Science.gov

Sample records for preliminary neutronic evaluation

  1. A preliminary neutronic evaluation of high temperature engineering test reactor using the SCALE6 code

    NASA Astrophysics Data System (ADS)

    Tanure, L. P. A. R.; Sousa, R. V.; Costa, D. F.; Cardoso, F.; Veloso, M. A. F.; Pereira, C.

    2014-02-01

    Neutronic parameters of some fourth generation nuclear reactors have been investigated at the Departamento de Engenharia Nuclear/UFMG. Previous studies show the possibility to increase the transmutation capabilities of these fourth generation systems to achieve significant reduction concerning transuranic elements in spent fuel. To validate the studies, a benchmark on core physics analysis, related to initial testing of the High Temperature Engineering Test Reactor and provided by International Atomic Energy Agency (IAEA) was simulated using the Standardized Computer Analysis for Licensing Evaluation (SCALE). The CSAS6/KENO-VI control sequence and the 44-group ENDF/B-V 0 cross-section neutron library were used to evaluate the keff (effective multiplication factor) and the result presents good agreement with experimental value.

  2. Preliminary evaluation of neutron capture cross sections for /sup 144/Sm, /sup 145/Sm and /sup 145/Pm

    SciTech Connect

    Gardner, D.G.; Gardner, M.A.

    1986-02-13

    We have made preliminary neutron-capture cross-section calculations of the Hauser-Feshbach type for the isotopes /sup 144/Sm, /sup 145/Sm, and /sup 145/Pm to investigate the production of radioactive /sup 145/Pm by neutron capture on the stable isotope /sup 144/Sm. The calculations were made for incident neutron energies from 2.5 MeV to about 1/sup -4/ or 10/sup -5/ MeV, wherever the first unbound resonance was estimated to occur in each case. At that energy, the calculated value was reduced by a somewhat arbitrary factor, and the excitation function extended down to thermal energy using a (E/sub n/)/sup -1/2/ energy dependence. Since very large uncertainties are associated with the position and magnitude of the first unbound resonance and the subsequent extrapolation back to thermal energy, the cross sections in this low-energy region should not be considered more accurate than +- a factor of 10. For incident neutron energies above each step, the calculations represent an average through the separated and overlapping resonance regions and may be accurate to better than +- a factor of 2. 18 refs., 7 figs., 5 tabs.

  3. A preliminary neutron crystallographic study of thaumatin

    SciTech Connect

    Teixeira, Susana C. M.; Blakeley, Matthew P.; Leal, Ricardo M. F.; Mitchell, Edward P.; Forsyth, V. Trevor

    2008-05-01

    Preliminary neutron crystallographic data from the sweet protein thaumatin have been recorded using the LADI-III diffractometer at the Institut Laue Langevin (ILL). The results illustrate the feasibility of a full neutron structural analysis aimed at further understanding the molecular basis of the perception of sweet taste. Such an analysis will exploit the use of perdeuterated thaumatin. A preliminary neutron crystallographic study of the sweet protein thaumatin is presented. Large hydrogenated crystals were prepared in deuterated crystallization buffer using the gel-acupuncture method. Data were collected to a resolution of 2 Å on the LADI-III diffractometer at the Institut Laue Langevin (ILL). The results demonstrate the feasibility of a full neutron crystallographic analysis of this structure aimed at providing relevant information on the location of H atoms, the distribution of charge on the protein surface and localized water in the structure. This information will be of interest for understanding the specificity of thaumatin–receptor interactions and will contribute to further understanding of the molecular mechanisms underlying the perception of taste.

  4. Preliminary Evaluation of Cavitation-Erosion Resistance of Ti-Alloys in Mercury for the Spallation Neutron Source

    SciTech Connect

    Pawel, Steven J; Mansur, Louis K

    2010-01-01

    A number of Ti-based alloys in both the mill-annealed and 20% cold-worked conditions were subjected to sonication conditions in Hg using a vibratory horn to assess relative cavitation-erosion resistance. Weight loss as a function of exposure time was roughly proportional to hardness for all alloys/conditions examined, with Ti-6Al-4V (Ti-Grade 5) and Ti-6Al-2Sn-4Zr-2Mo yielding the best resistance to cavitation-erosion as evidenced by low weight losses and little or no tendency to form pits on the exposed surface. Unalloyed Ti (Ti-Grade 4) and Ti-0.12Pd (Ti-Grade 7) exhibited greater weight losses by a factor or about two and about five, respectively, with Ti-0.12Pd particularly prone to pitting development. The mean erosion rates of the best two Ti-alloys examined here were about a factor of three higher than identically tested 316LN stainless steel following a low temperature carburizing treatment, but this difference is considered minor given that the rate for both materials is very low/manageable and represents a through-thickness property for the Ti-alloys. A nitriding surface treatment was also evaluated as a potential method to further increase the cavitation-erosion resistance of these alloys in Hg, but the selected treatment proved largely ineffective. Recommendations for further work to evaluate the efficacy of Ti-based alloys for use in high-powered targets for the Spallation Neutron Source are given.

  5. Preliminary Analysis of the Multisphere Neutron Spectrometer

    NASA Technical Reports Server (NTRS)

    Goldhagen, P.; Kniss, T.; Wilson, J. W.; Singleterry, R. C.; Jones, I. W.; VanSteveninck, W.

    2003-01-01

    Crews working on present-day jet aircraft are a large occupationally exposed group with a relatively high average effective dose from galactic cosmic radiation. Crews of future high-speed commercial aircraft flying at higher altitudes would be even more exposed. To help reduce the significant uncertainties in calculations of such exposures, the Atmospheric Ionizing Radiation (AIR) Project, an international collaboration of 15 laboratories, made simultaneous radiation measurements with 14 instruments on five flights of a NASA ER-2 high-altitude aircraft. The primary AIR instrument was a highly sensitive extended-energy multisphere neutron spectrometer with lead and steel shells placed within the moderators of two of its 14 detectors to enhance response at high energies. Detector responses were calculated for neutrons and charged hadrons at energies up to 100 GeV using MCNPX. Neutron spectra were unfolded from the measured count rates using the new MAXED code. We have measured the cosmic-ray neutron spectrum (thermal to greater than 10 GeV), total neutron fluence rate, and neutron effective dose and dose equivalent rates and their dependence on altitude and geomagnetic cutoff. The measured cosmic-ray neutron spectra have almost no thermal neutrons, a large "evaporation" peak near 1 MeV and a second broad peak near 100 MeV which contributes about 69% of the neutron effective dose. At high altitude, geomagnetic latitude has very little effect on the shape of the spectrum, but it is the dominant variable affecting neutron fluence rate, which was 8 times higher at the northernmost measurement location than it was at the southernmost. The shape of the spectrum varied only slightly with altitude from 21 km down to 12 km (56 - 201 grams per square centimeter atmospheric depth), but was significantly different on the ground. In all cases, ambient dose equivalent was greater than effective dose for cosmic-ray neutrons.

  6. Geohydrologic data collected from shallow neutron-access boreholes and resultant-preliminary geohydrologic evaluations, Yucca Mountain area, Nye County, Nevada

    SciTech Connect

    Blout, D.O.; Hammermeister, D.P.; Loskot, C.L.; Chornack, M.P.

    1994-12-31

    In cooperation with the US Department of Energy, 74 neutron-access boreholes were drilled in and near the southwestern part of the Nevada Test Site, Nye County, Nevada. Drilling, coring, sample collection and handling, and lithologic and preliminary geohydrologic data are presented in this report. The boreholes were drilled in a combination of alluvium/colluvium, ash-flow tuff, ash-fall tuff, or bedded tuff to depths of 4.6 to 36.6 meters. Air was used as a drilling medium to minimize disturbance of the water content and water potential of drill cuttings, core, and formation rock. Drill cuttings were collected at approximately 0.6-meter intervals. Core was taken at selected intervals from the alluvium/colluvium using drive-coring methods and from tuff using rotary-coring methods. Nonwelded and bedded tuffs were continuously cored using rotary-coring methods. Gravimetric water-content and water-potential values of core generally were greater than those of corresponding drill cuttings. Gravimetric water-content, porosity, and water-potential values of samples generally decreased, and bulk density values increased, as the degree of welding increased. Grain-density values remained fairly constant with changes in the degree of welding. A high degree of spatial variability in water-content and water-potential profiles was noted in closely spaced boreholes that penetrate similar lithologic subunits and was also noted in adjacent boreholes located in different topographic positions. Variability within a thick lithologic unit usually was small. 18 refs., 21 figs., 17 tabs.

  7. Preliminary calibration of the ACP safeguards neutron counter

    NASA Astrophysics Data System (ADS)

    Lee, T. H.; Kim, H. D.; Yoon, J. S.; Lee, S. Y.; Swinhoe, M.; Menlove, H. O.

    2007-10-01

    The Advanced Spent Fuel Conditioning Process (ACP), a kind of pyroprocess, has been developed at the Korea Atomic Energy Research Institute (KAERI). Since there is no IAEA safeguards criteria for this process, KAERI has developed a neutron coincidence counter to make it possible to perform a material control and accounting (MC&A) for its ACP materials for the purpose of a transparency in the peaceful uses of nuclear materials at KAERI. The test results of the ACP Safeguards Neutron Counter (ASNC) show a satisfactory performance for the Doubles count measurement with a low measurement error for its cylindrical sample cavity. The neutron detection efficiency is about 21% with an error of ±1.32% along the axial direction of the cavity. Using two 252Cf neutron sources, we obtained various parameters for the Singles and Doubles rates for the ASNC. The Singles, Doubles, and Triples rates for a 252Cf point source were obtained by using the MCNPX code and the results for the ft8 cap multiplicity tally option with the values of ɛ, fd, and ft measured with a strong source most closely match the measurement results to within a 1% error. A preliminary calibration curve for the ASNC was generated by using the point model equation relationship between 244Cm and 252Cf and the calibration coefficient for the non-multiplying sample is 2.78×10 5 (Doubles counts/s/g 244Cm). The preliminary calibration curves for the ACP samples were also obtained by using an MCNPX simulation. A neutron multiplication influence on an increase of the Doubles rate for a metal ingot and UO2 powder is clearly observed. These calibration curves will be modified and complemented, when hot calibration samples become available. To verify the validity of this calibration curve, a measurement of spent fuel standards for a known 244Cm mass will be performed in the near future.

  8. Preliminary On-Orbit Neutron Dose Equivalent and Energy Spectrum Results from the ISS-RAD Fast Neutron Detector (FND)

    NASA Technical Reports Server (NTRS)

    Semones, Edward; Leitgab, Martin

    2016-01-01

    The ISS-RAD instrument was activated on ISS on February 1st, 2016. Integrated in ISS-RAD, the Fast Neutron Detector (FND) performs, for the first time on ISS, routine and precise direct neutron measurements between 0.5 and 8 MeV. Preliminary results for neutron dose equivalent and neutron flux energy distributions from online/on-board algorithms and offline ground analyses will be shown, along with comparisons to simulated data and previously measured neutron spectral data. On-orbit data quality and pre-launch analysis validation results will be discussed as well.

  9. Evaluation of a Polyvinyl Toluene Neutron Counter Array

    SciTech Connect

    Robert Hayes

    2008-03-01

    The purpose of this article is to simulate the performance of a neutron detector array for empirical configuration optimization and preliminary algorithm evaluation. Utilizing a compact array of borated Polyvinyl Toluene light pipes and Photomultiplier Tubes, pulse shape analysis, standard spectral histogramming, and multiplicity counting can enable neutron measurements for multiple applications. Results demonstrate that analysis with Monte Carlo N-Particle (MCNP) can be used to obtain a better understanding of field measurement results and aid in algorithm development for unfolding in conjunction with detector optimization. Use of a handheld neutron spectrometer has promise of widespread applicability. By correlating MCNP results with empirical measurements, substantial confidence can be placed on predicting detector response to sufficiently similar spectral sources under alternate experimental configurations. In addition, use of the detector has substantial promise for operational health physics applications.

  10. Covariance Evaluation Methodology for Neutron Cross Sections

    SciTech Connect

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.

    2008-09-01

    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  11. Preliminary investigations of Monte Carlo Simulations of neutron energy and LET spectra for fast neutron therapy facilities

    SciTech Connect

    Kroc, T.K.; /Fermilab

    2009-10-01

    No fast neutron therapy facility has been built with optimized beam quality based on a thorough understanding of the neutron spectrum and its resulting biological effectiveness. A study has been initiated to provide the information necessary for such an optimization. Monte Carlo studies will be used to simulate neutron energy spectra and LET spectra. These studies will be bench-marked with data taken at existing fast neutron therapy facilities. Results will also be compared with radiobiological studies to further support beam quality ptimization. These simulations, anchored by this data, will then be used to determine what parameters might be optimized to take full advantage of the unique LET properties of fast neutron beams. This paper will present preliminary work in generating energy and LET spectra for the Fermilab fast neutron therapy facility.

  12. Preliminary Criticality Safety Evaluation for In Situ Grouting in the Subsurface Disposal Area

    SciTech Connect

    Slate, Lawrence J; Taylor, Joseph Todd

    2000-08-01

    A preliminary criticality safety evaluation is presented for in situ grouting in the Subsurface Disposal Area (SDA) at the Idaho National Engineering Laboratory. The grouting materials evaluated are cement and paraffin. The evaluation determines physical and administrative controls necessary to preclude criticality and identifies additional information required for a final criticality safety evaluation. The evaluation shows that there are no criticality concerns with cementitious grout but a neutron poison such as boron would be required for the use of the paraffin matrix.

  13. Preliminary Criticality Safety Evaluation for In Situ Grouting in the Subsurface Disposal Area

    SciTech Connect

    Slate, L.J.; Taylor, J.T.

    2000-08-31

    A preliminary criticality safety evaluation is presented for in situ grouting in the Subsurface Disposal Area (SDA) at the Idaho National Engineering Laboratory. The grouting materials evaluated are cement and paraffin. The evaluation determines physical and administrative controls necessary to preclude criticality and identifies additional information required for a final criticality safety evaluation. The evaluation shows that there are no criticality concerns with cementitious grout but a neutron poison such as boron would be required for the use of the paraffin matrix.

  14. Preliminary results on bubble detector as personal neutron dosemeter.

    PubMed

    Ponraju, D; Krishnan, H; Viswanathan, S; Indira, R

    2011-03-01

    The bubble detector is demonstrated as one of the best suitable neutron detectors for neutron dose rate measurements in the presence of high-intense gamma fields. Immobilisation of a volatile liquid in a superheated state and achieving uniform distribution of tiny superheated droplets were a practical challenge. A compact and reusable bubble detector with high neutron sensitivity has been developed at the Indira Gandhi Centre for Atomic Research by immobilising the superheated droplets in a suitable polymer matrix. Two types of bubble detectors have been successfully developed, one by incorporating isobutane for measuring fast neutron and another by incorporating Freon-12 for both fast and thermal neutron. The performance of the detector has been tested using 5 Ci Am-Be neutron source and the results are described. PMID:21217133

  15. Preliminary study of MAGAT polymer gel dosimetry for boron-neutron capture therapy

    NASA Astrophysics Data System (ADS)

    Hayashi, Shin-ichiro; Sakurai, Yoshinori; Uchida, Ryohei; Suzuki, Minoru; Usui, Shuji; Tominaga, Takahiro

    2015-01-01

    MAGAT gel dosimeter with boron is irradiated in Heavy Water Neutron Irradiation Facility (HWNIF) of Kyoto University Research Reactor (KUR). The cylindrical gel phantoms are exposed to neutron beams of three different energy spectra (thermal neutron rich, epithermal and fast neutron rich and the mixed modes) in air. Preliminary results corresponding to depth-dose responses are obtained as the transverse relaxation rate (R2=1/T2) from magnetic resonance imaging data. As the results MAGAT gel dosimeter has the higher sensitivity on thermal neutron than on epi-thermal and fast neutron, and the gel with boron showed an enhancement and a change in the depth-R2 response explicitly. From these results, it is suggested that MAGAT gel dosimeter can be an effective tool in BNCT dosimetry.

  16. Preliminary studies on neutron conversion coefficients calculated with MCNPX in NORMAN voxel phantom.

    PubMed

    Gualdrini, G; Ferrari, P

    2007-01-01

    Effective dose is the main radiation protection quantity. Progresses in radiation studies brought ICRP to revise ICRP 60 recommendations. A new publication, already circulated in form of draft, is expected to change some aspects of effective dose evaluation method. The organ absorbed doses for neutrons at various energies and incidence angles, necessary to estimate the effective dose, have been published in ICRU 57 and ICRP 74 reports for ADAM and EVA analytical male and female phantoms and similar calculations were also performed, based on the MCNP code, for VIP-MAN voxel phantom. The NORMAN voxel phantom, developed on the basis of magnetic resonance data of an adult male at HPA (formerly NRPB), is an accurate model (with a voxel element of approximately 8 mm(3)), which well approximates the standard man and has been already employed for radiation protection studies with photons. In the present paper, a modified version, called NORMAN-05, including a new organ, the salivary glands (as suggested in the mentioned ICRP draft), and a more detailed skeletal description, especially devoted to red bone marrow dose evaluation, has been employed with the Monte Carlo code MCNPX to calculate neutron conversion coefficients from thermal energies to 20 MeV. Some preliminary results, for antero-posterior and postero-anterior irradiation conditions, are presented and compared with the available published data. PMID:17502319

  17. International Evaluation of Neutron Cross Section Standards

    NASA Astrophysics Data System (ADS)

    Carlson, A. D.; Pronyaev, V. G.; Smith, D. L.; Larson, N. M.; Chen, Zhenpeng; Hale, G. M.; Hambsch, F.-J.; Gai, E. V.; Oh, Soo-Youl; Badikov, S. A.; Kawano, T.; Hofmann, H. M.; Vonach, H.; Tagesen, S.

    2009-12-01

    Neutron cross section standards are the basis for the determination of most neutron cross sections. They are used for both measurements and evaluations of neutron cross sections. Not many cross sections can be obtained absolutely - most cross sections are measured relative to the cross section standards and converted using evaluations of the standards. The previous complete evaluation of the neutron cross section standards was finished in 1987 and disseminated as the NEANDC/INDC and ENDF/B-VI standards. R-matrix model fits for the light elements and non-model least-squares fits for all the cross sections in the evaluation were the basis of the combined fits for all of the data. Some important reactions and constants are not standards, but they assist greatly in the determination of the standard cross sections and reduce their uncertainties - these data were also included in the combined fits. The largest experimental database used in the evaluation was prepared by Poenitz and included about 400 sets of experimental data with covariance matrices of uncertainties that account for all cross-energy, cross-reaction and cross-material correlations. For the evaluation GMA, a least-squares code developed by Poenitz, was used to fit all types of cross sections (absolute and shape), their ratios, spectrum-averaged cross sections and thermal constants in one full analysis. But, the uncertainties derived in this manner, and especially those obtained in the R-matrix model fits, have been judged to be too low and unrealistic. These uncertainties were substantially increased prior to their release in the recommended data files of 1987. Modified percentage uncertainties were reassigned by the United States Cross Section Evaluation Working Group's Standards Subcommittee for a wide range of energies, and no covariance (or correlation) matrices were supplied at that time. The need to re-evaluate the cross section standards is based on the appearance of a significant amount of precise

  18. Preliminary detector design ST862-prototype neutron detector

    SciTech Connect

    Miller, S.D.; Affinito, J.D.; Sisk, D.R.

    1993-12-01

    The detection of fast neutrons has been accomplished with commercially available liquid scintillators in detectors. Liquid scintillators discriminate fast neutrons from gamma radiation by discarding pulses with short decay constants. However, pulse-timing methods require expensive, bulky equipment and a high degree of technical sophistication in the user. Researchers at Pacific Northwest Laboratory have developed a new class of scintillating material, polymerizing crystals of CaF{sub 2}(Eu) and liquid acrylate monomers with matched indexes of refraction. The new detectors avoid the pulse-timing methods of liquid detectors and allow detectors to be large and relatively light. Fast neutrons can be discriminated from gamma radiation solely on the basis of pulse height (i.e., energy deposition). Using these detectors, a hand-held neutron detection instrument is proposed that can operate on battery power for 8 to 12 hours and be easily used in field conditions for surveying vehicles and structures.

  19. Preliminary Pulsing Experiments to Measure Delayed Neutron Emission Parameters

    SciTech Connect

    Charlton, W.S.; Parish, T.A.; Raman, S.

    1998-10-05

    Recent interest in delayed neutron parameters including comparisons between macroscopic (experimental) and microscopic (calculated) results have prompted a set of experiments using the 1MW Triga Reactor at the Texas A and M University (TAMU) Nuclear Science Center (NSC) designed to measure the complete set of seven-group delayed neutron parameters for several higher actinides. Operating the Nuclear Science Center Reactor (NSCR) in a pulsed mode, a complete set of delayed neutron parameters were measured for Np-237 and Am-243. The total delayed neutron yield per 100 fissions for Np-237 and Am-243 was found to be 1.14 {+-} 0.07 and 0.85 {+-} 0.05, respectively. Comparisons to previous measurements are made where such measurements are available.

  20. Preliminary neutron crystallographic analysis of selectively CH3-protonated, deuterated rubredoxin from Pyrococcus furiosus

    SciTech Connect

    Weiss, Kevin L; Meilleur, Flora; Blakeley, Matthew; Myles, Dean A A

    2008-01-01

    Neutron crystallography is used to locate hydrogen atoms in biological materials and can distinguish between negatively scattering hydrogen and positively scattering deuterium substituted positions in isomorphous neutron structures. Recently, Hauptman and Langs (2003) have shown that neutron diffraction data can be used to solve macromolecular structures by direct methods and that solution is aided by the presence of negatively scattering hydrogen atoms in the structure. Selective labeling protocols allow the design and production of H/D-labeled macromolecular structures in which the ratio of hydrogen to deuterium atoms can be precisely controlled. We have applied methyl-selective labeling protocols to introduce (1H-delta methyl)-leucine and (1H-gamma methyl)-valine into deuterated rubredoxin from Pyrococcus furiosus (PfRd). Here we report on the production, crystallization, and preliminary neutron analysis of the selectively CH3-protonated, deuterated PfRd sample, which provided a high quality neutron data set extending to 1.75 resolution at the new LADI-III instrument at the Insititut Laue-Langevin. Preliminary analysis of neutron density maps allows unambiguous assignment of the positions of hydrogen atoms at the methyl groups of the valine and leucine residues in the otherwise deuterated rubredoxin structure.

  1. A preliminary neutron diffraction analysis of Achromobacter protease I

    NASA Astrophysics Data System (ADS)

    Ohnishi, Yuki; Masaki, Takeharu; Yamada, Taro; Kurihara, Kazuo; Tanaka, Ichiro; Niimura, Nobuo

    2010-11-01

    Achromobacter protease I (API, E.C. 3.4.21.50) is one of the serine proteases produced by Achromobacter lyticus M497-1. API is distinct from the other tripsin type protease in its lysine specificity. The neutron structure analysis of catalytic triad with Trp169 and His210 was presented. His57 was double protonated and formed hydrogen bonds to Ser194Oγ and Asp113Oδ1, Oδ2.

  2. Sandia solar dryer: preliminary performance evaluation

    SciTech Connect

    Glass, J.S.; Holm-Hansen, T.; Tills, J.; Pierce, J.D.

    1986-01-01

    Preliminary performance evaluations were conducted with the prototype modular solar dryer for wastewater sludge at Sandia National Laboratories. Operational parameters which appeared to influence sludge drying efficiency included condensation system capacity and air turbulence at the sludge surface. Sludge heating profiles showed dependencies on sludge moisture content, sludge depth and seasonal variability in available solar energy. Heat-pasteurization of sludge in the module was demonstrated in two dynamic-processing experiments. Through balanced utilization of drying and heating functions, the facility has the potential for year-round sludge treatment application.

  3. Preliminary analysis of the distribution of water in human hair by small-angle neutron scattering.

    PubMed

    Kamath, Yash; Murthy, N Sanjeeva; Ramaprasad, Ram

    2014-01-01

    Diffusion and distribution of water in hair can reveal the internal structure of hair that determines the penetration of various products used to treat hair. The distribution of water into different morphological components in unmodified hair, cuticle-free hair, and hair saturated with oil at various levels of humidity was examined using small-angle neutron scattering (SANS) by substituting water with deuterium oxide (D(2)O). Infrared spectroscopy was used to follow hydrogen-deuterium exchange. Water present in hair gives basically two types of responses in SANS: (i) interference patterns, and (ii) central diffuse scattering (CDS) around the beam stop. The amount of water in the matrix between the intermediate filaments that gives rise to interference patterns remained essentially constant over the 50-98% humidity range without swelling this region of the fiber extensively. This observation suggests that a significant fraction of water in the hair, which contributes to the CDS, is likely located in a different morphological region of hair that is more like pores in a fibrous structure, which leads to significant additional swelling of the fiber. Comparison of the scattering of hair treated with oil shows that soybean oil, which diffuses less into hair, allows more water into hair than coconut oil. These preliminary results illustrate the utility of SANS for evaluating and understanding the diffusion of deuterated liquids into different morphological structures in hair.

  4. Preliminary neutron and X-ray crystallographic studies of equine cyanomethemoglobin

    SciTech Connect

    Kovalevsky, A.Y.; Fisher, S.Z.; Seaver, S.; Mustyakimov, M.; Sukumar, N.; Langan, P.; Mueser, T.C.; Hanson, B.L.

    2010-08-18

    Room-temperature and 100 K X-ray and room-temperature neutron diffraction data have been measured from equine cyanomethemoglobin to 1.7 {angstrom} resolution using a home source, to 1.6 {angstrom} resolution on NE-CAT at the Advanced Photon Source and to 2.0 {angstrom} resolution on the PCS at Los Alamos Neutron Science Center, respectively. The cyanomethemoglobin is in the R state and preliminary room-temperature electron and neutron scattering density maps clearly show the protonation states of potential Bohr groups. Interestingly, a water molecule that is in the vicinity of the heme group and coordinated to the distal histidine appears to be expelled from this site in the low-temperature structure.

  5. Evaluation of neutron radiation field in carbon ion therapy

    NASA Astrophysics Data System (ADS)

    Xu, Jun-Kui; Su, You-Wu; Li, Wu-Yuan; Yan, Wei-Wei; Chen, Xi-Meng; Mao, Wang; Pang, Cheng-Guo

    2016-01-01

    Carbon ions have significant advantages in tumor therapy because of their physical and biological properties. In view of the radiation protection, the safety of patients is the most important issue in therapy processes. Therefore, the effects of the secondary particles produced by the carbon ions in the tumor therapy should be carefully considered, especially for the neutrons. In the present work, the neutron radiation field induced by carbon ions was evaluated by using the FLUKA code. The simulated results of neutron energy spectra and neutron dose was found to be in good agreement with the experiment data. In addition, energy deposition of carbon ions and neutrons in tissue-like media was studied, it is found that the secondary neutron energy deposition is not expected to exceed 1% of the carbon ion energy deposition in a typical treatment.

  6. Preliminary evaluation of an automated metaphase finder

    SciTech Connect

    McFee, A.F.; Littlefield, L.G.

    1994-12-31

    Computer driven microscope units are available for the automated analysis of cytogenetic preparations. Their greatest benefit is the speed with which they can scan slides, locate metaphases, and display them for operator evaluation. We have preliminary evaluated the AKS-500 automated metaphase finding system (Imagenetics, Inc., Framingham, MA) to determine if it significantly improves the speed and/or efficiency with which metaphase figures can be located and evaluated. This unit accepts 8 microscope slides on a motorized stage and, following a 15-20 minute loading process, proceeds unattended to systematically scan all or a set portion of the slides, identifies metaphase figures, and stores their coordinate locations in memory. On command, metaphases are recalled and presented in the microscope field or evaluation, either in the search order in which they were encountered, or after a quality sort by the computer. Aberrations were scored in bone marrow metaphases from DMBA-treated mice which had been located by the machine, and compared to manual scoring of the same slides. Aberration rates did not differ when metaphases were scored in search order, but quality evaluation by the computer discriminated against heavily damaged metaphases. The time required to score 50 metaphases/slide was {approximately}30 min, compared with {approximately}3 hr for manual scoring of the same slides. On slides from human lymphocyte cultures, the machine located only about half as many metaphases as were identified in systematic manual searches of the slides, but the samples contained a higher proportion of scorable quality metaphases. A procedure has also been developed whereby Giesma-stained metaphases can be located, destained, and rapidly relocated after chromosome painting by FISH techniques.

  7. Evaluated Neutron Nuclear Data for Reactor Physics Calculations.

    1988-09-15

    Version 00 The data file KEDAK contains the evaluated neutron nuclear data for a number of materials important for the reactor physics, specific physical experiments, burn up calculations, shielding and other applications.

  8. Introducing Nuclear Data Evaluations of Prompt Fission Neutron Spectra

    SciTech Connect

    Neudecker, Denise

    2015-06-17

    Nuclear data evaluations provide recommended data sets for nuclear data applications such as reactor physics, stockpile stewardship or nuclear medicine. The evaluated data are often based on information from multiple experimental data sets and nuclear theory using statistical methods. Therefore, they are collaborative efforts of evaluators, theoreticians, experimentalists, benchmark experts, statisticians and application area scientists. In this talk, an introductions is given to the field of nuclear data evaluation at the specific example of a recent evaluation of the outgoing neutron energy spectrum emitted promptly after fission from 239Pu and induced by neutrons from thermal to 30 MeV.

  9. Preliminary neutronic studies for the liquid-salt-cooled very hightemperature reactor (LS-VHTR).

    SciTech Connect

    Kim, T. K.; Taiwo, T. A.; Yang, W. S.

    2005-10-05

    Preliminary neutronic studies have been performed in order to provide guidelines to the design of a liquid-salt cooled Very High Temperature Reactor (LS-VHTR) using Li{sub 2}BeF{sub 4} (FLiBe) as coolant and a solid cylindrical core. The studies were done using the lattice codes (WIMS8 and DRAGON) and the linear reactivity model to estimate the core reactivity balance, fuel composition, discharge burnup, and reactivity coefficients. An evaluation of the lattice codes revealed that they give very similar accuracy as the Monte Carlo MCNP4C code for the prediction of the fuel element multiplication factor (kinf) and the double heterogeneity effect of the coated fuel particles in the graphite matrix. The loss of coolant from the LS-VHTR core following coolant voiding was found to result in a positive reactivity addition, due primarily to the removal of the strong neutron absorber Li-6. To mitigate this positive reactivity addition and its impact on reactor design (positive void reactivity coefficient), the lithium in the coolant must be enriched to greater than 99.995% in its Li-7 content. For the reference LS-VHTR considered in this work, it was found that the magnitude of the coolant void reactivity coefficient (CVRC) is quite small (less than $1 for 100% voiding). The coefficient was found to become more negative or less positive with increase in the lithium enrichment (Li-7 content). It was also observed that the coefficient is positive at the beginning of cycle and becomes more negative with increasing burnup, indicating that by using more than one fuel batch, the coefficient could be made negative at the beginning of cycle. It might, however, still be necessary at the beginning of life to design for a negative CVRC value. The study shows that this can be done by using burnable poisons (erbium is a leading candidate) or by changing the reference assembly design (channel dimensions) in order to modify the neutron spectrum. Parametric studies have been performed to

  10. Preliminary Evaluation of a New Cosmology Curriculum

    NASA Astrophysics Data System (ADS)

    Coble, Kimberly A.; Martin, Dominique; Hayes, Patrycia; Targett, Tom; Bailey, Janelle M.; Cominsky, Lynn R.

    2015-01-01

    Informed by our research on student understanding of cosmology, The Big Ideas in Cosmology is an immersive set of web-based learning modules that integrates text, figures, and visualizations with short and long interactive tasks and real cosmological data. This enables the transformation of general education astronomy and cosmology classes from primarily lecture and book-based courses to a more engaging format that builds important STEM skills.During the spring 2014 semester, we field-tested a subset of chapters with the general education astronomy and cosmology classes at Sonoma State University in a flipped-classroom format. We administered pre and post content and attitude assessments in the two flipped classes as well as two lecture classes. The majority of cosmology students had taken astronomy before whereas the astronomy students had not.When switching to an active mode of learning (e.g., flipped classroom instead of lecture), many instructors report pushback from students. We saw this effect from students in course evaluations, who reported dissatisfaction with "having to do more work." However, the students in the flipped section in astronomy made greater gains on the multiple choice content assessment than the students in either of the two lecture sections. On the attitude assessment (the CLASS), the cosmology students made a small shift toward more expert-like opinions. Preliminary results from open-ended content surveys indicate that, prior to instruction, students had difficulty answering 'why' or 'how do we know' questions; that post-instruction, students are less likely to respond "I don't know" or to leave an answer blank; and that students using the modules made gains in their content knowledge.Module development was supported by NASA ROSES E/PO Grant #NNXl0AC89G, the Illinois Space Grant Consortium, the Fermi E/PO program, Sonoma State University's Space Science Education and Public Outreach Group, and Great River Technology

  11. An evaluated neutronic data file for elemental cobalt

    SciTech Connect

    Guenther, P.; Lawson, R.; Meadows, J.; Sugimoto, M.; Smith, A.; Smith, D.; Howerton, R.

    1988-08-01

    A comprehensive evaluated neutronic data file for elemental cobalt is described. The experimental data base, the calculational methods, the evaluation techniques and judgments, and the physical content are outlined. The file contains: neutron total and scattering cross sections and associated properties, (n,2n) and (n,3n) processes, neutron radiative capture processes, charged-particle-emission processes, and photon-production processes. The file extends from 10/sup /minus/5/ eV to 20 MeV, and is presented in the ENDF/B-VI format. Detailed attention is given to the uncertainties and correlations associated with the prominent neutron-induced processes. The numerical contents of the file have been transmitted to the National Nuclear Data Center, Brookhaven National Laboratory. 143 refs., 16 figs., 5 tabs.

  12. EPICS V4 Evaluation for SNS Neutron Data

    SciTech Connect

    Kasemir, Kay; Pearson, Matthew R; Guyotte, Greg S

    2015-01-01

    Version 4 of the Experimental Physics and Industrial Control System (EPICS) toolkit allows defining application-specific structured data types (pvData) and offers a network protocol for their efficient exchange (pvAccess). We evaluated V4 for the transport of neutron events from the detectors of the Spallation Neutron Source (SNS) to data acquisition and experiment monitoring systems. This includes the comparison of possible data structures, performance tests, and experience using V4 in production on a beam line.

  13. Evaluation of Tungsten Neutron Cross Sections in the Resolved Resonance Region

    NASA Astrophysics Data System (ADS)

    Pigni, M. T.; Leal, L. C.; Dunn, M. E.; Guber, K. H.; Trkov, A.; Žerovnik, G.; Emiliani, F.; Kopecky, S.; Lampoudis, C.; Schillebeeckx, P.; Siegler, P.

    2014-04-01

    We generated a preliminary set of resonance parameters for 182,183,184,186W in the neutron energy range of thermal up to several keV. The evaluation methodology uses the Reich-Moore approximation to fit with the R-matrix code SAMMY, the high-resolution measurements performed in 2010 and 2012 at the Geel linear accelerator facility. For 183W, the transmission data and capture cross sections calculated with the set of resonance parameters are compared with the experimental values, and some of the average properties of the resonance parameters are discussed. In the analyzed energy range, this work almost doubles the existing resolved resonance evaluations in the ENDF/B-VII.1 library. A preliminary analysis of the performance of the calculated cross sections based on Lead slowing-down benchmarks is presented and briefly discussed.

  14. Evaluation of the /sup 238/U neutron total cross section

    SciTech Connect

    Smith, A.; Poenitz, W.P.; Howerton, R.J.

    1982-12-01

    Experimental energy-averaged neutron total cross sections of /sup 238/U were evaluated from 0.044 to 20.0 MeV using regorous numerical methods. The evaluated results are presented together with the associated uncertainties and correlation matrix. They indicate that this energy-averaged neutron total cross section is known to better than 1% over wide energy regions. There are somwewhat larger uncertainties at low energies (e.g., less than or equal to 0.2 MeV), near 8 MeV and above 15 MeV. The present evaluation is compard with values given in ENDF/B-V.

  15. Preliminary evaluations of the undesirable patient dose from a BNCT treatment at the ENEA-TAPIRO reactor.

    PubMed

    Ferrari, P; Gualdrini, G; Nava, E; Burn, K W

    2007-01-01

    Boron neutron capture therapy (BNCT) is an experimental technique for the treatment of certain kinds of tumors. Research in BNCT is performed utilizing both thermal and epithermal neutron beams. Epithermal neutrons (0.4 eV-10 keV) penetrate more deeply into tissue and are thus used in non-superficial clinical applications such as the brain glioma. In the last few years, the fast reactor TAPIRO (ENEA-Casaccia Rome) has been employed as a neutron source for research into BNCT applications. Recently, an 'epithermal therapeutic column' has been designed and its construction has been completed. The Monte Carlo code MCNPX was employed to optimize the design of the column and to evaluate the dose profiles and the therapeutic parameters in the cranium of the anthropomorphic phantom ADAM. In the same context, some preliminary evaluations of the undesirable doses to the patient were performed with MCNPX. A hermaphrodite phantom derived from ADAM and EVA was employed to evaluate the energy deposition in some organs during a standard BNCT treatment. The total dose consists of the contributions from the primary neutron beam, the neutron interactions with boron and the neutron induced photons generated in the epithermal column structures and in the patient's tissues. The paper summarizes the computational procedure and provides a general dosimetric framework of the patient radiological protection aspects related to a BNCT treatment scenario at the TAPIRO reactor.

  16. Preliminary Neutronics Design Studies for a Molten Salt Blanket LIFE Engine

    SciTech Connect

    Powers, J

    2008-10-23

    The Laser Inertial Confinement Fusion Fission Energy (LIFE) Program being developed at Lawrence Livermore National Laboratory (LLNL) aims to design a hybrid fission-fusion subcritical nuclear engine that uses a laser-driven Inertial Confinement Fusion (ICF) system to drive a subcritical fission blanket. This combined fusion-fission hybrid system could be used for generating electricity, material transmutation or incineration, or other applications. LIFE does not require enriched fuel since it is a sub-critical system and LIFE can sustain power operation beyond the burnup levels at which typical fission reactors need to be refueled. In light of these factors, numerous options have been suggested and are being investigated. Options being investigated include fueling LIFE engines with spent nuclear fuel to aid in disposal/incineration of commercial spent nuclear fuel or using depleted uranium or thorium fueled options to enhance proliferation resistance and utilize non-fissile materials [1]. LIFE engine blanket designs using a molten salt fuel system represent one area of investigation. Possible applications of a LIFE engine with a molten salt blanket include uses as a spent nuclear fuel burner, fissile fuel breeding platform, and providing a backup alternative to other LIFE engine blanket designs using TRISO fuel particles in case the TRISO particles are found to be unable to withstand the irradiation they will be subjected to. These molten salts consist of a mixture of LiF with UF{sub 4} or ThF{sub 4} or some combination thereof. Future systems could look at using PuF{sub 3} or PuF{sub 4} as well, though no work on such system with initial plutonium loadings has been performed for studies documented in this report. The purpose of this report is to document preliminary neutronics design studies performed to support the development of a molten salt blanket LIFE engine option, as part of the LIFE Program being performed at Lawrence Livermore National laboratory

  17. Preliminary Neutronic Study of D2O-cooled High Conversion PWRs

    SciTech Connect

    Hikaru Hiruta; Gilles Youinou

    2013-10-01

    This paper presents a preliminary neutronics analysis of tight-pitch D2O-cooled high-conversion PWRs loaded with MOX fuel aiming at high Pu conversion and negative void coefficient. SCALE6.1 has been exclusively utilized for this study. The analyses are performed in two separate parts. The first part of this paper investigates the performance of axial and internal blankets and seeks break-even or near-breeder core even without the presence of radial blankets. The second part of this paper performs sensitivity and uncertainty analyses of integral parameters (keff and void coefficient) for selected systems in order to analyze the characters of this high-conversion PWR from different aspects.

  18. Preliminary economic evaluation of the Alkox process

    SciTech Connect

    Silva, L.J.; Lilga, M.A.; Camaioni, D.M.; Snowden, L.J.

    1991-09-01

    A new chemical process has been invented at Battelle Pacific Northwest Laboratories for converting alkanes to alcohols. This new chemistry has been named the Alkox Process.'' Pacific Northwest Laboratory prepared a preliminary economic analysis for converting cyclohexane to cyclohexanol, which may be one of the most attractive applications of the Alkox process. A process flow scheme and a material balance were prepared to support rough equipment sizing and costing. The results from the economic analysis are presented in the non-proprietary section of this report. The process details, including the flow diagram and material balance, are contained in separate section of this report that is proprietary to Battelle. 7 refs., 4 tabs.

  19. A Computerized Library and Evaluation System for Integral Neutron Experiments.

    ERIC Educational Resources Information Center

    Hampel, Viktor E.; And Others

    A computerized library of references to integral neutron experiments has been developed at the Lawrence Radiation Laboratory at Livermore. This library serves as a data base for the systematic retrieval of documents describing diverse critical and bulk nuclear experiments. The evaluation and reduction of the physical parameters of the experiments…

  20. MCNP5 and GEANT4 comparisons for preliminary Fast Neutron Pencil Beam design at the University of Utah TRIGA system

    NASA Astrophysics Data System (ADS)

    Adjei, Christian Amevi

    The main objective of this thesis is twofold. The starting objective was to develop a model for meaningful benchmarking of different versions of GEANT4 against an experimental set-up and MCNP5 pertaining to photon transport and interactions. The following objective was to develop a preliminary design of a Fast Neutron Pencil Beam (FNPB) Facility to be applicable for the University of Utah research reactor (UUTR) using MCNP5 and GEANT4. The three various GEANT4 code versions, GEANT4.9.4, GEANT4.9.3, and GEANT4.9.2, were compared to MCNP5 and the experimental measurements of gamma attenuation in air. The average gamma dose rate was measured in the laboratory experiment at various distances from a shielded cesium source using a Ludlum model 19 portable NaI detector. As it was expected, the gamma dose rate decreased with distance. All three GEANT4 code versions agreed well with both the experimental data and the MCNP5 simulation. Additionally, a simple GEANT4 and MCNP5 model was developed to compare the code agreements for neutron interactions in various materials. Preliminary FNPB design was developed using MCNP5; a semi-accurate model was developed using GEANT4 (because GEANT4 does not support the reactor physics modeling, the reactor was represented as a surface neutron source, thus a semi-accurate model). Based on the MCNP5 model, the fast neutron flux in a sample holder of the FNPB is obtained to be 6.52×107 n/cm2s, which is one order of magnitude lower than gigantic fast neutron pencil beam facilities existing elsewhere. The MCNP5 model-based neutron spectrum indicates that the maximum expected fast neutron flux is at a neutron energy of ~1 MeV. In addition, the MCNP5 model provided information on gamma flux to be expected in this preliminary FNPB design; specifically, in the sample holder, the gamma flux is to be expected to be around 108 γ/cm 2s, delivering a gamma dose of 4.54×103 rem/hr. This value is one to two orders of magnitudes below the gamma

  1. A preliminary area survey of neutron radiation levels associated with the NASA variable energy cyclotron horizontal neutron delivery system

    NASA Technical Reports Server (NTRS)

    Roberts, W. K.; Leonard, R. F.

    1976-01-01

    The 25 MeV deuteron beam from the NASA variable energy cyclotron incident on a thick beryllium target will deliver a tissue neutron dose rate of 2.14 rad micron A-min at a source to skin distance of 125 cm. A neutron survey of the existing hallways with various shielding configurations made during operating of the horizontal neutron delivery system indicates that minimal amounts of additional neutron shielding material are required to provide a low level radiation environment within a self-contained neutron therapy control station. Measurements also indicate that the primary neutron distribution delivered by a planned vertical delivery system will be minimally perturbed by neutrons backscattered from the floor.

  2. Self Instructional Material in Physiology: A Preliminary Evaluation.

    ERIC Educational Resources Information Center

    Davies, Mary

    1978-01-01

    Examines the preliminary evaluation of self-instructional material in physiology designed as remedial work by medical students. The materials are now used by science, veterinary, dental, and postgraduate medical students and have been distributed to 20 countries. Evaluation results indicate the materials are effective methods of study.

  3. Neutron-emission measurements at a white neutron source

    SciTech Connect

    Haight, Robert C

    2010-01-01

    Data on the spectrum of neutrons emittcd from neutron-induced reactions are important in basic nuclear physics and in applications. Our program studies neutron emission from inelastic scattering as well as fission neutron spectra. A ''white'' neutron source (continuous in energy) allows measurements over a wide range of neutron energies all in one experiment. We use the tast neutron source at the Los Alamos Neutron Science Center for incident neutron energies from 0.5 MeV to 200 MeV These experiments are based on double time-of-flight techniques to determine the energies of the incident and emitted neutrons. For the fission neutron measurements, parallel-plate ionization or avalanche detectors identify fission in actinide samples and give the required fast timing pulse. For inelastic scattering, gamma-ray detectors provide the timing and energy spectroscopy. A large neutron-detector array detects the emitted neutrons. Time-of-flight techniques are used to measure the energies of both the incident and emitted neutrons. Design considerations for the array include neutron-gamma discrimination, neutron energy resolution, angular coverage, segmentation, detector efficiency calibration and data acquisition. We have made preliminary measurements of the fission neutron spectra from {sup 235}U, {sup 238}U, {sup 237}Np and {sup 239}Pu. Neutron emission spectra from inelastic scattering on iron and nickel have also been investigated. The results obtained will be compared with evaluated data.

  4. Preliminary energy-filtering neutron imaging with time-of-flight method on PKUNIFTY: A compact accelerator based neutron imaging facility at Peking University

    NASA Astrophysics Data System (ADS)

    Wang, Hu; Zou, Yubin; Wen, Weiwei; Lu, Yuanrong; Guo, Zhiyu

    2016-07-01

    Peking University Neutron Imaging Facility (PKUNIFTY) works on an accelerator-based neutron source with a repetition period of 10 ms and pulse duration of 0.4 ms, which has a rather low Cd ratio. To improve the effective Cd ratio and thus improve the detection capability of the facility, energy-filtering neutron imaging was realized with the intensified CCD camera and time-of-flight (TOF) method. Time structure of the pulsed neutron source was firstly simulated with Geant4, and the simulation result was evaluated with experiment. Both simulation and experiment results indicated that fast neutrons and epithermal neutrons were concentrated in the first 0.8 ms of each pulse period; meanwhile in the period of 0.8-2.0 ms only thermal neutrons existed. Based on this result, neutron images with and without energy filtering were acquired respectively, and it showed that detection capability of PKUNIFTY was improved with setting the exposure interval as 0.8-2.0 ms, especially for materials with strong moderating capability.

  5. Naturalistic Evaluation--One Case. Preliminary Draft.

    ERIC Educational Resources Information Center

    Williams, David

    The purpose of this paper is to summarize some of the author's logical and empirical reflections on the practice of using naturalistic techniques to conduct evaluations. The main assertion to be supported by these reflections is that naturalistic evaluation is possible and in some cases powerful. This assertion is supported through a review of (1)…

  6. Evaluation of neutron spectrometer techniques for ITER using synthetic data

    NASA Astrophysics Data System (ADS)

    Andersson Sundén, E.; Ballabio, L.; Cecconello, M.; Conroy, S.; Ericsson, G.; Johnson, M. Gatu; Gorini, G.; Hellesen, C.; Ognissanto, F.; Ronchi, E.; Sjöstrand, H.; Tardocchi, M.; Weiszflog, M.

    2013-02-01

    A neutron spectrometer at ITER is expected to provide estimates of plasma parameters such as ion temperature, Ti, fuel ion ratio, nt/nd, and Qthermal/Qtot, with 10-20% precision at a time resolution, Δt, of at least 100 ms. The present paper describes a method for evaluating different neutron spectroscopy techniques based on their instrumental response functions and synthetic measurement data. We include five different neutron spectrometric techniques with realistic response functions, based on simulations and measurements where available. The techniques are magnetic proton recoil, thin-foil proton recoil, gamma discriminating organic scintillator, diamond and time-of-flight. The reference position and line of sight of a high resolution neutron spectrometer on ITER are used in the study. ITER plasma conditions are simulated for realistic operating scenarios. The ITER conditions evaluated are beam and radio frequency heated and thermal deuterium-tritium plasmas. Results are given for each technique in terms of the estimated time resolution at which the parameter determination can be made within the required precision (here 10% for Ti and the relative intensities of NB and RF emission components). It is shown that under the assumptions made, the thin-foil techniques out-perform the other spectroscopy techniques in practically all measurement situations. For thermal conditions, the range of achieved Δt in the determination of Ti varies in time scales from ms (for the magnetic and thin-foil proton recoil) to s (for gamma discriminating organic scintillator).

  7. Quantitative evaluation of bronchial enhancement: preliminary observations

    NASA Astrophysics Data System (ADS)

    Odry, Benjamin L.; Kiraly, Atilla P.; Novak, Carol L.; Naidich, David P.; Godoy, Myrna C. B.; Schmidt, Bernhard

    2010-03-01

    It has been known for several years that airflow limitations in the small airways may be an important contributor to Chronic Obstructive Pulmonary Disease (COPD). Quantification of wall thickness has lately gained attention thanks to the use of high resolution CT, with novel approaches focusing on automated methods that can substitute for visual assessment [1, 2]. While increased thickening of the wall is considered evidence of inflammatory disease, we hypothesize that there may be additional ways to detect and quantify inflammation, specifically the uptake of contrast material. In this preliminary investigation, we selected patients with documented chronic airway inflammation, and for whom pre and post contrast datasets were available. On targeted reconstruction of right upper and lower lobes, we selected airways with no connections to surrounding structures, and used a modified Full-Width-Half-Max method for quantification of lumen diameter, wall thickness, and wall density. Matching airway locations on the pre- and postcontrast cases were compared. Airways from patients without airway disease served as a control. Results for the airway disease cases showed an average enhancement of 72 HU within the airway walls, with a standard deviation of 59 HU. In the control group the average enhancement was 16 HU with standard deviation of 22 HU. While this study is limited in number of cases, we hypothesize that quantification of contrast uptake is an additional factor to consider in assessing airway inflammation. At the same time we are currently investigating whether enhancement can be measured via a "contrast" map created with dual energy scanning, where a 3-value decomposition algorithm differentiates iodine from other materials. This technique would eliminate both the need for a pre-contrast scan, and the task of matching airway locations on pre- and post- scans.

  8. Superconducting Gamma/Neutron Spectrometer Task 1 Completion Report Evaluation of Candidate Neutron-Sensitive Materials

    SciTech Connect

    Bell, Z.W.; Lamberti, V.E.

    2002-06-20

    A review of the scientific literature regarding boron- and lithium-containing compounds was completed. Information such as Debye temperature, heat capacity, superconductivity properties, physical and chemical characteristics, commercial availability, and recipes for synthesis was accumulated and evaluated to develop a list of neutron-sensitive materials likely to perform properly in the spectrometer. The best candidate borides appear to be MgB{sub 2} (a superconductor with T{sub c} = 39 K), B{sub 6}Si, B{sub 4}C, and elemental boron; all are commercially available. Among the lithium compounds are LiH, LiAl, Li{sub 12}Si{sub 7}, and Li{sub 7}Sn{sub 2}. These materials have or are expected to have high Debye temperatures and sufficiently low heat capacities at 100 mK to produce a useful signal. The responses of {sup 10}B and {sup 6}Li to a fission neutron spectrum were also estimated. These demonstrated that the contribution of scattering events is no more than 3% in a boron-based system and 1.5% in a lithium-based system. This project is concerned with the development of materials for use in a cryogenic neutron spectrometer and is complementary to work in progress by Labov at LLNL to develop a cryogenic gamma ray spectrometer. Refrigeration to 100 mK lowers the heat capacity of these materials to the point that the energy of absorbed gamma and x rays, nuclei scattered by fast neutrons, and ions from (n, {alpha}) reactions produce a measurable heat pulse, from which the energy of the incident radiation may be deduced. The objective of this project is the discovery, fabrication, and testing of candidate materials with which a cryogenic neutron spectrometer may be realized.

  9. Parametric Evaluation of Active Neutron Interrogation for the Detection of Shielded Highly-Enriched Uranium in the Field

    SciTech Connect

    D. L. Chcihester; E. H. Seabury; S. J. Thompson; R. R. C. Clement

    2011-10-01

    Parametric studies using numerical simulations are being performed to assess the performance capabilities and limits of active neutron interrogation for detecting shielded highly enriched uranium (HEU). Varying the shield material, HEU mass, HEU depth inside the shield, and interrogating neutron source energy, the simulations account for both neutron and photon emission signatures from the HEU with resolution in both energy and time. The results are processed to represent different irradiation timing schemes and several different classes of radiation detectors, and evaluated using a statistical approach considering signal intensity over background. This paper describes the details of the modeling campaign and some preliminary results, weighing the strengths of alternative measurement approaches for the different irradiation scenarios.

  10. A Long-Pulse Spallation Source at Los Alamos: Facility description and preliminary neutronic performance for cold neutrons

    SciTech Connect

    Russell, G.J.; Weinacht, D.J.; Pitcher, E.J.; Ferguson, P.D.

    1998-03-01

    The Los Alamos National Laboratory has discussed installing a new 1-MW spallation neutron target station in an existing building at the end of its 800-MeV proton linear accelerator. Because the accelerator provides pulses of protons each about 1 msec in duration, the new source would be a Long Pulse Spallation Source (LPSS). The facility would employ vertical extraction of moderators and reflectors, and horizontal extraction of the spallation target. An LPSS uses coupled moderators rather than decoupled ones. There are potential gains of about a factor of 6 to 7 in the time-averaged neutron brightness for cold-neutron production from a coupled liquid H{sub 2} moderator compared to a decoupled one. However, these gains come at the expense of putting ``tails`` on the neutron pulses. The particulars of the neutron pulses from a moderator (e.g., energy-dependent rise times, peak intensities, pulse widths, and decay constant(s) of the tails) are crucial parameters for designing instruments and estimating their performance at an LPSS. Tungsten is the reference target material. Inconel 718 is the reference target canister and proton beam window material, with Al-6061 being the choice for the liquid H{sub 2} moderator canister and vacuum container. A 1-MW LPSS would have world-class neutronic performance. The authors describe the proposed Los Alamos LPSS facility, and show that, for cold neutrons, the calculated time-averaged neutronic performance of a liquid H{sub 2} moderator at the 1-MW LPSS is equivalent to about 1/4th the calculated neutronic performance of the best liquid D{sub 2} moderator at the Institute Laue-Langevin reactor. They show that the time-averaged moderator neutronic brightness increases as the size of the moderator gets smaller.

  11. A Preliminary Rubric Design to Evaluate Mixed Methods Research

    ERIC Educational Resources Information Center

    Burrows, Timothy J.

    2013-01-01

    With the increase in frequency of the use of mixed methods, both in research publications and in externally funded grants there are increasing calls for a set of standards to assess the quality of mixed methods research. The purpose of this mixed methods study was to conduct a multi-phase analysis to create a preliminary rubric to evaluate mixed…

  12. Outline and Preliminary Evaluation of the Classical Digital Library Model.

    ERIC Educational Resources Information Center

    MacCall, Steven L.; Cleveland, Ana D.; Gibson, Ian E.

    1999-01-01

    Outlines the classical digital library model, which is derived from traditional practices of library and information science professionals, as an alternative to the database retrieval model. Reports preliminary results from an evaluation study of library and information professionals and endusers involved with primary care medicine. (AEF)

  13. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    SciTech Connect

    Chandler, K.; Eudy, L.

    2008-10-01

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  14. Overview of recent U235 neutron cross section evaluation work

    SciTech Connect

    Lubitz, C.

    1998-10-01

    This report is an overview (through 1997) of the U235 neutron cross section evaluation work at Oak Ridge National Laboratory (ORNL), AEA Technology (Harwell) and Lockheed Martin Corp.-Schenectady (LMS), which has influenced, or appeared in, ENDF/B-VI through Release 5. The discussion is restricted to the thermal and resolved resonance regions, apart from some questions about the unresolved region which still need investigation. The important role which benchmark testing has played will be touched on.

  15. Evaluation of Tungsten Neutron Cross Sections in the Resolved Resonance Regions

    SciTech Connect

    Pigni, Marco T; Leal, Luiz C; Dunn, Michael E; Guber, Klaus H; Emiliani, F.; Kopecky, S.; Lampoudis, C.; Schillebeeckx, P.; Siegler, P.

    2014-01-01

    We generated a preliminary set of resonance parameters for 182-184,186W in the neutron energy range of thermal up to several keV. The evaluation methodology uses the Reich-Moore approximation to t, with the R-matrix code SAMMY, the high-resolution measurements performed in 2010 and 2012 at the GEel LINear Accelerator (GELINA) facility. Particularly for 183W, the transmission data and the capture cross sections calculated with the set of resonance parameters are compared with the experimental values, and some of the average properties of the resonance parameters are discussed. In the analyzed energy range, this work almost doubles the existing resolved resonance evaluations in the ENDF/B-VII.1 library. The analysis of the performance of the calculated cross sections based on criticality benchmarks is still in progress and it is only briefly discussed.

  16. Hydrogen-enrichment-concept preliminary evaluation

    NASA Technical Reports Server (NTRS)

    Ecklund, E. E.

    1975-01-01

    A hydrogen-enriched fuels concept for automobiles is described and evaluated in terms of fuel consumption and engine exhaust emissions through multicylinder (V-8) automotive engine/hydrogen generator tests, single cylinder research engine (CFR) tests, and hydrogen-generator characterization tests. Analytical predictions are made of the fuel consumption and NO/sub x/ emissions which would result from anticipated engine improvements. The hydrogen-gas generator, which was tested to quantify its thermodynamic input-output relationships was used for integrated testing of the V-8 engine and generator.

  17. Preliminary clinical results from U.S. fast neutron teletherapy studies.

    PubMed

    Parker, R G; Berry, H C; Caderao, J B; Gerdes, A J; Hussey, D H; Ornitz, R; Rogers, C C

    1977-10-01

    Over 700 patients with cancer have been treated with fast neutron beams since 1972 in three U.S. programs at the M.D. Anderson-TAMVEC (Houston and College Station, Texas), University of Washington (Seattle, Washington), and MANTA (Naval Research Laboratory, Washington, D.C.). Clinical applications are about to start at the Fermilab (Batavia, Illinois) and Cleveland Clinic-NASA (Cleveland, Ohio). To date, studies have included: 1) effects of different treatment patterns and doses; 2) responses of several tumor types at many anatomic sites; and 3) acute and long-term normal tissue tolerances. Responses of several cancers, such as extensive epidermoid carcinoma of the cervix and "fixed" metastatic cervical adenopathy, have been encouraging. In patients with glioblastoma multiforme, good tumor responses have not lengthened survival compared with the following conventional radiation therapy. Both local tumor control and "cure" have been compromised by the inclusion of patients with very extensive cancers. In general, treatment has been well tolerated. These preliminary studies provide the basis for planned clinical trials.

  18. Evaluating the 239Pu prompt fission neutron spectrum induced by thermal to 30 MeV neutrons

    DOE PAGES

    Neudecker, Denise; Talou, Patrick; Kawano, Toshihiko; Kahler, Albert Comstock; Rising, Michael Evan; White, Morgan Curtis

    2016-03-15

    We present a new evaluation of the 239Pu prompt fission neutron spectrum (PFNS) induced by thermal to 30 MeV neutrons. Compared to the ENDF/B-VII.1 evaluation, this one includes recently published experimental data as well as an improved and extended model description to predict PFNS. For instance, the pre-equilibrium neutron emission component to the PFNS is considered and the incident energy dependence of model parameters is parametrized more realistically. Experimental and model parameter uncertainties and covariances are estimated in detail. Also, evaluated covariances are provided between all PFNS at different incident neutron energies. In conclusion, selected evaluation results and first benchmarkmore » calculations using this evaluation are briefly discussed.« less

  19. Evaluating the 239Pu Prompt Fission Neutron Spectrum Induced by Thermal to 30 MeV Neutrons

    NASA Astrophysics Data System (ADS)

    Neudecker, D.; Talou, P.; Kawano, T.; Kahler, A. C.; Rising, M. E.; White, M. C.

    2016-03-01

    We present a new evaluation of the 239Pu prompt fission neutron spectrum (PFNS) induced by thermal to 30 MeV neutrons. Compared to the ENDF/B-VII.1 evaluation, this one includes recently published experimental data as well as an improved and extended model description to predict PFNS. For instance, the pre-equilibrium neutron emission component to the PFNS is considered and the incident energy dependence of model parameters is parametrized more realistically. Experimental and model parameter uncertainties and covariances are estimated in detail. Also, evaluated covariances are provided between all PFNS at different incident neutron energies. Selected evaluation results and first benchmark calculations using this evaluation are briefly discussed.

  20. Holmium:YAG laser stapedotomy: preliminary evaluation

    NASA Astrophysics Data System (ADS)

    Stubig, Ingrid M.; Reder, Paul A.; Facer, G. W.; Rylander, Henry G.; Welch, Ashley J.

    1993-07-01

    This study investigated the use of a pulsed Holmium:YAG ((lambda) equals 2.09 micrometers ) laser- fiber microsurgical system for laser stapedotomy. This system ablates human stapes bones effectively with minimal thermal damage. The study was designed to determine the effectiveness of the Ho:YAG laser (Schwartz Electro Optics, Inc., Orlando, FL) for stapedotomy and to evaluate temperature changes within the cochlea during the ablation process. Human cadaveric temporal bones were obtained and the stapes portion of the ossicular chain was removed. A 200 micrometers diameter low OH quartz fiber was used to irradiate these stapes bones in an air environment. The laser was pulsed at 2 Hz, 250 microsecond(s) ec pulse width and an irradiance range of 100 - 240 J/cm2 was used to ablate holes in the stapes footplate. The resultant stapedotomies created had smooth 300 micrometers diameter holes with a minimum of circumferential charring. Animal studies in-vivo were carried out in chinchillas to determine the caloric spread within the cochlea. A 0.075 mm Type T thermocouple was placed in the round window. Average temperature change during irradiation of the stapes footplate recorded in the round window was 3.6 degree(s)C. The data suggest that stapedotomy using the Ho:YAG laser can result in a controlled ablation of the stapes footplate with minimal thermal damage to the surrounding stapes. Optical coupling using fiberoptic silica fibers is an ideal method for delivering laser energy to the stapes during stapedotomy.

  1. Non destructive multi elemental analysis using prompt gamma neutron activation analysis techniques: Preliminary results for concrete sample

    SciTech Connect

    Dahing, Lahasen Normanshah; Yahya, Redzuan; Yahya, Roslan; Hassan, Hearie

    2014-09-03

    In this study, principle of prompt gamma neutron activation analysis has been used as a technique to determine the elements in the sample. The system consists of collimated isotopic neutron source, Cf-252 with HPGe detector and Multichannel Analysis (MCA). Concrete with size of 10×10×10 cm{sup 3} and 15×15×15 cm{sup 3} were analysed as sample. When neutrons enter and interact with elements in the concrete, the neutron capture reaction will occur and produce characteristic prompt gamma ray of the elements. The preliminary result of this study demonstrate the major element in the concrete was determined such as Si, Mg, Ca, Al, Fe and H as well as others element, such as Cl by analysis the gamma ray lines respectively. The results obtained were compared with NAA and XRF techniques as a part of reference and validation. The potential and the capability of neutron induced prompt gamma as tool for multi elemental analysis qualitatively to identify the elements present in the concrete sample discussed.

  2. Recent Work Leading Towards a New Evaluation of the Neutron Standards

    SciTech Connect

    Carlson, A.D.; Pronyaev, V.G.; Capote, R.; Hale, G.M.; Hambsch, F.-J.; Kawano, T.; Kunieda, S.; Mannhart, W.; Nelson, R.O.; Neudecker, D.; Schillebeeckx, P.; Simakov, S.; Smith, D.L.; Talou, P.; Tao, X.; Wallner, A.; Wang, W.

    2015-01-15

    A new version of the ENDF/B library has been planned. The first step in producing this new library is evaluating the neutron standards. An evaluation is now underway with support from a Data Development Project of the IAEA. In addition to the neutron cross section standards, new evaluations are being done for prompt fission neutron spectra and a number of reference data. Efforts have been made to handle uncertainties in a proper way in these evaluations.

  3. Preliminary reliability evaluation of flip chip on flex interconnect technology

    NASA Technical Reports Server (NTRS)

    Shaw, Jack J.; Virmani, Naresh

    1997-01-01

    The study was carried out to evaluate the flip-chip-on-flex (FCOF) interconnection process in order to determine its feasibility for space flight applications. The key objectives were to: develop and apply simple and cost effective process steps needed to manufacture FCOFs and build test samples; perform a preliminary technology validation, and determine any initial environmental or application risks. The FCOF was shown to be simpler and more economical than other chip interconnection schemes.

  4. Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites

    SciTech Connect

    Newsome G, Snead L, Hinoki T, Katoh Y, Peters D

    2007-03-26

    The effects of fast neutron irradiation on SiC and SiC composites have been studied. The materials used were chemical vapor deposition (CVD) SiC and SiC/SiC composites reinforced with either Hi-Nicalon{trademark} Type-S, Hi-Nicalon{trademark} or Sylramic{trademark} fibers fabricated by chemical vapor infiltration. Statistically significant numbers of flexural samples were irradiated up to 4.6 x 10{sup 25} n/m{sup 2} (E>0.1 MeV) at 300, 500 and 800 C in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Dimensions and weights of the flexural bars were measured before and after the neutron irradiation. Mechanical properties were evaluated by four point flexural testing. Volume increase was seen for all bend bars following neutron irradiation. Magnitude of swelling depended on irradiation temperature and material, while it was nearly independent of irradiation fluence over the fluence range studied. Flexural strength of CVD SiC increased following irradiation depending on irradiation temperature. Over the temperature range studied, no significant degradation in mechanical properties was seen for composites fabricated with Hi-Nicalon{trademark} Type-S, while composites reinforced with Hi-Nicalon{trademark} or Sylramic fibers showed significant degradation. The effects of irradiation on the Weibull failure statistics are also presented suggesting a reduction in the Weibull modulus upon irradiation. The cause of this potential reduction is not known.

  5. [Evaluation of preliminary grades and credits in nurse training programs].

    PubMed

    Darmann-Finck, Ingrid; Duveneck, Nicole

    2016-01-01

    In the federal state of Bremen preliminary grades were included to the extent of 25 % in written, oral and practical final grades during the time period 2009-2014. The evaluation focuses on the effects of preliminary grades on the scale of final grades and the performance of learners as well as on the assessment of the appropriateness of final grades. A mixed-methods design was employed that consisted of a quasi-experimental study comprising of surveys of students and teachers of comparative and model courses as well as a qualitative study using group discussions. The results confirm that preliminary grades lead to a minimal improvement of the final grades of some exclusively low-achieving students. The assessment of appropriateness hardly changed. From both learners' and teachers' point of view there is still great dissatisfaction concerning the practical final grades. With regard to learning habits an increased willingness to learn new skills on the one hand and a partly increased performance pressure on the other hand were demonstrated. On the basis of these research results, the authors recommend the regular introduction of preliminary marks into the nursing training. PMID:27480188

  6. Improving Natural Uranium Utilization By Using Thorium in Low Moderation PWRs - A Preliminary Neutronic Scoping Study

    SciTech Connect

    Gilles Youinou; Ignacio Somoza

    2010-10-01

    The Th-U fuel cycle is not quite self-sustainable when used in water-cooled reactors and with fuel burnups higher than a few thousand of MWd/t characteristic of CANDU reactors operating with a continuous refueling. For the other industrially mature water-cooled reactors (i.e. PWRs and BWRs) it is economically necessary that the fuel has enough reactivity to reach fuel burnups of the order of a few tens of thousand of MWd/t. In this particular case, an additional input of fissile material is necessary to complement the bred fissile U-233. This additional fissile material could be included in the form of Highly Enriched Uranium (HEU) at the fabrication of the Th-U fuel. The objective of this preliminary neutronic scoping study is to determine (1) how much HEU and, consequently, how much natural uranium is necessary in such Th-U fuel cycle with U recycling and (2) how much TRansUranics (TRU=Pu, Np, Am and Cm) are produced. These numbers are then compared with those of a standard UO2 PWR. The thorium reactors considered have a homogeneous hexagonal lattice made up of the same (Th-U)O2 pins. Furthermore, at this point, we are not considering the use of blankets inside or outside the core. The lattice pitch has been varied to estimate the effect of the water-to-fuel volume ratio, and light water as well as heavy water have been considered. For most cases, an average burnup at discharge of 45,000 MWd/t has been considered.

  7. Preliminary neutronic study of D{sub 2}O-Cooled high conversion PWRs

    SciTech Connect

    Hiruta, Hikaru; Youinou, G.

    2013-07-01

    This paper presents a preliminary neutronics analysis of tight-pitch D{sub 2}O-cooled high-conversion pressurised water reactors (HPWR) loaded with MOX fuel aiming at high Pu conversion and negative void coefficient. SCALE6.1 code has been exclusively utilized for this study. The analyses are performed in two separate parts. The first part of this paper investigates the performance of axial and internal blankets and seeks break-even or near-breeder core even without the presence of radial blankets. The analyses showed that the relative Pu mass balance was effectively increased by the addition of the axial blanket. The addition of only 4 cm of blanket resulted in the 4000 pcm increase in the void coefficient. Thus, the presence of the axial blanket made the void coefficient hardly negative. The second part of this paper performs sensitivity and uncertainty analyses of integral parameters (k{sub eff} and void coefficient) for selected systems in order to analyze the characters of this high-conversion PWR from different aspects. The uncertainty analysis of k{sub eff} showed that its breakup contributions for D{sub 2}O-HPWR were very similar to other fast systems (SFR and H{sub 2}O-HPWR) such that the key contributors were {sup 238}U inelastic and {sup 239}Pu ν-bar. However, breakup uncertainties of void coefficients showed that while those of D{sub 2}O-HPWR resembled to H{sub 2}O-HPWR, Na elastic became the significant contributor of the void coefficient uncertainty of SFR. Also sensitivity profiles of {sup 238}U inelastic and {sup 239}Pu ν-bar to the void coefficient revealed that those of SFR were quite dissimilar to both HPWRs. The study also found that while the absolute values of void coefficient uncertainty for D{sub 2}O-HPWR were invariant through the burnup, its percentage uncertainty was significantly increased.

  8. Improved Neutron Capture Gamma-Ray Data and Evaluation

    NASA Astrophysics Data System (ADS)

    Sleaford, B.; Basunia, Shamsuzzoha; Becvar, F.; Belgya, T.; Bernstein, L.; Choi, H.; Escher, J.; Firestone, R.; Genreith, C.; Gunsing, F.; Hurst, A.; Krticka, M.; Revay, Z.; Rossbach, M.; Summers, N.; Szentmiklosi, L.

    2014-09-01

    The neutron-capture reaction is of fundamental use in identifying and analyzing the gamma-ray spectrum from an unknown object as it gives a fingerprint of which isotopes are present. Many isotopes have capture gamma lines from 5-10 MeV potentially making them easier to detect against background lines. There are data gaps in the Evaluated Nuclear Data File (ENDF) libraries used by modeling codes (the actinides have no lines for example) and we are filling these with the Evaluated Gamma-ray Activation File (EGAF), using an IAEA atlas of reactor measured lines and cross sections for over 260 isotopes. For medium to heavy nuclei, the unresolved part of the gamma cascades is not measured and are modeled using the statistical nuclear structure code Dicebox [1,2]. ENDF libraries require cross sections for neutron energies up to 20 MeV and we plan to continue this approach through the resolved resonance region. The neutron-capture reaction is of fundamental use in identifying and analyzing the gamma-ray spectrum from an unknown object as it gives a fingerprint of which isotopes are present. Many isotopes have capture gamma lines from 5-10 MeV potentially making them easier to detect against background lines. There are data gaps in the Evaluated Nuclear Data File (ENDF) libraries used by modeling codes (the actinides have no lines for example) and we are filling these with the Evaluated Gamma-ray Activation File (EGAF), using an IAEA atlas of reactor measured lines and cross sections for over 260 isotopes. For medium to heavy nuclei, the unresolved part of the gamma cascades is not measured and are modeled using the statistical nuclear structure code Dicebox [1,2]. ENDF libraries require cross sections for neutron energies up to 20 MeV and we plan to continue this approach through the resolved resonance region. This work is performed in part under the auspices of the USDoE by LLNL under Contract DE-AC52-07NA27344.

  9. Meteorologic factors and subjective sleep continuity: a preliminary evaluation

    NASA Astrophysics Data System (ADS)

    Pandey, Juhi; Grandner, Michael; Crittenden, Crista; Smith, Michael T.; Perlis, Michael L.

    2005-01-01

    Little research has been undertaken to evaluate whether environmental factors other than bright light influence the individual’s ability to initiate and maintain sleep. In the present analyses, nine meteorologic variables were evaluated for their possible relationship to self-reported sleep continuity in a sample of 43 subjects over a period of 105 days. In this preliminary analysis, high barometric pressure, low precipitation, and lower temperatures were significantly correlated with good sleep continuity. Interestingly, ambient light and lunar phase were not found to be strongly associated sleep diary measures.

  10. Meteorologic factors and subjective sleep continuity: a preliminary evaluation.

    PubMed

    Pandey, Juhi; Grandner, Michael; Crittenden, Crista; Smith, Michael T; Perlis, Michael L

    2005-01-01

    Little research has been undertaken to evaluate whether environmental factors other than bright light influence the individual's ability to initiate and maintain sleep. In the present analyses, nine meteorologic variables were evaluated for their possible relationship to self-reported sleep continuity in a sample of 43 subjects over a period of 105 days. In this preliminary analysis, high barometric pressure, low precipitation, and lower temperatures were significantly correlated with good sleep continuity. Interestingly, ambient light and lunar phase were not found to be strongly associated sleep diary measures. PMID:15316762

  11. Dose evaluation of boron neutron capture synovectomy using the THOR epithermal neutron beam: a feasibility study

    NASA Astrophysics Data System (ADS)

    Wu, Jay; Chang, Shu-Jun; Chuang, Keh-Shih; Hsueh, Yen-Wan; Yeh, Kuan-Chuan; Wang, Jeng-Ning; Tsai, Wen-Pin

    2007-03-01

    Rheumatoid arthritis is one of the most common epidemic diseases in the world. For some patients, the treatment with steroids or nonsteroidal anti-inflammatory drugs is not effective, thus necessitating physical removal of the inflamed synovium. Alternative approaches other than surgery will provide appropriate disease control and improve the patient's quality of life. In this research, we evaluated the feasibility of conducting boron neutron capture synovectomy (BNCS) with the Tsing Hua open-pool reactor (THOR) as a neutron source. Monte Carlo simulations were performed with arthritic joint models and uncertainties were within 5%. The collimator, reflector and boron concentration were optimized to reduce the treatment time and normal tissue doses. For the knee joint, polyethylene with 40%-enriched Li2CO3 was used as the collimator material, and a rear reflector of 15 cm thick graphite and side reflector of 10 cm thick graphite were chosen. The optimized treatment time was 5.4 min for the parallel-opposed irradiation. For the finger joint, polymethyl methacrylate was used as the reflector material. The treatment time can be reduced to 3.1 min, while skin and bone doses can be effectively reduced by approximately 9% compared with treatment using the graphite reflector. We conclude that using THOR as a treatment modality for BNCS could be a feasible alternative in clinical practice.

  12. Preliminary study of neutron absorption by concrete with boron carbide addition

    NASA Astrophysics Data System (ADS)

    Abdullah, Yusof; Ariffin, Fatin Nabilah Tajul; Hamid, Roszilah; Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal; Ahmad, Sahrim; Mohamed, Abdul Aziz

    2014-02-01

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  13. Preliminary study of neutron absorption by concrete with boron carbide addition

    SciTech Connect

    Abdullah, Yusof Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal; Ariffin, Fatin Nabilah Tajul; Ahmad, Sahrim; Hamid, Roszilah; Mohamed, Abdul Aziz

    2014-02-12

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  14. Evaluation of Neutron Poison Materials for DOE SNF Disposal Systems

    SciTech Connect

    Vinson, D.W.; Caskey, G.R. Jr.; Sindelar, R.L.

    1998-09-01

    Aluminum-based spent nuclear fuel (Al-SNF) from foreign and domestic research reactors is being consolidated at the Savannah River Site (SRS) for ultimate disposal in the Mined Geologic Disposal System (MGDS). Most of the aluminum-based fuel material contains highly enriched uranium (HEU) (more than 20 percent 235U), which challenges the preclusion of criticality events for disposal periods exceeding 10,000 years. Recent criticality analyses have shown that the addition of neutron absorbing materials (poisons) is needed in waste packages containing DOE SNF canisters fully loaded with Al-SNF under flooded and degraded configurations to demonstrate compliance with the requirement that Keff less than 0.95. Compatibility of poison matrix materials and the Al-SNF, including their relative degradation rate and solubility, are important to maintain criticality control. An assessment of the viability of poison and matrix materials has been conducted, and an experimental corrosion program has been initiated to provide data on degradation rates of poison and matrix materials and Al-SNF materials under repository relevant vapor and aqueous environments. Initial testing includes Al6061, Type 316L stainless steel, and A516Gr55 in synthesized J-13 water vapor at 50 degrees C, 100 degrees C, and 200 degrees C and in condensate water vapor at 100 degrees C. Preliminary results are presented herein.

  15. Evaluation of the NDP (neutron diagnostic probe) system

    SciTech Connect

    Pentaleri, E.A.; Eisen, Y.Y.

    1990-12-01

    The neutron diagnostic probe (NDP), an explosive detection system developed by Consolidated Controls Corporation and based on the associated-alpha-particle technique, was evaluated. Although many problems were found with the prototype system that make it useless for most practical applications, the NDP system may be considered a successful proof-of-principle for the basic explosive detection system design. In addition to evaluating the design and performance of the present system, models were developed to estimate the performance that might reasonably be expected from full scale systems of different conceptual design. Specific examples involved various types of bulk and sheet explosives contained in a suitcase and a large crate. Also considered were the effects of innocuous materials surrounding explosives in different scenarios, including the deliberate use of shielding materials as a countermeasure to detection. 11 refs., 46 figs., 24 tabs.

  16. Systematic evaluation of neutron shielding effects for materials

    SciTech Connect

    Ueki, K.; Ohashi, A.; Nariyama, N.; Nagayama, S.; Fujita, T.; Hattori, K.; Anayama, Y.

    1996-11-01

    Three types of experiments with a {sup 252}Cf neutron source are proposed to evaluate systematically the neutron shielding effects of a material. The type 1 experiment deals with each shielding material alone, the type 2 experiment combines a shielding material and a structural material, and the type 3 experiment constructs the optimization with the materials used in the type 2 experiment. In the stainless steel (SS) + polyethylene shielding system, because of the location of the SS slabs at the source side, the tenth layer of the polyethylene becomes approximately one-half the value as when the polyethylene is employed alone. This is the enhancement effect of the SS. In the type 3 experiment, the total thickness of the SS + polyethylene shielding system is 40 cm, and the total thicknesses of the SS and the polyethylene slabs are fixed at 25 and 15 cm thick, respectively. The minimum total dose-equivalent rate (neutron + secondary gamma rays) is observed when the polyethylene slabs are located at a 20-cm depth from the source side, with an arrangement of 20-cm-thick SS + 15-cm-thick polyethylene + 5-cm-thick and SS, and with a ratio of the maximum to the minimum dose-equivalent rate of 2.5. The shielding optimization can be constructed by combining the materials having different shielding characteristics. The experimental results of the three types of experiments are reproduced fairly well by using the continuous-energy Monte Carlo code MCNP 4A with a next-event surface crossing estimator.

  17. Neutron Reflectometry at Elevated Pressures and Temperatures - Novel P-T Cell and Preliminary Experiments

    NASA Astrophysics Data System (ADS)

    Hickmott, D.; Lerner, A. H.; Wang, P.; Majewski, J.; Taylor, M.

    2011-12-01

    Processes at mineral-fluid interfaces control a wide-range of phenomena of crucial importance in energy and environmental applications, including fluid flow, mineral precipitation and dissolution, and corrosion and scaling. In geological systems, geothermal energy production, CO2 sequestration, oil and gas production, and nuclear reactors and waste repositories, these critical mineral-fluid interactions occur at high pressures (P) and temperatures (T). Unfortunately the details of these phenomena are poorly understood because of the technical difficulties with conducting in-situ investigations of mineral/fluid interfaces at relevant geological conditions. Neutron reflectometry offers the possibility of studying fluid/solid processes in-situ at elevated Ps and Ts. In neutron reflectometry an unpolarized neutron beam (wavelength 1.5 to 16 Å) is directed at a solid/fluid (or other) interface at a glancing angle and a range of momentum transfer vectors (Q) are measured elucidating changes in material layering and fluid density within a few dozen Å of the solid/liquid interface. Neutron reflectometry is an ideal technique for investigating such processes at elevated P/T because neutrons are strongly penetrating and able to pass through robust, high P/T aluminum cells with minimal neutron attenuation. Additionally, neutrons are highly sensitive to deuterium due to its large neutron scattering cross section, allowing heavy water to be detected. Thus, neutron scattering has advantages over x-ray techniques, which cannot detect water and which cannot penetrate large-volume P cells. A new LANL neutron cell allows neutron reflectometry studies at conditions up to 200°C and 200 MPa, corresponding to a crustal depth of 6 km. The 5 in. diameter cell is constructed of anodized AA7075 aluminum with a 2 in. diameter sample chamber. The neutron cell and P system can accommodate fluid environments varying in pH and mineral and CO2 saturations. Neutron reflectometry studies will

  18. Preliminary measurements of neutrons from the D-D reaction in the COMPASS tokamak

    SciTech Connect

    Dankowski, J. Kurowski, A.; Twarog, D.; Janky, F.; Stockel, J.

    2014-08-21

    Recent results of measured fast neutrons created in the D-D reaction on the COMPASS tokamak during ohmic discharges are presented in this paper. Two different type detectors were used during experiment. He-3 detectors and bubble detectors as a support. The measurements are an introduction for neutron diagnostic on tokamak COMPASS and monitoring neutrons during discharges with Neutral Beam Injection (NBI). The He-3 counters and bubble detectors were located in two positions near tokamak vacuum chamber at a distance less than 40 cm to the centre of plasma. The neutrons flux was observed in ohmic discharges. However, analysis of our results does not indicate any clear source of neutrons production during ohmic discharges.

  19. Further Evaluation of the Neutron Resonance Transmission Analysis (NRTA) Technique for Assaying Plutonium in Spent Fuel

    SciTech Connect

    J. W. Sterbentz; D. L. Chichester

    2011-09-01

    This is an end-of-year report (Fiscal Year (FY) 2011) for the second year of effort on a project funded by the National Nuclear Security Administration's Office of Nuclear Safeguards (NA-241). The goal of this project is to investigate the feasibility of using Neutron Resonance Transmission Analysis (NRTA) to assay plutonium in commercial light-water-reactor spent fuel. This project is part of a larger research effort within the Next-Generation Safeguards Initiative (NGSI) to evaluate methods for assaying plutonium in spent fuel, the Plutonium Assay Challenge. The second-year goals for this project included: (1) assessing the neutron source strength needed for the NRTA technique, (2) estimating count times, (3) assessing the effect of temperature on the transmitted signal, (4) estimating plutonium content in a spent fuel assembly, (5) providing a preliminary assessment of the neutron detectors, and (6) documenting this work in an end of the year report (this report). Research teams at Los Alamos National Laboratory (LANL), Lawrence Berkeley National Laboratory (LBNL), Pacific Northwest National Laboratory (PNNL), and at several universities are also working to investigate plutonium assay methods for spent-fuel safeguards. While the NRTA technique is well proven in the scientific literature for assaying individual spent fuel pins, it is a newcomer to the current NGSI efforts studying Pu assay method techniques having just started in March 2010; several analytical techniques have been under investigation within this program for two to three years or more. This report summarizes work performed over a nine month period from January-September 2011 and is to be considered a follow-on or add-on report to our previous published summary report from December 2010 (INL/EXT-10-20620).

  20. Preliminary evaluation of a geothermal aquifer in Southern England

    SciTech Connect

    Burgess, W.G.

    1986-11-01

    The preliminary evaluation of the first direct-use (low enthalpy) geothermal well in the United Kingdom included core analysis, geophysical logging, and drill-stem testing. The effective aquifer is restricted to a few relatively thin loosely cemented bands in the Triassic sandstones at a depth of approximately 1660 m. With an aquifer temperature of at least 67/sup 0/C the initial assessment of transmissivity, 18 m/sup 2//day, suggested that a thermal yield of approximately 2.5 MW would be obtainable. The results are in reasonable agreement with those of a subsequent long-term production test.

  1. An Evaluation of Grazing-Incidence Optics for Neutron Imaging

    NASA Technical Reports Server (NTRS)

    Gubarev, M. V.; Ramsey, B. D.; Engelhaupt, D. E.; Burgess, J.; Mildner, D. F. R.

    2007-01-01

    The focusing capabilities of neutron imaging optic based on the Wolter-1 geometry have been successfully demonstrated with a beam of long wavelength neutrons with low angular divergence.. A test mirror was fabricated using an electroformed nickel replication process at Marshall Space Flight Center. The neutron current density gain at the focal spot of the mirror is found to be at least 8 for neutron wavelengths in the range from 6 to 20 A. Possible applications of the optics are briefly discussed.

  2. Current Issues in Nuclear Data Evaluation Methodology: {sup 235}U Prompt Fission Neutron Spectra and Multiplicity for Thermal Neutrons

    SciTech Connect

    Trkov, A.; Capote, R.; Pronyaev, V.G.

    2015-01-15

    Issues in evaluation methodology of the prompt fission neutron spectra (PFNS) and neutron multiplicity for the thermal-neutron-induced fission of the {sup 235}U are discussed. The inconsistency between the experimental differential and integral data is addressed. By using differential data as ”shape data” good consistency was achieved between available sets of differential data. Integral dosimetry data have been used to define the PFNS slope at high outgoing neutron energies, where the quality of the differential data is poor. The inclusion into the fit of measured integral (spectrum-averaged) cross sections had a very small impact in the region where differential PFNS data are abundant and accurate, but removed the discrepancy with integral data at higher neutron emission energies. All experimental data are consistently fitted giving a PFNS average energy of 2.008 MeV. The impact on criticality prediction of the newly evaluated PFNS was tested. The highly enriched {sup 235}U solution assemblies with high leakage HEU-SOL-THERM-001 and HEU-SOL-THERM-009 benchmarks are the most sensitive to the PFNS. Criticality calculations for those solutions show a significant increase in reactivity if the average neutron energy of the fission neutrons is reduced from the ENDF/B-VI.5 value of 2.03 MeV. The proposed reduction of the PFNS average energy by 1.1% can be compensated by reducing the average number of neutrons per fission ν{sup ¯} at the thermal energy to the Gwin et al. measured value. The simple least-squares PFNS fit was confirmed by a more sophisticated combined fit of differential PFNS data for {sup 233,235}U, {sup 239}Pu and {sup 252}Cf nuclides with the generalised least-squares method using the GMA and GANDR codes.

  3. Skylab neutron environment experiment (Science Demonstration SD-34 (TV108)). Description and preliminary results

    NASA Technical Reports Server (NTRS)

    Fishman, G. J.

    1974-01-01

    Neutron and proton induced radioactivity at various locations within Skylab were measured. Samples of five metals were formed into activation packets and deployed at the following locations on the Skylab 4 mission: orbital workshop film vault, water storage tank, and two opposing orbital workshop internal locations. Radioactive nuclides were produced in the packets by nuclear interactions of high-energy protons and secondary neutrons within Skylab. Low-level gamma ray spectroscopy measurements were made on the returned packets to determine the incident neutron and proton fluxes and spectra and their variations with mass distribution.

  4. Spectrum evaluation at the filter-modified neutron irradiation field for neutron capture therapy in Kyoto University Research Reactor

    NASA Astrophysics Data System (ADS)

    Sakurai, Yoshinori; Kobayashi, Tooru

    2004-10-01

    The Heavy Water Neutron Irradiation Facility of the Kyoto University Research Reactor (KUR-HWNIF) was updated in March 1996, mainly to improve the facility for neutron capture therapy (NCT). In this facility, neutron beams with various energy spectra, from almost pure thermal to epithermal, are available. The evaluation of the neutron energy spectra by multi-activation-foil method was performed as a series of the facility characterization. The spectra at the normal irradiation position were evaluated for the combinations of heavy-water thickness of the spectrum shifter and the open-close condition of the cadmium and boral filters. The initial spectra were made mainly using a two-dimensional transport code, and the final spectra were obtained using an adjusting code. For the verification of the evaluated spectra, simulation calculations using a phantom were performed on the assumption of NCT-clinical-irradiation conditions. It resulted that the calculated data for the depth neutron-flux distributions were in good agreement with the experimental ones.

  5. Evaluation of high pressure Freon decontamination. I. Preliminary tests

    SciTech Connect

    Rankin, W.N.

    1983-10-31

    High-pressure Freon blasting techniques are being evaluated for applications involving the removal of non-adherent radioactive particulate contamination at SRP. Very little waste is generated by this technique because the used Freon can be easily distilled and reused. One of the principle advantages of this technique is that decontaminated electrical equipment can be returned to service immediately without drying, unlike high-pressure water blasting techniques. Preliminary scoutin tests evaluating high-pressure Freon blasting for decontamination at SRP were carried out at Quadrex Co., Oak Ridge, TN, October 12 and 13. DWPF-type contamination (raw sludge plus volatiles) and separations area-type contamination (diluted boiling point (47.6/sup 0/C) allow it to rapidly separate from higher boiling contaminants via distillation with filtration to remove particulate material, and distillation with condensation, the solvent may be recovered for indefinite reuse while reducing the radioactive waste to a minimum. 3 references, 5 figures, 6 tables.

  6. Preliminary nondestructive evaluation manual for the space shuttle. [preliminary nondestructive evaluation

    NASA Technical Reports Server (NTRS)

    Pless, W. M.

    1974-01-01

    Nondestructive evaluation (NDE) requirements are presented for some 134 potential fracture-critical structural areas identified, for the entire space shuttle vehicle system, as those possibly needing inspection during refurbishment/turnaround and prelaunch operations. The requirements include critical area and defect descriptions, access factors, recommended NDE techniques, and descriptive artwork. Requirements discussed include: Orbiter structure, external tank, solid rocket booster, and thermal protection system (development area).

  7. Characteristic evaluation of a Lithium-6 loaded neutron coincidence spectrometer.

    PubMed

    Hayashi, M; Kaku, D; Watanabe, Y; Sagara, K

    2007-01-01

    Characteristics of a (6)Li-loaded neutron coincidence spectrometer were investigated from both measurements and Monte Carlo simulations. The spectrometer consists of three (6)Li-glass scintillators embedded in a liquid organic scintillator BC-501A, which can detect selectively neutrons that deposit the total energy in the BC-501A using a coincidence signal generated from the capture event of thermalised neutrons in the (6)Li-glass scintillators. The relative efficiency and the energy response were measured using 4.7, 7.2 and 9.0 MeV monoenergetic neutrons. The measured ones were compared with the Monte Carlo calculations performed by combining the neutron transport code PHITS and the scintillator response calculation code SCINFUL. The experimental light output spectra were in good agreement with the calculated ones in shape. The energy dependence of the detection efficiency was reproduced by the calculation. The response matrices for 1-10 MeV neutrons were finally obtained.

  8. PGNAA system preliminary design and measurement of In-Hospital Neutron Irradiator for boron concentration measurement.

    PubMed

    Zhang, Zizhu; Chong, Yizheng; Chen, Xinru; Jin, Congjun; Yang, Lijun; Liu, Tong

    2015-12-01

    A prompt gamma neutron activation analysis (PGNAA) system has been recently developed at the 30-kW research reactor In-Hospital Neutron Irradiator (IHNI) in Beijing. Neutrons from the specially designed thermal neutron beam were used. The thermal flux of this beam is 3.08×10(6) cm(-2) s(-1) at a full reactor power of 30 kW. The PGNAA system consists of an n-type high-purity germanium (HPGe) detector of 40% efficiency, a digital spectrometer, and a shielding part. For both the detector shielding part and the neutron beam shielding part, the inner layer is composed of (6)Li2CO3 powder and the outer layer lead. The boron-10 sensitivity of the PGNAA system is approximately 2.5 cps/ppm. Two calibration curves were produced for the 1-10 ppm and 10-50 ppm samples. The measurement results of the control samples were in accordance with the inductively coupled plasma atomic emission spectroscopy (ICP-AES) results.

  9. Evaluation of H*(10) using the developed spherical type neutron dose monitor.

    PubMed

    Bhuiya, S H; Yamanishi, H; Uda, T

    2010-10-01

    An instrument for evaluating the neutron ambient dose equivalent has been developed. It has the characteristic of uniform response to wide energy of neutrons. The monitor is four-layered spherically shaped, based on moderation and absorption of neutrons. Neutron dose can be evaluated from the linear combination of three specific responses of thermoluminescent dosimeters (TLDs), which are located at three depths in the moderator. TLDs were arranged between layers of two consecutive depths on 12 radial axes at even intervals so that the monitor is equally sensitive to all directions of neutrons. In order to verify the usefulness of dose evaluation by the monitor, irradiation experiments were conducted at the FRS, JAEA. The D2O-moderated 252Cf was used for the calibration of the monitor. Experiments were also conducted by using two neutron sources of 252Cf bare and 241Am-Be. As a result, the evaluated dose for each irradiation was obtained close to the actual irradiated dose. It was confirmed that the method of dose evaluation by the developed monitor can be applied to practical neutron fields where the distance of neutron source is unknown.

  10. Preliminary seal design evaluation for the Waste Isolation Pilot Plant

    SciTech Connect

    Stormont, J C

    1988-03-01

    This report presents a preliminary evaluation of design concepts for the eventual sealing of the shafts, drifts, and boreholes at the Waste Isolation Pilot Plant Facility. The purpose of the seal systems is to limit the flow of water into, through, and out of the repository. The principal design strategy involves the consolidation of crushed or granular salt in response to the closure of the excavations in salt. Other candidate seal materials are bentonite, cementitious mixtures, and possibly asphalt. Results from in situ experiments and modeling studies, as well as laboratory materials testing and related industrial experience, are used to develop seal designs for shafts, waste storage panel entryways, non-waste containing drifts, and boreholes. Key elements of the ongoing experimental program are identified. 112 refs., 25 figs., 1 tab.

  11. Preliminary safety evaluation for the plutonium stabilization and packaging system

    SciTech Connect

    Shapley, J.E., Fluor Daniel Hanford

    1997-03-14

    This Preliminary Safety Evaluation (PSE) describes and analyzes the installation and operation of the Plutonium Stabilization and Packaging System (SPS) at the Plutonium Finishing Plant (PFP). The SPS is a combination of components required to expedite the safe and timely storage of Plutonium (Pu) oxide. The SPS program will receive site Pu packages, process the Pu for storage, package the Pu into metallic containers, and safely store the containers in a specially modified storage vault. The location of the SPS will be in the 2736- ZB building and the storage vaults will be in the 2736-Z building of the PFP, as shown in Figure 1-1. The SPS will produce storage canisters that are larger than those currently used for Pu storage at the PFP. Therefore, the existing storage areas within the PFP secure vaults will require modification. Other modifications will be performed on the 2736-ZB building complex to facilitate the installation and operation of the SPS.

  12. Preliminary investigation of parasitic radioisotope production using the LANL IPF secondary neutron flux

    NASA Astrophysics Data System (ADS)

    Engle, J. W.; Kelsey, C. T.; Bach, H.; Ballard, B. D.; Fassbender, M. E.; John, K. D.; Birnbaum, E. R.; Nortier, F. M.

    2012-12-01

    In order to ascertain the potential for radioisotope production and material science studies using the Isotope Production Facility at Los Alamos National Lab, a two-pronged investigation has been initiated. The Monte Carlo for Neutral Particles eXtended (MCNPX) code has been used in conjunction with the CINDER 90 burnup code to predict neutron flux energy distributions as a result of routine irradiations and to estimate yields of radioisotopes of interest for hypothetical irradiation conditions. A threshold foil activation experiment is planned to study the neutron flux using measured yields of radioisotopes, quantified by HPGe gamma spectroscopy, from representative nuclear reactions with known thresholds up to 50 MeV.

  13. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.; Massaro, Lawrence M.; Jensen, Philip J.

    2015-09-30

    A preliminary evaluation of removing spent nuclear fuel (SNF) from 13 shutdown nuclear power reactor sites was conducted. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, San Onofre, and Vermont Yankee. The evaluation was divided into four components: (1) characterization of the SNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory, (2) a description of the on-site infrastructure and conditions relevant to transportation of SNF and GTCC waste, (3) an evaluation of the near-site transportation infrastructure and experience relevant to shipping transportation casks containing SNF and GTCC waste, including identification of gaps in information, and (4) an evaluation of the actions necessary to prepare for and remove SNF and GTCC waste. Every site was found to have at least one off-site transportation mode option for removing its SNF and GTCC waste; some have multiple options. Experience removing large components during reactor decommissioning provided an important source of information used to identify the transportation mode options for the sites. Especially important in conducting the evaluation were site visits, through which information was obtained that would not have been available otherwise. Extensive photographs taken during the site visits proved to be particularly useful in documenting the current conditions at or near the sites. It is expected that additional site visits will be conducted to add to the information presented in the evaluation.

  14. Stability evaluation and correction of a pulsed neutron generator prompt gamma activation analysis system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Source output stability is important for accurate measurement in prompt gamma neutron activation. This is especially true when measuring low-concentration elements such as in vivo nitrogen (~2.5% of body weight). We evaluated the stability of the compact DT neutron generator within an in vivo nitrog...

  15. Evaluation of thermal neutron irradiation field using a cyclotron-based neutron source for alpha autoradiography.

    PubMed

    Tanaka, H; Sakurai, Y; Suzuki, M; Masunaga, S; Mitsumoto, T; Kinashi, Y; Kondo, N; Narabayashi, M; Nakagawa, Y; Watanabe, T; Fujimoto, N; Maruhashi, A; Ono, K

    2014-06-01

    It is important to measure the microdistribution of (10)B in a cell to predict the cell-killing effect of new boron compounds in the field of boron neutron capture therapy. Alpha autoradiography has generally been used to detect the microdistribution of (10)B in a cell. Although it has been performed using a reactor-based neutron source, the realization of an accelerator-based thermal neutron irradiation field is anticipated because of its easy installation at any location and stable operation. Therefore, we propose a method using a cyclotron-based epithermal neutron source in combination with a water phantom to produce a thermal neutron irradiation field for alpha autoradiography. This system can supply a uniform thermal neutron field with an intensity of 1.7×10(9) (cm(-2)s(-1)) and an area of 40mm in diameter. In this paper, we give an overview of our proposed system and describe a demonstration test using a mouse liver sample injected with 500mg/kg of boronophenyl-alanine.

  16. Preliminary data evaluation for thermal insulation characterization testing

    SciTech Connect

    DeClue, J F; Moses, S D; Tollefson, D A

    1991-01-04

    The purpose of Thermal Insulation Characterization Testing is to provide physical data to support certain assumptions and calculational techniques used in the criticality safety calculations in Section 6 of the Safety Analysis Reports for Packaging (SARPs) for drum-type packaging for Department of Energy's (DOE) Oak Ridge Y-12 Plant, managed by Martin Marietta Energy Systems, Inc. Results of preliminary data evaluation regarding the fire-test condition reveal that realistic weight loss consideration and residual material characterization in developing calculational models for the hypothetical accident condition is necessary in order to prevent placement of unduly conservative restrictions on shipping requirements as a result of overly conservative modeling. This is particularly important for fast systems. Determination of the geometric arrangement of residual material is of secondary importance. Both the methodology used to determine the minimum thermal insulation mass remaining after the fire test and the treatment of the thermal insulation in the criticality safety calculational models requires additional evaluation. Specific testing to be conducted will provide experimental data with which to validate the mass estimates and calculational modeling techniques for extrapolation to generic drum-type containers.

  17. Preliminary safety evaluation of the advanced burner test reactor.

    SciTech Connect

    Dunn, F. E.; Fanning, T. H.; Cahalan, J. E.; Nuclear Engineering Division

    2006-09-15

    Results of a preliminary safety evaluation of the Advanced Burner Test Reactor (ABTR) pre-conceptual design are reported. The ABTR safety design approach is described. Traditional defense-in-depth design features are supplemented with passive safety performance characteristics that include natural circulation emergency decay heat removal and reactor power reduction by inherent reactivity feedbacks in accidents. ABTR safety performance in design-basis and beyond-design-basis accident sequences is estimated based on analyses. Modeling assumptions and input data for safety analyses are presented. Analysis results for simulation of simultaneous loss of coolant pumping power and normal heat rejection are presented and discussed, both for the case with reactor scram and the case without reactor scram. The analysis results indicate that the ABTR pre-conceptual design is capable of undergoing bounding design-basis and beyond-design-basis accidents without fuel cladding failures. The first line of defense for protection of the public against release of radioactivity in accidents remains intact with significant margin. A comparison and evaluation of general safety design criteria for the ABTR conceptual design phase are presented in an appendix. A second appendix presents SASSYS-1 computer code capabilities and modeling enhancements implemented for ABTR analyses.

  18. Preliminary Field Evaluation of Mercury Control Using Combustion Modifications

    SciTech Connect

    V. Lissianski; P. Maly; T. Marquez

    2005-01-22

    In this project EER conducted a preliminary field evaluation of the integrated approach for mercury (Hg) and NO{sub x} control. The approach enhanced the 'naturally occurring' Hg capture by fly ash through combustion optimization, increasing carbon in ash content, and lowering ESP temperature. The evaluation took place in Green Station Units 1 and 2 located near Henderson, Kentucky and operated by Western Kentucky Energy. Units 1 and 2 are equipped with cold-side ESPs and wet scrubbers. Green Station Units 1 and 2 typically fire two types of fuel: a bituminous coal and a blend of bituminous coals based on availability. Testing of Hg emissions in Unit 2 without reburning system in operation and at minimum OFA demonstrated that efficiencies of Hg reduction downstream of the ESP were 30-40%. Testing also demonstrated that OFA system operation at 22% air resulted in 10% incremental increase in Hg removal efficiency at the ESP outlet. About 80% of Hg in flue gas at ESP outlet was present in the oxidized form. Testing of Hg emissions under reburning conditions showed that Hg emissions decreased with LOI increase and ESP temperature decrease. Testing demonstrated that maximum Hg reduction downstream of ESP was 40-45% at ESP temperatures higher than 300 F and 60-80% at ESP temperatures lower than 300 F. The program objective to demonstrate 80% Hg removal at the ESP outlet has been met.

  19. PRELIMINARY FIELD EVALUATION OF MERCURY CONTROL USING COMBUSTION MODIFICATIONS

    SciTech Connect

    Vitali Lissianski; Antonio Marquez

    2004-02-19

    In this project General Electric Energy and Environmental Research Corporation conducts a preliminary field evaluation of a novel technology, referred to as Hg/NO{sub x}, that can reduce emissions of both mercury (Hg) and oxides of nitrogen (NO{sub x}) from coal-fired power plants. The evaluation takes place in Green Station Unit 2 operated by Western Kentucky Energy. Reduction of Hg and NO{sub x} emissions in Unit 2 is achieved using coal reburning. Activities during first project year (January 23, 2003--January 22, 2004) included measurements of baseline Hg emissions in Unit 2 and pilot-scale testing. Baseline testing of Hg emissions in Green Unit 2 has been completed. Two fuels were tested with OFA system operating at minimum air flow. Mercury emissions were measured at ESP inlet and outlet, and at the stack using Ontario Hydro revised method. Testing demonstrated that baseline Hg reductions at ESP outlet and stack were 30-45% and 70-80%, respectively. Pilot-scale testing demonstrated good agreement with baseline measurements in Unit 2. Testing showed that fuel composition had an effect on the efficiency of Hg absorption on fly ash. Maximum achieved Hg removal in reburning was close to 90%. Maximum achieved Hg reduction at air staging conditions was 60%. Testing also demonstrated that lowering ESP temperature improved efficiency of Hg removal.

  20. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.

    2013-09-30

    This report fulfills the M2 milestone M2FT-13PN0912022, “Stranded Sites De-Inventorying Report.” In January 2013, the U.S. Department of Energy (DOE) issued the Strategy for the Management and Disposal of Used Nuclear Fuel and High-Level Radioactive Waste (DOE 2013). Among the elements contained in this strategy is an initial focus on accepting used nuclear fuel from shutdown reactor sites. This focus is consistent with the recommendations of the Blue Ribbon Commission on America’s Nuclear Future, which identified removal of stranded used nuclear fuel at shutdown sites as a priority so that these sites may be completely decommissioned and put to other beneficial uses (BRC 2012). Shutdown sites are defined as those commercial nuclear power reactor sites where the nuclear power reactors have been shut down and the site has been decommissioned or is undergoing decommissioning. In this report, a preliminary evaluation of removing used nuclear fuel from 12 shutdown sites was conducted. The shutdown sites were Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. These sites have no other operating nuclear power reactors at their sites and have also notified the U.S. Nuclear Regulatory Commission that their reactors have permanently ceased power operations and that nuclear fuel has been permanently removed from their reactor vessels. Shutdown reactors at sites having other operating reactors are not included in this evaluation.

  1. Preliminary evaluation of the /sup 235/U(n,f) cross-section from 100 keV to 20 MeV

    SciTech Connect

    Bhat, M.R.

    1983-01-01

    A preliminary evaluation of the fission cross-section of /sup 235/U from 100 keV to 20 MeV is described. Variance-covariance matrices for a number of experimental data sets were constructed and used to evaluate the fission cross-section following a Bayesian procedure. The evaluated fission cross-section is compared with experimental data including the /sup 252/Cf fission neutron spectrum averages and some of the problems encountered in carrying out the fit are discussed.

  2. Crystallization and preliminary neutron diffraction experiment of human farnesyl pyrophosphate synthase complexed with risedronate.

    PubMed

    Yokoyama, Takeshi; Ostermann, Andreas; Mizuguchi, Mineyuki; Niimura, Nobuo; Schrader, Tobias E; Tanaka, Ichiro

    2014-04-01

    Nitrogen-containing bisphosphonates (N-BPs), such as risedronate and zoledronate, are currently used as a clinical drug for bone-resorption diseases and are potent inhibitors of farnesyl pyrophosphate synthase (FPPS). X-ray crystallographic analyses of FPPS with N-BPs have revealed that N-BPs bind to FPPS with three magnesium ions and several water molecules. To understand the structural characteristics of N-BPs bound to FPPS, including H atoms and hydration by water, neutron diffraction studies were initiated using BIODIFF at the Heinz Maier-Leibnitz Zentrum (MLZ). FPPS-risedronate complex crystals of approximate dimensions 2.8 × 2.5 × 1.5 mm (∼3.5 mm(3)) were obtained by repeated macro-seeding. Monochromatic neutron diffraction data were collected to 2.4 Å resolution with 98.4% overall completeness. Here, the first successful neutron data collection from FPPS in complex with N-BPs is reported.

  3. Crystallization of porcine pancreatic elastase and a preliminary neutron diffraction experiment

    SciTech Connect

    Kinoshita, Takayoshi; Tamada, Taro; Imai, Keisuke; Kurihara, Kazuo; Ohhara, Takashi; Tada, Toshiji; Kuroki, Ryota

    2007-04-01

    To investigate the structural characteristics of a covalent inhibitor bound to porcine pancreatic elastase (PPE), including H atoms and hydration by water, a crystal of porcine pancreatic elastase with its inhibitor was grown to a size of 1.6 mm{sup 3} for neutron diffraction study. The crystal diffracted to 2.3 Å resolution with sufficient quality for further structure determination owing to the similar atomic scattering properties of deuterium and carbon. Porcine pancreatic elastase (PPE) resembles the attractive drug target leukocyte elastase, which has been implicated in a number of inflammatory disorders. In order to investigate the structural characteristics of a covalent inhibitor bound to PPE, including H atoms and the hydration by water, a single crystal of PPE for neutron diffraction study was grown in D{sub 2}O containing 0.2 M sodium sulfate (pD 5.0) using the sitting-drop vapour-diffusion method. The crystal was grown to a size of 1.6 mm{sup 3} by repeated macroseeding. Neutron diffraction data were collected at room temperature using a BIX-3 diffractometer at the JRR-3 research reactor of the Japan Atomic Energy Agency (JAEA). The data set was integrated and scaled to 2.3 Å resolution in space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 51.2, b = 57.8, c = 75.6 Å.

  4. Preliminary evaluation of a lake whitefish (Coregonus clupeaformis) bioenergetics model

    USGS Publications Warehouse

    Madenjian, Charles P.; Pothoven, Steven A.; Schneeberger, Philip J.; O'Connor, Daniel V.; Brandt, Stephen B.

    2005-01-01

    We conducted a preliminary evaluation of a lake whitefish (Coregonus clupeaformis) bioenergetics model by applying the model to size-at-age data for lake whitefish from northern Lake Michigan. We then compared estimates of gross growth efficiency (GGE) from our bioenergetis model with previously published estimates of GGE for bloater (C. hoyi) in Lake Michigan and for lake whitefish in Quebec. According to our model, the GGE of Lake Michigan lake whitefish decreased from 0.075 to 0.02 as age increased from 2 to 5 years. In contrast, the GGE of lake whitefish in Quebec inland waters decreased from 0.12 to 0.05 for the same ages. When our swimming-speed submodel was replaced with a submodel that had been used for lake trout (Salvelinus namaycush) in Lake Michigan and an observed predator energy density for Lake Michigan lake whitefish was employed, our model predicted that the GGE of Lake Michigan lake whitefish decreased from 0.12 to 0.04 as age increased from 2 to 5 years.

  5. Preliminary Evaluation of Polyarylate Dielectric Films for Cryogenic Applications

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Fialla, Peter

    2002-01-01

    Polymeric materials are used extensively on spacecraft and satellites in electrical power and distribution systems, as thermal blankets and optical surface coatings, as well as mechanical support structures. The reliability of these systems when exposed to the harsh environment of space is very critical to the success of the mission and the safety of the crew in manned-flight ventures. In this work, polyarylate films were evaluated for potential use as capacitor dielectrics and wiring insulation for cryogenic applications. Two grades of the film were characterized in terms of their electrical and mechanical properties before and after exposure to liquid nitrogen (-196 C). The electrical characterization consisted of capacitance and dielectric loss measure Cents in the frequency range of 50 Hz to 100 kHz, and volume and surface resistivities. The mechanical measurements performed included changes in tensile (Young's modulus, elongation-at-break, and tensile strength) and structural properties (dimensional change, weight, and surface morphology). The preliminary results, which indicate good stability of the polymer after exposure to liquid nitrogen, are presented and discussed.

  6. Preliminary Design and Evaluation of Portable Electronic Flight Progress Strips

    NASA Technical Reports Server (NTRS)

    Doble, Nathan A.; Hansman, R. John

    2002-01-01

    There has been growing interest in using electronic alternatives to the paper Flight Progress Strip (FPS) for air traffic control. However, most research has been centered on radar-based control environments, and has not considered the unique operational needs of the airport air traffic control tower. Based on an analysis of the human factors issues for control tower Decision Support Tool (DST) interfaces, a requirement has been identified for an interaction mechanism which replicates the advantages of the paper FPS (e.g., head-up operation, portability) but also enables input and output with DSTs. An approach has been developed which uses a Portable Electronic FPS that has attributes of both a paper strip and an electronic strip. The prototype flight strip system uses Personal Digital Assistants (PDAs) to replace individual paper strips in addition to a central management interface which is displayed on a desktop computer. Each PDA is connected to the management interface via a wireless local area network. The Portable Electronic FPSs replicate the core functionality of paper flight strips and have additional features which provide a heads-up interface to a DST. A departure DST is used as a motivating example. The central management interface is used for aircraft scheduling and sequencing and provides an overview of airport departure operations. This paper will present the design of the Portable Electronic FPS system as well as preliminary evaluation results.

  7. Ultrasonic Evaluation of Deeply Located Trabecular Bones - Preliminary Results

    NASA Astrophysics Data System (ADS)

    Cieślik, Lucyna; Litniewski, Jerzy

    The analysis of ultrasonic signals scattered by soft tissues have been successfully applied for their characterization. Similarly, the trabecular bone backscattered signal contains information about the properties of the bone structure. Therefore scattering-based ultrasonic technique potentially enables the assessment of microstructure characteristics of a bone. The femoral neck fracture often occurs in the course of osteoporosis and can lead to severe complications. Therefore assessment of femoral bone microstructure and condition is important and essential for the diagnosis and treatment monitoring. As far most of the trabecular bone investigations have been performed in vitro. The only in vivo measurements were carried out in transmission and mostly concerned estimation of the attenuation in heel bone. We have built the ultrasonic scanner that could be useful in acquiring the RF (Radio Frequency) echoes backscattered by the trabecular bone in vivo. Moreover, the bone scanner provides data not only from heel bone but from deeply located bones as well (e.g. femoral bone). It can be also used for easily accessible bones like heel bone or breastbone. In this case a gel-pad is applied to assure focusing of ultrasound in trabecular bone (approximately 10 mm beneath the cortical bone). This study presents preliminary results of the attenuating properties evaluation of trabecular bone from the ultrasonic echoes backscattered by heel bone and femoral neck.

  8. Preliminary systems engineering evaluations for the National Ecological Observatory Network.

    SciTech Connect

    Robertson, Perry J.; Kottenstette, Richard Joseph; Crouch, Shannon M.; Brocato, Robert Wesley; Zak, Bernard Daniel; Osborn, Thor D.; Ivey, Mark D.; Gass, Karl Leslie; Heller, Edwin J.; Dishman, James Larry; Schubert, William Kent; Zirzow, Jeffrey A.

    2008-11-01

    The National Ecological Observatory Network (NEON) is an ambitious National Science Foundation sponsored project intended to accumulate and disseminate ecologically informative sensor data from sites among 20 distinct biomes found within the United States and Puerto Rico over a period of at least 30 years. These data are expected to provide valuable insights into the ecological impacts of climate change, land-use change, and invasive species in these various biomes, and thereby provide a scientific foundation for the decisions of future national, regional, and local policy makers. NEON's objectives are of substantial national and international importance, yet they must be achieved with limited resources. Sandia National Laboratories was therefore contracted to examine four areas of significant systems engineering concern; specifically, alternatives to commercial electrical utility power for remote operations, approaches to data acquisition and local data handling, protocols for secure long-distance data transmission, and processes and procedures for the introduction of new instruments and continuous improvement of the sensor network. The results of these preliminary systems engineering evaluations are presented, with a series of recommendations intended to optimize the efficiency and probability of long-term success for the NEON enterprise.

  9. Preliminary Neutronics Analysis of the ITER Toroidal Interferometer and Polarimeter Diagnostic Corner Cube Retroreflectors

    SciTech Connect

    Tresemer, K. R.

    2015-07-01

    ITER is an international project under construction in France that will demonstrate nuclear fusion at a power plant-relevant scale. The Toroidal Interferometer and Polarimeter (TIP) Diagnostic will be used to measure the plasma electron line density along 5 laser-beam chords. This line-averaged density measurement will be input to the ITER feedback-control system. The TIP is considered the primary diagnostic for these measurements, which are needed for basic ITER machine control. Therefore, system reliability & accuracy is a critical element in TIP’s design. There are two major challenges to the reliability of the TIP system. First is the survivability and performance of in-vessel optics and second is maintaining optical alignment over long optical paths and large vessel movements. Both of these issues greatly depend on minimizing the overall distortion due to neutron & gamma heating of the Corner Cube Retroreflectors (CCRs). These are small optical mirrors embedded in five first wall locations around the vacuum vessel, corresponding to certain plasma tangency radii. During the development of the design and location of these CCRs, several iterations of neutronics analyses were performed to determine and minimize the total distortion due to nuclear heating of the CCRs. The CCR corresponding to TIP Channel 2 was chosen for analysis as a good middle-road case, being an average distance from the plasma (of the five channels) and having moderate neutron shielding from its blanket shield housing. Results show that Channel 2 meets the requirements of the TIP Diagnostic, but barely. These results suggest other CCRs might be at risk of exceeding thermal deformation due to nuclear heating.

  10. Preliminary physicochemical evaluation of Kushta tutia: A Unani Formulation

    PubMed Central

    Tariq, Mohd; Chaudhary, Shahid Shah; Imtiyaz, Shaikh; Rahman, Khaleequr; Zaman, Roohi

    2014-01-01

    Background: Kushta is an important solid dosage form of Unani system of medicine used to treat various ailments. Very small particle size of kushta is responsible for its rapid absorption in body leading to instant therapeutic actions. Kushta tutia (KT) is one such renowned formulation used by hakims for successful management of various disorders. However, there is lack of scientific work on KT. Objectives: The present study was performed to evaluate KT physicochemically by testifying it on classical tests along with modern scientific techniques. Materials and Methods: Tutia was first detoxified as per classical literature. It was triturated with water and dried, afterwards subjected to calcination in furnace rather than cow dung cakes due to isolation of material being heated and better temperature control. Finished product was evaluated for physicochemical characteristics including preliminary tests mentioned in classical literature. Results: Floating and finger test were positive. Curd test showed no discoloration after 48 h. These findings indicate correct preparation of KT according to classical literature. Bulk density (0.96 ± 0.00 g/ml); tapped density (1.53 ± 0.00 g/ml); Hausner ratio (0.62 ± 0.00), compressibility index (37.52 ± 0.19%); loss of weight on drying (0.08 ± 0.00%); pH of 1 and 10% (5.20 ± 0.00) and 5.62 ± 0.00, respectively); total ash, acid insoluble ash, and water soluble ash values 95.75 ± 0.09, 6.57 ± 0.02, and 45.02 ± 0.20%, respectively; and extractive values 0.85 ± 0.02% were reported in KT. Conclusion: Since this work has not been reported earlier, the results obtained could be considered as the standard for KT for future studies. PMID:25336845

  11. Preliminary results of fast neutron treatments in carcinoma of the pancreas

    NASA Technical Reports Server (NTRS)

    Gahbauer, R.; Koh, K. Y.; Rodriguez-Antunez, A.; Jelden, G. L.; Turco, R. F.; Horton, J.; Bukowski, R.; Reimer, R.; Blue, J.; Roberts, W.

    1980-01-01

    A group of 30 patients with adenocarcinoma of the pancreas including some patients with very advanced disease, were treated with the so-called mixed beam modality employing photon treatments three times per week and neutron treatments twice a week. Two hundred Rads or equivalent Rads (RBE 3.3) were given in daily fractions aiming at a total dose of 6000 Rads in 6 to 8 weeks. The treatments were well tolerated and significant palliation was achieved in 26 to 30 cases. Twelve months survival was 33 percent with a median survival of 7 months or 210 days. Treatment techniques and localization procedures are discussed.

  12. Evaluation of absorbed dose in Gadolinium neutron capture therapy

    NASA Astrophysics Data System (ADS)

    Abdullaeva, Gayane; Djuraeva, Gulnara; Kim, Andrey; Koblik, Yuriy; Kulabdullaev, Gairatulla; Rakhmonov, Turdimukhammad; Saytjanov, Shavkat

    2015-02-01

    Gadolinium neutron capture therapy (GdNCT) is used for treatment of radioresistant malignant tumors. The absorbed dose in GdNCT can be divided into four primary dose components: thermal neutron, fast neutron, photon and natural gadolinium doses. The most significant is the dose created by natural gadolinium. The amount of gadolinium at the irradiated region is changeable and depends on the gadolinium delivery agent and on the structure of the location where the agent is injected. To de- fine the time dependence of the gadolinium concentration ρ(t) in the irradiated region the pharmacokinetics of gadolinium delivery agent (Magnevist) was studied at intratumoral injection in mice and intramuscular injection in rats. A polynomial approximation was applied to the experimental data and the influence of ρ(t) on the relative change of the absorbed dose of gadolinium was studied.

  13. Homogeneous immunoconjugates for boron neutron-capture therapy: design, synthesis, and preliminary characterization.

    PubMed

    Guan, L; Wims, L A; Kane, R R; Smuckler, M B; Morrison, S L; Hawthorne, M F

    1998-10-27

    The application of immunoprotein-based targeting strategies to the boron neutron-capture therapy of cancer poses an exceptional challenge, because viable boron neutron-capture therapy by this method will require the efficient delivery of 10(3) boron-10 atoms by each antigen-binding protein. Our recent investigations in this area have been focused on the development of efficient methods for the assembly of homogeneous immunoprotein conjugates containing the requisite boron load. In this regard, engineered immunoproteins fitted with unique, exposed cysteine residues provide attractive vehicles for site-specific modification. Additionally, homogeneous oligomeric boron-rich phosphodiesters (oligophosphates) have been identified as promising conjugation reagents. The coupling of two such boron-rich oligophosphates to sulfhydryls introduced to the CH2 domain of a chimeric IgG3 has been demonstrated. The resulting boron-rich immunoconjugates are formed efficiently, are readily purified, and have promising in vitro and in vivo characteristics. Encouragingly, these studies showed subtle differences in the properties of the conjugates derived from the two oligophosphate molecules studied, providing a basis for the application of rational design to future work. Such subtle details would not have been as readily discernible in heterogeneous conjugates, thus validating the rigorous experimental design employed here.

  14. Homogeneous immunoconjugates for boron neutron-capture therapy: Design, synthesis, and preliminary characterization

    PubMed Central

    Guan, Lufeng; Wims, Letitia A.; Kane, Robert R.; Smuckler, Mark B.; Morrison, Sherie L.; Hawthorne, M. Frederick

    1998-01-01

    The application of immunoprotein-based targeting strategies to the boron neutron-capture therapy of cancer poses an exceptional challenge, because viable boron neutron-capture therapy by this method will require the efficient delivery of 103 boron-10 atoms by each antigen-binding protein. Our recent investigations in this area have been focused on the development of efficient methods for the assembly of homogeneous immunoprotein conjugates containing the requisite boron load. In this regard, engineered immunoproteins fitted with unique, exposed cysteine residues provide attractive vehicles for site-specific modification. Additionally, homogeneous oligomeric boron-rich phosphodiesters (oligophosphates) have been identified as promising conjugation reagents. The coupling of two such boron-rich oligophosphates to sulfhydryls introduced to the CH2 domain of a chimeric IgG3 has been demonstrated. The resulting boron-rich immunoconjugates are formed efficiently, are readily purified, and have promising in vitro and in vivo characteristics. Encouragingly, these studies showed subtle differences in the properties of the conjugates derived from the two oligophosphate molecules studied, providing a basis for the application of rational design to future work. Such subtle details would not have been as readily discernible in heterogeneous conjugates, thus validating the rigorous experimental design employed here. PMID:9789066

  15. Preliminary Neutronics Design and Analysis of D2O Cooled High Conversion PWRs

    SciTech Connect

    Hikaru Hiruta; Gilles Youinou

    2012-09-01

    This report presents a neutronics analysis of tight-pitch D2O-cooled PWRs loaded with MOX fuel and focuses essentially on the Pu breeding potential of such reactors as well as on an important safety parameter, the void coefficient, which has to be negative. It is well known that fast reactors have a better neutron economy and are better suited than thermal reactors to breed fissile material from neutron capture in fertile material. Such fast reactors (e.g. sodium-cooled reactors) usually rely on technologies that are very different from those of existing water-cooled reactors and are probably more expensive. This report investigates another possibility to obtain a fast neutron reactor while still relying mostly on a PWR technology by: (1) Tightening the lattice pitch to reduce the water-to-fuel volume ratio compared to that of a standard PWR. Water-to-fuel volume ratios of between 0.45 and 1 have been considered in this study while a value of about 2 is typical of standard PWRs, (2) Using D2O instead of H2O as a coolant. Indeed, because of its different neutron physics properties, the use of D2O hardens the neutron spectrum to an extent impossible with H2O when used in a tight-pitch lattice. The neutron spectra thus obtained are not as fast as those in sodium-cooled reactor but they can still be characterized as fast compared to that of standard PWR neutron spectra. In the phase space investigated in this study we did not find any configurations that would have, at the same time, a positive Pu mass balance (more Pu at the end than at the beginning of the irradiation) and a negative void coefficient. At this stage, the use of radial blankets has only been briefly addressed whereas the impact of axial blankets has been well defined. For example, with a D2O-to-fuel volume ratio of 0.45 and a core driver height of about 60 cm, the fissile Pu mass balance between the fresh fuel and the irradiated fuel (50 GWd/t) would be about -7.5% (i.e. there are 7.5% fewer fissile Pu

  16. Neutron nuclear data evaluation of actinide nuclei for CENDL-3.1

    NASA Astrophysics Data System (ADS)

    Chen, Guo-Chang; Cao, Wen-Tian; Yu, Bao-Sheng; Tang, Guo-You; Shi, Zhao-Min; Tao, Xi

    2012-09-01

    New evaluations for several actinide nuclei of the third version of Chinese Evaluated Nuclear Data Library for Neutron Reaction Data (CENDL-3.1) have been completed and released. The evaluation is for all neutron induced reactions with uranium, neptunium, plutonium and americium in the mass range A = 232-241, 236-239, 236-246 and 240-244, respectively, and cover the incident neutron energy up to 20 MeV. In the present evaluation, much more effort was devoted to improving the reliability of the evaluated nuclear data for available new measured data, especially scarce or absent experimental data. A general description for the evaluation of several actinides' data is presented.

  17. Preliminary Evaluation of Removing Used Nuclear Fuel from Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph E.; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul E.; Massaro, Lawrence M.; Jensen, Philip J.

    2014-10-01

    This report presents a preliminary evaluation of removing used nuclear fuel (UNF) from 12 shutdown nuclear power plant sites. At these shutdown sites the nuclear power reactors have been permanently shut down and the sites have been decommissioned or are undergoing decommissioning. The shutdown sites are Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, Zion, Crystal River, Kewaunee, and San Onofre. The evaluation was divided into four components: characterization of the UNF and greater-than-Class C low-level radioactive waste (GTCC waste) inventory; a description of the on-site infrastructure and conditions relevant to transportation of UNF and GTCC waste; an evaluation of the near-site transportation infrastructure and experience relevant to shipping transportation casks containing UNF and GTCC waste, including identification of gaps in information; and, an evaluation of the actions necessary to prepare for and remove UNF and GTCC waste. The primary sources for the inventory of UNF and GTCC waste are the U.S. Department of Energy (DOE) RW-859 used nuclear fuel inventory database, industry sources such as StoreFUEL and SpentFUEL, and government sources such as the U.S. Nuclear Regulatory Commission. The primary sources for information on the conditions of site and near-site transportation infrastructure and experience included observations and information collected during visits to the Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion sites; information provided by managers at the shutdown sites; Facility Interface Data Sheets compiled for DOE in 2005; Services Planning Documents prepared for DOE in 1993 and 1994; industry publications such as Radwaste Solutions; and Google Earth. State and Regional Group representatives, a Tribal representative, and a Federal Railroad Administration representative participated in six of the shutdown site

  18. Historical Evaluation of Film Badge Dosimetry Y-12 Plant: Part 2–Neutron Radiation ORAUT-OTIB-0045

    SciTech Connect

    Kerr GD, Frome EL, Watkins JP, Tankersley WG

    2009-12-14

    A summary of the major neutron sources involved in radiation exposures to Y-12 workers is presented in this TIB. Graphical methods are used to evaluate available neutron dose data from quarterly exposures to Y-12 workers and to determine how the data could be used to derive neutron-to-gamma dose ratios for dose reconstruction purposes. This TIB provides estimates of neutron-to-gamma dose ratios for specific departments and a default value for the neutron-to-gamma dose ratio based on the pooled neutron dose data for all Y-12 departments.

  19. Status and Preliminary Evaluation for Chinese Re-Analysis Datasets

    NASA Astrophysics Data System (ADS)

    bin, zhao; chunxiang, shi; tianbao, zhao; dong, si; jingwei, liu

    2016-04-01

    Based on operational T639L60 spectral model, combined with Hybird_GSI assimilation system by using meteorological observations including radiosondes, buoyes, satellites el al., a set of Chinese Re-Analysis (CRA) datasets is developing by Chinese National Meteorological Information Center (NMIC) of Chinese Meteorological Administration (CMA). The datasets are run at 30km (0.28°latitude / longitude) resolution which holds higher resolution than most of the existing reanalysis dataset. The reanalysis is done in an effort to enhance the accuracy of historical synoptic analysis and aid to find out detailed investigation of various weather and climate systems. The current status of reanalysis is in a stage of preliminary experimental analysis. One-year forecast data during Jun 2013 and May 2014 has been simulated and used in synoptic and climate evaluation. We first examine the model prediction ability with the new assimilation system, and find out that it represents significant improvement in Northern and Southern hemisphere, due to addition of new satellite data, compared with operational T639L60 model, the effect of upper-level prediction is improved obviously and overall prediction stability is enhanced. In climatological analysis, compared with ERA-40, NCEP/NCAR and NCEP/DOE reanalyses, the results show that surface temperature simulates a bit lower in land and higher over ocean, 850-hPa specific humidity reflects weakened anomaly and the zonal wind value anomaly is focus on equatorial tropics. Meanwhile, the reanalysis dataset shows good ability for various climate index, such as subtropical high index, ESMI (East-Asia subtropical Summer Monsoon Index) et al., especially for the Indian and western North Pacific monsoon index. Latter we will further improve the assimilation system and dynamical simulating performance, and obtain 40-years (1979-2018) reanalysis datasets. It will provide a more comprehensive analysis for synoptic and climate diagnosis.

  20. Preliminary evaluation of the hydrogeologic system in Owens Valley, California

    USGS Publications Warehouse

    Danskin, W.R.

    1988-01-01

    A preliminary, two-layer, steady-state, groundwater flow model was used to evaluate present data and hydrologic concepts of Owens Valley, California. Simulations of the groundwater system indicate that areas where water levels are most affected by changes in recharge and discharge are near toes of alluvial fans and along the edge of permeable volcanic deposits. Sensitivity analysis for each model parameter shows that steady state simulations are most sensitive to uncertainties in evapotranspiration rates. Tungsten Hills, Poverty Hills, and Alabama Hills were found to act as virtually impermeable barriers to groundwater flow. Accurate simulation of the groundwater system between Bishop and Lone Pine appears to be possible without simulating the groundwater system in Round Valley, near Owens Lake, or in aquifer materials more than 1,000 ft below land surface. Although vast amounts of geologic and hydrologic data have been collected for Owens Valley, many parts of the hydrogeologic system have not been defined with sufficient detail to answer present water management questions. Location and extent of geologic materials that impede the vertical movement of water are poorly documented. The likely range of aquifer characteristics, except vertical hydraulic conductivity, is well known, but spatial distribution of these characteristics is not well documented. A set of consistent water budgets is needed, including one for surface water, groundwater, and the entire valley. The largest component of previous water budgets (evapotranspiration) is largely unverified. More definitive estimates of local gains and losses for Owens River are needed. Although groundwater pumpage from each well is measured, the quantity of withdrawal from different zones of permeable material has not been defined. (USGS)

  1. A preliminary neutron crystallography on the trypsin-bovine pancreatic trypsin inhibitor complex

    NASA Astrophysics Data System (ADS)

    Kawamura, K.; Yamada, T.; Kurihara, K.; Tamada, T.; Kuroki, R.; Tanaka, I.; Takahashi, H.; Niimura, N.

    2010-11-01

    Trypsin is one of serine proteases. BPTI (Bovine Pancreatic Trypsin Inhibitor) is a protein inhibitor, which binds trypsin tightly and inhibits cleavage of peptide bonds. X-ray structure determination of trypsin-BPTI complex could make clear the overview of the active site. However, information of hydrogen atoms related to catalytic mechanism has not been satisfied. In this study, the trypsin-BPTI complex structure has been determined by neutron diffraction data at 2.0 Å resolution. Deuterium atoms of catalytic triad, hydration structures in the binding pocket of trypsin and hydrogen bonds were observed. We would like to discuss details of hydrogen bonds in the interface between trypsin and BPTI and the adjacent water molecules including hydrogen atoms involved in the enzymatic reaction.

  2. Evaluated Mean Values and Covariances for the Prompt Fission Neutron Spectrum of 239Pu induced by neutrons of 500 keV

    SciTech Connect

    Neudecker, Denise

    2014-07-10

    This document provides the numerical values of the evaluated prompt fission neutron spectrum for 239Pu induced by neutrons of 500 keV as well as relative uncertainties and correlations. This document also contains a short description how these data were obtained and shows plots comparing the evaluated results to experimental information as well as the corresponding ENDF/B-VII.1 evaluation.

  3. Measurement of leakage neutron spectra from graphite cylinders irradiated with D-T neutrons for validation of evaluated nuclear data.

    PubMed

    Luo, F; Han, R; Chen, Z; Nie, Y; Shi, F; Zhang, S; Lin, W; Ren, P; Tian, G; Sun, Q; Gou, B; Ruan, X; Ren, J; Ye, M

    2016-10-01

    A benchmark experiment for validation of graphite data evaluated from nuclear data libraries was conducted for 14MeV neutrons irradiated on graphite cylinder samples. The experiments were performed using the benchmark experimental facility at the China Institute of Atomic Energy (CIAE). The leakage neutron spectra from the surface of graphite (Φ13cm×20cm) at 60° and 120° and graphite (Φ13cm×2cm) at 60° were measured by the time-of-flight (TOF) method. The obtained results were compared with the measurements made by the Monte Carlo neutron transport code MCNP-4C with the ENDF/B-VII.1, CENDL-3.1 and JENDL-4.0 libraries. The results obtained from a 20cm-thick sample revealed that the calculation results with CENDL-3.1 and JENDL-4.0 libraries showed good agreements with the experiments conducted in the whole energy region. However, a large discrepancy of approximately 40% was observed below the 3MeV energy region with the ENDF/B-VII.1 library. For the 2cm-thick sample, the calculated results obtained from the abovementioned three libraries could not reproduce the experimental data in the energy range of 5-7MeV. The graphite data in CENDL-3.1 were verified for the first time and were proved to be reliable. PMID:27620063

  4. Measurement of leakage neutron spectra from graphite cylinders irradiated with D-T neutrons for validation of evaluated nuclear data.

    PubMed

    Luo, F; Han, R; Chen, Z; Nie, Y; Shi, F; Zhang, S; Lin, W; Ren, P; Tian, G; Sun, Q; Gou, B; Ruan, X; Ren, J; Ye, M

    2016-10-01

    A benchmark experiment for validation of graphite data evaluated from nuclear data libraries was conducted for 14MeV neutrons irradiated on graphite cylinder samples. The experiments were performed using the benchmark experimental facility at the China Institute of Atomic Energy (CIAE). The leakage neutron spectra from the surface of graphite (Φ13cm×20cm) at 60° and 120° and graphite (Φ13cm×2cm) at 60° were measured by the time-of-flight (TOF) method. The obtained results were compared with the measurements made by the Monte Carlo neutron transport code MCNP-4C with the ENDF/B-VII.1, CENDL-3.1 and JENDL-4.0 libraries. The results obtained from a 20cm-thick sample revealed that the calculation results with CENDL-3.1 and JENDL-4.0 libraries showed good agreements with the experiments conducted in the whole energy region. However, a large discrepancy of approximately 40% was observed below the 3MeV energy region with the ENDF/B-VII.1 library. For the 2cm-thick sample, the calculated results obtained from the abovementioned three libraries could not reproduce the experimental data in the energy range of 5-7MeV. The graphite data in CENDL-3.1 were verified for the first time and were proved to be reliable.

  5. PRELIMINARY RESULTS: EVALUATIONS OF THE ALTERNATIVE ASBESTOS CONTROL METHOD FOR BUILDING DEMOLITION

    EPA Science Inventory

    This presentation describes the preliminary results of the evaluations of the alternative asbestos control method for demolishing buildings containing asbestos, and are covered under the regulatory requirements of the Asbestos NESHAP. This abstract and presentation are based, at ...

  6. Preliminary fracture analysis of the core pressure boundary tube for the Advanced Neutron Source Research Reactor

    SciTech Connect

    Schulz, K.C.; Yahr, G.T.

    1995-08-01

    The outer core pressure boundary tube (CPBT) of the Advanced neutron Source (ANS) reactor being designed at Oak Ridge National Laboratory is currently specified as being composed of 6061-T6 aluminum. ASME Boiler and Pressure Vessel Code fracture analysis rules for nuclear components are based on the use of ferritic steels; the expressions, tables, charts and equations were all developed from tests and analyses conducted for ferritic steels. Because of the nature of the Code, design with thin aluminum requires analytical approaches that do not directly follow the Code. The intent of this report is to present a methodology comparable to the ASME Code for ensuring the prevention of nonductile fracture of the CPBT in the ANS reactor. 6061-T6 aluminum is known to be a relatively brittle material; the linear elastic fracture mechanics (LEFM) approach is utilized to determine allowable flaw sizes for the CPBT. A J-analysis following the procedure developed by the Electric Power Research Institute was conducted as a check; the results matched those for the LEFM analysis for the cases analyzed. Since 6061-T6 is known to embrittle when irradiated, the reduction in K{sub Q} due to irradiation is considered in the analysis. In anticipation of probable requirements regarding maximum allowable flaw size, a survey of nondestructive inspection capabilities is also presented. A discussion of probabilistic fracture mechanics approaches, principally Monte Carlo techniques, is included in this report as an introduction to what quantifying the probability of nonductile failure of the CPBT may entail.

  7. Measurement/Evaluation Techniques and Nuclear Data Associated with Fission of 239Pu by Fission Spectrum Neutrons

    SciTech Connect

    Baisden, P; Bauge, E; Ferguson, J; Gilliam, D; Granier, T; Jeanloz, R; McMillan, C; Robertson, D; Thompson, P; Verdon, C; Wilkerson, C; Young, P

    2010-03-16

    This Panel was chartered to review and assess new evaluations of work on fission product data, as well as the evaluation process used by the two U.S. nuclear weapons physics laboratories. The work focuses on fission product yields resulting from fission spectrum neutrons incident on plutonium, and includes data from measurements that had not been previously published as well as new or revised fission product cumulative yield data, and related quantities such as Q values and R values. This report documents the Panel's assessment of the work presented by Los Alamos National Laboratory (LANL) and Lawrence Livermore National Laboratory (LLNL). Based on the work presented we have seven key observations: (1) Experiments conducted in the 1970s at LANL, some of which were performed in association with a larger, NIST-led, program, have recently been documented. A preliminary assessment of this work, which will be referred to in this document as ILRR-LANL, shows it to be technically sound. (2) LLNL has done a thorough, unbiased review and evaluation of the available literature and is in the process of incorporating the previously unavailable LANL data into its evaluation of key fission product yields. The results of the LLNL effort, which includes a preliminary evaluation of the ILRR-LANL data, have been documented. (3) LANL has also conducted an evaluation of fission product yields for fission spectrum neutrons on plutonium including a meta-analysis of benchmark data as part of a planned upgrade to the ENDF/B compilation. We found that the approach of using meta-analysis provides valuable additional insight for evaluating the sparse data sets involved in this assessment. (4) Both laboratories have provided convincing evidence for energy dependence in the fission product yield of {sup 147}Nd produced from the bombardment of {sup 239}Pu with fission spectrum neutrons over an incident neutron energy range of 0.2 to 1.9 MeV. (5) Consistent, complete, and explicit treatment of

  8. Resonance analysis and evaluation of the sup 235 U neutron induced cross sections

    SciTech Connect

    Leal, L.C.

    1990-06-01

    Neutron cross sections of fissile nuclei are of considerable interest for the understanding of parameters such as resonance absorption, resonance escape probability, resonance self-shielding,and the dependence of the reactivity on temperature. In the present study, new techniques for the evaluation of the {sup 235}U neutron cross sections are described. The Reich-Moore formalism of the Bayesian computer code SAMMY was used to perform consistent R-matrix multilevel analyses of the selected neutron cross-section data. The {Delta}{sub 3}-statistics of Dyson and Mehta, along with high-resolution data and the spin-separated fission cross-section data, have provided the possibility of developing a new methodology for the analysis and evaluation of neutron-nucleus cross sections. The results of the analysis consists of a set of resonance parameters which describe the {sup 235}U neutron cross sections up to 500 eV. The set of resonance parameters obtained through a R-matrix analysis are expected to satisfy statistical properties which lead to information on the nuclear structure. The resonance parameters were tested and showed good agreement with the theory. It is expected that the parametrization of the {sub 235}U neutron cross sections obtained in this dissertation represents the current state of art in data as well as in theory and, therefore, can be of direct use in reactor calculations. 44 refs., 21 figs., 8 tabs.

  9. A method for evaluating personal dosemeters in workplace with neutron fields.

    PubMed

    de Freitas Nascimento, Luana; Cauwels, Vanessa; Vanhavere, Filip

    2012-04-01

    Passive detectors, as albedo or track-etch, still dominate the field of neutron personal dosimetry, mainly due to their low-cost, high-reliability and elevated throughput. However, the recent appearance in the market of electronic personal dosemeters for neutrons presents a new option for personal dosimetry. In addition to passive detectors, electronic personal dosemeters necessitate correction factors, concerning their energy and angular response dependencies. This paper reports on the results of a method to evaluate personal dosemeters for workplace where neutrons are present. The approach here uses few instruments and does not necessitate a large mathematical workload. Qualitative information on the neutron energy spectrum is acquired using a simple spectrometer (Nprobe), reference values for H*(10) are derived from measurements with ambient detectors (Studsvik, Berthold and Harwell) and angular information is measured using personal dosemeters (electronic and bubbles dosemeters) disposed in different orientations on a slab phantom. PMID:21565843

  10. Data evaluation methods and improvements to the neutron-capture γ-ray spectrum

    NASA Astrophysics Data System (ADS)

    Hurst, A. M.; Firestone, R. B.; Summers, N. C.; Sleaford, B. W.; Revay, Zs.; Krtička, M.; Belgya, T.; Basunia, M. S.; Capote, R.; Choi, H.; Dashdorj, D.; Escher, J. E.; Nichols, A.; Szentmiklósi, L.

    2011-06-01

    Improved neutron-capture γ-ray spectra, not only of interest to the nuclear structure and reactions communities, are needed in a variety of applied and non-proliferation programs. This requires an evaluation of the existing experimental capture-γ data. Elemental neutron-capture data taken from direct measurements at the Budapest Reactor have been used to collate the Evaluated Gamma-ray Activation File, a database of capture γ-ray cross sections. These cross sections are then compared to Monte Carlo simulations of γ-ray emission following the thermal neutron-capture process using the statistical-decay code DICEBOX. The aim of this procedure is to obtain the total radiative neutron-capture cross section and confidently increase the number of levels and γ rays that can be assigned to a given isotope in the neutron data libraries. To achieve these goals and provide as complete information as possible in the neutron data libraries, it is also necessary to remain current with recent advances in nuclear structure physics and ensure that the latest data in the Evaluated Nuclear Structure Data File has been taken into consideration. This way an optimal level scheme can be derived by comparison with simulations and available experimental data. New information derived from this study can then be used to improve the nuclear structure and reactions databases with more-complete level schemes, and indeed, provide reliable and accurate input to a variety of applications which require this information. Recent results from neutron capture on the stable tungsten isotopes 182,183,184,186W are presented to illustrate the evaluation process.

  11. Fast Neutron Dose Evaluation Using CR39 by Coincidence Counting Process

    SciTech Connect

    Vilela, Eudice; Freitas, F. F. de; Brandao, J. O. C.; Santos, J. A. L.

    2008-08-07

    The solid state nuclear tracks detection (SSNTD) technique is widely used in the area of radiation dosimetry. Different materials can be used applying this technique as glass and the most used in the dosimetry field that are the polycarbonates, CR39 and Makrofol-DE. Both are very rich in hydrogenous, that enables the SSNTD to detect fast neutrons through recoils of protons in the own detector material, without need of converters. The low reproducibility of its backgroundhas often been the major drawback in the assessment of low fluences of fast neutrons with SSNTDs. This problem can be effectively solved by counting coincidence of tracks in two detectors foils irradiated in close contact. After processing and counting only tracks produced by the same recoil nuclei on the surfaces of both detectors are considered as a track. This procedure enables the reduction of the background counts in the response of the detectors. In this work a preliminary study on the application of the coincidence technique for neutron dosimetry is presented. The CR39 material was investigated aiming to achieve the personal dose equivalent for fast neutrons. Using this method of analysis a significant reduction on the lower detectable dose was observed resulting even one order of magnitude smaller value. Reading, however, needs to be automated due to the large areas necessary to achieve a satisfactory number of tracks for statistical significance of results.

  12. Uncertainty Quantification on Prompt Fission Neutrons Spectra

    SciTech Connect

    Talou, P. Madland, D.G.; Kawano, T.

    2008-12-15

    Uncertainties in the evaluated prompt fission neutrons spectra present in ENDF/B-VII.0 are assessed in the framework of the Los Alamos model. The methodology used to quantify the uncertainties on an evaluated spectrum is introduced. We also briefly review the Los Alamos model and single out the parameters that have the largest influence on the calculated results. Using a Kalman filter, experimental data and uncertainties are introduced to constrain model parameters, and construct an evaluated covariance matrix for the prompt neutrons spectrum. Preliminary results are shown in the case of neutron-induced fission of {sup 235}U from thermal up to 15 MeV incident energies.

  13. Preliminary evaluation of wind energy potential: Cook Inlet area, Alaska

    SciTech Connect

    Hiester, T.R.

    1980-06-01

    This report summarizes work on a project performed under contract to the Alaska Power Administration (APA). The objective of this research was to make a preliminary assessment of the wind energy potential for interconnection with the Cook Inlet area electric power transmission and distribution systems, to identify the most likely candidate regions (25 to 100 square miles each) for energy potential, and to recommend a monitoring program sufficient to quantify the potential.

  14. EVALUATION OF NEUTRON CROSS SECTIONS FOR A COMPLETE SET OF Nd ISOTOPES.

    SciTech Connect

    KIM,H.; HERMAN, M.; MUGHABGHAB, S.F.; OBLOZINSKY, P.; ROCHMAN, D.; LEE. Y.-O.

    2007-10-29

    Neutron cross sections for a complete set of Nd isotopes, {sup 142,143,144,145,146,147,148,150}Nd, were evaluated in the incident energy range from 10{sup -5} eV to 20 MeV. In the low energy region, including thermal and resolved resonances, our evaluations are based on the latest data published in the Atlas of Neutron Resonances. In the unresolved resonance region we performed additional evaluation by using the averages of the resolved resonances and adjusting them to the experimental data. In the fast neutron region, we used the nuclear reaction model code EMPIRE-2.19 validated against the experimental data. The results are compared to the existing nuclear data libraries, including ENDF/B-VI.8, JENDL-3.3 and JEFF-3.1, and to the available experimental data. The new evaluations are suitable for neutron transport calculations and they were adopted by the new evaluated nuclear data file of the United States, ENDF/B-VII.0, released in December 2006.

  15. An accelerator-based epithermal neutron beam design for BNCT and dosimetric evaluation using a voxel head phantom.

    PubMed

    Lee, Deok-jae; Han, Chi Young; Park, Sung Ho; Kim, Jong Kyung

    2004-01-01

    The beam shaping assembly design has been investigated in order to improve the epithermal neutron beam for accelerator-based boron neutron capture therapy in intensity and quality, and dosimetric evaluation for the beams has been performed using both mathematical and voxel head phantoms with MCNP runs. The neutron source was assumed to be produced from a conventional 2.5 MeV proton accelerator with a thick (7)Li target. The results indicate that it is possible to enhance epithermal neutron flux remarkably as well as to embody a good spectrum shaping to epithermal neutrons only with the proper combination of moderator and reflector. It is also found that a larger number of thermal neutrons can reach deeply into the brain and, therefore, can reduce considerably the treatment time for brain tumours. Consequently, the epithermal neutron beams designed in this study can treat more effectively deep-seated brain tumours.

  16. Preliminary evaluation of chemical flocculation in coal mine sediment ponds

    SciTech Connect

    Tapp, J.S.; Barfield, B.J.; Griffin, M.L.

    1980-12-01

    Laboratory and pilot scale studies were conducted in order to assess the effectiveness of various organic polyelectrolytes in enhancing the removal of total suspended solids in mine sediment ponds. Total suspended solids concentrations ranging from 2000 to 2000,000 mg/l were used. The results from both the laboratory and pilot scale studies showed that the polyelectrolytes were effective in enhancing suspended solids removal. The results from the laboratory studies showed that natural flocculation, particle aggregation, and the sweeping action of larger particles also played a role in the removal of suspended solids. Although only preliminary results for the pilot scale studies were presented, they strongly indicated that turbulence necessary to induce proper flocculation, particles also played a role in the removal of suspended solids. Although only preliminary results for the pilot scale studies were presented, they strongly indicated that turbulence necessary to induce proper flocculation, short circuiting and dead space are important parameters in determining the effectiveness of suspended solids removal in sediment ponds.

  17. Nuclear magnetic resonance evaluation of stroke: a preliminary report

    SciTech Connect

    Bryan, R.N.; Willcott, M.R.; Schneiders, N.J.; Ford, J.J.; Derman, H.S.

    1983-10-01

    Nine patients who had acute and subacute stroke were examined by nuclear magnetic resonance (NMR) using a 6-MHz Bruker Instruments proton scanner. A modified Carr-Purcell-Meiboom-Gill pulse sequence was used for signal detection. The resultant string of spin-echoes was Fourier transformed into projections that were subsequently back-projected to a series of spin-echo images. From these images, spin density and T/sub 2/ were calculated for each pixel. The NMR scans revealed stroke in each of the patients, while CT demonstrated only eight of the lesions. T/sub 2/ was prolonged in all of the ischemic regions and is the most sensitive NMR parameter in detecting stroke. These preliminary results suggest that NMR scanning of patients who have acute stroke may be cliniclly useful, and that the T/sub 2/ component of the NRM signal is most important.

  18. Fabrication and Preliminary Evaluation of Metal Matrix Microencapsulated Fuels

    SciTech Connect

    Terrani, Kurt A; Kiggans, Jim; Snead, Lance Lewis

    2012-01-01

    The metal matrix microencapsulated (M3) fuel concept for light water reactors (LWRs), consisting of coated fuel particles dispersed in a zirconium metal matrix, is introduced. Fabrication of M3 fuels by hot pressing, hot isostatic pressing, or extrusion methodologies has been demonstrated over the temperature range 800-1050 C. Various types of coated fuel particles with outermost layers of pyrocarbon, SiC, ZrC, and TiN have been incorporated into the zirconium metal matrix. Mechanical particle-particle and chemical particle-matrix interactions have been observed during the preliminary characterization of as-fabricated M3 specimens. Irradiation of three M3 rodlets with surrogate coated fuel particles was carried out at mean rod temperature of 400 C to 4.6 dpa in the zirconium metal matrix. Due to absence of texture in the metal matrix no irradiation growth strain (<0.09%) was detected during the post-irradiation examination.

  19. Preliminary evaluation of fiber composite reinforcement of truck frame rails

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.

    1977-01-01

    The use of graphite fiber/resin matrix composite to effectively reinforce a standard steel truck frame rail is studied. A preliminary design was made and it was determined that the reinforcement weight could be reduced by a factor of 10 when compared to a steel reinforcement. A section of a 1/3 scale reinforced rail was fabricated to demonstrate low cost manufacturing techniques. The scale rail section was then tested and increased stiffness was confirmed. No evidence of composite fatigue was found after 500,000 cycles to a fiber stress of 34,000 psi. The test specimen failed in bending in a static test at a load 50 percent greater than that predicted for a non-reinforced rail.

  20. EVALUATION OF TUNGSTEN ISOTOPES IN THE FAST NEUTRON RANGE INCLUDING CROSS-SECTION COVARIANCE ESTIMATION.

    SciTech Connect

    CAPOTE,R.; SIN, M.; TRKOV, A.; HERMAN, M.; CARLSON, B.V.; OBLOZINSKY, P.

    2007-04-22

    New evaluations for the tungsten isotopes {sup 180,182,183,184,186}W in the neutron energy range up to 60 MeV were produced. In the resonance range only minor adjustments to the resonance parameters were made due to a lack of adequate experimental data. Evaluations in the fast energy region were based on nuclear model calculations using the EMPIRE-2.19 code. Recently derived dispersive coupled-channel optical model potentials for W and Ta isotopes were instrumental to achieve a very good description of the available microscopic cross-section database. Model covariance data were generated with the Monte Carlo technique to produce a prior estimate for the covariance matrix. Experimental data were introduced through the GANDR system. The evaluated files were tested on selected fusion neutronics benchmarks and showed marked improvement compared to other existing evaluations.

  1. National Evaluation of the Weatherization Assistance Program: Preliminary Evaluation Plan for Program Year 2006

    SciTech Connect

    Ternes, Mark P; Schweitzer, Martin; Tonn, Bruce Edward; Schmoyer, Richard L; Eisenberg, Joel Fred

    2007-02-01

    . For example, the use of computerized audits has increased, cooling and baseload measures have been added, weatherization approaches tailored to the unique construction characteristics of mobile homes have been developed, the weatherization of large multifamily buildings has expanded and become more sophisticated, the flexibility to improve 'energy-related' health and safety has been provided, and leveraging with utilities, other state programs, and owners of large multifamily buildings has increased considerably. The Department of Energy tasked ORNL with planning the new evaluation in light of its experience in conducting the previous national evaluation and the metaevaluations. This preliminary evaluation plan, developed by ORNL, documents how the new national evaluation will be performed. In the remaining portion of this section, the purpose and fundamental questions the evaluation will address are identified and how these questions were derived is discussed.

  2. An Evaluation of Monte Carlo Simulations of Neutron Multiplicity Measurements of Plutonium Metal

    SciTech Connect

    Mattingly, John; Miller, Eric; Solomon, Clell J. Jr.; Dennis, Ben; Meldrum, Amy; Clarke, Shaun; Pozzi, Sara

    2012-06-21

    In January 2009, Sandia National Laboratories conducted neutron multiplicity measurements of a polyethylene-reflected plutonium metal sphere. Over the past 3 years, those experiments have been collaboratively analyzed using Monte Carlo simulations conducted by University of Michigan (UM), Los Alamos National Laboratory (LANL), Sandia National Laboratories (SNL), and North Carolina State University (NCSU). Monte Carlo simulations of the experiments consistently overpredict the mean and variance of the measured neutron multiplicity distribution. This paper presents a sensitivity study conducted to evaluate the potential sources of the observed errors. MCNPX-PoliMi simulations of plutonium neutron multiplicity measurements exhibited systematic over-prediction of the neutron multiplicity distribution. The over-prediction tended to increase with increasing multiplication. MCNPX-PoliMi had previously been validated against only very low multiplication benchmarks. We conducted sensitivity studies to try to identify the cause(s) of the simulation errors; we eliminated the potential causes we identified, except for Pu-239 {bar {nu}}. A very small change (-1.1%) in the Pu-239 {bar {nu}} dramatically improved the accuracy of the MCNPX-PoliMi simulation for all 6 measurements. This observation is consistent with the trend observed in the bias exhibited by the MCNPX-PoliMi simulations: a very small error in {bar {nu}} is 'magnified' by increasing multiplication. We applied a scalar adjustment to Pu-239 {bar {nu}} (independent of neutron energy); an adjustment that depends on energy is probably more appropriate.

  3. Evaluation of the neutron dosimeter used by Martin Marietta Energy Systems, Inc., ability to meet the requirements of the American National Standard for Personnel Neutron Dosimeters (neutron energies less than 20 MeV) ANSI N319-1976

    SciTech Connect

    Gunter, R.J.

    1994-07-01

    An evaluation of the neutron dosimeter used by the Centralized External Dosimetry System of Martin Marietta Energy Systems, Inc., was performed, and the dosimeter was shown to meet the requirements of the American National Standard for Personnel Neutron Dosimeters, ANSI N319-1976. This report details the requirements of the Standard, describes the tests performed, and evaluates the results of testing. To demonstrate compliance with the Standard, dosimeters were irradiated with a {sup 252}Cf source while mounted on a standard phantom. Dose was measured using the routine methodology employed by the Centralized External Dosimetry System for neutron dosimetry. The ability to accurately measure neutron dose was compared to specific performance criteria from the Standard. This includes testing the lower limit of detection, upper limit of detection, precision of results, and the capability to detect neutrons in a high gamma dose environment. In addition to neutron exposure, the dosimeters were required to be exposed to environmental factors including temperature extremes, high humidity, exposure to room light, and a drop to a hard surface. Only after exposure to these conditions were the dosimeters read, with results compared to the requirements of the Standard. Normal use factors of routine neutron dosimetry influencing the accuracy, sensitivity, or precision of the dosimetry system were also evaluated to measure their impact on dosimeter response.

  4. Measurement and evaluation of selected 14-MeV neutron cross sections for fusion

    SciTech Connect

    Meadows, J.W.; Smith, D.L.; Cox, S.A.

    1985-01-01

    Experimental neutron-activation cross-section data in the vicinity of 14 MeV are evaluated for several reactions of fusion-related interest using a least-squares method. New experimental measurements are performed at 14.7 MeV for all of these considered reactions and for some commonly-used standard reactions as well. Comparison is made between measured and evaluated results.

  5. Neutron scattering in Australia

    SciTech Connect

    Knott, R.B.

    1994-12-31

    Neutron scattering techniques have been part of the Australian scientific research community for the past three decades. The High Flux Australian Reactor (HIFAR) is a multi-use facility of modest performance that provides the only neutron source in the country suitable for neutron scattering. The limitations of HIFAR have been recognized and recently a Government initiated inquiry sought to evaluate the future needs of a neutron source. In essence, the inquiry suggested that a delay of several years would enable a number of key issues to be resolved, and therefore a more appropriate decision made. In the meantime, use of the present source is being optimized, and where necessary research is being undertaken at major overseas neutron facilities either on a formal or informal basis. Australia has, at present, a formal agreement with the Rutherford Appleton Laboratory (UK) for access to the spallation source ISIS. Various aspects of neutron scattering have been implemented on HIFAR, including investigations of the structure of biological relevant molecules. One aspect of these investigations will be presented. Preliminary results from a study of the interaction of the immunosuppressant drug, cyclosporin-A, with reconstituted membranes suggest that the hydrophobic drug interdigitated with lipid chains.

  6. Preliminary validation of computational model for neutron flux prediction of Thai Research Reactor (TRR-1/M1)

    NASA Astrophysics Data System (ADS)

    Sabaibang, S.; Lekchaum, S.; Tipayakul, C.

    2015-05-01

    This study is a part of an on-going work to develop a computational model of Thai Research Reactor (TRR-1/M1) which is capable of accurately predicting the neutron flux level and spectrum. The computational model was created by MCNPX program and the CT (Central Thimble) in-core irradiation facility was selected as the location for validation. The comparison was performed with the typical flux measurement method routinely practiced at TRR-1/M1, that is, the foil activation technique. In this technique, gold foil is irradiated for a certain period of time and the activity of the irradiated target is measured to derive the thermal neutron flux. Additionally, the flux measurement with SPND (self-powered neutron detector) was also performed for comparison. The thermal neutron flux from the MCNPX simulation was found to be 1.79×1013 neutron/cm2s while that from the foil activation measurement was 4.68×1013 neutron/cm2s. On the other hand, the thermal neutron flux from the measurement using SPND was 2.47×1013 neutron/cm2s. An assessment of the differences among the three methods was done. The difference of the MCNPX with the foil activation technique was found to be 67.8% and the difference of the MCNPX with the SPND was found to be 27.8%.

  7. Event-by-event evaluation of the prompt fission neutron spectrum from 239Pu(n,f)

    SciTech Connect

    Vogt, R; Randrup, J; Brown, D A; Descalle, M A; Ormand, W E

    2011-11-28

    We have developed an improved evaluation method for the spectrum of neutrons emitted in fission of {sup 239}Pu induced by incident neutrons with energies up to 20 MeV. The covariance data, including incident energy correlations introduced by the evaluation method, were used to fix the input parameters in our event-by-event model of fission, FREYA, by applying formal statistical methods. Formal estimates of uncertainties in the evaluation were developed by randomly sampling model inputs and calculating likelihood functions based on agreement with the evaluated . Our approach is able to employ a greater variety of fission measurements than the relatively coarse spectral data alone. It also allows the study of numerous fission observables for more accurate model validation. The combination of an event-by-event Monte Carlo fission model with a statistical-likelihood analysis is thus a powerful tool for evaluation of fission-neutron data. Our empirical model FREYA follows the complete fission event from birth of the excited fragments through their decay via neutron emission until the fragment excitation energy is below the neutron separation energy when neutron emission can no longer occur. The most recent version of FREYA incorporates pre-equilibrium neutron emission, the emission of the first neutron before equilibrium is reached in the compound nucleus, and multi-chance fission, neutron evaporation prior to fission when the incident neutron energy is above the neutron separation energy. Energy, momentum, charge and mass number are conserved throughout the fission process. The best available values of fragment masses and total kinetic energies are used as inputs to FREYA. We fit three parameters that are not well under control from previous measurements: the shift in the total fragment kinetic energy; the energy scale of the asymptotic level density parameter, controlling the fragment 'temperature' for neutron evaporation; and the relative excitation of the

  8. Preliminary Evaluation, Texas State Library Communication Network, 1968.

    ERIC Educational Resources Information Center

    Texas State Library, Austin. Field Services Div.

    In 1968 the Texas State Library established a library communications network under Title III of the Librar y Services and Construction Act. The objective of this study was to evaluate the network after six months of operation. Part I of the study consists of a general evaluation by Peat, Marwick, Mitchell and Co., based on operational data…

  9. Preliminary supersonic flight test evaluation of performance seeking control

    NASA Technical Reports Server (NTRS)

    Orme, John S.; Gilyard, Glenn B.

    1993-01-01

    Digital flight and engine control, powerful onboard computers, and sophisticated controls techniques may improve aircraft performance by maximizing fuel efficiency, maximizing thrust, and extending engine life. An adaptive performance seeking control system for optimizing the quasi-steady state performance of an F-15 aircraft was developed and flight tested. This system has three optimization modes: minimum fuel, maximum thrust, and minimum fan turbine inlet temperature. Tests of the minimum fuel and fan turbine inlet temperature modes were performed at a constant thrust. Supersonic single-engine flight tests of the three modes were conducted using varied after burning power settings. At supersonic conditions, the performance seeking control law optimizes the integrated airframe, inlet, and engine. At subsonic conditions, only the engine is optimized. Supersonic flight tests showed improvements in thrust of 9 percent, increases in fuel savings of 8 percent, and reductions of up to 85 deg R in turbine temperatures for all three modes. The supersonic performance seeking control structure is described and preliminary results of supersonic performance seeking control tests are given. These findings have implications for improving performance of civilian and military aircraft.

  10. Preliminary evaluation of DOE-NEPA monitoring system

    SciTech Connect

    Not Available

    1981-02-12

    The objective of this analysis was to perform a preliminary investigation of the problems involved in designing a Department of Energy-National Environmental Policy Act (DOE-NEPA) compliance monitoring system. The requirement for such a system arose from the Council on Environmental Quality (CEQ-NEPA regulation effective July 30, 1979. The CEQ regulation uses the term monitoring to denote any method by which the lead agency can assure implementation of Environmental Impact Statement (EIS) and Record of Decision (ROD) environmental mitigation commitments. Monitoring is required for mitigation measures in important cases and may be carried out at agency discretion for all other cases. No definition of important is given in the regulation. The NEPA intent is that all environmental information and planning be incorporated into the decision process as early as possible. In keeping with this concept, any monitoring or enforcement program for a mitigation measure is expected to be adopted and briefly and concisely described in the ROD. Information is presented in four chapters entitled: federal and state compliance monitoring surveys; EIS information analysis; enforcement mechanisms; and administrative practice.

  11. Evaluation of reconstruction errors and identification of artefacts for JET gamma and neutron tomography.

    PubMed

    Craciunescu, Teddy; Murari, Andrea; Kiptily, Vasily; Lupelli, Ivan; Fernandes, Ana; Sharapov, Sergei; Tiseanu, Ion; Zoita, Vasile

    2016-01-01

    The Joint European Torus (JET) neutron profile monitor ensures 2D coverage of the gamma and neutron emissive region that enables tomographic reconstruction. Due to the availability of only two projection angles and to the coarse sampling, tomographic inversion is a limited data set problem. Several techniques have been developed for tomographic reconstruction of the 2-D gamma and neutron emissivity on JET, but the problem of evaluating the errors associated with the reconstructed emissivity profile is still open. The reconstruction technique based on the maximum likelihood principle, that proved already to be a powerful tool for JET tomography, has been used to develop a method for the numerical evaluation of the statistical properties of the uncertainties in gamma and neutron emissivity reconstructions. The image covariance calculation takes into account the additional techniques introduced in the reconstruction process for tackling with the limited data set (projection resampling, smoothness regularization depending on magnetic field). The method has been validated by numerically simulations and applied to JET data. Different sources of artefacts that may significantly influence the quality of reconstructions and the accuracy of variance calculation have been identified.

  12. Neutronics and Fuel Performance Evaluation of Accident Tolerant Fuel under Normal Operation Conditions

    SciTech Connect

    Xu Wu; Piyush Sabharwall; Jason Hales

    2014-07-01

    This report details the analysis of neutronics and fuel performance analysis for enhanced accident tolerance fuel, with Monte Carlo reactor physics code Serpent and INL’s fuel performance code BISON, respectively. The purpose is to evaluate two of the most promising candidate materials, FeCrAl and Silicon Carbide (SiC), as the fuel cladding under normal operating conditions. Substantial neutron penalty is identified when FeCrAl is used as monolithic cladding for current oxide fuel. From the reactor physics standpoint, application of the FeCrAl alloy as coating layer on surface of zircaloy cladding is possible without increasing fuel enrichment. Meanwhile, SiC brings extra reactivity and the neutron penalty is of no concern. Application of either FeCrAl or SiC could be favorable from the fuel performance standpoint. Detailed comparison between monolithic cladding and hybrid cladding (cladding + coating) is discussed. Hybrid cladding is more practical based on the economics evaluation during the transition from current UO2/zircaloy to Accident Tolerant Fuel (ATF) system. However, a few issues remain to be resolved, such as the creep behavior of FeCrAl, coating spallation, inter diffusion with zirconium, etc. For SiC, its high thermal conductivity, excellent creep resistance, low thermal neutron absorption cross section, irradiation stability (minimal swelling) make it an excellent candidate materials for future nuclear fuel/cladding system.

  13. NEUTRON CROSS SECTION EVALUATIONS OF FISSION PRODUCTS BELOW THE FAST ENERGY REGION

    SciTech Connect

    OH,S.Y.; CHANG,J.; MUGHABGHAB,S.

    2000-05-11

    Neutron cross section evaluations of the fission-product isotopes, {sup 95}Mo, {sup 99}Tc, {sup 101}Ru, {sup 103}Rh, {sup 105}Pd, {sup 109}Ag, {sup 131}Xe, {sup 133}Cs, {sup 141}Pr, {sup 141}Nd, {sup 147}Sm, {sup 149}Sm, {sup 150}Sm, {sup 151}Sm, {sup 152}Sm, {sup 153}Eu, {sup 155}Gd, and {sup 157}Gd were carried out below the fast neutron energy region within the framework of the BNL-KAERI international collaboration. In the thermal energy region, the energy dependence of the various cross-sections was calculated by applying the multi-level Breit-Wigner formalism. In particular, the strong energy dependence of the coherent scattering lengths of {sup 155}Gd and {sup 157}Gd were determined and were compared with recent calculations of Lynn and Seeger. In the resonance region, the recommended resonance parameters, reported in the BNL compilation, were updated by considering resonance parameter information published in the literature since 1981. The s-wave and, if available, p-wave reduced neutron widths were analyzed in terms of the Porter-Thomas distribution to determine the average level spacings and the neutron strength functions. Average radiative widths were also calculated from measured values of resolved energy resonances. The average resonance parameters determined in this study were compared with those in the BNL and other compilations, as well as the ENDF/B-VI, JEF-2.2, and JENDL-3.2 data libraries. The unresolved capture cross sections of these isotopes, computed with the determined average resonance parameters, were compared with measurements, as well as the ENDF/B-VI evaluations. To achieve agreement with the measurements, in a few cases minor adjustments in the average resonance parameters were made. Because of astrophysical interest, the Maxwellian capture cross sections of these nuclides at a neutron temperature of 30 keV were computed and were compared with other compilations and evaluations.

  14. Preliminary ANS (Advanced Neutron Source) reactor cold source gain factor calculations for liquid deuterium and liquid nitrogen-15

    SciTech Connect

    Henderson, D.L.

    1988-11-01

    Individual energy group gain factors are computed for liquid nitrogen-15 and liquid deuterium cold source moderators using simple one-dimensional slab and spherical geometry calculational models. The energy spectrum of the neutron source is assumed to be that of a thermalized Maxwellian flux at 20/degree/C. The slab geometry calculations indicate that the optimum thickness for neutron transmission through a slab given an isotropic incident flux is for wavelengths above .6 nm, approximately .20 m for liquid deuterium and between .28 and .32 m for liquid nitrogen-15. The gain factors at .8 nm corresponding to these thicknesses are 15.5 for liquid deuterium and 3.50 for liquid nitrogen-15. The spherical geometry analysis showed that the cold neutron current below 10 MeV of 1.36 n/m/sup 2/-s for the neutron component entering the cavity of a .16 m thick liquid deuterium spherical shell exceeds the neutron leakage current of 1.08 n/cm/sup 2/-s from a .38 m diameter liquid deuterium solid sphere. However, the cold neutron factors for the neutron entering the void region are considerably lower than for the solid sphere case. 15 refs., 24 figs., 7 tabs.

  15. Super-Efficient Refrigerator Program (SERP) evaluation volume 2: Preliminary impact and market transformation assessment

    SciTech Connect

    Lee, A.D.; Conger, R.L.

    1996-08-01

    The Super Efficient Refrigerator Program (SERP) is a collaborative utility program intended to transform the market for energy-efficient and environmentally friendly refrigerators. It is one of the first examples of a large-scale {open_quotes}market transformation{close_quotes} energy efficiency program. This report documents the preliminary impact and market transformation evaluation of SERP ({open_quotes}the Program{close_quotes}). Pacific Northwest National Laboratory (PNNL) conducted this evaluation for the U.S. Department of Energy. This study focuses on the preliminary impact evaluation and market transformation assessment, but also presents limited process evaluation information. It is based on interviews with refrigerator dealers and manufacturers, interviews with utility participants, industry data, and information from the Program administrators. Results from this study complement those from prior process evaluation also conducted by PNNL. 42 refs., 5 figs., 4 tabs.

  16. Preliminary Technical and Legal Evaluation of Disposing of Nonhazardous Oil Field Waste into Salt Caverns

    SciTech Connect

    Ayers, Robert C.; Caudle, Dan; Elcock, Deborah; Raivel, Mary; Veil, John; and Grunewald, Ben

    1999-01-21

    This report presents an initial evaluation of the suitability, feasibility, and legality of using salt caverns for disposal of nonhazardous oil field wastes. Given the preliminary and general nature of this report, we recognize that some of our findings and conclusions maybe speculative and subject to change upon further research on this topic.

  17. Preliminary Evaluation of an Aviation Safety Thesaurus' Utility for Enhancing Automated Processing of Incident Reports

    NASA Technical Reports Server (NTRS)

    Barrientos, Francesca; Castle, Joseph; McIntosh, Dawn; Srivastava, Ashok

    2007-01-01

    This document presents a preliminary evaluation the utility of the FAA Safety Analytics Thesaurus (SAT) utility in enhancing automated document processing applications under development at NASA Ames Research Center (ARC). Current development efforts at ARC are described, including overviews of the statistical machine learning techniques that have been investigated. An analysis of opportunities for applying thesaurus knowledge to improving algorithm performance is then presented.

  18. Treating Preschool Children Who Stutter: Description and Preliminary Evaluation of a Family-Focused Treatment Approach

    ERIC Educational Resources Information Center

    Yaruss, Scott J.; Coleman, Craig; Hammer, David

    2006-01-01

    Purpose: The purpose of this article is to present a detailed description of a family-focused treatment for preschool children who stutter that addresses communication behaviors and attitudinal reactions that children and their parents may exhibit in reaction to stuttering, as well as a preliminary evaluation of the outcomes of that treatment.…

  19. Preliminary data for the 20 May 1974, simultaneous evaluation of remote sensors experiment. [water pollution monitoring

    NASA Technical Reports Server (NTRS)

    Johnson, R. W.; Batten, C. E.; Bowker, D. E.; Bressette, W. E.; Grew, G. W.

    1975-01-01

    Several remote sensors were simultaneously used to collect data over the tidal James River from Hopewell to Norfolk, Virginia. Sensors evaluated included the Multichannel-Ocean Color Sensor, multispectral scanners, and multispectral photography. Ground truth measurements and remotely sensed data are given. Preliminary analysis indicates that suspended sediment and concentrated industrial effluent are observable from all sensors.

  20. A Preliminary Evaluation of Fast ForWord-Language as an Adjuvant Treatment in Language Intervention

    ERIC Educational Resources Information Center

    Fey, Marc E.; Finestack, Lizbeth H.; Gajewski, Byron J.; Popescu, Mihai; Lewine, Jeffrey D.

    2010-01-01

    Purpose: Fast ForWord-Language (FFW-L) is designed to enhance children's processing of auditory-verbal signals and, thus, their ability to learn language. As a preliminary evaluation of this claim, we examined the effects of a 5-week course of FFW-L as an adjuvant treatment with a subsequent 5-week conventional narrative-based language…

  1. Description and Preliminary Training Evaluation of an Arc Welding Simulator. Research Report SRR 73-23.

    ERIC Educational Resources Information Center

    Abrams, Macy L.; And Others

    A prototype arc welding training simulator was designed to provide immediate, discriminative feedback and the capacity for concentrated practice. Two randomly selected groups of welding trainees were compared to evaluate the simulator, one group being trained using the simulator and the other using conventional practice. Preliminary data indicated…

  2. Preliminary ride-quality evaluation of the HM.2 Hoverferry

    NASA Technical Reports Server (NTRS)

    Mcclurken, E. W., Jr.; Jacobson, I. D.; Kuhlthau, A. R.

    1974-01-01

    The results of a forty-minute exposure of the HM.2 Hoverferry are presented. Quantitative evaluations were made from aft seats on the starboard side for a sea state considered calm and visually estimated at one-half to one foot. Since this type of craft is sensitive to sea state, the conclusions are based on ideal conditions. Some drawings are included.

  3. A Preliminary Examination of the In-Training Evaluation Report

    ERIC Educational Resources Information Center

    Skakun, Ernest N.; And Others

    1975-01-01

    The In-Training Evaluation Report (ITER), in use by the Royal College of Physicians and Surgeons of Canada for examining the competencies of candidates eligible for the certifying examination, was tested for validity and reliability. This analysis suggests revisions but declares the ITEA a useful instrument to aid in candidate assessment. (JT)

  4. Contextual E-Learning Evaluation: A Preliminary Framework

    ERIC Educational Resources Information Center

    Voigt, Christian; Swatman, Paula M. C.

    2004-01-01

    The evaluation of solutions is a major unresolved issue for all those involved in e-learning. In this paper we illustrate the importance of context by means of a qualitative comparison of two e-learning prototype implementations--an action research case undertaken in conjunction with a major German insurance company; and a more experimental…

  5. A method for fast evaluation of neutron spectra for BNCT based on in-phantom figure-of-merit calculation.

    PubMed

    Martín, Guido

    2003-03-01

    In this paper a fast method to evaluate neutron spectra for brain BNCT is developed. The method is based on an algorithm to calculate dose distribution in the brain, for which a data matrix has been taken into account, containing weighted biological doses per position per incident energy and the incident neutron spectrum to be evaluated. To build the matrix, using the MCNP 4C code, nearly monoenergetic neutrons were transported into a head model. The doses were scored and an energy-dependent function to biologically weight the doses was used. To find the beam quality, dose distribution along the beam centerline was calculated. A neutron importance function for this therapy to bilaterally treat deep-seated tumors was constructed in terms of neutron energy. Neutrons in the energy range of a few tens of kilo-electron-volts were found to produce the best dose gain, defined as dose to tumor divided by maximum dose to healthy tissue. Various neutron spectra were evaluated through this method. An accelerator-based neutron source was found to be more reliable for this therapy in terms of therapeutic gain than reactors.

  6. [Clinical diagnosis and standardized evaluation of borderline personality: preliminary report].

    PubMed

    Chaine, F; Guelfi, J D; Monier, C; Brun, A; Seunevel, F

    1995-01-01

    A sample of 36 patients considered by French clinicians as suffering from a borderline personality disorder was evaluated using the International Personality Disorder Examination, the Diagnostic Interview for Borderline-Revised, and the Minnesota Multiphasic Personality Inventory. First, global descriptive analysis of the sample elicited the socio-demographic and standard clinical characteristics of the borderline individuals. After diagnostic evaluation, the sample appeared to be quite homogeneous with 25 of the 36 patients evaluated (69.5%) being defined as borderline by two of the three diagnostic systems: ICD 10, DSM III-R and Gunderson (15/36 = 41.5% of patients were defined as borderline by all three systems). It is the types of BL personality co-diagnoses which differentiated the BL subjects in the sample from those classically described in the international literature, since the most frequent personalities were the Dependent and Avoiding ones, not the Antisocial, Histrionic, Narcissistic or Schizotypic personalities of the DSM III-R. ICD 10 elicited the same significant prevalence of Anxious and Dependent personalities. Lastly, the patients diagnosed as borderline both by clinicians and by all diagnostic systems (forming the sample "core") were compared with the rest of the sample with regard to socio-demographic, clinical and diagnostic characteristics. A few hypotheses are proposed on the type of variables that may permit to discriminate between these two types of patients.

  7. Evaluation of neutron background in cryogenic Germanium target for WIMP direct detection when using reactor neutrino detector as neutron veto

    NASA Astrophysics Data System (ADS)

    Xu, Ye; Lan, Jieqin; Bai, Ying; Gao, Weiwei

    2016-09-01

    A direct WIMP (Weakly Interacting Massive Particle) detector with a neutron veto system is designed to better reject neutrons. An experimental configuration is studied in the present paper: 984 Ge modules are placed inside a reactor neutrino detector. In order to discriminate between nuclear and electron recoil, both ionization and heat signatures are measured using cryogenic germanium detectors in this detection. The neutrino detector is used as a neutron veto device. The neutron background for the experimental design has been estimated using the Geant4 simulation. The results show that the neutron background can decrease to O(0.01) events per year per tonne of high purity Germanium. We calculate the sensitivity to spin-independent WIMP-nucleon elastic scattering. An exposure of one tonne × year could reach a cross-section of about 2×10-11 pb.

  8. Background evaluation for the neutron sources in the Daya Bay experiment

    NASA Astrophysics Data System (ADS)

    Gu, W. Q.; Cao, G. F.; Chen, X. H.; Ji, X. P.; Li, G. S.; Ling, J. J.; Liu, J.; Qian, X.; Wang, W.

    2016-10-01

    We present an evaluation of the background induced by 241Am-13C neutron calibration sources in the Daya Bay reactor neutrino experiment. As a significant background for electron-antineutrino detection at 0.26 ± 0.12 per detector per day on average, it has been estimated by a Monte Carlo simulation that was benchmarked by a special calibration data set. This dedicated data set also provides the energy spectrum of the background.

  9. A unified Monte Carlo approach to fast neutron cross section data evaluation.

    SciTech Connect

    Smith, D.; Nuclear Engineering Division

    2008-03-03

    A unified Monte Carlo (UMC) approach to fast neutron cross section data evaluation that incorporates both model-calculated and experimental information is described. The method is based on applications of Bayes Theorem and the Principle of Maximum Entropy as well as on fundamental definitions from probability theory. This report describes the formalism, discusses various practical considerations, and examines a few numerical examples in some detail.

  10. Evaluation of Silicon Neutron Resonance Parameters in the Energy Range Thermal to 1800 keV

    SciTech Connect

    Derrien, H.

    2002-09-30

    The evaluation of the neutron cross sections of the three stable isotopes of silicon in the energy range thermal to 20 MeV was performed by Hetrick et al. for ENDF/B-VI (Evaluated Nuclear Data File). Resonance parameters were obtained in the energy range thermal to 1500 keV from a SAMMY analysis of the Oak Ridge National Laboratory experimental neutron transmission data. A new measurement of the capture cross section of natural silicon in the energy range 1 to 700 keV has recently been performed at the Oak Ridge Electron Linear Accelerator. Results of this measurement were used in a SAMMY reevaluation of the resonance parameters, allowing determination of the capture width of a large number of resonances. The experimental data base is described; properties of the resonance parameters are given. For the first time the direct neutron capture component has been taken into account from the calculation by Rauscher et al. in the energy range from thermal to 1 MeV. Results of benchmark calculations are also given. The new evaluation is available in the ENDF/B-VI format.

  11. Preliminary field evaluation of high efficiency steel filters

    SciTech Connect

    Bergman, W.; Larsen, G.; Lopez, R.

    1995-02-01

    We have conducted an evaluation of two high efficiency steel filters in the exhaust of an uranium oxide grit blaster at the Y-12 Plant in Oak Ridge Tennessee. The filters were installed in a specially designed filter housing with a reverse air-pulse cleaning system for automatically cleaning the filters in-place. Previous tests conducted on the same filters and housing at LLNL under controlled conditions using Arizona road dust showed good cleanability with reverse air pulses. Two high efficiency steel filters, containing 64 pleated cartridge elements housed in the standard 2` x 2` x 1` HEPA frame, were evaluated in the filter test housing using a 1,000 cfm slip stream containing a high concentration of depleted uranium oxide dust. One filter had the pleated cartridges manufactured to our specifications by the Pall Corporation and the other by Memtec Corporation. Test results showed both filters had a rapid increase in pressure drop with time, and reverse air pulses could not decrease the pressure drop. We suspected moisture accumulation in the filters was the problem since there were heavy rains during the evaluations, and the pressure drop of the Memtec filter decreased dramatically after passing clean, dry air through the filter and after the filter sat idle for one week. Subsequent laboratory tests on a single filter cartridge confirmed that water accumulation in the filter was responsible for the increase in filter pressure drop and the inability to lower the pressure drop by reverse air pulses. No effort was made to identify the source of the water accumulation and correct the problem because the available funds were exhausted.

  12. Preliminary evaluation of a space AMTEC power conversion system

    NASA Technical Reports Server (NTRS)

    Crowley, Christopher J.; Sievers, Robert K.

    1991-01-01

    As original evaluation of a space solar energy source coupled with Alkali Metal Thermoelectric Conversion (AMTEC) is presented here. This study indicates that an AMTEC system would have 30 percent of the mass of a photovoltaic system and 70 percent of the mass of a Stirling cycle system at the 35-kWe level of power generation modules typical of the baseline for the U.S. Space Station. The operating temperatures and sodium heat pipe components for solar receiver/TES hardware (currently being developed by NASA) integrate well with AMTEC power conversion. AMTEC is therefore an attractive alternative specifically for space solar power generation.

  13. "Think the sink:" Preliminary evaluation of a handwashing promotion campaign.

    PubMed

    Mackert, Michael; Liang, Ming-Ching; Champlin, Sara

    2013-03-01

    Owing to its utility in guiding the planning and evaluation of health promotion campaigns, the Theory of Planned Behavior was used to implement a 1-month campaign aimed at increasing handwashing among college students. Based on observations of bathroom users' handwashing behavior (n = 1,005) and an online survey (n = 188), overall handwashing did not increase as a result of the campaign; however, more students did use soap (58% vs 70%). Future campaigns designed to increase handwashing behavior in students may be advised to target messages according to gender difference-based responsiveness to handwashing norms. PMID:22990299

  14. Preliminary flight evaluation of an engine performance optimization algorithm

    NASA Technical Reports Server (NTRS)

    Lambert, H. H.; Gilyard, G. B.; Chisholm, J. D.; Kerr, L. J.

    1991-01-01

    A performance seeking control (PSC) algorithm has undergone initial flight test evaluation in subsonic operation of a PW 1128 engined F-15. This algorithm is designed to optimize the quasi-steady performance of an engine for three primary modes: (1) minimum fuel consumption; (2) minimum fan turbine inlet temperature (FTIT); and (3) maximum thrust. The flight test results have verified a thrust specific fuel consumption reduction of 1 pct., up to 100 R decreases in FTIT, and increases of as much as 12 pct. in maximum thrust. PSC technology promises to be of value in next generation tactical and transport aircraft.

  15. Preliminary surface-emitting laser logic device evaluation

    NASA Astrophysics Data System (ADS)

    Libby, S. I.; Parker, M. A.; Olbright, G. R.; Swanson, P. D.

    1993-03-01

    This report discusses the evaluation of a monolithically integrated heterojunction phototransistor and vertical-cavity surface-emitting laser, designated the surface-Emitting Laser Logic device (CELL). Included is a discussion of the device structure and theory of operation, test procedures, results, and conclusions. Also presented is the CELL's opto-electronic input/output characteristics which includes spectral analysis, characteristic emitted light versus current and current versus voltage curves, input wavelength tolerance, output wavelength sensitivity to bias current, and insensitivity to input wavelength and power within a specified range.

  16. Preliminary evaluation of a space AMTEC power conversion system

    NASA Astrophysics Data System (ADS)

    Crowley, Christopher J.; Sievers, Robert K.

    As original evaluation of a space solar energy source coupled with Alkali Metal Thermoelectric Conversion (AMTEC) is presented here. This study indicates that an AMTEC system would have 30 percent of the mass of a photovoltaic system and 70 percent of the mass of a Stirling cycle system at the 35-kWe level of power generation modules typical of the baseline for the U.S. Space Station. The operating temperatures and sodium heat pipe components for solar receiver/TES hardware (currently being developed by NASA) integrate well with AMTEC power conversion. AMTEC is therefore an attractive alternative specifically for space solar power generation.

  17. Preliminary evaluation of a space AMTEC power conversion system

    NASA Astrophysics Data System (ADS)

    Crowley, Christopher J.; Sievers, Robert K.

    1991-01-01

    An original evaluation of a space solar energy source coupled with Alkali Metal Thermoelectric Conversion (AMTEC) is presented here. This study indicates that an AMTEC system would have 30 percent of the mass of a photovoltaic system and 70 percent of the mass of a Stirling cycle system at the 35-kWe level of power generation modules typical of the baseline for the U.S. Space Station. The operating temperatures and Sodium heat pipe components for solar receiver/TES hardware (currently being developed by NASA) integrate well with AMTEC power conversion. AMTEC is therefore an attractive alternative specifically for space solar power generation.

  18. World Opinion and the Soviet Satellite: A Preliminary Evaluation

    NASA Technical Reports Server (NTRS)

    1957-01-01

    Less than two weeks after the launch of Sputnik I, the United States Information Agency conducted an informal analysis of public opinion on this subject. The analysis yielded four clear conclusions: (1) Soviet claims of scientific and technological superiority were widely accepted in the United States; (2) U.S. allies were concerned about a shift in the balance of military power; (3) the overall credibility of Soviet propaganda was greatly strengthened; and (4) American prestige was dealt a severe blow. The report also concluded that the near-hysteria in the United States in turn increased the level of concern in countries friendly to the United States. An evaluation is presented.

  19. Preliminary evaluation of a proposed injection site in Mellones

    SciTech Connect

    Ortiz, N.V.; Rada, H.M.

    1996-08-01

    A hydrogeological evaluation was carried out in the Melones area to determine the feasibility of disposing brackish water and brines associated with oil production activities. The region is located towards north-central Hamaca, in the Anzoategui state, and covers an area of approximately 454 km{sup 2}. The study was based on the examination and interpretation of available stratigraphic and structural maps, well logs and formation water analysis. Engineering properties were estimated from 42 wells, selected from a total of 575 wells, where complete sets of well logs were available. The most suitable injection interval, integrated by the 02/3, D1-D2-D3-D4 and E1-E2 sands from the upper part of the Oficina Formation, was selected by addressing certain technical requirements for suitable potential disposal sites and injection intervals. A two-dimensional finite difference flow model was used to simulate the long-term hydraulic head buildup under projected operating conditions. After examination of the important characteristics considered in the evaluation process, it appears that the Melones area favorably meets most criteria.

  20. [Preliminary study on pharmacodynamic evaluation method of Houpo formula particles].

    PubMed

    Ma, Lu; Shao, Li-Jie; Tang, Fang

    2014-04-01

    To discuss the feasibility of the pharmacodynamic evaluation method for traditional Chinese medicine (TCM) formula particles, with traditional decoction for reference and the intervention of Magnoliae Officinalis Cortex in rats with ulcerative colitis (UC). First of all, the similarity of traditional Magnoliae Officinalis Cortex decoction and formula particles of different manufacturers was defined by using the IR fingerprint. The UC rat model was established and given Houpo formula particles of different doses and manufacturers, with the decoction for reference, in order to observe disease activity index (DAI), colon mucosa damage index (CMDI), pathologic changes, nitric oxide (NO), endothdin (ET), substance P, vasoactive intestinal peptide (VIP). Their intervention effects on UC rats were compared to study the difference between Sanjiu and Tianjiang Houpo formula particles, in order to demonstrate the feasibility of the pharmacodynamic evaluation method for Houpo formula particles. According to the results, Houpo formula particles showed similar pharmacodynamic actions with the traditional decoction. The pharmacodynamic comparison of Houpo formula particles of different manufacturers showed no statistical significance. The experiment showed that on the basis of the TCM compounds, a prescription dismantlement study was conducted to define target points of various drugs. The traditional decoction was selected for reference in the comparison of corresponding formula particles for their pharmacodynamic equivalence. This method could avoid controversies about single or combined boiling of formula particles, and give objective comments on the pharmacodynamic effect of the formula particles. The method is proved to be feasible. PMID:25039188

  1. SELECTION AND PRELIMINARY EVALUATION OF ALTERNATIVE REDUCTANTS FOR SRAT PROCESSING

    SciTech Connect

    Stone, M.; Pickenheim, B.; Peeler, D.

    2009-06-30

    Defense Waste Processing Facility - Engineering (DWPF-E) has requested the Savannah River National Laboratory (SRNL) to perform scoping evaluations of alternative flowsheets with the primary focus on alternatives to formic acid during Chemical Process Cell (CPC) processing. The reductants shown below were selected for testing during the evaluation of alternative reductants for Sludge Receipt and Adjustment Tank (SRAT) processing. The reductants fall into two general categories: reducing acids and non-acidic reducing agents. Reducing acids were selected as direct replacements for formic acid to reduce mercury in the SRAT, to acidify the sludge, and to balance the melter REDuction/OXidation potential (REDOX). Non-acidic reductants were selected as melter reductants and would not be able to reduce mercury in the SRAT. Sugar was not tested during this scoping evaluation as previous work has already been conducted on the use of sugar with DWPF feeds. Based on the testing performed, the only viable short-term path to mitigating hydrogen generation in the CPC is replacement of formic acid with a mixture of glycolic and formic acids. An experiment using glycolic acid blended with formic on an 80:20 molar basis was able to reduce mercury, while also targeting a predicted REDuction/OXidation (REDOX) of 0.2 expressed as Fe{sup 2+}/{Sigma}Fe. Based on this result, SRNL recommends performing a complete CPC demonstration of the glycolic/formic acid flowsheet followed by a design basis development and documentation. Of the options tested recently and in the past, nitric/glycolic/formic blended acids has the potential for near term implementation in the existing CPC equipment providing rapid throughput improvement. Use of a non-acidic reductant is recommended only if the processing constraints to remove mercury and acidify the sludge acidification are eliminated. The non-acidic reductants (e.g. sugar) will not reduce mercury during CPC processing and sludge acidification would

  2. Preliminary process engineering evaluation of ethanol production from vegetative crops

    NASA Astrophysics Data System (ADS)

    Moreira, A. R.; Linden, J. C.; Smith, D. H.; Villet, R. H.

    1982-12-01

    Vegetative crops show good potential as feedstock for ethanol production via cellulose hydrolysis and yeast fermentation. The low levels of lignin encountered in young plant tissues show an inverse relationship with the high cellulose digestibility during hydrolysis with cellulose enzymes. Ensiled sorghum species and brown midrib mutants of sorghum exhibit high glucose yields after enzyme hydrolysis as well. Vegetative crop materials as candidate feedstocks for ethanol manufacture should continue to be studied. The species studied so far are high value cash crops and result in relatively high costs for the final ethanol product. Unconventional crops, such as pigweed, kochia, and Russian thistle, which can use water efficiently and grow on relatively arid land under conditions not ideal for food production, should be carefully evaluated with regard to their cultivation requirements, photosynthesis rates, and cellulose digestibility. Such crops should result in more favorable process economics for alcohol production.

  3. Preliminary evaluation of the Illinois Residential Affordable Payment Program (IRAPP)

    SciTech Connect

    Reddy, A.B.; Griffin, B.S.; Lieberman, B.; Baker, D.

    1988-03-01

    The Illinois Residential Affordable Payment Program (IRAPP) was authorized by the Illinois Energy Assistance Act of 1985. IRAPP is an energy-assistance program for low-income households that have incomes of less than 125% of poverty level and receive utility services from a public utility. In return for percent of income payments, low-income households are guaranteed continuous natural gas and/or electricity utility service. The program was placed in operation in December 1985. The study reported here is an evaluation of this program. Program-eligible households were compared to determine: (1) what household characteristics lead to program participation; (2) what effects the program has on consumption of natural gas and electricity, utility-service disconnections, and low-income households' utility costs; and (3) how much the program cost per participant household.

  4. Preliminary resolved resonance region evaluation of copper-63 from 0 to 300 keV

    SciTech Connect

    Sobes, V.; Forget, B.; Leal, L.; Guber, K.

    2012-07-01

    A new preliminary evaluation of Cu-63 was done in the energy region from 0 to 300 keV extending the resolved resonance region of the previous, ENDF/B-VII.0, evaluation three-fold. The new evaluation was based on three experimental transmission data sets; two measured at the Oak Ridge Electron Linear Accelerator (ORELA) and one from the Massachusetts Inst. of Technology Nuclear Reactor (MITR). A total of 275 new resonances were identified and a corresponding set of external resonances was approximated to mock up the external levels. The negative external levels (bound level) were modified to match the thermal cross section values. A preliminary benchmarking calculation was made using 11 ICSBEP benchmarks. This work is in support of the DOE Nuclear Criticality Safety Program. (authors)

  5. Preliminary evaluation of robotic needle distal tip repositioning

    NASA Astrophysics Data System (ADS)

    Walsh, Conor J.; Slocum, Alexander H.; Gupta, Rajiv

    2011-03-01

    Advances in medical imaging now provide detailed images of solid tumors inside the body and miniaturized energy delivery systems enable tumor destruction through local heating powered by a thin electrode. We have developed a robot for accurately repositioning the distal tip of a medical instrument such an ablation probe to adjacent points within tissue. The position accuracy in ballistics gelatin was evaluated in a 2D experimental setup with a digital SLR camera that was fixed to a rig that also contained the gelatin. The robot was mounted to the rig in such a way that the stylet was deployed in a plane parallel the camera's lens. A grid paper attached to the back of the box containing the gelatin provided a stationary reference point for each of the pictures taken and also served as a coordinate system for making measurements. The measurement repeatability error was found by taking a stylet tip position measurement five times for two different pictures and found to be 0.26 mm. For a stylet with a radius of curvature of 31.5 mm and a diameter of 0.838 mm, the targeting accuracy was found to be 2.5 +/- 1.4 mm at points that were approximately 38 mm lateral from the cannula axis.

  6. Mortar radiocarbon dating: preliminary accuracy evaluation of a novel methodology.

    PubMed

    Marzaioli, Fabio; Lubritto, Carmine; Nonni, Sara; Passariello, Isabella; Capano, Manuela; Terrasi, Filippo

    2011-03-15

    Mortars represent a class of building and art materials that are widespread at archeological sites from the Neolithic period on. After about 50 years of experimentation, the possibility to evaluate their absolute chronology by means of radiocarbon ((14)C) remains still uncertain. With the use of a simplified mortar production process in the laboratory environment, this study shows the overall feasibility of a novel physical pretreatment for the isolation of the atmospheric (14)CO(2) (i.e., binder) signal absorbed by the mortars during their setting. This methodology is based on the assumption that an ultrasonic attack in liquid phase isolates a suspension of binder carbonates from bulk mortars. Isotopic ((13)C and (14)C), % C, X-ray diffractometry (XRD), and scanning electron microscopy (SEM) analyses were performed to characterize the proposed methodology. The applied protocol allows suppression of the fossil carbon (C) contamination originating from the incomplete burning of the limestone during the quick lime production, providing unbiased dating for "laboratory" mortars produced operating at historically adopted burning temperatures.

  7. A preliminary evaluation of the nonfuel mineral potential of Somalia

    USGS Publications Warehouse

    Greenwood, W.R.

    1982-01-01

    Additional exploration in Somalia is warranted for a wide variety of metallic and nonmetallic deposits. In Precambrian rocks, deposit types favorable for exploration include: a banded iron formation; platinum-bearing mafic-ultramafic complexes; tin-bearing quartz veins; phosphorite; stratabound base-metal deposits; uranium associated with Precambrian(?) syenite; apatite, molybdenum, and alumina in alkalic rocks; Jurassic and Cretaceous black shales; possible bedded-barite and massive base- and precious-metal sulfide deposits; vein barite in Tertiary rocks in fault zones; sepiolite and bentonite for drilling muds and other industrial uses; celestite; possible Tertiary zeolite; and uranium deposits. Several of these deposit types could be Jointly developed and integrated into domestic industries; for example, phosphate and gypsum, or bentonite for pelletized iron from the banded iron deposits. Other deposits such as barite and sepiolite are of value because of their proximity to major drilling operations in the Arabian Gulf. Still other deposits, such as alumina and banded iron, might be marketable because of proximity to aluminum and iron-refining industries now being constructed in Saudi Arabia. Some deposits, such as celestite, can be developed with little capital investment; others, such as the iron deposits, would require large capital commitments. Exploration and evaluation for many of these deposits can be accomplished by Somali geologists with a few advisors. Most of the deposits require feasibility studies conducted by teams of economic geologists, extractive metallurgists, and economists. Some marginal deposits could be exploited if cooperative development schemes could be negotiated with governments in nearby countries.

  8. Preparation, characterization, and preliminary antibrowning evaluations of norartocarpetin microemulsions.

    PubMed

    Zheng, Zong-Ping; Dong, Xue; Yuan, Kun; Lan, Shan; Zhu, Qin; Wang, Mingfu; Chen, Jie

    2015-02-11

    Norartocarpetin is a flavone widely distributed in Moraceae plants with strong tyrosinase inhibitory activity. However, its poor solubility in aqueous systems and in food grade solvents (oils) limits its extensive applications. The aim of this study was to improve the solubility of norartocarpetin by developing an oil-in-water (o/w) microemulsion with food grade components. A microemulsion was developed and characterized, and its chemical and physical stabilities were also evaluated within 8 weeks. Using the construction of pseudoternary phase diagrams, the optimized formulation of 2% w/w of ethyl oleate, 12% w/w of Tween 80, 6% w/w of polyethylene glycol 400, and 80% w/w of water was obtained, with a maximum solubility of norartocarpetin up to 1.73 ± 0.21 mg/mL, at least a 1000-fold increase in solubility. The microemulsion base and norartocarpetin-loaded microemulsion were demonstrated to be stable after accelerated and long-term conditions (8 weeks). The norartocarpetin microemulsion still showed strong tyrosinase inhibitory activity and antibrowning effect on fresh-cut apple slices. These combined results indicated that norartocarpetin microemulsion may be suitable as an antibrowning agent for fresh-cut fruits. PMID:25603116

  9. Inpatient treatment for depressed children and adolescents: preliminary evaluations.

    PubMed

    Robinson, R M; Powers, J M; Cleveland, P H; Thyer, B A

    1990-01-01

    Reported are the results of two uncontrolled outcome studies that evaluate the effectiveness of inpatient psychiatric treatment of children and adolescents suffering from clinical depression. Study 1 employed a sample of 7 children and measured outcome with the Depression Self-rating Scale (DSRS), the Hopelessness Scale for Children (HSC), and the Global Asssessment of Functioning (GAF) scale, which were administered to each child upon admission and again at discharge. Inpatient treatment involved multiple interventions, including individual psychotherapy, medication, milieu therapy and token economy, and other procedures. At discharge, statistically significant improvements were found on the patients' GAF and HSC scores, but not on their DSRS scores. Study 2 used a sample of 15 adolescents, also admitted for clinical depression. Administered at each patient's admission and discharge, the Beck Depression Inventory (BDI), Generalized Contentment Scale (GCS), and Index of Self-esteem (ISE) were used to measure outcome. The multi-modal treatment program offered to the sample in Study 2 was similar to that offered the sample in Study 1. At discharge all three outcome measures reflected statistically significant improvements in the patients studies; therefore, these results provide addmtional support for the inpatient treatment of depressed children and adolescents.

  10. [Preliminary evaluation of Chile's First Citizen Consensus Conference].

    PubMed

    Pellegrini Filho, Alberto; Zurita, Laura

    2004-05-01

    This piece provides an initial assessment of the First Citizen Consensus Conference, an event held in the city of Santiago, Chile, from 22-24 November 2003, on the subject of "The Management of My Medical Record." This conference was the first citizen consensus conference that has been held in Chile as well as the first such conference in Latin America. Consensus conferences were devised by the Danish Board of Technology in 1987 as a way to assess science and technology issues through discussions between experts and a panel of lay persons. At the end of a consensus conference, the lay persons express their opinions and recommendations in a consensus report that is directed at policymakers, decision-makers, and the public in general. The objective of a consensus conference is to bridge the gaps that routinely exist among the general public, experts, and elected officials. So far, the Danish Board of Technology has organized more than 20 of these conferences, using a methodology that has become established as a model. Taking into account the changes that have occurred in the relationship between science and society at large, the Pan American Health Organization has decided to support the holding of consensus conferences in Latin America and the Caribbean. The First Citizen Consensus Conference adapted the Danish methodology to conditions in Chile, and this piece assesses the modifications that were made. In addition, some 6 to 12 months after the conference, there will be an external evaluation of the outcomes and impact of the conference, especially in the communications media, public debate, decision-making, and perceptions of the persons who were involved. Despite the criticisms made in this piece and some shortcomings that are pointed out, the First Citizen Consensus Conference achieved all of its objectives and will serve as an excellent model for similar conferences in other countries of the Americas. PMID:15231085

  11. Preliminary ultrasound evaluation of the rotator cable in asymptomatic volunteers☆

    PubMed Central

    Orlandi, D.; Sconfienza, L.M.; Fabbro, E.; Ferrero, G.; Martini, C.; Lacelli, F.; Serafini, G.; Silvestri, E.

    2012-01-01

    Purpose To characterize the rotator cable high-resolution ultrasound appearance in asymptomatic shoulders of volunteers of different age. Materials and methods IRB approval and volunteers’ written consent was obtained. Excluding subjects with known shoulder affections, we screened 24 asymptomatic volunteers. Supraspinatus and infraspinatus tendons high-resolution ultrasound evaluation was performed according to standard scan protocols, further excluding shoulders with partial/full-thickness cuff tears. Thus, we studied 24 shoulders in 12 young volunteers (age range 21–39 years, mean age 33 ± 8 years) and 21 shoulders in 11 elderly volunteers (age range 62–83 years, mean age 75 ± 45 years). For each shoulder, we noted rotator cable visibility and its thickness and width. Fisher’s and U Mann–Whitney statistics were used. Results Rotator cable was less frequently detected in young than in elderly volunteers (5/24 vs. 11/21 shoulders; P = 0.034). When detected, rotator cable was significantly thicker in young (range 1.2–1.5 mm, mean thickness 1.3 ± 0.1 mm) than in elderly (range 0.9–1.4 mm, mean thickness 1.2 ± 0.1 mm) volunteers (P = 0.025), while its width was not significantly different in young (range 4.5–7.1 mm, mean 5.6 ± 1.1 mm) compared to elderly (range 2.5–7.1 mm, mean 4.2 ± 1.4 mm) volunteers (P = 0.074) although a tendency can be highlighted. Conclusions Ultrasound demonstrated the different consistency of rotator cable in young and elderly asymptomatic patients, with high interobserver reproducibility. PMID:23396940

  12. [Preliminary evaluation of Chile's First Citizen Consensus Conference].

    PubMed

    Pellegrini Filho, Alberto; Zurita, Laura

    2004-05-01

    This piece provides an initial assessment of the First Citizen Consensus Conference, an event held in the city of Santiago, Chile, from 22-24 November 2003, on the subject of "The Management of My Medical Record." This conference was the first citizen consensus conference that has been held in Chile as well as the first such conference in Latin America. Consensus conferences were devised by the Danish Board of Technology in 1987 as a way to assess science and technology issues through discussions between experts and a panel of lay persons. At the end of a consensus conference, the lay persons express their opinions and recommendations in a consensus report that is directed at policymakers, decision-makers, and the public in general. The objective of a consensus conference is to bridge the gaps that routinely exist among the general public, experts, and elected officials. So far, the Danish Board of Technology has organized more than 20 of these conferences, using a methodology that has become established as a model. Taking into account the changes that have occurred in the relationship between science and society at large, the Pan American Health Organization has decided to support the holding of consensus conferences in Latin America and the Caribbean. The First Citizen Consensus Conference adapted the Danish methodology to conditions in Chile, and this piece assesses the modifications that were made. In addition, some 6 to 12 months after the conference, there will be an external evaluation of the outcomes and impact of the conference, especially in the communications media, public debate, decision-making, and perceptions of the persons who were involved. Despite the criticisms made in this piece and some shortcomings that are pointed out, the First Citizen Consensus Conference achieved all of its objectives and will serve as an excellent model for similar conferences in other countries of the Americas.

  13. Synthesis and evaluation of boron compounds for neutron capture therapy of malignant brain tumors

    SciTech Connect

    Soloway, A.H.; Barth, R.F.

    1990-01-01

    Boron neutron capture therapy offers the potentiality for treating brain tumors currently resistant to treatment. The success of this form of therapy is directly dependent upon the delivery of sufficient numbers of thermal-neutrons to tumor cells which possess high concentrations of B-10. The objective of this project is to develop chemical methodology to synthesize boron-containing compounds with the potential for becoming incorporated into rapidly-dividing malignant brain tumor cells and excluded from normal components of the brain and surrounding tissues, to develope biological methods for assessing the potential of the compound by use of cell culture or intratumoral injection, to develop analytical methodology for measuring boron in cells and tissue using direct current plasma atomic emission spectroscopy (DCP-AES) and alpha track autoradiography, to develop biochemical and HPLC procedures for evaluating compound uptake and tissue half-life, and to develop procedures required to assess both in vitro and vivo efficacy of BNCT with selected compounds.

  14. Oak Ridge Reservation site evaluation report for the Advanced Neutron Source

    SciTech Connect

    Sigmon, B.; Heitzman, A.C. Jr.; Morrissey, J.

    1990-03-01

    The Advanced Neutron Source (ANS) is a research reactor that is the US Department of Energy (DOE) plans to build for initial service late in this century. The primary purpose of the ANS is to provide a useable neutron flux for scattering experiments 5 to 10 times as a high as that generated by any existing research reactor, secondary purposes include production of a variety of transuranic and other isotopes and irradiation of materials. The ANS is proposed to be located on the DOE Oak Ridge Reservation (ORR) at Oak Ridge, Tennessee, and operated by the Oak Ridge National Laboratory (ORNL). This report documents the evaluation of alternative sites on the ORR and the selection of a site for the ANS.

  15. Numerical evaluation of the light transport properties of alternative He-3 neutron detectors using ceramic scintillators

    NASA Astrophysics Data System (ADS)

    Ohzu, A.; Takase, M.; Haruyama, M.; Kurata, N.; Kobayashi, N.; Kureta, M.; Nakamura, T.; Toh, K.; Sakasai, K.; Suzuki, H.; Soyama, K.; Seya, M.

    2015-10-01

    The light transport properties of scintillator light inside alternative He-3 neutron detectors using scintillator sheets have been investigated by a ray-tracing simulation code. The detector consists of a light-reflecting tube, a thin rectangular ceramic scintillator sheet laminated on a glass plate, and two photo-multiplier tubes (PMTs) mounted at both ends of the detector tube. The flashes of light induced on the surface of the scintillator sheet via nuclear interaction between the scintillator and neutrons are detected by the two PMTs. The light output at both ends of various detectors in which the scintillator sheets are installed with several different arrangements were examined and evaluated in comparison with experimental results. The results derived from the simulation reveal that the light transport property is strongly dependent on the arrangement of the scintillator sheet inside the tube and the shape of the tube.

  16. Detection efficiency evaluation for a large area neutron sensitive microchannel plate detector

    NASA Astrophysics Data System (ADS)

    Wang, Yi-ming; Tian, Yang; Yang, Yi-gang; Liu, Ren; Pan, Jing-sheng; Wang, Xue-wu; Zhang, Zhi

    2016-09-01

    In this paper, the detection efficiency of a large area neutron sensitive microchannel plate detector has been evaluated. A 6LiF/ZnS scintillator detector 65 mm in diameter and 0.32 mm in thickness, with product code, EJ426HD2, produced by Eljen Technology, was employed as the benchmark detector. The TOF spectra of these two detectors were simultaneously measured and the energy spectra were then deduced to calculate the detection efficiency curve of the nMCP detector. Tests show the detection efficiency@25.3 meV thermal neutrons is 34% for this nMCP detector. Supported by National Natural Science Foundation of China (11375095, 11175098)

  17. Neutron Capture Cross Sections of 236U and 234U

    NASA Astrophysics Data System (ADS)

    Rundberg, R. S.; Bredeweg, T. A.; Bond, E. M.; Haight, R. C.; Hunt, L. F.; Kronenberg, A.; O'Donnell, J. M.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.

    2006-03-01

    Accurate neutron capture cross sections of the actinide elements at neutron energies up to 1 MeV are needed to better interpret archived nuclear test data, for post-detonation nuclear attribution, and the Advanced Fuel Cycle Initiative. The Detector for Advance Neutron Capture Experiments, DANCE, has unique capabilities that allow the differentiation of capture gamma rays from fission gamma rays and background gamma rays from scattered neutrons captured by barium isotopes in the barium fluoride scintillators. The DANCE array has a high granularity, 160 scintillators, high efficiency, and nearly 4-π solid angle. Through the use of cuts in cluster multiplicity and calorimetric energy the capture gamma-rays are differentiated from other sources of gamma rays. The preliminary results for the capture cross sections of 236U are in agreement with the ENDF/B-VI evaluation. The preliminary results for 234U lower are than ENDF/B-VI evaluation and are closer to older evaluations.

  18. Neutron Capture Cross Sections of 236U and 234U

    SciTech Connect

    Rundberg, R. S.; Bredeweg, T. A.; Bond, E. M.; Haight, R. C.; Hunt, L. F.; O'Donnell, J. M.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Kronenberg, A.

    2006-03-13

    Accurate neutron capture cross sections of the actinide elements at neutron energies up to 1 MeV are needed to better interpret archived nuclear test data, for post-detonation nuclear attribution, and the Advanced Fuel Cycle Initiative. The Detector for Advance Neutron Capture Experiments, DANCE, has unique capabilities that allow the differentiation of capture gamma rays from fission gamma rays and background gamma rays from scattered neutrons captured by barium isotopes in the barium fluoride scintillators. The DANCE array has a high granularity, 160 scintillators, high efficiency, and nearly 4-{pi} solid angle. Through the use of cuts in cluster multiplicity and calorimetric energy the capture gamma-rays are differentiated from other sources of gamma rays. The preliminary results for the capture cross sections of 236U are in agreement with the ENDF/B-VI evaluation. The preliminary results for 234U lower are than ENDF/B-VI evaluation and are closer to older evaluations.

  19. Evaluation of Am-Li neutron spectra data for active well type neutron multiplicity measurements of uranium

    NASA Astrophysics Data System (ADS)

    Goddard, Braden; Croft, Stephen; Lousteau, Angela; Peerani, Paolo

    2016-09-01

    Safeguarding nuclear material is an important and challenging task for the international community. One particular safeguards technique commonly used for uranium assay is active neutron correlation counting. This technique involves irradiating unused uranium with (α, n) neutrons from an Am-Li source and recording the resultant neutron pulse signal which includes induced fission neutrons. Although this non-destructive technique is widely employed in safeguards applications, the neutron energy spectra from an Am-Li sources is not well known. Several measurements over the past few decades have been made to characterize this spectrum; however, little work has been done comparing the measured and theoretical spectra of various Am-Li sources to each other. This paper examines fourteen different Am-Li spectra, focusing on how these spectra affect simulated neutron multiplicity results using the code Monte Carlo N-Particle eXtended (MCNPX). Two measurement and simulation campaigns were completed using Active Well Coincidence Counter (AWCC) detectors and uranium standards of varying enrichment. The results of this work indicate that for standard AWCC measurements, the fourteen Am-Li spectra produce similar doubles and triples count rates. The singles count rates varied by as much as 20% between the different spectra, although they are usually not used in quantitative analysis, being dominated by scattering which is highly dependent on item placement.

  20. Evaluation of Am–Li neutron spectra data for active well type neutron multiplicity measurements of uranium

    DOE PAGES

    Goddard, Braden; Croft, Stephen; Lousteau, Angela; Peerani, Paolo

    2016-05-25

    Safeguarding nuclear material is an important and challenging task for the international community. One particular safeguards technique commonly used for uranium assay is active neutron correlation counting. This technique involves irradiating unused uranium with ( α,n) neutrons from an Am-Li source and recording the resultant neutron pulse signal which includes induced fission neutrons. Although this non-destructive technique is widely employed in safeguards applications, the neutron energy spectra from an Am-Li sources is not well known. Several measurements over the past few decades have been made to characterize this spectrum; however, little work has been done comparing the measured spectra ofmore » various Am-Li sources to each other. This paper examines fourteen different Am-Li spectra, focusing on how these spectra affect simulated neutron multiplicity results using the code Monte Carlo N-Particle eXtended (MCNPX). Two measurement and simulation campaigns were completed using Active Well Coincidence Counter (AWCC) detectors and uranium standards of varying enrichment. The results of this work indicate that for standard AWCC measurements, the fourteen Am-Li spectra produce similar doubles and triples count rates. Finally, the singles count rates varied by as much as 20% between the different spectra, although they are usually not used in quantitative analysis.« less

  1. Cure4Kids for Kids: preliminary results on evaluating knowledge acquisition and knowledge retention.

    PubMed

    Quintana, Yuri; Van Kirk Villalobos, Aubrey; Li, Zhenghong; Kumar Srivastava, Deo; Ribeiro, Raul C

    2012-01-01

    Since 2006 St. Jude Children's Research Hospital has been developing Cure4Kids for Kids, a school-based outreach program to educate children about cancer and healthy lifestyles with a focus on cancer prevention. An evaluation of student knowledge acquisition and retention for the program at the Grade-4 level was conducted during the 2010-2011 school year. Preliminary results of this evaluation are outlined with some of the challenges for long-term program evaluation of cancer prevention programs. PMID:22910510

  2. Micro-focused Small Angle Neutron Scattering and Imaging for Science and Engineering Using RTP--A Preliminary Study

    SciTech Connect

    Mohamed, Abdul Aziz; Al Rashid Megat Ahmad, Megat Harun; Md Idris, Faridah; Azman, Azraf; Jamro, Rafhayudi; Ibrahim, Mohd Rizal Mamat; Rahman, Anwar Abdul

    2010-01-05

    Malaysian Nuclear Agency's (Nuclear Malaysia) Small Angle Neutron Scattering (SANS) facility--(MYSANS)--is utilizing low flux of thermal neutron at the agency's 1 MW TRIGA reactor. As the design nature of the 8 m SANS facility can allow object resolution in the range between 5 and 80 nm to be obtained. It can be used to study alloys, ceramics and polymers in certain area of problems that relate to samples containing strong scatterers or contrast. The current SANS system at Malaysian Nuclear Agency is only capable to measure Q in limited range with a PSD (128x128) fixed at 4 m from the sample. The existing reactor hall that incorporate this MYSANS facility has a layout that prohibits the rebuilding of MYSANS therefore the position between the wavelength selector (HOPG) and sample and the PSD cannot be increased for wider Q range. The flux of the neutron at current sample holder is very low which around 10{sup 3} n/cm{sup 2}/sec. Thus it is important to rebuild the MYSANS to maximize the utilization of neutron. Over the years, the facility has undergone maintenance and some changes have been made. Modification on secondary shutter and control has been carried out to improve the safety level of the instrument. A compact micro-focus SANS method can suit this objective together with an improve cryostat system. This paper will explain some design concept and approaches in achieving higher flux and the modification needs to establish the micro-focused SANS.

  3. Micro-focused Small Angle Neutron Scattering and Imaging for Science and Engineering Using RTP—A Preliminary Study

    NASA Astrophysics Data System (ADS)

    Mohamed, Abdul Aziz; Al Rashid Megat Ahmad, Megat Harun; Md Idris, Faridah; Azman, Azraf; Jamro, Rafhayudi; Ibrahim, Mohd Rizal Mamat; Rahman, Anwar Abdul

    2010-01-01

    Malaysian Nuclear Agency's (Nuclear Malaysia) Small Angle Neutron Scattering (SANS) facility—(MYSANS)—is utilizing low flux of thermal neutron at the agency's 1 MW TRIGA reactor. As the design nature of the 8 m SANS facility can allow object resolution in the range between 5 and 80 nm to be obtained. It can be used to study alloys, ceramics and polymers in certain area of problems that relate to samples containing strong scatterers or contrast. The current SANS system at Malaysian Nuclear Agency is only capable to measure Q in limited range with a PSD (128×128) fixed at 4 m from the sample. The existing reactor hall that incorporate this MYSANS facility has a layout that prohibits the rebuilding of MYSANS therefore the position between the wavelength selector (HOPG) and sample and the PSD cannot be increased for wider Q range. The flux of the neutron at current sample holder is very low which around 103 n/cm2/sec. Thus it is important to rebuild the MYSANS to maximize the utilization of neutron. Over the years, the facility has undergone maintenance and some changes have been made. Modification on secondary shutter and control has been carried out to improve the safety level of the instrument. A compact micro-focus SANS method can suit this objective together with an improve cryostat system. This paper will explain some design concept and approaches in achieving higher flux and the modification needs to establish the micro-focused SANS.

  4. Evaluation of Neutron Radiography Reactor LEU-Core Start-Up Measurements

    SciTech Connect

    Bess, John D.; Maddock, Thomas L.; Smolinski, Andrew T.; Marshall, Margaret A.

    2014-11-04

    Benchmark models were developed to evaluate the cold-critical start-up measurements performed during the fresh core reload of the Neutron Radiography (NRAD) reactor with Low Enriched Uranium (LEU) fuel. Experiments include criticality, control-rod worth measurements, shutdown margin, and excess reactivity for four core loadings with 56, 60, 62, and 64 fuel elements. The worth of four graphite reflector block assemblies and an empty dry tube used for experiment irradiations were also measured and evaluated for the 60-fuel-element core configuration. Dominant uncertainties in the experimental keff come from uncertainties in the manganese content and impurities in the stainless steel fuel cladding as well as the 236U and erbium poison content in the fuel matrix. Calculations with MCNP5 and ENDF/B-VII.0 neutron nuclear data are approximately 1.4% (9σ) greater than the benchmark model eigenvalues, which is commonly seen in Monte Carlo simulations of other TRIGA reactors. Simulations of the worth measurements are within the 2σ uncertainty for most of the benchmark experiment worth values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.

  5. Evaluation of Neutron Radiography Reactor LEU-Core Start-Up Measurements

    DOE PAGES

    Bess, John D.; Maddock, Thomas L.; Smolinski, Andrew T.; Marshall, Margaret A.

    2014-11-04

    Benchmark models were developed to evaluate the cold-critical start-up measurements performed during the fresh core reload of the Neutron Radiography (NRAD) reactor with Low Enriched Uranium (LEU) fuel. Experiments include criticality, control-rod worth measurements, shutdown margin, and excess reactivity for four core loadings with 56, 60, 62, and 64 fuel elements. The worth of four graphite reflector block assemblies and an empty dry tube used for experiment irradiations were also measured and evaluated for the 60-fuel-element core configuration. Dominant uncertainties in the experimental keff come from uncertainties in the manganese content and impurities in the stainless steel fuel cladding asmore » well as the 236U and erbium poison content in the fuel matrix. Calculations with MCNP5 and ENDF/B-VII.0 neutron nuclear data are approximately 1.4% (9σ) greater than the benchmark model eigenvalues, which is commonly seen in Monte Carlo simulations of other TRIGA reactors. Simulations of the worth measurements are within the 2σ uncertainty for most of the benchmark experiment worth values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.« less

  6. An Evaluation of Neutron Energy Spectrum Effects in Iron Based on Molecular Dynamics Displacement Cascade Simulations

    SciTech Connect

    Stoller, R.E.; Greenwood, L.R.

    1998-06-16

    The results of molecular dynamics (MD) displacement cascade simulations in bcc iron have been used to obtain effective cross sections for two measures of primary damage production: (1) the number of surviving point defects expressed as a fraction of the displacements calculated using the standard secondary displacement model of Norgett, Robinson, and Torrens (NRT), and (2) the fraction of the surviving interstitials contained in clusters that formed during the cascade event. Primary knockon atom spectra for iron obtained from the SPECTER code have been used to weight these MD-based damage production cross sections in order to obtain spectrally-averaged values for several locations in commercial fission reactors and materials test reactors. An evaluation of these results indicates that neutron energy spectrum differences between the various enviromnents do not lead to significant differences between the average primary damage formation parameters. In particular, the defect production cross sections obtained for PWR and BWR neutron spectra were not significantly different. The variation of the defect production cross sections as a function of depth into the reactor pressure vessel wall is used as a sample application of the cross sections. A slight difference between the attenuation behavior of the PWR and BWR was noted; this difference could be explained by a subtle difference in the energy dependence of the neutron spectra. Overall, the simulations support the continued use of dpa as a damage correlation parameter.

  7. Evaluation of a personal and environmental dosemeter based on CR-39 track detectors in quasi-monoenergetic neutron fields.

    PubMed

    Caresana, M; Ferrarini, M; Parravicini, A; Sashala Naik, A

    2014-10-01

    In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV. The results showed a response that is almost independent of the neutron energy in the whole energy range.

  8. Evaluation of Beta-Delayed Neutron Emission Probabilities and Half-Lives for Z = 2–28

    SciTech Connect

    Birch, M.; Singh, B.; Dillmann, I.; Abriola, D.; Johnson, T.D.; McCutchan, E.A.; Sonzogni, A.A.

    2015-09-15

    We present an evaluation and compilation of β-delayed neutron probabilities and half-lives for nuclei in the region Z = 2–28 ({sup 8}He–{sup 80}Ni). This article includes the recommended values of these quantities as well as a compiled list of experimental measurements for each nucleus in the region for which β-delayed neutron emission is possible. The literature cut-off for this work is August 15{sup th}, 2015. Some notable cases as well as new standards for β-delayed neutron measurements in this mass region are also discussed.

  9. Evaluation of a personal and environmental dosemeter based on CR-39 track detectors in quasi-monoenergetic neutron fields.

    PubMed

    Caresana, M; Ferrarini, M; Parravicini, A; Sashala Naik, A

    2014-10-01

    In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV. The results showed a response that is almost independent of the neutron energy in the whole energy range. PMID:24324248

  10. Development of a high spatial resolution neutron imaging system and performance evaluation

    NASA Astrophysics Data System (ADS)

    Cao, Lei

    The combination of a scintillation screen and a charged coupled device (CCD) camera is a digitized neutron imaging technology that has been widely employed for research and industry application. The maximum of spatial resolution of scintillation screens is in the range of 100 mum and creates a bottleneck for the further improvement of the overall system resolution. In this investigation, a neutron sensitive micro-channel plate (MCP) detector with pore pitch of 11.4 mum is combined with a cooled CCD camera with a pixel size of 6.8 mum to provide a high spatial resolution neutron imaging system. The optical path includes a high reflection front surface mirror for keeping the camera out of neutron beam and a macro lens for achieving the maximum magnification that could be achieved. All components are assembled into an aluminum light tight box with heavy radiation shielding to protect the camera as well as to provide a dark working condition. Particularly, a remote controlled stepper motor is also integrated into the system to provide on-line focusing ability. The best focus is guaranteed through use of an algorithm instead of perceptual observation. An evaluation routine not previously utilized in the field of neutron radiography is developed in this study. Routines like this were never previously required due to the lower resolution of other systems. Use of the augulation technique to obtain presampled MTF addresses the problem of aliasing associated with digital sampling. The determined MTF agrees well with the visual inspection of imaging a testing target. Other detector/camera combinations may be integrated into the system and their performances are also compared. The best resolution achieved by the system at the TRIGA Mark II reactor at the University of Texas at Austin is 16.2 lp/mm, which is equivalent to a minimum resolvable spacing of 30 mum. The noise performance of the device is evaluated in terms of the noise power spectrum (NPS) and the detective quantum

  11. Preliminary joint X-ray and neutron protein crystallographic studies of ecDHFR complexed with folate and NADP+.

    PubMed

    Wan, Qun; Kovalevsky, Andrey Y; Wilson, Mark A; Bennett, Brad C; Langan, Paul; Dealwis, Chris

    2014-06-01

    A crystal of Escherichia coli dihydrofolate reductase (ecDHFR) complexed with folate and NADP+ of 4×1.3×0.7 mm (3.6 mm3) in size was obtained by sequential application of microseeding and macroseeding. A neutron diffraction data set was collected to 2.0 Å resolution using the IMAGINE diffractometer at the High Flux Isotope Reactor within Oak Ridge National Laboratory. A 1.6 Å resolution X-ray data set was also collected from a smaller crystal at room temperature. The neutron and X-ray data were used together for joint refinement of the ecDHFR-folate-NADP+ ternary-complex structure in order to examine the protonation state, protein dynamics and solvent structure of the complex, furthering understanding of the catalytic mechanism.

  12. Improved Modeling of Prompt Fission Neutron Spectra for Nuclear Data Evaluations

    NASA Astrophysics Data System (ADS)

    Neudecker, Denise; Talou, Patrick; Kawano, Toshihiko; Kahler, Albert C.; White, Morgan C.

    2015-10-01

    The prompt fission neutron spectra (PFNS) of major actinides such as 239Pu and 235U are quantities of interest for nuclear physics application areas including reactor physics and national security. Nuclear data evaluations provide recommended data for those application areas based on nuclear theory and experiments. Here, we present improvements made to the effective models predicting the PFNS up to incident neutron energies of 30 MeV and their impact on evaluations. These models describe relevant physics processes better than those used for the current US nuclear data library ENDF/B-VII.1. In addition, the use of higher-fidelity models such as Monte Carlo Hauser-Feshbach calculations will be discussed in the context of future PFNS evaluations. (LA-UR-15-24763) This work was carried out under the auspices of the US Department of Energy, National Nuclear Security Administration and Office of Science, and performed by Los Alamos National Security LLC under Contract DE-AC52-06NA25396.

  13. Advanced modeling of prompt fission neutrons

    SciTech Connect

    Talou, Patrick

    2009-01-01

    Theoretical and numerical studies of prompt fission neutrons are presented. The main results of the Los Alamos model often used in nuclear data evaluation work are reviewed briefly, and a preliminary assessment of uncertainties associated with the evaluated prompt fission neutron spectrum for n (0.5 MeV)+{sup 239}Pu is discussed. Advanced modeling of prompt fission neutrons is done by Monte Carlo simulations of the evaporation process of the excited primary fission fragments. The successive emissions of neutrons are followed in the statistical formalism framework, and detailed information, beyond average quantities, can be inferred. This approach is applied to the following reactions: {sup 252}Cf (sf), n{sub th} + {sup 239}Pu, n (0.5 MeV)+{sup 235}U, and {sup 236}Pu (sf). A discussion on the merits and present limitations of this approach concludes this presentation.

  14. Preliminary survey and evaluation of nonaquifer thermal energy storage concepts for seasonal storage

    SciTech Connect

    Blahnik, D.E.

    1980-11-01

    Thermal energy storage enables the capture and retention of heat energy (or cold) during one time period for use during another. Seasonal thermal energy storage (STES) involves a period of months between the input and recovery of energy. The purpose of this study was to make a preliminary investigation and evaluation of potential nonaquifer STES systems. Current literature was surveyed to determine the state of the art of thermal energy storage (TES) systems such as hot water pond storage, hot rock storage, cool ice storage, and other more sophisticated concepts which might have potential for future STES programs. The main energy sources for TES principally waste heat, and the main uses of the stored thermal energy, i.e., heating, cooling, and steam generation are described. This report reviews the development of sensible, latent, and thermochemical TES technologies, presents a preliminary evaluation of the TES methods most applicable to seasonal storage uses, outlines preliminary conclusions drawn from the review of current TES literature, and recommends further research based on these conclusions. A bibliography of the nonaquifer STES literature review, and examples of 53 different TES concepts drawn from the literature are provided. (LCL)

  15. Evaluating secondary neutron doses of a refined shielded design for a medical cyclotron using the TLD approach

    NASA Astrophysics Data System (ADS)

    Lin, Jye-Bin; Tseng, Hsien-Chun; Liu, Wen-Shan; Lin, Ding-Bang; Hsieh, Teng-San; Chen, Chien-Yi

    2013-11-01

    An increasing number of cyclotrons at medical centers in Taiwan have been installed to generate radiopharmaceutical products. An operating cyclotron generates immense amounts of secondary neutrons from reactions such the 18O(p, n)18F, used in the production of FDG. This intense radiation can be hazardous to public health, particularly to medical personnel. To increase the yield of 18F-FDG from 4200 GBq in 2005 to 48,600 GBq in 2011, Chung Shan Medical University Hospital (CSMUH) has prolonged irradiation time without changing the target or target current to meet requirements regarding the production 18F. The CSMUH has redesigned the CTI Radioisotope Delivery System shield. The lack of data for a possible secondary neutron doses has increased due to newly designed cyclotron rooms. This work aims to evaluate secondary neutron doses at a CTI cyclotron center using a thermoluminescent dosimeter (TLD-600). Two-dimensional neutron doses were mapped and indicated that neutron doses were high as neutrons leaked through self-shielded blocks and through the L-shaped concrete shield in vault rooms. These neutron doses varied markedly among locations close to the H218O target. The Monte Carlo simulation and minimum detectable dose are also discussed and demonstrated the reliability of using the TLD-600 approach. Findings can be adopted by medical centers to identify radioactive hot spots and develop radiation protection.

  16. Preliminary evaluation of wheelchair occupant restraint system usage in motor vehicles.

    PubMed

    van Roosmalen, Linda; Bertocci, Gina E; Hobson, Douglas A; Karg, Patricia

    2002-01-01

    Individuals using wheeled mobility devices (WMDs) often use them as motor vehicle seats during transportation. Wheelchair occupant restraint systems (WORSs), consisting of upper torso and pelvic restraints, are usually mounted to the structure of transit vehicles to secure individuals within their wheelchair seats. This preliminary study attempts to evaluate the use and satisfaction of currently installed vehicle-mounted WORSs for individuals using WMD as seats in motor vehicles. A survey was conducted among 33 adults who use their WMD to travel in motor vehicles. Results from the survey showed that upper torso and pelvic restraints installed in private vehicles are quick, comfortable, and easy to use. However, WORS installed in mass transit and paratransit are often uncomfortable to wear, difficult to reach, and time-consuming to use. This preliminary study documents the growing need for developing alternative WORS that are safe, comfortable, and that allow independent usage for wheelchair occupants while traveling in a motor vehicle.

  17. Preliminary evaluation of beta-spodumene as a fusion reactor structural material

    SciTech Connect

    Kelsey, P.V. Jr.; Schmunk, R.E.; Henslee, S.P.

    1981-01-01

    Beta-spodumene was investigated as a candidate material for use in fusion reactor environments. Properties which support the use of beta-spodumene include good thermal shock resistance, a very low coefficient of thermal expansion, a low-Z composition which would result in minimum impact on the plasma, and flexibility in fabrication processes. Specimens were irradiated in the Advanced Test Reactor (ATR) to a fluence of 5.3 x 10/sup 22/ n/m/sup 2/, E > 0.1 MeV, and 4.9 x 10/sup 23/ n/m/sup 2/ thermal fluence in order to obtain a preliminary evaluation of the impact of irradiation on the material. Preliminary data indicate that the mechanical properties of beta-spodumene are little affected by irradiation. Gas production and release have also been investigated.

  18. Methodology for worker neutron exposure evaluation in the PDCF facility design.

    PubMed

    Scherpelz, R I; Traub, R J; Pryor, K H

    2004-01-01

    A project headed by Washington Group International is meant to design the Pit Disassembly and Conversion Facility (PDCF) to convert the plutonium pits from excessed nuclear weapons into plutonium oxide for ultimate disposition. Battelle staff are performing the shielding calculations that will determine appropriate shielding so that the facility workers will not exceed target exposure levels. The target exposure levels for workers in the facility are 5 mSv y(-1) for the whole body and 100 mSv y(-1) for the extremity, which presents a significant challenge to the designers of a facility that will process tons of radioactive material. The design effort depended on shielding calculations to determine appropriate thickness and composition for glove box walls, and concrete wall thicknesses for storage vaults. Pacific Northwest National Laboratory (PNNL) staff used ORIGEN-S and SOURCES to generate gamma and neutron source terms, and Monte Carlo (computer code for) neutron photon (transport) (MCNP-4C) to calculate the radiation transport in the facility. The shielding calculations were performed by a team of four scientists, so it was necessary to develop a consistent methodology. There was also a requirement for the study to be cost-effective, so efficient methods of evaluation were required. The calculations were subject to rigorous scrutiny by internal and external reviewers, so acceptability was a major feature of the methodology. Some of the issues addressed in the development of the methodology included selecting appropriate dose factors, developing a method for handling extremity doses, adopting an efficient method for evaluating effective dose equivalent in a non-uniform radiation field, modelling the reinforcing steel in concrete, and modularising the geometry descriptions for efficiency. The relative importance of the neutron dose equivalent compared with the gamma dose equivalent varied substantially depending on the specific shielding conditions and lessons

  19. METHODOLOGY FOR WORKER NEUTRON EXPOSURE EVALUATION IN THE PDCF FACILITY DESIGN

    SciTech Connect

    Scherpelz, Robert I.; Traub, Richard J.; Pryor, Kathryn H.

    2004-08-01

    A project headed by Washington Group International is meant to design the Pit Disassembly and Conversion Facility (PDCF) to convert the plutonium pits from excessed nuclear weapons into plutonium oxide for ultimate disposition. Battelle staff are performing the shielding calculations that will determine appropriate shielding so that the facility workers will not exceed target exposure levels. The target exposure levels for workers in the facility are 5 mSv y?1 for the whole body and 100 mSv y?1 for the extremity, which presents a significant challenge to the designers of a facility that will process tons of radioactive material. The design effort depended on shielding calculations to determine appropriate thickness and composition for glove box walls, and concrete wall thicknesses for storage vaults. Pacific Northwest National Laboratory (PNNL) staff used ORIGEN-S and SOURCES to generate gamma and neutron source terms, and Monte Carlo (computer code for) neutron photon (transport) (MCNP-4C) to calculate the radiation transport in the facility. The shielding calculations were performed by a team of four scientists, so it was necessary to develop a consistent methodology. There was also a requirement for the study to be cost-effective, so efficient methods of evaluation were required. The calculations were subject to rigorous scrutiny by internal and external reviewers, so acceptability was a major feature of the methodology. Some of the issues addressed in the development of the methodology included selecting appropriate dose factors, developing a method for handling extremity doses, adopting an efficient method for evaluating effective dose equivalent in a non-uniform radiation field, modeling the reinforcing steel in concrete, and modularizing the geometry descriptions for efficiency. The relative importance of the neutron dose equivalent compared with the gamma dose equivalent varied substantially depending on the specific shielding conditions and lessons were

  20. Methodology for worker neutron exposure evaluation in the PDCF facility design.

    PubMed

    Scherpelz, R I; Traub, R J; Pryor, K H

    2004-01-01

    A project headed by Washington Group International is meant to design the Pit Disassembly and Conversion Facility (PDCF) to convert the plutonium pits from excessed nuclear weapons into plutonium oxide for ultimate disposition. Battelle staff are performing the shielding calculations that will determine appropriate shielding so that the facility workers will not exceed target exposure levels. The target exposure levels for workers in the facility are 5 mSv y(-1) for the whole body and 100 mSv y(-1) for the extremity, which presents a significant challenge to the designers of a facility that will process tons of radioactive material. The design effort depended on shielding calculations to determine appropriate thickness and composition for glove box walls, and concrete wall thicknesses for storage vaults. Pacific Northwest National Laboratory (PNNL) staff used ORIGEN-S and SOURCES to generate gamma and neutron source terms, and Monte Carlo (computer code for) neutron photon (transport) (MCNP-4C) to calculate the radiation transport in the facility. The shielding calculations were performed by a team of four scientists, so it was necessary to develop a consistent methodology. There was also a requirement for the study to be cost-effective, so efficient methods of evaluation were required. The calculations were subject to rigorous scrutiny by internal and external reviewers, so acceptability was a major feature of the methodology. Some of the issues addressed in the development of the methodology included selecting appropriate dose factors, developing a method for handling extremity doses, adopting an efficient method for evaluating effective dose equivalent in a non-uniform radiation field, modelling the reinforcing steel in concrete, and modularising the geometry descriptions for efficiency. The relative importance of the neutron dose equivalent compared with the gamma dose equivalent varied substantially depending on the specific shielding conditions and lessons

  1. Bayesian Evaluation Including Covariance Matrices of Neutron-induced Reaction Cross Sections of {sup 181}Ta

    SciTech Connect

    Leeb, H. Schnabel, G.; Srdinko, Th.; Wildpaner, V.

    2015-01-15

    A new evaluation of neutron-induced reactions on {sup 181}Ta using a consistent procedure based on Bayesian statistics is presented. Starting point of the evaluation is the description of nuclear reactions via nuclear models implemented in TALYS 1.4. A retrieval of experimental data was performed and covariance matrices of the experiments were generated from an extensive study of the corresponding literature. All reaction channels required for a transport file up to 200 MeV have been considered and the covariance matrices of cross section uncertainties for the most important channels are determined. The evaluation has been performed in one step including all available experimental data. A comparison of the evaluated cross sections and spectra with experimental data and available evaluations is performed. In general the evaluated cross section reflect our best knowledge and give a fair description of the observables. However, there are few deviations from expectation which clearly indicate the impact of the prior and the need to account for model defects. Using the results of the evaluation a complete ENDF-file similarly to those of the TENDL library is generated.

  2. Impact of the γ _{ν }NN* Electrocoupling Parameters at High Photon Virtualities and Preliminary Cross Sections off the Neutron

    NASA Astrophysics Data System (ADS)

    Gothe, Ralf W.; Tian, Ye

    2016-10-01

    Meson-photoproduction measurements and their reaction-amplitude analyses can establish more sensitively, and in some cases in an almost model-independent way, nucleon excitations and non-resonant reaction amplitudes. However, to investigate the strong interaction from already explored—where meson-cloud degrees of freedom contribute substantially to the baryon structure—to still unexplored distance scales—where quark degrees of freedom dominate and the transition from dressed to current quarks occurs—we depend on experiments that allow us to measure observables that are probing this evolving non-perturbative QCD regime over its full range. Elastic and transition form factors are uniquely suited to trace this evolution by measuring elastic electron scattering and exclusive single-meson and double-pion electroproduction cross sections off the nucleon. These exclusive measurements will be extended to higher momentum transfers with the energy-upgraded CEBAF beam at JLab to study the quark degrees of freedom, where their strong interaction is responsible for the ground and excited nucleon state formations. After establishing unprecedented high-precision data, the imminent next challenge is a high-quality analysis to extract these relevant electrocoupling parameters for various resonances that can then be compared to state-of-the-art models and QCD-based calculations. The vast majority of the available exclusive electroproduction cross sections are off the proton. Hence flavor-dependent analyses of excited light-quark baryons are lacking experimental data off the neutron. The goal is to close this gap by providing exclusive {γ }_{ν }(n) → p+ {π }- reaction cross section off deuterium and to establish a kinematical final-state-interaction (FSI) correction factor (R) map that can be determined from the data set itself. The "e1e" Jefferson Lab CLAS data set, that is analyzed, includes both a hydrogen and deuterium target run period, which allows a combined

  3. Preliminary assessment of the nuclide migration from the activation zone around the proposed Spallation Neutron Source facility

    SciTech Connect

    Dole, L.R.

    1998-09-01

    The purpose of this study is to investigate the potential impacts of migrating radionuclides from the activation zone around the proposed Spallation Neutron Source (SNS). Using conservatively high estimates of the potential inventory of radioactive activation products that could form in the proposed compacted-soil shield berm around an SNS facility on the Oak Ridge Reservation (ORR), a conservative, simplified transport model was used to estimate the potential worst-case concentrations of the 12 long-lived isotopes in the groundwater under a site with the hydrologic characteristics of the ORR.

  4. Impact of the γ _{ν } NN* Electrocoupling Parameters at High Photon Virtualities and Preliminary Cross Sections off the Neutron

    NASA Astrophysics Data System (ADS)

    Gothe, Ralf W.; Tian, Ye

    2016-06-01

    Meson-photoproduction measurements and their reaction-amplitude analyses can establish more sensitively, and in some cases in an almost model-independent way, nucleon excitations and non-resonant reaction amplitudes. However, to investigate the strong interaction from already explored—where meson-cloud degrees of freedom contribute substantially to the baryon structure—to still unexplored distance scales—where quark degrees of freedom dominate and the transition from dressed to current quarks occurs—we depend on experiments that allow us to measure observables that are probing this evolving non-perturbative QCD regime over its full range. Elastic and transition form factors are uniquely suited to trace this evolution by measuring elastic electron scattering and exclusive single-meson and double-pion electroproduction cross sections off the nucleon. These exclusive measurements will be extended to higher momentum transfers with the energy-upgraded CEBAF beam at JLab to study the quark degrees of freedom, where their strong interaction is responsible for the ground and excited nucleon state formations. After establishing unprecedented high-precision data, the imminent next challenge is a high-quality analysis to extract these relevant electrocoupling parameters for various resonances that can then be compared to state-of-the-art models and QCD-based calculations. The vast majority of the available exclusive electroproduction cross sections are off the proton. Hence flavor-dependent analyses of excited light-quark baryons are lacking experimental data off the neutron. The goal is to close this gap by providing exclusive {γ }_{ν }(n) → p+ {π }- reaction cross section off deuterium and to establish a kinematical final-state-interaction (FSI) correction factor (R) map that can be determined from the data set itself. The "e1e" Jefferson Lab CLAS data set, that is analyzed, includes both a hydrogen and deuterium target run period, which allows a combined

  5. Naturally induced secondary radiation in interplanetary space: Preliminary analyses for gamma radiation and radioisotope production from thermal neutron activation

    NASA Technical Reports Server (NTRS)

    Plaza-Rosado, Heriberto

    1991-01-01

    Thermal neutron activation analyses were carried out for various space systems components to determine gamma radiation dose rates and food radiation contamination levels. The space systems components selected were those for which previous radiation studies existed. These include manned space vehicle radiation shielding, liquid hydrogen propellant tanks for a Mars mission, and a food supply used as space vehicle radiation shielding. The computational method used is based on the fast neutron distribution generated by the BRYNTRN and HZETRN transport codes for Galactic Cosmic Rays (GCR) at solar minimum conditions and intense solar flares in space systems components. The gamma dose rates for soft tissue are calculated for water and aluminum space vehicle slab shields considering volumetric source self-attenuation and exponential buildup factors. In the case of the lunar habitat with regolith shielding, a completely exposed spherical habitat was assumed for mathematical convenience and conservative calculations. Activation analysis of the food supply used as radiation shielding is presented for four selected nutrients: potassium, calcium, sodium, and phosphorus. Radioactive isotopes that could represent a health hazard if ingested are identified and their concentrations are identified. For nutrients soluble in water, it was found that all induced radioactivity was below the accepted maximum permissible concentrations.

  6. Identification and preliminary evaluation of polychlorinated naphthalene emissions from hot dip galvanizing plants.

    PubMed

    Liu, Guorui; Lv, Pu; Jiang, Xiaoxu; Nie, Zhiqiang; Liu, Wenbin; Zheng, Minghui

    2015-01-01

    Hot dip galvanizing (HDG) processes are sources of polychlorinated-p-dioxins and dibenzofurans (PCDD/Fs). Close correlations have been found between the concentration of PCDD/Fs and polychlorinated naphthalenes (PCNs) that are produced and released during industrial thermal processes. We speculated, therefore, that HDG plants are potential PCN sources. In this preliminary study, PCNs were analyzed in solid residues, ash and precipitate from three HDG plants of different sizes. The total PCN concentrations (∑2-8PCNs) in the residue samples ranged from 60.3 to 226pgg(-1). The PCN emission factors for the combined ash and precipitate residues from the HDG plants ranged from 75 to 178ngt(-1) for the dichlorinated and octachlorinated naphthalenes. The preliminary results suggested that the HDG industry might not currently be a significant source of PCN emissions. The trichloronaphthalenes were the dominant homologs followed by the dichloronaphthalenes and the tetrachloronaphthalenes. The PCN congeners CN37/33/34, CN52/60, CN66/67, and CN73 dominated the tetrachlorinated, pentachlorinated, hexachlorinated, and heptachlorinated naphthalene homologs, respectively. The PCNs emitted from the HDG plants had similar homolog distributions and congener profiles to the PCNs emitted from combustion plants and other metallurgical processes. The identification and preliminary evaluation of PCN emissions from HDG plants presented here will help in the prioritization of measures for controlling PCN emissions from industrial sources.

  7. Covariances Obtained from an Evaluation of the Neutron Cross Section Standards

    SciTech Connect

    Carlson, A. D.; Badikov, S. A.; Chen, Zhenpeng; Gai, E.; Pronyaev, V. G.; Hale, G. M.; Kawano, T.; Hambsch, F.; Hoffman, H.; Larson, Nancy M; Oli, S.; Smith, D. L.; Tagesen, S.; Vonach, H.

    2008-12-01

    New measurements and an improved evaluation process were used to obtain a new evaluation of the neutron cross section standards. Efforts were made to include as much information as possible on the components of the data uncertainties that were then used to obtain the covariance matrices for the experimental data. Evaluations were produced from this process for the 6Li(n,t), 10B(n, ), 10B(n, 1 ), 197Au(n, ), 235U(n,f), and 238U(n,f) standard cross sections as well as the non-standard 6Li(n,n), 10B(n,n), 238U(n, ) and 239Pu(n,f) cross sections. There is a general increase in the cross sections for most of the new evaluations, by as much as about 5%, compared with the ENDF/B-VI results. Covariance data were obtained for the 6Li(n,t), 6Li(n,n), 10B(n, ), 10B(n, 1 ), 10B(n,n), 197Au(n, ), 235U(n,f), 238U(n,f), 238U(n, ) and 239Pu(n,f) reactions. Also an independent R-Matrix evaluation was produced for the H(n,n) standard cross-section, however, covariance data are not available for this reaction. The evaluations were used in the new ENDF/B-VII library.

  8. Evaluation of the ²³⁹Pu prompt fission neutron spectrum induced by neutrons of 500 keV and associated covariances

    DOE PAGES

    Neudecker, D.; Talou, P.; Kawano, T.; Smith, D. L.; Capote, R.; Rising, M. E.; Kahler, A. C.

    2015-08-01

    We present evaluations of the prompt fission neutron spectrum (PFNS) of ²³⁹Pu induced by 500 keV neutrons, and associated covariances. In a previous evaluation by Talou et al. 2010, surprisingly low evaluated uncertainties were obtained, partly due to simplifying assumptions in the quantification of uncertainties from experiment and model. Therefore, special emphasis is placed here on a thorough uncertainty quantification of experimental data and of the Los Alamos model predicted values entering the evaluation. In addition, the Los Alamos model was extended and an evaluation technique was employed that takes into account the qualitative differences between normalized model predicted valuesmore » and experimental shape data. These improvements lead to changes in the evaluated PFNS and overall larger evaluated uncertainties than in the previous work. However, these evaluated uncertainties are still smaller than those obtained in a statistical analysis using experimental information only, due to strong model correlations. Hence, suggestions to estimate model defect uncertainties are presented, which lead to more reasonable evaluated uncertainties. The calculated keff of selected criticality benchmarks obtained with these new evaluations agree with each other within their uncertainties despite the different approaches to estimate model defect uncertainties. The keff one standard deviations overlap with some of those obtained using ENDF/B-VII.1, albeit their mean values are further away from unity. Spectral indexes for the Jezebel critical assembly calculated with the newly evaluated PFNS agree with the experimental data for selected (n,γ) and (n,f) reactions, and show improvements for high-energy threshold (n,2n) reactions compared to ENDF/B-VII.1.« less

  9. Evaluation of the ²³⁹Pu prompt fission neutron spectrum induced by neutrons of 500 keV and associated covariances

    SciTech Connect

    Neudecker, D.; Talou, P.; Kawano, T.; Smith, D. L.; Capote, R.; Rising, M. E.; Kahler, A. C.

    2015-08-01

    We present evaluations of the prompt fission neutron spectrum (PFNS) of ²³⁹Pu induced by 500 keV neutrons, and associated covariances. In a previous evaluation by Talou et al. 2010, surprisingly low evaluated uncertainties were obtained, partly due to simplifying assumptions in the quantification of uncertainties from experiment and model. Therefore, special emphasis is placed here on a thorough uncertainty quantification of experimental data and of the Los Alamos model predicted values entering the evaluation. In addition, the Los Alamos model was extended and an evaluation technique was employed that takes into account the qualitative differences between normalized model predicted values and experimental shape data. These improvements lead to changes in the evaluated PFNS and overall larger evaluated uncertainties than in the previous work. However, these evaluated uncertainties are still smaller than those obtained in a statistical analysis using experimental information only, due to strong model correlations. Hence, suggestions to estimate model defect uncertainties are presented, which lead to more reasonable evaluated uncertainties. The calculated keff of selected criticality benchmarks obtained with these new evaluations agree with each other within their uncertainties despite the different approaches to estimate model defect uncertainties. The keff one standard deviations overlap with some of those obtained using ENDF/B-VII.1, albeit their mean values are further away from unity. Spectral indexes for the Jezebel critical assembly calculated with the newly evaluated PFNS agree with the experimental data for selected (n,γ) and (n,f) reactions, and show improvements for high-energy threshold (n,2n) reactions compared to ENDF/B-VII.1.

  10. Evaluating the BD-100R [Bubble Technology Industries] as a neutron spectrometer through pressure variation

    SciTech Connect

    White, B.; Ebert, D.; Munno, F.

    1990-07-01

    Other investigators have evaluated the dose response of neutron bubble dosimeters for possible use as personnel monitors for the U.S. Navy in low level radiation fields. In addition to dose measurements, these devices have been modified to measure the neutron energy spectra. These methods tend to be cumbersome, inaccurate, or both and do not use the same devices as employed in the dosimetry. The BD-100R dosimeter used in this work consists of a test tube containing an elastic polymer with interspersed droplets of two types of Freon; Freon-12 and Freon-114. Each superheated liquid droplet is a potential nucleation site. The minimum energy needed to form a bubble from the nucleation site is given by, E = 16{pi}{gamma}{sup 3}(T)/3({delta}P){sup 2}, where {delta}P is the difference between the vapor pressure of the droplet and the applied pressure. Upon reaching a critical radius, a bubble becomes unstable and grows in size. It may be seen from this equation that the energy deposition required for bubble formation is inversely proportional to the square of the pressure difference. The number of bubbles formed continually decreases with increasing applied pressure, until a pressure is reached where no bubbles are formed since the energy transferred can no longer vaporize the Freon. This investigation is intended to demonstrate the determination of an unknown spectrum utilizing the dosimeter response (number of bubbles formed) as a function of the neutron energy (applied pressure). A set of 12 dosimeters was initially exposed outside the East Beam Port (EBP) at the Maryland University Training Reactor (MUTR). The dosimeters were inside a pressure chamber which could accommodate up to 18 dosimeters. The same set of dosimeters were irradiated using a paraffin moderated PuBe source for which the neutron energy spectrum is unknown. There were eight exposures of six dosimeters at varied pressures in the EBP. The average number of bubbles and standard deviation was measured

  11. Neutronics Evaluation of Lithium-Based Ternary Alloys in IFE Blankets

    SciTech Connect

    Jolodosky, A.; Fratoni, M.

    2014-11-20

    Pre-conceptual fusion blanket designs require research and development to reflect important proposed changes in the design of essential systems, and the new challenges they impose on related fuel cycle systems. One attractive feature of using liquid lithium as the breeder and coolant is that it has very high tritium solubility and results in very low levels of tritium permeation throughout the facility infrastructure. However, lithium metal vigorously reacts with air and water and presents plant safety concerns. If the chemical reactivity of lithium could be overcome, the result would have a profound impact on fusion energy and associated safety basis. The overriding goal of this project is to develop a lithium-based alloy that maintains beneficial properties of lithium (e.g. high tritium breeding and solubility) while reducing overall flammability concerns. To minimize the number of alloy combinations that must be explored, only those alloys that meet certain nuclear performance metrics will be considered for subsequent thermodynamic study. The specific scope of this study is to evaluate the neutronics performance of lithium-based alloys in the blanket of an inertial confinement fusion (ICF) engine. The results of this study will inform the development of lithium alloys that would guarantee acceptable neutronics performance while mitigating the chemical reactivity issues of pure lithium.

  12. ATR LEU Monolithic Foil-Type Fuel with Integral Cladding Burnable Absorber – Neutronics Performance Evaluation

    SciTech Connect

    Gray Chang

    2012-03-01

    The Advanced Test Reactor (ATR), currently operating in the United States, is used for material testing at very high neutron fluxes. Powered with highly enriched uranium (HEU), the ATR has a maximum thermal power rating of 250 MWth. Because of the large test volumes located in high flux areas, the ATR is an ideal candidate for assessing the feasibility of converting HEU driven reactor cores to low-enriched uranium (LEU) cores. The burnable absorber - 10B, was added in the inner and outer plates to reduce the initial excess reactivity, and to improve the peak ratio of the inner/outer heat flux. The present work investigates the LEU Monolithic foil-type fuel with 10B Integral Cladding Burnable Absorber (ICBA) design and evaluates the subsequent neutronics operating effects of this proposed fuel designs. The proposed LEU fuel specification in this work is directly related to both the RERTR LEU Development Program and the Advanced Test Reactor (ATR) LEU Conversion Project at Idaho National Laboratory (INL).

  13. Present status of beryllide R&D as neutron multiplier

    NASA Astrophysics Data System (ADS)

    Kawamura, H.; Takahashi, H.; Yoshida, N.; Mishima, Y.; Ishida, K.; Iwadachi, T.; Cardella, A.; van der Laan, J. G.; Uchida, M.; Munakata, K.; Sato, Y.; Shestakov, V.; Tanaka, S.

    2004-08-01

    Since 1997, beryllide application as the neutron multiplier has been proposed in Japan and preliminary investigations revealed that some beryllides such as Be 12Ti have excellent properties compared with beryllium metal. Recently, several international R&D programs were performed. Some pebbles of modified Be 12Ti that included the Be phase were obtained by the rotating electrode method. Basic characterization using HIPped Be 12Ti has also been performed. Preliminary experiments indicate that compatibility with stainless steel and tritium breeder materials, deuterium release, natural oxidation and oxidations by steam interaction were better than the behavior of beryllium. Preliminary neutron irradiation effects were studied in JMTR and by charged particle irradiation. It was observed that Be 12Ti has less radiation damage than beryllium. In a future experiment, Japanese Be 12Ti samples will be included in a long European irradiation program on beryllium to produce up to 6000 appm He. This is an IEA collaborative experiment, to evaluate neutron irradiation effects.

  14. Grazing incidence neutron optics

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail V. (Inventor); Ramsey, Brian D. (Inventor); Engelhaupt, Darell E. (Inventor)

    2012-01-01

    Neutron optics based on the two-reflection geometries are capable of controlling beams of long wavelength neutrons with low angular divergence. The preferred mirror fabrication technique is a replication process with electroform nickel replication process being preferable. In the preliminary demonstration test an electroform nickel optics gave the neutron current density gain at the focal spot of the mirror at least 8 for neutron wavelengths in the range from 6 to 20 .ANG.. The replication techniques can be also be used to fabricate neutron beam controlling guides.

  15. Grazing Incidence Neutron Optics

    NASA Technical Reports Server (NTRS)

    Gubarev, Mikhail V. (Inventor); Ramsey, Brian D. (Inventor); Engelhaupt, Darell E. (Inventor)

    2013-01-01

    Neutron optics based on the two-reflection geometries are capable of controlling beams of long wavelength neutrons with low angular divergence. The preferred mirror fabrication technique is a replication process with electroform nickel replication process being preferable. In the preliminary demonstration test an electroform nickel optics gave the neutron current density gain at the focal spot of the mirror at least 8 for neutron wavelengths in the range from 6 to 20.ANG.. The replication techniques can be also be used to fabricate neutron beam controlling guides.

  16. Preliminary joint X-ray and neutron protein crystallographic studies of endoxylanase II from the fungus Trichoderma longibrachiatum.

    PubMed

    Kovalevsky, Andrey Y; Hanson, B Leif; Seaver, Sean; Fisher, S Zoë; Mustyakimov, Marat; Langan, Paul

    2011-02-01

    Room-temperature X-ray and neutron diffraction data were measured from a family 11 endoxylanase holoenzyme (XynII) originating from the filamentous fungus Trichoderma longibrachiatum to 1.55 Å resolution using a home source and to 1.80 Å resolution using the Protein Crystallography Station at LANSCE. Crystals of XynII, which is an important enzyme for biofuel production, were grown at pH 8.5 in order to examine the effect of basic conditions on the protonation-state distribution in the active site and throughout the protein molecule and to provide insights for rational engineering of catalytically improved XynII for industrial applications.

  17. Evaluation of an agro--ecosystem model using cosmicray neutron soil moisture

    NASA Astrophysics Data System (ADS)

    Carr, Benjamin David

    The properties of the land surface affect the interaction of the surface and the atmosphere. The partitioning of absorbed shortwave radiation into emitted radiation, sensible heat flux, latent heat flux, and soil heat flux is determined by the presence of soil moisture. When the land surface is dry, there will be higher sensible heat flux, emitted radiation and soil heat flux. However, when liquid water is present, latent energy will be used to change the phase of water from solid to liquid and liquid to gas. This latent heat flux moves water and energy to a different part of the atmosphere. A contributing factor to soil moisture available for latent heat flux is the water table. With a shallow water table (< 5 m), plant roots are able to extract water for growth and generally an increase in latent heat flux is seen. In the Midwest U.S., the management of fields changes the latent heat flux through different crop choices, planting and harvest date, fertilizer application, and tile drainage. Therefore, land surface models, like Agro--IBIS, need to be simulated and evaluated at the field--scale. Agro--IBIS is an agroecosystem model that is able to incorporate changes in vegetation growth as well as management practices, which in turn impact soil moisture available for latent heat flux. Agro--IBIS has been updated with the soil physics of HYDRUS--1D in order to accurately simulate the impact of the water table. In measuring soil moisture, a consistent challenge is the representative scale of the instrument, which is often a point. A newer method of obtaining soil moisture over the field--scale is using a cosmic--ray neutron detector, which is sensitive to a diameter of 700 m and to a depth of ˜ 20 cm. I used soil moisture observed by the cosmic--ray neutron detector in an agricultural field to evaluate estimates made with the Agro--IBIS model over a growing season of maize and a growing season of soybean. Because of the large area observed by the cosmic-ray neutron

  18. Evaluating the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks

    NASA Astrophysics Data System (ADS)

    Ortiz-Rodríguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.; Solís Sánches, L. O.; Miranda, R. Castañeda; Cervantes Viramontes, J. M.; Vega-Carrillo, H. R.

    2013-07-01

    In this work the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks is evaluated. The first one code based on traditional iterative procedures and called Neutron spectrometry and dosimetry from the Universidad Autonoma de Zacatecas (NSDUAZ) use the SPUNIT iterative algorithm and was designed to unfold neutron spectrum and calculate 15 dosimetric quantities and 7 IAEA survey meters. The main feature of this code is the automated selection of the initial guess spectrum trough a compendium of neutron spectrum compiled by the IAEA. The second one code known as Neutron spectrometry and dosimetry with artificial neural networks (NDSann) is a code designed using neural nets technology. The artificial intelligence approach of neural net does not solve mathematical equations. By using the knowledge stored at synaptic weights on a neural net properly trained, the code is capable to unfold neutron spectrum and to simultaneously calculate 15 dosimetric quantities, needing as entrance data, only the rate counts measured with a Bonner spheres system. Similarities of both NSDUAZ and NSDann codes are: they follow the same easy and intuitive user's philosophy and were designed in a graphical interface under the LabVIEW programming environment. Both codes unfold the neutron spectrum expressed in 60 energy bins, calculate 15 dosimetric quantities and generate a full report in HTML format. Differences of these codes are: NSDUAZ code was designed using classical iterative approaches and needs an initial guess spectrum in order to initiate the iterative procedure. In NSDUAZ, a programming routine was designed to calculate 7 IAEA instrument survey meters using the fluence-dose conversion coefficients. NSDann code use artificial neural networks for solving the ill-conditioned equation system of neutron spectrometry problem through synaptic weights of a properly trained neural network. Contrary to iterative procedures, in neural

  19. Evaluating the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks

    SciTech Connect

    Ortiz-Rodriguez, J. M.; Reyes Alfaro, A.; Reyes Haro, A.; Solis Sanches, L. O.; Miranda, R. Castaneda; Cervantes Viramontes, J. M.; Vega-Carrillo, H. R.

    2013-07-03

    In this work the performance of two neutron spectrum unfolding codes based on iterative procedures and artificial neural networks is evaluated. The first one code based on traditional iterative procedures and called Neutron spectrometry and dosimetry from the Universidad Autonoma de Zacatecas (NSDUAZ) use the SPUNIT iterative algorithm and was designed to unfold neutron spectrum and calculate 15 dosimetric quantities and 7 IAEA survey meters. The main feature of this code is the automated selection of the initial guess spectrum trough a compendium of neutron spectrum compiled by the IAEA. The second one code known as Neutron spectrometry and dosimetry with artificial neural networks (NDSann) is a code designed using neural nets technology. The artificial intelligence approach of neural net does not solve mathematical equations. By using the knowledge stored at synaptic weights on a neural net properly trained, the code is capable to unfold neutron spectrum and to simultaneously calculate 15 dosimetric quantities, needing as entrance data, only the rate counts measured with a Bonner spheres system. Similarities of both NSDUAZ and NSDann codes are: they follow the same easy and intuitive user's philosophy and were designed in a graphical interface under the LabVIEW programming environment. Both codes unfold the neutron spectrum expressed in 60 energy bins, calculate 15 dosimetric quantities and generate a full report in HTML format. Differences of these codes are: NSDUAZ code was designed using classical iterative approaches and needs an initial guess spectrum in order to initiate the iterative procedure. In NSDUAZ, a programming routine was designed to calculate 7 IAEA instrument survey meters using the fluence-dose conversion coefficients. NSDann code use artificial neural networks for solving the ill-conditioned equation system of neutron spectrometry problem through synaptic weights of a properly trained neural network. Contrary to iterative procedures, in neural

  20. Preliminary study on quality evaluation of pecans with terahertz time-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Bin; Cao, Wei; Mathanker, Sunil; Zhang, Weili; Wang, Ning

    2010-11-01

    This paper reports a preliminary work on a feasibility study of applying terahertz (THz) technology for pecan quality evaluation. A set of native pecan nuts collected in 2009 were used during the experiment. Each pecan nutmeat was manually sliced at a thickness of about 1mm, 2mm, and 3mm and a size of about 2cm (length) ×1cm (width). Pecan shell and inner separator were also cut into the same size. The absorption spectra for the nutmeat slices, shell, and inner separator were collected using a THz time-domain spectroscopy (THz-TDS) developed by a group of researchers at Oklahoma State University. The test results show that nutmeat, shell, and inner separator had different absorption characteristics within the bandwidth of 0.2-2.0 THz. To study the capability of insect damage detection of the THz spectroscopy, the absorption spectra of insects (living manduca sexta and dry pecan weevil) were also collected. Due to high water contents in the insects, very obvious spectral characteristics were found. The results from the preliminary study show a potential of THz technology applied for quality detection of bio-products. However, since bio-products mostly have high water content and are handled under an environment with certain levels of water content, practical issues needs to be further investigated to make the THz technology a feasible tool for quality evaluation.

  1. Evaluation of neutron flux parameters in irradiation sites of research reactor using the Westcott-formalism for the k0 neutron activation analysis method

    NASA Astrophysics Data System (ADS)

    Kasban, H.; Hamid, Ashraf

    2015-12-01

    Instrumental Neutron Activation Analysis using k0 (k0-INAA) method has been used to determine a number of elements in sediment samples collected from El-Manzala Lake in Egypt. k0-INAA according to Westcott's formalism has been implemented using the complete irradiation kit of the fast pneumatic rabbit and some selected manually loaded irradiation sites for short and long irradiation at Egypt Second Research Reactor (ETRR-2). Zr-Au and Co sets as neutron flux monitors are used to determine the neutron flux parameters (f and α) in each irradiation sites. Two reference materials IAEA Soil-7 samples have been inserted and implemented for data validation and an internal monostandard multi monitor used (k0 based IM-NAA). It was given a good agreement between the experimental analyzed values and that obtained of the certified values. The major and trace elements in the sediment samples have been evaluated with the use of Co as an internal and Au as an external monostandard comparators. The concentrations of the elements (Cr, Mn and Zn) in the sediment samples of the present work are discussed regarding to those obtained from other sites.

  2. Unified Monte Carlo: Evaluation, Uncertainty Quantification and Propagation of the Prompt Fission Neutron Spectrum

    NASA Astrophysics Data System (ADS)

    Rising, Michael E.; Talou, Patrick; Prinja, Anil K.; White, Morgan C.

    2014-06-01

    The unified Monte Carlo (UMC) method is used for the quantification of uncertainties associated with the evaluation of the prompt fission neutron spectrum (PFNS) for the n(0.5 MeV)+239Pu fission reaction and compared to the Kalman filter. Ultimately, the UMC and Kalman filter approaches lead to very similar evaluated PFNS while UMC is also capable of capturing the nonlinearities present in the Los Alamos (LA) model used to calculate the PFNS. Next, the unified Monte Carlo + total Monte Carlo (UMC+TMC) method is implemented to propagate uncertainties from the prior LA model parameters through the Flattop critical assemblies. Due to the fact that cross-experiment correlations are neglected in the present evaluation work, the UMC+TMC method predicts uncertainties in the integral quantities smaller by an order of magnitude or more compared to direct sampling from the posterior LA model parameters. Last, the UMC method is proposed for use as an evaluation tool that can be used with the new prompt fission Monte Carlo Hauser-Feshbach codes that are currently under development.

  3. Comparisons of Neutron Cross Sections and Isotopic Composition Calculations for Fission-Product Evaluations

    NASA Astrophysics Data System (ADS)

    Kim, Do Heon; Gil, Choong-Sup; Chang, Jonghwa; Lee, Yong-Deok

    2005-05-01

    The neutron absorption cross sections for 18 fission products evaluated within the framework of the KAERI (Korea Atomic Energy Research Institute)-BNL (Brookhaven National Laboratory) international collaboration have been compared with ENDF/B-VI.7. Also, the influence of the new evaluations on the isotopic composition calculations of the fission products has been estimated through the OECD/NEA burnup credit criticality benchmarks (Phase 1B) and the LWR/Pu recycling benchmarks. These calculations were performed by WIMSD-5B with the 69-group libraries prepared from three evaluated nuclear data libraries: ENDF/B-VI.7, ENDF/B-VI.8 including the new evaluations in the resonance region covering the thermal region, and the expected ENDF/B-VII including those in the upper resonance region up to 20 MeV. For Xe-131, the composition calculated with ENDF/B-VI.8 shows a maximum difference of 5.02% compared to ENDF/B-VI.7. However, the isotopic compositions of all the fission products calculated with the expected ENDF/B-VII show no differences when compared to ENDF/B-VI.7 for the thermal reactor benchmark cases.

  4. Preliminary evaluation of space station transmission line in a ring configuration

    NASA Technical Reports Server (NTRS)

    Roth, Mary Ellen

    1990-01-01

    The results of a preliminary evaluation of a space station type transmission line and commercial transmission lines in a ring configuration, are reported. In a ring configuration, each node has two paths for the return current of each wire. The additional path can create an unbalanced condition, where the magnetic fields created by the forward and return currents do not cancel. This evaluation was to quantify the effects of the unbalanced case upon the external fields. The transmission lines evaluated were standard commercial coaxial cables, RG59 and RG213, and a space station designed flat Litz transmission line. Each was evaluated in a balanced and unbalanced mode of operation. Currents and their harmonic content were recorded and compared. As expected, the harmonic content of the different current (I delta) was substantial for the unbalanced case as compared to the balanced case. For the balanced case, very little difference was noted among the various transmission lines evaluated. The evaluation is discussed, and the test circuit, the measurements, and the resulting data are described.

  5. HACCP and water safety plans in Icelandic water supply: preliminary evaluation of experience.

    PubMed

    Gunnarsdóttir, María J; Gissurarson, Loftur R

    2008-09-01

    Icelandic waterworks first began implementing hazard analysis and critical control points (HACCP) as a preventive approach for water safety management in 1997. Since then implementation has been ongoing and currently about 68% of the Icelandic population enjoy drinking water from waterworks with a water safety plan based on HACCP. Preliminary evaluation of the success of HACCP implementation was undertaken in association with some of the waterworks that had implemented HACCP. The evaluation revealed that compliance with drinking water quality standards improved considerably following the implementation of HACCP. In response to their findings, waterworks implemented a large number of corrective actions to improve water safety. The study revealed some limitations for some, but not all, waterworks in relation to inadequate external and internal auditing and a lack of oversight by health authorities. Future studies should entail a more comprehensive study of the experience with the use of HACCP with the purpose of developing tools to promote continuing success.

  6. Development of the wireless ultra-miniaturized inertial measurement unit WB-4: preliminary performance evaluation.

    PubMed

    Lin, Zhuohua; Zecca, Massimiliano; Sessa, Salvatore; Bartolomeo, Luca; Ishii, Hiroyuki; Takanishi, Atsuo

    2011-01-01

    This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized inertial measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated.

  7. Development of the wireless ultra-miniaturized inertial measurement unit WB-4: preliminary performance evaluation.

    PubMed

    Lin, Zhuohua; Zecca, Massimiliano; Sessa, Salvatore; Bartolomeo, Luca; Ishii, Hiroyuki; Takanishi, Atsuo

    2011-01-01

    This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized inertial measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated. PMID:22255931

  8. Evaluation of {sup 28,29,30}Si neutron induced cross sections for ENDF/B-VI

    SciTech Connect

    Hetrick, D.M.; Larson, D.C.; Larson, N.M.; Leal, L.C.; Epperson, S.J.

    1997-04-01

    Separate evaluations have been done for the three stable isotopes of silicon for ENDF/B-VI. The evaluations are based on analysis of experimental data, supplemented by results of nuclear model calculations. The computational methods and the parameters required as input to the nuclear model codes are reviewed. Discussion of the evaluated data given for resonance parameters, neutron induced reaction cross sections, associated angular and energy distributions, and gamma-ray production cross sections is included. Extensive comparisons of the evaluated cross sections to measured data are shown in this report. The evaluations include all necessary data to allow KERMA (Kinetic Energy Released in MAterials) and displacement cross sections to be calculated directly. These quantities are fundamental to studies of neutron heating and radiation damage.

  9. Preliminary Benchmark Evaluation of Japan’s High Temperature Engineering Test Reactor

    SciTech Connect

    John Darrell Bess

    2009-05-01

    A benchmark model of the initial fully-loaded start-up core critical of Japan’s High Temperature Engineering Test Reactor (HTTR) was developed to provide data in support of ongoing validation efforts of the Very High Temperature Reactor Program using publicly available resources. The HTTR is a 30 MWt test reactor utilizing graphite moderation, helium coolant, and prismatic TRISO fuel. The benchmark was modeled using MCNP5 with various neutron cross-section libraries. An uncertainty evaluation was performed by perturbing the benchmark model and comparing the resultant eigenvalues. The calculated eigenvalues are approximately 2-3% greater than expected with an uncertainty of ±0.70%. The primary sources of uncertainty are the impurities in the core and reflector graphite. The release of additional HTTR data could effectively reduce the benchmark model uncertainties and bias. Sensitivity of the results to the graphite impurity content might imply that further evaluation of the graphite content could significantly improve calculated results. Proper characterization of graphite for future Next Generation Nuclear Power reactor designs will improve computational modeling capabilities. Current benchmarking activities include evaluation of the annular HTTR cores and assessment of the remaining start-up core physics experiments, including reactivity effects, reactivity coefficient, and reaction-rate distribution measurements. Long term benchmarking goals might include analyses of the hot zero-power critical, rise-to-power tests, and other irradiation, safety, and technical evaluations performed with the HTTR.

  10. Preliminary Assessment of the Nuclide Migration from the Activation Zone Around the Proposed Spallation Neutron Source Facility

    SciTech Connect

    Dole, L.R.

    1998-09-01

    The purpose of this study is to investigate the potential impacts of migrating radionuclides from the activation zone around the proposed Spallation Neutron Source (SNS). Using conservatively high estimates of the potential inventory of radioactive activation products that could form in the proposed compacted-soil shield berm around an SNS facility on the Oak Ridge Reservation (ORR), a conservative, simplified transport model was used to estimate the potential worst-case concentrations of the 12 long-lived isotopes in the groundwater under a site with the hydrologic characteristics of the ORR. Of the 12, only 3 isotopes showed any potential to exceed the U.S. Nuclear Regulatory Commission (NRC) 10 Code of Federal Regulations (CFR) Part 20 Drinking Water Limits (DWLs). These isotopes were 14C, 22Na, and 54Mn. The latter two activation products have very short half-lives of 2.6 years and 0.854 year, respectively. Therefore, these will decay before reaching an off-site receptor, and they cannot pose off-site hazards. However, for this extremely conservative model, which overestimates the mobility of the contaminant, 14C, which has a 5,730-year half-life, was shown to represent a potential concern in the context of this study's conservative assumptions. This study examines alternative modifications to the SNS shield berm and makes recommendations.

  11. R-Matrix Evaluation of {sup 16}O neutron cross sections up to 6.3 MeV

    SciTech Connect

    Sayer, R.O.; Leal, L.C.; Larson, N.M.; Spencer, R.R.; and Wright, R.Q.

    2000-08-01

    In this paper the authors describe an evaluation of {sup 16}O neutron cross sections in the resolved resonance region with the multilevel Reich-Moore R-matrix formalism. Resonance analyses were performed with the computer code SAMMY [LA98] which utilizes Bayes' method, a generalized least squares technique.

  12. In-plant test and evaluation of the neutron collar for verification of PWR fuel assemblies at Resende, Brazil

    SciTech Connect

    Menlove, H.O.; Marzo, M.A.S.; de Almeida, S.G.; de Almeida, M.C.; Moitta, L.P.M.; Conti, L.F.; de Paiva, J.R.T.

    1985-11-01

    The neutron-coincidence collar has been evaluated for the measurement of pressurized-water reactor (PWR) fuel assemblies at the Fabrica de Elementos Combustiveis plant in Resende, Brazil. This evaluation was part of the cooperative-bilateral-safeguards technical-exchange program between the United States and Brazil. The neutron collar measures the STVU content per unit length of full fuel assemblies using neutron interrogation and coincidence counting. The STYU content is measured in the passive mode without the AmLi neutron-interrogation source. The extended evaluation took place over a period of 6 months with both scanning and single-zone measurements. The results of the tests gave a coincidence-response standard deviation of 0.7% (sigma = 1.49% for mass) for the active case and 2.5% for the passive case in 1000-s measurement times. The length measurement in the scanning mode was accurate to 0.77%. The accuracies of different calibration methods were evaluated and compared.

  13. Preliminary evaluation of alternative waste form solidification processes. Volume II. Evaluation of the processes

    SciTech Connect

    Not Available

    1980-08-01

    This Volume II presents engineering feasibility evaluations of the eleven processes for solidification of nuclear high-level liquid wastes (HHLW) described in Volume I of this report. Each evaluation was based in a systematic assessment of the process in respect to six principal evaluation criteria: complexity of process; state of development; safety; process requirements; development work required; and facility requirements. The principal criteria were further subdivided into a total of 22 subcriteria, each of which was assigned a weight. Each process was then assigned a figure of merit, on a scale of 1 to 10, for each of the subcriteria. A total rating was obtained for each process by summing the products of the subcriteria ratings and the subcriteria weights. The evaluations were based on the process descriptions presented in Volume I of this report, supplemented by information obtained from the literature, including publications by the originators of the various processes. Waste form properties were, in general, not evaluated. This document describes the approach which was taken, the developent and application of the rating criteria and subcriteria, and the evaluation results. A series of appendices set forth summary descriptions of the processes and the ratings, together with the complete numerical ratings assigned; two appendices present further technical details on the rating process.

  14. Covariances Obtained from an Evaluation of the Neutron Cross Section Standards

    SciTech Connect

    Carlson, A.D. Badikov, S.A.; Chen, Zhenpeng; Gai, E.; Hale, G.M.; Hambsch, F.-J.; Hofmann, H.M.; Kawano, T.; Larson, N.M.; Oh, S.Y.; Pronyaev, V.G.; Smith, D.L.; Tagesen, S.; Vonach, H.

    2008-12-15

    New measurements and an improved evaluation process were used to obtain a new evaluation of the neutron cross section standards. Efforts were made to include as much information as possible on the components of the data uncertainties that were then used to obtain the covariance matrices for the experimental data. Evaluations were produced from this process for the {sup 6}Li(n,t), {sup 10}B(n,{alpha}), {sup 10}B(n,{alpha}{sub 1}{gamma}), {sup 197}Au(n,{gamma}), {sup 235}U(n,f), and {sup 238}U(n,f) standard cross sections as well as the non-standard {sup 6}Li(n,n), {sup 10}B(n,n), {sup 238}U(n,{gamma}) and {sup 239}Pu(n,f) cross sections. There is a general increase in the cross sections for most of the new evaluations, by as much as about 5%, compared with the ENDF/B-VI results. Covariance data were obtained for the {sup 6}Li(n,t), {sup 6}Li(n,n), {sup 10}B(n,{alpha}), {sup 10}B(n,{alpha}{sub 1}{gamma}), {sup 10}B(n,n), {sup 197}Au(n,{gamma}), {sup 235}U(n,f), {sup 238}U(n,f), {sup 238}U(n,{gamma}) and {sup 239}Pu(n,f) reactions. Also an independent R-Matrix evaluation was produced for the H(n,n) standard cross-section, however, covariance data are not available for this reaction. The evaluations were used in the new ENDF/B-VII library.

  15. Evaluating outcomes of palliative photodynamic therapy: instrument development and preliminary results

    NASA Astrophysics Data System (ADS)

    Goodell, Teresa T.; Bargo, Paulo R.; Jacques, Steven L.

    2002-06-01

    Background: Subjective measures are considered the gold standard in palliative care evaluation, but no studies have evaluated palliative photodynamic therapy (PDT) subjectively. If PDT is to be accepted as a palliative therapy for later-stage obstructing esophageal and lung cancer, evidence of its effectiveness and acceptability to patients must be made known. Study Design/Materials and Methods: This ongoing study's major aim is to evaluate subjective outcomes of PDT in patients with obstructing esophageal and lung cancer. Existing measures of health status, dysphagia and performance status were supplemented with an instrument developed to evaluate PDT symptom relief and side effect burden, the PDT Side Effects Survey (PSES). Results: PDT patients treated with porfimer sodium (Photofrin) and 630-nm light experienced reduced dysphagia grade and stable performance status for at least one month after PDT (N= 10-17), but these effects did not necessarily persist at three months. Fatigue, appetite and quality of life may be the most burdensome issues for these patients. Conclusions: Preliminary data suggest that the PSES is an acceptable and valid tool for measuring subjective outcomes of palliative PDT. This study is the first attempt to systematically evaluate subjective outcomes of palliative PDT. Multi-center outcomes research is needed to draw generalizable conclusions that will establish PDT's effectiveness in actual clinical practice and enhance the wider adoption of PDT as a cancer symptom relief modality.

  16. Evaluation of dose equivalent by the electronic personal dosemeter for neutron 'Saphydose-N' at different workplaces of nuclear facilities.

    PubMed

    Chau, Q; Lahaye, T

    2007-01-01

    This paper presents the results of measurements made with the electronic personal neutron Saphydose-N during the four campaigns of the European contract EVIDOS (EValuation of Individual DOSimetry in mixed neutron and photon radiation fields). These measurements were performed at Institute for Radiological Protection and Nuclear Safety (IRSN) in France (C0), at the Krümmel Nuclear Power Plant in Germany (C1), at the VENUS Research Reactor and the Belgonucléaire fuel processing plant in Belgium (C2) and at the Ringhals Nuclear Power Plant in Sweden (C3). The results for Saphydose-N are compared with reference values for dose equivalent.

  17. Experimental Evaluation of Neutron Induced Noise on Gated X-ray Framing Cameras

    SciTech Connect

    Izumi, N; Stone, G; Hagmann, C; Sorce, C; Bradley, D K; Moran, M; Landen, O L; Stoeffl, W; Springer, P; Tommasini, R; Hermann, H W; Kyrala, G A; Glebov, V Y; Sangster, T C; Koch, J A

    2009-10-08

    A micro-channel plate based temporally-gated x-ray camera (framing camera) is one of the most versatile diagnostic tools of inertial confinement fusion experiments; particularly for observation of the shape of x-ray self emission from compressed core of imploded capsules. However, components used in an x-ray framing camera have sensitivity to neutrons induced secondary radiations. On early low-yield capsule implosions at the National Ignition Facility (NIF), the expected neutron production is about 5 x 10{sup 14}. Therefore, the expected neutron fluence at a framing camera located {approx} 150 cm from the object is 2 x 10{sup 9} neutrons/cm{sup 2}. To obtain gated x-ray images in such harsh neutron environments, quantitative understanding of neutron-induced backgrounds is crucial.

  18. A Preliminary Evaluation of Fast ForWord-Language as an Adjuvant Treatment in Language Intervention

    PubMed Central

    Fey, Marc E.; Finestack, Lizbeth H.; Gajewski, Byron J.; Popescu, Mihai; Lewine, Jeffrey D.

    2010-01-01

    Purpose Fast ForWord-Language (FFW-L) is designed to enhance children's processing of auditory–verbal signals and, thus, their ability to learn language. As a preliminary evaluation of this claim, we examined the effects of a 5-week course of FFW-L as an adjuvant treatment with a subsequent 5-week conventional narrative-based language intervention (NBLI) that targeted narrative comprehension and production and grammatical output. Method Twenty-three children 6–8 years of age with language impairments were assigned randomly to 1 of 3 intervention sequences: (a) FFW-L/NBLI, (b) NBLI/FFW-L, or (c) wait/NBLI. We predicted that after both treatment periods, the FFW-L/NBLI group would show greater gains on measures of narrative ability, conversational grammar, and nonword repetition than the other groups. Results After the first 5-week study period, the intervention groups, taken together (i.e., FFW-L/NBLI and NBLI/FFW-L), significantly outperformed the no-treatment wait/NBLI group on 2 narrative measures. At the final test period, all 3 groups displayed significant time-related effects on measures of narrative ability, but there were no statistically significant between-groups effects of intervention sequence. Conclusions This preliminary study provides no evidence to support the claim that FFW-L enhances children's response to a conventional language intervention. PMID:19696435

  19. Pilot Implementation and Preliminary Evaluation of START:AV Assessments in Secure Juvenile Correctional Facilities.

    PubMed

    Desmarais, Sarah L; Sellers, Brian G; Viljoen, Jodi L; Cruise, Keith R; Nicholls, Tonia L; Dvoskin, Joel A

    2012-01-01

    The Short-Term Assessment of Risk and Treatability: Adolescent Version (START:AV) is a new structured professional judgment guide for assessing short-term risks in adolescents. The scheme may be distinguished from other youth risk assessment and treatment planning instruments by its inclusion of 23 dynamic factors that are each rated for both vulnerability and strength. In addition, START:AV is also unique in that it focuses on multiple adverse outcomes-namely, violence, self-harm, suicide, unauthorized leave, substance abuse, self-neglect, victimization, and general offending-over the short-term (i.e., weeks to months) rather than long-term (i.e., years). This paper describes a pilot implementation and preliminary evaluation of START:AV in three secure juvenile correctional facilities in the southern United States. Specifically, we examined the descriptive characteristics and psychometric properties of START:AV assessments completed by 21 case managers on 291 adolescent offenders (250 boys and 41 girls) at the time of admission. Results provide preliminary support for the feasibility of completing START:AV assessments as part of routine practice. Findings also highlight differences in the characteristics of START:AV assessments for boys and girls and differential associations between the eight START:AV risk domains. Though results are promising, further research is needed to establish the reliability and validity of START:AV assessments completed in the field. PMID:23316116

  20. Neutron metrology laboratory facility simulation.

    PubMed

    Pereira, Mariana; Salgado, Ana P; Filho, Aidano S; Pereira, Walsan W; Patrão, Karla C S; Fonseca, Evaldo S

    2014-10-01

    The Neutron Low Scattering Laboratory in Brazil has been completely rebuilt. Evaluation of air attenuation parameters and neutron component scattering in the room was done using Monte Carlo simulation code. Neutron fields produced by referenced neutron source were used to calculate neutron scattering and air attenuation.

  1. Neutron metrology laboratory facility simulation.

    PubMed

    Pereira, Mariana; Salgado, Ana P; Filho, Aidano S; Pereira, Walsan W; Patrão, Karla C S; Fonseca, Evaldo S

    2014-10-01

    The Neutron Low Scattering Laboratory in Brazil has been completely rebuilt. Evaluation of air attenuation parameters and neutron component scattering in the room was done using Monte Carlo simulation code. Neutron fields produced by referenced neutron source were used to calculate neutron scattering and air attenuation. PMID:24864318

  2. Evaluating Preschool Children Knowledge about Healthy Lifestyle: Preliminary Examination of the Healthy Lifestyle Evaluation Instrument

    ERIC Educational Resources Information Center

    Grammatikopoulos, Vasilis; Konstantinidou, Elisavet; Tsigilis, Nikolaos; Zachopoulou, Evridiki; Tsangaridou, Niki; Liukkonen, Jarmo

    2008-01-01

    The aim of this study was to develop an instrument to evaluate the knowledge of preschool children about healthy lifestyle behavior. The innovation was that the instrument was designed to get direct evidence about healthy lifestyle from children aged 4-6 years old. Usually, children knowledge is estimated indirectly (parents, teachers), but the…

  3. Preliminary Evaluation of Alternate Designs for HFIR Low-Enriched Uranium Fuel

    SciTech Connect

    Renfro, David G; Chandler, David; Cook, David Howard; Ilas, Germina; Jain, Prashant K; Valentine, Jennifer R

    2014-11-01

    Engineering design studies of the feasibility of conversion of the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel are ongoing at Oak Ridge National Laboratory (ORNL) as part of an effort sponsored by the U.S. Department of Energy s Global Threat Reduction Initiative (GTRI)/Reduced Enrichment for Research and Test Reactors (RERTR) program. The fuel type selected by the program for the conversion of the five high-power research reactors in the U.S. that still use HEU fuel is a new U-Mo monolithic fuel. Studies by ORNL have previously indicated that HFIR can be successfully converted using the new fuel provided (1) the reactor power can be increased from 85 MW to 100 MW and (2) the fuel can be fabricated to a specific reference design. Fabrication techniques for the new fuel are under development by the program but are still immature, especially for the complex aspects of the HFIR fuel design. In FY 2012, the program underwent a major shift in focus to emphasize developing and qualifying processes for the fabrication of reliable and affordable LEU fuel. In support of this new focus and in an effort to ensure that the HFIR fuel design is as suitable for reliable fabrication as possible, ORNL undertook the present study to propose and evaluate several alternative design features. These features include (1) eliminating the fuel zone axial contouring in the previous reference design by substituting a permanent neutron absorber in the lower unfueled region of all of the fuel plates, (2) relocating the burnable neutron absorber from the fuel plates of the inner fuel element to the side plates of the inner fuel element (the fuel plates of the outer fuel element do not contain a burnable absorber), (3) relocating the fuel zone inside the fuel plate to be centered on the centerline of the depth of the plate, and (4) reshaping the radial contour of the relocated fuel zone to be symmetric about this centerline. The present

  4. Preliminary Evaluation of Alternate Designs for HFIR Low-Enriched Uranium Fuel

    SciTech Connect

    Renfro, David; Chandler, David; Cook, David; Ilas, Germina; Jain, Prashant; Valentine, Jennifer

    2014-10-30

    Engineering design studies of the feasibility of conversion of the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel are ongoing at Oak Ridge National Laboratory (ORNL) as part of an effort sponsored by the U.S. Department of Energy’s Global Threat Reduction Initiative (GTRI)/Reduced Enrichment for Research and Test Reactors (RERTR) program. The fuel type selected by the program for the conversion of the five high-power research reactors in the U.S. that still use HEU fuel is a new U-Mo monolithic fuel. Studies by ORNL have previously indicated that HFIR can be successfully converted using the new fuel provided (1) the reactor power can be increased from 85 MW to 100 MW and (2) the fuel can be fabricated to a specific reference design. Fabrication techniques for the new fuel are under development by the program but are still immature, especially for the “complex” aspects of the HFIR fuel design. In FY 2012, the program underwent a major shift in focus to emphasize developing and qualifying processes for the fabrication of reliable and affordable LEU fuel. In support of this new focus and in an effort to ensure that the HFIR fuel design is as suitable for reliable fabrication as possible, ORNL undertook the present study to propose and evaluate several alternative design features. These features include (1) eliminating the fuel zone axial contouring in the previous reference design by substituting a permanent neutron absorber in the lower unfueled region of all of the fuel plates, (2) relocating the burnable neutron absorber from the fuel plates of the inner fuel element to the side plates of the inner fuel element (the fuel plates of the outer fuel element do not contain a burnable absorber), (3) relocating the fuel zone inside the fuel plate to be centered on the centerline of the depth of the plate, and (4) reshaping the radial contour of the relocated fuel zone to be symmetric about this centerline. The

  5. Preliminary Evaluation of Atomization Characteristics of Improved Biodiesel for Gas Turbine Application

    NASA Astrophysics Data System (ADS)

    Kumaran, P.; Gopinathan, M.; Razali, N. M.; Kuperjans, Isabel; Hariffin, B.; Hamdan, H.

    2013-06-01

    Biodiesel is one of the clean burning alternative fuels derived from natural resources and animal fats which is promising fuel for gas turbine application. However, inferior properties of biodiesel such as high viscosity, density and surface tension results in inferior atomization and high emission, hence impedes the fuel compatible for gas turbine application and emits slightly higher emission pollutants due to inferior atomization. This research work focuses on preliminary evaluation of the atomization characteristics of derived from Malaysian waste cooking oil which is the physical properties are subsequently improved by a microwave assisted post treatment scheme. The results shows with improvement in physical properties achieved through the post treatment, biodiesel exhibits significantly better atomization characteristics in terms of spray angle, spray length, sauter mean diameter and shorter evaporation time compared to the biodiesel before improvement and fossil diesel.

  6. Preliminary evaluation of a two-interval, two-alternative infant behavioral testing procedurea)

    PubMed Central

    Browning, Jenna; Buss, Emily; Leibold, Lori J.

    2014-01-01

    The purpose of this study was to evaluate the feasibility and efficiency of an observer-based, two-interval forced-choice infant psychophysical testing procedure. Ten of 11 infants (7–9 months of age) achieved a criterion of 80%-correct detection of a 50-dB sound pressure level noise band in a single testing session. Fewer trials were needed to reach criterion using the two-interval procedure than previously reported for the single-interval observer-based psychophysical procedure [Olsho, Koch, Halpin, and Carter (1987). Devel. Psychol. 23, 627–640]. These results provide preliminary evidence that the two-interval procedure is feasible and efficient while controlling for observer and listener response bias. PMID:25190427

  7. Development and Preliminary Evaluation of a Prototype of a Learning Electronic Medical Record System

    PubMed Central

    King, Andrew J.; Cooper, Gregory F.; Hochheiser, Harry; Clermont, Gilles; Visweswaran, Shyam

    2015-01-01

    Electronic medical records (EMRs) are capturing increasing amounts of data per patient. For clinicians to efficiently and accurately understand a patient’s clinical state, better ways are needed to determine when and how to display EMR data. We built a prototype system that records how physicians view EMR data, which we used to train models that predict which EMR data will be relevant in a given patient. We call this approach a Learning EMR (LEMR). A physician used the prototype to review 59 intensive care unit (ICU) patient cases. We used the data-access patterns from these cases to train logistic regression models that, when evaluated, had AUROC values as high as 0.92 and that averaged 0.73, supporting that the approach is promising. A preliminary usability study identified advantages of the system and a few concerns about implementation. Overall, 3 of 4 ICU physicians were enthusiastic about features of the prototype. PMID:26958296

  8. Preliminary evaluation of the effect of a dynamic preferential runway system upon community noise disturbance

    NASA Technical Reports Server (NTRS)

    Patterson, H. P.; Edmiston, R. P.; Connor, W. K.

    1972-01-01

    A dynamic preferential runway system (DPRS) was developed for John F. Kennedy International Airport for the purpose of controlling short term noise exposure in the neighboring communities. The DPRS is a computer-aided procedure for optimum selection of runways from the standpoint of noise and is based upon a community disturbance model which takes into account flyover levels, size of exposed populations, time of day and week, and persistence of overflights. A preliminary evaluation of the DPRS is presented on the basis of social survey data and telephone complaint records, for the trial period of August and September, 1971. Comparative use is made of data taken in a previous survey of the same community areas in 1969.

  9. Preliminary development and evaluation of an algae-based air regeneration system

    NASA Technical Reports Server (NTRS)

    Nienow, J. A.

    2000-01-01

    The potential of air regeneration system based on the growth of microalgae on the surface of porous ceramic tubes is evaluated. The algae have been maintained in the system for extended periods, up to 360 days. Preliminary measurements of the photosynthetic capacity have been made for Chlorella vulgaris (UTEX 259), Neospongiococcum punctatum (UTEX 786), Stichococcus sp., and Gloeocapsa sp. Under standard test conditions (photosynthetic photon flux approximately 66 micromoles m-2 s-1, initial CO2 concentration approximately 450 micromoles mol-1), mature tubes remove up to 0.2 micromoles of CO2 per tube per minute. The rate of removal increases with photon flux up to at least 225 micromoles m-2 s-1 (PPF); peak rates of 0.35 micromoles of CO2 per tube per minute have been achieved with Chlorella vulgaris. These rates correspond to between 120 and 210 micromoles of CO2 removed per square meter of projected area per minute.

  10. Preliminary Evaluation of MapReduce for High-Performance Climate Data Analysis

    NASA Technical Reports Server (NTRS)

    Duffy, Daniel Q.; Schnase, John L.; Thompson, John H.; Freeman, Shawn M.; Clune, Thomas L.

    2012-01-01

    MapReduce is an approach to high-performance analytics that may be useful to data intensive problems in climate research. It offers an analysis paradigm that uses clusters of computers and combines distributed storage of large data sets with parallel computation. We are particularly interested in the potential of MapReduce to speed up basic operations common to a wide range of analyses. In order to evaluate this potential, we are prototyping a series of canonical MapReduce operations over a test suite of observational and climate simulation datasets. Our initial focus has been on averaging operations over arbitrary spatial and temporal extents within Modern Era Retrospective- Analysis for Research and Applications (MERRA) data. Preliminary results suggest this approach can improve efficiencies within data intensive analytic workflows.

  11. Determination of uranium at trace levels by radiochemical neutron-activation analysis employing radioisotopic yield evaluation.

    PubMed

    Byrne, A R; Benedik, L

    1988-03-01

    Nanogram and picogram quantities of uranium were determined in biological materials by radiochemical neutron-activation analysis. Two different approaches using either (239)U or (239)Np were employed for cross-checking, and the question of negative errors due to incomplete acid dissolution of any possible inorganic (siliceous) fraction was studied. In the first and main approach, radiochemical separation of the short-lived (239)U (23.5 min) nuclide was based on TBP extraction following rapid conventional wet-ashing. Addition of large amounts of uranium carrier (ca. 50 mg) allowed the chemical yield to be evaluated from the gamma spectrum of the isolated fraction by means of the 186 keV peak of (235)U. In the second approach, the longer-lived (239)Np (56.5 hr) daughter was separated by anion-exchange; this nuclide allowed use of lengthier dissolution procedures employing total decomposition with hydrofluoric acid. Nanogram quantities of (237)Np were irradiated simultaneously with the sample and an aliquot of the resulting solution containing (237)Np and (238)Np (51 hr) was added prior to sample destruction, these isotopes serving as carrier and yield tracer, respectively. Results are presented for a series of reference materials. The methodologies and results from the two approaches are discussed and evaluated. PMID:18964488

  12. Preliminary Evaluation of Removing Used Nuclear Fuel From Nine Shutdown Sites

    SciTech Connect

    Maheras, Steven J.; Best, Ralph; Ross, Steven B.; Buxton, Kenneth A.; England, Jeffery L.; McConnell, Paul

    2013-04-30

    The Blue Ribbon Commission on America’s Nuclear Future identified removal of stranded used nuclear fuel at shutdown sites as a priority so that these sites may be completely decommissioned and put to other beneficial uses. In this report, a preliminary evaluation of removing used nuclear fuel from nine shutdown sites was conducted. The shutdown sites included Maine Yankee, Yankee Rowe, Connecticut Yankee, Humboldt Bay, Big Rock Point, Rancho Seco, Trojan, La Crosse, and Zion. At these sites a total of 7649 used nuclear fuel assemblies and a total of 2813.2 metric tons heavy metal (MTHM) of used nuclear fuel are contained in 248 storage canisters. In addition, 11 canisters containing greater-than-Class C (GTCC) low-level radioactive waste are stored at these sites. The evaluation was divided in four components: • characterization of the used nuclear fuel and GTCC low-level radioactive waste inventory at the shutdown sites • an evaluation of the onsite transportation conditions at the shutdown sites • an evaluation of the near-site transportation infrastructure and experience relevant to the shipping of transportation casks containing used nuclear fuel from the shutdown sites • an evaluation of the actions necessary to prepare for and remove used nuclear fuel and GTCC low-level radioactive waste from the shutdown sites. Using these evaluations the authors developed time sequences of activities and time durations for removing the used nuclear fuel and GTCC low-level radioactive waste from a single shutdown site, from three shutdown sites located close to each other, and from all nine shutdown sites.

  13. INITIAL EVALUATION OF A PULSED WHITE SPECTRUM NEUTRON GENERATOR FOR EXPLOSIVE DETECTION

    SciTech Connect

    King, Michael J.; Miller, Gill T.; Reijonen, Jani; Ji, Qing; Andresen, Nord; Gicquel,, Frederic; Kavlas, Taneli; Leung, Ka-Ngo; Kwan, Joe

    2008-06-02

    Successful explosive material detection in luggage and similar sized containers is acritical issue in securing the safety of all airline passengers. Tensor Technology Inc. has recently developed a methodology that will detect explosive compounds with pulsed fast neutron transmission spectroscopy. In this scheme, tritium beams will be used to generate neutrons with a broad energy spectrum as governed by the T(t,2n)4He fission reaction that produces 0-9 MeV neutrons. Lawrence Berkeley National Laboratory (LBNL), in collaboration with Tensor Technology Inc., has designedand fabricated a pulsed white-spectrum neutron source for this application. The specifications of the neutron source are demanding and stringent due to the requirements of high yield and fast pulsing neutron emission, and sealed tube, tritium operation. In a unique co-axial geometry, the ion source uses ten parallel rf induction antennas to externally couple power into a toroidal discharge chamber. There are 20 ion beam extraction slits and 3 concentric electrode rings to shape and accelerate the ion beam into a titanium cone target. Fast neutron pulses are created by using a set ofparallel-plate deflectors switching between +-1500 volts and deflecting the ion beams across a narrow slit. The generator is expected to achieve 5 ns neutron pulses at tritium ion beam energies between 80 - 120 kV. First experiments demonstrated ion source operation and successful beam pulsing.

  14. Synthesis, characterization and biological evaluation of carboranylmethylbenzo[b]acridones as novel agents for boron neutron capture therapy.

    PubMed

    da Silva, A Filipa F; Seixas, Raquel S G R; Silva, Artur M S; Coimbra, Joana; Fernandes, Ana C; Santos, Joana P; Matos, António; Rino, José; Santos, Isabel; Marques, Fernanda

    2014-07-28

    Herein we present the synthesis and characterization of benzo[b]acridin-12(7H)-ones bearing carboranyl moieties and test their biological effectiveness as boron neutron capture therapy (BNCT) agents in cancer treatment. The cellular uptake of these novel compounds into the U87 human glioblastoma cells was evaluated by boron analysis (ICP-MS) and by fluorescence imaging (confocal microscopy). The compounds enter the U87 cells exhibiting a similar profile, i.e., preferential accumulation in the cytoskeleton and membranes and a low cytotoxic activity (IC50 values higher than 200 μM). The cytotoxic activity and cellular morphological alterations after neutron irradiation in the Portuguese Research Reactor (6.6 × 10(7) neutrons cm(-2) s(-1), 1 MW) were evaluated by the MTT assay and by electron microscopy (TEM). Post-neutron irradiation revealed that BNCT has a higher cytotoxic effect on the cells. Accumulation of membranous whorls in the cytoplasm of cells treated with one of the compounds correlates well with the cytotoxic effect induced by radiation. Results provide a strong rationale for considering one of these compounds as a lead candidate for a new generation of BNCT agents.

  15. A preliminary evaluation work on a 3D ultrasound imaging system for 2D array transducer

    NASA Astrophysics Data System (ADS)

    Zhong, Xiaoli; Li, Xu; Yang, Jiali; Li, Chunyu; Song, Junjie; Ding, Mingyue; Yuchi, Ming

    2016-04-01

    This paper presents a preliminary evaluation work on a pre-designed 3-D ultrasound imaging system. The system mainly consists of four parts, a 7.5MHz, 24×24 2-D array transducer, the transmit/receive circuit, power supply, data acquisition and real-time imaging module. The row-column addressing scheme is adopted for the transducer fabrication, which greatly reduces the number of active channels . The element area of the transducer is 4.6mm by 4.6mm. Four kinds of tests were carried out to evaluate the imaging performance, including the penetration depth range, axial and lateral resolution, positioning accuracy and 3-D imaging frame rate. Several strong reflection metal objects , fixed in a water tank, were selected for the purpose of imaging due to a low signal-to-noise ratio of the transducer. The distance between the transducer and the tested objects , the thickness of aluminum, and the seam width of the aluminum sheet were measured by a calibrated micrometer to evaluate the penetration depth, the axial and lateral resolution, respectively. The experiment al results showed that the imaging penetration depth range was from 1.0cm to 6.2cm, the axial and lateral resolution were 0.32mm and 1.37mm respectively, the imaging speed was up to 27 frames per second and the positioning accuracy was 9.2%.

  16. Informationist programme in support of biomedical research: a programme description and preliminary findings of an evaluation

    PubMed Central

    Whitmore, Susan C.; Grefsheim, Suzanne F.; Rankin, Jocelyn A.

    2008-01-01

    Background The informationist programme at the Library of the National Institutes of Health (NIH) in Bethesda, MD, USA has grown to 14 informationists working with 40 clinical and basic science research teams. Purpose This case report, intended to contribute to the literature on informationist programmes, describes the NIH informationist programme including implementation experiences, the informationists' training programme, their job responsibilities and programme outcomes. Brief description The NIH informationist programme was designed to enhance the library's service capacity. Over time, the steps for introducing the service to new groups were formalized to ensure support by leadership, the team being served and the library. Job responsibilities also evolved from traditional library roles to a wide range of knowledge management activities. The commitment by the informationist, the team and the library to continuous learning is critical to the programme's success. Results/outcomes NIH scientists reported that informationists saved them time and contributed to teamwork with expert searching and point-of-need instruction. Process evaluation helped refine the programme. Evaluation method High-level, preliminary outcomes were identified from a survey of scientists receiving informationist services, along with key informant interviews. Process evaluation examined service implementation, informationists' training, and service components. Anecdotal evidence has also indicated a favorable response to the programme. PMID:18494648

  17. Preliminary evaluation of crisis-relocation fallout-shelter options. Volume 2. Detailed analysis

    SciTech Connect

    Santini, D.J.; Clinch, J.M.; Davis, F.H.; Hill, L.G.; Lynch, E.P.; Tanzman, E.A.; Wernette, D.R.

    1982-12-01

    This report presents a preliminary, detailed evaluation of various shelter options for use if the President orders crisis relocation of the US urban population because of strong expectation of a nuclear war. The availability of livable shelter space at 40 ft/sup 2/ per person (congregate-care space) by state is evaluated. Options are evaluated for construction of fallout shelters allowing 10 ft/sup 2/ per person - such shelters are designed to provide 100% survival at projected levels of radioactive fallout. The FEMA concept of upgrading existing buildings to act as fallout shelters can, in principle, provide adequate shelter throughout most of the US. Exceptions are noted and remedies proposed. In terms of upgrading existing buildings to fallout shelter status, great benefits are possible by turning away from a standard national approach and adopting a more site-specific approach. Existing FEMA research provides a solid foundation for successful crisis relocation planning, but the program can be refined by making suitable modifications in its locational, engineering, and institutionally specific elements.

  18. DEMONSTRATION OF FUEL CELLS TO RECOVER ENERGY FROM ANAEROBIC DIGESTER GAS - PHASE I. CONCEPTUAL DESIGN, PRELIMINARY COST, AND EVALUATION STUDY

    EPA Science Inventory

    The report discusses Phase I (a conceptual design, preliminary cost, and evaluation study) of a program to demonstrate the recovery of energy from waste methane produced by anaerobic digestion of waste water treatment sludge. The fuel cell is being used for this application becau...

  19. Treatment Integrity Assessment of a Daily Report Card Intervention: A Preliminary Evaluation of Two Methods and Frequencies

    ERIC Educational Resources Information Center

    Sanetti, Lisa M. Hagermoser; Chafouleas, Sandra M.; O'Keeffe, Breda V.; Kilgus, Stephen P.

    2013-01-01

    Although intuitively appealing, teacher self-report of treatment integrity is not currently recommended as a method for collecting treatment integrity data. Education researchers have not, however, evaluated features of a treatment integrity self-reporting system that may facilitate accurate self-report. In this preliminary investigation, four…

  20. Preliminary Evaluation of Commercial Off the Shelf (COTS) Packing Materials for Flight Medication Dispenser (FMD) Technology Development

    NASA Technical Reports Server (NTRS)

    Du, B.; Daniels, V.; Crady, C.; Putcha, L.

    2011-01-01

    This slide presentation reviews preliminary results of the program to evaluate Commercial Off the Shelf (COTS) packaging materials for pharmaceutical stability. The need for improved packaging is due to possible changes in chemical and/or physical properties of the drugs, which cause reported reduced potency and/or altered bioavailability and decreased efficacy.

  1. Searching for Gravitational Waves from Unknown Galactic Neutron Stars - Evaluation of the PowerFlux Pipeline

    NASA Astrophysics Data System (ADS)

    Sauter, Orion; Riles, Keith; Dergachev, Vladimir

    2016-03-01

    Isolated rotating neutron stars with significant non-axisymmetry can emit gravitational radiation of nearly constant frequency and amplitude. Because the resulting amplitudes are expected to be extremely weak, long time integrations must be carried out to detect a signal. This task is made difficult in all-sky searches for unknown galactic stars by the motion of the Earth (daily rotation and orbital motion) which induces substantial, location-dependent modulations of detected frequency and amplitude. Several software pipelines have been developed to search for such signals in recent data from Advanced LIGO. An evaluation of the performances of these pipelines in data containing instrumental artifacts has been carried out in a mock data challenge, using software injections in Initial LIGO data, We present here the performance of the PowerFlux search program in a search band of 40-2000 Hz, including detection of ``blind'' injections. The program uses a multi-stage hierarchical algorithm, based on semi-coherent and loosely coherent power sums. Results indicate that PowerFlux is well suited to analysis of Advanced LIGO data.

  2. Experimental evaluation of boron neutron capture therapy of human breast carcinoma implanted on nude mice

    NASA Astrophysics Data System (ADS)

    Bose, Satya Ranjan

    2000-06-01

    An in-pool small animal irradiation neutron tube (SAINT) facility was designed, constructed and installed at the University of Virginia Nuclear Research Reactor (UVAR). Thermal neutron flux profiles were measured by foil activation analysis (gold) and verified with DORT and MCNP computer code models. The gamma-ray absorbed dose in the neutron-gamma mixed field was determined from TLD measurements. The SAINT thermal neutron flux was used to investigate the well characterized human breast cancer cell line MCF-7B on both in-vitro samples and in- vivo animal subjects. Boronophenylalanine (BPA enriched in 95% 10B) was used as a neutron capturing agent. The in-vitro response of MCF-7B human breast carcinoma cells to BPA in a mixed field of neutron-gamma radiation or pure 60Co gamma radiation was investigated. The best result (lowest surviving fraction) was observed in cell cultures pre-incubated with BPA and given the neutron irradiation. The least effective treatment consisted of 60Co irradiation only. Immunologically deficient nude mice were inoculated subcutaneously with human breast cancer MCF-7B cells and estradiol pellets (to support tumor growth). The tumor volume in the mouse control group increased over time, as expected. The group of mice exposed only to neutron treatment exhibited initial tumor volume reduction lasting until 35 days following the treatment, followed by renewed tumor growth. Both groups given BPA plus neutron treatment showed continuous reduction in tumor volume over the 55-day observation period. The group given the higher BPA concentration showed the best tumor reduction response. The results on both in-vitro and in-vivo studies showed increased cell killing with BPA, substantiating the incorporation of BPA into the tumor or cell line. Therefore, BNCT may be a possible choice for the treatment of human breast carcinoma. However, prior to the initiation of any clinical studies, it is necessary to determine the therapeutic efficacy in a large

  3. Neutron Cross Section Processing Methods for Improved Integral Benchmarking of Unresolved Resonance Region Evaluations

    NASA Astrophysics Data System (ADS)

    Walsh, Jonathan A.; Forget, Benoit; Smith, Kord S.; Brown, Forrest B.

    2016-03-01

    In this work we describe the development and application of computational methods for processing neutron cross section data in the unresolved resonance region (URR). These methods are integrated with a continuous-energy Monte Carlo neutron transport code, thereby enabling their use in high-fidelity analyses. Enhanced understanding of the effects of URR evaluation representations on calculated results is then obtained through utilization of the methods in Monte Carlo integral benchmark simulations of fast spectrum critical assemblies. First, we present a so-called on-the-fly (OTF) method for calculating and Doppler broadening URR cross sections. This method proceeds directly from ENDF-6 average unresolved resonance parameters and, thus, eliminates any need for a probability table generation pre-processing step in which tables are constructed at several energies for all desired temperatures. Significant memory reduction may be realized with the OTF method relative to a probability table treatment if many temperatures are needed. Next, we examine the effects of using a multi-level resonance formalism for resonance reconstruction in the URR. A comparison of results obtained by using the same stochastically-generated realization of resonance parameters in both the single-level Breit-Wigner (SLBW) and multi-level Breit-Wigner (MLBW) formalisms allows for the quantification of level-level interference effects on integrated tallies such as keff and energy group reaction rates. Though, as is well-known, cross section values at any given incident energy may differ significantly between single-level and multi-level formulations, the observed effects on integral results are minimal in this investigation. Finally, we demonstrate the calculation of true expected values, and the statistical spread of those values, through independent Monte Carlo simulations, each using an independent realization of URR cross section structure throughout. It is observed that both probability table

  4. Description and evaluation of nuclear masses based on residual proton-neutron interactions

    SciTech Connect

    Fu, G. J.; Lei, Y.; Jiang, H.; Zhao, Y. M.; Sun, B.; Arima, A.

    2011-09-15

    In this paper we study the residual proton-neutron interactions and make use of the systematics of these interactions to describe experimental data of nuclear masses and to predict some of the unknown masses. The odd-even effect staggering of the residual proton-neutron interaction between the last proton and the last neutron is found and argued in terms of pairing interactions. Two local mass relations, which work very accurately for masses of four neighboring nuclei, are discovered. The accuracy of our predicted masses for medium and heavy nuclei is competitive with that of the AME2003 extrapolations, with the virtue of simplicity.

  5. Collinear Cluster Tripartition as a Neutron Source--Evaluation of the Setup Parameters

    SciTech Connect

    Kamanin, D. V.; Kuznetsova, E. A.; Aleksandrov, A. A.; Aleksandrova, I. A.; Borzakov, S. B.; Chelnokov, M. L.; Pham Minh, D.; Kondratyev, N. A.; Kopach, Yu. N.; Panteleev, Ts.; Penionzhkevich, Yu. E.; Svirikhin, A. I.; Sokol, E. A.; Testov, D. A.; Zhuchko, V. E.; Yeremin, A. V.; Pyatkov, Yu. V.; Jacobs, N.; Ryabov, Yu. V.

    2010-04-30

    Forthcoming experiments aimed at studying the mechanism of collinear cluster tripartition are planning to be performed with the new facility. Charged products will be registered with the double arm time-of-flight spectrometer composed of mosaics of PIN -diodes and MCP (micro channel plates) based timing detectors. Several tens of {sup 3}He-filled counters will be gathered round the {sup 252}Cf source. In order to choose an optimal configuration of the neutron detector and other parameters of the experiment special modeling has performed using both 'neutron barrel' and known MCNP code. The first test run of the new facility is in progress also its 'neutron skin' in under construction.

  6. Pineapple juice as a negative oral contrast agent in magnetic resonance cholangiopancreatography: a preliminary evaluation.

    PubMed

    Riordan, R D; Khonsari, M; Jeffries, J; Maskell, G F; Cook, P G

    2004-12-01

    The quality of magnetic resonance cholangiopancreatography (MRCP) images is frequently degraded by high signal from the gastrointestinal tract. The aim of this study is to evaluate pineapple juice (PJ) as an oral negative contrast agent in MRCP. Preliminary in vitro evaluation demonstrated that PJ shortened T(2) relaxation time and hence decreased T(2) signal intensity on a standard MRCP sequence to a similar degree to a commercially available negative contrast agent (ferumoxsil). Electrothermal atomic absorption spectrometry assay demonstrated a high manganese concentration in PJ of 2.76 mg dl(-1), which is likely to be responsible for its T(2) imaging properties. MRCP was subsequently performed in 10 healthy volunteers, before and at 15 min and 30 min following ingestion of 400 ml of PJ. Images were assessed blindly by two Consultant Radiologists using a standard grading technique based on contrast effect (degree of suppression of bowel signal), and image effect (diagnostic quality). There were statistically significant improvements in contrast and image effect between pre and post PJ images. There was particularly significant improvement in visualization of the pancreatic duct, but no significant difference between 15 min and 30 min post PJ images. Visualization of the ampulla, common bile duct, common hepatic and central intrahepatic ducts were also significantly improved at 15 min following PJ. Our results demonstrate that PJ, may be used as an alternative to commercially available negative oral contrast agent in MRCP.

  7. Outcome measures to evaluate new technology for tonsillectomy: preliminary experience with Coblation

    NASA Astrophysics Data System (ADS)

    Shah, Udayan K.; Puchalski, Robert; Briggs, Marianne; Chiavacci, Rosetta; Galinkin, Jeffrey

    2001-05-01

    Evaluating the benefits of new surgical technologies does not end with the observation of successful instrument-to- tissue interaction. The impact of new technologies in medicine today is also gauged by improvements in patients' daily activities and performance. We present our outcomes assessment tool for judging the value of applying a novel tonsillectomy technique, plasma- mediated ablation using Coblation technology. Plasma- mediated ablation (PMA) achieves soft tissue resection in the oropharynx by energizing protons to break bonds. Less heat is released, allowing for less thermal injury, and possibly less pain, than with tonsillectomy performed using electrocautery alone. Children undergoing tonsillectomy by PMA, were evaluated using our outcomes-based scale, which asked families to report the degree of interruption of normal activities for the patient and their family during the post-tonsillectomy recovery period. A preliminary review of several outcomes assessments exemplify the benefits and limitations of this tool. The tracking of valuable data is weighed against the limitations of a short time course relative to the duration of disability, and a poor response rate. Future work aims to improve this data collection tool to allow application to other new technologies in otolaryngology.

  8. Preliminary geothermal evaluation of the Mokapu Peninsula on the Island of Oahu, Hawaii

    SciTech Connect

    Not Available

    1981-08-01

    Preliminary geological, geochemical, and geophysical field surveys have been conducted on Mokapu Peninsula on the island of Oahu in an effort to determine whether sufficient indications of geothermal potential exist within or adjacent to the peninsula to justify further, more detailed, exploratory efforts. An evaluation of existing geologic data as well as recently completed mapping on Mokapu indicate that the peninsula is located on the edge of or immediately adjacent to the inferred caldera of Koolau volcano. Geochemical surveys conducted within and around the Mokapu Peninsula included mercury and radon ground gas surveys as well as a limited evaluation of groundwater chemistry. Groundwater sampling on Mokapu Peninsula was severely restricted due to the absence of wells within the study area and thus water chemistry analyses were limited to the Nuupia fish ponds. Schlumberger resistivity soundings were completed in three locations on the peninsula: KVS1, in the northeast quadrant within the Ulupau crater, KVS2 in the northwest quadrant along the main jet runway, and KVS3 in the southeast along Mokapu Road. KVS1 encountered a relatively high resistivity to a depth of approximately 20 meters below sea level which was underlain by a basement resistivity of about 2 to 3 ohm meters. KVS2 and KVS3 detected similar resistivities of 2 to 3 ohm meters at much shallower depths (approximately equivalent to local sea level) below a thin, moderately resistive layer having an impedance ranging from 15 to 118 ohm meters.

  9. Assessing Mental Imagery to Evaluate Topographical Disorientation: Group Study and Preliminary Normative Data.

    PubMed

    Descloux, Virginie; Maurer, Roland

    2016-01-01

    There is currently no specific neuropsychological test assessing spatial orientation abilities, despite the fact that navigational deficits are heavily incapacitating in daily life. This lack of a specific test is probably due to theoretical vagueness of concepts in this field and important interindividual differences in spatial cognition. Here we propose a new standardized test assessing a fundamental component of spatial orientation-namely, mental imagery: Adequate mental visualization of the environment is indeed a necessary step in finding one's way. Two conditions of mental imagery were proposed to a group of 58 patients with a right cerebral lesion and to a control group (N = 117). The 1st condition assessed global, categorical imagery; the 2nd evaluated precise, metric imagery. We evaluated performance of the 2 groups in the 2 conditions and the impact of sociodemographic variables (age, gender, education). Results show that the right-lesioned patients presented difficulties in mental imagery, especially in the metric condition. Moreover, the data indicate a global impact of age and a milder effect of education on mental imagery abilities. Although sample sizes are sometimes small, preliminary normative data are given; already in the present form, they are usable and informative in assessing mental imagery, and more generally, spatial orientation, in a clinical practice.

  10. The development and preliminary psychometric evaluation of an attachment Implicit Association Task.

    PubMed

    Venta, Amanda; Jardin, Charles; Kalpakci, Allison; Sharp, Carla

    2016-01-01

    The importance of measuring attachment insecurity is underscored by a vast literature tying attachment insecurity to numerous psychological disorders. Self-report measures assess explicit attachment beliefs and experiences, while interview measures, like the Adult Attachment Interview, assess implicit internal working models about the self as worthy of care and others as reliable sources of care. The present study is a preliminary psychometric evaluation of a potentially cost-effective method of assessing implicit internal working models of attachment through the development of an Implicit Association Test (IAT). A racially diverse sample of 104 college females was administered Internet-based versions of three IATs (assessing views of the self, mother, and father) as well as self-report measures of attachment and interpersonal problems. Analyses were conducted to evaluate the (a) internal consistency of each task, (b) correlations among the tasks, (c) concurrent validity, and (d) convergent validity. Adequate internal consistency was noted and correlations among the three IATs were significant. No significant associations were observed between the explicit self-report measures of attachment and the IATs. Two primary areas for future research are discussed. First, future research should utilize an implicit attachment measure alongside an IAT. Second, future research should reevaluate the IAT stimuli used.

  11. The development and preliminary psychometric evaluation of an attachment Implicit Association Task.

    PubMed

    Venta, Amanda; Jardin, Charles; Kalpakci, Allison; Sharp, Carla

    2016-01-01

    The importance of measuring attachment insecurity is underscored by a vast literature tying attachment insecurity to numerous psychological disorders. Self-report measures assess explicit attachment beliefs and experiences, while interview measures, like the Adult Attachment Interview, assess implicit internal working models about the self as worthy of care and others as reliable sources of care. The present study is a preliminary psychometric evaluation of a potentially cost-effective method of assessing implicit internal working models of attachment through the development of an Implicit Association Test (IAT). A racially diverse sample of 104 college females was administered Internet-based versions of three IATs (assessing views of the self, mother, and father) as well as self-report measures of attachment and interpersonal problems. Analyses were conducted to evaluate the (a) internal consistency of each task, (b) correlations among the tasks, (c) concurrent validity, and (d) convergent validity. Adequate internal consistency was noted and correlations among the three IATs were significant. No significant associations were observed between the explicit self-report measures of attachment and the IATs. Two primary areas for future research are discussed. First, future research should utilize an implicit attachment measure alongside an IAT. Second, future research should reevaluate the IAT stimuli used. PMID:27583812

  12. Neutronics Evaluation of Lithium-Based Ternary Alloys in IFE Blankets

    SciTech Connect

    Jolodosky, A.; Fratoni, M.

    2015-09-22

    , low electrical conductivity and therefore low MHD pressure drop, low chemical reactivity, and extremely low tritium inventory; the addition of sodium (FLiNaBe) has been considered because it retains the properties of FliBe but also lowers the melting point. Although many of these blanket concepts are promising, challenges still remain. The limited amount of beryllium available poses a problem for ceramic breeders such as the HCPB. FLiBe and FLiNaBe are highly viscous and have a low thermal conductivity. Lithium lead possesses a poor thermal conductivity which can cause problems in both DCLL and LiPb blankets. Additionally, the tritium permeation from these two blankets into plant components can be a problem and must be reduced. Consequently, Lawrence Livermore National Laboratory (LLNL) is attempting to develop a lithium-based alloy—most likely a ternary alloy—which maintains the beneficial properties of lithium (e.g. high tritium breeding and solubility) while reducing overall flammability concerns for use in the blanket of an inertial fusion energy (IFE) power plant. The LLNL concept employs inertial confinement fusion (ICF) through the use of lasers aimed at an indirect-driven target composed of deuterium-tritium fuel. The fusion driver/target design implements the same physics currently experimented at the National Ignition Facility (NIF). The plant uses lithium in both the primary coolant and blanket; therefore, lithium-related hazards are of primary concern. Although reducing chemical reactivity is the primary motivation for the development of new lithium alloys, the successful candidates will have to guarantee acceptable performance in all their functions. The scope of this study is to evaluate the neutronics performance of a large number of lithium-based alloys in the blanket of the IFE engine and assess their properties upon activation. This manuscript is organized as follows: Section 12 presents the models and methodologies used for the analysis; Section

  13. PWR core design, neutronics evaluation and fuel cycle analysis for thorium-uranium breeding recycle

    SciTech Connect

    Bi, G.; Liu, C.; Si, S.

    2012-07-01

    This paper was focused on core design, neutronics evaluation and fuel cycle analysis for Thorium-Uranium Breeding Recycle in current PWRs, without any major change to the fuel lattice and the core internals, but substituting the UOX pellet with Thorium-based pellet. The fuel cycle analysis indicates that Thorium-Uranium Breeding Recycle is technically feasible in current PWRs. A 4-loop, 193-assembly PWR core utilizing 17 x 17 fuel assemblies (FAs) was taken as the model core. Two mixed cores were investigated respectively loaded with mixed reactor grade Plutonium-Thorium (PuThOX) FAs and mixed reactor grade {sup 233}U-Thorium (U{sub 3}ThOX) FAs on the basis of reference full Uranium oxide (UOX) equilibrium-cycle core. The UOX/PuThOX mixed core consists of 121 UOX FAs and 72 PuThOX FAs. The reactor grade {sup 233}U extracted from burnt PuThOX fuel was used to fabrication of U{sub 3}ThOX for starting Thorium-. Uranium breeding recycle. In UOX/U{sub 3}ThOX mixed core, the well designed U{sub 3}ThOX FAs with 1.94 w/o fissile uranium (mainly {sup 233}U) were located on the periphery of core as a blanket region. U{sub 3}ThOX FAs remained in-core for 6 cycles with the discharged burnup achieving 28 GWD/tHM. Compared with initially loading, the fissile material inventory in U{sub 3}ThOX fuel has increased by 7% via 1-year cooling after discharge. 157 UOX fuel assemblies were located in the inner of UOX/U{sub 3}ThOX mixed core refueling with 64 FAs at each cycle. The designed UOX/PuThOX and UOX/U{sub 3}ThOX mixed core satisfied related nuclear design criteria. The full core performance analyses have shown that mixed core with PuThOX loading has similar impacts as MOX on several neutronic characteristic parameters, such as reduced differential boron worth, higher critical boron concentration, more negative moderator temperature coefficient, reduced control rod worth, reduced shutdown margin, etc.; while mixed core with U{sub 3}ThOX loading on the periphery of core has no

  14. Preliminary evaluation of the gaseous effluent sampling and monitoring systems at the 291-Z-1 and 296-Z-3 stacks

    SciTech Connect

    Schwendiman, L.C.; Glissmeyer, J.A.

    1992-04-01

    The 291-Z-1 and 296-Z-3 stack effluent particulate sampling and monitoring systems are being evaluated for compliance with Atlantic Richfield Hanford Company's Interim Criteria for such systems. This evaluation is part of a study by Battelle-Northwest of gaseous effluent sampling systems in ARHCO facilities. This letter report presents a preliminary evaluation of the mentioned facilities and the indicated improvements needed to meet the Interim Criteria so that conceptual design work for improved systems can be initiated. There is currently underway a detailed study at the two stacks including a series of sampling experiments, the findings of which will not be included in this report. The gaseous effluent sampling system at the 291-Z-1 and 296-Z-3 stacks are very dissimilar and will be treated in separate sections of this report. The discussions for each sampling system will include a brief description and a preliminary evaluation of the systems.

  15. Preliminary evaluation of a serious game for the dissemination and public awareness on preschool children's oral health.

    PubMed

    Ito, Cristina; Marinho Filho, Alfeu V; Ito, Márcia; Azevedo, Marilia M; de Almeida, Maurício Amaral

    2013-01-01

    This article presents the preliminary evaluation by dentists, teachers and parents of a serious game for dissemination of public awareness on preschool children's oral health. In this game, the player keeps a victory condition, while your tooth remains whole. Preliminary evaluation was performed in two parts. The first part was a questionnaire designed to evaluate the applicability of this technology and the opinions on the effectiveness of games in education and in oral health promotion. In the second part, the game is presented and an evaluation questionnaire of it is applied. This study had the participation of 115 persons. There was 80% approval which suggested that the game is an alternative for the prevention of dental awareness. Furthermore, the study perceives that teachers can work together with dentists in order to perform dental prevention. PMID:23920808

  16. A preliminary evaluation of certain NDA techniques for RH-TRU characterization

    SciTech Connect

    Hartwell, J.K.; Yoon, W.Y.; Peterson, H.K.

    1997-11-01

    This report presents the results of modeling efforts to evaluate selected NDA assay methods for RH-TRU waste characterization. The target waste stream was Content Code 104/107 113-liter waste drums that comprise the majority of the INEL`s RH-TRU waste inventory. Two NDA techniques are treated in detail. One primary NDA technique examined is gamma-ray spectrometry to determine the drum fission and activation product content, and fuel sample inventory calculations using the ORIGEN code to predict the total drum inventory. A heavily shielded and strongly collimated HPGe spectrometer system was designed using MCNP modeling. Detection limits and expected precision of this approach were estimated by a combination of Monte Carlo modeling and synthetic gamma-ray spectrum generation. This technique may allow the radionuclide content of these wastes to be determined with relative standard deviations of 20 to 50% depending on the drum matrix and radionuclide. The INEL Passive/Active Neutron (PAN) assay system is the second primary technique considered. A shielded overpack for the 113-liter CC104/107 RH-TRU drums was designed to shield the PAN detectors from excessive gamma radiation. MCNP modeling suggests PAN detection limits of about 0.06 g {sup 235}U and 0.04 g {sup 239}Pu during active assays. 12 refs., 2 figs., 6 tabs.

  17. Importance of the (n,gamma) Cm-247 Evaluation on Neutron Emission in Fast Reactor Fuel Cycle Analysis

    SciTech Connect

    Benoit Forget; Mehdi Asgari; Rodolfo M. Ferrer

    2007-11-01

    As part of the GNEP program, it is envisioned to build a fast reactor for the transmutation of minor actinides. The spent nuclear fuel from the current fleet of light water reactors would be recycled, the current baseline is the UREX+1a process, and would act as a feed for the fast reactor. As the fuel is irradiated in a fast reactor a certain quantity of minor actinides would thus build up in the fuel stream creating possible concerns with the neutron emission of these minor actinides for fuel transportation, handling and fabrication. Past neutronic analyses had not tracked minor actinides above Cm-246 in the transmutation chain, because of the small influence on the overall reactor performance and cycle parameters. However, when trying to quantify the neutron emission from the recycled fuel with high minor actinide content, these higher isotopes play an essential role and should be included in the analysis. In this paper, the influence of tracking these minor actinides on the calculated neutron emission is presented. Also presented is the particular influence of choosing a different evaluated cross section data set to represent the minor actinides above Cm-246. The first representation uses the cross-sections provided by MC2-2 for all isotopes, while the second representation uses infinitely diluted ENDF/BVII.0 cross-sections for Cm-247 to Cf-252 and MC2-2 for all other isotopes.

  18. Radiation-induced stress relaxation in high temperature water of type 316L stainless steel evaluated by neutron diffraction

    NASA Astrophysics Data System (ADS)

    Ishiyama, Y.; Rogge, R. B.; Obata, M.

    2011-01-01

    Weld beads on plate specimens made of type 316L stainless steel were neutron-irradiated up to about 2.5 × 10 25 n/m 2 ( E > 1 MeV) at 561 K in the Japan Material Testing Reactor (JMTR). Residual stresses of the specimens were measured by the neutron diffraction method, and the radiation-induced stress relaxation was evaluated. The values of σ x residual stress (transverse to the weld bead) and σ y residual stress (longitudinal to the weld bead) decreased with increasing neutron dose. The tendency of the stress relaxation was almost the same as previously published data, which were obtained for type 304 stainless steel. From this result, it was considered that there was no steel type dependence on radiation-induced stress relaxation. The neutron irradiation dose dependence of the stress relaxation was examined using an equation derived from the irradiation creep equation. The coefficient of the stress relaxation equation was obtained, and the value was 1.4 (×10 -6/MPa/dpa). This value was smaller than that of nickel alloy.

  19. Three-compartment model: critical evaluation based on neutron activation analysis.

    PubMed

    Silva, Analiza M; Shen, Wei; Wang, ZiMian; Aloia, John F; Nelson, Miriam E; Heymsfield, Steven B; Sardinha, Luis B; Heshka, Stanley

    2004-11-01

    There is renewed interest in Siri's classic three-compartment (3C) body composition model, requiring body volume (BV) and total body water (TBW) estimates, because dual-energy X-ray absorptiometry (DEXA) and in vivo neutron activation (IVNA) systems cannot accommodate subjects with severe obesity. However, the 3C model assumption of a constant ratio (alpha) of mineral (M) to total body protein (TBPro) and related residual mass density (D(RES)) based on cadaver analyses might not be valid across groups differing in sex, race, age, and weight. The aim of this study was to derive new 3C model coefficients in vivo and to compare these estimates to those derived by Siri. Healthy adults (n = 323) were evaluated with IVNA and DEXA and the measured components used to derive alpha and D(RES). For all subjects combined, values of alpha and D(RES) (means +/- SD, 0.351 +/- 0.043; 1.565 +/- 0.023 kg/l) were similar to Siri's proposed values of 0.35 and 1.565 kg/l, respectively. However, alpha and D(RES) varied significantly as a function of sex, race, weight, and age. Expected errors in percent body fat arising by application of Siri's model were illustrated in a second group of 264 adults, including some whose size exceeded DEXA limits but whose BV and TBW had been measured by hydrodensitometry and (2)H(2)O dilution, respectively. Extrapolation of predictions by newly developed models to very high weights allows percent fat error estimation when Siri's model is applied in morbidly obese subjects. The present study results provide a critical evaluation of potential errors in the classic 3C model and present new formulas for use in selected populations.

  20. Evaluation of the neutron background in an HPGe target for WIMP direct detection when using a reactor neutrino detector as a neutron veto system

    SciTech Connect

    Ji, Xiangpan; Xu, Ye Lin, Junsong; Feng, Yulong; Li, Haolin

    2013-11-15

    A direct WIMP (weakly interacting massive particle) detector with a neutron veto system is designed to better reject neutrons. The experimental configuration is studied in this paper involves 984 Ge modules placed inside a reactor-neutrino detector. The neutrino detector is used as a neutron veto device. The neutron background for the experimental design is estimated using the Geant4 simulation. The results show that the neutron background can decrease to O(0.01) events per year per tonne of high-purity germanium and it can be ignored in comparison with electron recoils.

  1. A passive neutron dosemeter based on a CR-39 track detector with multi-field evaluation

    NASA Astrophysics Data System (ADS)

    Savvidis, E.; Alberts, W. G.; Luszik-Bhadra, M.; Zamani, M.

    1994-11-01

    A passive neutron personal dosemeter is proposed which is based on a single CR-39 track detector, covered at four positions with different converters and absorbers. Its dose equivalent response has been investigated with respect to its energy and angle dependence, covering energies from thermal up to 15 MeV and angles of incidence up to 85°. A position-related readout of the electrochemically etched CR-39 detector resulted in four response functions with significant differences for thermal, intermediate and fast neutrons. By an appropriate linear combination of the readings a dose equivalent response has been achieved which varies only within a factor of 2 for thermal neutrons and in the energy range from 20 keV to 15 MeV and shows an acceptable over-response of a factor of 4 for intermediate energy neutrons.

  2. Case study of preliminary cyclic load evaluation and triaxial soil testing in offshore wind farm planning

    NASA Astrophysics Data System (ADS)

    Otto, Daniel; Ossig, Benjamin; Kreiter, Stefan; Kouery, Saed; Moerz, Tobias

    2010-05-01

    In 2020 Germany aims to produce 20% of its electrical power trough renewable energy sources. Assigned Offshore Wind farms in the German exclusive economic zone of the North- and the Baltic Sea are important step toward a fulfilment of this goal. However the save erecting of 5-6 MW wind power plants (total construction size: > 200m) in water depth of around 40 m is related to unprecedented technical, logistical and financial challenges. With an intended lifetime expectation of 50 years for the foundations, construction materials and the soils around the foundation are subject to high and continued stresses from self-weight, waves, wind and current. These stresses are not only static, but have also a significant cyclic component. An estimated 250 million cyclic load changes may lead to an accumulation of plastic deformation in the soil that potentially may affect operability or lifespan of the plant. During a preliminary geotechnical site survey of one of the largest (~150 km2) offshore wind project sites within the German Bight (~45 km North off the island Juist) a total of 16 drill cores with in situ cone penetration data and a total sample length of ~800 m where recovered. Preliminary foundation designs and static self weight and lateral load calculations were used to design a cycling triaxial lab testing program on discrete natural soil samples. Individual tests were performed by foundation type and at vertical and lateral load maxima to evaluate the long-term soil behaviour under cyclic load. Tests have been performed on granular, cohesive and intermediate natural soils. Following an introduction to the unique MARUM triaxial apparatus and testing conditions, the cyclic triaxial test results are shown and explained. Furthermore cyclic shear strength and stiffness are compared to their static counterparts. Unique soil behaviour like abrupt partial failure, pore pressure response and unexpected in part load independent cyclic deformation behaviour is discussed and

  3. Preliminary evaluation of alternative forms for immobilization of Hanford high-level defense wastes

    SciTech Connect

    Schulz, W.W.; Beary, M.M.; Gallagher, S.A.; Higley, B.A.; Johnston, R.G.; Jungfleisch, F.M.; Kupfer, M.J.; Palmer, R.A.; Watrous, R.A.; Wolf, G.A.

    1980-09-01

    A preliminary evaluation of solid waste forms for immobilization of Hanford high-level radioactive defense wastes is presented. Nineteen different waste forms were evaluated and compared to determine their applicability and suitability for immobilization of Hanford salt cake, sludge, and residual liquid. This assessment was structured to address waste forms/processes for several different leave-retrieve long-term Hanford waste management alternatives which give rise to four different generic fractions: (1) sludge plus long-lived radionuclide concentrate from salt cake and residual liquid; (2) blended wastes (salt cake plus sludge plus residual liquid); (3) residual liquid; and (4) radionuclide concentrate from residual liquid. Waste forms were evaluated and ranked on the basis of weighted ratings of seven waste form and seven process characteristics. Borosilicate Glass waste forms, as marbles or monoliths, rank among the first three choices for fixation of all Hanford high-level wastes (HLW). Supergrout Concrete (akin to Oak Ridge National Laboratory Hydrofracture Process concrete) and Bitumen, low-temperature waste forms, rate high for bulk disposal immobilization of high-sodium blended wastes and residual liquid. Certain multi-barrier (e.g., Coated Ceramic) and ceramic (SYNROC Ceramic, Tailored Ceramics, and Supercalcine Ceramic) waste forms, along with Borosilicate Glass, are rated as the most satisfactory forms in which to incorporate sludges and associated radionuclide concentrates. The Sol-Gel process appears superior to other processes for manufacture of a generic ceramic waste form for fixation of Hanford sludge. Appropriate recommendations for further research and development work on top ranking waste forms are made.

  4. R-Matrix Evaluation of 16O Neutron Cross Sections up to 6.3 MeV

    SciTech Connect

    Sayer, R.O.

    2000-08-21

    In this paper we describe an evaluation of {sup 16}O neutron cross sections in the resolved resonance region with the multilevel Reich-Moore R-matrix formalism. Resonance analyses were performed with the computer code SAMMY [LA98] which utilizes Bayes method, a generalized least squares technique. Over the years the nuclear community has developed a collection of evaluated nuclear data for applications in thermal, fast reactor, and fusion systems. However, typical neutron spectra in criticality safety applications are different from the spectra relevant to thermal, fast reactor, and fusion systems. In fact, the neutron spectra important for these non-reactor systems appear to peak in the epithermal energy range. Nuclear data play a major role in the calculation of the criticality safety margins for these systems. A thorough examination of how the present collection of nuclear data evaluations behaves in criticality safety calculations is needed. Many older evaluations will probably need to be revised, and new evaluations will be needed. Oxygen is an important element in criticality safety applications where oxides are present in significant abundance. The existing ENDF/B-VI.5 evaluation is expressed in terms of point-wise cross sections derived from the analysis of G. Hale [HA91]. Unfortunately such an evaluation is not directly useful for resonance analysis of data from samples in which oxygen is combined with other elements; for that purpose, Reich-Moore resonance parameters are needed. This paper addresses the task of providing those parameters. In the following sections we discuss the data, resonance analysis procedure, and results.

  5. Preliminary evaluation of the learning outcome achieved by a nursing research seminar course for doctoral students.

    PubMed

    Lou, Meei-Fang; Chen, Yueh-Chih

    2008-06-01

    Educational evaluation is a priority policy of the Ministry of Education and student learning outcome is an important criterion used in educational evaluation work. The purpose of this study was to evaluate the learning outcome of a newly developed course for doctoral students entitled, Nursing Research Seminar. The course was one semester in length and required students to attend 2 hours of class per week. Student learning outcome was evaluated based on the level of understanding students had of course objectives. The six objectives of this course were: evaluating and integrating research papers; enhancing critical thinking skills; gaining an in-depth understanding of the literature related to topics of interest; enhancing ability to construct research proposals; guiding student dissertation work; and refining critical research skills. Data were collected from the responses provided by 25 students on a 5-point Likert-type evaluation form based on course objectives filled out during the last class of the semester. Descriptive and non-parametric statistics were adopted. Results showed: (1) The average post-course score (24.76 +/- 2.89) was significantly higher than the pre-course score (18.40 +/- 5.52); (2) Students realized significant improvements in all six objectives at the end of the course; (3) There were statistically significant differences in improvement scores in all six objectives for students in different years of their doctoral program; (4) The lower the year in the program, the higher the improvement scores for each course objective; (5) The two objectives of the six that saw the most significant improvements were "gaining an in-depth understanding of the literature related to topics of interest", and "enhancing critical thinking skills". Because of the small sample size, conclusions drawn from this study should be treated as tentative. Findings provide preliminary information supporting the importance and necessity of offering the Nursing Research

  6. Partitioning planning studies: Preliminary evaluation of metal and radionuclide partitioning the high-temperature thermal treatment systems

    SciTech Connect

    Liekhus, K.; Grandy, J.; Chambers, A.

    1997-03-01

    A preliminary study of toxic metals and radionuclide partitioning during high-temperature processing of mixed waste has been conducted during Fiscal Year 1996 within the Environmental Management Technology Evaluation Project. The study included: (a) identification of relevant partitioning mechanisms that cause feed material to be distributed between the solid, molten, and gas phases within a thermal treatment system; (b) evaluations of existing test data from applicable demonstration test programs as a means to identify and understand elemental and species partitioning; and, (c) evaluation of theoretical or empirical partitioning models for use in predicting elemental or species partitioning in a thermal treatment system. This preliminary study was conducted to identify the need for and the viability of developing the tools capable of describing and predicting toxic metals and radionuclide partitioning in the most applicable mixed waste thermal treatment processes. This document presents the results and recommendations resulting from this study that may serve as an impetus for developing and implementing these predictive tools.

  7. Preliminary joint X-ray and neutron protein crystallographic studies of ecDHFR complexed with folate and NADP{sup +}

    SciTech Connect

    Wan, Qun Kovalevsky, Andrey Y.; Wilson, Mark A.; Bennett, Brad C.; Langan, Paul; Dealwis, Chris

    2014-05-25

    A 2.0 Å resolution neutron data set and a 1.6 Å resolution X-ray data set were collected for joint X-ray/neutron refinement of the ecDHFR–folate–NADP{sup +} complex in order to study the reaction mechanism of dihydrofolate reductase.

  8. Development of transmissometer system for evaluating molecular contamination effects and the preliminary results

    NASA Astrophysics Data System (ADS)

    Itoh, Nobunari; Katoh, Masahiro; Okano, Nobuaki

    2005-01-01

    The presence of propagated molecular gas is one of the most probable causes of on-orbit degradation. The performance of optical sensors would be affected seriously if the strong absorption bands of the contaminants exist in the region of our interest and phase transition of adsorption gas on optical surfaces would induce not only absorption but also scatter. Although there are amount of trials to predict spectral degradation with model calculations, experimental approaches are also necessary to clarify degradation processes occurred in orbit and to improve the on-board calibration reliability. We built up the measurement system in order to evaluate transmittance degradation with various kinds of gases under different temperature and vacuum conditions. In our system, an optical glass, the site of adsorption, is set inside a cryostat and then a certain amount of molecular gas is injected. The amount of injected gas adsorption onto the optical surface is controlled by adjusting the sample surface temperature. Our systems have the capability to control vacuum within the range from 10-3Pa to 102Pa and temperature from 150K to 423K. As for the measurement of transmittance change, we adopted commercially available spectrophotometer and FTIR. The optical spectrophotometer covers the wavelength range from 300nm to 2.5um and the FTIR covers from 2um to 25um. We would present the details of our system and discuss about measurement accuracy and preliminary results of our measurements.

  9. Implementation of an enhanced probation program: evaluating process and preliminary outcomes.

    PubMed

    Shannon, Lisa M; Hulbig, Shelia K; Birdwhistell, Shira; Newell, Jennifer; Neal, Connie

    2015-04-01

    Supervision, Monitoring, Accountability, Responsibility, and Treatment (SMART) is Kentucky's enhanced probation pilot program modeled after Hawaii's Opportunity Probation with Enforcement (HOPE). SMART is proposed to decrease substance use, new violations, and incarceration-related costs for high-risk probationers by increasing and randomizing drug testing, intensifying supervision, and creating linkages with needed resources (i.e., mental health and substance use). SMART adopts a holistic approach to rehabilitation by addressing mental health and substance abuse needs as well as life skills for fostering deterrence of criminal behavior vs. punitive action only. A mixed methods evaluation was implemented to assess program implementation and effectiveness. Qualitative interviews with key stakeholders (i.e., administration, judges, attorneys, and law enforcement/corrections) suggested successful implementation and collaboration to facilitate the pilot program. Quantitative analyses of secondary Kentucky Offender Management System (KOMS) data (grant Year 1: 07/01/2012-06/30/2013) also suggested program effectiveness. Specifically, SMART probationers showed significantly fewer: violations of probation (1.2 vs. 2.3), positive drug screens (8.6% vs. 29.4%), and days incarcerated (32.5 vs. 118.1) than comparison probationers. Kentucky's SMART enhanced probation shows preliminary success in reducing violations, substance use, and incarceration. Implications for practice and policy will be discussed.

  10. Smart Weapons Operability Enhancement Joint Test and Evaluation Program Grayling 1: preliminary results

    NASA Astrophysics Data System (ADS)

    Welsh, James P.; Koenig, George G.

    1993-08-01

    The primary objective of the Smart Weapons Operability Enhancement (SWOE) Joint Test and Evaluation (JT&E) Program is to validate the SWOE Process for the Office of the Secretary of Defense. The SWOE Process is a physics based scene generation capability that will enhance the performance of future smart weapon systems for a global variety of battlefield environments. This process is focused on generating complex background environmental scenes, including targets, for a world wide range of battlefield conditions. The SWOE program is a DoD wide partnership incorporating capabilities from the Army, Navy, Marine Corps and Air Force. The principal thrusts of SWOE are to quantitatively define the environmental factors and processes and to provide the capabilities to measure, model, render and extrapolate their impact on smart weapon system performance. The Grayling I exercise is the first in a series of four coordinate field deployments focused on validation of the SWOE Process. This paper describes the experimental design, sampling plans, measurement efforts and summarizes preliminary results of the Grayling I exercise.

  11. Ultra-high-speed studies of shock phenomena in a miniaturized system: A preliminary evaluation

    SciTech Connect

    Trott, W.M.; Erickson, K.L.

    1997-09-01

    A laboratory-scale experimental test system for small-scale of shock phenomena has been assembled. This system uses a variety of miniature test platforms in which shock loading is provided by laser-driven flyer impact. Acceptor materials include thin-film explosives and high-density metal foils. Optical access is provided for high-speed optical diagnostics such as optically recording velocity interferometry and single-pulse Raman spectroscopy. The experimental assembly for Raman studies features a common laser source for both flyer generation and excitation of Raman scattering (to achieve high timing precision) and a detection scheme that uses the coupling fiber for the excitation source to collect with high efficiency backscattered Raman light. Preliminary system evaluation experiments indicate that detailed particle velocity studies of the dynamic material properties of high-density metals under short-pulse, high-strain-rate loading can be performed in a miniaturized test configuration. Single-pulse Raman studies on shock compressed thin film explosives also appear feasible if the thickness and grain structure of these films can be tailored to enhance the Raman scattering signal sufficiently. Possible improvements in the experimental design and a number of likely applications of these techniques are also discussed.

  12. Preliminary Evaluation of a Web-Oriented Assessment Tool for Emotion Recognition.

    PubMed

    Pampouchidou, Anastasia; Kazantzaki, Eleni; Karatzanis, Ioannis; Marias, Kostas; Tsiknakis, Manolis; Meriaudeau, Fabrice; Yang, Fan; Simos, Panagiotis

    2016-01-01

    Perceiving and identifying emotions on facial expressions is one of the basic abilities that compose emotional intelligence, and is crucial for normal social functions. It is well documented that facial expression conveys information about felt emotion, and that expressive behavior can activate or regulate the emotion required by a given situation. Instruments measuring emotion perception based on facial expression have been found in literature either as stand-alone scales or as part of other tests. The proposed tool expands existing instruments to combine online availability while affording assessment of emotion recognition on a continuum of intensity. It was founded on Ekman's Facial Action Units, with two Virtual Characters (male and female) portraying five basic emotions Anger, Disgust, Fear, Joy, Sadness, plus Neutral expression. The user can navigate on the custom-made pentagon and choose the emotion and intensity level (1-5) through a single click. The preliminary evaluation of the tool on thirty normal subjects provided threshold data that can later be used as benchmarks to assess emotion perception sensitivity in psychiatric disorders such as depression and schizophrenia characterized by emotional dysfunction. PMID:27225560

  13. Design and preliminary evaluation of an exoskeleton for upper limb resistance training

    NASA Astrophysics Data System (ADS)

    Wu, Tzong-Ming; Chen, Dar-Zen

    2012-06-01

    Resistance training is a popular form of exercise recommended by national health organizations, such as the American College of Sports Medicine (ACSM) and the American Heart Association (AHA). This form of training is available for most populations. A compact design of upper limb exoskeleton mechanism for homebased resistance training using a spring-loaded upper limb exoskeleton with a three degree-of-freedom shoulder joint and a one degree-of-freedom elbow joint allows a patient or a healthy individual to move the upper limb with multiple joints in different planes. It can continuously increase the resistance by adjusting the spring length to train additional muscle groups and reduce the number of potential injuries to upper limb joints caused by the mass moment of inertia of the training equipment. The aim of this research is to perform a preliminary evaluation of the designed function by adopting an appropriate motion analysis system and experimental design to verify our prototype of the exoskeleton and determine the optimal configuration of the spring-loaded upper limb exoskeleton.

  14. Laser Doppler flowmetry: in the assessment of peripheral vascular disorders? A preliminary evaluation.

    PubMed

    Cochrane, T; Sheriff, S B; Boulton, A J; Ward, J D; Atkins, R M

    1986-02-01

    Skin is a representative microvascular bed providing easy access for the study of capillary haemodynamics. In this preliminary evaluation we have used laser Doppler flowmetry to measure the response of skin capillary blood flow to local thermal stimulation. The purpose of our study was to see if such measurements can be used to derive useful clinical information. Thirty subjects, 15 male and 15 female, were selected to establish "normal' patterns of behaviour. All normal subjects studied showed similar patterns of response. There was a slight downward trend in red-blood-cell flux with age. Periods of vasomotor activity were present at rates ranging from 4-17 cycles/min. The mean temperature rise in the heated skin area was 4 degrees C. Blood flow over this range increased by a factor of 10 or more. Clinical cases studied were strictly limited to three categories of disease with known or suspected microvascular changes: algodystrophy, lower-limb ischaemia and diabetic neuropathy. All the clinical cases studied showed deviations from the normal pattern. Patients with algodystrophy had impaired peripheral vascular function in the affected area. Patients with lower-limb ischaemic problems all had poor peripheral perfusion. In the limited number of diabetic neuropathic feet studied two patterns emerged: patients with no evidence of ulceration displayed striking vasomotor activity; those with more severe problems had reduced red-blood-cell flux and little evidence of vasomotor control.

  15. A preliminary physicochemical evaluation of Darvyadi Yoni Varti: A compound Ayurvedic formulation

    PubMed Central

    Rupapara, Amit V.; Donga, Shilpa B.; Harisha, C.R.; Shukla, Vinay J.

    2014-01-01

    Background: Darvyadi Yoni Varti is an Ayurvedic formulation indicated for the management of Garbhasaya Grivamukhagata Vrana (cervical erosion). Though a number of drugs are available in modern medicine, interest towards Ayurveda is gaining. Drugs with Vranasodhana, Ropana and Prasadana properties like Sphatika, Darvi, Haridra, and Lodhra are useful in this situation and are selected to prepare Yoni Varti. Aim: To standardize and evaluate preliminary pharmacognostical as well as physicochemical profiles of Darvyadi Yoni Varti. Materials and Methods: Raw material was analyzed in the Pharmacognostical Laboratory for genuinity before converting into Varti. Finished product was analyzed by following pharmacopoeial standards. Results: The pH value of Darvyadi Yoni Varti was 5.0, water soluble extract was 23.3%w/w, alcohol soluble extract was 8.7%w/w, ash value was 5.16%w/w, loss on drying was 71.73%w/w. High performance thin layer chromatography was carried out; in which maximum 10 spots at 254 nm and 3 spots at 366 nm were distinguished. Conclusion: Pharmacognostical study of raw drug revealed the quality and genuineness of all the constituents of Darvyadi Yoni Varti. PMID:26195915

  16. A Preliminary Evaluation of Using Fill Materials to Stabilize Used Nuclear Fuel During Storage and Transportation

    SciTech Connect

    Maheras, Steven J.; Best, Ralph; Ross, Steven B.; Lahti, Erik A.; Richmond, David J.

    2012-08-01

    This report contains a preliminary evaluation of potential fill materials that could be used to fill void spaces in and around used nuclear fuel contained in dry storage canisters in order to stabilize the geometry and mechanical structure of the used nuclear fuel during extended storage and transportation after extended storage. Previous work is summarized, conceptual descriptions of how canisters might be filled were developed, and requirements for potential fill materials were developed. Elements of the requirements included criticality avoidance, heat transfer or thermodynamic properties, homogeneity and rheological properties, retrievability, material availability and cost, weight and radiation shielding, and operational considerations. Potential fill materials were grouped into 5 categories and their properties, advantages, disadvantages, and requirements for future testing were discussed. The categories were molten materials, which included molten metals and paraffin; particulates and beads; resins; foams; and grout. Based on this analysis, further development of fill materials to stabilize used nuclear fuel during storage and transportation is not recommended unless options such as showing that the fuel remains intact or canning of used nuclear fuel do not prove to be feasible.

  17. Preliminary Evaluation of Probiotic Properties of Lactobacillus Strains Isolated from Sardinian Dairy Products

    PubMed Central

    Pisano, Maria Barbara; Viale, Silvia; Conti, Stefania; Deplano, Maura; Melis, Maria Paola; Deiana, Monica

    2014-01-01

    Twenty-three Lactobacillus strains of dairy origin were evaluated for some functional properties relevant to their use as probiotics. A preliminary subtractive screening based on the abilities to inhibit the growth of microbial pathogens and hydrolyze conjugated bile salts was applied, and six strains were selected for further characterization including survival under gastrointestinal environmental conditions, adhesion to gut epithelial tissue, enzymatic activity, and some safety properties. All selected strains maintained elevated cell numbers under conditions simulating passage through the human gastrointestinal tract, well comparable to the values obtained for the probiotic strain Lactobacillus rhamnosus GG, and were able to adhere to Caco-2 cells to various extents (from 3 to 20%). All strains exhibited high aminopeptidase, and absent or very low proteolytic and strong β-galactosidase activities; none was found to be haemolytic or to produce biogenic amines and all were susceptible to tetracycline, chloramphenicol, erythromycin, ampicillin, and amoxicillin/clavulanic acid. Our results indicate that the Lactobacillus strains analyzed could be considered appropriate probiotic candidates, due to resistance to GIT simulated conditions, antimicrobial activity, adhesion to Caco-2 cell-line, and absence of undesirable properties. They could be used as adjunct cultures for contributing to the quality and health related functional properties of dairy products. PMID:25054135

  18. Preliminary evaluation of PTSD Coach, a smartphone app for post-traumatic stress symptoms.

    PubMed

    Kuhn, Eric; Greene, Carolyn; Hoffman, Julia; Nguyen, Tam; Wald, Laura; Schmidt, Janet; Ramsey, Kelly M; Ruzek, Josef

    2014-01-01

    PTSD Coach is a mobile application (app) designed to help individuals who have post-traumatic stress disorder (PTSD) symptoms better understand and self-manage their symptoms. It has wide-scale use (over 130,000 downloads in 78 countries) and very favorable reviews but has yet to be evaluated. Therefore, this study examines user satisfaction, perceived helpfulness, and usage patterns of PTSD Coach in a sample of 45 veterans receiving PTSD treatment. After using PTSD Coach for several days, participants completed a survey of satisfaction and perceived helpfulness and focus groups exploring app use and benefit from use. Data indicate that participants were very satisfied with PTSD Coach and perceived it as being moderately to very helpful with their PTSD symptoms. Analysis of focus group data resulted in several categories of app use: to manage acute distress and PTSD symptoms, at scheduled times, and to help with sleep. These findings offer preliminary support for the acceptability and perceived helpfulness of PTSD Coach and suggest that it has potential to be an effective self-management tool for PTSD. Although promising, future research is required to validate this, given study limitations.

  19. Preliminary Phytochemical and Antibacterial Evaluation of Crude Aqueous Extract of Psidium guajava Leaf

    NASA Astrophysics Data System (ADS)

    Geidam, Y. A.; Ambali, A. G.; Onyeyili, P. A.

    The leaves of Psidium guajava is used in folk medicine as an antidiarrhoic in Nigeria and many other countries of the world. It is also employed for the treatment of vertigo and regulation of menstrual periods. World health organization encourages and indicated that studies on medicinal plants should include both identification of chemical constituents and determination of the biological activities of such plants. In this preliminary study, phytochemical and antibacterial properties of crude aqueous extract of Psidium guajava leaf were evaluated. The extract was subjected to qualitative chemical screening for identification of various classes of active chemical constituents while disc diffusion method was used to determine the antibacterial properties of the extract against some gram positive and gram negative bacteria. The extract showed the presence of tannins, saponins, carbohydrates, flavonoids, steroids and cardiac glycosides. The extract inhibited the growth of Salmonella typhi and Klebsiella pneumoniae, but has no effect on the growth of Escherichia coli, Staphylococcus aureus and Streptococcus fecalis organisms. The study revealed some antibacterial properties of the extract that justify the use of the plant in folk medicine. However, further studies need to be carried out to identify the potentials of the plant to be considered as a natural source of antibacterial agent.

  20. Investigation of human exposure to triclocarban after showering and preliminary evaluation of its biological effects.

    PubMed

    Schebb, Nils Helge; Inceoglu, Bora; Ahn, Ki Chang; Morisseau, Christophe; Gee, Shirley J; Hammock, Bruce D

    2011-04-01

    The antibacterial soap additive triclocarban (TCC) is widely used in personal care products. TCC has a high environmental persistence. We developed and validated a sensitive online solid-phase extraction-LC-MS/MS method to rapidly analyze TCC and its major metabolites in urine and other biological samples to assess human exposure. We measured human urine concentrations 0-72 h after showering with a commercial bar soap containing 0.6% TCC. The major route of renal elimination was excretion as N-glucuronides. The absorption was estimated at 0.6% of the 70±15 mg of TCC in the soap used. The TCC-N-glucuronide urine concentration varied widely among the subjects, and continuous daily use of the soap led to steady state levels of excretion. In order to assess potential biological effects arising from this exposure, we screened TCC for the inhibition of human enzymes in vitro. We demonstrate that TCC is a potent inhibitor of the enzyme soluble epoxide hydrolase (sEH), whereas TCC's major metabolites lack strong inhibitory activity. Topical administration of TCC at similar levels to rats in a preliminary in vivo study, however, failed to alter plasma biomarkers of sEH activity. Overall the analytical strategy described here revealed that use of TCC soap causes exposure levels that warrant further evaluation. PMID:21381656

  1. Preliminary Evaluation of GEOS-5 Aerosol and CO Distributions Forecast During TC4

    NASA Technical Reports Server (NTRS)

    Colarco, Peter R.

    2007-01-01

    The NASA Tropical Composition, Cloud, and Climate Coupling (TC4) Mission was based out San Jose, Costa Rica during July and August 2007. During TC4 the NASA Global Modeling and Assimilation Office (GMAO) ran twice-daily 0.5 x 0.666 global 5-day forecasts of the Goddard Earth Observing System atmospheric general circulation model and data assimilation system (GEOS-5). This implementation of GEOS-5 contained an aerosol and carbon monoxide (CO) model to provide online forecast tropospheric distributions of dust, sea salt, sulfate, and carbonaceous aerosols and CO for both the planning of flights and for science. Here we provide a description of the aerosol and CO modeling system and give a preliminary evaluation of forecast tracer distributions. Our comparisons to satellite observations of aerosol and CO show qualitatively similar simulated distributions of tracers to those observed. During TC4 copious amounts of dust were observed in the Caribbean. The model generally reproduced the observations of the timing of dust events and the vertical structure in the lower atmosphere. However, the model simulations had too much aerosol at high altitudes relative to airborne Cloud Physics Lidar observations. The results were similar for biomass burning aerosol and CO tracers, where the model showed higher simulated concentrations of these tracers at aircraft flight altitude than observations.

  2. Preliminary evaluation of potential substitutes for chlorofluorocarbon refrigerants at Lawrence Livermore National Laboratory

    SciTech Connect

    Rogozen, M.B. )

    1989-12-30

    Chlorofluorocarbons (CFCs) are organic compounds composed of carbon, chlorine and fluorine. CFCs are widely used as refrigerants, solvents, and blowing agents, and, although they are chemically inert in the lower atmosphere, CFCs break apart upon reaching the stratosphere and release chlorine, which destroys ozone molecules that serve as the earth's natural barrier to harmful ultraviolet radiation. Growing concern about the damage to stratospheric ozone has led to an international treaty to limit production and use of certain chlorofluorocarbons. Since the use of CFCs is so extensive, major efforts are under way to identify, test, and commercialize CFC substitutes. The objectives of the preliminary investigation reported here were to identify likely substitutes for CFCs used a refrigerants at Lawrence Livermore National Laboratory (LLNL), and to evaluate current information on their feasibility and health effects. Section 2 contains a brief discussion of the regulatory background. Section 3 describes the chlorofluorocarbon refrigerants currently used at LLNL. Substitutes are identified and discussed in Section 4. Section 5 contains recommendations for further research, and references are presented in Section 6. 29 refs., 3 figs., 3 tabs.

  3. Development and Preliminary Evaluation of a Spray Deposition Sensing System for Improving Pesticide Application

    PubMed Central

    Kesterson, Melissa A.; Luck, Joe D.; Sama, Michael P.

    2015-01-01

    An electronic, resistance-based sensor array and data acquisition system was developed to measure spray deposition from hydraulic nozzles. The sensor surface consisted of several parallel tin plated copper traces of varying widths with varying gap widths. The system contained an embedded microprocessor to monitor output voltage corresponding to spray deposition every second. In addition, a wireless module was used to transmit the voltage values to a remote laptop. Tests were conducted in two stages to evaluate the performance of the sensor array in an attempt to quantify the spray deposition. Initial tests utilized manual droplet placement on the sensor surface to determine the effects of temperature and droplet size on voltage output. Secondary testing utilized a spray chamber to pass nozzles at different speeds above the sensor surface to determine if output varied based on different application rates or spray droplet classification. Results from this preliminary analysis indicated that manual droplets of 5 and 10 μL resulted in significantly different values from the sensors while temperature did not consistently affect output. Spray chamber test results indicated that different application rates and droplet sizes could be determined using the sensor array. PMID:26694417

  4. Construction and preliminary evaluation of copper tailings reclamation test plots at Cyprus Miami Mining Corporation

    SciTech Connect

    Chammas, G.A.; McCaulou, D.R.; Jones, G.L.

    1999-07-01

    Twenty pilot-scale test plots were constructed in mid-1998 at the Cyprus Miami mine to investigate the feasibility and cost-effectiveness of various reclamation strategies for establishment of self-sustaining native vegetation on acidic copper tailings. Four reclamation strategies are being tested: (1) directly covering acidic tailings with varying thicknesses f cover soil; (2) removing and/or neutralizing particularly acidic surgical tailings before soil cover placement, (3) chemically and/or physically inhibiting upward water and solute movement using neutralizing and neutral capillary barriers, and (4) constructing a subgrade of neutral tailings beneath cover soil. Preliminary results suggest that thicker soil covers and capillary barrier test plots initially support vegetation to a greater extent than other test plots, probably because of their increased moisture storage capacity. Results also suggest that salts are beginning to migrate upward from underlying tailings into cover soil. Data collected from ongoing vegetation surveys and soil testing will be used to evaluate the effect of various reclamation strategies on vegetation establishment and the potential impact of upward salt migration.

  5. The Prompt Fission Neutron Spectrum: From Experiment to the Evaluated Data and its Impact on Critical Assemblies

    SciTech Connect

    Rising, Michael Evan

    2015-06-10

    After a brief introduction concerning nuclear data, prompt fission neutron spectrum (PFNS) evaluations and the limited PFNS covariance data in the ENDF/B-VII library, and the important fact that cross section uncertainties ~ PFNS uncertainties, the author presents background information on the PFNS (experimental data, theoretical models, data evaluation, uncertainty quantification) and discusses the impact on certain well-known critical assemblies with regard to integral quantities, sensitivity analysis, and uncertainty propagation. He sketches recent and ongoing research and concludes with some final thoughts.

  6. Residual stress evaluation in martensitic stainless steel as a function of gas quenching pressure using thermal neutrons

    NASA Astrophysics Data System (ADS)

    Doyle, Edward D.; Wong, Yat Choy; Ripley, Maurice I.

    2006-11-01

    The distribution of bulk residual stress was evaluated for two modified grades of martensitic stainless steels. Residual stress levels generated in the two steels were evaluated as a function of quenching gas pressure in vacuum heat treatment using neutron diffraction. It was observed that the levels of residual stress increased with increasing gas pressure, with the high hardenability grade showing the greater increase. However, quenching at 6 bar gas pressure resulted in a significant drop in the levels of residual stress, an observation that is interpreted in terms of the accommodation of high levels of strain by the presence of high levels of interlath retained austenite.

  7. Preliminary evaluation of porcine zona pellucida (PZP) immunocontraception for behavioral effects in feral horses (Equus caballus).

    PubMed

    Powell, D M

    1999-01-01

    Successful management of captive populations of wild animals requires effective control of reproduction. Contraception is one tool for controlling reproduction of animals in zoos; however, the options available to the animal manager are limited. Contraceptives vary in efficacy, reversibility, and side effects, and thus may not be suitable for widespread use. One consideration when selecting a contraceptive is its potential for side effects on behavior, especially given the fact that reproduction plays such a prominent role in the biology of any species. To date, there have been few evaluations of contraceptives for behavioral effects, and those that have been conducted have focused on hormone-based contraceptives. This study sought to evaluate a novel method of population control, immunocontraception, for behavioral effects in a population of feral horses. Porcine zona pellucida (PZP) immunocontraception prevents fertilization of ova and does not alter normal hormone secretion patterns. It therefore should leave the animal behaviorally intact in terms of reproductive behavior. The study examined the behavior of 43 sexually mature mares on Assateague Island during the 1997 breeding season and, with help from Earthwatch volunteers, collected observations over a 3-month period. The study found no significant differences between treated and untreated mares in general activity budget, aggression given or received, and spatial relationships relative to the stallion. These preliminary findings indicate that PZP contraception seems to have no acute behavioral effects on the behavior of individuals. The study findings also suggest that PZP could be a desirable and effective management tool for captive species in which social behavior plays an integral role in group dynamics. Analyses of group level effects and population level effects are continuing.

  8. Preliminary evaluation of porcine zona pellucida (PZP) immunocontraception for behavioral effects in feral horses (Equus caballus).

    PubMed

    Powell, D M

    1999-01-01

    Successful management of captive populations of wild animals requires effective control of reproduction. Contraception is one tool for controlling reproduction of animals in zoos; however, the options available to the animal manager are limited. Contraceptives vary in efficacy, reversibility, and side effects, and thus may not be suitable for widespread use. One consideration when selecting a contraceptive is its potential for side effects on behavior, especially given the fact that reproduction plays such a prominent role in the biology of any species. To date, there have been few evaluations of contraceptives for behavioral effects, and those that have been conducted have focused on hormone-based contraceptives. This study sought to evaluate a novel method of population control, immunocontraception, for behavioral effects in a population of feral horses. Porcine zona pellucida (PZP) immunocontraception prevents fertilization of ova and does not alter normal hormone secretion patterns. It therefore should leave the animal behaviorally intact in terms of reproductive behavior. The study examined the behavior of 43 sexually mature mares on Assateague Island during the 1997 breeding season and, with help from Earthwatch volunteers, collected observations over a 3-month period. The study found no significant differences between treated and untreated mares in general activity budget, aggression given or received, and spatial relationships relative to the stallion. These preliminary findings indicate that PZP contraception seems to have no acute behavioral effects on the behavior of individuals. The study findings also suggest that PZP could be a desirable and effective management tool for captive species in which social behavior plays an integral role in group dynamics. Analyses of group level effects and population level effects are continuing. PMID:16363936

  9. A Mobile App to Aid Smoking Cessation: Preliminary Evaluation of SmokeFree28

    PubMed Central

    Wong, Wai Chi

    2015-01-01

    Background Little is known about the effectiveness of mobile apps in aiding smoking cessation or their validity for automated collection of data on smoking cessation outcomes. Objective We conducted a preliminary evaluation of SF28 (SF28 is the name of the app, short for SmokeFree28)—an app aimed at helping smokers to be smoke-free for 28 days. Methods Data on sociodemographic characteristics, smoking history, number of logins, and abstinence at each login were uploaded to a server from SF28 between August 2012 and August 2013. Users were included if they were aged 16 years or over, smoked cigarettes at the time of registration, had set a quit date, and used the app at least once on or after their quit date. Their characteristics were compared with data from a representative sample of smokers trying to stop smoking in England. The percentage of users recording 28 days of abstinence was compared with a value of 15% estimated for unaided quitting. Correlations were assessed between recorded abstinence for 28 days and well-established abstinence predictors. Results A total of 1170 users met the inclusion criteria. Compared with smokers trying to quit in England, they had higher consumption, and were younger, more likely to be female, and had a non-manual rather than manual occupation. In total, 18.9% (95% CI 16.7-21.1) were recorded as being abstinent from smoking for 28 days or longer. The mean number of logins was 8.5 (SD 9.0). The proportion recording abstinence for 28 days or longer was higher in users who were older, in a non-manual occupation, and in those using a smoking cessation medication. Conclusions The recorded 28-day abstinence rates from the mobile app, SF28, suggest that it may help some smokers to stop smoking. Further evaluation by means of a randomized trial appears to be warranted. PMID:25596170

  10. RE-EVALUATION OF THE NEUTRON EMISSION FROM THE SOLAR FLARE OF 2005 SEPTEMBER 7, DETECTED BY THE SOLAR NEUTRON TELESCOPE AT SIERRA NEGRA

    SciTech Connect

    González, L. X.; Valdés-Galicia, J. F.; Musalem, O.; Hurtado, A.; Sánchez, F.; Muraki, Y.; Sako, T.; Matsubara, Y.; Nagai, Y.; Watanabe, K.; Shibata, S.; Sakai, T.

    2015-12-01

    The X17.0 solar flare of 2005 September 7 released high-energy neutrons that were detected by the Solar Neutron Telescope (SNT) at Sierra Negra, Mexico. In three separate and independent studies of this solar neutron event, several of its unique characteristics were studied; in particular, a power-law energy spectra was estimated. In this paper, we present an alternative analysis, based on improved numerical simulations of the detector using GEANT4, and a different technique for processing the SNT data. The results indicate that the spectral index that best fits the neutron flux is around 3, in agreement with previous works. Based on the numerically calculated neutron energy deposition on the SNT, we confirm that the detected neutrons might have reached an energy of 1 GeV, which implies that 10 GeV protons were probably produced; these could not be observed at Earth, as their parent flare was an east limb event.

  11. Re-evaluation of the Neutron Emission from the Solar Flare of 2005 September 7, Detected by the Solar Neutron Telescope at Sierra Negra

    NASA Astrophysics Data System (ADS)

    González, L. X.; Valdés-Galicia, J. F.; Sánchez, F.; Muraki, Y.; Sako, T.; Watanabe, K.; Matsubara, Y.; Nagai, Y.; Shibata, S.; Sakai, T.; Musalem, O.; Hurtado, A.

    2015-12-01

    The X17.0 solar flare of 2005 September 7 released high-energy neutrons that were detected by the Solar Neutron Telescope (SNT) at Sierra Negra, Mexico. In three separate and independent studies of this solar neutron event, several of its unique characteristics were studied; in particular, a power-law energy spectra was estimated. In this paper, we present an alternative analysis, based on improved numerical simulations of the detector using GEANT4, and a different technique for processing the SNT data. The results indicate that the spectral index that best fits the neutron flux is around 3, in agreement with previous works. Based on the numerically calculated neutron energy deposition on the SNT, we confirm that the detected neutrons might have reached an energy of 1 GeV, which implies that 10 GeV protons were probably produced; these could not be observed at Earth, as their parent flare was an east limb event.

  12. a Re-Evaluation of the Neutron Emission from the Solar Flare of September 07, 2005, Detected by the Solar Neutron Telescope at Sierra Negra.

    NASA Astrophysics Data System (ADS)

    González, Xavier

    The X17.0 solar flare of September 7, 2005 released high-energy neutrons, which were detected by the Solar Neutron Telescope (SNT) at Sierra Negra, Mexico. In three separate and independent studies of this solar neutron event, the energy spectra was calculated as a power law. In this paper, we present an alternative analysis, based on improved numerical simulations of the detector using GEANT4, and a different technique to process the SNT data. The results indicate that the spectral index which best fits the neutron flux is around 3, in agreement with previous works. Based on the numerically calculated neutron energy deposition on the SNT, we confirm that the neutrons detected had at least 1 GeV, this implies that the parent solar flare most probably produced 10 GeV protons; these could not be observed at Earth, as theit was an east limb event.

  13. PRELIMINARY EVALUATION OF DWPF IMPACTS OF BORIC ACID USE IN CESIUM STRIP FOR SWPF AND MCU

    SciTech Connect

    Stone, M.

    2010-09-28

    A new solvent system is being evaluated for use in the Modular Caustic-Side Solvent Extraction Unit (MCU) and in the Salt Waste Processing Facility (SWPF). The new system includes the option to replace the current dilute nitric acid strip solution with boric acid. To support this effort, the impact of using 0.01M, 0.1M, 0.25M and 0.5M boric acid in place of 0.001M nitric acid was evaluated for impacts on the DWPF facility. The evaluation only covered the impacts of boric acid in the strip effluent and does not address the other changes in solvents (i.e., the new extractant, called MaxCalix, or the new suppressor, guanidine). Boric acid additions may lead to increased hydrogen generation during the SRAT and SME cycles as well as change the rheological properties of the feed. The boron in the strip effluent will impact glass composition and could require each SME batch to be trimmed with boric acid to account for any changes in the boron from strip effluent additions. Addition of boron with the strip effluent will require changes in the frit composition and could lead to changes in melt behavior. The severity of the impacts from the boric acid additions is dependent on the amount of boric acid added by the strip effluent. The use of 0.1M or higher concentrations of boric acid in the strip effluent was found to significantly impact DWPF operations while the impact of 0.01M boric acid is expected to be relatively minor. Experimental testing is required to resolve the issues identified during the preliminary evaluation. The issues to be addressed by the testing are: (1) Impact on SRAT acid addition and hydrogen generation; (2) Impact on melter feed rheology; (3) Impact on glass composition control; (4) Impact on frit production; and (5) Impact on melter offgas. A new solvent system is being evaluated for use in the Modular Caustic-Side Solvent Extraction Unit (MCU) and in the Salt Waste Processing Facility (SWPF). The new system includes the option to replace the

  14. Development and preliminary evaluation of a particulate matter emission factor model for European motor vehicles.

    PubMed

    Singh, R B; Colls, J J

    2000-10-01

    Although modeling of gaseous emissions from motor vehicles is now quite advanced, prediction of particulate emissions is still at an unsophisticated stage. Emission factors for gasoline vehicles are not reliably available, since gasoline vehicles are not included in the European Union (EU) emission test procedure. Regarding diesel vehicles, emission factors are available for different driving cycles but give little information about change of emissions with speed or engine load. We have developed size-specific speed-dependent emission factors for gasoline and diesel vehicles. Other vehicle-generated emission factors are also considered and the empirical equation for re-entrained road dust is modified to include humidity effects. A methodology is proposed to calculate modal (accelerating, cruising, or idling) emission factors. The emission factors cover particle size ranges up to 10 microns, either from published data or from user-defined size distributions. A particulate matter emission factor model (PMFAC), which incorporates virtually all the available information on particulate emissions for European motor vehicles, has been developed. PMFAC calculates the emission factors for five particle size ranges [i.e., total suspended particulates (TSP), PM10, PM5, PM2.5, and PM1] from both vehicle exhaust and nonexhaust emissions, such as tire wear, brake wear, and re-entrained road dust. The model can be used for an unlimited number of roads and lanes, and to calculate emission factors near an intersection in user-defined elements of the lane. PMFAC can be used for a variety of fleet structures. Hot emission factors at the user-defined speed can be calculated for individual vehicles, along with relative cold-to-hot emission factors. The model accounts for the proportions of distance driven with cold engines as a function of ambient temperature and road type (i.e., urban, rural, or motorway). A preliminary evaluation of PMFAC with an available dispersion model to predict

  15. Preliminary Evaluations of Polymer-based Lithium Battery Electrolytes Under Development for the Polymer Electrolyte Rechargeable Systems Program

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.; Bennett, William R.

    2003-01-01

    A component screening facility has been established at The NASA Glenn Research Center (GRC) to evaluate candidate materials for next generation, lithium-based, polymer electrolyte batteries for aerospace applications. Procedures have been implemented to provide standardized measurements of critical electrolyte properties. These include ionic conductivity, electronic resistivity, electrochemical stability window, cation transference number, salt diffusion coefficient and lithium plating efficiency. Preliminary results for poly(ethy1ene oxide)-based polymer electrolyte and commercial liquid electrolyte are presented.

  16. Evaluation of Liver Stiffness After Radioembolization by Real-Time ShearWave™ Elastography: Preliminary Study

    SciTech Connect

    Bas, Ahmet; Samanci, Cesur; Gulsen, Fatih Cantasdemir, Murat; Kabasakal, Levent; Kantarci, Fatih; Numan, Furuzan

    2015-08-15

    PurposeTo evaluate the effect of ShearWave™ elastography (SWE) for the assessment of liver fibrosis after radioembolization (RE) in patients with liver malignancies.Materials and MethodsWe prospectively examined the effects of SWE before and after RE in 17 adult patients, from June 2012 to September 2013. All patients underwent SWE within 1 month before and 3 months (96.3 ± 22.9 days) after RE. Measurements were taken in segments III, IV, V, and VI (lateral/medial left lobe and anterior/posterior right lobe, respectively). Liver stiffness was studied in the 39 treated segments.ResultsThe mean stiffness of liver tissue according to the pre-RE SWE measurements was not different from the post-RE SWE measurements in the segments that did not undergo RE. Conversely, segments treated with RE were significantly stiffer according to the post-RE SWE measurements (mean SWE 17.4 kPa) than according to the baseline measurements (7.0 kPa) (p < 0.001). Patients with hepatocellular carcinoma and preexisting infection with hepatitis B and C viruses had higher pre-embolization stiffness, and the post-embolization stiffness of the treated segments in these patients was higher than that in the remainder of the study population.ConclusionThese data suggest that SWE measurements of liver stiffness increase as early as the third month after RE. SWE could be used as a noninvasive complementary imaging method for preliminary assessment of liver fibrosis before and after RE.

  17. Transport analysis of measured neutron leakage spectra from spheres as tests of evaluated high energy cross sections

    NASA Technical Reports Server (NTRS)

    Bogart, D. D.; Shook, D. F.; Fieno, D.

    1973-01-01

    Integral tests of evaluated ENDF/B high-energy cross sections have been made by comparing measured and calculated neutron leakage flux spectra from spheres of various materials. An Am-Be (alpha,n) source was used to provide fast neutrons at the center of the test spheres of Be, CH2, Pb, Nb, Mo, Ta, and W. The absolute leakage flux spectra were measured in the energy range 0.5 to 12 MeV using a calibrated NE213 liquid scintillator neutron spectrometer. Absolute calculations of the spectra were made using version 3 ENDF/B cross sections and an S sub n discrete ordinates multigroup transport code. Generally excellent agreement was obtained for Be, CH2, Pb, and Mo, and good agreement was observed for Nb although discrepancies were observed for some energy ranges. Poor comparative results, obtained for Ta and W, are attributed to unsatisfactory nonelastic cross sections. The experimental sphere leakage flux spectra are tabulated and serve as possible benchmarks for these elements against which reevaluated cross sections may be tested.

  18. Evaluation of two-stage system for neutron measurement aiming at increase in count rate at Japan Atomic Energy Agency-Fusion Neutronics Source

    SciTech Connect

    Shinohara, K. Ochiai, K.; Sukegawa, A.; Ishii, K.; Kitajima, S.; Baba, M.; Sasao, M.

    2014-11-15

    In order to increase the count rate capability of a neutron detection system as a whole, we propose a multi-stage neutron detection system. Experiments to test the effectiveness of this concept were carried out on Fusion Neutronics Source. Comparing four configurations of alignment, it was found that the influence of an anterior stage on a posterior stage was negligible for the pulse height distribution. The two-stage system using 25 mm thickness scintillator was about 1.65 times the count rate capability of a single detector system for d-D neutrons and was about 1.8 times the count rate capability for d-T neutrons. The results suggested that the concept of a multi-stage detection system will work in practice.

  19. The evaluation of neutron and gamma ray dose equivalent distributions in patients and the effectiveness of shield materials for high energy photons radiotherapy facilities.

    PubMed

    Ghassoun, J; Senhou, N

    2012-04-01

    In this study, the MCNP5 code was used to model radiotherapy room of a medical linear accelerator operating at 18 MV and to evaluate the neutron and the secondary gamma ray fluences, the energy spectra and the dose equivalent distributions inside a liquid tissue-equivalent (TE) phantom. The obtained results were compared with measured data published in the literature. Moreover, the shielding effects of various neutron material shields on the radiotherapy room wall were also investigated. Our simulation results showed that paraffin wax containing boron carbide presents enough effectiveness to reduce both neutron and secondary gamma ray doses.

  20. Formulation and experimental evaluation of closed-form control laws for the rapid maneuvering of reactor neutronic power

    SciTech Connect

    Bernard, J.A. . Nuclear Reactor Lab.)

    1989-09-01

    This report describes both the theoretical development and the experimental evaluation of a novel, robust methodology for the time-optimal adjustment of a reactor's neutronic power under conditions of closed-loop digital control. Central to the approach are the MIT-SNL Period-Generated Minimum Time Control Laws' which determine the rate at which reactivity should be changed in order to cause a reactor's neutronic power to conform to a specified trajectory. Using these laws, reactor power can be safely raised by five to seven orders of magnitude in a few seconds. The MIT-SNL laws were developed to facilitate rapid increases of neutronic power on spacecraft reactors operating in an SDI environment. However, these laws are generic and have other applications including the rapid recovery of research and test reactors subsequent to an unanticipated shutdown, power increases following the achievement of criticality on commercial reactors, power adjustments on commercial reactors so as to minimize thermal stress, and automated startups. The work reported here was performed by the Massachusetts Institute of Technology under contract to the Sandia National Laboratories. Support was also provided by the US Department of Energy's Division of University and Industry Programs. The work described in this report is significant in that a novel solution to the problem of time-optimal control of neutronic power was identified, in that a rigorous description of a reactor's dynamics was derived in that the rate of change of reactivity was recognized as the proper control signal, and in that extensive experimental trials were conducted of these newly developed concepts on actual nuclear reactors. 43 refs., 118 figs., 11 tabs.

  1. Coupled neutronics and thermal-hydraulics numerical simulations of a Molten Fast Salt Reactor (MFSR)

    NASA Astrophysics Data System (ADS)

    Laureau, A.; Rubiolo, P. R.; Heuer, D.; Merle-Lucotte, E.; Brovchenko, M.

    2014-06-01

    Coupled neutronics and thermalhydraulic numerical analyses of a molten salt fast reactor are presented. These preliminary numerical simulations are carried-out using the Monte Carlo code MCNP and the Computation Fluid Dynamic code OpenFOAM. The main objectives of this analysis performed at steady-reactor conditions are to confirm the acceptability of the current neutronic and thermalhydraulic designs of the reactor, to study the effects of the reactor operating conditions on some of the key MSFR design parameters such as the temperature peaking factor. The effects of the precursor's motion on the reactor safety parameters such as the effective fraction of delayed neutrons have been evaluated.

  2. Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C

    SciTech Connect

    Chadwick, M.B.; Blann, M.; Cox, L.; Young, P.G.; Meigooni, A.

    1995-04-11

    A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements where they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A{le}and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV.

  3. Elastic incoherent neutron scattering on systems of biophysical interest: mean square displacement evaluation from self-distribution function.

    PubMed

    Magazù, Salvatore; Maisano, Giacomo; Migliardo, Federica; Benedetto, Antonio

    2008-07-31

    In the present work an operational recipe for the mean square displacement (MSD) determination, highlighting the connection between the self-distribution function and average statistical values, is presented. The determination of the MSD and of its contributions associated with different mechanisms, together with their thermal behavior, is performed by evaluating the self-distribution function derived by elastic incoherent neutron scattering (EINS). The approach is tested on EINS data collected by the backscattering spectrometer IN13 (ILL, Grenoble, France) on two model systems such as dry myoglobin in trehalose and poly(ethylene glycol) with mean molecular weight M(w) = 400 (PEG 400).

  4. R-Matrix Evaluation of Cl Neutron Cross Sections up to 1.2 MeV

    SciTech Connect

    Sayer, R.O.

    2003-03-27

    We have performed an evaluation of {sup 35}Cl, {sup 37}Cl, and {sup nat}Cl neutron cross sections in the resolved resonance region with the multilevel Reich-Moore R-matrix formalism. Resonance analyses were carried out with the computer code SAMMY, which utilizes Bayes' method, a generalized least squares technique. A recent modification of SAMMY enabled us to calculate charged particle penetrabilities for the proton exit channel. Our resonance parameter representation describes the data much better than does ENDF/B-VI, and it should lead to improved criticality safety calculations for systems where Cl is present.

  5. Preliminary 3D In-situ measurements of the texture evolution of strained H2O ice during annealing using neutron Laue diffractometry

    NASA Astrophysics Data System (ADS)

    Journaux, Baptiste; Montagnat, Maurine; Chauve, Thomas; Ouladdiaf, Bachir; Allibon, John

    2015-04-01

    Dynamic recrystallization (DRX) strongly affects the evolution of microstructure (grain size and shape) and texture (crystal preferred orientation) in materials during deformation at high temperature. Since texturing leads to anisotropic physical properties, predicting the effect of DRX is essential for industrial applications, for interpreting geophysical data and modeling geodynamic flows, and predicting ice sheet flow and climate evolution. A large amount of literature is available related to metallurgy, geology or glaciology, but there remains overall fundamental questions about the relationship between nucleation, grain boundary migration and texture development at the microscopic scale. Previous measurements of DRX in ice were either conducted using 2D ex-situ techniques such as AITA [1,2] or Electron Backscattering Diffraction (EBSD) [3], or using 3D statistical ex-situ [4] or in-situ [5] techniques. Nevertheless, all these techniques failed to observe at the scale of nucleation processes during DRX in full 3D. Here we present a new approach using neutron Laue diffraction, which enable to perform 3D measurements of in-situ texture evolution of strained polycrystalline H2O ice (>2% at 266 K) during annealing at the microscopic scale. Thanks the CYCLOPS instrument [6] (Institut Laue Langevin Grenoble, France) and the intrinsic low background of this setup, preliminary observations enabled us to follow, in H2O ice, the evolution of serrated grain boundaries, and kink-band during annealing. Our observations show a significant evolution of the texture and internal misorientation over the course of few hours at an annealing temperature of 268.5 K. In the contrary, ice kink-band structures seem to be very stable over time at near melting temperatures. The same samples have been analyzed ex-situ using EBSD for comparison. These results represent a first step toward in-situ microscopic measurements of dynamic recrystallization processes in ice during strain. This

  6. Root strength evaluation on vineyards in an area susceptible to shallow landslides: preliminary results

    NASA Astrophysics Data System (ADS)

    Meisina, Claudia; Bordoni, Massimiliano; Vercesi, Alberto; Vergani, Chiara; Bassanelli, Chiara; Zizioli, Davide; Valentino, Roberto; Bittelli, Marco; Chersich, Silvia

    2014-05-01

    The role played by plant roots in reinforcing mechanically the soil is widely recognized and numerous studies were carried out in the last years for the quantification of the effect of vegetation on slope stability, especially in terms of root reinforcement. Vegetation can represent an effective instrument to decrease landslides susceptibility, in particular towards shallow landslides, which usually develop in the first 2 meters from the ground level where the majority of plant roots develop. In this work preliminary results of root reinforcement on vineyards located in an area susceptible to shallow landslides are presented. Vineyards have been chosen because there are no studies about the role played by vineyards roots on soil cohesion and because they represent the most common species in the studied area. The objectives of the study were i) to estimate the root strength through laboratory tests on sampled roots of living vine plants, ii) to analyze the distribution pattern of roots of living plants in the soil profile, iii) to assess the root contribution to soil cohesion on the basis of the measured root strength and the distribution pattern of the roots evaluated trough in-situ surveys. The sample study area is in the north-eastern part of Oltrepo Pavese, in northern Italy. In this area, hilly slopes are extensively cultivated with vineyards for the production of wine. In April 2009, this sector of Oltrepo Pavese experienced a great rainfall event, which triggered more than 1600 shallow landslides in an area of about 250 km2. In particular, a great number of these phenomena affected slopes cultivated with vineyards that were completely or partially destroyed with consequent serious economic losses. Roots for mechanical properties evaluation were collected from pits in different test-site slopes characterized by vineyards of the same installation age (about 10-20 years). In correspondence of these pits the distribution pattern of the living roots with depth was

  7. Preliminary evaluation of a membrane-based system for removing CO2 from air

    NASA Technical Reports Server (NTRS)

    Mccray, Scott B.; Wytcherley, Randi W.; Friesen, Dwayne T.; Ray, Rod J.

    1990-01-01

    Processes to remove and/or recover CO2 from air are essential to the long-term success of the U.S. space program. The results of a preliminary investigation of the use of a novel membrane-based system for removal of CO2 from air are presented. Features of this technology that make it attractive include the following: (1) it is lightweight; (2) it requires no consumables or expendables; (3) it is relatively simple; and (4) it does not rely directly on other subsystems. Preliminary designs of systems for removing CO2 from spacecraft cabin atmospheres and from the extravehicular mobility unit are presented.

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

    SciTech Connect

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

    1993-07-01

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

  9. Mean square displacement evaluation by elastic neutron scattering self-distribution function.

    PubMed

    Magazù, Salvatore; Maisano, Giacomo; Migliardo, Federica; Benedetto, Antonio

    2008-06-01

    In the present work an operational recipe for the mean square displacement (MSD) determination, highlighting the connection between elastic incoherent neutron scattering (EINS) intensity profiles and the associated self-distribution function, is presented. The determination of the thermal behavior of the total MSD and of its partial contributions is tested on EINS data collected by the backscattering spectrometer IN13 (ILL, Grenoble) on a model system such as PolyEthylene Glycol with a mean molecular weight of 400 Dalton (PEG 400).

  10. Evaluation of a neutron-photon shield for transuranic (TRU) waste containers

    SciTech Connect

    Wishau, R. J.; Gallegos, M.; Ruby, R.; Sullivan, E. J.

    2004-01-01

    The Los Alamos National Laboratory (LANL) Operational Health Physics Group, with the support of the Nuclear Materials Technology Waste Management Group, has developed a wrap-around shield for use with 0.208 cubic meter (55 gallon) drums containing transuranic (TRU) waste. The shield or 'drum cover' as it is called, is innovative in its ability to attenuate both neutron and photon radiation associated with TRU waste. This poster presents information on the design, fabrication and field use of the drum cover. Design details to be presented include the composition of the shield including the materials used, thicknesses, weight, dimensions and fastener arrangement. Information on the source supplier for the shield materials, the fabrication vendor and the drum cover cost are provided. Shielding data show the unique effectiveness of the drum cover and its ability to reduce neutron and photon radiation exposures as low as reasonably achievable (ALARA). These data include x-ray testing of the assembled shield materials, as well as field experience report on the drum cover using TRU waste containers and neutron source drums. The poster includes discussion and photographs of recent field uses for the drum cover, user experience and acceptance of the drum cover and suggestions for future use and enhancement of the drum cover design.

  11. Development and Preliminary Evaluation of a One-Week Summer Treatment Program for Separation Anxiety Disorder

    ERIC Educational Resources Information Center

    Santucci, Lauren C.; Ehrenreich, Jill T.; Trosper, Sarah E.; Bennett, Shannon M.; Pincus, Donna B.

    2009-01-01

    Numerous clinical trials have demonstrated the efficacy of cognitive behavior therapy (CBT) for the treatment of childhood Separation Anxiety Disorder (SAD) and other anxiety disorders yet additional research may still be needed to better access and engage anxious youth. In this study, we investigated the acceptability and preliminary utility of a…

  12. Evaluation of gratings for X-ray and neutron phase imaging techniques by using x-ray projection microscope

    SciTech Connect

    Minami, Katsunori; Yashiro, Wataru; Olbinado, Margie; Momose, Atsushi

    2012-07-31

    In the X-ray and neutron Talbot (-Lau) interferometry, fabrication of phase or amplitude grating with a high-aspect ratio is a key factor to obtain high quality images. To improve the ability of the grating, evaluation of shape and thickness variation and feed-back to the fabrication process are essential. Here, it is shown that X-ray projection microscope with a spatial resolution of sub-micrometer is a powerful tool for the purpose. Three kinds of gratings have been evaluated by using a projection X-ray microscope with X-ray source size of 0.6 micrometer. Uniformity of thickness of the grating has been visualized nondestructively.

  13. Bruyères-le-Châtel Neutron Evaluations of Actinides with the TALYS Code: The Fission Channel

    NASA Astrophysics Data System (ADS)

    Romain, P.; Morillon, B.; Duarte, H.

    2016-01-01

    For several years, various neutron evaluations of plutonium and uranium isotopes have been performed at Bruyères-le-Châtel (BRC), from 1 keV up to 30 MeV. Since only nuclear reaction models have been used to produce these evaluations, our approach was named the "Full Model" approach. Total, shape elastic and direct inelastic cross sections were obtained from the coupled channels model using a dispersive optical potential developed for actinides, with a large enough coupling scheme including the lowest octupolar band. All other cross sections were calculated using the Hauser-Feshbach theory (TALYS code) with a pre-equilibrium component above 8-10 MeV. In this paper, we focus our attention on the fission channel. More precisely, we will present the BRC contribution to fission modeling and the philosophy adopted in our "Full Model" approach. Performing evaluations with the "Full Model" approach implies the optimization of a large number of model parameters. With increasing neutron incident energy, many residual nuclei produced by nucleon emission also lead to fission. All available experimental data assigned to various fission mechanisms of the same nucleus were used to determine fission barrier parameters. For uranium isotopes, triple-humped fission barriers were required in order to reproduce accurately variations of the experimental fission cross sections. Our BRC fission modeling has shown that the effects of the class II or class III states located in the wells of the fission barrier sometimes provide an anti-resonant transmission rather than a resonant one. Consistent evaluations were produced for a large series of U and Pu isotopes. Resulting files were tested against integral data.

  14. Preliminary time-of-flight neutron diffraction studies of Escherichia coli ABC transport receptor phosphate-binding protein at the Protein Crystallography Station

    PubMed Central

    Sippel, K. H.; Bacik, J.; Quiocho, F. A.; Fisher, S. Z.

    2014-01-01

    Inorganic phosphate is an essential molecule for all known life. Organisms have developed many mechanisms to ensure an adequate supply, even in low-phosphate conditions. In prokaryotes phosphate transport is instigated by the phosphate-binding protein (PBP), the initial receptor for the ATP-binding cassette (ABC) phosphate transporter. In the crystal structure of the PBP–phosphate complex, the phosphate is completely desolvated and sequestered in a deep cleft and is bound by 13 hydrogen bonds: 12 to protein NH and OH donor groups and one to a carboxylate acceptor group. The carboxylate plays a key recognition role by accepting a phosphate hydrogen. PBP phosphate affinity is relatively consistent across a broad pH range, indicating the capacity to bind monobasic (H2PO4 −) and dibasic (HPO4 2−) phosphate; however, the mechanism by which it might accommodate the second hydrogen of monobasic phosphate is unclear. To answer this question, neutron diffraction studies were initiated. Large single crystals with a volume of 8 mm3 were grown and subjected to hydrogen/deuterium exchange. A 2.5 Å resolution data set was collected on the Protein Crystallography Station at the Los Alamos Neutron Science Center. Initial refinement of the neutron data shows significant nuclear density, and refinement is ongoing. This is the first report of a neutron study from this superfamily. PMID:24915101

  15. Evaluation of homogeneity of a certified reference material by instrumental neutron activation analysis

    SciTech Connect

    Kratochvil, B.; Duke, M.J.M.; Ng, D.

    1986-01-01

    The homogeneity of the marine reference material TORT-1, a spray-dried and acetone-extracted hepatopancreatic material from the lobster, was tested for 26 elements by instrumental neutron activation analysis (INAA). Through a one-way analysis of variance based on six analyses on each of six bottles of TORT-1, it was concluded that the between-bottle heterogeneity is no greater than the within-bottle heterogeneity. The analytical results for those elements for which values were provided by NRC agree with the NRC values within 95% confidence limits. 8 references, 6 tables.

  16. Design, synthesis and preliminary biological evaluation of indoline-2,3-dione derivatives as novel HDAC inhibitors.

    PubMed

    Jin, Kang; Li, Shanshan; Li, Xiaoguang; Zhang, Jian; Xu, Wenfang; Li, Xuechen

    2015-08-01

    Histone deacetylases (HDACs) are zinc-dependent or NAD(+) dependent enzymes and play a critical role in the process of tumor development. Herein a series of indoline-2,3-dione derivatives have been designed and synthesized as potential HDACs inhibitors. The preliminary biological evaluation showed that most compounds synthesized have exhibited moderate Hela cell nuclear extract inhibitory activities, among which compound 25a (IC50=10.13 nM) has shown the best efficacy. The anti-proliferative activities of some of these compounds were also discussed. PMID:26100440

  17. Expect respect support groups: preliminary evaluation of a dating violence prevention program for at-risk youth.

    PubMed

    Ball, Barbara; Tharp, Andra Teten; Noonan, Rita K; Valle, Linda Anne; Hamburger, Merle E; Rosenbluth, Barri

    2012-07-01

    Expect Respect support groups, a selective prevention strategy, are designed to prevent and reduce dating violence among at-risk middle and high school students. This preliminary, uncontrolled evaluation examined changes in healthy relationship skills and emotionally and physically abusive behaviors in participants' peer and dating relationships. Self-reports (N = 144) showed significant increases in healthy relationship skills from baseline to program completion, whereas levels of victimization and perpetration remained unchanged. A subgroup of students who reported baseline levels of victimization and perpetration with means at least one standard deviation above the group mean reported significantly less victimization and perpetration at program completion. PMID:22872708

  18. Preliminary volcanic hazards evaluation for Los Alamos National Laboratory Facilities and Operations : current state of knowledge and proposed path forward

    SciTech Connect

    Keating, Gordon N.; Schultz-Fellenz, Emily S.; Miller, Elizabeth D.

    2010-09-01

    The integration of available information on the volcanic history of the region surrounding Los Alamos National Laboratory indicates that the Laboratory is at risk from volcanic hazards. Volcanism in the vicinity of the Laboratory is unlikely within the lifetime of the facility (ca. 50–100 years) but cannot be ruled out. This evaluation provides a preliminary estimate of recurrence rates for volcanic activity. If further assessment of the hazard is deemed beneficial to reduce risk uncertainty, the next step would be to convene a formal probabilistic volcanic hazards assessment.

  19. Evaluation of the characteristics of the neutron reference field using D2O-moderated 252Cf source.

    PubMed

    Kowatari, M; Fujii, K; Takahashi, M; Yoshizawa, M; Shimizu, S; Kawasaki, K; Yamaguchi, Y

    2007-01-01

    The ambient/personal dose equivalent per fluence for D(2)O moderated (252)Cf neutron source was determined by measurement. An appropriate subtraction of the scattered neutrons is required for the accurate measurement of direct neutrons. A cubic shadow object was used for the subtraction of the scattered neutrons from the surroundings. The scattered neutrons to be subtracted vary with the position of the shadow object due to the large volume of the source. Using the Monte Carlo code MCNP-4C, the optimum positions of the shadow object were surveyed for subtracting the scattered neutrons. The energy spectra of direct neutrons were measured in the optimum position. The dosimetric parameters for the D(2)O moderated (252)Cf neutron source were reasonable, taking into account the uncertainties of the parameters.

  20. Neutron Dosimetry on the Full-Core First Generation VVER-440 Aimed at Reactor Support Structure Load Evaluation

    NASA Astrophysics Data System (ADS)

    Borodkin, P.; Borodkin, G.; Khrennikov, N.; Konheiser, J.; Noack, K.

    2009-08-01

    Reactor support structures (RSS), especially the ferritic steel wall of the water tank, of first-generation VVER-440 are non-restorable reactor equipment, and their lifetime may restrict plant-life. All operated Russian first generation VVER-440 have a reduced core with dummy assemblies except Unit 4 of Novovoronezh nuclear power plant (NPP). In comparison with other reactors, the full-core loading scheme of this reactor provides the highest neutron fluence on the reactor pressure vessel (RPV) and RSS accumulated over design service-life and its prolongation. The radiation load parameters on the RPV and RSS that have resulted from this core loading scheme should be evaluated by means of precise calculations and validated by ex-vessel neutron dosimetry to provide the reliable assessment of embrittlement parameters of these reactor components. The results of different types of calculations and their comparison with measured data have been analyzed in this paper. The calculational analysis of RSS fluence rate variation in dependence on the core loading scheme, including the standard and low leakage core as well as the introduction of dummy assemblies, is presented in this paper.

  1. Fast and simple method for Goss texture evaluation by neutron diffraction

    NASA Astrophysics Data System (ADS)

    Kucerakova, M.; Kolařík, K.; Čapek, J.; Vratislav, S.; Kalvoda, L.

    2016-09-01

    Requirement of low power losses is one of the crucial demands laid on properties of electric steel sheets used in construction of various magnetic circuits. For cold-rolled grain- oriented (CRGO) Fe-3%Si sheets used in majority of power distribution transformers, the Goss texture {110}<001> is known to provide the best utility properties (low power loses, high magnetic permeability). Due to the coarse grain size of CRGO steel, neutron diffraction (ND) is dominantly used to characterize the sheets' texture in order to achieve statistically significant data. In this paper, we present a fast and simple method for characterization of Goss texture perfection level in CRGO steel sheets based on monochromatic ND. The method is tested on 8 samples differing in fabrication technology and magnetic properties. Satisfactory performance of the method and its suitability for a detail texture analyses is tested by juxtaposition of the obtained textural and the magnetic characteristics measured by Barkhausen method.

  2. Evaluation of liquid behavior in a Variable Conductance Heat Pipe by neutron radiography

    NASA Astrophysics Data System (ADS)

    Sugimoto, K.; Asano, H.; Murakawa, H.; Takenaka, N.; Nagayasu, T.; Ipposhi, S.

    2011-09-01

    A Variable Conductance Heat Pipe (VCHP) is used as a cooling device for electrical equipments. The condensation area is passively controlled by the non-condensable gas volume in the VCHP depending on the heat load. The VCHP has often a bent pipe between the evaporation and condensation area. The heat pipe performance depends much on the bent pipe shape and configuration because a liquid plug is formed in the bent pipe and disturbs the refrigerant circulation. However, the mechanism has not been clarified well. The neutron radiography system at the JRR-3 in Japan Atomic Energy Agency (JAEA) was used to visualize the refrigerant behavior in the VCHP. Effects of the thin plate inserted in the pipe, refrigerant filling ratios and heat pipe configuration were examined on the heat pipe performance. The liquid plug was formed at the bend and caused to decrease the performance. It was confirmed that the thin plate insert was effective to disturb the liquid plug formation.

  3. Abstract for Guide coating and evaluation techniques for Ultracold Neutron transport

    NASA Astrophysics Data System (ADS)

    Ding, Xinjian; UCNA Collaboration

    2013-10-01

    UCN are produced by cold neutron flux down-scattering in a solid deuterium source in Area B of Los Alamos National Laboratory and then transported to the experimental decay volume of the UCNA experiment and to other UCN experiments through a sequence of guide tubes. These tubes are coated with diamond-like carbon (DLC) films to maintain UCN polarization and maximize material potential. We will briefly review the UCNA guide system, the requirements for UCNA guides, and the pulsed-laser deposition (PLD) process we use to produce diamond-like carbon (DLC) films. There will be a discussion of some new analysis techniques for both in situ PLD coating and surface structure of the DLC film that are utilized in the UCN experiments. We will present both present and future research and development in UCN guide coating techniques and materials. UCNA Collaboration group.

  4. PRELIMINARY EVALUATION OF LANDSAT-4 THEMATIC MAPPER DATA FOR THEIR GEOMETRIC AND RADIOMETRIC ACCURACIES.

    USGS Publications Warehouse

    Podwysoki, M.H.; Falcone, N.; Bender, L.U.; Jones, O.D.; ,

    1985-01-01

    This report describes results of some preliminary analyses of Landsat-4 Thematic Mapper data for the NASA Landsat Image Quality Analysis program. The work is being done under interagency agreement S-12407-C between the U. S. Geological Survey and NASA-Goddard Space Flight Center. Landsat-4 TM scenes for Washington, D. C. Macon, Georgia (40050-15333, September 4, 1982) and Cape Canaveral, Florida have been examined to determine their geometric and radiometric accuracy. In addition, parts of these scenes are also being analyzed to determine the ability to identify specific rock types with the added near-infrared TM bands.

  5. Preliminary In Vivo Evaluation of a Hybrid Armored Vascular Graft Combining Electrospinning and Additive Manufacturing Techniques.

    PubMed

    Spadaccio, Cristiano; Nappi, Francesco; De Marco, Federico; Sedati, Pietro; Sutherland, Fraser W H; Chello, Massimo; Trombetta, Marcella; Rainer, Alberto

    2016-01-01

    In this study, we tested in vivo effectiveness of a previously developed poly-l-lactide/poly-ε-caprolactone armored vascular graft releasing heparin. This bioprosthesis was designed in order to overcome the main drawbacks of tissue-engineered vascular grafts, mainly concerning poor mechanical properties, thrombogenicity, and endothelialization. The bioprosthesis was successfully implanted in an aortic vascular reconstruction model in rabbits. All grafts implanted were patent at four weeks postoperatively and have been adequately populated by endogenous cells without signs of thrombosis or structural failure and with no need of antiplatelet therapy. The results of this preliminary study might warrant for further larger controlled in vivo studies to further confirm these findings.

  6. UAS Integration into the NAS: iHTL: DAA Display Evaluation Preliminary Results

    NASA Technical Reports Server (NTRS)

    Fern, Lisa; Rorie, Conrad; Shively, Jay

    2014-01-01

    The integrated human-in-the-loop (iHITL) simulation examined the effect of four different Detect-and-Avoid (DAA) display concepts on unmanned aircraft system (UAS) pilots' ability to maintain safe separation. The displays varied in the type and amount of guidance they provided to pilots. The study's background and methodology are discussed, followed by a presentation of the preliminary 'measured response' data (i.e., pilots' end-to-end response time in reacting to traffic alerts on their DAA display). Results indicate that display type had moderate to no affect on pilot measured response times.

  7. Preliminary economic evaluation of the use of graphite composite materials in surface transportation, phase 1 results

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Composite materials are discussed with emphasis on the identification of the characteristics of those materials that make them attractive for use in surface transportation. Potential uses of graphite composites are given including automotive applications and the effects of materials substitution on vehicle characteristics and performance. Preliminary estimates of the economic effects of the use of graphite composite materials on vehicle manufacturers and consumers are included. The combined impact on the national economy of vehicle design changes to meet mandated fuel efficiency requirements and the extensive use of graphite composite materials in the automotive industry is considered.

  8. Preliminary neutron and ultrahigh-resolution X-ray diffraction studies of the aspartic proteinase endothiapepsin cocrystallized with a gem-diol inhibitor

    SciTech Connect

    Tuan, Han-Fang; Erskine, Peter; Langan, Paul; Cooper, Jon; Coates, Leighton

    2007-12-01

    Three data sets have been collected on endothiapepsin complexed with the gem-diol inhibitor PD-135,040: a high-resolution synchrotron X-ray data set, a room-temperature X-ray data set and a neutron diffraction data set. Until recently, it has been impossible to grow large protein crystals of endothiapepsin with any gem-diol inhibitor that are suitable for neutron diffraction. Endothiapepsin has been cocrystallized with the gem-diol inhibitor PD-135,040 in a low solvent-content (39%) unit cell, which is unprecedented for this enzyme–inhibitor complex and enables ultrahigh-resolution (1.0 Å) X-ray diffraction data to be collected. This atomic resolution X-ray data set will be used to deduce the protonation states of the catalytic aspartate residues. A room-temperature neutron data set has also been collected for joint refinement with a room-temperature X-ray data set in order to locate the H/D atoms at the active site.

  9. Evaluated Nuclear Data Library for Transport Calculations Involving Incident Neutrons and Protons of Energy Up to 100 MeV.

    1993-08-09

    Version 00 This data base was developed for use in Monte Carlo or discrete ordinate transport codes, for example, the general Monte Carlo code MCNP. Various modules of the NJOY processing code system have been enhanced to permit processing of the ENDF/B-VI formatted evaluations into both continuous-energy and multi-group format. The transport data files for all 18 projectile-plus-target systems have been processed through NJOY, and coupled multi-particle, multi-group transport libraries for MCNP now exist. Inmore » addition, pointwise MCNP libraries to 100 MeV for incident neutrons have been prepared for the nine targets. The production version of the MCNP code is being modified to handle the new pointwise libraries. The production version of MCNP already supports the use of coupled multi-group libraries.« less

  10. A Preliminary Guide for Conducting Naturalistic Evaluation in Studying Museum Environment.

    ERIC Educational Resources Information Center

    Wolf, Robert L.; Tymitz, Barbara L.

    This document presents guidelines for use by museum staff members as they evaluate their institutional capabilities and programs. Guidelines are based on a new evaluation perspective--naturalistic evaluation--which can help museum staff assess their programs in a more interpretative, less judgmental way. Naturalistic evaluation is characterized by…

  11. Evaluated 182,183,184,186W Neutron Cross Sections and Covariances in the Resolved Resonance Region

    SciTech Connect

    Pigni, Marco T; Leal, Luiz C

    2015-01-01

    Oak Ridge National Laboratory (ORNL) has recently completed the resonance parameter evaluation of four tungsten isotopes, i.e., 182,183,184,186W, in the neutron energy range of thermal up to several keV. This nuclear data work was performed with support from the US Nuclear Criticality Safety Program (NCSP) in an effort to provide improved tungsten cross section and covariance data for criticality safety analyses. The evaluation methodology uses the Reich-Moore approximation of the R-matrix formalism of the code SAMMY to fit high-resolution measurements performed in 2010 and 2012 at the Geel linear accelerator facility (GELINA), as well as other experimental data sets on natural tungsten available in the EXFOR library. In the analyzed energy range, this work nearly doubles the resolved resonance region (RRR) present in the latest US nuclear data library ENDF/B-VII.1. In view of the interest in tungsten for distinct types of nuclear applications and the relatively homogeneous distribution of the isotopic tungsten—namely, 182W(26.5%), 183W(14.31%), 184W(30.64%), and 186W(28.43%) - the completion of these four evaluations represents a significant contribution to the improvement of the ENDF library. This paper presents an overview of the evaluated resonance parameters and related covariances for total and capture cross sections on the four tungsten isotopes.

  12. Seismic Evaluation and Preliminary Design of Regular Setback Masonry Infilled Open Ground Storey RC Frame

    NASA Astrophysics Data System (ADS)

    Hashmi, Arshad K.

    2016-06-01

    Current seismic code presents certain stringent factors for defining frame as regular and irregular. Thereby these stringent factors only decide the type of analysis (i.e. equivalent static analysis or dynamic analysis) to be done. On the contrary, development of new simplified methods such as pushover analysis can give lateral load capacity of any structure (e.g. regular or irregular frame etc.) easily. Design by iterative procedure with the help of pushover analysis for serviceability requirement (i.e. inter storey drift limitation) provided by present seismic code, can provide an alternative to present practicing procedure. Present paper deals with regular setback frame in combination with vulnerable layout of masonry infill walls over the frame elevation (i.e. probable case of "Vertical Stiffness Irregularities"). Nonlinear time history analysis and Capacity Spectrum Method have been implemented to investigate the seismic performance of these frames. Finally, recently developed preliminary design procedure satisfying the serviceability criterion of inter storey drift limitation has been employed for the preliminary design of these frames.

  13. Radiological evaluation of the Cresco system in combination with Osseospeed implants: a preliminary 3-year report

    PubMed Central

    BALDINI, N.; DE SANCTIS, M.; CAGIDIACO, M.C.; BALLERI, P.; VIGNOLETTI, F.; GORACCI, C.; FERRARI, M.

    2014-01-01

    SUMMARY Aim. In this preliminary study, the 3-year radiological outcomes of Osseospeed implant-supported fixed complete or partial prostheses made with two different laboratory protocols were compared. Methods. A convenience sample of 34 patients, who were either partially or completely edentulous in either jaw, were randomly assigned to two groups, of 17 patients each, using either a traditional laboratory protocol (control group) or the Cresco one (test group). The study’s objective was an assessment of marginal bone loss around implants, measured on intraoral radiographs at 3-year follow-up. Results. None of the implants inserted was lost during the study and radiological measurements of marginal bone level changes revealed that the mean marginal bone loss was respectively 0,73±0,33mm for test group and 0,88±1,13mm for control group. The differences between test and control groups were not statistically significant. Conclusion. This preliminary study did not demonstrate statistically significant differences in marginal bone loss around implant-prostheses prepared with the two different laboratory protocols, over the 3-year observational period. PMID:25694796

  14. Preliminary evaluation of biplane correlation (BCI) stereographic imaging for lung nodule detection.

    PubMed

    Boyce, Sarah J; McAdams, H Page; Ravin, Carl E; Patz, Edward F; Washington, Lacey; Martinez, Santiago; Koweek, Lynne; Samei, Ehsan

    2013-02-01

    A biplane correlation (BCI) imaging system obtains images that can be viewed in stereo, thereby minimizing overlapping structures. This study investigated whether using stereoscopic visualization provides superior lung nodule detection compared to standard postero-anterior (PA) image display. Images were acquired at two oblique views of ±3° as well as at a standard PA position from 60 patients. Images were processed using optimal parameters and displayed on a stereoscopic display. The PA image was viewed in the standard format, while the oblique views were paired to provide a stereoscopic view of the subject. A preliminary observer study was performed with four radiologists who viewed and scored the PA image then viewed and scored the BCI stereoscopic image. The BCI stereoscopic viewing of lung nodules resulted in 71 % sensitivity and 0.31 positive predictive value (PPV) index compared to PA results of 86 % sensitivity and 0.26 PPV index. The sensitivity for lung nodule detection with the BCI stereoscopic system was reduced by 15 %; however, the total number of false positives reported was reduced by 35 % resulting in an improved PPV index of 20 %. The preliminary results indicate observer dependency in terms of relative advantage of either system in the detection of lung nodules, but overall equivalency of the two methods with promising potential for BCI as an adjunct diagnostic technique.

  15. Characterization of a Pulse Neutron Source Yield under Field Conditions

    SciTech Connect

    Barzilov, Alexander; Novikov, Ivan; Womble, Phillip C.; Hopper, Lindsay

    2009-03-10

    Technique of rapid evaluation of a pulse neutron sources such as neutron generators under field conditions has been developed. The phoswich sensor and pulse-shape discrimination techniques have been used for the simultaneous measurements of fast neutrons, thermal neutrons, and photons. The sensor has been calibrated using activation neutron detectors and a pulse deuterium-tritium fusion neutron source.

  16. Cast Stone Oxidation Front Evaluation: Preliminary Results For Samples Exposed To Moist Air

    SciTech Connect

    Langton, C. A.; Almond, P. M.

    2013-11-26

    The rate of oxidation is important to the long-term performance of reducing salt waste forms because the solubility of some contaminants, e.g., technetium, is a function of oxidation state. TcO{sub 4}{sup -} in the salt solution is reduced to Tc(IV) and has been shown to react with ingredients in the waste form to precipitate low solubility sulfide and/or oxide phases. Upon exposure to oxygen, the compounds containing Tc(IV) oxidize to the pertechnetate ion, Tc(VII)O{sub 4}{sup -}, which is very soluble. Consequently the rate of technetium oxidation front advancement into a monolith and the technetium leaching profile as a function of depth from an exposed surface are important to waste form performance and ground water concentration predictions. An approach for measuring contaminant oxidation rate (effective contaminant specific oxidation rate) based on leaching of select contaminants of concern is described in this report. In addition, the relationship between reduction capacity and contaminant oxidation is addressed. Chromate (Cr(VI) was used as a non-radioactive surrogate for pertechnetate, Tc(VII), in Cast Stone samples prepared with 5 M Simulant. Cast Stone spiked with pertechnetate was also prepared and tested. Depth discrete subsamples spiked with Cr were cut from Cast Stone exposed to Savannah River Site (SRS) outdoor ambient temperature fluctuations and moist air. Depth discrete subsamples spiked with Tc-99 were cut from Cast Stone exposed to laboratory ambient temperature fluctuations and moist air. Similar conditions are expected to be encountered in the Cast Stone curing container. The leachability of Cr and Tc-99 and the reduction capacities, measured by the Angus-Glasser method, were determined for each subsample as a function of depth from the exposed surface. The results obtained to date were focused on continued method development and are preliminary and apply to the sample composition and curing / exposure conditions described in this report. The

  17. Preliminary Evaluation of the Implementation of a Mentorship Plan in the Faculty of Education at the University of Lleida (UdL), Spain

    ERIC Educational Resources Information Center

    Filella, Gemma; Lara, Isabel; Soldevila, Anna; Nadal, Jesus; Ribes, Ramona; Agullo, Maria Jesus; Carrillo, Fernando

    2008-01-01

    The evaluation of a preliminary study on the possible implementation of a Mentorship Plan in the Faculty of Teacher Education at the University of Lleida (UdL) is described. A total of sixty-seven first-year Special- and Nursery School-education teacher students participated in this survey. Results were evaluated in both qualitative and…

  18. Preliminary results on ^241,243Am and ^235U (n,γ) cross sections measured at DANCE

    NASA Astrophysics Data System (ADS)

    Jandel, M.; Bredeweg, T. A.; Fowler, M. M.; Bond, E. M.; O'Donnell, J. M.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Macri, R. A.; Wu, C.-Y.; Becker, J. A.

    2006-10-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory (LANL) was used for neutron capture cross sections measurements. Its high granularity of 160 BaF2 detectors allows for highly efficient detection of prompt gamma-rays following a neutron capture. DANCE is located on the 20.26 m neutron flight path 14 at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center (LANSCE). The moderated production target provides neutrons in the 0.02 eV - 500 keV energy range. An analysis of neutron capture measurements on ^241,243Am and ^235U targets will be presented. The experiments were carried out using a customized Parallel-Plate Avalanche Counter (PPAC) detector installed in the center of the DANCE array. The PPAC was used as a fission-tagging detector to separate (n,γ) from (n,fission) events. Preliminary results of (n,γ) cross sections will be presented and compared with the available evaluated data for neutron energies from 0.02 eV to 1 keV. Additional neutron capture measurements with DANCE will be briefly discussed.

  19. The Utility of Pitch Elevation in the Evaluation of Oropharyngeal Dysphagia: Preliminary Findings

    ERIC Educational Resources Information Center

    Malandraki, Georgia A.; Hind, Jacqueline A.; Gangnon, Ronald; Logemann, Jeri A.; Robbins, JoAnne

    2011-01-01

    Purpose: To evaluate the utility of a pitch elevation task in the assessment of oropharyngeal dysphagia. Method: This study was a pilot prospective cohort study including 40 consecutive patients (16 male and 24 female) who were referred by their physician for a swallowing evaluation. Patients were evaluated with a noninstrumental clinical…

  20. Economic Evaluation of Short-Term Wind Power Forecasts in ERCOT: Preliminary Results; Preprint

    SciTech Connect

    Orwig, K.; Hodge, B. M.; Brinkman, G.; Ela, E.; Milligan, M.; Banunarayanan, V.; Nasir, S.; Freedman, J.

    2012-09-01

    Historically, a number of wind energy integration studies have investigated the value of using day-ahead wind power forecasts for grid operational decisions. These studies have shown that there could be large cost savings gained by grid operators implementing the forecasts in their system operations. To date, none of these studies have investigated the value of shorter-term (0 to 6-hour-ahead) wind power forecasts. In 2010, the Department of Energy and National Oceanic and Atmospheric Administration partnered to fund improvements in short-term wind forecasts and to determine the economic value of these improvements to grid operators, hereafter referred to as the Wind Forecasting Improvement Project (WFIP). In this work, we discuss the preliminary results of the economic benefit analysis portion of the WFIP for the Electric Reliability Council of Texas. The improvements seen in the wind forecasts are examined, then the economic results of a production cost model simulation are analyzed.

  1. Preliminary Design, Feasibility and Cost Evaluation of 1- to 15-Kilometer Height Steel Towers

    NASA Technical Reports Server (NTRS)

    Shanker, Ajay

    2003-01-01

    Design and construction of tall towers is an on-going research program of NASA. The agency has already done preliminary review in this area and has determined that multi-kilometer height towers are technically and economically feasible. The proposed towers will provide high altitude launch platforms reaching above eighty percent of Earth's atmosphere and provide tremendous gains in the potential energy as well as substantial reduction in aerodynamic drag. NASA has also determined that a 15-KM tower will have many useful applications in: (i)Meteorology,(ii)Oceanography, (iii)Astronomy, (iv)High Altitude Launch, (v)Physics Drop Tower, (vi) Biosphere Research, (vii) Nanotechnology, (viii) Energy/Power, (ix)Broadband Wireless Technology, (x)Space Transportation and (xi)Space Tourism.

  2. Preliminary In Vivo Evaluation of a Hybrid Armored Vascular Graft Combining Electrospinning and Additive Manufacturing Techniques

    PubMed Central

    Spadaccio, Cristiano; Nappi, Francesco; De Marco, Federico; Sedati, Pietro; Sutherland, Fraser W.H.; Chello, Massimo; Trombetta, Marcella; Rainer, Alberto

    2016-01-01

    In this study, we tested in vivo effectiveness of a previously developed poly-l-lactide/poly-ε-caprolactone armored vascular graft releasing heparin. This bioprosthesis was designed in order to overcome the main drawbacks of tissue-engineered vascular grafts, mainly concerning poor mechanical properties, thrombogenicity, and endothelialization. The bioprosthesis was successfully implanted in an aortic vascular reconstruction model in rabbits. All grafts implanted were patent at four weeks postoperatively and have been adequately populated by endogenous cells without signs of thrombosis or structural failure and with no need of antiplatelet therapy. The results of this preliminary study might warrant for further larger controlled in vivo studies to further confirm these findings. PMID:26949333

  3. A preliminary evaluation of child restraints and anchorage systems for an Australian car.

    PubMed

    Charlton, Judith L; Fildes, Brian; Laemmle, Ronald; Smith, Stuart; Douglas, Fiona

    2004-01-01

    This study examined the performance of three rear-facing and two forward-facing child restraints (CRS) with three anchorage systems: standard seatbelt, LATCH (flexible) and ISOFIX (rigid). Frontal (64 km/h) and side impact (15 km/h) HyGe sled tests were conducted using a sedan buck. Overall, the preliminary findings suggested superior performance of rigid over seatbelt and flexible anchorages, particularly in side impacts. The results also suggest a need for design improvement for CRS with flexible anchorages to increase stability in side impacts. The findings have important implications for the proposed introduction of changes to Australian Standards for CRS to permit both flexible and rigid systems to coexist with conventional seatbelt anchorage systems. PMID:15319118

  4. Preliminary evaluation of environmental issues on the use of peat as an energy source

    SciTech Connect

    King, R.; Richardson, S.; Walters, A.; Boesch, L.; Thomson, W.; Irons, J.

    1980-03-14

    A study to characterize the environmental issues, that would arise from an extensive peat utilization program has been initiated. The objectives of this preliminary report are to: identify the environmental issues and potential problems; examine the significance of issues in the geographical regions where peat use could be developed; and establish a methodology by which issues can be resolved or clarified through future coordinated private, state, and federal programs. An overview of peat development including discussions on conversion technologies, extraction and harvesting procedures, and land reclamation is presented. Environmental concerns are in the areas of water resources and quality, air quality, health and safety issues, solid waste management, and land reclamation. The general environmental issues, resource availability, and attitudes associated with potential peat development in ten states, containing an estimated 90 percent of US peat resources were described. The ten states reviewed are Alaska, Minnesota, Michigan, Maine, North and South Carolina, Wisconsin, New York, Florida, and Louisiana. (DMC)

  5. Pharmacological Evaluation and Preliminary Pharmacokinetics Studies of a New Diclofenac Prodrug without Gastric Ulceration Effect

    PubMed Central

    dos Santos, Jean Leandro; Moreira, Vanessa; Campos, Michel Leandro; Chelucci, Rafael Consolin; Barbieri, Karina Pereira; de Castro Souto, Pollyana Cristina Maggio; Matsubara, Márcio Hideki; Teixeira, Catarina; Bosquesi, Priscila Longhin; Peccinini, Rosângela Gonçalves; Chin, Chung Man

    2012-01-01

    Long-term nonsteroidal anti-inflammatory drugs (NSAIDs) therapy has been associated with several adverse effects such as gastric ulceration and cardiovascular events. Among the molecular modifications strategies, the prodrug approach is a useful tool to discover new safe NSAIDs. The 1-(2,6-dichlorophenyl)indolin-2-one is a diclofenac prodrug which demonstrated relevant anti-inflammatory properties without gastro ulceration effect. In addition, the prodrug decreases PGE2 levels, COX-2 expression and cellular influx into peritoneal cavity induced by carrageenan treatment. Preliminary pharmacokinetic studies have shown in vivo bioconversion of prodrug to diclofenac. This prodrug is a new nonulcerogenic NSAID useful to treat inflammatory events by long-term therapy. PMID:23203127

  6. Histological and ultrastructural evaluation of extracorporeal shock wave lithotripsy-induced acute renal lesions: preliminary report.

    PubMed

    Rigatti, P; Colombo, R; Centemero, A; Francesca, F; Di Girolamo, V; Montorsi, F; Trabucchi, E

    1989-01-01

    Biopsy material taken from kidneys of 14 patients with renal stones before performing extracorporeal shock wave lithotripsy (ESWL) and an average of 15 days after was examined histologically and ultrastructurally. In the post-ESWL specimens, light microscopy revealed edema and extravasation of urine and blood into the interstitial spaces, blocking of cortical tubules by hemorrhagic streaks and widespread dilatation of the veins, with signs of endothelial destruction and partial organization of thrombi. By using the electron microscope, abnormalities of the endothelium and glomerular epithelium, hemosiderin accumulations in the tubular cells and small linear patches of fibrosis at the corticomedullary junction and in the cortical interstitial spaces were seen. This preliminary report indicates that renal damage can be shown soon after ESWL on histological and ultrastructural studies and that the lesions observed can be either reversible or permanent.

  7. Next Generation Munitions Handler: Human-Machine Interface and Preliminary Performance Evaluation

    SciTech Connect

    Draper, J.V.; Jansen, J.F.; Pin, F.G.; Rowe, J.C.

    1999-04-25

    The Next Generation Munitions Handler/Advanced Technology Demonstrator (NGMI-VATTD) is a technology demonstrator for the application of an advanced robotic device for re-arming U.S. Air Force (USAF) and U.S. Navy (USN) tactical fighters. It comprises two key hardware components: a heavy-lift dexterous manipulator (HDM) and a nonholonomic mobility platform. The NGMWATTD is capable of lifting weapons up to 4400 kg (2000 lb) and placing them on any weapons rack on existing fighters (including the F-22 Raptor). This report describes the NGMH mission with particular reference to human-machine interfaces. It also describes preliminary testing to garner feedback about the heavy-lift manipulator arm from experienced fighter load crewmen. The purpose of the testing was to provide preliminary information about control system parameters and to gather feed- back from users about manipulator arm functionality. To that end, the Air Force load crewmen interacted with the NGMWATTD in an informal testing session and provided feedback about the performance of the system. Certain con- trol system parameters were changed during the course of the testing and feedback from the participants was used to make a rough estimate of "good" initial operating parameters. Later, formal testing will concentrate within this range to identify optimal operating parameters. User reactions to the HDM were generally positive, All of the USAF personnel were favorably impressed with the capabilities of the system. Fine-tuning operating parameters created a system even more favorably regarded by the load crews. Further adjustment to control system parameters will result in a system that is operationally efficient, easy to use, and well accepted by users.

  8. Evaluation of vectorized Monte Carlo algorithms on GPUs for a neutron Eigenvalue problem

    SciTech Connect

    Du, X.; Liu, T.; Ji, W.; Xu, X. G.; Brown, F. B.

    2013-07-01

    Conventional Monte Carlo (MC) methods for radiation transport computations are 'history-based', which means that one particle history at a time is tracked. Simulations based on such methods suffer from thread divergence on the graphics processing unit (GPU), which severely affects the performance of GPUs. To circumvent this limitation, event-based vectorized MC algorithms can be utilized. A versatile software test-bed, called ARCHER - Accelerated Radiation-transport Computations in Heterogeneous Environments - was used for this study. ARCHER facilitates the development and testing of a MC code based on the vectorized MC algorithm implemented on GPUs by using NVIDIA's Compute Unified Device Architecture (CUDA). The ARCHER{sub GPU} code was designed to solve a neutron eigenvalue problem and was tested on a NVIDIA Tesla M2090 Fermi card. We found that although the vectorized MC method significantly reduces the occurrence of divergent branching and enhances the warp execution efficiency, the overall simulation speed is ten times slower than the conventional history-based MC method on GPUs. By analyzing detailed GPU profiling information from ARCHER, we discovered that the main reason was the large amount of global memory transactions, causing severe memory access latency. Several possible solutions to alleviate the memory latency issue are discussed. (authors)

  9. Evaluation of water transfer from saturated lightweight aggregate to cement paste matrix by neutron radiography

    NASA Astrophysics Data System (ADS)

    Maruyama, I.; Kanematsu, M.; Noguchi, T.; Iikura, H.; Teramoto, A.; Hayano, H.

    2009-06-01

    In high-strength concrete with low water-cement ratio, self-desiccation occurs due to cement hydration and causes shrinkage and an increased risk of cracking. While high-strength concrete has a denser matrix than normal-strength concrete, resulting in lower permeability, early-age cracks would cancel out this advantage. For the mitigation of this self-desiccation and resultant shrinkage, water-saturated porous aggregate, such as artificial lightweight aggregate, may be used in high-strength concrete. In this contribution, for the purpose of clarification of the volume change of high-strength concrete containing water-saturated lightweight aggregate, water transfer from the lightweight aggregate to cement paste matrix is visualized by neutron radiography. As a result, it is clear that water was supplied to the cement paste matrix in the range 3-8 mm from the surface of the aggregate, and the osmotic forces may yield water transfer around lightweight aggregate in a few hours after mixing.

  10. Evaluation of precision and accuracy of selenium measurements in biological materials using neutron activation analysis

    SciTech Connect

    Greenberg, R.R.

    1988-01-01

    In recent years, the accurate determination of selenium in biological materials has become increasingly important in view of the essential nature of this element for human nutrition and its possible role as a protective agent against cancer. Unfortunately, the accurate determination of selenium in biological materials is often difficult for most analytical techniques for a variety of reasons, including interferences, complicated selenium chemistry due to the presence of this element in multiple oxidation states and in a variety of different organic species, stability and resistance to destruction of some of these organo-selenium species during acid dissolution, volatility of some selenium compounds, and potential for contamination. Neutron activation analysis (NAA) can be one of the best analytical techniques for selenium determinations in biological materials for a number of reasons. Currently, precision at the 1% level (1s) and overall accuracy at the 1 to 2% level (95% confidence interval) can be attained at the U.S. National Bureau of Standards (NBS) for selenium determinations in biological materials when counting statistics are not limiting (using the {sup 75}Se isotope). An example of this level of precision and accuracy is summarized. Achieving this level of accuracy, however, requires strict attention to all sources of systematic error. Precise and accurate results can also be obtained after radiochemical separations.

  11. Configuration evaluation and criteria plan. Volume 2: Evaluation critera plan (preliminary). Space Transportation Main Engine (STME) configuration study

    NASA Technical Reports Server (NTRS)

    Bair, E. K.

    1986-01-01

    The unbiased selection of the Space Transportation Main Engine (STME) configuration requires that the candidate engines be evaluated against a predetermined set of criteria which must be properly weighted to emphasize critical requirements defined prior to the actual evaluation. The evaluation and selection process involves the following functions: (1) determining if a configuration can satisfy basic STME requirements (yes/no); (2) defining the evaluation criteria; (3) selecting the criteria relative importance or weighting; (4) determining the weighting sensitivities; and (5) establishing a baseline for engine evaluation. The criteria weighting and sensitivities are cost related and are based on mission models and vehicle requirements. The evaluation process is used as a coarse screen to determine the candidate engines for the parametric studies and as a fine screen to determine concept(s) for conceptual design. The criteria used for the coarse and fine screen evaluation process is shown. The coarse screen process involves verifying that the candidate engines can meet the yes/no screening requirements and a semi-subjective quantitative evaluation. The fine screen engines have to meet all of the yes/no screening gates and are then subjected to a detailed evaluation or assessment using the quantitative cost evaluation processes. The option exists for re-cycling a concept through the quantitative portion of the screening and allows for some degree of optimization. The basic vehicle is a two stage LOX/HC, LOX/LH2 parallel burn vehicle capable of placing 150,000 lbs in low Earth orbit (LEO).

  12. Evaluation of the sensitivity of the gas-discharge gamma-counters to the concomitant neutron radiation

    NASA Astrophysics Data System (ADS)

    Pikalov, G. L.; Kiseev, S. V.

    2015-11-01

    In the fields of gamma-neutron radiation the accuracy measurement of gamma- ray doses depends on their sensitivity to concomitant neutron radiation. In this connection, verification results of gamma-dosimetry on the installation with isotope cobalt or cesium sources are not always adequate to measurement results in real gamma-neutron fields. The data prove, that the sensitivity coefficients of gas-discharge gamma-dosimeters at PRIZ-M reactor is 1.23 larger as compared to Co60 source, due to the effect of the concomitant neutrons on their indications. The error due to the neutrons effect can be significantly reduced or eliminated completely, if gamma-dosimeters calibrated in the field of gamma-neutron radiation, adequate spectral and dose characteristics to radiation fields in which they are used.

  13. Preliminary evaluation of a virtual reality dental simulation system on drilling operation.

    PubMed

    Wang, Dangxiao; Zhao, Siming; Li, Teng; Zhang, Yuru; Wang, Xiaoyan

    2015-01-01

    To evaluate the fidelity of the iDental system and investigate its utility and performance on simulated drilling operations, user studies consisting of objective and subjective evaluations were performed. A voxel-based drilling simulation sub-system in the iDental system was employed for evaluation. Twenty participants were enrolled to take part in the experiments and were divided into two groups: novice and resident. A combined evaluation method including objective and subjective methods was employed. The objective evaluation included two dental drilling tasks: caries removal operation and pulp chamber opening operation. In the subjective method, participants were required to complete a questionnaire to evaluate the fidelity of the system after the operation task. Based on the structured global assessment scales in the questionnaire, the average subjective evaluation scores of the proposed metrics were greater than 4.5, demonstrating that the system operated above medium fidelity. Dentists expressed great interest and positive attitudes toward the potential of the iDental system. The objective evaluation data including time spent and the volume of removed healthy and carious tissue were obtained. Although no significant differences could be found between the two groups, the volume of removed caries and the depth of pulp chamber insertion manifested small standard deviations. Evaluation results illustrated that dentists were willing to use the virtual reality training system. Several future research topics were identified, including increasing the task difficulty, improving the system fidelity and introducing appropriate finger rest points.

  14. Evaluation of Aluminum-Boron Carbide Neutron Absorbing Materials for Interim Storage of Used Nuclear Fuel

    SciTech Connect

    Wang, Lumin; Wierschke, Jonathan Brett

    2015-04-08

    The objective of this work was to understand the corrosion behavior of Boral® and Bortec® neutron absorbers over long-term deployment in a used nuclear fuel dry cask storage environment. Corrosion effects were accelerated by flowing humidified argon through an autoclave at temperatures up to 570°C. Test results show little corrosion of the aluminum matrix but that boron is leaching out of the samples. Initial tests performed at 400 and 570°C were hampered by reduced flow caused by the rapid build-up of solid deposits in the outlet lines. Analysis of the deposits by XRD shows that the deposits are comprised of boron trioxide and sassolite (H3BO3). The collection of boron- containing compounds in the outlet lines indicated that boron was being released from the samples. Observation of the exposed samples using SEM and optical microscopy show the growth of new phases in the samples. These phases were most prominent in Bortec® samples exposed at 570°C. Samples of Boral® exposed at 570°C showed minimal new phase formation but showed nearly the complete loss of boron carbide particles. Boron carbide loss was also significant in Boral samples at 400°C. However, at 400°C phases similar to those found in Bortec® were observed. The rapid loss of the boron carbide particles in the Boral® is suspected to inhibit the formation of the new secondary phases. However, Material samples in an actual dry cask environment would be exposed to temperatures closer to 300°C and less water than the lowest test. The results from this study conclude that at the temperature and humidity levels present in a dry cask environment, corrosion and boron leaching will have no effect on the performance of Boral® and Bortec® to maintain criticality control.

  15. Extraction, preliminary characterization and evaluation of in vitro antitumor and antioxidant activities of polysaccharides from Mentha piperita.

    PubMed

    Liu, Xin; Sun, Zhen-Liang; Jia, Ai-Rong; Shi, Ya-Ping; Li, Rui-Hong; Yang, Pei-Ming

    2014-09-15

    This study describes the extraction, preliminary characterization and evaluation of the in vitro antitumor and antioxidant activities of polysaccharides extracted from Mentha piperita (MPP). The optimal parameters for the extraction of MPP were obtained by Box-Behnken experimental design and response surface methodology (RSM) at the ratio of water to raw material of 20, extraction time of 1.5 h and extraction temperature at 80 °C. Chemical composition analysis showed that MPP was mainly composed of glucuronic acid, galacturonic acid, glucose, galactose and arabinose, and the molecular weight of its two major fractions were estimated to be about 2.843 and 1.139 kDa, respectively. In vitro bioactivity experiments showed that MPP not only inhibited the growth of A549 cells but possessed potent inhibitory action against DNA topoisomerase I (topo I), and an appreciative antioxidant action as well. These results indicate that MPP may be useful for developing safe natural health products.

  16. Site selection and preliminary evaluation of potential solar-industrial-process-heat applications for federal buildings in Texas

    SciTech Connect

    Branz, M A

    1980-09-30

    The potential for solr process heat applications for federal buildings in Texas is assessed. The three sites considered are Reese Air Force Base, Lubbock; Fort Bliss, El Paso; and Dyess Air Force Base, Abilene. The application at Lubbock is an electroplating and descaling facility for aircraft maintenance. The one at El Paso is a laundry facility. The Abilene system would use solar heat to preheat boiler feedwater makeup for the base hospital boiler plant. The Lubbock site is found to be the most appropriate one for a demonstration plant, with the Abilene site as an alternate. The processes at each site are described. A preliminary evaluation of the potential contribution by solar energy to the electroplating facility at Reese AFB is included. (LEW)

  17. Extraction, Preliminary Characterization and Evaluation of in Vitro Antitumor and Antioxidant Activities of Polysaccharides from Mentha piperita

    PubMed Central

    Liu, Xin; Sun, Zhen-Liang; Jia, Ai-Rong; Shi, Ya-Ping; Li, Rui-Hong; Yang, Pei-Ming

    2014-01-01

    This study describes the extraction, preliminary characterization and evaluation of the in vitro antitumor and antioxidant activities of polysaccharides extracted from Mentha piperita (MPP). The optimal parameters for the extraction of MPP were obtained by Box-Behnken experimental design and response surface methodology (RSM) at the ratio of water to raw material of 20, extraction time of 1.5 h and extraction temperature at 80 °C. Chemical composition analysis showed that MPP was mainly composed of glucuronic acid, galacturonic acid, glucose, galactose and arabinose, and the molecular weight of its two major fractions were estimated to be about 2.843 and 1.139 kDa, respectively. In vitro bioactivity experiments showed that MPP not only inhibited the growth of A549 cells but possessed potent inhibitory action against DNA topoisomerase I (topo I), and an appreciative antioxidant action as well. These results indicate that MPP may be useful for developing safe natural health products. PMID:25226538

  18. Multivariate Evaluation of Student Selection Strategies in Open and Traditional Education. A Preliminary Report.

    ERIC Educational Resources Information Center

    Dornseif, Allan W.; And Others

    This study is part of a continuing program of evaluation of open vs. traditional education at the junior high school level. Incoming seventh graders were assigned to open and control groups to evaluate relative effects on academic underachievement, socialization, and general academic "success" as a function of various means of student selection.…

  19. Assessing QuADEM: Preliminary Notes on a New Method for Evaluating Online Language Learning Courseware

    ERIC Educational Resources Information Center

    Strobl, Carola; Jacobs, Geert

    2011-01-01

    In this article, we set out to assess QuADEM (Quality Assessment of Digital Educational Material), one of the latest methods for evaluating online language learning courseware. What is special about QuADEM is that the evaluation is based on observing the actual usage of the online courseware and that, from a checklist of 12 different components,…

  20. Evaluation of equivalent dose from neutrons and activation products from a 15-MV X-ray LINAC.

    PubMed

    Israngkul-Na-Ayuthaya, Isra; Suriyapee, Sivalee; Pengvanich, Phongpheath

    2015-11-01

    A high-energy photon beam that is more than 10 MV can produce neutron contamination. Neutrons are generated by the [γ,n] reactions with a high-Z target material. The equivalent neutron dose and gamma dose from activation products have been estimated in a LINAC equipped with a 15-MV photon beam. A Monte Carlo simulation code was employed for neutron and photon dosimetry due to mixed beam. The neutron dose was also experimentally measured using the Optically Stimulated Luminescence (OSL) under various conditions to compare with the simulation. The activation products were measured by gamma spectrometer system. The average neutron energy was calculated to be 0.25 MeV. The equivalent neutron dose at the isocenter obtained from OSL measurement and MC calculation was 5.39 and 3.44 mSv/Gy, respectively. A gamma dose rate of 4.14 µSv/h was observed as a result of activations by neutron inside the treatment machine. The gamma spectrum analysis showed (28)Al, (24)Na, (54)Mn and (60)Co. The results confirm that neutrons and gamma rays are generated, and gamma rays remain inside the treatment room after the termination of X-ray irradiation. The source of neutrons is the product of the [γ,n] reactions in the machine head, whereas gamma rays are produced from the [n,γ] reactions (i.e. neutron activation) with materials inside the treatment room. The most activated nuclide is (28)Al, which has a half life of 2.245 min. In practice, it is recommended that staff should wait for a few minutes (several (28)Al half-lives) before entering the treatment room after the treatment finishes to minimize the dose received.

  1. Evaluation of equivalent dose from neutrons and activation products from a 15-MV X-ray LINAC.

    PubMed

    Israngkul-Na-Ayuthaya, Isra; Suriyapee, Sivalee; Pengvanich, Phongpheath

    2015-11-01

    A high-energy photon beam that is more than 10 MV can produce neutron contamination. Neutrons are generated by the [γ,n] reactions with a high-Z target material. The equivalent neutron dose and gamma dose from activation products have been estimated in a LINAC equipped with a 15-MV photon beam. A Monte Carlo simulation code was employed for neutron and photon dosimetry due to mixed beam. The neutron dose was also experimentally measured using the Optically Stimulated Luminescence (OSL) under various conditions to compare with the simulation. The activation products were measured by gamma spectrometer system. The average neutron energy was calculated to be 0.25 MeV. The equivalent neutron dose at the isocenter obtained from OSL measurement and MC calculation was 5.39 and 3.44 mSv/Gy, respectively. A gamma dose rate of 4.14 µSv/h was observed as a result of activations by neutron inside the treatment machine. The gamma spectrum analysis showed (28)Al, (24)Na, (54)Mn and (60)Co. The results confirm that neutrons and gamma rays are generated, and gamma rays remain inside the treatment room after the termination of X-ray irradiation. The source of neutrons is the product of the [γ,n] reactions in the machine head, whereas gamma rays are produced from the [n,γ] reactions (i.e. neutron activation) with materials inside the treatment room. The most activated nuclide is (28)Al, which has a half life of 2.245 min. In practice, it is recommended that staff should wait for a few minutes (several (28)Al half-lives) before entering the treatment room after the treatment finishes to minimize the dose received. PMID:26265661

  2. Evaluation of equivalent dose from neutrons and activation products from a 15-MV X-ray LINAC

    PubMed Central

    Israngkul-Na-Ayuthaya, Isra; Suriyapee, Sivalee; Pengvanich, Phongpheath

    2015-01-01

    A high-energy photon beam that is more than 10 MV can produce neutron contamination. Neutrons are generated by the [γ,n] reactions with a high-Z target material. The equivalent neutron dose and gamma dose from activation products have been estimated in a LINAC equipped with a 15-MV photon beam. A Monte Carlo simulation code was employed for neutron and photon dosimetry due to mixed beam. The neutron dose was also experimentally measured using the Optically Stimulated Luminescence (OSL) under various conditions to compare with the simulation. The activation products were measured by gamma spectrometer system. The average neutron energy was calculated to be 0.25 MeV. The equivalent neutron dose at the isocenter obtained from OSL measurement and MC calculation was 5.39 and 3.44 mSv/Gy, respectively. A gamma dose rate of 4.14 µSv/h was observed as a result of activations by neutron inside the treatment machine. The gamma spectrum analysis showed 28Al, 24Na, 54Mn and 60Co. The results confirm that neutrons and gamma rays are generated, and gamma rays remain inside the treatment room after the termination of X-ray irradiation. The source of neutrons is the product of the [γ,n] reactions in the machine head, whereas gamma rays are produced from the [n,γ] reactions (i.e. neutron activation) with materials inside the treatment room. The most activated nuclide is 28Al, which has a half life of 2.245 min. In practice, it is recommended that staff should wait for a few minutes (several 28Al half-lives) before entering the treatment room after the treatment finishes to minimize the dose received. PMID:26265661

  3. Large climate-moderating envelopes for enclosed structures: a preliminary evaluation of energy conservation potential

    SciTech Connect

    Wendt, R.L.; Giles, G.E.; Park, J.E.

    1981-12-01

    An investigation was made of the basic impacts of putting a large secondary enclosure around a number of functions and thereby creating a Large Climate Moderating Envelope (LCME). This study is a preliminary estimate of the energy conservation benefits of an LCME. A hypothetical LMCE design was chosen and a coupled fluid dynamic and energy transport analysis was performed to estimate the energy conservation potential of this design. The heat transfer models included insolation, outside air temperature and wind, thermal radiation exchange with the sky, and between the fabric and ground and thermal storage in the earth mass beneath the LCME. The energy transported within the fluid by the buoyancy driven circulation was modeled as an incompressible fluid utilizing the Boussinesq approximation. The climatic conditions were assumed to vary in smooth repeating daily cycles. The numerical simulation of climatic variation was continued until the results within the LCME achieved a repeating daily cycle. The results for selected seasonally characteristic days were utilized to estimate the annual energy consumption of structures within an LCME relative to similar structures exposed to the exterior environment. The relative annual energy savings for summer-dominated climates was estimated to be approx. 70%. The energy savings for a winter-dominated climate LCME were estimated to be somewhat smaller but the LCME concept could offer significant benefits for agricultural applications for this type of climate.

  4. Preliminary evaluation of thematic mapper sensor characteristics relative to land cover/land use discrimination

    NASA Technical Reports Server (NTRS)

    Williams, D. L.; Irons, J. R.; Markham, B. L.; Nelson, R. F.; Toll, D. L.; Latty, R. S.; Stauffer, M. L.

    1983-01-01

    Preliminary experimental results of airborne thematic mapper (TM) data taken to quantify the effect of three major TM sensor parameters, spectral, spatial, and radiometric resolution, six months after launch of Landsat-4 are reported. The flight took place on Nov. 2, 1982 over Washington, D.C., and data gathered were compared with ground reference data from color airborne photography on a 1:40,000 scale. Analyses proceeded by deleting one band from each of four data sets, thus making the data equivalent to MSS data. Attention was directed to land cover/use classes in a quick-look format. A per-pixel maximum likelihood scheme was found to increase the recognition and dicrimination categorization capabilities. Finer spatial resolution, however, impeded classification due to increased within-class variability of the field-center pixels, which also incresed class overlap in the spectral data base. Improved data analyses techniques are therefore needed to exploit the available higher spatial resolution of the TM.

  5. Preliminary evaluation of ground-water flow in Bear Creek Valley, the Oak Ridge Reservation, Tennessee

    USGS Publications Warehouse

    Bailey, Z.C.

    1988-01-01

    Bear Creek Valley, Tennessee contains hazardous waste disposal sites where contaminants leach into ground and surface water. Groundwater flow and the potential migration of contaminants is poorly understood. The Valley is underlain by calcareous shale that contains limestone units. Ridges to the north and south are underlain by interbedded sandstones, siltstone and shale, and by massive, siliceous dolomite, respectively. The bedrock, which dips about 45 degrees southeast, is overlain by regolith to a maximum thickness of 80 ft. Observed hydraulic conductivities for the regolith range from 0.01 to 13 ft/day, and for the bedrock, from 0.001 to 11 ft/day. Groundwater flow is probably toward streams and is preferential along strike because of an areal anisotropy in hydraulic conductivity. A cross sectional groundwater flow model was used to test the conceptualized flow system and to help identify areas where additional data are needed. The preliminary model shows a pattern of recharge at both ridges, flow toward the valley, and upward flow that discharges into Bear Creek. Final model values of hydraulic conductivity in the bedrock range from 0.01 to 0.1 ft/day and reflect an areal anisotropy ratio of 1:5. Simulated recharge was 10 inches/year. (USGS)

  6. Development and Preliminary Evaluation of a 1-Week Summer Treatment Program for Separation Anxiety Disorder

    PubMed Central

    Santucci, Lauren C.; Ehrenreich, Jill T.; Trosper, Sarah E.; Bennett, Shannon M.; Pincus, Donna B.

    2011-01-01

    Numerous clinical trials have demonstrated the efficacy of cognitive behavior therapy (CBT) for the treatment of childhood Separation Anxiety Disorder (SAD) and other anxiety disorders (Velting, Setzer, & Albano, 2004), yet additional research may still be needed to better access and engage anxious youth (Kendall, Suveg, & Kingery, 2006). In this study, we investigated the acceptability and preliminary utility of a group cognitive-behavioral intervention for school-aged girls with SAD provided within an intensive, 1-week setting. The development of the proposed treatment strategy, a 1-week summer treatment program, was predicated on evidence supporting the need for childhood treatments that are developmentally sensitive, allow for creative application of intervention components, incorporate a child’s social context, and ultimately establish new pathways for dissemination to the community. The summer treatment program for SAD was pilot-tested using a case-series design with 5 female children, aged 8 to 11, each with a principal diagnosis of SAD. For 4 of the 5 participants, treatment gains were evidenced by changes in diagnostic status, significant reductions in measures of avoidance, and improvements on self- and parent-report measures of anxiety symptomology. Specifically, severity of SAD symptoms decreased substantially at posttreatment for each participant and, 2 months following treatment, none of the participants met diagnostic criteria for the disorder. A fifth participant experienced substantive improvement in diagnostic status prior to the onset of treatment and, though she evidenced continued improvements following treatment, the role of the intervention in such improvements is less clear. PMID:21935300

  7. Biogeographic perspective of speciation among desert tortoises in the genus Gopherus: a preliminary evaluation

    USGS Publications Warehouse

    Edwards, Taylor; Vaughn, Mercy; Meléndez Torres, Cristina; Karl, Alice E.; Rosen, Philip C.; Berry, Kristin H.; Murph, Robert W.

    2013-01-01

    The enduring processes of time, climate, and adaptation have sculpted the distribution of organisms we observe in the Sonoran Desert. One such organism is Morafka’s desert tortoise, Gopherus morafkai. We apply a genomic approach to identify the evolutionary processes driving diversity in this species and present preliminary findings and emerging hypotheses. The Sonoran Desert form of the tortoise exhibits a continuum of genetic similarity spanning 850 km of Sonoran desertscrub extending from Empalme, Sonora, to Kingman, Arizona. However, at the ecotone between desertscrub and foothills thornscrub we identify a distinct, Sinaloan lineage and this occurrence suggests a more complex evolutionary history for G. morafkai. By using multiple loci from throughout the tortoise’s genome, we aim to determine if divergence between these lineages occurred in allopatry, and further to investigate for signatures of past or current genetic introgression. This international, collaborative project will assist state and federal agencies in developing management strategies that best preserve the evolutionary potential of Morafka’s desert tortoise. Ultimately, an understanding of the evolutionary history of desert tortoises will not only clarify the forces that have driven the divergence in this group, but also contribute to our knowledge of the biogeographic history of the Southwestern deserts and how diversity is maintained within them.

  8. A preliminary evaluation of the relationship between bioconcentration and hydrophobicity for surfactants

    SciTech Connect

    Tolls, J.; Sijm, D.T.H.M.

    1995-10-01

    A statistical analysis was done of the relationship between hydrophobicity and bioconcentration parameters (uptake and elimination rate constants and bioconcentration factor) predicted by the diffusive mass-transfer (DMT) concept of bioconcentration developed previously. The authors employed polychlorinated biphenyls and benzenes (PCB/zs) as model compounds and the octanol/water partition coefficient as hydrophobicity parameter. They conclude that the model is consistent with the data. Subsequently, they applied the DMT concept to a set of preliminary bioconcentration data for surfactants using the critical micelle concentration (CMC) as hydrophobicity parameter. The obtained relationships qualitatively agree with the DMT concept, indicating that hydrophobicity is of great influence on surfactant bioconcentration. Finally, they investigated the hydrophobicity-bioconcentration relationships of surfactants and PCB/zs using aqueous solubility as common hydrophobicity parameter and found the relationships between the bioconcentration parameters and hydrophobicity to agree with the DMT concept. These findings are based on total radiolabel data. Therefore, they need to be confirmed using compound-specific surfactant bioconcentration data.

  9. Preliminary evaluation of an experimental clinical chemistry analyzer developed for space medicine.

    PubMed

    Wu, A H; Gornet, T G; Schenkel, O; Smith-Cronin, L; Graham, G A; Tonnesen, A S; McKinley, B A

    1993-01-01

    An experimental clinical chemistry analyzer system was designed and built to demonstrate the feasibility of clinical chemistry as part of a medical-care system at NASA's planned space station Freedom. We report the performance of the experimental analyzer, called a medical development unit (MDU), for selected analytes in a laboratory setting in preparation for a preliminary clinical trial at patients' bedsides in an intensive-care unit. Within-run CVs ranged from 0.7% for sodium to 7.1% for phosphorus; day-to-day CVs ranged from 1.0% for chloride to 23.4% for calcium. Correlation of patients' blood sample analyses compared well with those by Ektachem E700 and other high-volume central laboratory analyzers (r ranged from 0.933 for creatine kinase MB isoenzyme to 0.997 for potassium), except for hemoglobin (r = 0.901) and calcium (r = 0.823). Although several CVs obtained in this study exceeded theoretical desired precision limits based on biological variations, performance was adequate for clinical laboratory diagnosis. We examined the effect of potentially interfering concentrations of hemoglobin, bilirubin, and lipids: the only effect was negative interference with calcium analyses by high concentrations of bilirubin. We also examined the effects of preanalytical variables and the performance of experimental sample-transfer cups designed to retain sample and reference liquid in microgravity. Continued development of the MDU system is recommended, especially automation of sample processing.

  10. Preliminary Mission Results and Project Evaluation of the Delfi-C3 Nano-satellite

    NASA Astrophysics Data System (ADS)

    Bouwmeester, J.; Aalbers, G. T.; Ubbels, W. J.

    2008-08-01

    This paper discusses preliminary mission results of Delfi-C3 up till the early operations phase. The first section will discuss the design philosophy of Delfi-C3. To reduce operational risks, Delfi-C3 followed the KISS principle and is designed to be Single-Point-of-Failure- free. A balance is made between adoption of professional space engineering customs and standards on one hand and the limitations of small satellites, financial budgets and limited human resources on the other hand. The second section of the paper discusses the project planning and management of Delfi-C3. Addressed are reasonable timelines for the development of a nano-satellite, how to deal with a launch slip and the occasional conflicts between the interest of the students and the interest of the project. The third section of the paper will present the results of the early operations of Delfi-C3. Discussed are the performance of the payloads, the bus and the ground network of the satellite. Finally, an early statement of the mission success will be given.

  11. Preliminary clinical evaluation of a protein chip for tumor marker serodiagnosis of various cancers.

    PubMed

    Balachandra, Kruavon; Laisupasin, Pikul; Dhepakson, Panadda; Warachit, Jiranan; Jantraraksri, Udom; Issaragrisil, Surapol; Yang, Xiao-Li; Hus, Geng-Xi

    2003-09-01

    This preliminary study aimed to investigate sensitivity and specificity of a protein chip system for multi-tumor marker serodiagnosis of ten types of cancers, and to understand the possible clinical applications of this protein chip for the Thai population. The specific cancers diagnosed by this protein chip are lung, breast, liver, cervix, colo-rectal, stomach, ovary, esophagus, prostate and pancreas cancers. We analyzed 215 serum samples of which 165 were obtained from clinically confirmed cancer patients and 50 from healthy people with no evidence of cancer. The sensitivity and specificity of the protein chip were 82.4% and 94.0%, respectively. The success rate of the protein chip for detecting all 10 types of cancers varied from 57% to 100%. The value of the simultaneous measurement of multiple tumor markers using the protein chip for cancer screening lied in the higher sensitivity compared to using single tumor markers for each type of cancer. In short, protein chips may be useful in mass screening for cancer during health checkups as well as for metastasis follow-up of cancer patients.

  12. Neutron facility for radiobiological studies

    NASA Astrophysics Data System (ADS)

    Policroniades, Rafael; Varela, A.; Guzman, J.; Graaf, U.

    1997-02-01

    A neutron facility suitable for radiobiological applications is described. The small chamber can house, either, solid targets or a gas target. Using this facility, absorbed doses ranging up to 7.2 Gy were delivered to Drosophila melanogaster larvae in order to study induced somatic mutation and mitiotic recombination. Some preliminary results concerning these effects, related to a mean neutron energy of 2.15 MeV provided by a d + Be source, are presented.

  13. Compilation and evaluation of 14-MeV neutron-activation cross sections for nuclear technology applications. Set I

    SciTech Connect

    Evain, B.P.; Smith, D.L.; Lucchese, P.

    1985-04-01

    Available 14-MeV experimental neutron activation cross sections are compiled and evaluated for the following reactions of interest for nuclear-energy technology applications: /sup 27/Al(n,p)/sup 27/Mg, Si(n,X)/sup 28/Al, Ti(n,X)/sup 46/Sc, Ti(n,X)/sup 47/Sc, Ti(n,X)/sup 48/Sc, /sup 51/V(n,p)/sup 51/Ti, /sup 51/V(n,..cap alpha..)/sup 48/Sc, Cr(n,X)/sup 52/V, /sup 55/Mn(n,..cap alpha..)/sup 52/V, /sup 55/Mn(n,2n)/sup 54/Mn, Fe(n,X)/sup 54/Mn, /sup 54/Fe(n,..cap alpha..)/sup 51/Cr, /sup 59/Co(n,p)/sup 59/Fe, /sup 59/Co(n,..cap alpha..)/sup 56/Mn, /sup 59/Co(n,2n)/sup 58/Co, /sup 65/Cu(n,p)/sup 65/Ni, Zn(n,X)/sup 64/Cu, /sup 64/Zn(n,2n)/sup 63/Zn, /sup 113/In(n,n')/sup 113m/In, /sup 115/In(n,n') /sup 115m/In. The compiled values are listed and plotted for reference without adjustments. From these collected results those values for which adequate supplementary information on nuclear constants, standards and experimental errors is provided are selected for use in reaction-by-reaction evaluations. These data are adjusted as needed to account for recent revisions in the nuclear constants and cross section standards. The adjusted results are subsequently transformed to equivalent cross sections at 14.7 MeV for the evaluation process. The evaluations are performed utilizing a least-squares method which considers correlations between the experimental data. 440 refs., 41 figs., 46 tabs.

  14. A neutron diffraction and magnetic Barkhausen noise evaluation of defect-induced stress concentrations

    NASA Astrophysics Data System (ADS)

    Sabet-Sharghi, Riaz

    This thesis studies the effect of altering both the drilling technique (mechanical drilling vs. Electro-Chemical Milling) and the sequence of defect introduction and load application on the defect-induced stress distributions in sections of line pipe steel material. The defect-induced stress concentrations in loaded samples with defects introduced whilst loaded (in-situ) and prior to the application of load (pre-drilled) were examined using both neutron diffraction and Magnetic Barkhausen Noise (MBN). These results indicated the presence of potentially large levels of residual stress particularly in the in-situ sample. This is believed to be a result of plastic deformation being introduced by the mechanical drilling process. Similar studies on ECM defects showed no signs of drilling-induced stresses. Experimental stress distribution results from the in-situ and pre-drilled samples were compared to those predicted using a three-dimensional finite element model solution. The overall level of agreement was found to be best for the pre-drilled sample case. The study also aimed to determine the effectiveness of MBN as a non-destructive method for characterizing line pipe samples. Results of an initial experiment are presented showing the effectiveness of MBN for performing quantitative strain analysis on samples. This was determined by comparing MBN-measured stress concentrations with those predicted by theory and reported in the literature. Magnetic Flux Leakage (MFL) tests were also performed on the samples in order to examine any stress-induced differences in MFL response. It was found that the differences in stress distribution between the in-situ and pre-drilled samples were also reflected in the trend of the MFL signal amplitude and shape as a function of applied stress. The original work in this thesis includes the first definitive test of the effects of the order of load application and defect introduction on the resulting stress distributions around through

  15. Mallotojaponins B and C: Total Synthesis, Antiparasitic Evaluation, and Preliminary SAR Studies.

    PubMed

    Grayfer, Tatyana D; Grellier, Philippe; Mouray, Elisabeth; Dodd, Robert H; Dubois, Joëlle; Cariou, Kevin

    2016-02-19

    The first total syntheses of mallotojaponin B and C as well as several analogues have been achieved. Biological evaluation of the synthesized compounds against Plasmodium falciparum and Trypanosoma brucei have also been carried out. PMID:26828239

  16. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect

    Chandler, K.; Eudy, L.

    2007-03-01

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  17. Development and preliminary evaluation of a behavioural HIV prevention program for teenage girls of Latino descent in the USA

    PubMed Central

    Davidson, Tatiana M.; Lopez, Cristina M.; Saulson, Raelle; Borkman, April L.; Soltis, Kathryn; Ruggiero, Kenneth J.; de Arellano, Michael; Wingood, Gina M.; DiClemente, Ralph J.; Danielson, Carla Kmett

    2014-01-01

    National data suggests that teenage girls of Latino descent in the USA are disproportionately affected by HIV with the rate of new infections being approximately 4 times higher compared to White women of comparable age (Centers for Disease Control and Prevention 2013). This paper highlights the need for an effective single-sex HIV prevention program for teenage girls of Latino descent and describes the development and preliminary evaluation of Chicas Healing, Informing, Living and Empowering (CHILE), a culturally-tailored, HIV prevention programme exclusively for teenage girls of Latino descent that was adapted from Sisters Informing, Healing, Living, and Empowering (SiHLE), an evidence-based HIV prevention program that is culturally tailored for African American young women. Theatre testing, a pre-testing methodology to assess consumer response to a demonstration of a product, was utilised to evaluate the relevance and utility of the HIV program as well as opportunities for the integration of cultural constructs. Future directions for the evaluation of CHILE are discussed. PMID:24697607

  18. Preliminary evaluation of effects of best management practices in the Black Earth Creek, Wisconsin, priority watershed

    USGS Publications Warehouse

    Walker, J.F.; Graczyk, D.J.; Olem, H.

    1993-01-01

    Nonpoint-source contamination accounts for a substantial part of the water quality problems in many watersheds. The Wisconsin Nonpoint Source Water Pollution Abatement Program provides matching money for voluntary implementation of various best management practices (BMPs). The effectiveness of BMPs on a drainage-basin scale has not been adequately assessed in Wisconsin by use of data collected before and after BMP implementation. The U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, monitored water quality in the Black Earth Creek watershed in southern Wisconsin from October 1984 through September 1986 (pre-BMP conditions). BMP implementation began during the summer of 1989 and is planned to continue through 1993. Data collection resumed in fall 1989 and is intended to provide information during the transitional period of BMP implementation (1990-93) and 2 years of post-BMP conditions (1994-95). Preliminary results presented for two subbasins in toe Black Earth Creek watershed (Brewery and Garfoot Creeks) are based on data collected during pre-BMP conditions and the first 3 years of the transitional period. The analysis includes the use of regressions to control for natural variability in the data and, hence, enhance the ability to detect changes. Data collected to date (1992) indicate statistically significant differences in storm mass transport of suspended sediment and ammonia nitrogen at Brewery Creek. The central tendency of the regression residuals has decreased with the implementation of BMPs; hence, the improvement in water quality in the Brewery Creek watershed is likely a result of BMP implementation. Differences in storm mass transport at Garfoot Creek were not detected, primarily because of an insufficient number of storms in the transitional period. As practice implementation continues, the additional data will be used to determine the level of management which results in significant improvements in water

  19. Sewage sludge drying by energy recovery from OFMSW composting: Preliminary feasibility evaluation

    SciTech Connect

    Rada, Elena Cristina; Ragazzi, Marco; Villotti, Stefano; Torretta, Vincenzo

    2014-05-01

    Highlights: • The aim is to support the drying of sewage sludge, using a solar greenhouse. • The system allows the exploitation of heat available from OFMSW aerobic process. • Another aim is to face the problem of OFMSW treatment, in particular food waste. • Energy and mass balances are presented for a case study. - Abstract: In this paper an original energy recovery method from composting is analyzed. The integrated system exploits the heat available from the aerobic biochemical process in order to support the drying of sewage sludge, using a specific solar greenhouse. The aim is to tackle the problem of organic waste treatment, with specific regard to food waste. This is done by optimizing the energy consumption of the aerobic process of composting, using the heat produced to solve a second important waste management problem such as the sewage waste treatment. Energy and mass balances are presented in a preliminary feasibility study. Referring to a composting plant with a capacity of 15,000 t/y of food waste, the estimation of the power from recovered heat for the entire plant resulted about 42 kW. The results demonstrated that the energy recoverable can cover part of the heat necessary for the treatment of sludge generated by the population served by the composting plant (in terms of food waste and green waste collection). The addition of a renewable source such as solar energy could cover the residual energy demand. The approach is presented in detail in order for it to be replicated in other case studies or at full scale applications.

  20. A Preliminary Evaluation of Supersonic Transport Category Vehicle Operations in the National Airspace System

    NASA Technical Reports Server (NTRS)

    Underwood, Matthew C.; Guminsky, Michael D.

    2015-01-01

    Several public sector businesses and government agencies, including the National Aeronautics and Space Administration are currently working on solving key technological barriers that must be overcome in order to realize the vision of low-boom supersonic flights conducted over land. However, once these challenges are met, the manner in which this class of aircraft is integrated in the National Airspace System may become a potential constraint due to the significant environmental, efficiency, and economic repercussions that their integration may cause. Background research was performed on historic supersonic operations in the National Airspace System, including both flight deck procedures and air traffic controller procedures. Using this information, an experiment was created to test some of these historic procedures in a current-day, emerging Next Generation Air Transportation System (NextGen) environment and observe the interactions between commercial supersonic transport aircraft and modern-day air traffic. Data was gathered through batch simulations of supersonic commercial transport category aircraft operating in present-day traffic scenarios as a base-lining study to identify the magnitude of the integration problems and begin the exploration of new air traffic management technologies and architectures which will be needed to seamlessly integrate subsonic and supersonic transport aircraft operations. The data gathered include information about encounters between subsonic and supersonic aircraft that may occur when supersonic commercial transport aircraft are integrated into the National Airspace System, as well as flight time data. This initial investigation is being used to inform the creation and refinement of a preliminary Concept of Operations and for the subsequent development of technologies that will enable overland supersonic flight.

  1. Evaluation of Passive Multilayer Cloud Detection Using Preliminary CloudSat and CALIPSO Cloud Profiles

    NASA Astrophysics Data System (ADS)

    Minnis, P.; Sun-Mack, S.; Chang, F.; Huang, J.; Nguyen, L.; Ayers, J. K.; Spangenberg, D. A.; Yi, Y.; Trepte, C. R.

    2006-12-01

    During the last few years, several algorithms have been developed to detect and retrieve multilayered clouds using passive satellite data. Assessing these techniques has been difficult due to the need for active sensors such as cloud radars and lidars that can "see" through different layers of clouds. Such sensors have been available only at a few surface sites and on aircraft during field programs. With the launch of the CALIPSO and CloudSat satellites on April 28, 2006, it is now possible to observe multilayered systems all over the globe using collocated cloud radar and lidar data. As part of the A- Train, these new active sensors are also matched in time ad space with passive measurements from the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Microwave Scanning Radiometer - EOS (AMSR-E). The Clouds and the Earth's Radiant Energy System (CERES) has been developing and testing algorithms to detect ice-over-water overlapping cloud systems and to retrieve the cloud liquid path (LWP) and ice water path (IWP) for those systems. One technique uses a combination of the CERES cloud retrieval algorithm applied to MODIS data and a microwave retrieval method applied to AMSR-E data. The combination of a CO2-slicing cloud retireval technique with the CERES algorithms applied to MODIS data (Chang et al., 2005) is used to detect and analyze such overlapped systems that contain thin ice clouds. A third technique uses brightness temperature differences and the CERES algorithms to detect similar overlapped methods. This paper uses preliminary CloudSat and CALIPSO data to begin a global scale assessment of these different methods. The long-term goals are to assess and refine the algorithms to aid the development of an optimal combination of the techniques to better monitor ice 9and liquid water clouds in overlapped conditions.

  2. A preliminary evaluation of a combined tire- and refuse-derived fuel (TDF-RDF)

    SciTech Connect

    Stessel, R.I.; Amari, T.; Themelis, N.J.; Wearnick, I.K.

    1999-07-01

    In dense urban areas of the US, it is now becoming clear that waste management is far from economically-optimum. Even with the popularity of inexpensive land disposal, hauling and recycling costs are driving up the average waste bill. An historic option has been refuse-derived fuel, or RDF. Difficulties included low energy content and difficulty obtaining uniformity. Today, many resource-recovery technologies used in RDF are finding their way into materials recovery facilities (MRFs), some of which are reviving the automated processing of waste. Any MRF, automated or not, will have residue streams. Currently, one of the most significant problems is waste tires. Local options are difficult to locate in dense urban areas. As fuels, tires typically have energy contents considerably above those for which most solid-fuel combustors are designed, leading to thermal imbalances and various forms of failure. This paper suggests a new fuel that can be either co-fired with coal, or used in its own right in a combustor primarily designed for coal: TDF-RDF. A preliminary examination is undertaken of thermal and emissions characteristics, and possible costs for a few applications of the fuel. Immediately, TDF is already cleaner-burning than many coals, even in sulfur emissions. RDF has been widely-regarded as being similarly cleanly. Posited MRF residue streams should be still cleaner, and more consistent, than RDF. Overall, there is quite a potential for developing a fuel that would allow old coal powerplants in historic urban centers to be better neighbors, while helping with a few problems in municipal waste management.

  3. Evaluation of Passive Multilayer Cloud Detection Using Preliminary CloudSat and CALIPSO Cloud Profiles

    NASA Astrophysics Data System (ADS)

    Minnis, P.; Sun-Mack, S.; Chang, F.; Huang, J.; Nguyen, L.; Ayers, J. K.; Spangenberg, D. A.; Yi, Y.; Trepte, C. R.

    2005-05-01

    During the last few years, several algorithms have been developed to detect and retrieve multilayered clouds using passive satellite data. Assessing these techniques has been difficult due to the need for active sensors such as cloud radars and lidars that can "see" through different layers of clouds. Such sensors have been available only at a few surface sites and on aircraft during field programs. With the launch of the CALIPSO and CloudSat satellites on April 28, 2006, it is now possible to observe multilayered systems all over the globe using collocated cloud radar and lidar data. As part of the A- Train, these new active sensors are also matched in time ad space with passive measurements from the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) and Advanced Microwave Scanning Radiometer - EOS (AMSR-E). The Clouds and the Earth's Radiant Energy System (CERES) has been developing and testing algorithms to detect ice-over-water overlapping cloud systems and to retrieve the cloud liquid path (LWP) and ice water path (IWP) for those systems. One technique uses a combination of the CERES cloud retrieval algorithm applied to MODIS data and a microwave retrieval method applied to AMSR-E data. The combination of a CO2-slicing cloud retireval technique with the CERES algorithms applied to MODIS data (Chang et al., 2005) is used to detect and analyze such overlapped systems that contain thin ice clouds. A third technique uses brightness temperature differences and the CERES algorithms to detect similar overlapped methods. This paper uses preliminary CloudSat and CALIPSO data to begin a global scale assessment of these different methods. The long-term goals are to assess and refine the algorithms to aid the development of an optimal combination of the techniques to better monitor ice 9and liquid water clouds in overlapped conditions.

  4. Nitrate losses from fertilised short rotation willow - a preliminary evaluation of two years data

    SciTech Connect

    Reynolds, S.E.; Riddell-Block, D.M.

    1995-11-01

    The contamination of surface and ground waters arising from fertiliser use and livestock husbandry is arousing increasing concern and legislative controls on nitrogen application in vulnerable areas are being applied across the European Union. The production of wood on agricultural land is increasing as farmers diversify away from food crops. One crop which is attracting significant interest amongst farmers is the production of fuel from intensively planted willow and poplar grown on short rotations, referred to as short rotation forestry (SRF). The management of these crops is substantially less intensive than that employed in traditional agriculture. However, concerns over the potential environmental impact of the large-scale development of SRF have prompted the investigation of its water usage and influence on water quality. The opportunity was taken to conduct a preliminary investigation of nitrate leaching losses from intensively planted willow through the monitoring of a trial established to examine the fertiliser response of the crop. Two years data are reported in the poster presentation. Soil pore water samples were collected over two winters using porous ceramic suction samples installed vertically to a depth of 0.75 m beneath 18 month old stools of Salix dasyclados to which 172m{sup -3} ha{sup -1} equivalent of sewage sludge was applied in May 1993. Samplers were also installed in unfertilised control plots. Stools were spaced to give stocking densities of 20,000, 10,000 and 6,600 ha{sup -1}. Sampling commenced in November 1993 and continued at two to four week intervals until the end of May 1994. The process was repeated over the winter of 1994/95. Nitrate concentrations in soil pore water was significantly higher in the fertilised plots than under the unfertilised control in both years. However, differences were no longer significant at the end of the sampling period in either year.

  5. Preliminary evaluation of spectral, normal and meteorological crop stage estimation approaches

    NASA Technical Reports Server (NTRS)

    Cate, R. B.; Artley, J. A.; Doraiswamy, P. C.; Hodges, T.; Kinsler, M. C.; Phinney, D. E.; Sestak, M. L. (Principal Investigator)

    1980-01-01

    Several of the projects in the AgRISTARS program require crop phenology information, including classification, acreage and yield estimation, and detection of episodal events. This study evaluates several crop calendar estimation techniques for their potential use in the program. The techniques, although generic in approach, were developed and tested on spring wheat data collected in 1978. There are three basic approaches to crop stage estimation: historical averages for an area (normal crop calendars), agrometeorological modeling of known crop-weather relationships agrometeorological (agromet) crop calendars, and interpretation of spectral signatures (spectral crop calendars). In all, 10 combinations of planting and biostage estimation models were evaluated. Dates of stage occurrence are estimated with biases between -4 and +4 days while root mean square errors range from 10 to 15 days. Results are inconclusive as to the superiority of any of the models and further evaluation of the models with the 1979 data set is recommended.

  6. Evaluation of Siddha Samadhi Yoga for anxiety and depression symptoms: a preliminary study.

    PubMed

    Kozasa, Elisa Harumi; Santos, Ruth Ferreira; Rueda, Adriana Dourado; Benedito-Silva, Ana Amélia; De Ornellas, Felipe Leite Moraes; Leite, José Roberto

    2008-08-01

    Siddha Samadhi Yoga is a program in which meditation is associated with pranayama (breathing exercises). 22 volunteers with anxiety complaints (M age = 42.8 yr., SD = 10.3) were assigned to two groups: 14 attended the yoga group, and 8 attended a waiting-list or control group. They were evaluated before the intervention and 1 month after it on the State-Trait Anxiety Inventory, the Beck Depression Inventory, Tension Feelings Self-evaluation Scales, and the Well-being Self-evaluation Scales. A significant reduction in scores on anxiety, depression, and tension was found in yoga group, as well as an increase in well-being in comparison with the control group.

  7. Development and Preliminary Evaluation of Aryl Ester Boundary Additives for Perfluoropolyethers

    NASA Technical Reports Server (NTRS)

    Williams, John R.; Feuchter, Debra K.; Jones, William R., Jr.

    1994-01-01

    A series of additives were developed for evaluation as boundary lubrication enhancers for perfluoropolyethers. They are composed of a hydrocarbon aryl component (for lubrication improvement) and a fluorinated side chain (for solubility enhancement). The two moieties are joined by an ester linkage. Five boundary additives were evaluated in a perfluoropolyether basestock (Fomblin Z25) using a specially designed four-ball apparatus. Additives were evaluated at a one wt percent concentration. Conditions included: an atmosphere of dry air at atmospheric pressure, a 200N load, a speed of 100 rpm, room temperature, and 440C stainless steel specimens. Two monoesters, 2,4,6-trimethyl E2 and H5PDFO yielded wear rate reductions of approximately 60 and 35 percent, respectively. One diester, H4(E2)(sub 2), had no activity, while two other diesters (a diester of bisphenol A and H4(E4)(sub 2)) were pro-wear.

  8. Preliminary evaluation of selected in situ remediation technologies for Volatile Organic Compound contamination at Arid sites

    SciTech Connect

    Lenhard, R.J.; Gerber, M.A.; Amonette, J.E.

    1992-10-01

    To support the Volatile Organic Compounds-Arid Site (VOC-Arid) Integrated Demonstration (ID) in its technical, logistical, institutional, and economical testing of emerging environmental management and restoration technologies. Pacific Northwest Laboratory(a) is evaluating several in situ remediation technologies for possible inclusion in the demonstration. The evaluations are made with respect to the initial focus of the VOC-Arid ID: the carbon tetrachloride contamination at the Hanford Site, where it was disposed to the vadose zone along with other volatile and nonvolatile organic wastes. heavy metals, acids. and radionuclides. The purposes of this report are (1) to identify candidate in situ technologies for inclusion in the program, (2) to evaluate the candidate technologies based on their potential applicability to VOC contamination at arid sites and geologic conditions representative of the ID host site (i.e., Hanford Site), and (3) to prioritize those technologies for future US Department of Energy (DOE) support.

  9. Preliminary Findings of an Evaluation of COSTAR in a Community Health Center

    PubMed Central

    Fiddleman, Richard

    1980-01-01

    COSTAR is a powerful and flexible information system designed for widespread use by ambulatory health care organizations. An ambitious installation of the system has been undertaken in a community health center located in Southern California. At this site, virtually all medical record data have been automated, and the system is used to support most of the organization's financial, administrative, medical records, and quality-of-care activities. An evaluation of the system's costs and benefits after one year of operation is currently underway. The evaluation methodology being used and findings to date are presented. Additional findings will be presented at the conference.

  10. Preliminary Evaluation of Greases for Space Mechanisms Using a Vacuum Spiral Orbit Tribometer

    NASA Technical Reports Server (NTRS)

    Marchetti, Mario; Jones, William R., Jr.; Street, Kenneth W.; Pepper, Stephen V.; Jansen, Mark J.

    2001-01-01

    Most currently used greases for space applications are based on perfluoropolyalkylethers (PFPE) and multiply alkylated cyclopentane (MAC) oils. Evaluation of the greases includes outgassing properties, rheological behavior, and particularly the ability to create EHL films under conditions as close as possible to an actual application. A spiral orbit tribometer (SOT) has been developed to conduct accelerated tests under realistic conditions. The SOT was employed to evaluate two greases used in space mechanisms: a PFPE oil with polytetrafluoroethylene (PTFE) thickener, and a multiply alkylated cyclopentane oil with n-octadecylterephthalamate soap. The results from the greases are in agreement with results previously obtained with the base oils.

  11. Preliminary report on the evaluation of selected ultrasonic and gyroscopic flowmeters at cryogenic temperatures. Final report

    SciTech Connect

    Brennan, J.A.; Takano, A.

    1982-01-01

    Several ultrasonic and gyroscopic flowmeters were tested on the cyrogenic flow facility at the National Bureau of Standards (NBS) in Boulder, Colorado. Meters were evaluated using liquid nitrogen with flow rates with temperatures ranging from 0.13 to 2.25 liters/second for small meters and from 1.45 to 13.1 liters/second for a larger meter, with pressures ranging from 0.41 to 0.80 MPa and 79 to 91 K. Results for the test showed flowmeters evaluated, with one exception, their applicability to cryogenic service with appropriate consideration of their characteristics at low temperatures.

  12. Neutron spectral measurements in the upper atmosphere

    NASA Technical Reports Server (NTRS)

    Zobel, W.; Love, T. A.; Delorenzo, J. T.; Mcnew, C. O.

    1972-01-01

    An experiment to measure neutrons in the upper atmosphere was performed on a balloon flight from Palestine, Texas, at an altitude of about 32 km. The experimental arrangement is discussed briefly, and results of a preliminary analysis of the data for neutrons in the energy range 3 to 30 MeV are given.

  13. A preliminary multi-stable-isotopic evaluation of three synthetic pathways of Topiramate.

    PubMed

    Jasper, J P; Weaner, L E; Duffy, B J

    2005-09-01

    As a preliminary study of the utility of the natural stable-isotopic differentiation of batch samples produced by different synthetic pathways, multi-stable-isotopic analyses (delta(13)C, delta(15)N, delta(18)O, deltaD) of 53 samples of the antiepileptic drug, Topiramate, produced by three different synthetic pathways (designated "A," "B," "C") were performed. From the outset, we note that there are two fundamental variables that determine the stable-isotopic composition of materials-the stable-isotopic composition of the reagents and starting intermediates, and the isotope fractionation that occurs during manufacture of the product. In this study, the stable-isotopic composition of the raw materials was not controlled and we report here data obtained for a suite of samples that was produced by three synthetic pathways. Graphical examination of these data reveals marked data clustering by synthetic pathway, though in some cases with some overlapping values within standard errors. In general, the isotopic composition of Topiramate from the A and B pathways is distinct from the C pathway. The isotopic data from the A and B pathways typically abut each other, sometimes partially overlapping. The deuterium/hydrogen- (deltaD) and oxygen (delta(18)O) isotopic compositions are each significantly linearly related with the paired carbon (delta(13)C) isotopic composition indicating possible isotopic end-members for the raw materials of the present sample suite. Given that H and O typically derive from meteoric water, the linear correlations with delta(13)C indicate that a mixture of carbon sources (viz., perhaps terrestrial C3 photosynthetic organic carbon and marine C3 organic carbon) were used in the production of the batches tested. If the H and O analyzed were derived from meteoric water, then an elementary comparison of the span of the deltaD (DeltadeltaD = 54.6 +/- 2.1 per thousand) and of the delta(18)O (Deltadelta(18)O = 4.71 +/- 0.26 per thousand) values in the

  14. Hyperacuity test to evaluate vision through dense cataracts: research preliminary to a clinical study in India

    NASA Astrophysics Data System (ADS)

    Enoch, Jay M.; Giraldez, Maria J.; Huang, Doahua; Hirose, Hiroshi; Knowles, Richard A.; Namperumalsamy, P.; LaBree, Lauri; Azen, Stanley P.

    1995-03-01

    Using high luminance point-of-light stimuli, Vernier judgments can be made in the presence of markedly degraded retinal imagery. Without coaching, observers perform center-of-gravity assessments of relative locations of degraded point images. We seek to defined, presurgery, individuals who will derive the most benefit from advanced cataract removal (a form of triage), and to determine which of two cataractous eyes has the better postsurgical visual prognosis. There are incredible and growing backlogs of patients with severe cataracts (and other dense media opacities) in the developing world, and generally, limited resources are available for provision of health care. Postcataract surgical failure rates for good visual function are often high, and only one eye is operated on in over 95% of indigent patients treated. Prior to initiating advanced studies in the developing world, at Berkeley we conducted preliminary research on Vernier acuity test techniques on normal adult subjects. We sought to determine the number of repeat trials necessary; to compare a two-point and a three-point Vernier display; to determine the shape of the measured response function at large gap separations between test points (required when testing advanced cataract patients); to assess the effect(s) of a broad range of uncorrected refractive errors on outcomes; and to consider means to minimize refraction-based errors. From these and prior data and analyses, we defined a protocol for use in the developing world. Using a newly designed and rugged precision instrument, these tests were repeated on an advanced cataract population at Aravind Eye Hospital in Madurai, India. Although we had much prior experience in India, the initial protocol required major revision on site. Necessary changes in test methods and analytical approaches were made, and next stages in this program were planned. And a new and simple gap `visual acuity' (gap `VA') test was added to the protocol, which greatly facilitated

  15. Postural Stability During Single-Leg Stance: A Preliminary Evaluation of Noncontact Lower Extremity Injury Risk.

    PubMed

    Dingenen, Bart; Malfait, Bart; Nijs, Stefaan; Peers, Koen H E; Vereecken, Styn; Verschueren, Sabine M P; Janssens, Luc; Staes, Filip F

    2016-08-01

    Study Design Controlled laboratory study with a prospective cohort design. Background Postural stability deficits during single-leg stance have been reported in persons with anterior cruciate ligament (ACL) injury, ACL reconstruction, and chronic ankle instability. It remains unclear whether impaired postural stability is a consequence or cause of these injuries. Objectives To prospectively investigate whether postural stability deficits during single-leg stance predict noncontact lower extremity injuries. Methods Fifty injury-free female athletes performed a transition task from double-leg stance to single-leg stance with eyes closed. Center-of-pressure displacement, the main outcome variable, was measured during the first 3 seconds after the time to a new stability point was reached during single-leg stance. Noncontact lower extremity injuries were recorded at a 1-year follow-up. Results Six participants sustained a noncontact ACL injury or ankle sprain. Center-of-pressure displacement during the first 3 seconds after the time to a new stability point was significantly increased in the injured (P = .030) and noninjured legs (P = .009) of the injured group compared to the respective matched legs of the noninjured group. The area under the receiver operating characteristic curve (AUC) analysis revealed significant discriminative accuracy between groups for the center-of-pressure displacement during the first 3 seconds after the time to a new stability point of the injured (AUC = 0.814, P = .015) and noninjured legs (AUC = 0.897, P = .004) of the injured group compared to the matched legs of the noninjured group. Conclusion This preliminary study suggests that postural stability measurements during the single-leg stance phase of the double- to single-leg stance transition task may be a useful predictor of increased risk of noncontact lower extremity injury. Further research is indicated. Level of Evidence Prognosis, level 4. J Orthop Sports PhysTher 2016

  16. Preliminary evaluation of daylily cultivars for rust resistance in a landscaping setting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A large, established landscape collection of 575 newer cultivars was evaluated for daylily rust which had not been sprayed with fungicides to prevent infection during 2013. The warm, damp summer of 2013 was ideal for spread of daylily rust. A total of 119 of the 575 cultivars received a median ratin...

  17. Preliminary Evaluation of a University-Based Suicide Intervention Project: Impact on Participants.

    ERIC Educational Resources Information Center

    Pearce, Katie; Rickwood, Debra; Beaton, Susan

    2003-01-01

    Study evaluated the peer-based Suicide Intervention Project (SIP) in terms of changes experienced by its first participants. Improvements were expected in attitudes, norms, perceived behavioral control, self efficacy and intentions toward talking to other university students about personal feelings and mental health problems. Results are discussed…

  18. Preliminary Evaluation of Children's Psychosocial Rehabilitation for Youth with Serious Emotional Disturbance

    ERIC Educational Resources Information Center

    Williams, Nathaniel J.

    2009-01-01

    Objective: This article introduces and evaluates children's psychosocial rehabilitation, a home- and community-based treatment for children with serious emotional disturbance. Method: In an open-trial design, the author used repeated-measures analysis of variance and Wilcoxon signed-rank tests to assess pre-post outcome ratings for 218…

  19. A Preliminary Evaluation of Instructional Effectiveness of Online Training Implemented at a Government Agency in Thailand

    ERIC Educational Resources Information Center

    Supanakorn-Davila, Supawan; Bolliger, Doris U.

    2012-01-01

    Online training has become popular in the professional development of government employees in Thailand. One large government agency developed an online program to provide training to its employees across the country using two systems: an Internet and Intranet-based system. With the new program implemented, the evaluation of the instructional…

  20. The Evaluation of Student Achievement: Preliminary Analyses in Modelling Teacher Decisions.

    ERIC Educational Resources Information Center

    Anderson, John O.

    This study focused on one task that is characteristic of teacher responsibilities and activities in the school: the evaluation of student achievement. It involved more than 100 preservice elementary school teachers who assessed the performance of 3 simulated students on 6 language arts tasks. Information collected included the marks assigned to…

  1. Preliminary evaluation of the Accident Response Mobile Manipulation System for accident site salvage operations

    SciTech Connect

    Trujillo, J.M.; Morse, W.D.; Jones, D.P.

    1994-10-01

    This paper describes and evaluates operational experiences with the Accident Response Mobile Manipulation System (ARMMS) during simulated accident site salvage operations which might involve nuclear weapons. The ARMMS is based upon a teleoperated mobility platform with two Schilling Titan 7F Manipulators.

  2. Preliminary Evaluation of an Educational Outcomes Assessment Process for Dental Interpretive Radiography.

    ERIC Educational Resources Information Center

    Weems, Richard A.; And Others

    1992-01-01

    A procedure for testing the ability of dental students to detect presence and depth of dental caries was evaluated. Students (n=40) from four experience groups examined radiographs obtained from a model. Results indicated that this method of assessing student competence in radiographic interpretation is valid. (MSE)

  3. Preliminary Evaluation of the Childhood Experiences of Violence Questionnaire Short Form

    ERIC Educational Resources Information Center

    Tanaka, Masako; Wekerle, Christine; Leung, Eman; Waechter, Randall; Gonzalez, Andrea; Jamieson, Ellen; MacMillan, Harriet L.

    2012-01-01

    Despite advances in child maltreatment research, accurate measurement of exposure remains a key issue. In this study, we evaluated a short form (CEVQ-SF) of the Childhood Experiences of Violence Questionnaire (CEVQ) in a sample of adolescents involved with child protection services in an urban city in Ontario, Canada. Focusing on the two most…

  4. The Preventing Relational Aggression in Schools Everyday Program: A Preliminary Evaluation of Acceptability and Impact

    ERIC Educational Resources Information Center

    Leff, Stephen S.; Waasdorp, Tracy Evian; Paskewich, Brooke; Gullan, Rebecca Lakin; Jawad, Abbas F.; MacEvoy, Julie Paquette; Feinberg, Betsy E.; Power, Thomas J.

    2010-01-01

    Despite recent research suggesting that relationally aggressive behaviors occur frequently and may lead to physically aggressive actions within urban school settings, there has been little prior research to develop and evaluate relational aggression prevention efforts within the urban schools. The current article describes the development and…

  5. Preliminary evaluation of AERMOD using site specific stack and ambient sampling data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A cotton ginning industry-supported project was initiated in 2008 to develop a robust particulate matter (PM) dispersion modeling dataset that could be used for evaluating current and future PM dispersion models. This paper compares total PM data collected by the industry-supported study at one gin ...

  6. Preliminary Evaluation of a Parent Training Program to Prevent Gun Play

    ERIC Educational Resources Information Center

    Gross, Amy; Miltenberger, Raymond; Knudson, Peter; Bosch, Amanda; Breitwieser, Carrie Brower

    2007-01-01

    Recent research has shown that behavioral skills training with in situ training is an effective strategy to teach children the safety skills needed if they ever encounter an unattended firearm. The current study evaluated the use of parents as trainers to increase the efficiency of training. The success of parent training on their children's…

  7. Evaluating Interventions for Young Gifted Children Using Single-Subject Methodology: A Preliminary Study

    ERIC Educational Resources Information Center

    Walsh, Rosalind L.; Kemp, Coral

    2013-01-01

    Single-subject experimental designs have long been used in special education to evaluate the effectiveness of interventions for exceptional children. However, the design has not been used widely in gifted education. In this article, an overview of the main features of single-subject design is presented, and its potential for application in gifted…

  8. Preliminary Study on Establishing the New System of Assessment and Evaluation Of "Athletic Physiology"

    ERIC Educational Resources Information Center

    Qian, Liu

    2012-01-01

    In the light of the problems existing in assessment of the course of "athletic physiology" in universities at present, this article makes reflections upon the assessment mode of students for this course and takes a general survey on development of the evaluation system by comprehensively employing both the quantitative method and…

  9. Clinical Problem Solving Exercises for Pre-Clinical Medical Education: A Design, Implementation and Preliminary Evaluation.

    ERIC Educational Resources Information Center

    Bordage, Georges

    Clinical problem solving exercises for preclinical medical education that were developed at Michigan State University School of Osteopathic Medicine are described. Two types of outcomes were set as priorities in the design and implementation of the problem solving sessions: small group peer interactions as instructional and evaluative resources;…

  10. A New Module for Large Scale Bayesian Evaluation in the Fast Neutron Energy Region

    SciTech Connect

    Schnabel, G. Leeb, H.

    2015-01-15

    We present an improved update scheme for the Linearized Bayesian Update procedure (LBUP). The revised procedure extends the application of the LBUP to a large number of observables. The consistent update of dozens of millions of observables becomes manageable by circumventing the costly calculation of the prior covariance matrix. Nuclear data evaluations based on the revised scheme may exhaustively enclose all differential and angle-integrated channels, treating all correlations between them exactly in the update procedure.

  11. Neutron activation and other analytical data for plutonic rocks from North America and Africa. National Uranium Resource Evaluation

    SciTech Connect

    Price, V.; Fay, W.M.; Cook, J.R.

    1982-09-01

    The objective of this report is to retrieve the elements of an analytical study of granites and associated other plutonic rocks which was begun as a part of the U.S. Department of Energy's National Uranium Resource Evaluation (NURE) program. A discussion of the Savannah River Laboratory (SRL) neutron activation analysis system is given so that a user will understand the linmitations of the data. Enough information is given so that an experienced geochemist can clean up the data set to the extent required by any project. The data are generally good as they are presented. It is intended that the data be read from a magnetic tape written to accompany this report. Microfiche tables of the data follow the text. These tables were prepared from data on the tape, and programs which will read the tape are presented in the section THE DATA TAPE. It is our intent to write a later paper which will include a thoroughly scrubbed data set and a technical discussion of results of the study. 1 figure.

  12. Synthesis and evaluation of thymidine kinase 1-targeting carboranyl pyrimidine nucleoside analogues for boron neutron capture therapy of cancer

    PubMed Central

    Agarwal, Hitesh K.; Khalil, Ahmed; Ishita, Keisuke; Yang, Weilian; Nakkula, Robin J.; Wu, Lai-Chu; Ali, Tehane; Tiwari, Rohit; Byun, Youngjoo; Barth, Rolf F.; Tjarks, Werner

    2015-01-01

    A library of sixteen 2nd generation amino- and amido-substituted carboranyl pyrimidine nucleoside analogues, designed as substrates and inhibitors of thymidine kinase 1 (TK1) for potential use in boron neutron capture therapy (BNCT) of cancer, was synthesized and evaluated in enzyme kinetic-, enzyme inhibition-, metabolomic-, and biodistribution studies. One of these 2nd generation carboranyl pyrimidine nucleoside analogues (YB18A [3]), having an amino group directly attached to a meta-carborane cage tethered via ethylene spacer to the 3-position of thymidine, was approximately 3–4 times superior as a substrate and inhibitor of hTK1 than N5-2OH (2), a 1st generation carboranyl pyrimidine nucleoside analogue. Both 2 and 3 appeared to be 5′-monophosphorylated in TK1(+) RG2 cells, both in vitro and in vivo. Biodistribution studies in rats bearing intracerebral RG2 glioma resulted in selective tumor uptake of 3 with an intratumoral concentration that was approximately 4 times higher than that of 2. The obtained results significantly advance the understanding of the binding interactions between TK1 and carboranyl pyrimidine nucleoside analogues and will profoundly impact future design strategies for these agents. PMID:26087030

  13. NEUTRON AND NON-NEUTRON NUCLEAR DATA FOR RADIATION DOSIMETRY

    SciTech Connect

    HOLDEN,N.E.

    1999-09-10

    NEUTRON NUCLEAR DATA THAT IS USED IN REACTOR DOSIMETRY INCLUDE THERMAL NEUTRON CROSS SECTIONS AND NEUTRON RESONANCE INTEGRALS, FISSION SPECTRUM AVERAGED CROSS SECTIONS FOR REACTIONS ON A TARGET NUCLEUS. NON-NEUTRON NUCLEAR DATA USED IN REACTOR DOSIMETRY INCLUDE ISOTOPIC COMPOSITIONS OF TARGET NUCLIDES AND RADIOACTIVE HALF-LIVES, GAMMA-RAY ENERGIES AND INTENSITIES OF REACTION PRODUCT NUCLIDES. ALL OF THESE DATA ARE PERIODICALLY EVALUATED AND RECOMMENDED VALUES ARE PROVIDED IN THE HANDBOOK OF CHEMISTRY AND PHYSICS. THE LATEST RECOMMENDED VALUES ARE DISCUSSED AND THEY ARE CONTRASTED WITH SOME EARLIER NUCLEAR DATA, WHICH WAS PROVIDED WITH NEUTRON DETECTOR FOILS.

  14. Use of Web 2.0 Social Media Platforms to Promote Community-Engaged Research Dialogs: A Preliminary Program Evaluation

    PubMed Central

    Valdez Soto, Miguel; Bishop, Shawn G; Aase, Lee A; Timimi, Farris K; Montori, Victor M; Patten, Christi A

    2016-01-01

    Background Community-engaged research is defined by the Institute of Medicine as the process of working collaboratively with groups of people affiliated by geographic proximity, special interests, or similar situations with respect to issues affecting their well-being. Traditional face-to-face community-engaged research is limited by geographic location, limited in resources, and/or uses one-way communications. Web 2.0 technologies including social media are novel communication channels for community-engaged research because these tools can reach a broader audience while promoting bidirectional dialogs. Objective This paper reports on a preliminary program evaluation of the use of social media platforms for promoting engagement of researchers and community representatives in dialogs about community-engaged research. Methods For this pilot program evaluation, the Clinical and Translational Science Office for Community Engagement in Research partnered with the Social Media Network at our institution to create a WordPress blog and Twitter account. Both social media platforms were facilitated by a social media manager. We used descriptive analytics for measuring engagement with WordPress and Twitter over an 18-month implementation period during 2014-2016. For the blog, we examined type of user (researcher, community representative, other) and used content analysis to generate the major themes from blog postings. For use of Twitter, we examined selected demographics and impressions among followers. Results There were 76 blog postings observed from researchers (48/76, 64%), community representatives (23/76, 32%) and funders (5/76, 8%). The predominant themes of the blog content were research awareness and dissemination of community-engaged research (35/76, 46%) and best practices (23/76, 30%). For Twitter, we obtained 411 followers at the end of the 18-month evaluation period, with an increase of 42% (from 280 to 411) over the final 6 months. Followers reported varied

  15. Shelf-life evaluation of Kaṃsaharītakī avaleha and its granules: A preliminary study

    PubMed Central

    Khemuka, Nidhi; Galib, R.; Patgiri, B. J.; Prajapati, Pradeep Kumar

    2015-01-01

    Background: Savīryatā-avadhi (shelf life) of different Ayurvedic dosage forms is described in Śārṅgadharasaṃhitā. Though the concepts have a strong background, we seek to re-evaluate the age old concepts by following current norms. An attempt has been made in the present study to evaluate shelf-life of Kaṃsaharītakī avaleha and its granules. Materials and Methods: Raw materials were procured from Pharmacy, Gujarat Ayurved University, Jamnagar and utilized after proper authentication in pharmacognosy lab. The avaleha and its granules were prepared in the departmental laboratory following classical guidelines and subjected to accelerated stability studies. Results: Both the products were found to be free from microbial contamination. Heavy metals were within the prescribed limit. Changes in physico-chemical profiles at different intervals are insignificant. On extrapolation of the observations, the shelf life of avaleha was found to be18 months and 27 months to the granules. Conclusion: Stability of granules was found to be comparatively higher than the avaleha. This observation may be exclusive to Kaṃsaharītakī avaleha. Studies on other avalehas and their granules need to be carried out to confirm this preliminary observation. PMID:26865742

  16. Preliminary Evaluation of the Field and Laboratory Emission Cell (FLEC) for Sampling Attribution Signatures from Building Materials

    SciTech Connect

    Harvey, Scott D.; He, Lijian; Wahl, Jon H.

    2012-08-30

    This study provides a preliminary evaluation of the Field and Laboratory Emission Cell (FLEC) for its suitability for sampling building materials for toxic compounds and their associated impurities and residues that might remain after a terrorist chemical attack. Chemical warfare (CW) agents and toxic industrial chemicals were represented by a range of test probes that included CW surrogates. The test probes encompassed the acid-base properties, volatilities, and polarities of the expected chemical agents and residual compounds. Results indicated that dissipation of the test probes depended heavily on the underlying material. Near complete dissipation of almost all test probes occurred from galvanized stainless steel within 3.0 hrs, whereas far stronger retention with concomitant slower release was observed for vinyl composition floor tiles. The test probes displayed immediated permanence on Teflon. FLEC sampling was further evaluated by profiling residues remaining after the evaporation of 2-chloroethyl ethyl sulfide, a sulfur mustard simulant. This study lays the groundwork for the eventual goal of applying this sampling approach for collection of forensic attribution signatures that remain after a terrorist chemical attack.

  17. Preliminary In Vitro and In Vivo Evaluation of Antidiabetic Activity of Ducrosia anethifolia Boiss. and Its Linear Furanocoumarins

    PubMed Central

    Shalaby, Nagwa M. M.; Abd-Alla, Howaida I.; Aly, Hanan F.; Albalawy, Marzougah A.; Shaker, Kamel H.; Bouajila, Jalloul

    2014-01-01

    Aim. Ducrosia anethifolia is used as flavoring additive. There have been little detailed phytochemical reports on this genus and the antidiabetic activity of this plant is not yet evaluated. Method. Structure of compounds was deduced by spectroscopic analyses. Preliminary in vitro evaluation of the antidiabetic activity of crude extract and its furanocoumarins was carried out (α-amylase, α-glucosidase, and β-galactosidase). The in vivo activity was investigated by measuring some oxidative stress markers. Biomarkers of liver injury and kidney were also determined. Results. Eight linear furanocoumarins, psoralen, 5-methoxypsoralen, 8-methoxypsoralen, imperatorin, isooxypeucedanin, pabulenol, oxypeucedanin methanolate, oxypeucedanin hydrate, and 3-O-glucopyranosyl-β-sitosterol, were isolated. All compounds were reported for the first time from the genus Ducrosia except pabulenol. The blood glucose level, liver function enzymes, total protein, lipid, and cholesterol levels were significantly normalized by extract treatment. The antioxidant markers, glucolytic, and gluconeogenic enzymes were significantly ameliorated and the elevated level of kidney biomarkers in the diabetic groups was restored. The compounds showed inhibitory activity in a concentration dependant manner. Imperatorin and 5-methoxypsoralen showed the most potent inhibiting power. Conclusion. D. anethifolia extract showed hypoglycemic, hypolipidemic, and antioxidant effect as well as ameliorating kidney function. This extract and some linear furanocoumarins exhibited carbohydrate metabolizing enzymes inhibitory effect. PMID:24800231

  18. Worldwide Evaluations of Quinoa: Preliminary Results from Post International Year of Quinoa FAO Projects in Nine Countries.

    PubMed

    Bazile, Didier; Pulvento, Cataldo; Verniau, Alexis; Al-Nusairi, Mohammad S; Ba, Djibi; Breidy, Joelle; Hassan, Layth; Mohammed, Maarouf I; Mambetov, Omurbek; Otambekova, Munira; Sepahvand, Niaz Ali; Shams, Amr; Souici, Djamel; Miri, Khaled; Padulosi, Stefano

    2016-01-01

    Chenopodium quinoa Willd., a high quality grain crop, is resistant to abiotic stresses (drought, cold, and salt) and offers an optimal source of protein. Quinoa represents a symbol of crop genetic diversity across the Andean region. In recent years, this crop has undergone a major expansion outside its countries of origin. The activities carried out within the framework of the International Year of Quinoa provided a great contribution to raise awareness on the multiple benefits of quinoa as well as to its wider cultivation at the global level. FAO is actively involved in promoting and evaluating the cultivation of quinoa in 26 countries outside the Andean region with the aim to strengthen food and nutrition security. The main goal of this research is to evaluate the adaptability of selected quinoa genotypes under different environments outside the Andean region. This paper presents the preliminary results from nine countries. Field evaluations were conducted during 2013/2014 and 2014/2015 in Asia (Kyrgyzstan and Tajikistan), and the Near East and North African countries (Algeria, Egypt, Iraq, Iran, Lebanon, Mauritania, and Yemen). In each country, the trials were carried out in different locations that globally represent the diversity of 19 agrarian systems under different agro-ecological conditions. Twenty-one genotypes of quinoa were tested using the same experimental protocol in all locations consisting in a randomized complete block design (RCBD) with three replicates. Some genotypes showed higher yields and the Q18 and Q12 landraces displayed greater adaptation than others to new environmental conditions. The Q21 and Q26 landraces were evaluated with stable and satisfactory levels of yield (>1 t.ha(-1)) in each of the different trial sites. This production stability is of considerable importance especially under climate change uncertainty. While these results suggest that this Andean crop is able to grow in many different environments, social, and cultural

  19. Worldwide Evaluations of Quinoa: Preliminary Results from Post International Year of Quinoa FAO Projects in Nine Countries

    PubMed Central

    Bazile, Didier; Pulvento, Cataldo; Verniau, Alexis; Al-Nusairi, Mohammad S.; Ba, Djibi; Breidy, Joelle; Hassan, Layth; Mohammed, Maarouf I.; Mambetov, Omurbek; Otambekova, Munira; Sepahvand, Niaz Ali; Shams, Amr; Souici, Djamel; Miri, Khaled; Padulosi, Stefano

    2016-01-01

    Chenopodium quinoa Willd., a high quality grain crop, is resistant to abiotic stresses (drought, cold, and salt) and offers an optimal source of protein. Quinoa represents a symbol of crop genetic diversity across the Andean region. In recent years, this crop has undergone a major expansion outside its countries of origin. The activities carried out within the framework of the International Year of Quinoa provided a great contribution to raise awareness on the multiple benefits of quinoa as well as to its wider cultivation at the global level. FAO is actively involved in promoting and evaluating the cultivation of quinoa in 26 countries outside the Andean region with the aim to strengthen food and nutrition security. The main goal of this research is to evaluate the adaptability of selected quinoa genotypes under different environments outside the Andean region. This paper presents the preliminary results from nine countries. Field evaluations were conducted during 2013/2014 and 2014/2015 in Asia (Kyrgyzstan and Tajikistan), and the Near East and North African countries (Algeria, Egypt, Iraq, Iran, Lebanon, Mauritania, and Yemen). In each country, the trials were carried out in different locations that globally represent the diversity of 19 agrarian systems under different agro-ecological conditions. Twenty-one genotypes of quinoa were tested using the same experimental protocol in all locations consisting in a randomized complete block design (RCBD) with three replicates. Some genotypes showed higher yields and the Q18 and Q12 landraces displayed greater adaptation than others to new environmental conditions. The Q21 and Q26 landraces were evaluated with stable and satisfactory levels of yield (>1 t.ha−1) in each of the different trial sites. This production stability is of considerable importance especially under climate change uncertainty. While these results suggest that this Andean crop is able to grow in many different environments, social, and cultural

  20. Worldwide Evaluations of Quinoa: Preliminary Results from Post International Year of Quinoa FAO Projects in Nine Countries.

    PubMed

    Bazile, Didier; Pulvento, Cataldo; Verniau, Alexis; Al-Nusairi, Mohammad S; Ba, Djibi; Breidy, Joelle; Hassan, Layth; Mohammed, Maarouf I; Mambetov, Omurbek; Otambekova, Munira; Sepahvand, Niaz Ali; Shams, Amr; Souici, Djamel; Miri, Khaled; Padulosi, Stefano

    2016-01-01

    Chenopodium quinoa Willd., a high quality grain crop, is resistant to abiotic stresses (drought, cold, and salt) and offers an optimal source of protein. Quinoa represents a symbol of crop genetic diversity across the Andean region. In recent years, this crop has undergone a major expansion outside its countries of origin. The activities carried out within the framework of the International Year of Quinoa provided a great contribution to raise awareness on the multiple benefits of quinoa as well as to its wider cultivation at the global level. FAO is actively involved in promoting and evaluating the cultivation of quinoa in 26 countries outside the Andean region with the aim to strengthen food and nutrition security. The main goal of this research is to evaluate the adaptability of selected quinoa genotypes under different environments outside the Andean region. This paper presents the preliminary results from nine countries. Field evaluations were conducted during 2013/2014 and 2014/2015 in Asia (Kyrgyzstan and Tajikistan), and the Near East and North African countries (Algeria, Egypt, Iraq, Iran, Lebanon, Mauritania, and Yemen). In each country, the trials were carried out in different locations that globally represent the diversity of 19 agrarian systems under different agro-ecological conditions. Twenty-one genotypes of quinoa were tested using the same experimental protocol in all locations consisting in a randomized complete block design (RCBD) with three replicates. Some genotypes showed higher yields and the Q18 and Q12 landraces displayed greater adaptation than others to new environmental conditions. The Q21 and Q26 landraces were evaluated with stable and satisfactory levels of yield (>1 t.ha(-1)) in each of the different trial sites. This production stability is of considerable importance especially under climate change uncertainty. While these results suggest that this Andean crop is able to grow in many different environments, social, and cultural

  1. Gamma/neutron competition above the neutron separation energy in delayed neutron emitters

    NASA Astrophysics Data System (ADS)

    Valencia, E.; Algora, A.; Tain, J. L.; Rice, S.; Agramunt, J.; Zakari-Issoufou, A.-A.; Äystö, J.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Eloma, V.; Eronen, T.; Estevez, E.; Farrelly, G. F.; Fallot, M.; Garcia, A.; Gelletly, W.; Gomez-Hornillos, M. B.; Gorlychev, V.; Hakala, J.; Jokinen, A.; Jordan, M. D.; Kankainen, A.; Kondev, F. G.; Martinez, T.; Mendoza, E.; Molina, F.; Moore, I.; Perez, A.; Podolyak, Zs.; Penttilä, H.; Porta, A.; Regan, P. H.; Rissanen, J.; Rubio, B.; Weber, C.

    2014-03-01

    To study the β-decay properties of some well known delayed neutron emitters an experiment was performed in 2009 at the IGISOL facility (University of Jyväskylä in Finland) using Total Absorption γ-ray Spectroscopy (TAGS) technique. The aim of these measurements is to obtain the full β-strength distribution below the neutron separation energy (Sn) and the γ/neutron competition above. This information is a key parameter in nuclear technology applications as well as in nuclear astrophysics and nuclear structure. Preliminary results of the analysis show a significant γ-branching ratio above Sn.

  2. Preliminary evaluation of adhesion strength measurement devices for ceramic/titanium matrix composite bonds

    NASA Technical Reports Server (NTRS)

    Pohlchuck, Bobby; Zeller, Mary V.

    1992-01-01

    The adhesive bond between ceramic cement and a titanium matrix composite substrate to be used in the National Aerospace Plane program is evaluated. Two commercially available adhesion testers, the Sebastian Adherence Tester and the CSEM REVETEST Scratch Tester, are evaluated to determine their suitability for quantitatively measuring adhesion strength. Various thicknesses of cements are applied to several substrates, and bond strengths are determined with both testers. The Sabastian Adherence Tester has provided limited data due to an interference from the sample mounting procedure, and has been shown to be incapable of distinguishing adhesion strength from tensile and shear properties of the cement itself. The data from the scratch tester has been found to be difficult to interpret due to the porosity and hardness of the cement. Recommendations are proposed for a more reliable adhesion test method.

  3. Computer–Based Procedures for Nuclear Power Plant Field Workers: Preliminary Results from Two Evaluation Studies

    SciTech Connect

    Katya L Le Blanc; Johanna H Oxstrand

    2013-10-01

    The Idaho National Laboratory and participants from the U.S. nuclear industry are collaborating on a research effort aimed to augment the existing guidance on computer-based procedure (CBP) design with specific guidance on how to design CBP user interfaces such that they support procedure execution in ways that exceed the capabilities of paper-based procedures (PBPs) without introducing new errors. Researchers are employing an iterative process where the human factors issues and interface design principles related to CBP usage are systematically addressed and evaluated in realistic settings. This paper describes the process of developing a CBP prototype and the two studies conducted to evaluate the prototype. The results indicate that CBPs may improve performance by reducing errors, but may increase the time it takes to complete procedural tasks.

  4. A preliminary study of MR sickness evaluation using visual motion aftereffect for advanced driver assistance systems.

    PubMed

    Nakajima, Sawako; Ino, Shuichi; Ifukube, Tohru

    2007-01-01

    Mixed Reality (MR) technologies have recently been explored in many areas of Human-Machine Interface (HMI) such as medicine, manufacturing, entertainment and education. However MR sickness, a kind of motion sickness is caused by sensory conflicts between the real world and virtual world. The purpose of this paper is to find out a new evaluation method of motion and MR sickness. This paper investigates a relationship between the whole-body vibration related to MR technologies and the motion aftereffect (MAE) phenomenon in the human visual system. This MR environment is modeled after advanced driver assistance systems in near-future vehicles. The seated subjects in the MR simulator were shaken in the pitch direction ranging from 0.1 to 2.0 Hz. Results show that MAE is useful for evaluation of MR sickness incidence. In addition, a method to reduce the MR sickness by auditory stimulation is proposed.

  5. Automated reading of a microtitre plate: preliminary evaluation in antimicrobial susceptibility tests and Enterobacteriaceae identification.

    PubMed Central

    Courcol, R J; Deleersnyder, H; Roussel-Delvallez, M; Martin, G R

    1983-01-01

    An automated microELISA Reader was evaluated for its ability to read and interpret microtitre plates. A total of 309 microtitre plates were investigated by automated and visual methods. There was disagreement between the methods in one hundred and twelve (0.6%) wells. However agreements between the two methods for susceptibility tests and Enterobacteriaceae identification were respectively 98.8% and 89.3%. PMID:6338058

  6. Preliminary evaluation of the gaseous effluent sampling and monitoring systems at the 291-Z-1 and 296-Z-3 stacks. Plutonium finishing facility

    SciTech Connect

    Schwendiman, L.C.; Glissmeyer, J.A.

    1992-04-01

    The 291-Z-1 and 296-Z-3 stack effluent particulate sampling and monitoring systems are being evaluated for compliance with Atlantic Richfield Hanford Company`s Interim Criteria for such systems. This evaluation is part of a study by Battelle-Northwest of gaseous effluent sampling systems in ARHCO facilities. This letter report presents a preliminary evaluation of the mentioned facilities and the indicated improvements needed to meet the Interim Criteria so that conceptual design work for improved systems can be initiated. There is currently underway a detailed study at the two stacks including a series of sampling experiments, the findings of which will not be included in this report. The gaseous effluent sampling system at the 291-Z-1 and 296-Z-3 stacks are very dissimilar and will be treated in separate sections of this report. The discussions for each sampling system will include a brief description and a preliminary evaluation of the systems.

  7. The evaluation of trace elements of interest in kidney disease in commonly consumed greenhouse vegetables in Isfahan, Iran: preliminary results

    PubMed Central

    Abdi, Mohammad Reza; Rezaee Ebrahim Saraee, Khadijeh; Rezvani Fard, Mehdi; Khorsandi, Jamshid; Baradaran-Ghahfarokhi, Milad

    2014-01-01

    Trace elements play a significant role in biological processes. The aim of this study was to evaluate the trace elements of interest in kidney disease in commonly consumed greenhouse vegetables in Isfahan, Iran. Six kinds of greenhouse vegetables namely; Raphanus sativus (Radish), Cucumis sativus (Cucamber), Solanum lycopersicum (Tomato), green Capsicum annuum (Green bell pepper), yellow Capsicum annuum (Yellow bell pepper) and red Capsicum annuum (Red bell pepper) were collected from Isfahan greenhouses, between December 2012 to March 2013. The vegetables were analyzed in order to determine the concentrations of trace elements and trace minerals using instrumental neutron activation analysis (INAA). The results of INAA showed that, the concentrations of Fe (Iron), Mn (Manganese) and Zn (Zinc) were varied from <10-50.0 mgkg-1, 6.8-15.0 mgkg-1 and 10.0-23.0 mgkg-1, respectively. The elemental concentration of Fe, Mn and Zn in all of the samples were less than the defined tolerable Upper Intake Level (UIL). The results of this study revealed that, considering the measured trace elements and mineral content levels, Isfahan greenhouse vegetables do not impose any serious health harmful effects for individuals in the studied area due to their meal consumptions. PMID:25340168

  8. The evaluation of trace elements of interest in kidney disease in commonly consumed greenhouse vegetables in Isfahan, Iran: preliminary results.

    PubMed

    Abdi, Mohammad Reza; Rezaee Ebrahim Saraee, Khadijeh; Rezvani Fard, Mehdi; Khorsandi, Jamshid; Baradaran-Ghahfarokhi, Milad

    2014-01-01

    Trace elements play a significant role in biological processes. The aim of this study was to evaluate the trace elements of interest in kidney disease in commonly consumed greenhouse vegetables in Isfahan, Iran. Six kinds of greenhouse vegetables namely; Raphanus sativus (Radish), Cucumis sativus (Cucamber), Solanum lycopersicum (Tomato), green Capsicum annuum (Green bell pepper), yellow Capsicum annuum (Yellow bell pepper) and red Capsicum annuum (Red bell pepper) were collected from Isfahan greenhouses, between December 2012 to March 2013. The vegetables were analyzed in order to determine the concentrations of trace elements and trace minerals using instrumental neutron activation analysis (INAA). The results of INAA showed that, the concentrations of Fe (Iron), Mn (Manganese) and Zn (Zinc) were varied from <10-50.0 mgkg(-1), 6.8-15.0 mgkg(-1) and 10.0-23.0 mgkg(-1), respectively. The elemental concentration of Fe, Mn and Zn in all of the samples were less than the defined tolerable Upper Intake Level (UIL). The results of this study revealed that, considering the measured trace elements and mineral content levels, Isfahan greenhouse vegetables do not impose any serious health harmful effects for individuals in the studied area due to their meal consumptions. PMID:25340168

  9. PRELIMINARY EVALUATION OF SPIROTOME® DEVICE FOR LIVER BIOPSY IN GREEN IGUANAS (IGUANA IGUANA): A PILOT STUDY.

    PubMed

    Nardini, Giordano; Origgi, Francesco C; Leopardi, Stefania; Zaghini, Anna; Saunders, Jimmy H; Vignoli, Massimo

    2016-06-01

    The aim of this study was to evaluate a large-core manual biopsy device (Spirotome(®), Medinvents, 3500 Hasselt, Belgium) for liver sampling and histologic diagnosis in green iguanas (Iguana iguana). The study included eight green iguanas, and two ultrasound-guided biopsies were collected for each lizard, for 16 biopsies in total. The procedure was carried out under general anesthesia induced by intravenous injection of propofol (10 mg/kg) maintained with a mixture of 2.0% isoflurane and 0.8-1.2 L/min oxygen after tracheal intubation. Fourteen (87.5%) of the 16 biopsies were considered diagnostic. Liver biopsy quality was assessed according to sample size and tissue preservation. In particular, mean length (16.2 ± 4.5 mm), width (2.2 ± 0.5 mm), area (34.8 ± 6.9 mm(2)), and number of portal areas (9.4 ± 3.9) of each biopsy were recorded for all green iguanas. The total available surface of the sections obtained from the biopsies and their grade of preservation enabled a satisfactory evaluation of the parenchymal architecture. One of the green iguanas in the study died the day after the procedure due to severe hemocoeloma. Risk assessment evaluation suggested that small green iguanas may not be suitable for this biopsy procedure. PMID:27468023

  10. PRELIMINARY EVALUATION OF SPIROTOME® DEVICE FOR LIVER BIOPSY IN GREEN IGUANAS (IGUANA IGUANA): A PILOT STUDY.

    PubMed

    Nardini, Giordano; Origgi, Francesco C; Leopardi, Stefania; Zaghini, Anna; Saunders, Jimmy H; Vignoli, Massimo

    2016-06-01

    The aim of this study was to evaluate a large-core manual biopsy device (Spirotome(®), Medinvents, 3500 Hasselt, Belgium) for liver sampling and histologic diagnosis in green iguanas (Iguana iguana). The study included eight green iguanas, and two ultrasound-guided biopsies were collected for each lizard, for 16 biopsies in total. The procedure was carried out under general anesthesia induced by intravenous injection of propofol (10 mg/kg) maintained with a mixture of 2.0% isoflurane and 0.8-1.2 L/min oxygen after tracheal intubation. Fourteen (87.5%) of the 16 biopsies were considered diagnostic. Liver biopsy quality was assessed according to sample size and tissue preservation. In particular, mean length (16.2 ± 4.5 mm), width (2.2 ± 0.5 mm), area (34.8 ± 6.9 mm(2)), and number of portal areas (9.4 ± 3.9) of each biopsy were recorded for all green iguanas. The total available surface of the sections obtained from the biopsies and their grade of preservation enabled a satisfactory evaluation of the parenchymal architecture. One of the green iguanas in the study died the day after the procedure due to severe hemocoeloma. Risk assessment evaluation suggested that small green iguanas may not be suitable for this biopsy procedure.

  11. Evaluating a Contribution of the Knock-on Deuterons to the Neutron Yield in the Experiments with Weakly Collisional Plasma Jets (Part 1)

    SciTech Connect

    Ryutov, D. D.

    2015-12-01

    Laser-generated interpenetrating plasma jets are widely used in the studies of collisionless interaction of counter-streaming plasmas in conjunction with possible formation of collisionless shocks. In a number of experiments of this type the plasma is formed on plastic targets made of CH or CD. The study of the DD neutron production from the interaction between two CD jets on the one hand and between a CD jet and a CH jet could serve as a qualitative indicator of the collisionless shock formation. The purpose of this memo is a discussion of the effect of collisions on the neutron generation in the interpenetrating CH and CD jets. First, the kinematics of the large-deflection collisions of the deuterons and carbon are discussed. Then the scattering angles are related with the corresponding Rutherford cross-section. After that expression for the number of the backscattered deuterons is provided, and their contribution to the neutron yield is evaluated. The results may be of some significance to the kinetic codes benchmarking and developing the neutron diagnostic.

  12. Coal liquefaction process streams characterization and evaluation: The preliminary evaluation of the kinetics of coal liquefaction distillation resid conversion

    SciTech Connect

    Klein, M.T.; Calkins, W.H.; Huang, He

    1994-02-01

    This study evaluated the use of a novel laboratory-scale batch reactor, designed by the University of Delaware, to study the kinetics of coal liquefaction resid reactivity. The short time batch reactor (STBR) is capable of conducting reactions at temperatures up to 450{degrees}C and pressures up to 2500 psi at well-defined reaction times from a few seconds to 30 min or longer. Sixty experiments were conducted with the STBR in this project. The products of the resid/tetralin/hydrogen reaction were separated by solubility, and several analytical procedures were used to evaluate the reaction products, including thermogravimetric analysis (TGA), gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Changes were monitored in the boiling ranges of the products, as a function of process conditions (time, temperature, and tetralin donor solvent-to-resid ratio), with and without catalysts. Two distillation resid samples were studied; Sample 1 is the resid of the second stage product stream from Wilsonville Run 259 which used Pittsburgh seam coal (Ireland mine) bituminous coal, and Sample 2 is the resid of the same streak from Wilsonville Run 260 which used Wyodak and Anderson (Black Thunder Mine) subbituminous coal. It was determined that the resid reactivity was different for the two samples studied. The results demonstrate that further development of this experimental method is warranted to empirically assess resid reactivity and to provide data for use in the construction of an empirical model of coal conversion in the direct liquefaction process.

  13. Preliminary evaluation of the diffraction behind the PROBA 3/ASPIICS optimized occulter

    NASA Astrophysics Data System (ADS)

    Baccani, Cristian; Landini, Federico; Romoli, Marco; Taccola, Matteo; Schweitzer, Hagen; Fineschi, Silvano; Bemporad, Alessandro; Loreggia, Davide; Capobianco, Gerardo; Pancrazzi, Maurizio; Focardi, Mauro; Noce, Vladimiro; Thizy, Cédric; Servaye, Jean-Sébastien; Renotte, Etienne

    2016-07-01

    PROBA-3 is a technological mission of the European Space Agency (ESA), devoted to the in-orbit demon- stration of formation flying (FF) techniques and technologies. ASPIICS is an externally occulted coronagraph approved by ESA as payload in the framework of the PROBA-3 mission and is currently in its C/D phase. FF offers a solution to investigate the solar corona close the solar limb using a two-component space system: the external occulter on one spacecraft and the optical instrument on the other, separated by a large distance and kept in strict alignment. ASPIICS is characterized by an inter-satellite distance of ˜144 m and an external occulter diameter of 1.42 m. The stray light due to the diffraction by the external occulter edge is always the most critical offender to a coronagraph performance: the designer work is focused on reducing the stray light and carefully evaluating the residuals. In order to match this goal, external occulters are usually characterized by an optimized shape along the optical axis. Part of the stray light evaluation process is based on the diffraction calculation with the optimized occulter and with the whole solar disk as a source. We used the field tracing software VirtualLabTM Fusion by Wyrowski Photonics [1] to simulate the diffraction. As a first approach and in order to evaluate the software, we simulated linear occulters, through as portions of the flight occulter, in order to make a direct comparison with the Phase-A measurements [2].

  14. SIFT - A preliminary evaluation. [Software Implemented Fault Tolerant computer for aircraft control

    NASA Technical Reports Server (NTRS)

    Palumbo, D. L.; Butler, R. W.

    1983-01-01

    This paper presents the results of a performance evaluation of the SIFT computer system conducted in the NASA AIRLAB facility. The essential system functions are described and compared to both earlier design proposals and subsequent design improvements. The functions supporting fault tolerance are found to consume significant computing resources. With SIFT's specimen task load, scheduled at a 30-Hz rate, the executive tasks such as reconfiguration, clock synchronization and interactive consistency, require 55 percent of the available task slots. Other system overhead (e.g., voting and scheduling) use an average of 50 percent of each remaining task slot.

  15. The Evaluation of Game-based E-learning for Medical Education: a Preliminary Survey

    PubMed Central

    Lin, Chao-Cheng; Li, Yu-Chuan; Bai, Ya-Mei; Chen, Jen-Yeu; Hsu, Chien-Yeh; Wang, Chih-Hung; Chiu, Hung-Wen; Wan, Hsu-Tien

    2005-01-01

    Game-Based e-learning (GBeL) was a newly designed platform for education of students with higher education, especially for medical students. The purpose of this study was to preliminarily evaluate the attraction of GBeL, the motivation toward GBeL and the learning effect. We found more than 80% of students thought that GBeL was attractive and more interesting than traditional class. However, the percentage of enhancing interest to learn and learning more complete and deep knowledge were less than 50%. PMID:16779319

  16. Topaz II preliminary safety assessment

    SciTech Connect

    Marshall, A.C. ); Standley, V. ); Voss, S.S. ); Haskin, E. )

    1993-01-10

    The Strategic Defense Initiative Organization (SDIO) decided to investigate the possibility of launching a Russian Topaz II space nuclear power system. A preliminary safety assessment was conducted to determine whether or not a space mission could be conducted safely and within budget constraints. As part of this assessment, a safety policy and safety functional requirements were developed to guide both the safety assessment and future Topaz II activities. A review of the Russian flight safety program was conducted and documented. Our preliminary safety assessment included a top level event tree, neutronic analysis of normal and accident configurations, an evaluation of temperature coefficients of reactivity, a reentry and disposal analysis, and analysis of postulated launch abort impact accidents, and an analysis of postulated propellant fire and explosion accidents. Based on the assessment, it appears that it will be possible to safely launch the Topaz II system in the U.S. with some possible system modifications. The principal system modifications will probably include design changes to preclude water flooded criticality and to assure intact reentry.

  17. Topaz II preliminary safety assessment

    SciTech Connect

    Marshall, A.C. ); Standley, V. ); Voss, S.S. ); Haskin, E. . Dept. of Chemical and Nuclear Engineering)

    1992-01-01

    The Strategic Defense Initiative Organization (SDIO) decided to investigate the possibility of launching a Russian Topaz 11 space nuclear power system. A preliminary safety assessment was conducted to determine whether or not a space mission could be conducted safely and within budget constraints. As part of this assessment, a safety policy and safety functional requirements were developed to guide both the safely assessment and future Topaz II activities. A review of the Russian flight safety program was conducted and documented. Our preliminary safety assessment included a top level event tree, neutronic analysis of normal and accident configurations, an evaluation of temperature coefficients of reactivity, a reentry and disposal analysis, and analysis of postulated launch abort impact accidents, and an analysis of postulated propellant fire and explosion accidents. Based on the assessment, it appears that it will be possible to safely launch the Topaz II system in the US with some possible system modifications. The principal system modifications will probably include design changes to preclude water flooded criticality and to assure intact reentry.

  18. Design, characterisation and preliminary clinical evaluation of a novel mucoadhesive topical formulation containing tetracycline for the treatment of periodontal disease.

    PubMed

    Jones, D S; Woolfson, A D; Brown, A F; Coulter, W A; McClelland, C; Irwin, C R

    2000-07-01

    This study describes the formulation, characterisation and preliminary clinical evaluation of mucoadhesive, semi-solid formulations containing hydroxyethylcellulose (HEC, 1-5%, w/w), polyvinylpyrrolidine (PVP, 2 or 3%, w/w), polycarbophil (PC, 1 or 3%, w/w) and tetracycline (5%, w/w, as the hydrochloride). Each formulation was characterised in terms of drug release, hardness, compressibility, adhesiveness (using a texture analyser in texture profile analysis mode), syringeability (using a texture analyser in compression mode) and adhesion to a mucin disc (measured as a detachment force using the texture analyser in tensile mode). The release exponent for the formulations ranged from 0.78+/-0.02 to 1. 27+/-0.07, indicating that drug release was non-diffusion controlled. Increasing the concentrations of each polymeric component significantly increased the time required for 10 and 30% release of the original mass of tetracycline, due to both increased viscosity and, additionally, the unique swelling properties of the formulations. Increasing concentrations of each polymeric component also increased the hardness, compressibility, adhesiveness, syringeability and mucoadhesion of the formulations. The effects on product hardness, compressibility and syringeability may be due to increased product viscosity and, hence, increased resistance to compression. Similarly, the effects of these polymers on adhesiveness/mucoadhesion highlight their mucoadhesive nature and, importantly, the effects of polymer state (particularly PC) on these properties. Thus, in formulations where the neutralisation of PC was maximally suppressed, adhesiveness and mucoadhesion were also maximal. Interestingly, statistical interactions were primarily observed between the effects of HEC and PC on drug release, mechanical and mucoadhesive properties. These were explained by the effects of HEC on the physical state of PC, namely swollen or unswollen. In the preliminary clinical evaluation, a formulation

  19. SU-E-T-567: Neutron Dose Equivalent Evaluation for Pencil Beam Scanning Proton Therapy with Apertures

    SciTech Connect

    Geng, C; Schuemann, J; Moteabbed, M; Paganetti, H

    2015-06-15

    Purpose: To determine the neutron contamination from the aperture in pencil beam scanning during proton therapy. Methods: A Monte Carlo based proton therapy research platform TOPAS and the UF-series hybrid pediatric phantoms were used to perform this study. First, pencil beam scanning (PBS) treatment pediatric plans with average spot size of 10 mm at iso-center were created and optimized for three patients with and without apertures. Then, the plans were imported into TOPAS. A scripting method was developed to automatically replace the patient CT with a whole body phantom positioned according to the original plan iso-center. The neutron dose equivalent was calculated using organ specific quality factors for two phantoms resembling a 4- and 14-years old patient. Results: The neutron dose equivalent generated by the apertures in PBS is 4–10% of the total neutron dose equivalent for organs near the target, while roughly 40% for organs far from the target. Compared to the neutron dose equivalent caused by PBS without aperture, the results show that the neutron dose equivalent with aperture is reduced in the organs near the target, and moderately increased for those organs located further from the target. This is due to the reduction of the proton dose around the edge of the CTV, which causes fewer neutrons generated in the patient. Conclusion: Clinically, for pediatric patients, one might consider adding an aperture to get a more conformal treatment plan if the spot size is too large. This work shows the somewhat surprising fact that adding an aperture for beam scanning for facilities with large spot sizes reduces instead of increases a potential neutron background in regions near target. Changran Geng is supported by the Chinese Scholarship Council (CSC) and the National Natural Science Foundation of China (Grant No. 11475087)

  20. Development and Psychometric Evaluation of a Socioeconomic Status Questionnaire for Urban Households (SESIran): The Preliminary Version

    PubMed Central

    Abobakri, Omid; Sadeghi-Bazargani, Homayoun; Asghari-Jafarabadi, Mohammad; Alizadeh Aghdam, Mohammad Bagher; Imani, Ali; Tabrizi, Jafarsadegh; Salarilak, Shaker; Farahbakhsh, Mostafa

    2015-01-01

    Background: The aim of present study was to develop and validate an appropriate socioeconomic status (SES) assessment questionnaire to be used through health studies in Iranian urban households. Methods: The study was conducted through a mixed method study design in Tabriz, northwest of Iran in 2014. It was conducted in several stages including: development of initial version, qualitative study, feasibility evaluation, and assessment of the validity as well as the reliability. The internal consistency, test-retest reliability, content validity, concurrent validity and construct validity were assessed. Results: With respect to the assessment of construct validity, 5 domains (factors) were extracted includ­ing: main factor (α=0.84), self-evaluation of expenditure capacity (α=0.96), wealth (α=0.70), home and furniture (α=0.66) and costs related to health (α=0.55). Intraclass correlation coefficient was above 0.6 for all factors except for wealth domain. Conclusion: The questionnaire developed appeared to be a valid and reliable SES assessment tool. It may be of value to be used not only as a complementary questionnaire in most health surveys or clini­cal studies, but also as a main questionnaire in health equity and health economics research. PMID:26933644

  1. Target population involvement in urban ciclovias: a preliminary evaluation of St. Louis open streets.

    PubMed

    Hipp, J Aaron; Eyler, Amy A; Kuhlberg, Jill A

    2013-12-01

    Ciclovias are active street events when roads are open to walkers, cyclists, and families and closed to automobiles. Over 70 cities in the USA have implemented ciclovias to promote physical activity. The authors evaluated four events during 2010 to determine what activities participants perform and who is attending. For two ciclovia events in St. Louis, Missouri, observation reports of activities, gender, and age of 1,452 participants were collected, and 82 adults were interviewed via direct approach. The survey covered six domains: physical activity, travel to event, sense of community, marketing, economic impact, and demographics. Each event occurred within the city, along multiple streets. Domains were selected from Ciclovia Recreativa developed by Ciclovia Bogota, Pan American Health Organization, and CDC. Additional questions addressed city-specific goals and matched similar evaluations in other cities. Over 50 % of participants met CDC-defined weekly minute thresholds for physical activity. Participants, primarily (>80 %) middle class, college educated, and white, were not representative of the majority minority city population, which has high rates of poverty, and low percentage of college graduates. Cities must work with residents to increase low-income minority population participation in ciclovia-based physical activity. PMID:22948790

  2. Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

    PubMed Central

    Łukasiewicz, Adam; Garkowski, Adam; Rutka, Katarzyna; Janica, Jacek; Łebkowska, Urszula

    2016-01-01

    It is hypothesized that the degree of vascularization of the thrombus may have a significant impact on the rupture of aortic aneurysms. The presence of neovascularization of the vessel wall and mural thrombus has been confirmed only in histopathological studies. However, no non-invasive imaging technique of qualitative assessment of thrombus and neovascularization has been implemented so far. Contrast-enhanced ultrasound (CEUS) has been proposed as a feasible and minimally invasive technique for in vivo visualization of neovascularization in the evaluation of tumors and atherosclerotic plaques. The aim of this study was the evaluation of mural thrombus and AAAs wall with CEUS. CEUS was performed in a group of seventeen patients with AAAs. The mural thrombus enhancement was recognized in 12 cases, yet no significant correlation between the degree of contrast enhancement and AAAs diameter, thrombus width, and thrombus echogenicity was found. We observed a rise in AAAs thrombus heterogeneity with the increase in the aneurysm diameter (r = 0.62, p = 0.017). In conclusion CEUS can visualize small channels within AAAs thrombus, which could be a result of an ongoing angiogenesis. There is a need for further research to find out whether the degree of vascularization of the thrombus may have a significant impact on the rupture of aneurysms. PMID:27677245

  3. Target population involvement in urban ciclovias: a preliminary evaluation of St. Louis open streets.

    PubMed

    Hipp, J Aaron; Eyler, Amy A; Kuhlberg, Jill A

    2013-12-01

    Ciclovias are active street events when roads are open to walkers, cyclists, and families and closed to automobiles. Over 70 cities in the USA have implemented ciclovias to promote physical activity. The authors evaluated four events during 2010 to determine what activities participants perform and who is attending. For two ciclovia events in St. Louis, Missouri, observation reports of activities, gender, and age of 1,452 participants were collected, and 82 adults were interviewed via direct approach. The survey covered six domains: physical activity, travel to event, sense of community, marketing, economic impact, and demographics. Each event occurred within the city, along multiple streets. Domains were selected from Ciclovia Recreativa developed by Ciclovia Bogota, Pan American Health Organization, and CDC. Additional questions addressed city-specific goals and matched similar evaluations in other cities. Over 50 % of participants met CDC-defined weekly minute thresholds for physical activity. Participants, primarily (>80 %) middle class, college educated, and white, were not representative of the majority minority city population, which has high rates of poverty, and low percentage of college graduates. Cities must work with residents to increase low-income minority population participation in ciclovia-based physical activity.

  4. Preliminary technical and legal evaluation of disposing of nonhazardous oil field waste into salt caverns

    SciTech Connect

    Veil, J.; Elcock, D.; Raivel, M.; Caudle, D.; Ayers, R.C. Jr.; Grunewald, B.

    1996-06-01

    Caverns can be readily formed in salt formations through solution mining. The caverns may be formed incidentally, as a result of salt recovery, or intentionally to create an underground chamber that can be used for storing hydrocarbon products or compressed air or disposing of wastes. The purpose of this report is to evaluate the feasibility, suitability, and legality of disposing of nonhazardous oil and gas exploration, development, and production wastes (hereafter referred to as oil field wastes, unless otherwise noted) in salt caverns. Chapter 2 provides background information on: types and locations of US subsurface salt deposits; basic solution mining techniques used to create caverns; and ways in which salt caverns are used. Later chapters provide discussion of: federal and state regulatory requirements concerning disposal of oil field waste, including which wastes are considered eligible for cavern disposal; waste streams that are considered to be oil field waste; and an evaluation of technical issues concerning the suitability of using salt caverns for disposing of oil field waste. Separate chapters present: types of oil field wastes suitable for cavern disposal; cavern design and location; disposal operations; and closure and remediation. This report does not suggest specific numerical limits for such factors or variables as distance to neighboring activities, depths for casings, pressure testing, or size and shape of cavern. The intent is to raise issues and general approaches that will contribute to the growing body of information on this subject.

  5. Development and preliminary evaluation of a pediatric Spanish/English speech perception task

    PubMed Central

    Calandruccio, Lauren; Gomez, Bianca; Buss, Emily; Leibold, Lori J.

    2014-01-01

    Purpose To develop a task to evaluate children’s English and Spanish speech perception abilities in either noise or competing speech maskers. Methods Eight bilingual Spanish/English and eight age matched monolingual English children (ages 4.9 –16.4 years) were tested. A forced-choice, picture-pointing paradigm was selected for adaptively estimating masked speech reception thresholds. Speech stimuli were spoken by simultaneous bilingual Spanish/English talkers. The target stimuli were thirty disyllabic English and Spanish words, familiar to five-year-olds, and easily illustrated. Competing stimuli included either two-talker English or two-talker Spanish speech (corresponding to target language) and spectrally matched noise. Results For both groups of children, regardless of test language, performance was significantly worse for the two-talker than the noise masker. No difference in performance was found between bilingual and monolingual children. Bilingual children performed significantly better in English than in Spanish in competing speech. For all listening conditions, performance improved with increasing age. Conclusions Results indicate that the stimuli and task are appropriate for speech recognition testing in both languages, providing a more conventional measure of speech-in-noise perception as well as a measure of complex listening. Further research is needed to determine performance for Spanish-dominant listeners and to evaluate the feasibility of implementation into routine clinical use. PMID:24686915

  6. New bifunctional antioxidant/σ1 agonist ligands: Preliminary chemico-physical and biological evaluation.

    PubMed

    Arena, Emanuela; Cacciatore, Ivana; Cerasa, Laura S; Turkez, Hasan; Pittalà, Valeria; Pasquinucci, Lorella; Marrazzo, Agostino; Parenti, Carmela; Di Stefano, Antonio; Prezzavento, Orazio

    2016-07-15

    We previously reported bifunctional sigma-1 (σ1) ligands endowed with antioxidant activity (1 and 2). In the present paper, pure enantiomers (R)-1 and (R)-2 along with the corresponding p-methoxy (6, 11), p-fluoro derivatives (7, 12) were synthesized. σ1 and σ2 affinities, antioxidant properties, and chemico-physical profiles were evaluated. Para derivatives, while maintaining strong σ1 affinity, displayed improved σ1 selectivity compared to the parent compounds 1 and 2. In vivo evaluation of compounds 1, 2, (R)-1, 7, and 12 showed σ1 agonist pharmacological profile. Chemico-physical studies revealed that amides 2, 11 and 12 were more stable than corresponding esters 1, 6 and 7 under our experimental conditions. Antioxidant properties were exhibited by fluoro derivatives 7 and 12 being able to increase total antioxidant capacity (TAC). Our results underline that p-substituents have an important role on σ1 selectivity, TAC, chemical and enzymatic stabilities. In particular, our data suggest that new very selective compounds 7 and 12 could be promising tools to investigate the disorders in which σ1 receptor dysfunction and oxidative stress are contemporarily involved. PMID:27262426

  7. Preliminary Evaluation of Convective Heat Transfer in a Water Shield for a Surface Power Reactor

    NASA Technical Reports Server (NTRS)

    Pearson J. Boise; Reid, Robert S.

    2007-01-01

    As part of the Vision for Space Exploration, the end of the next decade will bring man back to the surface of the moon. A crucial issue for the establishment of human presence on the moon will be the availability of compact power sources. This presence could require greater than 10's of kWt's in follow on years. Nuclear reactors are well suited to meet the needs for power generation on the lunar or Martian surface. Radiation shielding is a key component of any surface power reactor system. Several competing concepts exist for lightweight, safe, robust shielding systems such as a water shield, lithium hydride (LiH), and boron carbide. Water offers several potential advantages, including reduced cost, reduced technical risk, and reduced mass. Water has not typically been considered for space reactor applications because of the need for gravity to fix the location of any vapor that could form radiation streaming paths. The water shield concept relies on the predictions of passive circulation of the shield water by natural convection to adequately cool the shield. This prediction needs to be experimentally evaluated, especially for shields with complex geometries. NASA Marshall Space Flight Center has developed the experience and facilities necessary to do this evaluation in its Early Flight Fission - Test Facility (EFF-TF).

  8. Evaluation of the thrombus of abdominal aortic aneurysms using contrast enhanced ultrasound - preliminary results

    NASA Astrophysics Data System (ADS)

    Łukasiewicz, Adam; Garkowski, Adam; Rutka, Katarzyna; Janica, Jacek; Łebkowska, Urszula

    2016-09-01

    It is hypothesized that the degree of vascularization of the thrombus may have a significant impact on the rupture of aortic aneurysms. The presence of neovascularization of the vessel wall and mural thrombus has been confirmed only in histopathological studies. However, no non-invasive imaging technique of qualitative assessment of thrombus and neovascularization has been implemented so far. Contrast-enhanced ultrasound (CEUS) has been proposed as a feasible and minimally invasive technique for in vivo visualization of neovascularization in the evaluation of tumors and atherosclerotic plaques. The aim of this study was the evaluation of mural thrombus and AAAs wall with CEUS. CEUS was performed in a group of seventeen patients with AAAs. The mural thrombus enhancement was recognized in 12 cases, yet no significant correlation between the degree of contrast enhancement and AAAs diameter, thrombus width, and thrombus echogenicity was found. We observed a rise in AAAs thrombus heterogeneity with the increase in the aneurysm diameter (r = 0.62, p = 0.017). In conclusion CEUS can visualize small channels within AAAs thrombus, which could be a result of an ongoing angiogenesis. There is a need for further research to find out whether the degree of vascularization of the thrombus may have a significant impact on the rupture of aneurysms.

  9. Risk assessments for energy systems and role of preliminary degree-of-hazard evaluations

    SciTech Connect

    Habegger, L.J.; Fingleton, D.J.

    1985-11-01

    The appropriate approach to risk or hazard assessment can vary considerably, depending on various factors, including the intended application of the results and the time other resources available to conduct the assessment. This paper illustrates three types of interrelated assessments. Although they can be mutually supportive, they have fundamentally different objectives, which require major differences in approach. The example of the overall risk assessment of alternative major energy technologies illustrates the compilation of a wide range of available risk data applicable to these systems. However, major uncertainties exist in the assessments, and public perception of their importance could play an important role in final system evaluations. A more narrowly defined risk assessment, often focusing on an individual component of a larger system, is the most commonly used approach in regulatory applications. The narrow scope allows in-depth analysis of risks and associated uncertainties, but it may also contribute to a loss of perspective on the magnitude of the assessed risk relative to that of the unassessed risks. In some applications, it is useful to conduct semiquantitative degree-of-hazard evaluations as a means of setting priorities for detailed risk assessment. The MAHAS procedure described in this paper provides a means of rapidly ranking relative hazards from various sources using easily accessible data. However, these rankings should not be used as definitive input for selecting technology alternatives or developing regulations. 25 refs., 6 tabs.

  10. Evaluation of the Doppler-Broadening of Gamma-Ray Spectra from Neutron Inelastic Scattering on Light Nuclei

    SciTech Connect

    Womble, Phillip C.; Barzilov, Alexander; Novikov, Ivan; Howard, Joseph; Musser, Jason

    2009-03-10

    Neutron-induced gamma-ray reactions are extensively used in the nondestructive analysis of materials and other areas where the information about the chemical composition of a substance is crucial. The common technique to find the intensity of the gamma ray is to fit gamma-ray line shape with an analytical function, for example, a Gaussian. However, the Gaussian fitting may fail if the gamma-ray peak is Doppler-broadened since this leads to the miscalculation of the area of the peak and, therefore, to misidentification of the material. Due to momentum considerations, Doppler-broadening occurs primarily with gamma rays from neutron-induced inelastic scattering reactions with light nuclei. The recoiling nucleus of interest must have excited states whose lifetimes are much smaller than the time of flight in the material. We have examined various light nuclei bombarded by 14 MeV neutrons to predict when the peak shape of a neutron-induced gamma ray emitted from these nuclei will be Doppler-broadened. We have found that nearly all the gamma rays from neutron-induced gamma-ray reactions on light elements (A<20) are Doppler-broadened with only a few exceptions. This means that utilization of resolution curves derived from isotopic sources or thermal neutron capture reactions have little value in the analysis.

  11. Atmospheric neutrons

    NASA Technical Reports Server (NTRS)

    Korff, S. A.; Mendell, R. B.; Merker, M.; Light, E. S.; Verschell, H. J.; Sandie, W. S.

    1979-01-01

    Contributions to fast neutron measurements in the atmosphere are outlined. The results of a calculation to determine the production, distribution and final disappearance of atmospheric neutrons over the entire spectrum are presented. An attempt is made to answer questions that relate to processes such as neutron escape from the atmosphere and C-14 production. In addition, since variations of secondary neutrons can be related to variations in the primary radiation, comment on the modulation of both radiation components is made.

  12. Preliminary evaluation of probiotic potential of Lactobacillus plantarum strains isolated from Italian food products.

    PubMed

    Turchi, Barbara; Mancini, Simone; Fratini, Filippo; Pedonese, Francesca; Nuvoloni, Roberta; Bertelloni, Fabrizio; Ebani, Valentina Virginia; Cerri, Domenico

    2013-10-01

    The aim of this study was to investigate some probiotic properties of 42 wild Lactobacillus plantarum strains isolated from different Italian foods of animal origin. The strains were first screened for their antibiotic resistance profile (chloramphenicol, erythromycin, gentamicin, and tetracycline), subsequently they were tested for their in vitro resistance to lysozyme (100 mg L⁻¹), low pH (3.0, 2.5 and 2.0) and bile salts (0.3, 0.5 and 1.0 %). Moreover, agglutination property was studied (adhesion to Saccharomyces cerevisiae cells), as well as the presence of bsh and msa genes. The strains with the best characteristics were subjected to a further trial in order to evaluate their ability to survive to multiple stresses over time (lysozyme, low pH and bile salts) and the effect of these treatments on adhesion to yeast cells. All the strains were susceptible to chloramphenicol, erythromycin and gentamicin, while 6 strains were excluded from further evaluation because of their resistant phenotype against tetracycline. All the strains were able to grow in presence of lysozyme, as well as in MRS broth at pH 3.0. Only 4 strains showed a growth rate lower than 80 % when grown in MRS broth at pH 2.5, while a relevant growth rate decrease was observed after exposure to pH 2.0. Bile salts didn't affect the viability of the L. plantarum cells. Twenty-one strains out of 33 tested strains were able to adhere to S. cerevisiae cells. Presence of both bsh and msa genes was detected in 6 strains. The strains resistant to all the stresses, positive to agglutination with S. cerevisiae and showing bsh and msa genes were selected for further evaluation and subjected to different stress treatments over time. The assessment of growth rates showed that exposure to lysozyme significantly increased low pH resistance in L. plantarum. This increase ranged from 2.35 to 15.57 %. The consequential lysozyme and low pH exposures didn't affect the growth rate values after bile salts treatment

  13. Development and Preliminary Evaluation of TFIB, a New Bimodal Prosthetic Group for Bioactive Molecule Labeling

    PubMed Central

    2014-01-01

    The new readily available prosthetic group, tetrafluorophenyl 4-fluoro-3-iodobenzoate (TFIB), designed for both molecular imaging and targeted radionuclide therapy purposes was radiolabeled either with fluorine or iodine radionuclides with excellent radiochemical yields and purities. These radiolabeled tags were conjugated to N,N-diethylethylenediamine to give melanin-targeting radiotracers [125I]9 and [18F]9, which were successfully evaluated by PET and gamma scintigraphic imaging in B16F0 pigmented melanoma-bearing C57BL/6J mice. Then, radiolabeled [125I]/[18F]TFIB was used to tag tumor-targeting peptides (i.e., PEG3[c(RGDyK)]2 and NDP-MSH targeting αvβ3 integrin and MC1R receptors, respectively) in mild conditions and with good radiochemical yields (47–83% d.c.) and purities (>99%). The resulting radiolabeled peptides were assessed both in vitro and by PET imaging in animal models. PMID:25699145

  14. Modular synthesis and preliminary biological evaluation of stereochemically diverse 1,3-dioxanes.

    PubMed

    Wong, Jason C; Sternson, Scott M; Louca, Joseph B; Hong, Roger; Schreiber, Stuart L

    2004-09-01

    Modular synthesis and substrate stereocontrol were combined to furnish 18,000 diverse 1,3-dioxanes whose distribution in chemical space rivals that of a reference set of over 2,000 bioactive small molecules. Library quality was assessed at key synthetic stages, culminating in a detailed postsynthesis analysis of purity, yield, and structural characterizability, and the resynthesis of library subsets that did not meet quality standards. The importance of this analysis-resynthesis process is highlighted by the discovery of new biological probes through organismal and protein binding assays, and by determination of the building block and stereochemical basis for their bioactivity. This evaluation of a portion of the 1,3-dioxane library suggests that many additional probes for chemical genetics will be identified as the entire library becomes biologically annotated. PMID:15380188

  15. Preliminary evaluation of radiation control coatings for energy conservation in buildings

    SciTech Connect

    Anderson, R.W.

    1992-02-01

    Radiation Control Coatings (RCCs) applied to external building surfaces can reflect about 85 percent of the solar heating from the surfaces of buildings. Since in warm climates, solar heating is the primary source of heat gain through walls and roofs, RCC technology represents an alternative or adjunct to conventional thermal control methods (e.g., thermal insulation) for opaque building components. The primary objectives of this project were to: (1) obtain solar and infrared reflectance data for representative RCC products, (2) evaluate test methods for measurement of the radiative properties of RCCs, (3) calculate the changes in heat flow attributed to RCCs in flat roof applications in several geographic locations, and (4) compare field tests and calculated thermal performance of an RCC in a flat roof configuration. Data are presented for the radiative properties of five commercially available RCC products as determined by several test methods. The potential energy benefits of RCCs are presented for flat roofs in both warm and cold climates.

  16. Emergency medical services capacities in the developing world: preliminary evaluation and training in Addis Ababa, Ethiopia.

    PubMed

    Pozner, Charles N; Bayleygne, Tesfaye M; Davis, Mark A; Benin-Goren, Odeda; Noble, Vicki E; Halpern, Pinchas

    2003-01-01

    In December 1999, a group of emergency physicians from the United States, Israel, and Ethiopia met for the Second Annual Symposium on Emergency Medicine and to perform an initial evaluation of the prehospital care system in Addis Ababa. The symposium was structured into a workshop on prehospital care and a clinical seminar for emergency medicine providers. This article describes the current prehospital infrastructure in Addis Ababa, Ethiopia. This serves as the basis for more specific needs assessments and training interventions, which are ongoing. The authors present a list of priorities for the development of an emergency medical services (EMS) system for Addis Ababa that was generated in partnership with local government and the World Health Organization. The article contrasts these initial recommendations with those found in the literature on the development of EMS systems in developing nations.

  17. The Preliminary Evaluation of Liquid Lubricants for Space Applications by Vacuum Tribometry

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Pepper, S. V.; Herrera-Fierro, P.; Feuchter, D.; Toddy, T. J.; Jayne, D. T.; Wheeler, D. R.; Abel, P. B.; Kingsbury, E.; Morales, W.

    1994-01-01

    Four different vacuum tribometers for the evaluation of liquid lubricants for space applications are described. These range from simple ball-on-flat sliders with maximum in-situ control and surface characterization to an instrument bearing apparatus having no in-situ characterization. Thus, the former provides an abundance of surface chemical information but is not particularly simulative of most triboelements. On the other hand, the instrument bearing apparatus is completely simulative, but only allows post-mortem surface chemical information. Two other devices, a four-ball apparatus and a ball-on-plate tribometer, provide varying degrees of surface chemical information and tribo-simulation. Examples of data from each device are presented.

  18. A preliminary evaluation of an F100 engine parameter estimation process using flight data

    NASA Technical Reports Server (NTRS)

    Maine, Trindel A.; Gilyard, Glenn B.; Lambert, Heather H.

    1990-01-01

    The parameter estimation algorithm developed for the F100 engine is described. The algorithm is a two-step process. The first step consists of a Kalman filter estimation of five deterioration parameters, which model the off-nominal behavior of the engine during flight. The second step is based on a simplified steady-state model of the compact engine model (CEM). In this step, the control vector in the CEM is augmented by the deterioration parameters estimated in the first step. The results of an evaluation made using flight data from the F-15 aircraft are presented, indicating that the algorithm can provide reasonable estimates of engine variables for an advanced propulsion control law development.

  19. A preliminary evaluation of an F100 engine parameter estimation process using flight data

    NASA Technical Reports Server (NTRS)

    Maine, Trindel A.; Gilyard, Glenn B.; Lambert, Heather H.

    1990-01-01

    The parameter estimation algorithm developed for the F100 engine is described. The algorithm is a two-step process. The first step consists of a Kalman filter estimation of five deterioration parameters, which model the off-nominal behavior of the engine during flight. The second step is based on a simplified steady-state model of the 'compact engine model' (CEM). In this step the control vector in the CEM is augmented by the deterioration parameters estimated in the first step. The results of an evaluation made using flight data from the F-15 aircraft are presented, indicating that the algorithm can provide reasonable estimates of engine variables for an advanced propulsion-control-law development.

  20. Tuberous legumes: preliminary evaluation of tropical Australian and introduced species as fuel crops

    SciTech Connect

    Saxon, E.C.

    1981-04-01

    The evaluation of native and introduced legumes with starch-storing roots or tubers was undertaken to test whether plants traditionally collected as food by Australian aborigines might have a role in the development of crops for liquid fuel production (by fermentation of carbohydrates to ethanol). Tuberous-rooted legumes from overseas were planted at the Commonwealth Scientific and Industrial Research Organization, division of Tropical Crops and Pastures, Kimberley Research Station, Western Australia (15/sup 0/39'S, 128/sup 0/42'E) in December 1974, March 1978 and February 1979. Roots from the latter plantings were harvested in June 1979. Native plant material was collected during visits to aboriginal communities in the Kimberleys between April and June 1979. The native and introduced specimens were analyzed for fermentable carbohydrate and protein content. Several native plants appear more promising than introduced species as liquid fuel crops.