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Sample records for nuclear track microfilters

  1. Solid state nuclear track detection

    SciTech Connect

    Durrani, S.A.; Bull, R.K.

    1987-01-01

    This book is a basic work on the technique variously known as 'nuclear track analysis', 'track-etch technique', or 'solid state nuclear tract detection'. This has greatly expanded in range, scope and depth since the early 1960's, soon after its discovery, until there is hardly a field now in which it has not found an actual or potential use. Such applications range from archaeology, geology, space physics, medicine and biology to reactor physics and nuclear physics-to name but a few.

  2. Some observations on blood microfilters.

    PubMed Central

    Buley, R.; Lumley, J.

    1975-01-01

    Under laboratory conditions 3 types of filter designed to prevent the passage of microemboli into the circulation during the transfusion of stored blood were compared with the standard Baxter BR10 filter, designed only to hold back macroemboli, in respect of resistance to blood flow and damage to the cellular elements of the blood. In both respects the Pall Ultipor microfilter proved more efficient than the Swank IL200 microfilter and the Bentley Polyfilter (PF-127) and, except with 3-week-old blood, was comparable to the Baxter filter. PMID:1200574

  3. Nanoscale measurements of proton tracks using fluorescent nuclear track detectors

    SciTech Connect

    Sawakuchi, Gabriel O. Sahoo, Narayan; Ferreira, Felisberto A.; McFadden, Conor H.; Hallacy, Timothy M.; Granville, Dal A.; Akselrod, Mark S.

    2016-05-15

    Purpose: The authors describe a method in which fluorescence nuclear track detectors (FNTDs), novel track detectors with nanoscale spatial resolution, are used to determine the linear energy transfer (LET) of individual proton tracks from proton therapy beams by allowing visualization and 3D reconstruction of such tracks. Methods: FNTDs were exposed to proton therapy beams with nominal energies ranging from 100 to 250 MeV. Proton track images were then recorded by confocal microscopy of the FNTDs. Proton tracks in the FNTD images were fit by using a Gaussian function to extract fluorescence amplitudes. Histograms of fluorescence amplitudes were then compared with LET spectra. Results: The authors successfully used FNTDs to register individual proton tracks from high-energy proton therapy beams, allowing reconstruction of 3D images of proton tracks along with delta rays. The track amplitudes from FNTDs could be used to parameterize LET spectra, allowing the LET of individual proton tracks from therapeutic proton beams to be determined. Conclusions: FNTDs can be used to directly visualize proton tracks and their delta rays at the nanoscale level. Because the track intensities in the FNTDs correlate with LET, they could be used further to measure LET of individual proton tracks. This method may be useful for measuring nanoscale radiation quantities and for measuring the LET of individual proton tracks in radiation biology experiments.

  4. Discovery of nuclear tracks in interplanetary dust

    NASA Technical Reports Server (NTRS)

    Bradley, J. P.; Brownlee, D. E.; Fraundorf, P.

    1984-01-01

    Nuclear tracks have been identified in interplanetary dust particles (IDP's) collected from the stratosphere. The presence of tracks unambiguously confirms the extraterrestrial nature of IDP's, and the high track densities (10 to the 10th to 10 to the 11th per square centimeter) suggest an exposure age of approximately 10,000 years within the inner solar system. Tracks also provide an upper temperature limit for the heating of IDP's during atmospheric entry, thereby making it possible to distinguish between pristine and thermally modified micrometeorites.

  5. Discovery of nuclear tracks in interplanetary dust

    NASA Technical Reports Server (NTRS)

    Bradley, J. P.; Brownlee, D. E.; Fraundorf, P.

    1984-01-01

    Nuclear tracks have been identified in interplanetary dust particles (IDP's) collected from the stratosphere. The presence of tracks unambiguously confirms the extraterrestrial nature of IDP's, and the high track densities (10 to the 10th to 10 to the 11th per square centimeter) suggest an exposure age of approximately 10,000 years within the inner solar system. Tracks also provide an upper temperature limit for the heating of IDP's during atmospheric entry, thereby making it possible to distinguish between pristine and thermally modified micrometeorites.

  6. TACTIC - Ion tracking in nuclear physics

    NASA Astrophysics Data System (ADS)

    Martin, L.; Ruprecht, G.; Hager, U.; Buchmann, L.; Amaudruz, P. A.; Fox, S.; Laird, A. M.; Chipps, K.; Machule, P.; Openshaw, R.; Walden, P.; Walter, M.; Bruskiewich, P.; Shotter, A. C.

    2010-01-01

    Ion tracking is still an unusual detection method in nuclear physics. TACTIC (TRIUMF annular chamber for tracking and identification of charged particles) is suitable for tracking low-energy ejectiles. The cylindrical design allows for an electrical separation of target and drift region without hindering the ejectiles to enter the drift region. The first experiment with radioactive beam - the reaction 8Li(α,n)11B which is important for the α-process in neutrino-driven supernova winds - took place in June '09. Since no off-the-shelf analysis tools and methods are available for this kind of tracking, TRIUMF's TACTIC group developed graphical tool for analysing data that can also be used for other modern nuclear physics detectors.

  7. Nuclear track-based biosensing: an overview

    NASA Astrophysics Data System (ADS)

    Fink, Dietmar; Muñoz Hernández, Gerardo; García Arellano, Humberto; Vacík, Jiri; Havranek, Vladimir; Hnatowicz, Vladimir; Kiv, Arik; Alfonta, Lital

    2016-02-01

    An overview on the development of biosensors based on nuclear tracks in solids is presented. A few decades ago it was found that nuclear tracks in solids can be usefully applied for the creation of biosensors. Meanwhile quite a number of different strategies have emerged to fulfill this task which are summarized here. We ourselves have especially concentrated on the 'Product Enrichment Strategy', where the enrichment of products of a given analyte by a suitable biochemical reaction within the narrow confinement of etched ion tracks is used to amplify the product's signal for high-sensitivity biosensing. We also report on the application of nuclear analysis techniques for obtaining a deeper insight into these sensor structures, for the sake of their further optimization. Last not least we also discuss competing nanopore-based biosensing approaches.

  8. Nuclear track study of Jilin chondrite

    NASA Astrophysics Data System (ADS)

    Pellas, P.; Bourot-Denise, M.

    1985-02-01

    Attention is given to nuclear track records in olivines from 21 specimens of Jilin which sample the whole spectrum of Ne-21 concentrations and come from both the main mass and the strewn fragments. Although 19 of the specimens exhibit extremely low track densities, two which have high Ne-21 contents and the largest Ar-40 and He-4 losses are found, and noted to have track densities of about 750 and 1500/sq cm. These tracks are attributed to very heavy cosmic ray nuclei. These results may be explained in terms of production during the first stage exposure, or during the second irradiation stage of 0.4 Myr. The ubiquitous presence of a track density background in most samples is best explained by the spontaneous fission of U-238 since 4.0 Gyr.

  9. WIMP tracking with cryogenic nuclear emulsion

    NASA Astrophysics Data System (ADS)

    Kimura, M.; Naka, T.; Furuya, S.; Asada, T.; Katsuragawa, T.; Yoshimoto, M.; Umemoto, A.; Machii, S.; Ichiki, H.; Sato, O.; Hoshino, Y.

    2017-02-01

    Directional dark matter search experiments enable us to reveal the presence of Weakly Interacting Massive Particles. A promising detector for a directional measurement is a fine-grained nuclear emulsion consisting of fine crystals of silver bromide with 20 nm or 40 nm size. A critical task for the success of the experiment is to remove background tracks of electrons coming from stopping beta rays of 14C decays in the nuclear emulsion. An electron rejection power of at least 10-10 is needed in order to start a 10 kg experiment. We present a novel cryogenic approach to reject the electron background that makes use of the phonon effect in nuclear emulsion. For the proof of principle, we have been investigating the sensitivity of fine-grained nuclear emulsions as a function of temperature by exposing to gamma rays and ion beams with an ion implant system in the range of 77-300 K. Results of gamma ray exposure indicate that the electron rejection power is estimated to be better than 3 ×10-9 at 77 K. Results of ion exposure imply that fine-grained nuclear emulsion is sensitive to ions which are light and heavy and ion tracks' angle can be measured.

  10. Fast Track'' nuclear thermal propulsion concept

    SciTech Connect

    Johnson, R.A.; Zweig, H.R. ); Cooper, M.H.; Wett, J. Jr. )

    1993-01-10

    The objective of the Space Exploration Initiative ( America at the Threshold...,'' 1991) is the exploration of Mars by man in the second decade of the 21st century. The NASA Fast Track'' approach (NASA-LeRC Presentation, 1992) could accelerate the manned exploration of Mars to 2007. NERVA-derived nuclear propulsion represents a viable near-term technology approach to accomplish the accelerated schedule. Key milestones in the progression to the manned Mars mission are (1) demonstration of TRL-6 for the man-rateable system by 1999, (2) a robotic lunar mission by 2000, (3) the first cargo mission to Mars by 2005, and (4) the piloted Mars mission in 2007. The Rocketdyne-Westinghouse concept for nuclear thermal propulsion to achieve these milestones combines the nuclear reactor technology of the Rover/NERVA programs and the state-of-the-art hardware designs from hydrogen-fueled rocket engine successes like the Space Shuttle Main Engine (SSME).

  11. Muon Tracking to Detect Special Nuclear Materials

    SciTech Connect

    Schwellenbach, D.; Dreesen, W.; Green, J. A.; Tibbitts, A.; Schotik, G.; Borozdin, K.; Bacon, J.; Midera, H.; Milner, C.; Morris, C.; Perry, J.; Barrett, S.; Perry, K.; Scott, A.; Wright, C.; Aberle, D.

    2013-03-18

    Previous experiments have proven that nuclear assemblies can be imaged and identified inside of shipping containers using vertical trajectory cosmic-ray muons with two-sided imaging. These experiments have further demonstrated that nuclear assemblies can be identified by detecting fission products in coincidence with tracked muons. By developing these technologies, advanced sensors can be designed for a variety of warhead monitoring and detection applications. The focus of this project is to develop tomographic-mode imaging using near-horizontal trajectory muons in conjunction with secondary particle detectors. This will allow imaging in-situ without the need to relocate the objects and will enable differentiation of special nuclear material (SNM) from other high-Z materials.

  12. ``Fast Track'' nuclear thermal propulsion concept

    NASA Astrophysics Data System (ADS)

    Johnson, Richard A.; Zweig, Herbert R.; Cooper, Martin H.; Wett, Jack

    1993-01-01

    The objective of the Space Exploration Initiative (``America at the Threshold...,'' 1991) is the exploration of Mars by man in the second decade of the 21st century. The NASA ``Fast Track'' approach (NASA-LeRC Presentation, 1992) could accelerate the manned exploration of Mars to 2007. NERVA-derived nuclear propulsion represents a viable near-term technology approach to accomplish the accelerated schedule. Key milestones in the progression to the manned Mars mission are (1) demonstration of TRL-6 for the man-rateable system by 1999, (2) a robotic lunar mission by 2000, (3) the first cargo mission to Mars by 2005, and (4) the piloted Mars mission in 2007. The Rocketdyne-Westinghouse concept for nuclear thermal propulsion to achieve these milestones combines the nuclear reactor technology of the Rover/NERVA programs and the state-of-the-art hardware designs from hydrogen-fueled rocket engine successes like the Space Shuttle Main Engine (SSME).

  13. Application of Nuclear Material Tracking System to nuclear materials control

    SciTech Connect

    Eggers, R.F.

    1989-11-01

    This paper briefly reviews the design concept of the Nuclear Material Tracking System, which is called NTRAK. Subsequently, it provides preliminary estimates of NTRAK detection capability for selected situations and outlines how NTRAK can be used to defend against the insider adversary attempting to steal special nuclear material (SNM). The NTRAK is a special assembly of gamma radiation detectors. The feature of NTRAK which makes it unique is its ability to direction-find and triangulate the position of localized sources of gamma radiation. This capability allows the nuclear safeguards system designer to develop material control procedures based on the position or motion of detected material. This capability was not previously available, because detection systems were unable to determine the direction from the detectors to the nuclear material being monitored. Other features of NTRAK that make it useful for nuclear material control include its abilities to (1) detect SNM at significant ranges from the detectors, (2) verify material quantity, (3) detect theft material traveling piggyback on authorized material, and (4) provide defense in depth against the adversary insider attempting to steal SNM.

  14. Recent applications of nuclear track emulsion technique

    SciTech Connect

    Zarubin, P. I.

    2016-12-15

    A survey of recent results obtained using the nuclear track emulsion (NTE) technique in low energy applications is given. NTE irradiation with 60 MeV {sup 8}He nuclei provides identification of their decays at stopping, evaluation of the possibility of α range spectrometry, and observation of drift of thermalized {sup 8}He atoms. Correlations of α particles studied in {sup 12}C → 3α splitting induced by 14.1 MeV neutrons indicate the presence of a superposition of 0{sup +} and 2{sup +} states of the {sup 8}Be nucleus in the ground state of {sup 12}C. Angular correlations of fragments are studied in boron-enriched NTE, and the prospects of NTE application in radioactivity and nuclear fission research are discussed. It is proposed to use an automated microscope to search for collinear tripartition of heavy nuclei implanted in NTE. Surface irradiation of NTE by a {sup 252}Cf source is started. Planar events containing fragment pairs and long range α particles, as well as fragment triples, are studied. NTE samples are calibrated using Kr and Xe ions with an energy of 1.2 and 3 A MeV.

  15. Microfilters for biomedicine obtained by swift ion processing.

    PubMed

    Torrisi, L

    1997-01-01

    Swift ions with 50 MeV energy are used to irradiate bio-polymeric films. Lithium, carbon and oxygen beams, with fluencies ranging between 10(8) and 10(13) ions/cm2, are swept on large surfaces of hydrogenated and fluorated polymers. The electronic stopping power of the ion induces high rates of ionization, excitation and radical formation along the ion path with production of chain-scission and cross-linking processes which can be investigated by the molecular emission from the irradiated polymer. The radiation damage increases the chemical solubility of the material around the ion track up to distances of the order of 100 nm. A suitable chemical etching removes the damaged material leaving micrometric holes in the polymeric film. This process gives rise to micro-perforated films which can be used as microfilters, with sub-micrometric pore dimension, high selectivity and controllable porosity. Their use is very interesting for special applications in ultra- and microfiltration of biological liquids.

  16. Nuclear Track Detectors. Searches for Exotic Particles

    NASA Astrophysics Data System (ADS)

    Giacomelli, G.; Togo, V.

    We used Nuclear Track Detectors (NTD) CR39 and Makrofol for many purposes: (i) Exposures at the SPS and at lower energy accelerator heavy ion beams for calibration purposes and for fragmentation studies. (ii) Searches for GUT and Intermediate Mass Magnetic Monopoles (IMM), nuclearites, Q-balls and strangelets in the cosmic radiation. The MACRO experiment in the Gran Sasso underground lab, with ˜1,000 m2 of CR39 detectors (plus scintillators and streamer tubes), established an upper limit for superheavy GUT poles at the level of 1.4 × 10-16 cm-2 s-1 sr-1for 4 ×10-5<β<1. The SLIM experiment at the high altitude Chacaltaya lab (5,230 m a.s.l.), using 427 m2 of CR39 detectors exposed for 4.22 years, gave an upper limit for IMMs of ˜1.3 × 10-15 cm-2 s-1 sr-1. The experiments yielded interesting upper limits also on the fluxes of the other mentioned exotic particles. (iii) Environmental studies, radiation monitoring, neutron dosimetry.

  17. A microfilter utilizing a polyethersulfone porous membrane with nanopores

    NASA Astrophysics Data System (ADS)

    Gu, Ye; Miki, Norihisa

    2007-11-01

    We present a novel microfilter system used for the selective separation of solutes of molecular sizes 1-2 nm. The microfilter system consists of two layers of micro chambers made of PDMS and one piece of porous membrane made of polyethersulfone (PES) using the wet-phase inversion method. The PES membrane at the center of the two micro chambers acts as a barrier to molecules larger than its pores. A novel method of bonding the PES membrane to PDMS surface was developed in the device fabrication, whereby diffusion in the microfilter was theoretically derived and applied in the filtering evaluation. The filtering capacity of this microfilter for molecules of molecular sizes from 0.3 nm to 6.6 nm was evaluated using solution samples of sodium chloride (NaCl) and fluorescein isothiocyanate (FITC) dextrans with molecular weights of 4k, 20k and 70k, respectively. The filtering experiments indicated that the optimal membrane used for the device was P2S2. This microfilter system with optimal PES membrane was believed to be capable of selective separation at a molecular size barrier of 1-2 nm and also believed to have the potential for use in portable hemodialysis systems.

  18. Diffraction pattern by rotated conical tracks in solid state nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Stevanovic, N.; Markovic, V. M.

    2016-06-01

    The method for determination of diffraction pattern for irregular 3D objects with application on rotated conical tracks in solid state nuclear track detector (SSNTD) wasdescribed in this paper. The model can be applied for different types of the diffraction (Fresnel, Fraunhofer) and arbitrary shapes of the obstacle. By applying the developed model on conical tracks it was fond that diffraction pattern strongly depends from radius, length and rotation angle of the conical tracks. These dependences were investigated in this paper and results can be applied for determination of inner tracks structure via diffraction pattern.

  19. High resolution image measurements of nuclear tracks

    NASA Technical Reports Server (NTRS)

    Shirk, E. K.; Price, P. B.

    1980-01-01

    The striking clarity and high contrast of the mouths of tracks etched in CR-39 plastic detectors allow automatic measurement of track parameters to be made with simple image-recognition equipment. Using a commercially available Vidicon camera system with a microprocessor-controlled digitizer, resolution for normally incident C-12 and N-14 ions at 32 MeV/amu equivalent to a 14sigma separation of adjacent charges was demonstrated.

  20. Discovery of nuclear tracks in interplanetary dust

    NASA Technical Reports Server (NTRS)

    Bradley, J. P.; Brownlee, D. E.

    1984-01-01

    Prior to capture by the Earth's atmosphere individual interplanetary dust particles (IDP's) have allegedly spent up to 10 to the 5th power years as discrete bodies within the interplanetary medium. Observation of tracks in IDP's in the form of solar flare tracks would provide hitherto unknown data about micrometeorites such as: (1) whether an IDP existed in space as an individual particle or as part of a larger meteroid; (2) the degree to which a particle was heated during the trauma of atmospheric entry; (3) residence time of an IDP within the interplanetary medium; and (4) possible hints as to the pre-accretional exposure of component mineral grains to solar or galactic irradiation. Using transmission electron microscopy tracks in several micrometeorites have been successfully identified. All of the studied particles had been retrieved from the stratosphere by U-2 aircraft. Three pristine IDP's (between 5 and 15 micro m diameter) have so far been searched for solar flare tracks, and they have been found in the two smaller particles U2-20B11 (11 micro m) and U2-20B37 (8 micro m).

  1. Nuclear track detection using thermoset polycarbonates derived from pentaerythritol

    NASA Astrophysics Data System (ADS)

    Mandrekar, Vinod K.; Chourasiya, G.; Kalsi, P. C.; Tilve, S. G.; Nadkarni, V. S.

    2010-03-01

    The paper describes the synthesis and performance of two polymers as nuclear track detectors, both having alpha sensitivity higher than that of the widely-used polymer CR-39. A homopolymer (PPETAC) from pentaerythritol tetrakis(allyl carbonate) (PETAC) monomer and its various copolymers with allyl diglycol carbonate (ADC) prepared by cast polymerization were successfully used as nuclear track detectors. The copolymer PETAC:ADC 4:6 weight percent shows maximum alpha sensitivity, almost double that of CR-39 under identical experimental conditions. This copolymer can reveal alpha particle tracks from 239Pu source in about 60 min and 252Cf fission fragment tracks by chemical etching in less than 30 min, compared to about 120 min and 45 min respectively, required by CR-39. The polymers can be conveniently etched using aqueous sodium hydroxide.

  2. 3D visualisation and analysis of single and coalescing tracks in Solid state Nuclear Track Detectors

    NASA Astrophysics Data System (ADS)

    Wertheim, David; Gillmore, Gavin; Brown, Louise; Petford, Nick

    2010-05-01

    Exposure to radon gas (222Rn) and associated ionising decay products can cause lung cancer in humans (1). Solid state Nuclear Track Detectors (SSNTDs) can be used to monitor radon concentrations (2). Radon particles form tracks in the detectors and these tracks can be etched in order to enable 2D surface image analysis. We have previously shown that confocal microscopy can be used for 3D visualisation of etched SSNTDs (3). The aim of the study was to further investigate track angles and patterns in SSNTDs. A 'LEXT' confocal laser scanning microscope (Olympus Corporation, Japan) was used to acquire 3D image datasets of five CR-39 plastic SSNTD's. The resultant 3D visualisations were analysed by eye and inclination angles assessed on selected tracks. From visual assessment, single isolated tracks as well as coalescing tracks were observed on the etched detectors. In addition varying track inclination angles were observed. Several different patterns of track formation were seen such as single isolated and double coalescing tracks. The observed track angles of inclination may help to assess the angle at which alpha particles hit the detector. Darby, S et al. Radon in homes and risk of lung cancer : collaborative analysis of individual data from 13 European case-control studies. British Medical Journal 2005; 330, 223-226. Phillips, P.S., Denman, A.R., Crockett, R.G.M., Gillmore, G., Groves-Kirkby, C.J., Woolridge, A., Comparative Analysis of Weekly vs. Three monthly radon measurements in dwellings. DEFRA Report No., DEFRA/RAS/03.006. (2004). Wertheim D, Gillmore G, Brown L, and Petford N. A new method of imaging particle tracks in Solid State Nuclear Track Detectors. Journal of Microscopy 2010; 237: 1-6.

  3. BACKPRESSURE TESTING OF ROTARY MICROFILTER DISKS

    SciTech Connect

    Fowley, M.; Herman, D.

    2011-04-14

    The Savannah River National Laboratory (SRNL), under the Department of Energy (DOE) Office of Environmental Management (EM), is modifying and testing the SpinTek{trademark} rotary microfilter (RMF) for radioactive filtration service in the Department of Energy (DOE) complex. The RMF has been shown to improve filtration throughput when compared to other conventional methods such as cross-flow filtration. A concern with the RMF was that backpressure, or reverse flow through the disk, would damage the filter membranes. Reverse flow might happen as a result of an inadvertent valve alignment during flushing. Testing was completed in the Engineering Development Laboratory (EDL) located in SRNL to study the physical effects of backpressure as well as to determine the maximum allowable back-pressure for RMF disks. The RMF disks tested at the EDL were manufactured by SpinTek{trademark} Filtration and used a Pall Corporation PMM050 filter membrane (0.5 micron nominal pore size) made from 316L stainless steel. Early versions of the RMF disks were made from synthetic materials that were incompatible with caustic solutions and radioactive service as well as being susceptible to delaminating when subjected to backpressure. Figure 1-1 shows the essential components of the RMF; 3 rotating disks and 3 stationary turbulence promoters (or shear elements) are shown. Figure 1-2 show the assembly view of a 25 disk RMF proposed for use at the Savannah River Site (SRS) and at the Hanford Facility. The purpose of the testing discussed in this report was to determine the allowable backpressure for RMF disks as well as study the physical effects of backpressure on RMF disks made with the Pall PMM050 membrane. This was accomplished by pressurizing the disks in the reverse flow direction (backpressure) until the test limit was reached or until membrane failure occurred. Backpressure was applied to the disks with air while submerged in deionized (DI) water. This method provided a visual

  4. Effects of etching time on alpha tracks in solid state nuclear track detectors.

    PubMed

    Gillmore, Gavin; Wertheim, David; Crust, Simon

    2017-01-01

    Solid State Nuclear Track Detectors (SSNTDs) are used extensively for monitoring alpha particle radiation, neutron flux and cosmic ray radiation. Radon gas inhalation is regarded as being a significant contributory factor to lung cancer deaths in the UK each year. Gas concentrations are often monitored using CR39 based SSNTDs as the natural decay of radon results in alpha particles which form tracks in these detectors. Such tracks are normally etched for about 4h to enable microscopic analysis. This study examined the effect of etching time on the appearance of alpha tracks in SSNTDs by collecting 2D and 3D image datasets using laser confocal microscope imaging techniques. Etching times of 2 to 4h were compared and marked differences were noted in resultant track area. The median equivalent diameters of tracks were 20.2, 30.2 and 38.9μm for etching at 2, 3 and 4h respectively. Our results indicate that modern microscope imaging can detect and image the smaller size tracks seen for example at 3h etching time. Shorter etching times may give rise to fewer coalescing tracks although there is a balance to consider as smaller track sizes may be more difficult to image. Thus etching for periods of less than 4h clearly merits further investigation as this approach has the potential to improve accuracy in assessing the number of tracks. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Effects of etching time on alpha tracks in Solid state Nuclear Track Detectors

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin; Wertheim, David; Crust, Simon

    2013-04-01

    Inhalation of radon gas is thought to be the cause of about 1100 lung cancer related deaths each year in the UK (1). Radon concentrations can be monitored using Solid State Nuclear Track Detectors (SSNTDs) as the natural decay of radon results in alpha particles which form tracks in the detectors and these tracks can be etched in order to enable microscopic analysis. We have previously shown that confocal microscopy can be used for 3D visualisation of etched SSNTDs (2, 3). The aim of the study was to examine the effect of etching time on the appearance of alpha tracks in SSNTDs. Six SSNTDs were placed in a chamber with a luminous dial watch for a fixed period. The detectors were etched for between 30 minutes and 4.5 hours using 6M NaOH at a temperature of 90oC. A 'LEXT' OLS4000 confocal laser scanning microscope (Olympus Corporation, Japan) was used to acquire 2D and 3D image datasets of CR-39 plastic SSNTDs. Confocal microscope 3D images were acquired using a x50 or x100 objective lens. Data were saved as images and also spreadsheet files with height measurements. Software was written using MATLAB (The MathWorks Inc., USA) to analyse the height data. Comparing the 30 minute and 4 hour etching time detectors, we observed that there were marked differences in track area; the lower the etching time the smaller the track area. The degree to which etching may prevent visualising adjacent tracks also requires further study as it is possible that etching could result in some tracks being subsumed in other tracks. On the other hand if there is too little etching, track sizes would be reduced and hence could be more difficult to image; thus there is a balance required to obtain suitable measurement accuracy. (1) Gray A, Read S, McGale P and Darby S. Lung cancer deaths from indoor radon and the cost effectiveness and potential of policies to reduce them. BMJ 2009; 338: a3110. (2) Wertheim D, Gillmore G, Brown L, and Petford N. A new method of imaging particle tracks in

  6. Adhesion layer for etching of tracks in nuclear trackable materials

    DOEpatents

    Morse, Jeffrey D.; Contolini, Robert J.

    2001-01-01

    A method for forming nuclear tracks having a width on the order of 100-200 nm in nuclear trackable materials, such as polycarbonate (LEXAN) without causing delamination of the LEXAN. The method utilizes an adhesion film having a inert oxide which allows the track to be sufficiently widened to >200 nm without delamination of the nuclear trackable materials. The adhesion film may be composed of a metal such as Cr, Ni, Au, Pt, or Ti, or composed of a dielectric having a stable surface, such as silicon dioxide (SiO.sub.2), silicon nitride (SiN.sub.x), and aluminum oxide (AlO). The adhesion film can either be deposited on top of the gate metal layer, or if the properties of the adhesion film are adequate, it can be used as the gate layer. Deposition of the adhesion film is achieved by standard techniques, such as sputtering or evaporation.

  7. Nuclear track records in the Abee enstatite chondrite

    NASA Technical Reports Server (NTRS)

    Goswami, J. N.

    1983-01-01

    A determination of preatmospheric mass and a delineation of cosmic ray exposure history are made, through the study of nuclear track records in 14 samples taken from different locations of an Abee enstatite chondrite cut slab. Measured track densities in different samples range from 10,000 to 1,000,000/sq cm. Excess tracks of fissiogenic origin were found near the grain edges and across cleavage planes in eight enstatite grains out of the 300 analyzed. The track data rule out preirradiation of any of the analyzed samples with shielding of less than a few tens of cm. The isotrack density contours on the plane of the slab imply an asymmetric ablation of the Abee chondrite during its atmospheric transit. A sphere of about 30 cm radius approximates the preatmospheric shape and size of the Abee meteorite, which underwent a 70% mass loss during ablation.

  8. Vapor etching of nuclear tracks in dielectric materials

    DOEpatents

    Musket, Ronald G.; Porter, John D.; Yoshiyama, James M.; Contolini, Robert J.

    2000-01-01

    A process involving vapor etching of nuclear tracks in dielectric materials for creating high aspect ratio (i.e., length much greater than diameter), isolated cylindrical holes in dielectric materials that have been exposed to high-energy atomic particles. The process includes cleaning the surface of the tracked material and exposing the cleaned surface to a vapor of a suitable etchant. Independent control of the temperatures of the vapor and the tracked materials provide the means to vary separately the etch rates for the latent track region and the non-tracked material. As a rule, the tracked regions etch at a greater rate than the non-tracked regions. In addition, the vapor-etched holes can be enlarged and smoothed by subsequent dipping in a liquid etchant. The 20-1000 nm diameter holes resulting from the vapor etching process can be useful as molds for electroplating nanometer-sized filaments, etching gate cavities for deposition of nano-cones, developing high-aspect ratio holes in trackable resists, and as filters for a variety of molecular-sized particles in virtually any liquid or gas by selecting the dielectric material that is compatible with the liquid or gas of interest.

  9. UV Enhancement of CR-39 Nuclear Track Detector Etch Parameters

    NASA Astrophysics Data System (ADS)

    Traynor, Nathan; McLauchlin, Christopher; Dodge, Kenneth; McLean, James; Padalino, Stephen; Burke, Michelle; Sangster, Craig

    2014-03-01

    CR-39 plastic is an effective and commonly used solid state nuclear track detector. High-energy charged particles leave tracks of chemical damage. When CR-39 is chemically etched with NaOH at elevated temperatures, pits are produced at the track sites that are measurable by an optical microscope. We have shown that by exposing the CR-39 to high intensity UV light between nuclear irradiation and chemical etching, the rate at which the pits grow during etching is increased. The effect has been observed for wavelengths shorter than 350 nm, to at least 250 nm. Heating of samples during UV exposure dramatically increases the etch rates, although heating alone does not produce the effect. The pit enhancement is the result of an increase in both the bulk and track etch rates, while the ratio of these rates (which determines sensitivity to particles) remains roughly constant. By determining the best processing parameters, this effect promises to significantly reduce the time required to process CR-39 track detectors. Funded in part by a grant from the DOE through the Laboratory for Laser Energetics.

  10. New readout system for submicron tracks with nuclear emulsion

    NASA Astrophysics Data System (ADS)

    Katsuragawa, T.; Umemoto, A.; Yoshimoto, M.; Naka, T.; Asada, T.

    2017-04-01

    In this paper, we summarize a newly developed automatic readout system, composed of a microscope with an optics stage, to analyze charged particle tracks of less than 1 μm recorded in a fine-grained nuclear emulsion. This system's optics have the high spatial resolution, epi-illumination, and xenon-mercury lamp necessary to achieve sufficient contrast and brightness for small silver grains up to about 40 nm in diameter. Methods of shape recognition and focus point acquisition were developed that enabled the system to identify submicron tracks corresponding to nuclei on the order of 10-100 keV.

  11. Tracking of Nuclear Production using Indigenous Species: Final LDRD Report

    SciTech Connect

    Alam, Todd Michael; Alam, Mary Kathleen; McIntyre, Sarah K.; Volk, David; Neerathilingam, Muniasamy; Luxon, Bruce A.; Ansari, G. A. Shakeel

    2009-10-01

    Our LDRD research project sought to develop an analytical method for detection of chemicals used in nuclear materials processing. Our approach is distinctly different than current research involving hardware-based sensors. By utilizing the response of indigenous species of plants and/or animals surrounding (or within) a nuclear processing facility, we propose tracking 'suspicious molecules' relevant to nuclear materials processing. As proof of concept, we have examined TBP, tributylphosphate, used in uranium enrichment as well as plutonium extraction from spent nuclear fuels. We will compare TBP to the TPP (triphenylphosphate) analog to determine the uniqueness of the metabonomic response. We show that there is a unique metabonomic response within our animal model to TBP. The TBP signature can further be delineated from that of TPP. We have also developed unique methods of instrumental transfer for metabonomic data sets.

  12. Microbial quality of drinking water from microfiltered water dispensers.

    PubMed

    Sacchetti, R; De Luca, G; Dormi, A; Guberti, E; Zanetti, F

    2014-03-01

    A comparison was made between the microbial quality of drinking water obtained from Microfiltered Water Dispensers (MWDs) and that of municipal tap water. A total of 233 water samples were analyzed. Escherichia coli (EC), enterococci (ENT), total coliforms (TC), Staphylococcus aureus, Pseudomonas aeruginosa and heterotrophic plate count (HPC) at 22 °C and 37 °C were enumerated. In addition, information was collected about the principal structural and functional characteristics of each MWD in order to study the various factors that might influence the microbial quality of the water. EC and ENT were not detected in any of the samples. TC were never detected in the tap water but were found in 5 samples taken from 5 different MWDs. S. aureus was found in a single sample of microfiltered water. P. aeruginosa was found more frequently and at higher concentrations in the samples collected from MWDs. The mean HPCs at 22 °C and 37 °C were significantly higher in microfiltered water samples compared to those of the tap water. In conclusion, the use of MWDs may increase the number of bacteria originally present in tap water. It is therefore important to monitor the quality of the dispensed water over time, especially if it is destined for vulnerable users. Copyright © 2013 Elsevier GmbH. All rights reserved.

  13. Evaluation of Alternative Filter Media for the Rotary Microfilter

    SciTech Connect

    Poirier, M. R.; Herman, D. T.; Bhave, R.

    2011-11-09

    The Savannah River Site is currently developing and testing several processes to treat high level radioactive liquid waste. Each of these processes has a solid-liquid separation process that limits its throughput. Savannah River National Laboratory researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The authors believe the rotary microfilter throughput can be improved by using a better filter membrane. Previous testing showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. Savannah River National Laboratory and Oak Ridge National Laboratory are working together to develop asymmetric ceramic ? stainless steel composite filters and asymmetric 100% stainless steel filters to improve the throughput of the rotary microfilter. The Oak Ridge National Laboratory Inorganic Membrane Group fabricated samples of alternative filter membranes. In addition, Savannah River National Laboratory obtained samples of filter membranes from Pall, Porvair, and SpinTek. They tested these samples in a static test cell with feed slurries containing monosodium titanate and simulated sludge.

  14. Nuclear particle detection using a track-recording solid

    NASA Technical Reports Server (NTRS)

    Weber, M.; Weber, D.

    1984-01-01

    The design of the nuclear particle detector located in Purdue University's Get Away Special package which was flown aboard STS-7 is detailed. The experiment consisted of a stack of particle-detecting polymer sheets. The sheets show positive results of tracks throughout the block. A slide of each sheet was made for further analysis. Recommendations for similar experiments performed in the future are discussed.

  15. Nuclear track membranes: Production in nuclear reactors and prospects of application

    SciTech Connect

    Fursov, B.I.; Kryuchkov, E.A.; Mironov, N.N.

    1993-12-31

    Nuclear track membranes are produced by a physico-chemical treatment of polymeric films exposed to fission fragments in nuclear reactors or to heavy ion beams. Heavy charged particles form in the solids along their trajectories regions of high ionization density where polymer destruction takes place. Selective dissolution of damaged material converts the initial film into a microfiltration membrane with cylindrical through pores. The main feature of nuclear membranes are a small thickness and uniformity of pore size. The qualities of the nuclear membranes promise good prospects for applications in many areas.

  16. In-laboratory development of an automatic track counting system for solid state nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Uzun, Sefa Kemal; Demiröz, Işık; Ulus, İzzet

    2017-01-01

    In this study, an automatic track counting system was developed for solid state nuclear track detectors (SSNTD). Firstly the specifications of required hardware components were determined, and accordingly the CCD camera, microscope and stage motor table was supplied and integrated. The system was completed by developing parametric software with VB.Net language. Finally a set of test intended for radon activity concentration measurement was applied. According to the test results, the system was enabled for routine radon measurement. Whether the parameters of system are adjusted for another SSNTD application, it could be used for other fields of SSNTD like neutron dosimetry or heavy charged particle detection.

  17. Determination of nuclear tracks parameters on sequentially etched PADC detectors

    NASA Astrophysics Data System (ADS)

    Horwacik, Tomasz; Bilski, Pawel; Koerner, Christine; Facius, Rainer; Berger, Thomas; Nowak, Tomasz; Reitz, Guenther; Olko, Pawel

    Polyallyl Diglycol Carbonate (PADC) detectors find many applications in radiation protection. One of them is the cosmic radiation dosimetry, where PADC detectors measure the linear energy transfer (LET) spectra of charged particles (from protons to heavy ions), supplementing TLD detectors in the role of passive dosemeter. Calibration exposures to ions of known LET are required to establish a relation between parameters of track observed on the detector and LET of particle creating this track. PADC TASTRAK nuclear track detectors were exposed to 12 C and 56 Fe ions of LET in H2 O between 10 and 544 keV/µm. The exposures took place at the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan in the frame of the HIMAC research project "Space Radiation Dosimetry-Ground Based Verification of the MATROSHKA Facility" (20P-240). Detectors were etched in water solution of NaOH with three different temperatures and for various etching times to observe the appearance of etched tracks, the evolution of their parameters and the stability of the etching process. The applied etching times (and the solution's concentrations and temperatures) were: 48, 72, 96, 120 hours (6.25 N NaOH, 50 O C), 20, 40, 60, 80 hours (6.25 N NaOH, 60 O C) and 8, 12, 16, 20 hours (7N NaOH, 70 O C). The analysis of the detectors involved planimetric (2D) measurements of tracks' entrance ellipses and mechanical measurements of bulk layer thickness. Further track parameters, like angle of incidence, track length and etch rate ratio were then calculated. For certain tracks, results of planimetric measurements and calculations were also compared with results of optical track profile (3D) measurements, where not only the track's entrance ellipse but also the location of the track's tip could be directly measured. All these measurements have been performed with the 2D/3D measurement system at DLR. The collected data allow to create sets of V(LET in H2 O) calibration curves suitable for short, intermediate and

  18. EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER

    SciTech Connect

    Poirier, M.; Herman, D.; Bhave, R.

    2011-09-13

    SRS is currently developing and testing several processes to treat high level radioactive liquid waste. These processes include the Integrated Salt Disposition Process (ISDP), the Salt Waste Processing Facility (SWPF), and the Small Column Ion Exchange Process (SCIX). Each of these processes has a solid-liquid separation process that limits its throughput. SRNL researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The testing showed significant improvement in filter flux with the rotary microfilter over the baseline crossflow filter (i.e., 2.5-6.5X during scoping tests, as much as 10X in actual waste tests, and approximately 3X in pilot-scale tests). SRNL received funding from DOE EM-21, and subsequently DOE EM-31 to develop the rotary microfilter for high level radioactive service. The work has included upgrading the rotary microfilter for radioactive service, testing with simulated SRS waste streams, and testing it with simulated Hanford waste streams. While the filtration rate is better than that obtained during testing of crossflow filters, the authors believe the rotary microfilter throughput can be improved by using a better filter membrane. The rotary microfilter membrane is made of stainless steel (Pall PMM050). Previous testing, funded by DOE EM-21, showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. In that testing, the Pall Accusep and Graver filters produced 13-21% larger filter flux than the baseline 0.1 {micro}m Mott filter. While the improvement in flux is not as dramatic as the improvement of the rotary filter over a crossflow filter, a 13-21% increase could reduce the lifetime of a 30 year process by 4-6 years, with significant cost savings. Subsequent rotary filter testing showed the Pall PMM050 stainless steel filter membrane produced

  19. Atmospheric heating of meteorites: Results from nuclear track studies

    NASA Technical Reports Server (NTRS)

    Jha, R.

    1984-01-01

    A quantitative model to estimate the degree of annealing of nuclear tracks in mineral grains subjected to a variable temperature history was proposed. This model is applied to study the track annealing records in different meteorites resulting from their atmospheric heating. Scale lengths were measured of complete and partial track annealing, delta X sub 1 and delta X sub 2, respectively. In mineral grain close to fusion crust in about a dozen meteorites. Values of delta X sub 1 and delta X sub 2 depend on extent and duration of heating during atmospheric transit and hence on meteorite entry parameters. To estimate track annealing, the temperature history during atmospheric heating at different distances from the crusted surface of the meteorite is obtained by solving heat conduction equation in conjunction with meteorite entry model, and use of the annealing model to evaluate the degree of annealing of tracks. It is shown that the measured values of delta X sub 1 and delta X sub 2 in three of the meteorites studied are consistent with values using preatmospheric mass, entry velocity and entry angle of these meteorites.

  20. Atmospheric heating of meteorites: Results from nuclear track studies

    NASA Technical Reports Server (NTRS)

    Jha, R.

    1984-01-01

    A quantitative model to estimate the degree of annealing of nuclear tracks in mineral grains subjected to a variable temperature history was proposed. This model is applied to study the track annealing records in different meteorites resulting from their atmospheric heating. Scale lengths were measured of complete and partial track annealing, delta X sub 1 and delta X sub 2, respectively. In mineral grain close to fusion crust in about a dozen meteorites. Values of delta X sub 1 and delta X sub 2 depend on extent and duration of heating during atmospheric transit and hence on meteorite entry parameters. To estimate track annealing, the temperature history during atmospheric heating at different distances from the crusted surface of the meteorite is obtained by solving heat conduction equation in conjunction with meteorite entry model, and use of the annealing model to evaluate the degree of annealing of tracks. It is shown that the measured values of delta X sub 1 and delta X sub 2 in three of the meteorites studied are consistent with values using preatmospheric mass, entry velocity and entry angle of these meteorites.

  1. Guidance for identifying, reporting and tracking nuclear safety noncompliances

    SciTech Connect

    1995-12-01

    This document provides Department of Energy (DOE) contractors, subcontractors and suppliers with guidance in the effective use of DOE`s Price-Anderson nuclear safety Noncompliance Tracking System (NTS). Prompt contractor identification, reporting to DOE, and correction of nuclear safety noncompliances provides DOE with a basis to exercise enforcement discretion to mitigate civil penalties, and suspend the issuance of Notices of Violation for certain violations. Use of this reporting methodology is elective by contractors; however, this methodology is intended to reflect DOE`s philosophy on effective identification and reporting of nuclear safety noncompliances. To the extent that these expectations are met for particular noncompliances, DOE intends to appropriately exercise its enforcement discretion in considering whether, and to what extent, to undertake enforcement action.

  2. Textual and shape-based feature extraction and neuro-fuzzy classifier for nuclear track recognition

    NASA Astrophysics Data System (ADS)

    Khayat, Omid; Afarideh, Hossein

    2013-04-01

    Track counting algorithms as one of the fundamental principles of nuclear science have been emphasized in the recent years. Accurate measurement of nuclear tracks on solid-state nuclear track detectors is the aim of track counting systems. Commonly track counting systems comprise a hardware system for the task of imaging and software for analysing the track images. In this paper, a track recognition algorithm based on 12 defined textual and shape-based features and a neuro-fuzzy classifier is proposed. Features are defined so as to discern the tracks from the background and small objects. Then, according to the defined features, tracks are detected using a trained neuro-fuzzy system. Features and the classifier are finally validated via 100 Alpha track images and 40 training samples. It is shown that principle textual and shape-based features concomitantly yield a high rate of track detection compared with the single-feature based methods.

  3. A parameterization of nuclear track profiles in CR-39 detector

    NASA Astrophysics Data System (ADS)

    Azooz, A. A.; Al-Nia'emi, S. H.; Al-Jubbori, M. A.

    2012-11-01

    on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage. No. of lines in distributed program, including test data, etc.: 15598 No. of bytes in distributed program, including test data, etc.: 3933244 Distribution format: tar.gz Programming language: MATLAB. Computer: Any Desktop or Laptop. Operating system: Windows 1998 or above (with MATLAB R13 or above installed). RAM: 512 Megabytes or higher Classification: 17.5. Nature of problem: A new semispherical parameterization of charged particle tracks in CR-39 SSNTD is carried out in a previous paper. This parameterization is developed here into a MATLAB based software to calculate the track length and track profile for any proton or alpha particle energy or etching time. This software is intended to compete with the TRACK_TEST [1] and TRACK_VISION [2] software currently in use by all people working in the field of SSNTD. Solution method: Based on fitting of experimental results of protons and alpha particles track lengths for various energies and etching times to a new semispherical formula with four free fitting parameters, the best set of energy independent parameters were found. These parameters are introduced into the software and the software is programmed to solve the set of equations to calculate the track depth, track etching rate as a function of both time and residual range for particles of normal and oblique incidence, the track longitudinal profile at both normal and oblique incidence, and the three dimensional track profile at normal incidence. Running time: 1-8 s on Pentium (4) 2 GHz CPU, 3 GB of RAM depending on the etching time value References: [1] ADWT_v1_0 Track_Test Computer program TRACK_TEST for calculating parameters and plotting profiles for etch pits in nuclear track materials. D. Nikezic, K.N. Yu Comput. Phys. Commun. 174(2006)160 [2] AEAF

  4. Automated Track Recognition and Event Reconstruction in Nuclear Emulsion

    NASA Technical Reports Server (NTRS)

    Deines-Jones, P.; Cherry, M. L.; Dabrowska, A.; Holynski, R.; Jones, W. V.; Kolganova, E. D.; Kudzia, D.; Nilsen, B. S.; Olszewski, A.; Pozharova, E. A.; Sengupta, K.; Szarska, M.; Trzupek, A.; Waddington, C, J.; Wefel, J. P.; Wilczynska, B.; Wilczynski, H.; Wolter, W.; Wosiek, B.; Wozniak, K.

    1998-01-01

    The major advantages of nuclear emulsion for detecting charged particles are its submicron position resolution and sensitivity to minimum ionizing particles. These must be balanced, however, against the difficult manual microscope measurement by skilled observers required for the analysis. We have developed an automated system to acquire and analyze the microscope images from emulsion chambers. Each emulsion plate is analyzed independently, allowing coincidence techniques to be used in order to reject back- ground and estimate error rates. The system has been used to analyze a sample of high-multiplicity Pb-Pb interactions (charged particle multiplicities approx. 1100) produced by the 158 GeV/c per nucleon Pb-208 beam at CERN. Automatically reconstructed track lists agree with our best manual measurements to 3%. We describe the image analysis and track reconstruction techniques, and discuss the measurement and reconstruction uncertainties.

  5. Nuclear track-based biosensors with the enzyme laccase

    NASA Astrophysics Data System (ADS)

    García-Arellano, H.; Fink, D.; Muñoz Hernández, G.; Vacík, J.; Hnatowicz, V.; Alfonta, L.

    2014-08-01

    A new type of biosensors for detecting phenolic compounds is presented here. These sensors consist of thin polymer foils with laccase-clad etched nuclear tracks. The presence of suitable phenolic compounds in the sensors leads to the formation of enzymatic reaction products in the tracks, which differ in their electrical conductivities from their precursor materials. These differences correlate with the concentrations of the phenolic compounds. Corresponding calibration curves have been established for a number of compounds. The sensors thus produced are capable to cover between 5 and 9 orders of magnitude in concentration - in the best case down to some picomoles. The sensor's detection sensitivity strongly depends on the specific compound. It is highest for caffeic acid and acid blue 74, followed by ABTS and ferulic acid.

  6. Basic nature of nuclear track membranes for liquid media

    NASA Astrophysics Data System (ADS)

    Guo, Shi-Lun

    1998-09-01

    Nuclear track membranes (NTM), because of their straight pore structures and unitary pore size, will become indispensable materials in future science and technology. After steady development since the 1960's, nuclear track membranes have been widely used in various fields. Extensive detail of their nature and properties are now recognized. A review is given of the nature and properties of nuclear track membranes in the case of liquid media passing through the membranes. The following subjects are included here: (1) For pure liquid media the applicability and limitation of Poiseuille's formula to the calculation of flow rates have been discussed. Several techniques for the determination of liquid viscosity with NTM's have been developed and successfully tested and classified, either as absolute or relative; the latter is further sub-classified either as an absolute or kinematic viscosity determination. (2) For liquid solutions a method for solute concentration determination with NTM's has been conceived and tested. These tests show that NTM's are unique and simple devices when applied to the determination of chemical concentrations of many substances in various solvents. (3) For liquid mixtures, such as oil in water, separation of different phases of liquids can be accelerated by using NTM's. This technique can be used in the purification of liquids. The principle and application of liquid phase separation to chemical separations are also explored. (4) Blocking phenomenon of NTM's by liquids containing microscopic solid particles have been studied and a blocking formula to calculate the flow rate of liquids containing solid particles is derived. By fitting the formula to measured data of flow rates we can estimate the number, size and shape of the solid particulates suspended in a unit volume of the liquid. Finally (5), for liquids containing bacteria, filtration of bacteria with NTM's has been studied in detail. Some basic rules and key factors are suggested for

  7. Irradiation of nuclear track emulsions with thermal neutrons, heavy ions, and muons

    SciTech Connect

    Artemenkov, D. A. Bradnova, V.; Zaitsev, A. A.; Zarubin, P. I.; Zarubina, I. G.; Kattabekov, R. R.; Mamatkulov, K. Z.; Rusakova, V. V.

    2015-07-15

    Exposures of test samples of nuclear track emulsion were analyzed. Angular and energy correlations of products originating from the thermal-neutron-induced reaction n{sub th} +{sup 10} B → {sup 7} Li + (γ)+ α were studied in nuclear track emulsions enriched in boron. Nuclear track emulsions were also irradiated with {sup 86}Kr{sup +17} and {sup 124}Xe{sup +26} ions of energy about 1.2 MeV per nucleon. Measurements of ranges of heavy ions in nuclear track emulsionsmade it possible to determine their energies on the basis of the SRIM model. The formation of high-multiplicity nuclear stars was observed upon irradiating nuclear track emulsions with ultrarelativistic muons. Kinematical features studied in this exposure of nuclear track emulsions for events of the muon-induced splitting of carbon nuclei to three alpha particles are indicative of the nucleardiffraction interaction mechanism.

  8. Nuclear fragmentation and the number of particle tracks in tissue.

    PubMed

    Ponomarev, A L; Cucinotta, F A

    2006-01-01

    For high energy nuclei, the number of particle tracks per cell is modified by local nuclear reactions that occur, with large fluctuations expected for heavy ion tracks. Cells near the interaction site of a reaction will experience a much higher number of tracks than estimated by the average fluence. Two types of reaction products are possible and occur in coincidence; projectile fragments, which generally have smaller charge and similar velocity to that of the projectile, and target fragments, which are produced from the fragmentation of the nuclei of water atoms or other cellular constituents with low velocity. In order to understand the role of fragmentation in biological damage a new model of human tissue irradiated by heavy ions was developed. A box of the tissue is modelled with periodic boundary conditions imposed, which extrapolates the technique to macroscopic volumes of tissue. The cross sections for projectile and target fragmentation products are taken from the quantum multiple scattering fragmentation code previously developed at NASA Johnson Space Center. Statistics of fragmentation pathways occurring in a cell monolayer, as well as in a small volume of 10 x 10 x 10 cells are given. A discussion on approaches to extend the model to describe spatial distributions of inactivated or other cell damage types, as well as highly organised tissues of multiple cell types, is presented.

  9. Ion track reconstruction in 3D using alumina-based fluorescent nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Niklas, M.; Bartz, J. A.; Akselrod, M. S.; Abollahi, A.; Jäkel, O.; Greilich, S.

    2013-09-01

    Fluorescent nuclear track detectors (FNTDs) based on Al2O3: C, Mg single crystal combined with confocal microscopy provide 3D information on ion tracks with a resolution only limited by light diffraction. FNTDs are also ideal substrates to be coated with cells to engineer cell-fluorescent ion track hybrid detectors (Cell-Fit-HD). This radiobiological tool enables a novel platform linking cell responses to physical dose deposition on a sub-cellular level in proton and heavy ion therapies. To achieve spatial correlation between single ion hits in the cell coating and its biological response the ion traversals have to be reconstructed in 3D using the depth information gained by the FNTD read-out. FNTDs were coated with a confluent human lung adenocarcinoma epithelial (A549) cell layer. Carbon ion irradiation of the hybrid detector was performed perpendicular and angular to the detector surface. In situ imaging of the fluorescently labeled cell layer and the FNTD was performed in a sequential read-out. Making use of the trajectory information provided by the FNTD the accuracy of 3D track reconstruction of single particles traversing the hybrid detector was studied. The accuracy is strongly influenced by the irradiation angle and therefore by complexity of the FNTD signal. Perpendicular irradiation results in highest accuracy with error of smaller than 0.10°. The ability of FNTD technology to provide accurate 3D ion track reconstruction makes it a powerful tool for radiobiological investigations in clinical ion beams, either being used as a substrate to be coated with living tissue or being implanted in vivo.

  10. Solid State Nuclear Track Detectors--I: Track Characteristics and Formation Mechanisms.

    ERIC Educational Resources Information Center

    Lal, Nand

    1991-01-01

    Heavily ionizing charged particles produce radiation damage tracks in a wide variety of insulating materials. The experimental properties of these tracks and track recorders are described. The mechanisms by which the tracks are produced are discussed. (Author/KR)

  11. 3D imaging of particle tracks in Solid State Nuclear Track Detectors

    NASA Astrophysics Data System (ADS)

    Wertheim, D.; Gillmore, G.; Brown, L.; Petford, N.

    2009-04-01

    Inhalation of radon gas (222Rn) and associated ionizing decay products is known to cause lung cancer in human. In the U.K., it has been suggested that 3 to 5 % of total lung cancer deaths can be linked to elevated radon concentrations in the home and/or workplace. Radon monitoring in buildings is therefore routinely undertaken in areas of known risk. Indeed, some organisations such as the Radon Council in the UK and the Environmental Protection Agency in the USA, advocate a ‘to test is best' policy. Radon gas occurs naturally, emanating from the decay of 238U in rock and soils. Its concentration can be measured using CR?39 plastic detectors which conventionally are assessed by 2D image analysis of the surface; however there can be some variation in outcomes / readings even in closely spaced detectors. A number of radon measurement methods are currently in use (for examples, activated carbon and electrets) but the most widely used are CR?39 solid state nuclear track?etch detectors (SSNTDs). In this technique, heavily ionizing alpha particles leave tracks in the form of radiation damage (via interaction between alpha particles and the atoms making up the CR?39 polymer). 3D imaging of the tracks has the potential to provide information relating to angle and energy of alpha particles but this could be time consuming. Here we describe a new method for rapid high resolution 3D imaging of SSNTDs. A ‘LEXT' OLS3100 confocal laser scanning microscope was used in confocal mode to successfully obtain 3D image data on four CR?39 plastic detectors. 3D visualisation and image analysis enabled characterisation of track features. This method may provide a means of rapid and detailed 3D analysis of SSNTDs. Keywords: Radon; SSNTDs; confocal laser scanning microscope; 3D imaging; LEXT

  12. Application of fluorescent nuclear track detectors for cellular dosimetry.

    PubMed

    Rahmanian, S; Niklas, M; Abdollahi, A; Jäkel, O; Greilich, S

    2017-04-07

    Ion beams radiotherapy with charged particles show greater relative biological effectiveness (RBE) compared to conventional photon therapy. This enhanced RBE is due to a localized energy deposition pattern, which is subject to large fluctuations on cellular scales. Fluorescent nuclear track detectors (FNTDs) based on Al2O3:C,Mg crystals coated with cells (Cell-Fit-HD) can provide information on individual cellular energy deposition. In this study we provide a theoretical framework to obtain the distribution of microscopic energy deposition and ionization density in cells exposed to ion beams and identifies contributions of five different sources of variations to the overall energy fluctuation at different depths of a biologically optimized spread-out Bragg peak. We show that fluctuation in the individual energy loss of the particles is the major source of variability while the fluctuation in particle hits plays a minor role. With the Cell-Fit-HD system the uncertainty arising from four of these sources, namely the nucleus area, the number of nuclear hits, the particle linear energy transfer and the chord length can be reduced and only energy loss straggling remains fundamentally unknown. The ability to quantify these factors results in a reduction of the uncertainty in cellular energy deposition from 24-55% down to only 7-12%. We have also shown current experimental results with FNTDs which show promising results, but need further improvements to reach the ideals predicted in this study.

  13. Application of fluorescent nuclear track detectors for cellular dosimetry

    NASA Astrophysics Data System (ADS)

    Rahmanian, S.; Niklas, M.; Abdollahi, A.; Jäkel, O.; Greilich, S.

    2017-04-01

    Ion beams radiotherapy with charged particles show greater relative biological effectiveness (RBE) compared to conventional photon therapy. This enhanced RBE is due to a localized energy deposition pattern, which is subject to large fluctuations on cellular scales. Fluorescent nuclear track detectors (FNTDs) based on Al2O3:C,Mg crystals coated with cells (Cell-Fit-HD) can provide information on individual cellular energy deposition. In this study we provide a theoretical framework to obtain the distribution of microscopic energy deposition and ionization density in cells exposed to ion beams and identifies contributions of five different sources of variations to the overall energy fluctuation at different depths of a biologically optimized spread-out Bragg peak. We show that fluctuation in the individual energy loss of the particles is the major source of variability while the fluctuation in particle hits plays a minor role. With the Cell-Fit-HD system the uncertainty arising from four of these sources, namely the nucleus area, the number of nuclear hits, the particle linear energy transfer and the chord length can be reduced and only energy loss straggling remains fundamentally unknown. The ability to quantify these factors results in a reduction of the uncertainty in cellular energy deposition from 24–55% down to only 7–12%. We have also shown current experimental results with FNTDs which show promising results, but need further improvements to reach the ideals predicted in this study.

  14. Computer program TRACK_TEST for calculating parameters and plotting profiles for etch pits in nuclear track materials

    NASA Astrophysics Data System (ADS)

    Nikezic, D.; Yu, K. N.

    2006-01-01

    A computer program called TRACK_TEST for calculating parameters (lengths of the major and minor axes) and plotting profiles in nuclear track materials resulted from light-ion irradiation and subsequent chemical etching is described. The programming steps are outlined, including calculations of alpha-particle ranges, determination of the distance along the particle trajectory penetrated by the chemical etchant, calculations of track coordinates, determination of the lengths of the major and minor axes and determination of the contour of the track opening. Descriptions of the program are given, including the built-in V functions for the two commonly employed nuclear track materials commercially known as LR 115 (cellulose nitrate) and CR-39 (poly allyl diglycol carbonate) irradiated by alpha particles. Program summaryTitle of the program:TRACK_TEST Catalogue identifier:ADWT Program obtainable from:CPC Program Library, Queen's University of Belfast, N. Ireland Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWT Computer:Pentium PC Operating systems:Windows 95+ Programming language:Fortran 90 Memory required to execute with typical data:256 MB No. of lines in distributed program, including test data, etc.: 2739 No. of bytes in distributed program, including test data, etc.:204 526 Distribution format:tar.gz External subprograms used:The entire code must be linked with the MSFLIB library Nature of problem: Fast heavy charged particles (like alpha particles and other light ions etc.) create latent tracks in some dielectric materials. After chemical etching in aqueous NaOH or KOH solutions, these tracks become visible under an optical microscope. The growth of a track is based on the simultaneous actions of the etchant on undamaged regions (with the bulk etch rate V) and along the particle track (with the track etch rate V). Growth of the track is described satisfactorily by these two parameters ( V and V). Several models have been presented in the past describing

  15. Nuclear track studies of the Pasamonte and Moore County eucrites

    NASA Technical Reports Server (NTRS)

    Wilkening, L. L.

    1977-01-01

    The selective annealing technique was applied to samples from the Pasamonte eucrite with a view to obtaining fission track ages of clasts in the meteorite. The method did not permit cosmic ray tracks to be distinguished from fission tracks in either Pasamonte or Moore County. A difference between the fossil track densities observed in an igneous clast and the surrounding host material appears to be due to a pre-irradiation on the Pasamonte parent planet.

  16. DEVELOPMENT OF A ROTARY MICROFILTER FOR RADIOACTIVE WASTE APPLICATIONS

    SciTech Connect

    Poirier, M; David Herman, D; Samuel Fink, S

    2008-02-25

    The processing rate of Savannah River Site (SRS) high-level waste decontamination processes are limited by the flow rate of the solid-liquid separation. The baseline process, using a 0.1 micron cross-flow filter, produces {approx}0.02 gpm/sq. ft. of filtrate under expected operating conditions. Savannah River National Laboratory (SRNL) demonstrated significantly higher filter flux for actual waste samples using a small-scale rotary filter. With funding from the U. S. Department of Energy Office of Cleanup Technology, SRNL personnel are evaluating and developing the rotary microfilter for radioactive service at SRS. The authors improved the design for the disks and filter unit to make them suitable for high-level radioactive service. They procured two units using the new design, tested them with simulated SRS wastes, and evaluated the operation of the units. Work to date provides the following conclusions and program status: (1) The authors modified the design of the filter disks to remove epoxy and Ryton{reg_sign}. The new design includes welding both stainless steel and ceramic coated stainless steel filter media to a stainless steel support plate. The welded disks were tested in the full-scale unit. They showed good reliability and met filtrate quality requirements. (2) The authors modified the design of the unit, making installation and removal easier. The new design uses a modular, one-piece filter stack that is removed simply by disassembly of a flange on the upper (inlet) side of the filter housing. All seals and rotary unions are contained within the removable stack. (3) While it is extremely difficult to predict the life of the seal, the vendor representative indicates a minimum of one year in present service conditions is reasonable. Changing the seal face material from silicon-carbide to a graphite-impregnated silicon-carbide is expected to double the life of the seal. Replacement of the current seal with an air seal could increase the lifetime to 5 years

  17. 4-D single particle tracking of synthetic and proteinaceous microspheres reveals preferential movement of nuclear particles along chromatin - poor tracks.

    PubMed

    Bacher, Christian P; Reichenzeller, Michaela; Athale, Chaitanya; Herrmann, Harald; Eils, Roland

    2004-11-23

    The dynamics of nuclear organization, nuclear bodies and RNPs in particular has been the focus of many studies. To understand their function, knowledge of their spatial nuclear position and temporal translocation is essential. Typically, such studies generate a wealth of data that require novel methods in image analysis and computational tools to quantitatively track particle movement on the background of moving cells and shape changing nuclei. We developed a novel 4-D image processing platform (TIKAL) for the work with laser scanning and wide field microscopes. TIKAL provides a registration software for correcting global movements and local deformations of cells as well as 2-D and 3-D tracking software. With this new tool, we studied the dynamics of two different types of nuclear particles, namely nuclear bodies made from GFP-NLS-vimentin and microinjected 0.1 mum - wide polystyrene beads, by live cell time-lapse microscopy combined with single particle tracking and mobility analysis. We now provide a tool for the automatic 3-D analysis of particle movement in parallel with the acquisition of chromatin density data. Kinetic analysis revealed 4 modes of movement: confined obstructed, normal diffusion and directed motion. Particle tracking on the background of stained chromatin revealed that particle movement is directly related to local reorganization of chromatin. Further a direct comparison of particle movement in the nucleoplasm and the cytoplasm exhibited an entirely different kinetic behaviour of vimentin particles in both compartments. The kinetics of nuclear particles were slightly affected by depletion of ATP and significantly disturbed by disruption of actin and microtubule networks. Moreover, the hydration state of the nucleus had a strong impact on the mobility of nuclear bodies since both normal diffusion and directed motion were entirely abolished when cells were challenged with 0.6 M sorbitol. This effect correlated with the compaction of chromatin

  18. WE-D-BRF-01: FEATURED PRESENTATION - Investigating Particle Track Structures Using Fluorescent Nuclear Track Detectors and Monte Carlo Simulations

    SciTech Connect

    Dowdell, S; Paganetti, H; Schuemann, J; Greilich, S; Zimmerman, F; Evans, C

    2014-06-15

    Purpose: To report on the efforts funded by the AAPM seed funding grant to develop the basis for fluorescent nuclear track detector (FNTD) based radiobiological experiments in combination with dedicated Monte Carlo simulations (MCS) on the nanometer scale. Methods: Two confocal microscopes were utilized in this study. Two FNTD samples were used to find the optimal microscope settings, one FNTD irradiated with 11.1 MeV/u Gold ions and one irradiated with 428.77 MeV/u Carbon ions. The first sample provided a brightly luminescent central track while the latter is used to test the capabilities to observe secondary electrons. MCS were performed using TOPAS beta9 version, layered on top of Geant4.9.6p02. Two sets of simulations were performed, one with the Geant4-DNA physics list and approximating the FNTDs by water, a second set using the Penelope physics list in a water-approximated FNTD and a aluminum-oxide FNTD. Results: Within the first half of the funding period, we have successfully established readout capabilities of FNTDs at our institute. Due to technical limitations, our microscope setup is significantly different from the approach implemented at the DKFZ, Germany. However, we can clearly reconstruct Carbon tracks in 3D with electron track resolution of 200 nm. A second microscope with superior readout capabilities will be tested in the second half of the funding period, we expect an improvement in signal to background ratio with the same the resolution.We have successfully simulated tracks in FNTDs. The more accurate Geant4-DNA track simulations can be used to reconstruct the track energy from the size and brightness of the observed tracks. Conclusion: We have achieved the goals set in the seed funding proposal: the setup of FNTD readout and simulation capabilities. We will work on improving the readout resolution to validate our MCS track structures down to the nanometer scales.

  19. Formation of nanometer-size wires using infiltration into latent nuclear tracks

    DOEpatents

    Musket, Ronald G.; Felter, Thomas E.

    2002-01-01

    Nanometer-size wires having a cross-sectional dimension of less than 8 nm with controllable lengths and diameters are produced by infiltrating latent nuclear or ion tracks formed in trackable materials with atomic species. The trackable materials and atomic species are essentially insoluble in each other, thus the wires are formed by thermally driven, self-assembly of the atomic species during annealing, or re-crystallization, of the damage in the latent tracks. Unlike conventional ion track lithography, the inventive method does not require etching of the latent tracks.

  20. Current status and prospects of nuclear physics research based on tracking techniques

    NASA Astrophysics Data System (ADS)

    Alekseev, V. A.; Alexandrov, A. B.; Bagulya, A. V.; Chernyavskiy, M. M.; Goncharova, L. A.; Gorbunov, S. A.; Kalinina, G. V.; Konovalova, N. S.; Okatyeva, N. M.; Pavlova, T. A.; Polukhina, N. G.; Shchedrina, T. V.; Starkov, N. I.; Tioukov, V. E.; Vladymirov, M. S.; Volkov, A. E.

    2017-01-01

    Results of nuclear physics research made using track detectors are briefly reviewed. Advantages and prospects of the track detection technique in particle physics, neutrino physics, astrophysics and other fields are discussed on the example of the results of the search for direct origination of tau neutrino in a muon neutrino beam within the framework of the international experiment OPERA (Oscillation Project with Emulsion-tRacking Apparatus) and works on search for superheavy nuclei in nature on base of their tracks in meteoritic olivine crystals. The spectra of superheavy elements in galactic cosmic rays are presented. Prospects of using the track detection technique in fundamental and applied research are reported.

  1. Operational comparison of TLD albedo dosemeters and solid state nuclear tracks detectors in fuel fabrication facilities.

    PubMed

    Tsujimura, N; Takada, C; Yoshida, T; Momose, T

    2007-01-01

    The authors carried out an operational study that compared the use of TLD albedo dosemeters and solid state nuclear tracks detector in plutonium environments of Japan Nuclear Cycle Development Institute, Tokai Works. A selected group of workers engaged in the fabrication process of MOX (Plutonium-Uranium mixed oxide) fuel wore both TLD albedo dosemeters and solid state nuclear tracks detectors. The TL readings were generally proportional to the counted etch-pits, and thus the dose equivalent results obtained from TLD albedo dosemeter agreed with those from solid state nuclear tracks detector within a factor of 1.5. This result indicates that, in the workplaces of the MOX fuel plants, the neutron spectrum remained almost constant in terms of time and space, and the appropriate range of field-specific correction with spectrum variations was small in albedo dosimetry.

  2. A study of commercially-available polyethylene terephthalate (PET) and polycarbonate as nuclear track detector materials

    NASA Astrophysics Data System (ADS)

    Espinosa, G.; Golzarri, J. I.; Vazquez-Lopez, C.; Trejo, R.; Lopez, K.; Rickards, J.

    2014-07-01

    In the study of the sensitivity of materials to be used as nuclear track detectors, it was found that commercial polyethylene terephthalate (PET) from Ciel® water bottles, commercial roof cover polycarbonate, and recycled packaging strips (recycled PET), can be used as nuclear track detectors. These three commercial materials present nuclear tracks when bombarded by 2.27 MeV nitrogen ions produced in a Pelletron particle accelerator, and by fission fragments from a 252Cf source (79.4 and 103.8 MeV), after a chemical etching with a 6.25M KOH solution, or with a 6.25M KOH solution with 20% methanol, both solutions at 60±1°C. As an example, the nitrogen ions deposit approximately 1 keV/nm in the form of ionization and excitation at the surface of PET, as calculated using the SRIM code. The fission fragments deposit up to 9 keV/nm at the surface, in both cases generating sufficient free radicals to initiate the track formation process. However, 5 MeV alpha particles, typical of radon (222Rn) emissions, deposit only 0.12 keV/nm, do not present tracks after the chemical etching process. This valuable information could be very useful for further studies of new materials in nuclear track methodology.

  3. Mechanism of microtubule-facilitated "fast track" nuclear import.

    PubMed

    Roth, Daniela Martino; Moseley, Gregory W; Pouton, Colin W; Jans, David A

    2011-04-22

    Although the microtubule (MT) cytoskeleton has been shown to facilitate nuclear import of specific cancer-regulatory proteins including p53, retinoblastoma protein, and parathyroid hormone-related protein (PTHrP), the MT association sequences (MTASs) responsible and the nature of the interplay between MT-dependent and conventional importin (IMP)-dependent nuclear translocation are unknown. Here we used site-directed mutagenesis, live cell imaging, and direct IMP and MT binding assays to map the MTAS of PTHrP for the first time, finding that it is within a short modular region (residues 82-108) that overlaps with the IMPβ1-recognized nuclear localization signal (residues 66-108) of PTHrP. Importantly, fluorescence recovery after photobleaching experiments indicated that disruption of the MT network or mutation of the MTAS of PTHrP decreases the rate of nuclear import by 2-fold. Moreover, MTAS functions depend on mutual exclusivity of binding of PTHrP to MTs and IMPβ1 such that, following MT-dependent trafficking toward the nucleus, perinuclear PTHrP can be displaced from MTs by IMPβ1 prior to import into the nucleus. This is the first molecular definition of an MTAS that facilitates protein nuclear import as well as the first delineation of the mechanism whereby cargo is transferred directly from the cytoskeleton to the cellular nuclear import apparatus. The results have broad significance with respect to fundamental processes regulating cell physiology/transformation.

  4. Polymer microfilters with nanostructured surfaces for the culture of cancer cells

    SciTech Connect

    Makarova, Olga V; Adams, Daniel; Divan, Ralu; Rosenmann, Daniel; Zhu, Peixuan; Li, Shuhong; Amstutz, Platte; Tang, Cha-Mei

    2016-09-01

    There is a critical need to improve the accuracy of drug screening and testing through the development of in vitro culture systems that more effectively mimic the in vivo environment. Surface topographical features on the nanoscale level, in short nanotopography, effect the cell growth patterns, and hence affect cell function in culture. We report the preliminary results on the fabrication, and subsequent cellular growth, of nanoscale surface topography on polymer microfilters using cell lines as a precursor to circulating tumor cells (CTCs). To create various nanoscale features on the microfilter surface, we used reactive ion etching (RIE) with and without an etching mask. An anodized aluminum oxide (AAO) membrane fabricated directly on the polymer surface served as an etching mask. Polymer filters with a variety of modified surfaces were used to compare the effects on the culture of cancer cell lines in blank culture wells, with untreated microfilters or with RIE-treated microfilters. We then report the differences of cell shape, phenotype and growth patterns of bladder and glioblastoma cancer cell lines after isolation on the various types of material modifications. Our data suggest that RIE modified polymer filters can isolate model cell lines while retaining ell viability, and that the RIE filter modification allows T24 monolayering cells to proliferate as a structured cluster. Copyright 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Polymer microfilters with nanostructured surfaces for the culture of circulating cancer cells.

    PubMed

    Makarova, Olga V; Adams, Daniel L; Divan, Ralu; Rosenmann, Daniel; Zhu, Peixuan; Li, Shuhong; Amstutz, Platte; Tang, Cha-Mei

    2016-09-01

    There is a critical need to improve the accuracy of drug screening and testing through the development of in vitro culture systems that more effectively mimic the in vivo environment. Surface topographical features on the nanoscale level, in short nanotopography, effect the cell growth patterns, and hence affect cell function in culture. We report the preliminary results on the fabrication, and subsequent cellular growth, of nanoscale surface topography on polymer microfilters using cell lines as a precursor to circulating tumor cells (CTCs). To create various nanoscale features on the microfilter surface, we used reactive ion etching (RIE) with and without an etching mask. An anodized aluminum oxide (AAO) membrane fabricated directly on the polymer surface served as an etching mask. Polymer filters with a variety of modified surfaces were used to compare the effects on the culture of cancer cell lines in blank culture wells, with untreated microfilters or with RIE-treated microfilters. We then report the differences of cell shape, phenotype and growth patterns of bladder and glioblastoma cancer cell lines after isolation on the various types of material modifications. Our data suggest that RIE modified polymer filters can isolate model cell lines while retaining ell viability, and that the RIE filter modification allows T24 monolayering cells to proliferate as a structured cluster. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  6. A cancer detection platform which measures telomerase activity from live circulating tumor cells captured on microfilter

    PubMed Central

    Xu, Tong; Lu, Bo; Tai, Yu-Chong; Goldkorn, Amir

    2010-01-01

    Circulating tumor cells (CTCs) quantified in cancer patients’ blood can predict disease outcome and response to therapy. However, the CTC analysis platforms commonly used cannot capture live CTCs and only apply to tumors of epithelial origin. To address these limitations, we have developed a novel cancer detection platform which measures telomerase activity from live CTCs captured on a Parylene-C slot microfilter. Using a constant low-pressure delivery system, the new microfilter platform was capable of cell capture from 1 ml of whole blood in less than 5 minutes, achieving 90% capture efficiency, 90% cell viability and 200-fold sample enrichment. Importantly, the captured cells retained normal morphology by scanning electron microscopy and could be readily manipulated, further analyzed, or expanded on or off filter. Telomerase activity – a well-recognized universal cancer marker – was reliably detected by qPCR from as few as 25 cancer cells spiked into 7.5 ml whole blood and captured on microfilter. Moreover, significant telomerase activity elevation also was measured from patient blood samples and from single cancer cells lifted off the microfilter. Live CTC capture and analysis is fast and simple yet highly quantitative, versatile, and applicable to nearly all solid tumor types, making this a highly promising new strategy for cancer detection and characterization. PMID:20663903

  7. Shelf life of pasteurized microfiltered milk containing 2% fat.

    PubMed

    Caplan, Z; Barbano, D M

    2013-01-01

    The goal of this research was to produce homogenized milk containing 2% fat with a refrigerated shelf life of 60 to 90 d using minimum high temperature, short time (HTST) pasteurization in combination with other nonthermal processes. Raw skim milk was microfiltered (MF) using a Tetra Alcross MFS-7 pilot plant (Tetra Pak International SA, Pully, Switzerland) equipped with Membralox ceramic membranes (1.4 μm and surface area of 2.31 m(2); Pall Corp., East Hills, NY). The unpasteurized MF skim permeate and each of 3 different cream sources were blended together to achieve three 2% fat milks. Each milk was homogenized (first stage: 17 MPa, second stage: 3 MPa) and HTST pasteurized (73.8°C for 15s). The pasteurized MF skim permeate and the 3 pasteurized homogenized 2% fat milks (made from different fat sources) were stored at 1.7 and 5.7°C and the standard plate count for each milk was determined weekly over 90 d. When the standard plate count was >20,000 cfu/mL, it was considered the end of shelf life for the purpose of this study. Across 4 replicates, a 4.13 log reduction in bacteria was achieved by MF, and a further 0.53 log reduction was achieved by the combination of MF with HTST pasteurization (73.8°C for 15s), resulting in a 4.66 log reduction in bacteria for the combined process. No containers of MF skim milk that was pasteurized after MF exceeded 20,000 cfu/mL bacteria count during 90 d of storage at 5.7°C. The 3 different approaches used to reduce the initial bacteria and spore count of each cream source used to make the 2% fat milks did not produce any shelf-life advantage over using cold separated raw cream when starting with excellent quality raw whole milk (i.e., low bacteria count). The combination of MF with HTST pasteurization (73.8°C for 15s), combined with filling and packaging that was protected from microbial contamination, achieved a refrigerated shelf life of 60 to 90 d at both 1.7 and 5.7°C for 2% fat milks. Copyright © 2013 American

  8. Tracking of Ions Produced at Near Barrier Energies in Nuclear Reactions

    SciTech Connect

    Shapira, Dan

    2010-01-01

    Examples of detectors, presently in use, for tracking products from nuclear reactions induced by radioactive ion beams are described. A new tracking detector is being designed to study the binary products from reactions induced by heavy neutron-rich radioactive ion beams on heavy neutron-rich target nuclei. The motivation for such studies and the features designed to accomplish this goal will be presented.

  9. Search for anomalons using plastic nuclear track detectors

    NASA Technical Reports Server (NTRS)

    Heinrich, W.; Drechsel, H.; Brechtmann, C.; Dreute, J.

    1985-01-01

    A stack of CR39 track detectors containing Ag foils was exposed to 1.7 GeV/nucleon Fe-56 beam and the anomalous mean free path effect investigated. Neither the whole set of 7517 nor a subset of 2542 interacting fragments produced probably in the Ag target show an effect. By combining the data of this and an earlier experiment we can also exclude an effect for 3219 interacting fragments produced in delta Z=1 collisions.

  10. Experimental set up for the irradiation of biological samples and nuclear track detectors with UV C.

    PubMed

    Portu, Agustina Mariana; Rossini, Andrés Eugenio; Gadan, Mario Alberto; Bernaola, Omar Alberto; Thorp, Silvia Inés; Curotto, Paula; Pozzi, Emiliano César Cayetano; Cabrini, Rómulo Luis; Martin, Gisela Saint

    2016-01-01

    In this work we present a methodology to produce an "imprint" of cells cultivated on a polycarbonate detector by exposure of the detector to UV C radiation. The distribution and concentration of (10)B atoms in tissue samples coming from BNCT (Boron Neutron Capture Therapy) protocols can be determined through the quantification and analysis of the tracks forming its autoradiography image on a nuclear track detector. The location of boron atoms in the cell structure could be known more accurately by the simultaneous observation of the nuclear tracks and the sample image on the detector. A UV C irradiator was constructed. The irradiance was measured along the lamp direction and at different distances. Melanoma cells were cultured on polycarbonate foils, incubated with borophenylalanine, irradiated with thermal neutrons and exposed to UV C radiation. The samples were chemically attacked with a KOH solution. A uniform irradiation field was established to expose the detector foils to UV C light. Cells could be seeded on the polycarbonate surface. Both imprints from cells and nuclear tracks were obtained after chemical etching. It is possible to yield cellular imprints in polycarbonate. The nuclear tracks were mostly present inside the cells, indicating a preferential boron uptake.

  11. Experimental set up for the irradiation of biological samples and nuclear track detectors with UV C

    PubMed Central

    Portu, Agustina Mariana; Rossini, Andrés Eugenio; Gadan, Mario Alberto; Bernaola, Omar Alberto; Thorp, Silvia Inés; Curotto, Paula; Pozzi, Emiliano César Cayetano; Cabrini, Rómulo Luis; Martin, Gisela Saint

    2016-01-01

    Aim In this work we present a methodology to produce an “imprint” of cells cultivated on a polycarbonate detector by exposure of the detector to UV C radiation. Background The distribution and concentration of 10B atoms in tissue samples coming from BNCT (Boron Neutron Capture Therapy) protocols can be determined through the quantification and analysis of the tracks forming its autoradiography image on a nuclear track detector. The location of boron atoms in the cell structure could be known more accurately by the simultaneous observation of the nuclear tracks and the sample image on the detector. Materials and Methods A UV C irradiator was constructed. The irradiance was measured along the lamp direction and at different distances. Melanoma cells were cultured on polycarbonate foils, incubated with borophenylalanine, irradiated with thermal neutrons and exposed to UV C radiation. The samples were chemically attacked with a KOH solution. Results A uniform irradiation field was established to expose the detector foils to UV C light. Cells could be seeded on the polycarbonate surface. Both imprints from cells and nuclear tracks were obtained after chemical etching. Conclusions It is possible to yield cellular imprints in polycarbonate. The nuclear tracks were mostly present inside the cells, indicating a preferential boron uptake. PMID:26933396

  12. Atomic force microscopy methods for the analysis of high-LET tracks in CR-39 plastic nuclear track detector

    NASA Astrophysics Data System (ADS)

    Johnson, Carl E., Jr.

    Scope and Method of Study. Proton- and neutron-induced target fragmentation reactions generate short-range (˜1-10 mum), high-linear energy transfer (LET) heavy nuclear recoil (HNR) particles that contribute to total radiation dose deposited in healthy tissue in patients undergoing proton cancer therapy and to astronauts during spaceflight. Conventional detection using CR-39 plastic nuclear track detector (PNTD) that has been chemically etched for analysis by standard visible light microscopy fails because the required bulk etch, B ≈ 40 mum removes short-range tracks. We have developed a method based on Atomic Force Microscopy (AFM) to directly measure HNR particle tracks in CR-39 PNTD. Novel algorithms using least squares ellipse fitting and estimation of fitting in an iterative process were developed to enable the analysis of nuclear tracks in AFM data. In irradiations conducted at the Loma Linda University Medical Center (LLUMC) Proton Therapy Facility and the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL), targets of varying composition, including a number of elemental targets of high Z, were exposed in contact with layers of CR-39 PNTD to beams of 60 MeV, 230 MeV, and 1 GeV protons at doses between 2 and 10 Gy. Chemical etching of the CR-39 PNTD was performed under standard conditions (50°C, 6.25 N NaOH) for 2-4 hours (removed layer B = 0.5-1.0 mum). Findings and Conclusions. The use of a short duration chemical etch yielded densities of secondary tracks of 105-10 6 cm-2 using the analysis methods presented in this work for accelerator-based experiments. LET spectra were obtained with good statistics between 200 and 1500 keV/mum and the results were consistent with nonelastic nuclear cross sections. Absorbed dose measurements were also completed for selected detectors, ˜7 x 10-10 Gy ion -1 was measured for 230 MeV protons. Additionally our data are consistent with an isotropic HNR particle production mechanism. The semi

  13. Measurements of alpha particle energy using nuclear tracks in solids methodology.

    PubMed

    Espinosa, G; Amero, C; Gammage, R B

    2002-01-01

    In this paper we present a method for the measurement of alpha particle energy using polycarbonate materials as nuclear track detectors (NTDs). This method is based on the interaction of the radiation with the solid-state materials, using the relationship between the energy deposited in the material by the ionising particle and the track developed after an established chemical process. The determination of the geometrical parameters of the formed track, such as major axis, minor axis and overall track length, permit determination of the energy of the alpha particle. The track analysis is performed automatically using a digital image system, and the data are processed in a PC with commercial software. In this experiment 148Gd, 238U, 230Th, 239Pu and 244Cm alpha particle emitters were used. The values for alpha particle energy resolution, the linear response to energy, the confidence in the results and the automatisation of the procedure make this method a promising analysis system.

  14. Image processing analysis of nuclear track parameters for CR-39 detector irradiated by thermal neutron

    NASA Astrophysics Data System (ADS)

    Al-Jobouri, Hussain A.; Rajab, Mustafa Y.

    2016-03-01

    CR-39 detector which covered with boric acid (H3Bo3) pellet was irradiated by thermal neutrons from (241Am - 9Be) source with activity 12Ci and neutron flux 105 n. cm-2. s-1. The irradiation times -TD for detector were 4h, 8h, 16h and 24h. Chemical etching solution for detector was sodium hydroxide NaOH, 6.25N with 45 min etching time and 60 C˚ temperature. Images of CR-39 detector after chemical etching were taken from digital camera which connected from optical microscope. MATLAB software version 7.0 was used to image processing. The outputs of image processing of MATLAB software were analyzed and found the following relationships: (a) The irradiation time -TD has behavior linear relationships with following nuclear track parameters: i) total track number - NT ii) maximum track number - MRD (relative to track diameter - DT) at response region range 2.5 µm to 4 µm iii) maximum track number - MD (without depending on track diameter - DT). (b) The irradiation time -TD has behavior logarithmic relationship with maximum track number - MA (without depending on track area - AT). The image processing technique principally track diameter - DT can be take into account to classification of α-particle emitters, In addition to the contribution of these technique in preparation of nano- filters and nano-membrane in nanotechnology fields.

  15. Calibrations of CR39 and Makrofol nuclear track detectors and search for exotic particles

    NASA Astrophysics Data System (ADS)

    Togo, V.

    2003-09-01

    We present the final results of the search for exotic massive particles in the cosmic radiation performed with the MACRO underground experiment. Magnetic monopoles and nuclearites flux upper limits obtained with the CR39 nuclear track subdetector, the scintillation and streamer tube subdetectors are given. Searches at high altitude with the SLIM experiment are in progress.

  16. Development of a Tracking System of Exotic Nuclear Beams for FAIR

    SciTech Connect

    Fernandez, B.; Abou-Haidar, Z.; Alvarez, M. A. G.; Pancin, J.; Drouart, A.; Kebbiri, M.; Riallot, M.

    2010-04-26

    New accelerators like SPIRAL2 (GANIL, France) or FAIR (GSI, Germany) will be soon constructed, and they will be able to produce radioactive ion beams (RIB) with high intensities of current (>=10{sup 6} pps). These beams, at low energy, lower than 20 MeV/n, usually have high emittance, which imposes the use of tracking detectors before the target in order to reconstruct the trajectory of the ions. The group of Nuclear Physics at CNA (Centro Nacional de Aceleradores), is in charge of developing a tracking system for the low energy branch of FAIR (the HISPEC/DESPEC project). A collaboration with CEA-SACLAY was established, with the aim of developing, building and testing low pressure Secondary electron Detectors (SeD). Within this proposal we have projected and constructed a new Nuclear Physics Line in the CNA in order to be able to receive any kind of detector tests and the associated nuclear instruments.

  17. Development of a Tracking System of Exotic Nuclear Beams for FAIR

    NASA Astrophysics Data System (ADS)

    Fernández, B.; Pancin, J.; Abou-Haidar, Z.; Alvarez, M. A. G.; Drouart, A.; Kebbiri, M.; Riallot, M.

    2010-04-01

    New accelerators like SPIRAL2 (GANIL, France) or FAIR (GSI, Germany) will be soon constructed, and they will be able to produce radioactive ion beams (RIB) with high intensities of current (⩾106 pps). These beams, at low energy, lower than 20 MeV/n, usually have high emittance, which imposes the use of tracking detectors before the target in order to reconstruct the trajectory of the ions. The group of Nuclear Physics at CNA (Centro Nacional de Aceleradores), is in charge of developing a tracking system for the low energy branch of FAIR (the HISPEC/DESPEC project). A collaboration with CEA-SACLAY was established, with the aim of developing, building and testing low pressure Secondary electron Detectors (SeD). Within this proposal we have projected and constructed a new Nuclear Physics Line in the CNA in order to be able to receive any kind of detector tests and the associated nuclear instruments.

  18. Electron recombination in low-energy nuclear recoils tracks in liquid argon

    NASA Astrophysics Data System (ADS)

    Wojcik, M.

    2016-02-01

    This paper presents an analysis of electron-ion recombination processes in ionization tracks of recoiled atoms in liquid argon (LAr) detectors. The analysis is based on the results of computer simulations which use realistic models of electron transport and reactions. The calculations reproduce the recent experimental results of the ionization yield from 6.7 keV nuclear recoils in LAr. The statistical distribution of the number of electrons that escape recombination is found to deviate from the binomial distribution, and estimates of recombination fluctuations for nuclear recoils tracks are obtained. A study of the recombination kinetics shows that a significant part of electrons undergo very fast static recombination, an effect that may be responsible for the weak drift-field dependence of the ionization yield from nuclear recoils in some noble liquids. The obtained results can be useful in the search for hypothetical dark matter particles and in other studies that involve detection of recoiled nuclei.

  19. Fast neutrons detection in CR-39 and DAM-ADC nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Abdalla, A. M.; Ashraf, O.; Rammah, Y. S.; Ashry, A. H.; Eisa, M.; Tsuruta, T.

    2015-03-01

    Fast detection of neutrons in CR-39 and DAM-ADC nuclear track detectors were investigated using new etching conditions. The neutron irradiation is performed using a 5 mCi Am-Be source present at the National Institute of Standards (NIS) of Egypt. Using the new etching condition, irradiated CR-39 samples were etched for 4 h and DAM-ADC samples for 80 min. Suitable analyzing software has been used to analyze experimental data.The dependence of neutrons track density on the neutrons fluence is investigated. When etched under optimum conditions, the relationship between track density and fluence is determined which is found to be linear. Detection efficiency has been represented for both SSNTDs and found to be constant with fluence, which reflects the importance of using CR-39 and DAM-ADC detectors in the field of neutron dosimetry. Linear relationship between track density and effective dose is determined.

  20. Etching characteristic studies for the detection of alpha particles in DAM-ADC nuclear track detector

    NASA Astrophysics Data System (ADS)

    El-Samman, H.; Ashry, A. H.; Arafa, W.; Abou-leila, M.; Abdalla, A. M.; Tsuruta, T.

    2014-09-01

    This study reports the characteristic studies for the detection of alpha particles in DAM-ADC nuclear track detector. Several important parameters that control the track formation such as, the bulk etch rate (VB), track etching rate (VT), dependence of VB and VT on etching concentration and temperature have been extensively studied. The activation energy (Eb) of the bulk etching rate for the DAM-ADC sheets has been calculated, the dependence of etching efficiency and sensitivity upon etchant concentrations and temperature has been investigated, registration efficiency of DAM-ADC detector etched at the optimum etching condition has been examined. The detailed studied results presented in this study provide various useful information about the mechanism of track formation in polymers.

  1. Fabrication and characterization of a microporous polymeric micro-filter for isolation of Cryptosporidium parvum oocysts

    NASA Astrophysics Data System (ADS)

    Ebrahimi Warkiani, Majid; Lou, Chao-Ping; Gong, Hai-Qing

    2011-03-01

    A rapid and effective method to concentrate Cryptosporidium parvum oocysts present in large volumes of drinking water into smaller volumes is critical for accurate detection and quantification of C. parvum oocysts from drinking water. Filtration-based concentration techniques have been widely used to recover C. parvum oocysts into a small volume for downstream analysis. We present a rapid method for fabrication of a polymeric micro-filter with ordered pores and a smooth surface using UV lithography and MEMS technology. To support the filter membrane, we also developed a technique for integrated fabrication of a support mesh. We demonstrated that the filter is able to isolate the oocysts which can be further detected using fluorescent techniques. Sample loading and back-flushing using the micro-filter resulted in 95-99% recovery with a concentration ratio above 2000 of the spiked C. parvum oocysts, which showed significantly improved performance compared with current commercial filters.

  2. Nuclear Track Detector Characterization via Alpha-Spectrometry for Radioprotection Use

    SciTech Connect

    Morelli, D.; Imme, G.; Catalano, R.; Aranzulla, M.; Tazzer, A. L. Rosselli; Mangano, G.

    2011-12-13

    Solid Nuclear Track Detectors (SNTDs), CR-39 type, are usually adopted to monitor radon gas concentrations. In order to characterize the detectors according to track geometrical parameters, detectors were irradiated inside a vacuum chamber by alpha particles at twelve energy values, obtained by different Mylar foils in front of a {sup 241}Am source. The alpha energy values were verified using a Si detector. After the exposure to the alpha particles, the detectors were chemically etched to enlarge the tracks, which were then analyzed by means of a semiautomatic system composed of an optical microscope equipped with a CCD camera connected to a personal computer to store images. A suitable routine analyzed the track parameters: major and minor axis length and mean grey level, allowing us to differentiate tracks according to the incident alpha energy and then to individuate the discrimination factors for radon alpha tracks. The combined use of geometrical and optical parameters allows one to overcome the ambiguity in the alpha energy determination due to the non-monotonicity of each parameter versus energy. After track parameter determination, a calibration procedure was performed by means of a radon chamber. The calibration was verified through an inter-comparing survey.

  3. RADON AND PROGENY ALPHA-PARTICLE ENERGY ANALYSIS USING NUCLEAR TRACK METHODOLOGY

    SciTech Connect

    Espinosa Garcia, Guillermo; Golzarri y Moreno, Dr. Jose Ignacio; Bogard, James S

    2008-01-01

    A preliminary procedure for alpha energy analysis of radon and progeny using Nuclear Track Methodology (NTM) is described in this paper. The method is based on the relationship between alpha-particle energies deposited in polycarbonate material (CR-39) and the track size developed after a well-established chemical etching process. Track geometry, defined by parameters such as major or minor diameters, track area and overall track length, is shown to correlate with alpha-particle energy over the range 6.00 MeV (218Po) to 7.69 MeV (214Po). Track features are measured and the data analyzed automatically using a digital imaging system and commercial PC software. Examination of particle track diameters in CR-39 exposed to environmental radon reveals a multi-modal distribution. Locations of the maxima in this distribution are highly correlated with alpha particle energies of radon daughters, and the distributions are sufficiently resolved to identify the radioisotopes. This method can be useful for estimating the radiation dose from indoor exposure to radon and its progeny.

  4. Nuclear Track Detector Characterization via Alpha-Spectrometry for Radioprotection Use

    NASA Astrophysics Data System (ADS)

    Morelli, D.; Immè, G.; Aranzulla, M.; Tazzer, A. L. Rosselli; Catalano, R.; Mangano, G.

    2011-12-01

    Solid Nuclear Track Detectors (SNTDs), CR-39 type, are usually adopted to monitor radon gas concentrations. In order to characterize the detectors according to track geometrical parameters, detectors were irradiated inside a vacuum chamber by alpha particles at twelve energy values, obtained by different Mylar foils in front of a 241Am source. The alpha energy values were verified using a Si detector. After the exposure to the alpha particles, the detectors were chemically etched to enlarge the tracks, which were then analyzed by means of a semiautomatic system composed of an optical microscope equipped with a CCD camera connected to a personal computer to store images. A suitable routine analyzed the track parameters: major and minor axis length and mean grey level, allowing us to differentiate tracks according to the incident alpha energy and then to individuate the discrimination factors for radon alpha tracks. The combined use of geometrical and optical parameters allows one to overcome the ambiguity in the alpha energy determination due to the non-monotonicity of each parameter versus energy. After track parameter determination, a calibration procedure was performed by means of a radon chamber. The calibration was verified through an inter-comparing survey.

  5. Neutron detection of the Triga Mark III reactor, using nuclear track methodology

    SciTech Connect

    Espinosa, G. Golzarri, J. I.; Raya-Arredondo, R.; Cruz-Galindo, S.; Sajo-Bohus, L.

    2015-07-23

    Nuclear Track Methodology (NTM), based on the neutron-proton interaction is one often employed alternative for neutron detection. In this paper we apply NTM to determine the Triga Mark III reactor operating power and neutron flux. The facility nuclear core, loaded with 85 Highly Enriched Uranium as fuel with control rods in a demineralized water pool, provide a neutron flux around 2 × 10{sup 12} n cm{sup −2} s{sup −1}, at the irradiation channel TO-2. The neutron field is measured at this channel, using Landauer{sup ®} PADC as neutron detection material, covered by 3 mm Plexiglas{sup ®} as converter. After exposure, plastic detectors were chemically etched to make observable the formed latent tracks induced by proton recoils. The track density was determined by a custom made Digital Image Analysis System. The resulting average nuclear track density shows a direct proportionality response for reactor power in the range 0.1-7 kW. We indicate several advantages of the technique including the possibility to calibrate the neutron flux density measured at low reactor power.

  6. Reduced Noise UV Enhancement of Etch Rates for Nuclear Tracks in CR-39

    NASA Astrophysics Data System (ADS)

    Sheets, Rebecca; Clarkson, David; Ume, Rubab; Regan, Sean; Sangster, Craig; Padalino, Stephen; McLean, James

    2016-10-01

    The use of CR-39 plastic as a Solid State Nuclear Track Detector is an effective technique for obtaining data in high-energy particle experiments including inertial confinement fusion. To reveal particle tracks after irradiation, CR-39 is chemically etched in NaOH at 80°C for 6 hours, producing micron-scale signal pits at the nuclear track sites. Using CR-39 irradiated with 5.4 MeV alpha particles and 1.0 MeV protons, we show that exposing the CR-39 to high intensity UV light before etching, with wavelengths between 240 nm and 350 nm, speeds the etch process. Elevated temperatures during UV exposure amplifies this effect, with etch rates up to 50% greater than unprocessed conditions. CR-39 pieces exposed to UV light and heat can also exhibit heightened levels of etch-induced noise (surface features not caused by nuclear particles). By illuminating the CR-39 from the side opposite to the tracks, a similar level of etch enhancement was obtained with little to no noise. The effective wavelength range is reduced, due to strong attenuation of shorter wavelengths. Funded in part by a LLE contract through the DOE.

  7. Isolation of plasma from whole blood using planar microfilters for lab-on-a-chip applications.

    PubMed

    Crowley, Timothy A; Pizziconi, Vincent

    2005-09-01

    Researchers are actively developing devices for the microanalysis of complex fluids, such as blood. These devices have the potential to revolutionize biological analysis in a manner parallel to the computer chip by providing very high throughput screening of complex samples and massively parallel bioanalytical capabilities. A necessary step performed in clinical chemistry is the isolation of plasma from whole blood, and effective sample preparation techniques are needed for the development of miniaturized clinical diagnostic devices. This study demonstrates the use of passive, operating entirely on capillary action, transverse-flow microfilter devices for the microfluidic isolation of plasma from whole blood. Using these planar microfilters, blood can be controllably fractionated with minimal cell lysis. A characterization of the device performance reveals that plasma filter flux is dependent upon the wall shear rate of blood in the filtration channel, and this result is consistent with macroscale blood filtration using microporous membranes. Also, an innovative microfluidic layout is demonstrated that extends device operation time via capillary action from seconds to minutes. Efficiency of these microfilters is approximately three times higher than the separation efficiencies predicted for microporous membranes under similar conditions. As such, the application of the microscale blood filtration designs used in this study may have broad implications in the design of lab-on-a-chip devices, as well as the field of separation science.

  8. Evaluation of a low-cost automatic counting system for nuclear track detectors.

    PubMed

    Wong, C F; Wong, H W; Tsang, P W

    1991-03-01

    This paper describes a low-cost automatic counting system for recognising and counting microscopic track holes in plastic nuclear track detectors. The hardware includes an Olympus BH2 microscope, (manufactured by the Olympus Optical Company, Japan) a Philips resistive gate sensor (RGS) board, (manufactured by the Philips Company, Netherlands) a frame-grabber board and an IBM PC compatible. The RGS board acts like a camera, sending analog video signals of the microscope's field image to the frame-grabber, which produces a digital image with a resolution of 256 x 256 pixels and 128 grey levels in about 20 ms. This is then stored in either one of two 64K on-board RAMs for processing by the PC. The software is menu-driven and allows image grabbing, saving, loading and processing. The image processing can be divided into three parts namely: segmentation, speckle elimination and the removal of ill-formed track holes. In this paper we will present the results of testing the system with sample images obtained from CR-39 plastic nuclear track detectors. The limitations of the system for counting track holes on these detectors will be discussed.

  9. Measuring Human Performance in Simulated Nuclear Power Plant Control Rooms Using Eye Tracking

    SciTech Connect

    Kovesdi, Casey Robert; Rice, Brandon Charles; Bower, Gordon Ross; Spielman, Zachary Alexander; Hill, Rachael Ann; LeBlanc, Katya Lee

    2015-11-01

    Control room modernization will be an important part of life extension for the existing light water reactor fleet. As part of modernization efforts, personnel will need to gain a full understanding of how control room technologies affect performance of human operators. Recent advances in technology enables the use of eye tracking technology to continuously measure an operator’s eye movement, which correlates with a variety of human performance constructs such as situation awareness and workload. This report describes eye tracking metrics in the context of how they will be used in nuclear power plant control room simulator studies.

  10. Thoron activity level and radon measurement by a nuclear track detector.

    PubMed

    Planinić, J; Faj, Z; Vuković, B

    1993-03-01

    Radon activity concentrations in the air were measured with LR-115 nuclear track detectors at three locations in Osijek. The respective equilibrium factors and the effective dose equivalents were determined. Indoor concentrations were from 9.8 to 58.2 Bq m-3 and relative errors of the track etching method were near 19 per cent. The indoor alpha potential energy of the radon and thoron progenies was measured with an ISD detector. Independent measurements, performed with a Radhome semiconductor detector, showed that the indoor thoron concentration was nearly 20 per cent of the radon one.

  11. Image processing analysis of nuclear track parameters for CR-39 detector irradiated by thermal neutron

    SciTech Connect

    Al-Jobouri, Hussain A. Rajab, Mustafa Y.

    2016-03-25

    CR-39 detector which covered with boric acid (H{sub 3}Bo{sub 3}) pellet was irradiated by thermal neutrons from ({sup 241}Am - {sup 9}Be) source with activity 12Ci and neutron flux 10{sup 5} n. cm{sup −2}. s{sup −1}. The irradiation times -T{sub D} for detector were 4h, 8h, 16h and 24h. Chemical etching solution for detector was sodium hydroxide NaOH, 6.25N with 45 min etching time and 60 C° temperature. Images of CR-39 detector after chemical etching were taken from digital camera which connected from optical microscope. MATLAB software version 7.0 was used to image processing. The outputs of image processing of MATLAB software were analyzed and found the following relationships: (a) The irradiation time -T{sub D} has behavior linear relationships with following nuclear track parameters: i) total track number - N{sub T} ii) maximum track number - MRD (relative to track diameter - D{sub T}) at response region range 2.5 µm to 4 µm iii) maximum track number - M{sub D} (without depending on track diameter - D{sub T}). (b) The irradiation time -T{sub D} has behavior logarithmic relationship with maximum track number - M{sub A} (without depending on track area - A{sub T}). The image processing technique principally track diameter - D{sub T} can be take into account to classification of α-particle emitters, In addition to the contribution of these technique in preparation of nano- filters and nano-membrane in nanotechnology fields.

  12. ATMS_Phase_II: a standalone code for counting non-overlapping high-density nuclear tracks

    NASA Astrophysics Data System (ADS)

    Khayat, Omid

    2014-02-01

    In this paper we focus on counting and density measurements of non-overlapping high-density nuclear track images. This paper is a continuum of another paper of the author introducing ATMS software which has been particularly developed for overlapping nuclear tracks. Here, as the second phase of the ATMS software, a hybrid algorithm is presented for counting the tracks according to user parameter initialization, template inserting and correlation estimation to initially detect nuclear track candidates, then to evaluate geometrical and contextual features of track candidates and finally a decision-making process according to the user's sensitivity considerations. The presented hybrid algorithm is verified and validated by a database containing 100 randomly selected Alpha track images captured from the surface of CR-39 polycarbonate detectors irradiated by environmental Alpha particles emitted from Rn-222 near a copper mine around Anarak city.

  13. Toward an Automated Analysis of Slow Ions in Nuclear Track Emulsion

    NASA Astrophysics Data System (ADS)

    Mamatkulov, K. Z.; Kattabekov, R. R.; Ambrozova, I.; Artemenkov, D. A.; Bradnova, V.; Kamanin, D. V.; Majling, L.; Marey, A.; Ploc, O.; Rusakova, V. V.; Stanoeva, R.; Turek, K.; Zaitsev, A. A.; Zarubin, P. I.; Zarubina, I. G.

    Application of the nuclear track emulsion technique (NTE) in radioactivity and nuclear fission studies is discussed. It is suggested to use a HSP-1000 automated microscope for searching for a collinear cluster tri-partition of heavy nuclei implanted in NTE. Calibrations of α-particles and ion ranges in a novel NTE are carried out. Surface exposures of NTE samples to a 252Cf source started. Planar events containing fragments and long-range α-particles as well as fragment triples only are studied. NTE samples are calibrated by ions Kr and Xe of energy of 1.2 and 3 A MeV.

  14. Solid State Track Recorder applications in United States nuclear reactor energy programs

    SciTech Connect

    Gold, R.; Ruddy, F.H.; Roberts, J.H.

    1980-01-01

    The domain of Solid State Track Recorder (SSTR) applications in United States nuclear reactor energy programs extends from the harsh high temperature environments found in high power reactor cores to very low flux environments arising in out-of-core locations, critical assemblies, or away from reactors (AFR) experiments. The neutron energy region arising in these applications is very broad, covering more than eight orders of magnitude from thermal up to fusion energies. The range of neutron flux/fluence intensity is even greater, extending over more than thirteen orders of magnitude. As a consequence, use of a variety of SSTR is entailed in US nuclear reactor energy programs.

  15. Thermoluminescence and nuclear particle tracks in ALHA-81005 Evidence for a brief transit time

    NASA Astrophysics Data System (ADS)

    Sutton, S. R.; Crozaz, G.

    1983-09-01

    Thermoluminescence and nuclear particle track measurements were made on the Antarctic meteorite ALHA-81005. No nuclear particle tracks were found in lithic fragments indicating that the clast material never resided at the very surface of the parent body. The unusually low natural thermoluminescence of this material is interpreted as being due to a combination of anomalous fading and thermal decay. The thermal decay could be due to very long terrestrial age or heating either during atmospheric entry, in a near sun orbit or during a parent body impact event. Impact heating is considered the more likely of these possibilities for this meteorite. If the impact heating interpretation is correct the thermoluminescence data constrains the space exposure time of the object to be less than 2,500 years. Such a brief earth transit time is consistent with a lunar origin for this meteorite.

  16. Application of nuclear particle tracks: A scanning x-ray microscope

    SciTech Connect

    Ebert, P.J.

    1991-09-30

    The scanning x-ray microscope (SXM) is a short-wavelength analog of a near-field optical-scanning microscope, promising spatial resolution of {approximately}100{angstrom} up to {approximately}5 keV x-ray energy. A portion of a synchrotron x-ray beam streams through an etched nuclear particle track in an opaque membrane and impinges on an object within the narrow stream. Scattered or transmitted x-rays are detected with a photon counter. The SXM is feasible because a useful number of synchrotron x-rays, even from a bend magnet, will stream through a small diameter pore. The properties and limitations of the SXM are discussed together with other submicroscopic applications of nuclear particle tracks. 14 refs., 8 figs., 1 tab.

  17. A novel Al 2O 3 fluorescent nuclear track detector for heavy charged particles and neutrons

    NASA Astrophysics Data System (ADS)

    Akselrod, G. M.; Akselrod, M. S.; Benton, E. R.; Yasuda, N.

    2006-06-01

    A novel Al2O3 fluorescent nuclear track detector (FNTD), recently developed by Landauer, Inc., has demonstrated sensitivity and functionality superior to that of existing nuclear track detectors. The FNTD is based on single crystals of aluminum oxide doped with carbon and magnesium, and having aggregate oxygen vacancy defects (Al2O3:C,Mg). Radiation-induced color centers in the new material have an absorption band at 620 nm and produce fluorescence at 750 nm with a high quantum yield and a short, 75 ± 5 ns, fluorescence lifetime. Non-destructive readout of the detector is performed using a confocal fluorescence microscope. Scanning of the three-dimensional spatial distribution of fluorescence intensity along the track of a heavy charged particle (HCP) permits reconstruction of particle trajectories through the crystal and the LET can be determined as a function of distance along the trajectory based on the fluorescence intensity. Major advantages of Al2O3:C,Mg FNTD over conventionally processed CR-39 plastic nuclear track detector include superior spatial resolution, a wider range of LET sensitivity, no need for post-irradiation chemical processing of the detector and the capability to anneal and reuse the detector. Preliminary experiments have demonstrated that the material possesses a low-LET threshold of <1 keV/μm, does not saturate at LET in water as high as 1800 keV/μm, and is capable of irradiation to fluences in excess of 106 cm-2 without saturation (track overlap).

  18. A simple apparatus for quick qualitative analysis of CR39 nuclear track detectors

    SciTech Connect

    Gautier, D. C.; Kline, J. L.; Flippo, K. A.; Gaillard, S. A.; Letzring, S. A.; Hegelich, B. M.

    2008-10-15

    Quantifying the ion pits in Columbia Resin 39 (CR39) nuclear track detector from Thomson parabolas is a time consuming and tedious process using conventional microscope based techniques. A simple inventive apparatus for fast screening and qualitative analysis of CR39 detectors has been developed, enabling efficient selection of data for a more detailed analysis. The system consists simply of a green He-Ne laser and a high-resolution digital single-lens reflex camera. The laser illuminates the edge of the CR39 at grazing incidence and couples into the plastic, acting as a light pipe. Subsequently, the laser illuminates all ion tracks on the surface. A high-resolution digital camera is used to photograph the scattered light from the ion tracks, enabling one to quickly determine charge states and energies measured by the Thomson parabola.

  19. The response of CR-39 nuclear track detector to 1-9 MeV protons

    DOE PAGES

    Sinenian, N.; Rosenberg, M. J.; Manuel, M.; ...

    2011-10-28

    The response of CR-39 nuclear track detector (TasTrak®) to protons in the energy range of 0.92-9.28 MeV has been studied. Previous studies of the CR-39 response to protons have been extended by examining the piece-to-piece variability in addition to the effects of etch time and etchant temperature; it is shown that the shape of the CR-39 response curve to protons can vary from piece-to-piece. The effects due to the age of CR-39 have also been studied using 5.5 MeV alpha particles over a 5-year period. Track diameters were found to degrade with the age of the CR-39 itself rather thanmore » the age of the tracks, consistent with previous studies utilizing different CR-39 over shorter time periods.« less

  20. A simple apparatus for quick qualitative analysis of CR39 nuclear track detectors.

    PubMed

    Gautier, D C; Kline, J L; Flippo, K A; Gaillard, S A; Letzring, S A; Hegelich, B M

    2008-10-01

    Quantifying the ion pits in Columbia Resin 39 (CR39) nuclear track detector from Thomson parabolas is a time consuming and tedious process using conventional microscope based techniques. A simple inventive apparatus for fast screening and qualitative analysis of CR39 detectors has been developed, enabling efficient selection of data for a more detailed analysis. The system consists simply of a green He-Ne laser and a high-resolution digital single-lens reflex camera. The laser illuminates the edge of the CR39 at grazing incidence and couples into the plastic, acting as a light pipe. Subsequently, the laser illuminates all ion tracks on the surface. A high-resolution digital camera is used to photograph the scattered light from the ion tracks, enabling one to quickly determine charge states and energies measured by the Thomson parabola.

  1. The response of CR-39 nuclear track detector to 1-9 MeV protons

    SciTech Connect

    Sinenian, N.; Rosenberg, M. J.; Manuel, M.; McDuffee, S. C.; Casey, D. T.; Zylstra, A. B.; Rinderknecht, H. G.; Johnson, M. Gatu; Seguin, F. H.; Frenje, J. A.; Li, C. K.; Petrasso, R. D.

    2011-10-28

    The response of CR-39 nuclear track detector (TasTrak®) to protons in the energy range of 0.92-9.28 MeV has been studied. Previous studies of the CR-39 response to protons have been extended by examining the piece-to-piece variability in addition to the effects of etch time and etchant temperature; it is shown that the shape of the CR-39 response curve to protons can vary from piece-to-piece. The effects due to the age of CR-39 have also been studied using 5.5 MeV alpha particles over a 5-year period. Track diameters were found to degrade with the age of the CR-39 itself rather than the age of the tracks, consistent with previous studies utilizing different CR-39 over shorter time periods.

  2. Automated scanning of plastic nuclear track detectors using the Minnesota star scanner

    NASA Technical Reports Server (NTRS)

    Fink, P. J.; Waddington, C. J.

    1986-01-01

    The problems found in an attempt to adapt an automated scanner of astronomical plates, the Minnesota Automated Dual Plate Scanner (APS), to locating and measuring the etch pits produced by ionizing particles in plastic nuclear track detectors (CR-39) are described. A visual study of these pits was made to determine the errors introduced in determining positions and shapes. Measurements made under a low power microscope were compared with those from the APS.

  3. Fast detection of alpha particles in DAM-ADC nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Rammah, Y. S.; Ashraf, O.; Abdalla, A. M.; Eisa, M.; Ashry, A. H.; Tsuruta, T.

    2015-02-01

    Fast detection of alpha particles in DAM-ADC nuclear track detectors using a new chemical etchant was investigated. 252Cf and 241Am sources were used for irradiating samples of DAM-ADC SSNTDs with fission fragments and alpha particles in air at normal temperature and pressure. A series of experimental chemical etching are carried out using new etching solution (8 ml of 10 N NaOH+ 1 ml CH3OH) at 60 °C to detect alpha particle in short time in DAM-ADC detectors. Suitable analyzing software has been used to analyze experimental data. From fission and alpha track diameters, the value of bulk etching rate is equal to 8.52 μm/h. Both of the sensitivity and etching efficiency were found to vary with the amount of methanol in the etching solution and etching time. The DAM-ADC detectors represent the best efficiency applicable in detectors in the entire range of alpha energies (from 1 to 5 MeV). The activation energies of this etchant have been calculated; track activation energy, ET, has been found to be lower than the bulk activation energy, EB, for the DAM-ADC nuclear track detectors. These results are in more agreement with the previous work.

  4. Automated motion correction based on target tracking for dynamic nuclear medicine studies

    NASA Astrophysics Data System (ADS)

    Cao, Xinhua; Tetrault, Tracy; Fahey, Fred; Treves, Ted

    2008-03-01

    Nuclear medicine dynamic studies of kidneys, bladder and stomach are important diagnostic tools. Accurate generation of time-activity curves from regions of interest (ROIs) requires that the patient remains motionless for the duration of the study. This is not always possible since some dynamic studies may last from several minutes to one hour. Several motion correction solutions have been explored. Motion correction using external point sources is inconvenient and not accurate especially when motion results from breathing, organ motion or feeding rather than from body motion alone. Centroid-based motion correction assumes that activity distribution is only inside the single organ (without background) and uniform, but this approach is impractical in most clinical studies. In this paper, we present a novel technique of motion correction that first tracks the organ of interest in a dynamic series then aligns the organ. The implementation algorithm for target tracking-based motion correction consists of image preprocessing, target detection, target positioning, motion estimation and prediction, tracking (new search region generation) and target alignment. The targeted organ is tracked from the first frame to the last one in the dynamic series to generate a moving trajectory of the organ. Motion correction is implemented by aligning the organ ROIs in the image series to the location of the organ in the first image. The proposed method of motion correction has been applied to several dynamic nuclear medicine studies including radionuclide cystography, dynamic renal scintigraphy, diuretic renography and gastric emptying scintigraphy.

  5. A new fast scanning system for the measurement of large angle tracks in nuclear emulsions

    NASA Astrophysics Data System (ADS)

    Alexandrov, A.; Buonaura, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; Di Crescenzo, A.; Di Marco, N.; Galati, G.; Lauria, A.; Montesi, M. C.; Pupilli, F.; Shchedrina, T.; Tioukov, V.; Vladymyrov, M.

    2015-11-01

    Nuclear emulsions have been widely used in particle physics to identify new particles through the observation of their decays thanks to their unique spatial resolution. Nevertheless, before the advent of automatic scanning systems, the emulsion analysis was very demanding in terms of well trained manpower. Due to this reason, they were gradually replaced by electronic detectors, until the '90s, when automatic microscopes started to be developed in Japan and in Europe. Automatic scanning was essential to conceive large scale emulsion-based neutrino experiments like CHORUS, DONUT and OPERA. Standard scanning systems have been initially designed to recognize tracks within a limited angular acceptance (θ lesssim 30°) where θ is the track angle with respect to a line perpendicular to the emulsion plane. In this paper we describe the implementation of a novel fast automatic scanning system aimed at extending the track recognition to the full angular range and improving the present scanning speed. Indeed, nuclear emulsions do not have any intrinsic limit to detect particle direction. Such improvement opens new perspectives to use nuclear emulsions in several fields in addition to large scale neutrino experiments, like muon radiography, medical applications and dark matter directional detection.

  6. Automatic track following system to study double strangeness nuclei in nuclear emulsion exposed to the observable limit

    NASA Astrophysics Data System (ADS)

    Myint Kyaw Soe; Goto, Ryosuke; Mishina, Akihiro; Nakanisi, Yoshiaki; Nakashima, Daisuke; Yoshida, Junya; Nakazawa, Kazuma

    2017-03-01

    An automatic track following system has been successfully developed to follow tracks in nuclear emulsion sheets exposed with beam up to the limit to be observed for the first time. The track followed rate of the system is 99.5% with the assistance of the new techniques. The working speed for a track is less than 1 min through one thick emulsion sheet, whereas it is 15 times faster than that of semiautomatic system with human. The system working for 24 h is applied for the E07 experiment at J-PARC and makes it possible to detect 102 nuclei with double strangeness (S=-2 nuclei) within one year. Regarding analyses to identify nuclear species of S=-2 nuclei, the system shows quite decent job for significant steps such as following tracks emitted to spherical directions from S=-2 nuclei, measurement of lengths of followed tracks, and so on.

  7. Demonstration (DEMO) of Radio Frequency Identification (RFID) system for tracking and monitoring of nuclear materials.

    SciTech Connect

    Tsai, H. C.; Chen, K.; Liu, Y. Y.; Shuler, J.

    2010-01-01

    The US Department of Energy (DOE) [Environmental Management (EM), Office of Packaging and Transportation (EM-45)] Packaging Certification Program (PCP) has developed a radiofrequency identification (RFID) tracking and monitoring system for the management of nuclear materials packages during storage and transportation. The system, developed by the PCP team at Argonne National Laboratory, involves hardware modification, application software development, secured database and web server development, and irradiation experiments. In April 2008, Argonne tested key features of the RFID tracking and monitoring system in a weeklong, 1700 mile (2736 km) demonstration employing 14 empty type B fissile material drums of three designs (models 9975, 9977 and ES-3100) that have been certified for shipment by the DOE and the US Nuclear Regulatory Commission. The demonstration successfully integrated global positioning system (GPS) technology for vehicle tracking, satellite/cellular (general packet radio service, or GPRS) technologies for wireless communication, and active RFID tags with multiple sensors (seal integrity, shock, temperature, humidity and battery status) on drums. In addition, the demonstration integrated geographic information system (GIS) technology with automatic alarm notifications of incidents and generated buffer zone reports for emergency response and management of staged incidents. The demonstration was sponsored by EM and the US National Nuclear Security Administration, with the participation of Argonne, Savannah River and Oak Ridge National Laboratories. Over 50 authorised stakeholders across the country observed the demonstration via secured Internet access. The DOE PCP and national laboratories are working on several RFID system implementation projects at selected DOE sites, as well as continuing device and systems development and widening applications beyond DOE sites and possibly beyond nuclear materials to include other radioactive materials.

  8. Flow rate through microfilters: Influence of the pore size distribution, hydrodynamic interactions, wall slip, and inertia

    NASA Astrophysics Data System (ADS)

    Jensen, Kaare H.; Valente, André X. C. N.; Stone, Howard A.

    2014-05-01

    We examine the fluid mechanics of viscous flow through filters consisting of perforated thin plates. We classify the effects that contribute to the hydraulic resistance of the filter. Classical analyses assume a single pore size and account only for filter thickness. We extend these results to obtain an analytical formula for the pressure drop across the microfilter versus the flow rate that accounts for the non-uniform distribution of pore sizes, the hydrodynamic interactions between the pores given their layout pattern, and wall slip. Further, we discuss inertial effects and their order of scaling.

  9. Tracking patient radiation exposure: challenges to integrating nuclear medicine with other modalities

    PubMed Central

    Mercuri, Mathew; Rehani, Madan M.; Einstein, Andrew J.

    2013-01-01

    The cumulative radiation exposure to the patient from multiple radiological procedures can place some individuals at significantly increased risk for stochastic effects and tissue reactions. Approaches, such as those in the International Atomic Energy Agency’s Smart Card program, have been developed to track cumulative radiation exposures to individuals. These strategies often rely on the availability of structured dose reports, typically found in the DICOM header. Dosimetry information is currently readily available for many individual x-ray based procedures. Nuclear medicine, of which nuclear cardiology constitutes the majority of the radiation burden in the U.S., currently lags behind x-ray based procedures with respect to reporting of radiation dosimetric information. This paper discusses qualitative differences between nuclear medicine and x-ray based procedures, including differences in the radiation source and measurement of its strength, the impact of biokinetics on dosimetry, and the capability of current scanners to record dosimetry information. These differences create challenges in applying monitoring and reporting strategies used in x-ray based procedures to nuclear medicine, and integrating dosimetry information across modalities. A concerted effort by the medical imaging community, dosimetry specialists and manufacturers of imaging equipment is required to develop strategies to improve the reporting of radiation dosimetry data in nuclear medicine. Some ideas on how to address this issue are suggested. PMID:22695788

  10. Nuclear tracks, Sm isotopes and neutron capture effects in the Elephant Morraine shergottite

    NASA Technical Reports Server (NTRS)

    Rajan, R. S.; Lugmair, G.; Tamhane, A. S.; Poupeau, G.

    1986-01-01

    Nuclear track studies, uranium concentration measurements and Sm-isotope studies have been performed on both lithologies A and B of the Elephant Morraine shergottite, EETA 79001. Track studies show that EETA 79001 was a rather small object in space with a preatmospheric radius of 12 + or - 2 cm, corresponding to a preatmospheric mass of 28 + or - 13 kg. Phosphates have U concentrations ranging from 0.3 to 1.3 ppm. There are occasional phosphates with excess fission tracks, possibly produced from neutron-induced fission of U and Th, during the regolith exposure in the shergottite parent body (SPB). Sm-isotope studies, while not showing any clear-cut excess in Sm-150, make it possible to derive meaningful upper limits to thermal neutron fluences of 2 to 3 x 10 to the 15th n/sq cm, during a possible regolith irradiation. These limits are consistent with the track data and also make it possible to derive an upper limit to the neutron exposure age of EETA 79001 of 55 Myr in the SPB regolith.

  11. Nuclear tracks, SM isotopes and neutron capture effects in the Elephant Morraine shergottite

    NASA Astrophysics Data System (ADS)

    Rajan, R. S.; Lugmair, G.; Tamhane, A. S.; Poupeau, G.

    1986-06-01

    Nuclear track studies, uranium concentration measurements and Sm-isotope studies have been performed on both lithologies A and B of the Elephant Morraine shergottite, EETA 79001. Track studies show that EETA 79001 was a rather small object in space with a preatmospheric radius of 12 + or - 2 cm, corresponding to a preatmospheric mass of 28 + or - 13 kg. Phosphates have U concentrations ranging from 0.3 to 1.3 ppm. There are occasional phosphates with excess fission tracks, possibly produced from neutron-induced fission of U and Th, during the regolith exposure in the shergottite parent body (SPB). Sm-isotope studies, while not showing any clear-cut excess in Sm-150, make it possible to derive meaningful upper limits to thermal neutron fluences of 2 to 3 x 10 to the 15th n/sq cm, during a possible regolith irradiation. These limits are consistent with the track data and also make it possible to derive an upper limit to the neutron exposure age of EETA 79001 of 55 Myr in the SPB regolith.

  12. Nuclear tracks, Sm isotopes and neutron capture effects in the Elephant Morraine shergottite

    NASA Technical Reports Server (NTRS)

    Rajan, R. S.; Lugmair, G.; Tamhane, A. S.; Poupeau, G.

    1986-01-01

    Nuclear track studies, uranium concentration measurements and Sm-isotope studies have been performed on both lithologies A and B of the Elephant Morraine shergottite, EETA 79001. Track studies show that EETA 79001 was a rather small object in space with a preatmospheric radius of 12 + or - 2 cm, corresponding to a preatmospheric mass of 28 + or - 13 kg. Phosphates have U concentrations ranging from 0.3 to 1.3 ppm. There are occasional phosphates with excess fission tracks, possibly produced from neutron-induced fission of U and Th, during the regolith exposure in the shergottite parent body (SPB). Sm-isotope studies, while not showing any clear-cut excess in Sm-150, make it possible to derive meaningful upper limits to thermal neutron fluences of 2 to 3 x 10 to the 15th n/sq cm, during a possible regolith irradiation. These limits are consistent with the track data and also make it possible to derive an upper limit to the neutron exposure age of EETA 79001 of 55 Myr in the SPB regolith.

  13. Secondary ion emission dynamics model: A tool for nuclear track analysis

    NASA Astrophysics Data System (ADS)

    Iza, P.; Farenzena, L. S.; Jalowy, T.; Groeneveld, K. O.; da Silveira, E. F.

    2006-04-01

    The initial velocity distribution of secondary ions is employed as a tool to analyze nuclear track formation processes occurring in the picosecond time range. The choice of the secondary ion for such analysis depends on the particular surface region and on the desorption time range of interest: (a) H+ ions are emitted promptly from the impact site, (b) H- desorption occurs delayed and mostly from the impact periphery, (c) emitted molecular ions are accelerated away during tens of picoseconds exclusively from the impact periphery. The model is set up considering the track as two coaxial cylinders, the inner one positively charged and the outer one negatively charged. It takes into account effects due to the track charge image formed by a metallic substrate, the projectile angle of incidence, the variation of the electronic stopping power for projectiles out of the equilibrium-charge regime, and a positive and negative track neutralization whose rates are exponentially decreasing with time. Predictions of the model are presented for ion desorption of LiF bombarded by 1 MeV Ar ions.

  14. Single-sheet identification method of heavy charged particles using solid state nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Zaki, M. F.; Abdel-Naby, A.; Morsy, A. Ahmed

    2007-08-01

    The theoretical and experimental investigations of the penetration of charged particles in matter played a very important role in the development of modern physics. Solid state nuclear track detectors have become one of the most important tools for many branches of science and technology. An attempt has been made to examine the suitability of the single-sheet particle identification technique in CR-39 and CN-85 polycarbonate by plotting track cone length vs. residual range for different heavy ions in these detectors. So, the maximum etchable ranges of heavy ions such as ^{93}Nb, ^{86}Kr and ^{4}He in CR-39 and ^{4}He and ^{132}Xe in CN-85 polycarbonate have been determined. The ranges of these ions in these detectors have also been computed theoretically using the Henke-Benton program. A reasonably good agreement has been observed between the experimentally and theoretically computed values.

  15. A National Tracking Center for Monitoring Shipments of HEU, MOX, and Spent Nuclear Fuel: How do we implement?

    SciTech Connect

    Mark Schanfein

    2009-07-01

    Nuclear material safeguards specialists and instrument developers at US Department of Energy (USDOE) National Laboratories in the United States, sponsored by the National Nuclear Security Administration (NNSA) Office of NA-24, have been developing devices to monitor shipments of UF6 cylinders and other radioactive materials , . Tracking devices are being developed that are capable of monitoring shipments of valuable radioactive materials in real time, using the Global Positioning System (GPS). We envision that such devices will be extremely useful, if not essential, for monitoring the shipment of these important cargoes of nuclear material, including highly-enriched uranium (HEU), mixed plutonium/uranium oxide (MOX), spent nuclear fuel, and, potentially, other large radioactive sources. To ensure nuclear material security and safeguards, it is extremely important to track these materials because they contain so-called “direct-use material” which is material that if diverted and processed could potentially be used to develop clandestine nuclear weapons . Large sources could be used for a dirty bomb also known as a radioactive dispersal device (RDD). For that matter, any interdiction by an adversary regardless of intent demands a rapid response. To make the fullest use of such tracking devices, we propose a National Tracking Center. This paper describes what the attributes of such a center would be and how it could ultimately be the prototype for an International Tracking Center, possibly to be based in Vienna, at the International Atomic Energy Agency (IAEA).

  16. History of the bubble chamber and related active- and internal-target nuclear tracking detectors

    NASA Astrophysics Data System (ADS)

    Becchetti, F. D.

    2015-06-01

    Donald Glaser, 1960 Nobel laureate in Physics, recently passed away (2013), as have many of his colleagues who were involved with the early development of bubble chambers at the University of Michigan. In this paper I will review those early years and the subsequent wide-spread application of active-target (AT) bubble chambers that dominated high-energy physics (HEP) research for over thirty years. Some of the related, but more modern nuclear tracking detectors being used in HEP, neutrino astrophysics and dark-matter searches also will be discussed.

  17. State of Fukushima nuclear fuel debris tracked by Cs137 in cooling water.

    PubMed

    Grambow, B; Mostafavi, M

    2014-11-01

    It is still difficult to assess the risk originating from the radioactivity inventory remaining in the damaged Fukushima nuclear reactors. Here we show that cooling water analyses provide a means to assess source terms for potential future releases. Until now already about 34% of the inventories of (137)Cs of three reactors has been released into water. We found that the release rate of (137)Cs has been constant for 2 years at about 1.8% of the inventory per year indicating ongoing dissolution of the fuel debris. Compared to laboratory studies on spent nuclear fuel behavior in water, (137)Cs release rates are on the higher end, caused by the strong radiation field and oxidant production by water radiolysis and by impacts of accessible grain boundaries. It is concluded that radionuclide analyses in cooling water allow tracking of the conditions of the damaged fuel and the associated risks.

  18. AN APPROACH FOR ENHANCING NUCLEAR MATERIALS TRACKING AND REPORTING IN WASTE

    SciTech Connect

    V. L. LONGMIRE; S. L. SEITZ; B. J. SINKULE

    2001-06-01

    Recent policy from the Department of Energy/Office of Safeguards and Security (DOE/OSS) has identified the need to report nuclear materials in waste in a manner that is consistent with the Department of Energy's Nuclear Materials Information System (NMIS), which uses Form 471 as its official record. NMIS is used to track nuclear material inventories while they are subject to safeguards. This requirement necessitates the reevaluation of existing business practices that are used to track and report these nuclear materials. This paper provides a methodology for applying a systems approach to the evaluation of the flow of nuclear waste materials from a generating facility through to permanent disposal. This methodology can be used to integrate existing systems and leverage data already gathered that support both the waste reporting requirements and the NMIS requirements. In order to consider an active waste reporting system that covers waste management through to final disposal, the requirements for characterization, certification, and transportation for disposal at the Waste Isolation Pilot Plant (WIPP) are used as an example. These requirements are found in the WIPP Waste Acceptance Criteria (WIPP/WAC) and associated requirement documents. This approach will prevent inconsistencies in reported data and address current and future needs. For example, spent fuel (which the U.S. intends to dispose of as high-level waste) has not been viewed as particularly attractive in terms of proliferation in comparison to materials associated with other parts of the nuclear fuel cycle. However, collecting high-level waste (or some types of defense waste) in one location where it will be left for hundreds or thousands of years presents proliferation and safeguards issues that need to be considered as part of a systems evaluation. This paper brings together information on domestic and international safeguards practices and considers the current system of documentation used by the U

  19. Fluorescent nuclear track images of Ag-activated phosphate glass irradiated with photons and heavy charged particles

    NASA Astrophysics Data System (ADS)

    Kurobori, Toshio; Yanagida, Yuka; Kodaira, Satoshi; Shirao, Taichi

    2017-05-01

    In this paper we report about the demonstration of the nuclear track imaging capabilities of Ag-activated phosphate glass. A 375 nm laser and confocal laser scanning microscopy (CLSM) were respectively used for track excitation and detection. Specifically, the blue and orange radiophotoluminescent (RPL) tracks and dose distributions observed after irradiation with soft X-rays, gamma rays and heavy charged particles (HCPs) are examined. In addition, the origins of the reductions in RPL efficiency for high-dose X-ray irradiation and for irradiation with HCPs with high linear energy transfer (LET) values are investigated via a CLSM and a conventional fluorescent reader and discussed.

  20. TESTING OF A FULL-SCALE ROTARY MICROFILTER FOR THE ENHANCED PROCESS FOR RADIONUCLIDES REMOVAL

    SciTech Connect

    Herman, D; David Stefanko, D; Michael Poirier, M; Samuel Fink, S

    2009-01-01

    Savannah River National Laboratory (SRNL) researchers are investigating and developing a rotary microfilter for solid-liquid separation applications in the Department of Energy (DOE) complex. One application involves use in the Enhanced Processes for Radionuclide Removal (EPRR) at the Savannah River Site (SRS). To assess this application, the authors performed rotary filter testing with a full-scale, 25-disk unit manufactured by SpinTek Filtration with 0.5 micron filter media manufactured by Pall Corporation. The filter includes proprietary enhancements by SRNL. The most recent enhancement is replacement of the filter's main shaft seal with a John Crane Type 28LD gas-cooled seal. The feed material was SRS Tank 8F simulated sludge blended with monosodium titanate (MST). Testing examined total insoluble solids concentrations of 0.06 wt % (126 hours of testing) and 5 wt % (82 hours of testing). The following are conclusions from this testing.

  1. 3D microfilter device for viable circulating tumor cell (CTC) enrichment from blood.

    PubMed

    Zheng, Siyang; Lin, Henry K; Lu, Bo; Williams, Anthony; Datar, Ram; Cote, Richard J; Tai, Yu-Chong

    2011-02-01

    Detection of circulating tumor cells has emerged as a promising minimally invasive diagnostic and prognostic tool for patients with metastatic cancers. We report a novel three dimensional microfilter device that can enrich viable circulating tumor cells from blood. This device consists of two layers of parylene membrane with pores and gap precisely defined with photolithography. The positions of the pores are shifted between the top and bottom membranes. The bottom membrane supports captured cells and minimize the stress concentration on cell membrane and sustain cell viability during filtration. Viable cell capture on device was investigated with scanning electron microscopy, confocal microscopy, and immunofluorescent staining using model systems of cultured tumor cells spiked in blood or saline. The paper presents and validates this new 3D microfiltration concept for circulation tumor cell enrichment application. The device provides a highly valuable tool for assessing and characterizing viable enriched circulating tumor cells in both research and clinical settings.

  2. Neutron angular distribution in a plasma focus obtained using nuclear track detectors.

    PubMed

    Castillo-Mejía, F; Herrera, J J E; Rangel, J; Golzarri, J I; Espinosa, G

    2002-01-01

    The dense plasma focus (DPF) is a coaxial plasma gun in which a high-density, high-temperature plasma is obtained in a focused column for a few nanoseconds. When the filling gas is deuterium, neutrons can be obtained from fusion reactions. These are partially due to a beam of deuterons which are accelerated against the background hot plasma by large electric fields originating from plasma instabilities. Due to a beam-target effect, the angular distribution of the neutron emission is anisotropic, peaked in the forward direction along the axis of the gun. The purpose of this work is to illustrate the use of CR-39 nuclear track detectors as a diagnostic tool in the determination of the time-integrated neutron angular distribution. For the case studied in this work, neutron emission is found to have a 70% contribution from isotropic radiation and a 30% contribution from anisotropic radiation.

  3. Copper Nano- and Micro Wires Electrodeposited in Etched Cellulose Nitrate and Makrofol KG Nuclear Track Detector

    NASA Astrophysics Data System (ADS)

    Jooybari, B. Shakeri; Afarideh, H.; Lamehi-Racti, M.; Moghimi, R.; Ghergherehchi, M.

    Cellulose Nitrate and Makrofol KG nuclear track detector foils of 96 μm and 20 μm thicknesses were irradiated with 238U ions (kinetic energy 17.7 MeV/u, fluence 105 ion/cm2) and 208Pd (kinetic energy 14.0MeV/u, fluence 105 ion/cm2), respectively. By etching of damage trail caused by the ion, templates containing conical pore were prepared. By electrochemical deposition of copper in homemade design electrolytic cell, conical wires were obtained. The electric current recorded during electrodeposition reflects the geometry of the pore. The lengths of wires were 96 μm and 20 μm, corresponding to the thickness of membranes. X-Ray Diffraction analysis indicated that texture and orientation of Cu wire were polycrystalline.

  4. A study of radon and thoron release from Egyptian building materials using polymeric nuclear track detectors.

    PubMed

    Hafez, A F; Hussein, A S; Rasheed, N M

    2001-02-01

    The free exhalation rates of both thoron and radon, the specific activities of 224Ra, and 226Ra, and the physical properties, such as the emanation coefficients and radon effective diffusion coefficient of several building material samples were determined using LR-115 and CR-39 polymeric nuclear track detectors. The free areal exhalation rate was measured by the sealed cup-technique, whereas the radium content was obtained by the alpha-autoradiographic method. The calibration coefficient for thoron measurements in air using cylindrical cup equipped with LR-115 detector was estimated. Moreover, the calibration coefficients for measurements of the specific activities of 224Ra and 226Ra were also evaluated. New method was developed for evaluating the emanation coefficient as well as the diffusion coefficient of radon isotopes in the studied materials.

  5. Determination of the detection threshold for Polyethylene Terephthalate (PET) Nuclear Track Detector (NTD)

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, R.; Dey, S.; Ghosh, Sanjay K.; Maulik, A.; Raha, Sibaji; Syam, D.

    2016-03-01

    In this work we investigated the detection threshold of the polymer material Polyethylene Terephthalate (PET) intended to be used as Nuclear Track Detector (NTD) in the search for rare events (e.g. strangelets) in cosmic rays. 11 MeV 12C and 2 MeV proton beams from the accelerator at the Institute of Physics (IOP), Bhubaneswar were utilized for this study. The results show that the PET detector has a much higher detection threshold (Z / β ∼ 140) compared to many other commercially available and widely used detector materials like CR-39 (Z / β ∼ 6-20) or Makrofol (Z / β ∼ 57). This makes PET a particularly suitable detector material for testing certain phenomenological models which predict the presence of strangelets as low energy, heavily ionizing particles in cosmic radiation at high mountain altitudes.

  6. Practical advances in cortisol (F) and dehydroepiandrosterone sulfate (DS) radioimmunoassay using the microfilter paper method

    SciTech Connect

    Pang, S.; Shine, S.; Levine, L.S.; New, M.I.

    1980-04-01

    A new reliable microfilter paper technique for measuring F and DS by RIA has been developed to overcome the difficulties of venipuncture and the inconvenience of storage and transportation of serum samples. This method requires only a drop of whole capillary blood, to impregnate filter paper for obtaining a 1/8-inch disc specimen. The dried filter paper specimen was eluted with buffer, and a further diluted eluate was used in RIA directly for DS and, after ether extraction, for F. Steroid concentrations of F and DS were not detectable in either hemolysate of 20 ..mu..l of packed washed red blood cells or dexamethasone-suppressed whole blood specimens. The percent recoveries of both added radiolabeled and unlabeled steroid from whole blood filter paper specimens were similar to those of the plasma studies. These steroid concentrations remained unchanged in dried whole blood on filter paper for up to 30 days when stored at room temperature. Evaluation of plasma volume in disc samples with varying hematocrits (27% to 51%) indicated a constant plasma volume in the disc (1.52 to 1.72 ..mu..l per 1/8-inch disc) regardless of the hematocrit range. Furthermore, plasma concentrations of these steroids in the filter paper disc, based on a mean constant plasma volume in the disc (1.66 ..mu..l per 1/8-inch disc), were similar to that of the plasma sample. This indicates that the microfilter paper method has the specificity, sensitivity, accuracy, and precision of RIA of DS and F in whole plasma, and simplifies sample collection, storage, and transportation.

  7. Assessment of a Nuclear Affinity Labeling Method for Tracking Implanted Mesenchymal Stem Cells

    PubMed Central

    Leiker, Merced; Suzuki, Gen; Iyer, Vijay S.; Canty, John M.; Lee, Techung

    2010-01-01

    Therapeutic implantation of mesenchymal stem cells (MSCs) is entering the realm of clinical trials for several human diseases, and yet much remains uncertain regarding their dynamic distribution and cell fate after in vivo application. Discrepancies in the literature can be attributed in part to the use of different cell labeling/tracking methods and cell administration protocols. To identify a stem cell detection method suitable for myocardial implantation in a large animal model, we experimented on three different MSC labeling methods: adenovirus-mediated expression of enhanced green fluorescence protein (EGFP) and β-galactosidase (LacZ), and nuclear staining with DAPI. Intramuscular and intracoronary administrations of labeled porcine MSCs identified the nuclear affinity dye to be a reliable stem cell tracking marker. Stem cell identification is facilitated by an optimized live cell labeling condition generating bright blue fluorescence sharply confined to the nucleus. DAPI-labeled MSCs retained full viability, ceased proliferation, and exhibited an increased differentiation potential. The labeled MSCs remained fully active in expressing key growth factor and cytokine genes, and notably exhibited enhanced expression of the chemokine receptor CXCR4 and its ligand SDF1, indicating their competency in response to tissue injury. Histological analysis revealed that approximately half a million MSCs or ∼2% of the administered MSCs remained localized in the normal pig heart 2 weeks after coronary infusion. That the vast majority of these identified MSCs were interstitial indicated the ability of MSCs to migrate across the coronary endothelium. No evidence was obtained indicating MSC differentiation to cardiomyocyte. PMID:19069634

  8. Automatic neutron dosimetry system based on fluorescent nuclear track detector technology.

    PubMed

    Akselrod, M S; Fomenko, V V; Bartz, J A; Haslett, T L

    2014-10-01

    For the first time, the authors are describing an automatic fluorescent nuclear track detector (FNTD) reader for neutron dosimetry. FNTD is a luminescent integrating type of detector made of aluminium oxide crystals that does not require electronics or batteries during irradiation. Non-destructive optical readout of the detector is performed using a confocal laser scanning fluorescence imaging with near-diffraction limited resolution. The fully automatic table-top reader allows one to load up to 216 detectors on a tray, read their engraved IDs using a CCD camera and optical character recognition, scan and process simultaneously two types of images in fluorescent and reflected laser light contrast to eliminate false-positive tracks related to surface and volume crystal imperfections. The FNTD dosimetry system allows one to measure neutron doses from 0.1 mSv to 20 Sv and covers neutron energies from thermal to 20 MeV. The reader is characterised by a robust, compact optical design, fast data processing electronics and user-friendly software.

  9. Defense Nuclear Enterprise: DOD Has Established Processes for Implementing and Tracking Recommendations to Improve Leadership, Morale, and Operations

    DTIC Science & Technology

    2016-07-14

    guidance (including the Secretary of Defense memo Nuclear Enterprise Review Corrective Action Implementation), and documents from the Office of Cost ...the recommendations. The tracking tool currently contains hundreds of unique milestones and metrics, and additional milestones and metrics are still...holder may be necessary if you wish to reproduce this material separately. The Government Accountability Office, the audit

  10. A fusion nuclear science facility for a fast-track path to DEMO

    DOE PAGES

    Garofalo, A. M.; Abdou, M. A.; Canik, John M.; ...

    2014-04-24

    An accelerated fusion energy development program, a fast-track approach, requires proceeding with a nuclear and materials testing program in parallel with research on burning plasmas, ITER. A Fusion Nuclear Science Facility (FNSF) would address many of the key issues that need to be addressed prior to DEMO, including breeding tritium and completing the fuel cycle, qualifying nuclear materials for high fluence, developing suitable materials for the plasma-boundary interface, and demonstrating power extraction. The Advanced Tokamak (AT) is a strong candidate for an FNSF as a consequence of its mature physics base, capability to address the key issues, and the directmore » relevance to an attractive target power plant. The standard aspect ratio provides space for a solenoid, assuring robust plasma current initiation,and for an inboard blanket, assuring robust tritium breeding ratio (TBR) >1 for FNSF tritium self-sufficiency and building of inventory needed to start up DEMO. An example design point gives a moderate sized Cu-coil device with R/a = 2.7 m/0.77 κ = 2.3, BT= 5.4 T, IP = 6.6 MA, βN = 2.75, Pfus = 127 MW. The modest bootstrap fraction of fBS = 0.55 provides an opportunity to develop steady state with sufficient current drive for adequate control. Lastly, proceeding with a FNSF in parallel with ITER provides a strong basis to begin construction of DEMO upon the achievement of Q ~ 10 in ITER.« less

  11. A fusion nuclear science facility for a fast-track path to DEMO

    SciTech Connect

    Garofalo, A. M.; Abdou, M. A.; Canik, John M.; Chan, Vincent S.; Hyatt, A. W.; Hill, D. N.; Morley, N. B.; Navratil, G. A.; Sawan, M. E.; Taylor, T. S.; Wong, C. P. C.; Wu, W.; Ying, Alice

    2014-04-24

    An accelerated fusion energy development program, a fast-track approach, requires proceeding with a nuclear and materials testing program in parallel with research on burning plasmas, ITER. A Fusion Nuclear Science Facility (FNSF) would address many of the key issues that need to be addressed prior to DEMO, including breeding tritium and completing the fuel cycle, qualifying nuclear materials for high fluence, developing suitable materials for the plasma-boundary interface, and demonstrating power extraction. The Advanced Tokamak (AT) is a strong candidate for an FNSF as a consequence of its mature physics base, capability to address the key issues, and the direct relevance to an attractive target power plant. The standard aspect ratio provides space for a solenoid, assuring robust plasma current initiation,and for an inboard blanket, assuring robust tritium breeding ratio (TBR) >1 for FNSF tritium self-sufficiency and building of inventory needed to start up DEMO. An example design point gives a moderate sized Cu-coil device with R/a = 2.7 m/0.77 κ = 2.3, BT= 5.4 T, IP = 6.6 MA, βN = 2.75, Pfus = 127 MW. The modest bootstrap fraction of fBS = 0.55 provides an opportunity to develop steady state with sufficient current drive for adequate control. Lastly, proceeding with a FNSF in parallel with ITER provides a strong basis to begin construction of DEMO upon the achievement of Q ~ 10 in ITER.

  12. Can Microfiltered Seminal Plasma Preserve the Morphofunctional Characteristics of Porcine Spermatozoa in the Absence of Antibiotics? A Preliminary Study.

    PubMed

    Barone, F; Ventrella, D; Zannoni, A; Forni, M; Bacci, M L

    2016-08-01

    Artificial insemination is extensively performed in pig farms in Europe, the United States and Canada. Antibiotics are typically added to the inseminating dose to limit bacterial growth during liquid phase storage at 16°C, as bacterial contamination is unavoidable. The World Organization for Animal Health (OIE) and the Food and Agriculture Organization (FAO) take action to control and reduce antibiotic use in animals as more bacteria are becoming resistant to antimicrobials. To avoid the use of antibiotics, we prepared inseminating doses using microfiltered seminal plasma (SP). Microfiltration is a common technology used to reduce bacterial contamination but may retain seminal substances, influencing sperm quality during storage. Therefore, the aim of this study was to evaluate the morphofunctional parameters of spermatozoa during storage at 16°C in doses prepared with or without microfiltered SP, with or without the addition of antibiotics, in a Latin square design. Artificial insemination doses with microfiltered SP and without antibiotic addition preserved spermatozoa viability, mitochondrial membrane potential, acrosome integrity and objective motility, with absolute values equal or even better than those observed in conventional doses. In conclusion, although the results could be considered preliminary due to the small sample size, this study suggests that microfiltration of SP can be a simple method, feasible on farms, to replace antibiotic use in extended doses stored in the liquid phase at 16°C for up to 7 days. © 2016 Blackwell Verlag GmbH.

  13. Track structure based modelling of light ion radiation effects on nuclear and mitochondrial DNA

    NASA Astrophysics Data System (ADS)

    Schmitt, Elke; Ottolenghi, Andrea; Dingfelder, Michael; Friedland, Werner; Kundrat, Pavel; Baiocco, Giorgio

    2016-07-01

    Space radiation risk assessment is of great importance for manned spaceflights in order to estimate risks and to develop counter-measures to reduce them. Biophysical simulations with PARTRAC can help greatly to improve the understanding of initial biological response to ionizing radiation. Results from modelling radiation quality dependent DNA damage and repair mechanisms up to chromosomal aberrations (e.g. dicentrics) can be used to predict radiation effects depending on the kind of mixed radiation field exposure. Especially dicentric yields can serve as a biomarker for an increased risk due to radiation and hence as an indicator for the effectiveness of the used shielding. PARTRAC [1] is a multi-scale biophysical research MC code for track structure based initial DNA damage and damage response modelling. It integrates physics, radiochemistry, detailed nuclear DNA structure and molecular biology of DNA repair by NHEJ-pathway to assess radiation effects on cellular level [2]. Ongoing experiments with quasi-homogeneously distributed compared to sub-micrometre focused bunches of protons, lithium and carbon ions allow a separation of effects due to DNA damage complexity on nanometre scale from damage clustering on (sub-) micrometre scale [3, 4]. These data provide an unprecedented benchmark for the DNA damage response model in PARTRAC and help understand the mechanisms leading to cell killing and chromosomal aberrations (e.g. dicentrics) induction. A large part of space radiation is due to a mixed ion field of high energy protons and few heavier ions that can be only partly absorbed by the shielding. Radiation damage induced by low-energy ions significantly contributes to the high relative biological efficiency (RBE) of ion beams around Bragg peak regions. For slow light ions the physical cross section data basis in PARTRAC has been extended to investigate radiation quality effects in the Bragg peak region [5]. The resulting range and LET values agree with ICRU data

  14. Track-hole formation of alpha-particle and recoil nuclei in an LR-115 nuclear track detector exposed to neutrons

    NASA Astrophysics Data System (ADS)

    Hafez, A. F.; Khalil, G. I.

    1994-10-01

    The response function V(REL) of an LR-115 polymeric nuclear track detector has been used to determine the V( R) sensitivity functions for recoil nuclei which are produced by the interactions of fast neutrons with the detector material. For an external radiator placed in close contact with the LR-115 detector, the sensitivity functions have also been determined for the generated nuclei from the (n, α) reaction of thermal neutrons with the radiator material. The REL and the range for the studied nuclei as a function of their energies were calculated by using the BASIC-E version of Henke and Benton's programme. The theory of etch-track kinetics which depends on the V( R) function is used to predict the residual thickness necessary for track-hole formation of a charged particle at different angles by normally incident neutrons. The theoretical treatments were found to be in fair agreement with the previously obtained data for other cellulose nitrate track detectors.

  15. A measurement of the angular distribution of the diffuse optical transmittance of etched nuclear tracks in CR-39

    SciTech Connect

    Vázquez-López, C.; Zendejas-Leal, B. E.; Bogard, James S; Golzarri, J. I.; Espinosa Garcia, Guillermo

    2009-01-01

    This paper presents a device to measure the angular distribution of the diffuse optical transmittance produced by etched nuclear tracks in polyallyl diglycol carbonate (PADC) detector. The device makes use of a stepper motor to move an array of four photodetectors around the sample in 1.8-degree steps. The integrated transmitted light was observed to increase monotonically with the etched track density in a range from zero to 2.8 x 10^5 per cm^2, using a neutron Am Be source.

  16. Registration of alpha particles in Makrofol-E nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Rammah, Y. S.; Abdalla, Ayman M.; Ashraf, O.; Ashry, A. H.

    2016-06-01

    Fast detection of alpha particles in the range from 1 to 5 MeV in Makrofol-E polycarbonate nuclear track detectors (PCTDs) using a new chemical etchant was investigated. 252Cf and 241Am-thin open sources were used for irradiating Makrofol-E detectors with fission fragments and alpha particles in air at normal pressure and temperature (NPT). A chain of experimental work has been carried out using new etchants to register alpha particle in short time in Makrofol-E polycarbonate detectors. The etching efficiency were exhibited a clear dependence on the amount of methanol in the etching solution and etching time. The optimized chemical condition obtained at this stage of development for 200 μm Makrofol-E detectors are (8 ml of 10 N NaOH + 2 ml CH3OH) etching solutions at 60 °C for 3 h. In this study; it is possible to observe energy detection windows for Makrofol-E detectors according to applied etching duration. Makrofol-E introduced the characteristic Bragg peak, which indicates the advantages of this detector as alpha spectrometer. Consequently, the suggested new etchant can be developed for heavy ions detection and monitoring radon levels and its daughters.

  17. Ion Beam Measurements of a Dense Plasma Focus Device Using CR 39 Nuclear Track Detectors

    NASA Astrophysics Data System (ADS)

    Ngoi, S. K.; Yap, S. L.; Wong, C. S.; Saadah, A. R.

    2008-05-01

    The project is carried out using a small Mather type plasma focus device powered by a 15 kV, 30 μF capacitor. The filling gas used is argon. The ion beam generated is investigated by both time resolved and time integrated methods. Investigation on the dynamic of the current sheath is also carried out in order to obtain an optimum condition for ion beam production. The angular distribution of the ion emission is measured at positions of 0° (end-on), 45° and 90° (side-on) by using CR-39 nuclear track detectors. The divergence of the ion beam is also determined using these detectors. A biased ion collector is used for time resolved measurement of the ion beam. Time of flight technique is employed for the determination of the ion beam energy. Average ion beam energy obtained is about 180 keV. The ion beam produced can be used for applications such as material surface modification and ion implantation.

  18. Development of an automated multisample scanning system for nuclear track etched detectors

    NASA Astrophysics Data System (ADS)

    Tawara, H.; Eda, K.; Takahashi, K.; Doke, T.; Hasebe, N.; Kodaira, S.; Ota, S.; Kurano, M.; Yasuda, N.

    2008-08-01

    We have developed an automated scanning system for handling a large number of nuclear track etched detectors (NTEDs). The system consists of a magazine station for sample storage, a robotic sample loader, a high-speed wide-area digital imaging microscope device (modified HSP-1000) and PitFit software for analyzing etch pits. We investigated the performance of the system using CR-39 plastic NTED samples exposed to high-energy heavy ions and fast neutrons. When applying the system to fast neutron dosimetry, the typical scanning speed was about 100 samples/day with a scan area of 4 cm 2/sample. The neutron doses obtained from a fully automatic measurement agreed closely with those from a semi-automatic measurement. These results indicate the feasibility of fully automatic scanning of CR-39 personal neutron dosimeters. The system is also expected to be applicable to future large-scale experiments using CR-39 plastic and BP-1 glass NTEDs for observing ultraheavy galactic cosmic rays with high mass resolution.

  19. EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER, PHASE 2

    SciTech Connect

    Fowley, M.

    2012-07-31

    Testing was conducted at the Savannah River National Laboratory (SRNL) to investigate filter membrane performance in an effort to increase rotary microfilter (RMF) throughput. Membranes were tested in the SpinTek Filtration, Inc. Static Test Cell (STC), which permitted quick and easy testing of several different membranes. Testing consisted of 100 hours tests with two different slurry feeds, based on recommendations from the phase 1 testing. One feed contained Monosodium Titanate (MST) solids in a simulated salt solution. The other feed contained simulated sludge batch 6 (SB6) solids in a simulated salt solution. Five membranes were tested, one each from filter manufactures Pall and Porvair and three from the Oak Ridge National Laboratory (ORNL). The membrane from Pall is the current membrane used on the latest generation RMF. The Porvair membrane performed well in previous STC tests as well as one of the ORNL membranes. The other two membranes from ORNL were recently developed and not available for the previous STC test. The results indicate that the Porvair filter performed best with the MST slurry and the ORNL SVB6-1B filter performed best with the SB6 slurry. Difficulty was encountered with the ORNL filters due to their dimensional thickness, which was greater than the recommended filter thickness for the STC. The STC equipment was modified to complete the testing of the ORNL filters.

  20. Development and integration of xerogel polymeric absorbance micro-filters into lab-on-chip systems.

    PubMed

    Carregal-Romero, Ester; Fernández-Sánchez, César; Eguizabal, Alma; Demming, Stefanie; Büttgenbach, Stephanus; Llobera, Andreu

    2012-10-08

    This work reports on the implementation of different absorption micro-filters based on a dye-doped hybrid organic-inorganic xerogel polymeric material synthesized by the sol-gel process. Microstructures containing eight different filter widths were fabricated in polydimethylsiloxane (PDMS), bonded to glass substrates and filled with the corresponding dye doped polymeric material by a soft lithography approach. The filtering capacity as a function of dye concentration and filter width was studied and revealed a linear dependence with both parameters, as expected according to the Beer-Lambert law. Zero passband transmittance values and relatively sharp stopband regions were achieved with all the filters, also showing rejection levels between -6 dB and -55 dB. Finally, such filters were monolithically integrated into a disposable fluorescence-based photonic lab-on-a-chip (PhLoC) approach. Calibration curves carried out with a model fluorophore target analyte showed an over two-fold increase in sensitivity and a thirty-fold decrease of the limit of detection (LOD) compared with the values recorded using the same PhLoC system but without the polymeric filter structure. The results presented herein clearly indicate the feasibility of these xerogel-based absorbance filtering structures for being applied as low-cost optical components that can be easily incorporated into disposable fluorescence-based photonic lab on a chip systems.

  1. Fabrication of large-area polymer microfilter membranes and their application for particle and cell enrichment.

    PubMed

    Hernández-Castro, Javier Alejandro; Li, Kebin; Meunier, Anne; Juncker, David; Veres, Teodor

    2017-05-31

    A vacuum assisted UV micro-molding (VAUM) process is proposed for the fabrication of freestanding and defect-free polymer membranes based on a UV-curable methacrylate polymer (MD 700). VAUM is a highly flexible and powerful method for fabricating low cost, robust, large-area membranes over 9 × 9 cm(2) with pore sizes from 8 to 20 μm in diameter, 20 to 100 μm in thickness, high aspect ratio (the thickness of the polymer over the diameter of the hole is up to 15 : 1), high porosity, and a wide variety of geometrical characteristics. The fabricated freestanding membranes are flexible while mechanically robust enough for post manipulation and handling, which allows them to be cut and integrated as a plastic cartridge onto thermoplastic 3D microfluidic devices with single or double filtration stages. Very high particle capture efficiencies (≈98%) have been demonstrated in the microfluidic devices integrated with polymer membranes, even when the size of the beads is very close to the size of the pores of the microfilter. About 85% of the capture efficiency has been achieved in cancer cell trapping experiments, in which a breast cancer cell line (MDA-MB-231) spiked with phosphate-buffered saline buffer when the pore size of the filter is 8 μm and the device is operated at a flow rate of 0.1 mL min(-1).

  2. Development and shelf-life determination of pasteurized, microfiltered, lactose hydrolyzed skim milk.

    PubMed

    Antunes, A E C; Silva E Alves, A T; Gallina, D A; Trento, F K H S; Zacarchenco, P B; Van Dender, A G F; Moreno, I; Ormenese, R C S C; Spadoti, L M

    2014-09-01

    The segment of the world population showing permanent or temporary lactose intolerance is quite significant. Because milk is a widely consumed food with an high nutritional value, technological alternatives have been sought to overcome this dilemma. Microfiltration combined with pasteurization can not only extend the shelf life of milk but can also maintain the sensory, functional, and nutritional properties of the product. This studied developed a pasteurized, microfiltered, lactose hydrolyzed (delactosed) skim milk (PMLHSM). Hydrolysis was performed using β-galactosidase at a concentration of 0.4mL/L and incubation for approximately 21h at 10±1°C. During these procedures, the degree of hydrolysis obtained (>90%) was accompanied by evaluation of freezing point depression, and the remaining quantity of lactose was confirmed by HPLC. Milk was processed using a microfiltration pilot unit equipped with uniform transmembrane pressure (UTP) ceramic membranes with a mean pore size of 1.4 μm and UTP of 60 kPa. The product was submitted to physicochemical, microbiological, and sensory evaluations, and its shelf life was estimated. Microfiltration reduced the aerobic mesophilic count by more than 4 log cycles. We were able to produce high-quality PMLHSM with a shelf life of 21 to 27d when stored at 5±1°C in terms of sensory analysis and proteolysis index and a shelf life of 50d in regard to total aerobic mesophile count and titratable acidity.

  3. Experimental study on non-woven filamentous fibre micro-filter with high filtration speed.

    PubMed

    Niu, Siping; Park, Kisoo; Guerra, Heidi B; Kim, Youngchul

    2015-01-01

    A laboratory study was undertaken to pursue the filter performance of a micro-filter module employing highly porous fibre media under a high filtration rate (≥1,500 m/day), faster than that of any conventional filter process. The effects of filtration rate, head loss, raw water turbidity, and filter aid chemicals on filter performance were analysed. In spite of the extremely high filtration rate, the filter achieved an attractive efficiency, reducing the raw water turbidity by over 80%. As with other filter systems, the filter aid used ((polyaluminium chloride (PAC)) greatly affected the performance of this particular fibre filter. Long-term repetitive runs were additionally carried out to confirm the reproducibility of the filter performance. Also, a comparison was carried out with other high-rate filter systems which are either being tested for use in experimental studies, or are already commercially available. This study reveals that the filter performance under a high filtration speed is still attractive especially as PAC is used. Due to the high porosity of the fibre, the filter had small head loss even though the filtration rate was high. These results ascertain that it is possible to operate the filters with high filtration rate achieving reliable treatment performance.

  4. Low-Cost Photolithographic Fabrication of Nanowires and Microfilters for Advanced Bioassay Devices

    PubMed Central

    Doan, Nhi M.; Qiang, Liangliang; Li, Zhe; Vaddiraju, Santhisagar; Bishop, Gregory W.; Rusling, James F.; Papadimitrakopoulos, Fotios

    2015-01-01

    Integrated microfluidic devices with nanosized array electrodes and microfiltration capabilities can greatly increase sensitivity and enhance automation in immunoassay devices. In this contribution, we utilize the edge-patterning method of thin aluminum (Al) films in order to form nano- to micron-sized gaps. Evaporation of high work-function metals (i.e., Au, Ag, etc.) on these gaps, followed by Al lift-off, enables the formation of electrical uniform nanowires from low-cost, plastic-based, photomasks. By replacing Al with chromium (Cr), the formation of high resolution, custom-made photomasks that are ideal for low-cost fabrication of a plurality of array devices were realized. To demonstrate the feasibility of such Cr photomasks, SU-8 micro-pillar masters were formed and replicated into PDMS to produce micron-sized filters with 3–4 µm gaps and an aspect ratio of 3. These microfilters were capable of retaining 6 µm beads within a localized site, while allowing solvent flow. The combination of nanowire arrays and micro-pillar filtration opens new perspectives for rapid R&D screening of various microfluidic-based immunoassay geometries, where analyte pre-concentration and highly sensitive, electrochemical detection can be readily co-localized. PMID:25774709

  5. Simultaneous Observation of Cells and Nuclear Tracks from the Boron Neutron Capture Reaction by UV-C Sensitization of Polycarbonate.

    PubMed

    Portu, Agustina; Rossini, Andrés Eugenio; Thorp, Silvia Inés; Curotto, Paula; Pozzi, Emiliano César Cayetano; Granell, Pablo; Golmar, Federico; Cabrini, Rómulo Luis; Martin, Gisela Saint

    2015-08-01

    The distribution of boron in tissue samples coming from boron neutron capture therapy protocols can be determined through the analysis of its autoradiography image on a nuclear track detector. A more precise knowledge of boron atom location on the microscopic scale can be attained by the observation of nuclear tracks superimposed on the sample image on the detector. A method to produce an "imprint" of cells cultivated on a polycarbonate detector was developed, based on the photodegradation properties of UV-C radiation on this material. Optimal conditions to generate an appropriate monolayer of Mel-J cells incubated with boronophenylalanine were found. The best images of both cells and nuclear tracks were obtained for a neutron fluence of 1013 cm-2, 6 h UV-C (254 nm) exposure, and 4 min etching time with a KOH solution. The imprint morphology was analyzed by both light and scanning electron microscopy. Similar samples, exposed to UV-A (360 nm) revealed no cellular imprinting. Etch pits were present only inside the cell imprints, indicating a preferential boron uptake (about threefold the incubation concentration). Comparative studies of boron absorption in different cell lines and in vitro evaluation of the effect of diverse boron compounds are feasible with this methodology.

  6. Unstable nuclei in dissociation of light stable and radioactive nuclei in nuclear track emulsion

    NASA Astrophysics Data System (ADS)

    Artemenkov, D. A.; Zaitsev, A. A.; Zarubin, P. I.

    2017-01-01

    A role of the unstable nuclei 6Be, 8Be and 9B in the dissociation of relativistic nuclei 7,9Be, 10B and 10,11C is under study on the basis of nuclear track emulsion exposed to secondary beams of the JINR Nuclotron. Contribution of the configuration 6Be + n to the 7Be nucleus structure is 8 ± 1% which is near the value for the configuration 6Li + p. Distributions over the opening angle of α-particle pairs indicate to a simultaneous presence of virtual 8Beg.s. and 8Be2+ states in the ground states of the 9Be and 10C nuclei. The core 9B is manifested in the 10C nucleus with a probability of 30 ± 4%. Selection of the 10C "white" stars accompanied by 8Beg.s. (9B) leads to appearance in the excitation energy distribution of 2α2 p "quartets" of the distinct peak with a maximum at 4.1 ± 0.3 MeV. 8Beg.s. decays are presented in 24 ± 7% of 2He + 2H events of the 11C coherent dissociation and 27 ± 11% of the 3He ones. The channel 9B + H amounts 14 ± 3%. The 8Bg.s. nucleus is manifested in the coherent dissociation 10B → 2He + H with a probability of 25 ± 5% including 13 ± 3% of 9B decays. A probability ratio of the mirror channels 9B + n and 9Be + p is estimated to be 10 ± 1.

  7. Comparing stochastic proton interactions simulated using TOPAS-nBio to experimental data from fluorescent nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Underwood, T. S. A.; Sung, W.; McFadden, C. H.; McMahon, S. J.; Hall, D. C.; McNamara, A. L.; Paganetti, H.; Sawakuchi, G. O.; Schuemann, J.

    2017-04-01

    Whilst Monte Carlo (MC) simulations of proton energy deposition have been well-validated at the macroscopic level, their microscopic validation remains lacking. Equally, no gold-standard yet exists for experimental metrology of individual proton tracks. In this work we compare the distributions of stochastic proton interactions simulated using the TOPAS-nBio MC platform against confocal microscope data for Al2O3:C,Mg fluorescent nuclear track detectors (FNTDs). We irradiated 8× 4× 0.5 mm3 FNTD chips inside a water phantom, positioned at seven positions along a pristine proton Bragg peak with a range in water of 12 cm. MC simulations were implemented in two stages: (1) using TOPAS to model the beam properties within a water phantom and (2) using TOPAS-nBio with Geant4-DNA physics to score particle interactions through a water surrogate of Al2O3:C,Mg. The measured median track integrated brightness (IB) was observed to be strongly correlated to both (i) voxelized track-averaged linear energy transfer (LET) and (ii) frequency mean microdosimetric lineal energy, \\overline{{{y}F}} , both simulated in pure water. Histograms of FNTD track IB were compared against TOPAS-nBio histograms of the number of terminal electrons per proton, scored in water with mass-density scaled to mimic Al2O3:C,Mg. Trends between exposure depths observed in TOPAS-nBio simulations were experimentally replicated in the study of FNTD track IB. Our results represent an important first step towards the experimental validation of MC simulations on the sub-cellular scale and suggest that FNTDs can enable experimental study of the microdosimetric properties of individual proton tracks.

  8. Deformability-based circulating tumor cell separation with conical-shaped microfilters: Concept, optimization, and design criteria.

    PubMed

    Aghaamoo, Mohammad; Zhang, Zhifeng; Chen, Xiaolin; Xu, Jie

    2015-05-01

    Circulating tumor cells (CTCs) separation technology has made positive impacts on cancer science in many aspects. The ability of detecting and separating CTCs can play a key role in early cancer detection and treatment. In recent years, there has been growing interest in using deformability-based CTC separation microfilters due to their simplicity and low cost. Most of the previous studies in this area are mainly based on experimental work. Although experimental research provides useful insights in designing CTC separation devices, there is still a lack of design guidelines based on fundamental understandings of the cell separation process in the filters. While experimental efforts face challenges, especially microfabrication difficulties, we adopt numerical simulation here to study conical-shaped microfilters using deformability difference between CTCs and blood cells for the separation process. We use the liquid drop model for modeling a CTC passing through such microfilters. The accuracy of the model in predicting the pressure signature of the system is validated by comparing it with previous experiments. Pressure-deformability analysis of the cell going through the channel is then carried out in detail in order to better understand how a CTC behaves throughout the filtration process. Different system design criteria such as system throughput and unclogging of the system are discussed. Specifically, pressure behavior under different system throughput is analyzed. Regarding the unclogging issue, we define pressure ratio as a key parameter representing the ability to overcome clogging in such CTC separation devices and investigate the effect of conical angle on the optimum pressure ratio. Finally, the effect of unclogging applied pressure on the system performance is examined. Our study provides detailed understandings of the cell separation process and its characteristics, which can be used for developing more efficient CTC separation devices.

  9. Deformability-based circulating tumor cell separation with conical-shaped microfilters: Concept, optimization, and design criteria

    PubMed Central

    Chen, Xiaolin; Xu, Jie

    2015-01-01

    Circulating tumor cells (CTCs) separation technology has made positive impacts on cancer science in many aspects. The ability of detecting and separating CTCs can play a key role in early cancer detection and treatment. In recent years, there has been growing interest in using deformability-based CTC separation microfilters due to their simplicity and low cost. Most of the previous studies in this area are mainly based on experimental work. Although experimental research provides useful insights in designing CTC separation devices, there is still a lack of design guidelines based on fundamental understandings of the cell separation process in the filters. While experimental efforts face challenges, especially microfabrication difficulties, we adopt numerical simulation here to study conical-shaped microfilters using deformability difference between CTCs and blood cells for the separation process. We use the liquid drop model for modeling a CTC passing through such microfilters. The accuracy of the model in predicting the pressure signature of the system is validated by comparing it with previous experiments. Pressure-deformability analysis of the cell going through the channel is then carried out in detail in order to better understand how a CTC behaves throughout the filtration process. Different system design criteria such as system throughput and unclogging of the system are discussed. Specifically, pressure behavior under different system throughput is analyzed. Regarding the unclogging issue, we define pressure ratio as a key parameter representing the ability to overcome clogging in such CTC separation devices and investigate the effect of conical angle on the optimum pressure ratio. Finally, the effect of unclogging applied pressure on the system performance is examined. Our study provides detailed understandings of the cell separation process and its characteristics, which can be used for developing more efficient CTC separation devices. PMID:26064193

  10. DEVELOPMENT OF A LAMINATED DISK FOR THE SPIN TEK ROTARY MICROFILTER

    SciTech Connect

    Herman, D.

    2011-06-03

    Funded by the Department of Energy Office of Environmental Management, EM-31, the Savannah River National Laboratory (SRNL) partnered with SpinTek Filtration{trademark} to develop a filter disk that would withstand a reverse pressure or flow during operation of the rotary microfilter. The ability to withstand a reverse pressure and flow eliminates a potential accident scenario that could have resulted in damage to the filter membranes. While the original welded filter disks have been shown to withstand and reverse pressure/flow in the static condition, the filter disk design discussed in this report will allow a reverse pressure/flow while the disks are rotating. In addition, the laminated disk increases the flexibility during filter startup and cleaning operations. The new filter disk developed by SRNL and SpinTek is manufactured with a more open structure significantly reducing internal flow restrictions in the disk. The prototype was tested at the University of Maryland and demonstrated to withstand the reverse pressure due to the centrifugal action of the rotary filter. The tested water flux of the disk was demonstrated to be 1.34 gpm in a single disk test. By comparison, the water flux of the current disk was 0.49 gpm per disk during a 25 disk test. The disk also demonstrated rejection of solids by filtering a 5 wt % Strontium Carbonate slurry with a filtrate clarity of less the 1.4 Nephelometric Turbidity Units (NTU) throughout the two hour test. The Savannah River National Laboratory (SRNL) has been working with SpinTek Filtration{trademark} to adapt the rotary microfilter for radioactive service in the Department of Energy (DOE) Complex. One potential weakness is the loose nature of the membrane on the filter disks. The current disk is constructed by welding the membrane at the outer edge of the disk. The seal for the center of the membrane is accomplished by an o-ring in compression for the assembled stack. The remainder of the membrane is free floating on

  11. Filtration of fullerene and copper oxide nanoparticles using surface-modified microfilters.

    PubMed

    Jeong, Seung-Woo; Kim, Hongyeol

    2014-09-01

    This study evaluated the filtration of engineered nanoparticles of fullerene and copper oxide (CuO) from water by using surface-modified microsized filters. The surfaces of microsized filters of cellulose acetate and glass fibers were coated with cationic and anionic surfactants to give them positively and negatively charged surfaces, respectively. Uncoated microfilters removed 30% of a fullerene suspension, while no nanosized CuO suspension was removed. Cationic surfactant-coated filters enhanced the removal efficiency up to 70% for the fullerene suspension, while the anionic surfactant-coated filters could not remove fullerene at all. The positively charged filters with cationic surfactant coating could easily adsorb negatively charged fullerenes on their surfaces. However, none of the surfactant-coated filters removed the CuO nanoparticles because the nanoparticles were not affected by the electrical charge of the filtration medium. The Hamaker constants of nanoparticles interacting with the filter materials in water were calculated to study these interactions. The Hamaker constant of fullerene interacting with cellulose acetate in water, 4.68E - 21 J, was higher than that of interacting with quartz in water, 2.59E - 21 J. However, the Hamaker constants of CuO interacting with quartz and cellulose acetate in water were both negative values, implying repulsive van der Waals interactions. The curves of potential energy of interaction between nanoparticles and the various filter media implied that the nanoparticles were very stable in water, and so, natural deposition of nanoparticles on the filters would not occur. Therefore, electrical bonding and hydrophobic interactions were the forces dominating fullerene removal by positively charged filters.

  12. Optimization of an enhanced ceramic micro-filter for concentrating E.coli in water

    NASA Astrophysics Data System (ADS)

    Zhang, Yushan; Guo, Tianyi; Xu, Changqing; Hong, Lingcheng

    2017-02-01

    Recently lower limit of detection (LOD) is necessary for rapid bacteria detection and analysis applications in clinical practices and daily life. A critical pre-conditioning step for these applications is bacterial concentration, especially for low level of pathogens. Sample volume can be largely reduced with an efficient pre-concentration process. Some approaches such as hollow-fiber ultra-filtration and electrokinetic technique have been applied to bacterial concentration. Since none of these methods can provide a concentrating method with a stable recovery efficiency, bacterial concentration still remains challenging Ceramic micro- filter can be used to concentrate the bacteria but the cross flow system keeps the bacteria in suspension. Similar harvesting bacteria using ultra-filtration showed an average recovery efficiency of 43% [1] and other studies achieved recovery rates greater than 50% [2]. In this study, an enhanced ceramic micro-filter with 0.14 μm pore size was proposed and demonstrated to optimize the concentration of E.coli. A high recovery rate (mean value >90%) and a high volumetric concentration ratio (>100) were achieved. Known quantities (104 to 106 CFU/ml) of E.coli cells were spiked to different amounts of phosphate buffered saline (0.1 to 1 L), and then concentrated to a final retentate of 5 ml to 10 ml. An average recovery efficiency of 95.3% with a standard deviation of 5.6% was achieved when the volumetric con- centration ratio was 10. No significant recovery rate loss was indicated when the volumetric concentration ratio reached up to 100. The effects of multiple parameters on E.coli recovery rate were also studied. The obtained results indicated that the optimized ceramic micro- filtration system can successfully concentrate E.coli cells in water with an average recovery rate of 90.8%.

  13. TESTING OF THE SPINTEK ROTARY MICROFILTER USING ACTUAL HANFORD WASTE SAMPLES

    SciTech Connect

    HUBER HJ

    2010-04-13

    The SpinTek rotary microfilter was tested on actual Hanford tank waste. The samples were a composite of archived Tank 241-AN-105 material and a sample representing single-shell tanks (SST). Simulants of the two samples have been used in non-rad test runs at the 222-S laboratory and at Savannah River National Laboratory (SRNL). The results of these studies are compared in this report. Two different nominal pore sizes for the sintered steel rotating disk filter were chosen: 0.5 and 0.1 {micro}m. The results suggest that the 0.5-{micro}m disk is preferable for Hanford tank waste for the following reasons: (1) The filtrate clarity is within the same range (<<4 ntu for both disks); (2) The filtrate flux is in general higher for the 0.5-{micro}m disk; and (3) The 0.1-{micro}m disk showed a higher likelihood of fouling. The filtrate flux of the actual tank samples is generally in the range of 20-30% compared to the equivalent non-rad tests. The AN-105 slurries performed at about twice the filtrate flux of the SST slurries. The reason for this difference has not been identified. Particle size distributions in both cases are very similar; comparison of the chemical composition is not conclusive. The sole hint towards what material was stuck in the filter pore holes came from the analysis of the dried flakes from the surface of the fouled 0.1-{micro}m disk. A cleaning approach developed by SRNL personnel to deal with fouled disks has been found adaptable when using actual Hanford samples. The use of 1 M nitric acid improved the filtrate flux by approximately two times; using the same simulants as in the non-rad test runs showed that the filtrate flux was restored to 1/2 of its original amount.

  14. Nuclear particle tracks and the regolith at the Luna 24 site

    NASA Technical Reports Server (NTRS)

    Crozaz, G.

    1978-01-01

    Track investigations of feldspars and pyroxenes in Luna 24 soils indicate that most of the grains resided within millimeters of the lunar surface. The two deepest samples appear to be less mature than the upper ones. Lack of correlation between tracks, agglutinates, and I sub S/FeO is puzzling and unique.

  15. Development of an energy discriminate CR-39(®) nuclear track etch dosimeter for Radon-220 gas measurements.

    PubMed

    Brown, J M C; Solomon, S; Tinker, R A

    2011-10-01

    An energy discriminate CR-39(®) nuclear track etch dosimeter for use in a (220)Rn and (222)Rn gas monitor has been developed and experimentally assessed. It utilises a thin film of Mylar(®) C to attenuate the alpha particle energies to allow only the damage tracks created by the 8.785 MeV alpha particles emitted from (212)Po of the (232)Th decay chain to be registered in the CR-39(®) plaque, allowing for the direct measurement of (220)Rn gas concentrations. The dosimeter was developed through a combination of experimental investigations and theoretical simulations using the Monte Carlo ion transport modelling program Stopping and Range of Ions in Materials (SRIM 2008). A film thickness of 54 μm has been shown to attenuate all alpha energies less then 7.7 MeV. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  16. Tracking nuclear wave-packet dynamics in molecular oxygen ions with few-cycle infrared laser pulses

    SciTech Connect

    De, S.; Bocharova, I. A.; Magrakvelidze, M.; Ray, D.; Cao, W.; Thumm, U.; Cocke, C. L.; Bergues, B.; Kling, M. F.; Litvinyuk, I. V.

    2010-07-15

    We have tracked nuclear wave-packet dynamics in doubly charged states of molecular oxygen using few-cycle infrared laser pulses. Bound and dissociating wave packets were launched and subsequently probed via a pair of 8-fs pulses of 790 nm radiation. Ionic fragments from the dissociating molecules were monitored by velocity-map imaging. Pronounced oscillations in the delay-dependent kinetic energy release spectra were observed. The occurrence of vibrational revivals permits us to identify the potential curves of the O{sub 2} dication which are most relevant to the molecular dynamics. These studies show the accessibility to the dynamics of such higher-charged molecules.

  17. Characteristics of flux and gel layer on microfilter and non-woven fabric filter surface based on anoxic-aerobic MBRs.

    PubMed

    Lee, Jung-Yeol; Choi, Bo-Kyung; Ahn, Kyu-Hong; Maeng, Sung Kyu; Song, Kyung-Guen

    2012-10-01

    Non-woven fabric filter- (NWFF) and microfilter-MBR modules were made using 100 μm polypropylene and 0.25 μm polyethylene materials, respectively. The performances and mechanisms of the two processes were investigated, including additional batch filtration tests to find the function of the dynamic gel layer on the membrane surface. The HRT of both MBRs was 9 h and the operating permeate flux was 13 L/m(2)/h. The two MBRs consisted of an anoxic and aerobic reactor. The NWFF or microfilter (MF) was submerged in each of the aerobic reactors. The two MBRs showed similar performances for the removal of organic matters, suspended solids and nitrogen. Cake formation on the NWFF contributed to major resistance, while the gel layer on the microfilter or internal fouling of the pores played a key role in the fouling of the membrane surface. The amount of soluble extracellular polymer substances (EPS) (13 mg/L) of the attached sludge on the NWFF surface was larger than that (11 mg/L) of that suspended sludge. Consequently, the functional gel layer for the coarse and microfilter is established based on the relationship among the EPS, transmembrane pressure and MLSS.

  18. What Was I Thinking? Eye-Tracking Experiments Underscore the Bias that Architecture Exerts on Nuclear Grading in Prostate Cancer

    PubMed Central

    Schaefer, Stephan C.; Mast, Fred W.; Lehr, Hans-Anton

    2012-01-01

    We previously reported that nuclear grade assignment of prostate carcinomas is subject to a cognitive bias induced by the tumor architecture. Here, we asked whether this bias is mediated by the non-conscious selection of nuclei that “match the expectation” induced by the inadvertent glance at the tumor architecture. 20 pathologists were asked to grade nuclei in high power fields of 20 prostate carcinomas displayed on a computer screen. Unknown to the pathologists, each carcinoma was shown twice, once before a background of a low grade, tubule-rich carcinoma and once before the background of a high grade, solid carcinoma. Eye tracking allowed to identify which nuclei the pathologists fixated during the 8 second projection period. For all 20 pathologists, nuclear grade assignment was significantly biased by tumor architecture. Pathologists tended to fixate on bigger, darker, and more irregular nuclei when those were projected before kigh grade, solid carcinomas than before low grade, tubule-rich carcinomas (and vice versa). However, the morphometric differences of the selected nuclei accounted for only 11% of the architecture-induced bias, suggesting that it can only to a small part be explained by the unconscious fixation on nuclei that “match the expectation”. In conclusion, selection of « matching nuclei » represents an unconscious effort to vindicate the gravitation of nuclear grades towards the tumor architecture. PMID:22666438

  19. Recommendations for Additional Design Development of Components for the SpinTek Rotary Microfilter Prior to Radioactive Service

    SciTech Connect

    Herman, D.T.

    2004-02-13

    The SpinTek rotary microfilter is being considered as an alternative to crossflow filtration. Prior testing evaluated the vendor's standard design for a 1-disk and 3-disk design. We noted several areas of improvement during the testing of the two filter systems that can be included in the 25-disk plant size unit.This report outlines several potential enhancements and improvements to the vendor's standard design which would extend the lifetime of the unit and increase the ability to perform maintenance for units deployed in radioactive service. The enhancements proposed in this report can be implemented to the current design with minimal impact to the cost and schedule of the purchase of the standard unit. An example of this is the replacement of the current mechanical seal with a bellows seal. The improvements proposed will require an extensive redesign of components found in the current system such as the filter chamber.

  20. Color changes in X-ray irradiated PM-355 and Makrofol DE 7-2 nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Nouh, Samir A.; Mohamed, Amal; Bahareth, Radiyah Ahmed; Abutalib, Maymona M.; Benthami, Kaoutar

    2014-03-01

    Effects of X-ray irradiation on the color changes of PM-355 and Makrofol DE 7-2 nuclear track detectors have been investigated. Samples from PM-355 and Makrofol DE 7-2 polycarbonates were irradiated with X-ray doses at levels between 10 and 250 kGy. The transmission of these samples in the wavelength range 370-780 nm, as well as any color changes, was studied. The Commission International de E'Claire (CIE units x, y and z) methodology was used in this work for the description of colored samples. The color differences between the non-irradiated sample and those irradiated with different X-ray doses were calculated. The results indicate that both PM-355 and Makrofol DE 7-2 detectors acquire color changes under X-ray irradiation, but the PM-355 detector has more response to color change than that of Makrofol DE 7-2.

  1. Structural and optical investigation of the effect of electron beam irradiation in a PM-355 nuclear track detector

    NASA Astrophysics Data System (ADS)

    Nouh, S. A.; Bahammam, S.

    2012-05-01

    The effect of electron beam irradiation on the structure and optical properties of a PM-355 solid-state nuclear track detector has been investigated. Samples from PM-355 were irradiated with electron beams with different doses ranging from 20 to 250 kGy. The structural and optical modifications in the electron beam-irradiated PM-355 samples have been studied as a function of dose using different characterization techniques such as Fourier transform infrared spectroscopy, Vickers hardness, refractive index and color difference measurements. The Commission International de E'Claire (CIE units x, y and z) methodology was used in this work for the description of colored samples. In addition, the color differences between the non-irradiated sample and those irradiated with different electron beam doses were calculated. The results indicate that the PM-355 detector acquires color changes under electron beam irradiation.

  2. The potential of nuclear magnetic resonance to track lipids in planta.

    PubMed

    Munz, Eberhard; Jakob, Peter M; Borisjuk, Ljudmilla

    2016-11-01

    Nuclear Magnetic Resonance (NMR) provides a highly flexible platform for non invasive analysis and imaging biological samples, since the manipulation of nuclear spin allows the tailoring of experiments to maximize the informativeness of the data. MRI is capable of visualizing a holistic picture of the lipid storage in living plant/seed. This review has sought to explain how the technology can be used to acquire functional and physiological data from plant samples, and how to exploit it to characterize lipid deposition in vivo. At the same time, we have referred to the current limitations of NMR technology as applied to plants, and in particular of the difficulty of transferring methodologies optimized for animal/medical subjects to plant ones. A forward look into likely developments in the field is included, anticipating its key future role in the study of living plant.

  3. Co-visualization of DNA damage and ion traversals in live mammalian cells using a fluorescent nuclear track detector

    PubMed Central

    Kodaira, Satoshi; Konishi, Teruaki; Kobayashi, Alisa; Maeda, Takeshi; Ahmad, Tengku Ahbrizal Farizal Tengku; Yang, Gen; Akselrod, Mark S.; Furusawa, Yoshiya; Uchihori, Yukio

    2015-01-01

    The geometric locations of ion traversals in mammalian cells constitute important information in the study of heavy ion-induced biological effect. Single ion traversal through a cellular nucleus produces complex and massive DNA damage at a nanometer level, leading to cell inactivation, mutations and transformation. We present a novel approach that uses a fluorescent nuclear track detector (FNTD) for the simultaneous detection of the geometrical images of ion traversals and DNA damage in single cells using confocal microscopy. HT1080 or HT1080–53BP1-GFP cells were cultured on the surface of a FNTD and exposed to 5.1-MeV/n neon ions. The positions of the ion traversals were obtained as fluorescent images of a FNTD. Localized DNA damage in cells was identified as fluorescent spots of γ-H2AX or 53BP1-GFP. These track images and images of damaged DNA were obtained in a short time using a confocal laser scanning microscope. The geometrical distribution of DNA damage indicated by fluorescent γ-H2AX spots in fixed cells or fluorescent 53BP1-GFP spots in living cells was found to correlate well with the distribution of the ion traversals. This method will be useful for evaluating the number of ion hits on individual cells, not only for micro-beam but also for random-beam experiments. PMID:25324538

  4. Co-visualization of DNA damage and ion traversals in live mammalian cells using a fluorescent nuclear track detector.

    PubMed

    Kodaira, Satoshi; Konishi, Teruaki; Kobayashi, Alisa; Maeda, Takeshi; Ahmad, Tengku Ahbrizal Farizal Tengku; Yang, Gen; Akselrod, Mark S; Furusawa, Yoshiya; Uchihori, Yukio

    2015-03-01

    The geometric locations of ion traversals in mammalian cells constitute important information in the study of heavy ion-induced biological effect. Single ion traversal through a cellular nucleus produces complex and massive DNA damage at a nanometer level, leading to cell inactivation, mutations and transformation. We present a novel approach that uses a fluorescent nuclear track detector (FNTD) for the simultaneous detection of the geometrical images of ion traversals and DNA damage in single cells using confocal microscopy. HT1080 or HT1080-53BP1-GFP cells were cultured on the surface of a FNTD and exposed to 5.1-MeV/n neon ions. The positions of the ion traversals were obtained as fluorescent images of a FNTD. Localized DNA damage in cells was identified as fluorescent spots of γ-H2AX or 53BP1-GFP. These track images and images of damaged DNA were obtained in a short time using a confocal laser scanning microscope. The geometrical distribution of DNA damage indicated by fluorescent γ-H2AX spots in fixed cells or fluorescent 53BP1-GFP spots in living cells was found to correlate well with the distribution of the ion traversals. This method will be useful for evaluating the number of ion hits on individual cells, not only for micro-beam but also for random-beam experiments. © The Author 2014. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  5. Remedial actions of nuclear safety shot sites: Double Tracks and Clean Slates

    SciTech Connect

    Sanchez, M.; Shotton, M.; Lyons, C.

    1998-03-01

    Remedial actions of plutonium (Pu)-contaminated soils are in the preliminary stages of development at the Nevada Test Site (NTS). Interim clean-up actions were completed at the Double Tracks and Clean Slate 1 safety shot sites in 1996 and 1997, respectively. Soil at both sites, with a total transuranic activity greater than 20 picoCuries per gram (pCi/g), was excavated and shipped to the NTS for disposal. Characterization and assessment efforts were initiated at the Double Tracks site in 1995, and the clean-up of this site as an interim action was completed in 1996. Clean-up of this site consisted of taking site-specific data and applying rationale for dose and risk calculations in selecting parameter values for the interim corrective action level. The remediation process included excavating and stockpiling the contaminated soil and loading the soil into supersacks with approximately 1,513 cubic meters (53,500 cubic feet) being shipped to the NTS for disposal. In 1997, remediation began on the Clean Slate 1 site on which characterization had already been completed using a very similar approach; however, the site incorporated lessons learned, cost efficiencies, and significant improvements to the process. This paper focuses on those factors and the progress that has been made in cleaning up the sites. The application of a technically reasonable remediation method, as well as the cost factors that supported transport and disposal of the low-level waste in bulk are discussed.

  6. In Vivo Tracking of Cell Therapies for Cardiac Diseases with Nuclear Medicine

    PubMed Central

    Moreira, Mayra Lorena; da Costa Medeiros, Priscylla; de Souza, Sergio Augusto Lopes; Rosado-de-Castro, Paulo Henrique

    2016-01-01

    Even though heart diseases are amongst the main causes of mortality and morbidity in the world, existing treatments are limited in restoring cardiac lesions. Cell transplantations, originally developed for the treatment of hematologic ailments, are presently being explored in preclinical and clinical trials for cardiac diseases. Nonetheless, little is known about the possible efficacy and mechanisms for these therapies and they are the center of continuous investigation. In this scenario, noninvasive imaging techniques lead to greater comprehension of cell therapies. Radiopharmaceutical cell labeling, firstly developed to track leukocytes, has been used successfully to evaluate the migration of cell therapies for myocardial diseases. A substantial rise in the amount of reports employing this methodology has taken place in the previous years. We will review the diverse radiopharmaceuticals, imaging modalities, and results of experimental and clinical studies published until now. Also, we report on current limitations and potential advances of radiopharmaceutical labeling for cell therapies in cardiac diseases. PMID:26880951

  7. Characteristics of submicron pores obtained by chemical etching of nuclear tracks in polycarbonate films

    NASA Astrophysics Data System (ADS)

    Guillot, G.; Rondelez, F.

    1981-12-01

    Calibrated pores in the range 102-2×103 Å have been obtained by chemical etching of polycarbonate thin films irradiated with high energy krypton ions (500 MeV, Kr25+). Both the amorphous and the crystalline forms of polycarbonate (Makrofol, Bayer), further designated by their respective trade names N and KG, have been investigated up to thicknesses of 60 μm, close to the theoretical ion range of 77 μm. From conductivity studies, three different domains have been separated around the ion track: A highly damaged core of radius ?50 Å with a fast etching rate vT ≊104 Å/min, an intermediate zone of radius ?500 Å with an etching rate vI = 0.9 Å/min, an outer region with an etching rate equal to that of the undamaged material, vG = 0.47 Å/min. These observations are compatible with the delta ray model for track formation in plastic materials. Scanning electron microscope investigations have revealed that the pores formed in the N material are straight cylinders with a narrow distribution of the pore entrance diameters. On the other hand, the pores for the KG type are much less uniform and appear to be tapered, the difference between the two sides of the membrane being as much as 50%. These characteristics could be related to inhomogeneities in the morphological structure due to (i) the finite size of the crystalline domains and (ii) an asymetric manufacturer's processing of the film surfaces.

  8. Analysis of stress fractures associated with lameness in Thoroughbred flat racehorses training on different track surfaces undergoing nuclear scintigraphic examination.

    PubMed

    MacKinnon, M C; Bonder, D; Boston, R C; Ross, M W

    2015-05-01

    There is limited information regarding the impact of training track surface on the occurrence of stress fractures. To evaluate the impact of training track surface on the proportion of long bone and pelvic stress fractures associated with lameness in Thoroughbred horses in flat race training undergoing nuclear scintigraphic examination. Retrospective study. Scintigraphic examinations of Thoroughbred flat racehorses were evaluated from 2 hospitals (hospital A [Toronto Equine Hospital], 2003-2009, and hospital B [George D. Widener Hospital for Large Animals, School of Veterinary Medicine, University of Pennsylvania], 1994-2006). Horses admitted to hospital A trained at a single track, at which the main training surface changed from dirt to synthetic on 27 August 2006. Two distinct populations existed at hospital B: horses that trained on dirt (numerous trainers) and those that trained on turf (single trainer). All scintigraphic images were evaluated by a blinded reviewer. Fisher's exact test and logistic regression were used when appropriate, and significance was set at P<0.05. When reviewing 528 scintigraphic examinations from hospital A (257 dirt and 271 synthetic, numerous trainers), there was a greater proportion of stress fractures detected in scintigraphic examinations from horses training on a synthetic surface (31.7%) in comparison to scintigraphic examinations from horses training on a dirt surface (23.0%) at an earlier point in time (P = 0.03). There was a greater proportion of hindlimb/pelvic and tibial stress fractures diagnosed in horses from the synthetic surface-trained group than from the dirt-trained group at hospital A (P<0.04 and P = 0.03, respectively). This study provides evidence that training surface may affect the proportion of stress fractures diagnosed, but other factors, such as training philosophy, appear to be important. Future prospective investigations to fully elucidate the relationship between training track

  9. Analysis system of submicron particle tracks in the fine-grained nuclear emulsion by a combination of hard x-ray and optical microscopy

    SciTech Connect

    Naka, T.; Asada, T.; Yoshimoto, M.; Katsuragawa, T.; Tawara, Y.; Umemoto, A.; Suzuki, Y.; Terada, Y.; Takeuchi, A.; Uesugi, K.; Kimura, M.

    2015-07-15

    Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several μm to more than 1000 μm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are insufficient due to their poor resolution. In this study, we developed a new system and method using an optical microscope system for rough candidate selection and the hard X-ray microscope system at SPring-8 for high-precision analysis with a resolution of better than 70 nm resolution. Furthermore, we demonstrated the analysis of submicron-length tracks with a matching efficiency of more than 99% and position accuracy of better than 5 μm. This system is now running semi-automatically.

  10. FAST TRACK PAPER: Regional observations of the second North Korean nuclear test on 2009 May 25

    NASA Astrophysics Data System (ADS)

    Shin, Jin Soo; Sheen, Dong-Hoon; Kim, Geunyoung

    2010-01-01

    The suspicious seismic event that occurred in the northern Korean Peninsula on 2009 May 25 was declared to be the second underground nuclear test (NK2ND) by North Korea. We investigated the characteristics of NK2ND using seismic signals recorded at regional-distance stations in South Korea and China. The Pn/Lg ratios of NK2ND definitely discriminate this event from two nearby natural earthquakes at frequencies above 4 Hz. Full moment tensor inversion of full waveform data shows that NK2ND had a very large isotropic component. Pure isotropic moment tensor inversion also resulted in good recovery of observed waveforms, with clear indication that NK2ND was explosive in origin. The moment magnitude (Mw) from the full moment tensor inversion was estimated to be 4.5 and network-averaged values of 4.6 and 3.6 were calculated for rms mb(Lg) and Ms(VMAX), respectively. Although mb - Ms signature has been considered one of the most reliable discriminants for separating explosions and earthquakes, this signature showed poor discrimination in the case of NK2ND. The Pn/Lg ratios and moment tensor inversion give more reliable evidence than does the mb - Ms for classifying the suspicious event in the northern Korean Peninsula as a possible explosion. The characteristics of NK2ND are also quite similar to those of the first North Korean nuclear test on 2006 October 9.

  11. TESTING AND EVALUATION OF THE MODIFIED DESIGN OF THE 25-DISK ROTARY MICROFILTER

    SciTech Connect

    Herman, D; Michael Poirier, M; Samuel Fink, S

    2006-09-29

    This report details redesign of a commercially available rotary microfilter to meet the operational and maintenance requirements for radioactive service. Personnel developed the design and coordinated procurement of two filters followed by testing of one unit. System testing examined the ability to rinse soluble material from the system, filtration performance using several insoluble solids loadings, effectiveness in washing sludge, amount of wear to parts and maintenance of the system including the insertion and removal of the filter stack, and the ability to flush solids from the system. The test program examined flushing the filter for soluble material by filling the system with a Rhodamine WT dye solution. Results showed that draining the system and rinsing with 50 gallons of water resulted in grater than 100X reduction of the dye concentration. Personnel determined filter performance using various amounts of insoluble sludge solids ranging from 0.06 to 15 weight percent (wt%) insoluble solids in a 3 molar (M) sodium simulated supernate. Through approximately 120 hours of start-and-stop (i.e., day shift) operation and various insoluble solids loadings, the filter produced filtration rates between 3 and 7 gallons per minute (gpm) (0.12-0.29 gpm/ft{sup 2}) for a 25-disk filter. Personnel washed approximately 80 gallons of simulated sludge using 207 gallons of inhibited water. Washing occurred at constant volume with wash water fed to a well mixed tank at the same rate as filtrate removal. Performance measurement involved collecting and analyzing samples throughout the washing for density and sodium content. Results showed an effective washing, mimicking a predicted dilution calculation for a well mixed tank and reducing the sodium concentration from 3.2 M to less than 0.3 M. Filtration rates during the washing process ranged between 3 and 4.3 gpm for one filter unit. The filter system then concentrated the washed 15 wt% insoluble solids slurry to approximately 20

  12. Tracking thermal degradation on passion fruit juice through Nuclear Magnetic Resonance and chemometrics.

    PubMed

    Soares, Marcia Valeria L; Alves Filho, Elenilson G; Silva, Lorena Mara A; Novotny, Etelvino Henrique; Canuto, Kirley Marques; Wurlitzer, Nedio Jair; Narain, Narendra; de Brito, Edy Sousa

    2017-03-15

    Thermal food processing mainly aims to control microorganism in order to extend its shelf life. However, it may induce chemical and nutritional changes in foodstuff. The Nuclear Magnetic Resonance (NMR) coupled to multivariate analysis was used to evaluate the effect of different thermal processing conditions (85 and 140°C for 4; 15; 30; and 60s) on the passion fruit juice using an Armfield pasteurizer. Through this approach it was possible to identify the changes in the juice composition. The temperature and the time lead to a hydrolysis of the sucrose to glucose and fructose. Additionally, juice submitted to 140°C for 60s results in the degradation of the sucrose and the formation of 5-(hydroxymethyl)-2-furfural (HMF). Despite no novel chemical marker has been identified, the (1)H NMR chemometrics approach may contribute in the choice of the temperature and time to be employed in the juice processing.

  13. Direct measurements of radon activity in water from various natural sources using nuclear track detectors.

    PubMed

    Marques, Adilson Lima; Dos Santos, Wlademir; Geraldo, Luiz Paulo

    2004-06-01

    Radon activities measured in several types of natural waters from the Santos region in Brazil are presented. Makrofol E polycarbonate plastic detector was used. The detector foils were exposed to radon emanating from the water samples for 30 days in a system of two tightly coupled cups, one of which contained the detector foil and the other hosted the analyzed water sample. After irradiation and chemical etching of the plastic foils, the tracks produced by the alpha particles emitted by radon and its progeny were counted with a system consisting of an optical microscope and a video camera. The measured radon radioactivities ranged from 0.95 to 36.00 Bq/l for ground waters, from 0.30 to 0.54 Bq/l for sea waters, from 0.39 to 0.47 Bq/l for tap waters, from 0.43 to 2.40 Bq/l for river waters, and amounted to 2.35 Bq/l for water from the Santos/São Vicente public water supply.

  14. Modifications induced by gamma irradiation to Makrofol polymer nuclear track detector.

    PubMed

    Tayel, A; Zaki, M F; El Basaty, A B; Hegazy, Tarek M

    2015-03-01

    The aim of the present study was extended from obtaining information about the interaction of gamma rays with Makrofol DE 7-2 track detector to introduce the basis that can be used in concerning simple sensor for gamma irradiation and bio-engineering applications. Makrofol polymer samples were irradiated with 1.25 MeV (60)Co gamma radiations at doses ranging from 20 to 1000 kG y. The modifications of irradiated samples so induced were analyzed using UV-vis spectrometry, photoluminescence spectroscopy, and the measurements of Vickers' hardness. Moreover, the change in wettability of irradiated Makrofol was investigated by the contact angle determination of the distilled water. UV-vis spectroscopy shows a noticeable decrease in the energy band gap due to gamma irradiation. This decrease could be attributed to the appearance of a shift to UV spectra toward higher wavelength region after irradiation. Photoluminescence spectra reveal a remarkable change in the integrated photoluminescence intensity with increasing gamma doses, which may be resulted from some matrix disorder through the creation of some defected states in the irradiated polymer. The hardness was found to increase from 4.78 MPa for the unirradiated sample to 23.67 MPa for the highest gamma dose. The contact angle investigations show that the wettability of the modified samples increases with increasing the gamma doses. The result obtained from present investigation furnishes evidence that the gamma irradiations are a successful technique to modify the Makrofol DE 7-2 polymer properties to use it in suitable applications.

  15. Response of TLD-albedo and nuclear track dosimeters exposed to plutonium sources

    SciTech Connect

    Brackenbush, L.W.; Baumgartner, W.V.; Fix, J.J.

    1991-12-01

    Neutron dosimetry has been extensively studied at Hanford since the mid-1940s. At the present time, Hanford contractors use thermoluminescent dosimeter (TLD)-albedo dosimeters to record the neutron dose equivalent received by workers. The energy dependence of the TLD-albedo dosimeter has been recognized and documented since introduced at Hanford in 1964 and numerous studies have helped assure the accuracy of dosimeters. With the recent change in Hanford`s mission, there has been a significant decrease in the handling of plutonium tetrafluoride, and an increase in the handling of plutonium metal and plutonium oxide sources. This study was initiated to document the performance of the current Hanford TLD-albedo dosimeter under the low scatter conditions of the calibration laboratory and under the high scatter conditions in the work place under carefully controlled conditions at the Plutonium Finishing Plant (PFP). The neutron fields at the PFP facility were measured using a variety of instruments, including a multisphere spectrometer, tissue equivalent proportional counters, and specially calibrated rem meters. Various algorithms were used to evaluate the TLD-albedo dosimeters, and the results are given in this report. Using current algorithms, the dose equivalents evaluated for bare sources and sources with less than 2.5 cm (1 in.) of acrylic plastic shielding in high scatter conditions typical of glove box operations are reasonably accurate. Recently developed CR-39 track etch dosimeters (TEDs) were also exposed in the calibration laboratory and at the PFP. The results indicate that the TED dosimeters are quite accurate for both bare and moderated neutron sources. Until personnel dosimeter is available that incorporates a direct measure of the neutron dose to a person, technical uncertainties in the accuracy of the recorded data will continue.

  16. Response of TLD-albedo and nuclear track dosimeters exposed to plutonium sources

    SciTech Connect

    Brackenbush, L.W.; Baumgartner, W.V.; Fix, J.J.

    1991-12-01

    Neutron dosimetry has been extensively studied at Hanford since the mid-1940s. At the present time, Hanford contractors use thermoluminescent dosimeter (TLD)-albedo dosimeters to record the neutron dose equivalent received by workers. The energy dependence of the TLD-albedo dosimeter has been recognized and documented since introduced at Hanford in 1964 and numerous studies have helped assure the accuracy of dosimeters. With the recent change in Hanford's mission, there has been a significant decrease in the handling of plutonium tetrafluoride, and an increase in the handling of plutonium metal and plutonium oxide sources. This study was initiated to document the performance of the current Hanford TLD-albedo dosimeter under the low scatter conditions of the calibration laboratory and under the high scatter conditions in the work place under carefully controlled conditions at the Plutonium Finishing Plant (PFP). The neutron fields at the PFP facility were measured using a variety of instruments, including a multisphere spectrometer, tissue equivalent proportional counters, and specially calibrated rem meters. Various algorithms were used to evaluate the TLD-albedo dosimeters, and the results are given in this report. Using current algorithms, the dose equivalents evaluated for bare sources and sources with less than 2.5 cm (1 in.) of acrylic plastic shielding in high scatter conditions typical of glove box operations are reasonably accurate. Recently developed CR-39 track etch dosimeters (TEDs) were also exposed in the calibration laboratory and at the PFP. The results indicate that the TED dosimeters are quite accurate for both bare and moderated neutron sources. Until personnel dosimeter is available that incorporates a direct measure of the neutron dose to a person, technical uncertainties in the accuracy of the recorded data will continue.

  17. Tracking of airborne radionuclides from the damaged Fukushima Dai-ichi nuclear reactors by European networks.

    PubMed

    Masson, O; Baeza, A; Bieringer, J; Brudecki, K; Bucci, S; Cappai, M; Carvalho, F P; Connan, O; Cosma, C; Dalheimer, A; Didier, D; Depuydt, G; De Geer, L E; De Vismes, A; Gini, L; Groppi, F; Gudnason, K; Gurriaran, R; Hainz, D; Halldórsson, Ó; Hammond, D; Hanley, O; Holeý, K; Homoki, Zs; Ioannidou, A; Isajenko, K; Jankovic, M; Katzlberger, C; Kettunen, M; Kierepko, R; Kontro, R; Kwakman, P J M; Lecomte, M; Leon Vintro, L; Leppänen, A-P; Lind, B; Lujaniene, G; Mc Ginnity, P; Mc Mahon, C; Malá, H; Manenti, S; Manolopoulou, M; Mattila, A; Mauring, A; Mietelski, J W; Møller, B; Nielsen, S P; Nikolic, J; Overwater, R M W; Pálsson, S E; Papastefanou, C; Penev, I; Pham, M K; Povinec, P P; Ramebäck, H; Reis, M C; Ringer, W; Rodriguez, A; Rulík, P; Saey, P R J; Samsonov, V; Schlosser, C; Sgorbati, G; Silobritiene, B V; Söderström, C; Sogni, R; Solier, L; Sonck, M; Steinhauser, G; Steinkopff, T; Steinmann, P; Stoulos, S; Sýkora, I; Todorovic, D; Tooloutalaie, N; Tositti, L; Tschiersch, J; Ugron, A; Vagena, E; Vargas, A; Wershofen, H; Zhukova, O

    2011-09-15

    Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 ((131)I) and cesium isotopes ((137)Cs and (134)Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th. Time variations over a 20-day period and spatial variations across more than 150 sampling locations in Europe made it possible to characterize the contaminated air masses. After the Chernobyl accident, only a few measurements of the gaseous (131)I fraction were conducted compared to the number of measurements for the particulate fraction. Several studies had already pointed out the importance of the gaseous (131)I and the large underestimation of the total (131)I airborne activity level, and subsequent calculations of inhalation dose, if neglected. The measurements made across Europe following the releases from the Fukushima NPP reactors have provided a significant amount of new data on the ratio of the gaseous (131)I fraction to total (131)I, both on a spatial scale and its temporal variation. It can be pointed out that during the Fukushima event, the (134)Cs to (137)Cs ratio proved to be different from that observed after the Chernobyl accident. The data set provided in this paper is the most comprehensive survey of the main relevant airborne radionuclides from the Fukushima reactors, measured across Europe. A rough estimate of the total (131)I inventory that has passed over Europe during this period was <1% of the released amount. According to the measurements, airborne activity levels remain of no concern for public health in Europe.

  18. Calibration of solid state nuclear track detectors at high energy ion beams for cosmic radiation measurements: HAMLET results

    NASA Astrophysics Data System (ADS)

    Szabó, J.; Pálfalvi, J. K.

    2012-12-01

    The MATROSHKA experiments and the related HAMLET project funded by the European Commission aimed to study the dose burden of the crew working on the International Space Station (ISS). During these experiments a human phantom equipped with several thousands of radiation detectors was exposed to cosmic rays inside and outside the ISS. Besides the measurements realized in Earth orbit, the HAMLET project included also a ground-based program of calibration and intercomparison of the different detectors applied by the participating groups using high-energy ion beams. The Space Dosimetry Group of the Centre for Energy Research (formerly Atomic Energy Research Institute) participated in these experiments with passive solid state nuclear track detectors (SSNTDs). The paper presents the results of the calibration experiments performed in the years 2008-2011 at the Heavy Ion Medical Accelerator (HIMAC) of the National Institute of Radiological Sciences (NIRS), Chiba, Japan. The data obtained serve as update and improvement for the previous calibration curves which are necessary for the evaluation of the SSNTDs exposed in unknown space radiation fields.

  19. Synthesis and investigation by means of electron energy loss spectroscopy of metal replicas fabricated from nuclear microfilters

    NASA Astrophysics Data System (ADS)

    Yarygin, V. I.; Mironov, V. S.; Solovyev, N. P.; Kolninov, O. V.; Kolesnikova, V. V.; Chernyavsky, A. I.; Smolyansky, A. S.

    2001-12-01

    This paper deals with the investigation of the possibility of using metal replicas, which were synthesized on the basis of chemically treated and heavy ion irradiated polyethylene terephtalate (PET) films, as collector rough surfaces in thermionic energy converters (TEC) with the low factor of the slow electron reflection from the collector surface. These collector surfaces decrease the voltage loss and, correspondingly, increase the efficiency. The procedures of the nickel- and copper-based replicas' fabrication were developed. The presence of the surface microrelief in the form of bulges with the height of 5-6 μm and diameter of 0.1 μm (the surface density is ˜2×10 9 cm-2) changes substantially the reflective properties of metal surfaces on exposure to light over the visible and infra-red range: in the case of copper the reflected light intensity decreases by more than an order of magnitude; for the nickel rough surfaces, which have acquired the black color, we determined the practically full absence of the light reflection in the range of wavelengths from 0.4 to 50 μm. The same was noted when studying the interaction of slow electrons with the synthesized microrough surfaces: 20% decrease of the electron reflection factor was detected. In this way, the nature of a metal has a determining effect on the nature of the light interaction with the metal replicas. The conclusion is made that the obtained rough surface hold much promise for the use as the collector surfaces in the new generation of TEC.

  20. Effect of mesophilic lactobacilli and enterococci adjunct cultures on the final characteristics of a microfiltered milk Swiss-type cheese.

    PubMed

    Bouton, Yvette; Buchin, Solange; Duboz, Gabriel; Pochet, Sylvie; Beuvier, Eric

    2009-04-01

    The effect of four associations of adjunct cultures composed of mesophilic lactobacilli and enterococci, either solely or combined, on the microbiological, biochemical and sensory characteristics of Swiss-type cheese made using microfiltered cows' milk and supplemented with propionibacteria was studied. The global pattern of growth was similar to that generally observed in raw milk cheese and interactions between microflora were highlighted during ripening. Enterococci, which negatively affected the survival of streptococci starters, seemed to play a limited role in the formation of volatile compounds, probably due to their low levels throughout ripening. On the contrary, mesophilic lactobacilli, which affected the evolution of propionibacteria, enterococci and L. delbrueckii subsp. lactis starter counts, modified free amino acid content, production of volatile compounds and organoleptic properties of mature cheese. This population appeared to be of major importance in the formation of cheese flavor as it was positively related to numerous potential flavor compounds such as alcohols and their corresponding esters, acetaldehyde and 4-methyl-4-heptanone. The original mesophilic lactobacilli present in milk could play an important role in the sensorial diversity of raw milk Swiss-type cheeses such as Comte.

  1. Calibration of a solid state nuclear track detector (SSNTD) with high detection threshold to search for rare events in cosmic rays

    NASA Astrophysics Data System (ADS)

    Dey, S.; Gupta, D.; Maulik, A.; Raha, Sibaji; Saha, Swapan K.; Syam, D.; Pakarinen, J.; Voulot, D.; Wenander, F.

    2011-06-01

    We have investigated a commercially available polymer for its suitability as a solid state nuclear track detector (SSNTD). We identified that polymer to be polyethylene terephthalate (PET) and found that it has a higher detection threshold compared to many other widely used SSNTDs which makes this detector particularly suitable for rare event search in cosmic rays as it eliminates the dominant low Z background. Systematic studies were carried out to determine its charge response which is essential before any new material can be used as an SSNTD. In this paper we describe the charge response of PET to 129Xe, 78Kr and 49Ti ions from the REX-ISOLDE facility at CERN, present the calibration curve for PET and characterize it as a nuclear track detector.

  2. Theoretical feasibility study on neutron spectrometry with the polyallyldiglycol carbonate (PADC) solid-state nuclear track detector

    NASA Astrophysics Data System (ADS)

    Nikezic, D.; Yu, K. N.

    2015-01-01

    Neutron spectrometry with the polyallyldiglycol carbonate (PADC) film detector was analyzed in detail. The computer codes TRACK_TEST and TRACK_VISION, which were originally developed for studies on alpha-particle tracks, were modified to compute parameters of etched proton tracks developed in the PADC film detector and to simulate their appearance under an optical microscope in the transmission mode. It was shown that protons with same energy and recoil angle could produce different etched tracks with various size and shape, depending on the point of their creation. As such, it was necessary to employ multiple etching, and to measure the removed layer thickness and to record the track appearance after each etching step. A new variable, namely, the effective removed layer heff, was introduced as the difference between the total removed layer and the depth where the proton was created in the detector. A program modified from the TRACK_VISION code was used to plot the appearance of a number of representative etched proton tracks. For proton energies larger than 2 MeV, the V function for protons in PADC was found to be almost constant, so the simple formulas for major and minor axes of proton track openings could be used to determine the proton energy, recoiled angle as well as the energy of the neutron which caused the proton recoil. For lower proton energies, a databank of various proton tracks showing the track opening appearances and the track profiles should be created for comparison to facilitate the determination of the proton energy.

  3. Proteolytic Activity and Production of γ-Aminobutyric Acid by Streptococcus thermophilus Cultivated in Microfiltered Pasteurized Milk.

    PubMed

    Brasca, Milena; Hogenboom, Johannes A; Morandi, Stefano; Rosi, Veronica; D'Incecco, Paolo; Silvetti, Tiziana; Pellegrino, Luisa

    2016-11-16

    A set of 191 strains of Streptococcus thermophilus were preliminarily screened for the presence of the genes codifying for cell envelope-associated proteinase (prtS) and for glutamate decarboxylase (gadB) responsible for γ-aminobutyric acid (GABA) production. The growth and proteolytic activity of the gadB-positive strains (9 presenting the prtS gene and 11 lacking it) were studied in microfiltered pasteurized milk. Degradation of both caseins (capillary electrophoresis) and soluble nitrogen fractions (HPLC) and changes in the profile of free amino acids (FAAs; ion-exchange chromatography) were evaluated at inoculation and after 6 and 24 h of incubation at 41 °C. None of the strains was capable of hydrolyzing caseins and β-lactoglobulin, and only two hydrolyzed part of α-lactalbumin, these proteins being present in their native states in pasteurized milk. Contrarily, most strains were able to hydrolyze peptones and peptides. For initial growth, most strains relied on the FAAs present in milk, whereas, after 6 h, prtS(+) strains released variable amounts of FAA. One prtS(+) strain expressed a PrtS(-) phenotype, and two prtS(-) strains showed a rather intense proteolytic activity. Only five strains (all prtS(+)) produced GABA, in variable quantities (up to 100 mg/L) and at different rates, depending on the acidification strength. Addition of glutamate did not induce production of GABA in nonproducing strains that, however, unexpectedly were shown to adopt the degradation of arginine into citrulline and ornithine as an alternative acid resistance system and likely as a source of ATP.

  4. Studies of Fusion Protons from a 3He-D2 Plasma Focus using Nuclear Track Detectors

    SciTech Connect

    Springham, S. V.; Sim, T. H.; Lee, P.; Rawat, R. S.; Shutler, P. M. E.; Tan, T. L.; Patran, A.; Lee, S.

    2006-12-04

    Protons from the fusion reactions D(3He,p)4He and D(d,p)3H have been observed in a small plasma focus device operated with a 3He-D2 gas mixture. The partial pressures of the 3He and D2 gasses were in the ratio of 2:1, corresponding to an atomic number ratio of 1:1. Two groups of protons with energies of approximately 16MeV and 3MeV arising from the D(3He,p)4He and D(d,p)3H reactions, were recorded simultaneously using a double-layer arrangement of CR-39 polymer nuclear track detectors (each of thickness 1000{mu}m). As a result of the very different ranges of 16MeV and 3MeV protons, and the particle registration properties of CR-39, the D(d,p)3H protons were registered on the front-most CR-39 surface and the D(3He,p)4He protons were registered on the back-most surface of this double-layer configuration. A pinhole camera, containing the CR-39 detectors, was situated on the forward plasma focus axis in order to image the emission zones of protons for both fusion reactions. It was found that the D(3He,p)4He and D(d,p)3H proton yields were of similar magnitude, but their spatial distributions were very different. Results indicate that the D(3He,p)4He fusion was concentrated close to the plasma focus pinch column, while the D(d,p)3H fusion occurred at some distance from the pinch. Moreover, it appears that both the D(3He,p)4He and D(d,p)3H fusion yields are produced by beam-target mechanisms, with no significant thermonuclear contribution. To better understand the shape of the D(d,p)3H distribution, comparative experiments were performed with both a 4He-D2 gas mixture and pure D2 gas. The D(d,p)3H distributions obtained for the 3He-D2 and 4He-D2 cases were found to be very similar, but markedly different from that obtained with pure D2 gas. Possible explanations of these measured distributions are discussed.

  5. Characterization of solid state nuclear track detectors of the polyallyl-diglycol-carbonate (CR-39/PM-355) type for light charged particle spectroscopy

    SciTech Connect

    Malinowska, A. Jaskóła, M.; Korman, A.; Kuk, M.; Szydłowski, A.

    2014-12-15

    This paper presents a method which uses the characteristics of the etch pits induced in a polyallyl-diglycol-carbonate (PADC) detector of the CR-39/PM-355 type to estimate particle energy. This method is based on the data provided by a semiautomatic system that selects tracks according to two parameters, crater diameters, and mean gray level values. In this paper we used the results of the calibration measurements that were obtained in our laboratory in the period 2000–2014. Combining the information on the two parameters it is possible to determine unambiguously the incident projectile energy values. The paper presents the results of an attempt to estimate the energy resolution of the method when analyzing the tracks produced in the CR-39/PM-355 detector by energetic ions such as alpha particles, protons, and deuterons. We discuss the energy resolution of the measurement of light charged particle energy which is based on the parameters (crater diameter and mean gray level value) of tracks induced in solid state nuclear track detectors of the PADC type.

  6. Characterization of the Oum Er Rbia (Morocco) high basin karstic water sources by using solid state nuclear track detectors and radon as a natural tracer.

    PubMed

    Khalil, N; Misdaq, M A; Berrazzouk, S; Mania, J

    2002-06-01

    Uranium and thorium contents as well as radon alpha-activities per unit volume were evaluated inside different water samples by using a method based on calculating the CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs) detection efficiencies for the emitted alpha-particles and measuring the resulting track density rates. The validity of the SSNTD technique utilized was checked by analysing uranyl nitrate (UO2(NO3)26H2O) standard solutions. A relationship between water radon concentration and water transmission of different water sources belonging to two regions of the Middle Atlas (Morocco) water reservoir was found. The influence of the water flow rate as well as the permeability and fracture system of the host rocks of the sources studied was investigated.

  7. Results from a Field Trial of the Radio Frequency Based Cylinder Accountability and Tracking System at the Global Nuclear Fuel Americas Fuel Fabrication Facility

    SciTech Connect

    Fitzgerald, Peter; Laughter, Mark D; Martyn, Rose; Pickett, Chris A; Rowe, Nathan C; Younkin, James R; Shephard, Adam M

    2010-01-01

    The Cylinder Accountability and Tracking System (CATS) is a tool designed for use by the International Atomic Energy Agency (IAEA) to improve overall inspector efficiency through real-time unattended monitoring of cylinder movements, site specific rules-based event detection, and the capability to integrate many types of monitoring technologies. The system is based on the tracking of cylinder movements using (radio frequency) RF tags, and the collection of data, such as accountability weights, that can be associated with the cylinders. This presentation will cover the installation and evaluation of the CATS at the Global Nuclear Fuels (GNF) fuel fabrication facility in Wilmington, NC. This system was installed to evaluate its safeguards applicability, operational durability under operating conditions, and overall performance. An overview of the system design and elements specific to the GNF deployment will be presented along with lessons learned from the installation process and results from the field trial.

  8. Fast track, dynein-dependent nuclear targeting of human immunodeficiency virus Vpr protein; impaired trafficking in a clinical isolate.

    PubMed

    Caly, Leon; Kassouf, Vicki T; Moseley, Gregory W; Diefenbach, Russell J; Cunningham, Anthony L; Jans, David A

    2016-02-12

    Nuclear import of the accessory protein Vpr is central to infection by human immunodeficiency virus (HIV). We previously identified the Vpr F72L mutation in a HIV-infected, long-term non-progressor, showing that it resulted in reduced Vpr nuclear accumulation and altered cytoplasmic localisation. Here we demonstrate for the first time that the effects of nuclear accumulation of the F72L mutation are due to impairment of microtubule-dependent-enhancement of Vpr nuclear import. We use high resolution imaging approaches including fluorescence recovery after photobleaching and other approaches to document interaction between Vpr and the dynein light chain protein, DYNLT1, and impaired interaction of the F72L mutant with DYNLT1. The results implicate MTs/DYNLT1 as drivers of Vpr nuclear import and HIV infection, with important therapeutic implications.

  9. Role of {sup 8}Be {yields} 2 {alpha} intermediate nuclei in the fragmentation of {sup 16}O relativistic nuclei in nuclear track emulsions

    SciTech Connect

    Lepekhin, F. G.; Tkach, L. N.

    2012-08-15

    In searches along a track in the chamber irradiated at the Laboratory of High Energies at the Joint Institute for Nuclear Research (JINR, Dubna) with oxygen ions accelerated to a momentum of 4.5 GeV/c per nucleon, 215 events containing two or more doubly charged fragments of the primary nucleus were found. Emission angles in the track-emulsion plane were measured in these events. Their distribution is consistent with that which alpha particles are expected to have in an oxygen nucleus prior to its interaction with a track-emulsion nucleus. Events of the {sup 16}O {yields} 2{sup 8}Be {yields} 4{alpha} type were discovered for the first time. They are treated as events of the coherent electromagnetic dissociation of an oxygen nucleus. Among all events, about 14% of the {sup 8}Be {yields} 2{alpha} decays proceed through the ground state of spin-parity 0{sup +}; an approximately the same fraction of such decays proceed through the first excited state of spin-parity 2{sup +}.

  10. Image computing techniques to extrapolate data for dust tracking in case of an experimental accident simulation in a nuclear fusion plant

    SciTech Connect

    Camplani, M.; Malizia, A.; Gelfusa, M.; Poggi, L. A.; Ciparisse, J. F.; Richetta, M.; Gaudio, P.; Barbato, F.; Antonelli, L.; Salgado, L.

    2016-01-15

    In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles’ velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

  11. Image computing techniques to extrapolate data for dust tracking in case of an experimental accident simulation in a nuclear fusion plant

    NASA Astrophysics Data System (ADS)

    Camplani, M.; Malizia, A.; Gelfusa, M.; Barbato, F.; Antonelli, L.; Poggi, L. A.; Ciparisse, J. F.; Salgado, L.; Richetta, M.; Gaudio, P.

    2016-01-01

    In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles' velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

  12. Image computing techniques to extrapolate data for dust tracking in case of an experimental accident simulation in a nuclear fusion plant.

    PubMed

    Camplani, M; Malizia, A; Gelfusa, M; Barbato, F; Antonelli, L; Poggi, L A; Ciparisse, J F; Salgado, L; Richetta, M; Gaudio, P

    2016-01-01

    In this paper, a preliminary shadowgraph-based analysis of dust particles re-suspension due to loss of vacuum accident (LOVA) in ITER-like nuclear fusion reactors has been presented. Dust particles are produced through different mechanisms in nuclear fusion devices, one of the main issues is that dust particles are capable of being re-suspended in case of events such as LOVA. Shadowgraph is based on an expanded collimated beam of light emitted by a laser or a lamp that emits light transversely compared to the flow field direction. In the STARDUST facility, the dust moves in the flow, and it causes variations of refractive index that can be detected by using a CCD camera. The STARDUST fast camera setup allows to detect and to track dust particles moving in the vessel and then to obtain information about the velocity field of dust mobilized. In particular, the acquired images are processed such that per each frame the moving dust particles are detected by applying a background subtraction technique based on the mixture of Gaussian algorithm. The obtained foreground masks are eventually filtered with morphological operations. Finally, a multi-object tracking algorithm is used to track the detected particles along the experiment. For each particle, a Kalman filter-based tracker is applied; the particles dynamic is described by taking into account position, velocity, and acceleration as state variable. The results demonstrate that it is possible to obtain dust particles' velocity field during LOVA by automatically processing the data obtained with the shadowgraph approach.

  13. Validating α-particle emission from 211At-labeled antibodies in single cells for cancer radioimmunotherapy using CR-39 plastic nuclear track detectors.

    PubMed

    Kodaira, Satoshi; Li, Huizi Keiko; Konishi, Teruaki; Kitamura, Hisashi; Kurano, Mieko; Hasegawa, Sumitaka

    2017-01-01

    Recently, 211At has received increasing attention as a potential radionuclide for cancer radioimmunotherapy. It is a α-particle emitter, which is extremely effective against malignant cells. We demonstrate a method to verify the efficiency of 211At-labeled trastuzumab antibodies (211At-trastuzumab) against HER2 antigens, which has not been determined for radioimmunotherapy. A CR-39 plastic nuclear detector is used for measuring the position and the linear energy transfer (LET) of individual 211At α- particle tracks. The tracks and 211At-trastuzumab-binding cells were co-visualized by using the geometric information recorded on the CR-39. HER2-positive human gastric cancer cells (NCI-N87), labelled with 211At-trastuzumab, were dropped on the centre of the CR-39 plate. Microscope images of the cells and the corresponding α-tracks acquired by position matching were obtained. In addition, 3.5 cm × 3.5 cm macroscopic images of the whole plate were acquired. The distribution of number of α-particles emitted from single cells suggests that 80% of the 211At-trastuzumab-binding cells emitted α-particles. It also indicates that the α-particles may strike the cells several times along their path. The track-averaged LET of the α-particles is evaluated to be 131 keV/μm. These results will enable quantitative evaluation of delivered doses to target cells, and will be useful for the in vitro assessment of 211At-based radioimmunotherapeutic agents.

  14. Coupled chemical reactions in dynamic nanometric confinement: V. The influence of Li+ and F- ions on etching of nuclear tracks in polymers

    NASA Astrophysics Data System (ADS)

    Fink, D.; Muñoz Hernandez, G.; Ruiz, N. L.; Vacik, J.; Hnatowicz, V.; García-Arellano, H.; Alfonta, L.; Kiv, A.

    2014-05-01

    Etching of continuous nuclear tracks in thin polymer foils from both sides is known to lead to the formation of double-conical nanopores. In this work and related ones we try to find out how this etching kinetics is modified when materials are added which react with each other upon their contact towards some new product that influences the etching. For that purpose we have chosen here Li+ and F- ions as the additions, which react with each other to form LiF precipitations. The coupled etching and precipitation kinetics is recorded by measuring the electrical current that is transmitted through the foils upon application of a low-frequency alternating sinusoidal voltage. Depending on the etchant concentrations, the etching temperature and the time of Li+ and F- addition, different effects are found that range from (a) no alteration of the transmitted current at all, via (b) the emergence of an alternating current with a temperature-dependent amplitude, and (c) the complete vanishing of any transmitted current at all, towards (d) chaotic transmitted current histories with phases with strong current spike emission and (e) rather quiet phases, alternating with each other in a rather unsystematic way. The observed effects are ascribed to (a) the enhanced penetration efficiency of both the Li+ and F- ions through the polymeric bulk and/or latent ion tracks after the removal of the polymer's protective surface layer by the etchant, (b) the high mobility of preferentially the F- ions within the polymer, (c) the LiF precipitation within the polymer or on its surface upon encounter of Li+ and F- ions, (d) the nanofluidic properties of narrow etched tracks covered with Li+ ions on the wall surfaces and F- ions beyond, and/or (e) the formation of LiF membranes within the etched tracks.

  15. Fast track, dynein-dependent nuclear targeting of human immunodeficiency virus Vpr protein; impaired trafficking in a clinical isolate

    SciTech Connect

    Caly, Leon; Kassouf, Vicki T.; Moseley, Gregory W.; Diefenbach, Russell J.; Cunningham, Anthony L.; Jans, David A.

    2016-02-12

    Nuclear import of the accessory protein Vpr is central to infection by human immunodeficiency virus (HIV). We previously identified the Vpr F72L mutation in a HIV-infected, long-term non-progressor, showing that it resulted in reduced Vpr nuclear accumulation and altered cytoplasmic localisation. Here we demonstrate for the first time that the effects of nuclear accumulation of the F72L mutation are due to impairment of microtubule-dependent-enhancement of Vpr nuclear import. We use high resolution imaging approaches including fluorescence recovery after photobleaching and other approaches to document interaction between Vpr and the dynein light chain protein, DYNLT1, and impaired interaction of the F72L mutant with DYNLT1. The results implicate MTs/DYNLT1 as drivers of Vpr nuclear import and HIV infection, with important therapeutic implications. - Highlights: • HIV-1 Vpr utilizes the microtubule network to traffic towards the nucleus. • Mechanism relies on interaction between Vpr and dynein light chain protein DYNLT1. • Long-term non-progressor derived mutation (F72L) impairs this interaction. • Key residues in the vicinity of F72 contribute to interaction with DYNLT1.

  16. Deployable Plume and Aerosol Release Prediction and Tracking System. Nuclear Non-Proliferation Task 1. Final Report

    SciTech Connect

    Kleppe, John; Norris, William; Etezadi, Mehdi

    2006-07-19

    This contract was awarded in response to a proposal in which a deployable plume and aerosol release prediction and tracking system would be designed, fabricated, and tested. The system would gather real time atmospheric data and input it into a real time atmospheric model that could be used for plume predition and tracking. The system would be able to be quickly deployed by aircraft to points of interest or positioned for deployment by vehicles. The system would provide three dimensional (u, v, and w) wind vector data, inversion height measurements, surface wind information, classical weather station data, and solar radiation. The on-board real time computer model would provide the prediction of the behavior of plumes and released aerosols.

  17. Charge, energy and LET spectra of high LET primary and secondary particles in CR-39 plastic nuclear track detectors of the P0006 experiment

    NASA Technical Reports Server (NTRS)

    Csige, I.; Frigo, L. A.; Benton, E. V.; Oda, K.

    1995-01-01

    We have measured the charge, energy and linear energy transfer (LET) spectra of about 800 high LET (LET(sub infinity) H2O greater than 50 keV/micron) particles in CR-39 plastic nuclear track detectors in the P0006 experiment of LDEF. Primary particles with residual range at the reference surface greater than about 2 microns and secondary particles produced in the detector material with total range greater than about 4 microns were measured. We have used a multi-etch technique and an internal calibration to identify and measure the energy of the particles at the reference surface. The LET spectrum was obtained from the charge and energy distribution of the particles.

  18. Dissociation of {sup 10}C nuclei in a track nuclear emulsion at an energy of 1.2 GeV per nucleon

    SciTech Connect

    Mamatkulov, K. Z.; Kattabekov, R. R.; Alikulov, S. S.; Artemenkov, D. A.; Bekmirzaev, R. N.; Bradnova, V.; Zarubin, P. I. Zarubina, I. G.; Kondratieva, N. V.; Kornegrutsa, N. K.; Krivenkov, D. O.; Malakhov, A. I.; Olimov, K.; Peresadko, N. G.; Polukhina, N. G.; Rukoyatkin, P. A.; Rusakova, V. V.; Stanoeva, R.; Kharlamov, S. P.

    2013-10-15

    The charge topology in the fragmentation of {sup 10}C nuclei in a track nuclear emulsion at an energy of 1.2 GeV per nucleon is studied. In the coherent dissociation of {sup 10}C nuclei, about 82% of events are associated with the channel {sup 10}C {yields} 2{alpha}+ 2p. The angular distributions and correlations of product fragments are presented for this channel. It is found that among {sup 10}C {yields} 2{alpha}+ 2p events, about 30% are associated with the process in which dissociation through the ground state of the unstable {sup 9}Be{sub g.s.} nucleus is followed by {sup 8}Be{sub g.s.} + p decays.

  19. Mapping of the thermal neutron distribution in the lead block assembly of the PS-211 experiment at CERN, using thermoluminescence and nuclear track detectors.

    PubMed

    Savvidis, E; Eleftheriadis, C A; Kitis, G

    2002-01-01

    The main purpose of the TARC (Transmutation by Adiabatic Resonance Crossing) experiment (PS-211), was to demonstrate the possibility to destroy efficiently Long-Lived Fission Fragments (LLFF) in Accelerator Driven Systems (ADS). The experimental set-up which consisted of a lead block with dimensions 3.3 x 3.3 x 3 m3, was installed in a CERN Proton Synchrotron (PS) beam line. The proton beam at 2.5 GeV/c and 3.5 GeV/c, was incident in the centre of the lead block assembly producing neutrons via spallation reactions. In this study, neutron flux measurements are presented in the lead block assembly using thermoluminescence and nuclear track detectors. The results are in good agreement with Monte Carlo calculations as well as with the results of the other methods used in the framework of the TARC experiment.

  20. Changes in the thermal properties of PADC film-based nuclear track detectors produced by high doses of γ-radiation

    NASA Astrophysics Data System (ADS)

    Saad, A. F.; Saad, Noura; Abdalla, Y. K.

    2014-04-01

    Irradiation effects on the thermal properties of poly allyl diglycol carbonate (PADC) polymer-based nuclear track detectors (in the form of CR-39) have been investigated. PADC films were exposed to γ-rays at high doses ranging from 5.0 × 105 to 1.0 × 106 Gy. The induced modifications were analyzed by means of thermogravimetric analysis, which indicated that the PADC film decomposed in three main stages. The activation energy for thermal decomposition was determined using a type of Arrhenius equation based on the TGA experimental results. This study presents quantitative results showing that the exposed PADC films do not undergo continual further degradation from high-energy γ-photons with increase in dose. The experimental results also provide insight into the specific property changes induced by γ-rays, which may be of use for industrial applications.

  1. Calibration of the Politrack® system based on CR39 solid-state nuclear track detectors for passive indoor radon concentration measurements.

    PubMed

    Kropat, G; Baechler, S; Bailat, C; Barazza, F; Bochud, F; Damet, J; Meyer, N; Palacios Gruson, M; Butterweck, G

    2015-11-01

    Swiss national requirements for measuring radon gas exposures demand a lower detection limit of 50 kBq h m(-3), representing the Swiss concentration average of 70 Bq m(-3) over a 1-month period. A solid-state nuclear track detector (SSNTD) system (Politrack, Mi.am s.r.l., Italy) has been acquired to fulfil these requirements. This work was aimed at the calibration of the Politrack system with traceability to international standards and the development of a procedure to check the stability of the system. A total of 275 SSNTDs was exposed to 11 different radon exposures in the radon chamber of the Secondary Calibration Laboratory at the Paul Scherrer Institute, Switzerland. The exposures ranged from 50 to 15000 kBq h m(-3). For each exposure of 20 detectors, 5 SSNTDs were used to monitor possible background exposures during transport and storage. The response curve and the calibration factor of the whole system were determined using a Monte Carlo fitting procedure. A device to produce CR39 samples with a reference number of tracks using a (241)Am source was developed for checking the long-term stability of the Politrack system. The characteristic limits for the detection of a possible system drift were determined following ISO Standard 11929. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Ultraviolet radiation-induced modifications of the optical and registration properties of a CR-39 nuclear track detector

    NASA Astrophysics Data System (ADS)

    Saad, A. F.; Al-Faitory, N. M.; Hussein, M.; Mohamed, R. A.

    2015-09-01

    The UV-VIS (ultraviolet-visible) spectra and etching characteristics of poly allyl diglycol carbonate (PADC, a form of the CR-39 polymer) detector films after exposure to UV radiation for various times have been studied. Etching experiments were carried out on the UV-exposed CR-39 detectors after alpha particle and fission-fragment irradiation using a 252Cf source. The bulk and track etch rates were measured using the alpha and fission-fragment track diameters, and the sensitivity and the detection efficiency were also determined. The optical band gap for both indirect and direct transitions was calculated based on the absorption edge of the UV spectra of the pristine and variously UV-exposed detectors. The optical band gap evidently indicates a gradual change in the optical properties of the CR-39 detector that is induced by the UV radiation. This study shows that the UV-exposed CR-39 detectors were demonstrated to be highly sensitive to alpha particles, but proved to be somewhat less sensitive to the fission fragments.

  3. Gamma ray induced modifications in cellulose triacetate polymer used as a solid-state nuclear track detector

    NASA Astrophysics Data System (ADS)

    Prasher, Sangeeta; Kumar, Mukesh; Singh, Surinder

    2017-07-01

    The effects of gamma radiations from a 60Co source on the easily available overhead projector transparency have been analyzed. FTIR and UV-VIS spectra of the polymer before and after irradiation have been recorded and from the spectral data some modifications in the properties have been investigated. The band gap energy has been calculated from the UV-VIS spectral data and it was found to remain constant up to a gamma dose of 103krad and decreases thereafter. FTIR studies reveal the fact that there is a generation of CO2 and -OH groups at higher doses, which is further confirmed from the decarboxylation mechanism in esters. Aliphatic C-H stretching intensity has also been found to increase with gamma dose. The changes in track registration properties of the polymer alongwith the activation energies for bulk and track etch rates have been observed. The etch rates have been observed to increase, which can accounts for the presence of oxygen. It is found that overhead projector transparency is a highly radiation resistant polymer as it is influenced to a very little extent up to the dose of 103krad. The changes are pronounced at higher gamma doses of the order of 5×104 and 105krad.

  4. Measurements and calculations of the Coulomb cross section for the production of direct electron pairs by energetic heavy nuclei in nuclear track emulsion

    NASA Technical Reports Server (NTRS)

    Derrickson, J. H.; Eby, P. B.; Fountain, W. F.; Parnell, T. A.; Dong, B. L.; Gregory, J. C.; Takahashi, Y.; King, D. T.

    1988-01-01

    Measurements and theoretical predictions of the Coulomb cross section for the production of direct electron pairs by heavy ions in emulsion have been performed. Nuclear track emulsions were exposed to the 1.8 GeV/amu Fe-56 beam at the Lawrence Berkeley Laboratory bevalac and to the 60 and 200 GeV/amu O-16 and the 200 GeV/amu S-32 beam at the European Center for Nuclear Research Super Proton Synchrotron modified to accelerate heavy ions. The calculations combine the Weizsacker-Williams virtual quanta method applicable to the low-energy transfers and the Kelner-Kotov relativistic treatment for the high-energy transfers. Comparison of the measured total electron pair yield, the energy transfer distribution, and the emission angle distribution with theoretical predictions revealed a discrepancy in the frequency of occurrence of the low-energy pairs (less than or = 10 MeV). The microscope scanning criteria used to identify the direct electron pairs is described and efforts to improve the calculation of the cross section for pair production are also discussed.

  5. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    NASA Astrophysics Data System (ADS)

    Kulkarni, A.; Ha, S.; Joshirao, P.; Manchanda, V.; Bak, M. S.; Kim, T.

    2015-06-01

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO3)4 ṡ 5H2O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  6. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector

    SciTech Connect

    Kulkarni, A.; Bak, M. S. E-mail: moonsoo@skku.edu; Ha, S.; Joshirao, P.; Manchanda, V.; Kim, T. E-mail: moonsoo@skku.edu

    2015-06-15

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO{sub 3}){sub 4} ⋅ 5H{sub 2}O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  7. Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector.

    PubMed

    Kulkarni, A; Ha, S; Joshirao, P; Manchanda, V; Bak, M S; Kim, T

    2015-06-01

    A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO3)4 ⋅ 5H2O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

  8. Results from the characterisation of Advanced GAmma Tracking Array prototype detectors and their consequences for the next-generation nuclear physics spectrometer

    NASA Astrophysics Data System (ADS)

    Dimmock, M. R.; Boston, A. J.; Boston, H. C.; Cresswell, J. R.; Nelson, L.; Nolan, P.; Rigby, S.; Unsworth, C.; Lazarus, I.; Simpson, J.; Medina, P.; Parisel, C.; Santos, C.

    2007-09-01

    The Advanced GAmma Tracking Array (AGATA) is a European project that is aiming to construct a complete 4π High Purity Germanium (HPGe) gamma-ray spectrometer for nuclear structure studies at future Radioactive Ion Beam (RIB) Facilities. The proposed array will utilise digital electronics, Pulse Shape Analysis (PSA) and Gamma-Ray Tracking (GRT) algorithms, to overcome the limited efficiencies encountered by current Escape Suppressed Spectrometers (ESS), whilst maintaining the high Peak-to-Total ratio. Two AGATA symmetrical segmented Canberra Eurisys (CE) prototype HPGe detectors have been tested at the University of Liverpool. A highly collimated Cs-137 (662keV) beam was raster scanned across each detector and data were collected in both singles and coincidence modes. The charge sensitive preamplifier output pulse shapes from all 37 channels (one for each of the 36 segments and one for the centre contact) were digitised and stored for offline analysis. The shapes of the real charge and image charge pulses have been studied to give detailed information on the position dependent response of each detector. 1mm position sensitivity has been achieved with the parameterisation of average pulse shapes, calculated from data collected with each of the detectors. The coincidence data has also been utilised to validate the electric field simulation code Multi Geometry Simulation (MGS). The precisely determined 3D interaction positions allow the comparison of experimental pulse shapes from single site interactions with those generated by the simulation. It is intended that the validated software will be used to calculate a basis data set of pulse shapes for the array, from which any interaction site can be determined through a χ2 minimisation of the digitized pulse with linear combinations of basis pulseshapes. The results from this partial validation, along with those from the investigation into the position sensitivity of each detector are presented.

  9. SU-E-T-98: Towards Cell Nucleus Microdosimetry: Construction of a Confocal Laser-Scanning Fluorescence Microscope to Readout Fluorescence Nuclear Track Detectors (FNTDs).

    PubMed

    McFadden, C; Bartz, J; Akselrod, M; Sawakuchi, G

    2012-06-01

    To construct a custom confocal laser scanning microscope (CLSM) capable of resolving individual proton tracks in the volume of an Al2 O3 :C,Mg fluorescent nuclear track detector (FNTD). The spatial resolution of the FNTD technique is at the sub-micrometer scale. Therefore the FNTD technique has the potential to perform radiation measurements at the cell nucleus scale. The crystal volume of an FNTD contains defects which become fluorescent F2(+) centers after trapping delta electrons from ionizing radiation. These centers have an absorption band centered at 620 nm and an emission band in the near infrared. Events of energy deposition in the crystal are read-out using a CLSM with sub-micrometer spatial resolution. Excitation light from a 635 nm laser is focused in the crystal volume by an objective lens. Fluorescence is collected back through the same path, filtered through a dichroic mirror, and focused through a small pinhole onto an avalanche photodiode. Lateral scanning of the focal point is performed with a scanning mirror galvanometer, and axial scanning is performed using a stepper-motor stage. Control of electronics and image acquisition was performed using a custom built LabVIEW VI and further image processing was done using Java. The system was used to scan FNTDs exposed to a 6 MV x-ray beam and an unexposed FNTD. Fluorescence images above the unexposed background were obtained at scan depths ranging from 5 - 10 micrometer below the crystal surface using a 100 micrometer pinhole size. Further work needs to be done to increase the resolution and the signal to noise ratio of the images so that energy deposition events may be identified more easily. Natural Sciences and Engineering Research Council of Canada. © 2012 American Association of Physicists in Medicine.

  10. Microfluidic device with integrated microfilter of conical-shaped holes for high efficiency and high purity capture of circulating tumor cells

    NASA Astrophysics Data System (ADS)

    Tang, Yadong; Shi, Jian; Li, Sisi; Wang, Li; Cayre, Yvon E.; Chen, Yong

    2014-08-01

    Capture of circulating tumor cells (CTCs) from peripheral blood of cancer patients has major implications for metastatic detection and therapy analyses. Here we demonstrated a microfluidic device for high efficiency and high purity capture of CTCs. The key novelty of this approach lies on the integration of a microfilter with conical-shaped holes and a micro-injector with cross-flow components for size dependent capture of tumor cells without significant retention of non-tumor cells. Under conditions of constant flow rate, tumor cells spiked into phosphate buffered saline could be recovered and then cultured for further analyses. When tumor cells were spiked in blood of healthy donors, they could also be recovered at high efficiency and high clearance efficiency of white blood cells. When the same device was used for clinical validation, CTCs could be detected in blood samples of cancer patients but not in that of healthy donors. Finally, the capture efficiency of tumor cells is cell-type dependent but the hole size of the filter should be more closely correlated to the nuclei size of the tumor cells. Together with the advantage of easy operation, low-cost and high potential of integration, this approach offers unprecedented opportunities for metastatic detection and cancer treatment monitoring.

  11. Microfluidic device with integrated microfilter of conical-shaped holes for high efficiency and high purity capture of circulating tumor cells.

    PubMed

    Tang, Yadong; Shi, Jian; Li, Sisi; Wang, Li; Cayre, Yvon E; Chen, Yong

    2014-08-13

    Capture of circulating tumor cells (CTCs) from peripheral blood of cancer patients has major implications for metastatic detection and therapy analyses. Here we demonstrated a microfluidic device for high efficiency and high purity capture of CTCs. The key novelty of this approach lies on the integration of a microfilter with conical-shaped holes and a micro-injector with cross-flow components for size dependent capture of tumor cells without significant retention of non-tumor cells. Under conditions of constant flow rate, tumor cells spiked into phosphate buffered saline could be recovered and then cultured for further analyses. When tumor cells were spiked in blood of healthy donors, they could also be recovered at high efficiency and high clearance efficiency of white blood cells. When the same device was used for clinical validation, CTCs could be detected in blood samples of cancer patients but not in that of healthy donors. Finally, the capture efficiency of tumor cells is cell-type dependent but the hole size of the filter should be more closely correlated to the nuclei size of the tumor cells. Together with the advantage of easy operation, low-cost and high potential of integration, this approach offers unprecedented opportunities for metastatic detection and cancer treatment monitoring.

  12. Soil gas radon-thoron monitoring in Dharamsala area of north-west Himalayas, India using solid state nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Kumar, Gulshan; Kumar, Arvind; Walia, Vivek; Kumar, Jitender; Gupta, Vikash; Yang, Tsanyao Frank; Singh, Surinder; Bajwa, Bikramjit Singh

    2013-10-01

    The study described here is based on the measurements of soil gas radon-thoron concentrations performed at Dharamsala region of north-west (NW) Himalayas, India. The study area is tectonically and environmentally significant and shows the features of ductile shear zone due to the presence of distinct thrust planes. Solid state nuclear track detectors (LR-115 films) have been used for the soil gas radon-thoron monitoring. Twenty five radon-thoron discriminators with LR-115 films were installed in the borehole of about 50 cm in the study areas. The recorded radon concentration varies from 1593 to 13570 Bq/m3 with an average value of 5292 Bq/m3. The recorded thoron concentration varies from 223 to 2920 Bq/m3 with an average value of 901 Bq/m3. The anomalous value of radon-thoron has been observed near to the faults like main boundary thrust (MBT and MBT2) as well as neotectonic lineaments in the region.

  13. Multiscale study of the boron and carbon behavior in the fracture zone of the rapidly quenched nickel-based superalloy by the nuclear physics methods of the track and activation autoradiography

    NASA Astrophysics Data System (ADS)

    Shulga, A. V.

    2016-04-01

    The results of the study of the fracture zone of the rapidly quenched nickel-based superalloy after tensile tests are presented. The main attention was attended to the multiscale investigation of boron and carbon distribution in the area of the cracks propagation by the direct nuclear physics methods of the track and activation autoradiography. Tensile tests were performed at the temperatures up to 1150 °C. The nuclear reactor MEPhI IRT-2000 and cyclotron were applied for the autoradiography studies. Significant depleting of boron in the fracture zone which was revealed can be explained due to the intensive moving of the dislocation.

  14. Development of a rapid and sensitive method combining a cellulose ester microfilter and a real-time quantitative PCR assay to detect Campylobacter jejuni and Campylobacter coli in 20 liters of drinking water or low-turbidity waters.

    PubMed

    Tissier, Adeline; Denis, Martine; Hartemann, Philippe; Gassilloud, Benoît

    2012-02-01

    Investigations of Campylobacter jejuni and Campylobacter coli in samples of drinking water suspected of being at the origin of an outbreak very often lead to negative results. One of the reasons for this failure is the small volume of water typically used for detecting these pathogens (10 to 1,000 ml). The efficiencies of three microfilters and different elution procedures were determined using real-time quantitative PCR to propose a procedure allowing detection of Campylobacter in 20 liters of drinking water or low-turbidity water samples. The results showed that more than 80% of the bacteria inoculated in 1 liter of drinking water were retained on each microfilter. An elution with a solution containing 3% beef extract, 0.05 M glycine at pH 9, combined with direct extraction of the bacterial genomes retained on the cellulose ester microfilter, allowed recovery of 87.3% (±22% [standard deviation]) of Campylobacter per 1 liter of tap water. Recoveries obtained from 20-liter volumes of tap water spiked with a C. coli strain were 69.5% (±10.3%) and 78.5% (±15.1%) for 91 CFU and 36 CFU, respectively. Finally, tests performed on eight samples of 20 liters of groundwater collected from an alluvial well used for the production of drinking water revealed the presence of C. jejuni and C. coli genomes, whereas no bacteria were detected with the normative culture method in volumes ranging from 10 to 1,000 ml. In the absence of available epidemiological data and information on bacterial viability, these last results indicate only that the water resource is not protected from contamination by Campylobacter.

  15. Development of a Rapid and Sensitive Method Combining a Cellulose Ester Microfilter and a Real-Time Quantitative PCR Assay To Detect Campylobacter jejuni and Campylobacter coli in 20 Liters of Drinking Water or Low-Turbidity Waters

    PubMed Central

    Tissier, Adeline; Denis, Martine; Hartemann, Philippe

    2012-01-01

    Investigations of Campylobacter jejuni and Campylobacter coli in samples of drinking water suspected of being at the origin of an outbreak very often lead to negative results. One of the reasons for this failure is the small volume of water typically used for detecting these pathogens (10 to 1,000 ml). The efficiencies of three microfilters and different elution procedures were determined using real-time quantitative PCR to propose a procedure allowing detection of Campylobacter in 20 liters of drinking water or low-turbidity water samples. The results showed that more than 80% of the bacteria inoculated in 1 liter of drinking water were retained on each microfilter. An elution with a solution containing 3% beef extract, 0.05 M glycine at pH 9, combined with direct extraction of the bacterial genomes retained on the cellulose ester microfilter, allowed recovery of 87.3% (±22% [standard deviation]) of Campylobacter per 1 liter of tap water. Recoveries obtained from 20-liter volumes of tap water spiked with a C. coli strain were 69.5% (±10.3%) and 78.5% (±15.1%) for 91 CFU and 36 CFU, respectively. Finally, tests performed on eight samples of 20 liters of groundwater collected from an alluvial well used for the production of drinking water revealed the presence of C. jejuni and C. coli genomes, whereas no bacteria were detected with the normative culture method in volumes ranging from 10 to 1,000 ml. In the absence of available epidemiological data and information on bacterial viability, these last results indicate only that the water resource is not protected from contamination by Campylobacter. PMID:22138985

  16. A performance test of a new high-surface-quality and high-sensitivity CR-39 plastic nuclear track detector - TechnoTrak

    NASA Astrophysics Data System (ADS)

    Kodaira, S.; Morishige, K.; Kawashima, H.; Kitamura, H.; Kurano, M.; Hasebe, N.; Koguchi, Y.; Shinozaki, W.; Ogura, K.

    2016-09-01

    We have studied the performance of a newly-commercialized CR-39 plastic nuclear track detector (PNTD), ;TechnoTrak;, in energetic heavy ion measurements. The advantages of TechnoTrak are derived from its use of a purified CR-39 monomer to improve surface quality combined with an antioxidant to improve sensitivity to low-linear-energy-transfer (LET) particles. We irradiated these detectors with various heavy ions (from protons to krypton) with various energies (30-500 MeV/u) at the heavy ion accelerator facilities in the National Institute of Radiological Sciences (NIRS). The surface roughness after chemical etching was improved to be 59% of that of the conventional high-sensitivity CR-39 detector (HARZLAS/TD-1). The detectable dynamic range of LET was found to be 3.5-600 keV/μm. The LET and charge resolutions for three ions tested ranged from 5.1% to 1.5% and 0.14 to 0.22 c.u. (charge unit), respectively, in the LET range of 17-230 keV/μm, which represents an improvement over conventional products (HARZLAS/TD-1 and BARYOTRAK). A correction factor for the angular dependence was determined for correcting the LET spectrum in an isotropic radiation field. We have demonstrated the potential of TechnoTrak, with its two key features of high surface quality and high sensitivity to low-LET particles, to improve automatic analysis protocols in radiation dosimetry and various other radiological applications.

  17. Nuclear tracks in lunar samples

    NASA Technical Reports Server (NTRS)

    Price, P. B.

    1971-01-01

    An attempt is made to relate the appearance of an etched tract to the atomic number and velocity of the ion that left it using 10 MeV/nucleon Kr beams and 6 MeV/nucleon Zn beams. It was found that the etching rate along a tract in minerals and glass is a monototonic function of ionization rate thus, making particle identification possible. Results show the following were present in lunar samples: superheavy elements, cosmic rays with z greater than 26, and solar flare particles in Surveyor glass.

  18. Nuclear Track Detection in School.

    ERIC Educational Resources Information Center

    Mold, P.; Bull, R. K.

    1980-01-01

    Describes experiments using solid state detectors in modern physics courses. The apparatus involved is simple and inexpensive, avoiding costly electronics, and the very high efficiency of plastic detectors in particular makes them ideally suited for work with very weak radioactive sources. (Author/SK)

  19. Nuclear Track Detection in School.

    ERIC Educational Resources Information Center

    Mold, P.; Bull, R. K.

    1980-01-01

    Describes experiments using solid state detectors in modern physics courses. The apparatus involved is simple and inexpensive, avoiding costly electronics, and the very high efficiency of plastic detectors in particular makes them ideally suited for work with very weak radioactive sources. (Author/SK)

  20. MATERIAL TRACKING USING LANMAS

    SciTech Connect

    Armstrong, F.

    2010-06-07

    LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

  1. Spoilage of Microfiltered and Pasteurized Extended Shelf Life Milk Is Mainly Induced by Psychrotolerant Spore-Forming Bacteria that often Originate from Recontamination

    PubMed Central

    Doll, Etienne V.; Scherer, Siegfried; Wenning, Mareike

    2017-01-01

    Premature spoilage and varying product quality due to microbial contamination still constitute major problems in the production of microfiltered and pasteurized extended shelf life (ESL) milk. Spoilage-associated bacteria may enter the product either as part of the raw milk microbiota or as recontaminants in the dairy plant. To identify spoilage-inducing bacteria and their routes of entry, we analyzed end products for their predominant microbiota as well as the prevalence and biodiversity of psychrotolerant spores in bulk tank milk. Process analyses were performed to determine the removal of psychrotolerant spores at each production step. To detect transmission and recontamination events, strain typing was conducted with isolates obtained from all process stages. Microbial counts in 287 ESL milk packages at the end of shelf life were highly diverse ranging from <1 to 7.9 log cfu/mL. In total, 15% of samples were spoiled. High G+C Gram-positive bacteria were the most abundant taxonomic group, but were responsible for only 31% of spoilage. In contrast, psychrotolerant spores were isolated from 55% of spoiled packages. In 90% of samples with pure cultures of Bacillus cereus sensu lato and Paenibacillus spp., counts exceeded 6 log cfu/mL. In bulk tank milk, the concentration of psychrotolerant spores was low, accounting for merely 0.5 ± 0.8 MPN/mL. Paenibacillus amylolyticus/xylanexedens was by far the most dominant species in bulk tank milk (48% of all isolates), but was never detected in ESL milk, pointing to efficient removal during manufacturing. Six large-scale process analyses confirmed a high removal rate for psychrotolerant spores (reduction by nearly 4 log-units). B. cereus sensu lato, on the contrary, was frequently found in spoiled end products, but was rarely detected in bulk tank milk. Due to low counts in bulk tank samples and efficient spore removal during production, we suggest that shelf life is influenced only to a minor extent by raw

  2. Track recording plastic compositions

    NASA Technical Reports Server (NTRS)

    Tarle, Gregory (Inventor)

    1983-01-01

    Improved nuclear track recording plastic compositions are provided which exhibit greatly decreased surface roughness when etched to produce visible tracks of energetic nuclear particles which have passed into and/or through said plastic. The improved compositions incorporate a small quantity of a phthalic acid ester into the major plastic component which is derived from the polymerization of monomeric di-ethylene glycol bis allyl carbonate. Di-substituted phthalic acid esters are preferred as the added component, with the further perference that the ester substituent has a chain length of 2 or more carbon atoms. The inclusion of the phthalic acid ester to an extent of from about 1-2% by weight of the plastic compositions is sufficient to drastically reduce the surface roughness ordinarily produced when the track recording plastic is contacted by etchants.

  3. ST-segment elevation in the recovery phase of nuclear exercise stress test with ⁹⁹mTc-sestamibi in a patient with critical RCA stenosis and subtle systolic dysfunction in speckle tracking imaging.

    PubMed

    Piszczek, Stanislaw; Dziuk, Miroslaw; Mazurek, Andrzej; Krzesiński, Paweł; Jaguś-Jamiola, Agnieszka; Ryczek, Robert; Tkaczewski, Konrad; Skrobowski, Andrzej; Cwetsch, Andrzej

    2012-04-24

    An asymptomatic Caucasian male patient underwent coronary artery disease diagnostics. Standard exercise treadmill test was inconclusive, and Holter ECG study didn't show any significant abnormalities. Considering the high risk of ischemic heart disease nuclear exercise stress test was performed,which revealed ST-segment elevation in the recovery phase of the treadmill exercise test. Single photon emission computed tomography (SPECT/CT) showed myocardial perfusion abnormalities in the inferior and lateral walls of the left ventricle. Furthermore,speckle tracking imaging showed subtle left ventricle dysfunction. Finally critical stenosis in the second segment of right coronary artery was diagnosed in coronary angiography.

  4. CR-39 track detector calibration for H, He, and C ions from 0.1-0.5 MeV up to 5 MeV for laser-induced nuclear fusion product identification

    SciTech Connect

    Baccou, C. Yahia, V.; Labaune, C.; Depierreux, S.; Neuville, C.; Goyon, C.; Consoli, F.; De Angelis, R.; Ducret, J. E.; Boutoux, G.; Rafelski, J.

    2015-08-15

    Laser-accelerated ion beams can be used in many applications and, especially, to initiate nuclear reactions out of thermal equilibrium. We have experimentally studied aneutronic fusion reactions induced by protons accelerated by the Target Normal Sheath Acceleration mechanism, colliding with a boron target. Such experiments require a rigorous method to identify the reaction products (alpha particles) collected in detectors among a few other ion species such as protons or carbon ions, for example. CR-39 track detectors are widely used because they are mostly sensitive to ions and their efficiency is near 100%. We present a complete calibration of CR-39 track detector for protons, alpha particles, and carbon ions. We give measurements of their track diameters for energy ranging from hundreds of keV to a few MeV and for etching times between 1 and 8 h. We used these results to identify alpha particles in our experiments on proton-boron fusion reactions initiated by laser-accelerated protons. We show that their number clearly increases when the boron fuel is preformed in a plasma state.

  5. CR-39 track detector calibration for H, He, and C ions from 0.1-0.5 MeV up to 5 MeV for laser-induced nuclear fusion product identification.

    PubMed

    Baccou, C; Yahia, V; Depierreux, S; Neuville, C; Goyon, C; Consoli, F; De Angelis, R; Ducret, J E; Boutoux, G; Rafelski, J; Labaune, C

    2015-08-01

    Laser-accelerated ion beams can be used in many applications and, especially, to initiate nuclear reactions out of thermal equilibrium. We have experimentally studied aneutronic fusion reactions induced by protons accelerated by the Target Normal Sheath Acceleration mechanism, colliding with a boron target. Such experiments require a rigorous method to identify the reaction products (alpha particles) collected in detectors among a few other ion species such as protons or carbon ions, for example. CR-39 track detectors are widely used because they are mostly sensitive to ions and their efficiency is near 100%. We present a complete calibration of CR-39 track detector for protons, alpha particles, and carbon ions. We give measurements of their track diameters for energy ranging from hundreds of keV to a few MeV and for etching times between 1 and 8 h. We used these results to identify alpha particles in our experiments on proton-boron fusion reactions initiated by laser-accelerated protons. We show that their number clearly increases when the boron fuel is preformed in a plasma state.

  6. CR-39 track detector calibration for H, He, and C ions from 0.1-0.5 MeV up to 5 MeV for laser-induced nuclear fusion product identification

    NASA Astrophysics Data System (ADS)

    Baccou, C.; Yahia, V.; Depierreux, S.; Neuville, C.; Goyon, C.; Consoli, F.; De Angelis, R.; Ducret, J. E.; Boutoux, G.; Rafelski, J.; Labaune, C.

    2015-08-01

    Laser-accelerated ion beams can be used in many applications and, especially, to initiate nuclear reactions out of thermal equilibrium. We have experimentally studied aneutronic fusion reactions induced by protons accelerated by the Target Normal Sheath Acceleration mechanism, colliding with a boron target. Such experiments require a rigorous method to identify the reaction products (alpha particles) collected in detectors among a few other ion species such as protons or carbon ions, for example. CR-39 track detectors are widely used because they are mostly sensitive to ions and their efficiency is near 100%. We present a complete calibration of CR-39 track detector for protons, alpha particles, and carbon ions. We give measurements of their track diameters for energy ranging from hundreds of keV to a few MeV and for etching times between 1 and 8 h. We used these results to identify alpha particles in our experiments on proton-boron fusion reactions initiated by laser-accelerated protons. We show that their number clearly increases when the boron fuel is preformed in a plasma state.

  7. Beam emittance forming line of the CW race-track microtron of the institute of nuclear physics of Moscow State University (INP MSU)

    NASA Astrophysics Data System (ADS)

    Alimov, A. S.; Gevorkyan, V. G.; Gorbatov, Yu. I.; Gribov, I. V.; Ibadov, A. Kh.; Ishkhanov, B. S.; Korneenkov, V. A.; Lazutin, E. V.; Makulbekov, E. A.; Piskarev, I. M.; Platov, K. Yu.; Savitsky, A. B.; Shumakov, A. V.; Shvedunov, V. I.; Sorvin, V. M.; Tiunov, A. V.; Ushkanov, V. A.; Zinoviev, S. V.

    1989-06-01

    The transverse and longitudinal emittance forming line (EFL) of the race-track microtron of INP MSU is described. The work presents the principles of operation, parameters of EFL elements, description of rf power supply system and automated control system. The method of EFL tuning and experimental results are discussed.

  8. Kalman filter-based fast track reconstruction for charged particles in a Compressed Baryonic Matter experiment using parallel computing on a multicore server at the Laboratory of Information Technologies, Joint Institute for Nuclear Research

    NASA Astrophysics Data System (ADS)

    Ablyazimov, T. O.; Zyzak, M. V.; Ivanov, V. V.; Kisel, P. I.

    2015-05-01

    One of the main goals in the Compressed Baryonic Matter (CBM) experiment (GSI, Germany) is to find parameters of charged particle trajectories. An online full event reconstruction is planned to be carried out in this experiment, thus demanding fast algorithms be developed, which make the most of the capabilities of modern CPU and GPU architectures. This paper presents the results of an analysis of the Kalman filter-based track reconstruction for charged particles implemented by using various code parallelization methods. A multicore server located at the Laboratory of Information Technologies, Joint Institute for Nuclear Research (LIT JINR), with two CPU Intel Xeon X5660 processors and a GPU Nvidia GTX 480 video card is used.

  9. Measurement of 238U and 232Th in Petrol, Gas-oil and Lubricant Samples by Using Nuclear Track Detectors and Resulting Radiation Doses to the Skin of Mechanic Workers.

    PubMed

    Misdaq, M A; Chaouqi, A; Ouguidi, J; Touti, R; Mortassim, A

    2015-10-01

    Workers in repair shops of vehicles (cars, buses, truck, etc.) clean carburetors, check fuel distribution, and perform oil changes and greasing. To explore the exposure pathway of (238)U and (232)Th and its decay products to the skin of mechanic workers, these radionuclides were measured inside petrol, gas-oil, and lubricant material samples by means of CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs), and corresponding annual committed equivalent doses to skin were determined. The maximum total equivalent effective dose to skin due to the (238)U and (232)Th series from the application of different petrol, gas-oil, and lubricant samples by mechanic workers was found equal to 1.2 mSv y(-1) cm(-2).

  10. Derailing Tracking.

    ERIC Educational Resources Information Center

    Black, Susan

    1993-01-01

    Reviews recent research on student achievement, self-concept, and curriculum and instruction showing the ineffectiveness of tracking and ability grouping. Certain court rulings show that tracking violates the equal protection clause of the Fourteenth Amendment. Innovative alternatives include cooperative learning, mastery learning, peer tutoring,…

  11. Beyond Tracking.

    ERIC Educational Resources Information Center

    Bates, Percy; And Others

    1992-01-01

    On the surface, educational tracking may seem like a useful tool for allowing students to work at their own pace, and to avoid discouraging competition, but abuses of the tracking idea have arisen through biased placement practices that have denied equal access to education for minority students. The articles in this issue explore a number of…

  12. Rover tracks

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Tracks made by the Sojourner rover are visible in this image, taken by one of the cameras aboard Sojourner on Sol 3. The tracks represent the rover maneuvering towards the rock dubbed 'Barnacle Bill.' The rover, having exited the lander via the rear ramp, first traveled towards the right portion of the image, and then moved forward towards the left where Barnacle Bill sits. The fact that the rover was making defined tracks indicates that the soil is made up of particles on a micron scale.

    Mars Pathfinder was developed and managed by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration.

  13. Rover Tracks

    NASA Image and Video Library

    1997-07-07

    Tracks made by the Sojourner rover are visible in this image, taken by one of the cameras aboard Sojourner on Sol 3. The tracks represent the rover maneuvering towards the rock dubbed "Barnacle Bill." The rover, having exited the lander via the rear ramp, first traveled towards the right portion of the image, and then moved forward towards the left where Barnacle Bill sits. The fact that the rover was making defined tracks indicates that the soil is made up of particles on a micron scale. http://photojournal.jpl.nasa.gov/catalog/PIA00633

  14. On charged particle tracks in cellulose nitrate and Lexan

    NASA Technical Reports Server (NTRS)

    Benton, E. V.; Henke, R. P.

    1972-01-01

    Investigations were performed aimed at developing plastic nuclear track detectors into quantitative tools for recording and measuring multicharged, heavy particles. Accurate track etch rate measurements as a function of LET were performed for cellulose nitrate and Lexan plastic detectors. This was done using a variety of incident charged particle types and energies. The effect of aging of latent tracks in Lexan in different gaseous atmospheres was investigated. Range distributions of high energy N-14 particle bevatron beams in nuclear emulsion were measured. Investigation of charge resolution and Bragg peak measurements were carried out using plastic nuclear track detectors.

  15. Analysis of 3-dimentional track parameters from 2-dimensional images of etched tracks in solid polymeric track detectors

    NASA Astrophysics Data System (ADS)

    Paul, Sabyasachi; Tripathy, S. P.; Sarkar, P. K.

    2012-10-01

    An algorithm and a computer program (autoTRAK) are developed for rapid and precise estimation of track parameters in solid polymeric track detectors (SPTD). In this work, an effort is made to determine the 3-dimensional (3D) parameters such as depth (or length) and angle of the tracks, which are usually difficult to estimate from 2D images. The basic parameters such as diameter, major axis, minor axis, area, track density, etc. are also determined by the program precisely. The program is capable of selecting genuine tracks with precise tracing of track contours, segregating overlapped tracks and rejecting track-like unwanted objects. The algorithm is based on grey level analysis of the 2D images of etched nuclear tracks and is successfully tested for the analysis of alpha tracks in CR-39 detectors. The track depth values obtained by autoTRAK are found to match with those of other predictive codes. The details of the autoTRAK program and comparison of its output with those obtained using manual and automatic mode of other available image analyzing softwares, viz. ImageJ and AxioVision, are presented in the paper.

  16. Boulder Tracks

    NASA Image and Video Library

    2004-07-15

    15 July 2004 The arrows in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture point to three boulders that left trails behind them as they rolled down the lower parts of a meteor crater's wall. In two cases, the tracks can be resolved into a series of small depressions, indicating the variable shape of the boulder as it unevenly proceeded down the slope. These features are located near 18.4°N, 120.1°W. The 75 meter scale bar is about 246 feet long. Sunlight illuminates the scene from the lower left. http://photojournal.jpl.nasa.gov/catalog/PIA06450

  17. Boulder Track

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-408, 1 July 2003

    If a boulder rolls down a slope on an uninhabited planet, does it make a sound? While we do not know the sound made by a boulder rolling down a slope in the martian region of Gordii Dorsum, we do know that it made an impression. This full-resolution Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a series of depressions made on a dust-mantled slope as a boulder rolled down it, sometime in the recent past. The boulder track is located just right of center in this picture. The boulder sits at the end of the track. This picture was acquired in May 2003; it is located near 11.2oN, 147.8oW. North is toward the lower left, sunlight illuminates the scene from the right. The picture covers an area only 810 meters (about 886 yards) across.

  18. DOE R and D data tracking base

    SciTech Connect

    Horpedahl, L.; Brooks, M.

    2000-12-01

    This document consists of DOE R and D tracking information for the following topics: Stockpile Readiness Program; Stockpile Reduction Program; Enduring Stockpile Program; Future Stockpile Program; Archiving; Nuclear Component Assessment; Advanced Application; Validation and Verification; Distance and Distributed Computing; DOD Munitions; Performance Assessment; Physics; Los Alamos Meson Physics Facility/Los Alamos Neutron Science Center; Advanced Hydrodynamic Radiography; Systems Engineering; Advanced Manufacturing; Chemistry and Materials; High Explosives; Special Nuclear Mateirals; Tritium; Collaboration with ASCI; Numeric Environment for Weapons Simulation; Target Physics; Theory and Modeling; Target Development; Fabrication and Handling; Other ICF Activities; Development of Predictive Capabilities--Nuclear; Development of Diagnostic Tools--Nuclear; Process Development; and IPPD/Agile Manufacturing.

  19. Tracking system

    SciTech Connect

    Leroy, V. A.; Gaedtke, H. D.

    1985-10-15

    A system of tracking the sun each day of the year with compensation for changes in time of sunrise and time of sunset as well as sun declination on a day to day basis, declination being under control of a crank that makes one revolution per year. The equation of time is under control of a cam that also revolves once a year and resets the clock to reflect solar rather than mean solar time in order to properly follow the sun. The position of sun acquisition and loss are a function of the declination and the time is a function of the clock corrected via the cam for equation of time. Thus, when the declination is reset each day, it sets the position of acquisition and loss while the clock, now set for the change due to the equation of time, determines the time of acquisition and loss.

  20. Latest nuclear emulsion technology

    NASA Astrophysics Data System (ADS)

    Rokujo, Hiroki; Kawahara, Hiroaki; Komatani, Ryosuke; Morishita, Misaki; Nakano, Toshiyuki; Otsuka, Naoto; Yoshimoto, Masahiro

    2017-06-01

    Nuclear emulsion is a extremely high-resolution 3D tracking detector. Since the discovery of the pion by C.F. Powell et al. in 1946, experiments with nuclear emulsions have contributed to the development of particle physics. (e.g. the OPERA collaboration reported the discovery of νμ * ντ oscillations in appearance mode in 2015) The technology of nuclear emulsion still keeps making progress. Since 2010, we have introduced a system of nuclear emulsion gel production to our laboratory in Nagoya University, and have started self-development of the new gel, instead of from the photographic film companies. Moreover, a faster automated emulsion scanning system is developed. Its scanning speed reaches 4000 cm2/h, and the load for analyzing becomes more and more lighter. In this presentation, we report the status of nuclear emulsion technologies for cosmic ray experiments.

  1. On the Right Track.

    ERIC Educational Resources Information Center

    Bieber, Ed

    1983-01-01

    Suggests thinking of "tracks" as clues and using them as the focus of outdoor activities in the urban environment. Provides 24 examples of possible track activities, including: seeds on the ground (track of a nearby tree), litter (track of a litterbug), and peeling paint (track of weathering forces). (JN)

  2. On the Right Track.

    ERIC Educational Resources Information Center

    Bieber, Ed

    1983-01-01

    Suggests thinking of "tracks" as clues and using them as the focus of outdoor activities in the urban environment. Provides 24 examples of possible track activities, including: seeds on the ground (track of a nearby tree), litter (track of a litterbug), and peeling paint (track of weathering forces). (JN)

  3. Track Construction Manual.

    ERIC Educational Resources Information Center

    Banke, Ron; Di Gennaro, Guy; Ediger, Rick; Garner, Lanny; Hersom, Steve; Miller, Jack; Nemeth, Ron; Petrucelli, Jim; Sierks, Donna; Smith, Don; Swank, Kevin; West, Kevin

    This book establishes guidelines for the construction and maintenance of tracks by providing information for building new tracks or upgrading existing tracks. Subjects covered include running track planning and construction, physical layout, available surfaces, and maintenance. General track requirements and construction specifications are…

  4. Track structure in biological models.

    PubMed

    Curtis, S B

    1986-01-01

    High-energy heavy ions in the galactic cosmic radiation (HZE particles) may pose a special risk during long term manned space flights outside the sheltering confines of the earth's geomagnetic field. These particles are highly ionizing, and they and their nuclear secondaries can penetrate many centimeters of body tissue. The three dimensional patterns of ionizations they create as they lose energy are referred to as their track structure. Several models of biological action on mammalian cells attempt to treat track structure or related quantities in their formulation. The methods by which they do this are reviewed. The proximity function is introduced in connection with the theory of Dual Radiation Action (DRA). The ion-gamma kill (IGK) model introduces the radial energy-density distribution, which is a smooth function characterizing both the magnitude and extension of a charged particle track. The lethal, potentially lethal (LPL) model introduces lambda, the mean distance between relevant ion clusters or biochemical species along the track. Since very localized energy depositions (within approximately 10 nm) are emphasized, the proximity function as defined in the DRA model is not of utility in characterizing track structure in the LPL formulation.

  5. Cooperative Tracking for Persistent Littoral Undersea Surveillance

    DTIC Science & Technology

    2007-06-01

    Ballistic Missile boats (SSBNs) and Attack boats (SSNs). These nuclear submarines carried out three main missions. SSBNs went on strategic deterrent...patrols, hid- ing in the ocean and listening for commands to launch a retaliatory nuclear attack . SSNs tracked SSBNs and sought to kill them before any...retaliatory attack could be launched once the hot war had begun. SSNs also performed Intelligence, Surveillance and Reconnaissance (ISR) missions near

  6. Nuclear power and nuclear weapons

    SciTech Connect

    Vaughen, V.C.A.

    1983-01-01

    The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described.

  7. On the reproducibility of SSNTD track counting efficiency

    NASA Astrophysics Data System (ADS)

    Guedes O, S.; Hadler N, J. C.; Iunes, P. J.; Paulo, S. R.; Tello S, C. A.

    1998-12-01

    In this work, the influence of track density and chemical etching on the reproducibility of the track counting efficiency, ɛ0, in solid state nuclear track detectors (SSNTDs) is studied. This was performed by means of the analysis of CR-39 sheets that were attached to a thin film of natural uranium. Maintaining the chemical etching parameters constant and varying the exposition time, ɛ0 is observed to be constant for track densities varying between values approximately equal to the track background and those corresponding to the track overlapping limit, where track counting becomes difficult ( ˜10 5 cm-2 at our conditions). Otherwise, keeping constant the exposition time and varying the etching temperature, a variation in ɛ0 is found if a usual track counting criterion is employed. However, such a variation vanishes statistically when a more rigorous criterion is adopted.

  8. The software peculiarities of pattern recognition in track detectors

    SciTech Connect

    Starkov, N.

    2015-12-31

    The different kinds of nuclear track recognition algorithms are represented. Several complicated samples of use them in physical experiments are considered. The some processing methods of complicated images are described.

  9. Nuclear rights - nuclear wrongs

    SciTech Connect

    Paul, E.F.; Miller, F.D.; Paul, J.; Ahrens, J.

    1986-01-01

    This book contains 11 selections. The titles are: Three Ways to Kill Innocent Bystanders: Some Conundrums Concerning the Morality of War; The International Defense of Liberty; Two Concepts of Deterrence; Nuclear Deterrence and Arms Control; Ethical Issues for the 1980s; The Moral Status of Nuclear Deterrent Threats; Optimal Deterrence; Morality and Paradoxical Deterrence; Immoral Risks: A Deontological Critique of Nuclear Deterrence; No War Without Dictatorship, No Peace Without Democracy: Foreign Policy as Domestic Politics; Marxism-Leninism and its Strategic Implications for the United States; Tocqueveille War.

  10. Solar tracking system

    DOEpatents

    Okandan, Murat; Nielson, Gregory N.

    2016-07-12

    Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

  11. Straight-Pore Microfilter with Efficient Regeneration

    NASA Technical Reports Server (NTRS)

    Liu, Han; LaConti, Anthony B.; McCallum. Thomas J.; Schmitt, Edwin W.

    2010-01-01

    A novel, high-efficiency gas particulate filter has precise particle size screening, low pressure drop, and a simple and fast regeneration process. The regeneration process, which requires minimal material and energy consumption, can be completely automated, and the filtration performance can be restored within a very short period of time. This filter is of a novel material composite that contains the support structure and a novel coating.

  12. TrackEye tracking algorithm characterization

    NASA Astrophysics Data System (ADS)

    Valley, Michael T.; Shields, Robert W.; Reed, Jack M.

    2004-10-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  13. TrackEye tracking algorithm characterization.

    SciTech Connect

    Reed, Jack W.; Shields, Rob W; Valley, Michael T.

    2004-08-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  14. Nuclear forensics: Soil content

    SciTech Connect

    Beebe, Merilyn Amy

    2015-08-31

    Nuclear Forensics is a growing field that is concerned with all stages of the process of creating and detonating a nuclear weapon. The main goal is to prevent nuclear attack by locating and securing nuclear material before it can be used in an aggressive manner. This stage of the process is mostly paperwork; laws, regulations, treaties, and declarations made by individual countries or by the UN Security Council. There is some preliminary leg work done in the form of field testing detection equipment and tracking down orphan materials; however, none of these have yielded any spectacular or useful results. In the event of a nuclear attack, the first step is to analyze the post detonation debris to aid in the identification of the responsible party. This aspect of the nuclear forensics process, while reactive in nature, is more scientific. A rock sample taken from the detonation site can be dissolved into liquid form and analyzed to determine its chemical composition. The chemical analysis of spent nuclear material can provide valuable information if properly processed and analyzed. In order to accurately evaluate the results, scientists require information on the natural occurring elements in the detonation zone. From this information, scientists can determine what percentage of the element originated in the bomb itself rather than the environment. To this end, element concentrations in soils from sixty-nine different cities are given, along with activity concentrations for uranium, thorium, potassium, and radium in various building materials. These data are used in the analysis program Python.

  15. Can we track holes?

    PubMed Central

    Horowitz, Todd S.; Kuzmova, Yoana

    2011-01-01

    The evidence is mixed as to whether the visual system treats objects and holes differently. We used a multiple object tracking task to test the hypothesis that figural objects are easier to track than holes. Observers tracked four of eight items (holes or objects). We used an adaptive algorithm to estimate the speed allowing 75% tracking accuracy. In Experiments 1–5, the distinction between holes and figures was accomplished by pictorial cues, while red-cyan anaglyphs were used to provide the illusion of depth in Experiment 6. We variously used Gaussian pixel noise, photographic scenes, or synthetic textures as backgrounds. Tracking was more difficult when a complex background was visible, as opposed to a blank background. Tracking was easier when disks carried fixed, unique markings. When these factors were controlled for, tracking holes was no more difficult than tracking figures, suggesting that they are equivalent stimuli for tracking purposes. PMID:21334361

  16. Can we track holes?

    PubMed

    Horowitz, Todd S; Kuzmova, Yoana

    2011-05-11

    The evidence is mixed as to whether the visual system treats objects and holes differently. We used a multiple object tracking task to test the hypothesis that figural objects are easier to track than holes. Observers tracked four of eight items (holes or objects). We used an adaptive algorithm to estimate the speed allowing 75% tracking accuracy. In Experiments 1-5, the distinction between holes and figures was accomplished by pictorial cues, while red-cyan anaglyphs were used to provide the illusion of depth in Experiment 6. We variously used Gaussian pixel noise, photographic scenes, or synthetic textures as backgrounds. Tracking was more difficult when a complex background was visible, as opposed to a blank background. Tracking was easier when disks carried fixed, unique markings. When these factors were controlled for, tracking holes was no more difficult than tracking figures, suggesting that they are equivalent stimuli for tracking purposes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. TrackEtching - A Java based code for etched track profile calculations in SSNTDs

    NASA Astrophysics Data System (ADS)

    Muraleedhara Varier, K.; Sankar, V.; Gangadathan, M. P.

    2017-09-01

    A java code incorporating a user friendly GUI has been developed to calculate the parameters of chemically etched track profiles of ion-irradiated solid state nuclear track detectors. Huygen's construction of wavefronts based on secondary wavelets has been used to numerically calculate the etched track profile as a function of the etching time. Provision for normal incidence and oblique incidence on the detector surface has been incorporated. Results in typical cases are presented and compared with experimental data. Different expressions for the variation of track etch rate as a function of the ion energy have been utilized. The best set of values of the parameters in the expressions can be obtained by comparing with available experimental data. Critical angle for track development can also be calculated using the present code.

  18. Nuclear Medicine.

    ERIC Educational Resources Information Center

    Badawi, Ramsey D.

    2001-01-01

    Describes the use of nuclear medicine techniques in diagnosis and therapy. Describes instrumentation in diagnostic nuclear medicine and predicts future trends in nuclear medicine imaging technology. (Author/MM)

  19. Nuclear ventriculography

    MedlinePlus

    ... ventriculography (RNV); Multiple gate acquisition scan (MUGA); Nuclear cardiology; Cardiomyopathy - nuclear ventriculography ... 56. Udelson JE, Dilsizian V, Bonow RO. Nuclear cardiology. In: Bonow RO, Mann DL, Zipes DP, Libby ...

  20. Nuclear Medicine.

    ERIC Educational Resources Information Center

    Badawi, Ramsey D.

    2001-01-01

    Describes the use of nuclear medicine techniques in diagnosis and therapy. Describes instrumentation in diagnostic nuclear medicine and predicts future trends in nuclear medicine imaging technology. (Author/MM)

  1. Nuclear data for nuclear transmutation

    SciTech Connect

    Harada, Hideo

    2009-05-04

    Current status on nuclear data for the study of nuclear transmutation of radioactive wastes is reviewed, mainly focusing on neutron capture reactions. It is stressed that the highest-precision frontier research in nuclear data measurements should be a key to satisfy the target accuracies on the nuclear data requested for realizing the nuclear transmutation.

  2. Nuclear data for nuclear transmutation

    NASA Astrophysics Data System (ADS)

    Harada, Hideo

    2009-05-01

    Current status on nuclear data for the study of nuclear transmutation of radioactive wastes is reviewed, mainly focusing on neutron capture reactions. It is stressed that the highest-precision frontier research in nuclear data measurements should be a key to satisfy the target accuracies on the nuclear data requested for realizing the nuclear transmutation.

  3. Tracking Earthquake Cascades

    NASA Astrophysics Data System (ADS)

    Jordan, T. H.

    2011-12-01

    In assessing their risk to society, earthquakes are best characterized as cascades that can propagate from the natural environment into the socio-economic (built) environment. Strong earthquakes rarely occur as isolated events; they usually cluster in foreshock-mainshock-aftershock sequences, seismic swarms, and extended sequences of large earthquakes that propagate along major fault systems. These cascades are regulated by stress-mediated interactions among faults driven by tectonic loading. Within these cascades, each large event can itself cause a chain reaction in which the primary effects of faulting and ground shaking induce secondary effects, including tsunami, landslides, liquefaction, and set off destructive processes within the built environment, such as fires and radiation leakage from nuclear plants. Recent earthquakes have demonstrated how the socio-economic effects of large earthquakes can reverberate for many years. To reduce earthquake risk and improve the resiliency of communities to earthquake damage, society depends on five geotechnologies for tracking earthquake cascades: long-term probabilistic seismic hazard analysis (PSHA), short-term (operational) earthquake forecasting, earthquake early warning, tsunami warning, and the rapid production of post-event information for response and recovery (see figure). In this presentation, I describe how recent advances in earthquake system science are leading to improvements in this geotechnology pipeline. In particular, I will highlight the role of earthquake simulations in predicting strong ground motions and their secondary effects before and during earthquake cascades

  4. Atomistic simulation of track formation by energetic recoils in zircon.

    PubMed

    Moreira, Pedro A F P; Devanathan, Ram; Weber, William J

    2010-10-06

    We have performed classical molecular dynamics simulations of fission track formation in zircon. We simulated the passage of a swift heavy ion through crystalline zircon using cylindrical thermal spikes with energy deposition (dE/dx) of 2.5-12.8 keV nm( - 1) and a radius of 3 nm. At a low dE/dx of 2.55 keV nm( - 1), the structural damage recovered almost completely and a damage track was not produced. At higher values of dE/dx, tracks were observed and the radius of the track increased with increasing dE/dx. Our structural analysis shows amorphization in the core of the track and phase separation into Si-rich regions near the center of the track and Zr-rich regions near the periphery. These simulations establish a threshold dE/dx for fission track formation in zircon that is relevant to thermochronology and nuclear waste immobilization.

  5. Calculating track thrust with track functions

    NASA Astrophysics Data System (ADS)

    Chang, Hsi-Ming; Procura, Massimiliano; Thaler, Jesse; Waalewijn, Wouter J.

    2013-08-01

    In e+e- event shapes studies at LEP, two different measurements were sometimes performed: a “calorimetric” measurement using both charged and neutral particles and a “track-based” measurement using just charged particles. Whereas calorimetric measurements are infrared and collinear safe, and therefore calculable in perturbative QCD, track-based measurements necessarily depend on nonperturbative hadronization effects. On the other hand, track-based measurements typically have smaller experimental uncertainties. In this paper, we present the first calculation of the event shape “track thrust” and compare to measurements performed at ALEPH and DELPHI. This calculation is made possible through the recently developed formalism of track functions, which are nonperturbative objects describing how energetic partons fragment into charged hadrons. By incorporating track functions into soft-collinear effective theory, we calculate the distribution for track thrust with next-to-leading logarithmic resummation. Due to a partial cancellation between nonperturbative parameters, the distributions for calorimeter thrust and track thrust are remarkably similar, a feature also seen in LEP data.

  6. To Track or Not to Track?

    ERIC Educational Resources Information Center

    Hesson, Heather

    2010-01-01

    Background: This paper was written for a graduate level action research course at Muskingum University, located in New Concord, OH. Purpose: The purpose of this research was to determine which method of instruction best serves ALL high school students. Is it more advantageous to track ("ability group") students or not to track students…

  7. Multiple frame cluster tracking

    NASA Astrophysics Data System (ADS)

    Gadaleta, Sabino; Klusman, Mike; Poore, Aubrey; Slocumb, Benjamin J.

    2002-08-01

    Tracking large number of closely spaced objects is a challenging problem for any tracking system. In missile defense systems, countermeasures in the form of debris, chaff, spent fuel, and balloons can overwhelm tracking systems that track only individual objects. Thus, tracking these groups or clusters of objects followed by transitions to individual object tracking (if and when individual objects separate from the groups) is a necessary capability for a robust and real-time tracking system. The objectives of this paper are to describe the group tracking problem in the context of multiple frame target tracking and to formulate a general assignment problem for the multiple frame cluster/group tracking problem. The proposed approach forms multiple clustering hypotheses on each frame of data and base individual frame clustering decisions on the information from multiple frames of data in much the same way that MFA or MHT work for individual object tracking. The formulation of the assignment problem for resolved object tracking and candidate clustering methods for use in multiple frame cluster tracking are briefly reviewed. Then, three different formulations are presented for the combination of multiple clustering hypotheses on each frame of data and the multiple frame assignments of clusters between frames.

  8. Renewable Energy Tracking Systems

    EPA Pesticide Factsheets

    Renewable energy generation ownership can be accounted through tracking systems. Tracking systems are highly automated, contain specific information about each MWh, and are accessible over the internet to market participants.

  9. Comparison of SEM and Optical Analysis of DT Neutron Tracks in CR-39 Detectors

    SciTech Connect

    P.A. Mosier-Boss, L.P.G. Forsley, P. Carbonnelle, M.S. Morey, J.R. Tinsley, J. P. Hurley, F.E. Gordon

    2012-01-01

    A solid state nuclear track detector, CR-39, was exposed to DT neutrons. After etching, the resultant tracks were analyzed using both an optical microscope and a scanning electron microscope (SEM). In this communication, both methods of analyzing DT neutron tracks are discussed.

  10. Solar tracking apparatus

    DOEpatents

    Hammons, B.E.

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxilliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  11. Solar tracking apparatus

    DOEpatents

    Hammons, Burrell E.

    1980-01-01

    The invention relates to a solar tracking device which tracks the position of the sun using paired, partially-shaded photocells. Auxiliary photocells are used for initial acquisition of the sun and for the suppression of false tracking when the sun is obscured by clouds.

  12. Track Dynamics Program

    DTIC Science & Technology

    1978-10-01

    better underptanding of track dynamics and performance. Analytical techniques were developed to predict track vibration mode3, chordal action effects ...buildup, and end connector tightening I] effectiveness . Double-pin track for heavy tanks was analyzed with these techniques, and designs for improved...o. Pin and Bushing Loads and Deflections . . . a 0 . . 6 Effects of Obstacle Negotiation . . . . . . . . . . 7 Thermal Analysis

  13. Track finding efficiency in

    SciTech Connect

    Allmendinger, T.; Bhuyan, B.; Brown, D. N.; Choi, H.; Christ, S.; Covarelli, R.; Davier, M.; Denig, A. G.; Fritsch, M.; Hafner, A.; Kowalewski, R.; Long, O.; Lutz, A. M.; Martinelli, M.; Muller, D. R.; Nugent, I. M.; Lopes Pegna, D.; Purohit, M. V.; Prencipe, E.; Roney, J. M.; Simi, G.; Solodov, E. P.; Telnov, A. V.; Varnes, E.; Waldi, R.; Wang, W. F.; White, R. M.

    2012-12-10

    We describe several studies to measure the charged track reconstruction efficiency and asymmetry of the BaBar detector. The first two studies measure the tracking efficiency of a charged particle using τ and initial state radiation decays. The third uses the τ decays to study the asymmetry in tracking, the fourth measures the tracking efficiency for low momentum tracks, and the last measures the reconstruction efficiency of K$0\\atop{S}$ particles. The first section also examines the stability of the measurements vs. BaBar running periods.

  14. Object tracking with stereo vision

    NASA Technical Reports Server (NTRS)

    Huber, Eric

    1994-01-01

    A real-time active stereo vision system incorporating gaze control and task directed vision is described. Emphasis is placed on object tracking and object size and shape determination. Techniques include motion-centroid tracking, depth tracking, and contour tracking.

  15. Birth Defects Research and Tracking

    MedlinePlus

    ... this? Submit Button Information For… Media Policy Makers Research and Tracking Recommend on Facebook Tweet Share Compartir ... to help prevent them. Importance of Tracking and Research Tracking: Birth defects tracking systems identify babies born ...

  16. Tracking dynamic team activity

    SciTech Connect

    Tambe, M.

    1996-12-31

    AI researchers are striving to build complex multi-agent worlds with intended applications ranging from the RoboCup robotic soccer tournaments, to interactive virtual theatre, to large-scale real-world battlefield simulations. Agent tracking - monitoring other agent`s actions and inferring their higher-level goals and intentions - is a central requirement in such worlds. While previous work has mostly focused on tracking individual agents, this paper goes beyond by focusing on agent teams. Team tracking poses the challenge of tracking a team`s joint goals and plans. Dynamic, real-time environments add to the challenge, as ambiguities have to be resolved in real-time. The central hypothesis underlying the present work is that an explicit team-oriented perspective enables effective team tracking. This hypothesis is instantiated using the model tracing technology employed in tracking individual agents. Thus, to track team activities, team models are put to service. Team models are a concrete application of the joint intentions framework and enable an agent to track team activities, regardless of the agent`s being a collaborative participant or a non-participant in the team. To facilitate real-time ambiguity resolution with team models: (i) aspects of tracking are cast as constraint satisfaction problems to exploit constraint propagation techniques; and (ii) a cost minimality criterion is applied to constrain tracking search. Empirical results from two separate tasks in real-world, dynamic environments one collaborative and one competitive - are provided.

  17. A 3D feature point tracking method for ion radiation

    NASA Astrophysics Data System (ADS)

    Kouwenberg, Jasper J. M.; Ulrich, Leonie; Jäkel, Oliver; Greilich, Steffen

    2016-06-01

    A robust and computationally efficient algorithm for automated tracking of high densities of particles travelling in (semi-) straight lines is presented. It extends the implementation of (Sbalzarini and Koumoutsakos 2005) and is intended for use in the analysis of single ion track detectors. By including information of existing tracks in the exclusion criteria and a recursive cost minimization function, the algorithm is robust to variations on the measured particle tracks. A trajectory relinking algorithm was included to resolve the crossing of tracks in high particle density images. Validation of the algorithm was performed using fluorescent nuclear track detectors (FNTD) irradiated with high- and low (heavy) ion fluences and showed less than 1% faulty trajectories in the latter.

  18. The Tracking System in the Panda Apparatus

    NASA Astrophysics Data System (ADS)

    Wintz, P.

    2012-08-01

    The bar {P}ANDA experiment at the new FAIR facility at Darmstadt (Germany) will investigate antiproton collisions on proton and nuclear targets in the charm quark mass regime. The wide-range physics program requires a universal detector concept, combining state-of-the-art and novel techniques in particle measurements and data readout. This paper gives an overview of the detector setup and summarizes the status, in particular of the charged particle tracking detectors in the bar {P}ANDA spectrometer.

  19. Nuclear Chemistry.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  20. Nuclear Scans

    MedlinePlus

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  1. Nuclear Winter.

    ERIC Educational Resources Information Center

    Ehrlich, Anne

    1984-01-01

    "Nuclear Winter" was recently coined to describe the climatic and biological effects of a nuclear war. These effects are discussed based on models, simulations, scenarios, and projections. Effects on human populations are also considered. (JN)

  2. Nuclear Medicine

    MedlinePlus

    ... Home » Science Education » Science Topics » Nuclear Medicine SCIENCE EDUCATION SCIENCE EDUCATION Science Topics Resource Links for General Public Resource ... Related Documents: Nuclear Medicine Fact Sheet.pdf SCIENCE EDUCATION Science Topics Resource Links for General Public Resource ...

  3. Nuclear Chemistry.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1979

    1979-01-01

    Provides a brief review of the latest developments in nuclear chemistry. Nuclear research today is directed toward increased activity in radiopharmaceuticals and formation of new isotopes by high-energy, heavy-ion collisions. (Author/BB)

  4. Nuclear Winter.

    ERIC Educational Resources Information Center

    Ehrlich, Anne

    1984-01-01

    "Nuclear Winter" was recently coined to describe the climatic and biological effects of a nuclear war. These effects are discussed based on models, simulations, scenarios, and projections. Effects on human populations are also considered. (JN)

  5. Tracking in anatomic pathology.

    PubMed

    Pantanowitz, Liron; Mackinnon, Alexander C; Sinard, John H

    2013-12-01

    Bar code-based tracking solutions, long present in clinical pathology laboratories, have recently made an appearance in anatomic pathology (AP) laboratories. Tracking of AP "assets" (specimens, blocks, slides) can enhance laboratory efficiency, promote patient safety, and improve patient care. Routing of excess clinical material into research laboratories and biorepositories are other avenues that can benefit from tracking of AP assets. Implementing tracking is not as simple as installing software and turning it on. Not all tracking solutions are alike. Careful analysis of laboratory workflow is needed before implementing tracking to assure that this solution will meet the needs of the laboratory. Such analysis will likely uncover practices that may need to be modified before a tracking system can be deployed. Costs that go beyond simply that of purchasing software will be incurred and need to be considered in the budgeting process. Finally, people, not technology, are the key to assuring quality. Tracking will require significant changes in workflow and an overall change in the culture of the laboratory. Preparation, training, buy-in, and accountability of the people involved are crucial to the success of this process. This article reviews the benefits, available technology, underlying principles, and implementation of tracking solutions for the AP and research laboratory.

  6. Tracking Small Artists

    NASA Astrophysics Data System (ADS)

    Russell, James C.; Klette, Reinhard; Chen, Chia-Yen

    Tracks of small animals are important in environmental surveillance, where pattern recognition algorithms allow species identification of the individuals creating tracks. These individuals can also be seen as artists, presented in their natural environments with a canvas upon which they can make prints. We present tracks of small mammals and reptiles which have been collected for identification purposes, and re-interpret them from an esthetic point of view. We re-classify these tracks not by their geometric qualities as pattern recognition algorithms would, but through interpreting the 'artist', their brush strokes and intensity. We describe the algorithms used to enhance and present the work of the 'artists'.

  7. Nuclear weapons, nuclear effects, nuclear war

    SciTech Connect

    Bing, G.F.

    1991-08-20

    This paper provides a brief and mostly non-technical description of the militarily important features of nuclear weapons, of the physical phenomena associated with individual explosions, and of the expected or possible results of the use of many weapons in a nuclear war. Most emphasis is on the effects of so-called ``strategic exchanges.``

  8. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  9. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  10. Nuclear Pasta

    NASA Astrophysics Data System (ADS)

    da Silva Schneider, Andre; Horowitz, Charles; Berry, Don; Briggs, Christian

    2014-03-01

    For decades it has been theorized that just below nuclear saturation density matter undergoes a series of phase transitions. These phases, which are expected to exist in core-collapse supernovae and neutron stars, involve a range of exotic nuclear shapes collectively known as nuclear pasta. Recently, Jose Pons and collaborators suggested that ``the maximum period of isolated X-ray pulsars may be the first observational evidence for an amorphous inner crust, ..., possibly owing to the existence of a nuclear pasta phase.'' In this talk we present results of semi-classical molecular dynamics simulations of nuclear pasta and discuss how each phase might contribute to neutron star crust properties.

  11. Nuclear orientation and nuclear structure

    SciTech Connect

    Krane, K.S.

    1988-01-01

    The present generation of on-line nuclear orientation facilities promises to revolutionize the gathering of nuclear structure information, especially for the hitherto poorly known and understood nuclei far from stability. Following a brief review of the technological developments that have facilitated these experiments, the nuclear spectroscopic information that can be obtained is summarized. Applications to understanding nuclear structure are reviewed, and challenges for future studies are discussed. 14 refs., 4 figs., 3 tabs.

  12. Nuclear networking.

    PubMed

    Xie, Wei; Burke, Brian

    2017-07-04

    Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

  13. UWB Tracking Software Development

    NASA Technical Reports Server (NTRS)

    Gross, Julia; Arndt, Dickey; Ngo, Phong; Phan, Chau; Dusl, John; Ni, Jianjun; Rafford, Melinda

    2006-01-01

    An Ultra-Wideband (UWB) two-cluster Angle of Arrival (AOA) tracking prototype system is currently being developed and tested at NASA Johnson Space Center for space exploration applications. This talk discusses the software development efforts for this UWB two-cluster AOA tracking system. The role the software plays in this system is to take waveform data from two UWB radio receivers as an input, feed this input into an AOA tracking algorithm, and generate the target position as an output. The architecture of the software (Input/Output Interface and Algorithm Core) will be introduced in this talk. The development of this software has three phases. In Phase I, the software is mostly Matlab driven and calls C++ socket functions to provide the communication links to the radios. This is beneficial in the early stage when it is necessary to frequently test changes in the algorithm. Phase II of the development is to have the software mostly C++ driven and call a Matlab function for the AOA tracking algorithm. This is beneficial in order to send the tracking results to other systems and also to improve the tracking update rate of the system. The third phase is part of future work and is to have the software completely C++ driven with a graphics user interface. This software design enables the fine resolution tracking of the UWB two-cluster AOA tracking system.

  14. Large scale tracking algorithms

    SciTech Connect

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  15. Track Starter's Guide.

    ERIC Educational Resources Information Center

    Dailey, Charles H.; Rankin, Kelly D.

    This guide was developed to serve both the novice and experienced starter in track and field events. Each year in the United States, runners encounter dozens of different starters' mannerisms as they travel to track meets in various towns and states. The goal of any competent and conscientious starter is to insure that all runners receive a fair…

  16. 2 Tracks for Faculty

    ERIC Educational Resources Information Center

    Wilson, Robin

    2012-01-01

    The academic work force has been transformed over the past several decades, less by design than out of expediency. In 1969, professors who were either tenured or tenure-track made up 78 percent of the faculty. Those working part time made up only 18.5 percent. By 2009, those proportions had almost flipped, with tenured and tenure-track making up…

  17. Incentives from Curriculum Tracking

    ERIC Educational Resources Information Center

    Koerselman, Kristian

    2013-01-01

    Curriculum tracking creates incentives in the years before its start, and we should therefore expect test scores to be higher during those years. I find robust evidence for incentive effects of tracking in the UK based on the UK comprehensive school reform. Results from the Swedish comprehensive school reform are inconclusive. Internationally, I…

  18. 2 Tracks for Faculty

    ERIC Educational Resources Information Center

    Wilson, Robin

    2012-01-01

    The academic work force has been transformed over the past several decades, less by design than out of expediency. In 1969, professors who were either tenured or tenure-track made up 78 percent of the faculty. Those working part time made up only 18.5 percent. By 2009, those proportions had almost flipped, with tenured and tenure-track making up…

  19. Photon track evolution.

    PubMed

    Oliveira, A D

    2005-01-01

    Given the time scale of biological, biochemical, biophysical and physical effects in a radiation exposure of living tissue, the first physical stage can be considered to be independent of time. All the physical interactions caused by the incident photons happen at the same starting time. From this point of view it would seem that the evolution of photon tracks is not a relevant topic for analysis; however, if the photon track is considered as a sequence of several interactions, there are several steps until the total degradation of the energy of the primary photon. We can characterise the photon track structure by the probability p(E,j), that is, the probability that a photon with energy E suffers j secondary interactions. The aim of this work is to analyse the photon track structure by considering j as a step of the photon track evolution towards the total degradation of the photon energy. Low energy photons (<150 keV) are considered, with water phantoms and half-extended geometry. The photon track evolution concept is presented and compared with the energy deposition along the track and also with the spatial distribution of the several steps in the photon track.

  20. Can Tracking Improve Learning?

    ERIC Educational Resources Information Center

    Duflo, Esther; Dupas, Pascaline; Kremer, Michael

    2009-01-01

    Tracking students into different classrooms according to their prior academic performance is controversial among both scholars and policymakers. If teachers find it easier to teach a homogeneous group of students, tracking could enhance school effectiveness and raise test scores of both low- and high-ability students. If students benefit from…

  1. Incentives from Curriculum Tracking

    ERIC Educational Resources Information Center

    Koerselman, Kristian

    2013-01-01

    Curriculum tracking creates incentives in the years before its start, and we should therefore expect test scores to be higher during those years. I find robust evidence for incentive effects of tracking in the UK based on the UK comprehensive school reform. Results from the Swedish comprehensive school reform are inconclusive. Internationally, I…

  2. TRACKED VEHICLE Rev 75

    SciTech Connect

    Raby, Eric Y.

    2007-05-08

    Revision 75 of the Tracked Vehicle software is a soft real-time simulation of a differentially steered, tracked mobile robot, which, because of the track flippers, resembles the iRobot PackBot (http://www.irobot.com/). Open source libraries are used for the physics engine (http://www.ode.org/), the display and user interface (http://www.mathies.com/cpw/), and the program command line and configuration file parameters (http://www.boost.org/). The simulation can be controlled by a USB joystick or the keyboard. The configuration file contains demonstration model parameters of no particular vehicle. This simulation can be used as a starting point for those doing tracked vehicle simulations. This simulation software is essentially a research tool which can be modified and adapted for certain types of tracked vehicle research. An open source license allows an individual researchers to tailor the code to their specific research needs.

  3. Nested Tracking Graphs

    DOE PAGES

    Lukasczyk, Jonas; Weber, Gunther; Maciejewski, Ross; ...

    2017-06-01

    Tracking graphs are a well established tool in topological analysis to visualize the evolution of components and their properties over time, i.e., when components appear, disappear, merge, and split. However, tracking graphs are limited to a single level threshold and the graphs may vary substantially even under small changes to the threshold. To examine the evolution of features for varying levels, users have to compare multiple tracking graphs without a direct visual link between them. We propose a novel, interactive, nested graph visualization based on the fact that the tracked superlevel set components for different levels are related to eachmore » other through their nesting hierarchy. This approach allows us to set multiple tracking graphs in context to each other and enables users to effectively follow the evolution of components for different levels simultaneously. We show the effectiveness of our approach on datasets from finite pointset methods, computational fluid dynamics, and cosmology simulations.« less

  4. Employing wavelet for neutron tracks distribution analysis in PADC detectors

    NASA Astrophysics Data System (ADS)

    Ferrari, Paolo; Campani, Lorenzo; Mariotti, Francesca

    2017-08-01

    PADC nuclear track dosemeters are used for fast neutron monitoring. A system, based on one-shot image acquisition is employed and a simple image analysis, based on the track counting, is performed in a series of image regions. When this procedure fails a different approach is needed. In the present paper we tested a wavelet transform based algorithm to detect possible ;patterns; in tracks distributions that could be associated to dosemeter anomalies, assuming that a neutron exposure should produce a homogenous distribution. The algorithm, tested with samples of our dosimetric service, showed its potential effectiveness and capabilities.

  5. Nuclear Halos

    SciTech Connect

    Vogt, Erich

    2010-07-27

    We show that extreme nuclear halos are caused only by pairs of s-wave neutrons (or single s-wave neutrons) and that such states occur much more frequently in the periodic table than previously believed. Besides lingering long near zero neutron separation energy such extreme halos have very remarkable properties: they can contribute significantly to the nuclear density at more than twice the normal nuclear radius and their spreading width can be very narrow. The properties of these states are primarily determined by the ''thickness'' of the nuclear surface in the mean-free nuclear potential and thus their importance increases greatly as we approach the neutron drip line. We discuss what such extreme halos are, where they occur, what their properties are and some of their impact on nuclear observations.

  6. Individual and grouping track pits etched in the exposed in a free space plastic track detectors

    NASA Astrophysics Data System (ADS)

    Kashkarov, L.; Bazhutov, Yu

    2013-02-01

    New results concerned to the investigation of depth-dependent the pit-like surface-average and the grouping track-density distributions in the cosmic ray exposed column of CN-85 and CR-39 plastic solid state nuclear track detectors (SSNTD) are presented. Two main sources: solar cosmic ray protons and recoil nuclei for very short (length <3 μm) track-pit formation are considered. Theoretical estimation of the total, uniform track-pit density indicates on failure of evidence of some additional radiation effects, partially, hypothetically conditioned with the Erzion theory. Some quantitative proofs of this hypothesis have been obtained in the measurements of the pit-groups. Totally, up to this time it was registered near of 30 pit groups with the surface pit-density in the interval of (1-15) × 106 cm2, that is two-three orders of magnitude higher than uniformly distributed track-pits on the same CR-39 plate surface. As a result of layer-by-layer investigation of the exposed CN-85 stock arrangement three pit swarms exactly correlated with the end point of high ionizing primary charge particle tracks were observed. Obtained data are considered in according to submission based on the probability of detection for the negative charged cosmic ray Erzion particles stopping events.

  7. Nuclear astrophysics

    SciTech Connect

    Haxton, W.C.

    1992-01-01

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

  8. Nuclear astrophysics

    SciTech Connect

    Haxton, W.C.

    1992-12-31

    The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

  9. Methods for the assessment of long-lived radionuclides in humans resulting from nuclear activities or accidents: Fission track analysis of trace amounts plutonium-239 and a copper hexacyanoferrate kit for monitoring radiocaesium

    NASA Astrophysics Data System (ADS)

    Johansson, Lena Camilla

    Fission track analysis (FTA) was developed to be applied to ultra-low levels of 239Pu in bioassay samples. An analytical protocol was established for the FTA processing. The detection limit was determined to 1.5 μBq and the calibration constant was 24 fission fragments per μBq 239Pu. Naturally occurring nuclides of thorium and uranium, present in biological and environmental samples, did not interfere in the determination of 239Pu. Self-absorption of fission fragments was shown to be insignificant. The study included the determination of 239Pu in urine samples from twenty Chernobyl clean-up workers. All urine samples contained activities below the detection limit for radioanalytical analysis using alpha spectrometry (0.5 mBq). Seven of the samples were further investigated using a thermal ionization mass spectrometer with a sensitivity of 106 atoms 239Pu. The content of 239Pu in the samples showed to be below 1μBq (106 atoms), with only one exception. It was not possible to draw any major conclusions from the 239Pu results, regarding the clean-up workers' exposure from radionuclides released by the Chernobyl accident. A kit was designed for selective adsorption of radiocaesium in urine samples to be used in situ by contaminated subjects. The kit consisted of copper hexacyanoferrate impregnated cotton filters held by filter holders for sample flow-through. After use, the adsorbed fraction of caesium was >=90% in urine samples. The kit facilitates the screening of a population exposed to radiocaesium. Parameters influencing the adsorption efficiency, such as potassium, sodium and calcium concentration of the sample and the sample pH, were investigated and shown to be insignificant for urine samples.

  10. Nuclear Fission

    NASA Astrophysics Data System (ADS)

    Denschlag, J. O.

    This chapter first gives a survey on the history of the discovery of nuclear fission. It briefly presents the liquid-drop and shell models and their application to the fission process. The most important quantities accessible to experimental determination such as mass yields, nuclear charge distribution, prompt neutron emission, kinetic energy distribution, ternary fragment yields, angular distributions, and properties of fission isomers are presented as well as the instrumentation and techniques used for their measurement. The contribution concentrates on the fundamental aspects of nuclear fission. The practical aspects of nuclear fission are discussed in http://dx.doi.org/10.1007/978-1-4419-0720-2_57 of Vol. 6.

  11. Nuclear Safety

    SciTech Connect

    Silver, E G

    1989-01-01

    This document is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated.

  12. Tracks of a Giant

    NASA Image and Video Library

    2010-08-25

    The giant, 70-meter-wide antenna at NASA Deep Space Network complex in Goldstone, Calif., tracks a spacecraft on Nov. 17, 2009. This antenna, officially known as Deep Space Station 14, is also nicknamed the Mars antenna.

  13. Maximum power tracking

    SciTech Connect

    O'Sullivan, G.

    1983-03-01

    By definition, a maximum power tracking device causes the photovoltaic array to operate on the locus of maximum power points within a specified accuracy. There are limitations to the application of maximum power tracking. A prerequisite is that the load be capable of absorbing all of the power availble at all times. Battery chargers, electrical heaters, water pumps, and most significantly, returning power to the utility grid, are prime examples of applications that are adaptable to maximum power tracking. Maximum power tracking is available to either dc or ac loads. An inverter equipped with a means of changing input voltage by controlling its input impedance can deliver maximum power to ac loads. The inverter can be fixed or variable frequency and fixed or variable voltage, but must be compatible with the ac load. The discussion includes applications, techniques, and cost factors.

  14. Ion track doping

    NASA Astrophysics Data System (ADS)

    Fink, D.; Chadderton, L. T.; Cruz, S. A.; Fahrner, W. R.; Hnatowicz, V.; Te Kaat, E. H.; Melnikov, A. A.; Varichenko, V. S.; Zaitsev, A. M.

    1994-10-01

    Longitudinal dopant distribution along ion tracks in soft (polymers [1?5]) and hard (diamond [6,7]) condensed carbonaceous matter have been studied by neutron depth profiling and cathodoluminesence. Both in-diffusion from the aqueous phase and energetic ion implantation were used in primary track doping. In-situ self-decoration of tracks and post-implantation with a secondary ion species were used in the specific case of ion implantation. Radial dopant distributions were also studied by means of a modified tomographic procedure. Decorative doping of ion bombarded solids is useful in probing track structure, and especially in pointing the way to potential development of nanometric-sized electronic devices.

  15. Reading the Rover Tracks

    NASA Image and Video Library

    2012-08-29

    The straight lines in Curiosity zigzag track marks are Morse code for JPL. The footprint is an important reference mark that the rover can use to drive more precisely via a system called visual odometry.

  16. Tracks in, Path out?

    NASA Image and Video Library

    2009-12-01

    This view from the navigation camera near the top of the mast on NASA Mars Exploration Rover Spirit shows the tracks left by the rover as it drove southward and backward, dragging its inoperable right-front wheel.

  17. Energy Tracking Software Platform

    SciTech Connect

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  18. Analysis of latent tracks for MeV protons in CR-39

    NASA Astrophysics Data System (ADS)

    Kar, S.; Borghesi, M.; Romagnani, L.; Takahashi, S.; Zayats, A.; Malka, V.; Fritzler, S.; Schiavi, A.

    2007-02-01

    For protons of energy up to a few MeV, the temporal evolution of etched latent tracks in CR-39 nuclear track detector has been numerically modeled by assuming that the electronic energy loss of the protons governs the latent track formation. The technique is applied in order to obtain the energy spectrum of high intensity laser driven proton beams, with high accuracy. The precise measurement of the track length and areal track density have been achieved by scanning short etched, highly populated CR-39 employing atomic force microscope.

  19. Vehicle Tracking and Security

    NASA Astrophysics Data System (ADS)

    Scorer, A. G.

    1998-09-01

    This paper covers the wide area and short range locational technologies that are available for vehicle tracking in particular and mobile user security in general. It also summarises the radio communications services that can deliver information to the user. It considers the use that can be made of these technologies, when combined with procedures for delivering a response, in the security field, notably in relation to personal security, high-value load protection and the after-theft tracking markets.

  20. Advanced Doppler tracking experiments

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.

    1989-01-01

    The Doppler tracking method is currently the only technique available for broadband gravitational wave searches in the approx. 10(exp -4) to 10(exp -1) Hz low frequency band. A brief review is given of the Doppler method, a discussion of the main noise sources, and a review of experience with current spacecraft and the prospects for sensitivity improvements in an advanced Doppler tracking experiment.

  1. Nuclear safety

    NASA Technical Reports Server (NTRS)

    Buden, D.

    1991-01-01

    Topics dealing with nuclear safety are addressed which include the following: general safety requirements; safety design requirements; terrestrial safety; SP-100 Flight System key safety requirements; potential mission accidents and hazards; key safety features; ground operations; launch operations; flight operations; disposal; safety concerns; licensing; the nuclear engine for rocket vehicle application (NERVA) design philosophy; the NERVA flight safety program; and the NERVA safety plan.

  2. 3D imaging of neutron tracks using confocal microscopy

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin; Wertheim, David; Flowers, Alan

    2016-04-01

    Neutron detection and neutron flux assessment are important aspects in monitoring nuclear energy production. Neutron flux measurements can also provide information on potential biological damage from exposure. In addition to the applications for neutron measurement in nuclear energy, neutron detection has been proposed as a method of enhancing neutrino detectors and cosmic ray flux has also been assessed using ground-level neutron detectors. Solid State Nuclear Track Detectors (or SSNTDs) have been used extensively to examine cosmic rays, long-lived radioactive elements, radon concentrations in buildings and the age of geological samples. Passive SSNTDs consisting of a CR-39 plastic are commonly used to measure radon because they respond to incident charged particles such as alpha particles from radon gas in air. They have a large dynamic range and a linear flux response. We have previously applied confocal microscopy to obtain 3D images of alpha particle tracks in SSNTDs from radon track monitoring (1). As a charged particle traverses through the polymer it creates an ionisation trail along its path. The trail or track is normally enhanced by chemical etching to better expose radiation damage, as the damaged area is more sensitive to the etchant than the bulk material. Particle tracks in CR-39 are usually assessed using 2D optical microscopy. In this study 6 detectors were examined using an Olympus OLS4100 LEXT 3D laser scanning confocal microscope (Olympus Corporation, Japan). The detectors had been etched for 2 hours 50 minutes at 85 °C in 6.25M NaOH. Post etch the plastics had been treated with a 10 minute immersion in a 2% acetic acid stop bath, followed by rinsing in deionised water. The detectors examined had been irradiated with a 2mSv neutron dose from an Am(Be) neutron source (producing roughly 20 tracks per mm2). We were able to successfully acquire 3D images of neutron tracks in the detectors studied. The range of track diameter observed was between 4

  3. Nuclear privatization

    SciTech Connect

    Jeffs, E.

    1995-11-01

    The United Kingdom government announced in May 1995 plans to privatize the country`s two nuclear generating companies, Nuclear Electric and Scottish Nuclear. Under the plan, the two companies will become operating divisions of a unified holding company, to be called British Electric, with headquarters in Scotland. Britain`s nuclear plants were left out of the initial privatization in 1989 because the government believed the financial community would be unwilling to accept the open-ended liability of decommissioning the original nine stations based on the Magnox gas-cooled reactor. Six years later, the government has found a way around this by retaining these power stations in state ownership, leaving the new nuclear company with the eight Advanced Gas-cooled Reactor (AGR) stations and the recently completed Sizewell B PWR stations. The operating Magnox stations are to be transferred to BNFL, which operates two Magnox stations of their own at Calder Hall and Chapelcross.

  4. Nuclear materials

    SciTech Connect

    Not Available

    1992-08-01

    The Department of Energy (DOE) processes plutonium for use in nuclear weapons. This fact sheet responds to your September 6, 1991, request, that we describe the methods and facilities for DOE's plutonium processing. Plutonium, which is used to make nuclear weapons, does not exist in nature and has to be produced. However, DOE no longer produces plutonium for use in nuclear weapons. Instead, DOE processes and recycles the plutonium from retired nuclear weapons and the plutonium that remains as scrap or residue from plutonium processing. This paper reports that DOE recovers plutonium through two basic processes-aqueous and pyrochemical-at four processing sites-Rocky Flats, Savannah River, Hanford, and Los Alamos. However, because of environmental and safety concerns and reductions in nuclear weapons, DOE has closed or may close most of the processing facilities. Only Los Alamos' processing facilities are currently operating.

  5. Reviews Equipment: Time Trial R/C Race Track Timer Book: A Universe from Nothing Equipment: Locktronics Electronics, Magnestism and Materials Unit Report: Nuclear Physics and Technology Book: Particle Physics Booklet: Radiation and You Book: The Million Death Quake Web Watch

    NASA Astrophysics Data System (ADS)

    2013-03-01

    WE RECOMMEND Locktronics Electronics, Magnestism and Materials Unit Robust, reliable and proven classroom kit The Million Death Quake: the Science of Predicting the Earth's Deadliest Natural Disaster Accessible and well-written book covers everything you might (and perhaps should) want to know about earthquakes WORTH A LOOK Time Trial R/C Race Track Timer Fun kit for use with toy cars but little flexibility for other uses A Universe From Nothing: Why There is Something Rather Than Nothing Up-to-date account of cosmology explains very well but becomes polemical and loses focus Nuclear physics and technology—inside the atom IOP report useful for students considering a career in physics Particle Physics: A Very Short Introduction Passages of good writing undermined by editing as the structure and illustrations disappoint Radiation and You Report is an interesting insight into radiation information from 25 years back, but some errors and a slow start let it down WEB WATCH App that aids star identification is highly recommended and videos for students and teachers also make the grade

  6. Stimulus-responsive track pores

    NASA Astrophysics Data System (ADS)

    Yoshida, Masaru; Tamada, Masao; Asano, Masaharu; Omichi, Hideki; Kubota, Hitoshi; Katakai, Ryoichi; Spohr, Reimar; Vetter, Johann

    1993-03-01

    Ion track grafting enables the manufacture of chemically responsive track pores analogous to the discrete membrane channels found in biology. For this purpose etched ion tracks generated in CR-39 are surface-grafted by methacryloyl-L-alaninemethylester. In the future, the responsive track pores could be used to model the actively controlled channels in biomembranes and may lead to interesting technological applications.

  7. OCULUS Sea Track Fusion Service

    NASA Astrophysics Data System (ADS)

    Panagiotou, Stylianos C.; Rizogiannis, Constantinos; Katsoulis, Stavros; Lampropoulos, Vassilis; Kanellopoulos, Sotirios; Thomopoulos, Stelios C. A.

    2015-06-01

    Oculus Sea is a complete solution regarding maritime surveillance and communications at Local as well as Central Command and Control level. It includes a robust and independent track fusion service whose main functions include: 1) Interaction with the User to suggest the fusion of two or more tracks, confirm Track ID and Vessel Metadata creation for the fused track, and suggest de-association of two tracks 2) Fusion of same vessel tracks arriving simultaneously from multiple radar sensors featuring track Association, track Fusion of associated tracks to produce a more accurate track, and Multiple tracking filters and fusion algorithms 3) Unique Track ID Generator for each fused track 4) Track Dissemination Service. Oculus Sea Track Fusion Service adopts a system architecture where each sensor is associated with a Kalman estimator/tracker that obtains an estimate of the state vector and its respective error covariance matrix. Finally, at the fusion center, association and track state estimation fusion are carried out. The expected benefits of this system include multi-sensor information fusion, enhanced spatial resolution, and improved target detection.

  8. Vaccine resource tracking systems.

    PubMed

    Leach-Kemon, Katherine; Graves, Casey M; Johnson, Elizabeth K; Lavado, Rouselle F; Hanlon, Michael; Haakenstad, Annie

    2014-09-22

    From 1999 to 2010, annual disbursements of development assistance for health for vaccinations increased from $0.5 billion to $2.0 billion (all financial values USD 2010). In its 2012 Global Vaccine Action Plan (GVAP), the World Health Assembly recommended establishing a comprehensive vaccination resource tracking system to better understand the source and recipients of these funds, and ultimately their impact on outcomes. This systematic review aims to respond to the GVAP recommendation in reviewing and assessing the state of the data and literature on vaccination resource tracking. We scrutinized all relevant vaccination resource tracking systems identified in the literature and by practitioners in the field. We examined schemes used elsewhere in the health sector and by other sectors. Informant interviews were also conducted to determine what data exists and how it might be utilized. With this information, we completed a qualitative assessment of existing approaches to vaccination resources tracking. Tracking systems provide information about some vaccine-related activity in the majority of low- and middle-income countries. Data are generally available for the period of 2006-2010. Levels of granularity vary. Interviewees were concerned about the degree of rigor used to validate the data and the lack of verification. Data are often presented in tabular form, which may be unwieldy for non-technical audiences. The schemes currently in place to track the resources available for vaccinations were fairly advanced relative to other mechanisms in the health sector. Nonetheless, the coverage, validity, and accessibility of vaccination resource tracking data could be ameliorated. Establishing improved feedback loops and verification mechanisms that connect country-level administrators and the international organizations that support reporting efforts would enhance data quality.

  9. TAGGING, TRACKING AND LOCATING WITHOUT GPS

    SciTech Connect

    Cordaro, J.; Coleman, T.; Shull, D.

    2012-07-08

    The Savannah River National Laboratory (SRNL) was requested to lead a Law Enforcement Working Group that was formed to collaborate on common operational needs. All agencies represented on the working group ranked their need to tag, track, and locate a witting or unwitting target as their highest priority. Specifically, they were looking for technologies more robust than Global Positioning Satellite (GPS), could communicate back to the owner, and worked where normal cell phone communications did not work or were unreliable. SRNL brought together multiple technologies in a demonstration that was held in in various Alaska venues, including metropolitan, wilderness, and at-sea that met the working group's requirements. Using prototypical technologies from Boeing, On Ramp, and Fortress, SRNL was able to demonstrate the ability to track personnel and material in all scenarios including indoors, in heavily wooden areas, canyons, and in parking garages. In all cases GPS signals were too weak to measure. Bi-directional communication was achieved in areas that Wi-Fi, cell towers, or traditional radios would not perform. The results of the exercise will be presented. These technologies are considered ideal for tracking high value material such has nuclear material with a platform that allows seamless tracking anywhere in the world, indoors or outdoors.

  10. TRACKING CLEAN UP AT HANFORD

    SciTech Connect

    CONNELL, C.W.

    2005-05-27

    The Hanford Federal Facility Agreement and Consent Order, known as the ''Tri-Party Agreement'' (TPA), is a legally binding agreement among the US Department of Energy (DOE), The Washington State Department of Ecology, and the US Environmental Protection Agency (EPA) for cleaning up the Hanford Site. Established in the 1940s to produce material for nuclear weapons as part of the Manhattan Project, Hanford is often referred to as the world's large environmental cleanup project. The Site covers more than 580 square miles in a relatively remote region of southeastern Washington state in the US. The production of nuclear materials at Hanford has left a legacy of tremendous proportions in terms of hazardous and radioactive waste. From a waste-management point of view, the task is enormous: 1700 waste sites; 450 billion gallons of liquid waste; 70 billion gallons of contaminated groundwater; 53 million gallons of tank waste; 9 reactors; 5 million cubic yards of contaminated soil; 22 thousand drums of mixed waste; 2.3 tons of spent nuclear fuel; and 17.8 metric tons of plutonium-bearing material and this is just a partial listing. The agreement requires that DOE provide the results of analytical laboratory and non-laboratory tests/readings to the lead regulatory agency to help guide then in making decisions. The agreement also calls for each signatory to preserve--for at least ten years after the Agreement has ended--all of the records in it, or its contractors, possession related to sampling, analysis, investigations, and monitoring conducted. The Action Plan that supports the TPA requires that Ecology and EPA have access to all data that is relevant to work performed, or to be performed, under the Agreement. Further, the Action Plan specifies two additional requirements: (1) that EPA, Ecology and their respective contractor staffs have access to all the information electronically, and (2) that the databases are accessible to, and used by, all personnel doing TPA

  11. 10 CFR 32.201 - Serialization of nationally tracked sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Serialization of nationally tracked sources. 32.201 Section 32.201 Energy NUCLEAR REGULATORY COMMISSION SPECIFIC DOMESTIC LICENSES TO MANUFACTURE OR TRANSFER CERTAIN ITEMS CONTAINING BYPRODUCT MATERIAL Specifically Licensed Items § 32.201 Serialization of...

  12. Metabonomics for detection of nuclear materials processing.

    SciTech Connect

    Alam, Todd Michael; Luxon, Bruce A.; Neerathilingam, Muniasamy; Ansari, S.; Volk, David; Sarkar, S.; Alam, Mary Kathleen

    2010-08-01

    Tracking nuclear materials production and processing, particularly covert operations, is a key national security concern, given that nuclear materials processing can be a signature of nuclear weapons activities by US adversaries. Covert trafficking can also result in homeland security threats, most notably allowing terrorists to assemble devices such as dirty bombs. Existing methods depend on isotope analysis and do not necessarily detect chronic low-level exposure. In this project, indigenous organisms such as plants, small mammals, and bacteria are utilized as living sensors for the presence of chemicals used in nuclear materials processing. Such 'metabolic fingerprinting' (or 'metabonomics') employs nuclear magnetic resonance (NMR) spectroscopy to assess alterations in organismal metabolism provoked by the environmental presence of nuclear materials processing, for example the tributyl phosphate employed in the processing of spent reactor fuel rods to extract and purify uranium and plutonium for weaponization.

  13. Nuclear Speckles

    PubMed Central

    Spector, David L.; Lamond, Angus I.

    2011-01-01

    Nuclear speckles, also known as interchromatin granule clusters, are nuclear domains enriched in pre-mRNA splicing factors, located in the interchromatin regions of the nucleoplasm of mammalian cells. When observed by immunofluorescence microscopy, they usually appear as 20–50 irregularly shaped structures that vary in size. Speckles are dynamic structures, and their constituents can exchange continuously with the nucleoplasm and other nuclear locations, including active transcription sites. Studies on the composition, structure, and dynamics of speckles have provided an important paradigm for understanding the functional organization of the nucleus and the dynamics of the gene expression machinery. PMID:20926517

  14. Nuclear reprogramming.

    PubMed

    Halley-Stott, Richard P; Pasque, Vincent; Gurdon, J B

    2013-06-01

    There is currently particular interest in the field of nuclear reprogramming, a process by which the identity of specialised cells may be changed, typically to an embryonic-like state. Reprogramming procedures provide insight into many mechanisms of fundamental cell biology and have several promising applications, most notably in healthcare through the development of human disease models and patient-specific tissue-replacement therapies. Here, we introduce the field of nuclear reprogramming and briefly discuss six of the procedures by which reprogramming may be experimentally performed: nuclear transfer to eggs or oocytes, cell fusion, extract treatment, direct reprogramming to pluripotency and transdifferentiation.

  15. 10 CFR Appendix E to Part 20 - Nationally Tracked Source Thresholds

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Nationally Tracked Source Thresholds E Appendix E to Part 20 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Pt. 20, App. E Appendix E to Part 20— Nationally Tracked Source Thresholds The Terabecquerel (TBq) values are the...

  16. 10 CFR Appendix E to Part 20 - Nationally Tracked Source Thresholds

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Nationally Tracked Source Thresholds E Appendix E to Part 20 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Pt. 20, App. E Appendix E to Part 20— Nationally Tracked Source Thresholds The Terabecquerel (TBq) values are the...

  17. Development of the Open Items Tracking System

    SciTech Connect

    Riggi, V.

    1994-06-01

    The West Valley Demonstration Project, located on the site of the only commercial nuclear fuel reprocessing facility to have operated in USA, has the directed objectives of solidifying the high-level radioactive waste into a durable, solid form for shipment; decontaminating and decommissioning the tanks and facilities; and disposing of the resulting low-level and transuranic wastes. Since an escalating trend of open work items was noticed in the Fall of 1988, and there was no control mechanism for tracking and closing the open items, a Work Control System was developed for this purpose. It is self-contained system on a mainframe ARTEMIS 9000, which tracks, monitors, and closes out external commitments in a timely manner. Audits, surveillances, site appraisals, preventive maintenance, instrument calibration recall, and scheduling are covered.

  18. Robust superpixel tracking.

    PubMed

    Fan Yang; Huchuan Lu; Ming-Hsuan Yang

    2014-04-01

    While numerous algorithms have been proposed for object tracking with demonstrated success, it remains a challenging problem for a tracker to handle large appearance change due to factors such as scale, motion, shape deformation, and occlusion. One of the main reasons is the lack of effective image representation schemes to account for appearance variation. Most of the trackers use high-level appearance structure or low-level cues for representing and matching target objects. In this paper, we propose a tracking method from the perspective of midlevel vision with structural information captured in superpixels. We present a discriminative appearance model based on superpixels, thereby facilitating a tracker to distinguish the target and the background with midlevel cues. The tracking task is then formulated by computing a target-background confidence map, and obtaining the best candidate by maximum a posterior estimate. Experimental results demonstrate that our tracker is able to handle heavy occlusion and recover from drifts. In conjunction with online update, the proposed algorithm is shown to perform favorably against existing methods for object tracking. Furthermore, the proposed algorithm facilitates foreground and background segmentation during tracking.

  19. (Nuclear theory). [Research in nuclear physics

    SciTech Connect

    Haxton, W.

    1990-01-01

    This report discusses research in nuclear physics. Topics covered in this paper are: symmetry principles; nuclear astrophysics; nuclear structure; quark-gluon plasma; quantum chromodynamics; symmetry breaking; nuclear deformation; and cold fusion. (LSP)

  20. Nuclear battlefields

    SciTech Connect

    Arkin, W.M.; Fieldhouse, R.W.

    1985-01-01

    This book provides complete data on the nuclear operations and research facilities in the U.S.A., the U.S.S.R., France, China and the U.K. It describes detailed estimates on the U.S.S.R.'s nuclear stockpile for over 500 locations. It shows how non-nuclear countries cooperate with the world-wide war machine. And it maps the U.S. nuclear facilities from Little America, WY, and Charleston, SC, to the battleships patroling the world's oceans and subs stalking under the sea. The data were gathered from unclassified sources through the Freedom of Information Act, from data supplied to military installations, and from weapons source books. It provides guidance for policymakers, government and corporate officials.

  1. NUCLEAR REACTOR

    DOEpatents

    Sherman, J.; Sharbaugh, J.E.; Fauth, W.L. Jr.; Palladino, N.J.; DeHuff, P.G.

    1962-10-23

    A nuclear reactor incorporating seed and blanket assemblies is designed. Means are provided for obtaining samples of the coolant from the blanket assemblies and for varying the flow of coolant through the blanket assemblies. (AEC)

  2. Nuclear Disarmament.

    ERIC Educational Resources Information Center

    Johnson, Christopher

    1982-01-01

    Material about nuclear disarmament and the arms race should be included in secondary school curricula. Teachers can present this technical, controversial, and frightening material in a balanced and comprehensible way. Resources for instructional materials are listed. (PP)

  3. Adaptive tracking system

    NASA Astrophysics Data System (ADS)

    Kulpa, Krzysztof; Centkowski, Grzymislaw; Wojtkiewicz, Andrzej; Klembowski, Wieslaw

    The paper presents an efficient adaptive tracking system for surveillance ATC radar. The system was implemented in software on an INTEL-80286-based machine. The tracking filter was built as a cascade of the Kalman filters and maneuver correction FIR filter. It ensures fast adaptation to maneuvers, low prediction error, and low computational complexity. The maneuver detector, combined with a measurement error variance estimator, controls the filter gains according to the detected maneuver and selects the proper size of a plot-track correlation gate. The system features high accuracy and throughput. It can adapt to changes of false plot density, detection probability, and variance of measurement error, as well as to pilot-induced maneuvers.

  4. Tracks to therapy

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.

    1999-01-01

    Studies of the structure of particle tracks have led to models of track effects based on radial dose and radiobiological target theory that have been very successful in describing and predicting track effects in physical, chemical, and biological systems. For describing mammalian cellular inactivation two inactivation modes are required, called gamma-kill and ion-kill, the first due to synergistic effects of delta rays from adjacent ion paths thus resembling the effects from gamma rays, and the second to the effects of single ion transits through a cell nucleus. The ion-kill effect is more severe, where the fraction of cells experiencing ion kill is responsible for a decrease in the oxygen enhancement ratio, and an increase in relative biological effectiveness, but these are accompanied by loss of repair, hence to a reduction in the efficiency of fractionation in high LET therapy, as shown by our calculations for radiobiological effects in the "spread out Bragg Peak".

  5. Tracking system study

    NASA Technical Reports Server (NTRS)

    Dennis, A. R.; Tabak, D.; Gifford, L. D.; Mednick, H. M.; Buchert, J.

    1969-01-01

    A digital computer program was generated which mathematically describes an optimal estimator-controller technique as applied to the control of antenna tracking systems used by NASA. Simulation studies utilizing this program were conducted using the IBM 360/91 computer. The basic ideas of applying optimal estimator-controller techniques to antenna tracking systems are discussed. A survey of existing tracking methods is given along with shortcomings and inherent errors. It is explained how these errors can be considerably reduced if optimal estimation and control are used. The modified programs generated in this project are described and the simulation results are summarized. The new algorithms for direct synthesis and stabilization of the systems including nonlinearities, are presented.

  6. Deep 6-DOF Tracking.

    PubMed

    Garon, Mathieu; Lalonde, Jean-Francois

    2017-11-01

    We present a temporal 6-DOF tracking method which leverages deep learning to achieve state-of-the-art performance on challenging datasets of real world capture. Our method is both more accurate and more robust to occlusions than the existing best performing approaches while maintaining real-time performance. To assess its efficacy, we evaluate our approach on several challenging RGBD sequences of real objects in a variety of conditions. Notably, we systematically evaluate robustness to occlusions through a series of sequences where the object to be tracked is increasingly occluded. Finally, our approach is purely data-driven and does not require any hand-designed features: robust tracking is automatically learned from data.

  7. Tracks to therapy

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.

    1999-01-01

    Studies of the structure of particle tracks have led to models of track effects based on radial dose and radiobiological target theory that have been very successful in describing and predicting track effects in physical, chemical, and biological systems. For describing mammalian cellular inactivation two inactivation modes are required, called gamma-kill and ion-kill, the first due to synergistic effects of delta rays from adjacent ion paths thus resembling the effects from gamma rays, and the second to the effects of single ion transits through a cell nucleus. The ion-kill effect is more severe, where the fraction of cells experiencing ion kill is responsible for a decrease in the oxygen enhancement ratio, and an increase in relative biological effectiveness, but these are accompanied by loss of repair, hence to a reduction in the efficiency of fractionation in high LET therapy, as shown by our calculations for radiobiological effects in the "spread out Bragg Peak".

  8. Nuclear Nonproliferation

    SciTech Connect

    Atkins-Duffin, C E

    2008-12-10

    With an explosion equivalent of about 20kT of TNT, the Trinity test was the first demonstration of a nuclear weapon. Conducted on July 16, 1945 in Alamogordo, NM this site is now a Registered National Historic Landmark. The concept and applicability of nuclear power was demonstrated on December 20, 1951 with the Experimental Breeder Reactor Number One (EBR-1) lit four light bulbs. This reactor is now a Registered National Historic Landmark, located near Arco, ID. From that moment forward it had been clearly demonstrated that nuclear energy has both peaceful and military applications and that the civilian and military fuel cycles can overlap. For the more than fifty years since the Atoms for Peace program, a key objective of nuclear policy has been to enable the wider peaceful use of nuclear energy while preventing the spread of nuclear weapons. Volumes have been written on the impact of these two actions on the world by advocates and critics; pundits and practioners; politicians and technologists. The nations of the world have woven together a delicate balance of treaties, agreements, frameworks and handshakes that are representative of the timeframe in which they were constructed and how they have evolved in time. Collectively these vehicles attempt to keep political will, nuclear materials and technology in check. This paper captures only the briefest abstract of the more significant aspects on the Nonproliferation Regime. Of particular relevance to this discussion is the special nonproliferation sensitivity associated with the uranium isotope separation and spent fuel reprocessing aspects of the nuclear fuel cycle.

  9. Nuclear Data

    SciTech Connect

    White, Morgan C.

    2014-01-23

    PowerPoint presentation targeted for educational use. Nuclear data comes from a variety of sources and in many flavors. Understanding where the data you use comes from and what flavor it is can be essential to understand and interpret your results. This talk will discuss the nuclear data pipeline with particular emphasis on providing links to additional resources that can be used to explore the issues you will encounter.

  10. Nuclear cardiac

    SciTech Connect

    Slutsky, R.; Ashburn, W.L.

    1982-01-01

    The relationship between nuclear medicine and cardiology has continued to produce a surfeit of interesting, illuminating, and important reports involving the analysis of cardiac function, perfusion, and metabolism. To simplify the presentation, this review is broken down into three major subheadings: analysis of myocardial perfusion; imaging of the recent myocardial infarction; and the evaluation of myocardial function. There appears to be an increasingly important relationship between cardiology, particularly cardiac physiology, and nuclear imaging techniques. (KRM)

  11. Nuclear accidents

    SciTech Connect

    Mobley, J.A.

    1982-05-01

    A nuclear accident with radioactive contamination can happen anywhere in the world. Because expert nuclear emergency teams may take several hours to arrive at the scene, local authorities must have a plan of action for the hours immediately following an accident. The site should be left untouched except to remove casualties. Treatment of victims includes decontamination and meticulous wound debridement. Acute radiation syndrome may be an overwhelming sequela.

  12. Nuclear telemedicine

    NASA Astrophysics Data System (ADS)

    Morrison, R. T.; Szasz, I. J.

    1990-06-01

    Diagnostic nuclear medicine patient images have been transniitted for 8 years from a regional conununity hospital to a university teaching hospital 700 kiloinetres away employing slow scan TV and telephone. Transruission and interpretation were done at the end of each working day or as circumstances required in cases of emergencies. Referring physicians received the nuclear medicine procedure report at the end of the completion day or within few minutes of completion in case of emergency procedures. To date more than 25 patient studies have been transmitted for interpretation. Blinded reinterpretation of the original hard copy data of 350 patient studies resulted in 100 agreement with the interpretation of transmitted data. This technique provides high quality diagnostic and therapeutic nuclear medicine services in remote hospitals where the services of an on-site nuclear physician is not available. 2. HISTORY Eight years ago when the nuclear medicine physician at Trail Regional Hospital left the Trail area and an other could not be recruited we examined the feasibility of image transmission by phone for interpretation since closing the department would have imposed unacceptable physical and financial hardship and medical constraints on the patient population the nearest nuclear medicine facility was at some 8 hours drive away. In hospital patients would have to be treated either based purely on physical findings or flown to Vancouver at considerable cost to the health care system (estimated cost $1500.

  13. Spirit Leaves Telling Tracks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Scientists have found clues about the nature of martian soil through analyzing wheel marks from the Mars Exploration Rover Spirit in this image. The image was taken by Spirit's rear hazard-identification camera just after the rover drove approximately 1 meter (3 feet) northwest off the Columbia Memorial Station (lander platform) early Thursday morning. That the wheel tracks are shallow indicates the soil has plenty of strength to support the moving rover. The well-defined track characteristics suggest the presence of very fine particles in the martian soil (along with larger particles). Scientists also think the soil may have some cohesive properties.

  14. Simple front tracking

    SciTech Connect

    Glimm, J.; Grove, J.W.; Li, X.; Zhao, N.

    1999-04-01

    A new and simplified front tracking algorithm has been developed as an aspect of the extension of this algorithm to three dimensions. Here the authors emphasize two main results: (1) a simplified description of the microtopology of the interface, based on interface crossings with cell block edges, and (2) an improved algorithm for the interaction of a tracked contact discontinuity with an untracked shock wave. For the latter question, they focus on the post interaction jump at the contact, which is a purely 1D issue. Comparisons to other methods, including the level set method, are included.

  15. Cell tracking using nanoparticles.

    PubMed

    Vaccaro, Dennis E; Yang, Meiheng; Weinberg, James S; Reinhardt, Christopher P; Groman, Ernest V

    2008-09-01

    Tracking cells in regenerative medicine is becoming increasingly important for basic cell therapy science, for cell delivery optimization and for accurate biodistribution studies. This report describes nanoparticles that utilize stable-isotope metal labels for multiple detection technologies in preclinical studies. Cells labeled with nanoparticles can be imaged by electron microscopy, fluorescence, and magnetic resonance. The nanoparticle-labeled cells can be quantified by neutron activation, thereby allowing, with the use of standard curves, the determination of the number of labeled cells in tissue samples from in vivo sources. This report describes the characteristics of these nanoparticles and methods for using these nanoparticles to label and track cells.

  16. Interferometric star tracking.

    PubMed

    Decou, A B

    1974-02-01

    A new star-tracking technique based on interferometry is described and analyzed in detail. A heuristic comparison is made with traditional star-tracking methods that demonstrates several advantages in the interferometric approach for very high accuracy systems. A detailed error analysis is performed on several versions of the system that use all solid-state detection. One such system is shown to have a potential accuracy of +/-0.01 sec of arc using a small optical system and state-of-the-art components. Applications of the new system in large orbiting astronomical observatories and deep space laser communications systems are also discussed.

  17. Curved track segment finding using Tiny Triplet Finder (TTF)

    SciTech Connect

    Wu, Jin-Yuan; Wang, M.; Gottschalk, E.; Shi, Z.; /Fermilab

    2006-11-01

    We describe the applications of a track segment recognition scheme called the Tiny Triplet Finder (TTF) that involves the grouping of three hits satisfying a constraint forming of a track segment. The TTF was originally developed solving straight track segment finding problem, however, it is also suitable in many curved track segment finding problems. The examples discussed in this document are among popular detector layouts in high-energy/nuclear physics experiments. Although it is not practical to find a universal recipe for arbitrary detector layouts, the method of the TTF application is illustrated via the discussion of the examples. Generally speaking, whenever the data item to be found in a pattern recognition problem contains two free parameters, and if the constraint connecting the measurements and the two free parameters has an approximate shift invariant property, the Tiny Triplet Finder can be used.

  18. Tracking Politics with POWER

    ERIC Educational Resources Information Center

    Moreira, Silvio; Batista, David S.; Carvalho, Paula; Couto, Francisco M.; Silva, Mario J.

    2013-01-01

    Purpose: POWER is an ontology of political processes and entities. It is designed for tracking politicians, political organizations and elections, both in mainstream and social media. The aim of this paper is to propose a data model to describe political agents and their relations over time. Design/methodology/approach: The authors propose a data…

  19. Tracking Speech Sound Acquisition

    ERIC Educational Resources Information Center

    Powell, Thomas W.

    2011-01-01

    This article describes a procedure to aid in the clinical appraisal of child speech. The approach, based on the work by Dinnsen, Chin, Elbert, and Powell (1990; Some constraints on functionally disordered phonologies: Phonetic inventories and phonotactics. "Journal of Speech and Hearing Research", 33, 28-37), uses a railway idiom to track gains in…

  20. Energy Tracking Diagrams

    ERIC Educational Resources Information Center

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-01-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the "Next Generation Science Standards," the primary conceptual learning goal is for learners to conserve energy as they "track" the transfers and transformations of energy within, into, or out of the system of…

  1. Dust Devil Tracks

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called

  2. Registration and Tracking Report

    DTIC Science & Technology

    2006-02-01

    Single No Partial Yes Appearance Tracking [66] Single No Partial Yes Layering [67] Multi No Full No Bramble [68] Multi Yes Full No EigenTracker [14...representations.” IEEE Trans. on Pattern Analysis and Machine Intelligence, 24(1):75-89, 2002. [68] M. Isard and J. MacCormick. ” BraMBLe : A Bayesian Multiple-Blob

  3. Dust Devil Tracks

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called

  4. Tracks Inside 'Endurance'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This picture from the front hazard-avoidance camera on NASA's Mars Exploration Rover Opportunity shows rover wheel tracks on the inner slope of 'Endurance Crater.' Opportunity took the image on sol 188 (Aug. 4, 2004), before transmitting it and other data to the European Space Agency's Mars Express orbiter. The orbiter then relayed the data to Earth.

  5. TRACKING Trounces Test Scores

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    This article presents an adaptation of an article from School Board News, January 6, 2004 edition. The article describes the effort of de-tracking students of varying ability levels, made by officials of South Side High School, in Rockville Centre, New York, and Noble High School, in North Berwick, Maine. Officials from both schools say that the…

  6. Eliminating Tracking Successfully.

    ERIC Educational Resources Information Center

    Swartzbaugh, Phil

    1988-01-01

    Describes a Fall 1984 cooperative learning project at a Phoenix, Arizona, junior high school involving three sections of mixed-ability student groupings in reading, English, and math. At year's end, all academic levels (particularly remedial students) in the mixed-ability classes fared better than their counterparts in the tracked classes. By…

  7. Spiral track oven

    SciTech Connect

    Drobilisch, Sandor

    1998-12-20

    Final report on development of a continuously operating oven system in which the parts are progressing automatically on a spiral track for in-line service installation for the production of electronic and/or other components to be heat cured or dried.

  8. Tracking Weather Satellites.

    ERIC Educational Resources Information Center

    Martin, Helen E.

    1996-01-01

    Describes the use of weather satellites in providing an exciting, cohesive framework for students learning Earth and space science and in providing a hands-on approach to technology in the classroom. Discusses the history of weather satellites and classroom satellite tracking. (JRH)

  9. Pseudonoise code tracking loop

    NASA Technical Reports Server (NTRS)

    Laflame, D. T. (Inventor)

    1980-01-01

    A delay-locked loop is presented for tracking a pseudonoise (PN) reference code in an incoming communication signal. The loop is less sensitive to gain imbalances, which can otherwise introduce timing errors in the PN reference code formed by the loop.

  10. Tracking in 4 dimensions

    NASA Astrophysics Data System (ADS)

    Cartiglia, N.; Arcidiacono, R.; Baldassarri, B.; Boscardin, M.; Cenna, F.; Dellacasa, G.; Betta, G.-F. Dalla; Ferrero, M.; Fadeyev, V.; Galloway, Z.; Garbolino, S.; Grabas, H.; Monaco, V.; Obertino, M.; Pancheri, L.; Paternoster, G.; Rivetti, A.; Rolo, M.; Sacchi, R.; Sadrozinski, H.; Seiden, A.; Sola, V.; Solano, A.; Staiano, A.; Ravera, F.; Zatserklyaniy, A.

    2017-02-01

    In this contribution we will review the progresses toward the construction of a tracking system able to measure the passage of charged particles with a combined precision of ∼10 ps and ∼10 μm, either using a single type of sensor, able to concurrently measure position and time, or a combination of position and time sensors.

  11. TRACKING Trounces Test Scores

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    This article presents an adaptation of an article from School Board News, January 6, 2004 edition. The article describes the effort of de-tracking students of varying ability levels, made by officials of South Side High School, in Rockville Centre, New York, and Noble High School, in North Berwick, Maine. Officials from both schools say that the…

  12. Tracking the Invisible Faculty

    ERIC Educational Resources Information Center

    Gravois, John

    2006-01-01

    For decades it has been happening everywhere in academe, but nowhere in particular. The sweeping shift toward non-tenure-track academic labor has been one of the most worried-over trends in American higher education. But it has been charted mostly with broad-brush data, which give little indication of the trend's progress at the institutional…

  13. Asset tracking systems.

    PubMed

    2006-11-01

    Asset tracking systems are used in healthcare to find objects--medical devices and other hospital equipment--and to record the physical location of those objects over time. Interest in asset tracking is growing daily, but the technology is still evolving, and so far very few systems have been implemented in hospitals. This situation is likely to change over the next few years, at which point many hospitals will be faced with choosing a system. We evaluated four asset tracking systems from four suppliers: Agility Healthcare Solutions, Ekahau, Radianse, and Versus Technology. We judged the systems' performance for two "levels" of asset tracking. The first level is basic locating--simply determining where in the facility an item can be found. This may be done because the equipment needs routine inspection and preventive maintenance or because it is required for recall purposes; or the equipment may be needed, often urgently, for clinical use. The second level, which is much more involved, is inventory optimization and workflow improvement. This entails analyzing asset utilization based on historical location data to improve the use, distribution, and processing of equipment. None of the evaluated products is ideal for all uses--each has strengths and weaknesses. In many cases, hospitals will have to select a product based on their specific needs. For example, they may need to choose between a supplier whose system is easy to install and a supplier whose tags have a long battery operating life.

  14. Eliminating Tracking Successfully.

    ERIC Educational Resources Information Center

    Swartzbaugh, Phil

    1988-01-01

    Describes a Fall 1984 cooperative learning project at a Phoenix, Arizona, junior high school involving three sections of mixed-ability student groupings in reading, English, and math. At year's end, all academic levels (particularly remedial students) in the mixed-ability classes fared better than their counterparts in the tracked classes. By…

  15. Tracking Speech Sound Acquisition

    ERIC Educational Resources Information Center

    Powell, Thomas W.

    2011-01-01

    This article describes a procedure to aid in the clinical appraisal of child speech. The approach, based on the work by Dinnsen, Chin, Elbert, and Powell (1990; Some constraints on functionally disordered phonologies: Phonetic inventories and phonotactics. "Journal of Speech and Hearing Research", 33, 28-37), uses a railway idiom to track gains in…

  16. Getting back on Track

    ERIC Educational Resources Information Center

    Ringland, Pam

    2007-01-01

    This September saw the start of Back on Track, a pioneering pilot course for young people with mental health problems who would like to return to learning or work. The course is being run in Portsmouth by local further education (FE) colleges, with Highbury College the main provider, in collaboration with Headspace, the Portsmouth City Mental…

  17. Tracking Politics with POWER

    ERIC Educational Resources Information Center

    Moreira, Silvio; Batista, David S.; Carvalho, Paula; Couto, Francisco M.; Silva, Mario J.

    2013-01-01

    Purpose: POWER is an ontology of political processes and entities. It is designed for tracking politicians, political organizations and elections, both in mainstream and social media. The aim of this paper is to propose a data model to describe political agents and their relations over time. Design/methodology/approach: The authors propose a data…

  18. Energy Tracking Diagrams

    ERIC Educational Resources Information Center

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-01-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the "Next Generation Science Standards," the primary conceptual learning goal is for learners to conserve energy as they "track" the transfers and transformations of energy within, into, or out of the system of…

  19. GEOS-3 Doppler difference tracking

    NASA Technical Reports Server (NTRS)

    Rosenbaum, B.

    1977-01-01

    The Doppler difference method as applied to track the GEOS 3 spacecraft is discussed. In this method a pair of 2 GHz ground tracking stations simultaneously track a spacecraft beacon to generate an observable signal in which bias and instability of the carrier frequency cancel. The baselines are formed by the tracking sites at Bermuda, Rosman, and Merritt Island. Measurements were made to evaluate the effectiveness of the Doppler differencing procedure in tracking a beacon target with the high dynamic rate of the GEOS 3 orbit. Results indicate the precision of the differenced data to be at a level comparable to the conventional precise two way Doppler tracking.

  20. BNSF RAILROAD MAIN TRACK 1 AND THE UNION PACIFIC TRACK ...

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

    BNSF RAILROAD MAIN TRACK 1 AND THE UNION PACIFIC TRACK CUTTING THROUGH BEDROCK AROUND SULLIVAN’S CURVE. VIEW TO THE WEST. 102 - Burlington Northern Santa Fe Railroad, Cajon Subdivision, Between Cajon Summit and Keenbrook, Devore, San Bernardino County, CA

  1. FINE GRAIN NUCLEAR EMULSION

    DOEpatents

    Oliver, A.J.

    1962-04-24

    A method of preparing nuclear track emulsions having mean grain sizes less than 0.1 microns is described. The method comprises adding silver nitrate to potassium bromide at a rate at which there is always a constant, critical excess of silver ions. For minimum size grains, the silver ion concentration is maintained at the critical level of about pAg 2.0 to 5.0 during prectpitation, pAg being defined as the negative logarithm of the silver ion concentration. It is preferred to eliminate the excess silver at the conclusion of the precipitation steps. The emulsion is processed by methods in all other respects generally similar to the methods of the prior art. (AEC)

  2. Nuclear Forensics and Attribution for Improved Energy Security: The Use of Taggants in Nuclear Fuel

    SciTech Connect

    Kristo, M J; Robel, M; Hutcheon, I D

    2007-04-05

    The Global Nuclear Energy Partnership (GNEP), recently announced by DOE Secretary Bodman, poses significant new challenges with regard to securing, safeguarding, monitoring and tracking nuclear materials. In order to reduce the risk of nuclear proliferation, new technologies must be developed to reduce the risk that nuclear material can be diverted from its intended use. Regardless of the specific nature of the fuel cycle, nuclear forensics and attribution will play key roles to ensure the effectiveness of nonproliferation controls and to deter the likelihood of illicit activities. As the leader of the DHS nuclear and radiological pre-detonation attribution program, LLNL is uniquely positioned to play a national leadership role in this effort. Ensuring that individuals or organizations engaged in illicit trafficking are rapidly identified and apprehended following theft or diversion of nuclear material provides a strong deterrent against unlawful activities. Key to establishing this deterrent is developing the ability to rapidly and accurately determine the identity, source and prior use history of any interdicted nuclear material. Taggants offer one potentially effective means for positively identifying lost or stolen nuclear fuels. Taggants are materials that can be encoded with a unique signature and introduced into nuclear fuel during fuel fabrication. During a nuclear forensics investigation, the taggant signature can be recovered and the nuclear material identified through comparison with information stored in an appropriate database. Unlike serial numbers or barcodes, microtaggants can provide positive identification with only partial recovery, providing extreme resistance to any attempt to delete or alter them.

  3. Nuclear risk

    SciTech Connect

    Levenson, M.

    1989-01-01

    The title of our session, Nuclear Risk Versus Other Power Options, is provocative. It is also a title with different meanings to different people. To the utility chief executive officer, nuclear power is a high-risk financial undertaking because of political and economic barriers to cost recovery. To the utility dispatcher, it is a high-risk future power source since plant completion and start-up dates can be delayed for very long times due to uncertain legal and political issues. To the environmentalist, concerned about global effects such as greenhouse and acid rain, nuclear power is a relatively low risk energy source. To the financial people, nuclear power is a cash cow turned sour because of uncertainties as to what new plants will cost and whether they will even be allowed to operate. The statistics on risk are known and the results of probability risk assessment calculations of risks are known. The challenge is not to make nuclear power safer, it is already one of the safest, if not the safest, source of power currently available. The challenge is to find a way to communicate this to the public.

  4. GPS Metric Tracking Unit

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As Global Positioning Satellite (GPS) applications become more prevalent for land- and air-based vehicles, GPS applications for space vehicles will also increase. The Applied Technology Directorate of Kennedy Space Center (KSC) has developed a lightweight, low-cost GPS Metric Tracking Unit (GMTU), the first of two steps in developing a lightweight, low-cost Space-Based Tracking and Command Subsystem (STACS) designed to meet Range Safety's link margin and latency requirements for vehicle command and telemetry data. The goals of STACS are to improve Range Safety operations and expand tracking capabilities for space vehicles. STACS will track the vehicle, receive commands, and send telemetry data through the space-based asset, which will dramatically reduce dependence on ground-based assets. The other step was the Low-Cost Tracking and Data Relay Satellite System (TDRSS) Transceiver (LCT2), developed by the Wallops Flight Facility (WFF), which allows the vehicle to communicate with a geosynchronous relay satellite. Although the GMTU and LCT2 were independently implemented and tested, the design collaboration of KSC and WFF engineers allowed GMTU and LCT2 to be integrated into one enclosure, leading to the final STACS. In operation, GMTU needs only a radio frequency (RF) input from a GPS antenna and outputs position and velocity data to the vehicle through a serial or pulse code modulation (PCM) interface. GMTU includes one commercial GPS receiver board and a custom board, the Command and Telemetry Processor (CTP) developed by KSC. The CTP design is based on a field-programmable gate array (FPGA) with embedded processors to support GPS functions.

  5. Tracking Virtual Trajectories

    NASA Technical Reports Server (NTRS)

    Stone, Leland S.; Beutter, Brent R.; Lorenceau, Jean D.; Null, Cynthia H. (Technical Monitor)

    1996-01-01

    Current models of smooth pursuit eye movements assume that it is largely driven by retinal image motion. We tested this hypothesis by measuring pursuit of elliptical motion (3.2s, 0.9 Hz, 1.4 deg x 1.6 deg, 4 randomly interleaved phases) of either a small spot ("real" motion) or of a line-figure diamond viewed through apertures such that only the motion of four isolated oblique line segments was visible ("virtual" motion). Each segment moved sinusoidally along a linear trajectory yet subjects perceived a diamond moving along an elliptical path behind the aperture. We found, as expected, that real motion produced accurate tracking (N = 2) with mean gain (over horizontal and vertical) of 0.9, mean phase of -6 deg (lag), mean relative phase (H vs V) of 90 +/- 8 deg (RMS error). Virtual motion behind an X-shaped aperture (N= 4 with one naive) yielded a mean gain of 0.7, mean phase of -11 deg, mean relative phase of 87 +/- 15 deg. We also measured pursuit with the X-shaped aperture using a higher segment luminance which prevents the segments from being grouped into a coherently moving diamond while keeping the motion otherwise identical. In this incoherent case, the same four subjects no longer showed consistent elliptical tracking (RMS error in relative phase rose to 60 deg) suggesting that perceptual coherence is critical. Furthermore, to rule out tracking of the centroid, we also used vertical apertures so that all segment motion was vertical (N = 3). This stimulus still produced elliptical tracking (mean relative phase of 84 +/- 19 deg), albeit with a lower gain (0.6). These data show that humans can track moving objects reasonably accurately even when the trajectory can only be derived by spatial integration of motion signals. Models that merely seek to minimize retinal or local stimulus motion cannot explain these results.

  6. TRACKING SURPLUS PLUTONIUM FROM WEAPONS TO DISPOSITION

    SciTech Connect

    Allender, J.; Beams, J.; Sanders, K.; Myers, L.

    2013-07-16

    Supporting nuclear nonproliferation and global security principles, beginning in 1994 the United States has withdrawn more than 50 metric tons (MT) of government-controlled plutonium from potential use in nuclear weapons. The Department of Energy (DOE), including the National Nuclear Security Administration, established protocols for the tracking of this "excess" and "surplus" plutonium, and for reconciling the current storage and utilization of the plutonium to show that its management is consistent with the withdrawal policies. Programs are underway to ensure the safe and secure disposition of the materials that formed a major part of the weapons stockpile during the Cold War, and growing quantities have been disposed as waste, after which they are not included in traditional nuclear material control and accountability (NMC&A) data systems. A combination of resources is used to perform the reconciliations that form the basis for annual reporting to DOE, to U.S. Department of State, and to international partners including the International Atomic Energy Agency.

  7. Atomistic simulation of track formation by energetic ions in zircon

    SciTech Connect

    Moreira, Pedro A.F.P.; Devanathan, Ram; Weber, William J

    2010-01-01

    We have performed classical molecular dynamics simulations of fission track formation in zircon. We simulated the passage of a swift heavy ion through crystalline zircon using cylindrical thermal spikes with energy deposition (dE/dx) of 2.5-12.8 keV nm{sup -1} and a radius of 3 nm. At a low dE/dx of 2.55 keV nm{sup -1}, the structural damage recovered almost completely and a damage track was not produced. At higher values of dE/dx, tracks were observed and the radius of the track increased with increasing dE/dx. Our structural analysis shows amorphization in the core of the track and phase separation into Si-rich regions near the center of the track and Zr-rich regions near the periphery. These simulations establish a threshold dE/dx for fission track formation in zircon that is relevant to thermochronology and nuclear waste immobilization.

  8. Atomistic Simulation of Track Formation by Energetic Recoils in Zircon

    SciTech Connect

    Moreira, Pedro A.; Devanathan, Ramaswami; Weber, William J.

    2010-09-17

    We have performed classical molecular dynamics simulations of fission track formation in zircon. We simulated the passage of a swift heavy ion through crystalline zircon using cylindrical thermal spikes with energy deposition (dE/dx) of 2.5 to 12.8 keV/nm and radius of 3 nm. At a low dE/dx of 2.55 keV/nm, the structural damage recovered almost completely and a damage track was not produced. At higher values of dE/dx, tracks were observed and the radius of the track increased with increasing dE/dx. Our structural analysis shows amorphization in the core of the track and phase separation into Si-rich regions near the center of the track and Zr-rich regions near the periphery. These simulations establish a threshold dE/dx for fission-track formation in zircon that is relevant to thermo-chronology and nuclear waste immobilization.

  9. 31. "FIGURE 310, TRACK LAYOUT (EDWARDS)". Test track footing and ...

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

    31. "FIGURE 3-10, TRACK LAYOUT (EDWARDS)". Test track footing and rail head cross sections. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  10. Nuclear material accounting software for Ukraine

    SciTech Connect

    Doll, M.; Ewing, T.; Lindley, R.; McWilliams, C.; Roche, C.; Sakunov, I.; Walters, G.

    1999-07-26

    Among the needs identified during initial surveys of nuclear facilities in Ukraine was improved accounting software for reporting material inventories to the regulatory body. AIMAS (Automated Inventory/Material Accounting System) is a PC-based application written in Microsoft Access that was jointly designed by an US/Ukraine development team. The design is highly flexible and configurable, and supports a wide range of computing infrastructure needs and facility requirements including situations where networks are not available or reliable. AIMAS has both English and Russian-language options for displays and reports, and it operates under Windows 3.1, 95, or NT 4.0{trademark}. AIMAS functions include basic physical inventory tracking, transaction histories, reporting, and system administration functions (system configuration, security, data backup and recovery). Security measures include multilevel password access control, all transactions logged with the user identification, and system administration control. Interfaces to external modules provide nuclear fuel burn-up adjustment and barcode scanning capabilities for physical inventory taking. AIMAS has been installed at Kiev Institute of Nuclear Research (KINR), South Ukraine Nuclear Power Plant (SUNPP), Kharkov Institute of Physics and Technology (KIPT), Sevastopol Institute of Nuclear Energy and Industry (SINEI), and the Ministry of Environmental Protection and Nuclear Safety/Nuclear Regulatory Administration (MEPNS/NRA). Facility specialists are being trained to use the application to track material movement and report to the national regulatory authority.

  11. Nuclear scales

    SciTech Connect

    Friar, J.L.

    1998-12-01

    Nuclear scales are discussed from the nuclear physics viewpoint. The conventional nuclear potential is characterized as a black box that interpolates nucleon-nucleon (NN) data, while being constrained by the best possible theoretical input. The latter consists of the longer-range parts of the NN force (e.g., OPEP, TPEP, the {pi}-{gamma} force), which can be calculated using chiral perturbation theory and gauged using modern phase-shift analyses. The shorter-range parts of the force are effectively parameterized by moments of the interaction that are independent of the details of the force model, in analogy to chiral perturbation theory. Results of GFMC calculations in light nuclei are interpreted in terms of fundamental scales, which are in good agreement with expectations from chiral effective field theories. Problems with spin-orbit-type observables are noted.

  12. Nuclear astrophysics

    SciTech Connect

    Penionzhkevich, Yu. E.

    2010-08-15

    The International Year of Astronomy 2009 (IYA2009) was declared by the 62nd General Assembly of the United Nations and was also endorsed by UNESCO. Investigations in the realms of particle and nuclear physicsmake a large contribution in the development of our ideas of the properties of the Universe. The present article discusses some problems of the evolution of the Universe, nucleosyntheses, and cosmochronology from the point of view of nuclear and particle physics. Processes occurring in the Universe are compared with the mechanisms of the production and decay of nuclei, as well as with the mechanisms of their interaction at high energies. Examples that demonstrate the potential of nuclearphysics methods for studying cosmic objects and the properties of the Universe are given. The results that come from investigations into nuclear reactions induced by beams of radioactive nuclei and which make it possible to take a fresh look at the nucleosynthesis scenario in the range at light nuclei are presented.

  13. Nuclear waste

    SciTech Connect

    Not Available

    1988-05-01

    This paper discusses how, as part of the Department of Energy's implementation of the Nuclear Waste Policy Act of 1982, DOE is required to investigate a site at Yucca Mountain, Nevada and, if it determines that the site is suitable, recommend to the President its selection for a nuclear waste repository. The Nuclear Regulatory Commission, in considering development of the plan, issued five objections, one of which is DOE's failure to recognize the range of alternative conceptual models of the Yucca Mountain site that can be supported by the limited existing technical data. At the end of the quarter DOE directed its project offices in Washington and Texas to begin orderly phase-out of all site-specific repository activities. Costs for this phase-out are $53 million for the Deaf Smith site and $85 million for the Hanford site.

  14. Performance of automatic scanning microscope for nuclear emulsion experiments

    SciTech Connect

    Güler, A. Murat; Altınok, Özgür

    2015-12-31

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  15. Performance of automatic scanning microscope for nuclear emulsion experiments

    NASA Astrophysics Data System (ADS)

    Güler, A. Murat; Altınok, Özgür

    2015-12-01

    The impressive improvements in scanning technology and methods let nuclear emulsion to be used as a target in recent large experiments. We report the performance of an automatic scanning microscope for nuclear emulsion experiments. After successful calibration and alignment of the system, we have reached 99% tracking efficiency for the minimum ionizing tracks that penetrating through the emulsions films. The automatic scanning system is successfully used for the scanning of emulsion films in the OPERA experiment and plan to use for the next generation of nuclear emulsion experiments.

  16. Nuclear Models

    NASA Astrophysics Data System (ADS)

    Fossión, Rubén

    2010-09-01

    The atomic nucleus is a typical example of a many-body problem. On the one hand, the number of nucleons (protons and neutrons) that constitute the nucleus is too large to allow for exact calculations. On the other hand, the number of constituent particles is too small for the individual nuclear excitation states to be explained by statistical methods. Another problem, particular for the atomic nucleus, is that the nucleon-nucleon (n-n) interaction is not one of the fundamental forces of Nature, and is hard to put in a single closed equation. The nucleon-nucleon interaction also behaves differently between two free nucleons (bare interaction) and between two nucleons in the nuclear medium (dressed interaction). Because of the above reasons, specific nuclear many-body models have been devised of which each one sheds light on some selected aspects of nuclear structure. Only combining the viewpoints of different models, a global insight of the atomic nucleus can be gained. In this chapter, we revise the the Nuclear Shell Model as an example of the microscopic approach, and the Collective Model as an example of the geometric approach. Finally, we study the statistical properties of nuclear spectra, basing on symmetry principles, to find out whether there is quantum chaos in the atomic nucleus. All three major approaches have been rewarded with the Nobel Prize of Physics. In the text, we will stress how each approach introduces its own series of approximations to reduce the prohibitingly large number of degrees of freedom of the full many-body problem to a smaller manageable number of effective degrees of freedom.

  17. Nuclear Models

    SciTech Connect

    Fossion, Ruben

    2010-09-10

    The atomic nucleus is a typical example of a many-body problem. On the one hand, the number of nucleons (protons and neutrons) that constitute the nucleus is too large to allow for exact calculations. On the other hand, the number of constituent particles is too small for the individual nuclear excitation states to be explained by statistical methods. Another problem, particular for the atomic nucleus, is that the nucleon-nucleon (n-n) interaction is not one of the fundamental forces of Nature, and is hard to put in a single closed equation. The nucleon-nucleon interaction also behaves differently between two free nucleons (bare interaction) and between two nucleons in the nuclear medium (dressed interaction).Because of the above reasons, specific nuclear many-body models have been devised of which each one sheds light on some selected aspects of nuclear structure. Only combining the viewpoints of different models, a global insight of the atomic nucleus can be gained. In this chapter, we revise the the Nuclear Shell Model as an example of the microscopic approach, and the Collective Model as an example of the geometric approach. Finally, we study the statistical properties of nuclear spectra, basing on symmetry principles, to find out whether there is quantum chaos in the atomic nucleus. All three major approaches have been rewarded with the Nobel Prize of Physics. In the text, we will stress how each approach introduces its own series of approximations to reduce the prohibitingly large number of degrees of freedom of the full many-body problem to a smaller manageable number of effective degrees of freedom.

  18. Nuclear pursuits

    SciTech Connect

    Not Available

    1993-05-01

    This table lists quantities of warheads (in stockpile, peak number per year, total number built, number of known test explosions), weapon development milestones (developers of the atomic bomb and hydrogen bomb, date of first operational ICBM, first nuclear-powered naval SSN in service, first MIRVed missile deployed), and testing milestones (first fission test, type of boosted fission weapon, multistage thermonuclear test, number of months from fission bomb to multistage thermonuclear bomb, etc.), and nuclear infrastructure (assembly plants, plutonium production reactors, uranium enrichment plants, etc.). Countries included in the tally are the United States, Soviet Union, Britain, France, and China.

  19. Space Telescope moving target tracking

    NASA Technical Reports Server (NTRS)

    Strikwerda, T. E.; Strohbehn, K.; Fowler, K. R.; Skillman, D. R.

    1985-01-01

    This paper formulates a Space Telescope (ST) moving target tracking algorithm and evaluates a practical implementation. The algorithm is shown to be satisfactory for tracking such moving objects as the moons of Mars.

  20. Remote sensing of water tracks

    NASA Astrophysics Data System (ADS)

    Trochim, E. D.; Prakash, A.; Kane, D. L.; Romanovsky, V. E.

    2016-03-01

    Water tracks are an intrinsic part of the surficial drainage network in the foothills of the Brooks Range, Alaska. They preferentially transport water off hillslopes and represent the interplay between hydrology, vegetation, geomorphology, and permafrost characteristics. This research on mapping the location of water tracks builds on previous work which demonstrated that different types of water tracks exist due to difference primarily driven by geomorphology. We used a combination method where spectral classifications, texture, and topography were fed into random forests to identify the water track classes. The most accurate distributions were obtained for the organic-rich and wide water track classes. The distinct linear shapes of the water tracks could also be visualized for many of the classes, especially in areas where the water tracks were particularly discrete. The biggest challenges to mapping the water tracks were due to class imbalances and high variability within and overlapping between classes. This research presents a significant step forward in understanding periglacial landscape dynamics.

  1. A Unique Master's Program in Combined Nuclear Technology and Nuclear Chemistry at Chalmers University of Technology, Sweden

    NASA Astrophysics Data System (ADS)

    Skarnemark, Gunnar; Allard, Stefan; Ekberg, Christian; Nordlund, Anders

    2009-08-01

    The need for engineers and scientists who can ensure safe and secure use of nuclear energy is large in Sweden and internationally. Chalmers University of Technology is therefore launching a new 2-year master's program in Nuclear Engineering, with start from the autumn of 2009. The program is open to Swedish and foreign students. The program starts with compulsory courses dealing with the basics of nuclear chemistry and physics, radiation protection, nuclear power and reactors, nuclear fuel supply, nuclear waste management and nuclear safety and security. There are also compulsory courses in nuclear industry applications and sustainable energy futures. The subsequent elective courses can be chosen freely but there is also a possibility to choose informal tracks that concentrate on nuclear chemistry or reactor technology and physics. The nuclear chemistry track comprises courses in e.g. chemistry of lanthanides, actinides and transactinides, solvent extraction, radioecology and radioanalytical chemistry and radiopharmaceuticals. The program is finished with a one semester thesis project. This is probably a unique master program in the sense of its combination of deep courses in both nuclear technology and nuclear chemistry.

  2. A Unique Master's Program in Combined Nuclear Technology and Nuclear Chemistry at Chalmers University of Technology, Sweden

    SciTech Connect

    Skarnemark, Gunnar; Allard, Stefan; Ekberg, Christian; Nordlund, Anders

    2009-08-19

    The need for engineers and scientists who can ensure safe and secure use of nuclear energy is large in Sweden and internationally. Chalmers University of Technology is therefore launching a new 2-year master's program in Nuclear Engineering, with start from the autumn of 2009. The program is open to Swedish and foreign students. The program starts with compulsory courses dealing with the basics of nuclear chemistry and physics, radiation protection, nuclear power and reactors, nuclear fuel supply, nuclear waste management and nuclear safety and security. There are also compulsory courses in nuclear industry applications and sustainable energy futures. The subsequent elective courses can be chosen freely but there is also a possibility to choose informal tracks that concentrate on nuclear chemistry or reactor technology and physics. The nuclear chemistry track comprises courses in e.g. chemistry of lanthanides, actinides and transactinides, solvent extraction, radioecology and radioanalytical chemistry and radiopharmaceuticals. The program is finished with a one semester thesis project. This is probably a unique master program in the sense of its combination of deep courses in both nuclear technology and nuclear chemistry.

  3. Improvement in the speed of alpha-decay track measurement

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hidetaka; Nakazawa, Kazuma; Yoshida, Jyunya; Mishina, Akihiro; Kinbara, Shinji; Endo, Yoko; Itoh, Hiroki; Soe, Mintkyaw; Tantint, Kint; E07 Collaboration

    2014-09-01

    For analysis of double- Λ hypernucleus in nuclear emulsion, it is necessary to know shrinkage factor and density of emulsion plate by measuring the track ranges of alpha particles. The kinetic energies of nuclear fragment from double- Λ hypernucleus are measured by their ranges in the emulsion, which is dedicated photographic emulsion for nuclear physics. Then we have to reconstruct their original ranges since the emulsion plate shrinks about half in thickness after development. Besides, we have to calibrate range-energy relation because the density depends on the emulsion content of moisture. Therefore we use alpha-rays with monochromatic energy as calibration sources which were emitted from natural Radioisotope such as Thorium series and Uranium series in the emulsion. Technique which performs alpha-tracks measurement by image processing is being studied. In the E07 experiment at J-PARC, quick analysis is required for about alpha tracks on about 100 double- Λ hypernuclear events within a few years. At present, we are developing automated range measurement technique instead of traditional manual measurement. Alpha tracks are seen as black, bold lines in micrographs. Image processing program detects such lines and the positions, angles, ranges of them in micrographs.

  4. Nuclear winter or nuclear fall?

    NASA Astrophysics Data System (ADS)

    Berger, André

    Climate is universal. If a major modern nuclear war (i.e., with a large number of small-yield weapons) were to happen, it is not even necessary to have a specific part of the world directly involved for there to be cause to worry about the consequences for its inhabitants and their future. Indeed, smoke from fires ignited by the nuclear explosions would be transported by winds all over the world, causing dark and cold. According to the first study, by Turco et al. [1983], air surface temperature over continental areas of the northern mid-latitudes (assumed to be the nuclear war theatre) would fall to winter levels even in summer (hence the term “nuclear winter”) and induce drastic climatic conditions for several months at least. The devastating effects of a nuclear war would thus last much longer than was assumed initially. Discussing to what extent these estimations of long-term impacts on climate are reliable is the purpose of this article.

  5. Perceptual style and tracking performance

    NASA Technical Reports Server (NTRS)

    Atchley, Paul

    1991-01-01

    The relationship between perceptual style and tracking of a target was examined. Four pilots were given the Embedded Figures Test to assess their degrees of field dependence or independence. Then they flew in a helicopter simulator and attempted to track an airborne target. A high negative correlation was found between perceptual style and tracking performance. Field-independent subjects were able to track the target for longer periods than field-dependent subjects.

  6. Perceptual style and tracking performance

    NASA Technical Reports Server (NTRS)

    Atchley, Paul

    1991-01-01

    The relationship between perceptual style and tracking of a target was examined. Four pilots were given the Embedded Figures Test to assess their degrees of field dependence or independence. Then they flew in a helicopter simulator and attempted to track an airborne target. A high negative correlation was found between perceptual style and tracking performance. Field-independent subjects were able to track the target for longer periods than field-dependent subjects.

  7. Satellite (IRLS) tracking of elk

    NASA Technical Reports Server (NTRS)

    Buechner, H. K.

    1972-01-01

    The practicability of tracking free roaming animals in natural environments by satellite systems is reported. Satellite systems combine continuous tracking with simultaneous monitoring of physiological and environmental parameters through a combination of radio tracking and biotelemetric ground systems that lead to a better understanding of animal behavior and migration patterns.

  8. Dinosaur Tracks and Traces

    NASA Astrophysics Data System (ADS)

    Gillette, David D.; Lockley, Martin G.

    1991-02-01

    The study of fossilized dinosaur remains, vertebrate paleontology is a well established discipline, but the discovery and rediscovery of numerous and varied dinosaur footprints and nest sites has spurred a renaissance in the associated field of ichnological research. Dinosaur Tracks and Traces is the first book ever to be devoted to this subject, and it represents the work of seventy noted dinosaur ichnologists. Contributors address the history of science and the relevance of dinosaur ichnology to the interpretation of dinosaur behaviour, paleoecology, paleoenvironments, and evolution. Several new preservation, conservation, and documentation techniques are also presented. The book is richly illustrated and is intended for students and professionals in the areas of paleontology, vertebrate zoology, geology, and paleoenvironmental analysis. The historical aspects of the book and the many site descriptions also make Dinosaur Tracks and Traces appealing to amateur fossil collectors and dinosaur enthusiasts.

  9. Longwall shearer tracking system

    NASA Technical Reports Server (NTRS)

    Poulsen, P. D. (Inventor); Stein, R. J.; Pease, R. E.

    1984-01-01

    A tracking system for measuring and recording the movements of a longwall shearer vehicle includes an optical tracking assembly carried at one end of a desired vehicle path and a retroreflector assembly carried by the vehicle. Continuous horizontal and vertical light beams are alternately transmitted by means of a rotating Dove prism to the reflector assembly. A vertically reciprocating reflector interrupts the continuous light beams and converts these to discrete horizontal and vertical light beam images transmitted at spaced intervals along the path. A second rotating Dove prism rotates the vertical images to convert them to a second series of horizontal images while the first mentioned horizontal images are left unrotated and horizontal. The images are recorded on a film.

  10. Tracking optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Ferguson, R. Daniel; Hammer, Daniel X.; Paunescu, Lelia Adelina; Beaton, Siobahn; Schuman, Joel S.

    2004-09-01

    An experimental tracking optical coherence tomography (OCT) system has been clinically tested. The prototype instrument uses a secondary sensing beam and steering mirrors to compensate for eye motion with a closed-loop bandwidth of 1 kHz and tracking accuracy, to within less than the OCT beam diameter. The retinal tracker improved image registration accuracy to <1 transverse pixel (<60 µm). Composite OCT images averaged over multiple scans and visits show a sharp fine structure limited only by transverse pixel size. As the resolution of clinical OCT systems improves, the capability to reproducibly map complex structures in the living eye at high resolution will lead to improved understanding of disease processes and improved sensitivity and specificity of diagnostic procedures.

  11. On particle track detectors

    NASA Technical Reports Server (NTRS)

    Benton, E. V.; Gruhn, T. A.; Andrus, C. H.

    1973-01-01

    Aqueous sodium hydroxide is widely used to develop charged particle tracks in polycarbonate film, particularly Lexan. The chemical nature of the etching process for this system has been determined. A method employing ultra-violet absorbance was developed for monitoring the concentration of the etch products in solution. Using this method it was possible to study the formation of the etching solution saturated in etch products. It was found that the system super-saturates to a significant extent before precipitation occurs. It was also learned that the system approaches its equilibrium state rather slowly. It is felt that both these phenomena may be due to the presence of surfactant in the solution. In light of these findings, suggestions are given regarding the preparation and maintenance of the saturated etch solution. Two additional research projects, involving automated techniques for particle track analysis and particle identification using AgCl crystals, are briefly summarized.

  12. Motion Tracking System

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Integrated Sensors, Inc. (ISI), under NASA contract, developed a sensor system for controlling robot vehicles. This technology would enable a robot supply vehicle to automatically dock with Earth-orbiting satellites or the International Space Station. During the docking phase the ISI-developed sensor must sense the satellite's relative motion, then spin so the robot vehicle can adjust its motion to align with the satellite and slowly close until docking is completed. ISI used the sensing/tracking technology as the basis of its OPAD system, which simultaneously tracks an object's movement in six degrees of freedom. Applications include human limb motion analysis, assembly line position analysis and auto crash dummy motion analysis. The NASA technology is also the basis for Motion Analysis Workstation software, a package to simplify the video motion analysis process.

  13. Tracking change over time

    USGS Publications Warehouse

    ,

    2011-01-01

    Landsat satellites capture images of Earth from space-and have since 1972! These images provide a long-term record of natural and human-induced changes on the global landscape. Comparing images from multiple years reveals slow and subtle changes as well as rapid and devastating ones. Landsat images are available over the Internet at no charge. Using the free software MultiSpec, students can track changes to the landscape over time-just like remote sensing scientists do! The objective of the Tracking Change Over Time lesson plan is to get students excited about studying the changing Earth. Intended for students in grades 5-8, the lesson plan is flexible and may be used as a student self-guided tutorial or as a teacher-led class lesson. Enhance students' learning of geography, map reading, earth science, and problem solving by seeing landscape changes from space.

  14. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are…

  15. Nuclear Terrorism.

    SciTech Connect

    Hecker, Siegfried S.

    2001-01-01

    As pointed out by several speakers, the level of violence and destruction in terrorist attacks has increased significantly during the past decade. Fortunately, few have involved weapons of mass destruction, and none have achieved mass casualties. The Aum Shinrikyo release of lethal nerve agent, sarin, in the Tokyo subway on March 20, 1995 clearly broke new ground by crossing the threshold in attempting mass casualties with chemical weapons. However, of all weapons of mass destruction, nuclear weapons still represent the most frightening threat to humankind. Nuclear weapons possess an enormous destructive force. The immediacy and scale of destruction are unmatched. In addition to destruction, terrorism also aims to create fear among the public and governments. Here also, nuclear weapons are unmatched. The public's fear of nuclear weapons or, for that matter, of all radioactivity is intense. To some extent, this fear arises from a sense of unlimited vulnerability. That is, radioactivity is seen as unbounded in three dimensions - distance, it is viewed as having unlimited reach; quantity, it is viewed as having deadly consequences in the smallest doses (the public is often told - incorrectly, of course - that one atom of plutonium will kill); and time, if it does not kill you immediately, then it will cause cancer decades hence.

  16. Nuclear medicine

    SciTech Connect

    Wagner, H.N. Jr.

    1986-10-17

    In 1985 and 1986 nuclear medicine became more and more oriented toward in vov chemistry, chiefly as a result of advances in positron emission tomography (PET). The most important trend was the extension of PET technology into the care of patients with brain tumors, epilepsy, and heart disease. A second trend was the increasing use of single-photon emission computed tomography (SPECT).

  17. Nuclear Misinformation

    ERIC Educational Resources Information Center

    Ford, Daniel F.; Kendall, Henry W.

    1975-01-01

    Many scientists feel that research into nuclear safety has been diverted or distorted, and the results of the research concealed or inaccurately reported on a large number of occasions. Of particular concern have been the emergency cooling systems which have not, as yet, been adequately tested. (Author/MA)

  18. Nuclear Science.

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Education, Harrisburg. Bureau of Curriculum Services.

    This document is a report on a course in nuclear science for the high school curriculum. The course is designed to provide a basic but comprehensive understanding of the atom in the light of modern knowledge, and to show how people attempt to harness the tremendous energy liberated through fission and fusion reactions. The course crosses what are…

  19. Nuclear orbiting

    SciTech Connect

    Shapira, D.

    1988-01-01

    Nuclear orbiting following collisions between sd and p shell nuclei is discussed. The dependence of this process on the real and imaginary parts of the nucleus-nucleus potential is discussed, as well as the evolution of the dinucleus toward a fully equilibrated fused system. 26 refs., 15 figs.

  20. Nuclear Misinformation

    ERIC Educational Resources Information Center

    Ford, Daniel F.; Kendall, Henry W.

    1975-01-01

    Many scientists feel that research into nuclear safety has been diverted or distorted, and the results of the research concealed or inaccurately reported on a large number of occasions. Of particular concern have been the emergency cooling systems which have not, as yet, been adequately tested. (Author/MA)

  1. Nuclear energy.

    PubMed

    Wilson, Peter D

    2010-01-01

    The technical principles and practices of the civil nuclear industry are described with particular reference to fission and its products, natural and artificial radioactivity elements principally concerned and their relationships, main types of reactor, safety issues, the fuel cycle, waste management, issues related to weapon proliferation, environmental considerations and possible future developments.

  2. NUCLEAR REACTOR

    DOEpatents

    Treshow, M.

    1961-09-01

    A boiling-water nuclear reactor is described wherein control is effected by varying the moderator-to-fuel ratio in the reactor core. This is accomplished by providing control tubes containing a liquid control moderator in the reactor core and providing means for varying the amount of control moderatcr within the control tubes.

  3. Hazardous chemical tracking system (HAZ-TRAC)

    SciTech Connect

    Bramlette, J D; Ewart, S M; Jones, C E

    1990-07-01

    Westinghouse Idaho Nuclear Company, Inc. (WINCO) developed and implemented a computerized hazardous chemical tracking system, referred to as Haz-Trac, for use at the Idaho Chemical Processing Plant (ICPP). Haz-Trac is designed to provide a means to improve the accuracy and reliability of chemical information, which enhances the overall quality and safety of ICPP operations. The system tracks all chemicals and chemical components from the time they enter the ICPP until the chemical changes form, is used, or becomes a waste. The system runs on a Hewlett-Packard (HP) 3000 Series 70 computer. The system is written in COBOL and uses VIEW/3000, TurboIMAGE/DBMS 3000, OMNIDEX, and SPEEDWARE. The HP 3000 may be accessed throughout the ICPP, and from remote locations, using data communication lines. Haz-Trac went into production in October, 1989. Currently, over 1910 chemicals and chemical components are tracked on the system. More than 2500 personnel hours were saved during the first six months of operation. Cost savings have been realized by reducing the time needed to collect and compile reporting information, identifying and disposing of unneeded chemicals, and eliminating duplicate inventories. Haz-Trac maintains information required by the Superfund Amendment Reauthorization Act (SARA), the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and the Occupational Safety and Health Administration (OSHA).

  4. Nuclear eclectic power.

    PubMed

    Rose, D J

    1974-04-19

    The uranium and thorium resources, the technology, and the social impacts all seem to presage an even sharper increase in nuclear power for electric generation than had hitherto been predicted. There are more future consequences. The "hydrogen economy." Nuclear power plants operate best at constant power and full load. Thus, a largely nuclear electric economy has the problem of utilizing substantial off-peak capacity; the additional energy generation can typically be half the normal daily demand. Thus, the option of generating hydrogen as a nonpolluting fuel receives two boosts: excess nuclear capacity to produce it, plus much higher future costs for oil and natural gas. However, the so-called "hydrogen economy" must await the excess capacity, which will not occur until the end of the century. Nonelectric uses. By analyses similar to those performed here, raw nuclear heat can be shown to be cheaper than heat from many other fuel sources, especially nonpolluting ones. This will be particularly true as domestic natural gas supplies become more scarce. Nuclear heat becomes attractive for industrial purposes, and even for urban district heating, provided (i) the temperature is high enough (this is no problem for district heating, but could be for industry; the HTGR's and breeders, with 600 degrees C or more available, have the advantage); (ii) there is a market for large quantities (a heat rate of 3800 Mw thermal, the reactor size permitted today, will heat Boston, with some to spare); and (iii) the social costs become more definitely resolved in favor of nuclear power. Capital requirements. Nuclear-electric installations are very capital-intensive. One trillion dollars for the plants, backup industry, and so forth is only 2 percent of the total gross national product (GNP) between 1974 and 2000, at a growth rate of 4 percent per year. But capital accumulation tends to run at about 10 percent of the GNP, so the nuclear requirements make a sizable perturbation. Also

  5. Fast tracking hospital construction.

    PubMed

    Quirk, Andrew

    2013-03-01

    Hospital leaders should consider four factors in determining whether to fast track a hospital construction project: Expectations of project length, quality, and cost. Whether decisions can be made quickly as issues arise. Their own time commitment to the project, as well as that of architects, engineers, construction managers, and others. The extent to which they are willing to share with the design and construction teams how and why decisions are being made.

  6. SOFIA tracking image simulation

    NASA Astrophysics Data System (ADS)

    Taylor, Charles R.; Gross, Michael A. K.

    2016-09-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) tracking camera simulator is a component of the Telescope Assembly Simulator (TASim). TASim is a software simulation of the telescope optics, mounting, and control software. Currently in its fifth major version, TASim is relied upon for telescope operator training, mission planning and rehearsal, and mission control and science instrument software development and testing. TASim has recently been extended for hardware-in-the-loop operation in support of telescope and camera hardware development and control and tracking software improvements. All three SOFIA optical tracking cameras are simulated, including the Focal Plane Imager (FPI), which has recently been upgraded to the status of a science instrument that can be used on its own or in parallel with one of the seven infrared science instruments. The simulation includes tracking camera image simulation of starfields based on the UCAC4 catalog at real-time rates of 4-20 frames per second. For its role in training and planning, it is important for the tracker image simulation to provide images with a realistic appearance and response to changes in operating parameters. For its role in tracker software improvements, it is vital to have realistic signal and noise levels and precise star positions. The design of the software simulation for precise subpixel starfield rendering (including radial distortion), realistic point-spread function as a function of focus, tilt, and collimation, and streaking due to telescope motion will be described. The calibration of the simulation for light sensitivity, dark and bias signal, and noise will also be presented

  7. Uncorrelated Track Avoidance

    DTIC Science & Technology

    2008-03-01

    continual series of uncorrelated tracks when gathering observations. The constants of the motion for simple two-body motion for a satellite orbiting the Earth ...of the Earth -Centered Rotating System, Ẑ-component of inertial angular momentum (Hk), and the time rate of change of the right ascension of the...3 2.1 Earth -Centered Coordinate Frames . . . . . . . . . . . . . . . . . . . 3 III. Integrals of Satellite Motion

  8. PARTICLE BEAM TRACKING CIRCUIT

    DOEpatents

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  9. Tracking Online Trails

    NASA Astrophysics Data System (ADS)

    Qi, Man; Edgar-Nevill, Denis; Wang, Yongquan; Xu, Rongsheng

    Traceability is a key to the investigation of the internet criminal and a cornerstone of internet research. It is impossible to prevent all internet misuse but may be possible to identify and trace the users, and then take appropriate action. This paper presents the value of traceability within the email/-newsposting utilities, the technologies being using to hide identities, the difficulties in locating the traceable data and the challenges in tracking online trails.

  10. Note: Fast neutron efficiency in CR-39 nuclear track detectors

    SciTech Connect

    Cavallaro, S.

    2015-03-15

    CR-39 samples are commonly employed for fast neutron detection in fusion reactors and in inertial confinement fusion experiments. The literature reported efficiencies are strongly depending on experimental conditions and, in some cases, highly dispersed. The present note analyses the dependence of efficiency as a function of various parameters and experimental conditions in both the radiator-assisted and the stand-alone CR-39 configurations. Comparisons of literature experimental data with Monte Carlo calculations and optimized efficiency values are shown and discussed.

  11. Fast Track Study

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The NASA Fast Track Study supports the efforts of a Special Study Group (SSG) made up of members of the Advanced Project Management Class number 23 (APM-23) that met at the Wallops Island Management Education Center from April 28 - May 8, 1996. Members of the Class expressed interest to Mr. Vem Weyers in having an input to the NASA Policy Document (NPD) 7120.4, that will replace NASA Management Institute (NMI) 7120.4, and the NASA Program/Project Management Guide. The APM-23 SSG was tasked with assisting in development of NASA policy on managing Fast Track Projects, defined as small projects under $150 million and completed within three years. 'Me approach of the APM-23 SSG was to gather data on successful projects working in a 'Better, Faster, Cheaper' environment, within and outside of NASA and develop the Fast Track Project section of the NASA Program/Project Management Guide. Fourteen interviews and four other data gathering efforts were conducted by the SSG, and 16 were conducted by Strategic Resources, Inc. (SRI), including five interviews at the Jet Propulsion Laboratory (JPL) and one at the Applied Physics Laboratory (APL). The interviews were compiled and analyzed for techniques and approaches commonly used to meet severe cost and schedule constraints.

  12. Energy Tracking Diagrams

    NASA Astrophysics Data System (ADS)

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-02-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the Next Generation Science Standards, the primary conceptual learning goal is for learners to conserve energy as they track the transfers and transformations of energy within, into, or out of the system of interest in complex physical processes. As part of tracking energy transfers among objects, learners should (i) distinguish energy from matter, including recognizing that energy flow does not uniformly align with the movement of matter, and should (ii) identify specific mechanisms by which energy is transferred among objects, such as mechanical work and thermal conduction. As part of tracking energy transformations within objects, learners should (iii) associate specific forms with specific models and indicators (e.g., kinetic energy with speed and/or coordinated motion of molecules, thermal energy with random molecular motion and/or temperature) and (iv) identify specific mechanisms by which energy is converted from one form to another, such as incandescence and metabolism. Eventually, we may hope for learners to be able to optimize systems to maximize some energy transfers and transformations and minimize others, subject to constraints based in both imputed mechanism (e.g., objects must have motion energy in order for gravitational energy to change) and the second law of thermodynamics (e.g., heating is irreversible). We hypothesize that a subsequent goal of energy learning—innovating to meet socially relevant needs—depends crucially on the extent to which these goals have been met.

  13. Respiration tracking in radiosurgery

    SciTech Connect

    Schweikard, Achim; Shiomi, Hiroya; Adler, John

    2004-10-01

    Respiratory motion is difficult to compensate for with conventional radiotherapy systems. An accurate tracking method for following the motion of the tumor is of considerable clinical relevance. We investigate methods to compensate for respiratory motion using robotic radiosurgery. In this system the therapeutic beam is moved by a robotic arm, and follows the moving target through a combination of infrared tracking and synchronized x-ray imaging. Infrared emitters are used to record the motion of the patient's skin surface. The position of internal gold fiducials is computed repeatedly during treatment, via x-ray image processing. We correlate the motion between external and internal markers. From this correlation model we infer the placement of the internal target during time intervals where no x-ray images are taken. Fifteen patients with lung tumors have recently been treated with a fully integrated system implementing this new method. The clinical trials confirm our hypothesis that internal motion and external motion are indeed correlated. In a preliminar study we have extended our work to tracking without implanted fiducials, based on algorithms for computing deformation motions and digitally reconstructed radiographs.

  14. Cellular track model for study of heavy ion beams

    NASA Technical Reports Server (NTRS)

    Shinn, Judy L.; Katz, Robert; Cucinotta, Francis A.; Wilson, John W.; Ngo, Duc M.

    1993-01-01

    Track theory is combined with a realistic model of a heavy ion beam to study the effects of nuclear fragmentation on cell survival and biological effectiveness. The effects of secondary reaction products are studied as a function of depth in a water column. Good agreement is found with experimental results for the survival of human T-l cells exposed to monoenergetic carbon, neon, and argon beams under aerobic and hypoxia conditions. The present calculation, which includes the effect of target fragmentation, is a significant improvement over an earlier calculation because of the use of a vastly improved beam model with no change in the track theory or cellular response parameters.

  15. GEM tracking system of the BM@N experiment

    NASA Astrophysics Data System (ADS)

    Baranov, D.; Bazylev, S.; Kapishin, M.; Kapusniak, K.; Karjavine, V.; Khabarov, S.; Kolesnikov, A.; Kulish, E.; Lenivenko, V.; Makankin, A.; Maksymchuk, A.; Mehl, B.; De Oliveira, R.; Palchik, V.; Rodriguez, A.; Rufanov, I.; Shutov, A.; Slepnev, I.; Slepnev, V.; Vasiliev, S.

    2017-06-01

    BM@N (Baryonic Matter at the Nuclotron) is the fixed target experiment aimed to study nuclear matter in the relativistic heavy ion collisions at the Nuclotron accelerator in JINR. Detectors based on Gas Electron multipliers (GEM) have been identified as appropriate for the BM@N tracking system, which is located inside the BM@N analyzing magnet. The structure of the GEM detectors and the results of study of their characteristics are presented. The GEM detectors are integrated into the BM@N experimental setup and data acquisition system. The performance of the GEM tracking system in the first technical run with the deuteron beam is shortly reviewed.

  16. Fuzzy Logic Particle Tracking

    NASA Technical Reports Server (NTRS)

    2005-01-01

    A new all-electronic Particle Image Velocimetry technique that can efficiently map high speed gas flows has been developed in-house at the NASA Lewis Research Center. Particle Image Velocimetry is an optical technique for measuring the instantaneous two component velocity field across a planar region of a seeded flow field. A pulsed laser light sheet is used to illuminate the seed particles entrained in the flow field at two instances in time. One or more charged coupled device (CCD) cameras can be used to record the instantaneous positions of particles. Using the time between light sheet pulses and determining either the individual particle displacements or the average displacement of particles over a small subregion of the recorded image enables the calculation of the fluid velocity. Fuzzy logic minimizes the required operator intervention in identifying particles and computing velocity. Using two cameras that have the same view of the illumination plane yields two single exposure image frames. Two competing techniques that yield unambiguous velocity vector direction information have been widely used for reducing the single-exposure, multiple image frame data: (1) cross-correlation and (2) particle tracking. Correlation techniques yield averaged velocity estimates over subregions of the flow, whereas particle tracking techniques give individual particle velocity estimates. For the correlation technique, the correlation peak corresponding to the average displacement of particles across the subregion must be identified. Noise on the images and particle dropout result in misidentification of the true correlation peak. The subsequent velocity vector maps contain spurious vectors where the displacement peaks have been improperly identified. Typically these spurious vectors are replaced by a weighted average of the neighboring vectors, thereby decreasing the independence of the measurements. In this work, fuzzy logic techniques are used to determine the true

  17. Engineering cell-fluorescent ion track hybrid detectors

    PubMed Central

    2013-01-01

    Background The lack of sensitive biocompatible particle track detectors has so far limited parallel detection of physical energy deposition and biological response. Fluorescent nuclear track detectors (FNTDs) based on Al2O3:C,Mg single crystals combined with confocal laser scanning microscopy (CLSM) provide 3D information on ion tracks with a resolution limited by light diffraction. Here we report the development of next generation cell-fluorescent ion track hybrid detectors (Cell-Fit-HD). Methods The biocompatibility of FNTDs was tested using six different cell lines, i.e. human non-small cell lung carcinoma (A549), glioblastoma (U87), androgen independent prostate cancer (PC3), epidermoid cancer (A431) and murine (VmDk) glioma SMA-560. To evaluate cell adherence, viability and conformal coverage of the crystals different seeding densities and alternative coating with extracellular matrix (fibronectin) was tested. Carbon irradiation was performed in Bragg peak (initial 270.55 MeV u−1). A series of cell compartment specific fluorescence stains including nuclear (HOECHST), membrane (Glut-1), cytoplasm (Calcein AM, CM-DiI) were tested on Cell-Fit-HDs and a single CLSM was employed to co-detect the physical (crystal) as well as the biological (cell layer) information. Results The FNTD provides a biocompatible surface. Among the cells tested, A549 cells formed the most uniform, viable, tightly packed epithelial like monolayer. The ion track information was not compromised in Cell-Fit-HD as compared to the FNTD alone. Neither cell coating and culturing, nor additional staining procedures affected the properties of the FNTD surface to detect ion tracks. Standard immunofluorescence and live staining procedures could be employed to co-register cell biology and ion track information. Conclusions The Cell-Fit-Hybrid Detector system is a promising platform for a multitude of studies linking biological response to energy deposition at high level of optical microscopy

  18. Feature-aided tracking (FAT)

    NASA Astrophysics Data System (ADS)

    Singer, Paul F.; Coursey, Amanda L.

    2004-08-01

    Association of observations and tracks is a fundamental component of most solutions to the tracking problem. Association is frequently formulated as a multiple hypothesis test. Typically, the test statistic, called the track score, is the likelihood or likelihood ratio of the observations conditioned upon the association hypotheses. Assuming that the test is reasonably efficient, further reduction in the association error probability necessitates the introduction of additional information into the track score. This additional information is embodied in quantities called track features which are to be included in the track score. In practice, the necessary conditional probabilities of the track features are unknown. The class of non-parametric hypothesis tests is designed to provide such a test in the absence of any probabilistic information about the data. However, the test statistics used in non-parametric tests cannot be used directly in the track score. The one probabilistic quantity generally available with non-parametric tests is the Type I error probability, the probability of failing to accept a true hypothesis. If the non-parametric test is distribution free then the Type I error probability is independent of the distribution of the track features. This paper presents a distribution free, non-parametric test of the track features that can be used to test the association hypotheses and a quantity that can be included in the track score is derived from the Type I error probability of the test.

  19. Thermal tracking of sports players.

    PubMed

    Gade, Rikke; Moeslund, Thomas B

    2014-07-29

    We present here a real-time tracking algorithm for thermal video from a sports game. Robust detection of people includes routines for handling occlusions and noise before tracking each detected person with a Kalman filter. This online tracking algorithm is compared with a state-of-the-art offline multi-target tracking algorithm. Experiments are performed on a manually annotated 2-minutes video sequence of a real soccer game. The Kalman filter shows a very promising result on this rather challenging sequence with a tracking accuracy above 70% and is superior compared with the offline tracking approach. Furthermore, the combined detection and tracking algorithm runs in real time at 33 fps, even with large image sizes of 1920 × 480 pixels.

  20. Thermal Tracking of Sports Players

    PubMed Central

    Gade, Rikke; Moeslund, Thomas B.

    2014-01-01

    We present here a real-time tracking algorithm for thermal video from a sports game. Robust detection of people includes routines for handling occlusions and noise before tracking each detected person with a Kalman filter. This online tracking algorithm is compared with a state-of-the-art offline multi-target tracking algorithm. Experiments are performed on a manually annotated 2-minutes video sequence of a real soccer game. The Kalman filter shows a very promising result on this rather challenging sequence with a tracking accuracy above 70% and is superior compared with the offline tracking approach. Furthermore, the combined detection and tracking algorithm runs in real time at 33 fps, even with large image sizes of 1920 × 480 pixels. PMID:25076219

  1. PHOTOGRAPHIC TRACKING FOR HIGH ALTITUDE SATELLITES,

    DTIC Science & Technology

    TRACKING, *COMMUNICATION SATELLITES, ARTIFICIAL SATELLITES, TRACKING CAMERAS, COMMUNICATION SATELLITES, PHOTOGRAPHY, SATELLITE ATTITUDE, ORBITS, ERRORS, CORRECTIONS, HIGH ALTITUDE , ILLUMINATION, STARS.

  2. An interface tracking model for droplet electrocoalescence.

    SciTech Connect

    Erickson, Lindsay Crowl

    2013-09-01

    This report describes an Early Career Laboratory Directed Research and Development (LDRD) project to develop an interface tracking model for droplet electrocoalescence. Many fluid-based technologies rely on electrical fields to control the motion of droplets, e.g. microfluidic devices for high-speed droplet sorting, solution separation for chemical detectors, and purification of biodiesel fuel. Precise control over droplets is crucial to these applications. However, electric fields can induce complex and unpredictable fluid dynamics. Recent experiments (Ristenpart et al. 2009) have demonstrated that oppositely charged droplets bounce rather than coalesce in the presence of strong electric fields. A transient aqueous bridge forms between approaching drops prior to pinch-off. This observation applies to many types of fluids, but neither theory nor experiments have been able to offer a satisfactory explanation. Analytic hydrodynamic approximations for interfaces become invalid near coalescence, and therefore detailed numerical simulations are necessary. This is a computationally challenging problem that involves tracking a moving interface and solving complex multi-physics and multi-scale dynamics, which are beyond the capabilities of most state-of-the-art simulations. An interface-tracking model for electro-coalescence can provide a new perspective to a variety of applications in which interfacial physics are coupled with electrodynamics, including electro-osmosis, fabrication of microelectronics, fuel atomization, oil dehydration, nuclear waste reprocessing and solution separation for chemical detectors. We present a conformal decomposition finite element (CDFEM) interface-tracking method for the electrohydrodynamics of two-phase flow to demonstrate electro-coalescence. CDFEM is a sharp interface method that decomposes elements along fluid-fluid boundaries and uses a level set function to represent the interface.

  3. Latest Developments in Nuclear Emulsion Technology

    NASA Astrophysics Data System (ADS)

    Morishima, Kunihiro

    Nuclear emulsion is high sensitive photographic film used for detection of three-dimensional trajectory of charged particles. These trajectories are recorded as tracks consist of a lot of silver grains. The size of silver grain is about 1 μm, so that nuclear emulsion has submicron three-dimensional spatial resolution, which gives us a few mrad three-dimensional angular resolution. The important technical progress was speed-up of the read-out technique of nuclear emulsions built with optical microscope system. We succeeded in developing a high-speed three-dimensional read-out system named Super Ultra Track Selector (S-UTS) with the operating read-out speed of approximately 50 cm2/h. Nowadays we are developing the nuclear emulsion gel independently in Nagoya University by introducing emulsion gel production machine. Moreover, we are developing nuclear emulsion production technologies (gel production, poring and mass production). In this paper, development of nuclear emulsion technologies for the OPERA experiment, applications by the technologies and current development are described.

  4. Nuclear Medicine

    PubMed Central

    Streek, Penny Vande; Carretta, Robert; Weiland, Frederick L.

    1994-01-01

    The Council on Scientific Affairs of the California Medical Association presents the following epitomes of progress in nuclear medicine. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and clinical importance. The items are presented in simple epitome, and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, researchers, and scholars to stay abreast of progress in medicine, whether in their own field of special interest or another. The epitomes included here were selected by the Advisory Panel to the Section on Nuclear Medicine of the California Medical Association, and the summaries were prepared under the direction of Dr Lyons and the panel. PMID:7529452

  5. NUCLEAR REACTOR

    DOEpatents

    Anderson, C.R.

    1962-07-24

    A fluidized bed nuclear reactor and a method of operating such a reactor are described. In the design means are provided for flowing a liquid moderator upwardly through the center of a bed of pellets of a nentron-fissionable material at such a rate as to obtain particulate fluidization while constraining the lower pontion of the bed into a conical shape. A smooth circulation of particles rising in the center and falling at the outside of the bed is thereby established. (AEC)

  6. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashby, J.W.

    1958-09-16

    ABS>A graphite moderator structure is presented for a nuclear reactor compriscd of an assembly of similarly orientated prismatic graphite blocks arranged on spaced longitudinal axes lying in common planes wherein the planes of the walls of the blocks are positioned so as to be twisted reintive to the planes of said axes so thatthe unlmpeded dtrect paths in direction wholly across the walls of the blocks are limited to the width of the blocks plus spacing between the blocks.

  7. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-07-14

    High temperature reactors which are uniquely adapted to serve as the heat source for nuclear pcwered rockets are described. The reactor is comprised essentially of an outer tubular heat resistant casing which provides the main coolant passageway to and away from the reactor core within the casing and in which the working fluid is preferably hydrogen or helium gas which is permitted to vaporize from a liquid storage tank. The reactor core has a generally spherical shape formed entirely of an active material comprised of fissile material and a moderator material which serves as a diluent. The active material is fabricated as a gas permeable porous material and is interlaced in a random manner with very small inter-connecting bores or capillary tubes through which the coolant gas may flow. The entire reactor is divided into successive sections along the direction of the temperature gradient or coolant flow, each section utilizing materials of construction which are most advantageous from a nuclear standpoint and which at the same time can withstand the operating temperature of that particular zone. This design results in a nuclear reactor characterized simultaneously by a minimum critiral size and mass and by the ability to heat a working fluid to an extremely high temperature.

  8. Nuclear waste

    SciTech Connect

    Not Available

    1991-09-01

    Radioactive waste is mounting at U.S. nuclear power plants at a rate of more than 2,000 metric tons a year. Pursuant to statute and anticipating that a geologic repository would be available in 1998, the Department of Energy (DOE) entered into disposal contracts with nuclear utilities. Now, however, DOE does not expect the repository to be ready before 2010. For this reason, DOE does not want to develop a facility for monitored retrievable storage (MRS) by 1998. This book is concerned about how best to store the waste until a repository is available, congressional requesters asked GAO to review the alternatives of continued storage at utilities' reactor sites or transferring waste to an MRS facility, GAO assessed the likelihood of an MRSA facility operating by 1998, legal implications if DOE is not able to take delivery of wastes in 1998, propriety of using the Nuclear Waste Fund-from which DOE's waste program costs are paid-to pay utilities for on-site storage capacity added after 1998, ability of utilities to store their waste on-site until a repository is operating, and relative costs and safety of the two storage alternatives.

  9. Condensed Matter Nuclear Science

    NASA Astrophysics Data System (ADS)

    Biberian, Jean-Paul

    2006-02-01

    into characteristics of X-ray emission laser beams from solidstate cathode medium of high-current glow discharge / A. B. Karabut. Charged particles from Ti and Pd foils / L. Kowalski ... [et al.]. Cr-39 track detectors in cold fusion experiments: review and perspectives / A. S. Roussetski. Energetic particle shower in the vapor from electrolysis / R. A. Oriani and J. C. Fisher. Nuclear reactions produced in an operating electrolysis cell / R. A. Oriani and J. C. Fisher. Evidence of microscopic ball lightning in cold fusion experiments / E. H. Lewis. Neutron emission from D[symbol] gas in magnetic fields under low temperature / T. Mizuno ... [et al.]. Energetic charged particle emission from hydrogen-loaded Pd and Ti cathodes and its enhancement by He-4 implantation / A. G. Lipson ... [et al.]. H-D permeation. Observation of nuclear transmutation reactions induced by D[symbol] gas permeation through Pd complexes / Y. Iwamura ... [et al.]. Deuterium (hydrogen) flux permeating through palladium and condensed matter nuclear science / Q. M. Wei ... [et al.]. Triggering. Precursors and the fusion reactions in polarized Pd/D-D[symbol]O system: effect of an external electric field / S. Szpak, P. A. Mosier-Boss, and F. E. Gordon. Calorimetric and neutron diagnostics of liquids during laser irradiation / Yu. N. Bazhutov ... [et al.]. Anomalous neutron capture and plastic deformation of Cu and Pd cathodes during electrolysis in a weak thermalized neutron field: evidence of nuclei-lattice exchange / A. G. Lipson and G. H. Miley. H-D loading. An overview of experimental studies on H/Pd over-loading with thin Pd wires and different electrolytic solutions / A. Spallone ... [et al.] -- 3. Transmutations. Photon and particle emission, heat production, and surface transformation in Ni-H system / E. Campari ... [et al.]. Surface analysis of hydrogen-loaded nickel alloys / E. Campari ... [et al.]. Low-energy nuclear reactions and the leptonic monopole / G. Lochak and L. Urutskoev. Results

  10. Hierarchical fringe tracking

    NASA Astrophysics Data System (ADS)

    Petrov, Romain G.; Elhalkouj, Thami; Boskri, Abdelkarim; Folcher, Jean-Pierre; Lagarde, Stéphane; Bresson, Yves; Benkhaldoun, Zouhair; Lazrek, Mohamed; Rakshit, Suvendu

    2014-07-01

    The limiting magnitude is a key issue for optical interferometry. Pairwise fringe trackers based on the integrated optics concepts used for example in GRAVITY seem limited to about K=10.5 with the 8m Unit Telescopes of the VLTI, and there is a general "common sense" statement that the efficiency of fringe tracking, and hence the sensitivity of optical interferometry, must decrease as the number of apertures increases, at least in the near infrared where we are still limited by detector readout noise. Here we present a Hierarchical Fringe Tracking (HFT) concept with sensitivity at least equal to this of a two apertures fringe trackers. HFT is based of the combination of the apertures in pairs, then in pairs of pairs then in pairs of groups… The key HFT module is a device that behaves like a spatial filter for two telescopes (2TSF) and transmits all or most of the flux of a cophased pair in a single mode beam. We give an example of such an achromatic 2TSF, based on very broadband dispersed fringes analyzed by grids, and show that it allows piston measures from very broadband fringes with only 3 to 5 pixels per fringe tracker. We show the results of numerical simulation indicating that our device is a good achromatic spatial filter and allowing a first evaluation of its coupling efficiency, which is similar to this of a single mode fiber on a single aperture. Our very preliminary results indicate that HFT has a good chance to be a serious candidate for the most sensitive fringe tracking with the VLTI and also interferometers with much larger number of apertures. On the VLTI the first rough estimate of the magnitude gain with regard to the GRAVITY internal FT is between 2.5 and 3.5 magnitudes in K, with a decisive impact on the VLTI science program for AGNs, Young stars and planet forming disks.

  11. Tracking a Superstorm

    NASA Image and Video Library

    2017-09-27

    Oct. 29, 2012 – A day before landfall, Sandy intensified into a Category 2 superstorm nearly 1,000 miles wide. Credit: NASA's Goddard Space Flight Center and NASA Center for Climate Simulation Video and images courtesy of NASA/GSFC/William Putman -- A NASA computer model simulates the astonishing track and forceful winds of Hurricane Sandy. Hurricane Sandy pummeled the East Coast late in 2012’s Atlantic hurricane season, causing 159 deaths and $70 billion in damages. Days before landfall, forecasts of its trajectory were still being made. Some computer models showed that a trough in the jet stream would kick the monster storm away from land and out to sea. Among the earliest to predict its true course was NASA’s GEOS-5 global atmosphere model. The model works by dividing Earth’s atmosphere into a virtual grid of stacked boxes. A supercomputer then solves mathematical equations inside each box to create a weather forecast predicting Sandy’s structure, path and other traits. The NASA model not only produced an accurate track of Sandy, but also captured fine-scale details of the storm’s changing intensity and winds. Watch the video to see it for yourself. For more information, please visit: gmao.gsfc.nasa.gov/research/atmosphericassim/tracking_hur... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  12. QualiTrack: Highspeed TUI Tracking for Tabletop Applications

    NASA Astrophysics Data System (ADS)

    Hofer, Ramon; Nescher, Thomas; Kunz, Andreas

    In this paper, we present a new technology to track multiple active Tangible User Interfaces (TUI) on a projection table. We use a commercial high speed infrared tracking camera with modified firmware. With a special tracking method, we reach update rates of up to 250 Hz with low latencies. At this tracking rate, we are able to track the position, state and the orientation of more than 10 active TUIs on the table. For this, we use specified bit codes which are transmitted by the devices. We developed dedicated hardware (SyncUnit) and software to keep the devices and the high speed camera synchronized. The system of camera, SyncUnit, and devices is fully hardware controlled and delivers event coded tracking data for further usage in interactive applications.

  13. A computer system to analyze showers in nuclear emulsions: Center Director's discretionary fund report

    NASA Technical Reports Server (NTRS)

    Meegan, C. A.; Fountain, W. F.; Berry, F. A., Jr.

    1987-01-01

    A system to rapidly digitize data from showers in nuclear emulsions is described. A TV camera views the emulsions though a microscope. The TV output is superimposed on the monitor of a minicomputer. The operator uses the computer's graphics capability to mark the positions of particle tracks. The coordinates of each track are stored on a disk. The computer then predicts the coordinates of each track through successive layers of emulsion. The operator, guided by the predictions, thus tracks and stores the development of the shower. The system provides a significant improvement over purely manual methods of recording shower development in nuclear emulsion stacks.

  14. Human detection and tracking

    NASA Astrophysics Data System (ADS)

    Yu, Pengxian; Wei, Yaxun

    2013-10-01

    This paper presents a method to segment moving human bodies. A self-adaptive background model is used to update the background image(so-called reference image). By calculating the Euclidean distance of corresponding points in the current and background image, we can check out the foreground objects. And the shadow can be detected and removed according to the characteristics of the shadow regions shown in HSV space. Finally, target tracking is implemented by calculating the relativity of color histogram between the moving areas in two succeeding images.

  15. Track Standing Wave Analysis

    DTIC Science & Technology

    1988-01-01

    Journal of Mechanics, Transmissions and Automation in Design, 126, Vol. 106, pp. 126-132 _N4. (March 1984) 77 Lazan , B . J ., "Damping of Materials and...International Test Operations Procedure (ITOP), "Tracked Vehicle Physical Characteristics" (1984) . Keller, J . B ., "Large Amplitude Motion of a...this configuration were complet ed and tabulated results appear to be reasonable. ON 2 N 0’ J , . ". 0 "W’ -St. yNb j PREFACE The cooperation and

  16. Satellite Tracking System

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Researchers at the Center for Aerospace Sciences of the University of North Dakota (UND), Grand Forks, used three NASA Computer programs (SANDTRACKS, ODG, NORAD) to develop a Satellite Tracking System for real time utilization of TIROS weather/environment satellite information. SANDTRACKS computes the satellite's position relative to the Earth. ODG allows plotting a view of Earth as seen by the satellite. NORAD computes sight direction, visibility times and maximum elevation angle during each orbit. With the system, UND's Earth System Science Institute will be able to routinely monitor agricultural and environmental conditions of the Northern Plains.

  17. Multiple collaborative kernel tracking.

    PubMed

    Fan, Zhimin; Yang, Ming; Wu, Ying

    2007-07-01

    Those motion parameters that cannot be recovered from image measurements are unobservable in the visual dynamic system. This paper studies this important issue of singularity in the context of kernel-based tracking and presents a novel approach that is based on a motion field representation which employs redundant but sparsely correlated local motion parameters instead of compact but uncorrelated global ones. This approach makes it easy to design fully observable kernel-based motion estimators. This paper shows that these high-dimensional motion fields can be estimated efficiently by the collaboration among a set of simpler local kernel-based motion estimators, which makes the new approach very practical.

  18. Tracking speech sound acquisition.

    PubMed

    Powell, Thomas W

    2011-11-01

    This article describes a procedure to aid in the clinical appraisal of child speech. The approach, based on the work by Dinnsen, Chin, Elbert, and Powell (1990; Some constraints on functionally disordered phonologies: Phonetic inventories and phonotactics. Journal of Speech and Hearing Research, 33, 28-37), uses a railway idiom to track gains in the complexity of speech sound production. A clinical case study is reviewed to illustrate application of the procedure. The procedure is intended to facilitate application of an evidence-based procedure to the clinical management of developmental speech sound disorders.

  19. Nuclear photonics

    NASA Astrophysics Data System (ADS)

    Habs, D.; Günther, M. M.; Jentschel, M.; Thirolf, P. G.

    2012-07-01

    With the planned new γ-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest (Romania) with 1013 γ/s and a band width of ΔEγ/Eγ≈10-3, a new era of γ beams with energies up to 20MeV comes into operation, compared to the present world-leading HIγS facility at Duke University (USA) with 108 γ/s and ΔEγ/Eγ≈3ṡ10-2. In the long run even a seeded quantum FEL for γ beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused γ beams. Here we describe a new experiment at the γ beam of the ILL reactor (Grenoble, France), where we observed for the first time that the index of refraction for γ beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for γ beams are being developed. Thus, we have to optimize the total system: the γ-beam facility, the γ-beam optics and γ detectors. We can trade γ intensity for band width, going down to ΔEγ/Eγ≈10-6 and address individual nuclear levels. The term "nuclear photonics" stresses the importance of nuclear applications. We can address with γ-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, γ beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to μm resolution using Nuclear Resonance Fluorescence (NRF) for detection with eV resolution and high spatial resolution at the same time. We discuss the dominating M1 and E1 excitations like the scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of applications. We find many new applications in biomedicine, green energy, radioactive waste management or homeland security. Also more brilliant secondary beams of neutrons and positrons can be produced.

  20. Nuclear photonics

    SciTech Connect

    Habs, D.; Guenther, M. M.; Jentschel, M.; Thirolf, P. G.

    2012-07-09

    With the planned new {gamma}-beam facilities like MEGa-ray at LLNL (USA) or ELI-NP at Bucharest (Romania) with 10{sup 13}{gamma}/s and a band width of {Delta}E{gamma}/E{gamma} Almost-Equal-To 10{sup -3}, a new era of {gamma} beams with energies up to 20MeV comes into operation, compared to the present world-leading HI{gamma}S facility at Duke University (USA) with 10{sup 8}{gamma}/s and {Delta}E{gamma}/E{gamma} Almost-Equal-To 3 Dot-Operator 10{sup -2}. In the long run even a seeded quantum FEL for {gamma} beams may become possible, with much higher brilliance and spectral flux. At the same time new exciting possibilities open up for focused {gamma} beams. Here we describe a new experiment at the {gamma} beam of the ILL reactor (Grenoble, France), where we observed for the first time that the index of refraction for {gamma} beams is determined by virtual pair creation. Using a combination of refractive and reflective optics, efficient monochromators for {gamma} beams are being developed. Thus, we have to optimize the total system: the {gamma}-beam facility, the {gamma}-beam optics and {gamma} detectors. We can trade {gamma} intensity for band width, going down to {Delta}E{gamma}/E{gamma} Almost-Equal-To 10{sup -6} and address individual nuclear levels. The term 'nuclear photonics' stresses the importance of nuclear applications. We can address with {gamma}-beams individual nuclear isotopes and not just elements like with X-ray beams. Compared to X rays, {gamma} beams can penetrate much deeper into big samples like radioactive waste barrels, motors or batteries. We can perform tomography and microscopy studies by focusing down to {mu}m resolution using Nuclear Resonance Fluorescence (NRF) for detection with eV resolution and high spatial resolution at the same time. We discuss the dominating M1 and E1 excitations like the scissors mode, two-phonon quadrupole octupole excitations, pygmy dipole excitations or giant dipole excitations under the new facet of

  1. Variation of the track etch rates of alpha-particle trajectory in PADC

    NASA Astrophysics Data System (ADS)

    Zaki, M. F.; Hegazy, T. M.; Seddik, U.; Morsy, A. A.

    2005-01-01

    The formation of etched tracks in solid-state nuclear track detectors is usually described by assuming an unequivocal correlation of the etch-rate ratio with the energy loss of charged particles. For alpha particles, this assumption could be verified within the scatter of the experimental data. In this article, the dependence of the depth (x) on the track etch rate (V-T) was determined experimentally by track length measurement. It is found that the track etch rate as a function of the depth within the detector follows the Bragg curve. The track etch rate has been found to be described by a generalization of the restricted energy loss, in good approximation along the trajectories of alpha particles.

  2. Proteins Connecting the Nuclear Pore Complex with the Nuclear Interior

    PubMed Central

    Strambio-de-Castillia, Caterina; Blobel, Günter; Rout, Michael P.

    1999-01-01

    While much has been learned in recent years about the movement of soluble transport factors across the nuclear pore complex (NPC), comparatively little is known about intranuclear trafficking. We isolated the previously identified Saccharomyces protein Mlp1p (myosin-like protein) by an assay designed to find nuclear envelope (NE) associated proteins that are not nucleoporins. We localized both Mlp1p and a closely related protein that we termed Mlp2p to filamentous structures stretching from the nucleoplasmic face of the NE into the nucleoplasm, similar to the homologous vertebrate and Drosophila Tpr proteins. Mlp1p can be imported into the nucleus by virtue of a nuclear localization sequence (NLS) within its COOH-terminal domain. Overexpression experiments indicate that Mlp1p can form large structures within the nucleus which exclude chromatin but appear highly permeable to proteins. Remarkably, cells harboring a double deletion of MLP1 and MLP2 were viable, although they showed a slower net rate of active nuclear import and faster passive efflux of a reporter protein. Our data indicate that the Tpr homologues are not merely NPC-associated proteins but that they can be part of NPC-independent, peripheral intranuclear structures. In addition, we suggest that the Tpr filaments could provide chromatin-free conduits or tracks to guide the efficient translocation of macromolecules between the nucleoplasm and the NPC. PMID:10085285

  3. Missile tracking and range safety: Tracking Interferometer Pathfinder System (TIPS)

    NASA Astrophysics Data System (ADS)

    Dowgiallo, David J.; Rauen, Stephen; Peters, Wendy M.; Polisensky, Emil J.

    2013-05-01

    The tracking of missiles at close range proximity has been an ongoing challenge for many launch environments. The ability to provide accurate missile trajectory information is imperative for range safety and early termination of flight. In an effort to provide a potential solution to tracking issues that have plagued many traditional techniques, the Tracking Interferometer Pathfinder System (TIPS) was developed at the Naval Research Laboratory, Washington, D.C. The paper herein describes the design, field test, and results of an interferometer deployed for missile tracking.

  4. Dust Devil Tracks

    NASA Astrophysics Data System (ADS)

    Reiss, Dennis; Fenton, Lori; Neakrase, Lynn; Zimmerman, Michael; Statella, Thiago; Whelley, Patrick; Rossi, Angelo Pio; Balme, Matthew

    2016-11-01

    Dust devils that leave dark- or light-toned tracks are common on Mars and they can also be found on the Earth's surface. Dust devil tracks (hereinafter DDTs) are ephemeral surface features with mostly sub-annual lifetimes. Regarding their size, DDT widths can range between ˜1 m and ˜1 km, depending on the diameter of dust devil that created the track, and DDT lengths range from a few tens of meters to several kilometers, limited by the duration and horizontal ground speed of dust devils. DDTs can be classified into three main types based on their morphology and albedo in contrast to their surroundings; all are found on both planets: (a) dark continuous DDTs, (b) dark cycloidal DDTs, and (c) bright DDTs. Dark continuous DDTs are the most common type on Mars. They are characterized by their relatively homogenous and continuous low albedo surface tracks. Based on terrestrial and martian in situ studies, these DDTs most likely form when surficial dust layers are removed to expose larger-grained substrate material (coarse sands of ≥500 μm in diameter). The exposure of larger-grained materials changes the photometric properties of the surface; hence leading to lower albedo tracks because grain size is photometrically inversely proportional to the surface reflectance. However, although not observed so far, compositional differences (i.e., color differences) might also lead to albedo contrasts when dust is removed to expose substrate materials with mineralogical differences. For dark continuous DDTs, albedo drop measurements are around 2.5 % in the wavelength range of 550-850 nm on Mars and around 0.5 % in the wavelength range from 300-1100 nm on Earth. The removal of an equivalent layer thickness around 1 μm is sufficient for the formation of visible dark continuous DDTs on Mars and Earth. The next type of DDTs, dark cycloidal DDTs, are characterized by their low albedo pattern of overlapping scallops. Terrestrial in situ studies imply that they are formed when sand

  5. Cassini Archive Tracking System

    NASA Technical Reports Server (NTRS)

    Conner, Diane; Sayfi, Elias; Tinio, Adrian

    2006-01-01

    The Cassini Archive Tracking System (CATS) is a computer program that enables tracking of scientific data transfers from originators to the Planetary Data System (PDS) archives. Without CATS, there is no systematic means of locating products in the archive process or ensuring their completeness. By keeping a database of transfer communications and status, CATS enables the Cassini Project and the PDS to efficiently and accurately report on archive status. More importantly, problem areas are easily identified through customized reports that can be generated on the fly from any Web-enabled computer. A Web-browser interface and clearly defined authorization scheme provide safe distributed access to the system, where users can perform functions such as create customized reports, record a transfer, and respond to a transfer. CATS ensures that Cassini provides complete science archives to the PDS on schedule and that those archives are available to the science community by the PDS. The three-tier architecture is loosely coupled and designed for simple adaptation to multimission use. Written in the Java programming language, it is portable and can be run on any Java-enabled Web server.

  6. Automated call tracking systems

    SciTech Connect

    Hardesty, C.

    1993-03-01

    User Services groups are on the front line with user support. We are the first to hear about problems. The speed, accuracy, and intelligence with which we respond determines the user`s perception of our effectiveness and our commitment to quality and service. To keep pace with the complex changes at our sites, we must have tools to help build a knowledge base of solutions, a history base of our users, and a record of every problem encountered. Recently, I completed a survey of twenty sites similar to the National Energy Research Supercomputer Center (NERSC). This informal survey reveals that 27% of the sites use a paper system to log calls, 60% employ homegrown automated call tracking systems, and 13% use a vendor-supplied system. Fifty-four percent of those using homegrown systems are exploring the merits of switching to a vendor-supplied system. The purpose of this paper is to provide guidelines for evaluating a call tracking system. In addition, insights are provided to assist User Services groups in selecting a system that fits their needs.

  7. NORAD satellite tracking

    NASA Technical Reports Server (NTRS)

    Liu, Joseph J. F.

    1987-01-01

    NORAD routinely tracks about 6000 orbiting objects. During the last 30 days of orbital time, prior to reentry, special perturbations are used in the orbital update procedure. Besides routine orbit determination, NORAD does special tasks such as predicting satellite orbit conjunctions within 20 km, ephimerides of weather satellites, satellite decay predictions and other studies. Since their mission is operational, they do not store the data from their analyses. The ballistic coefficient is not known for most of the orbiting objects. If a ballistic coefficient were derived that was consistent with one density model, it might give erroneous results if used with a different density model. Given the ballistic coefficient, density values could, in principle, be obtained from their tracking data. The densities would represent an integrated mean over the orbital path near perigee. They would be model dependent and would not necessarily represent the real density. In summary, the primary need is for reliable forecasts of solar flux (F10.7) and geomagnetic activity (Ap) in the 1 to 4 week time scale. Forecasts over longer time spans would also be useful for special projects.

  8. The Nuclear Power/Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Totten, Sam; Totten, Martha Wescoat

    1985-01-01

    Once they have nuclear power, most countries will divert nuclear materials from commercial to military programs. In excerpts from the book "Facing the Danger" (by Totten, S. and M. W., Crossing Press, 1984), five anti-nuclear activists explain how and why they have been addressing the nuclear connection. (RM)

  9. The Nuclear Power and Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Leventhal, Paul

    1990-01-01

    Explains problems enforcing the Nuclear Non-Proliferation Treaty (NPT) of 1968. Provides factual charts and details concerning the production of nuclear energy and arms, the processing and disposal of waste products, and outlines the nuclear fuel cycle. Discusses safeguards, the risk of nuclear terrorism, and ways to deal with these problems. (NL)

  10. The Nuclear Power and Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Leventhal, Paul

    1990-01-01

    Explains problems enforcing the Nuclear Non-Proliferation Treaty (NPT) of 1968. Provides factual charts and details concerning the production of nuclear energy and arms, the processing and disposal of waste products, and outlines the nuclear fuel cycle. Discusses safeguards, the risk of nuclear terrorism, and ways to deal with these problems. (NL)

  11. The Nuclear Power/Nuclear Weapons Connection.

    ERIC Educational Resources Information Center

    Totten, Sam; Totten, Martha Wescoat

    1985-01-01

    Once they have nuclear power, most countries will divert nuclear materials from commercial to military programs. In excerpts from the book "Facing the Danger" (by Totten, S. and M. W., Crossing Press, 1984), five anti-nuclear activists explain how and why they have been addressing the nuclear connection. (RM)

  12. Presentation on Improved Tracking Cameras

    NASA Image and Video Library

    2003-10-08

    Inside the dome building at Playalinda Beach, Bob Fore points to a map of camera sites during a presentation to the media on the improved tracking cameras and long-range optical tracking systems that will be used to capture ascent imagery during the return to flight of the Space Shuttle. The press opportunity also includes tours of the launch pad perimeter camera site at Launch Complex 39B and the other optical tracking site at the Merritt Island National Refuge.

  13. Presentation on Improved Tracking Cameras

    NASA Image and Video Library

    2003-10-08

    Inside the dome building at Playalinda Beach, Mike Litscher talks to media about the Distant Object Attitude Measurement System (DOAMS), part of the improved tracking cameras and long-range optical tracking systems that will be used to capture ascent imagery during the return to flight of the Space Shuttle. The press opportunity also includes tours of the launch pad perimeter camera site at Launch Complex 39B and the other optical tracking site at the Merritt Island National Refuge.

  14. Bayesian Tracking of Visual Objects

    NASA Astrophysics Data System (ADS)

    Zheng, Nanning; Xue, Jianru

    Tracking objects in image sequences involves performing motion analysis at the object level, which is becoming an increasingly important technology in a wide range of computer video applications, including video teleconferencing, security and surveillance, video segmentation, and editing. In this chapter, we focus on sequential Bayesian estimation techniques for visual tracking. We first introduce the sequential Bayesian estimation framework, which acts as the theoretic basis for visual tracking. Then, we present approaches to constructing representation models for specific objects.

  15. REC Tracking Systems Design Guide

    SciTech Connect

    Meredith Wingate

    2004-02-03

    OAK-B135 The Design Guide is presented in three parts. Section II describes the need for REC tracking, the two principal tracking methods available, and, in simple terms, the operation of certificate-based systems. Section III presents the major issues in the design of certificate-based tracking systems and discusses the advantages and disadvantages of alternative solutions. Finally, Section IV offers design principles or recommendations for most of these issues.

  16. Eye tracking in infancy research.

    PubMed

    Gredebäck, Gustaf; Johnson, Scott; von Hofsten, Claes

    2010-01-01

    The current review offers a unique introduction to the use of corneal reflection eye tracking in infancy research. We provide a detailed description of how to calibrate, collect, and analyze infants' gaze in a series of experimental paradigms, focusing specifically on the analysis of visual tracking, point of gaze, and the latency of gaze shifts (prediction and reactive gaze shifts). The article ends with a critical discussion about the pros and cons of corneal reflection eye tracking.

  17. NUCLEAR REACTORS

    DOEpatents

    Long, E.; Ashley, J.W.

    1958-12-16

    A graphite moderator structure is described for a gas-cooled nuclear reactor having a vertical orlentation wherein the structure is physically stable with regard to dlmensional changes due to Wigner growth properties of the graphite, and leakage of coolant gas along spaces in the structure is reduced. The structure is comprised of stacks of unlform right prismatic graphite blocks positioned in layers extending in the direction of the lengths of the blocks, the adjacent end faces of the blocks being separated by pairs of tiles. The blocks and tiles have central bores which are in alignment when assembled and are provided with cooperatlng keys and keyways for physical stability.

  18. Nuclear energy.

    PubMed

    Grandin, Karl; Jagers, Peter; Kullander, Sven

    2010-01-01

    Nuclear energy can play a role in carbon free production of electrical energy, thus making it interesting for tomorrow's energy mix. However, several issues have to be addressed. In fission technology, the design of so-called fourth generation reactors show great promise, in particular in addressing materials efficiency and safety issues. If successfully developed, such reactors may have an important and sustainable part in future energy production. Working fusion reactors may be even more materials efficient and environmental friendly, but also need more development and research. The roadmap for development of fourth generation fission and fusion reactors, therefore, asks for attention and research in these fields must be strengthened.

  19. Nuclear security

    SciTech Connect

    Dingell, J.D.

    1991-02-01

    The Department of Energy's (DOE) Lawrence Livermore National Laboratory, located in Livermore, California, generates and controls large numbers of classified documents associated with the research and testing of nuclear weapons. Concern has been raised about the potential for espionage at the laboratory and the national security implications of classified documents being stolen. This paper determines the extent of missing classified documents at the laboratory and assesses the adequacy of accountability over classified documents in the laboratory's custody. Audit coverage was limited to the approximately 600,000 secret documents in the laboratory's custody. The adequacy of DOE's oversight of the laboratory's secret document control program was also assessed.

  20. Nuclear dualism.

    PubMed

    Karrer, Kathleen M

    2012-01-01

    Nuclear dualism is a characteristic feature of the ciliated protozoa. Tetrahymena have two different nuclei in each cell. The larger, polyploid, somatic macronucleus (MAC) is the site of transcriptional activity in the vegetatively growing cell. The smaller, diploid micronucleus (MIC) is transcriptionally inactive in vegetative cells, but is transcriptionally active in mating cells and responsible for the genetic continuity during sexual reproduction. Although the MICs and MACs develop from mitotic products of a common progenitor and reside in a common cytoplasm, they are different from one another in almost every respect. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Applications of nuclear physics

    DOE PAGES

    Hayes-Sterbenz, Anna Catherine

    2017-01-10

    Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applicationsmore » of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Lastly, each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.« less

  2. Applications of nuclear physics.

    PubMed

    Hayes, A C

    2017-02-01

    Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applications of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.

  3. Applications of nuclear physics

    NASA Astrophysics Data System (ADS)

    Hayes, A. C.

    2017-02-01

    Today the applications of nuclear physics span a very broad range of topics and fields. This review discusses a number of aspects of these applications, including selected topics and concepts in nuclear reactor physics, nuclear fusion, nuclear non-proliferation, nuclear-geophysics, and nuclear medicine. The review begins with a historic summary of the early years in applied nuclear physics, with an emphasis on the huge developments that took place around the time of World War II, and that underlie the physics involved in designs of nuclear explosions, controlled nuclear energy, and nuclear fusion. The review then moves to focus on modern applications of these concepts, including the basic concepts and diagnostics developed for the forensics of nuclear explosions, the nuclear diagnostics at the National Ignition Facility, nuclear reactor safeguards, and the detection of nuclear material production and trafficking. The review also summarizes recent developments in nuclear geophysics and nuclear medicine. The nuclear geophysics areas discussed include geo-chronology, nuclear logging for industry, the Oklo reactor, and geo-neutrinos. The section on nuclear medicine summarizes the critical advances in nuclear imaging, including PET and SPECT imaging, targeted radionuclide therapy, and the nuclear physics of medical isotope production. Each subfield discussed requires a review article unto itself, which is not the intention of the current review; rather, the current review is intended for readers who wish to get a broad understanding of applied nuclear physics.

  4. Faculty achievement tracking tool.

    PubMed

    Pettus, Sarah; Reifschneider, Ellen; Burruss, Nancy

    2009-03-01

    Faculty development and scholarship is an expectation of nurse educators. Accrediting institutions, such as the Commission on Collegiate Nursing Education, the National League for Nursing Accrediting Commission, and the Higher Learning Commission, all have criteria regarding faculty achievement. A faculty achievement tracking tool (FATT) was developed to facilitate documentation of accreditation criteria attainment. Based on criteria from accrediting organizations, the roles that are addressed include scholarship, service, and practice. Definitions and benchmarks for the faculty as an aggregate are included. Undergoing reviews from different accrediting organizations, the FATT has been used once for accreditation of the undergraduate program and once for accreditation of the graduate program. The FATT is easy to use and has become an excellent adjunct for the preparation for accreditation reports. In addition, the FATT may be used for yearly evaluations, advancement, and merit.

  5. Track-and-Trench

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image shows the tracks and trench marks made by the Mars Exploration Rover Opportunity at Meridiani Planum, Mars. The rover can be seen to the lower left of the lander. The trench is visible to the upper left of the rover, which has traveled a total of 35.3 meters (116 feet) since leaving the lander on sol 7 (January 31, 2004). On sol 23 (February 16, 2004), the rover used one of its wheels to dig a trench measuring approximately 10 centimeters (4 inches) deep, 50 centimeters (20 inches) long, and 20 centimeters (8 inches) wide. This vertically projected image was created using a combination of images from the rover's navigation camera and hazard-avoidance cameras.

  6. Solar tracking system

    NASA Technical Reports Server (NTRS)

    White, P. R.; Scott, D. R. (Inventor)

    1981-01-01

    A solar tracker for a solar collector is described in detail. The collector is angularly oriented by a motor wherein the outputs of two side-by-side photodetectors are discriminated as to three ranges: a first corresponding to a low light or darkness condition; a second corresponding to light intensity lying in an intermediate range; and a third corresponding to light above an intermediate range, direct sunlight. The first output drives the motor to a selected maximum easterly angular position; the second enables the motor to be driven westerly at the Earth rotational rate; and the third output, the separate outputs of the two photodetectors, differentially controls the direction of rotation of the motor to effect actual tracking of the Sun.

  7. Solar tracking system

    NASA Astrophysics Data System (ADS)

    White, P. R.; Scott, D. R.

    1981-04-01

    A solar tracker for a solar collector is described in detail. The collector is angularly oriented by a motor wherein the outputs of two side-by-side photodetectors are discriminated as to three ranges: a first corresponding to a low light or darkness condition; a second corresponding to light intensity lying in an intermediate range; and a third corresponding to light above an intermediate range, direct sunlight. The first output drives the motor to a selected maximum easterly angular position; the second enables the motor to be driven westerly at the Earth rotational rate; and the third output, the separate outputs of the two photodetectors, differentially controls the direction of rotation of the motor to effect actual tracking of the Sun.

  8. Intrinsic Feature Motion Tracking

    SciTech Connect

    Goddard, Jr., James S.

    2013-03-19

    Subject motion during 3D medical scanning can cause blurring and artifacts in the 3D images resulting in either rescans or poor diagnosis. Anesthesia or physical restraints may be used to eliminate motion but are undesirable and can affect results. This software measures the six degree of freedom 3D motion of the subject during the scan under a rigidity assumption using only the intrinsic features present on the subject area being monitored. This movement over time can then be used to correct the scan data removing the blur and artifacts. The software acquires images from external cameras or images stored on disk for processing. The images are from two or three calibrated cameras in a stereo arrangement. Algorithms extract and track the features over time and calculate position and orientation changes relative to an initial position. Output is the 3D position and orientation change measured at each image.

  9. Intelligent tracking techniques

    NASA Astrophysics Data System (ADS)

    Willett, T. J.; Abruzzo, J.; Zagardo, V.; Shipley, J.; Kossa, L.

    1980-10-01

    This is the fifth quarterly report under a contract to investigate the design, test, and implementation of a set of algorithms to perform intelligent tracking and intelligent homing on FLIR and TV imagery. The system concept was described. The problem of target aspect determination in support of aimpoint selection was analyzed. Sequences of 875 line FLIR data were extracted from the data base and an example of aspect determination for a maneuvering target in the presence of obscurations was presented. An example was also presented for close in homing (less than 500 meters) and the emergence of interior features, target movement, and scale changes. Hardware implementation in terms of VLSI/VHSIC chips was analyzed.

  10. The "mommy tenure track".

    PubMed

    Draznin, Julia

    2004-04-01

    For years women have been fighting for equity in the academic work place, but this acceptance comes at a price. Balancing work and family obligations have proven to be an awkward task where maximal satisfaction and gratification in both are not easily attained. Junior-level faculty have the arduous charge of being most productive and prolific exactly during their child-raising years. If our society wants to produce and maintain women professionals, then academic institutions have to be more generous and tolerant in the short-term for a long-term gain. The author proposes a "mommy tenure track" in which primary caregivers of infants are allowed to temporarily postpone their tenure clock. She also cites innovative initiatives being carried out at one institution to help women, including young mothers, with their academic careers and promotions.

  11. Geo Issue Tracking System

    NASA Astrophysics Data System (ADS)

    Khakpour, Mohammad; Paulik, Christoph; Hahn, Sebastian

    2016-04-01

    Communication about remote sensing data quality between data providers and users as well as between the users is often difficult. The users have a hard time figuring out if a product has known problems over their region of interest and data providers have to spend a lot of effort to make this information available, if it exists. Scientific publications are one tool for communicating with the users base but they are static and mostly one way. As a data provider it is also often difficult to make feedback, received from users, available to the complete user base. The Geo Issue Tracking System (GeoITS) is an Open Source Web Application which has been developed to mitigate these problems. GeoITS combines a mapping interface (Google Maps) with a simple wiki platform. It allows users to give region specific feedback on a remote sensing product by drawing a polygon on the map and describing the problems they had using the remote sensing product in this area. These geolocated wiki entries are then viewable by other users as well as the data providers which can modify and extend the entries. In this way the conversations between the users and the data provider are no longer hidden in e.g. emails but open for all users of the dataset. This new kind of communication platform can enable better cooperation between users and data providers. It will also provide data providers with the ability to track problems their dataset might have in certain areas and resolve them with new product releases. The source code is available via http://github.com/TUW-GEO/geoits_dev A running instance can be tried at https://geoits.herokuapp.com/

  12. Nuclear "waffles"

    NASA Astrophysics Data System (ADS)

    Schneider, A. S.; Berry, D. K.; Briggs, C. M.; Caplan, M. E.; Horowitz, C. J.

    2014-11-01

    Background: The dense neutron-rich matter found in supernovae and inside neutron stars is expected to form complex nonuniform phases, often referred to as nuclear pasta. The pasta shapes depend on density, temperature and proton fraction and determine many transport properties in supernovae and neutron star crusts. Purpose: To characterize the topology and compute two observables, the radial distribution function (RDF) g (r ) and the structure factor S (q ) , for systems with proton fractions Yp=0.10 ,0.20 ,0.30 , and 0.40 at about one-third of nuclear saturation density, n =0.050 fm-3 , and temperatures near k T =1 MeV . Methods: We use two recently developed hybrid CPU/GPU codes to perform large scale molecular dynamics (MD) simulations with 51 200 and 409 600 nucleons. From the output of the MD simulations we obtain the two desired observables. Results: We compute and discuss the differences in topology and observables for each simulation. We observe that the two lowest proton fraction systems simulated, Yp=0.10 and 0.20 , equilibrate quickly and form liquidlike structures. Meanwhile, the two higher proton fraction systems, Yp=0.30 and 0.40 , take a longer time to equilibrate and organize themselves in solidlike periodic structures. Furthermore, the Yp=0.40 system is made up of slabs, lasagna phase, interconnected by defects while the Yp=0.30 systems consist of a stack of perforated plates, the nuclear waffle phase. Conclusions: The periodic configurations observed in our MD simulations for proton fractions Yp≥0.30 have important consequences for the structure factors S (q ) of protons and neutrons, which relate to many transport properties of supernovae and neutron star crust. A detailed study of the waffle phase and how its structure depends on temperature, size of the simulation, and the screening length showed that finite-size effects appear to be under control and, also, that the plates in the waffle phase merge at temperatures slightly above 1.0 MeV and

  13. Condensed Matter Nuclear Science

    NASA Astrophysics Data System (ADS)

    Takahashi, Akito; Ota, Ken-Ichiro; Iwamura, Yashuhiro

    element on multi-layered Pd sample by deuterium permeation / H. Yamada ... [et al.]. Experimental observation and combined investigation of high-performance fusion of iron-region isotopes in optimal growing microbiological associations / V. I. Vysotskii ... [et al.]. Research into low-energy nuclear reactions in cathode sample solid with production of excess heat, stable and radioactive impurity nuclides / A. B. Karabut. Influence of parameters of the glow discharge on change of structure and the isotope composition of the cathode materials / I. B. Savvatimova and D. V. Gavritenkov. Elemental analysis of palladium electrodes after Pd/Pd light water critical electrolysis / Y. Toriyabe ... [et al.]. Progress on the study of isotopic composition in metallic thin films undergone to electrochemical loading of hydrogen / M. Apicella ... [et al.]. In situ accelerator analyses of palladium complex under deuterium permeation / A. Kitamura ... [et al.]. High-resolution mass spectrum for deuterium (hydrogen) gas permeating palladium film / Q. M. Wei ... [et al.]. ICP-MS analysis of electrodes and electrolytes after HNO[symbol]/H[symbol]O electrolysis / S. Taniguchi ... [et al.]. The Italy-Japan project - fundamental research on cold transmutation process for treatment of nuclear wastes / A. Takahashi, F. Celani and Y. Iwamura -- 4. Nuclear physics approach. Reproducible nuclear emissions from Pd/PdO:Dx heterostructure during controlled exothermic deuterium desorption / A. G. Lipson ... [et al.]. Correct identification of energetic alpha and proton tracks in experiments on CR-39 charged particle detection during hydrogen desorption from Pd/PdO:H[symbol] heterostructure / A. S. Roussetski ... [et al.]. Intense non-linear soft X-ray emission from a hydride target during pulsed D bombardment / G. H. Miley ... [et al.]. Enhancement of first wall damage in ITER type TOKAMAK due to LENR effects / A. G. Lipson, G. H. Miley and H. Momota. Generation of DD-reactions in a ferroelectric KD

  14. Muon trackers for imaging a nuclear reactor

    NASA Astrophysics Data System (ADS)

    Kume, N.; Miyadera, H.; Morris, C. L.; Bacon, J.; Borozdin, K. N.; Durham, J. M.; Fuzita, K.; Guardincerri, E.; Izumi, M.; Nakayama, K.; Saltus, M.; Sugita, T.; Takakura, K.; Yoshioka, K.

    2016-09-01

    A detector system for assessing damage to the cores of the Fukushima Daiichi nuclear reactors by using cosmic-ray muon tomography was developed. The system consists of a pair of drift-tube tracking detectors of 7.2× 7.2-m2 area. Each muon tracker consists of 6 x-layer and 6 y-layer drift-tube detectors. Each tracker is capable of measuring muon tracks with 12 mrad angular resolutions, and is capable of operating under 50-μ Sv/h radiation environment by removing gamma induced background with a novel time-coincidence logic. An estimated resolution to observe nuclear fuel debris at Fukushima Daiichi is 0.3 m when the core is imaged from outside the reactor building.

  15. Improved code-tracking loop

    NASA Technical Reports Server (NTRS)

    Laflame, D. T.

    1980-01-01

    Delay-locked loop tracks pseudonoise codes without introducing dc timing errors, because it is not sensitive to gain imbalance between signal processing arms. "Early" and "late" reference codes pass in combined form through both arms, and each arm acts on both codes. Circuit accomodates 1 dB weaker input signals with tracking ability equal to that of tau-dither loops.

  16. Making Sense of Dinosaur Tracks

    ERIC Educational Resources Information Center

    MacKenzie, Ann Haley; McDowell, Brian

    2012-01-01

    What do paleontologists, dinosaur tracks, and the nature of science have in common? They're combined here in an inquiry activity where students use methods of observation and inference to devise evidence-based explanations for the data they collect about dinosaur tracks, much like the methods used by paleontologists. Students then debate the…

  17. SRNL Tagging and Tracking Video

    SciTech Connect

    2016-05-18

    SRNL generates a next generation satellite base tracking system. The tagging and tracking system can work in remote wilderness areas, inside buildings, underground and other areas not well served by traditional GPS. It’s a perfect response to customer needs and market demand.

  18. SRNL Tagging and Tracking Video

    ScienceCinema

    None

    2016-07-12

    SRNL generates a next generation satellite base tracking system. The tagging and tracking system can work in remote wilderness areas, inside buildings, underground and other areas not well served by traditional GPS. It’s a perfect response to customer needs and market demand.

  19. Buyer's Guide for Track Construction.

    ERIC Educational Resources Information Center

    United States Tennis Court & Track Builders Association.

    This buyers guide provides information on needs assessment, buying options, and decision making tips when acquiring a new school athletic track. Among the topics covered are developing a budget, choosing a site selection, choosing a track surface, developing working specifications, and selecting a contractor. Also explored is the question of…

  20. CONTRACT ADMINISTRATIVE TRACKING SYSTEM (CATS)

    EPA Science Inventory

    The Contract Administrative Tracking System (CATS) was developed in response to an ORD NHEERL, Mid-Continent Ecology Division (MED)-recognized need for an automated tracking and retrieval system for Cost Reimbursable Level of Effort (CR/LOE) Contracts. CATS is an Oracle-based app...