texture difference is weighted by BRs. Finally, the seamline is determined in the weighted cost from the start point to the end point. Dijkstra's shortest path algorithm is adopted for pixel-level optimization to determine the positions of seamline. Meanwhile, a new seamline optimization strategy is proposed for image mosaicking with multi-image overlapping regions. The experimental results show the better performance than the conventional method based on mean-shift segmentation. Seamlines based on the proposed method bypass the obvious objects and take less time in execution. This new method is efficient and superior for seamline determination in remote sensing image mosaicking.

  15. Reducing Violence in Non-Controlling Ways: A Change Program Based on Self Determination Theory

    Science.gov (United States)

    Assor, Avi; Feinberg, Ofra; Kanat-Maymon, Yaniv; Kaplan, Haya

    2018-01-01

    This paper presents and examines the first school change program focusing on violence and caring based on self-determination theory (Deci & Ryan, 2012). The program aimed at promoting teachers' capacity to cope with violence and enhance caring without becoming more controlling. Comparisons of the effects of a 22-month-long program in three…

  16. Bismuth Modified Carbon-Based Electrodes for the Determination of Selected Neonicotinoid Insecticides

    Directory of Open Access Journals (Sweden)

    Marko Rodić

    2011-05-01

    Full Text Available Two types of bismuth modified electrodes, a bismuth-film modified glassy carbon (BiF-GCE and a bismuth bulk modified carbon paste, were applied for the determination of selected nitroguanidine neonicotinoid insecticides. The method based on an ex situ prepared BiF-GCE operated in the differential pulse voltammetric (DPV mode was applied to determine clothianidin in the concentration range from 2.5 to 23 μg cm−3 with a relative standard deviation (RSD not exceeding 1.5%. The tricresyl phosphate-based carbon paste electrodes (TCP-CPEs, bulk modified with 5 and 20 w/w% of bismuth, showed a different analytical performance in the determination of imidacloprid, regarding the peak shape, potential window, and noise level. The TCP-CPE with 5% Bi was advantageous, and the developed DPV method based on it allowed the determination in the concentration range from 1.7 to 60 μg cm−3 with an RSD of 2.4%. To get a deeper insight into the morphology of the bismuth-based sensor surfaces, scanning electron microscopic measurements were performed of both the surface film and the bulk modified electrodes.

  17. Determination of the smoke-plume heights and their dynamics with ground-based scanning LIDAR

    Science.gov (United States)

    V. Kovalev; A. Petkov; C. Wold; S. Urbanski; W. M. Hao

    2015-01-01

    Lidar-data processing techniques are analyzed, which allow determining smoke-plume heights and their dynamics and can be helpful for the improvement of smoke dispersion and air quality models. The data processing algorithms considered in the paper are based on the analysis of two alternative characteristics related to the smoke dispersion process: the regularized...

  18. Use of NMR Imaging to Determine the Diffusion Coefficient of Water in Bio-based Hydrogels

    Science.gov (United States)

    The diffusion of liquid in a hydrogel material is a fundamental property which must be controlled in order to create effective delivery systems for the agricultural and pharmaceutical industries. NMR spectroscopy has been used to determine the diffusion of water and deuterium oxide in a bio-based h...

  19. Determination of Trace Elements in Nickel Base Gas Turbine Parts by Atomic Absorption Spectrophotometry.

    Science.gov (United States)

    An investigation is described to ascertain whether or not atomic absorption spectrophotometry could be used to determine the concentration of trace ... elements such as silver (Ag), bismuth (Bi), cadmium (Cd), and lead (Pb) in nickel base alloys such as IN100, B1900 and 713C, without interference from

  20. A density based segmentation method to determine the coordination number of a particulate system

    NARCIS (Netherlands)

    Nguyen, Thanh T.; Tran, Thanh N.; Willemsz, Tofan A.; Frijlink, Henderik W.; Ervasti, Tuomas; Ketolainen, Jarkko; Maarschalk, Kees van der Voort

    2011-01-01

    The coordination number is an important parameter for understanding the particulate systems, especially when agglomerated particles are present. However, experimental determination of the coordination number is not trivial. In this study, we describe a 3D classification method, which is based on the

  1. Determining the Optical Properties of Two-Layer Turbid Materials Based on Spatially Resolved Diffuse Reflectance

    Science.gov (United States)

    Hyperspectral imaging-based spatially resolved technique is useful for determining the optical properties of fruits and food products that are homogeneous. To better characterize fruit properties and quality attributes, it is necessary to consider fruit to be composed of two homogeneous layers, i.e....

  2. Normal values and determinants of circadian urine production in older men : A population based study

    NARCIS (Netherlands)

    Blanker, M. H.; Bernsen, R. M.; Bosch, J. L. Ruud; Thomas, S.; Groeneveld, F. P.; Prins, A.; Bohnen, A. M.

    2002-01-01

    PURPOSE: We evaluated circadian urine production and its determinants in a large population based sample of older men. MATERIALS AND METHODS: We collected data on 1,688 men 50 to 78 years old, without radical prostatectomy, prostate or bladder cancer, neurogenic bladder disease or negative advice

  3. Two complementary Microflown based methods to determine the reflection coefficient in situ

    NARCIS (Netherlands)

    Bree, H.E. de; Tijs, E.; Basten, T.G.H.

    2006-01-01

    Two complementary methods have been developed that are capable to determine the reflection coefficient of acoustic absorbing materials in situ. The methods are compared with a measurement in the Kundt's tube. The first method is based on the measurement of the surface impedance [1], [2], [3]. Here a

  4. Biosensors based on enzyme field-effect transistors for determination of some substrates and inhibitors.

    Science.gov (United States)

    Dzyadevych, Sergei V; Soldatkin, Alexey P; Korpan, Yaroslav I; Arkhypova, Valentyna N; El'skaya, Anna V; Chovelon, Jean-Marc; Martelet, Claude; Jaffrezic-Renault, Nicole

    2003-10-01

    This paper is a review of the authors' publications concerning the development of biosensors based on enzyme field-effect transistors (ENFETs) for direct substrates or inhibitors analysis. Such biosensors were designed by using immobilised enzymes and ion-selective field-effect transistors (ISFETs). Highly specific, sensitive, simple, fast and cheap determination of different substances renders them as promising tools in medicine, biotechnology, environmental control, agriculture and the food industry. The biosensors based on ENFETs and direct enzyme analysis for determination of concentrations of different substrates (glucose, urea, penicillin, formaldehyde, creatinine, etc.) have been developed and their laboratory prototypes were fabricated. Improvement of the analytical characteristics of such biosensors may be achieved by using a differential mode of measurement, working solutions with different buffer concentrations and specific agents, negatively or positively charged additional membranes, or genetically modified enzymes. These approaches allow one to decrease the effect of the buffer capacity influence on the sensor response in an aim to increase the sensitivity of the biosensors and to extend their dynamic ranges. Biosensors for the determination of concentrations of different toxic substances (organophosphorous pesticides, heavy metal ions, hypochlorite, glycoalkaloids, etc.) were designed on the basis of reversible and/or irreversible enzyme inhibition effect(s). The conception of an enzymatic multibiosensor for the determination of different toxic substances based on the enzyme inhibition effect is also described. We will discuss the respective advantages and disadvantages of biosensors based on the ENFETs developed and also demonstrate their practical application.

  5. Beyond the Central Dogma: Model-Based Learning of How Genes Determine Phenotypes

    Science.gov (United States)

    Reinagel, Adam; Speth, Elena Bray

    2016-01-01

    In an introductory biology course, we implemented a learner-centered, model-based pedagogy that frequently engaged students in building conceptual models to explain how genes determine phenotypes. Model-building tasks were incorporated within case studies and aimed at eliciting students' understanding of 1) the origin of variation in a population…

  6. Determination of Peroxide-Based Explosives Using Liquid Chromatography with On-Line Infrared Detection

    NARCIS (Netherlands)

    Schulte-Ladbeck, Rasmus; Edelmann, Andrea; Quintas, Guillermo; Lendl, Bernhard; Karst, U.

    2006-01-01

    A nondestructive analytical method for peroxide-based explosives determination in solid samples is described. Reversed-phase high-performance liquid chromatography in combination with on-line Fourier transform infrared (FT-IR) detection is used for the analysis of triacetonetriperoxide (TATP) and

  7. A model for determining condition-based maintenance policies for deteriorating multi-component systems

    NARCIS (Netherlands)

    Hontelez, J.A.M.; Wijnmalen, D.J.D.

    1993-01-01

    We discuss a method to determine strategies for preventive maintenance of systems consisting of gradually deteriorating components. A model has been developed to compute not only the range of conditions inducing a repair action, but also inspection moments based on the last known condition value so

  8. Determination of disk diffusion susceptibility testing interpretive criteria using model-based analysis: development and implementation.

    Science.gov (United States)

    DePalma, Glen; Turnidge, John; Craig, Bruce A

    2017-02-01

    The determination of diffusion test breakpoints has become a challenging issue due to the increasing resistance of microorganisms to antibiotics. Currently, the most commonly-used method for determining these breakpoints is the modified error-rate bounded method. Its use has remained widespread despite the introduction of several model-based methods that have been shown superior in terms of precision and accuracy. However, the computational complexities associated with these new approaches has been a significant barrier for clinicians. To remedy this, we developed and examine the utility of a free online software package designed for the determination of diffusion test breakpoints: dBETS (diffusion Breakpoint Estimation Testing Software). This software package allows clinicians to easily analyze data from susceptibility experiments through visualization, error-rate bounded, and model-based approaches. We analyze four publicly available data sets from the Clinical and Laboratory Standards Institute using dBETS. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. A novel biosensor based on glucose oxidase for activity determination of α - amylase.

    Science.gov (United States)

    Altug, Cagrı; Mengulluoglu, Umut; Kurt, Elif; Kaya, Secil; Dinckaya, Erhan

    2011-10-01

    A glucose oxidase-based biosensor was developed for the determination of α-amylase activity. The determination method is based on monitoring the decrease in dissolved oxygen concentration related to the starch concentration, for which starch gives a reaction with α-amylase. Optimization parameters, including glucose oxidase amount, gelatin amount, and glutaraldehyde percentage for cross-linking, were investigated. The effects of pH, buffer system, and temperature on the biosensor system were also investigated. The biosensor had a linear relation to α-amylase activity and good measurement correlation between 0.66 and 9.83 U/ml. In sample analysis studies, α-amylase activity in baker's yeast was determined by the biosensor.

  10. ADMINISTRATOR’S ROLE IN PERFORMANCE BASED REWARD AS A DETERMINANT OF EMPLOYEE OUTCOMES

    Directory of Open Access Journals (Sweden)

    Azman ISMAIL

    2015-06-01

    Full Text Available According to the recent literature pertaining on workplace compensation program, administrators often play two important roles in planning and implementing performance based reward: communication and performance appraisal. Recent studies in this field highlights that the ability of administrators to appropriately communicate pay information and appraise employee performance may have a significant impact on employee outcomes, especially job satisfaction and organizational commitment. Therefore, this study was conducted to assess the relationship between administrator’s role in performance based reward and employee outcomes using self-administered questionnaires collected from employees at a district council in Malaysia. The outcomes of the SmartPLS path model analysis showed that pay communication does not act as an important determinant of job satisfaction, but performance appraisal does act as an important determinant of job satisfaction. Conversely, both pay communication and performance appraisal act as important determinants of organizational commitment. Hence, discussion, implications and conclusion are elaborated.

  11. Position determination of spacecraft at Mars using earth-based differential tracking

    Science.gov (United States)

    Kahn, Robert D.; Folkner, William M.; Edwards, Charles D.; Vijayaraghavan, A.

    1992-01-01

    The presence of two or more landed or orbiting spacecraft at a planet provides the opportunity to perform extremely accurate earth-based navigation by simultaneously acquiring Doppler data and either Same-Beam Interferometry (SBI) or ranging data. Covariance analyses were performed to investigate the accuracy with which lander and rover positions on the surface of Mars can be determined. Simultaneous acquisition of Doppler and ranging data from a lander and rover over two or more days enables determination of all components of their relative position to under 20 m. Acquiring one hour of Doppler and SBI enables three-dimensional lander-rover relative position determination to better than 5 m. Twelve hours of Doppler and either SBI or ranging from a lander and a low circular or half synchronous circular Mars orbiter makes possible lander absolute position determination to tens of meters.

  12. Vision sensor and dual MEMS gyroscope integrated system for attitude determination on moving base

    Science.gov (United States)

    Guo, Xiaoting; Sun, Changku; Wang, Peng; Huang, Lu

    2018-01-01

    To determine the relative attitude between the objects on a moving base and the base reference system by a MEMS (Micro-Electro-Mechanical Systems) gyroscope, the motion information of the base is redundant, which must be removed from the gyroscope. Our strategy is to add an auxiliary gyroscope attached to the reference system. The master gyroscope is to sense the total motion, and the auxiliary gyroscope is to sense the motion of the moving base. By a generalized difference method, relative attitude in a non-inertial frame can be determined by dual gyroscopes. With the vision sensor suppressing accumulative drift of the MEMS gyroscope, the vision and dual MEMS gyroscope integration system is formed. Coordinate system definitions and spatial transform are executed in order to fuse inertial and visual data from different coordinate systems together. And a nonlinear filter algorithm, Cubature Kalman filter, is used to fuse slow visual data and fast inertial data together. A practical experimental setup is built up and used to validate feasibility and effectiveness of our proposed attitude determination system in the non-inertial frame on the moving base.

  13. Rapid and Sensitive Determination of Lipid Oxidation Using the Reagent Kit Based on Spectrophotometry (FOODLABfat System

    Directory of Open Access Journals (Sweden)

    Chang Woo Kwon

    2016-01-01

    Full Text Available The reliability and availability of FOODLABfat system for determining acid value (AV and peroxide value (POV were assessed during the hydrolytic rancidification and lipid oxidation of edible oils. This reagent kit based on spectrophotometry was compared to the official methods (ISO 660 and 3960 protocols based on manual titration employing the standard mixture for the simulated oxidation models and edible oils during the thermally induced oxidation at 180°C. The linear regression line of standard mixture and the significant difference of thermally oxidized time course study determined between them showed high correlations (R2=0.998 and p<0.05 in both AVs and POVs. Considering ISO protocols with a probability of human error in manual titration, the rapidness and simplicity of the reagent kit based on spectrophotometry make it a promising alternative to monitor the lipid oxidation of edible oils and lipid-containing foods.

  14. Determinants of Physical Activity Maintenance in Breast Cancer Survivors After a Community-Based Intervention.

    Science.gov (United States)

    Lee, C Ellen; Von Ah, Diane; Szuck, Beth; Lau, Yiu-Keung James

    2016-01-01

    To determine whether empirically selected and social cognitive theory-based factors, including baseline characteristics and modifiable behavioral and psychosocial factors, were determinants of physical activity (PA) maintenance in breast cancer survivors (BCSs) six months after a PA intervention.
. Single-group longitudinal study.
. The Breast Health Centre in Winnipeg, Manitoba, Canada.
. 42 survivors with stage 0-III breast cancer who completed chemotherapy and/or radiation therapy.
. The community-based PA intervention included six weekly education and practice sessions on home-based aerobic, resistance, balance, and flexibility exercises.
. The dependent variable, PA maintenance, was determined based on PA level measurement at six months postintervention. The independent variables of baseline characteristics (age, stage of cancer, and chronic musculoskeletal symptoms) and modifiable behavioral and psychosocial factors (PA level, fatigue, PA self-efficacy in overcoming barriers and performing tasks) were assessed at baseline and postintervention.
. Multivariate regression analyses revealed that baseline fatigue and chronic musculoskeletal symptoms were the only factors significantly associated with PA maintenance.
. Baseline fatigue level and chronic musculoskeletal symptoms were significant determinants of PA maintenance in breast cancer survivors who had completed a community-based PA intervention. However, other key factors were considered.
. Prior to participation in community-based PA interventions, clinicians should take into account the effects of high baseline fatigue levels and chronic musculoskeletal symptoms on potential PA maintenance, and consider additional assessments and support for BCSs to sustain their PA behavioral change.
.

  15. GNSS-based Road Charging Systems - Assessment of Vehicle Location Determination

    DEFF Research Database (Denmark)

    Zabic, Martina

    . Hence, the thesis introduces the use of system dependability of GNSS-based road charging systems. The concepts of system dependability, adapted from computer engineering, provide an effective means of managing various concerns for road charging systems within a single conceptual framework. Dependability......An increasing demand for satellite-based road charging systems is developing in Europe. Satellite-based road charging involves charging road users for their road usage by allowing the vehicles to locate themselves within a certain charge area using Global Navigation Satellite Systems (GNSS......). The research presented in this thesis deals with the performance and technological challenges of vehicle location determination within GNSS-based road charging systems. GNSS-based road charging systems may take on a number of different forms. Depending on the charging objective, these road charging systems can...

  16. General analytical procedure for determination of acidity parameters of weak acids and bases.

    Science.gov (United States)

    Pilarski, Bogusław; Kaliszan, Roman; Wyrzykowski, Dariusz; Młodzianowski, Janusz; Balińska, Agata

    2015-01-01

    The paper presents a new convenient, inexpensive, and reagent-saving general methodology for the determination of pK a values for components of the mixture of diverse chemical classes weak organic acids and bases in water solution, without the need to separate individual analytes. The data obtained from simple pH-metric microtitrations are numerically processed into reliable pK a values for each component of the mixture. Excellent agreement has been obtained between the determined pK a values and the reference literature data for compounds studied.

  17. A simple DNA based method for determination of pure Black Slavonian pigs

    OpenAIRE

    Polona Margeta; Damir Jakšić; Peter Dovč; Gordana Kralik; Vladimir Margeta

    2010-01-01

    The aim of this work was to determine the MC1R genotype of Black Slavonian pigs and to find an efficient and simple PCR-RFLP method, based on differences in MC1R genotype, to distinguish between purebred Black Slavonian pigs and their crossings with commercial pig breeds and Wild Boars. Sequencing of the MC1R exon was performed to determine the genotype of MC1R in Black Slavonian pig breed, which was shown to be MC1R*2. Digestion reactions of both PCR products representing the majority of MC1...

  18. Determination of fatty acid based lubricity improver in diesel by GC

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, Anju; Singh, Dheer; Ram Kalsi, Wadhawa; Sugumaran, Vatsala; Singh Sarpal, Amarjit; Basu, Biswajit [Indian Oil Corporation Ltd., Haryana (India). Research and Development Centre

    2009-10-15

    GC/FID has been used for the determination of a fatty acid based lubricity improver in diesel fuel. The method makes use of phase transfer catalysis for the enrichment of the lubricity improver from the diesel matrix. The use of phase transfer catalysis for the simultaneous extraction, preconcentration and derivatisation of the fatty acids enables determination of concentrations of 20 mg L{sup -1}. The method has been successfully applied to the analysis of diesel streams from various sources. The effect of the diesel matrix has also been investigated and it does not affect the recovery of the additive. (orig.)

  19. Satellite single-axis attitude determination based on Automatic Dependent Surveillance - Broadcast signals

    Science.gov (United States)

    Zhou, Kaixing; Sun, Xiucong; Huang, Hai; Wang, Xinsheng; Ren, Guangwei

    2017-10-01

    The space-based Automatic Dependent Surveillance - Broadcast (ADS-B) is a new technology for air traffic management. The satellite equipped with spaceborne ADS-B system receives the broadcast signals from aircraft and transfers the message to ground stations, so as to extend the coverage area of terrestrial-based ADS-B. In this work, a novel satellite single-axis attitude determination solution based on the ADS-B receiving system is proposed. This solution utilizes the signal-to-noise ratio (SNR) measurement of the broadcast signals from aircraft to determine the boresight orientation of the ADS-B receiving antenna fixed on the satellite. The basic principle of this solution is described. The feasibility study of this new attitude determination solution is implemented, including the link budget and the access analysis. On this basis, the nonlinear least squares estimation based on the Levenberg-Marquardt method is applied to estimate the single-axis orientation. A full digital simulation has been carried out to verify the effectiveness and performance of this solution. Finally, the corresponding results are processed and presented minutely.

  20. [An optical-fiber-sensor-based spectrophotometer for soil non-metallic nutrient determination].

    Science.gov (United States)

    He, Dong-xian; Hu, Juan-xiu; Lu, Shao-kun; He, Hou-yong

    2012-01-01

    In order to achieve rapid, convenient and efficient soil nutrient determination in soil testing and fertilizer recommendation, a portable optical-fiber-sensor-based spectrophotometer including immersed fiber sensor, flat field holographic concave grating, and diode array detector was developed for soil non-metallic nutrient determination. According to national standard of ultraviolet and visible spectrophotometer with JJG 178-2007, the wavelength accuracy and repeatability, baseline stability, transmittance accuracy and repeatability measured by the prototype instrument were satisfied with the national standard of III level; minimum spectral bandwidth, noise and excursion, and stray light were satisfied with the national standard of IV level. Significant linear relationships with slope of closing to 1 were found between the soil available nutrient contents including soil nitrate nitrogen, ammonia nitrogen, available phosphorus, available sulfur, available boron, and organic matter measured by the prototype instrument compared with that measured by two commercial single-beam-based and dual-beam-based spectrophotometers. No significant differences were revealed from the above comparison data. Therefore, the optical-fiber-sensor-based spectrophotometer can be used for rapid soil non-metallic nutrient determination with a high accuracy.

  1. Sex determination based on a thoracic vertebra and ribs evaluation using clinical chest radiography.

    Science.gov (United States)

    Tsubaki, Shun; Morishita, Junji; Usumoto, Yosuke; Sakaguchi, Kyoko; Matsunobu, Yusuke; Kawazoe, Yusuke; Okumura, Miki; Ikeda, Noriaki

    2017-07-01

    Our aim was to investigate whether sex can be determined from a combination of geometric features obtained from the 10th thoracic vertebra, 6th rib, and 7th rib. Six hundred chest radiographs (300 males and 300 females) were randomly selected to include patients of six age groups (20s, 30s, 40s, 50s, 60s, and 70s). Each group included 100 images (50 males and 50 females). A total of 14 features, including 7 lengths, 5 indices for the vertebra, and 2 types of widths for ribs, were utilized and analyzed for sex determination. Dominant features contributing to sex determination were selected by stepwise discriminant analysis after checking the variance inflation factors for multicollinearity. The accuracy of sex determination using a combination of the vertebra and ribs was evaluated from the selected features by the stepwise discriminant analysis. The accuracies in each age group were also evaluated in this study. The accuracy of sex determination based on a combination of features of the vertebra and ribs was 88.8% (533/600). This performance was superior to that of the vertebra or ribs only. Moreover, sex determination of subjects in their 20s demonstrated the highest accuracy (96.0%, 96/100). The features selected in the stepwise discriminant analysis included some features in both the vertebra and ribs. These results indicate the usefulness of combined information obtained from the vertebra and ribs for sex determination. We conclude that a combination of geometric characteristics obtained from the vertebra and ribs could be useful for determining sex. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Automated cloud base height determination from high resolution Landsat data - A Hough transform approach

    Science.gov (United States)

    Sengupta, S. K.; Berendes, T.; Welch, R. M.; Navar, M.; Wielicki, B.

    1990-01-01

    A direct method for determining the cloud base height derived from the displacement of the shadow from the cloud, and the solar azimuth and zenith angle is presented. Cumulus cloud scenes over land from Landsat MSS imagery are considered. The clouds are first matched with the corresponding shadows; the pixel distance of a reference point in the cloud is computed from the corresponding reference point in the shadow; and then the solar zenith angle is used to compute the cloud base height. Observations indicate that the cloud base height appears to be size-dependent with larger clouds generally associated with higher cloud bases and that clouds within the same size range and within the same scene region are approximately of the same height.

  3. New Computational Approaches to Determining the Astronomical Vessel Position Based on the Sumner Line

    Directory of Open Access Journals (Sweden)

    Chen Chih-Li

    2015-01-01

    Full Text Available In this paper two new approaches are developed to calculate the astronomical vessel position (AVP. Basically, determining the AVP is originated from the spherical equal altitude circles (EACs concept; therefore, based on the Sumner line's idea, which implies the trial-and-error procedure in assumption, the AVP is determined by using the two proposed approaches. One consists in taking the great circle of spherical geometry to replace the EAC to fix the AVP and the other implements the straight line of the plane geometry to replace the EAC to yield the AVP. To ensure the real AVP, both approaches choose the iteration scheme running in the assumed latitude interval to determine the final AVP. Several benchmark examples are demonstrated to show that the proposed approaches are more accurate and universal as compared with those conventional approaches used in the maritime education or practical operations.

  4. Relative Status Determination for Spacecraft Relative Motion Based on Dual Quaternion

    Directory of Open Access Journals (Sweden)

    Jun Sun

    2014-01-01

    Full Text Available For the two-satellite formation, the relative motion and attitude determination algorithm is a key component that affects the flight quality and mission efficiency. The relative status determination algorithm is proposed based on the Extended Kalman Filter (EKF and the system state optimal estimate linearization. Aiming at the relative motion of the spacecraft formation navigation problem, the spacecraft relative kinematics and dynamics model are derived from the dual quaternion in the algorithm. Then taking advantage of EKF technique, combining with the dual quaternion integrated dynamic models, considering the navigation algorithm using the fusion measurement by the gyroscope and star sensors, the relative status determination algorithm is designed. At last the simulation is done to verify the feasibility of the algorithm. The simulation results show that the EKF algorithm has faster convergence speed and higher accuracy.

  5. A Disposable Alkaline Phosphatase-Based Biosensor for Vanadium Chronoamperometric Determination

    Science.gov (United States)

    Alvarado-Gámez, Ana Lorena; Alonso-Lomillo, María Asunción; Domínguez-Renedo, Olga; Arcos-Martínez, María Julia

    2014-01-01

    A chronoamperometric method for vanadium ion determination, based on the inhibition of the enzyme alkaline phosphatase, is reported. Screen-printed carbon electrodes modified with gold nanoparticles were used as transducers for the immobilization of the enzyme. The enzymatic activity over 4-nitrophenyl phosphate sodium salt is affected by vanadium ions, which results in a decrease in the chronoamperometric current registered. The developed method has a detection limit of 0.39 ± 0.06 μM, a repeatability of 7.7% (n = 4) and a reproducibility of 8% (n = 3). A study of the possible interferences shows that the presence of Mo(VI), Cr(III), Ca(II) and W(VI), may affect vanadium determination at concentration higher than 1.0 mM. The method was successfully applied to the determination of vanadium in spiked tap water. PMID:24569772

  6. A Disposable Alkaline Phosphatase-Based Biosensor for Vanadium Chronoamperometric Determination

    Directory of Open Access Journals (Sweden)

    Ana Lorena Alvarado-Gámez

    2014-02-01

    Full Text Available A chronoamperometric method for vanadium ion determination, based on the inhibition of the enzyme alkaline phosphatase, is reported. Screen-printed carbon electrodes modified with gold nanoparticles were used as transducers for the immobilization of the enzyme. The enzymatic activity over 4-nitrophenyl phosphate sodium salt is affected by vanadium ions, which results in a decrease in the chronoamperometric current registered. The developed method has a detection limit of 0.39 ± 0.06 µM, a repeatability of 7.7% (n = 4 and a reproducibility of 8% (n = 3. A study of the possible interferences shows that the presence of Mo(VI, Cr(III, Ca(II and W(VI, may affect vanadium determination at concentration higher than 1.0 mM. The method was successfully applied to the determination of vanadium in spiked tap water.

  7. Determination of trace amount of formaldehyde base on a bromate-Malachite Green system

    Science.gov (United States)

    Tang, Yufang; Chen, Hao; Weng, Chao; Tang, Xiaohui; Zhang, Miaoling; Hu, Tao

    2015-01-01

    A novel catalytic kinetic spectrophotometric method for determination of trace amount of formaldehyde (FA) has been established, based on catalytic effect of trace amount of FA on the oxidation of Malachite Green (MG) by potassium bromate in presence of sulfuric acid medium, and was reported for the first time. The method was monitored by measuring the decrease in absorbance of MG at 617 nm and allowed a precise determination of FA in the range of 0.003-0.08 μg mL-1, with a limit of detection down to 1 ng mL-1. The relative standard deviation of 10 replicate measurements was 1.63%. The method developed was approved to be sensitive, selective and accurate, and adopted to determinate free FA in samples directly with good accuracy and reproducibility.

  8. Determination of type and concentration of DNA nitrogenous bases by Raman spectroscopy using artificial neural networks

    Science.gov (United States)

    Laptinskiy, Kirill A.; Burikov, Sergey A.; Sarmanova, Olga E.; Dolenko, Sergey A.; Dolenko, Tatiana A.

    2016-04-01

    In this article the results of solution of two-parametrical inverse problems of laser Raman spectroscopy of identification and determination of concentration of DNA nitrogenous bases in two-component solutions are presented. Elaboration of methods of control of reactions with DNA strands in remote real-time mode is necessary for solution of one of the basic problems of creation of biocomputers - increase of reliability of molecular DNA-computations. The comparative analysis of two used methods of solution of stated problems has demonstrated convincing advantages of technique of artificial neural networks. Use of artificial neural networks allowed to reach the accuracy of determination of concentration of each base in two-component solutions 0.2-0.3 g/l.

  9. Determination of isocyanate groups in the organic intermediates by reaction-based headspace gas chromatography.

    Science.gov (United States)

    Xie, Wei-Qi; Chai, Xin-Sheng

    2016-10-14

    This work reports on a novel method for the determination of isocyanate groups in the related organic intermediates by a reaction-based headspace gas chromatography. The method is based on measuring the CO2 formed from the reaction between the isocyanate groups in the organic intermediates and water in a closed headspace sample vial at 45°C for 20min. The results showed that the method has a good precision and accuracy, in which the relative standard deviation in the repeatability measurement was 5.26%, and the relative differences between the data obtained by the HS-GC method and the reference back-titration method were within 9.42%. The present method is simple and efficient and is particularly suitable to be used for determining the isocyanate groups in the batch sample analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. INEMO: Distributed RF-Based Indoor Location Determination with Confidence Indicator

    Science.gov (United States)

    Li, Hongbin; Shen, Xingfa; Zhao, Jun; Wang, Zhi; Sun, Youxian

    2007-12-01

    Using radio signal strength (RSS) in sensor networks localization is an attractive method since it is a cost-efficient method to provide range indication. In this paper, we present a two-tier distributed approach for RF-based indoor location determination. Our approach, namely, INEMO, provides positioning accuracy of room granularity and office cube granularity. A target can first give a room granularity request and the background anchor nodes cooperate to accomplish the positioning process. Anchors in the same room can give cube granularity if the target requires further accuracy. Fixed anchor nodes keep monitoring status of nearby anchors and local reference matching is used to support room separation. Furthermore, we utilize the RSS difference to infer the positioning confidence. The simulation results demonstrate the efficiency of the proposed RF-based indoor location determination.

  11. INEMO: Distributed RF-Based Indoor Location Determination with Confidence Indicator

    Directory of Open Access Journals (Sweden)

    Youxian Sun

    2007-12-01

    Full Text Available Using radio signal strength (RSS in sensor networks localization is an attractive method since it is a cost-efficient method to provide range indication. In this paper, we present a two-tier distributed approach for RF-based indoor location determination. Our approach, namely, INEMO, provides positioning accuracy of room granularity and office cube granularity. A target can first give a room granularity request and the background anchor nodes cooperate to accomplish the positioning process. Anchors in the same room can give cube granularity if the target requires further accuracy. Fixed anchor nodes keep monitoring status of nearby anchors and local reference matching is used to support room separation. Furthermore, we utilize the RSS difference to infer the positioning confidence. The simulation results demonstrate the efficiency of the proposed RF-based indoor location determination.

  12. A concept of a component based system to determine pot-plant shelf-life

    DEFF Research Database (Denmark)

    Körner, Oliver; Skou, Anne-Marie Thonning; Aaslyng, Jesper Peter Mazanti

    2006-01-01

    Plant keeping quality during shelf life is next to genetic attributes also determined by plant treatment. This is attributed to inner plant quality parameters. We expect that a model including information gathered during crop cultivation could be used to predict the inner crop quality. From that......, the keeping quality of a plant after removal from the greenhouse could be estimated. A concept of a system that describes a model based knowledge system aiming at determination of the last selling date for pot plants is presented. The core of the conceptual system is a tool that can either be used...... to calculate the expected keeping quality, or it will be able to apply the system as decision support during plant cultivation. In the latter case, the model-based system can be implemented in a greenhouse climate computer. The concept contains information on climate control strategies, controlled stress...

  13. Coulometric–potentiometric determination of pKA of several organic bases in propylene carbonate

    Directory of Open Access Journals (Sweden)

    LJILJANA N. JAKSIC

    2008-06-01

    Full Text Available The pKA values of protonated triethylamine, pyridine and 2,2'-dipyridyl in propylene carbonate (PC were determined by applying the coulometric––potentiometric method and a hydrogen/palladium generator anode (H2/Pd. The investigated and reference base were titrated to 50 % with protons electrogenerated from hydrogen-saturated palladium, in the presence of sodium perchlorate as the supporting electrolyte. The half-neutralization potentials E1/2(x and E1/2(st. of the investigated and standard base, respectively, were measured using a glass–SCE pair. The obtained pKA values were compared with those reported in the literature.

  14. An electrochemical immunosensor based on pristine graphene for rapid determination of ractopamine

    Science.gov (United States)

    Qi, Shaopeng; Zhao, Bo; Zhou, Bo; Jiang, Xiaoqing

    2017-10-01

    A new electrochemical immunosensor for fast determination of ractopamine (RAC) is fabricated based on pristine graphene (PG). The PG provides a microenvironment beneficial the immobilization of RAC, promotes the electron transfer, and raises the sensitivity of the immunosensor. The free RAC in solution can be effectively measured based on the competitive immunoreaction between RAC-antibody and RAC. The calibration graph shows linearity over the concentration ranges of 0.1-10 and 10-4000 ng mL-1. The proposed immunosensor displays a satisfactory stability, selectivity, and reproducibility and has been applied to the quantificational detection of RAC in real pork samples.

  15. Impact of intervention on breastfeeding outcomes and determinants based on theory of planned behavior.

    Science.gov (United States)

    Zhu, Yu; Zhang, Zhihong; Ling, Yun; Wan, Hongwei

    2017-04-01

    Breastfeeding knowledge, attitude, subjective norm, and perceived control are significant determinants of breastfeeding, according to the theory of planned behavior (TPB). However, evidence concerning the effectiveness of the TPB-based intervention in breastfeeding promotion is sparse. Meanwhile, the changes of these determinants with time have not been examined in previous studies. To investigate the effectiveness of the TPB-based intervention program in improving exclusive breastfeeding, and the interaction of time and intervention on these determinants of breastfeeding. 285 primiparous mothers were included, with 157 mothers in the experimental group and 128 mothers in the control group. The experimental group received the TPB-based intervention program delivered during 6 weeks postpartum, while both the experimental and control groups received the standard obstetric care. Scores of breastfeeding knowledge, attitude and breastfeeding control increased with time from baseline to 6 weeks postpartum, while breastfeeding subjective norm decreased at 6 weeks both in the experimental and the control groups. Besides, scores of the four determinants were significantly higher in the experimental group than these in the control group at 3days and 6 weeks, except for breastfeeding control at 6 weeks, which resulted in the higher exclusive breastfeeding rates at 3days and 6 weeks in the experimental group than the control group. The TPB-based intervention was effective in promoting exclusive breastfeeding during 6 weeks postpartum. Future interventions are recommended to adjust intervention strategies with time, and give more focus on providing continued breastfeeding support after discharge. Copyright © 2016 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  16. Experimental determination of detonation parameters of explosives based on ammonium nitrate

    Science.gov (United States)

    Utkin, Alexander; Lavrov, Vladimir; Mochalova, Valentina

    2012-03-01

    Laser interferometer VISAR was used for investigation of the reaction zone structure and determination of detonation parameters in two different kinds of explosives based on ammonium nitrate: emulsion explosives and composite explosives with plastic binder. The influence of ammonium particles size, structure and charge diameter on detonation velocity and distribution of parameters inside of the reaction zone has been investigated for composite explosives. The effect of aging time of emulsion matrix with different storage time was found.

  17. Determination of Active Personal Space Based on Emotion when Interacting with a Service Robot

    OpenAIRE

    Sajal Chandra Banik; Ashoke Kumar Sen Gupta; M. K. Habib; Mousumi, R. N.

    2013-01-01

    This paper focuses on the determination of active personal space (APS) for a service robot based on emotional status. This is required for human-robot interaction at ease. Here, APS means the active distance (relative distance during interaction and action) between the robot and the human. APS is a function of emotion both in the human and in the robot. The other factors which are considered here are age, height, familiarity with robot, and relative motion between robot and human. According t...

  18. A New Determination Method of the Solubility Parameter of Polymer Based on AIE

    OpenAIRE

    Shan Jiang; Tian Ya Huang; Ke Min Wang; Ben Zhong Tang; Qiang Yu

    2016-01-01

    An accurate method of the fluorescence probe approach based on an aggregation-induced emission (AIE) molecule (tetraphenylethylene) for measuring the solubility parameter of the polymer is reported. This method is distinctive in that the approach can make the polymer chain conformation in solution be related to the fluorescence intensity. Since the solubility parameter of the polymer is also closely linked to its chain conformation in solution, the solubility parameter can be determined by th...

  19. A method to determine pharmacokinetic parameters based on andante constant-rate intravenous infusion

    OpenAIRE

    Yu, Rui-hong; Cao, Yong-Xiao

    2017-01-01

    On account of the disturbance from the distribution phase, the concentration-time curve of drugs cannot fully reflect the characteristics of elimination, and thus, it is difficult for present methods to obtain ideal pharmacokinetic parameters. This paper presents a method to determine pharmacokinetic parameters based on an andante constant-rate intravenous infusion. A mathematical model of the constant-rate intravenous infusion combined with the elimination of first-order kinetics was establi...

  20. [Determination of film thickness, component and content based on glass surface by using XRF spectrometry].

    Science.gov (United States)

    Mei, Yan; Ma, Mi-Xia; Nie, Zuo-Ren

    2013-12-01

    Film thickness, component and content based on glass surface were determined by using XRF technic, measure condition and instrument work condition in every layer were set and adjusted for the best measure effect for every element. Background fundamental parameter (BG-FP) method was built up. Measure results with this method were consistent with the actual preparation course and the method could fit to production application.

  1. Initial Orbit Determination Based on Propagation of Admissible Regions with Differential Algebra

    Science.gov (United States)

    2017-01-19

    Definition of the phase space vector and orbital elements . . . . . . . . . . . . . . 39 5.2 Satellite TLE...function can be validated by choosing the orbit of a real object and using the VO to generate the observation. Given the coordinates of a satellite in term...AFRL-AFOSR-UK-TR-2017-0022 Initial Orbit Determination based on propagation of admissible regions with Differential Algebra Pierluigi Di Lizia

  2. Transmission Power Determination Based on Power Amplifier Operations in Large-Scale MIMO-OFDM Systems

    OpenAIRE

    Byung Moo Lee; Youngok Kim

    2017-01-01

    This paper presents a method to determine transmission power based on power amplifier (PA) operations in order to improve the energy efficiency (EE) of a large-scale (LS) Multiple Input Multiple Output (MIMO)-OFDM system, which is a multi-carrier multiple antenna system with a large amount of transmitter (TX) antennas. Regarding the EE improvement, we propose two kinds of PA operation schemes: increasing the effective TX power (ITXP) and reducing the PA power consumption (RPC) assuming that a...

  3. The possibility of total protein concentration determination based on acoustojet phenomenon

    Science.gov (United States)

    Minin, I. V.; Minin, O. V.; Shipilov, S. E.; Zavyalova, K. V.

    2017-08-01

    It is well known that it is possible to convert sound speeds in blood into corresponding densities and total protein concentrations. In this paper we numerically study the possibilities of the blood characteristics and total protein concentrations determinations based on acoustojet phenomenon. It has been shown that the particle of the blood immersed in water allow to form acoustical field localization near the shadow surface of particle by illumination of ultrasound.

  4. Optic axis determination by fibre-based polarization-sensitive swept-source optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lu Zenghai; Kasaragod, Deepa K; Matcher, Stephen J, E-mail: z.lu@sheffield.ac.uk, E-mail: s.j.matcher@sheffield.ac.uk [Department of Materials Science and Engineering, Kroto Research Institute, University of Sheffield, North Campus, Broad Lane, Sheffield, S3 7HQ (United Kingdom)

    2011-02-21

    We describe a fibre-based variable-incidence angle (VIA) polarization-sensitive swept-source optical coherence tomography (PS-SS-OCT) system to determine the 3D optical axis of birefringent biological tissues. Single-plane VIA-PS-OCT is also explored which requires measurement of the absolute fast-axis orientation. A state-of-the-art PS-SS-OCT system with some improvements both in hardware and software was used to determine the apparent optical birefringence of equine tendon for a number of different illumination directions. Polar and azimuthal angles of cut equine tendon were produced by the VIA method and compared with the nominal values. A quarter waveplate (QWP) and equine tendon were used as test targets to validate the fast-axis measurements using the system. Polar and azimuthal angles of cut equine tendon broadly agreed with the expected values within about 8% of the nominal values. A theoretical and experimental analysis of the effect of the sample arm fibre on determination of optical axis orientation using a proposed definition based on the orientation of the eigenpolarization ellipse experimentally confirms that this algorithm only works correctly for special settings of the sample arm fibre. A proposed algorithm based on the angle between Stokes vectors on the Poincare sphere is confirmed to work for all settings of the sample arm fibre. A calibration procedure is proposed to remove the sign ambiguity of the measured orientation and was confirmed experimentally by using the QWP.

  5. Instantaneous Attitude Determination Based on Original Multi-antenna Observations Using Adaptively Robust Kalman Filtering

    Directory of Open Access Journals (Sweden)

    GAN Yu

    2015-09-01

    Full Text Available Attitude determination directly by carrier phase observation makes optimal use of observation and attitude constraints. The phase models based on misalignment angle and multiplicative quaternion error are derived. The state models for attitude estimation with and without external angular rate sensors are both erected. The attitude errors are estimated by adaptively robust filtering, in which the adaptive factors of ambiguity and attitude error are decided respectively following the idea of multi adaptive factor filtering. The factor of attitude is determined by a three-section function containing Ratio. Adaptively robust filtering makes the best use of constraint and historical information, fusing them in the calculation of float solution. As the accuracy of float solution and the structure of covariance matrix are improved greatly, the fix solution can be searched efficiently using LAMBDA (least-squares ambiguity decorrelation adjustment method merely, perfectly fulfilling the real-time requirement. Field test of a ship-based three-antenna attitude system is used to validate the proposed method. It is showed that direct attitude determination based on adaptively robust filtering has obvious advantages in efficiency and reliability.

  6. Determinants of Web-based CSR Disclosure in the Food Industry

    Directory of Open Access Journals (Sweden)

    Florian Sommer

    2015-01-01

    Full Text Available Purpose –Web-based CSR disclosure provides a variety of advantages for firms. Determining factors for web-based CSR disclosure have been analyzed in several papers. However, only limited research has been conducted on both, the food industry and small and midsized enterprises. This paper is one contribution to fill this gap as we investigate web-based CSR communication of food processors including SME.Design/methodology/approach – We analyzed corporate communication on the websites of 71 food producers from North Rhine-Westphalia, Germany using dictionary-based content analysis. Based on an ordered logit model the relationship between CSR communication and size, profitability, indebtedness and closeness to market was estimated. Economic data were obtained from the commercial database DAFNE.Findings – Our results reveal that larger firms provide relatively more CSR information than smaller firms. There was no significant relationship between CSR disclosure and profitability or indebtedness of a company and an ambiguous relationship with regard to the determinant ‘closeness to market’. Regarding the different areas of communication we found that social compared to environmental aspects were underrepresented.Practical implications – Social aspects of CSR could be used for differentiation in the market. Furthermore, as smaller firms provide relatively less information on CSR it might be worthwhile to analyze the central impediments for CSR communication for those companies.Originality/Value – This paper contributes to the ongoing discussion about firms’ CSR communication. From a convenience sample of 71 food processing firms, including SME, it provides insight regarding the determinants for CSR disclosure on firms’ websites. With the focus on the food industry and the inclusion of SME we contribute with our study to two under-researched areas.

  7. Determinants of Pro-Environmental Consumption: Multicountry Comparison Based upon Big Data Search

    Directory of Open Access Journals (Sweden)

    Donghyun Lee

    2017-01-01

    Full Text Available The Korean government has promoted a variety of environmental policies to revitalize pro-environmental consumption, and the government’s budget for this purpose has increased. However, there is a lack of quantitative data and analysis regarding the effects upon the pro-environmental consumption of education and changing public awareness of the environment. In addition, to improve pro-environmental consumption, the determinant and hindrance factors of pro-environmental consumption should be analyzed in advance. Accordingly, herein we suggest a pro-environmental consumption index that represents the condition of pro-environmental consumption based on big data queries and use the index to analyze determinants of and hindrances to pro-environmental consumption. To verify the reliability of the proposed indicator, we examine the correlation between the proposed indicator and Greendex, an existing survey-based indicator. In addition, we conduct an analysis of the determinants of pro-environmental consumption across 13 countries based upon the proposed indicator. The index is highest for Argentina and average for Korea. An analysis of the determinants shows that the levels of health expenditure, the ratio of the population aged over 65 years, and past orientation are significantly negatively related to the pro-environmental consumption index, but the level of preprimary education is significantly positively related with it. We also find that high-GDP countries have a significantly positive relationship between economy growth and pro-environmental consumption, but low-GDP countries do not have this relationship.

  8. Reliability of exclusively NOESY-based automated resonance assignment and structure determination of proteins.

    Science.gov (United States)

    Schmidt, Elena; Güntert, Peter

    2013-10-01

    Protein structure determination by NMR can in principle be speeded up both by reducing the measurement time on the NMR spectrometer and by a more efficient analysis of the spectra. Here we study the reliability of protein structure determination based on a single type of spectra, namely nuclear Overhauser effect spectroscopy (NOESY), using a fully automated procedure for the sequence-specific resonance assignment with the recently introduced FLYA algorithm, followed by combined automated NOE distance restraint assignment and structure calculation with CYANA. This NOESY-FLYA method was applied to eight proteins with 63-160 residues for which resonance assignments and solution structures had previously been determined by the Northeast Structural Genomics Consortium (NESG), and unrefined and refined NOESY data sets have been made available for the Critical Assessment of Automated Structure Determination of Proteins by NMR project. Using only peak lists from three-dimensional (13)C- or (15)N-resolved NOESY spectra as input, the FLYA algorithm yielded for the eight proteins 91-98 % correct backbone and side-chain assignments if manually refined peak lists are used, and 64-96 % correct assignments based on raw peak lists. Subsequent structure calculations with CYANA then produced structures with root-mean-square deviation (RMSD) values to the manually determined reference structures of 0.8-2.0 Å if refined peak lists are used. With raw peak lists, calculations for 4 proteins converged resulting in RMSDs to the reference structure of 0.8-2.8 Å, whereas no convergence was obtained for the four other proteins (two of which did already not converge with the correct manual resonance assignments given as input). These results show that, given high-quality experimental NOESY peak lists, the chemical shift assignments can be uncovered, without any recourse to traditional through-bond type assignment experiments, to an extent that is sufficient for calculating accurate three

  9. Determination of Indonesian palm-oil-based bioenergy sustainability indicators using fuzzy inference system

    Science.gov (United States)

    Arkeman, Y.; Rizkyanti, R. A.; Hambali, E.

    2017-05-01

    Development of Indonesian palm-oil-based bioenergy faces an international challenge regarding to sustainability issue, indicated by the establishment of standards on sustainable bioenergy. Currently, Indonesia has sustainability standards limited to palm-oil cultivation, while other standards are lacking appropriateness for Indonesian palm-oil-based bioenergy sustainability regarding to real condition in Indonesia. Thus, Indonesia requires sustainability indicators for Indonesian palm-oil-based bioenergy to gain recognition and easiness in marketing it. Determination of sustainability indicators was accomplished through three stages, which were preliminary analysis, indicator assessment (using fuzzy inference system), and system validation. Global Bioenergy partnership (GBEP) was used as the standard for the assessment because of its general for use, internationally accepted, and it contained balanced proportion between environment, economic, and social aspects. Result showed that the number of sustainability indicators using FIS method are 21 indicators. The system developed has an accuracy of 85%.

  10. Determinants of the APTT- and ETP-based APC sensitivity tests.

    Science.gov (United States)

    de Visser, M C H; van Hylckama Vlieg, A; Tans, G; Rosing, J; Dahm, A E A; Sandset, P M; Rosendaal, F R; Bertina, R M

    2005-07-01

    A reduced sensitivity for activated protein C (APC) is associated with an increased risk of venous thrombosis even in the absence of the factor (F)V Leiden mutation. This risk has been demonstrated with two APC sensitivity tests, which quantify the effects of APC on the activated partial thromboplastin time (APTT) and the endogenous thrombin potential (ETP), respectively. We examined determinants of both APC sensitivity tests in the control group of the Leiden Thrombophilia Study (LETS). Multiple linear regression analysis was performed with normalized APC-SR(APTT) or APC-SR(ETP) as dependent variable and putative determinants [levels of FII, FV, FVII, FVIII, FIX, FX, FXI, FXII, FXIII A subunit, FXIII B subunit, protein S total, protein S free, protein C, tissue factor pathway inhibitor (TFPI) total, TFPI free, antithrombin and fibrinogen] as independent variables. The major determinant of the APTT-based test was FVIII level, followed by FII level. The ETP-based test was influenced most by free protein S and free TFPI levels. In both tests FXa formation plays a major role, as the effect of FVIII and TFPI on the tests seems to be executed via FXa. The ETP-based test was also strongly influenced by oral contraceptive use, even when we adjusted for all the clotting factors listed above. This means that the effect of oral contraceptives on the ETP-based test is not fully explained by the changes of coagulation factor levels investigated in this study, and that the molecular basis of acquired APC resistance during use of oral contraceptives remains to be established.

  11. Determining the Capability Requirements for a Space-Based Optical Sensor to Determine the Trajectory of an Incoming Antisatellite Weapon

    Science.gov (United States)

    2008-03-01

    System ( XSS -11), the Near-Field Infrared Experiment (NFIRE), and the Space-based Interceptor (SBI) programs. [12] China’s ASAT test of 11 January is the...pag., April 2007. URL http://www.agi.com. AGI online Web seminar. 7. Grant H. Stokes, Ramaswamy Sridharan David Harrison, Curt von Braun and Jayant

  12. A simple DNA based method for determination of pure Black Slavonian pigs

    Directory of Open Access Journals (Sweden)

    Polona Margeta

    2010-01-01

    Full Text Available The aim of this work was to determine the MC1R genotype of Black Slavonian pigs and to find an efficient and simple PCR-RFLP method, based on differences in MC1R genotype, to distinguish between purebred Black Slavonian pigs and their crossings with commercial pig breeds and Wild Boars. Sequencing of the MC1R exon was performed to determine the genotype of MC1R in Black Slavonian pig breed, which was shown to be MC1R*2. Digestion reactions of both PCR products representing the majority of MC1R exon revealed presence of the BspHI restriction site at position 121 and absence of the AccII and CrfI restriction site at position 240, which is characteristic for the MC1R*2 genotype. A simple PCR-RFLP method, based on different coat colour MC1R gene genotypes was determined by which it is possible to detect potential crossings of autochthonous Black Slavonian pig with commercial pig breeds and also with Wild Boars.

  13. Determination of factors required to increase uptake of influenza vaccination among hospital-based healthcare workers.

    Science.gov (United States)

    Hopman, C E; Riphagen-Dalhuisen, J; Looijmans-van den Akker, I; Frijstein, G; Van der Geest-Blankert, A D J; Danhof-Pont, M B; De Jager, H J; Bos, A A; Smeets, E; De Vries, M J T; Gallee, P M M; Lenderink, A F; Hak, E

    2011-04-01

    A questionnaire study was performed in all eight University Medical Centers in The Netherlands to determine the predictors of influenza vaccination compliance in hospital-based healthcare workers (HCWs). Demographical, behavioural and organisational determinants were assessed based on behavioural and implementation models. Multivariable regression analysis was applied to assess the independent predictors for influenza vaccine uptake. Age >40 years, the presence of a chronic illness, awareness of personal risk and awareness of risk of infecting patients, trust in the effectiveness of the vaccine to reduce the risk of infecting patients, the HCWs' duty to do no harm and their duty to ensure continuity of care, finding vaccination useful despite the constant flow of visitors and having knowledge of the Health Council's advice, social influence and convenient time for vaccination were all independently associated with vaccine uptake. The accuracy of the prediction model was very high (area under the receiver operating curve: 0.95). Intervention programmes to increase influenza vaccine uptake among HCWs should target the relevant determinants identified in this study. Copyright © 2010 the Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  14. Determination of urea in milk based on N-bromosuccinimide-dichlorofluorescein postchemiluminescence method.

    Science.gov (United States)

    Nie, Fei; Wang, Na; Xu, Pan; Zheng, Jianbin

    2017-07-01

    A new postchemiluminescence (PCL) reaction was observed when urea was injected into the reaction mixture after the CL reaction of N-bromosuccinimide and dichlorofluorescein. A possible reaction mechanism was proposed based on the studies of the CL kinetic characteristics, CL spectra, fluorescence spectra, and other experiments. A new flow injection CL method for the determination of urea was established based on the PCL reaction. The relative standard deviation for the determination of urea was 1.3% (n = 11, c = 5.0 × 10-8 g/mL). The CL intensity responded linearly to the concentration of urea in the range 2.0 × 10-9-1.0 × 10-6 g/mL (r = 0.9992). The detection limit was 7 × 10-10 g/mL. The method had been applied to the determination of urea in milk with satisfactory results. Copyright © 2016. Published by Elsevier B.V.

  15. Burn-Up Determination by High Resolution Gamma Spectrometry: Spectra from Slightly-Irradiated Uranium and Plutonium between 400-830 keV

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R.S.; Ronqvist, N.

    1966-08-15

    Previously published studies of the short-cooled fission product spectra of irradiated uranium have been severely restricted by the poor energy resolution of the sodium iodide detectors used. In this report are presented fission product spectra of irradiated uranium and plutonium obtained by means of a lithium-drifted germanium detector. The resolved gamma peaks have been assigned to various fission products by correlation of measured energy and half-life values with published data. By simultaneous study of the spectra of two irradiated mixtures of plutonium and uranium, the possibility of using the activities of Ru-103 and Ru-106 as a measure of the relative fission rate in U-235 and Pu-239 has been briefly examined.

  16. Simultaneous determination of glucose and choline based on the intrinsic fluorescence of the enzymes.

    Science.gov (United States)

    Sanz-Vicente, I; Romero, J J; de Marcos, S; Ostra, M; Ubide, C; Galbán, J

    2009-07-01

    It has been possible to perform the simultaneous determination of choline and glucose using the intrinsic fluorescence of the corresponding enzyme as an analytical signal. This can be done in two ways. First, for low glucose and choline concentrations (about 0.55 mM and 0.75 microM respectively) two differentiated signals, without mutual interference, are obtained for both analytes in the same measurement. Second, when glucose and choline concentrations are higher, a new model has been designed which permits the concentrations to be accurately determined in samples containing from 0.55 mM to 3.75 mM glucose and from 0.75 microM to 11.0 microM choline; the method has been applied to simultaneous glucose and choline determinations in serum samples with good results. This method gives a better performance than multivariate calibration based on Partial Least Squares Regression. The methodology here shown could be also used for the simultaneous determination of other pairs of analytes.

  17. Kinetic spectrophotometric determination of iron based on catalytic oxidation of p-acetylarsenazo

    Directory of Open Access Journals (Sweden)

    Qing-Zhou Zhai

    2009-12-01

    Full Text Available A novel catalytic kinetic spectrophotometric method for the determination of iron is developed based on the catalytic effect of Fe(III on the oxidation reaction of p-acetylarsenazo(ASApA by potassium periodate. Maximum absorbance of the Fe(III−ASApA−KIO4 system in 8.0 × 10-3 M sulfuric acid occurs at the wavelength of 540 nm. The change in absorbance (ΔA is linearly related with the concentration of iron(III in the range of 0.10−4.0 ng/mL and fitted the equation: ΔA = 4.91 × 10-2 C (C: ng/mL + 0.017, with a regression coefficient of 0.9966 at the wavelength. The detection limit of the method is 0.031 ng/mL. The relative standard deviation of the method was from 1.34% to 1.78% for 11 replicate determinations. The standard addition recovery of the method ranged from 95.71% to 103.3%. The method was used to determine iron in the black gingili paste, oat slice, sleeve-fish silk food samples. The determined results were in agreement with those by atomic absorption spectrometry.

  18. A CMAC-based scheme for determining membership with classification of text strings.

    Science.gov (United States)

    Ma, Heng; Tseng, Ying-Chih; Chen, Lu-I

    Membership determination of text strings has been an important procedure for analyzing textual data of a tremendous amount, especially when time is a crucial factor. Bloom filter has been a well-known approach for dealing with such a problem because of its succinct structure and simple determination procedure. As determination of membership with classification is becoming increasingly desirable, parallel Bloom filters are often implemented for facilitating the additional classification requirement. The parallel Bloom filters, however, tend to produce additional false-positive errors since membership determination must be performed on each of the parallel layers. We propose a scheme based on CMAC, a neural network mapping, which only requires a single-layer calculation to simultaneously obtain information of both the membership and classification. A hash function specifically designed for text strings is also proposed. The proposed scheme could effectively reduce false-positive errors by converging the range of membership acceptance to the minimum for each class during the neural network mapping. Simulation results show that the proposed scheme committed significantly less errors than the benchmark, parallel Bloom filters, with limited and identical memory usage at different classification levels.

  19. A new method for arrival time determination of impact signal based on HHT and AIC

    Science.gov (United States)

    Liu, Mingzhou; Yang, Jiangxin; Cao, Yanpeng; Fu, Weinan; Cao, Yanlong

    2017-03-01

    Time-difference method is usually used to locate loose parts in nuclear power plant, the key to which is estimating the arrival time of impact signal caused by the crash of loose parts. However, the dispersion behavior of impact signal and the noise of nuclear power station primary circuit have negative effect on the arrival time determination. In this paper, a method of arrival time determination of impact signal based on Hilbert-Huang Transform (HHT) and Akaike Information Criterion (AIC) is proposed. Firstly, the impact signal is decomposed by Empirical Mode Decomposition (EMD). Then the instantaneous frequency of the first intrinsic mode function (IMF) is calculated, which characterizes the difference between the background noise and the impact signal. The arrival time is determined finally by AIC function. The proposed method is tested through simulation experiment which takes steel balls as the real loose parts. The deviation between the arrival time determined by proposed method and the real arrival time distributes stably under different SNRs and different sensor-to-drop point distances, mostly within the range ±0.5 ms. The proposed method is also compared with another AIC technique and a RMS approach, both of which have more dispersive distribution of deviation, quite a lot out of the range ±1 ms.

  20. New Validated Signal-averaging-based Electrocardiography Method to Determine His-ventricle Interval.

    Science.gov (United States)

    Németh, Balázs; Kellényi, Lóránd; Péterfi, István; Simor, Tamás; Ruzsa, Diána; Lőrinc, Holczer; Kiss, István; Péter, Iván; Ajtay, Zénó

    The signal-averaging (SA) technique is used to record high-resolution electrocardiograms (HRECGs) showing cardiac micropotentials. We aimed to develop a non-invasive signal-averaging-based portable bedside device to determine His-ventricle interval. After amplifying the HRECG recordings, signal duration and voltage can be measured up to four decimal precision. To validate our system, comparison of the invasively and non-invasively determined HV intervals has been performed in 20 patients. Our workgroup has developed a system capable of displaying and measuring cardiac micropotentials on storable ECG. Neither related paired-sample T-test (p=0.263) nor Wilcoxon's non-parametric signed ranks test (p=0.245) showed significant deviations of the HV intervals. Furthermore, related paired-sample T-test showed strong correlation (corr=0.910, p<0.001) between HV intervals determined by electrophysiology (EP) and non-invasive measurements. Our research group managed to assemble and validate an easy to use device capable of determining HV intervals even under ambulatory conditions. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  1. Geographical Detector-Based Identification of the Impact of Major Determinants on Aeolian Desertification Risk.

    Science.gov (United States)

    Du, Ziqiang; Xu, Xiaoming; Zhang, Hong; Wu, Zhitao; Liu, Yong

    2016-01-01

    Arid and semi-arid areas in North China are facing the challenge of a rising aeolian desertification risk (ADR) due to the intertwined effects of complex natural processes and intensified anthropogenic activities. An accurate quantitative assessment of the relationship between ADR and its determinants is beneficial for understanding the driving mechanisms of aeolian desertification and for controlling future desertification. Previous studies have failed to quantify the relative role of determinants driving ADR and have been limited in assessing their interactive impacts. In this study, a spatial variance analysis-based geographical detector methodology is used to quantify the effects of geological, physical, and human factors on the occurrence of ADR in an area characterized by mountains and hills in northern China. It is found that soil type, precipitation, and wind velocity are the major determinants of ADR, which implies that geological and physical elements (e.g., soil attribute) and climatic factors (e.g., precipitation and wind velocity) rather than human activities have played a greater role in the incidence of ADR. Particularly, the results show that the interaction of various determinants causes significant non-linearly enhanced impacts on the ADR. The findings of our study will assist local inhabitants and policy makers in developing measures for wind prevention and sand control to mitigate the effects of desertification in the region.

  2. Automated acid and base number determination of mineral-based lubricants by fourier transform infrared spectroscopy: commercial laboratory evaluation.

    Science.gov (United States)

    Winterfield, Craig; van de Voort, F R

    2014-12-01

    The Fluid Life Corporation assessed and implemented Fourier transform infrared spectroscopy (FTIR)-based methods using American Society for Testing and Materials (ASTM)-like stoichiometric reactions for determination of acid and base number for in-service mineral-based oils. The basic protocols, quality control procedures, calibration, validation, and performance of these new quantitative methods are assessed. ASTM correspondence is attained using a mixed-mode calibration, using primary reference standards to anchor the calibration, supplemented by representative sample lubricants analyzed by ASTM procedures. A partial least squares calibration is devised by combining primary acid/base reference standards and representative samples, focusing on the main spectral stoichiometric response with chemometrics assisting in accounting for matrix variability. FTIR(AN/BN) methodology is precise, accurate, and free of most interference that affects ASTM D664 and D4739 results. Extensive side-by-side operational runs produced normally distributed differences with mean differences close to zero and standard deviations of 0.18 and 0.26 mg KOH/g, respectively. Statistically, the FTIR methods are a direct match to the ASTM methods, with superior performance in terms of analytical throughput, preparation time, and solvent use. FTIR(AN/BN) analysis is a viable, significant advance for in-service lubricant analysis, providing an economic means of trending samples instead of tedious and expensive conventional ASTM(AN/BN) procedures. © 2014 Society for Laboratory Automation and Screening.

  3. Density-based energy decomposition analysis for intermolecular interactions with variationally determined intermediate state energies.

    Science.gov (United States)

    Wu, Qin; Ayers, Paul W; Zhang, Yingkai

    2009-10-28

    The first purely density-based energy decomposition analysis (EDA) for intermolecular binding is developed within the density functional theory. The most important feature of this scheme is to variationally determine the frozen density energy, based on a constrained search formalism and implemented with the Wu-Yang algorithm [Q. Wu and W. Yang, J. Chem. Phys. 118, 2498 (2003)]. This variational process dispenses with the Heitler-London antisymmetrization of wave functions used in most previous methods and calculates the electrostatic and Pauli repulsion energies together without any distortion of the frozen density, an important fact that enables a clean separation of these two terms from the relaxation (i.e., polarization and charge transfer) terms. The new EDA also employs the constrained density functional theory approach [Q. Wu and T. Van Voorhis, Phys. Rev. A 72, 24502 (2005)] to separate out charge transfer effects. Because the charge transfer energy is based on the density flow in real space, it has a small basis set dependence. Applications of this decomposition to hydrogen bonding in the water dimer and the formamide dimer show that the frozen density energy dominates the binding in these systems, consistent with the noncovalent nature of the interactions. A more detailed examination reveals how the interplay of electrostatics and the Pauli repulsion determines the distance and angular dependence of these hydrogen bonds.

  4. An Exact Method to Determine the Conductivity of Aqueous Solutions in Acid-Base Titrations

    Directory of Open Access Journals (Sweden)

    Norma Rodríguez-Laguna

    2015-01-01

    Full Text Available Several works in the literature show that it is possible to establish the analytic equations to estimate the volume V of a strong base or a strong acid (Vb and Va, resp. being added to a solution of a substance or a mix of substances during an acid-base titration, as well as the equations to estimate the first derivative of the titration plot dpH/dV, and algebraic expressions to determine the buffer β capacity with dilution βdil. This treatment allows establishing the conditions of thermodynamic equilibria for all species within a system containing a mix of species from one or from various polyacid systems. The present work shows that it is possible to determine exactly the electric conductivity of aqueous solutions for these Brønsted acid-base titrations, because the functional relation between this property and the composition of the system in equilibrium is well known; this is achieved using the equivalent conductivity λi values of each of the ions present in a given system. The model employed for the present work confirms the experimental outcomes with the H2SO4, B(OH3, CH3COOH, and H3PO4 aqueous solutions’ titration.

  5. A comparison of different estimation methods for simulation-based sample size determination in longitudinal studies

    Science.gov (United States)

    Bahçecitapar, Melike Kaya

    2017-07-01

    Determining sample size necessary for correct results is a crucial step in the design of longitudinal studies. Simulation-based statistical power calculation is a flexible approach to determine number of subjects and repeated measures of longitudinal studies especially in complex design. Several papers have provided sample size/statistical power calculations for longitudinal studies incorporating data analysis by linear mixed effects models (LMMs). In this study, different estimation methods (methods based on maximum likelihood (ML) and restricted ML) with different iterative algorithms (quasi-Newton and ridge-stabilized Newton-Raphson) in fitting LMMs to generated longitudinal data for simulation-based power calculation are compared. This study examines statistical power of F-test statistics for parameter representing difference in responses over time from two treatment groups in the LMM with a longitudinal covariate. The most common procedures in SAS, such as PROC GLIMMIX using quasi-Newton algorithm and PROC MIXED using ridge-stabilized algorithm are used for analyzing generated longitudinal data in simulation. It is seen that both procedures present similar results. Moreover, it is found that the magnitude of the parameter of interest in the model for simulations affect statistical power calculations in both procedures substantially.

  6. Acetylcholinesterase Inhibition-Based Biosensor for Aluminum(III) Chronoamperometric Determination in Aqueous Media

    Science.gov (United States)

    Barquero-Quirós, Miriam; Domínguez-Renedo, Olga; Alonso-Lomillo, Maria Asunción; Arcos-Martínez, María Julia

    2014-01-01

    A novel amperometric biosensor for the determination of Al(III) based on the inhibition of the enzyme acetylcholinesterase has been developed. The immobilization of the enzyme was performed on screen-printed carbon electrodes modified with gold nanoparticles. The oxidation signal of acetylthiocholine iodide enzyme substrate was affected by the presence of Al(III) ions leading to a decrease in the amperometric current. The developed system has a detection limit of 2.1 ± 0.1 μM for Al(III). The reproducibility of the method is 8.1% (n = 4). Main interferences include Mo(VI), W(VI) and Hg(II) ions. The developed method was successfully applied to the determination of Al(III) in spiked tap water. The analysis of a certified standard reference material was also carried out. Both results agree with the certified values considering the respective associated uncertainties. PMID:24811076

  7. [Determination of Virtual Surgery Mass Point Spring Model Parameters Based on Genetic Algorithms].

    Science.gov (United States)

    Chen, Ying; Hu, Xuyi; Zhu, Qiguang

    2015-12-01

    Mass point-spring model is one of the commonly used models in virtual surgery. However, its model parameters have no clear physical meaning, and it is hard to set the parameter conveniently. We, therefore, proposed a method based on genetic algorithm to determine the mass-spring model parameters. Computer-aided tomography (CAT) data were used to determine the mass value of the particle, and stiffness and damping coefficient were obtained by genetic algorithm. We used the difference between the reference deformation and virtual deformation as the fitness function to get the approximate optimal solution of the model parameters. Experimental results showed that this method could obtain an approximate optimal solution of spring parameters with lower cost, and could accurately reproduce the effect of the actual deformation model as well.

  8. Determination of nanograms of proteins based on the amplified resonance light scattering signals of Tichromine

    Science.gov (United States)

    Cai, Changqun; Chen, Xiaoming

    2010-03-01

    A new high-sensitivity detection of protein assay at the nanogram level is developed based on the amplified resonance light scattering signals (RLS) of Tichromine (TCM). In Walpole (NaAc-HCl) buffer (pH 4.05), TCM reacts with proteins to form large particles, which results in remarkable enhanced RLS signals characterized by three peaks at 293 nm, 399 nm and 553 nm. Mechanistic studies showed that the enhanced RLS stems from a large complex of TCM-BSA formed for the electrostatic effect between TCM and BSA. With the enhanced RLS signals at the three wavelengths, the enhanced RLS intensity is proportional to the concentration of proteins in an appropriate range. The lowest limit of determination was 7.4 ng mL -1. The proposed method was successfully applied to determine total protein in human serum samples.

  9. Spectrophotometric flow-injection determination of zinc in plant digests based on a spot test.

    Science.gov (United States)

    Dias, Ana Cristi B; Carneiro, Josiane M T; Zagatto, Elias A G

    2004-05-28

    A spot test was implemented in a flow-injection system for the spectrophotometric determination of zinc in digests of plant materials. It is based on the influence of Zn(2+) on the oxidation rate of 1-naphthylethylenediamine (NED) by hexacyanoferrate(III) under acidic conditions. In order to control the precipitate formation and to maintain the resulting suspension, a micellar medium was established by adding Triton X-100. The proposed system handles about 65 samples per hour, meaning 72mug NED and 9.0mg K(3)[Fe(CN)(6)] per determination. Baseline drift is usually 0.999, n=6) and detection limit was estimated as 0.2mgl(-1) Zn. Results are precise (R.S.D.<1%, n=10) and in agreement with flame atomic absorption spectrometry and with certified values of standard reference materials.

  10. Quantitative Determination of Total Amino Acids Based on Surface-Enhanced Raman Scattering and Ninhydrin Derivatization.

    Science.gov (United States)

    Sui, Huimin; Chen, Lei; Han, Xiao Xia; Zhang, Xiaolei; Wang, Xiaolei; Zhao, Bing

    2017-01-01

    In the present study, we propose a simple and sensitive method for the determination of total amino acids without any separation steps. The procedure described here is based on the ninhydrin derivatization reaction with amino acids, followed by surface-enhanced Raman scattering (SERS) measurements of the producing mixtures. A good linear correlation of excess ninhydrin SERS signals and the log values of the total amino acids concentrations is obtained; the detection limit of the method is 4.3 × 10-9 mol L-1. The derivatization reaction is reliable and the whole experimental procedure is very simple. The sensitivity of the proposed protocol allows quantitative analysis of total amino acids at picomole levels without any separation procedures. On the basis of the conventional ninhydrin reaction, we put forward a simple SERS method for determining the total amino acids concentrations with high sensitivity, which is a promising way for routine detection.

  11. A nanosilver-based spectrophotometry method for sensitive determination of tartrazine in food samples.

    Science.gov (United States)

    Sahraei, R; Farmany, A; Mortazavi, S S

    2013-06-01

    A new method is reported for sensitive determination of tartrazine in the food samples. The method is based on the catalytic effect of silver nanoparticle (AgNPs) on the oxidation reaction of tartrazine by potassium iodate in the acetate buffer medium. The reaction is followed spectrophotometrically by measuring the change in absorbance (ΔA) at 420 nm using a fixed time method (70 s). The reaction variables were optimised in order to achieve the highest sensitivity. The thirty six criterion detection limit was 0.3 ng/mL, and the relative standard deviation for ten replicate measurements of 30 ng/mL of tartrazine was 0.98% (n=10). The method was successfully applied to the determination of tartrazine in lemon, and papaya-flavoured gelatin, candy, and in fruit syrup. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Evaluation of EEG based determination of unconsciousness vs. loss of posture in broilers.

    Science.gov (United States)

    Benson, E R; Alphin, R L; Rankin, M K; Caputo, M P; Kinney, C A; Johnson, A L

    2012-10-01

    Evaluation of the loss of consciousness in poultry is an essential component in evaluating bird welfare under a variety of situations and applications. Many current approaches to evaluating loss of consciousness are qualitative and require observation of the bird. This study outlines a quantitative method for determining the point at which a bird loses consciousness. In this study, commercial broilers were individually anesthetized and the brain activity recorded as the bird became unconscious. A wireless EEG transmitter was surgically implanted and the bird anesthetized after a 24-48 h recovery. Each bird was monitored during treatment with isoflurane anesthesia and EEG data was evaluated using a frequency based approach. The alpha/delta (A/D) ratio and loss of posture (LOP) were used to determine the point at which the birds went unconscious. There was no statistically significant difference between time to unconsciousness as measured by A/D ratio or LOP. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Chemiluminescence determination of potassium bromate in flour based on flow injection analysis.

    Science.gov (United States)

    Yan, Zhengyu; Zhang, Zhengwei; Yu, Yan; Liu, Zhen; Chen, Jianqiu

    2016-01-01

    A novel and highly sensitive flow-injection chemiluminescence method for the determination of potassium bromate (KBrO3) has been developed. This method is based on the luminescence properties of the KBrO3-Na2SO3-quinine sulfate system in acid medium. Optimized experimental conditions and a possible mechanism were investigated. The relative chemiluminescence intensity responded linearly to the concentration of KBrO3 in the range of 7.054 × 10(-6)-1.008 × 10(-4) mol/L with a detection limit of 2.116 × 10(-6) mol/L. The relative standard deviation (RSD) at 5.0 × 10(-5) mol/L KBrO3 (n = 12) was 2.3%. The proposed method was applied successfully to the determination of KBrO3 in flour. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Acetylcholinesterase Inhibition-Based Biosensor for Aluminum(III Chronoamperometric Determination in Aqueous Media

    Directory of Open Access Journals (Sweden)

    Miriam Barquero-Quirós

    2014-05-01

    Full Text Available A novel amperometric biosensor for the determination of Al(III based on the inhibition of the enzyme acetylcholinesterase has been developed. The immobilization of the enzyme was performed on screen-printed carbon electrodes modified with gold nanoparticles. The oxidation signal of acetylthiocholine iodide enzyme substrate was affected by the presence of Al(III ions leading to a decrease in the amperometric current. The developed system has a detection limit of 2.1 ± 0.1 μM for Al(III. The reproducibility of the method is 8.1% (n = 4. Main interferences include Mo(VI, W(VI and Hg(II ions. The developed method was successfully applied to the determination of Al(III in spiked tap water . The analysis of a certified standard reference material was also carried out. Both results agree with the certified values considering the respective associated uncertainties.

  15. Determination of Work-Rest Schedules Based on Physical Workload Among Bakers in Ahvaz, Iran

    Directory of Open Access Journals (Sweden)

    Davood Afshari

    2016-09-01

    Full Text Available Background Bakery workers due to exposure to radiant heat and doing manual labor are at risk of heat-related illnesses and musculoskeletal disorders Objectives The current study aimed to determine the appropriate work-rest time interval using two indexes of wet bulb globe temperature (WBGT and relative heart rate (RHR. Methods It was an analytical and descriptive research. Heart rate of workers was continuously recorded to achieve the physiological monitoring and the obtained information was used to determine the work difficulty and physical workload. The ratio of heat stress and RHR was measured using the WBGT and polar team pro device, respectively. Work-rest schedules were detected through the heart rate reserve and heat stress indexes. The level of significance was α = 0.05. Results Physical workload based on heart rate was estimated light to moderate in bakery workers. Suitable work-rest schedule for all bakery workers according to WBGT index was 25% work-75% rest and based on heart rate reserve index in half of the workers was 50% work-50% rest, and in the other half of the bakery workers was continuous work without rest. According to Kappa test, there was no agreement between the two methods of heat stress index and heart rate reserve to determine the work-rest schedules of workers (P < 0.001. Conclusions Physical workloads on the basis of heart rate were light for all workers except the workers of Tanoury who had moderate workload. Meanwhile, determining the work-rest schedule was different using the two indexes. The heart rate reserve index represents the physiological status of individual during the work and states the ratio of physical workload more precisely.

  16. A two-stage stochastic rule-based model to determine pre-assembly buffer content

    Science.gov (United States)

    Gunay, Elif Elcin; Kula, Ufuk

    2018-01-01

    This study considers instant decision-making needs of the automobile manufactures for resequencing vehicles before final assembly (FA). We propose a rule-based two-stage stochastic model to determine the number of spare vehicles that should be kept in the pre-assembly buffer to restore the altered sequence due to paint defects and upstream department constraints. First stage of the model decides the spare vehicle quantities, where the second stage model recovers the scrambled sequence respect to pre-defined rules. The problem is solved by sample average approximation (SAA) algorithm. We conduct a numerical study to compare the solutions of heuristic model with optimal ones and provide following insights: (i) as the mismatch between paint entrance and scheduled sequence decreases, the rule-based heuristic model recovers the scrambled sequence as good as the optimal resequencing model, (ii) the rule-based model is more sensitive to the mismatch between the paint entrance and scheduled sequences for recovering the scrambled sequence, (iii) as the defect rate increases, the difference in recovery effectiveness between rule-based heuristic and optimal solutions increases, (iv) as buffer capacity increases, the recovery effectiveness of the optimization model outperforms heuristic model, (v) as expected the rule-based model holds more inventory than the optimization model.

  17. The Long-Chain Sphingoid Base of Ceramides Determines Their Propensity for Lateral Segregation.

    Science.gov (United States)

    Al Sazzad, Md Abdullah; Yasuda, Tomokazu; Murata, Michio; Slotte, J Peter

    2017-03-14

    We examined how the length of the long-chain base or the N-linked acyl chain of ceramides affected their lateral segregation in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) bilayers. Lateral segregation and ceramide-rich phase formation was ascertained by a lifetime analysis of trans-parinaric acid (tPA) fluorescence. The longer the length of the long-chain base (d16:1, d17:1, d18:1, d19:1, and d20:1 in N-palmitoyl ceramide), the less ceramide was needed for the onset of lateral segregation and ceramide-rich phase formation. A similar but much weaker trend was observed when sphingosine (d18:1)-based ceramide had N-linked acyl chains of increasing length (14:0 and 16:0-20:0 in one-carbon increments). The apparent lateral packing of the ceramide-rich phase, as determined from the longest-lifetime component of tPA fluorescence, also correlated strongly with the long-chain base length, but not as strongly with the N-acyl chain length. Finally, we compared two ceramide analogs with equal carbon numbers (d16:1/17:0 or d20:1/13:0) and observed that the analog with a longer sphingoid base segregated at lower bilayer concentrations to a ceramide-rich phase compared with the shorter sphingoid base analog. The gel phase formed by d20:1/13:0 ceramide also was more thermostable than the gel phase formed by d16:1/17:0 ceramide. 2 H NMR data for 10 mol % stearoyl ceramide in POPC also showed that the long-chain base was more ordered than the acyl chain at comparable chain positions and temperatures. We conclude that the long-chain base length of ceramide is more important than the acyl chain length in determining the lateral segregation of the ceramide-rich gel phase and intermolecular interactions therein. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  18. Determination of the orbit of the CHAMP satellite based on the laser observations

    Science.gov (United States)

    Lejba, P.

    This work presents the results of orbit determination of the CHAMP satellite from observations of 14 the best SLR stations for year 2002 All computations were based on the Earth combined gravity field model EIGEN-CG01C Reigber et al 2005 In computations was taken the orbital programme GEODYN-II created and accesibled by NASA The got RMS value of the orbit of the CHAMP satellite is better than 30 cm The obtained results show that the orbit of the CHAMP satellite is highly perturbed by the Earth s gravity field and by the atmosphere of the Earth

  19. A NEW THEORETICAL DETERMINATION OF YIELD STRESS BASED ON THE CONCEPT OF EFFICIENT AREA OF STRESS

    OpenAIRE

    A BENMOHAMMED; Ouali, M.

    2000-01-01

    This study presents a new theoretical determination of yield stress for pure mono-crystal materials based on the concept of the Efficient Area of Stress (EAS). From the atomic yield stress on the atomic surface a², given by the model of Orowan, the macroscopic yield stress is then obtained through a Scale Law of Measure (SLM) which depends only on the lattice spacing and a constant L. This relation shows that the efficient atomic dimension is a fractal dimension. The precision obtained by the...

  20. Determination of in-gel protein concentration by a ninhydrin-based method.

    Science.gov (United States)

    Kang, Sung Ung; Lubec, Gert

    2011-02-01

    Until now quantification of proteins in gel-based methods relies on the amount of protein loaded onto the gel. This does not, however, represent the amount of proteins in the gel and therefore determination of proteins within the gel is mandatory. A method to quantify proteins, both hydrophilic and hydrophobic, using in-gel digestion with proteases, subsequent acid hydrolysis and the use of the ninhydrin reaction is herein presented. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. An ARMS-based technique for sex determination of red panda (Ailurus fulgens).

    Science.gov (United States)

    Li, Yuzhi; Xu, Xiao; Zhang, Liang; Zhang, Zhihe; Shen, Fujun; Zhang, Wenping; Yue, Bisong

    2011-03-01

    Molecular sexing is a key component in the investigation of wild populations. In this study, we developed a fast, accurate and reliable amplification refractory mutation system (ARMS) technique for sex determination of red panda based on the exon 4 of the ZFX/ZFY gene. The amplicons were distinguished simply by agarose gel electrophoresis, exhibiting one fragment in females (X: 300 bp) and two in males (X: 300 bp, Y: 166 bp). Robustness of this ARMS system was confirmed by testing both 43 captive red pandas using DNA samples with known-sex and 10 wild red pandas using faecal DNA samples with unknown sex. © 2010 Blackwell Publishing Ltd.

  2. A FEM-based method to determine the complex material properties of piezoelectric disks.

    Science.gov (United States)

    Pérez, N; Carbonari, R C; Andrade, M A B; Buiochi, F; Adamowski, J C

    2014-08-01

    Numerical simulations allow modeling piezoelectric devices and ultrasonic transducers. However, the accuracy in the results is limited by the precise knowledge of the elastic, dielectric and piezoelectric properties of the piezoelectric material. To introduce the energy losses, these properties can be represented by complex numbers, where the real part of the model essentially determines the resonance frequencies and the imaginary part determines the amplitude of each resonant mode. In this work, a method based on the Finite Element Method (FEM) is modified to obtain the imaginary material properties of piezoelectric disks. The material properties are determined from the electrical impedance curve of the disk, which is measured by an impedance analyzer. The method consists in obtaining the material properties that minimize the error between experimental and numerical impedance curves over a wide range of frequencies. The proposed methodology starts with a sensitivity analysis of each parameter, determining the influence of each parameter over a set of resonant modes. Sensitivity results are used to implement a preliminary algorithm approaching the solution in order to avoid the search to be trapped into a local minimum. The method is applied to determine the material properties of a Pz27 disk sample from Ferroperm. The obtained properties are used to calculate the electrical impedance curve of the disk with a Finite Element algorithm, which is compared with the experimental electrical impedance curve. Additionally, the results were validated by comparing the numerical displacement profile with the displacements measured by a laser Doppler vibrometer. The comparison between the numerical and experimental results shows excellent agreement for both electrical impedance curve and for the displacement profile over the disk surface. The agreement between numerical and experimental displacement profiles shows that, although only the electrical impedance curve is

  3. Studies on validation possibilities for computational codes for criticality and burnup calculations of boiling water reactor fuel; Untersuchungen zu Validierungsmoeglichkeiten von Rechencodes fuer Kritikalitaets- und Abbrandrechnungen von Siedewasserreaktor-Brennstoff

    Energy Technology Data Exchange (ETDEWEB)

    Behler, Matthais; Hannstein, Volker; Kilger, Robert; Sommer, Fabian; Stuke, Maik

    2017-06-15

    The Application of the method of Burn-up Credit on Boiling Water Reactor fuel is much more complex than in the case of Pressurized Water Reactors due to the increased heterogeneity and complexity of the fuel assemblies. Strongly varying enrichments, complex fuel assembly geometries, partial length fuel rods, and strong axial variations of the moderator density make the verification of conservative irradiation conditions difficult. In this Report, it was investigated whether it is possible to take into account the burn-up in criticality analyses for systems with irradiated Boiling Water Reactor fuel on the basis of freely available experimental data and by additionally applying stochastic methods. In order to achieve this goal, existing methods for stochastic analysis were adapted and further developed in order to being applicable to the specific conditions needed in Boiling Water Reactor analysis. The aim was to gain first insight whether a workable scheme for using burn-up credit in Boiling Water Reactor applications can be derived. Due to the fact that the different relevant quantities, like e.g. moderator density and the axial power profile, are strongly correlated, the GRS-tool SUnCISTT for Monte-Carlo uncertainty quantification was used in the analysis. This tool was coupled to a simplified, consistent model for the irradiation conditions. In contrast to conventional methods, this approach allows to simultaneously analyze all involved effects.

  4. MIP-Based Sensors: Promising New Tools for Cancer Biomarker Determination

    Directory of Open Access Journals (Sweden)

    Giulia Selvolini

    2017-03-01

    Full Text Available Detecting cancer disease at an early stage is one of the most important issues for increasing the survival rate of patients. Cancer biomarker detection helps to provide a diagnosis before the disease becomes incurable in later stages. Biomarkers can also be used to evaluate the progression of therapies and surgery treatments. In recent years, molecularly imprinted polymer (MIP based sensors have been intensely investigated as promising analytical devices in several fields, including clinical analysis, offering desired portability, fast response, specificity, and low cost. The aim of this review is to provide readers with an overview on recent important achievements in MIP-based sensors coupled to various transducers (e.g., electrochemical, optical, and piezoelectric for the determination of cancer biomarkers by selected publications from 2012 to 2016.

  5. Analytical method for determining breakdown slip of an induction motor based on of five parameters

    Directory of Open Access Journals (Sweden)

    Petrović Nenad

    2014-01-01

    Full Text Available The paper proposes an explicite formula for determining the critical slip value of an induction squirel cage motor based upon five parameters. Three of these parameters - rated slip, rated and breakdown torque are known by catalogue data. Two missing parameters are the arbitrary slip between the rated and critical slip value and the corresponding torque value. These two parameters are to be experimentaly obtained. The breakdown torque value given by catalogue data is usually less accurate than the rated torque value. The proposed formula gives the possibility of analysing the error distribution of the critical slip value obtained from catalogue and measured data in comparison with the values obtained from the mechanical characteristic based on the physical parameters of an induction motor.

  6. Determination of Active Personal Space Based on Emotion when Interacting with a Service Robot

    Directory of Open Access Journals (Sweden)

    Sajal Chandra Banik

    2013-03-01

    Full Text Available This paper focuses on the determination of active personal space (APS for a service robot based on emotional status. This is required for human-robot interaction at ease. Here, APS means the active distance (relative distance during interaction and action between the robot and the human. APS is a function of emotion both in the human and in the robot. The other factors which are considered here are age, height, familiarity with robot, and relative motion between robot and human. According to these factors, the changes in APS are shown with graphs. During the experiments two robot emotions are considered: normal and angry. The causes of variation of APS based on the two modes are also explained.

  7. Mycotoxin Determination in Foods Using Advanced Sensors Based on Antibodies or Aptamers.

    Science.gov (United States)

    Xu, Lin; Zhang, Zhaowei; Zhang, Qi; Li, Peiwu

    2016-08-12

    Mycotoxin contamination threatens health and life of humans and animals throughout the food supply chains. Many of the mycotoxins have been proven to be carcinogens, teratogens and mutagens. The reliable and sensitive sensing methods are requested to monitor mycotoxin contamination. Advanced sensors based on antibodies or aptamers boast the advantages of high sensitivity and rapidity, and have been used in the mycotoxin sensing. These sensors are miniaturized, thereby lowering costs, and are applicable to high-throughput modes. In this work, the latest developments in sensing strategies for mycotoxin determination were critically discussed. Optical and electrochemical sensing modes were compared. The sensing methods for single mycotoxin or multiple mycotoxins in food samples were reviewed, along with the challenges and the future of antibody or aptamer-based sensors. This work might promote academic studies and industrial applications for mycotoxin sensing.

  8. Mycotoxin Determination in Foods Using Advanced Sensors Based on Antibodies or Aptamers

    Directory of Open Access Journals (Sweden)

    Lin Xu

    2016-08-01

    Full Text Available Mycotoxin contamination threatens health and life of humans and animals throughout the food supply chains. Many of the mycotoxins have been proven to be carcinogens, teratogens and mutagens. The reliable and sensitive sensing methods are requested to monitor mycotoxin contamination. Advanced sensors based on antibodies or aptamers boast the advantages of high sensitivity and rapidity, and have been used in the mycotoxin sensing. These sensors are miniaturized, thereby lowering costs, and are applicable to high-throughput modes. In this work, the latest developments in sensing strategies for mycotoxin determination were critically discussed. Optical and electrochemical sensing modes were compared. The sensing methods for single mycotoxin or multiple mycotoxins in food samples were reviewed, along with the challenges and the future of antibody or aptamer-based sensors. This work might promote academic studies and industrial applications for mycotoxin sensing.

  9. Improving Daytime Planetary Boundary Layer Height Determination from CALIOP: Validation Based on Ground-Based Lidar Station

    Directory of Open Access Journals (Sweden)

    Zhao Liu

    2017-01-01

    Full Text Available An integrated algorithm by combining the advantages of the wavelet covariance method and the improved maximum variance method was developed to determine the planetary boundary layer height (PBLH from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP measurements, and an aerosol fraction threshold was applied to the integrated algorithm considering the applicability of the two methods. We compared the CALIOP retrieval with the measurements of PBLH derived from nine years of ground-based Lidar synchronous observations located in Lille, north of France. The results indicate that a good correlation (R≥0.79 exists between the PBLHs derived from CALIOP and ground-based Lidar under clear sky conditions. The mean absolute differences of PBLHs are, respectively, of 206 m and 106 m before and after the removal of the aloft aerosol layer. The results under cloudy sky conditions show a lower agreement (R=0.48 in regard of the comparisons performed under clear sky conditions. Besides, the spatial correlation of PBLHs decreases with the increasing spatial distance between CALIOP footprint and Lille observation platform. Based on the above analysis, the PBLHs can be effectively derived by the integrated algorithm under clear sky conditions, while larger mean absolute difference (i.e., 527 m exists under cloudy sky conditions.

  10. Detecting determinism with improved sensitivity in time series: Rank-based nonlinear predictability score

    Science.gov (United States)

    Naro, Daniel; Rummel, Christian; Schindler, Kaspar; Andrzejak, Ralph G.

    2014-09-01

    The rank-based nonlinear predictability score was recently introduced as a test for determinism in point processes. We here adapt this measure to time series sampled from time-continuous flows. We use noisy Lorenz signals to compare this approach against a classical amplitude-based nonlinear prediction error. Both measures show an almost identical robustness against Gaussian white noise. In contrast, when the amplitude distribution of the noise has a narrower central peak and heavier tails than the normal distribution, the rank-based nonlinear predictability score outperforms the amplitude-based nonlinear prediction error. For this type of noise, the nonlinear predictability score has a higher sensitivity for deterministic structure in noisy signals. It also yields a higher statistical power in a surrogate test of the null hypothesis of linear stochastic correlated signals. We show the high relevance of this improved performance in an application to electroencephalographic (EEG) recordings from epilepsy patients. Here the nonlinear predictability score again appears of higher sensitivity to nonrandomness. Importantly, it yields an improved contrast between signals recorded from brain areas where the first ictal EEG signal changes were detected (focal EEG signals) versus signals recorded from brain areas that were not involved at seizure onset (nonfocal EEG signals).

  11. Detecting determinism with improved sensitivity in time series: rank-based nonlinear predictability score.

    Science.gov (United States)

    Naro, Daniel; Rummel, Christian; Schindler, Kaspar; Andrzejak, Ralph G

    2014-09-01

    The rank-based nonlinear predictability score was recently introduced as a test for determinism in point processes. We here adapt this measure to time series sampled from time-continuous flows. We use noisy Lorenz signals to compare this approach against a classical amplitude-based nonlinear prediction error. Both measures show an almost identical robustness against Gaussian white noise. In contrast, when the amplitude distribution of the noise has a narrower central peak and heavier tails than the normal distribution, the rank-based nonlinear predictability score outperforms the amplitude-based nonlinear prediction error. For this type of noise, the nonlinear predictability score has a higher sensitivity for deterministic structure in noisy signals. It also yields a higher statistical power in a surrogate test of the null hypothesis of linear stochastic correlated signals. We show the high relevance of this improved performance in an application to electroencephalographic (EEG) recordings from epilepsy patients. Here the nonlinear predictability score again appears of higher sensitivity to nonrandomness. Importantly, it yields an improved contrast between signals recorded from brain areas where the first ictal EEG signal changes were detected (focal EEG signals) versus signals recorded from brain areas that were not involved at seizure onset (nonfocal EEG signals).

  12. Novel Organic Membrane-based Thin-film Microsensors for the Determination of Heavy Metal Cations

    Directory of Open Access Journals (Sweden)

    Michael J. Schöning

    2006-04-01

    Full Text Available A first step towards the fabrication and electrochemical evaluation of thin-filmmicrosensors based on organic PVC membranes for the determination of Hg(II, Cd(II,Pb(II and Cu(II ions in solutions has been realised. The membrane-coating mixture used inthe preparation of this new type of microsensors is incorporating PVC as supporting matrix,o-nitrophenyloctylether (o-NPOE as solvent mediator and a recently synthesizedHg[dimethylglyoxime(phene]2+ and Bis-(4-hydroxyacetophenone-ethylenediamine aselectroactive materials for Hg(II and Cd(II, respectively. A set of three commercialisedionophores for Cd(II, Pb(II and Cu(II has been also used for comparison. Thin-filmmicrosensors based on these membranes showed a Nernstian response of slope(26-30 mV/dec. for the respective tested cations. The potentiometric responsecharacteristics (linear range, pH range, detection limit and response time are comparablewith those obtained by conventional membranes as well as coated wire electrodes preparedfrom the same membrane. The realisation of the new organic membrane-based thin-filmmicrosensors overcomes the problem of an insufficient selectivity of solid-state-based thin-film sensors.

  13. Determining public policy and resource allocation priorities for mitigating natural hazards: a capabilities-based approach.

    Science.gov (United States)

    Murphy, Colleen; Gardoni, Paolo

    2007-12-01

    This paper proposes a Capabilities-based Approach to guide hazard mitigation efforts. First, a discussion is provided of the criteria that should be met by an adequate framework for formulating public policy and allocating resources. This paper shows why a common decision-aiding tool, Cost-benefit Analysis, fails to fulfill such criteria. A Capabilities-based Approach to hazard mitigation is then presented, drawing on the framework originally developed in the context of development economics and policy. The focus of a Capabilities-based Approach is protecting and promoting the well-being of individuals. Capabilities are dimensions of well-being and specified in terms of functionings. Functionings capture the various things of value an individual does or becomes in his or her life, including being alive, being healthy, and being sheltered. Capabilities refer to the real achievability of specific functionings. In the context of hazard mitigation, from a Capabilities-based Approach, decision- and policy-makers should consider the acceptability and tolerability of risks along with the affectability of hazards when determining policy formulation and resource allocation. Finally, the paper shows how the proposed approach satisfies the required criteria, and overcomes the limitations of Cost-benefit Analysis, while maintaining its strengths.

  14. Academic motivation in early adolescence based on self-determination theory

    Directory of Open Access Journals (Sweden)

    Šarčević Dušana

    2015-01-01

    Full Text Available This paper has tested the most frequently used instrument for assessing academic motivation in adolescents, which measures seven aspects of motivation in accordance with the self-determination theory. In the first version of this questionnaire, four factors were singled out in the Serbian sample. Based on the first version, the second one was made under the name AMS, containing 32 items with five-degree categories of answers ranging from total disagreement to total agreement. The AMS questionnaire was administered on the convenient sample of 1.106 respondents aged 10 to 15 of both genders (51% female. Four factors were extracted, defined as Internal motivation, External motivation, Introjected motivation and Amotivation. The self-determination continuum has not been confirmed completely since some dimensions have a different status of self-determination than it was expected, while psychometric characteristics of the scales proved to be very good. Compared to the first version, this version of the questionnaire has better psychometric characteristics, reflects more clearly the theoretical assumption about the aspects of academic motivation and partially confirms its continuum. Hence, it can be stated that the AMS questionnaire is a good enough indicator of academic motivation in early adolescence.

  15. Determining the Best Method for Estimating the Observed Level of Maximum Detrainment Based on Radar Reflectivity

    Energy Technology Data Exchange (ETDEWEB)

    Carletta, Nicholas D.; Mullendore, Gretchen L.; Starzec, Mariusz; Xi, Baike; Feng, Zhe; Dong, Xiquan

    2016-08-01

    Convective mass transport is the transport of mass from near the surface up to the upper troposphere and lower stratosphere (UTLS) by a deep convective updraft. This transport can alter the chemical makeup and water vapor balance of the UTLS, which affects cloud formation and the radiative properties of the atmosphere. It is therefore important to understand the exact altitudes at which mass is detrained from convection. The purpose of this study was to improve upon previously published methodologies for estimating the level of maximum detrainment (LMD) within convection using data from a single ground-based radar. Four methods were used to identify the LMD and validated against dual-Doppler derived vertical mass divergence fields for six cases with a variety of storm types. The best method for locating the LMD was determined to be the method that used a reflectivity texture technique to determine convective cores and a multi-layer echo identification to determine anvil locations. Although an improvement over previously published methods, the new methodology still produced unreliable results in certain regimes. The methodology worked best when applied to mature updrafts, as the anvil needs time to grow to a detectable size. Thus, radar reflectivity is found to be valuable in estimating the LMD, but storm maturity must also be considered for best results.

  16. Determination of reference values for optical properties of liquid phantoms based on Intralipid and India ink.

    Science.gov (United States)

    Spinelli, L; Botwicz, M; Zolek, N; Kacprzak, M; Milej, D; Sawosz, P; Liebert, A; Weigel, U; Durduran, T; Foschum, F; Kienle, A; Baribeau, F; Leclair, S; Bouchard, J-P; Noiseux, I; Gallant, P; Mermut, O; Farina, A; Pifferi, A; Torricelli, A; Cubeddu, R; Ho, H-C; Mazurenka, M; Wabnitz, H; Klauenberg, K; Bodnar, O; Elster, C; Bénazech-Lavoué, M; Bérubé-Lauzière, Y; Lesage, F; Khoptyar, D; Subash, A A; Andersson-Engels, S; Di Ninni, P; Martelli, F; Zaccanti, G

    2014-07-01

    A multi-center study has been set up to accurately characterize the optical properties of diffusive liquid phantoms based on Intralipid and India ink at near-infrared (NIR) wavelengths. Nine research laboratories from six countries adopting different measurement techniques, instrumental set-ups, and data analysis methods determined at their best the optical properties and relative uncertainties of diffusive dilutions prepared with common samples of the two compounds. By exploiting a suitable statistical model, comprehensive reference values at three NIR wavelengths for the intrinsic absorption coefficient of India ink and the intrinsic reduced scattering coefficient of Intralipid-20% were determined with an uncertainty of about 2% or better, depending on the wavelength considered, and 1%, respectively. Even if in this study we focused on particular batches of India ink and Intralipid, the reference values determined here represent a solid and useful starting point for preparing diffusive liquid phantoms with accurately defined optical properties. Furthermore, due to the ready availability, low cost, long-term stability and batch-to-batch reproducibility of these compounds, they provide a unique fundamental tool for the calibration and performance assessment of diffuse optical spectroscopy instrumentation intended to be used in laboratory or clinical environment. Finally, the collaborative work presented here demonstrates that the accuracy level attained in this work for optical properties of diffusive phantoms is reliable.

  17. Microsphere-based flow cytometric immunoassay for the determination of citrinin in red yeast rice.

    Science.gov (United States)

    Li, Yongning; Wu, Haiyan; Guo, Liangqia; Zheng, Yunquan; Guo, Yanghao

    2012-10-15

    The determination of citrinin (CIT) by a microsphere-based flow cytometric immunoassay (MFCI) has been developed. In the method, the carboxyl-modified microspheres were conjugated with CIT-Ovalbumin (OVA) antigen. CIT competed with the CIT-OVA antigen on the surface of the microspheres for the anti-CIT McAb. Under the optimised conditions, IC(50) value was 1.0 ng/mL and the limit of detection reached 0.005 ng/mL. The cross-reactivity was less than 0.01% against each of the four mycotoxins such as aflatoxin B(1) (AFB(1)), ochratoxin A (OTA), zearalenone (ZEA), deoxynilvalenol (DON). In the work, the MFCI could accurately determine CIT in the real red yeast rice. The systematic error was low with the coefficient of variation (CV) from 5.24% to 8.16% by the MFCI. The mean recovery of CIT from artificially contaminated red yeast rice was from 89% to 94%, with CV from 7.2% to 8.7%. The experimental data showed that the precision, sensitivity and specificity of the developed MFCI method for the determination of CIT were satisfactory. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Correlation and orbit determination of space objects based on sparse optical data

    Science.gov (United States)

    Milani, A.; Tommei, G.; Farnocchia, D.; Rossi, A.; Schildknecht, T.; Jehn, R.

    2011-11-01

    While building up a catalogue of Earth-orbiting objects, the available optical observations are typically sparse. In this case, no orbit determination is possible without previous correlation of observations obtained at different times. This correlation step is the most computationally intensive, and becomes more and more difficult as the number of objects to be discovered increases. In this paper, we tested two different algorithms, and the related prototype software, recently developed to solve the correlation problem for objects in geostationary orbit (GEO). The algorithms allow the accurate orbit determination by full least-squares solutions with all six orbital elements. The presence of a significant subpopulation of high area-to-mass ratio objects in the GEO region, strongly affected by non-gravitational perturbations, required to solve also for dynamical parameters describing these effects, that is to fit between six and eight free parameters for each orbit. The validation was based upon a set of real data, acquired from the European Space Agency (ESA) Space Debris Telescope (ESASDT) at the Teide Observatory (Canary Islands). We proved that it is possible to assemble a set of sparse observations into a set of objects with orbits. This would allow a survey strategy covering the region of interest in the sky just once per night. As a result, it would be possible to significantly reduce the requirements for a future telescope network, with respect to what would have been required with the previously known algorithms for correlation and orbit determination.

  19. A method based on Monte Carlo simulation for the determination of the G(E) function.

    Science.gov (United States)

    Chen, Wei; Feng, Tiancheng; Liu, Jun; Su, Chuanying; Tian, Yanjie

    2015-02-01

    The G(E) function method is a spectrometric method for the exposure dose estimation; this paper describes a method based on Monte Carlo method to determine the G(E) function of a 4″ × 4″ × 16″ NaI(Tl) detector. Simulated spectrums of various monoenergetic gamma rays in the region of 40 -3200 keV and the corresponding deposited energy in an air ball in the energy region of full-energy peak were obtained using Monte Carlo N-particle Transport Code. Absorbed dose rate in air was obtained according to the deposited energy and divided by counts of corresponding full-energy peak to get the G(E) function value at energy E in spectra. Curve-fitting software 1st0pt was used to determine coefficients of the G(E) function. Experimental results show that the calculated dose rates using the G(E) function determined by the authors' method are accordant well with those values obtained by ionisation chamber, with a maximum deviation of 6.31 %. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. A novel electrochemical sensor based on a molecularly imprinted polymer for the determination of epigallocatechin gallate.

    Science.gov (United States)

    Liu, Yanrui; Zhu, Lili; Hu, Yue; Peng, Xinsheng; Du, Jiangyan

    2017-04-15

    A novel electrochemical sensor based on the molecularly imprinted polymer (MIP) was fabricated by electrochemical polymerization of β-cyclodextrins (β-CD) and epigallocatechin-gallate (EGCG) on the graphene oxide (GO) modified glassy carbon (GO/GC) electrode for the first time. The MIP/GO/GC electrode exhibits an excellent ability of specific binding of EGCG and a rapid electrochemical response, high sensitivity and selectivity for determination of EGCG. This prepared MIP sensor presents distinct advantages over conventional electrochemical methods for EGCG determination because it is a one-step preparation and the template molecule can be easily removed by cyclic voltammetry scans, and no elution reagent is required. Under the optimal experimental conditions, the linear response range for EGCG concentrations by the sensor was 3×10(-8)mol/L to 1×10(-5)mol/L and the detection limit was 8.78×10(-9)mol/L(S/N=3). The results demonstrate that the proposed MIP sensor can be a potential alternative for the determination of EGCG in tea samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Crystalloid strong ion difference determines metabolic acid-base change during in vitro hemodilution.

    Science.gov (United States)

    Morgan, Thomas J; Venkatesh, Balasubramanian; Hall, Jonathan

    2002-01-01

    To determine the relationship between the strong ion difference (SID) of a diluting crystalloid and its metabolic acid-base effects on in vitro blood dilution. Prospective in vitro study. University research laboratory. Normal human blood. Three solutions were prepared, each with [Na] 140 mmol/L. [Cl-] for solutions 1, 2, and 3 was 120, 110, and 100 mmol/L, respectively, the other anion being HCO3-. SID values were thus 20, 30, and 40 mEq/L, respectively. Serial dilutions of well-oxygenated fresh venous blood were performed anaerobically by using each of solutions 1-3 as well as 0.9% saline (SID = 0 mEq/L) and Hartmann's solution (SID = -4 mEq/L). Blood gas and electrolyte analyses were performed before and after each dilution. Apart from dilutions with solution 3 (crystalloid SID 40 mEq/L) during which plasma SID did not change, plasma SID decreased during hemodilution. In contrast, base excess increased during hemodilution with solutions 3 and 2 (crystalloid SID 40 mEq/L and 30 mEq/L, respectively) and decreased only with the remaining three solutions. The relationships between hemoglobin concentrations and both plasma SID and whole blood base excess throughout dilution were linear, with slopes proportional to the SID of the diluent in each case. Linear regression revealed that the SID of crystalloid producing a zero base excess/hemoglobin concentration slope during blood dilution (i.e., no change in metabolic acid-base status) is 23.7 mEq/L. On in vitro hemodilution, there is a simple linear relationship between diluent crystalloid SID and the rate and direction of change of plasma SID and whole blood base excess. Direct extrapolation to in vivo situations such as acute normovolemic hemodilution and large volume correction of extracellular fluid deficits requires experimental confirmation.

  2. Electrochemical magnetic beads-based immunosensing platform for the determination of α-lactalbumin in milk.

    Science.gov (United States)

    Ruiz-Valdepeñas Montiel, Víctor; Campuzano, Susana; Torrente-Rodríguez, Rebeca M; Reviejo, A Julio; Pingarrón, José M

    2016-12-15

    Alpha-lactalbumin (α-LA) is one of the whey proteins in cows' milk that has been identified as allergenic. In this work, we present, for the first time, a very sensitive magnetic beads (MBs)-based immunosensor for the determination of α-LA. A sandwich configuration involving selective capture and horseradish peroxidase-labeled detector antibodies was implemented on carboxylic acid-modified magnetic beads, captured magnetically under the surface of a disposable screen-printed carbon electrode for amperometric detection using the hydroquinone (HQ)/H2O2 system. The α-LA immunosensor exhibited a wide linear range (37.0-5000pg/ml), a low limit of detection (LOD, 11.0pg/ml) and noteworthy selectivity against other non-target proteins. The MBs-based immunosensing platform was applied successfully for the determination of α-LA in several varieties of milk (raw and UHT cows' milk as well as human milk) and infant formulations. The results were corroborated with those obtained using a commercial ELISA method, thereby substantiating the analytical merits of this unique method. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Microfluidic paper-based chemiluminescence biosensor for simultaneous determination of glucose and uric acid.

    Science.gov (United States)

    Yu, Jinghua; Ge, Lei; Huang, Jiadong; Wang, Shoumei; Ge, Shenguang

    2011-04-07

    In this study, a novel microfluidic paper-based chemiluminescence analytical device (μPCAD) with a simultaneous, rapid, sensitive and quantitative response for glucose and uric acid was designed. This novel lab-on-paper biosensor is based on oxidase enzyme reactions (glucose oxidase and urate oxidase, respectively) and the chemiluminescence reaction between a rhodanine derivative and generated hydrogen peroxide in an acid medium. The possible chemiluminescence assay principle of this μPCAD is explained. We found that the simultaneous determination of glucose and uric acid could be achieved by differing the distances that the glucose and uric acid samples traveled. This lab-on-paper biosensor could provide reproducible results upon storage at 4 °C for at least 10 weeks. The application test of our μPCAD was then successfully performed with the simultaneous determination of glucose and uric acid in artificial urine. This study shows the successful integration of the μPCAD and the chemiluminescence method will be an easy-to-use, inexpensive, and portable alternative for point-of-care monitoring.

  4. A novel signal-off electrochemiluminescence biosensor for the determination of glucose based on double nanoparticles.

    Science.gov (United States)

    Liu, Linlin; Ma, Qiang; Li, Yang; Liu, ZiPing; Su, Xingguang

    2015-01-15

    In this work, a novel facile signal-off electrochemiluminescence (ECL) biosensor has been developed for the determination of glucose based on the integration of chitosan (CHIT), CdTe quantum dots (CdTe QDs) and Au nanoparticles (Au NPs) on the glassy carbon electrode (GCE). Chitosan displays high water permeability, hydrophilic property, strong hydrogel ability and good adhesion to load the double nanoparticles to the glassy carbon electrode surfaces. Au NPs are efficient glucose oxidase (GOx)-mimickess to catalytically oxidize glucose, similar to the natural process. Upon the addition of glucose, the Au NPs catalyzed glucose to produce gluconic acid and hydrogen peroxide (H2O2) based on the consumption of dissolved oxygen (O2), which resulted in a quenching effect on the ECL emission. Therefore, the determination of glucose could be achieved by monitoring the signal-off ECL biosensor. Under the optimum conditions, the ECL intensity of CdTe QDs and the concentration of glucose have a good linear relationship in the range of 0.01-10 mmol L(-1). The limit of detection for glucose was 5.28 μmol L(-1) (S/N=3). The biosensor showed good sensitivity, selectivity, reproducibility and stability. The proposed biosensor has been employed for the detection of glucose in human serum samples with satisfactory results. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. A heuristic ranking approach on capacity benefit margin determination using Pareto-based evolutionary programming technique.

    Science.gov (United States)

    Othman, Muhammad Murtadha; Abd Rahman, Nurulazmi; Musirin, Ismail; Fotuhi-Firuzabad, Mahmud; Rajabi-Ghahnavieh, Abbas

    2015-01-01

    This paper introduces a novel multiobjective approach for capacity benefit margin (CBM) assessment taking into account tie-line reliability of interconnected systems. CBM is the imperative information utilized as a reference by the load-serving entities (LSE) to estimate a certain margin of transfer capability so that a reliable access to generation through interconnected system could be attained. A new Pareto-based evolutionary programming (EP) technique is used to perform a simultaneous determination of CBM for all areas of the interconnected system. The selection of CBM at the Pareto optimal front is proposed to be performed by referring to a heuristic ranking index that takes into account system loss of load expectation (LOLE) in various conditions. Eventually, the power transfer based available transfer capability (ATC) is determined by considering the firm and nonfirm transfers of CBM. A comprehensive set of numerical studies are conducted on the modified IEEE-RTS79 and the performance of the proposed method is numerically investigated in detail. The main advantage of the proposed technique is in terms of flexibility offered to an independent system operator in selecting an appropriate solution of CBM simultaneously for all areas.

  6. Determining the degree of powder homogeneity using PC-based program

    Directory of Open Access Journals (Sweden)

    Đuragić Olivera M.

    2010-01-01

    Full Text Available The mixing of powders and the quality control of the obtained mixtures are critical operations involved in the processing of granular materials in chemical, metallurgical, food and pharmaceutical industries. Studies on mixing efficiency and the time needed for achieving homogeneity in the powder mashes production have significant importance. Depending on the characteristic of the materials, a number of methods have been used for the homogeneity tests. Very often, the degree of mixing has been determined by analyzing images of particle arrays in the sample using microscopy, photography and/or video tools. In this paper, a new PC-based method for determining the number of particles in the powder homogeneity tests has been developed. Microtracers®, red iron particles, were used as external tracer added before mixing. Iron particles in the samples of the mixtures were separated by rotary magnet and spread onto a filter paper. The filter paper was sprayed with 50% solution of ethanol for color development and the particles counted where the number of spots presented the concentration of added tracer. The number of spots was counted manually, as well as by the developed PC program. The program which analyzes scanned filter papers with spots is based on digital image analyses, where red spots were converted through few filters into a black and white, and counted. Results obtained by manual and PC counting were compared. A high correlation was established between the two counting methods.

  7. Hardware in the Loop Performance Assessment of LIDAR-Based Spacecraft Pose Determination.

    Science.gov (United States)

    Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele

    2017-09-24

    In this paper an original, easy to reproduce, semi-analytic calibration approach is developed for hardware-in-the-loop performance assessment of pose determination algorithms processing point cloud data, collected by imaging a non-cooperative target with LIDARs. The laboratory setup includes a scanning LIDAR, a monocular camera, a scaled-replica of a satellite-like target, and a set of calibration tools. The point clouds are processed by uncooperative model-based algorithms to estimate the target relative position and attitude with respect to the LIDAR. Target images, acquired by a monocular camera operated simultaneously with the LIDAR, are processed applying standard solutions to the Perspective-n-Points problem to get high-accuracy pose estimates which can be used as a benchmark to evaluate the accuracy attained by the LIDAR-based techniques. To this aim, a precise knowledge of the extrinsic relative calibration between the camera and the LIDAR is essential, and it is obtained by implementing an original calibration approach which does not need ad-hoc homologous targets (e.g., retro-reflectors) easily recognizable by the two sensors. The pose determination techniques investigated by this work are of interest to space applications involving close-proximity maneuvers between non-cooperative platforms, e.g., on-orbit servicing and active debris removal.

  8. Continuous glucose determination using fiber-based tunable mid-infrared laser spectroscopy

    Science.gov (United States)

    Yu, Songlin; Li, Dachao; Chong, Hao; Sun, Changyue; Xu, Kexin

    2014-04-01

    Wavelength-tunable laser spectroscopy in combination with a small-sized fiber-optic attenuated total reflection (ATR) sensor (fiber-based evanescent field analysis, FEFA) is reported for the continuous measurement of the glucose level. We propose a method of controlling and stabilizing the wavelength and power of laser emission and present a newly developed mid-infrared wavelength-tunable laser with a broad emission spectrum band of 9.19-9.77 μm (1024-1088 cm-1). The novel small-sized flow-through fiber-optic ATR sensor with long optical sensing length was used for glucose level determination. The experimental results indicate that the noise-equivalent concentration of this laser measurement system is as low as 3.8 mg/dL, which is among the most precise glucose measurements using mid-infrared spectroscopy. The sensitivity, which is three times that of conventional Fourier transform infrared spectrometer, was acquired because of the higher laser power and higher spectral resolution. The best prediction of the glucose concentration in phosphate buffered saline solution was achieved using the five-variable partial least-squares model, yielding a root-mean-square error of prediction as small as 3.5 mg/dL. The high sensitivity, multiple tunable wavelengths and small fiber-based sensor with long optical sensing length make glucose determination possible in blood or interstitial fluid in vivo.

  9. [Determination of soil exchangeable base cations by using atomic absorption spectrophotometer and extraction with ammonium acetate].

    Science.gov (United States)

    Zhang, Yu-ge; Xiao, Min; Dong, Yi-hua; Jiang, Yong

    2012-08-01

    A method to determine soil exchangeable calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na) by using atomic absorption spectrophotometer (AAS) and extraction with ammonium acetate was developed. Results showed that the accuracy of exchangeable base cation data with AAS method fits well with the national standard referential soil data. The relative errors for parallel samples of exchangeable Ca and Mg with 66 pair samples ranged from 0.02%-3.14% and 0.06%-4.06%, and averaged to be 1.22% and 1.25%, respectively. The relative errors for exchangeable K and Na with AAS and flame photometer (FP) ranged from 0.06%-8.39% and 0.06-1.54, and averaged to be 3.72% and 0.56%, respectively. A case study showed that the determination method for exchangeable base cations by using AAS was proven to be reliable and trustable, which could reflect the real situation of soil cation exchange properties in farmlands.

  10. Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex

    Directory of Open Access Journals (Sweden)

    Pilar Santolaria

    2016-01-01

    Full Text Available This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively. Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P < 0.001 although with important differences between bulls. A simultaneous evaluation of all the measured features by discriminant analysis revealed that nuclear area and average fluorescence intensity were the variables selected by stepwise discriminant function analysis as the best discriminators between SX and SY. In the second experiment, the sperm nuclear morphometric results from CASA-Morph in nonsexed (mixed SX and SY and sexed (SX semen samples from four bulls were compared. FISH allowed a successful classification of spermatozoa according to their sex chromosome content. X-sexed spermatozoa displayed a larger size and fluorescence intensity than nonsexed spermatozoa (P < 0.05. We conclude that the CASA-Morph fluorescence-based method has the potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.

  11. Determination of CME 3D parameters based on a new full ice-cream cone model

    Science.gov (United States)

    Na, Hyeonock; Moon, Yong-Jae

    2017-08-01

    In space weather forecast, it is important to determine three-dimensional properties of CMEs. Using 29 limb CMEs, we examine which cone type is close to a CME three-dimensional structure. We find that most CMEs have near full ice-cream cone structure which is a symmetrical circular cone combined with a hemisphere. We develop a full ice-cream cone model based on a new methodology that the full ice-cream cone consists of many flat cones with different heights and angular widths. By applying this model to 12 SOHO/LASCO halo CMEs, we find that 3D parameters from our method are similar to those from other stereoscopic methods (i.e., a triangulation method and a Graduated Cylindrical Shell model). In addition, we derive CME mean density (ρmean=Mtotal/Vcone) based on the full ice-cream cone structure. For several limb events, we determine CME mass by applying the Solarsoft procedure (e.g., cme_mass.pro) to SOHO/LASCO C3 images. CME volumes are estimated from the full ice-cream cone structure. From the power-law relationship between CME mean density and its height, we estimate CME mean densities at 20 solar radii (Rs). We will compare the CME densities at 20 Rs with their corresponding ICME densities.

  12. Surface plasmon resonance based spectrophotometric determination of medicinally important thiol compounds using unmodified silver nanoparticles

    Science.gov (United States)

    Vaishnav, Sandeep K.; Patel, Kuleshwar; Chandraker, Kumudini; Korram, Jyoti; Nagwanshi, Rekha; Ghosh, Kallol K.; Satnami, Manmohan L.

    2017-05-01

    The determination of thiol based biological molecules and drugs, such as cysteine (Cys) (I), α-lipoic acid (II), and sodium 2-sulfanylethane sulphonate (Mesna (III)) in human plasma are becoming progressively more important due to the growing body of knowledge about their essential role in numerous biological pathways. Herein we demonstrate a sensitive colorimetric sensor for the determination of medicinally important thiol drugs based on aggregation of the citrate capped silver nanoparticles (Ag NPs). This approach exploited the high affinity of thiols towards the Ag NPs surface which could tempt replacement of the citrate shell by the thiolate shell of target molecules, resulting in aggregation of the NPs through intermolecular electrostatic interaction or hydrogen-bonding. Because of aggregation, the plasmon band at around 400 nm decreases gradually, along with the appearance of a new band connoting a red shift. The calibration curves are derived from the intensity ratios of A530/A400, which display a linear relation in the range of 1 μM-150 μM, 5 μM-200 μM and 10 μM-130 μM, respectively. The obtained detection limits (3σ) were found to be 1.5 μM, 5.6 μM and 10.2 μM for compound I-III, respectively. The proposed method has been successfully applied for the detection of thiol compounds in real samples.

  13. New approach for the determination of aerosol refractive indices - Part I: Theoretical bases and numerical methodology

    Science.gov (United States)

    Herbin, H.; Pujol, O.; Hubert, P.; Petitprez, D.

    2017-10-01

    The knowledge of aerosol complex refractive indices on wide spectral range with high spectral resolution is important for many research fields and applications. Various combinations of experimental/theoretical/numerical approaches have been employed to determine the optical indices of aerosol particles. However, each approach has its own advantages and limitations that restrict its generalization. This article is first part of a work aimed at proposing a new technique for determining the optical constants of aerosols. Experimentally, the method is based on recording transmittance spectra of an aerosol flow from thermal infrared to UV-visible combined with the size distribution measurements. Herein, we present the theoretical and numerical bases of the algorithm developed to retrieve the imaginary and real parts of refractive indices. This model associates the Mie theory, the single subtractive Kramers-Kronig relations, and the optimal estimation method with an iterative process. In order to quantify the capabilities of the algorithm to retrieve complex refractive indices, inverse calculations are performed from simulated extinction spectra of Quartz particles whose some of optical properties are available in the literature. We have detailed each step of the procedure and performed some comparisons with the most currently employed methods. The impact of experimental accuracy and numerical simulation are investigated in terms of errors, and uncertainties on the retrieved real and imaginary parts of the complex optical index.

  14. Determinants of change in polypharmacy status in Switzerland: the population-based CoLaus study.

    Science.gov (United States)

    Abolhassani, Nazanin; Castioni, Julien; Marques-Vidal, Pedro; Vollenweider, Peter; Waeber, Gérard

    2017-09-01

    This study aimed to assess the prevalence, the change, and the determinants of change in polypharmacy in a population-based sample. Baseline (2003-2006) and follow-up (2009-2012) data are from 4679 participants aged between 35 and 75 years (53.5% women, mean age 52.6 ± 10.6 years) from the population of Lausanne, Switzerland. Polypharmacy was defined by the regular use of ≥5 drugs. Four categories of change were defined: never (no polypharmacy at baseline and follow-up), initiating (no polypharmacy at baseline but at follow-up), maintaining, or quitting. Polypharmacy increased from 7.7% at baseline to 15.3% at follow-up. Cardiovascular drugs were the most prescribed medicines at baseline and follow-up. Gender, age, obesity, smoking, previously diagnosed hypertension, or diabetes or dyslipidemia were significantly and independently associated with initiating and maintaining polypharmacy. In a population-based sample, prevalence of polypharmacy doubled over a 5.6-year period. The main determinants of initiating polypharmacy were age, overweight and obesity, smoking status, and previously diagnosed cardiovascular risk factors.

  15. Schiff Base modified on CPE electrode and PCB gold electrode for selective determination of silver ion

    Science.gov (United States)

    Leepheng, Piyawan; Suramitr, Songwut; Phromyothin, Darinee

    2017-09-01

    The schiff base was synthesized by 2,5-thiophenedicarboxaldehyde and 1,2,4-thiadiazole-3,5-diamine with condensation method. There was modified on carbon paste electrode (CPE) and Printed circuit board (PCB) gold electrode for determination silver ion. The schiff base modified electrodes was characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM), respectively. The electrochemical study was reported by cyclic voltammetry method and impedance spectroscopy using modified electrode as working electrode, platinum wire and Ag/AgCl as counter electrode and reference electrode, respectively. The modified electrodes have suitable detection for Ag+. The determination of silver ions using the modified electrodes depended linearly on Ag+ concentration in the range 1×10-10 M to 1×10-7 M, with cyclic voltammetry sensitivity were 2.51×108 μAM-1 and 1.88×108 μAM-1 for PCB gold electrode and CPE electrode, respectively, limits of detection were 5.33×10-9 M and 1.99×10-8 M for PCB gold electrode and CPE electrode, respectively. The modified electrodes have high accuracy, inexpensive and can applied to detection Ag+ in real samples.

  16. Determinants of employment-based private health insurance coverage in Denmark

    Directory of Open Access Journals (Sweden)

    Astrid Kiil

    2011-10-01

    Full Text Available This study estimates the determinants of having employment-based private health insurance (EPHI based on data from a survey of the Danish workforce conducted in 2009. The study contributes to the literature by exploring the role of satisfaction with the tax-financed health care system as a potential determinant of EPHI ownership and by taking into account that some employees receive EPHI free of charge, while others pay the premium out of their pre-tax income and thus make an actual choice. The results indicate that the probability of having EPHI is positively affected by private sector employment, size of the workplace, whether the workplace has a health scheme, income, being employed as a white-collar worker, and age until the age of 49, while the presence of subordinates, gender, education level, membership of 'denmark' and living in the capital region are not significantly associated with EPHI coverage. As expected, the characteristics related to the workplace are by far the quantitatively most important determinants. The association between EPHI and self-assessed health is found to be quadratic such that individuals in good self-assessed health are more likely to be covered by EPHI than those in excellent and fair, poor or very poor self-assessed health, respectively. Finally, the probability of having EPHI is found to be negatively related to the level of satisfaction with the tax-financed health care system. The findings of the study are not affected notably by distinguishing empirically between employees who receive EPHI free of charge and those who pay the premium out of their pre-tax income. Link to Appendix

  17. Fast GPU-based absolute intensity determination for energy-dispersive X-ray Laue diffraction

    Science.gov (United States)

    Alghabi, F.; Send, S.; Schipper, U.; Abboud, A.; Pietsch, U.; Kolb, A.

    2016-01-01

    This paper presents a novel method for fast determination of absolute intensities in the sites of Laue spots generated by a tetragonal hen egg-white lysozyme crystal after exposure to white synchrotron radiation during an energy-dispersive X-ray Laue diffraction experiment. The Laue spots are taken by means of an energy-dispersive X-ray 2D pnCCD detector. Current pnCCD detectors have a spatial resolution of 384 × 384 pixels of size 75 × 75 μm2 each and operate at a maximum of 400 Hz. Future devices are going to have higher spatial resolution and frame rates. The proposed method runs on a computer equipped with multiple Graphics Processing Units (GPUs) which provide fast and parallel processing capabilities. Accordingly, our GPU-based algorithm exploits these capabilities to further analyse the Laue spots of the sample. The main contribution of the paper is therefore an alternative algorithm for determining absolute intensities of Laue spots which are themselves computed from a sequence of pnCCD frames. Moreover, a new method for integrating spectral peak intensities and improved background correction, a different way of calculating mean count rate of the background signal and also a new method for n-dimensional Poisson fitting are presented.We present a comparison of the quality of results from the GPU-based algorithm with the quality of results from a prior (base) algorithm running on CPU. This comparison shows that our algorithm is able to produce results with at least the same quality as the base algorithm. Furthermore, the GPU-based algorithm is able to speed up one of the most time-consuming parts of the base algorithm, which is n-dimensional Poisson fitting, by a factor of more than 3. Also, the entire procedure of extracting Laue spots' positions, energies and absolute intensities from a raw dataset of pnCCD frames is accelerated by a factor of more than 3.

  18. Determinants of Benin elementary school science teachers' orientation toward inquiry-based instructional practices

    Science.gov (United States)

    Gado, Issaou

    The Republic of Benin (West Africa) undertook a nationwide curriculum reform that put an emphasis on inquiry-based instructional practices. Little, if any, research has been conducted to explore factors that could be related to teachers' orientation toward inquiry instructional practices. The purpose of this research study was to investigate factors and concerns that determine Benin elementary school teachers' orientation toward the use of inquiry-based instruction in the teaching of science. The study followed a naturalistic inquiry methodology combining a correlational ex post facto design and an observational case-study design. The theory of Planned Behavior was the conceptual framework used to design the study. Two hundred (N = 200) elementary school teachers and three (n = 3) case study participants were purposively selected. Data was gathered via the Revised Science Attitude Scale (Thompson & Shrigley, 1986), the Science Teachers' Ideological Preference Scale (Jones & Harty, 1978), open-ended questions, interviews, and classroom observations using audiorecorders, videorecorders, and the researcher-contextualized version of the Observational System for the Analysis of Classroom Instruction (Hough, 1966). Qualitative and quantitative data provided a deeper understanding of participants' responses. Quantitative measures indicated that Benin elementary school teachers have positive attitudes toward school science, significant positive orientation toward both inquiry-based instruction and traditional non inquiry-based instruction, and higher orientation toward inquiry-based instruction than traditional non inquiry-based instruction. Attitude toward handling materials for investigations was found to significantly contribute to the prediction of participants' inquiry orientation. Qualitative analyses of participants' responses indicated that the expectations of educational leaders, individual motivation to comply with the program, a perceived control of the

  19. Heterogeneous UO{sub 2} fuel irradiated up to a high burn-up: Investigation of the HBS and of fission product releases

    Energy Technology Data Exchange (ETDEWEB)

    Noirot, J., E-mail: jean.noirot@cea.fr [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Lamontagne, J. [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Nakae, N. [JNES, Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Kitagawa, T. [MNF, 622-1 Funaishikawa, Tokai-mura, Naka-gun, Ibaraki 319-1197 (Japan); Kosaka, Y. [NDC, 622-12 Funaishikawa, Tokai-mura, Ibaraki 319-1111 (Japan); Tverberg, T. [IFE, P.O. Box 173, NO-1751 Halden (Norway)

    2013-11-15

    A UO{sub 2} fuel with a heterogeneous distribution of {sup 235}U was irradiated up to a high burn-up in the Halden Boiling Water Reactor (HBWR). The last 100 days of irradiation were performed with an increased level of linear power. The effect of the heterogeneous fissile isotope distribution on the formation of the HBS was studied free of the possible influence of Pu which exists in heterogeneous MOX fuels. The HBS formed in {sup 235}U-rich agglomerates and its main characteristics were very similar to those of the HBS formed in Pu-rich agglomerates of heterogeneous MOX fuels. The maximum local contents of Nd and Xe before HBS formation were studied in this fuel. In addition to a Pu effect that promotes the HBS phenomenon, comparison with previous results for heterogeneous MOX fuels showed that the local fission product concentration was not the only parameter that has to be taken into consideration. It appears that the local actinide depletion by fission and/or the energy locally deposited through electronic interactions in the fission fragment recoils also have an effect on the HBS formation threshold. Moreover, a major release of fission gases from the peripheral {sup 235}U-rich agglomerates of HBS bubbles and a Cs radial movement are also evidenced in this heterogeneous UO{sub 2}. Cs deposits on the peripheral grain boundaries, including the HBS grain boundaries, are considered to reveal the release paths.

  20. A Study on the Radiation Source Effect to the Radiation Shielding Analysis for a Spent-Fuel Cask Design with Burnup-Credit

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soon Young; Kim, Kyung O [RADCORE Co., Ltd., Daejeon (Korea, Republic of); Ko, Jae Hoon; Lee, Gang Gu [Korea Nuclear Engineering and Service Corp., Daejeon (Korea, Republic of); Kim, Tae Man; Yoon, Jeong Hyun [Korea Raioactive waste Management Corp., Daejeon (Korea, Republic of)

    2011-06-15

    The radiation shielding analysis for a Burnup-credit (BUC) cask designed under the management of Korea Radioactive Waste Management Corporation (KRMC) was performed to examine the contribution of each radiation source affecting dose rate distribution around the cask. Various radiation sources, which contain neutron and gamma-ray sources placed in active fuel region and the activation source, and imaginary nuclear fuel were all considered in the MCNP calculation model to realistically simulate the actual situations. It was found that the maximum external and surface dose rates of the spent fuel cask were satisfied with the domestic standards both in normal and accident conditions. In normal condition, the radiation dose rate distribution around the cask was mainly influenced by activation source (60 Co radioisotope); in another case, the neutron emitted in active fuel region contributed about 90% to external dose rate at 1m distance from side surface of the cask. Besides, the contribution level of activation source was dramatically increased to the dose rates in top and bottom regions of the cask. From this study, it was recognized that the detailed investigation on the radiation sources should be performed conservatively and accurately in the process of radiation shielding analysis for a BUC cask.

  1. The application of hydrogen-palladium electrode for potentiometric acid-base determinations in tetrahydrofuran

    Directory of Open Access Journals (Sweden)

    Jokić Anja B.

    2013-01-01

    Full Text Available The application of the hydrogen-palladium electrode (H2/Pd as the indicator electrode for the determination of relative acidity scale (Es, mV of tetrahydrofuran (THF and the potentiometric titrations of acids in this solvent was investigated. The relative acidity scale tetrahydrofuran was determined from the difference half-neutralization potentials of perchloric acid and tetrabutylammonium hydroxide (TBAH, which were measured by using both H2/Pd-SCE and glass-SCE electrode pairs. The experimentally obtained value of Es scale THF with a H2/Pd-SCE electrode pair was 1155 mV, and those obtained with glass-SCE electrode pair 880 mV. By using a H2/Pd indicator electrode, the individual acids (benzoic acid, palmitic acid, maleic acid, acetyl acetone, α-naphthol and two component acid mixtures (benzoic acid + α-naphthol, palmitic acid + α-naphthol, maleic acid + α-naphthol and maleic acid + ftalic acid were titrated with a standard solution of TBAH. In addition, sodium methylate and potassium hydroxide proved to be very suitable titrating agents for titrating of the individual acids and the acids in mixtures, respectively. The relative error of the determination of acids in mixture was less than 3%. The results are in agreement with those obtained by a conventional glass electrode. The advantages of H2/Pd electrode over a glass electrode in potentiometric acid-base determinations in tetrahydrofuran lie in the following: this electrode gives wider relative acidity scale THF, higher the potential jumps at the titration end-point and relatively fast response time; furthermore, it is very durable, simple to prepare and can be used in the titrations of small volumes. [Projekat Ministarstva nauke Republike Srbije, br.172051

  2. Voltammetric determination of heparin based on its interaction with malachite green

    Directory of Open Access Journals (Sweden)

    Xueliang Niu

    2008-08-01

    Full Text Available In this paper malachite green (MG was used as a bioprobe to determine heparin concentration by linear sweep voltammetry on the dropping mercury working electrode (DME. In Britton-Robinson (B-R buffer solution of pH 1.5, MG had a well-defined second order derivative linear sweep voltammetric reductive peak at –0.618 V (vs. SCE. After the addition of heparin into the MG solution, the reductive peak current decreased apparently without the movement of peak potential. Based on the difference of the peak current, a new voltammetric method for the determination of heparin was established. The conditions for the binding reaction and the electrochemical detection were optimized. Under the selected experimental conditions the difference of peak current was directly proportional to the concentration of heparin in the range from 0.3 to 10.0 mg/L with the linear regression equation as ∆ip″ (nA = 360.19 C (mg/L + 178.88 (n = 15, γ = 0.998 and the detection limit as 0.28 mg/L (3σ. The effects of coexisting substances such as metal ions, amino acids on the determination of heparin were investigated and the results showed that this method had good selectivity. This method was further applied to determine the heparin content in heparin sodium injection samples with satisfactory results and good recovery. The stoichiometry of the biocomplex was calculated by the electrochemical method and the binding mechanism was further discussed.

  3. Fast mass spectrometry-based enantiomeric excess determination of proteinogenic amino acids.

    Science.gov (United States)

    Fleischer, Heidi; Thurow, Kerstin

    2013-03-01

    A rapid determination of the enantiomeric excess of proteinogenic amino acids is of great importance in various fields of chemical and biologic research and industries. Owing to their different biologic effects, enantiomers are interesting research subjects in drug development for the design of new and more efficient pharmaceuticals. Usually, the enantiomeric composition of amino acids is determined by conventional analytical methods such as liquid or gas chromatography or capillary electrophoresis. These analytical techniques do not fulfill the requirements of high-throughput screening due to their relative long analysis times. The method presented allows a fast analysis of chiral amino acids without previous time consuming chromatographic separation. The analytical measurements base on parallel kinetic resolution with pseudoenantiomeric mass tagged auxiliaries and were carried out by mass spectrometry with electrospray ionization. All 19 chiral proteinogenic amino acids were tested and Pro, Ser, Trp, His, and Glu were selected as model substrates for verification measurements. The enantiomeric excesses of amino acids with non-polar and aliphatic side chains as well as Trp and Phe (aromatic side chains) were determined with maximum deviations of the expected value less than or equal to 10ee%. Ser, Cys, His, Glu, and Asp were determined with deviations lower or equal to 14ee% and the enantiomeric excess of Tyr were calculated with 17ee% deviation. The total screening process is fully automated from the sample pretreatment to the data processing. The method presented enables fast measurement times about 1.38 min per sample and is applicable in the scope of high-throughput screenings.

  4. Quantum dot-based FRET for sensitive determination of hydrogen peroxide and glucose using tyramide reaction.

    Science.gov (United States)

    Huang, Xiangyi; Wang, Jinjie; Liu, Heng; Lan, Tao; Ren, Jicun

    2013-03-15

    In this paper, we report a new strategy for detection of hydrogen peroxide and glucose using quantum dot (QD)-based fluorescence resonance energy transfer (FRET) and tyramide reaction. The principle of FRET is based on highly sensitive reaction of a carbocyanine dye (Cy5) labeled tyramide and hydrogen peroxide catalyzed by horseradish peroxidase (HRP), and the fluorescence spectrum of QDs (EXmax 605 nm) partially overlaps with the absorption bands of Cy5. We firstly conjugated HRP to QDs, and then demonstrated an efficient FRET between HRP conjugated QDs (as energy donors) and tyramide labeled Cy5 (as energy acceptors) due to the formation of Cy5-labeled HRP-QDs assemblies in the presence of H₂O₂. We observed that the fluorescence Cy5 depended linearly on the H₂O₂ concentration within a range of concentration from 10 to 100 nM and the detection limit of this assay was 10 nM. Based on the principle for determination of H₂O₂, we develop a new strategy for assay of glucose by coupling with glucose oxidase-mediated reaction. The established methods were successfully used for determination of glucose levels in human sera, and the results obtained were in good agreement with commercially available method. Our method is at least 1 order of magnitude more sensitive than in the commercially available method. More importantly, our method described here can be extended to other assay designs using different oxidase enzymes, energy donors and energy acceptors, such as near-infrared (NIR)-to-visible upconversion nanoparticles and silicon and carbon QDs. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Paper membrane-based SERS platform for the determination of glucose in blood samples.

    Science.gov (United States)

    Torul, Hilal; Çiftçi, Hakan; Çetin, Demet; Suludere, Zekiye; Boyacı, Ismail Hakkı; Tamer, Uğur

    2015-11-01

    In this report, we present a paper membrane-based surface-enhanced Raman scattering (SERS) platform for the determination of blood glucose level using a nitrocellulose membrane as substrate paper, and the microfluidic channel was simply constructed by wax-printing method. The rod-shaped gold nanorod particles were modified with 4-mercaptophenylboronic acid (4-MBA) and 1-decanethiol (1-DT) molecules and used as embedded SERS probe for paper-based microfluidics. The SERS measurement area was simply constructed by dropping gold nanoparticles on nitrocellulose membrane, and the blood sample was dropped on the membrane hydrophilic channel. While the blood cells and proteins were held on nitrocellulose membrane, glucose molecules were moved through the channel toward the SERS measurement area. Scanning electron microscopy (SEM) was used to confirm the effective separation of blood matrix, and total analysis is completed in 5 min. In SERS measurements, the intensity of the band at 1070 cm(-1) which is attributed to B-OH vibration decreased depending on the rise in glucose concentration in the blood sample. The glucose concentration was found to be 5.43 ± 0.51 mM in the reference blood sample by using a calibration equation, and the certified value for glucose was 6.17 ± 0.11 mM. The recovery of the glucose in the reference blood sample was about 88 %. According to these results, the developed paper-based microfluidic SERS platform has been found to be suitable for use for the detection of glucose in blood samples without any pretreatment procedure. We believe that paper-based microfluidic systems may provide a wide field of usage for paper-based applications.

  6. A PCA-Based method for determining craniofacial relationship and sexual dimorphism of facial shapes.

    Science.gov (United States)

    Shui, Wuyang; Zhou, Mingquan; Maddock, Steve; He, Taiping; Wang, Xingce; Deng, Qingqiong

    2017-11-01

    Previous studies have used principal component analysis (PCA) to investigate the craniofacial relationship, as well as sex determination using facial factors. However, few studies have investigated the extent to which the choice of principal components (PCs) affects the analysis of craniofacial relationship and sexual dimorphism. In this paper, we propose a PCA-based method for visual and quantitative analysis, using 140 samples of 3D heads (70 male and 70 female), produced from computed tomography (CT) images. There are two parts to the method. First, skull and facial landmarks are manually marked to guide the model's registration so that dense corresponding vertices occupy the same relative position in every sample. Statistical shape spaces of the skull and face in dense corresponding vertices are constructed using PCA. Variations in these vertices, captured in every principal component (PC), are visualized to observe shape variability. The correlations of skull- and face-based PC scores are analysed, and linear regression is used to fit the craniofacial relationship. We compute the PC coefficients of a face based on this craniofacial relationship and the PC scores of a skull, and apply the coefficients to estimate a 3D face for the skull. To evaluate the accuracy of the computed craniofacial relationship, the mean and standard deviation of every vertex between the two models are computed, where these models are reconstructed using real PC scores and coefficients. Second, each PC in facial space is analysed for sex determination, for which support vector machines (SVMs) are used. We examined the correlation between PCs and sex, and explored the extent to which the choice of PCs affects the expression of sexual dimorphism. Our results suggest that skull- and face-based PCs can be used to describe the craniofacial relationship and that the accuracy of the method can be improved by using an increased number of face-based PCs. The results show that the accuracy of

  7. Elucidating determinants of aerosol composition through particle-type-based receptor modeling

    Directory of Open Access Journals (Sweden)

    M. L. McGuire

    2011-08-01

    Full Text Available An aerosol time-of-flight mass spectrometer (ATOFMS was deployed at a semi-rural site in southern Ontario to characterize the size and chemical composition of individual particles. Particle-type-based receptor modelling of these data was used to investigate the determinants of aerosol chemical composition in this region. Individual particles were classified into particle-types and positive matrix factorization (PMF was applied to their temporal trends to separate and cross-apportion particle-types to factors. The extent of chemical processing for each factor was assessed by evaluating the internal and external mixing state of the characteristic particle-types. The nine factors identified helped to elucidate the coupled interactions of these determinants. Nitrate-laden dust was found to be the dominant type of locally emitted particles measured by ATOFMS. Several factors associated with aerosol transported to the site from intermediate local-to-regional distances were identified: the Organic factor was associated with a combustion source to the north-west; the ECOC Day factor was characterized by nearby local-to-regional carbonaceous emissions transported from the south-west during the daytime; and the Fireworks factor consisted of pyrotechnic particles from the Detroit region following holiday fireworks displays. Regional aerosol from farther emissions sources was reflected through three factors: two Biomass Burning factors and a highly chemically processed Long Range Transport factor. The Biomass Burning factors were separated by PMF due to differences in chemical processing which were in part elucidated by the passage of two thunderstorm gust fronts with different air mass histories. The remaining two factors, ECOC Night and Nitrate Background, represented the night-time partitioning of nitrate to pre-existing particles of different origins. The distinct meteorological conditions observed during this month-long study in the summer of 2007

  8. Optimal sample size determinations from an industry perspective based on the expected value of information.

    Science.gov (United States)

    Willan, Andrew R

    2008-01-01

    Traditional sample size calculations for randomized clinical trials depend on somewhat arbitrarily chosen factors, such as type I and II errors. As an alternative, taking a societal perspective, and using the expected value of information based on Bayesian decision theory, a number of authors have recently shown how to determine the sample size that maximizes the expected net gain, i.e., the difference between the cost of the trial and the value of the information gained from the results. Other authors have proposed Bayesian methods to determine sample sizes from an industry perspective. The purpose of this article is to propose a Bayesian approach to sample size calculations from an industry perspective that attempts to determine the sample size that maximizes expected profit. A model is proposed for expected total profit that includes consideration of per-patient profit, disease incidence, time horizon, trial duration, market share, discount rate, and the relationship between the results and the probability of regulatory approval. The expected value of information provided by trial data is related to the increase in expected profit from increasing the probability of regulatory approval. The methods are applied to an example, including an examination of robustness. The model is extended to consider market share as a function of observed treatment effect. The use of methods based on the expected value of information can provide, from an industry perspective, robust sample size solutions that maximize the difference between the expected cost of the trial and the expected value of information gained from the results. The method is only as good as the model for expected total profit. Although the model probably has all the right elements, it assumes that market share, per-patient profit, and incidence are insensitive to trial results. The method relies on the central limit theorem which assumes that the sample sizes involved ensure that the relevant test statistics

  9. A practical method for extending the biuret assay to protein determination of corn-based products.

    Science.gov (United States)

    Liu, Zelong; Pan, Junhui

    2017-06-01

    A modified biuret method suitable for protein determination of corn-based products was developed by introducing a combination of an alkaline reagent with sodium dodecyl sulfate (reagent A) and heat treatments. The method was tested on seven corn-based samples. The results showed mostly good agreement (P>0.05) as compared to the Kjeldahl values. The proposed method was found to enhance the accuracy of prediction on zein content using bovine serum albumin as standard. Reagent A and sample treatment were proved to effectively improve protein solubilization for the thermally-dried corn-based products, e.g. corn gluten meal. The absorbance was stable for at least 1-h. Moreover, the whole measurement of protein content only needs 15-20min more than the traditional biuret assay, and can be performed in batches. The findings suggest that the proposed method could be a timesaving alternative for routine protein analyses in corn processing factories. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Multifamily determination of pesticide residues in soya-based nutraceutical products by GC/MS-MS.

    Science.gov (United States)

    Páleníková, Agneša; Martínez-Domínguez, Gerardo; Arrebola, Francisco Javier; Romero-González, Roberto; Hrouzková, Svetlana; Frenich, Antonia Garrido

    2015-04-15

    An analytical method based on a modified QuEChERS extraction coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was evaluated for the determination of 177 pesticides in soya-based nutraceutical products. The QuEChERS method was optimised and different extraction solvents and clean-up approaches were tested, obtaining the most efficient conditions with a mixture of sorbents (PSA, C18, GBC and Zr-Sep(+)). Recoveries were evaluated at 10, 50 and 100 μg/kg and ranged between 70% and 120%. Precision was expressed as relative standard deviation (RSD), and it was evaluated for more than 160 pesticides as intra and inter-day precision, with values always below 20% and 25%, respectively. Limits of detection (LODs) ranged from 0.1 to 10 μg/kg, whereas limits of quantification (LOQs) from 0.5 to 20 μg/kg. The applicability of the method was proved by analysing soya-based nutraceuticals. Two pesticides were found in these samples, malathion and pyriproxyfen, at 11.1 and 1.5 μg/kg respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Determinants of enrollment of informal sector workers in cooperative based health scheme in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Abdur Razzaque Sarker

    Full Text Available Providing access to affordable health care for the informal sector remains a considerable challenge for low income countries striving to make progress towards universal health coverage. The objective of the study is to identify the factors shaping the decision to enroll in a cooperative based health scheme for informal workers in Bangladesh and also help to identify the features of informal workers without health schemes and their likelihood of being insured.Data were derived from a cross-sectional in-house survey within the catchment area of a cooperative based health scheme in Bangladesh during April-June 2014, covering a total of 784 households (458 members and 326 non-members. Multivariate logistic regression model was used to identify factors associated with cooperative based health scheme and explanatory variables.This study found that a number of factors were significant determinants of health scheme participation including sex of household head, household composition, occupational category as well as involvement social financial safety net programs.Findings from this study can be suggestive for policy-makers interested in scaling up health insurance for informal workers in Bangladesh. Shared funding from this large informal sector can generate new resources for healthcare, which is in line with the healthcare financing strategy of Bangladesh as well as the recommendation of the World Health Organization for developing social health insurance as part of the path to Universal Health Coverage.

  12. Building a substitute model of a bolster based on experimentally determined deflection

    Science.gov (United States)

    Zgoll, F.; Götze, T.; Volk, W.

    2017-09-01

    The high design requirements in the production of car body parts necessitate an exact closure of the forming tools in deep drawing processes. The tool closure is directly related to the machine elastic behaviour. To significantly reduce efforts and save time during ramp up of new forming tools, knowledge of the expected machine behaviour should be considered during the virtual development process of the tools. A prerequisite for that is building a validated machine-specific substitute model of the forming press composed of bolster, ram and drawing cushion. In this contribution, a substitute model with the help of finite element analysis (FEA) based on experimentally determined deflection is presented. The deflection measurements are performed by means of a multifunctional press measuring system from Volkswagen.

  13. Determination of gas composition in a biogas plant using a Raman-based sensor system

    Science.gov (United States)

    Eichmann, S. C.; Kiefer, J.; Benz, J.; Kempf, T.; Leipertz, A.; Seeger, T.

    2014-07-01

    We propose a gas sensor, based on spontaneous Raman scattering, for the compositional analysis of typical biogas mixtures and present a description of the sensor, as well as of the calibration procedure, which allows the quantification of condensable gases. Moreover, we carry out a comprehensive characterization of the system, in order to determine the measurement uncertainty, as well as influences of temperature and pressure fluctuation. Finally, the sensor is applied at different locations inside a plant in which biogas is produced from renewable raw materials. The composition is monitored after fermenting, after purification and after the final conditioning, where natural gas is added. The Raman sensor is able to detect all the relevant gas components, i.e. CH4, CO2, N2 and H2O, and report their individual concentrations over time. The results were compared to reference data from a conventional gas analyzer and good agreement was obtained.

  14. Accurate Determination of Geographical Origin of Tea Based on Terahertz Spectroscopy

    Directory of Open Access Journals (Sweden)

    Mingliang Li

    2017-02-01

    Full Text Available This paper proposes a structured model for the identification of green tea, as well as tracing its geographical origins. Considering that the features of different types of green tea are similar under THz time-domain spectroscopy, we designed a program to perform principal component analysis (PCA of the spectroscopic data of various green tea samples and to determine the data sequences of principal components. We then established a training set for the principal components to train a support vector machine (SVM model via a genetic algorithm (GA. We used this model to optimize the parameters and develop a GA-based SVM model with an identification rate of 96.25% for the tested samples. Taken together, our results confirm that THz time-domain spectroscopy combined with GA-SVM can be effectively applied to rapidly identify types of green tea with different geographical origins.

  15. Novel thermal efficiency-based model for determination of thermal conductivity of membrane distillation membranes

    Energy Technology Data Exchange (ETDEWEB)

    Vanneste, Johan; Bush, John A.; Hickenbottom, Kerri L.; Marks, Christopher A.; Jassby, David; Turchi, Craig S.; Cath, Tzahi Y.

    2018-02-01

    Development and selection of membranes for membrane distillation (MD) could be accelerated if all performance-determining characteristics of the membrane could be obtained during MD operation without the need to recur to specialized or cumbersome porosity or thermal conductivity measurement techniques. By redefining the thermal efficiency, the Schofield method could be adapted to describe the flux without prior knowledge of membrane porosity, thickness, or thermal conductivity. A total of 17 commercially available membranes were analyzed in terms of flux and thermal efficiency to assess their suitability for application in MD. The thermal-efficiency based model described the flux with an average %RMSE of 4.5%, which was in the same range as the standard deviation on the measured flux. The redefinition of the thermal efficiency also enabled MD to be used as a novel thermal conductivity measurement device for thin porous hydrophobic films that cannot be measured with the conventional laser flash diffusivity technique.

  16. Microarray-based whole-genome hybridization as a tool for determining procaryotic species relatedness

    Energy Technology Data Exchange (ETDEWEB)

    Wu, L.; Liu, X.; Fields, M.W.; Thompson, D.K.; Bagwell, C.E.; Tiedje, J. M.; Hazen, T.C.; Zhou, J.

    2008-01-15

    The definition and delineation of microbial species are of great importance and challenge due to the extent of evolution and diversity. Whole-genome DNA-DNA hybridization is the cornerstone for defining procaryotic species relatedness, but obtaining pairwise DNA-DNA reassociation values for a comprehensive phylogenetic analysis of procaryotes is tedious and time consuming. A previously described microarray format containing whole-genomic DNA (the community genome array or CGA) was rigorously evaluated as a high-throughput alternative to the traditional DNA-DNA reassociation approach for delineating procaryotic species relationships. DNA similarities for multiple bacterial strains obtained with the CGA-based hybridization were comparable to those obtained with various traditional whole-genome hybridization methods (r=0.87, P<0.01). Significant linear relationships were also observed between the CGA-based genome similarities and those derived from small subunit (SSU) rRNA gene sequences (r=0.79, P<0.0001), gyrB sequences (r=0.95, P<0.0001) or REP- and BOX-PCR fingerprinting profiles (r=0.82, P<0.0001). The CGA hybridization-revealed species relationships in several representative genera, including Pseudomonas, Azoarcus and Shewanella, were largely congruent with previous classifications based on various conventional whole-genome DNA-DNA reassociation, SSU rRNA and/or gyrB analyses. These results suggest that CGA-based DNA-DNA hybridization could serve as a powerful, high-throughput format for determining species relatedness among microorganisms.

  17. A Novel Acoustic Liquid Level Determination Method for Coal Seam Gas Wells Based on Autocorrelation Analysis

    Directory of Open Access Journals (Sweden)

    Ximing Zhang

    2017-11-01

    Full Text Available In coal seam gas (CSG wells, water is periodically removed from the wellbore in order to keep the bottom-hole flowing pressure at low levels, facilitating the desorption of methane gas from the coal bed. In order to calculate gas flow rate and further optimize well performance, it is necessary to accurately monitor the liquid level in real-time. This paper presents a novel method based on autocorrelation function (ACF analysis for determining the liquid level in CSG wells under intense noise conditions. The method involves the calculation of the acoustic travel time in the annulus and processing the autocorrelation signal in order to extract the weak echo under high background noise. In contrast to previous works, the non-linear dependence of the acoustic velocity on temperature and pressure is taken into account. To locate the liquid level of a coal seam gas well the travel time is computed iteratively with the non-linear velocity model. Afterwards, the proposed method is validated using experimental laboratory investigations that have been developed for liquid level detection under two scenarios, representing the combination of low pressure, weak signal, and intense noise generated by gas flowing and leakage. By adopting an evaluation indicator called Crest Factor, the results have shown the superiority of the ACF-based method compared to Fourier filtering (FFT. In the two scenarios, the maximal measurement error from the proposed method was 0.34% and 0.50%, respectively. The latent periodic characteristic of the reflected signal can be extracted by the ACF-based method even when the noise is larger than 1.42 Pa, which is impossible for FFT-based de-noising. A case study focused on a specific CSG well is presented to illustrate the feasibility of the proposed approach, and also to demonstrate that signal processing with autocorrelation analysis can improve the sensitivity of the detection system.

  18. Determining suitability of Large Aperture Scintillometer for validating remote sensing based evapotranspiration maps

    Science.gov (United States)

    Paul, G.; Gowda, P. H.; Howell, T. A.; Basu, S.; Colaizzi, P. D.; Marek, T.

    2013-12-01

    Scintillation method is a relatively new technique for measuring the sensible heat and water fluxes over land surfaces. Path integrating capabilities of scintillometer over heterogeneous landscapes make it a potential tool for comparing the energy fluxes derived from remote sensing based energy balance algorithms. For this reason, scintillometer-derived evapotranspiration (ET) fluxes are being used to evaluate remote sensing based energy balance algorithms for their ability to estimate ET fluxes. However, LAS' (Large Aperture Scintillometer) ability to derive ET fluxes is not thoroughly tested. The objective of this study was to evaluate LAS- and Surface Energy Balance System (SEBS)-derived fluxes against lysimetric data to determine LAS' suitability for validating remote sensing based evapotranspiration (ET) maps. The study was conducted during the Bushland Evapotranspiration and Agricultural Remote sensing EXperiment - 2008 (BEAREX-08) at the USDA-ARS Conservation and Production Research Laboratory (CPRL), Bushland, Texas. SEBS was coded in a GIS environment to retrieve ET fluxes from the high resolution imageries acquired using airborne multispectral sensors. The CPRL has four large weighing lysimeters (3 m long x 3 m wide x 2.4 m deep), each located in the middle of approximately 5 ha fields, arranged in a block pattern. The two lysimeter fields located on the east (NE and SE) were managed under irrigated conditions, and the other two lysimeters on the west (NW and SW) were under dryland management. Each lysimeter field was equipped with an automated weather station that provided measurements for net radiation (Rn), Ts, soil heat flux (Go), Ta, relative humidity, and wind speed. During BEAREX08, the NE and SE fields were planted to cotton on May 21, and the NW and SW dryland lysimeters fields were planted to cotton on June 5. One LAS each was deployed across two large dryland lysimeter fields (NW and SW) and two large irrigated lysimeter fields (NE and SE). The

  19. Directly patching high-level exchange-correlation potential based on fully determined optimized effective potentials.

    Science.gov (United States)

    Huang, Chen; Chi, Yu-Chieh

    2017-12-28

    The key element in Kohn-Sham (KS) density functional theory is the exchange-correlation (XC) potential. We recently proposed the exchange-correlation potential patching (XCPP) method with the aim of directly constructing high-level XC potential in a large system by patching the locally computed, high-level XC potentials throughout the system. In this work, we investigate the patching of the exact exchange (EXX) and the random phase approximation (RPA) correlation potentials. A major challenge of XCPP is that a cluster's XC potential, obtained by solving the optimized effective potential equation, is only determined up to an unknown constant. Without fully determining the clusters' XC potentials, the patched system's XC potential is "uneven" in the real space and may cause non-physical results. Here, we developed a simple method to determine this unknown constant. The performance of XCPP-RPA is investigated on three one-dimensional systems: H20, H10Li8, and the stretching of the H19-H bond. We investigated two definitions of EXX: (i) the definition based on the adiabatic connection and fluctuation dissipation theorem (ACFDT) and (ii) the Hartree-Fock (HF) definition. With ACFDT-type EXX, effective error cancellations were observed between the patched EXX and the patched RPA correlation potentials. Such error cancellations were absent for the HF-type EXX, which was attributed to the fact that for systems with fractional occupation numbers, the integral of the HF-type EXX hole is not -1. The KS spectra and band gaps from XCPP agree reasonably well with the benchmarks as we make the clusters large.

  20. Directly patching high-level exchange-correlation potential based on fully determined optimized effective potentials

    Science.gov (United States)

    Huang, Chen; Chi, Yu-Chieh

    2017-12-01

    The key element in Kohn-Sham (KS) density functional theory is the exchange-correlation (XC) potential. We recently proposed the exchange-correlation potential patching (XCPP) method with the aim of directly constructing high-level XC potential in a large system by patching the locally computed, high-level XC potentials throughout the system. In this work, we investigate the patching of the exact exchange (EXX) and the random phase approximation (RPA) correlation potentials. A major challenge of XCPP is that a cluster's XC potential, obtained by solving the optimized effective potential equation, is only determined up to an unknown constant. Without fully determining the clusters' XC potentials, the patched system's XC potential is "uneven" in the real space and may cause non-physical results. Here, we developed a simple method to determine this unknown constant. The performance of XCPP-RPA is investigated on three one-dimensional systems: H20, H10Li8, and the stretching of the H19-H bond. We investigated two definitions of EXX: (i) the definition based on the adiabatic connection and fluctuation dissipation theorem (ACFDT) and (ii) the Hartree-Fock (HF) definition. With ACFDT-type EXX, effective error cancellations were observed between the patched EXX and the patched RPA correlation potentials. Such error cancellations were absent for the HF-type EXX, which was attributed to the fact that for systems with fractional occupation numbers, the integral of the HF-type EXX hole is not -1. The KS spectra and band gaps from XCPP agree reasonably well with the benchmarks as we make the clusters large.

  1. A Surface Plasmon Resonance-Based Method for Detection and Determination of Cannabinoids Using Silver Nanoparticles

    Science.gov (United States)

    Amjadi, M.; Sodouri, T.

    2014-05-01

    In this work, a simple colorimetric method based on the formation of silver nanoparticles (Ag NPs) was developed for the determination of cannabinoids including Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD) and cannabinol (CBN). These compounds in a basic solution at 80°C reduce [Ag(NH3)2]+ to form Ag NPs. The produced NPs were characterized by transmission electron microscopy and UV-Vis absorption spectroscopy. The brown-yellow color of the solution that results from the localized surface plasmon resonance of Ag NPs can be observed by the bare eye. The calibration graph obtained by plotting the absorbance at 410 nm versus the concentration of each analyte was linear in the range of 0.1-5.0 μg/ml for all tested cannabinoids. The limits of detection were 0.065, 0.077, and 0.052 μg/ml for Δ9-THC, CBN and CBD, respectively. The developed method was applied to the determination of total cannabinoids in hashish.

  2. Enhanced spectrophotometric determination of Losartan potassium based on its physicochemical interaction with cationic surfactant

    Science.gov (United States)

    Abdel-Fattah, Laila; Abdel-Aziz, Lobna; Gaied, Mariam

    2015-02-01

    In this study, a simple and sensitive spectrophotometric method was developed for determination of Losartan potassium (LST K), an angiotensin-II receptor (type AT1) antagonist, in presence of cationic surfactant cetyltrimethylammonium bromide (CTAB). The physicochemical interaction of LST K with CTAB was investigated. The effect of cationic micelles on the spectroscopic and acid-base properties of LST K was studied at pH 7.4. The binding constant (Kb) and the partition coefficient (Kx) of LST K-CTAB were 1.62 × 105 M-1 and 1.38 × 105; respectively. The binding of LST K to CTAB micelles implied a shift in drug acidity constant (ΔpKa = 0.422). The developed method is linear over the range 0.5-28 μg mL-1. The accuracy was evaluated and was found to be 99.79 ± 0.509% and the relative standard deviation for intraday and interday precision was 0.821 and 0.963; respectively. The method was successfully applied to determine LST K in pharmaceutical formulations.

  3. Determination of fractional flow reserve (FFR) based on scaling laws: a simulation study

    Science.gov (United States)

    Wong, Jerry T.; Molloi, Sabee

    2008-07-01

    Fractional flow reserve (FFR) provides an objective physiological evaluation of stenosis severity. A technique that can measure FFR using only angiographic images would be a valuable tool in the cardiac catheterization laboratory. To perform this, the diseased blood flow can be measured with a first pass distribution analysis and the theoretical normal blood flow can be estimated from the total coronary arterial volume based on scaling laws. A computer simulation of the coronary arterial network was used to gain a better understanding of how hemodynamic conditions and coronary artery disease can affect blood flow, arterial volume and FFR estimation. Changes in coronary arterial flow and volume due to coronary stenosis, aortic pressure and venous pressure were examined to evaluate the potential use of flow and volume for FFR determination. This study showed that FFR can be estimated using arterial volume and a scaling coefficient corrected for aortic pressure. However, variations in venous pressure were found to introduce some error in FFR estimation. A relative form of FFR was introduced and was found to cancel out the influence of pressure on coronary flow, arterial volume and FFR estimation. The use of coronary flow and arterial volume for FFR determination appears promising.

  4. Rotation Matrix Method Based on Ambiguity Function for GNSS Attitude Determination.

    Science.gov (United States)

    Yang, Yingdong; Mao, Xuchu; Tian, Weifeng

    2016-06-08

    Global navigation satellite systems (GNSS) are well suited for attitude determination. In this study, we use the rotation matrix method to resolve the attitude angle. This method achieves better performance in reducing computational complexity and selecting satellites. The condition of the baseline length is combined with the ambiguity function method (AFM) to search for integer ambiguity, and it is validated in reducing the span of candidates. The noise error is always the key factor to the success rate. It is closely related to the satellite geometry model. In contrast to the AFM, the LAMBDA (Least-squares AMBiguity Decorrelation Adjustment) method gets better results in solving the relationship of the geometric model and the noise error. Although the AFM is more flexible, it is lack of analysis on this aspect. In this study, the influence of the satellite geometry model on the success rate is analyzed in detail. The computation error and the noise error are effectively treated. Not only is the flexibility of the AFM inherited, but the success rate is also increased. An experiment is conducted in a selected campus, and the performance is proved to be effective. Our results are based on simulated and real-time GNSS data and are applied on single-frequency processing, which is known as one of the challenging case of GNSS attitude determination.

  5. Ground-based astrometry calibrated by Gaia DR1: new perspectives in asteroid orbit determination

    Science.gov (United States)

    Spoto, F.; Tanga, P.; Bouquillon, S.; Desmars, J.; Hestroffer, D.; Mignard, F.; Altmann, M.; Herald, D.; Marchant, J.; Barache, C.; Carlucci, T.; Lister, T.; Taris, F.

    2017-10-01

    Context. The Gaia Data Release 1 (GDR1) is a first, important step on the path of evolution of astrometric accuracy towards a much improved situation. Although asteroids are not present in GDR1, this intermediate release already impacts asteroid astrometry. Aims: Our goal is to investigate how the GDR1 can change the approach to a few typical problems, including the determination of orbits from short-arc astrometry, the exploitation of stellar occultations, and the impact risk assessment. Methods: We employ optimised asteroid orbit determination tools, and study the resulting orbit accuracy and post-fit residuals. For this goal, we use selected ground-based asteroid astrometry, and occultation events observed in the past. All measurements are calibrated by using GDR1 stars. Results: We show that, by adopting GDR1, very short measurement arcs can already provide interesting orbital solutions, capable of correctly identifying near-Earth asteroids (NEAs) and providing a much more accurate risk rating. We also demonstrate that occultations, previously used to derive asteroid size and shapes, now reach a new level of accuracy at which they can be fruitfully used to obtain astrometry at the level of accuracy of Gaia star positions.

  6. Development of PCR‐Based Markers to Determine the Sex of Kelps

    Science.gov (United States)

    Lipinska, Agnieszka P.; Ahmed, Sophia; Peters, Akira F.; Faugeron, Sylvain; Cock, J. Mark; Coelho, Susana M.

    2015-01-01

    Sex discriminating genetic markers are commonly used to facilitate breeding programs in economically and ecologically important animal and plant species. However, despite their considerable economic and ecological value, the development of sex markers for kelp species has been very limited. In this study, we used the recently described sequence of the sex determining region (SDR) of the brown algal model Ectocarpus to develop novel DNA-based sex-markers for three commercially relevant kelps: Laminaria digitata, Undaria pinnatifida and Macrocystis pyrifera. Markers were designed within nine protein coding genes of Ectocarpus male and female (U/V) sex chromosomes and tested on gametophytes of the three kelp species. Seven primer pairs corresponding to three loci in the Ectocarpus SDR amplified sex-specific bands in the three kelp species, yielding at least one male and one female marker for each species. Our work has generated the first male sex-specific markers for L. digitata and U. pinnatifida, as well as the first sex markers developed for the genus Macrocystis. The markers and methodology presented here will not only facilitate seaweed breeding programs but also represent useful tools for population and demography studies and provide a means to investigate the evolution of sex determination across this largely understudied eukaryotic group. PMID:26496392

  7. Electrochemical sensor based on magnetic molecularly imprinted nanoparticles modified magnetic electrode for determination of Hb.

    Science.gov (United States)

    Sun, Binghua; Ni, Xinjiong; Cao, Yuhua; Cao, Guangqun

    2017-05-15

    A fast and selective electrochemical sensor for determination of hemoglobin (Hb) was developed based on magnetic molecularly imprinted nanoparticles modified on the magnetic glassy carbon electrode. The nanoparticles Fe3O4@SiO2 with a magnetic core and a molecularly imprinted shell had regular structures and good monodispersity. Hb could be determined directly by electrochemical oxidization with the modified electrode. A magnetic field increased electrochemical response to Hb by two times. Imprinting Hb on the surface of Fe3O4@SiO2 shortened the response time within 7min. Under optimum conditions, the imprinting factor toward the non-imprinted sensor was 2.8, and the separation factor of Hb to horseradish peroxidase was 2.6. The oxidation peak current had a linear relationship with Hb concentration ranged from 0.005mg/ml to 0.1mg/ml with a detection limit (S/N =3) of 0.0010mg/ml. The sensors were successfully applied to analysis of Hb in whole blood samples with recoveries between 95.7% and 105%. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The Brady Bunch? New evidence for nominative determinism in patients' health: retrospective, population based cohort study.

    Science.gov (United States)

    Keaney, John J; Groarke, John D; Galvin, Zita; McGorrian, Catherine; McCann, Hugh A; Sugrue, Declan; Keelan, Edward; Galvin, Joseph; Blake, Gavin; Mahon, Niall G; O'Neill, James

    2013-12-12

    To ascertain whether a name can influence a person's health, by assessing whether people with the surname "Brady" have an increased prevalence of bradycardia. Retrospective, population based cohort study. One university teaching hospital in Dublin, Ireland. People with the surname "Brady" in Dublin, determined through use of an online telephone directory. Prevalence of participants who had pacemakers inserted for bradycardia between 1 January 2007 and 28 February 2013. 579 (0.36%) of 161,967 people who were listed on the Dublin telephone listings had the surname "Brady." The proportion of pacemaker recipients was significantly higher among Bradys (n=8, 1.38%) than among non-Bradys (n=991, 0.61%; P=0.03). The unadjusted odds ratio (95% confidence interval) for pacemaker implantation among individuals with the surname Brady compared with individuals with other surnames was 2.27 (1.13 to 4.57). Patients named Brady are at increased risk of needing pacemaker implantation compared with the general population. This finding shows a potential role for nominative determinism in health.

  9. The Brady Bunch? New evidence for nominative determinism in patients’ health: retrospective, population based cohort study

    Science.gov (United States)

    Groarke, John D; Galvin, Zita; McGorrian, Catherine; McCann, Hugh A; Sugrue, Declan; Keelan, Edward; Galvin, Joseph; Blake, Gavin; Mahon, Niall G; O’Neill, James

    2013-01-01

    Objective To ascertain whether a name can influence a person’s health, by assessing whether people with the surname “Brady” have an increased prevalence of bradycardia. Design Retrospective, population based cohort study. Setting One university teaching hospital in Dublin, Ireland. Participants People with the surname “Brady” in Dublin, determined through use of an online telephone directory. Main outcome measure Prevalence of participants who had pacemakers inserted for bradycardia between 1 January 2007 and 28 February 2013. Results 579 (0.36%) of 161 967 people who were listed on the Dublin telephone listings had the surname “Brady.” The proportion of pacemaker recipients was significantly higher among Bradys (n=8, 1.38%) than among non-Bradys (n=991, 0.61%; P=0.03). The unadjusted odds ratio (95% confidence interval) for pacemaker implantation among individuals with the surname Brady compared with individuals with other surnames was 2.27 (1.13 to 4.57). Conclusions Patients named Brady are at increased risk of needing pacemaker implantation compared with the general population. This finding shows a potential role for nominative determinism in health. PMID:24336304

  10. Development of PCR-Based Markers to Determine the Sex of Kelps.

    Directory of Open Access Journals (Sweden)

    Agnieszka P Lipinska

    Full Text Available Sex discriminating genetic markers are commonly used to facilitate breeding programs in economically and ecologically important animal and plant species. However, despite their considerable economic and ecological value, the development of sex markers for kelp species has been very limited. In this study, we used the recently described sequence of the sex determining region (SDR of the brown algal model Ectocarpus to develop novel DNA-based sex-markers for three commercially relevant kelps: Laminaria digitata, Undaria pinnatifida and Macrocystis pyrifera. Markers were designed within nine protein coding genes of Ectocarpus male and female (U/V sex chromosomes and tested on gametophytes of the three kelp species. Seven primer pairs corresponding to three loci in the Ectocarpus SDR amplified sex-specific bands in the three kelp species, yielding at least one male and one female marker for each species. Our work has generated the first male sex-specific markers for L. digitata and U. pinnatifida, as well as the first sex markers developed for the genus Macrocystis. The markers and methodology presented here will not only facilitate seaweed breeding programs but also represent useful tools for population and demography studies and provide a means to investigate the evolution of sex determination across this largely understudied eukaryotic group.

  11. Spectrophotometric Determination of Rifampicin in Bulk Drug and Pharmaceutical Formulations Based on Redox and Complexation Reactions

    Science.gov (United States)

    Swamy, N.; Basavaiah, K.

    2017-09-01

    Two spectrophotometric methods were developed and validated for the determination of rifampicin (RIF) in bulk form, formulations, and spiked human urine. The first method is based on the reduction of the Folin-Ciocalteu (FC) reagent by RIF to form a blue colored chromogen with λmax at 760 nm (the FCR method). In the second method, iron(III) is reduced by RIF in a neutral medium, and the resulting iron(II) is complexed with ferricyanide to form a Prussian blue peaking at 750 nm (the FFC method). Under optimum conditions, Beer's law enabled the determination of the drug in the concentration ranges 1-35 and 2.5-50 μg/mL with apparent molar absorptivities of 2.72 × 104 and 1.63×104 L/(mol × cm) for the FCR and FFC methods, respectively. The Sandell sensitivity, limits of detection (LOD), and quantification (LOQ) values were also reported for both methods. The precision of the methods, with % RSD of additives and spiked human urine without interference from endogenous substances. A statistical analysis indicated that there was no significant difference between the results obtained by the developed methods and the official method.

  12. Determining next best view based on occlusion information in a single depth image of visual object

    Directory of Open Access Journals (Sweden)

    Shihui Zhang

    2016-12-01

    Full Text Available How to determine the camera’s next best view is a challenging problem in vision field. A next best view approach is proposed based on occlusion information in a single depth image. First, the occlusion detection is accomplished for the depth image of visual object in current view to obtain the occlusion boundary and the nether adjacent boundary. Second, the external surface of occluded region is constructed and modeled according to the occlusion boundary and the nether adjacent boundary. Third, the observation direction, observation center point, and area information of external surface of occluded region are solved. And then, the set of candidate observation directions and the visual space of each candidate direction are determined. Finally, the next best view is achieved by solving the next best observation direction and camera’s observation position. The proposed approach does not need the prior knowledge of visual object or limit the camera position on a specially appointed surface. Experimental results demonstrate that the approach is feasible and effective.

  13. Spectrophotometric determination of etamsylate in pharmaceuticals using ferric chloride based on complex formation reactions

    Directory of Open Access Journals (Sweden)

    Kanakapura Basavaiah Vinay

    2010-03-01

    Full Text Available The present study describes two simple and selective spectrophotometric methods for the rapid determination of etamsylate (ETM in bulk and in capsule formulations. The methods are based on the oxidation of ETM with ferric chloride in neutral medium and subsequent chelation of the resulting iron(II with 1,10-phenanthroline (Phen (method A and with 2,2’-bipyridyl (Bipy (method B. The resulting red colored chromogens are measured at 510 and 520 nm, in method A and B, respectively. In both methods, the absorbance is found to increase linearly with increasing ETM concentration. Beer’s law is obeyed over the ranges 0.5-10 and 0.8-16 µg/ml for method A and B, respectively. The calculated molar absorptivity values are 2.17x104 and 1.65x104 l mol-1 cm-1 for method A and B, respectively, and the corresponding sandell sensitivities are 0.012 and 0.016 µg/cm2. Intra-day and inter-day precision and accuracy of the methods were established according to ICH guidelines. The proposed methods were applied to determine ETM in dosage forms and the results were statistically compared with that of an official BP method

  14. Selective spectrophotometric determination of TNT using a dicyclohexylamine-based colorimetric sensor.

    Science.gov (United States)

    Erçağ, Erol; Uzer, Ayşem; Apak, Reşat

    2009-05-15

    Because of the extremely heterogeneous distribution of explosives in contaminated soils, on-site colorimetric methods are efficient tools to assess the nature and extent of contamination. To meet the need for rapid and low-cost chemical sensing of explosive traces or residues in soil and post-blast debris, a colorimetric absorption-based sensor for trinitrotoluene (TNT) determination has been developed. The charge-transfer (CT) reagent (dicyclohexylamine, DCHA) is entrapped in a polyvinylchloride (PVC) polymer matrix plasticised with dioctylphtalate (DOP), and moulded into a transparent sensor membrane sliced into test strips capable of sensing TNT showing an absorption maximum at 530 nm when placed in a 1-mm spectrophotometer cell. The sensor gave a linear absorption response to 5-50 mg L(-1) TNT solutions in 30% aqueous acetone with limit of detection (LOD): 3 mg L(-1). The sensor is only affected by tetryl, but not by RDX, pentaerythritoltetranitrate (PETN), dinitrotoluene (DNT), and picric acid. The proposed method was statistically validated for TNT assay against high performance liquid chromatography (HPLC) using a standard sample of Comp B. The developed sensor was relatively resistant to air and water, was of low-cost and high specificity, gave a rapid and reproducible response, and was suitable for field use of TNT determination in both dry and humid soil and groundwater with a portable colorimeter.

  15. Determination of triacyl glycerol and sterol components of fat to authenticate ghee based sweets.

    Science.gov (United States)

    Kala, A L Amrutha; Sabeena, K; Havanur, Priya Pramod

    2016-04-01

    Method comparison of triacyl glycerol (TAG) and sterol components of fats of ghee based sweets was carried out on dairy ghee, laboratory prepared control sample and market samples. The fat was extracted from control and market samples. Determination of TAG and sterol composition of the fats was carried out using low resolution Gas Chromatography. The quantification of cholesterol and β-sitosterol and TAG classes of dairy ghee, control and market samples fat was also determined using single short column. Adulteration at 5 % level in milk fats showed varied TAG compositions of C50, C52 and C54 as compared to control and pure ghee sample. The cholesterol content of ghee and control sample was 2.30 ± 0.8, 2.00 ± 0.24 g/kg respectively and β-sitosterol content of control was 0.20 ± 0.11 g/kg. The adulterated samples showed varied cholesterol and β-sitosterol contents as compared to control sample fat.

  16. 41Ca ultratrace determination with isotopic selectivity > 10(12) by diode-laser-based RIMS.

    Science.gov (United States)

    Müller, P; Bushaw, B A; Blaum, K; Diel, S; Geppert, C; Nähler, A; Trautmann, N; Nörtershäuser, W; Wendt, K

    2001-07-01

    41Ca ultratrace determination by diode-laser-based resonance ionization mass spectrometry with extremely high isotopic selectivity is presented. Application to environmental dosimetry of nuclear reactor components, to cosmochemical investigations of production cross sections, and biomedical isotope-tracer studies of human calcium kinetics are discussed. Future investigations are possible use in 41Ca-radiodating. Depending on the application, 41Ca isotopic abundances in the range of 10(-9) to 10(-15) relative to the dominant stable isotope 40Ca must be determined. Either double- or triple-resonance optical excitation with narrow-band extended cavity diode lasers and subsequent non-resonant photoionization of calcium in a collimated atomic beam were used. The resulting photoions are detected with a quadrupole mass spectrometer optimized for background reduction and neighboring mass suppression. Applying the full triple-resonance scheme provides a selectivity of approximately 5 x 10(12) in the suppression of neighboring isotopes and > 10(8) for isobars, together with an overall detection efficiency of approximately 5 x 10(-5). Measurements on a variety of sample types are discussed; the accuracy and reproducibility of the resulting 41Ca/40Ca isotope ratios was better than 5%.

  17. A method to determine the mechanical properties of the retina based on an experiment in vivo.

    Science.gov (United States)

    Qian, Xiuqing; Zhang, Kunya; Liu, Zhicheng

    2015-01-01

    A method is proposed to determine the mechanical properties of retina based on in vivo experiments and numerical simulations. First, saline water was injected into the anterior chamber of the right eye of a cat to cause acute high intraocular pressure. After the eye was scanned using optical coherence tomography under different acute high intraocular pressures, the images of the retina in vivo were obtained and the thickness of the retina was calculated. Then, the three-dimensional structure of the optic nerve head including the retina and the choroid were reconstructed using image processing technology. Three different material models for the retina and the choroid were taken and the finite element models of the optic nerve head were constructed. Finally, an inverse method was proposed to determine the parameters of a constitutive model of the retina and of the choroid simultaneously. The results showed that the deformation of the retina can be properly simulated taking into consideration the nonlinear elastic properties of the retina and of the choroid.

  18. Using pharmacoeconomic modelling to determine value-based pricing for new pharmaceuticals in malaysia.

    Science.gov (United States)

    Dranitsaris, George; Truter, Ilse; Lubbe, Martie S; Sriramanakoppa, Nitin N; Mendonca, Vivian M; Mahagaonkar, Sangameshwar B

    2011-10-01

    Decision analysis (DA) is commonly used to perform economic evaluations of new pharmaceuticals. Using multiples of Malaysia's per capita 2010 gross domestic product (GDP) as the threshold for economic value as suggested by the World Health Organization (WHO), DA was used to estimate a price per dose for bevacizumab, a drug that provides a 1.4-month survival benefit in patients with metastatic colorectal cancer (mCRC). A decision model was developed to simulate progression-free and overall survival in mCRC patients receiving chemotherapy with and without bevacizumab. Costs for chemotherapy and management of side effects were obtained from public and private hospitals in Malaysia. Utility estimates, measured as quality-adjusted life years (QALYs), were determined by interviewing 24 oncology nurses using the time trade-off technique. The price per dose was then estimated using a target threshold of US$44 400 per QALY gained, which is 3 times the Malaysian per capita GDP. A cost-effective price for bevacizumab could not be determined because the survival benefit provided was insufficient According to the WHO criteria, if the drug was able to improve survival from 1.4 to 3 or 6 months, the price per dose would be $567 and $1258, respectively. The use of decision modelling for estimating drug pricing is a powerful technique to ensure value for money. Such information is of value to drug manufacturers and formulary committees because it facilitates negotiations for value-based pricing in a given jurisdiction.

  19. Development of an immunochromatographic assay based on carbon nanoparticles for the determination of the phytoregulator forchlorfenuron.

    Science.gov (United States)

    Suárez-Pantaleón, Celia; Wichers, Jan; Abad-Somovilla, Antonio; van Amerongen, Aart; Abad-Fuentes, Antonio

    2013-04-15

    Rapid analytical methods enabling the determination of diverse targets are essential in a number of research areas, from clinical diagnostics to feed and food quality and safety. Herein, the development of a quantitative immunochromatographic assay for the detection of the synthetic phytoregulator forchlorfenuron (CPPU) is described. The competitive lateral flow immunoassay (LFIA) was based on the immobilization onto a nitrocellulose membrane of an ovalbumin-CPPU conjugate (test line) and on the use of an immunodetection ligand consisting of carbon nanoparticles labeled with an anti-CPPU monoclonal antibody through interaction with a secondary antibody. The presence of CPPU in horticultural samples was visually interpreted by the decrease in the black signal intensity of the test line, according to the competitive character of the format. The quantitative determination of the analyte was easily performed by a two-step procedure consisting of flatbed scanning of the strips followed by computer-based image analysis of the pixel gray volumes of the test lines. Under optimized conditions, the immunochromatographic test afforded a limit of quantification in buffer of 89 ng/L. The accuracy of the strip test was assessed by the analysis of fruit samples with incurred residues, and the obtained results were compared with those derived from two reference methods, ELISA and HPLC. The LOQ of the CPPU-specific LFIA in kiwifruits and grapes was established at 33.4 μg/kg. The excellent analytical performance of the developed strip test demonstrates the potential of immunochromatographic assays for the quantitative monitoring of small organic molecules in complex matrices. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Equation-free analysis of agent-based models and systematic parameter determination

    Science.gov (United States)

    Thomas, Spencer A.; Lloyd, David J. B.; Skeldon, Anne C.

    2016-12-01

    Agent based models (ABM)s are increasingly used in social science, economics, mathematics, biology and computer science to describe time dependent systems in circumstances where a description in terms of equations is difficult. Yet few tools are currently available for the systematic analysis of ABM behaviour. Numerical continuation and bifurcation analysis is a well-established tool for the study of deterministic systems. Recently, equation-free (EF) methods have been developed to extend numerical continuation techniques to systems where the dynamics are described at a microscopic scale and continuation of a macroscopic property of the system is considered. To date, the practical use of EF methods has been limited by; (1) the over-head of application-specific implementation; (2) the laborious configuration of problem-specific parameters; and (3) large ensemble sizes (potentially) leading to computationally restrictive run-times. In this paper we address these issues with our tool for the EF continuation of stochastic systems, which includes algorithms to systematically configuration problem specific parameters and enhance robustness to noise. Our tool is generic and can be applied to any 'black-box' simulator and determines the essential EF parameters prior to EF analysis. Robustness is significantly improved using our convergence-constraint with a corrector-repeat (C3R) method. This algorithm automatically detects outliers based on the dynamics of the underlying system enabling both an order of magnitude reduction in ensemble size and continuation of systems at much higher levels of noise than classical approaches. We demonstrate our method with application to several ABM models, revealing parameter dependence, bifurcation and stability analysis of these complex systems giving a deep understanding of the dynamical behaviour of the models in a way that is not otherwise easily obtainable. In each case we demonstrate our systematic parameter determination stage for

  1. Validated spectrophotometric methods for determination of sodium valproate based on charge transfer complexation reactions.

    Science.gov (United States)

    Belal, Tarek S; El-Kafrawy, Dina S; Mahrous, Mohamed S; Abdel-Khalek, Magdi M; Abo-Gharam, Amira H

    2016-02-15

    This work presents the development, validation and application of four simple and direct spectrophotometric methods for determination of sodium valproate (VP) through charge transfer complexation reactions. The first method is based on the reaction of the drug with p-chloranilic acid (p-CA) in acetone to give a purple colored product with maximum absorbance at 524nm. The second method depends on the reaction of VP with dichlone (DC) in dimethylformamide forming a reddish orange product measured at 490nm. The third method is based upon the interaction of VP and picric acid (PA) in chloroform resulting in the formation of a yellow complex measured at 415nm. The fourth method involves the formation of a yellow complex peaking at 361nm upon the reaction of the drug with iodine in chloroform. Experimental conditions affecting the color development were studied and optimized. Stoichiometry of the reactions was determined. The proposed spectrophotometric procedures were effectively validated with respect to linearity, ranges, precision, accuracy, specificity, robustness, detection and quantification limits. Calibration curves of the formed color products with p-CA, DC, PA and iodine showed good linear relationships over the concentration ranges 24-144, 40-200, 2-20 and 1-8μg/mL respectively. The proposed methods were successfully applied to the assay of sodium valproate in tablets and oral solution dosage forms with good accuracy and precision. Assay results were statistically compared to a reference pharmacopoeial HPLC method where no significant differences were observed between the proposed methods and reference method. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. A Rejection Sampling Based Method for Determining Thermal Scattering Angle and Energy

    Energy Technology Data Exchange (ETDEWEB)

    Haugen, Carl C.; Forget, Benoit; Smith, Kord S.

    2017-09-01

    Most high performance computing systems being deployed currently and envisioned for the future are based on making use of heavy parallelism across many computational nodes and many concurrent cores. These types of heavily parallel systems often have relatively little memory per core but large amounts of computing capability. This places a significant constraint on how data storage is handled in many Monte Carlo codes. This is made even more significant in fully coupled multiphysics simulations, which requires simulations of many physical phenomena be carried out concurrently on individual processing nodes, which further reduces the amount of memory available for storage of Monte Carlo data. As such, there has been a move towards on-the-fly nuclear data generation to reduce memory requirements associated with interpolation between pre-generated large nuclear data tables for a selection of system temperatures. Methods have been previously developed and implemented in MIT’s OpenMC Monte Carlo code for both the resolved resonance regime and the unresolved resonance regime, but are currently absent for the thermal energy regime. While there are many components involved in generating a thermal neutron scattering cross section on-the-fly, this work will focus on a proposed method for determining the energy and direction of a neutron after a thermal incoherent inelastic scattering event. This work proposes a rejection sampling based method using the thermal scattering kernel to determine the correct outgoing energy and angle. The goal of this project is to be able to treat the full S (a, ß) kernel for graphite, to assist in high fidelity simulations of the TREAT reactor at Idaho National Laboratory. The method is, however, sufficiently general to be applicable in other thermal scattering materials, and can be initially validated with the continuous analytic free gas model.

  3. Determination of L- and D-fucose using amperometric electrodes based on diamond paste.

    Science.gov (United States)

    Stefan-van Staden, Raluca-Ioana; Nejem, R'afat Mahmoud; van Staden, Jacobus Frederick; Aboul-Enein, Hassan Y

    2012-02-21

    Monocrystalline diamond (natural diamond, synthetic-1 and synthetic-2) based electrochemical electrodes were designed for the analysis of L- and D-fucose. Response characteristics of the electrochemical electrodes were determined using cyclic voltammetry and differential pulse voltammetry (DPV). L-fucose was determined using DPV with electrodes based on natural diamond, synthetic-1 and synthetic-2, respectively, at 240 mV using NaCl as the electrolyte (pH 3.0); at 160 mV using KNO(3) (pH 10.0) and at 80 mV using KCl as the electrolyte (pH 10.0) while D-fucose was analyzed at 120 mV using KCl as the electrolyte (pH 1.0); at 140 mV using KNO(3) as the electrolyte (pH 1.0) and at 160 mV using NaNO(3) as the electrolyte (pH 3.0). The linear concentration ranges for L-fucose were between 10(-13) and 10(-9) mol L(-1) (natural diamond), 10(-11) and 10(-8) mol L(-1) (synthetic-1) and 10(-6) and 10(-3) mol L(-1) (synthetic-2) with detection limits of 10(-14), 10(-12) and 10(-8) mol L(-1) magnitude order, respectively. For D-fucose, the linear concentration ranges were 10(-6) to 10(-3) mol L(-1) (natural diamond), 10(-5) to 10(-3) mol L(-1) (synthetic-1) and 10(-9) to 10(-3) mol L(-1) (synthetic-2) with detection limits of 10(-7), 10(-7) and 10(-10) mol L(-1) magnitude order, respectively. The sensors were used for the assay of L-fucose in serum and urine samples.

  4. Base-pairing versatility determines wobble sites in tRNA anticodons of vertebrate mitogenomes.

    Directory of Open Access Journals (Sweden)

    Miguel M Fonseca

    Full Text Available BACKGROUND: Vertebrate mitochondrial genomes typically have one transfer RNA (tRNA for each synonymous codon family. This limited anticodon repertoire implies that each tRNA anticodon needs to wobble (establish a non-Watson-Crick base pairing between two nucleotides in RNA molecules to recognize one or more synonymous codons. Different hypotheses have been proposed to explain the factors that determine the nucleotide composition of wobble sites in vertebrate mitochondrial tRNA anticodons. Until now, the two major postulates--the "codon-anticodon adaptation hypothesis" and the "wobble versatility hypothesis"--have not been formally tested in vertebrate mitochondria because both make the same predictions regarding the composition of anticodon wobble sites. The same is true for the more recent "wobble cost hypothesis". PRINCIPAL FINDINGS: In this study we have analyzed the occurrence of synonymous codons and tRNA anticodon wobble sites in 1553 complete vertebrate mitochondrial genomes, focusing on three fish species with mtDNA codon usage bias reversal (L-strand is GT-rich. These mitogenomes constitute an excellent opportunity to study the evolution of the wobble nucleotide composition of tRNA anticodons because due to the reversal the predictions for the anticodon wobble sites differ between the existing hypotheses. We observed that none of the wobble sites of tRNA anticodons in these unusual mitochondrial genomes coevolved to match the new overall codon usage bias, suggesting that nucleotides at the wobble sites of tRNA anticodons in vertebrate mitochondrial genomes are determined by wobble versatility. CONCLUSIONS/SIGNIFICANCE: Our results suggest that, at wobble sites of tRNA anticodons in vertebrate mitogenomes, selection favors the most versatile nucleotide in terms of wobble base-pairing stability and that wobble site composition is not influenced by codon usage. These results are in agreement with the "wobble versatility hypothesis".

  5. Quality of life and its determinants in postmenopausal women: a population-based study.

    Science.gov (United States)

    Mirhaghjou, Seyedeh Nooshaz; Niknami, Maryam; Moridi, Maryam; Pakseresht, Sedigheh; Kazemnejad, Ehsan

    2016-05-01

    This study aimed to assess quality of life (QOL) and its determinants in Iranian postmenopausal women. This population-based cross-sectional survey was conducted using cluster sampling design. The samples consisted of postmenopausal women aged 40-60 years with total household in Rasht city (north Iran) as the sample frame. Quality of life was assessed by Menopause-Specific QOL (MENQOL) Questionnaire. Mean domain scores and factors related to the higher score of each domain were determined. Findings showed that the mean scores for each domain were: vasomotor: 2.14 ± 1.49; psycho-social: 1.56 ± 0.85; physical: 1.91 ± 0.52 and sexual: 1.37 ± 1.05. Comparing the median of the studied domains, physical domain had the worst score in menopausal women. Pain in joint and muscle, one item of physical domain, had the highest score. The univariate analysis demonstrated that women aged 60-65 (p women with postmenopausal stage 5 or more years (p women (p women holding higher education degree (p women (p women with a body mass index (BMI) women who do physical activity (p < 0.05) showed better QOL. Based on Logistic Regression model, the predictive factors of normal QOL in menopause status were: age, husband education, score of Charlson Comorbidity Index (CCI) and BMI. Our findings suggest that menopause-related symptoms had negative impact on QOL. Confirmation by further research is needed. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. YREE determination in seawater. Standardization and validation of a new method based on preconcentration techniques

    Science.gov (United States)

    Raso, Maria; Saiano, Filippo; Montalbano, Maria; Censi, Paolo

    2010-05-01

    The most interesting attraction of using rare-earth elements and yttrium (YREE) to address geochemical and marine chemical problems consists of their chemical coherence as group of trace elements. These characters allow YREE compositions of rocks and minerals to be extensively used in studies of provenance, petrogenesis and chemical evolution of the geological materials (1). Similarly, YREE compositions in the hydrosphere were used in studies of coagulation, particle-solution reactions and oceanic circulation of water masses (2-4). Unfortunately, very low concentrations of YREE (ng l-1 or sub-ng l-1) associated to high ionic strength of seawater always represented the main difficulty to analyse dissolved YREE in marine environment. The first geochemical investigations of YREE contents in seawater were carried out using neutron activation and isotope dilution mass spectrometry that were almost entirely replaced by inductively coupled plasma supplemented by mass spectrometry (ICP-MS) in recent years. This technique offers many advantages including simultaneous analysis of all the elements of series and their quantitative determination with detection limits of the order of ng l-1 if associated to preconcentration techniques (5). To perform ultra-trace YREE analyses in seawater, we developed a preconcentration method based on CHELEX-100 iminodiacetate resin followed by ICP-MS determination (Ref). In this study the YREE behaviour was quantitatively investigated during interactions with ion chelating resin and estimation of composed measurement uncertainty associated to measurements was evaluated with a rigorous metrological approach based on method validation and quality control of YREE data. These goals were achieved using synthetic seawater where YREE had concentrations as occurring in natural seawater samples. Under these conditions good recovery were obtained along the YREE series, ranging from 75%-85% and 90%-100% for heavy REE and Y and light REE, respectively

  7. Determining the Onset of Turbulent Flow Using Video Based Motion Analysis

    Science.gov (United States)

    Barton, Robert; Lemley, Corey; French, Paul

    2007-04-01

    Recent advancements in computing technology have drastically improved the interface between computers and video equipment, thus allowing for the improvement of video-based motion analysis. However, analysis of video data remains susceptible to errors caused by lens distortion, angular distortion, descaling, and discretization. In previous work, methods were developed to correct for some of these errors. This paper presents several improvements to these corrections, as well as additional methods to increase accuracy, including: 1) improvement of the measurement of lens distortion, 2) automation of the lens distortion correction technique, 3) a simulation method to test the correction of lens distortion error, 4) creation of an algorithm to correct for angular distortion, and 5) refinement of a two camera system to correct for descaling error. The methods were tested in the context of the measurement of the air resistance force on a high-speed projectile. This allowed for the determination of the onset of turbulent flow. These significant improvements in accuracy have made video-based analysis an even more powerful tool for the study of motion.

  8. Simultaneous determination of five Alternaria toxins in cereals using QuEChERS-based methodology.

    Science.gov (United States)

    Zhou, Jian; Xu, Jiao-Jiao; Cai, Zeng-Xuan; Huang, Bai-Fen; Jin, Mi-Cong; Ren, Yi-Ping

    2017-11-15

    Two analytical approaches, including ultra-high performance liquid chromatograph linked with photo-diode array/fluorescence detector, and ultra-high performance liquid chromatography-tandem mass spectrometry, have been proposed for simultaneous determination of five Alternaria toxins in cereals, which both based on QuEChERS strategy. After QuEChERS extraction and salting out, the collected supernatant was subjected to an extra dispersive liquid-liquid microextraction step prior to quantitative analysis. Response surface methodology based on central composite design was employed to optimize the micro-extraction conditions. During photo-diode array/fluorescence detector method validation, satisfactory analytical characteristics, in terms of selectivity, recovery (72.7%-109.1%), precision (inter-day RSDs <9.6%), sensitivity (limits of quantification ranged from 2.1μgkg -1 to 120.0μgkg -1 ) and linearity (R 2 all higher than 0.9984), were achieved. Mass spectrometry method was employed as a certified method for accuracy. The two methodologies were successfully applied to 71 samples including three different matrices and the quantitative results were compared. As the result of non-parametric test shown, the established two analytical approach exhibited comparable quantitative accuracy to each other. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Combining Regional Monitoring Stations with Space-based Data to Determine the MEO Satellite Orbit

    Directory of Open Access Journals (Sweden)

    WANG Le

    2017-05-01

    Full Text Available The ground monitoring stations of BeiDou Navigation Satellite System (BDS are regional distribution and the number of these stations is small. The more global ground stations cannot be built in the short term. The ground regional monitoring stations are difficult to observe the global Medium Earth Orbit Satellite (MEO continuously, which leads to low precision of orbits in BDS real-time broadcast ephemeris. Based on the above problems, in view of real time satellite GNSS data of low earth orbit satellite can effectively make up the lack of regional monitoring stations in space overlay, a method is proposed that the GNSS receivers of LEO satellites used as high dynamic space-based monitoring stations combining with the data of the ground monitoring stations to calculate and forecast the MEO satellite orbits. The numeral results show that, using the data of seven regional monitoring stations add 1 to 3 LEO satellites, the precision of the MEO orbit determination can be increased by about 21%, 34% and 55% respectively. It also shows that, the ground regional monitoring stations combined with the data of LEO satellites can effectively improve the orbit precision of MEO satellite. It is suggested that using the data combined with ground stations and LEO satellites to improve the precision of broadcast ephemeris of MEO in BDS.

  10. A Monoclonal Antibody-Based ELISA for Multiresidue Determination of Avermectins in Milk

    Directory of Open Access Journals (Sweden)

    Wenxiao Jiang

    2012-06-01

    Full Text Available Due to the widespread use and potential toxicity of avermectins (AVMs, multi-residue monitoring of AVMs in edible tissues, especially in milk, has become increasingly important. With the aim of developing a broad-selective immunoassay for AVMs, a broad-specific monoclonal antibody (Mab was raised. Based on this Mab, a homologous indirect enzyme-linked immunosorbent assay (ELISA for the rapid detection of AVMs in milk was developed. Under the optimized conditions, the IC50 values in assay buffer were estimated to be 3.05 ng/mL for abamectin, 13.10 ng/mL for ivermectin, 38.96 ng/mL for eprinomectin, 61.00 ng/mL for doramectin, 14.38 ng/mL for emamectin benzoate. Detection capability (CCβ of the ELISA was less than 5 ng/mL and 2 ng/mL in milk samples prepared by simple dilution and solvent extraction, respectively. The optimized ELISA was used to quantify AVMs in milk samples spiked at different amounts. The mean recovery and coefficient of variation (CV were 95.90% and 15.42%, respectively. The Mab-based ELISA achieved a great improvement in AVMs detection. Results proved this broad-selective ELISA would be useful for the multi-residue determination of AVMs in milk without purification process.

  11. Positional accuracy in RPC point determination based on high-resolution imagery

    Science.gov (United States)

    Meng, Han; Liu, Yongliang; Zhang, Jingxiong; Gong, Hao

    2007-06-01

    The rational function model (RFM), also known as rational polynomial coefficients (RPCs) or rational polynomial camera (RPC) model, is a generalized sensor model. Different from rigorous sensor model, RFM does not need to obtain the interior and exterior orientation geometry and other physical properties associated with the physical sensor. RFMs were first adopted by Space Imaging company as a replacement for rigorous sensor models, and it drew much attention from the commercial satellite data vendors who rapidly followed the suit in order to protect the confidential information of the sensors. This paper focuses on the solution for rational polynomial coefficients, RFM-based stereo-model reconstitution, and positional accuracy analysis. As RPCs do not have obvious physical meanings and their solution is iterative, analytical approaches to accuracy analysis may not be feasible; computer simulation is thus adopted to quantify accuracy in RPC-determined positional data. The simulation-based strategy is efficient in mapping local features in positional errors, which contain both the systematic and random components.

  12. Electric field strength determination in filamentary DBDs by CARS-based four-wave mixing

    Science.gov (United States)

    Boehm, Patrick; Kettlitz, Manfred; Brandenburg, Ronny; Hoeft, Hans; Czarnetzki, Uwe

    2016-09-01

    The electric field strength is a basic parameter of non-thermal plasmas. Therefore, a profound knowledge of the electric field distribution is crucial. In this contribution a four wave mixing technique based on Coherent Anti-Stokes Raman spectroscopy (CARS) is used to measure electric field strengths in filamentary dielectric barrier discharges (DBDs). The discharges are operated with a pulsed voltage in nitrogen at atmospheric pressure. Small amounts hydrogen (10 vol%) are admixed as tracer gas to evaluate the electric field strength in the 1 mm discharge gap. Absolute values of the electric field strength are determined by calibration of the CARS setup with high voltage amplitudes below the ignition threshold of the arrangement. Alteration of the electric field strength has been observed during the internal polarity reversal and the breakdown process. In this case the major advantage over emission based methods is that this technique can be used independently from emission, e.g. in the pre-phase and in between two consecutive, opposite discharge pulses where no emission occurs at all. This work was supported by the Deutsche Forschungsgemeinschaft, Forschergruppe FOR 1123 and Sonderforschungsbereich TRR 24 ``Fundamentals of complex plasmas''.

  13. Determination of full piezoelectric complex parameters using gradient-based optimization algorithm

    Science.gov (United States)

    Kiyono, C. Y.; Pérez, N.; Silva, E. C. N.

    2016-02-01

    At present, numerical techniques allow the precise simulation of mechanical structures, but the results are limited by the knowledge of the material properties. In the case of piezoelectric ceramics, the full model determination in the linear range involves five elastic, three piezoelectric, and two dielectric complex parameters. A successful solution to obtaining piezoceramic properties consists of comparing the experimental measurement of the impedance curve and the results of a numerical model by using the finite element method (FEM). In the present work, a new systematic optimization method is proposed to adjust the full piezoelectric complex parameters in the FEM model. Once implemented, the method only requires the experimental data (impedance modulus and phase data acquired by an impedometer), material density, geometry, and initial values for the properties. This method combines a FEM routine implemented using an 8-noded axisymmetric element with a gradient-based optimization routine based on the method of moving asymptotes (MMA). The main objective of the optimization procedure is minimizing the quadratic difference between the experimental and numerical electrical conductance and resistance curves (to consider resonance and antiresonance frequencies). To assure the convergence of the optimization procedure, this work proposes restarting the optimization loop whenever the procedure ends in an undesired or an unfeasible solution. Two experimental examples using PZ27 and APC850 samples are presented to test the precision of the method and to check the dependency of the frequency range used, respectively.

  14. Determining the mechanical properties of a radiochromic silicone-based 3D dosimeter

    Science.gov (United States)

    Kaplan, L. P.; Høye, E. M.; Balling, P.; Muren, L. P.; Petersen, J. B. B.; Poulsen, P. R.; Yates, E. S.; Skyt, P. S.

    2017-07-01

    New treatment modalities in radiotherapy (RT) enable delivery of highly conformal dose distributions in patients. This creates a need for precise dose verification in three dimensions (3D). A radiochromic silicone-based 3D dosimetry system has recently been developed. Such a dosimeter can be used for dose verification in deformed geometries, which requires knowledge of the dosimeter’s mechanical properties. In this study we have characterized the dosimeter’s elastic behaviour under tensile and compressive stress. In addition, the dose response under strain was determined. It was found that the dosimeter behaved as an incompressible hyperelastic material with a non-linear stress/strain curve and with no observable hysteresis or plastic deformation even at high strains. The volume was found to be constant within a 2% margin at deformations up to 60%. Furthermore, it was observed that the dosimeter returned to its original geometry within a 2% margin when irradiated under stress, and that the change in optical density per centimeter was constant regardless of the strain during irradiation. In conclusion, we have shown that this radiochromic silicone-based dosimeter’s mechanical properties make it a viable candidate for dose verification in deformable 3D geometries.

  15. Transmission Power Determination Based on Power Amplifier Operations in Large-Scale MIMO-OFDM Systems

    Directory of Open Access Journals (Sweden)

    Byung Moo Lee

    2017-07-01

    Full Text Available This paper presents a method to determine transmission power based on power amplifier (PA operations in order to improve the energy efficiency (EE of a large-scale (LS Multiple Input Multiple Output (MIMO-OFDM system, which is a multi-carrier multiple antenna system with a large amount of transmitter (TX antennas. Regarding the EE improvement, we propose two kinds of PA operation schemes: increasing the effective TX power (ITXP and reducing the PA power consumption (RPC assuming that a reduction of peak-to-average power ratio is applied in the appropriate manner. Closed-form expressions of relative EE are derived for both schemes, and the relative EE of the ITXP scheme is shown to depend on the precoding method that is applied to reduce the inter-user interference, while that of the RPC scheme is independent of the precoding method. The relative EE difference between the ITXP and the RPC schemes is also shown to rely on the occupation ratio of the PA power consumption over the total power consumption. Thus, the EE can remarkably improve by selecting the appropriate scheme based on the circumstances. The results of a simulation also validate the derived closed-form expression of the relative EE.

  16. Manufacturing of Dysprosium-Iron Alloys by Electrolysis in Fluoride-Based Electrolytes: Oxide Solubility Determinations

    Science.gov (United States)

    Martinez, Ana Maria; Støre, Anne; Osen, Karen Sende

    2017-12-01

    Electrolytic production of light rare earth elements and alloys takes place in a fluoride-based electrolyte using rare earth oxides as raw material. The optimization of this method, mainly in terms of the energy efficiency and environmental impact control, is rather challenging. Anode effects, evolution of fluorine-containing compounds, and side cathode reactions could largely be minimized by a good control of the amount of rare earth oxide species dissolved in the fluoride-based electrolyte and their dissolution rate. The oxide content of the fluoride melts REF3-LiF (RE = Nd, Dy) at different compositions and temperatures were experimentally determined by carbothermal analysis of melt samples. The highest solubility values of oxide species, added as Dy2O3 and Dy2(CO3)3, were obtained to be of ca. 3 wt pct (expressed as Dy2O3) in the case of the equimolar DyF3-LiF melt at 1323 K (1050 °C). The oxide saturation values increased with the amount of REF3 present in the molten bath and the working temperature.

  17. A spectrofluorimetric sensor based on grape skin tissue for determination of iron(III

    Directory of Open Access Journals (Sweden)

    Minghui Zhang

    2010-04-01

    Full Text Available A spectrofluorimetric method based on the grape skin has been developed for the determination of Fe3+ at pH 5.0. The emission wavelength of the grape skin sensor occurs at 680 nm and the excitation wavelength at 421 nm. The fluorescence of sensor could be quenched by Fe3+ due to the complexing ability of anthocyanin with the metal ions. Anthocyanin, the main pigment in the grape skin, has been found fluorescence sensing material. The sensor based on the grape skin exhibited a calibration response for Fe3+ in two concentration ranges of 1.0 × 10-8 - 1.0 × 10-5 M (r2 = 0.9888 and 3.2 × 10-5 - 3.2 × 10-4 (r2 = 0.9856 M at 60 oC. The detection limit was found to be 7.5×10-9 M, and the other common ions did not interfere.

  18. Fluorescence-based determination of the copper concentration in drinking water

    Science.gov (United States)

    Hötzer, Benjamin; Scheu, Timo; Jung, Gregor; Castritius, Stefan

    2013-05-01

    Copper is a heavy metal, which is used in heat and electrical conductors and in a multitude of alloys in the technical context. Moreover, it is a trace element that is essential for the life of organisms but can cause toxic effects in elevated concentrations. Maximum limits in water and beverages exist. Here, the decrease of the fluorescence lifetime of green fluorescent protein (GFP) by Förster resonance energy transfer is used to measure the copper ion concentration in drinking water. Therefore, a system is developed that is based on a GFP sample in a predefined concentration. The GFP mutant can be excited with blue light. For binding of copper ions, a His-tag is included in the GFP. After measuring the fluorescence lifetime of pure GFP, the copper determination of the sample is performed by lifetime measurement. Therefore, the lifetime can be assigned to the copper concentration of the GFP-doped drinking water sample. In summary, a method for the quantification of copper ions based on changes of the fluorescence lifetime of GFP is developed, and the measurement of the copper concentration in water samples is performed.

  19. Fragment-based identification of determinants of conformational and spectroscopic change at the ricin active site

    Directory of Open Access Journals (Sweden)

    Soares Alexei S

    2007-11-01

    Full Text Available Abstract Background Ricin is a potent toxin and known bioterrorism threat with no available antidote. The ricin A-chain (RTA acts enzymatically to cleave a specific adenine base from ribosomal RNA, thereby blocking translation. To understand better the relationship between ligand binding and RTA active site conformational change, we used a fragment-based approach to find a minimal set of bonding interactions able to induce rearrangements in critical side-chain positions. Results We found that the smallest ligand stabilizing an open conformer of the RTA active site pocket was an amide group, bound weakly by only a few hydrogen bonds to the protein. Complexes with small amide-containing molecules also revealed a switch in geometry from a parallel towards a splayed arrangement of an arginine-tryptophan cation-pi interaction that was associated with an increase and red-shift in tryptophan fluorescence upon ligand binding. Using the observed fluorescence signal, we determined the thermodynamic changes of adenine binding to the RTA active site, as well as the site-specific binding of urea. Urea binding had a favorable enthalpy change and unfavorable entropy change, with a ΔH of -13 ± 2 kJ/mol and a ΔS of -0.04 ± 0.01 kJ/(K*mol. The side-chain position of residue Tyr80 in a complex with adenine was found not to involve as large an overlap of rings with the purine as previously considered, suggesting a smaller role for aromatic stacking at the RTA active site. Conclusion We found that amide ligands can bind weakly but specifically to the ricin active site, producing significant shifts in positions of the critical active site residues Arg180 and Tyr80. These results indicate that fragment-based drug discovery methods are capable of identifying minimal bonding determinants of active-site side-chain rearrangements and the mechanistic origins of spectroscopic shifts. Our results suggest that tryptophan fluorescence provides a sensitive probe for the

  20. Determination of critical nitrogen dilution curve based on stem dry matter in rice.

    Directory of Open Access Journals (Sweden)

    Syed Tahir Ata-Ul-Karim

    Full Text Available Plant analysis is a very promising diagnostic tool for assessment of crop nitrogen (N requirements in perspectives of cost effective and environment friendly agriculture. Diagnosing N nutritional status of rice crop through plant analysis will give insights into optimizing N requirements of future crops. The present study was aimed to develop a new methodology for determining the critical nitrogen (Nc dilution curve based on stem dry matter (SDM and to assess its suitability to estimate the level of N nutrition for rice (Oryza sativa L. in east China. Three field experiments with varied N rates (0-360 kg N ha(-1 using three Japonica rice hybrids, Lingxiangyou-18, Wuxiangjing-14 and Wuyunjing were conducted in Jiangsu province of east China. SDM and stem N concentration (SNC were determined during vegetative stage for growth analysis. A Nc dilution curve based on SDM was described by the equation (Nc = 2.17W(-0.27 with W being SDM in t ha(-1, when SDM ranged from 0.88 to 7.94 t ha(-1. However, for SDM < 0.88 t ha(-1, the constant critical value Nc = 1.76% SDM was applied. The curve was dually validated for N-limiting and non-N-limiting growth conditions. The N nutrition index (NNI and accumulated N deficit (Nand of stem ranged from 0.57 to 1.06 and 51.1 to -7.07 kg N ha(-1, respectively, during key growth stages under varied N rates in 2010 and 2011. The values of ΔN derived from either NNI or Nand could be used as references for N dressing management during rice growth. Our results demonstrated that the present curve well differentiated the conditions of limiting and non-limiting N nutrition in rice crop. The SDM based Nc dilution curve can be adopted as an alternate and novel approach for evaluating plant N status to support N fertilization decision during the vegetative growth of Japonica rice in east China.

  1. Auto Code Generation for Simulink-Based Attitude Determination Control System

    Science.gov (United States)

    MolinaFraticelli, Jose Carlos

    2012-01-01

    This paper details the work done to auto generate C code from a Simulink-Based Attitude Determination Control System (ADCS) to be used in target platforms. NASA Marshall Engineers have developed an ADCS Simulink simulation to be used as a component for the flight software of a satellite. This generated code can be used for carrying out Hardware in the loop testing of components for a satellite in a convenient manner with easily tunable parameters. Due to the nature of the embedded hardware components such as microcontrollers, this simulation code cannot be used directly, as it is, on the target platform and must first be converted into C code; this process is known as auto code generation. In order to generate C code from this simulation; it must be modified to follow specific standards set in place by the auto code generation process. Some of these modifications include changing certain simulation models into their atomic representations which can bring new complications into the simulation. The execution order of these models can change based on these modifications. Great care must be taken in order to maintain a working simulation that can also be used for auto code generation. After modifying the ADCS simulation for the auto code generation process, it is shown that the difference between the output data of the former and that of the latter is between acceptable bounds. Thus, it can be said that the process is a success since all the output requirements are met. Based on these results, it can be argued that this generated C code can be effectively used by any desired platform as long as it follows the specific memory requirements established in the Simulink Model.

  2. Determination of saturation functions and wettability for chalk based on measured fluid saturations

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, D.; Bech, N.; Moeller Nielsen, C.

    1998-08-01

    The end effect of displacement experiments on low permeable porous media is used for determination of relative permeability functions and capillary pressure functions. Saturation functions for a drainage process are determined from a primary drainage experiment. A reversal of the flooding direction creates an intrinsic imbibition process in the sample, which enables determination if imbibition saturation functions. The saturation functions are determined by a parameter estimation technique. Scanning effects are modelled by the method of Killough. Saturation profiles are determined by NMR. (au)

  3. A simple conductometric method for trace level determination of brilliant green in water based on β-cyclodextrin and silver nitrate and determination of their thermodynamic parameters

    Directory of Open Access Journals (Sweden)

    Roya Mohammad Zadeh Kakhki

    2014-12-01

    Full Text Available A gravimetric and complexometric titration method based on conductometric technique is presented for the quantitative determination of brilliant green (BG in water. The equilibrium constants and the thermodynamic parameters for the complex formation of β-cyclodextrin (β-CD with brilliant green (BG and precipitation of silver nitrate with BG have been determined by conductivity measurements in water. The results suggest that stable 1:1 complex is formed between BG and β-cyclodextrin and the thermodynamic parameters (ΔHc°,ΔSc° for this complexation reaction have been determined from temperature dependence of the stability constant using the van’t Hoff plots. Based on the obtained results, the conductometric method for the determination of BG in the presence of β-CD at 25 °C was developed in the range of 10−8–10−3 molL−1 and with AgNO3 is 10−3–10−5 molL−1.

  4. Room temperature phosphorimetric determination of bromate in flour based on energy transfer.

    Science.gov (United States)

    Menendez-Miranda, Mario; Fernandez-Argüelles, Maria T; Costa-Fernandez, Jose M; Pereiro, Rosario; Sanz-Medel, Alfredo

    2013-11-15

    Determination of bromate ions in contaminated flour samples by using a room temperature phosphorescence (RTP) optosensor is described. The optosensor is based on the non-radiative energy transfer from α-bromonaphthalene (a phosphorescent molecule insensitive to the presence of the analyte) acting as donor, to an energy acceptor bromate-sensitive molecule (trifluoperazine hydrochloride). The RTP emission of the selected donor greatly overlaps with the absorption spectrum of the acceptor, resulting in a decrease of the measured signal as the concentration of bromate ions increases. A simple and general procedure is proposed to carry out the incorporation of both the donor and acceptor molecules in an appropriate solid material (sensing phase) through the co-immobilization of the species in a sol-gel inorganic matrix. The optimum amounts of the sol-gel precursors, including silica precursors, type of catalysis, and concentrations of donor and acceptor molecules, have been evaluated in order to obtain the best analytical features of the proposed optosensor for bromate determination. The highly stable developed sensing phase shows a selective and reversible response towards bromate even in presence of dissolved oxygen (a well-known quencher of the RTP). The calibration graphs were linear up to 200 mg L(-1), with a detection limit for bromate dissolved in aqueous medium of 0.2 mg L(-1). Sample throughput of the proposed optosensor was about 18 measurements h(-1). Application of the developed sensing phase was successfully proved for the detection of bromate ions in commercial flours, obtaining good recoveries. © 2013 Elsevier B.V. All rights reserved.

  5. A study on determining the needs of gifted individuals based on parental views

    Directory of Open Access Journals (Sweden)

    Eda Gürlen

    2017-09-01

    Full Text Available Ensuring that gifted individuals receive differentiated and enhanced education, which is suitable for their areas of skills and developmental characteristics, will contribute to revealing their skills and developing their multiple developmental areas to bring them to upper levels. The purpose of this study is to determine the needs of gifted individuals by developing a curriculum which considers their educational needs. In the scope of this study, interviews were made with ten parents using the Snowball Sapling Method. The questionnaires used in the interviews were prepared in a semi-structured manner in light of variables determined from the literature on the subject . Interviews were made by two researchers. The two researchers assessed data obtained separately; and thus, codes of study were obtained. Themes were formed according to common components of the codes. Three main themes were formed on needs analysed in light of data obtained from the literature on the topic. These themes were “Characteristics of Gifted Individuals”; “School and Expectations from It”; and “Being Parents of Gifted Individuals”. These themes were separated into sub-themes. The parents explained “different behaviour patterns of their gifted children”, “characteristic of their children” and “situations their gifted children like/do not like” in the “Characteristics of Gifted Individuals” theme.The “School and Expectations from It” theme consisted of two sub-themes, which were “satisfaction of parents with school”, and “expectations of parents from school”. In the “Being Parents of Gifted Individuals” theme, the parents explained, “their concerns ”, “their regrets”, “the difficulties they have with their children”, and “their complaints”. Results of this study led to initialising a curriculum development study for gifted children which is based on their characteristics and needs.

  6. Determination of Magnet Specification of 13 MeV Proton Cyclotron Based on Opera 3D

    Directory of Open Access Journals (Sweden)

    Taufik

    2014-08-01

    Full Text Available The magnet is one of the main components of a cyclotron, used to form a circular particle beam trajectories and to provide focusing of the beam. To support the mastery of 13-MeV proton cyclotron technologies, cyclotron magnet design must be done to satisfy cyclotron magnet requirements. This research was conducted by studying important parameters in designing the cyclotron magnet which is then used to determine the design requirements. The magnet design was based on the results of a 3D simulation using Opera 3D software. Opera 3D is a software developed by Cobham plc to solve physical problems in 3D such as magnetostatic using finite element methods. The simulation started by drawing a 3D model of the magnet using a modeler, followed by magnetic field calculations by Tosca module in the Opera 3D software. Simulation results were analyzed with the Genspeo software to determine whether the parameters of the cyclotron magnet have met design requirements. The results indicate that the magnet design satisfied the cyclotron magnet design requirement, that B in the median plane of the magnetic pole approached the isochronous curve, providing axial and radial focusing beam, crossing the resonance line at vr = 1 when the particle energy is low and the particle energy is more than 13 MeV, and lead to small enough phase shift of about 13°. The dimension of the cyclotron magnet is 1.96 m × 1.30 m × 1.21 m; its weight is 17.3 ton; its coil current is 88,024 ampere-turn; its center magnetic field is 1.27479 T; its maximum magnetic field is 1.942116 T; its minimum magnetic field is 0.7689 T; its valley gap is 120 mm; its hill gaps are 40 to 50.78 mm; and its hill angles are 35° to 44°.to 44°

  7. Molybdenum disulfide nanoflower-chitosan-Au nanoparticles composites based electrochemical sensing platform for bisphenol A determination

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ke-Jing, E-mail: kejinghuang@163.com [College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Liu, Yu-Jie; Liu, Yan-Ming; Wang, Ling-Ling [College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000 (China)

    2014-07-15

    Highlights: • This work constructs a novel electrochemical biosensor for bisphenol A detection. • Flower-like MoS{sub 2} are prepared by a simple hydrothermal procedure. • AuNPs are assembled on MoS{sub 2} nanoflowers modified electrode for signal amplification. • The developed sensor exhibits low detection limit and wide linear range. - Abstract: Two-dimensional transition metal dichalcogenide are attracting increasing attention in electrochemical sensing due to their unique electronic properties. In this work, flower-like molybdenum disulfide (MoS{sub 2}) was prepared by a simple hydrothermal method. The scanning electron microscopy and transmission electron microscopy images showed the MoS{sub 2} nanoflower had sizes with diameter of about 200 nm and was constructed with many irregular sheets as a petal-like structure with thickness of several nanometers. A novel electrochemical sensor was constructed for the determination of bisphenol A (BPA) based on MoS{sub 2} and chitosan-gold nanoparticles composites modified electrode. The sensor showed an efficient electrocatalytic role for the oxidation of BPA, and the oxidation overpotentials of BPA decreased significantly and the peak current increased greatly compared with bare GCE and other modified electrode. A good linear relationship between the oxidation peak current and BPA concentration was obtained in the range from 0.05 to 100 μM with a detection limit of 5.0 × 10{sup −9} M (S/N = 3). The developed sensor exhibited high sensitivity and long-term stability, and it was successfully applied for the determination of BPA in different samples. This work indicated MoS{sub 2} nanoflowers were promising in electrochemical sensing and catalytic applications.

  8. Cerimetric determination of simvastatin in pharmaceuticals based on redox and complex formation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Basavaiah, K.; Devi, O.Z [University of Mysore, Manasagangotri, Mysore (India). Dept. of Chemistry]. E-mail: basavaiahk@yahoo.co.in

    2008-07-01

    Two sensitive spectrophotometric methods are described for the determination of simvastatin (SMT) in bulk drug and in tablets. The methods are based on the oxidation of SMT by a measured excess of cerium (IV) in acid medium followed by determination of unreacted oxidant by two different reaction schemes. In one procedure (method A), the residual cerium (IV) is reacted with a fixed concentration of ferroin and the increase in absorbance is measured at 510 nm. The second approach (method B) involves the reduction of the unreacted cerium (IV) with a fixed quantity of iron (II), and the resulting iron (III) is complexed with thiocyanate and the absorbance measured at 470 nm. In both methods, the amount of cerium (IV) reacted corresponds to SMT concentration. The experimental conditions for both methods were optimized. In method A, the absorbance is found to increase linearly with SMT concentration (r = 0.9995) whereas in method B, the same decreased (r = -0.9943). The systems obey Beer's law for 0.6-7.5 and 0.5-5.0 {mu}g mL{sup -1} for method A and method B, respectively. The calculated molar absorptivity values are 2.7 X 104 and 1.06 X 105 Lmol{sup -1} cm{sup -1}, respectively; and the corresponding sandel sensitivity values are 0.0153 and 0.0039 {mu}g cm{sup -2}, respectively. The limit of detection (LOD) and quantification (LOQ) are reported for both methods. Intra-day and inter-day precision, and accuracy of the methods were established as per the current ICH guidelines. The methods were successfully applied to the determination of SMT in tablets and the results were statistically compared with those of the reference method by applying the Student's t-test and F-test. No interference was observed from the common excipients added to tablets. The accuracy and validity of the methods were further ascertained by performing recovery experiments via standard addition procedure. (author)

  9. The Determinants of Place of Death: An Evidence-Based Analysis

    Science.gov (United States)

    Costa, V

    2014-01-01

    Background According to a conceptual model described in this analysis, place of death is determined by an interplay of factors associated with the illness, the individual, and the environment. Objectives Our objective was to evaluate the determinants of place of death for adult patients who have been diagnosed with an advanced, life-limiting condition and are not expected to stabilize or improve. Data Sources A literature search was performed using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid Embase, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), and EBM Reviews, for studies published from January 1, 2004, to September 24, 2013. Review Methods Different places of death are considered in this analysis—home, nursing home, inpatient hospice, and inpatient palliative care unit, compared with hospital. We selected factors to evaluate from a list of possible predictors—i.e., determinants—of death. We extracted the adjusted odds ratios and 95% confidence intervals of each determinant, performed a meta-analysis if appropriate, and conducted a stratified analysis if substantial heterogeneity was observed. Results From a literature search yielding 5,899 citations, we included 2 systematic reviews and 29 observational studies. Factors that increased the likelihood of home death included multidisciplinary home palliative care, patient preference, having an informal caregiver, and the caregiver's ability to cope. Factors increasing the likelihood of a nursing home death included the availability of palliative care in the nursing home and the existence of advance directives. A cancer diagnosis and the involvement of home care services increased the likelihood of dying in an inpatient palliative care unit. A cancer diagnosis and a longer time between referral to palliative care and death increased the likelihood of inpatient hospice death. The quality of the evidence was considered low. Limitations Our results are based

  10. Determinants of high unmet need for presbyopia correction: a community-based study in northwest Ethiopia

    Directory of Open Access Journals (Sweden)

    Girum M

    2017-01-01

    Full Text Available Mikael Girum,1 Alemayehu Desalegn Gudeta,2 Destaye Shiferaw Alemu2 1Department of Ophthalmology and Optometry, College of Medicine and Health Science, Hawassa University, Awasa, 2Department of Optometry, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia Purpose: Lack of evidence on the magnitude of unmet presbyopia need, and barriers to uptake spectacles, limit appropriate planning and implementation of the provision of spectacles to address the backlog of uncorrected presbyopia. The purpose of this study was to determine the magnitude of unmet presbyopia need and the associated factors in Bahir Dar, Ethiopia.Materials and methods: A community-based cross-sectional study was conducted in 2015 in Bahir Dar. A multistage sampling technique was used to sample 729 study participants. Individuals more than 35 years of age who were unable to read the N8 line on a near vision chart unaided or with existing spectacles at 40 cm were considered as having unmet need for presbyopia correction. Distance and near visual acuities were measured by optometrists using Snellen illiterate E chart at 6 m and 40 m, respectively. Data were entered into Epi Info 2002 and analyzed using Statistical Package for Social Sciences version 16.0. Odds ratio (with 95% confidence interval [CI] was used to determine the strength of association. P-values <0.05 were considered statistically significant.Results: A total of 729 people were included in the study (response rate of 99.5%. The mean age ± standard deviation of participants was 48.9±8.8 years. Unmet presbyopic need was 69.2% (95% CI: 65.8%–72.6%. Age (36–45 years [adjusted odds ratio {AOR} = 3.95; 95% CI: 1.06, 4.80], having no eye checkup in the past 1 year (AOR = 8.36; 95% CI: 5.16, 13.7, lack of awareness about place of refraction service (AOR = 4.38; 95% CI: 1.36, 13.7, and female gender (AOR = 1.78; 95% CI: 1.68, 2.9 were determinants of unmet presbyopia need.Conclusion: The burden

  11. Determinants of follow-up participation in the Internet-based European influenza surveillance platform Influenzanet.

    Science.gov (United States)

    Bajardi, Paolo; Vespignani, Alessandro; Funk, Sebastian; Eames, Ken Td; Edmunds, W John; Turbelin, Clément; Debin, Marion; Colizza, Vittoria; Smallenburg, Ronald; Koppeschaar, Carl E; Franco, Ana O; Faustino, Vitor; Carnahan, Annasara; Rehn, Moa; Paolotti, Daniela

    2014-03-10

    "Influenzanet" is a network of Internet-based platforms aimed at collecting real-time data for influenza surveillance in several European countries. More than 30,000 European volunteers participate every year in the study, representing one of the largest existing Internet-based multicenter cohorts. Each week during the influenza season, participants are asked to report their symptoms (if any) along with a set of additional questions. Focusing on the first influenza season of 2011-12, when the Influenzanet system was completely harmonized within a common framework in Sweden, the United Kingdom, the Netherlands, Belgium, France, Italy, and Portugal, we investigated the propensity of users to regularly come back to the platform to provide information about their health status. Our purpose was to investigate demographic and behavioral factors associated with participation in follow-up. By means of a multilevel analysis, we evaluated the association between regular participation during the season and sociodemographic and behavioral characteristics as measured by a background questionnaire completed by participants on registration. We found that lower participation in follow-up was associated with lower educational status (odds ratio [OR] 0.80, 95% CI 0.75-0.85), smoking (OR 0.64, 95% CI 0.59-0.70), younger age (OR ranging from 0.30, 95% CI 0.26-0.33 to 0.70, 95% CI 0.64-0.77), not being vaccinated against seasonal influenza (OR 0.77, 95% CI 0.72-0.84), and living in a household with children (OR 0.69, 95% CI 0.65-0.74). Most of these results hold when single countries are analyzed separately. Given the opportunistic enrollment of sel