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Sample records for clementine reactor

  1. The Clementine satellite

    SciTech Connect

    Not Available

    1994-06-01

    The first US satellite to the Moon in more than two decades was launched from Vandenberg Air Force Base (Santa Barbara County), California, on January 25, 1994. The satellite was named Clementine because it carried only enough fuel to complete its mission before it was [open quotes]lost and gone forever.[close quotes] The Clementine satellite tested 23 advanced technologies during its mission for the Ballistic Missile Defense Organization. In fulfilling its scientific goals, Clementine provided a wealth of information relevant to the mineralogy of the lunar surface. Using six on-board cameras designed and built at the Laboratory, Clementine mapped the entire surface of the Moon at resolutions never before attained. Clementine also provided range data that will be used to construct a relief map of the lunar surface.

  2. The Clementine instrument complement

    NASA Technical Reports Server (NTRS)

    Lucey, Paul G.

    1993-01-01

    The recent successes of the Galileo solid-state imaging (SSI) experiment at the Moon and Gaspra show the utility of multispectral imaging of planetary objects. 'Clementine' is the planetary community's 'code name' for the SDIO (Space Defense Initiative Organization), mission to the Moon and the asteroid Geographos. This mission is designed as a long term stressing test on sensors and space systems developed for SDIO. In the course of this test Clementine will obtain science data using a varied and powerful array of remote sensing instruments which were developed by or for Lawrence Livermore National Laboratory in Livermore, California. Clementine carries five cameras, one for navigation and four for science experiments. In addition, a laser ranger is included which will serve as a laser altimeter. The Clementine cameras cover a wider range of spatial resolutions and wavelength range than did Galileo and are almost ideally suited to mapping of mafic rock types as are present on the Moon and expected at Geographos. Calibration of the cameras will occur at the sensor calibration laboratory at LLNL. In flight calibrations, using standard stars and other standards should improve the stated accuracies. Signal-to-noise ratios (SNRs) include the following noise sources: shot noise, calibration error, digitization noise, readout noise, and frame transfer noise (where applicable). The achieved SNRs are a balance between detector saturation and acceptable image smear. The 'worst' case uses the longest possible integration times.

  3. Clementine sensor suite

    SciTech Connect

    Ledebuhr, A.G.

    1994-11-15

    LLNL designed and built the suite of six miniaturized light-weight space-qualified sensors utilized in the Clementine mission. A major goal of the Clementine program was to demonstrate technologies originally developed for Ballistic Missile Defense Organization Programs. These sensors were modified to gather data from the moon. This overview presents each of these sensors and some preliminary on-orbit performance estimates. The basic subsystems of these sensors include optical baffles to reject off-axis stray light, light-weight ruggedized optical systems, filter wheel assemblies, radiation tolerant focal plane arrays, radiation hardened control and readout electronics and low mass and power mechanical cryogenic coolers for the infrared sensors. Descriptions of each sensor type are given along with design specifications, photographs and on-orbit data collected.

  4. The Clementine mechanisms

    NASA Technical Reports Server (NTRS)

    Purdy, William; Hurley, Michael

    1995-01-01

    The Clementine spacecraft was developed under the 'faster, better, cheaper' theme. The constraints of a low budget coupled with an unusually tight schedule forced many departures from the normal spacecraft development methods. This paper discusses technical lessons learned about several of the mechanisms on the Clementine spacecraft as well as managerial lessons learned for the entire mechanisms subsystem. A quick overview of the Clementine mission is included; the mission schedule and environment during the mechanisms releases and deployment are highlighted. This paper then describes the entire mechanisms subsystem. The design and test approach and key philosophies for a fast-track program are discussed during the description of the mechanisms subsystem. The mechanism subsystem included a marman clamp separation system, a separation nut separation system, a solar panel deployment and pointing system, a high gain antenna feed deployment system, and two separate sensor cover systems. Each mechanism is briefly discussed. Additional technical discussion is given on the marman clamp design, the sensor cover designs, and the design and testing practices for systems driven by heated actuators (specifically paraffin actuators and frangibolts). All of the other mechanisms were of conventional designs and will receive less emphasis. Lessons learned are discussed throughout the paper as they applied to the systems being discussed. Since there is information on many different systems, this paper is organized so that information on a particular topic can be quickly referenced.

  5. Clementine RRELAX SRAM Particle Spectrometer

    NASA Technical Reports Server (NTRS)

    Buehler, M.; Soli, G.; Blaes, B.; Ratliff, J.; Garrett, H.

    1994-01-01

    The Clementine RRELAX radiation monitor chip consists of a p-FET total dose monitor and a 4-kbit SRAM particle spectrometer. Eight of these chips were included in the RRELAX and used to detect the passage of the Clementine (S/C) and the innerstage adapter (ISA) through the earth's radiation belts and the 21-Feb 1994 solar flare. This is the first space flight for this 1.2 micron rad-soft custom CMOS radiation monitor. This paper emphasizes results from the SRAM particle detector which showed that it a) has a detection range of five orders of magnitude relative to the 21-Feb solar flare, b) is not affected by electrons, and c) detected microflares occurring with a 26.5 day period.

  6. 7 CFR 319.56-34 - Clementines from Spain.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Clementines from Spain. 319.56-34 Section 319.56-34... Clementines from Spain. Clementines (Citrus reticulata) from Spain may only be imported into the United States... agreement. Clementines from Spain may be imported only if the Government of Spain or its...

  7. The Clementine bistatic radar experiment

    USGS Publications Warehouse

    Nozette, S.; Lichtenberg, C.L.; Spudis, P.; Bonner, R.; Ort, W.; Malaret, E.; Robinson, M.; Shoemaker, E.M.

    1996-01-01

    During the Clementine 1 mission, a bistatic radar experiment measured the magnitude and polarization of the radar echo versus bistatic angle, ??, for selected lunar areas. Observations of the lunar south pole yield a same- sense polarization enhancement around ?? = 0. Analysis shows that the observed enhancement is localized to the permanently shadowed regions of the lunar south pole. Radar observations of periodically solar-illuminated lunar surfaces, including the north pole, yielded no such enhancement. A probable explanation for these differences is the presence of low-loss volume scatterers, such as water ice, in the permanently shadowed region at the south pole.

  8. The Clementine bistatic radar experiment.

    PubMed

    Nozette, S; Lichtenberg, C L; Spudis, P; Bonner, R; Ort, W; Malaret, E; Robinson, M; Shoemaker, E M

    1996-11-29

    During the Clementine 1 mission, a bistatic radar experiment measured the magnitude and polarization of the radar echo versus bistatic angle, beta, for selected lunar areas. Observations of the lunar south pole yield a same-sense polarization enhancement around beta = 0. Analysis shows that the observed enhancement is localized to the permanently shadowed regions of the lunar south pole. Radar observations of periodically solar-illuminated lunar surfaces, including the north pole, yielded no such enhancement. A probable explanation for these differences is the presence of low-loss volume scatterers, such as water ice, in the permanently shadowed region at the south pole.

  9. The Clementine Bistatic Radar Experiment

    NASA Technical Reports Server (NTRS)

    Nozette, S.; Lichtenberg, C. L.; Spudis, P.; Bonner, R.; Ort, W.; Malaret, E.; Robinson, M.; Shoemaker, E. M.

    1996-01-01

    During the Clementine 1 mission, a bistatic radar experiment measured the magnitude and polarization of the radar echo versus bistatic angle, beta, for selected lunar areas. Observations of the lunar south pole yield a same-sense polarization enhancement around beta = 0. Analysis shows that the observed enhancement is localized to the permanently shadowed regions of the lunar south pole. Radar observations of periodically solar-illuminated lunar surfaces, including the north pole, yielded no such enhancement. A probable explanation for these differences is the presence of low-loss volume scatterers, such as water ice, in the permanently shadowed region at the south pole.

  10. Clementine auto exposure control software

    SciTech Connect

    Arnold, E.

    1994-11-15

    The primary mission of the Clementine program was to test technology developed under the auspices of BMDO (the Ballistic Missile Defense Organization). A secondary goal of the program was to provide astronomical data to the scientific and educational community. The mission plan developed to accomplish these goals included complete mapping of the lunar surface and a close fly-by of a near-Earth asteroid, 1620 Geographos. Exposure control for the Clementine mission was driven by mission phase requirements and sensor characteristics. Thus, there were a total of twelve algorithms developed for three primary mission phases and the four imaging sensors (two additional sensors operated as star trackers). The three mission phases in question were lunar mapping, distant observation of the asteroid for the purpose of tracking, and close-up viewing (as close as 100 Km) of Geographos. The four non-star tracker sensors consisted of an Ultra Violet/Visible (UV/Vis) camera, a High Resolution (HiRes) camera with a built-in LIDAR (Light Detection And Ranging) unit, a Near Infrared (NIR) camera, and a Long Wave InfraRed (LWIR) camera. Due to lack of test time and uncertainties about the imaging environment, numerous input parameters were provided in the algorithms to allow extensive tuning of the exposure control during the mission.

  11. 7 CFR 319.56-34 - Clementines from Spain.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... States, prior to cold treatment, inspectors will cut and inspect a sample of clementines determined by... the export program for the remainder of that shipping season. (g) Cold treatment. Clementines must be cold treated in accordance with part 305 of this chapter. Upon arrival of clementines at a port...

  12. 7 CFR 319.56-34 - Clementines from Spain.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... States, prior to cold treatment, inspectors will cut and inspect a sample of clementines determined by... the export program for the remainder of that shipping season. (g) Cold treatment. Clementines must be cold treated in accordance with part 305 of this chapter. Upon arrival of clementines at a port...

  13. The Clementine longwave infrared camera

    SciTech Connect

    Priest, R.E.; Lewis, I.T.; Sewall, N.R.; Park, H.S.; Shannon, M.J.; Ledebuhr, A.G.; Pleasance, L.D.; Massie, M.A.; Metschuleit, K.

    1995-04-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. The longwave-infrared (LWIR) camera supplemented the UV/Visible and near-infrared mapping cameras providing limited strip coverage of the moon, giving insight to the thermal properties of the soils. This camera provided {approximately}100 m spatial resolution at 400 km periselene, and a 7 km across-track swath. This 2.1 kg camera using a 128 x 128 Mercury-Cadmium-Telluride (MCT) FPA viewed thermal emission of the lunar surface and lunar horizon in the 8.0 to 9.5 {micro}m wavelength region. A description of this light-weight, low power LWIR camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights.

  14. Comparative genetic mapping between clementine, pummelo and sweet orange and the interspecicic structure of the Clementine genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Comparative genetic mapping between clementine, pummelo and sweet orange and the interspecicic structure of the Clementine genome The availability of a saturated genetic map of Clementine was identified by the International Citrus Genome Consortium as an essential prerequisite to assist the assembly...

  15. Clementine, Deep Space Program Science Experiment

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Clementine, also called the Deep Space Program Science Experiment, is a joint Department of Defense (DoD)/National Aeronautics and Space Administration (NASA) mission with the dual goal of testing small spacecraft, subsystems, and sensors in the deep space environment and also providing a nominal science return. The Clementine mission will provide technical demonstrations of innovative lightweight spacecraft components and sensors, will be launced on a spacecraft developed within 2 years of program start, and will point a way for new planetary mission options under consideration by NASA. This booklet gives the background of the Clementine mission (including the agencies involved), the mission objectives, the mission scenario, the instruments that the mission will carry, and how the data will be analyzed and made accessible.

  16. Lessons Learned from the Clementine Mission

    NASA Technical Reports Server (NTRS)

    1997-01-01

    According to BMDO, the Clementine mission achieved many of its technology objectives during its flight to the Moon in early 1994 but, because of a software error, was unable to test the autonomous tracking of a cold target. The preliminary analyses of the returned lunar data suggest that valuable scientific measurements were made on several important topics but that COMPLEX's highest-priority objectives for lunar science were not achieved. This is not surprising given that the rationale for Clementine was technological rather than scientific. COMPLEX lists below a few of the lessons that may be learned from Clementine. Although the Clementine mission was not conceived as a NASA science mission exactly like those planned for the Discovery program, many operational aspects of the two are similar. It is therefore worthwhile to understand the strengths and faults of the Clementine approach. Some elements of the Clementine operation that led to the mission's success include the following: (1) The mission's achievements were the responsibility of a single organization and its manager, which made that organization and that individual accountable for the final outcome; (2) The sponsor adopted a hands-off approach and set a minimum number of reviews (three); (3) The sponsor accepted a reasonable amount of risk and allowed the project team to make the trade-offs necessary to minimize the mission's risks while still accomplishing all its primary objectives; and (4) The development schedule was brief and the agreed-on funding (and funding profile) was adhered to. Among the operational shortcomings of Clementine were the following: (1) An overly ambitious schedule and a slightly lean budget (meaning insufficient time for software development and testing, and leading ultimately to human exhaustion); and (2) No support for data calibration, reduction, and analysis. The principal lesson to be learned in this category is that any benefits from the constructive application of higher

  17. The Clementine Mission: Past, Present, and Future

    NASA Astrophysics Data System (ADS)

    Nozette, Stewart

    1995-01-01

    During the past decade the Department of Defense, and the Ballistic Missile Defense Organization, BMDO (formally the Strategic Defense Initiative Organization, SDIO) of the US Department of Defense (DoD) have invested heavily in space technology, focused on the development of lighter more cost effective components and systems. With the end of the Cold War many of these technologies can be made available to the civilian community. To further these efforts in dual-use application, BMDO and NASA have collaborated on the Clementine mission. The Clementine spacecraft was launched on 25 January 1994 as a test of many of the most advanced lightweight technologies ever developed by the DoD. Clementine is currently in lunar orbit performing the lunar mapping phase of its mission. The mission has been integrated by a Naval Research Laboratory government/industry team in less than two years. The spacecraft itself has a dry weight of about 227 kg made possible by using very lightweight components. The sensor suite, provided by a Lawrence Livermore National Laboratory/industry team consists of two star tracker cameras, an ultraviolet-visible camera, a short wave infrared camera, a long wave infrared camera, and LIDAR, weighs less than 8 kg and covers the wavelength range from 0.3 to 9.5 microns. Additional lightweight technologies (inertial measurement units, reaction wheels, batteries, computing systems, and solid state recorders) have also been incorporated in the basic system design. On 3 May, 1994 the spacecraft will leave lunar orbit. Following an additional 2 Earth flybys, and a lunar flyby, the spacecraft will then execute a flyby of the the near-Earth-asteroid 1620 Geographos, around 31 August 1994. An extended mission to flyby near-Earth asteroid 1983 RD in October of 1995 is currently under study. A great deal of significant information will be returned by Clementine during its two months in lunar orbit. The data (which would fill a small library of compact discs

  18. 77 FR 63311 - Lake Clementine Hydro, LLC; Notice of Successive Preliminary Permit Application Accepted for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-16

    ... Energy Regulatory Commission Lake Clementine Hydro, LLC; Notice of Successive Preliminary Permit... October 2, 2012, Lake Clementine Hydro, LLC (Lake Clementine Hydro) filed an application for a successive preliminary permit, pursuant to section 4(f) of the Federal Power Act (FPA). Lake Clementine Hydro proposes...

  19. 75 FR 81942 - Importation of Clementines From Spain; Amendment to Inspection Provisions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ... of Clementines From Spain; Amendment to Inspection Provisions AGENCY: Animal and Plant Health... the importation of clementines from Spain by removing from the regulations the number of clementines... regulations the number of clementines per consignment from Spain to be sampled, APHIS would have...

  20. Stellar compass for the Clementine Mission

    SciTech Connect

    Wilson, B.

    1994-11-15

    A CCD sensor with 42 x 28 degrees FOV and 576 x 384 pixels was built by the Advanced Technology Program (ATP) in the Physics Department at LLNL. That sensor, called the StarTracker camera, is used on the Clementine Lunar Mapping mission between January and May, 1994. Together with the Stellar Compass software, the StarTracker camera provided a way of identifying its orientation to within about 150 microradians in camera body pitch and yaw. This presentation will be an overview of basically how the Stellar Compass software works, along with showing some of its performance results.

  1. Clementine High Resolution Camera Mosaicking Project

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This report constitutes the final report for NASA Contract NASW-5054. This project processed Clementine I high resolution images of the Moon, mosaicked these images together, and created a 22-disk set of compact disk read-only memory (CD-ROM) volumes. The mosaics were produced through semi-automated registration and calibration of the high resolution (HiRes) camera's data against the geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic produced by the US Geological Survey (USGS). The HiRes mosaics were compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution nadir-looking observations. The images were spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel for sub-polar mosaics (below 80 deg. latitude) and using the stereographic projection at a scale of 30 m/pixel for polar mosaics. Only images with emission angles less than approximately 50 were used. Images from non-mapping cross-track slews, which tended to have large SPICE errors, were generally omitted. The locations of the resulting image population were found to be offset from the UV/Vis basemap by up to 13 km (0.4 deg.). Geometric control was taken from the 100 m/pixel global and 150 m/pixel polar USGS Clementine Basemap Mosaics compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Radiometric calibration was achieved by removing the image nonuniformity dominated by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap, that approximately transform the 8-bit HiRes data to photometric units. The sub-polar mosaics are divided into tiles that cover approximately 1.75 deg. of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. Polar mosaics are tiled into squares 2250 pixels on a

  2. Clementine High Resolution Camera Mosaicking Project

    NASA Astrophysics Data System (ADS)

    1998-10-01

    This report constitutes the final report for NASA Contract NASW-5054. This project processed Clementine I high resolution images of the Moon, mosaicked these images together, and created a 22-disk set of compact disk read-only memory (CD-ROM) volumes. The mosaics were produced through semi-automated registration and calibration of the high resolution (HiRes) camera's data against the geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic produced by the US Geological Survey (USGS). The HiRes mosaics were compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution nadir-looking observations. The images were spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel for sub-polar mosaics (below 80 deg. latitude) and using the stereographic projection at a scale of 30 m/pixel for polar mosaics. Only images with emission angles less than approximately 50 were used. Images from non-mapping cross-track slews, which tended to have large SPICE errors, were generally omitted. The locations of the resulting image population were found to be offset from the UV/Vis basemap by up to 13 km (0.4 deg.). Geometric control was taken from the 100 m/pixel global and 150 m/pixel polar USGS Clementine Basemap Mosaics compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Radiometric calibration was achieved by removing the image nonuniformity dominated by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap, that approximately transform the 8-bit HiRes data to photometric units. The sub-polar mosaics are divided into tiles that cover approximately 1.75 deg. of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. Polar mosaics are tiled into squares 2250 pixels on a

  3. Multispectral Mapping of the Moon by Clementine

    NASA Technical Reports Server (NTRS)

    Eliason, Eric M.; McEwen, Alfred S.; Robinson, M.; Lucey, Paul G.; Duxbury, T.; Malaret, E.; Pieters, Carle; Becker, T.; Isbell, C.; Lee, E.

    1998-01-01

    One of the chief scientific objectives of the Clementine mission at the Moon was to acquire global multispectral mapping. A global digital map of the Moon in 11 spectral bandpasses and at a scale of 100 m/pixel is being produced at the U.S. Geological Survey in Flagstaff Arizona Near-global coverage was acquired with the UVVIS camera (central wavelengths of 415, 750, 900, 950, and 1000 nm) and the NIR camera (1102, 1248, 1499, 1996, 2620, and 2792 nary). We expect to complete processing of the UVVIS mosaics before the fall of 1998, and to complete the NIR mosaics a year later. The purpose of this poster is to provide an update on the processing and to show examples of the products or perhaps even a wall-sized display of color products from the UVVIS mosaics.

  4. Charged-particle telescope experiment on Clementine.

    PubMed

    Baker, D N; Kanekal, S; Blake, J B; Adams, J H

    1995-01-01

    The charged-particle telescope (CPT) onboard the Clementine spacecraft measured the fluxes of energetic protons emitted in solar energetic particle events. Protons in the energy range from 10 to 80 MeV were of greatest interest for radiation effects such as total dose and single event upsets. Energetic electrons were also of interest for spacecraft charging and their contribution to total dose. The lower-energy CPT electron channels (25-500 keV) were mainly of geophysical interest. While orbiting the moon, the CPT observed the wake created by the moon when it blocked the flow of energetic particles in the magnetotail region. The CPT provided opportunities to observe energetic electron bursts during magnetic storms and magnetospheric substorms. CPT data are particularly useful in multispacecraft studies of interplanetary disturbances and their interaction with the magnetosphere. The proton channels on the CPT provided data on solar energetic protons and storm-time protons associated with the passage of an interplanetary shock at 0903 UT on Feb. 21, 1994. Results are compared with those from GOES-7, SAMPEX, and GEOTAIL.

  5. Mapping of the Moon by Clementine

    USGS Publications Warehouse

    McEwen, A.S.; Robinson, M.S.

    1997-01-01

    The "faster, cheaper, better" Clementine spacecraft mission mapped the Moon from February 19 to May 3, 1994. Global coverage was acquired in 11 spectral bandpasses from 415 to 2792 nm and at resolutions of 80-330 m/pixel; a thermal-infrared camera sampled ???20% of the surface; a high-resolution camera sampled selected areas (especially the polar regions); and a lidar altimeter mapped the large-scale topography up to latitudes of ??75??. The spacecraft was in a polar, elliptical orbit, 400-450 km periselene altitude. Periselene latitude was -28.5?? for the first month of mapping, then moved to +28.5??. NASA is supporting the archiving, systematic processing, and analysis of the ???1.8 million lunar images and other datasets. A new global positional network has been constructed from 43,000 images and ???0.5 million match points; new digital maps will facilitate future lunar exploration. In-flight calibrations now enable photometry to a high level of precision for the uv-visible CCD camera. Early science results include: (1) global models of topography, gravity, and crustal thicknesses; (2) new information on the topography and structure of multiring impact basins; (3) evidence suggestive of water ice in large permanent shadows near the south pole; (4) global mapping of iron abundances; and (5) new constraints on the Phanerozoic cratering rate of the Earth. Many additional results are expected following completion of calibration and systematic processing efforts. ?? 1997 COSPAR. Published by Elsevier Science Ltd.

  6. Authenticity of PGI "Clementine of Calabria" by multielement fingerprint.

    PubMed

    Benabdelkamel, Hicham; Di Donna, Leonardo; Mazzotti, Fabio; Naccarato, Attilio; Sindona, Giovanni; Tagarelli, Antonio; Taverna, Domenico

    2012-04-11

    Clementine is a citrus fruit that has found a peculiar habitat in specific areas of Calabria, a region located in southern Italy. Due to its peculiar characteristics it was recently awarded with protected geographical indications (PGI) from the European Union. In this work, stepwise linear discriminant analysis (S-LDA), soft independent modeling of class analogy (SIMCA), and partial least-squares discriminant analysis (PLS-DA) were used to build chemometric models able to protect PGI Clementine from others of different origin. Accordingly, the concentration of 24-26 elements was determined in peel and juice samples, respectively, obtained from Calabrian PGI clementine and from fruits cultivated in Algeria, Tunisia, and Spain. A cross-validation procedure has shown very satisfactory values of prediction ability for both S-LDA (96.6% for juice samples and 100% for peel samples) and SIMCA (100% for both peel and juice samples). PLS-DA models also yielded satisfactory results.

  7. The Clementine Mission science return at the Moon and Geographos

    NASA Technical Reports Server (NTRS)

    Vorderbruegge, R. W.; Davies, M. E.; Horan, D. M.; Lucey, P. G.; Pieters, C. M.; Mcewen, A. S.; Nozette, S.; Shoemaker, E. M.; Squyres, S. W.; Thomas, P. C.

    1993-01-01

    The Clementine Mission is being built and flown by the Naval Research Laboratory under the sponsorship of the Strategic Defense Initiative Organization of the United States Department of Defense in joint-cooperation with NASA, and will explore the Moon and the near-Earth asteroid (NEA) 1620 Geographos with lightweight sensors developed by the Lawrence Livermore National Laboratory. A NASA Science Team for this mission will be selected by way of a NRA in April 1993. The instrument suite includes imaging cameras that cover a spectral range from the near-ultraviolet to the mid-infrared, a laser ranger, and, potentially, a charged particle telescope. To be launched in early 1994, Clementine will be in lunar orbit from February through May 1994, at which time it will depart the Moon for a flyby of 1620 Geographos in August 1994. This mission represents an outstanding opportunity for scientists interested in the Moon and asteroids. It is anticipated that the data returned from this mission will permit: an assessment of global lunar crustal heterogeneity and a resolution of less than 1 km; an assessment of the lithologic heterogeneity of Geographos at a scale of 100 m or better; and an assessment of surface processes on Geographos on the order of 10 m. The basic mission of Clementine and some of the key scientific questions that will be addressed are described. Additional material on the Clementine mission, its data handling and processing, and its instrument suite is presented elsewhere.

  8. Systematic Processing of Clementine Data for Scientific Analyses

    NASA Technical Reports Server (NTRS)

    Mcewen, A. S.

    1993-01-01

    If fully successful, the Clementine mission will return about 3,000,000 lunar images and more than 5000 images of Geographos. Effective scientific analyses of such large datasets require systematic processing efforts. Concepts for two such efforts are described: glogal multispectral imaging of the moon; and videos of Geographos.

  9. 7 CFR 319.56-34 - Clementines from Spain.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... export to the United States, prior to cold treatment, inspectors will cut and inspect 200 fruit that are... program for the remainder of that shipping season. (g) Cold treatment. Clementines must be cold treated in... States, inspectors will examine the cold treatment data for each consignment to ensure that the...

  10. Clementine Observes the Moon, Solar Corona, and Venus

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In 1994, during its flight, the Clementine spacecraft returned images of the Moon. In addition to the geologic mapping cameras, the Clementine spacecraft also carried two Star Tracker cameras for navigation. These lightweight (0.3 kg) cameras kept the spacecraft on track by constantly observing the positions of stars, reminiscent of the age-old seafaring tradition of sextant/star navigation. These navigation cameras were also to take some spectacular wide angle images of the Moon.

    In this picture the Moon is seen illuminated solely by light reflected from the Earth--Earthshine! The bright glow on the lunar horizon is caused by light from the solar corona; the sun is just behind the lunar limb. Caught in this image is the planet Venus at the top of the frame.

  11. UV/visible camera for the Clementine mission

    SciTech Connect

    Kordas, J.F.; Lewis, I.T.; Priest, R.E.

    1995-04-01

    This article describes the Clementine UV/Visible (UV/Vis) multispectral camera, discusses design goals and preliminary estimates of on-orbit performance, and summarizes lessons learned in building and using the sensor. While the primary objective of the Clementine Program was to qualify a suite of 6 light-weight, low power imagers for future Department of Defense flights, the mission also has provided the first systematic mapping of the complete lunar surface in the visible and near-infrared spectral regions. The 410 g, 4.65 W UV/Vis camera uses a 384 x 288 frame-transfer silicon CCD FPA and operates at 6 user-selectable wavelength bands between 0.4 and 1.1 {micro}m. It has yielded lunar imagery and mineralogy data with up to 120 in spatial resolution (band dependent) at 400 km periselene along a 39 km cross-track swath.

  12. Clementine: Anticipated scientific datasets from the Moon and Geographos

    NASA Technical Reports Server (NTRS)

    Mcewen, A. S.

    1993-01-01

    The Clementine spacecraft mission is designed to test the performance of new lightweight and low-power detectors developed at the Lawrence Livermore National Laboratory (LLNL) for the Strategic Defense Initiative Office (SDIO). A secondary objective of the mission is to acquire useful scientific data, principally of the Moon and the near-Earth asteroid Geographos. The spacecraft will be in an elliptical polar orbit about the Moon for about 2 months beginning in February of 1994 and it will fly by Geographos on August 31. Clementine will carry seven detectors each weighing less than about 1 kg: two Star Trackers wide-angle uv/vis wide-angle Short Wavelength IR (SWIR) Long-Wavelength IR (LWIR) and LIDAR (Laser Image Detection And Ranging) narrow-angle imaging and ranging. Additional presentations about the mission detectors and related science issues are in this volume. If fully successful Clementine will return about 3 million lunar images, a dataset with nearly as many bits of data (uncompressed) as the first cycle of Magellan and more than 5000 images of Geographos. The complete and efficient analysis of such large data sets requires systematic processing efforts. Described below are concepts for two such efforts for the Clementine mission: global multispectral imaging of the Moon and videos of the Geographos flyby. Other anticipated datasets for which systematic processing might be desirable include multispectral observations of Earth; LIDAR altimetry of the Moon with high-resolution imaging along each ground track; high-resolution LIDAR color along each lunar ground track which could be used to identify potential titanium-rich deposits at scales of a few meters; and thermal IR imaging along each lunar ground track (including nighttime observations near the poles).

  13. Clementine: An inexpensive mission to the Moon and Geographos

    NASA Technical Reports Server (NTRS)

    Shoemaker, Eugene M.; Nozette, Stewart

    1993-01-01

    The Clementine Mission, a joint project of the Strategic Defense Initiative Organization (SDIO) and NASA, has been planned primarily to test and demonstrate a suite of lightweight sensors and other lightweight spacecraft components under extended exposure to the space environment. Although the primary objective of the mission is to space-qualify sensors for Department of Defense applications, it was recognized in 1990 that such a mission might also be designed to acquire scientific observations of the Moon and of Apollo asteroid (1620) Geographos. This possibility was explored jointly by SDIO and NASA, including representatives from NASA's Discovery Program Science Working Group, in early 1991. Besides the direct return of scientific information, one of the benefits envisioned from a joint venture was the development of lightweight components for possible future use in NASA's Discovery-class spacecraft. In Jan. 1992, SDIO informed NASA of its intent to fly a 'Deep Space Program Science Experiment,' now popularly called Clementine; NASA then formed an advisory science working group to assist in the early development of the mission. The Clementine spacecraft is being assembled at the Naval Research Laboratory, which is also in charge of the overall mission design and mission operations. Support for mission design is being provided by GSFC and by JPL. NASA's Deep Space Network will be utilized in tracking and communicating with the spacecraft. Following a recommendation of the COMPLEX committee of the Space Science Board, NASA will issue an NRA and appoint a formal science team in early 1993. Clementine is a 3-axis stabilized, 200 kg (dry weight) spacecraft that will be launched on a refurbished Titan-2G. One of the goals has been to build two spacecraft, including the sensors, for $100M. Total time elapsed from the decision to proceed to the launch will be two years.

  14. 77 FR 22463 - Importation of Clementines From Spain; Amendment to Inspection Provisions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-16

    ..., 2010, we published in the Federal Register (75 FR 81942-81943, Docket No. APHIS-2010-0036) a proposal... Inspection Service 7 CFR Part 319 RIN 0579-AD27 Importation of Clementines From Spain; Amendment to...: We are amending the regulations governing the importation of clementines from Spain by removing...

  15. System level mechanical testing of the Clementine spacecraft

    NASA Technical Reports Server (NTRS)

    Haughton, James; Hauser, Joseph; Raynor, William; Lynn, Peter

    1994-01-01

    This paper discusses the system level structural testing that was performed to qualify the Clementine Spacecraft for flight. These tests included spin balance, combined acoustic and axial random vibration, lateral random vibration, quasi-static loads, pyrotechnic shock, modal survey and on-orbit jitter simulation. Some innovative aspects of this effort were: the simultaneously combined acoustic and random vibration test; the mass loaded interface modal survey test; and the techniques used to assess how operating on board mechanisms and thrusters affect sensor vision.

  16. Efficacy of Neoseiulus californicus and Phytoseiulus persimilis in suppression of Tetranychus urticae in young clementine plants.

    PubMed

    Abad-Moyano, Raquel; Pina, Tatiana; Pérez-Panadés, Jordi; Carbonell, Emilio A; Urbaneja, Alberto

    2010-04-01

    Tetranychus urticae is one of the most damaging tetranychid mites affecting clementine orchards in Spain, where natural control is insufficient. Furthermore, in clementine nurseries, tender foliage is highly susceptible to attack and natural enemies are almost always absent. Therefore, acaricides are often used indiscriminately. Alternative control measures are necessary, both in commercial orchards and clementine nurseries. In order to assess the efficacy of inoculative releases of N. californicus and P. persimilis to reduce T. urticae populations in young Spanish clementine plants, a semi-field experiment was conducted and repeated in three seasons (spring, summer and autumn). Phytoseiulus persimilis was highly effective in reducing both T. urticae infestations and the damage level inflicted on plants at both release rates evaluated (40 and 80 phytoseiids/plant) and all three periods considered. By contrast, N. californicus demonstrated low performance under certain conditions. The results of this study could be adapted and transferred to nurseries and young citrus plantations.

  17. A sharper view of impact craters from clementine data.

    PubMed

    Pieters, C M; Staid, M I; Fischer, E M; Tompkins, S; He, G

    1994-12-16

    The ultraviolet-visible camera on the Clementine spacecraft obtained high-spatial resolution images of the moon in five spectral channels. Impact craters mapped with these multispectral images show a scale of lithologic diversity that varies with crater size and target stratigraphy. Prominent lithologic variations (feldspathic versus basaltic) occur within the south wall of Copernicus (93 kilometers in diameter) on the scale of 1 to 2 kilometers. Lithologic diversity at Tycho (85 kilometers in diameter) is less apparent at this scale, although the impact melt of these two large craters is remarkably similar in this spectral range. The lunar surface within and around the smaller crater Giordano Bruno (22 kilometers in diameter) is largely dominated by the mixing of freshly excavated material with surrounding older soils derived from a generally similar feldspathic lithology.

  18. Cotyledonal chloroplasts in the hypogeal seeds of clementine.

    PubMed

    Casadoro, G; Rascio, N

    1987-03-01

    Clementine (Citrus nobilisxCitrus aurantium amara pumila) is a chloroembryophyte with green quiescent embryos and hypogeal germination. The cotyledonal chloroplasts have been studied during germination in the dark and under two different irradiances 120 and 240 μmol·m(-2)·s(-1) throughout a period of three weeks. The plastids of the outer adaxial and inner regions develop differently. In the light, the former differentiate a photosynthetically active thylakoid system with an ultrastructural organization and a polypeptide composition resembling that of leaf chloroplasts. The "inner" chloroplasts maintain an organization reminiscent of chloroplasts of the quiescent embryo and never get beyond the photosynthesis/respiration compensation point; their differentiation pattern appears essentially the same under the two different irradiances. These observations and the germination in the dark indicate that the above differentiation is not strictly photodependent. The greening ability of the cotyledons provides, on occasion, an additional photosynthetic supply to this plant.

  19. From cancer to cookbooks: the story of Clementine Paddleford.

    PubMed

    Shuman, Andrew G

    2013-02-01

    Clementine Paddleford overcame laryngeal cancer to become the most famous culinary journalist of her time. Through archival research, her long-forgotten tale may be shared anew. Perhaps no individual better encapsulates the consequences of head and neck cancer than does a food reporter, for whom speech and swallowing are truly indispensable. In an era in which vocal rehabilitation after total laryngectomy was limited, and when conservation procedures were still being developed, Paddleford underwent partial laryngectomy in 1931. Thereafter, her tracheotomy morphed into a fashion statement, and her dysphonia became her calling card, as she traveled the world in pursuit of original recipes and the stories behind them. Paddleford reminds us that cancer survivorship is not simply measured in months or years. Her legacy is a testament to both individual willpower and the ability of doctors and patients to balance risks and benefits in pursuit of partnerships with common goals.

  20. The clementine mission to the moon: scientific overview.

    PubMed

    Nozette, S; Rustan, P; Pleasance, L P; Kordas, J F; Lewis, I T; Park, H S; Priest, R E; Horan, D M; Regeon, P; Lichtenberg, C L; Shoemaker, E M; Eliason, E M; McEwen, A S; Robinson, M S; Spudis, P D; Acton, C H; Buratti, B J; Duxbury, T C; Baker, D N; Jakosky, B M; Blamont, J E; Corson, M P; Resnick, J H; Rollins, C J; Davies, M E; Lucey, P G; Malaret, E; Massie, M A; Pieters, C M; Reisse, R A; Simpson, R A; Smith, D E; Sorenson, T C; Breugge, R W; Zuber, M T

    1994-12-16

    In the course of 71 days in lunar orbit, from 19 February to 3 May 1994, the Clementine spacecraft acquired just under two million digital images of the moon at visible and infrared wavelengths. These data are enabling the global mapping of the rock types of the lunar crust and the first detailed investigation of the geology of the lunar polar regions and the lunar far side. In addition, laser-ranging measurements provided the first view of the global topographic figure of the moon. The topography of many ancient impact basins has been measured, and a global map of the thickness of the lunar crust has been derived from the topography and gravity.

  1. Mineralogy of the last lunar basalts: Results from Clementine

    USGS Publications Warehouse

    Staid, M.I.; Pieters, C.M.

    2001-01-01

    The last major phase of lunar volcanism produced extensive high-titanium mare deposits on the western nearside which remain unsampled by landing missions. The visible and near-infrared reflectance properties of these basalts are examined using Clementine multispectral images to better constrain their mineralogy. A much stronger 1 ??m ferrous absorption was observed for the western high-titanium basalts than within earlier maria, suggesting that these last major mare eruptions also may have been the most iron-rich. These western basalts also have a distinctly long-wavelength, 1 ??m ferrous absorption which was found to be similar for both surface soils and materials excavated from depth, supporting the interpretation of abundant olivine within these deposits. Spectral variation along flows within the Imbrium basin also suggests variations in ilmenite content along previously mapped lava flows as well as increasing olivine content within subsequent eruptions. Copyright 2001 by the American Geophysical Union.

  2. Clementine observations of the Aristarchus region of the moon

    USGS Publications Warehouse

    McEwen, A.S.; Robinson, M.S.; Eliason, E.M.; Lucey, P.G.; Duxbury, T.C.; Spudis, P.D.

    1994-01-01

    Multispectral and topographic data acquired by the Clementine spacecraft provide information on the composition and geologic history of the Aristarchus region of the moon. Altimetry profiles show the Aristarchus plateau dipping about 1?? to the north-northwest and rising about 2 kilometers above the surrounding lavas of Oceanus Procellarum to the south. Dark, reddish pyroclastic glass covers the plateau to average depths of 10 to 30 meters, as determined from the estimated excavation depths of 100- to 1000-meter-diameter craters that have exposed materials below the pyroclastics. These craters and the wall of sinuous rilles also show that mare basalts underlie the pyroclastics across much of the plateau. Near-infrared images of Aristarchus crater reveal oilvine-rich materials and two kilometer-sized outcrops of anorthosite in the central peaks. The anorthosite could be either a derivative of local magnesium-suite magmatism or a remnant of the ferroan anorthosite crust that formed over the primordial magma ocean.

  3. Radiation effects in space: The Clementine I mission

    SciTech Connect

    Guzik, T. G.; Clayton, E.; Wefel, J. P.

    1994-12-20

    The space radiation environment for the CLEMENTINE I mission was investigated using a new calculational model, CHIME, which includes the effects of galactic cosmic rays (GCR), anomalous component (AC) species and solar energetic particle (SEP) events and their variations as a function of time. Unlike most previous radiation environment models, CHIME is based upon physical theory and is {open_quotes}calibrated{close_quotes} with energetic particle measurements made over the last two decades. Thus, CHIME provides an advance in the accuracy of estimating the interplanetary radiation environment. Using this model we have calculated particle energy spectra, fluences and linear energy transfer (LET) spectra for all three major components of the CLEMENTINE I mission during 1994: (1) the spacecraft in lunar orbit, (2) the spacecraft during asteroid flyby, and (3) the interstate adapter USA in Earth orbit. Our investigations indicate that during 1994 the level of solar modulation, which dominates the variation in the GCR and AC flux as a function of time, will be decreasing toward solar minimum levels. Consequently the GCR and AC flux will be increasing during Y, the year and, potentially, will rise to levels seen during previous solar minimums. The estimated radiation environment also indicates that the AC will dominate the energetic particle spectra for energies below 30-50 MeV/nucleon, while the GCR have a peak flux at {approximately}300 MeV/nucleon and maintain a relatively high flux level up to >1000 MeV/nucleon. The AC significantly enhances the integrated flux for LET in the range 1 to 10 MeV/(mg/cm{sup 2}), but due to the steep energy spectra of the AC a relatively small amount of material ({approximately}50 mils of Al) can effectively shield against this component. The GCR are seen to be highly penetrating and require massive amounts of shielding before there is any appreciable decrease in the LET flux.

  4. Radiation effects in space: The Clementine 1 mission

    NASA Astrophysics Data System (ADS)

    Guzik, T. Gregory; Clayton, Edmund; Wefel, John P.

    1994-12-01

    The space radiation environment for the Clementine 1 mission was investigated using a new calculational model, CHIME, which includes the effects of galactic cosmic rays (GCR), anomalous component (AC) species and solar energetic particle (SEP) events and their variations as a function of time. Unlike most previous radiation environment models, CHIME is based upon physical theory and is 'calibrated' with energetic particle measurements made over the last two decades. Thus, CHIME provides an advance in the accuracy of estimating the interplanetary radiation environment. Using this model we have calculated particle energy spectra, fluences and linear energy transfer (LET) spectra for all three major components of the Clementine 1 mission during 1994: (1) the spacecraft in lunar orbit, (2) the spacecraft during asteroid flyby, and (3) the interstage adapter (ISA) in earth orbit. Our investigations indicate that during 1994 the level of solar modulation, which dominates the variation in the GCR and AC flux as a function of time, will be decreasing toward solar minimum levels. Consequently the GCR and AC flux will be increasing during the year and, potentially, will rise to levels seen during previous solar minimums. The estimated radiation environment also indicates that the AC will dominate the energetic particle spectra for energies below 30-50 MeV/nucleon, while the GCR have a peak flux at approximately 300 MeV/nucleon and maintain a relatively high flux level up to greater than 1000 MeV/nucleon. The AC significantly enhances the integrated flux for LET in the range 1 to 10 MeV/(mg/sq cm), but due to the steep energy spectra of the AC a relatively small amount of material (approximately 50 mils of Al) can effectively shield against this component. The GCR are seen to be highly penetrating and require massive amounts of shielding before there is any appreciable decrease in the LET flux.

  5. SMART-1/Clementine study of Humorum and Procellarum Basins

    NASA Astrophysics Data System (ADS)

    Peters, Stefan

    We have combined SMART-1 AMIE camera images with Clementine UV/VIS data for two end-member lunar basins (circular - Mare Humorum and irregular - Oceanus Procellarum), to determine the coupling between basin origin, tectonics and volcanism. For Humorum, fault structures that include graben and strike-slip faults were mapped using ARC-GIS. Resulting tectonic maps agree well with an idealized model for mascon tectonics (Melosh 1978). This is in agreement with observed Bouguer anomalies. For Procellarum, there is no excess gravity and tectonic deformation does not agree with the Melosh model. We observed radial distribution of mare ridges in Humorum (1) and the presence of mare ridges without mascon tectonics in Procellarum (2), wherefor the origin of mare ridges in these areas cannot be related to mascons. To study impact related volcanic processes, craters with diameter ¡100 km were mapped and classified as volcanically flooded or unflooded. Our results suggest a mechanism in which craters were flooded related to large scale mare volcanic activity in the same or nearby area of the crater. We propose that this melt migrated to the specific craters through impact fractures. We used the Advanced Moon micro-Imager Experiment (AMIE) on ESA SMART-1 Moon mission, average pixel resolution of 80m. We also used UV/VIS pictures (multi-spectral images assessing the surface mineralogy of the Moon) and gravity maps derived after Clementine Moon mission (gravitational anomalies and crustal thickness maps). Ongoing research is taking place on the global structure and geochemical units of the South Pole-Aitken basin.

  6. Newer views of the Moon: Comparing spectra from Clementine and the Moon Mineralogy Mapper

    USGS Publications Warehouse

    Kramer, G.Y.; Besse, S.; Nettles, J.; Combe, J.-P.; Clark, R.N.; Pieters, C.M.; Staid, M.; Malaret, E.; Boardman, J.; Green, R.O.; Head, J.W.; McCord, T.B.

    2011-01-01

    The Moon Mineralogy Mapper (M3) provided the first global hyperspectral data of the lunar surface in 85 bands from 460 to 2980 nm. The Clementine mission provided the first global multispectral maps the lunar surface in 11 spectral bands across the ultraviolet-visible (UV-VIS) and near-infrared (NIR). In an effort to understand how M3 improves our ability to analyze and interpret lunar data, we compare M3 spectra with those from Clementine's UV-VIS and NIR cameras. The Clementine mission provided the first global multispectral maps the lunar surface in 11 spectral bands across the UV-VIS and NIR. We have found that M3 reflectance values are lower across all wavelengths compared with albedos from both of Clementine's UV-VIS and NIR cameras. M3 spectra show the Moon to be redder, that is, have a steeper continuum slope, than indicated by Clementine. The 1 m absorption band depths may be comparable between the instruments, but Clementine data consistently exhibit shallower 2 m band depths than M 3. Absorption band minimums are difficult to compare due to the significantly different spectral resolutions. Copyright 2011 by the American Geophysical Union.

  7. Lunar South Pole Topography Derived from Clementine Imagery

    NASA Astrophysics Data System (ADS)

    Rosiek, M. R.; Kirk, R.; Howington-Kraus, A.

    1999-01-01

    During the Clementine Mission both oblique and vertical multispectral images were collected. The oblique and vertical images from a single spectral band collected during the same orbit form a stereo pair that can be used to derive the topography. These stereo pairs are being used to derive the topography of an area (90 deg S to 650S latitude) surrounding the lunar south pole. Work on the lunar north pole topography will start after completion of the south pole topography. This report provides an update on the initial results for the lunar south pole topography. In 1994, the Clementine spacecraft acquired digital images of the Moon at visible and near-infrared wavelengths. Onboard there were four camera systems and a laser altimeter. During the first pass, periapsis was at 30S and the highest resolution images were obtained in the southern hemisphere. Over the northern polar area, a series of oblique and vertical images were obtained with the ultraviolet-visible (UV-VIS) camera on each orbit. During the second pass, periapsis was at 30N and the image acquisition strategy was reversed. The UV-VIS camera image size was 384 x 288 pixels with five spectral bands and one broad band. The 750-nm-band stereo pairs are the primary image source for this study. The ground sample distances (GSD) for oblique images range from 300 to 400m. The GSD for the vertical images, acquired at the end of an orbit, are slightly larger and range from 325 to 450 m. Using the formula for stereo-height accuracy, an estimate of height accuracy is 180m. This formula is IFOVMAX)/(K*B/H with IFOVMAX defined as Maximum Instantaneous Field of View; B/H is the base-to-height ratio and K is an estimate of pixel measurement accuracy on the imagery. The Clementine laser altimeter (LIDAR) data were used previously to produce a global topographic model of the Moon . The model has a vertical accuracy of about 100 m and a spatial resolution of 2.5 deg. Altimetry data were collected between 79S and 810N

  8. Topography of the Moon from the Clementine Lidar

    NASA Technical Reports Server (NTRS)

    Smith, David E.; Zuber, Maria T.; Neumann, Gregory A.; Lemoine, Frank G.

    1997-01-01

    Range measurements from the lidar instrument carried aboard the Clementine spacecraft have been used to produce an accurate global topographic model of the Moon. This paper discusses the function of the lidar; the acquisition, processing, and filtering of observations to produce a global topographic model; and the determination of parameters that define the fundamental shape of the Moon. Our topographic model: a 72nd degree and order spherical harmonic expansion of lunar radii, is designated Goddard Lunar Topography Model 2 (GLTM 2). This topographic field has an absolute vertical accuracy of approximately 100 m and a spatial resolution of 2.5 deg. The field shows that the Moon can be described as a sphere with maximum positive and negative deviations of approx. 8 km, both occurring on the farside, in the areas of the Korolev and South Pole-Aitken (S.P.-Aitken) basins. The amplitude spectrum of the topography shows more power at longer wavelengths as compared to previous models, owing to more complete sampling of the surface, particularly the farside. A comparison of elevations derived from the Clementine lidar to control point elevations from the Apollo laser altimeters indicates that measured relative topographic heights generally agree to within approx. 200 in over the maria. While the major axis of the lunar gravity field is aligned in the Earth-Moon direction, the major axis of topography is displaced from this line by approximately 10 deg to the cast and intersects the farside 24 deg north of the equator. The magnitude of impact basin topography is greater than the lunar flattening (approx. 2 km) and equatorial ellipticity (approx. 800 m), which imposes a significant challenge to interpreting the lunar figure. The floors of mare basins are shown to lie close to an equipotential surface, while the floors of unflooded large basins, except for S.P.-Aitken, lie above this equipotential. The radii of basin floors are thus consistent with a hydrostatic mechanism

  9. Clementine observations of the aristarchus region of the moon.

    PubMed

    McEwen, A S; Robinson, M S; Eliason, E M; Lucey, P G; Duxbury, T C; Spudis, P D

    1994-12-16

    Multispectral and topographic data acquired by the Clementine spacecraft provide information on the composition and geologic history of the Aristarchus region of the moon. Altimetry profiles show the Aristarchus plateau dipping about 1 degrees to the north-northwest and rising about 2 kilometers above the surrounding lavas of Oceanus Procellarum to the south. Dark, reddish pyroclastic glass covers the plateau to average depths of 10 to 30 meters, as determined from the estimated excavation depths of 100- to 1000-meter-diameter craters that have exposed materials below the pyroclastics. These craters and the walls of sinuous rilles also show that mare basalts underlie the pyroclastics across much of the plateau. Near-infrared images of Aristarchus crater reveal olivine-rich materials and two kilometer-sized outcrops of anorthosite in the central peaks. The anorthosite could be either a derivative of local magnesium-suite magmatism or a remnant of the ferroan anorthosite crust that formed over the primordial magma ocean. PMID:17737082

  10. Lunar Crustal Modeling of Mare Orientale from Clementine Satellite Observations

    NASA Astrophysics Data System (ADS)

    von Frese, R. R. B.; Tan, L.; Potts, L. V.; Merry, C. J.; Bossler, J. D.

    1996-03-01

    Clementine satellite gravity and altimetry observations were analyzed in lunar spherical coordinates for density variations that may be related to the crustal features and evolution of Mare Orientale. The analysis considered 2-degree gridded free-air gravity anomaly and LIDAR topographic estimates for a 68-degree by 68-degree region of the moon centered roughly on Mare Orientale. At this scale of coverage, the gravity anomalies appear to be dominated almost completely by crustal density variations related to surface topography, crustal isostasy, mantle topography, and meteorite impact. The topography of the study region includes over 11 km of relief, the gravity effect of which we modeled in lunar spherical coordinates by Gauss-Legendre quadrature integration assuming a topographic density of 2.8 g/cc. We observed substantial positive and negative correlations between the free-air and topographic gravity anomalies that seriously limit the utility of simple Bouguer gravity anomalies for lunar subsurface studies. Using the wavenumber correlation spectrum between the free-air and topographic gravity anomalies, we designed correlation filters to extract the the correlative anomalies in the two data sets.

  11. Automated identification of basalt spectra in Clementine lunar data

    NASA Astrophysics Data System (ADS)

    Antonenko, I.; Osinski, G. R.

    2011-06-01

    The identification of fresh basalt spectra plays an important role in lunar stratigraphic studies; however, the process can be time consuming and labor intensive. Thus motivated, we developed an empirically derived algorithm for the automated identification of fresh basalt spectra from Clememtine UVVIS data. This algorithm has the following four parameters and limits: BC Ratio=3(R950-R900)/(R900-R750)<1.1, CD Delta=(R1000-R950)/R750-1.09(R950-R900)/R750>0.003 and <0.06, B Slope=(R900-R750)/(3R750)<-0.012, and Band Depth=(R750-R950)/(R750-R415)>0.1, where R750 represents the unnormalized reflectance of the 750 nm Clementine band, and so on. Algorithm results were found to be accurate to within an error of 4.5% with respect to visual classification, though olivine spectra may be under-represented. Overall, fresh basalts identified by the algorithm are consistent with expectations and previous work in the Mare Humorum area, though accuracy in other areas has not yet been tested. Great potential exists in using this algorithm for identifying craters that have excavated basalts, estimating the thickness of mare and cryptomare deposits, and other applications.

  12. Star tracker stellar compass for the Clementine mission

    SciTech Connect

    Kordas, J.F.; Lewis, I.T.; Wilson, B.A.

    1995-04-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star tracker stellar compasses (star tracker camera + stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 x 384 FPA and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 m{sub v}, providing rms pointing accuracy of better than 100 {micro}rad pitch and yaw and 450 {micro}rad roll. A description of this light-weight, low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights.

  13. Clementine observations of the aristarchus region of the moon.

    PubMed

    McEwen, A S; Robinson, M S; Eliason, E M; Lucey, P G; Duxbury, T C; Spudis, P D

    1994-12-16

    Multispectral and topographic data acquired by the Clementine spacecraft provide information on the composition and geologic history of the Aristarchus region of the moon. Altimetry profiles show the Aristarchus plateau dipping about 1 degrees to the north-northwest and rising about 2 kilometers above the surrounding lavas of Oceanus Procellarum to the south. Dark, reddish pyroclastic glass covers the plateau to average depths of 10 to 30 meters, as determined from the estimated excavation depths of 100- to 1000-meter-diameter craters that have exposed materials below the pyroclastics. These craters and the walls of sinuous rilles also show that mare basalts underlie the pyroclastics across much of the plateau. Near-infrared images of Aristarchus crater reveal olivine-rich materials and two kilometer-sized outcrops of anorthosite in the central peaks. The anorthosite could be either a derivative of local magnesium-suite magmatism or a remnant of the ferroan anorthosite crust that formed over the primordial magma ocean.

  14. Star tracker stellar compass for the Clementine mission

    NASA Astrophysics Data System (ADS)

    Kordas, Joseph F.; Lewis, Isabella T.; Wilson, Bruce A.; Nielsen, Darron P.; Park, Hye-Sook; Priest, Robert E.; Hills, Robert F.; Shannon, Michael J.; Ledebuhr, Arno G.; Pleasance, Lyn D.

    1995-06-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared region. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star tracker stellar compasses (star tracker camera + stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served as a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 X 384 FPA and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 mv, providing rms pointing accuracy of better than 100 (mu) rad pitch and yaw and 450 (mu) rad roll. A description of this light-weight, low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission's primary objective for flight qualifying the sensors for future Department of Defense flights.

  15. Asteroid approach covariance analysis for the Clementine mission

    NASA Technical Reports Server (NTRS)

    Ionasescu, Rodica; Sonnabend, David

    1993-01-01

    The Clementine mission is designed to test Strategic Defense Initiative Organization (SDIO) technology, the Brilliant Pebbles and Brilliant Eyes sensors, by mapping the moon surface and flying by the asteroid Geographos. The capability of two of the instruments available on board the spacecraft, the lidar (laser radar) and the UV/Visible camera is used in the covariance analysis to obtain the spacecraft delivery uncertainties at the asteroid. These uncertainties are due primarily to asteroid ephemeris uncertainties. On board optical navigation reduces the uncertainty in the knowledge of the spacecraft position in the direction perpendicular to the incoming asymptote to a one-sigma value of under 1 km, at the closest approach distance of 100 km. The uncertainty in the knowledge of the encounter time is about 0.1 seconds for a flyby velocity of 10.85 km/s. The magnitude of these uncertainties is due largely to Center Finding Errors (CFE). These systematic errors represent the accuracy expected in locating the center of the asteroid in the optical navigation images, in the absence of a topographic model for the asteroid. The direction of the incoming asymptote cannot be estimated accurately until minutes before the asteroid flyby, and correcting for it would require autonomous navigation. Orbit determination errors dominate over maneuver execution errors, and the final delivery accuracy attained is basically the orbit determination uncertainty before the final maneuver.

  16. The Astrometric Recognition of the Solar Clementine Gnomon (1702)

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    The Clementine gnomon has been built in 1702 to measure the Earth's obliquity variation. For this reason the pinhole was located in the walls of Diocletian's times (305 a. D.) in order to remain stable along the centuries, but its original form and position have been modified. We used an astrometric method to recover the original position of the pinhole: reshaping the pinhole to a circle of 1.5 cm of diameter, the positions of the Northern and Southern limbs have been compared with the ephemerides. A sistematic shift of 4.5 mm Southward of the whole solar image shows that the original pinhole was 4.5 mm North of the actual position, as the images in the Bianchini's book (1703) suggest. The oval shape of the actual pinhole is also wrong. Using a circle the larger solar spots are clearly visible. Some reference stars of the catalogue of Philippe de la Hire (1702), used originally for measuring the ecliptic latitude of the Sun, are written next to the meridian line, but after the last restauration (2000), four of them are wrongly located. Finally the deviation from the true North, of the meridian line's azimuth confirms the value recovered in 1750. This, with the local deviations of a true line, will remain as systematic error, like for all these historical instruments.

  17. Citrus juice extraction systems: effect on chemical composition and antioxidant activity of clementine juice.

    PubMed

    Álvarez, Rafael; Carvalho, Catarina P; Sierra, Jelver; Lara, Oscar; Cardona, David; Londoño-Londoño, Julian

    2012-01-25

    Clementines are especially appreciated for their delicious flavor, and recent years have seen a great increase in the consumption of clementine juice. In previous decades, antioxidant compounds have received particular attention because of widely demonstrated beneficial health effects. In this work, the organoleptic, volatile flavor, and antioxidant quality of clementine juice were studied with regard to the influence on them by different juice extraction systems: plug inside fruit and rotating cylinders. The results showed that juice extracted by the former method presented higher yields and hesperidin content, which was related to higher antioxidant activity, demonstrated by ORAC and LDL assays. The organoleptic quality was not affected by the processing technique, whereas there were significant differences in the chemical flavor profile. There are important differences in chemical and functional quality between juice extraction techniques, which must be taken into account when employing processing systems to produce high-quality products.

  18. Characterization and comparison of volatile constituents of juice and peel from clementine, mandarin and their hybrids.

    PubMed

    Barboni, Toussaint; Paolini, Julien; Tomi, Pierre; Luro, Fançois; Muselli, Alain; Costa, Jean

    2011-10-01

    The volatile compositions of juice and peel of clementine (Citrus reticulata x Citrus sinensis var. Commune), mandarin (Citrus reticulata Blanco var. Willow Leaf) and their hybrids were analyzed by headspace solid-phase extraction (HS-SPME) coupled with gas chromatography and either a flame ionization detector (FID) or a mass spectrometer (MS). The major compounds of the volatile fractions of clementine and mandarin were limonene and limonene/gamma-terpinene, respectively. The volatile compositions of juice and peel of the same fruit showed qualitative and quantitative differences. The data analysis established the existence of three main groups based on volatile compounds that correlated with sample genotypes (clementine and mandarin) and fruit samples (peel and juice).

  19. Characterization and comparison of volatile constituents of juice and peel from clementine, mandarin and their hybrids.

    PubMed

    Barboni, Toussaint; Paolini, Julien; Tomi, Pierre; Luro, Fançois; Muselli, Alain; Costa, Jean

    2011-10-01

    The volatile compositions of juice and peel of clementine (Citrus reticulata x Citrus sinensis var. Commune), mandarin (Citrus reticulata Blanco var. Willow Leaf) and their hybrids were analyzed by headspace solid-phase extraction (HS-SPME) coupled with gas chromatography and either a flame ionization detector (FID) or a mass spectrometer (MS). The major compounds of the volatile fractions of clementine and mandarin were limonene and limonene/gamma-terpinene, respectively. The volatile compositions of juice and peel of the same fruit showed qualitative and quantitative differences. The data analysis established the existence of three main groups based on volatile compounds that correlated with sample genotypes (clementine and mandarin) and fruit samples (peel and juice). PMID:22164792

  20. Clementine Star Tracker Stellar Compass: Final report part 1

    SciTech Connect

    Priest, R.E.; Kordas, J.F.; Lewis, I.T.

    1995-07-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star stracker stellar compasses (star tracker camera + stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 x 384 focal plane array and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 m{sub v}, providing rms pointing accuracy of better than 100 {mu}rad pitch and yaw and 450 {mu}rad roll. A description of this light-weight, low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights. Documentation generated during the design, analysis, build, test and characterization of the star tracker cameras are presented. Collectively, this documentation represents a small library of information for this camera, and may be used as a framework for producing copy units by commercial enterprises, and therefore satisfies a Department of Defense and Department of Energy goal to transfer technology to industry. However, the considerable knowledge gained from the experience of the individuals involved in the system trades, design, analysis, production, testing and characterization of the star tracker stellar compass is not contained in this documentation.

  1. REACTOR

    DOEpatents

    Christy, R.F.

    1961-07-25

    A means is described for co-relating the essential physical requirements of a fission chain reaction in order that practical, compact, and easily controllable reactors can be built. These objects are obtained by employing a composition of fissionsble isotope and moderator in fluid form in which the amount of fissionsble isotcpe present governs the reaction. The size of the reactor is no longer a critical factor, the new criterion being the concentration of the fissionable isotope.

  2. REACTOR

    DOEpatents

    Szilard, L.

    1963-09-10

    A breeder reactor is described, including a mass of fissionable material that is less than critical with respect to unmoderated neutrons and greater than critical with respect to neutrons of average energies substantially greater than thermal, a coolant selected from sodium or sodium--potassium alloys, a control liquid selected from lead or lead--bismuth alloys, and means for varying the quantity of control liquid in the reactor. (AEC)

  3. Geometric Calibration of the Clementine UVVIS Camera Using Images Acquired by the Lunar Reconnaissance Orbiter

    NASA Astrophysics Data System (ADS)

    Speyerer, E. J.; Wagner, R. V.; Robinson, M. S.

    2016-06-01

    The Clementine UVVIS camera returned over half a million images while in orbit around the Moon in 1994. Since the Clementine mission, our knowledge of lunar topography, gravity, and the location of features on the surface has vastly improved with the success of the Gravity Recovery and Interior Laboratory (GRAIL) mission and ongoing Lunar Reconnaissance Orbiter (LRO) mission. In particular, the Lunar Reconnaissance Orbiter Camera (LROC) has returned over a million images of the Moon since entering orbit in 2009. With the aid of improved ephemeris and on-orbit calibration, the LROC team created a series of precise and accurate global maps. With the updated reference frame, older lunar maps, such as those generated from Clementine UVVIS images, are misaligned making cross-mission analysis difficult. In this study, we use feature-based matching routines to refine and recalibrate the interior and exterior orientation parameters of the Clementine UVVIS camera. After applying these updates and rigorous orthorectification, we are able generate precise and accurate maps from UVVIS images to help support lunar science and future cross-mission investigations.

  4. Apollo 14 Impact Glasses and Clementine Data: Implications for Regional Geology

    NASA Technical Reports Server (NTRS)

    Zellner, N. E. B.; Spudis, P. D.; Delano, J. W.; Whittet, D. C. B.

    2002-01-01

    Clementine color image data and analyses of 778 lunar impact glasses have been used together to suggest that the highlands of the Fra Mauro region consist of a KREEP-rich regolith overlying a feldspathic terrain. Low-KREEP impact glasses may possess a memory of impacts prior to 3.9 Ga ago. Additional information is contained in the original extended abstract.

  5. REACTOR

    DOEpatents

    Roman, W.G.

    1961-06-27

    A pressurized water reactor in which automatic control is achieved by varying the average density of the liquid moderator-cooiant is patented. Density is controlled by the temperature and power level of the reactor ftself. This control can be effected by the use of either plate, pellet, or tubular fuel elements. The fuel elements are disposed between upper and lower coolant plenum chambers and are designed to permit unrestricted coolant flow. The control chamber has an inlet opening communicating with the lower coolant plenum chamber and a restricted vapor vent communicating with the upper coolant plenum chamber. Thus, a variation in temperature of the fuel elements will cause a variation in the average moderator density in the chamber which directly affects the power level of the reactor.

  6. Global Mapping of Mg-Number Derived from Clementine Data.

    NASA Astrophysics Data System (ADS)

    Cahill, J. T.; Lucey, P. G.; Gillis, J. J.; Steutel, D.

    2004-12-01

    environmental space exposure on the optical properties of these minerals. This was accomplished using Clementine ultraviolet and visible (UVVIS) data and a Hapke radiative transfer mixing model. The major features evident in these maps are the strong distinction between mare and highland regions, the former showing low Mg* and the latter generally higher; a large northern highlands unit with low Mg*, and an Mg* high north of South Pole-Aitken basin. Mare units are not universally low, mare Frigoris in particular has elevated Mg* relative to other mare. The strongest variations in the highlands occur in plagioclase rich, low FeO units, that exhibit values ranging near 50 to near 100 in coherent units. The craters Tycho and Aristarchus also exhibit high Mg*; these gabbroic anomalies may indicate more extensive Mg-rich material at depth. Deposits within SPA are unremarkable relative to surroundings, and share the intermediate Mg* of most of the highlands. 1. James, O.B. et al. PLPSC. 1989.; 2.Bersch, M.G., et al., GRL, 1991.; 3. Floss, C., et al., GCA, 1998.; 4. Korotev, R.L., et al., GCA, 2003.

  7. Multispectral Photometry of the Moon and Absolute Calibration of the Clementine UV/Vis Camera

    NASA Astrophysics Data System (ADS)

    Hillier, John K.; Buratti, Bonnie J.; Hill, Kathryn

    1999-10-01

    We present a multispectral photometric study of the Moon between solar phase angles of 0 and 85°. Using Clementine images obtained between 0.4 and 1.0 μm, we produce a comprehensive study of the lunar surface containing the following results: (1) empirical photometric functions for the spectral range and viewing and illumination geometries mentioned, (2) photometric modeling that derives the physical properties of the upper regolith and includes a detailed study of the causes for the lunar opposition surge, (3) an absolute calibration of the Clementine UV/Vis camera. The calibration procedure given on the Clementine calibration web site produces reflectances relative to a halon standard and further appear significantly higher than those seen in groundbased observations. By comparing Clementine observations with prior groundbased observations of 15 sites on the Moon we have determined a good absolute calibration of the Clementine UV/Vis camera. A correction factor of 0.532 has been determined to convert the web site (www.planetary.brown.edu/clementine/calibration.html) reflectances to absolute values. From the calibrated data, we calculate empirical phase functions useful for performing photometric corrections to observations of the Moon between solar phase angles of 0 and 85° and in the spectral range 0.4 to 1.0μm. Finally, the calibrated data is used to fit a version of Hapke's photometric model modified to incorporate a new formulation, developed in this paper, of the lunar opposition surge which includes coherent backscatter. Recent studies of the lunar opposition effect have yielded contradictory results as to the mechanism responsible: shadow hiding, coherent backscatter, or both. We find that most of the surge can be explained by shadow hiding with a halfwidth of ˜8°. However, for the brightest regions (the highlands at 0.75-1.0μm) a small additional narrow component (halfwidth of <2°) of total amplitude ˜1/6 to 1/4 that of the shadow hiding surge is

  8. The Lunar Crustal Thickness from Analysis of the Lunar Prospector Gravity and Clementine Topography Datasets

    NASA Technical Reports Server (NTRS)

    Asmar, S.; Schubert, G.; Konopliv, A.; Moore, W.

    1999-01-01

    The Lunar Prospector spacecraft has mapped the gravity field of the Moon to a level of resolution never achieved before, and a spherical harmonic representation to degree and order 100 is available. When combined with the topography dataset produced by the Clementine mission, the resulting Bouguer anomaly map is interpreted to model the thickness of the lunar crust. Such models are crucial to understanding the lunar thermal history and the formation of geological features such as mascon basins, several more of which have been newly discovered from this dataset. A two-layer planetary model was used to compute the variations of the depth to the lunar Moho. The thickness values ranged from near 0 to 120 km. There is significant agreement with previous work using the Clementine gravitational field data with differences in specific locations such as South Pole-Aitken Basin, for example.

  9. New Data on Lunar Topography Derived from Galileo and Clementine Stereo Images

    NASA Astrophysics Data System (ADS)

    Oberst, J.; Wahlisch, M.; Zhang, W.; Roatsch, T.; Cook, A. C.; Jaumann, R.

    1996-03-01

    We analyzed images, obtained by the Galileo and Clementine spacecraft in 1992 and 1994 using state-of-the-art photogrammetric techniques to derive Digital Terrain Models (DTMs) for selected lunar regions. These regions include: the near-side northern hemisphere, parts of Mare Orientale, and the Alpine Valley. The new topographic data allow us to study the morphology of the Moon, in particular large craters and the multi-ring impact basins in unprecedented detail.

  10. Reactor

    DOEpatents

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  11. Approaches for sampling the twospotted spider mite (Acari: Tetranychidae) on clementines in Spain.

    PubMed

    Martínez-Ferrer, M T; Jacas, J A; Ripollés-Moles, J L; Aucejo-Romero, S

    2006-08-01

    Tetranychus urticae Koch (Acari: Tetranychidae) is an important pest of clementine mandarins, Citrus reticulata Blanco, in Spain. As a first step toward the development of an integrated crop management program for clementines, dispersion patterns of T. urticae females were determined for different types of leaves and fruit. The study was carried out between 2001 and 2003 in different commercial clementine orchards in the provinces of Castelló and Tarragona (northeastern Spain). We found that symptomatic leaves (those exhibiting typical chlorotic spots) harbored 57.1% of the total mite counts. Furthermore, these leaves were representative of mite dynamics on other leaf types. Therefore, symptomatic leaves were selected as a sampling unit. Dispersion patterns generated by Taylor's power law demonstrated the occurrence of aggregated patterns of spatial distribution (b > 1.21) on both leaves and fruit. Based on these results, the incidence (proportion of infested samples) and mean density relationship were developed. We found that optimal binomial sample sizes for estimating low populations of T. urticae on leaves (up to 0.2 female per leaf) were very large. Therefore, enumerative sampling would be more reliable within this range of T. urticae densities. However, binomial sampling was the only valid method for estimating mite density on fruit.

  12. Geology of Lunar Landing Sites and Origin of Basin Ejecta from a Clementine Perspective

    NASA Technical Reports Server (NTRS)

    Jolliff, Bradley L.; Haskin, Larry A.

    1998-01-01

    The goals of this research were to examine Clementine multispectral data covering the Apollo landing sites in order to: (1) provide ground truth for the remotely sensed observations, (2) extend our understanding of the Apollo landing sites to the surrounding regions using the empirically calibrated Clementine data, and (3) investigate the composition and distribution of impact-basin ejecta using constraints based upon the remotely sensed data and the Apollo samples. Our initial efforts (in collaboration with P. Lucey and coworkers) to use the Apollo soil compositions to "calibrate" information derived from the remotely sensed data resulted in two extremely useful algorithms for computing estimates of the concentrations of FeO and TiO2 from the UV-VIS 5-band data. In this effort, we used the average surface soil compositions from 37 individual Apollo and 3 Luna sample stations that could be resolved using the Clementine data. We followed this work with a detailed investigation of the Apollo 17 landing site, where the sampling traverses were extensive and the spectral and compositional contrast between different soils covers a wide range. We have begun to investigate the nature and composition of basin ejecta by comparing the thick deposits on the rim of Imbrium in the vicinity of the Apollo 15 site and those occurring southeast of the Serenitatis basin, in the Apollo 17 region. We continue this work under NAG5-6784, "Composition, Lithology, and Heterogeneity of the lunar crust using remote sensing of impact-basin uplift structures and ejecta as probes. The main results of our work are given in the following brief summaries of major tasks. Detailed accounts of these results are given in the attached papers, manuscripts, and extended abstracts.

  13. The south pole region of the moon as seen by Clementine

    USGS Publications Warehouse

    Shoemaker, E.M.; Robinson, M.S.; Eliason, E.M.

    1994-01-01

    The Clementine mission has provided the first comprehensive set of high-resolution images of the south pole region of the moon. Within 5?? of latitude of the pole, an area of an estimated 30,000 square kilometers remained in shadow during a full lunar rotation and is a promising target for future exploration for ice deposits. The Schrodinger Basin (320 kilometers in diameter), centered at 75??S, is one of the two youngest, least modified, great multiring impact basins on the moon. A large maar-type volcano localized along a graben within the Schrodinger Basin probably erupted between 1 and 2 billion years ago.

  14. Lunar Fe and Ti abundances: comparison of lunar prospector and clementine data

    PubMed

    Elphic; Lawrence; Feldman; Barraclough; Maurice; Binder; Lucey

    1998-09-01

    The Lunar Prospector neutron spectrometer data correlate well with iron and titanium abundances obtained through analysis of Clementine spectral reflectance data. With the iron and titanium dependence removed, the neutron spectrometer data also reveal regions with enhanced amounts of gadolinium and samarium, incompatible rare earth elements that are enriched in the final phases of magma crystallization. These regions are found mainly around the ramparts of the Imbrium impact basin but not around the other basins, including the much larger and deeper South Pole-Aitken basin. This result confirms the compositional uniqueness of the surface and interior of the Imbrium region.

  15. The shape and internal structure of the moon from the clementine mission.

    PubMed

    Zuber, M T; Smith, D E; Lemoine, F G; Neumann, G A

    1994-12-16

    Global topographic and gravitational field models derived from data collected by the Clementine spacecraft reveal a new picture of the shape and internal structure of the moon. The moon exhibits a 16-kilometer range of elevation, with the greatest topographic excursions occurring on the far side. Lunar highlands are in a state of near-isostatic compensation, whereas impact basins display a wide range of compensation states that do not correlate simply with basin size or age. A global crustal thickness map reveals crustal thinning under all resolvable lunar basins. The results indicate that the structure and thermal history of the moon are more complex than was previously believed.

  16. A 70th Degree Lunar Gravity Model (GLGM-2) from Clementine and other tracking data

    NASA Technical Reports Server (NTRS)

    Lemonie, Frank G. R.; Smith, David E.; Zuber, Maria T.; Neumann, Gregory A.

    1997-01-01

    A spherical harmonic model of the lunar gravity field complete to degree and order 70 has been developed from S band Doppler tracking data from the Clementine mission, as well as historical tracking data from Lunar Orbiters 1-5 and the Apollo 15 and 16 subsatellites. The model combines 361,000 Doppler observations from Clementine with 347,000 historical observations. The historical data consist of mostly 60-s Doppler with a noise of 0.25 to several mm/s. The Clementine data consist of mostly 10-s Doppler data, with a data noise of 0.25 mm/s for the observations from the Deep Space Network, and 2.5 mm/s for the data from a naval tracking station at Pomonkey, Maryland. Observations provided Clementine, provide the strongest satellite constraint on the Moon's low-degree field. In contrast the historical data, collected by spacecraft that had lower periapsis altitudes, provide distributed regions of high-resolution coverage within +/- 29 deg of the nearside lunar equator. To obtain the solution for a high-degree field in the absence of a uniform distribution of observations, we applied an a priori power law constraint of the form 15 x 10(exp -5)/sq l which had the effect of limiting the gravitational power and noise at short wavelengths. Coefficients through degree and order 18 are not significantly affected by the constraint, and so the model permits geophysical analysis of effects of the major basins at degrees 10-12. The GLGM-2 model confirms major features of the lunar gravity field shown in previous gravitational field models but also reveals significantly more detail, particularly at intermediate wavelengths (10(exp 3) km). Free-air gravity anomaly maps derived from the new model show the nearside and farside highlands to be gravitationally smooth, reflecting a state of isostatic compensation. Mascon basins (including Imbrium, Serenitatis, Crisium, Smythii, and Humorum) are denoted by gravity highs first recognized from Lunar Orbiter tracking. All of the major

  17. Production of transgenic adult plants from clementine mandarin by enhancing cell competence for transformation and regeneration.

    PubMed

    Cervera, Magdalena; Navarro, Antonio; Navarro, Luis; Peña, Leandro

    2008-01-01

    Genetic transformation of mature trees is difficult because adult tissues are recalcitrant to Agrobacterium tumefaciens infection and transformation and because transgenic mature events are less competent for regeneration. We have shown that reinvigoration allows manipulation of the vegetative phase to increase the potential for transformation and regeneration without loss of competence for flowering and fruiting. To produce transgenic plants from clementine mandarin (Citrus clementina hort. ex Tanaka), we optimized the conditions of the source material both ex vitro and in vitro. Grafting of mature buds on juvenile rootstocks in the spring and preventing multiple bud sprouting by removing all but one bud permitted selection of vigorous first flushes for in vitro culture. Use of additional virulence genes from A. tumefaciens to increase transformation frequency and optimization of culture media and conditions to enhance explant cell competence for T-DNA integration and organogenesis resulted in efficient and reliable transgenic plant production. Transformed regenerants from explants, cultured in media without antibiotics, were identified by a screenable marker (either beta-glucuronidase or green fluorescent protein (GFP)), creating the possibility of generating transgenic clementine plants without antibiotic resistance marker genes. Stable integration of foreign genes was demonstrated by Southern blot analysis, and expression of these foreign genes was confirmed by detection of GFP fluorescence in leaves, floral organs and fruits of the transgenic plants.

  18. Economic threshold for Tetranychus urticae (Acari: Tetranychidae) in clementine mandarins Citrus clementina.

    PubMed

    Pascual-Ruiz, Sara; Aguilar-Fenollosa, Ernestina; Ibáñez-Gual, Victoria; Hurtado-Ruiz, Mónica A; Martínez-Ferrer, M Teresa; Jacas, Josep A

    2014-03-01

    Tetranychus urticae is a key pest of citrus in Spain, especially of clementine mandarin trees. The effects of this mite on fruit production were assessed in 24 clementine trees for three consecutive years. Trees were visited weekly and spider mite and phytoseiid mite populations and leaf flush patterns were estimated. At the end of the season, mandarins were harvested, weighed, and mite damage (scarring on the fruit) characterized. Negative relationships between spider mite density and yield (kg/tree) and fruit damage (% scarred fruit rind) were found. The multivariate regressions highlighted the key role of phytoseiid mites and leaf flush patterns, which were negatively related to fruit damage. The shortest sampling period that satisfactorily predicted fruit damage at harvest, extended from August to mid-October. For IPM purposes, an action threshold of 31.1 mites m⁻² of symptomatic leaf was estimated. Taking into account spider mite dynamics, the economic threshold ranged from 10 to 15 mites m⁻² of symptomatic leaf. When this threshold is exceeded growers would have a 1-week window to apply the control technologies against T. urticae of their choice.

  19. A New Global Digital Map of the Moon from Clementine Image Data

    NASA Astrophysics Data System (ADS)

    Becker, T. L.; Edwards, K. E.; Cook, D.; Eliason, E.; Lee, E. M.; McEwen, A. S.; Morgan, H.; Robinson, M. S.; Colvin, T.; Davies, M.; Duxbury, T.; Sorensen, T.

    1996-09-01

    A new cartographic control net for the Moon has been completed utilizing Clementine image data. Previous geometric control for the Moon contained errors of _˜1-2 km on the near side and up to _˜10 km for the far side. Selection of over 265,000 match points from _˜43,000 images has improved the global accuracy to _˜250 m/pixel. Several automated procedures were developed to aid in finding matchpoints, with a success rate exceeding 90%. These new mosaicking techniques will be applicable to future planetary datasets and are included in the ISIS software package available at no cost through the Internet (http://wwwflag.wr.usgs.gov/USGSFlag/Data/software/isis.html). Matchpoints were processed at RAND for analytic triangulation. Absolute control was obtained by holding known locations (such as Apollo landing sites) as truth. Camera angles for each image were updated using a least squares fit to minimize offsets between matchpoints. The mean error for the entire Moon is less than 1 pixel. The final 1 km monochromatic basemap was constructed using 750 nm images except where gaps existed in the coverage; these gaps were filled using 900 nm images, empirically fit to match the brightness of the adjacent 750 nm data. The data have been normalized to a phase angle of 30deg using an improved photometric function derived from Clementine and Galileo image data. Work is currently underway processing the remaining bands covering the wavelength range of 415-2780 nm.

  20. Carbohydrate control over carotenoid build-up is conditional on fruit ontogeny in clementine fruits.

    PubMed

    Poiroux-Gonord, Florine; Fanciullino, Anne-Laure; Poggi, Isabelle; Urban, Laurent

    2013-04-01

    The final contents of primary and secondary metabolites of the ripe fruit depend on metabolic processes that are tightly regulated during fruit ontogeny. Carbohydrate supply during fruit development is known to influence these processes but, with respect to secondary metabolites, we do not really know whether this influence is direct or indirect. Here, we hypothesized that the sensitivity of clementine fruit metabolism to carbohydrate supply was conditional on fruit developmental stage. We applied treatments increasing fruit load reversibly or irreversibly at three key stages of clementine (Citrus clementina Hort. ex Tan.) fruit development: early after cell division, at the onset of fruit coloration (color break) and near maturity. The highest fruit load obtained by early defoliation (irreversible) had the highest impact on fruit growth, maturity and metabolism, followed by the highest fruit load obtained by early shading (reversible). Final fruit size decreased by 21 and 18% in these early irreversible and reversible treatments, respectively. Soluble sugars decreased by 18% in the early irreversible treatment, whereas organic acids increased by 46 and 29% in these early irreversible and reversible treatments, respectively. Interestingly, total carotenoids increased by 50 and 18%, respectively. Changes in leaf starch content and photosynthesis supported that these early treatments triggered a carbon starvation in the young fruits, with irreversible effects. Furthermore, our observations on the early treatments challenge the common view that carbohydrate supply influences positively carotenoid accumulation in fruits. We propose that early carbon starvation irreversibly promotes carotenoid accumulation.

  1. The Clementine Hunter Black History Month Exhibit: Successful Demonstration and Results of the Display Process. Working Paper #1.

    ERIC Educational Resources Information Center

    Demery, Marie

    The Clementine Hunter Black History Month Exhibition (Natchitoches, Louisiana) was a successful demonstration that five objectives can be achieved with a zero budget and teamwork. Objective 1 demonstrated that specially designed cultural and extracurricular events can be used as tools for retaining black students on a predominantly white college…

  2. Mineralogy of the Moon by multiple endmember spectral unmixing of Clementine UVVIS and NIR data

    NASA Astrophysics Data System (ADS)

    Combe, J.; Kramer, G.; Thomas, M. B.

    2007-12-01

    Global observations of the Moon have been made by the imaging spectrometers onboard the Clementine spacecraft in 1994 [1]. These data have 5 channels in the Ultra-Violet Visible (UVVIS) in the range 450-1000 nm and 6 in the Near Infra-Red (NIR) in the range 1100-2780 nm. UVVIS global mosaic has been widely used in spectral analysis (e.g. [2, 3]). Calibration issues in the NIR data did not favor spectral studies using the full wavelength range [4]. Only a few analyses have been made in the NIR using different calibration approaches (e.g. [5]), despite potential valuable information to discriminate more minerals. A new calibration has finally been applied on the NIR [6, 7] and a mosaic calibrated in Bidirectional Reflectance (BRDF) has been released [8]. Quantitative mapping of minerals is possible using Clementine data 1) by converting BRDF into single scattering albedo [9, 10] and 2) by performing spectral linear unmixing [11]. Multiple-Endmember Spectral Mixture Analysis (MESMA, [12]) has been successfully applied with UVVIS data [11]. This method allows spectral unmixing to be calculated using a limited number of components, even if a lot more spectral endmembers are available in the reference spectral library. We have analyzed newly calibrated Clementine UVVIS and NIR data using a multiple-endmember linear spectral linear unmixing algorithm [13]. The model works either with spectra collected from the image or from laboratory measurements of pure minerals. Components are selected on spectral interpretation and knowledge of lunar soils and surface processes. Variation in the spectral slope varies with surface maturity and TiO2 content [14]. Including a slope endmember in the reference spectral library allows the mineralogy to be mapped independently of maturity effects. [1] Nozette S., et. al., 1994, Science, 266 [2] Lucey P. G., 2004, GRL 31. [3] Pieters C. M. et al., 2006, Icarus, 184. [4] Lucey P. G. et al., 1998, LPSC abstract 1576. [5] Le Mouelic et al., 1999

  3. HiRes camera and LIDAR ranging system for the Clementine mission

    SciTech Connect

    Ledebuhr, A.G.; Kordas, J.F.; Lewis, I.T.

    1995-04-01

    Lawrence Livermore National Laboratory developed a space-qualified High Resolution (HiRes) imaging LIDAR (Light Detection And Ranging) system for use on the DoD Clementine mission. The Clementine mission provided more than 1.7 million images of the moon, earth, and stars, including the first ever complete systematic surface mapping of the moon from the ultra-violet to near-infrared spectral regions. This article describes the Clementine HiRes/LIDAR system, discusses design goals and preliminary estimates of on-orbit performance, and summarizes lessons learned in building and using the sensor. The LIDAR receiver system consists of a High Resolution (HiRes) imaging channel which incorporates an intensified multi-spectral visible camera combined with a Laser ranging channel which uses an avalanche photo-diode for laser pulse detection and timing. The receiver was bore sighted to a light-weight McDonnell-Douglas diode-pumped ND:YAG laser transmitter that emmitted 1.06 {micro}m wavelength pulses of 200 mJ/pulse and 10 ns pulse-width, The LIDAR receiver uses a common F/9.5 Cassegrain telescope assembly. The optical path of the telescope is split using a color-separating beamsplitter. The imaging channel incorporates a filter wheel assembly which spectrally selects the light which is imaged onto a custom 12 mm gated image intensifier fiber-optically-coupled into a 384 x 276 pixel frame transfer CCD FPA. The image intensifier was spectrally sensitive over the 0.4 to 0.8 {micro}m wavelength region. The six-position filter wheel contained 4 narrow spectral filters, one broadband and one blocking filter. At periselene (400 km) the HiRes/LIDAR imaged a 2.8 km swath width at 20-meter resolution. The LIDAR function detected differential signal return with a 40-meter range accuracy, with a maximum range capability of 640 km, limited by the bit counter in the range return counting clock.

  4. The South pole region of the moon as seen by clementine.

    PubMed

    Shoemaker, E M; Robinson, M S; Eliason, E M

    1994-12-16

    The Clementine mission has provided the first comprehensive set of high-resolution images of the south pole region of the moon. Within 5 degrees of latitude of the pole, an area of an estimated 30,000 square kilometers remained in shadow during a full lunar rotation and is a promising target for future exploration for ice deposits. The Schrödinger Basin (320 kilometers in diameter), centered at 75 degrees S, is one of the two youngest, least modified, great multiring impact basins on the moon. A large maar-type volcano localized along a graben within the Schrödinger Basin probably erupted between 1 and 2 billion years ago.

  5. The clementine bistatic radar experiment: Evidence for ice on the moon

    USGS Publications Warehouse

    Spudis, P.D.; Nozette, S.; Lichtenberg, C.; Bonner, R.; Ort, W.; Malaret, E.; Robinson, M.; Shoemaker, E.

    1998-01-01

    Ice deposits, derived from comets and water-bearing meteorites hitting the Moon over geological times, have long been postulated to exist in dark areas near the poles of the Moon. The characteristics of radio waves beamed from the Clementine spacecraft into the polar areas, reflected from the Moon's surface, and received on the large dish antennas of the Deep Space Network here on Earth show that roughly the volume of a small lake (???0.9-1.8 km3) of water ice makes up part of the Moon's surface layer near the south pole. The discovery of ice near the lunar south pole has important ramifications for a permanent return to the Moon. These deposits could be used to manufacture rocket propellant and to support human life on the Moon. ?? 1998 MAHK Hayka/Interperiodica Publishing.

  6. A Near-Infrared (NIR) Global Multispectral Map of the Moon from Clementine

    NASA Technical Reports Server (NTRS)

    Eliason, E. M.; Lee, E. M.; Becker, T. L.; Weller, L. A.; Isbell, C. E.; Staid, M. I.; Gaddis, L. R.; McEwen, A. S.; Robinson, M. S.; Duxbury, T.

    2003-01-01

    In May and June of 1994, the NASA/DoD Clementine Mission acquired global, 11- band, multispectral observations of the lunar surface using the ultraviolet-visible (UVVIS) and near-infrared (NIR) camera systems. The global 5-band UVVIS Digital Image Model (DIM) of the Moon at 100 m/pixel was released to the Planetary Data System (PDS) in 2000. The corresponding NIR DIM has been compiled by the U.S. Geological Survey for distribution to the lunar science community. The recently released NIR DIM has six spectral bands (1100, 1250, 1500, 2000, 2600, and 2780 nm) and is delivered in 996 quads at 100 m/pixel (303 pixels/degree). The NIR data were radiometrically corrected, geometrically controlled, and photometrically normalized to form seamless, uniformly illuminated mosaics of the lunar surface.

  7. [Use of morphological and physiological characters, and molecular markers to evaluate the genetic diversity of three clementine cultivars].

    PubMed

    Chahidi, Bouchra; El-Otmani, Mohamed; Jacquemond, Camille; Tijane, M'hamed; El-Mousadik, Abdelhamid; Srairi, Ikbal; Luro, François

    2008-01-01

    Originating from a natural crossing between mandarin and sweet orange at the end of the 19(th) century, clementine diversified through the selection of spontaneous mutations. Today, it seems almost impossible to distinguish one variety from another. The development of molecular tools for variety identification is thus necessary. Three clementine cultivars, representing distinct groups of fruit maturity, were evaluated. Identification criteria were searched at the phenotypical level (organoleptic characteristics, leaves morphology) as well as the DNA level (isozymes, RAPD, and ISSR). The phenotypical diversity observed is relatively high and contrasted with the low molecular polymorphism. In fact, only the cultivar 'Guerdane' presents profiles of genetic fingerprints different from those of the two other cultivars. The frequency of the genetic modifications would thus be variable from a cultivar to another. Moreover, the specific molecular markers of the cultivar 'Guerdane', added to the phenotypic markers, extend the possibilities of identification to the young nursery plants.

  8. Assessment of Navel Oranges, Clementine Tangerines, and Rutaceous Fruits as Hosts of Bactrocera cucurbitae and Bactrocera latifrons (Diptera: Tephritidae).

    PubMed

    McQuate, Grant T; Follett, Peter A; Liquido, Nicanor J; Sylva, Charmaine D

    2015-01-01

    Export of Citrus spp. fruits may require risk mitigation measures if grown in areas with established tephritid fruit fly (Diptera: Tephritidae) populations capable of infesting the fruits. The host status of Citrus spp. fruits is unclear for two tephritid fruit fly species whose geographic ranges have expanded in recent years: melon fly, Bactrocera cucurbitae (Cocquillett), and Bactrocera latifrons (Hendel). In no choice cage infestation studies, B. latifrons oviposited into intact and punctured Washington navel oranges (Citrus sinensis [L.] Osbeck) and Clementine tangerines (C. reticulata L. var. Clementine), but eggs rarely developed to the adult stage. B. cucurbitae readily infested intact and punctured tangerines, and to a lesser extent punctured oranges, but did not infest intact oranges. Limited cage infestation and only a single literature report of field Citrus spp. infestation suggest that risk mitigation of Citrus spp. for B. latifrons is not needed. Risk mitigation options of Citrus spp. for B. cucurbitae, including heat and cold treatments and systems approaches, are discussed.

  9. Genetic structure of a phytophagous mite species affected by crop practices: the case of Tetranychus urticae in clementine mandarins.

    PubMed

    Pascual-Ruiz, S; Gómez-Martinez, M A; Ansaloni, T; Segarra-Moragues, J G; Sabater-Muñoz, B; Jacas, J A; Hurtado-Ruiz, M A

    2014-04-01

    Tetranychus urticae Koch is a cosmopolitan mite considered as the most polyphagous species among spider mites. This mite is a key pest of clementine mandarins in Eastern Spain, where Spanish clementine production concentrates. Crop management practices can affect the population dynamics of this mite and, consequently, its impact on the orchard. Microsatellite markers were used to study mite population genetics from two commercial orchards which had been managed differently following Integrated Pest Management (IPM) or Organic Pest Management (OPM) schemes during four consecutive years. A multiplex system including 20 microsatellite loci was designed specifically and allowed an efficient and inexpensive genotyping of individual mites. We found that the IPM population had a stronger fluctuation of population structure and higher genetic diversity compared to OPM population. Thus, our study concludes that crop management has an impact on the population genetics of T. urticae which may be related to the alternation of some acaricides under IPM.

  10. Effects of rootstock and flushing on the incidence of three insects on 'Clementine de Nules' citrus trees.

    PubMed

    Muñoz, S Trapero; García, A Hervalejo; Pérez, M Jiménez; Boyero, J R; Vela, J M; Martínez-Ferri, E

    2008-12-01

    We evaluated the influence of six different citrus rootstocks on the incidence of the citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), and the aphid species, Aphis gossypii Glover and A. spiraecola Patch (Hemiptera: Aphididae), on 'Clementine de Nules' trees (Citrus clementina Hort. ex Tan.). Sampling was conducted during 2005 and 2006 in a grove of 3-yr-old trees in southern Spain with six rootstocks arranged in a completely randomized block design. Incidence (i.e., degree of infestation) and availability of resources for herbivores were assessed bi-weekly, and in addition, a "flushing index" was estimated as the number of young shoots (as a percentage of total shoots) susceptible to herbivore injury. Our results showed that contrasting factors affected the incidence of populations of P. citrella, A. gossypii, and A. spiraecola on 'Clementine de Nules'. Incidence of P. citrella was significantly dependent on the flushing pattern observed throughout the study, whereas the reverse was true for the aphid species. Among these, A. spiraecola had similar levels of incidence regardless of rootstock, whereas A. gossypii were found almost exclusively on leaves of 'Clementine de Nules' grafted on 'Cleopatra mandarin' (Citrus reshni Hort. ex Tan). Potential implications of these results on pest control are discussed.

  11. The Moon as a Spectral Calibration Standard Enabled by Lunar Samples: The Clementine Example

    NASA Astrophysics Data System (ADS)

    Pieters, C. M.

    1999-01-01

    Special calibration of Clementine data relies on the Apollo 16 site and laboratory measurements of mature soil 62231.The process produces calibrated spectra reflectance factors. What color is the Moon? A reflectance spectrum is essentially a measure of how much radiation incident on a surface (solar radiation) is reflected and how much is absorbed at each wavelength. To the eye the Moon is gray-white, but to photoelectric instruments it is various shades of red - that is, it exhibits an increase in brightness with wavelength. In the near-infrared there are absorptions diagnostic of minerals superimposed on the Moon's redness. For the Moon and other rocky bodies such as asteroids, most of the detectable absorptions arise from ferrous iron in various crystallographic sites. The wavelength, shape, and strength of these absorptions identify the minerals present, and allow their abundances to be estimated. Accurately measuring these diagnostic mineral absorptions with remote detectors requires not only a quality instrument, but also excellent electronic calibration and either direct measurement of the light source (the Sun) or a proxy, or a well-known reference standard illuminated by the same light source. In the laboratory a white reference such as halon (or commercial Spectralon), is used which in turn has been extensively calibrated relative to a known radiance. In space, or at the telescope, a separate reference must be found to mimic solar radiation and to eliminate instrumental and atmospheric effects. Radiation from stars to a first order follows a black body spectral curve with multiple emission and absorption lines superimposed. Because stellar lines vary with spectral type, and very few stars are really solar-like, it is actually quite difficult to use stars as spectral standards. The Moon is a nearby atmosphereless body that reflects solar radiation. Because the Moon's surface itself does not change with time (at least within our lifetimes), it provides an

  12. Microtextured metals for stray-light suppression in the Clementine startracker

    NASA Technical Reports Server (NTRS)

    Johnson, E. A.

    1993-01-01

    Anodized blacks for suppressing stray light in optical systems can now be replaced by microscopically textured metal surfaces. An application of these black surfaces to the Clementine star-tracker navigational system, which will be launched in early 1994 to examine the Moon, en route to intercept an asteroid, is detailed. Rugged black surfaces with Lambertian BRDF less than 10(exp -2) srad(sup -1) are critical for suppressing stray light in the star-tracker optical train. Previously available materials spall under launch vibrations to contaminate mirrors and lenses. Microtextured aluminum is nearly as dark, but much less fragile. It is made by differential ion beam sputtering, which generates light-trapping pores and cones slightly smaller than the wavelength to be absorbed. This leaves a sturdy but light-absorbing surface that can survive challenging conditions without generating debris or contaminants. Both seeded ion beams and plasma immersion (from ECR plasmas) extraction can produce these microscopic textures without fragile interfaces. Process parameters control feature size, spacing, and optical effects (THR, BRDF). Both broad and narrow absorption bands can be engineered with tuning for specific wavelengths and applications. Examples are presented characterized by FTIR in reflection librators (0.95 normal emissivity), heat rejection, and enhanced nucleate boiling.

  13. Analysis of three classes of small lunar pyroclastic deposits with Clementine data

    NASA Astrophysics Data System (ADS)

    Gaddis, Lisa; Robinson, Mark; Hawke, B. R.

    1997-03-01

    The U.S. Geological Survey's Integrated Software for Imaging Spectrometers (ISIS) software was used to create and examine Clementine UV-VIS multispectral mosaics (about 100 m/pixel) of areas representative of the three major compositional classes of small lunar pyroclastic deposits. Compositional analyses of these deposits may provide clues to the nature of deep-source late-stage volcanism and eruption mechanisms on the moon. Small deposits of the Atlas Crater, east of Aristoteles, and J. Herschel Crater regions are studied. The goals are (1) to understand the full extent of interdeposit compositional variations among small lunar pyroclastic deposits, (2) to evaluate the possible effects of soil maturation and lateral mixing on the 'true' compositions of these deposits, (3) to determine the prevalence and nature of intradeposit compositional variations previously observed in deposits of Alphonsus Crater, (4) to identify and characterize the juvenile components of these deposits, and (5) to understand the implications of these results for studying lunar eruption mechanisms.

  14. Why the aphid Aphis spiraecola is more abundant on clementine tree than Aphis gossypii?

    PubMed

    Mostefaoui, Houda; Allal-Benfekih, Leila; Djazouli, Zahr-Eddine; Petit, Daniel; Saladin, Gaëlle

    2014-02-01

    Aphis spiraecola and Aphis gossypii cause harmful damages on clementine tree orchards. Weekly surveys measured the abundance of aphids (larvae, winged and wingless adults) as well as of auxiliary insects and parameters of energy metabolism. Correlatively, soluble carbohydrates, total free amino acids, free proline and condensed tannins were quantified in control and infested leaves. Both aphid species showed parallel temporal variations, but A. spiraecola was consistently more abundant regardless of the stage. Amino acids had a positive effect on both aphid species abundance, but neither condensed tannins nor auxiliary insects seemed to modulate aphid populations. Interestingly, the leaf carbohydrate content was positively correlated with the abundance of A. spiraecola, but not with that of A. gossypii. Moreover, A. gossypii's abundance was significantly down-regulated by high proline concentrations. Thus, the higher abundance of A. spiraecola could be explained by a better tolerance to high proline contents and a better conversion of foliar energy metabolites.

  15. Reanalysis of Clementine Bistatic Radar Data from the Lunar South Pole

    NASA Technical Reports Server (NTRS)

    Simpson, Richard A.; Tyler, G. Leonard

    1998-01-01

    On 9 April 1994 the Clementine spacecraft high-gain antenna was aimed toward the Moon's surface and the resulting 13-cm wavelength radio echoes were received on Earth. Using these data, we have found that the lunar surface generally follows a Lambertian bistatic scattering function sigma(sub 0) = K(sub D)cos(theta(sub i) with K(sub D) approx. 0.003 for the opposite (expected) sense of circular polarization and K(sub D) approx. 0.001 for the same (unexpected) sense. But there are important deviations-of up to 50% in some parts of the echo spectrum-from this simple form. Based on an earlier analysis of these same data, Nozette et al. claimed detection of an enhancement in echoes with right circular polarization from regions near the South Pole in a near-backscatter geometry. Such behavior would be consistent with presence of perhaps large quantities of water ice near the Pole. We have been unable to reproduce that result. Although we find weak suggestions of enhanced echoes at the time of South Pole backscatter, similar features are present at earlier and later times, adjacent frequencies, and in left circular polarization. If enhanced backscatter is present, it is not unique to the South Pole; if not unique to the Pole, then ice is less likely as an explanation for the enhancement.

  16. Ancient multiring basins on the moon revealed by clementine laser altimetry.

    PubMed

    Spudis, P D; Gillis, J J; Reisse, R A

    1994-12-16

    Analysis of laser altimetry data from Clementine has confirmed and extended our knowledge of nearly obliterated multiring basins on the moon. These basins were formed during the early bombardment phase of lunar history, have been filled to varying degrees by mare lavas and regional ejecta blankets, and have been degraded by the superposition of large impact craters. The Mendel-Rydberg Basin, a degraded three-ring feature over 600 kilometers in diameter on the lunar western limb, is about 6 kilometers deep from rim to floor, only slightly less deep than the nearby younger and much better preserved Orientale Basin (8 kilometers deep). The South Pole-Aitken Basin, the oldest discernible impact feature on the moon, is revealed as a basin 2500 kilometers in diameter with an average depth of more than 13 kilometers, rim crest to floor. This feature is the largest, deepest impact crater yet discovered in the solar system. Several additional depressions seen in the data may represent previously unmapped ancient impact basins.

  17. Thermal design verification testing of the Clementine spacecraft: Quick, cheap, and useful

    NASA Technical Reports Server (NTRS)

    Kim, Jeong H.; Hyman, Nelson L.

    1994-01-01

    At this writing, Clementine had successfully fulfilled its moon-mapping mission; at this reading it will have also, with continued good fortune, taken a close look at the asteroid Geographos. The thermal design that made all this possible was indeed formidable in many respects, with very high ratios of requirements-to-available resources and performance-to-cost and mass. There was no question that a test verification of this quite unique and complex design was essential, but it had to be squeezed into an unyielding schedule and executed with bare-bones cost and manpower. After describing the thermal control subsystem's features, we report all the drama, close-calls, and cost-cutting, how objectives were achieved under severe handicap but (thankfully) with little management and documentation interference. Topics include the newly refurbished chamber (ready just in time), the reality level of the engineering model, using the analytical thermal model, the manner of environment simulation, the hand-scratched film heaters, functioning of all three types of heat pipes (but not all heat pipes), and the BMDO sensors' checkout through the chamber window. Test results revealed some surprises and much valuable data, resulting in thermal model and flight hardware refinements. We conclude with the level of correlation between predictions and both test temperatures and flight telemetry.

  18. Ancient Multiring Basins on the Moon Revealed by Clementine Laser Altimetry

    NASA Astrophysics Data System (ADS)

    Spudis, Paul D.; Reisse, Robert A.; Gillis, Jeffrey J.

    1994-12-01

    Analysis of laser altimetry data from Clementine has confirmed and extended our knowledge of nearly obliterated multiring basins on the moon. These basins were formed during the early bombardment phase of lunar history, have been filled to varying degrees by mare lavas and regional ejecta blankets, and have been degraded by the superposition of large impact craters. The Mendel-Rydberg Basin, a degraded three-ring feature over 600 kilometers in diameter on the lunar western limb, is about 6 kilometers deep from rim to floor, only slightly less deep than the nearby younger and much better preserved Orientale Basin (8 kilometers deep). The South Pole-Aitken Basin, the oldest discernible impact feature on the moon, is revealed as a basin 2500 kilometers in diameter with an average depth of more than 13 kilometers, rim crest to floor. This feature is the largest, deepest impact crater yet discovered in the solar system. Several additional depressions seen in the data may represent previously unmapped ancient impact basins.

  19. Comparative life-history traits of three phytoseiid mites associated with Tetranychus urticae (Acari: Tetranychidae) colonies in clementine orchards in eastern Spain: implications for biological control.

    PubMed

    Abad-Moyano, Raquel; Pina, Tatiana; Ferragut, Francisco; Urbaneja, Alberto

    2009-02-01

    The management of Tetranychus urticae, a key pest of clementine trees, is mainly based on the use of acaricides. However, more environmentally safe measures, such as biological control, are being encouraged. Life-history traits of the three most abundant phytoseiid mites associated with T. urticae on this crop (Euseius stipulatus, Phytoseiulus persimilis and Neoseiulus californicus) were studied. The experiments were performed under laboratory conditions (25 degrees C, 80 +/- 5% RH and 16:8 h (L:D)) on clementine leaves and T. urticae as prey. Euseius stipulatus could not complete its life cycle, whereas P. persimilis and N. californicus completed it satisfactorily. The estimated intrinsic rate of increase (rm) was significantly higher for P. persimilis (0.344 day(-1)) than for N. californicus (0.244 day(-1)) and both were higher than the rm value of T. urticae on clementine leaves. Implications of these results for the biological control of T. urticae in this crop are discussed.

  20. Effects of Euseius stipulatus on establishment and efficacy in spider mite suppression of Neoseiulus californicus and Phytoseiulus persimilis in clementine.

    PubMed

    Abad-Moyano, Raquel; Urbaneja, Alberto; Hoffmann, Daniela; Schausberger, Peter

    2010-04-01

    The two-spotted spider mite, Tetranychus urticae, is one of the most problematic phytophagous pests in Spanish clementine orchards. The most abundant predatory mites in this ecosystem are Euseius stipulatus, Phytoseiulus persimilis and Neoseiulus californicus. Euseius stipulatus is dominant but poorly adapted to utilize T. urticae as prey. It mainly persists on pollen and citrus red mite, Panonychus citri. A recent study suggested that the more efficacious T. urticae predators P. persimilis and N. californicus are negatively affected by lethal and non-lethal intraguild interactions with E. stipulatus. Here, we investigated the potential of N. californicus and P. persimilis to colonize and thrive on young clementine trees infested by T. urticae in presence and absence of E. stipulatus. Presence of E. stipulatus interfered with establishment and abundance of P. persimilis and negatively affected the efficacy of N. californicus in T. urticae suppression. In contrast, the abundance of E. stipulatus was not affected by introduction of a second predator. Trait-mediated effects of E. stipulatus changing P. persimilis and N. californicus behavior and/or life history were the most likely explanations for these outcomes. We conclude that superiority of E. stipulatus in intraguild interactions may indeed contribute to the currently observed predator species composition and abundance, rendering natural control of T. urticae in Spanish clementine orchards unsatisfactory. Nonetheless, stronger reduction of T. urticae and/or plant damage in the predator combination treatments as compared to E. stipulatus alone indicates the possibility to improve T. urticae control via repeated releases of N. californicus and/or P. persimilis.

  1. Histological and molecular analysis of pollen-pistil interaction in clementine.

    PubMed

    Distefano, Gaetano; Caruso, Marco; La Malfa, Stefano; Gentile, Alessandra; Tribulato, Eugenio

    2009-09-01

    In contrast to model species, the self-incompatibility reaction in citrus has been poorly studied. It is assumed to be gametophytically determined and genetically controlled by the S-locus, which in other species encodes for glycoproteins (S-RNases) showing ribonuclease activity. To investigate pollen-pistil interaction, the pollen tube growth of two clementine varieties, 'Comune' (self-incompatible) and 'Monreal' (a 'Comune' self-compatible mutation) was analysed by histological assays in self- and cross-pollination conditions. Cross-pollination assays demonstrated that the mutation leading to self-compatibility in 'Monreal' occurred in the stylar tissues. Similar rates of pollen germination were observed in both genotypes. However, 'Comune' pollen tubes showed altered morphology and arrested growth in the upper style while in 'Monreal' they grew straight toward the ovary. Moreover, to identify genes putatively involved in pollen-pistil interaction and self-incompatibility, research based on the complementary DNA-amplified fragment length polymorphism technique was carried out to compare the transcript profiles of unpollinated and self-pollinated styles and stigmas of the two cultivars. This analysis identified 96 unigenes such as receptor-like kinases, stress-induced genes, transcripts involved in the phenylpropanoid pathway, transcription factors and genes related to calcium and hormone signalling. Surprisingly, a high percentage of active long terminal repeat (LTR) and non-LTR retrotransposons were identified among the unigenes, indicating their activation in response to pollination and their possible role in the regulation of self-incompatibility genes. The quantitative reverse trascription-polymerase chain reaction analysis of selected gene tags showed transcriptional differences between the two genotypes during pollen germination and pollen tube elongation.

  2. Altered sensitivity to ethylene in 'Tardivo', a late-ripening mutant of Clementine mandarin.

    PubMed

    Alós, Enriqueta; Distefano, Gaetano; Rodrigo, María Jesús; Gentile, Alessandra; Zacarías, Lorenzo

    2014-08-01

    'Tardivo' mandarin is a mutant of 'Comune' Clementine with a delay in peel degreening and coloration, allowing late harvesting. In this work, we have explored if the late-harvesting phenotype of 'Tardivo' mandarin is related to altered perception and sensitivity to ethylene. The peel degreening rate was examined after a single ethephon treatment or during a continuous ethylene application in fruits at two maturation stages. In general, ethylene-induced peel degreening was considerably delayed and reduced in fruits of 'Tardivo', as well as the concomitant reduction of chlorophyll (Chl) and chloroplastic carotenoids, and the accumulation of chromoplastic carotenoids. Analysis of the expression of genes involved in Chl degradation, carotenoids, ABA, phenylpropanoids and ethylene biosynthesis revealed an impairment in the stimulation of most genes by ethylene in the peel of 'Tardivo' fruits with respect to 'Comune', especially after 5 days of ethylene application. Moreover, ethylene-induced expression of two ethylene receptor genes, ETR1 and ETR2, was also reduced in mutant fruits. Expression levels of two ethylene-responsive factors, ERF1 and ERF2, which were repressed by ethylene, were also impaired to a different extent, in fruits of both genotypes. Collectively, results suggested an altered sensitivity of the peel of 'Tardivo' to ethylene-induced physiological and molecular responses, including fruit degreening and coloration processes, which may be time-dependent since an early moderated reduction in the responses was followed by the latter inability to sustain ethylene action. These results support the involvement of ethylene in the regulation of at least some aspects of peel maturation in the non-climacteric citrus fruit.

  3. Compositional analyses of small lunar pyroclastic deposits using Clementine multispectral data

    NASA Astrophysics Data System (ADS)

    Gaddis, Lisa R.; Hawke, B. Ray; Robinson, Mark S.; Coombs, Cassandra

    2000-02-01

    Clementine ultraviolet-visible (UVVIS) data are used to examine the compositions of 18 pyroclastic deposits (15 small, three large) at 13 sites on the Moon. Compositional variations among pyroclastic deposits largely result from differing amounts of new basaltic (or juvenile) material and reworked local material entrained in their ejecta upon eruption. Characterization of pyroclastic deposit compositions allows us to understand the mechanisms of lunar explosive volcanism. Evidence for compositional differences between small pyroclastic deposits at a single site is observed at Atlas crater. At all sites, compositional variation among the small pyroclastic deposits is consistent with earlier classification based on Earth-based spectra: three compositional groups can be observed, and the trend of increasing mafic absorption band strength from Group 1 to Group 2 to Group 3 is noted. As redefined here, Group 1 deposits include those of Alphonsus West, Alphonsus Southeast, Alphonsus Northeast 2, Atlas South, Crüger, Franklin, Grimaldi, Lavoisier, Oppenheimer, Orientale, and Riccioli. Group 1 deposits resemble lunar highlands, with weak mafic bands and relatively high UV/VIS ratios. Group 2 deposits include those of Alphonsus Northeast 1, Atlas North, Eastern Frigoris East and West, and Aristarchus Plateau; Group 2 deposits are similar to mature lunar maria, with moderate mafic band depths and intermediate UV/VIS ratios. The single Group 3 deposit, J. Herschel, has a relatively strong mafic band and a low UV/VIS ratio, and olivine is a likely juvenile component. Two of the deposits in these groups, Orientale and Aristarchus, are large pyroclastic deposits. The third large pyroclastic deposit, Apollo 17/Taurus Littrow, has a very weak mafic band and a high UV/VIS ratio and it does not belong to any of the compositional groups for small pyroclastic deposits. The observed compositional variations indicate that highland and mare materials are also present in many large and

  4. Inventory of Multiring Basins on the Moon After the Clementine Mission

    NASA Astrophysics Data System (ADS)

    Spudis, P. D.

    1995-09-01

    Multi-ring basins (impact craters greater than 300 km in diameter, regardless of presently expressed morphology; [1, 2]) are of primary importance in the excavation and redistribution of crustal materials and serve as the loci for the accumulation of extruded lavas on the Moon. Understanding their distribution and configuration is important in order to reconstruct the basin-forming impact [2]. The Clementine mission has made the first global maps of the Moon, including altimetry from a laser ranging experiment [3, 4]. This map permits the characterization of long-wavelength topographic features of the lunar crust, including the most prominent and important features, multi-ring basins. We have now surveyed the entire Moon with laser altimetry data from Clementine and have inventoried the global basin population. Many of the most obscure and degraded basins are strikingly expressed in the topographic data. Basins such as Mendel-Rydberg, a nearly obliterated ancient basin (600 km diameter, 5 km deep) south of Orientale, displays nearly as much relief as the "pristine" Orientale basin (900 km diameter; 7 km depth) [5]. The Fecunditatis basin, an obscure quasi-circular feature south of Mare Crisium [3], displays considerable topographic prominence, including an average relief of about 5 km. However, not all of the ancient basins are so deep: the Mutus-Vlacq basin [3], south of Nectaris, is clearly visible in the altimetry [5], but is only 1 to 1.5 km deep. Other basins that appear very ill-defined in the altimetry, yet clearly are present as regional depressions include the Australe, Tranquillitatis, and Margims basins [3]. That both relatively deep and shallow basins exist on the Moon is not surprising; what is remarkable is that there is no correlation between basin depth and geologic age. Apparently, basin morphology is more dependent on local conditions (e.g., crustal thickness, lithospheric conditions at the time of impact) than age. Another unusual expression of

  5. Role of the cultivar in choosing Clementine fruits with a high level of health-promoting compounds.

    PubMed

    Milella, Luigi; Caruso, Marisa; Galgano, Fernanda; Favati, Fabio; Padula, Maria Carmela; Martelli, Giuseppe

    2011-05-25

    Thirteen cultivars and two hybrids of Clementine fruits (Citrus clementina Hort. Ex. Tan) cultivated in Italy were characterized according to pH, titratable acidity, total soluble solids, total polyphenols, carotenoids, vitamin C, hesperidin, rutin, narirutin and naringin and radical scavenging activity. The presence of rutin in Clementine fruit juice is reported for the first time here. The results indicated that all chemical parameters statistically differentiated each cultivar (P < 0.001). In particular, principal component analysis showed a clear discrimination of five cultivars from all the other varieties based on vitamin C and total polyphenols for the Caffin cultivar, which showed also the highest antioxidant activity; narirutin for the Etna hybrid cultivar; hesperidin, rutin and total soluble solids for the SRA 89 cultivar; and naringin, hesperidin and rutin for the Esbal cultivar. Moreover, the Mandalate hybrid cultivar showed the lowest antioxidant activity as well as vitamin C and total polyphenols content, while titratable acidity and naringin level were the highest. The antioxidant activity assessed in all the fruits was closely correlated with vitamin C and total polyphenols content, rather than with the flavonoid compounds.

  6. Assessment of Navel Oranges, Clementine Tangerines, and Rutaceous Fruits as Hosts of Bactrocera cucurbitae and Bactrocera latifrons (Diptera: Tephritidae)

    PubMed Central

    McQuate, Grant T.; Follett, Peter A.; Liquido, Nicanor J.; Sylva, Charmaine D.

    2015-01-01

    Export of Citrus spp. fruits may require risk mitigation measures if grown in areas with established tephritid fruit fly (Diptera: Tephritidae) populations capable of infesting the fruits. The host status of Citrus spp. fruits is unclear for two tephritid fruit fly species whose geographic ranges have expanded in recent years: melon fly, Bactrocera cucurbitae (Cocquillett), and Bactrocera latifrons (Hendel). In no choice cage infestation studies, B. latifrons oviposited into intact and punctured Washington navel oranges (Citrus sinensis [L.] Osbeck) and Clementine tangerines (C. reticulata L. var. Clementine), but eggs rarely developed to the adult stage. B. cucurbitae readily infested intact and punctured tangerines, and to a lesser extent punctured oranges, but did not infest intact oranges. Limited cage infestation and only a single literature report of field Citrus spp. infestation suggest that risk mitigation of Citrus spp. for B. latifrons is not needed. Risk mitigation options of Citrus spp. for B. cucurbitae, including heat and cold treatments and systems approaches, are discussed. PMID:26816484

  7. Assessment of Navel Oranges, Clementine Tangerines, and Rutaceous Fruits as Hosts of Bactrocera cucurbitae and Bactrocera latifrons (Diptera: Tephritidae).

    PubMed

    McQuate, Grant T; Follett, Peter A; Liquido, Nicanor J; Sylva, Charmaine D

    2015-01-01

    Export of Citrus spp. fruits may require risk mitigation measures if grown in areas with established tephritid fruit fly (Diptera: Tephritidae) populations capable of infesting the fruits. The host status of Citrus spp. fruits is unclear for two tephritid fruit fly species whose geographic ranges have expanded in recent years: melon fly, Bactrocera cucurbitae (Cocquillett), and Bactrocera latifrons (Hendel). In no choice cage infestation studies, B. latifrons oviposited into intact and punctured Washington navel oranges (Citrus sinensis [L.] Osbeck) and Clementine tangerines (C. reticulata L. var. Clementine), but eggs rarely developed to the adult stage. B. cucurbitae readily infested intact and punctured tangerines, and to a lesser extent punctured oranges, but did not infest intact oranges. Limited cage infestation and only a single literature report of field Citrus spp. infestation suggest that risk mitigation of Citrus spp. for B. latifrons is not needed. Risk mitigation options of Citrus spp. for B. cucurbitae, including heat and cold treatments and systems approaches, are discussed. PMID:26816484

  8. A Hybrid Method for Calculating TiO2 Concentrations Using Clementine UVVIS Data, and Verified with Lunar Prospector Neutron Spectrometer Data

    NASA Technical Reports Server (NTRS)

    Gillis, J. J.; Jolliff, B. L.; Elphic, R. C.; Maurice, S.; Feldman, W. C.; Lawrence, D. J.

    2001-01-01

    We present a new algorithm for extracting TiO2 concentrations from Clementine UVVIS data, which accounts for soil darkness and UV/VIS ratio. The accuracy of these TiO2 estimates are examined with Lunar Prospector thermal/epithermal neutron flux data. Additional information is contained in the original extended abstract.

  9. Clementine Observations of the Zodiacal Light and the Dust Content of the Inner Solar System

    NASA Technical Reports Server (NTRS)

    Hahn, Joseph M.; Zook, Herbert A.; Cooper, Bonnie; Sunkara, Bhaskar

    2002-01-01

    Using the Moon to occult the Sun, the Clementine spacecraft used its navigation cameras to map the inner zodiacal light at optical wavelengths over elongations of 3 approx. less than epsilon approx. less than 30 deg from the Sun. This surface brightness map is then used to infer the spatial distribution of interplanetary dust over heliocentric distances of about 10 solar radii to the orbit of Venus. The averaged ecliptic surface brightness of the zodiacal light falls off as Z(epsilon) is a member of epsilon(sup -2.45 +/- 0.05), which suggests that the dust cross-sectional density nominally falls off as sigma(r) is a member of r(sup - 1.45 +/- 0.05). The interplanetary dust also has an albedo of alpha approx. = 0.1 that is uncertain by a factor of approx. 2. Asymmetries of approx. 10% are seen in directions east-west and north-south of the Sun, and these may be due the giant planets' secular gravitational perturbations. We apply a simple model that attributes the zodiacal light as due to three dust populations having distinct inclination distributions, namely, dust from asteroids and Jupiter-family comets (JFCs) having characteristic inclinations of i approx. 7 deg, dust from Halley-type comets having i approx. 33 deg, and an isotropic cloud of dust from Oort Cloud comets. The best-fitting scenario indicates that asteroids + JFCs are the source of about 45% of the optical dust cross section seen in the ecliptic at 1 AU but that at least 89% of the dust cross section enclosed by a 1-AU-radius sphere is of a cometary origin. Each population's radial density variations can also deviate somewhat from the nominal sigma(r) is a member of r(sup -1.45). When these results are extrapolated out to the asteroid belt, we find an upper limit on the mass of the light-reflecting asteroidal dust that is equivalent to a 12-km asteroid, and a similar extrapolation of the isotropic dust cloud out to Oort Cloud distances yields a mass equivalent to a 30-km comet, although the latter

  10. Compositional analyses of small lunar pyroclastic deposits using Clementine multispectral data

    USGS Publications Warehouse

    Gaddis, L.R.; Hawke, B.R.; Robinson, M.S.; Coombs, C.

    2000-01-01

    Clementine ultraviolet-visible (UVVIS) data are used to examine the compositions of 18 pyroclastic deposits (15 small, three large) at 13 sites on the Moon. Compositional variations among pyroclastic deposits largely result from differing amounts of new basaltic (or juvenile) material and reworked local material entrained in their ejecta upon eruption. Characterization of pyroclastic deposit compositions allows us to understand the mechanisms of lunar explosive volcanism. Evidence for compositional differences between small pyroclastic deposits at a single site is observed at Atlas crater. At all sites, compositional variation among the small pyroclastic deposits is consistent with earlier classification based on Earth-based spectra: three compositional groups can be observed, and the trend of increasing mafic absorption band strength from Group 1 to Group 2 to Group 3 is noted. As redefined here, Group 1 deposits include those of Alphonsus West, Alphonsus Southeast, Alphonsus Northeast 2, Atlas South, Crüger, Franklin, Grimaldi, Lavoisier, Oppenheimer, Orientale, and Riccioli. Group 1 deposits resemble lunar highlands, with weak mafic bands and relatively high UV/VIS ratios. Group 2 deposits include those of Alphonsus Northeast 1, Atlas North, Eastern Frigoris East and West, and Aristarchus Plateau; Group 2 deposits are similar to mature lunar maria, with moderate mafic band depths and intermediate UV/VIS ratios. The single Group 3 deposit, J. Herschel, has a relatively strong mafic band and a low UV/VIS ratio, and olivine is a likely juvenile component. Two of the deposits in these groups, Orientale and Aristarchus, are large pyroclastic deposits. The third large pyroclastic deposit, Apollo 17/Taurus Littrow, has a very weak mafic band and a high UV/VIS ratio and it does not belong to any of the compositional groups for small pyroclastic deposits. The observed compositional variations indicate that highland and mare materials are also present in many large and

  11. Self-pollination and parthenocarpic ability in developing ovaries of self-incompatible Clementine mandarins (Citrus clementina).

    PubMed

    Mesejo, Carlos; Yuste, Roberto; Martínez-Fuentes, Amparo; Reig, Carmina; Iglesias, Domingo J; Primo-Millo, Eduardo; Agustí, Manuel

    2013-05-01

    This study aimed to determine if self-pollination is needed to trigger facultative parthenocarpy in self-incompatible Clementine mandarins (Citrus clementina Hort. ex Tan.). 'Marisol' and 'Clemenules' mandarins were selected, and self-pollinated and un-pollinated flowers from both cultivars were used for comparison. These mandarins are always seedless after self-pollination and show high and low ability to develop substantial parthenocarpic fruits, respectively. The time-course for pollen grain germination, tube growth and ovule abortion was analyzed as well as that for carbohydrates, active gibberellins (GA1 and GA4 ), auxin (IAA) and abscisic acid (ABA) content in the ovary. 'Clemenules' showed higher pollen grain germination, but pollen tube development was arrested in the upper style 9 days after pollination in both cultivars. Self-pollination did not stimulate parthenocarpy, whereas both un-pollinated and self-pollinated ovaries set fruit regardless of the cultivar. On the other hand, 'Marisol' un-pollinated flowers showed greater parthenocarpic ovary growth than 'Clemenules' un-pollinated flowers, i.e. higher ovule abortion rate (+21%), higher fruit set (+44%) and higher fruit weight (+50%). Further, the greater parthenocarpic ability of 'Marisol' paralleled higher levels of GA1 in the ovary (+34% at anthesis). 'Marisol' ovary also showed higher hexoses and starch mobilization, but lower ABA levels (-64% at anthesis). Self-pollination did not modify carbohydrates or GA content in the ovary compared to un-pollination. Results indicate that parthenocarpy in the Clementine mandarin is pollination-independent with its ability to set depending on the ovary hormone levels. These findings suggest that parthenocarpy in fertile self-incompatible mandarins is constitutively regulated.

  12. Self-pollination and parthenocarpic ability in developing ovaries of self-incompatible Clementine mandarins (Citrus clementina).

    PubMed

    Mesejo, Carlos; Yuste, Roberto; Martínez-Fuentes, Amparo; Reig, Carmina; Iglesias, Domingo J; Primo-Millo, Eduardo; Agustí, Manuel

    2013-05-01

    This study aimed to determine if self-pollination is needed to trigger facultative parthenocarpy in self-incompatible Clementine mandarins (Citrus clementina Hort. ex Tan.). 'Marisol' and 'Clemenules' mandarins were selected, and self-pollinated and un-pollinated flowers from both cultivars were used for comparison. These mandarins are always seedless after self-pollination and show high and low ability to develop substantial parthenocarpic fruits, respectively. The time-course for pollen grain germination, tube growth and ovule abortion was analyzed as well as that for carbohydrates, active gibberellins (GA1 and GA4 ), auxin (IAA) and abscisic acid (ABA) content in the ovary. 'Clemenules' showed higher pollen grain germination, but pollen tube development was arrested in the upper style 9 days after pollination in both cultivars. Self-pollination did not stimulate parthenocarpy, whereas both un-pollinated and self-pollinated ovaries set fruit regardless of the cultivar. On the other hand, 'Marisol' un-pollinated flowers showed greater parthenocarpic ovary growth than 'Clemenules' un-pollinated flowers, i.e. higher ovule abortion rate (+21%), higher fruit set (+44%) and higher fruit weight (+50%). Further, the greater parthenocarpic ability of 'Marisol' paralleled higher levels of GA1 in the ovary (+34% at anthesis). 'Marisol' ovary also showed higher hexoses and starch mobilization, but lower ABA levels (-64% at anthesis). Self-pollination did not modify carbohydrates or GA content in the ovary compared to un-pollination. Results indicate that parthenocarpy in the Clementine mandarin is pollination-independent with its ability to set depending on the ovary hormone levels. These findings suggest that parthenocarpy in fertile self-incompatible mandarins is constitutively regulated. PMID:23002897

  13. Integration and Comparison of Clementine and Lunar Prospector Data: Global Scale Multielement Analysis1 (Fe, Ti, and Th) of the Lunar Surface

    NASA Astrophysics Data System (ADS)

    Chevrel, S. D.; Pinet, P. C.; Daydou, Y.; Feldman, W. C.

    2002-11-01

    In this paper, we present (1) a statistical analysis, based on a systematic clustering method, of a dataset integrating the global abundance maps of the three elements iron, titanium, and thorium derived from Clementine and Lunar Prospector and (2) a comparison of iron abundances between Clementine and Lunar Prospector. Homogeneous geologic units are compositionally characterized and spatially defined in relation to the major rock types sampled on the Moon. With the lowest abundances of Fe, Ti, and Th found on the Moon, the lunar highland terrains are quite homogeneous with two major large feldspathic units, one being slightly more mafic than the other. Two distinct regions with unique compositions are unambiguously identified: the Procellarum KREEP Terrane (PKT) and the South Pole-Aitken (SPA). The PKT, which includes all the units with Th abundances higher than 3.5 ppm (KREEP-rich materials), is delimited by an almost continuous ringlike unit. In particular, it includes the western nearside maria, except for Mare Humorum. With concentrations in Fe, Ti, and Th enhanced relative to the surrounding highlands, the South Pole-Aitken basin floor represents a large mafic anomaly on the far side, suggesting wide deposits of lower crust and possible mantle materials. However, due to indirect residual latitude effects in the CSR (Clementine spectral reflectance) measurements, iron abundances might have been overestimated in SPA, thus implying that crustal materials, rather than mantle materials, might represent the dominant contributor to the mafic component exposed on the basin floor.

  14. Asymmetric reduction of ketones by biocatalysis using clementine mandarin (Citrus reticulata) fruit grown in Annaba or by ruthenium catalysis for access to both enantiomers.

    PubMed

    Bennamane, Manhel; Zeror, Saoussen; Aribi-Zouioueche, Louisa

    2015-03-01

    Biocatalytic reduction of prochiral ketones using freshly ripened clementine mandarin (Citrus reticulata) in aqueous medium is reported. High enantioselectivities were observed, especially for the bioreduction of indanone , tetralone , and thiochromanone with respectively 95%, 99%, and 86% enantiomeric excess (ee). Enantioselective bio- and metal-catalyzed reactions were compared. Chiral ruthenium catalysts afforded good asymmetric inductions (>75% ee) in most cases, enantiomeric excesses depending on the nature of substrate and ligand. N-aminoindanol prolinamide was revealed as the best ligand for most ketones. Interestingly, for several substrates both enantiomers could be obtained using either Citrus reticulata or ruthenium complex.

  15. Asymmetric reduction of ketones by biocatalysis using clementine mandarin (Citrus reticulata) fruit grown in Annaba or by ruthenium catalysis for access to both enantiomers.

    PubMed

    Bennamane, Manhel; Zeror, Saoussen; Aribi-Zouioueche, Louisa

    2015-03-01

    Biocatalytic reduction of prochiral ketones using freshly ripened clementine mandarin (Citrus reticulata) in aqueous medium is reported. High enantioselectivities were observed, especially for the bioreduction of indanone , tetralone , and thiochromanone with respectively 95%, 99%, and 86% enantiomeric excess (ee). Enantioselective bio- and metal-catalyzed reactions were compared. Chiral ruthenium catalysts afforded good asymmetric inductions (>75% ee) in most cases, enantiomeric excesses depending on the nature of substrate and ligand. N-aminoindanol prolinamide was revealed as the best ligand for most ketones. Interestingly, for several substrates both enantiomers could be obtained using either Citrus reticulata or ruthenium complex. PMID:25482318

  16. Clementine High Resolution Camera Mosaicking Project. Volume 6; CL 6006; 80 deg N to 80 deg S Latitude, 90 deg E to 120 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  17. Clementine High Resolution Camera Mosaicking Project. Volume 7; CL 6007; 80 deg N to 80 deg S Latitude, 120 deg E to 150 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  18. Clementine High Resolution Camera Mosaicking Project. Volume 18; CL 6018; 80 deg N to 80 deg S Latitude, 330 deg E to 360 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U. S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  19. Clementine High Resolution Camera Mosaicking Project. Volume 5; CL 6005, 80 deg N to 80 deg S Latitude, 60 deg E to 90 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  20. Clementine High Resolution Camera Mosaicking Project. Volume 3; CL 6003; 0 deg N to 80 deg N Latitude, 30 deg E to 60 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  1. Clementine High Resolution Camera Mosaicking Project. Volume 16; CL 6016; 0 deg N to 80 deg N Latitude, 300 deg E to 330 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  2. Clementine High Resolution Camera Mosaicking Project. Volume 1; CL 6001; 0 deg N to 80 deg N Latitude, 0 deg E to 30 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  3. Clementine High Resolution Camera Mosaicking Project. Volume 7; CL 6007; 80 deg N to 80 deg S Latitude; 120 deg E to 150 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  4. Clementine High Resolution Camera Mosaicking Project. Volume 14; CL 6014; 0 deg N to 80 deg N Latitude, 270 deg E to 300 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  5. Clementine High Resolution Camera Mosaicking Project. Volume 2; CL 6002; 0 deg S to 80 deg S Latitude, 0 deg E to 30 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  6. Clementine High Resolution Camera Mosaicking Project. Volume 9; CL 6009; 80 deg N to 80 deg S Latitude, 180 deg to 210 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  7. Clementine High Resolution Camera Mosaicking Project. Volume 13; CL 6013; 0 deg S to 80 deg S Latitude, 240 deg to 270 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  8. Clementine High Resolution Camera Mosaicking Project. Volume 10; CL 6010; 0 deg N to 80 deg N Latitude, 210 deg E to 240 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  9. Clementine High Resolution Camera Mosaicking Project. Volume 12; CL 6012; 0 deg N to 80 deg N Latitude, 240 deg to 270 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  10. Clementine High Resolution Camera Mosaicking Project. Volume 17; CL 6017; 0 deg to 80 deg S Latitude, 330 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  11. Clementine High Resolution Camera Mosaicking Project. Volume 4; CL 6004; 0 deg S to 80 deg S Latitude, 30 deg E to 60 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U.S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  12. Clementine High Resolution Camera Mosaicking Project. Volume 15; CL 6015; 0 deg S to 80 deg S Latitude, 270 deg E to 300 deg E Longitude; 1

    NASA Technical Reports Server (NTRS)

    Malin, Michael; Revine, Michael; Boyce, Joseph M. (Technical Monitor)

    1998-01-01

    This compact disk (CD) is part of the Malin Space Science Systems (MSSS) effort to mosaic Clementine I high resolution (HiRes) camera lunar images. These mosaics were developed through calibration and semi-automated registration against the recently released geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic, which is available through the PDS, as CD-ROM volumes CL_3001-3015. The HiRes mosaics are compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution observations from the HiRes imaging system onboard the Clementine Spacecraft. These mosaics are spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel. The geometric control is provided by the 100 m/pixel U. S. Geological Survey (USGS) Clementine Basemap Mosaic compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Calibration was achieved by removing the image nonuniformity largely caused by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap that approximately transform the 8-bit HiRes data to photometric units. The mosaics on this CD were compiled from sub-polar data (latitudes 80 degrees South to 80 degrees North; -80 to +80) within the longitude range 0-30 deg E. The mosaics are divided into tiles that cover approximately 1.75 degrees of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. This CD contains ancillary data files that support the HiRes mosaic. These files include browse images with UV/Vis context stored in a Joint Photographic Experts Group (JPEG) format, index files ('imgindx.tab' and 'srcindx.tab') that tabulate the contents of the CD, and documentation files. For more information on the contents and organization of the CD volume set refer to the "FILES

  13. Degradation of imazalil, orthophenylphenol and pyrimethanil in Clementine mandarins under conventional postharvest industrial conditions at 4°C.

    PubMed

    Besil, Natalia; Pérez-Parada, Andrés; Cesio, Verónica; Varela, Pablo; Rivas, Fernando; Heinzen, Horacio

    2016-03-01

    The degradation of the postharvest fungicides imazalil, orthophenylphenol, and pyrimethanil was studied on Clementine mandarins during packinghouse storage for a 28day period at 4°C. Fruits to which orthophenylphenol was applied, were treated with imazalil and pyrimethanil at doses of 1000 and 2000mgL(-1), using cascade application for the later and cascade and wax for the former. The decay of the three fungicides was evaluated using an in-house validated analytical procedure that includes the extraction and dispersive clean up of the samples followed by the GC-MS determination of the pesticide residues. The impact of fruit storage time on pesticide residues concentration was assessed. The residues found for the different application technologies were always below the established Maximum Residue Limits by the Codex Alimentarius and the European Union (5mgkg(-1) for imazalil, 7 and 8mgkg(-1) for pyrimethanil, and 10mgkg(-1) and 5mgkg(-1) for orthophenylphenol). The fungicides dissipated differentially. Pyrimethanil showed little degradation, if any, at both tested concentrations, but the half-life of imazalil on the fruit was 15-18days, independent of the application technology. Orthophenylphenol dissipated with a half-life of 15days. The initial imazalil residue found after cascade treatment was not significantly different between the doses studied (p<0.5), whereas when the fungicide was included in wax as an emulsifiable concentrate the initial and final imazalil residues were significantly different. Final residue levels after 28days of storage were 0.12-0.24mgkg(-1) for imazalil, 0.68mgkg(-1) for 2-phenylphenol and 0.56mgkg(-1) for pyrimethanil for all the evaluated treatments.

  14. Degradation of imazalil, orthophenylphenol and pyrimethanil in Clementine mandarins under conventional postharvest industrial conditions at 4°C.

    PubMed

    Besil, Natalia; Pérez-Parada, Andrés; Cesio, Verónica; Varela, Pablo; Rivas, Fernando; Heinzen, Horacio

    2016-03-01

    The degradation of the postharvest fungicides imazalil, orthophenylphenol, and pyrimethanil was studied on Clementine mandarins during packinghouse storage for a 28day period at 4°C. Fruits to which orthophenylphenol was applied, were treated with imazalil and pyrimethanil at doses of 1000 and 2000mgL(-1), using cascade application for the later and cascade and wax for the former. The decay of the three fungicides was evaluated using an in-house validated analytical procedure that includes the extraction and dispersive clean up of the samples followed by the GC-MS determination of the pesticide residues. The impact of fruit storage time on pesticide residues concentration was assessed. The residues found for the different application technologies were always below the established Maximum Residue Limits by the Codex Alimentarius and the European Union (5mgkg(-1) for imazalil, 7 and 8mgkg(-1) for pyrimethanil, and 10mgkg(-1) and 5mgkg(-1) for orthophenylphenol). The fungicides dissipated differentially. Pyrimethanil showed little degradation, if any, at both tested concentrations, but the half-life of imazalil on the fruit was 15-18days, independent of the application technology. Orthophenylphenol dissipated with a half-life of 15days. The initial imazalil residue found after cascade treatment was not significantly different between the doses studied (p<0.5), whereas when the fungicide was included in wax as an emulsifiable concentrate the initial and final imazalil residues were significantly different. Final residue levels after 28days of storage were 0.12-0.24mgkg(-1) for imazalil, 0.68mgkg(-1) for 2-phenylphenol and 0.56mgkg(-1) for pyrimethanil for all the evaluated treatments. PMID:26471663

  15. Intraguild interactions between Euseius stipulatus and the candidate biocontrol agents of Tetranychus urticae in Spanish clementine orchards: Phytoseiulus persimilis and Neoseiulus californicus.

    PubMed

    Abad-Moyano, Raquel; Urbaneja, Alberto; Schausberger, Peter

    2010-01-01

    Spanish clementine orchards are frequently infested by the two-spotted spider mte Tetranychus urticae. Natural control of T. urticae is insufficient despite the presence of Neoseiulus californicus and Phytoseiulus persimilis. The phytoseiid community is dominated by the generalist Euseius stipulatus which is poorly adapted to exploit T. urticae. Having the intention to promote biological control of T. urticae by augmentative releases we were interested whether P. persimilis and N. californicus are negatively affected by intraguild (IG) interactions with E. stipulatus. Two experiments were conducted. Firstly, we assessed female aggressiveness (quantified as combination of attack probability and latency) in IG predation on larvae. Secondly, we measured mortality, escaping rate and developmental time of immature IG prey in presence and absence of an adult IG predator female. Euseius stipulatus appeared the strongest IG opponent but microhabitat structure modulated the IG interactions and the advantage of E. stipulatus was partially offset when spider mite webbing was present. Implications of these IG interactions for natural and biological control of T. urticae in clementine orchards are discussed.

  16. Physiological and molecular analysis of the maturation process in fruits of Clementine Mandarin and one of its late-ripening mutants.

    PubMed

    Distefano, Gaetano; Las Casas, Giuseppina; Caruso, Marco; Todaro, Aldo; Rapisarda, Paolo; La Malfa, Stefano; Gentile, Alessandra; Tribulato, Eugenio

    2009-09-01

    Peel color is one of the main features affecting citrus quality. Clementine is a widespread citrus species with several mutants showing a delay in pigmentation and harvesting. This work characterizes the fruit development and ripening of two clementine clones, 'Comune', a widespread variety, and one of its natural mutations, 'Tardivo', which differ by a delayed color-break and extended harvest period. Morphological, chemical, and molecular analyses were carried out on fruits of both genotypes during the whole maturation process. Analysis showed that mutation did not affect ripening characteristics such as juice acidity and TSS. However, biochemical and molecular analysis revealed marked differences in the flavedo regarding carotenogenesis and chlorophyllase gene expression. Carotenoid showed quantitative differences at biochemical and molecular levels. Results demonstrated that the mutation in 'Tardivo' influenced the transcriptional activation of PSY, a key step in carotenoid biosynthesis. The differential PSY expression led to a significant quantitative difference in phytoene accumulation between the two genotypes. Also, 'Tardivo' showed delayed accumulation of carotenes, lutein, and beta,beta-xanthophylls. The differential expression of genes involved in ethylene biosynthesis and perception suggested differing responses to ethylene signaling between the two genotypes. Moreover, exogenous application of ethylene revealed a different sensitivity of the two varieties to this hormone. The analysis added new information to better understand the complex process of ripening in citrus.

  17. Physiological and molecular analysis of the maturation process in fruits of Clementine Mandarin and one of its late-ripening mutants.

    PubMed

    Distefano, Gaetano; Las Casas, Giuseppina; Caruso, Marco; Todaro, Aldo; Rapisarda, Paolo; La Malfa, Stefano; Gentile, Alessandra; Tribulato, Eugenio

    2009-09-01

    Peel color is one of the main features affecting citrus quality. Clementine is a widespread citrus species with several mutants showing a delay in pigmentation and harvesting. This work characterizes the fruit development and ripening of two clementine clones, 'Comune', a widespread variety, and one of its natural mutations, 'Tardivo', which differ by a delayed color-break and extended harvest period. Morphological, chemical, and molecular analyses were carried out on fruits of both genotypes during the whole maturation process. Analysis showed that mutation did not affect ripening characteristics such as juice acidity and TSS. However, biochemical and molecular analysis revealed marked differences in the flavedo regarding carotenogenesis and chlorophyllase gene expression. Carotenoid showed quantitative differences at biochemical and molecular levels. Results demonstrated that the mutation in 'Tardivo' influenced the transcriptional activation of PSY, a key step in carotenoid biosynthesis. The differential PSY expression led to a significant quantitative difference in phytoene accumulation between the two genotypes. Also, 'Tardivo' showed delayed accumulation of carotenes, lutein, and beta,beta-xanthophylls. The differential expression of genes involved in ethylene biosynthesis and perception suggested differing responses to ethylene signaling between the two genotypes. Moreover, exogenous application of ethylene revealed a different sensitivity of the two varieties to this hormone. The analysis added new information to better understand the complex process of ripening in citrus. PMID:19655798

  18. Interactions between citrus viroids affect symptom expression and field performance of clementine trees grafted on trifoliate orange.

    PubMed

    Vernière, C; Perrier, X; Dubois, C; Dubois, A; Botella, L; Chabrier, C; Bové, J M; Vila, N Duran

    2006-04-01

    ABSTRACT Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), a noncachexia variant of Hop stunt viroid (HSVd), Citrus viroid III (CVd-III), and Citrus viroid IV (CVd-IV) were co-inoculated as two-, three-, four-, and five-viroid mixtures to Clementine trees grafted on trifoliate orange to evaluate their effect on symptom expression, tree growth, and fruit yield. Most trees infected with CEVd-containing viroid mixtures developed exocortis scaling symptoms, as did CEVd alone, whereas most trees infected with HSVd- or CVd-IV-containing mixtures developed bark-cracking symptoms. Trees infected with mixtures containing both CEVd and CVd-IV revealed the existence of antagonism between these two viroids in terms of the expected bark-scaling and cracking symptoms. Synergistic interactions also were identified in trees infected with certain viroid combinations that, in spite of lacking CEVd, expressed exocortis-like scaling symptoms. Viroid interactions also affected the expected response of trees in terms of vegetative growth and fruit yield. Trees infected with viroid combinations containing CEVd or CVd-III were smaller and produced less fruit than trees infected with mixtures not containing these viroids. Viroid interactions on scion circumference and cumulative fruit yield, in terms of additivity of their effects, were statistically confirmed using a factorial analysis of variance model with two mean estimation approaches. In single-viroid infections, CEVd, CVd-III, and, to a lesser extent, CBLVd consistently and significantly reduced tree size and fruit yield. Conversely, HSVd and CVd-IV slightly increased fruit yield and reduced scion circumference. Rare and not consistent significant interactions were detected with the five-, four-, and three-viroid combinations. Antagonistic interactions between CEVd and CVd-III or CBLVd and CVd-III were revealed over the years with consistent significance. The antagonistic interaction between CEVd and CVd-IV was highly

  19. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Zinn, W.H.; Anderson, H.L.

    1958-09-16

    Means are presenied for increasing the reproduction ratio of a gaphite- moderated neutronic reactor by diminishing the neutron loss due to absorption or capture by gaseous impurities within the reactor. This means comprised of a fluid-tight casing or envelope completely enclosing the reactor and provided with a valve through which the casing, and thereby the reactor, may be evacuated of atmospheric air.

  20. Clementine Sensor Processing System

    NASA Technical Reports Server (NTRS)

    Feldstein, A. A.

    1993-01-01

    The design of the DSPSE Satellite Controller (DSC) is baselined as a single-string satellite controller. The DSC performs two main functions: health and maintenance of the spacecraft; and image capture, storage, and playback. The DSC contains two processors: a radiation-hardened Mil-Std-1750, and a commercial R3000. The Mil-Std-1750 processor performs all housekeeping operations, while the R3000 is mainly used to perform the image processing functions associated with the navigation functions, as well as performing various experiments. The DSC also contains a data handling unit (DHU) used to interface to various spacecraft imaging sensors and to capture, compress, and store selected images onto the solid-state data recorder. The development of the DSC evolved from several key requirements; the DSPSE satellite was to do the following: (1) have a radiation-hardened spacecraft control system and be immune to single-event upsets (SEU's); (2) use an R3000-based processor to run the star tracker software that was developed by SDIO (due to schedule and cost constraints, there was no time to port the software to a radiation-hardened processor); and (3) fly a commercial processor to verify its suitability for use in a space environment. In order to enhance the DSC reliability, the system was designed with multiple processing paths. These multiple processing paths provide for greater tolerance to various component failures. The DSC was designed so that all housekeeping processing functions are performed by either the Mil-Std-1750 processor or the R3000 processor. The image capture and storage is performed either by the DHU or the R3000 processor.

  1. 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.

  2. NEUTRONIC REACTOR

    DOEpatents

    Daniels, F.

    1959-10-27

    A reactor in which at least a portion of the moderator is in the form of movable refractory balls is described. In addition to their moderating capacity, these balls may serve as carriers for fissionable material or fertile material, or may serve in a coolant capacity to remove heat from the reactor. A pneumatic system is used to circulate the balls through the reactor.

  3. Research reactors

    SciTech Connect

    Tonneson, L.C.; Fox, G.J.

    1996-04-01

    There are currently 284 research reactors in operation, and 12 under construction around the world. Of the operating reactors, nearly two-thirds are used exclusively for research, and the rest for a variety of purposes, including training, testing, and critical assembly. For more than 50 years, research reactor programs have contributed greatly to the scientific and educational communities. Today, six of the world`s research reactors are being shut down, three of which are in the USA. With government budget constraints and the growing proliferation concerns surrounding the use of highly enriched uranium in some of these reactors, the future of nuclear research could be impacted.

  4. CONVECTION REACTOR

    DOEpatents

    Hammond, R.P.; King, L.D.P.

    1960-03-22

    An homogeneous nuclear power reactor utilizing convection circulation of the liquid fuel is proposed. The reactor has an internal heat exchanger looated in the same pressure vessel as the critical assembly, thereby eliminating necessity for handling the hot liquid fuel outside the reactor pressure vessel during normal operation. The liquid fuel used in this reactor eliminates the necessity for extensive radiolytic gas rocombination apparatus, and the reactor is resiliently pressurized and, without any movable mechanical apparatus, automatically regulates itself to the condition of criticality during moderate variations in temperature snd pressure and shuts itself down as the pressure exceeds a predetermined safe operating value.

  5. NEUTRONIC REACTOR

    DOEpatents

    Fraas, A.P.; Mills, C.B.

    1961-11-21

    A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)

  6. REACTOR COOLING

    DOEpatents

    Quackenbush, C.F.

    1959-09-29

    A nuclear reactor with provisions for selectively cooling the fuel elements is described. The reactor has a plurality of tubes extending throughout. Cylindrical fuel elements are disposed within the tubes and the coolant flows through the tubes and around the fuel elements. The fuel elements within the central portion of the reactor are provided with roughened surfaces of material. The fuel elements in the end portions of the tubes within the reactor are provlded with low conduction jackets and the fuel elements in the region between the central portion and the end portions are provided with smooth surfaces of high heat conduction material.

  7. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1958-04-22

    A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

  8. NEUTRONIC REACTOR

    DOEpatents

    Metcalf, H.E.; Johnson, H.W.

    1961-04-01

    BS>A nuclear reactor incorporating fuel rods passing through a moderator and including tubes of a material of higher Thermal conductivity than the fuel in contact with the fuel is described. The tubes extend beyond the active portion of the reactor into contant with a fiuld coolant.

  9. Reactor building

    SciTech Connect

    Hista, J. C.

    1984-09-18

    Reactor building comprising a vessel shaft anchored in a slab which is peripherally locked. This reactor building comprises a confinement enclosure within which are positioned internal structures constituted by an internal structure floor, a vessel shaft, a slab being positioned between the general floor and the internal structure floor, the vesse

  10. The use of Vis/NIRS and chemometric analysis to predict fruit defects and postharvest behaviour of 'Nules Clementine' mandarin fruit.

    PubMed

    Magwaza, Lembe Samukelo; Landahl, Sandra; Cronje, Paul J R; Nieuwoudt, Hélène H; Mouazen, Abdul Mounem; Nicolaï, Bart M; Terry, Leon A; Opara, Umezuruike Linus

    2014-11-15

    The use of chemometrics to analyse Vis/NIRS signal collected from intact 'Nules Clementine' mandarin fruit at harvest, to predict the rind physico-chemical profile after eight weeks postharvest was explored. Vis/NIRS signals of 150 fruit were obtained immediately after harvest. Reference data on the rind were obtained after eight-week storage, including colour index (CI), rind dry matter (DM), and concentration of sugars. Partial least squares (PLS) regression was applied to develop models. Principal component analysis (PCA) followed by PLS-discriminant analysis (PLS-DA) were used to classify fruit according to canopy position. Optimal PLS model performances for DM, sucrose, glucose and fructose were obtained using multiple scatter correction pre-processing, showing respective residual predictive deviation (RPD) of 3.39, 1.75, 2.19 and 3.08. Clusters of sample distribution in the PCA and PLS-DA models based on canopy position were obtained. The results demonstrated the potential applications of Vis/NIRS to predict postharvest behaviour of mandarin fruit.

  11. Compact Reactor

    SciTech Connect

    Williams, Pharis E.

    2007-01-30

    Weyl's Gauge Principle of 1929 has been used to establish Weyl's Quantum Principle (WQP) that requires that the Weyl scale factor should be unity. It has been shown that the WQP requires the following: quantum mechanics must be used to determine system states; the electrostatic potential must be non-singular and quantified; interactions between particles with different electric charges (i.e. electron and proton) do not obey Newton's Third Law at sub-nuclear separations, and nuclear particles may be much different than expected using the standard model. The above WQP requirements lead to a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for space power. The logic is summarized by which the WQP requires the above conditions that make the prediction of DDH possible. The details of the DDH reaction will be presented along with the specifics of why the DDH reactor may be made to cause two deuterium nuclei to preferentially fuse to a helium nucleus. The presentation will also indicate the calculations needed to predict the reactor temperature as a function of fuel loading, reactor size, and desired output and will include the progress achieved to date.

  12. NUCLEAR REACTOR

    DOEpatents

    Moore, R.V.; Bowen, J.H.; Dent, K.H.

    1958-12-01

    A heterogeneous, natural uranium fueled, solid moderated, gas cooled reactor is described, in which the fuel elements are in the form of elongated rods and are dlsposed within vertical coolant channels ln the moderator symmetrically arranged as a regular lattice in groups. This reactor employs control rods which operate in vertical channels in the moderator so that each control rod is centered in one of the fuel element groups. The reactor is enclosed in a pressure vessel which ls provided with access holes at the top to facilitate loading and unloadlng of the fuel elements, control rods and control rod driving devices.

  13. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.

    1960-04-01

    A nuclear reactor is described consisting of blocks of graphite arranged in layers, natural uranium bodies disposed in holes in alternate layers of graphite blocks, and coolant tubes disposed in the layers of graphite blocks which do not contain uranium.

  14. NEUTRONIC REACTOR

    DOEpatents

    Anderson, H.L.

    1960-09-20

    A nuclear reactor is described comprising fissionable material dispersed in graphite blocks, helium filling the voids of the blocks and the spaces therebetween, and means other than the helium in thermal conductive contact with the graphite for removing heat.

  15. Chemical Reactors.

    ERIC Educational Resources Information Center

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  16. NEUTRONIC REACTOR

    DOEpatents

    Hurwitz, H. Jr.; Brooks, H.; Mannal, C.; Payne, J.H.; Luebke, E.A.

    1959-03-24

    A reactor of the heterogeneous, liquid cooled type is described. This reactor is comprised of a central region of a plurality of vertically disposed elongated tubes surrounded by a region of moderator material. The central region is comprised of a central core surrounded by a reflector region which is surrounded by a fast neutron absorber region, which in turn is surrounded by a slow neutron absorber region. Liquid sodium is used as the primary coolant and circulates through the core which contains the fuel elements. Control of the reactor is accomplished by varying the ability of the reflector region to reflect neutrons back into the core of the reactor. For this purpose the reflector is comprised of moderator and control elements having varying effects on reactivity, the control elements being arranged and actuated by groups to give regulation, shim, and safety control.

  17. NUCLEAR REACTOR

    DOEpatents

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  18. REACTOR SHIELD

    DOEpatents

    Wigner, E.P.; Ohlinger, L.E.; Young, G.J.; Weinberg, A.M.

    1959-02-17

    Radiation shield construction is described for a nuclear reactor. The shield is comprised of a plurality of steel plates arranged in parallel spaced relationship within a peripheral shell. Reactor coolant inlet tubes extend at right angles through the plates and baffles are arranged between the plates at right angles thereto and extend between the tubes to create a series of zigzag channels between the plates for the circulation of coolant fluid through the shield. The shield may be divided into two main sections; an inner section adjacent the reactor container and an outer section spaced therefrom. Coolant through the first section may be circulated at a faster rate than coolant circulated through the outer section since the area closest to the reactor container is at a higher temperature and is more radioactive. The two sections may have separate cooling systems to prevent the coolant in the outer section from mixing with the more contaminated coolant in the inner section.

  19. 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)

  20. NEUTRONIC REACTORS

    DOEpatents

    Vernon, H.C.

    1959-01-13

    A neutronic reactor of the heterogeneous, fluid cooled tvpe is described. The reactor is comprised of a pressure vessel containing the moderator and a plurality of vertically disposed channels extending in spaced relationship through the moderator. Fissionable fuel material is placed within the channels in spaced relationship thereto to permit circulation of the coolant fluid. Separate means are provided for cooling the moderator and for circulating a fluid coolant thru the channel elements to cool the fuel material.

  1. 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)

  2. NUCLEAR REACTOR

    DOEpatents

    Breden, C.R.; Dietrich, J.R.

    1961-06-20

    A water-soluble non-volatile poison may be introduced into a reactor to nullify excess reactivity. The poison is removed by passing a side stream of the water containing the soluble poison to an evaporation chamber. The vapor phase is returned to the reactor to decrease the concentration of soluble poison and the liquid phase is returned to increase the concentration of soluble poison.

  3. 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.

  4. Research reactors - an overview

    SciTech Connect

    West, C.D.

    1997-03-01

    A broad overview of different types of research and type reactors is provided in this paper. Reactor designs and operating conditions are briefly described for four reactors. The reactor types described include swimming pool reactors, the High Flux Isotope Reactor, the Mark I TRIGA reactor, and the Advanced Neutron Source reactor. Emphasis in the descriptions is placed on safety-related features of the reactors. 7 refs., 7 figs., 2 tabs.

  5. NEUTRONIC REACTOR

    DOEpatents

    Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

    1958-09-01

    This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

  6. POWER REACTOR

    DOEpatents

    Zinn, W.H.

    1958-07-01

    A fast nuclear reactor system ls described for producing power and radioactive isotopes. The reactor core is of the heterogeneous, fluid sealed type comprised of vertically arranged elongated tubular fuel elements having vertical coolant passages. The active portion is surrounded by a neutron reflector and a shield. The system includes pumps and heat exchangers for the primary and secondary coolant circuits. The core, primary coolant pump and primary heat exchanger are disposed within an irapenforate tank which is filled with the primary coolant, in this case a liquid metal such as Na or NaK, to completely submerge these elements. The tank is completely surrounded by a thick walled concrete shield. This reactor system utilizes enriched uranium or plutonium as the fissionable material, uranium or thorium as a diluent and thorium or uranium containing less than 0 7% of the U/sup 235/ isotope as a fertile material.

  7. NEUTRONIC REACTOR

    DOEpatents

    Metcalf, H.E.

    1957-10-01

    A reactor of the type which preferably uses plutonium as the fuel and a liquid moderator, preferably ordinary water, and which produces steam within the reactor core due to the heat of the chain reaction is described. In the reactor shown the fuel elements are essentially in the form of trays and are ventically stacked in spaced relationship. The water moderator is continuously supplied to the trays to maintain a constant level on the upper surfaces of the fuel element as it is continually evaporated by the heat. The steam passes out through the spaces between the fuel elements and is drawn off at the top of the core. The fuel elements are clad in aluminum to prevent deterioration thereof with consequent contamimation of the water.

  8. NUCLEAR REACTOR

    DOEpatents

    Christy, R.F.

    1958-07-15

    A nuclear reactor of the homogeneous liquid fuel type is described wherein the fissionable isotope is suspended or dissolved in a liquid moderator such as water. The reactor core is comprised essentially of a spherical vessel for containing the reactive composition surrounded by a reflector, preferably of beryllium oxide. The reactive composition may be an ordinary water solution of a soluble salt of uranium, the quantity of fissionable isotope in solution being sufficient to provide a critical mass in the vessel. The liquid fuel is stored in a tank of non-crtttcal geometry below the reactor vessel and outside of the reflector and is passed from the tank to the vessel through a pipe connecting the two by air pressure means. Neutron absorbing control and safety rods are operated within slots in the reflector adjacent to the vessel.

  9. Bioconversion reactor

    DOEpatents

    McCarty, Perry L.; Bachmann, Andre

    1992-01-01

    A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

  10. REACTOR CONTROL

    DOEpatents

    Fortescue, P.; Nicoll, D.

    1962-04-24

    A control system employed with a high pressure gas cooled reactor in which a control rod is positioned for upward and downward movement into the neutron field from a position beneath the reactor is described. The control rod is positioned by a coupled piston cylinder releasably coupled to a power drive means and the pressurized coolant is directed against the lower side of the piston. The coolant pressure is offset by a higher fiuid pressure applied to the upper surface of the piston and means are provided for releasing the higher pressure on the upper side of the piston so that the pressure of the coolant drives the piston upwardly, forcing the coupled control rod into the ncutron field of the reactor. (AEC)

  11. Catalytic reactor

    SciTech Connect

    Aaron, Timothy Mark; Shah, Minish Mahendra; Jibb, Richard John

    2009-03-10

    A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

  12. NEUTRONIC REACTORS

    DOEpatents

    Wigner, E.P.; Young, G.J.

    1958-10-14

    A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

  13. NUCLEAR REACTOR

    DOEpatents

    Young, G.

    1963-01-01

    This patent covers a power-producing nuclear reactor in which fuel rods of slightly enriched U are moderated by heavy water and cooled by liquid metal. The fuel rods arranged parallel to one another in a circle are contained in a large outer closed-end conduit that extends into a tank containing the heavy water. Liquid metal is introduced into the large conduit by a small inner conduit that extends within the circle of fuel rods to a point near the lower closed end of the outer conduit. (AEC) Production Reactors

  14. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Szilard, L.

    1957-09-24

    Reactors of the type employing plates of natural uranium in a moderator are discussed wherein the plates are um-formly disposed in parallel relationship to each other thereby separating the moderator material into distinct and individual layers. Each plate has an uninterrupted sunface area substantially equal to the cross-sectional area of the active portion of the reactor, the particular size of the plates and the volume ratio of moderator to uranium required to sustain a chain reaction being determinable from the known purity of these materials and other characteristics such as the predictable neutron losses due to the formation of radioactive elements of extremely high neutron capture cross section.

  15. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.; Weinberg, A.W.; Young, G.J.

    1958-04-15

    A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.

  16. Neutronic reactor

    DOEpatents

    Wende, Charles W. J.

    1976-08-17

    A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

  17. Neutronic reactor

    DOEpatents

    Carleton, John T.

    1977-01-25

    A graphite-moderated nuclear reactor includes channels between blocks of graphite and also includes spacer blocks between adjacent channeled blocks with an axis of extension normal to that of the axis of elongation of the channeled blocks to minimize changes in the physical properties of the graphite as a result of prolonged neutron bombardment.

  18. NEUTRONIC REACTOR

    DOEpatents

    Creutz, E.C.; Ohlinger, L.A.; Weinberg, A.M.; Wigner, E.P.; Young, G.J.

    1959-10-27

    BS>A reactor cooled by water, biphenyl, helium, or other fluid with provision made for replacing the fuel rods with the highest plutonium and fission product content without disassembling the entire core and for promptly cooling the rods after their replacement in order to prevent build-up of heat from fission product activity is described.

  19. Sonochemical Reactors.

    PubMed

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  20. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1962-12-25

    A reactor is described comprising a plurality of horizontal trays containing a solution of a fissionable material, the trays being sleeved on a vertical tube which contains a vertically-reciprocable control rod, a gas-tight chamber enclosing the trays, and means for conducting vaporized moderator from the chamber and for replacing vaporized moderator in the trays. (AEC)

  1. NEUTRONIC REACTORS

    DOEpatents

    Anderson, H.L.

    1958-10-01

    The design of control rods for nuclear reactors are described. In this design the control rod consists essentially of an elongated member constructed in part of a neutron absorbing material and having tube means extending therethrough for conducting a liquid to cool the rod when in use.

  2. Sonochemical Reactors.

    PubMed

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation. PMID:27573503

  3. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1960-09-27

    A unit assembly is described for a neutronic reactor comprising a tube and plurality of spaced parallel sandwiches in the tube extending lengthwise thereof, each sandwich including a middle plate having a central opening for plutonium and other openings for fertile material at opposite ends of the plate.

  4. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1959-12-15

    A reactor which is particularly adapted tu serve as a heat source for a nuclear powered alrcraft or rocket is described. The core of this reactor consists of a porous refractory modera;or body which is impregnated with fissionable nuclei. The core is designed so that its surface forms tapered inlet and outlet ducts which are separated by the porous moderator body. In operation a gaseous working fluid is circulated through the inlet ducts to the surface of the moderator, enters and passes through the porous body, and is heated therein. The hot gas emerges into the outlet ducts and is available to provide thrust. The principle advantage is that tremendous quantities of gas can be quickly heated without suffering an excessive pressure drop.

  5. NUCLEAR REACTOR

    DOEpatents

    Treshow, M.

    1958-08-19

    A neuclear reactor is described of the heterogeneous type and employing replaceable tubular fuel elements and heavy water as a coolant and moderator. A pluraltty of fuel tubesa having their axes parallel, extend through a tank type pressure vessel which contatns the liquid moderator. The fuel elements are disposed within the fuel tubes in the reaetive portion of the pressure vessel during normal operation and the fuel tubes have removable plug members at each end to permit charging and discharging of the fuel elements. The fuel elements are cylindrical strands of jacketed fissionable material having helical exterior ribs. A bundle of fuel elements are held within each fuel tube with their longitudinal axes parallel, the ribs serving to space them apart along their lengths. Coolant liquid is circulated through the fuel tubes between the spaced fuel elements. Suitable control rod and monitoring means are provided for controlling the reactor.

  6. REACTOR MONITORING

    DOEpatents

    Bugbee, S.J.; Hanson, V.F.; Babcock, D.F.

    1959-02-01

    A neutron density inonitoring means for reactors is described. According to this invention a tunnel is provided beneath and spaced from the active portion of the reactor and extends beyond the opposite faces of the activc portion. Neutron beam holes are provided between the active portion and the tunnel and open into the tunnel near the middle thereof. A carriage operates back and forth in the tunnel and is adapted to convey a neutron detector, such as an ion chamber, and position it beneath one of the neutron beam holes. This arrangement affords convenient access of neutron density measuring instruments to a location wherein direct measurement of neutron density within the piles can be made and at the same time affords ample protection to operating personnel.

  7. NEUTRONIC REACTOR

    DOEpatents

    Wade, E.J.

    1958-09-16

    This patent relates to a reflector means for a neutronic reactor. A reflector comprised of a plurality of vertically movable beryllium control members is provided surrounding the sides of the reactor core. An absorber of fast neutrons comprised of natural uramum surrounds the reflector. An absorber of slow neutrons surrounds the absorber of fast neutrons and is formed of a plurality of beryllium blocks having natural uranium members distributcd therethrough. in addition, a movable body is positioned directly below the core and is comprised of a beryllium reflector and an absorbing member attached to the botiom thereof, the absorbing member containing a substance selected from the goup consisting of natural urantum and Th/sup 232/.

  8. Nuclear reactor

    DOEpatents

    Wade, Elman E.

    1979-01-01

    A nuclear reactor including two rotatable plugs and a positive top core holddown structure. The top core holddown structure is divided into two parts: a small core cover, and a large core cover. The small core cover, and the upper internals associated therewith, are attached to the small rotating plug, and the large core cover, with its associated upper internals, is attached to the large rotating plug. By so splitting the core holddown structures, under-the-plug refueling is accomplished without the necessity of enlarging the reactor pressure vessel to provide a storage space for the core holddown structure during refueling. Additionally, the small and large rotating plugs, and their associated core covers, are arranged such that the separation of the two core covers to permit rotation is accomplished without the installation of complex lifting mechanisms.

  9. REACTOR UNLOADING

    DOEpatents

    Leverett, M.C.

    1958-02-18

    This patent is related to gas cooled reactors wherein the fuel elements are disposed in vertical channels extending through the reactor core, the cooling gas passing through the channels from the bottom to the top of the core. The invention is a means for unloading the fuel elements from the core and comprises dump values in the form of flat cars mounted on wheels at the bottom of the core structure which support vertical stacks of fuel elements. When the flat cars are moved, either manually or automatically, for normal unloading purposes, or due to a rapid rise in the reproduction ratio within the core, the fuel elements are permtted to fall by gravity out of the core structure thereby reducing the reproduction ratio or stopping the reaction as desired.

  10. Neutronic reactor

    DOEpatents

    Lewis, Warren R.

    1978-05-30

    A graphite-moderated, water-cooled nuclear reactor including a plurality of rectangular graphite blocks stacked in abutting relationship in layers, alternate layers having axes which are normal to one another, alternate rows of blocks in alternate layers being provided with a channel extending through the blocks, said channeled blocks being provided with concave sides and having smaller vertical dimensions than adjacent blocks in the same layer, there being nuclear fuel in the channels.

  11. NUCLEAR REACTORS

    DOEpatents

    Koch, L.J.; Rice, R.E. Jr.; Denst, A.A.; Rogers, A.J.; Novick, M.

    1961-12-01

    An active portion assembly for a fast neutron reactor is described wherein physical distortions resulting in adverse changes in the volume-to-mass ratio are minimized. A radially expandable locking device is disposed within a cylindrical tube within each fuel subassembly within the active portion assembly, and clamping devices expandable toward the center of the active portion assembly are disposed around the periphery thereof. (AEC)

  12. 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.

  13. NEUTRONIC REACTORS

    DOEpatents

    Anderson, J.B.

    1960-01-01

    A reactor is described which comprises a tank, a plurality of coaxial steel sleeves in the tank, a mass of water in the tank, and wire grids in abutting relationship within a plurality of elongated parallel channels within the steel sleeves, the wire being provided with a plurality of bends in the same plane forming adjacent parallel sections between bends, and the sections of adjacent grids being normally disposed relative to each other.

  14. NUCLEAR REACTOR

    DOEpatents

    Grebe, J.J.

    1961-01-24

    A core structure for neutronic reactors adapted for the propulsion of aircraft and rockets is offered. The core is designed for cooling by gaseous media, and comprises a plurality of hollow tapered tubular segments of a porous moderating material impregniated with fissionable fuel nested about a common axis. Alternate ends of the segments are joined. In operation a coolant gas passes through the porous structure and is heated.

  15. REACTOR CONTROL

    DOEpatents

    Ruano, W.J.

    1957-12-10

    This patent relates to nuclear reactors of the type which utilize elongited rod type fuel elements immersed in a liquid moderator and shows a design whereby control of the chain reaction is obtained by varying the amount of moderator or reflector material. A central tank for containing liquid moderator and fuel elements immersed therein is disposed within a surrounding outer tank providing an annular space between the two tanks. This annular space is filled with liquid moderator which functions as a reflector to reflect neutrons back into the central reactor tank to increase the reproduction ratio. Means are provided for circulating and cooling the moderator material in both tanks and additional means are provided for controlling separately the volume of moderator in each tank, which latter means may be operated automatically by a neutron density monitoring device. The patent also shows an arrangement for controlling the chain reaction by injecting and varying an amount of poisoning material in the moderator used in the reflector portion of the reactor.

  16. Nuclear Reactors. Revised.

    ERIC Educational Resources Information Center

    Hogerton, John F.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: How Reactors Work; Reactor Design; Research, Teaching, and Materials Testing; Reactors (Research, Teaching and Materials); Production Reactors; Reactors for Electric Power…

  17. Nuclear reactor

    DOEpatents

    Pennell, William E.; Rowan, William J.

    1977-01-01

    A nuclear reactor in which the core components, including fuel-rod assemblies, control-rod assemblies, fertile rod-assemblies, and removable shielding assemblies, are supported by a plurality of separate inlet modular units. These units are referred to as inlet module units to distinguish them from the modules of the upper internals of the reactor. The modular units are supported, each removable independently of the others, in liners in the supporting structure for the lower internals of the reactor. The core assemblies are removably supported in integral receptacles or sockets of the modular units. The liners, units, sockets and assmblies have inlet openings for entry of the fluid. The modular units are each removably mounted in the liners with fluid seals interposed between the opening in the liner and inlet module into which the fluid enters and the upper and lower portion of the liner. Each assembly is similarly mounted in a corresponding receptacle with fluid seals interposed between the openings where the fluid enters and the lower portion of the receptacle or fitting closely in these regions. As fluid flows along each core assembly a pressure drop is produced along the fluid so that the fluid which emerges from each core assembly is at a lower pressure than the fluid which enters the core assembly. However because of the seals interposed in the mountings of the units and assemblies the pressures above and below the units and assemblies are balanced and the units are held in the liners and the assemblies are held in the receptacles by their weights as they have a higher specific gravity than the fluid. The low-pressure spaces between each module and its liner and between each core assembly and its module is vented to the low-pressure regions of the vessel to assure that fluid which leaks through the seals does not accumulate and destroy the hydraulic balance.

  18. REACTOR COMPONETN

    DOEpatents

    Creutz, E.C.

    1959-10-27

    A reactor fuel element comprised of a slug of fissionable material disposed in a sheath of corrosion resistantmaterial is described. The sheath is in the form of a tubular container closed at one end and is in tight-fitting engagement with the peripheral sunface of the slug. An inner cap is insented into the open end of the sheath against the slug, which end is then bent around the inner cap and welded thereto. An outer cap is then welded around its peripheny to the bent portion of the container.

  19. 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.

  20. Hybrid adsorptive membrane reactor

    NASA Technical Reports Server (NTRS)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  1. Hybrid adsorptive membrane reactor

    DOEpatents

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  2. Control Means for Reactor

    DOEpatents

    Manley, J. H.

    1961-06-27

    An apparatus for controlling a nuclear reactor includes a tank just below the reactor, tubes extending from the tank into the reactor, and a thermally expansible liquid neutron absorbent material in the tank. The liquid in the tank is exposed to a beam of neutrons from the reactor which heats the liquid causing it to expand into the reactor when the neutron flux in the reactor rises above a predetermincd danger point. Boron triamine may be used for this purpose.

  3. NEUTRONIC REACTOR

    DOEpatents

    Stewart, H.B.

    1958-12-23

    A nuclear reactor of the type speclfically designed for the irradiation of materials is discussed. In this design a central cyllndrical core of moderating material ls surrounded by an active portlon comprlsed of an annular tank contalning fissionable material immersed ln a liquid moderator. The active portion ls ln turn surrounded by a reflector, and a well ls provided in the center of the core to accommodate the materlals to be irradiated. The over-all dimensions of the core ln at least one plane are equal to or greater than twice the effective slowing down length and equal to or less than twlce the effective diffuslon length for neutrons in the core materials.

  4. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1957-09-17

    A reactor of the type having coolant liquid circulated through clad fuel elements geometrically arranged in a solid moderator, such as graphite, is described. The core is enclosed in a pressure vessel and suitable shielding, wherein means is provided for circulating vapor through the core to superheat the same. This is accomplished by drawing off the liquid which has been heated in the core due to the fission of the fuel, passing it to a nozzle within a chamber where it flashes into a vapor, and then passing the vapor through separate tubes extending through the moderator to pick up more heat developed in the core due to the fission of the fuel, thereby producing superheated vapor.

  5. NEUTRONIC REACTOR

    DOEpatents

    Daniels, F.

    1962-12-18

    A power plant is described comprising a turbine and employing round cylindrical fuel rods formed of BeO and UO/sub 2/ and stacks of hexagonal moderator blocks of BeO provided with passages that loosely receive the fuel rods so that coolant may flow through the passages over the fuels to remove heat. The coolant may be helium or steam and fiows through at least one more heat exchanger for producing vapor from a body of fluid separate from the coolant, which fluid is to drive the turbine for generating electricity. By this arrangement the turbine and directly associated parts are free of particles and radiations emanating from the reactor. (AEC)

  6. Nuclear reactor

    DOEpatents

    Yant, Howard W.; Stinebiser, Karl W.; Anzur, Gregory C.

    1977-01-01

    A nuclear reactor, particularly a liquid-metal breeder reactor, whose upper internals include outlet modules for channeling the liquid-metal coolant from selected areas of the outlet of the core vertically to the outlet plenum. The modules are composed of a highly-refractory, high corrosion-resistant alloy, for example, INCONEL-718. Each module is disposed to confine and channel generally vertically the coolant emitted from a subplurality of core-component assemblies. Each module has a grid with openings, each opening disposed to receive the coolant from an assembly of the subplurality. The grid in addition serves as a holdown for the assemblies of the corresponding subplurality preventing their excessive ejection upwardly from the core. In the region directly over the core the outlet modules are of such peripheral form that they nest forming a continuum over the core-component assemblies whose outlet coolant they confine. Each subassembly includes a chimney which confines the coolant emitted by its corresponding subassemblies to generally vertical flow between the outlet of the core and the outlet plenum. Each subplurality of assemblies whose emitted coolant is confined by an outlet module includes assemblies which emit lower-temperature coolant, for example, a control-rod assembly, or fertile assemblies, and assemblies which emit coolant of substantially higher temperature, for example, fuel-rod assemblies. The coolants of different temperatures are mixed in the chimneys reducing the effect of stripping (hot-cold temperature fluctuations) on the remainder of the upper internals which are composed typically of AISI-304 or AISI-316 stainless steel.

  7. Reactor safety method

    DOEpatents

    Vachon, Lawrence J.

    1980-03-11

    This invention relates to safety means for preventing a gas cooled nuclear reactor from attaining criticality prior to start up in the event the reactor core is immersed in hydrogenous liquid. This is accomplished by coating the inside surface of the reactor coolant channels with a neutral absorbing material that will vaporize at the reactor's operating temperature.

  8. NEUTRONIC REACTOR MANIPULATING DEVICE

    DOEpatents

    Ohlinger, L.A.

    1962-08-01

    A cable connecting a control rod in a reactor with a motor outside the reactor for moving the rod, and a helical conduit in the reactor wall, through which the cable passes are described. The helical shape of the conduit prevents the escape of certain harmful radiations from the reactor. (AEC)

  9. Nuclear reactor

    DOEpatents

    Thomson, Wallace B.

    2004-03-16

    A nuclear reactor comprising a cylindrical pressure vessel, an elongated annular core centrally disposed within and spaced from the pressure vessel, and a plurality of ducts disposed longitudinally of the pressure vessel about the periphery thereof, said core comprising an annular active portion, an annular reflector just inside the active portion, and an annular reflector just outside the active a portion, said annular active portion comprising rectangular slab, porous fuel elements radially disposed around the inner reflector and extending the length of the active portion, wedge-shaped, porous moderator elements disposed adjacent one face of each fuel element and extending the length of the fuel element, the fuel and moderator elements being oriented so that the fuel elements face each other and the moderator elements do likewise, adjacent moderator elements being spaced to provide air inlet channels, and adjacent fuel elements being spaced to provide air outlet channels which communicate with the interior of the peripheral ducts, and means for introducing air into the air inlet channels which passes through the porous moderator elements and porous fuel elements to the outlet channel.

  10. Hybrid plasmachemical reactor

    SciTech Connect

    Lelevkin, V. M. Smirnova, Yu. G.; Tokarev, A. V.

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  11. Attrition reactor system

    SciTech Connect

    Scott, Charles D.; Davison, Brian H.

    1993-01-01

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

  12. Attrition reactor system

    SciTech Connect

    Scott, C.D.; Davison, B.H.

    1993-09-28

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur. 2 figures.

  13. Period meter for reactors

    DOEpatents

    Rusch, Gordon K.

    1976-01-06

    An improved log N amplifier type nuclear reactor period meter with reduced probability for noise-induced scrams is provided. With the reactor at low power levels a sampling circuit is provided to determine the reactor period by measuring the finite change in the amplitude of the log N amplifier output signal for a predetermined time period, while at high power levels, differentiation of the log N amplifier output signal provides an additional measure of the reactor period.

  14. NEUTRONIC REACTOR POWER PLANT

    DOEpatents

    Metcalf, H.E.

    1962-12-25

    This patent relates to a nuclear reactor power plant incorporating an air-cooled, beryllium oxide-moderated, pebble bed reactor. According to the invention means are provided for circulating a flow of air through tubes in the reactor to a turbine and for directing a sidestream of the circu1ating air through the pebble bed to remove fission products therefrom as well as assist in cooling the reactor. (AEC)

  15. Reactor System Transient Code.

    1999-07-14

    RELAP3B describes the behavior of water-cooled nuclear reactors during postulated accidents or power transients, such as large reactivity excursions, coolant losses or pump failures. The program calculates flows, mass and energy inventories, pressures, temperatures, and steam qualities along with variables associated with reactor power, reactor heat transfer, or control systems. Its versatility allows one to describe simple hydraulic systems as well as complex reactor systems.

  16. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-03-02

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  17. High solids fermentation reactor

    DOEpatents

    Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

    1993-01-01

    A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

  18. Efficient Silicon Reactor

    NASA Technical Reports Server (NTRS)

    Bates, H. E.; Hill, D. M.; Jewett, D. N.

    1983-01-01

    High-purity silicon efficiently produced and transferred by continuous two-cycle reactor. New reactor operates in relatively-narrow temperature rate and uses large surfaces area to minimize heat expenditure and processing time in producing silicon by hydrogen reduction of trichlorosilane. Two cycles of reactor consists of silicon production and removal.

  19. NUCLEAR REACTOR CONTROL SYSTEM

    DOEpatents

    Epler, E.P.; Hanauer, S.H.; Oakes, L.C.

    1959-11-01

    A control system is described for a nuclear reactor using enriched uranium fuel of the type of the swimming pool and other heterogeneous nuclear reactors. Circuits are included for automatically removing and inserting the control rods during the course of normal operation. Appropriate safety circuits close down the nuclear reactor in the event of emergency.

  20. Advanced Test Reactor Tour

    SciTech Connect

    Miley, Don

    2011-01-01

    The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  1. NEUTRONIC REACTOR SHIELDING

    DOEpatents

    Borst, L.B.

    1961-07-11

    A special hydrogenous concrete shielding for reactors is described. In addition to Portland cement and water, the concrete essentially comprises 30 to 60% by weight barytes aggregate for enhanced attenuation of fast neutrons. The biological shields of AEC's Oak Ridge Graphite Reactor and Materials Testing Reactor are particular embodiments.

  2. Improved vortex reactor system

    DOEpatents

    Diebold, James P.; Scahill, John W.

    1995-01-01

    An improved vortex reactor system for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor.

  3. Advanced Test Reactor Tour

    ScienceCinema

    Miley, Don

    2016-07-12

    The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  4. Neutron behavior, reactor control, and reactor heat transfer. Volume four

    SciTech Connect

    Not Available

    1986-01-01

    Volume four covers neutron behavior (neutron absorption, how big are nuclei, neutron slowing down, neutron losses, the self-sustaining reactor), reactor control (what is controlled in a reactor, controlling neutron population, is it easy to control a reactor, range of reactor control, what happens when the fuel burns up, controlling a PWR, controlling a BWR, inherent safety of reactors), and reactor heat transfer (heat generation in a nuclear reactor, how is heat removed from a reactor core, heat transfer rate, heat transfer properties of the reactor coolant).

  5. Nuclear reactor overflow line

    DOEpatents

    Severson, Wayne J.

    1976-01-01

    The overflow line for the reactor vessel of a liquid-metal-cooled nuclear reactor includes means for establishing and maintaining a continuous bleed flow of coolant amounting to 5 to 10% of the total coolant flow through the overflow line to prevent thermal shock to the overflow line when the reactor is restarted following a trip. Preferably a tube is disposed concentrically just inside the overflow line extending from a point just inside the reactor vessel to an overflow tank and a suction line is provided opening into the body of liquid metal in the reactor vessel and into the annulus between the overflow line and the inner tube.

  6. Reactor vessel support system

    DOEpatents

    Golden, Martin P.; Holley, John C.

    1982-01-01

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  7. Reactor water cleanup system

    DOEpatents

    Gluntz, D.M.; Taft, W.E.

    1994-12-20

    A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling. 1 figure.

  8. Reactor water cleanup system

    DOEpatents

    Gluntz, Douglas M.; Taft, William E.

    1994-01-01

    A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

  9. High temperature reactors

    NASA Astrophysics Data System (ADS)

    Dulera, I. V.; Sinha, R. K.

    2008-12-01

    With the advent of high temperature reactors, nuclear energy, in addition to producing electricity, has shown enormous potential for the production of alternate transport energy carrier such as hydrogen. High efficiency hydrogen production processes need process heat at temperatures around 1173-1223 K. Bhabha Atomic Research Centre (BARC), is currently developing concepts of high temperature reactors capable of supplying process heat around 1273 K. These reactors would provide energy to facilitate combined production of hydrogen, electricity, and drinking water. Compact high temperature reactor is being developed as a technology demonstrator for associated technologies. Design has been also initiated for a 600 MWth innovative high temperature reactor. High temperature reactor development programme has opened new avenues for research in areas like advanced nuclear fuels, high temperature and corrosion resistant materials and protective coatings, heavy liquid metal coolant technologies, etc. The paper highlights design of these reactors and their material related requirements.

  10. Spinning fluids reactor

    DOEpatents

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  11. Nuclear Reactor Physics

    NASA Astrophysics Data System (ADS)

    Stacey, Weston M.

    2001-02-01

    An authoritative textbook and up-to-date professional's guide to basic and advanced principles and practices Nuclear reactors now account for a significant portion of the electrical power generated worldwide. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. Nuclear reactor physics is the core discipline of nuclear engineering, and as the first comprehensive textbook and reference on basic and advanced nuclear reactor physics to appear in a quarter century, this book fills a large gap in the professional literature. Nuclear Reactor Physics is a textbook for students new to the subject, for others who need a basic understanding of how nuclear reactors work, as well as for those who are, or wish to become, specialists in nuclear reactor physics and reactor physics computations. It is also a valuable resource for engineers responsible for the operation of nuclear reactors. Dr. Weston Stacey begins with clear presentations of the basic physical principles, nuclear data, and computational methodology needed to understand both the static and dynamic behaviors of nuclear reactors. This is followed by in-depth discussions of advanced concepts, including extensive treatment of neutron transport computational methods. As an aid to comprehension and quick mastery of computational skills, he provides numerous examples illustrating step-by-step procedures for performing the calculations described and chapter-end problems. Nuclear Reactor Physics is a useful textbook and working reference. It is an excellent self-teaching guide for research scientists, engineers, and technicians involved in industrial, research, and military applications of nuclear reactors, as well as government regulators who wish to increase their understanding of nuclear reactors.

  12. HORIZONTAL BOILING REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1958-11-18

    Reactors of the boiling water type are described wherein water serves both as the moderator and coolant. The reactor system consists essentially of a horizontal pressure vessel divided into two compartments by a weir, a thermal neutronic reactor core having vertical coolant passages and designed to use water as a moderator-coolant posltioned in one compartment, means for removing live steam from the other compartment and means for conveying feed-water and water from the steam compartment to the reactor compartment. The system further includes auxiliary apparatus to utilize the steam for driving a turbine and returning the condensate to the feed-water inlet of the reactor. The entire system is designed so that the reactor is self-regulating and has self-limiting power and self-limiting pressure features.

  13. Modelling of biofilm reactors

    SciTech Connect

    Rodrigues, A.; Grasmick, A.; Elmaleh, S.

    1982-10-01

    Comprehensive models of biofilm reactors are developed. Model I assumes a zero-order reaction of a limiting substrate and a diffusional mass transport through the biofilm; in the diffusion-controlled regime the model is fully characterized by one parameter alpha. From this model the conversion of substrate or reactor efficiency can be calculated, for continuously stirred tank reactors (CSTRs) and plug flow reactors respectively, as follows: EA = )alpha(alpha + 2)) 1/2 - alpha; and Ep = (2 alpha) 1/2 - alpha/2: Validation of the model is tested for different experimental systems. Model II includes liquid film mass transfer resistance. The conversion gap between plug flow reactors and CSTRs is always lower than 25% and, as a first approximation, the biofilm reactor design does not then require accurate residence time distribution measurements. (Refs. 23).

  14. Hybrid reactors. [Fuel cycle

    SciTech Connect

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  15. Thermionic space reactors overview

    SciTech Connect

    Wetch, J.R.; Britt, E.J.; Fitzpatrick, G.O.; Rasor, N.S.

    1983-08-01

    The multi-national development of thermionic reactor systems is summarized in the context of the past general space nuclear reactor program and the recent renewed interest in space nuclear power. Comparison of various alternate reactor space power systems indicates that only the in-core thermionic reactor approach has the performance and growth potential required to provide the power levels potentially needed for shuttle-launchable systems by the year 2000 at reactor coolant and system temperatures that are near the current state-of-the-art. It is concluded that all shuttle- launchable high power space reactor systems require high-temperature, long-endurance nuclear fuels, and that high priority characterization and development of such fuels is essential to successfully realize power systems that can enable the space missions presently being considered.

  16. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Dreffin, R.S.

    1959-12-15

    A control means for a nuclear reactor is described. Particularly a device extending into the active portion of the reactor consisting of two hollow elements coaxially disposed and forming a channel therebetween, the cross sectional area of the channel increasing from each extremity of the device towards the center thereof. An element of neutron absorbing material is slidably positionable within the inner hollow element and a fluid reactor poison is introduced into the channel defined by the two hollow elements.

  17. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Goett, J.J.

    1961-01-24

    A system is described which includes a neutronic reactor containing a dispersion of fissionable material in a liquid moderator as fuel and a conveyor to which a portion of the dispersion may be passed and wherein the self heat of the slurry evaporates the moderator. Means are provided for condensing the liquid moderator and returning it to the reactor and for conveying the dried fissionable material away from the reactor.

  18. Improved vortex reactor system

    DOEpatents

    Diebold, J.P.; Scahill, J.W.

    1995-05-09

    An improved vortex reactor system is described for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor. 12 figs.

  19. THERMAL NEUTRONIC REACTOR

    DOEpatents

    Spinrad, B.I.

    1960-01-12

    A novel thermal reactor was designed in which a first reflector formed from a high atomic weight, nonmoderating material is disposed immediately adjacent to the reactor core. A second reflector composed of a moderating material is disposed outwardly of the first reflector. The advantage of this novel reflector arrangement is that the first reflector provides a high slow neutron flux in the second reflector, where irradiation experiments may be conducted with a small effect on reactor reactivity.

  20. FLOW SYSTEM FOR REACTOR

    DOEpatents

    Zinn, W.H.

    1963-06-11

    A reactor is designed with means for terminating the reaction when returning coolant is below a predetermined temperature. Coolant flowing from the reactor passes through a heat exchanger to a lower reservoir, and then circulates between the lower reservoir and an upper reservoir before being returned to the reactor. Means responsive to the temperature of the coolant in the return conduit terminate the chain reaction when the temperature reaches a predetermined minimum value. (AEC)

  1. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, J.

    1996-03-19

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

  2. Pressurized fluidized bed reactor

    DOEpatents

    Isaksson, Juhani

    1996-01-01

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

  3. HOMOGENEOUS NUCLEAR POWER REACTOR

    DOEpatents

    King, L.D.P.

    1959-09-01

    A homogeneous nuclear power reactor utilizing forced circulation of the liquid fuel is described. The reactor does not require fuel handling outside of the reactor vessel during any normal operation including complete shutdown to room temperature, the reactor being selfregulating under extreme operating conditions and controlled by the thermal expansion of the liquid fuel. The liquid fuel utilized is a uranium, phosphoric acid, and water solution which requires no gus exhaust system or independent gas recombining system, thereby eliminating the handling of radioiytic gas.

  4. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Treshow, M.

    1959-02-10

    A reactor system incorporating a reactor of the heterogeneous boiling water type is described. The reactor is comprised essentially of a core submerged adwater in the lower half of a pressure vessel and two distribution rings connected to a source of water are disposed within the pressure vessel above the reactor core, the lower distribution ring being submerged adjacent to the uppcr end of the reactor core and the other distribution ring being located adjacent to the top of the pressure vessel. A feed-water control valve, responsive to the steam demand of the load, is provided in the feedwater line to the distribution rings and regulates the amount of feed water flowing to each distribution ring, the proportion of water flowing to the submerged distribution ring being proportional to the steam demand of the load. This invention provides an automatic means exterior to the reactor to control the reactivity of the reactor over relatively long periods of time without relying upon movement of control rods or of other moving parts within the reactor structure.

  5. Polymerization Reactor Engineering.

    ERIC Educational Resources Information Center

    Skaates, J. Michael

    1987-01-01

    Describes a polymerization reactor engineering course offered at Michigan Technological University which focuses on the design and operation of industrial polymerization reactors to achieve a desired degree of polymerization and molecular weight distribution. Provides a list of the course topics and assigned readings. (TW)

  6. The Integral Fast Reactor

    SciTech Connect

    Till, C.E.; Chang, Y.I. ); Lineberry, M.J. )

    1990-01-01

    Argonne National Laboratory, since 1984, has been developing the Integral Fast Reactor (IFR). This paper will describe the way in which this new reactor concept came about; the technical, public acceptance, and environmental issues that are addressed by the IFR; the technical progress that has been made; and our expectations for this program in the near term. 5 refs., 3 figs.

  7. Light water reactor program

    SciTech Connect

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  8. Operating US power reactors

    SciTech Connect

    Silver, E.G.

    1982-07-01

    The operation of US power reactors during March and April 1982 is summarized. Events of special note are discussed in the text, and the operational performance of all licensed power reactors is presented. These data are taken from the monthly Operating Units Status Report prepared by the Nuclear Regulatory Commission (NRC).

  9. Compact torsatron reactors

    SciTech Connect

    Lyon, J.F.; Carreras, B.A.; Lynch, V.E.; Tolliver, J.S.; Sviatoslavsky, I.N.

    1988-05-01

    Low-aspect-ratio torsatron configurations could lead to compact stellarator reactors with R/sub 0/ = 8--11m, roughly one-half to one-third the size of more conventional stellarator reactor designs. Minimum-size torsatron reactors are found using various assumptions. Their size is relatively insensitive to the choice of the conductor parameters and depends mostly on geometrical constraints. The smallest size is obtained by eliminating the tritium breeding blanket under the helical winding on the inboard side and by reducing the radial depth of the superconducting coil. Engineering design issues and reactor performance are examined for three examples to illustrate the feasibility of this approach for compact reactors and for a medium-size (R/sub 0/ approx. = 4 m,/bar a/ /approx lt/ 1 m) copper-coil ignition experiment. 26 refs., 11 figs., 7 tabs.

  10. REACTOR FUEL SCAVENGING MEANS

    DOEpatents

    Coffinberry, A.S.

    1962-04-10

    A process for removing fission products from reactor liquid fuel without interfering with the reactor's normal operation or causing a significant change in its fuel composition is described. The process consists of mixing a liquid scavenger alloy composed of about 44 at.% plutoniunm, 33 at.% lanthanum, and 23 at.% nickel or cobalt with a plutonium alloy reactor fuel containing about 3 at.% lanthanum; removing a portion of the fuel and scavenger alloy from the reactor core and replacing it with an equal amount of the fresh scavenger alloy; transferring the portion to a quiescent zone where the scavenger and the plutonium fuel form two distinct liquid layers with the fission products being dissolved in the lanthanum-rich scavenger layer; and the clean plutonium-rich fuel layer being returned to the reactor core. (AEC)

  11. Status of French reactors

    SciTech Connect

    Ballagny, A.

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  12. Reactor neutrino monitoring

    NASA Astrophysics Data System (ADS)

    Lhuillier, D.

    2009-03-01

    Nuclear reactors are the most intense man-controlled sources of antineutrinos and as such have hosted number of key physics experiments, from the antineutrino discovery to modern oscillation measurements. At the present time, both detection technology and understanding of fundamental physics are mature enough to think about antineutrinos as a new tool for reactor monitoring. We describe below how antineutrinos can provide online information on reactor operation and amount of plutonium accumulated in the core. Reactors are the only sources of plutonium on earth and this element can be chemically separated from the rest of the nuclear fuel and diverted into nuclear weapons. We present in the next sections the unique features antineutrino detectors could provide to safeguards agencies such as IAEA. We review the worldwide efforts to develop small ( 1m scale) antineutrino detectors dedicated to automated and non-intrusive reactor monitoring.

  13. Nuclear reactor control column

    DOEpatents

    Bachovchin, Dennis M.

    1982-01-01

    The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

  14. Slurry reactor design studies

    SciTech Connect

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. ); Akgerman, A. ); Smith, J.M. )

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  15. Reactor Safety Research Programs

    SciTech Connect

    Edler, S. K.

    1981-07-01

    This document summarizes the work performed by Pacific Northwest Laboratory (PNL) from January 1 through March 31, 1981, for the Division of Reactor Safety Research within the U.S. Nuclear Regulatory Commission (NRC). Evaluations of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibility of determining the strength of structural graphite, evaluating the feasibility of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the integrity of pressurized water reactor (PWR) steam generator tubes where service-induced degradation has been indicated. Experimental data and analytical models are being provided to aid in decision-making regarding pipeto- pipe impacts following postulated breaks in high-energy fluid system piping. Core thermal models are being developed to provide better digital codes to compute the behavior of full-scale reactor systems under postulated accident conditions. Fuel assemblies and analytical support are being provided for experimental programs at other facilities. These programs include loss-ofcoolant accident (LOCA) simulation tests at the NRU reactor, Chalk River, Canada; fuel rod deformation, severe fuel damage, and postaccident coolability tests for the ESSOR reactor Super Sara Test Program, Ispra, Italy; the instrumented fuel assembly irradiation program at Halden, Norway; and experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory (INEL). These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  16. Nuclear reactor reflector

    DOEpatents

    Hopkins, Ronald J.; Land, John T.; Misvel, Michael C.

    1994-01-01

    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

  17. Nuclear reactor reflector

    DOEpatents

    Hopkins, R.J.; Land, J.T.; Misvel, M.C.

    1994-06-07

    A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled. 12 figs.

  18. Microfluidic electrochemical reactors

    DOEpatents

    Nuzzo, Ralph G.; Mitrovski, Svetlana M.

    2011-03-22

    A microfluidic electrochemical reactor includes an electrode and one or more microfluidic channels on the electrode, where the microfluidic channels are covered with a membrane containing a gas permeable polymer. The distance between the electrode and the membrane is less than 500 micrometers. The microfluidic electrochemical reactor can provide for increased reaction rates in electrochemical reactions using a gaseous reactant, as compared to conventional electrochemical cells. Microfluidic electrochemical reactors can be incorporated into devices for applications such as fuel cells, electrochemical analysis, microfluidic actuation, pH gradient formation.

  19. CONTROL FOR NEUTRONIC REACTOR

    DOEpatents

    Lichtenberger, H.V.; Cameron, R.A.

    1959-03-31

    S>A control rod operating device in a nuclear reactor of the type in which the control rod is gradually withdrawn from the reactor to a position desired during stable operation is described. The apparatus is comprised essentially of a stop member movable in the direction of withdrawal of the control rod, a follower on the control rod engageable with the stop and means urging the follower against the stop in the direction of withdrawal. A means responsive to disengagement of the follower from the stop is provided for actuating the control rod to return to the reactor shut-down position.

  20. REACTOR CONTROL SYSTEM

    DOEpatents

    MacNeill, J.H.; Estabrook, J.Y.

    1960-05-10

    A reactor control system including a continuous tape passing through a first coolant passageway, over idler rollers, back through another parallel passageway, and over motor-driven rollers is described. Discrete portions of fuel or poison are carried on two opposed active sections of the tape. Driving the tape in forward or reverse directions causes both active sections to be simultaneously inserted or withdrawn uniformly, tending to maintain a more uniform flux within the reactor. The system is particularly useful in mobile reactors, where reduced inertial resistance to control rod movement is important.

  1. COOLED NEUTRONIC REACTOR

    DOEpatents

    Binner, C.R.; Wilkie, C.B.

    1958-03-18

    This patent relates to a design for a reactor of the type in which a fluid coolant is flowed through the active portion of the reactor. This design provides for the cooling of the shielding material as well as the reactor core by the same fluid coolant. The core structure is a solid moderator having coolant channels in which are disposed the fuel elements in rod or slug form. The coolant fluid enters the chamber in the shield, in which the core is located, passes over the inner surface of said chamber, enters the core structure at the center, passes through the coolant channels over the fuel elements and out through exhaust ducts.

  2. NUCLEAR REACTOR FUEL SYSTEMS

    DOEpatents

    Thamer, B.J.; Bidwell, R.M.; Hammond, R.P.

    1959-09-15

    Homogeneous reactor fuel solutions are reported which provide automatic recombination of radiolytic gases and exhibit large thermal expansion characteristics, thereby providing stability at high temperatures and enabling reactor operation without the necessity of apparatus to recombine gases formed by the radiolytic dissociation of water in the fuel and without the necessity of liquid fuel handling outside the reactor vessel except for recovery processes. The fuels consist of phosphoric acid and water solutions of enriched uranium, wherein the uranium is in either the hexavalent or tetravalent state.

  3. Spherical torus fusion reactor

    DOEpatents

    Martin Peng, Y.K.M.

    1985-10-03

    The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

  4. Fast Breeder Reactor studies

    SciTech Connect

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  5. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Metcalf, H.E.

    1958-10-14

    Methods of controlling reactors are presented. Specifically, a plurality of neutron absorber members are adjustably disposed in the reactor core at different distances from the center thereof. The absorber members extend into the core from opposite faces thereof and are operated by motive means coupled in a manner to simultaneously withdraw at least one of the absorber members while inserting one of the other absorber members. This feature effects fine control of the neutron reproduction ratio by varying the total volume of the reactor effective in developing the neutronic reaction.

  6. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  7. NEUTRONIC REACTOR STRUCTURE

    DOEpatents

    Daniels, F.

    1961-10-24

    A reactor core, comprised of vertical stacks of hexagonal blocks of beryllium oxide having axial cylindrical apertures extending therethrough and cylindrical rods of a sintered mixture of uranium dioxide and beryllium oxide, is described. (AEC)

  8. NEUTRONIC REACTOR FUEL COMPOSITION

    DOEpatents

    Thurber, W.C.

    1961-01-10

    Uranium-aluminum alloys in which boron is homogeneously dispersed by adding it as a nickel boride are described. These compositions have particular utility as fuels for neutronic reactors, boron being present as a burnable poison.

  9. Molten metal reactors

    DOEpatents

    Bingham, Dennis N; Klingler, Kerry M; Turner, Terry D; Wilding, Bruce M

    2013-11-05

    A molten metal reactor for converting a carbon material and steam into a gas comprising hydrogen, carbon monoxide, and carbon dioxide is disclosed. The reactor includes an interior crucible having a portion contained within an exterior crucible. The interior crucible includes an inlet and an outlet; the outlet leads to the exterior crucible and may comprise a diffuser. The exterior crucible may contain a molten alkaline metal compound. Contained between the exterior crucible and the interior crucible is at least one baffle.

  10. Compact power reactor

    DOEpatents

    Wetch, Joseph R.; Dieckamp, Herman M.; Wilson, Lewis A.

    1978-01-01

    There is disclosed a small compact nuclear reactor operating in the epithermal neutron energy range for supplying power at remote locations, as for a satellite. The core contains fuel moderator elements of Zr hydride with 7 w/o of 93% enriched uranium alloy. The core has a radial beryllium reflector and is cooled by liquid metal coolant such as NaK. The reactor is controlled and shut down by moving portions of the reflector.

  11. Future reactor experiments

    SciTech Connect

    Wen, Liangjian

    2015-07-15

    The non-zero neutrino mixing angle θ{sub 13} has been discovered and precisely measured by the current generation short-baseline reactor neutrino experiments. It opens the gate of measuring the leptonic CP-violating phase and enables the neutrino mass ordering. The JUNO and RENO-50 proposals aim at resolving the neutrino mass ordering using reactors. The experiment design, physics sensitivity, technical challenges as well as the progresses of those two proposed experiments are reviewed in this paper.

  12. Reactor Safety Research Programs

    SciTech Connect

    Dotson, CW

    1980-08-01

    This document summarizes the work performed by Pacific Northwest laboratory from October 1 through December 31, 1979, for the Division of Reactor Safety Research within the Nuclear Regulatory Commission. Evaluation of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibilty of determining structural graphite strength, evaluating the feasibilty of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the remaining integrity of pressurized water reactor steam generator tubes where service-induced degradation has been indicated. Test assemblies and analytical support are being provided for experimental programs at other facilities. These programs include the loss-of-coolant accident simulation tests at the NRU reactor, Chalk River, Canada; the fuel rod deformation and post-accident coolability tests for the ESSOR Test Reactor Program, lspra, Italy; the blowdown and reflood tests in the test facility at Cadarache, France; the instrumented fuel assembly irradiation program at Halden, Norway; and the experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory. These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

  13. F Reactor Inspection

    SciTech Connect

    Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

    2014-10-29

    Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

  14. F Reactor Inspection

    ScienceCinema

    Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

    2016-07-12

    Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

  15. Moon base reactor system

    NASA Technical Reports Server (NTRS)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  16. NEUTRONIC REACTOR CONSTRUCTION AND OPERATION

    DOEpatents

    West, J.M.; Weills, J.T.

    1960-03-15

    A method is given for operating a nuclear reactor having a negative coefficient of reactivity to compensate for the change in reactor reactivity due to the burn-up of the xenon peak following start-up of the reactor. When it is desired to start up the reactor within less than 72 hours after shutdown, the temperature of the reactor is lowered prior to start-up, and then gradually raised after start-up.

  17. REACTOR GROUT THERMAL PROPERTIES

    SciTech Connect

    Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

    2011-01-28

    Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

  18. Reactor Safety Planning for Prometheus Project, for Naval Reactors Information

    SciTech Connect

    P. Delmolino

    2005-05-06

    The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

  19. EBT reactor analysis

    SciTech Connect

    Uckan, N. A.; Jaeger, E. F.; Santoro, R. T.; Spong, D. A.; Uckan, T.; Owen, L. W.; Barnes, J. M.; McBride, J. B.

    1983-08-01

    This report summarizes the results of a recent ELMO Bumpy Torus (EBT) reactor study that includes ring and core plasma properties with consistent treatment of coupled ring-core stability criteria and power balance requirements. The principal finding is that constraints imposed by these coupling and other physics and technology considerations permit a broad operating window for reactor design optimization. Within this operating window, physics and engineering systems analysis and cost sensitivity studies indicate that reactors with <..beta../sub core/> approx. 6 to 10%, P approx. 1200 to 1700 MW(e), wall loading approx. 1.0 to 2.5 MW/m/sup 2/, and recirculating power fraction (including ring-sustaining power and all other reactors auxiliaries) approx. 10 to 15% are possible. A number of concept improvements are also proposed that are found to offer the potential for further improvement of the reactor size and parameters. These include, but are not limited to, the use of: (1) supplementary coils or noncircular mirror coils to improve magnetic geometry and reduce size, (2) energetic ion rings to improve ring power requirements, (3) positive potential to enhance confinement and reduce size, and (4) profile control to improve stability and overall fusion power density.

  20. REACTOR AND NOVEL METHOD

    DOEpatents

    Young, G.J.; Ohlinger, L.A.

    1958-06-24

    A nuclear reactor of the type which uses a liquid fuel and a method of controlling such a reactor are described. The reactor is comprised essentially of a tank for containing the liquid fuel such as a slurry of discrete particles of fissionnble material suspended in a heavy water moderator, and a control means in the form of a disc of neutron absorbirg material disposed below the top surface of the slurry and parallel thereto. The diameter of the disc is slightly smaller than the diameter of the tank and the disc is perforated to permit a flow of the slurry therethrough. The function of the disc is to divide the body of slurry into two separate portions, the lower portion being of a critical size to sustain a nuclear chain reaction and the upper portion between the top surface of the slurry and the top surface of the disc being of a non-critical size. The method of operation is to raise the disc in the reactor until the lower portion of the slurry has reached a critical size when it is desired to initiate the reaction, and to lower the disc in the reactor to reduce the size of the lower active portion the slurry to below criticality when it is desired to stop the reaction.

  1. Methanation assembly using multiple reactors

    DOEpatents

    Jahnke, Fred C.; Parab, Sanjay C.

    2007-07-24

    A methanation assembly for use with a water supply and a gas supply containing gas to be methanated in which a reactor assembly has a plurality of methanation reactors each for methanating gas input to the assembly and a gas delivery and cooling assembly adapted to deliver gas from the gas supply to each of said methanation reactors and to combine water from the water supply with the output of each methanation reactor being conveyed to a next methanation reactor and carry the mixture to such next methanation reactor.

  2. Nuclear reactor safety device

    DOEpatents

    Hutter, Ernest

    1986-01-01

    A safety device is disclosed for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of an upward thermal excursion. Such safety device comprises a laminated helical ribbon configured as a tube-like helical coil having contiguous helical turns with slidably abutting edges. The helical coil is disclosed as a portion of a drive member connected axially to the control rod. The laminated ribbon is formed of outer and inner laminae. The material of the outer lamina has a greater thermal coefficient of expansion than the material of the inner lamina. In the event of an upward thermal excursion, the laminated helical coil curls inwardly to a smaller diameter. Such inward curling causes the total length of the helical coil to increase by a substantial increment, so that the control rod is axially repositioned by a corresponding amount to reduce the power output of the reactor.

  3. Reactor for exothermic reactions

    DOEpatents

    Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

    1993-03-02

    A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  4. A NEUTRONIC REACTOR

    DOEpatents

    Luebke, E.A.; Vandenberg, L.B.

    1959-09-01

    A nuclear reactor for producing thermoelectric power is described. The reactor core comprises a series of thermoelectric assemblies, each assembly including fissionable fuel as an active element to form a hot junction and a thermocouple. The assemblies are disposed parallel to each other to form spaces and means are included for Introducing an electrically conductive coolant between the assemblies to form cold junctions of the thermocouples. An electromotive force is developed across the entire series of the thermoelectric assemblies due to fission heat generated in the fuel causing a current to flow perpendicular to the flow of coolant and is distributed to a load outside of the reactor by means of bus bars electrically connected to the outermost thermoelectric assembly.

  5. Dynamic bed reactor

    SciTech Connect

    Stormo, K.E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix. 27 figs.

  6. Reactor for exothermic reactions

    DOEpatents

    Smith, Jr., Lawrence A.; Hearn, Dennis; Jones, Jr., Edward M.

    1993-01-01

    A liquid phase process for oligomerization of C.sub.4 and C.sub.5 isoolefins or the etherification thereof with C.sub.1 to C.sub.6 alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120.degree. to 300.degree. F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

  7. Dynamic bed reactor

    DOEpatents

    Stormo, Keith E.

    1996-07-02

    A dynamic bed reactor is disclosed in which a compressible open cell foam matrix is periodically compressed and expanded to move a liquid or fluid through the matrix. In preferred embodiments, the matrix contains an active material such as an enzyme, biological cell, chelating agent, oligonucleotide, adsorbent or other material that acts upon the liquid or fluid passing through the matrix. The active material may be physically immobilized in the matrix, or attached by covalent or ionic bonds. Microbeads, substantially all of which have diameters less than 50 microns, can be used to immobilize the active material in the matrix and further improve reactor efficiency. A particularly preferred matrix is made of open cell polyurethane foam, which adsorbs pollutants such as polychlorophenol or o-nitrophenol. The reactors of the present invention allow unidirectional non-laminar flow through the matrix, and promote intimate exposure of liquid reactants to active agents such as microorganisms immobilized in the matrix.

  8. Heat dissipating nuclear reactor

    DOEpatents

    Hunsbedt, Anstein; Lazarus, Jonathan D.

    1987-01-01

    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extends from the metal base plate downwardly and outwardly into the earth.

  9. Heat dissipating nuclear reactor

    DOEpatents

    Hunsbedt, A.; Lazarus, J.D.

    1985-11-21

    Disclosed is a nuclear reactor containment adapted to retain and cool core debris in the unlikely event of a core meltdown and subsequent breach in the reactor vessel. The reactor vessel is seated in a cavity which has a thick metal sidewall that is integral with a thick metal basemat at the bottom of the cavity. The basemat extends beyond the perimeter of the cavity sidewall. Underneath the basemat is a porous bed with water pipes and steam pipes running into it. Water is introduced into the bed and converted into steam which is vented to the atmosphere. A plurality of metal pilings in the form of H-beams extend from the metal base plate downwardly and outwardly into the earth.

  10. Thermionic Reactor Design Studies

    SciTech Connect

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  11. Compact reactor design automation

    NASA Technical Reports Server (NTRS)

    Nassersharif, Bahram; Gaeta, Michael J.

    1991-01-01

    A conceptual compact reactor design automation experiment was performed using the real-time expert system G2. The purpose of this experiment was to investigate the utility of an expert system in design; in particular, reactor design. The experiment consisted of the automation and integration of two design phases: reactor neutronic design and fuel pin design. The utility of this approach is shown using simple examples of formulating rules to ensure design parameter consistency between the two design phases. The ability of G2 to communicate with external programs even across networks provides the system with the capability of supplementing the knowledge processing features with conventional canned programs with possible applications for realistic iterative design tools.

  12. REACTOR CONTROL DEVICE

    DOEpatents

    Graham, R.H.

    1962-09-01

    A wholly mechanical compact control device is designed for automatically rendering the core of a fission reactor subcritical in response to core temperatures in excess of the design operating temperature limit. The control device comprises an expansible bellows interposed between the base of a channel in a reactor core and the inner end of a fuel cylinder therein which is normally resiliently urged inwardly. The bellows contains a working fluid which undergoes a liquid to vapor phase change at a temperature substantially equal to the design temperature limit. Hence, the bellows abruptiy expands at this limiting temperature to force the fuel cylinder outward and render the core subcritical. The control device is particularly applicable to aircraft propulsion reactor service. (AEC)

  13. Merchant Marine Ship Reactor

    DOEpatents

    Sankovich, M. F.; Mumm, J. F.; North, Jr, D. C.; Rock, H. R.; Gestson, D. K.

    1961-05-01

    A nuclear reactor for use in a merchant marine ship is described. The reactor is of pressurized, light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements that are confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass. (AEC)

  14. MERCHANT MARINE SHIP REACTOR

    DOEpatents

    Mumm, J.F.; North, D.C. Jr.; Rock, H.R.; Geston, D.K.

    1961-05-01

    A nuclear reactor is described for use in a merchant marine ship. The reactor is of pressurized light water cooled and moderated design in which three passes of the water through the core in successive regions of low, intermediate, and high heat generation and downflow in a fuel region are made. The foregoing design makes a compact reactor construction with extended core life. The core has an egg-crate lattice containing the fuel elements confined between a lower flow baffle and upper grid plate, with the latter serving also as part of a turn- around manifold from which the entire coolant is distributed into the outer fuel elements for the second pass through the core. The inner fuel elements are cooled in the third pass.

  15. Advanced light water reactor requirements document: Chapter 4, Reactor systems

    SciTech Connect

    Not Available

    1987-06-01

    The purpose of this chapter of the Advanced Light Water Reactor (ALWR) Plant Requirements Document is to establish utility requirements for the design of the Reactor Systems of Advanced LWR plants consistent with the objectives and principles of the ALWR program. The scope of this chapter covers the following for Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR): reactor pressure vessel, nozzles and safe-ends, reactor internals, in-vessel portions of fluid systems (including reactor internal pumps (Emergency Core Cooling System (ECCS) piping and spargers), nuclear fuel, and the control rods and control rod drive system (including hydraulic supply and accumulators). Special tools required for reactor system maintenance, inspection and testing are also covered.

  16. Looking Southwest at Reactor Box Furnaces With Reactor Boxes and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking Southwest at Reactor Box Furnaces With Reactor Boxes and Repossessed Uranium in Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

  17. Plug Flow Reactor Simulator

    SciTech Connect

    Larson, Richard S.

    1996-07-30

    PLUG is a computer program that solves the coupled steady state continuity, momentum, energy, and species balance equations for a plug flow reactor. Both homogeneous (gas-phase) and heterogenous (surface) reactions can be accommodated. The reactor may be either isothermal or adiabatic or may have a specified axial temperature or heat flux profile; alternatively, an ambient temperature and an overall heat-transfer coefficient can be specified. The crosssectional area and surface area may vary with axial position, and viscous drag is included. Ideal gas behavior and surface site conservation are assumed.

  18. NEUTRONIC REACTOR CONTROL ELEMENT

    DOEpatents

    Newson, H.W.

    1960-09-13

    A novel composite neutronic reactor control element is offered. The element comprises a multiplicity of sections arranged in end-to-end relationship, each of the sections having a markedly different neutron-reactive characteristic. For example, a three-section control element could contain absorber, moderator, and fuel sections. By moving such an element longitudinally through a reactor core, reactivity is decreased by the absorber, increased slightly by the moderator, or increased substantially by the fuel. Thus, control over a wide reactivity range is provided.

  19. MEANS FOR SHIELDING REACTORS

    DOEpatents

    Garrison, W.M.; McClinton, L.T.; Burton, M.

    1959-03-10

    A reactor of the heterageneous, heavy water moderated type is described. The reactor is comprised of a plurality of vertically disposed fuel element tubes extending through a tank of heavy water moderator and adapted to accommodate a flow of coolant water in contact with the fuel elements. A tank containing outgoing coolant water is disposed above the core to function is a radiation shield. Unsaturated liquid hydrocarbon is floated on top of the water in the shield tank to reduce to a minimum the possibility of the occurrence of explosive gaseous mixtures resulting from the neutron bombardment of the water in the shield tank.

  20. Perspectives on reactor safety

    SciTech Connect

    Haskin, F.E.; Camp, A.L.

    1994-03-01

    The US Nuclear Regulatory Commission (NRC) maintains a technical training center at Chattanooga, Tennessee to provide appropriate training to both new and experienced NRC employees. This document describes a one-week course in reactor, safety concepts. The course consists of five modules: (1) historical perspective; (2) accident sequences; (3) accident progression in the reactor vessel; (4) containment characteristics and design bases; and (5) source terms and offsite consequences. The course text is accompanied by slides and videos during the actual presentation of the course.

  1. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L.

    1988-01-01

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

  2. NEUTRONIC REACTOR SYSTEM

    DOEpatents

    Daniels, F.

    1957-10-15

    Gas-cooled solid-moderator type reactors wherein the fissionable fuel and moderator materials are each in the form of solid pebbles, or discrete particles, and are substantially homogeneously mixed in the proper proportion and placed within the core of the reactor are described. The shape of these discrete particles must be such that voids are present between them when mixed together. Helium enters the bottom of the core and passes through the voids between the fuel and moderator particles to absorb the heat generated by the chain reaction. The hot helium gas is drawn off the top of the core and may be passed through a heat exchanger to produce steam.

  3. ARIES tokamak reactor study

    SciTech Connect

    Steiner, D.; Embrechts, M.

    1990-07-01

    This is a status report on technical progress relative to the tasks identified for the fifth year of Grant No. FG02-85-ER52118. The ARIES tokamak reactor study is a multi-institutional effort to develop several visions of the tokamak as an attractive fusion reactor with enhanced economic, safety, and environmental features. The ARIES study is being coordinated by UCLA and involves a number of institutions, including RPI. The RPI group has been pursuing the following areas of research in the context of the ARIES-I design effort: MHD equilibrium and stability analyses; plasma-edge modeling and blanket materials issues. Progress in these areas is summarized herein.

  4. Plug Flow Reactor Simulator

    1996-07-30

    PLUG is a computer program that solves the coupled steady state continuity, momentum, energy, and species balance equations for a plug flow reactor. Both homogeneous (gas-phase) and heterogenous (surface) reactions can be accommodated. The reactor may be either isothermal or adiabatic or may have a specified axial temperature or heat flux profile; alternatively, an ambient temperature and an overall heat-transfer coefficient can be specified. The crosssectional area and surface area may vary with axial position,more » and viscous drag is included. Ideal gas behavior and surface site conservation are assumed.« less

  5. Particle bed reactor modeling

    NASA Technical Reports Server (NTRS)

    Sapyta, Joe; Reid, Hank; Walton, Lew

    1993-01-01

    The topics are presented in viewgraph form and include the following: particle bed reactor (PBR) core cross section; PBR bleed cycle; fuel and moderator flow paths; PBR modeling requirements; characteristics of PBR and nuclear thermal propulsion (NTP) modeling; challenges for PBR and NTP modeling; thermal hydraulic computer codes; capabilities for PBR/reactor application; thermal/hydralic codes; limitations; physical correlations; comparison of predicted friction factor and experimental data; frit pressure drop testing; cold frit mask factor; decay heat flow rate; startup transient simulation; and philosophy of systems modeling.

  6. Nuclear reactor apparatus

    DOEpatents

    Wade, Elman E.

    1978-01-01

    A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

  7. Fast quench reactor method

    SciTech Connect

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.; Berry, Ray A.

    1999-01-01

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream.

  8. Fast quench reactor method

    DOEpatents

    Detering, B.A.; Donaldson, A.D.; Fincke, J.R.; Kong, P.C.; Berry, R.A.

    1999-08-10

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a means of rapidly expanding a reactant stream, such as a restrictive convergent-divergent nozzle at its outlet end. Metal halide reactants are injected into the reactor chamber. Reducing gas is added at different stages in the process to form a desired end product and prevent back reactions. The resulting heated gaseous stream is then rapidly cooled by expansion of the gaseous stream. 8 figs.

  9. THERMAL NUCLEAR REACTOR

    DOEpatents

    Fenning, F.W.; Jackson, R.F.

    1957-09-24

    Nuclear reactors of the graphite moderated air cooled type in which canned slugs or rods of fissile material are employed are discussed. Such a reactor may be provided with a means for detecting dust particles in the exhausted air. The means employed are lengths of dust absorbent cord suspended in vertical holes in the shielding structure above each vertical coolant flow channel to hang in the path of the cooling air issuing from the channels, and associated spindles and drive motors for hauling the cords past detectors, such as Geiger counters, for inspecting the cords periodically. This design also enables detecting the individual channel in which a fault condition may have occurred.

  10. Diagnostics for hybrid reactors

    SciTech Connect

    Orsitto, Francesco Paolo

    2012-06-19

    The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

  11. Reactor operation environmental information document

    SciTech Connect

    Haselow, J.S.; Price, V.; Stephenson, D.E.; Bledsoe, H.W.; Looney, B.B.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimal impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.

  12. Inertial confinement fusion reactor systems

    SciTech Connect

    Frank, T.G.; Bohachevsky, I.O.; Pendergrass, J.H.

    1980-01-01

    A variety of reactor cavity concepts, drivers, and energy conversion mechanisms are being considered to realize commercial applications of ICF. Presented in this paper are: (1) a review of reactor concepts with estimates of practically achievable pulse repetition rates; (2) a survey of drivers with estimates of the requirements on reactor conditions imposed by beam propagation characteristics; and (3) an assessment of compatible driver-reactor combinations.

  13. Reactor operation safety information document

    SciTech Connect

    Not Available

    1990-01-01

    The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

  14. NRC Targets University Reactors.

    ERIC Educational Resources Information Center

    Marshall, Eliot

    1984-01-01

    The Nuclear Regulatory Commission (NRC) wants universities to convert to low-grade fuel in their research reactions. Researchers claim the conversion, which will bring U.S. reactors in line with a policy the NRC is trying to impress on foreigners, could be financially and scientifically costly. Impact of the policy is considered. (JN)

  15. Neutronic reactor thermal shield

    DOEpatents

    Wende, Charles W. J.

    1976-06-15

    1. The method of operating a water-cooled neutronic reactor having a graphite moderator which comprises flowing a gaseous mixture of carbon dioxide and helium, in which the helium comprises 40-60 volume percent of the mixture, in contact with the graphite moderator.

  16. Nuclear Reactors and Technology

    SciTech Connect

    Cason, D.L.; Hicks, S.C.

    1992-01-01

    This publication Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on the Energy Science and Technology Database and Nuclear Science Abstracts (NSA) database. Current information, added daily to the Energy Science and Technology Database, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user`s needs.

  17. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Picklesimer, M.L.; Thurber, W.C.

    1961-01-01

    A chemically nonreactive fuel composition for incorporation in aluminum- clad, plate type fuel elements for neutronic reactors is described. The composition comprises a mixture of aluminum and uranium carbide particles, the uranium carbide particles containing at least 80 wt.% UC/sub 2/.

  18. NEUTRONIC REACTOR SHIELD

    DOEpatents

    Fermi, E.; Zinn, W.H.

    1957-09-24

    The reactor radiation shield material is comprised of alternate layers of iron-containing material and compressed cellulosic material, such as masonite. The shielding material may be prefabricated in the form of blocks, which can be stacked together in ary desired fashion to form an effective shield.

  19. NEUTRONIC REACTOR FUEL PUMP

    DOEpatents

    Cobb, W.G.

    1959-06-01

    A reactor fuel pump is described which offers long life, low susceptibility to radiation damage, and gaseous fission product removal. An inert-gas lubricated bearing supports a journal on one end of the drive shsft. The other end has an impeller and expansion chamber which effect pumping and gas- liquid separation. (T.R.H.)

  20. Thermal Reactor Safety

    SciTech Connect

    Not Available

    1980-06-01

    Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

  1. University Reactor Instrumentation Program

    SciTech Connect

    Vernetson, W.G.

    1992-11-01

    Recognizing that the University Reactor Instrumentation Program was developed in response to widespread needs in the academic community for modernization and improvement of research and training reactors at institutions such as the University of Florida, the items proposed to be supported by this grant over its two year period have been selected as those most likely to reduce foreed outages, to meet regulatory concerns that had been expressed in recent years by Nuclear Regulatory Commission inspectors or to correct other facility problems and limitations. Department of Energy Grant Number DE-FG07-90ER129969 was provided to the University of Florida Training Reactor(UFTR) facility through the US Department of Energy's University Reactor Instrumentation Program. The original proposal submitted in February, 1990 requested support for UFTR facility instrumentation and equipment upgrades for seven items in the amount of $107,530 with $13,800 of this amount to be the subject of cost sharing by the University of Florida and $93,730 requested as support from the Department of Energy. A breakdown of the items requested and total cost for the proposed UFTR facility instrumentation and equipment improvements is presented.

  2. NETL - Chemical Looping Reactor

    ScienceCinema

    None

    2016-07-12

    NETL's Chemical Looping Reactor unit is a high-temperature integrated CLC process with extensive instrumentation to improve computational simulations. A non-reacting test unit is also used to study solids flow at ambient temperature. The CLR unit circulates approximately 1,000 pounds per hour at temperatures around 1,800 degrees Fahrenheit.

  3. SYSTEM FOR UNLOADING REACTORS

    DOEpatents

    Rand, A.C. Jr.

    1961-05-01

    An unloading device for individual vertical fuel channels in a nuclear reactor is shown. The channels are arranged in parallel rows and underneath each is a separate supporting block on which the fuel in the channel rests. The blocks are raounted in contiguous rows on an array of parallel pairs of tracks over the bottom of the reactor. Oblong hollows in the blocks form a continuous passageway through the middle of the row of blocks on each pair of tracks. At the end of each passageway is a horizontal grappling rod with a T- or L extension at the end next to the reactor of a length to permit it to pass through the oblong passageway in one position, but when rotated ninety degrees the head will strike one of the longer sides of the oblong hollow of one of the blocks. The grappling rod is actuated by a controllable reciprocating and rotating device which extends it beyond any individual block desired, rotates it and retracts it far enough to permit the fuel in the vertical channel above the block to fall into a handling tank below the reactor.

  4. Fossil fuel furnace reactor

    DOEpatents

    Parkinson, William J.

    1987-01-01

    A fossil fuel furnace reactor is provided for simulating a continuous processing plant with a batch reactor. An internal reaction vessel contains a batch of shale oil, with the vessel having a relatively thin wall thickness for a heat transfer rate effective to simulate a process temperature history in the selected continuous processing plant. A heater jacket is disposed about the reactor vessel and defines a number of independent controllable temperature zones axially spaced along the reaction vessel. Each temperature zone can be energized to simulate a time-temperature history of process material through the continuous plant. A pressure vessel contains both the heater jacket and the reaction vessel at an operating pressure functionally selected to simulate the continuous processing plant. The process yield from the oil shale may be used as feedback information to software simulating operation of the continuous plant to provide operating parameters, i.e., temperature profiles, ambient atmosphere, operating pressure, material feed rates, etc., for simulation in the batch reactor.

  5. NEUTRONIC REACTOR CONTROL

    DOEpatents

    Untermyer, S.; Hutter, E.

    1959-08-01

    This patent relates to "shadow" control of a nuclear reactor. The control means comprises a plurality ot elongated rods disposed adjacent and parallel to each other, The morphology and effects of gases generated within sections of neutron absorbing materials and equal length sections of neutron permeable materials together with means for longitudinally pcsitioning the rcds relative to each other.

  6. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Stacy, J.T.

    1958-12-01

    A reactor fuel element having a core of molybdenum-uranium alloy jacketed in stainless steel is described. A barrier layer of tungsten, tantalum, molybdenum, columbium, or silver is interposed between the core and jacket to prevent formation of a low melting eutectic between uranium and the varlous alloy constituents of the stainless steel.

  7. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1963-06-11

    A fuel plate is designed for incorporation into control rods of the type utilized in high-flux test reactors. The fuel plate is designed so that the portion nearest the poison section of the control rod contains about one-half as much fissionable material as in the rest of the plate, thereby eliminating dangerous flux peaking in that portion. (AEC)

  8. JACKETED REACTOR FUEL ELEMENT

    DOEpatents

    Smith, K.F.; Van Thyne, R.J.

    1958-12-01

    A fuel element is described for fast reactors comprised of a core of uranium metal containing material and a jacket around the core, the jacket consisting of from 2.5 to 15 percent of titanium, from 1 to 5 percent of niobium, and from 80 to 96.5 percent of vanadium.

  9. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Horning, W.A.; Lanning, D.D.; Donahue, D.J.

    1959-10-01

    A fuel slug for a reactor which acts as a safety device is described. The fuel slug is an aluminum tube with a foil lining the inside surface of the tube, the foil being fabricated of uranium in a lead matrix.

  10. NETL - Chemical Looping Reactor

    SciTech Connect

    2013-07-24

    NETL's Chemical Looping Reactor unit is a high-temperature integrated CLC process with extensive instrumentation to improve computational simulations. A non-reacting test unit is also used to study solids flow at ambient temperature. The CLR unit circulates approximately 1,000 pounds per hour at temperatures around 1,800 degrees Fahrenheit.

  11. WATER BOILER REACTOR

    DOEpatents

    King, L.D.P.

    1960-11-22

    As its name implies, this reactor utilizes an aqueous solution of a fissionable element salt, and is also conventional in that it contains a heat exchanger cooling coil immersed in the fuel. Its novelty lies in the utilization of a cylindrical reactor vessel to provide a critical region having a large and constant interface with a supernatant vapor region, and the use of a hollow sleeve coolant member suspended from the cover assembly in coaxial relation with the reactor vessel. Cool water is circulated inside this hollow coolant member, and a gap between its outer wall and the reactor vessel is used to carry off radiolytic gases for recombination in an external catalyst chamber. The central passage of the coolant member defines a reflux condenser passage into which the externally recombined gases are returned and condensed. The large and constant interface between fuel solution and vapor region prevents the formation of large bubbles and minimizes the amount of fuel salt carried off by water vapor, thus making possible higher flux densities, specific powers and power densities.

  12. Reactor component automatic grapple

    SciTech Connect

    Greenaway, P.R.

    1982-12-07

    A grapple for handling nuclear reactor components in a medium such as liquid sodium which, upon proper seating and alignment of the grapple with the component as sensed by a mechanical logic integral to the grapple, automatically seizes the component. The mechanical logic system also precludes seizure in the absence of proper seating and alignment.

  13. Reactor component automatic grapple

    DOEpatents

    Greenaway, Paul R.

    1982-01-01

    A grapple for handling nuclear reactor components in a medium such as liquid sodium which, upon proper seating and alignment of the grapple with the component as sensed by a mechanical logic integral to the grapple, automatically seizes the component. The mechanical logic system also precludes seizure in the absence of proper seating and alignment.

  14. Neutronic Reactor Structure

    DOEpatents

    Vernon, H. C.; Weinberg, A. M.

    1961-05-30

    The neutronic reactor is comprised of a core consisting of natural uranium and heavy water with a K-factor greater than unity. The core is surrounded by a reflector consisting of natural uranium and ordinary water with a Kfactor less than unity. (AEC)

  15. NEUTRONIC REACTOR STRUCTURE

    DOEpatents

    Weinberg, A.M.; Vernon, H.C.

    1961-05-30

    A neutronic reactor is described. It has a core consisting of natural uranium and heavy water and having a K-factor greater than unity which is surrounded by a reflector consisting of natural uranium and ordinary water having a Kfactor less than unity.

  16. Cermet fuel reactors

    SciTech Connect

    Cowan, C.L.; Palmer, R.S.; Van Hoomissen, J.E.; Bhattacharyya, S.K.; Barner, J.O.

    1987-09-01

    Cermet fueled nuclear reactors are attractive candidates for high performance space power systems. The cermet fuel consists of tungsten-urania hexagonal fuel blocks characterized by high strength at elevated temperatures, a high thermal conductivity and resultant high thermal shock resistance. Key features of the cermet fueled reactor design are (1) the ability to achieve very high coolant exit temperatures, and (2) thermal shock resistance during rapid power changes, and (3) two barriers to fission product release - the cermet matrix and the fuel element cladding. Additionally, thre is a potential for achieving a long operating life because of (1) the neutronic insensitivity of the fast-spectrum core to the buildup of fission products and (2) the utilization of a high strength refractory metal matrix and structural materials. These materials also provide resistance against compression forces that potentially might compact and/or reconfigure the core. In addition, the neutronic properties of the refractory materials assure that the reactor remains substantially subcritical under conditions of water immersion. It is concluded that cermet fueled reactors can be utilized to meet the power requirements for a broad range of advanced space applications. 4 refs., 4 figs., 3 tabs.

  17. NUCLEAR REACTOR COOLANT

    DOEpatents

    Colichman, E.L.

    1959-10-20

    The formation of new reactor coolants which suppress polymerization resulting from pyrolytic and radiation decomposition is described. The coolants consist of polyphenyls and condensed ring compounds having from two to about four carbon rings and from 0.1 to about 5% of beryllium or magnesium dispersed in the hydrocarbon.

  18. NUCLEAR REACTOR COOLANT

    DOEpatents

    Colichman, E.L.

    1959-10-20

    The formation of new reactor coolants which suppress polymerization resulting from pyrolitic and radiation decomposition is described. The coolants consist of polyphenyls and condensed ring compounds having from two to about four carbon rings and from 0.1 to about 10% of an alkall metal dispersed in the hydrocarbon.

  19. Nuclear reactor building

    DOEpatents

    Gou, Perng-Fei; Townsend, Harold E.; Barbanti, Giancarlo

    1994-01-01

    A reactor building for enclosing a nuclear reactor includes a containment vessel having a wetwell disposed therein. The wetwell includes inner and outer walls, a floor, and a roof defining a wetwell pool and a suppression chamber disposed thereabove. The wetwell and containment vessel define a drywell surrounding the reactor. A plurality of vents are disposed in the wetwell pool in flow communication with the drywell for channeling into the wetwell pool steam released in the drywell from the reactor during a LOCA for example, for condensing the steam. A shell is disposed inside the wetwell and extends into the wetwell pool to define a dry gap devoid of wetwell water and disposed in flow communication with the suppression chamber. In a preferred embodiment, the wetwell roof is in the form of a slab disposed on spaced apart support beams which define therebetween an auxiliary chamber. The dry gap, and additionally the auxiliary chamber, provide increased volume to the suppression chamber for improving pressure margin.

  20. Nuclear reactor building

    DOEpatents

    Gou, P.F.; Townsend, H.E.; Barbanti, G.

    1994-04-05

    A reactor building for enclosing a nuclear reactor includes a containment vessel having a wetwell disposed therein. The wetwell includes inner and outer walls, a floor, and a roof defining a wetwell pool and a suppression chamber disposed there above. The wetwell and containment vessel define a drywell surrounding the reactor. A plurality of vents are disposed in the wetwell pool in flow communication with the drywell for channeling into the wetwell pool steam released in the drywell from the reactor during a LOCA for example, for condensing the steam. A shell is disposed inside the wetwell and extends into the wetwell pool to define a dry gap devoid of wetwell water and disposed in flow communication with the suppression chamber. In a preferred embodiment, the wetwell roof is in the form of a slab disposed on spaced apart support beams which define there between an auxiliary chamber. The dry gap, and additionally the auxiliary chamber, provide increased volume to the suppression chamber for improving pressure margin. 4 figures.

  1. The First Reactor.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    On December 2, 1942, in a racquet court underneath the West Stands of Stagg Field at the University of Chicago, a team of scientists led by Enrico Fermi created the first controlled, self-sustaining nuclear chain reaction. This updated and revised story of the first reactor (or "pile") is based on postwar interviews (as told to Corbin Allardice…

  2. Fusion reactor materials

    SciTech Connect

    none,

    1989-01-01

    This paper discuses the following topics on fusion reactor materials: irradiation, facilities, test matrices, and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; fundamental mechanical behavior; radiation effects; development of structural alloys; solid breeding materials; and ceramics.

  3. REACTOR UNLOADING MEANS

    DOEpatents

    Cooper, C.M.

    1957-08-20

    A means for remotely unloading irradiated fuel slugs from a neutronic reactor core and conveying them to a remote storage tank is reported. The means shown is specifically adapted for use with a reactor core wherein the fuel slugs are slidably held in end to end abutting relationship in the horizontal coolant flow tubes, the slugs being spaced from tae internal walls of the tubes to permit continuous circulation of coolant water therethrough. A remotely operated plunger at the charging ends of the tubes is used to push the slugs through the tubes and out the discharge ends into a special slug valve which transfers the slug to a conveying tube leading into a storage tank. Water under pressure is forced through the conveying tube to circulate around the slug to cool it and also to force the slug through the conveving tube into the storage tank. The slug valve and conveying tube are shielded to prevent amy harmful effects caused by the radioactive slug in its travel from the reactor to the storage tank. With the disclosed apparatus, all the slugs in the reactor core can be conveyed to the storage tank shortly after shutdown by remotely located operating personnel.

  4. Minéralogie de la Lune étudiée par Spectro-imagerie visible et proche infrarouge. Apport des Données NIR de la Sonde Clementine

    NASA Astrophysics Data System (ADS)

    Le Mouélic, Stéphane

    2000-09-01

    Cette thèse est consacrée à l'analyse des données multi-spectrales de la caméra infrarouge NIR de la sonde Clementine. La lune est le seul corps planétaire pour lequel on dispose à la fois d'une vérité terrain (échantillons lunaires) et de données de télédétection globales non perturbées par une atmosphère. C'est donc le cas le plus favorable pour tester et valider des méthodes d'analyse de données de télédétection, ces méthodes pouvant ensuite être extrapolées à d'autres corps du système solaire. Les données NIR, bien que dans le domaine public depuis 1995, n'avaient jamais été exploitées auparavant du fait de problèmes majeurs d'étalonnage. La première partie de ce travail a consisté à s'affranchir des problèmes d'étalonnage, donnant ainsi accès à des observations inédites couvrant la totalité de la surface lunaire. Ces observations ont ensuite été mises à profit pour aborder les problèmes plus scientifiques de l'identification des minéraux et de l'extrapolation de la connaissance de quelques sites à l'ensemble du satellite. Des zones riches en olivine, minéral associé au manteau lunaire et rarement détecté en surface, ont été mises en évidence dans les régions des cratères Aristarchus et Copernicus. L'analyse systématique des propriétés spectrales et chimiques d'échantillons lunaires représentatifs, couplée aux données NIR, a ensuite permis de mettre en place une méthode de cartographie quantitative de la teneur en fer des sols observés, clarifiant ainsi le lien entre information spectrale et chimique. Cette méthode permet de discriminer entre les effets de composition et les effets d'altération de la surface suite aux impacts de micrométéorites et de particules du vent solaire. L'expérience acquise dans le cas lunaire est directement transposable à l'étude d'autres surfaces rocheuses sans atmosphère (cas de Mercure et des astéroïdes), et représente un premier pas vers le cas plus

  5. EMERGENCY SHUTDOWN FOR NUCLEAR REACTORS

    DOEpatents

    Paget, J.A.; Koutz, S.L.; Stone, R.S.; Stewart, H.B.

    1963-12-24

    An emergency shutdown or scram apparatus for use in a nuclear reactor that includes a neutron absorber suspended from a temperature responsive substance that is selected to fail at a preselected temperature in excess of the normal reactor operating temperature, whereby the neutron absorber is released and allowed to fall under gravity to a preselected position within the reactor core is presented. (AEC)

  6. REACTOR FUEL ELEMENTS TESTING CONTAINER

    DOEpatents

    Whitham, G.K.; Smith, R.R.

    1963-01-15

    This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

  7. The Solar Collector on Clementine Street.

    ERIC Educational Resources Information Center

    Stranix, Edward; Fleishman, Michael

    1980-01-01

    Listed are 12 energy activities, experiments, and projects which some eighth-grade students performed in their classroom and local community before they helped install a solar heating system on the roof of an old house during school time and on Saturdays. The building conversion project is described. (KC)

  8. Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors

    NASA Technical Reports Server (NTRS)

    Roth, R. J.

    1976-01-01

    The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

  9. Reactor operations Brookhaven medical research reactor, Brookhaven high flux beam reactor informal monthly report

    SciTech Connect

    Hauptman, H.M.; Petro, J.N.; Jacobi, O.

    1995-04-01

    This document is the April 1995 summary report on reactor operations at the Brookhaven Medical Research Reactor and the Brookhaven High Flux Beam Reactor. Ongoing experiments/irradiations in each are listed, and other significant operations functions are also noted. The HFBR surveillance testing schedule is also listed.

  10. Perspectives on research reactor utilization

    NASA Astrophysics Data System (ADS)

    Dodd, Brian; Dolan, Thomas J.; Laraia, Michele; Ritchie, Iain

    2002-01-01

    The current state of research reactors around the world is summarized using information from the Research Reactor Database. Some current trends of research reactors in advanced and developing countries are described. The need for strategic planning is emphasized, and elements of a typical strategic plan are presented. The problems of reactor lifetime extension, nuclear fuel cycle issues, and decommissioning are briefly discussed. It is concluded that research reactors will continue to be vital elements of the nuclear infrastructures in many countries, and that the IAEA can help countries solve their problems of utilization, safety, lifetime extension, fuel cycle, and decommissioning.

  11. Reactor vessel support system. [LMFBR

    DOEpatents

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  12. Reactor monitoring using antineutrino detectors

    NASA Astrophysics Data System (ADS)

    Bowden, N. S.

    2011-08-01

    Nuclear reactors have served as the antineutrino source for many fundamental physics experiments. The techniques developed by these experiments make it possible to use these weakly interacting particles for a practical purpose. The large flux of antineutrinos that leaves a reactor carries information about two quantities of interest for safeguards: the reactor power and fissile inventory. Measurements made with antineutrino detectors could therefore offer an alternative means for verifying the power history and fissile inventory of a reactor as part of International Atomic Energy Agency (IAEA) and/or other reactor safeguards regimes. Several efforts to develop this monitoring technique are underway worldwide.

  13. Nuclear Reactor Kinetics and Control.

    SciTech Connect

    JEFFERY,; LEWINS, D.

    2009-07-27

    Version 00 Dr. J.D. Lewins has now released the following legacy book for free distribution: Nuclear Reactor Kinetics and Control, Pergamon Press, London, 275 pages, 1978. 1. Introductory Review 2. Neutron and Precursor Equations 3. Elementary Solutions of the Kinetics Equations at Low Power 4. Linear Reactor Process Dynamics with Feedback 5. Power Reactor Control Systems 6. Fluctuations and Reactor Noise 7. Safety and Reliability 8. Non Linear Systems; Stability and Control 9. Analogue Computing Addendum: Jay Basken and Jeffery D. Lewins: Power Series Solution of the Reactor Kinetics Equations, Nuclear Science and Engineering: 122, 407-436 (1996) (authorized for distribution with the book: courtesy of the American Nuclear Society)

  14. N Reactor operational safety summary

    SciTech Connect

    Franz, G.R.; Quapp, W.J.; Ogden, D.M.

    1988-08-01

    This report is a safety summary of the N Reactor. Beginning with its conceptual design in the mid-1950`s, and throughout its 23 years of operation, continuous efforts have been made to ensure safe N Reactor operation and protection of the public health and safety. The N Reactor Updated Safety Analysis Report, completed in 1978(UNC1978), and its subsequent amendments document the safety bases of N Reactor. Following the April 1986 Chernobyl accident in the Soviet Union, a major effort to confirm N Reactor safety and further increase its safety margin was initiated. This effort, called the Safety Enhancement Program, reassessed the N Reactor using the latest accepted analysis techniques and commercial light-water reactor guidelines, where applicable. 122 refs., 38 figs., 10 tabs.

  15. Nuclear reactor construction with bottom supported reactor vessel

    DOEpatents

    Sharbaugh, John E.

    1987-01-01

    An improved liquid metal nuclear reactor construction has a reactor core and a generally cylindrical reactor vessel for holding a large pool of low pressure liquid metal coolant and housing the core within the pool. The reactor vessel has an open top end, a closed flat bottom end wall and a continuous cylindrical closed side wall interconnecting the top end and bottom end wall. The reactor also has a generally cylindrical concrete containment structure surrounding the reactor vessel and being formed by a cylindrical side wall spaced outwardly from the reactor vessel side wall and a flat base mat spaced below the reactor vessel bottom end wall. A central support pedestal is anchored to the containment structure base mat and extends upwardly therefrom to the reactor vessel and upwardly therefrom to the reactor core so as to support the bottom end wall of the reactor vessel and the lower end of the reactor core in spaced apart relationship above the containment structure base mat. Also, an annular reinforced support structure is disposed in the reactor vessel on the bottom end wall thereof and extends about the lower end of the core so as to support the periphery thereof. In addition, an annular support ring having a plurality of inward radially extending linear members is disposed between the containment structure base mat and the bottom end of the reactor vessel wall and is connected to and supports the reactor vessel at its bottom end on the containment structure base mat so as to allow the reactor vessel to expand radially but substantially prevent any lateral motions that might be imposed by the occurrence of a seismic event. The reactor construction also includes a bed of insulating material in sand-like granular form, preferably being high density magnesium oxide particles, disposed between the containment structure base mat and the bottom end wall of the reactor vessel and uniformly supporting the reactor vessel at its bottom end wall on the containment

  16. Nuclear reactor safety device

    DOEpatents

    Hutter, E.

    1983-08-15

    A safety device is described for use in a nuclear reactor for axially repositioning a control rod with respect to the reactor core in the event of a thermal excursion. It comprises a laminated strip helically configured to form a tube, said tube being in operative relation to said control rod. The laminated strip is formed of at least two materials having different thermal coefficients of expansion, and is helically configured such that the material forming the outer lamina of the tube has a greater thermal coefficient of expansion than the material forming the inner lamina of said tube. In the event of a thermal excursion the laminated strip will tend to curl inwardly so that said tube will increase in length, whereby as said tube increases in length it exerts a force on said control rod to axially reposition said control rod with respect to said core.

  17. Spherical torus fusion reactor

    DOEpatents

    Peng, Yueng-Kay M.

    1989-04-04

    A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

  18. Spherical torus fusion reactor

    DOEpatents

    Peng, Yueng-Kay M.

    1989-01-01

    A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.

  19. Fusion reactor pumped laser

    DOEpatents

    Jassby, D.L.

    1987-09-04

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam. 10 figs.

  20. ENGINEERING TEST REACTOR

    DOEpatents

    De Boisblanc, D.R.; Thomas, M.E.; Jones, R.M.; Hanson, G.H.

    1958-10-21

    Heterogeneous reactors of the type which is both cooled and moderated by the same fluid, preferably water, and employs highly enriched fuel are reported. In this design, an inner pressure vessel is located within a main outer pressure vessel. The reactor core and its surrounding reflector are disposed in the inner pressure vessel which in turn is surrounded by a thermal shield, Coolant fluid enters the main pressure vessel, fiows downward into the inner vessel where it passes through the core containing tbe fissionable fuel assemblies and control rods, through the reflector, thence out through the bottom of the inner vessel and up past the thermal shield to the discharge port in the main vessel. The fuel assemblles are arranged in the core in the form of a cross having an opening extending therethrough to serve as a high fast flux test facility.

  1. HOMOGENEOUS NUCLEAR REACTOR

    DOEpatents

    Hammond, R.P.; Busey, H.M.

    1959-02-17

    Nuclear reactors of the homogeneous liquid fuel type are discussed. The reactor is comprised of an elongated closed vessel, vertically oriented, having a critical region at the bottom, a lower chimney structure extending from the critical region vertically upwardly and surrounded by heat exchanger coils, to a baffle region above which is located an upper chimney structure containing a catalyst functioning to recombine radiolyticallydissociated moderator gages. In operation the liquid fuel circulates solely by convection from the critical region upwardly through the lower chimney and then downwardly through the heat exchanger to return to the critical region. The gases formed by radiolytic- dissociation of the moderator are carried upwardly with the circulating liquid fuel and past the baffle into the region of the upper chimney where they are recombined by the catalyst and condensed, thence returning through the heat exchanger to the critical region.

  2. AIR COOLED NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Szilard, L.

    1958-05-27

    A nuclear reactor of the air-cooled, graphite moderated type is described. The active core consists of a cubicle mass of graphite, approximately 25 feet in each dimension, having horizontal channels of square cross section extending between two of the opposite faces, a plurality of cylindrical uranium slugs disposed in end to end abutting relationship within said channels providing a space in the channels through which air may be circulated, and a cadmium control rod extending within a channel provided in the moderator. Suitable shielding is provlded around the core, as are also provided a fuel element loading and discharge means, and a means to circulate air through the coolant channels through the fuel charels to cool the reactor.

  3. COMPOSITE NEUTRONIC REACTOR

    DOEpatents

    Menke, J.R.

    1963-06-11

    This patent relates to a reactor having a core which comprises an inner active region and an outer active region, each region separately having a k effective less than one and a k infinity greater than one. The inner and outer regions in combination have a k effective at least equal to one and each region contributes substantially to the k effective of the reactor core. The inner region has a low moderator to fuel ratio such that the majority of fissions occurring therein are induced by neutrons having energies greater than thermal. The outer region has a high moderator to fuel ratio such that the majority of fissions occurring therein are induced by thermal neutrons. (AEC)

  4. NEUTRONIC REACTOR CORE INSTRUMENT

    DOEpatents

    Mims, L.S.

    1961-08-22

    A multi-purpose instrument for measuring neutron flux, coolant flow rate, and coolant temperature in a nuclear reactor is described. The device consists essentially of a hollow thimble containing a heat conducting element protruding from the inner wall, the element containing on its innermost end an amount of fissionsble materinl to function as a heat source when subjected to neutron flux irradiation. Thermocouple type temperature sensing means are placed on the heat conducting element adjacent the fissionable material and at a point spaced therefrom, and at a point on the thimble which is in contact with the coolant fluid. The temperature differentials measured between the thermocouples are determinative of the neutron flux, coolant flow, and temperature being measured. The device may be utilized as a probe or may be incorporated in a reactor core. (AE C)

  5. Neutronic reactor construction

    DOEpatents

    Huston, Norman E.

    1976-07-06

    1. A neutronic reactor comprising a moderator including horizontal layers formed of horizontal rows of graphite blocks, alternate layers of blocks having the rows extending in one direction, the remaining alternate layers having the rows extending transversely to the said one direction, alternate rows of blocks in one set of alternate layers having longitudinal ducts, the moderator further including slotted graphite tubes positioned in the ducts, the reactor further comprising an aluminum coolant tube positioned within the slotted tube in spaced relation thereto, bodies of thermal-neutron-fissionable material, and jackets enclosing the bodies and being formed of a corrosion-resistant material having a low neutron-capture cross section, the bodies and jackets being positioned within the coolant tube so that the jackets are spaced from the coolant tube.

  6. Nuclear reactor shutdown system

    DOEpatents

    Bhate, Suresh K.; Cooper, Martin H.; Riffe, Delmar R.; Kinney, Calvin L.

    1981-01-01

    An inherent shutdown system for a nuclear reactor having neutron absorbing rods affixed to an armature which is held in an upper position by a magnetic flux flowing through a Curie temperature material. The Curie temperature material is fixedly positioned about the exterior of an inner duct in an annular region through which reactor coolant flows. Elongated fuel rods extending from within the core upwardly toward the Curie temperature material are preferably disposed within the annular region. Upon abnormal conditions which result in high neutron flux and coolant temperature, the Curie material loses its magnetic permeability, breaking the magnetic flux path and allowing the armature and absorber rods to drop into the core, thus shutting down the fissioning reaction. The armature and absorber rods are retrieved by lowering the housing for the electromagnet forming coils which create a magnetic flux path which includes the inner duct wall. The coil housing then is raised, resetting the armature.

  7. In situ reactor

    DOEpatents

    Radtke, Corey William; Blackwelder, David Bradley

    2004-01-27

    An in situ reactor for use in a geological strata, is described and which includes a liner defining a centrally disposed passageway and which is placed in a borehole formed in the geological strata; and a sampling conduit is received within the passageway defined by the liner and which receives a geological specimen which is derived from the geological strata, and wherein the sampling conduit is in fluid communication with the passageway defined by the liner.

  8. BioReactor

    2003-04-18

    BioReactor is a simulation tool kit for modeling networks of coupled chemical processes (or similar productions rules). The tool kit is implemented in C++ and has the following functionality: 1. Monte Carlo discrete event simulator 2. Solvers for ordinary differential equations 3. Genetic algorithm optimization routines for reverse engineering of models using either Monte Carlo or ODE representation )i.e., 1 or 2)

  9. REACTOR MODERATOR STRUCTURE

    DOEpatents

    Greenstreet, B.L.

    1963-12-31

    A system for maintaining the alignment of moderator block structures in reactors is presented. Integral restraining grids are placed between each layer of blocks in the moderator structure, at the top of the uppermost layer, and at the bottom of the lowermost layer. Slots are provided in the top and bottom surfaces of the moderator blocks so as to provide a keying action with the grids. The grids are maintained in alignment by vertical guiding members disposed about their peripheries. (AEC)

  10. Nuclear reactor decontamination

    SciTech Connect

    Torok, J.

    1981-09-01

    Heat transfer and associated surfaces in nuclear reactors are decontaminated by treating the surface with ozone to oxidize acid -insoluble metal oxides to a more soluble state, removing oxidized solubilized metal oxides, and removing other surface oxides using low concentrations of decontaminating reagents. Ozone treatment has been found very effective with alloys having surface metal oxides rendered more easily dissolved by ozone oxidation especially with chromium or chromium-nickel containing alloys.

  11. Fissioning Plasma Core Reactor

    NASA Technical Reports Server (NTRS)

    Albright, Dennis; Butler, Carey; West, Nicole; Cole, John W. (Technical Monitor)

    2002-01-01

    Institute for Scientific Research, Inc. (ISR) research program consist of: 1.Study core physics by adapting existing codes: MCNP4C - Monte Carlo code; COMBINE/VENTURE - diffusion theory; SCALE4 - Monte Carlo, with many utility codes. 2. Determine feasibility and study major design parameters: fuel selection, temperature and reflector sizing. 3. Study reactor kinetics: develop QCALC1 to model point kinetics; study dynamic behavior of the power release.

  12. REACTOR CONTROL DEVICE

    DOEpatents

    Kaufman, H.B.; Weiss, A.A.

    1959-08-18

    A shadow control device for controlling a nuclear reactor is described. The device comprises a series of hollow neutron-absorbing elements arranged in groups, each element having a cavity for substantially housing an adjoining element and a longitudinal member for commonly supporting the groups of elements. Longitudinal actuation of the longitudinal member distributes the elements along its entire length in which position maximum worth is achieved.

  13. LOADING MACHINE FOR REACTORS

    DOEpatents

    Simon, S.L.

    1959-07-01

    An apparatus is described for loading or charging slugs of fissionable material into a nuclear reactor. The apparatus of the invention is a "muzzle loading" type comprising a delivery tube or muzzle designed to be brought into alignment with any one of a plurality of fuel channels. The delivery tube is located within the pressure shell and it is also disposed within shielding barriers while the fuel cantridges or slugs are forced through the delivery tube by an externally driven flexible ram.

  14. BOILER-SUPERHEATED REACTOR

    DOEpatents

    Heckman, T.P.

    1961-05-01

    A nuclear power reactor of the type in which a liquid moderator-coolant is transformed by nuclear heating into a vapor that may be used to drive a turbo- generator is described. The core of this reactor comprises a plurality of freely suspended tubular fuel elements, called fuel element trains, within which nonboiling pressurized liquid moderator-coolant is preheated and sprayed through orifices in the walls of the trains against the outer walls thereof to be converted into vapor. Passage of the vapor ovcr other unwetted portions of the outside of the fuel elements causes the steam to be superheated. The moderatorcoolant within the fuel elements remains in the liqUid state, and that between the fuel elements remains substantiaily in the vapor state. A unique liquid neutron-absorber control system is used. Advantages expected from the reactor design include reduced fuel element failure, increased stability of operation, direct response to power demand, and circulation of a minimum amount of liquid moderatorcoolant. (A.G.W.)

  15. Nuclear reactor sealing system

    DOEpatents

    McEdwards, James A.

    1983-01-01

    A liquid metal-cooled nuclear reactor sealing system. The nuclear reactor includes a vessel sealed at its upper end by a closure head. The closure head comprises at least two components, one of which is rotatable; and the two components define an annulus therebetween. The sealing system includes at least a first and second inflatable seal disposed in series in an upper portion of the annulus. The system further includes a dip seal extending into a body of insulation located adjacent a bottom portion of the closure head. The dip seal comprises a trough formed by a lower portion of one of the components, and a seal blade pendently supported from the other component and extending downwardly into the trough. A body of liquid metal is contained in the trough which submerges a portion of the seal blade. The seal blade is provided with at least one aperture located above the body of liquid metal for providing fluid communication between the annulus intermediate the dip seal and the inflatable seals, and a body of cover gas located inside the vessel. There also is provided means for introducing a purge gas into the annulus intermediate the inflatable seals and the seal blade. The purge gas is introduced in an amount sufficient to substantially reduce diffusion of radioactive cover gas or sodium vapor up to the inflatable seals. The purge gas mixes with the cover gas in the reactor vessel where it can be withdrawn from the vessel for treatment and recycle to the vessel.

  16. NUCLEAR REACTOR CORE DESIGN

    DOEpatents

    Mahlmeister, J.E.; Peck, W.S.; Haberer, W.V.; Williams, A.C.

    1960-03-22

    An improved core design for a sodium-cooled, graphitemoderated nuclear reactor is described. The improved reactor core comprises a number of blocks of moderator material, each block being in the shape of a regular prism. A number of channels, extending the length of each block, are disposed around the periphery. When several blocks are placed in contact to form the reactor core, the channels in adjacent blocks correspond with each other to form closed conduits extending the length of the core. Fuel element clusters are disposed in these closed conduits, and liquid coolant is forced through the annulus between the fuel cluster and the inner surface of the conduit. In a preferred embodiment of the invention, the moderator blocks are in the form of hexagonal prisms with longitudinal channels cut into the corners of the hexagon. The main advantage of an "edge-loaded" moderator block is that fewer thermal neutrons are absorbed by the moderator cladding, as compared with a conventional centrally loaded moderator block.

  17. COMPARTMENTED REACTOR FUEL ELEMENT

    DOEpatents

    Cain, F.M. Jr.

    1962-09-11

    A method of making a nuclear reactor fuel element of the elongated red type is given wherein the fissionable fuel material is enclosed within a tubular metal cladding. The method comprises coating the metal cladding tube on its inside wall with a brazing alloy, inserting groups of cylindrical pellets of fissionable fuel material into the tube with spacing members between adjacent groups of pellets, sealing the ends of the tubes to leave a void space therewithin, heating the tube and its contents to an elevated temperature to melt the brazing alloy and to expand the pellets to their maximum dimensions under predetermined operating conditions thereby automatically positioning the spacing members along the tube, and finally cooling the tube to room temperature whereby the spacing disks become permanently fixed at their edges in the brazing alloy and define a hermetically sealed compartment for each fl group of fuel pellets. Upon cooling, the pellets contract thus leaving a space to accommodate thermal expansion of the pellets when in use in a reactor. The spacing members also provide lateral support for the tubular cladding to prevent collapse thereof when subjected to a reactor environment. (AEC)

  18. Thermionic Reactor Design Studies

    SciTech Connect

    Schock, Alfred

    1994-06-01

    During the 1960's and early 70's the author performed extensive design studies, analyses, and tests aimed at thermionic reactor concepts that differed significantly from those pursued by other investigators. Those studies, like most others under Atomic Energy Commission (AEC and DOE) and the National Aeronautics and Space Administration (NASA) sponsorship, were terminated in the early 1970's. Some of this work was previously published, but much of it was never made available in the open literature. U.S. interest in thermionic reactors resumed in the early 80's, and was greatly intensified by reports about Soviet ground and flight tests in the late 80's. This recent interest resulted in renewed U.S. thermionic reactor development programs, primarily under Department of Defense (DOD) and Department of Energy (DOE) sponsorship. Since most current investigators have not had an opportunity to study all of the author's previous work, a review of the highlights of that work may be of value to them. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling. Where the author's concepts differed from the later Topaz-2 design was in the relative location of the emitter and the collector. Placing the fueled emitter on the outside of the cylindrical diodes permits much higher axial conductances to reduce ohmic losses in the electrodes of full

  19. The molten salt reactor adventure

    SciTech Connect

    MacPherson, H.G.

    1985-08-01

    A personal history of the development of molten salt reactors in the United States is presented. The initial goal was an aircraft propulsion reactor, and a molten fluoride-fueled Aircraft Reactor Experiment was operated at Oak Ridge National Laboratory in 1954. In 1956, the objective shifted to civilian nuclear power, and reactor concepts were developed using a circulating UF4-ThF4 fuel, graphite moderator, and Hastelloy N pressure boundary. The program culminated in the successful operation of the Molten Salt Reactor Experiment in 1965 to 1969. By then the Atomic Energy Commission's goals had shifted to breeder development; the molten salt program supported on-site reprocessing development and study of various reactor arrangements that had potential to breed. Some commercial and foreign interest contributed to the program which, however, was terminated by the government in 1976. The current status of the technology and prospects for revived interest are summarized.

  20. Acceptability of reactors in space

    SciTech Connect

    Buden, D.

    1981-01-01

    Reactors are the key to our future expansion into space. However, there has been some confusion in the public as to whether they are a safe and acceptable technology for use in space. The answer to these questions is explored. The US position is that when reactors are the preferred technical choice, that they can be used safely. In fact, it does not appear that reactors add measurably to the risk associated with the Space Transportation System.

  1. Fast quench reactor and method

    DOEpatents

    Detering, B.A.; Donaldson, A.D.; Fincke, J.R.; Kong, P.C.

    1998-05-12

    A fast quench reactor includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a restrictive convergent-divergent nozzle at its outlet end. Reactants are injected into the reactor chamber. The resulting heated gaseous stream is then rapidly cooled by passage through the nozzle. This ``freezes`` the desired end product(s) in the heated equilibrium reaction stage. 7 figs.

  2. Turning points in reactor design

    SciTech Connect

    Beckjord, E.S.

    1995-09-01

    This article provides some historical aspects on nuclear reactor design, beginning with PWR development for Naval Propulsion and the first commercial application at Yankee Rowe. Five turning points in reactor design and some safety problems associated with them are reviewed: (1) stability of Dresden-1, (2) ECCS, (3) PRA, (4) TMI-2, and (5) advanced passive LWR designs. While the emphasis is on the thermal-hydraulic aspects, the discussion is also about reactor systems.

  3. Acceptability of reactors in space

    SciTech Connect

    Buden, D.

    1981-04-01

    Reactors are the key to our future expansion into space. However, there has been some confusion in the public as to whether they are a safe and acceptable technology for use in space. The answer to these questions is explored. The US position is that when reactors are the preferred technical choice, that they can be used safely. In fact, it dies not appear that reactors add measurably to the risk associated with the Space Transportation System.

  4. Neutrino oscillation studies with reactors.

    PubMed

    Vogel, P; Wen, L J; Zhang, C

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos. PMID:25913819

  5. Neutrino oscillation studies with reactors.

    PubMed

    Vogel, P; Wen, L J; Zhang, C

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  6. Neutrino oscillation studies with reactors

    SciTech Connect

    Vogel, P.; Wen, L.J.; Zhang, C.

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  7. Neutrino oscillation studies with reactors

    DOE PAGES

    Vogel, P.; Wen, L.J.; Zhang, C.

    2015-04-27

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos.

  8. NEUTRONIC REACTOR CHARGING AND DISCHARGING

    DOEpatents

    Zinn, W.H.

    1959-07-14

    A method and arrangement is presented for removing a fuel element from a neutronic reactor tube through which a liquid coolant is being circulaled. The fuel element is moved into a section of the tube beyond the reactor proper, and then the coolant in the tube between the fuel element and the reactor proper is frozen, so that the fuel element may be removed from the tube without loss of the coolant therein. The method is particularly useful in the case of a liquid metal- cooled reactor.

  9. Neutrino oscillation studies with reactors

    PubMed Central

    Vogel, P.; Wen, L.J.; Zhang, C.

    2015-01-01

    Nuclear reactors are one of the most intense, pure, controllable, cost-effective and well-understood sources of neutrinos. Reactors have played a major role in the study of neutrino oscillations, a phenomenon that indicates that neutrinos have mass and that neutrino flavours are quantum mechanical mixtures. Over the past several decades, reactors were used in the discovery of neutrinos, were crucial in solving the solar neutrino puzzle, and allowed the determination of the smallest mixing angle θ13. In the near future, reactors will help to determine the neutrino mass hierarchy and to solve the puzzling issue of sterile neutrinos. PMID:25913819

  10. Integration of the Ultraviolet-Visible Spectral Clementine Data and the Gamma-Ray Lunar Prospector Data: Preliminary Results Concerning FeO, TiO2, and Th Abundances of the Lunar Surface at Global Scale

    NASA Astrophysics Data System (ADS)

    Chevrel, S. D.; Pinet, P. C.; Barreau, G.; Daydou, Y.; Richard, G.; Maurice, S.; Feldman, W. C.

    1999-01-01

    The Clementine mission (CLM) produced global multispectral data that resulted in a map of FeO and Ti02 concentrations of the lunar surface. The recent Lunar Prospector (LP) mission returned the first global data for the distribution of surface abundances of key elements in lunar rocks, using a gamma-ray spectrometer (GRS) and neutron spectrometer(NS). Integrating CLM mineralogical spectral reflectance and LP chemical data is important to enhance our view of lunar crust origin and evolution, lunar volcanism, and surface processes. Iron, Ti, and Th having relatively large compositional variation over the lunar surface, as well as strong isolated peaks in the GRS spectra, information concerning the distribution and concentration of these elements has been derived from maps of corrected (cosmic ray, nonsymmetric response of the instrument) counting rates only, without converting them into absolute abundances. Maps produced contain count rates in equal-area projection averaged into 5 x 5 degrees latitude/longitude bins, from -90 to +90 degrees latitude and -180 to +180 degrees longitude. In this work, we have used the CLM global FeO and Ti02 abundances (wt%) maps converted at the LP spatial resolution (about 150 km/pixel) to produce FeO and TiO2 GRS abundance maps, through a linear regression based on the analysis of the scatter distribution of both datasets. The regression coefficients have been determined from the data taken between -60 and +60 degrees latitude to avoid uncertainties in the CLM spectral data due to nonnominal conditions of observation at high latitudes. After a critical assessment of the validity of these coefficients for every class of absolute abundance, the LP data have been transformed into absolute abundances for the whole Moon. The Th LP data have been converted into abundances (ppm) using Th concentrations in average soils from the Apollo and Luna sites given. Values of Th abundances for these samples range between 0.5 and 13 ppm. A nonlinear

  11. Reactor operations informal report, October 1994

    SciTech Connect

    Hauptman, H.M.; Petro, J.N.; Jacobi, O.; Lettieri, V.; Holden, N.; Ports, D.; Petricek, R.

    1994-10-01

    This monthly progress report is divided into two parts. Part one covers the Brookhaven Medical Research Reactor and part two covers the Brookhaven High Flux Beam Reactor. Information is given for each reactor covering the following areas: reactor operation; instrumentation; mechanical maintenance; occurrence reports; and reactor safety.

  12. Transport Reactor Facility

    SciTech Connect

    Berry, D.A.; Shoemaker, S.A.

    1996-12-31

    The Morgantown Energy Technology Center (METC) is currently evaluating hot gas desulfurization (HGD)in its on-site transport reactor facility (TRF). This facility was originally constructed in the early 1980s to explore advanced gasification processes with an entrained reactor, and has recently been modified to incorporate a transport riser reactor. The TRF supports Integrated Gasification Combined Cycle (IGCC) power systems, one of METC`s advanced power generation systems. The HGD subsystem is a key developmental item in reducing the cost and increasing the efficiency of the IGCC concept. The TRF is a unique facility with high-temperature, high-pressure, and multiple reactant gas composition capability. The TRF can be configured for reacting a single flow pass of gas and solids using a variety of gases. The gas input system allows six different gas inputs to be mixed and heated before entering the reaction zones. Current configurations allow the use of air, carbon dioxide, carbon monoxide, hydrogen, hydrogen sulfide, methane, nitrogen, oxygen, steam, or any mixture of these gases. Construction plans include the addition of a coal gas input line. This line will bring hot coal gas from the existing Fluidized-Bed Gasifier (FBG) via the Modular Gas Cleanup Rig (MGCR) after filtering out particulates with ceramic candle filters. Solids can be fed either by a rotary pocket feeder or a screw feeder. Particle sizes may range from 70 to 150 micrometers. Both feeders have a hopper that can hold enough solid for fairly lengthy tests at the higher feed rates, thus eliminating the need for lockhopper transfers during operation.

  13. Rotating reactor studies

    NASA Technical Reports Server (NTRS)

    Roberts, Glyn O.

    1991-01-01

    Undesired gravitational effects such as convection or sedimentation in a fluid can sometimes be avoided or decreased by the use of a closed chamber uniformly rotated about a horizontal axis. In a previous study, the spiral orbits of a heavy or buoyant particle in a uniformly rotating fluid were determined. The particles move in circles, and spiral in or out under the combined effects of the centrifugal force and centrifugal buoyancy. A optimization problem for the rotation rate of a cylindrical reactor rotated about its axis and containing distributed particles was formulated and solved. Related studies in several areas are addressed. A computer program based on the analysis was upgraded by correcting some minor errors, adding a sophisticated screen-and-printer graphics capability and other output options, and by improving the automation. The design, performance, and analysis of a series of experiments with monodisperse polystyrene latex microspheres in water were supported to test the theory and its limitations. The theory was amply confirmed at high rotation rates. However, at low rotation rates (1 rpm or less) the assumption of uniform solid-body rotation of the fluid became invalid, and there were increasingly strong secondary motions driven by variations in the mean fluid density due to variations in the particle concentration. In these tests the increase in the mean fluid density due to the particles was of order 0.015 percent. To a first approximation, these flows are driven by the buoyancy in a thin crescent-shaped depleted layer on the descending side of the rotating reactor. This buoyancy distribution is balanced by viscosity near the walls, and by the Coriolis force in the interior. A full analysis is beyond the scope of this study. Secondary flows are likely to be stronger for buoyant particles, which spiral in towards the neutral point near the rotation axis under the influence of their centrifugal buoyancy. This is because the depleted layer is

  14. SODIUM DEUTERIUM REACTOR

    DOEpatents

    Oppenheimer, E.D.; Weisberg, R.A.

    1963-02-26

    This patent relates to a barrier system for a sodium heavy water reactor capable of insuring absolute separation of the metal and water. Relatively cold D/sub 2/O moderator and reflector is contained in a calandria into which is immersed the fuel containing tubes. The fuel elements are cooled by the sodium which flows within the tubes and surrounds the fuel elements. The fuel containing tubes are surrounded by concentric barrier tubes forming annular spaces through which pass inert gases at substantially atmospheric pressure. Header rooms above and below the calandria are provided for supplying and withdrawing the sodium and inert gases in the calandria region. (AEC)

  15. FUEL ASSAY REACTOR

    DOEpatents

    Spinrad, B.I.; Sandmeier, H.A.; Martens, F.H.

    1962-12-25

    A reactor having maximum sensitivity to perturbations is described comprising a core consisting of a horizontally disposed, rectangular, annular fuel zone containing enriched uranium dioxide dispersed in graphite, the concentration of uranium dioxide increasing from the outside to the inside of the fuel zone, an internal reflector of graphite containing an axial test opening disposed within the fuel zone, an external graphite reflector, means for changing the neutron spectrum in the test opening, and means for measuring perturbations in the neutron flux caused by the introduction of different fuel elements into the test opening. (AEC)

  16. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.; Marasco, Joseph A.

    1996-01-01

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves.

  17. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.

    1993-01-01

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  18. Biparticle fluidized bed reactor

    DOEpatents

    Scott, Charles D.; Marasco, Joseph A.

    1995-01-01

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  19. High flux reactor

    DOEpatents

    Lake, James A.; Heath, Russell L.; Liebenthal, John L.; DeBoisblanc, Deslonde R.; Leyse, Carl F.; Parsons, Kent; Ryskamp, John M.; Wadkins, Robert P.; Harker, Yale D.; Fillmore, Gary N.; Oh, Chang H.

    1988-01-01

    A high flux reactor is comprised of a core which is divided into two symetric segments housed in a pressure vessel. The core segments include at least one radial fuel plate. The spacing between the plates functions as a coolant flow channel. The core segments are spaced axially apart such that a coolant mixing plenum is formed between them. A channel is provided such that a portion of the coolant bypasses the first core section and goes directly into the mixing plenum. The outlet coolant from the first core segment is mixed with the bypass coolant resulting in a lower inlet temperature to the lower core segment.

  20. FOOD IRRADIATION REACTOR

    DOEpatents

    Leyse, C.F.; Putnam, G.E.

    1961-05-01

    An irradiation apparatus is described. It comprises a pressure vessel, a neutronic reactor active portion having a substantially greater height than diameter in the pressure vessel, an annular tank surrounding and spaced from the pressure vessel containing an aqueous indium/sup 1//sup 1//sup 5/ sulfate solution of approximately 600 grams per liter concentration, means for circulating separate coolants through the active portion and the space between the annular tank and the pressure vessel, radiator means adapted to receive the materials to be irradiated, and means for flowing the indium/sup 1//sup 1//sup 5/ sulfate solution through the radiator means.

  1. NEUTRONIC REACTOR CONSTRUCTION

    DOEpatents

    Vernon, H.C.; Goett, J.J.

    1958-09-01

    A cover device is described for the fuel element receiving tube of a neutronic reactor of the heterogeneous, water cooled type wherein said tubes are arranged in a moderator with their longitudinal axes vertical. The cover is provided with means to support a rod-type fuel element from the bottom thereof and means to lock the cover in place, the latter being adapted for remote operation. This cover device is easily removable and seals the opening in the upper end of the fuel tube against leakage of coolant.

  2. REACTOR COOLANT TUBE SEAL

    DOEpatents

    Morris, W.J.

    1958-12-01

    A plle-flattenlng control element and a fluid seal therefore to permit movement of the element into a liquld contnining region of a neutronlc reactor are described. The device consists of flattened, thin-walled aluminum tubing contalnlng a uniform mixture of thermal neutron absorbing material, and a number of soft rubber closures for the process tubes, having silts capable of passing the flattened elements therethrough, but effectively sealing the process tubes against fluld leaknge by compression of the rubber. The flattened tubing is sufficiently flexible to enable it to conform to the configuratlon of the annular spacing surrounding the fuel elements ln the process tubes.

  3. Nuclear reactor control apparatus

    DOEpatents

    Sridhar, Bettadapur N.

    1983-11-01

    Nuclear reactor core safety rod release apparatus comprises a control rod having a detent notch in the form of an annular peripheral recess at its upper end, a control rod support tube for raising and lowering the control rod under normal conditions, latches pivotally mounted on the control support tube with free ends thereof normally disposed in the recess in the control rod, and cam means for pivoting the latches out of the recess in the control rod when a scram condition occurs. One embodiment of the invention comprises an additional magnetically-operated latch for releasing the control rod under two different conditions, one involving seismic shock.

  4. Reactor refueling containment system

    DOEpatents

    Gillett, James E.; Meuschke, Robert E.

    1995-01-01

    A method of refueling a nuclear reactor whereby the drive mechanism is disengaged and removed by activating a jacking mechanism that raises the closure head. The area between the barrier plate and closure head is exhausted through the closure head penetrations. The closure head, upper drive mechanism, and bellows seal are lifted away and transported to a safe area. The barrier plate acts as the primary boundary and each drive and control rod penetration has an elastomer seal preventing excessive tritium gases from escaping. The individual instrumentation plugs are disengaged allowing the corresponding fuel assembly to be sealed and replaced.

  5. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.

    1993-12-14

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  6. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.; Marasco, J.A.

    1996-02-27

    A fluidized bed reactor system is described which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves. 3 figs.

  7. Reactor refueling containment system

    DOEpatents

    Gillett, J.E.; Meuschke, R.E.

    1995-05-02

    A method of refueling a nuclear reactor is disclosed whereby the drive mechanism is disengaged and removed by activating a jacking mechanism that raises the closure head. The area between the barrier plate and closure head is exhausted through the closure head penetrations. The closure head, upper drive mechanism, and bellows seal are lifted away and transported to a safe area. The barrier plate acts as the primary boundary and each drive and control rod penetration has an elastomer seal preventing excessive tritium gases from escaping. The individual instrumentation plugs are disengaged allowing the corresponding fuel assembly to be sealed and replaced. 2 figs.

  8. Biparticle fluidized bed reactor

    DOEpatents

    Scott, C.D.; Marasco, J.A.

    1995-04-25

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figs.

  9. PINCHED PLASMA REACTOR

    DOEpatents

    Phillips, J.A.; Suydam, R.; Tuck, J.L.

    1961-07-01

    BS>A plasma confining and heating reactor is described which has the form of a torus with a B/sub 2/ producing winding on the outside of the torus and a helical winding of insulated overlapping tunns on the inside of the torus. The inner helical winding performs the double function of shielding the plasma from the vitreous container and generating a second B/sub z/ field in the opposite direction to the first B/sub z/ field after the pinch is established.

  10. Reactor coolant pump flywheel

    SciTech Connect

    Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

    2013-11-26

    A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

  11. Nuclear reactor fuel element

    DOEpatents

    Johnson, Carl E.; Crouthamel, Carl E.

    1980-01-01

    A nuclear reactor fuel element is described which has an outer cladding, a central core of fissionable or mixed fissionable and fertile fuel material and a layer of oxygen gettering material on the inner surface of the cladding. The gettering material reacts with oxygen released by the fissionable material during irradiation of the core thereby preventing the oxygen from reacting with and corroding the cladding. Also described is an improved method for coating the inner surface of the cladding with a layer of gettering material.

  12. FAST NEUTRONIC REACTOR

    DOEpatents

    Snell, A.H.

    1957-12-01

    This patent relates to a reactor and process for carrying out a controlled fast neutron chain reaction. A cubical reactive mass, weighing at least 920 metric tons, of uranium metal containing predominantly U/sup 238/ and having a U/sup 235/ content of at least 7.63% is assembled and the maximum neutron reproduction ratio is limited to not substantially over 1.01 by insertion and removal of a varying amount of boron, the reactive mass being substantially freed of moderator.

  13. POWER BREEDER REACTOR

    DOEpatents

    Monson, H.O.

    1960-11-22

    An arrangement is offered for preventing or minimizing the contraction due to temperature rise, of a reactor core comprising vertical fuel rods in sodium. Temperature rise of the fuel rods would normally make them move closer together by inward bowing, with a resultant undesired increase in reactivity. According to the present invention, assemblies of the fuel rods are laterally restrained at the lower ends of their lower blanket sections and just above the middle of the fuel sections proper of the rods, and thus the fuel sections move apart, rather than together, with increase in temperature.

  14. Licensed reactor nuclear safety criteria applicable to DOE reactors

    SciTech Connect

    Not Available

    1991-04-01

    The Department of Energy (DOE) Order DOE 5480.6, Safety of Department of Energy-Owned Nuclear Reactors, establishes reactor safety requirements to assure that reactors are sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that adequately protects health and safety and is in accordance with uniform standards, guides, and codes which are consistent with those applied to comparable licensed reactors. This document identifies nuclear safety criteria applied to NRC (Nuclear Regulatory Commission) licensed reactors. The titles of the chapters and sections of USNRC Regulatory Guide 1.70, Standard Format and Content of Safety Analysis Reports for Nuclear Power Plants, Rev. 3, are used as the format for compiling the NRC criteria applied to the various areas of nuclear safety addressed in a safety analysis report for a nuclear reactor. In each section the criteria are compiled in four groups: (1) Code of Federal Regulations, (2) US NRC Regulatory Guides, SRP Branch Technical Positions and Appendices, (3) Codes and Standards, and (4) Supplemental Information. The degree of application of these criteria to a DOE-owned reactor, consistent with their application to comparable licensed reactors, must be determined by the DOE and DOE contractor.

  15. Reactor system for upgrading light olefins in staged reactors

    SciTech Connect

    Harandi, M.N.; Owen, H.

    1991-05-28

    This patent describes a semicontinuous multistage catalytic system for conversion of light olefinic gas feedstock to distillate range hydrocarbons. It comprises: a first reactor means; means for passing hot feedstock vapor upwardly; fluid handling means; means for recovering from primary stage effluent stream; second reactor means; and fluid handling means for periodically interrupting flow.

  16. Fast Reactor Fuel Type and Reactor Safety Performance

    SciTech Connect

    R. Wigeland; J. Cahalan

    2009-09-01

    Fast Reactor Fuel Type and Reactor Safety Performance R. Wigeland , Idaho National Laboratory J. Cahalan, Argonne National Laboratory The sodium-cooled fast neutron reactor is currently being evaluated for the efficient transmutation of the highly-hazardous, long-lived, transuranic elements that are present in spent nuclear fuel. One of the fundamental choices that will be made is the selection of the fuel type for the fast reactor, whether oxide, metal, carbide, nitride, etc. It is likely that a decision on the fuel type will need to be made before many of the related technologies and facilities can be selected, from fuel fabrication to spent fuel reprocessing. A decision on fuel type should consider all impacts on the fast reactor system, including safety. Past work has demonstrated that the choice of fuel type may have a significant impact on the severity of consequences arising from accidents, especially for severe accidents of low probability. In this paper, the response of sodium-cooled fast reactors is discussed for both oxide and metal fuel types, highlighting the similarities and differences in reactor response and accident consequences. Any fast reactor facility must be designed to be able to successfully prevent, mitigate, or accommodate all consequences of potential events, including accidents. This is typically accomplished by using multiple barriers to the release of radiation, including the cladding on the fuel, the intact primary cooling system, and most visibly the reactor containment building. More recently, this has also included the use of ‘inherent safety’ concepts to reduce or eliminate the potential for serious damage in some cases. Past experience with oxide and metal fuel has demonstrated that both fuel types are suitable for use as fuel in a sodium-cooled fast reactor. However, safety analyses for these two fuel types have also shown that there can be substantial differences in accident consequences due to the neutronic and

  17. NEUTRONIC REACTOR CORE

    DOEpatents

    Thomson, W.B.; Corbin, A. Jr.

    1961-07-18

    An improved core for a gas-cooled power reactor which admits gas coolant at high temperatures while affording strong integral supporting structure and efficient moderation of neutrons is described. The multiplicities of fuel elements constituting the critical amassment of fissionable material are supported and confined by a matrix of metallic structure which is interspersed therebetween. Thermal insulation is interposed between substantially all of the metallic matrix and the fuel elements; the insulation then defines the principal conduit system for conducting the coolant gas in heat-transfer relationship with the fuel elements. The metallic matrix itseif comprises a system of ducts through which an externally-cooled hydrogeneous liquid, such as water, is circulated to serve as the principal neutron moderant for the core and conjointly as the principal coolant for the insulated metallic structure. In this way, use of substantially neutron transparent metals, such as aluminum, becomes possible for the supporting structure, despite the high temperatures of the proximate gas. The Aircraft Nuclear Propulsion program's "R-1" reactor design is a preferred embodiment.

  18. Reactor Operations informal monthly report December 1994

    SciTech Connect

    1994-12-01

    Reactor operations at the MRR and HFBR reactors at Brookhaven National Laboratory are presented for December 1994. Reactor run-time and power levels, instrumentation, mechanical maintenance, occurrence reports, and safety information are included.

  19. Reactor production of Thorium-229

    DOE PAGES

    Boll, Rose Ann; Murphy, Karen E.; Denton, David L.; Tamara J. Haverlock; Garland, Marc A.; Mirzadeh, Saed; Hogle, Susan; Owens, Allison

    2016-05-03

    Limited availability of 229Th for clinical applications of 213Bi necessitates investigation of alternative production routes. In reactor production, 229Th is produced from neutron transmutation of 226Ra, 228Ra, 227Ac and 228Th. Here, we evaluate irradiations of 226Ra, 228Ra, and 227Ac targets at the ORNL High Flux Isotope Reactor.

  20. Reactor production of Thoruim-229

    DOE PAGES

    Boll, Rose Ann; Murphy, Karen E.; Denton, David L.; Tamara J. Haverlock; Garland, Marc A.; Mirzadeh, Saed; Hogle, Susan; Owens, Allison

    2016-05-03

    Limited availability of 229Th for clinical applications of 213Bi necessitates investigation of alternative production routes. In reactor production, 229Th is produced from neutron transmutation of 226Ra, 228Ra, 227Ac and 228Th. Here, we evaluate irradiations of 226Ra, 228Ra, and 227Ac targets at the ORNL High Flux Isotope Reactor.

  1. Chemical-vapor-deposition reactor

    NASA Technical Reports Server (NTRS)

    Chern, S.

    1979-01-01

    Reactor utilizes multiple stacked trays compactly arranged in paths of horizontally channeled reactant gas streams. Design allows faster and more efficient deposits of film on substrates, and reduces gas and energy consumption. Lack of dead spots that trap reactive gases reduces reactor purge time.

  2. The International Reactor Dosimetry File.

    1994-01-19

    Version 01 The International Reactor Dosimetry File (IRDF-90) contains recommended neutron cross-section data to be used for reactor neutron dosimetry by foil activation. It also contains selected recommended values for radiation damage cross-sections and benchmark neutron spectra. This library supersedes all earlier versions of IRDF.

  3. Proton Collimators for Fusion Reactors

    NASA Technical Reports Server (NTRS)

    Miley, George H.; Momota, Hiromu

    2003-01-01

    Proton collimators have been proposed for incorporation into inertial-electrostatic-confinement (IEC) fusion reactors. Such reactors have been envisioned as thrusters and sources of electric power for spacecraft and as sources of energetic protons in commercial ion-beam applications.

  4. Solvent refined coal reactor quench system

    DOEpatents

    Thorogood, R.M.

    1983-11-08

    There is described an improved SRC reactor quench system using a condensed product which is recycled to the reactor and provides cooling by evaporation. In the process, the second and subsequent reactors of a series of reactors are cooled by the addition of a light oil fraction which provides cooling by evaporation in the reactor. The vaporized quench liquid is recondensed from the reactor outlet vapor stream. 1 fig.

  5. Solvent refined coal reactor quench system

    DOEpatents

    Thorogood, Robert M.

    1983-01-01

    There is described an improved SRC reactor quench system using a condensed product which is recycled to the reactor and provides cooling by evaporation. In the process, the second and subsequent reactors of a series of reactors are cooled by the addition of a light oil fraction which provides cooling by evaporation in the reactor. The vaporized quench liquid is recondensed from the reactor outlet vapor stream.

  6. Reactor-Produced Medical Radionuclides

    SciTech Connect

    Mirzadeh, Saed; Mausner, Leonard; Garland, Marc A

    2011-01-01

    The therapeutic use of radionuclides in nuclear medicine, oncology and cardiology is the most rapidly growing use of medical radionuclides. Since most therapeutic radionuclides are neutron rich and decay by beta emission, they are reactor-produced. This chapter deals mainly with production approaches with neutrons. Neutron interactions with matter, neutron transmission and activation rates, and neutron spectra of nuclear reactors are discussed in some detail. Further, a short discussion of the neutron-energy dependence of cross sections, reaction rates in thermal reactors, cross section measurements and flux monitoring, and general equations governing the reactor production of radionuclides are presented. Finally, the chapter is concluded by providing a number of examples encompassing the various possible reaction routes for production of a number of medical radionuclides in a reactor.

  7. Fast reactors and nuclear nonproliferation

    SciTech Connect

    Avrorin, E.N.; Rachkov, V.I.; Chebeskov, A.N.

    2013-07-01

    Problems are discussed with regard to nuclear fuel cycle resistance in fast reactors to nuclear proliferation risk due to the potential for use in military programs of the knowledge, technologies and materials gained from peaceful nuclear power applications. Advantages are addressed for fast reactors in the creation of a more reliable mode of nonproliferation in the closed nuclear fuel cycle in comparison with the existing fully open and partially closed fuel cycles of thermal reactors. Advantages and shortcomings are also discussed from the point of view of nonproliferation from the start with fast reactors using plutonium of thermal reactor spent fuel and enriched uranium fuel to the gradual transition using their own plutonium as fuel. (authors)

  8. Nuclear Reactor Kinetics and Control.

    2009-07-27

    Version 00 Dr. J.D. Lewins has now released the following legacy book for free distribution: Nuclear Reactor Kinetics and Control, Pergamon Press, London, 275 pages, 1978. 1. Introductory Review 2. Neutron and Precursor Equations 3. Elementary Solutions of the Kinetics Equations at Low Power 4. Linear Reactor Process Dynamics with Feedback 5. Power Reactor Control Systems 6. Fluctuations and Reactor Noise 7. Safety and Reliability 8. Non Linear Systems; Stability and Control 9. Analogue Computingmore » Addendum: Jay Basken and Jeffery D. Lewins: Power Series Solution of the Reactor Kinetics Equations, Nuclear Science and Engineering: 122, 407-436 (1996) (authorized for distribution with the book: courtesy of the American Nuclear Society)« less

  9. RADIATION FACILITY FOR NUCLEAR REACTORS

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1961-12-12

    A radiation facility is designed for irradiating samples in close proximity to the core of a nuclear reactor. The facility comprises essentially a tubular member extending through the biological shield of the reactor and containing a manipulatable rod having the sample carrier at its inner end, the carrier being longitudinally movable from a position in close proximity to the reactor core to a position between the inner and outer faces of the shield. Shield plugs are provided within the tubular member to prevent direct radiation from the core emanating therethrough. In this device, samples may be inserted or removed during normal operation of the reactor without exposing personnel to direct radiation from the reactor core. A storage chamber is also provided within the radiation facility to contain an irradiated sample during the period of time required to reduce the radioactivity enough to permit removal of the sample for external handling. (AEC)

  10. Temperature effects on chemical reactor

    NASA Astrophysics Data System (ADS)

    Azzouzi, M.

    2008-06-01

    In this paper we had to study some characteristics of the chemical reactors, from which we can understand the reactor operation in different circumstances; from these and the most important factor that has a great effect on the reactor operation is the temperature, it is a mathematical processing of a chemical problem that was already studied, but it may be developed by introducing new strategies of control; in our case we deal with the analysis of a liquid-gas reactor which can make the flotation of the benzene to produce the ethylene; this type of reactors can be used in vast domains of the chemical industry, especially in refinery plants where we find the oil separation and its extractions whether they are gases or liquids which become necessary for industrial technology, especially in our century.

  11. Reactor for making uniform capsules

    NASA Technical Reports Server (NTRS)

    Wang, Taylor G. (Inventor); Anikumar, Amrutur V. (Inventor); Lacik, Igor (Inventor)

    1999-01-01

    The present invention provides a novel reactor for making capsules with uniform membrane. The reactor includes a source for providing a continuous flow of a first liquid through the reactor; a source for delivering a steady stream of drops of a second liquid to the entrance of the reactor; a main tube portion having at least one loop, and an exit opening, where the exit opening is at a height substantially equal to the entrance. In addition, a method for using the novel reactor is provided. This method involves providing a continuous stream of a first liquid; introducing uniformly-sized drops of the second liquid into the stream of the first liquid; allowing the drops to react in the stream for a pre-determined period of time; and collecting the capsules.

  12. Neutrino Experiments at Reactors

    DOE R&D Accomplishments Database

    Reines, F.; Gurr, H. S.; Jenkins, T. L.; Munsee, J. H.

    1968-09-09

    A description is given of the electron-antineutrino program using a large fission reactor. A search has been made for a neutral weak interaction via the reaction (electron antineutrino + d .> p + n + electron antineutrino), the reaction (electron antineutrino + d .> n + n + e{sup +}) has now been detected, and an effort is underway to observe the elastic scattering reaction (electron antineutrino + e{sup -} .> electron antineutrino + e{sup -}) as well as to measure more precisely the reaction (electron antineutrino + p .> n + e{sup+}). The upper limit on the elastic scattering reaction which we have obtained with our large composite NaI, plastic, liquid scintillation detector is now about 50 times the predicted value.

  13. FLUID MODERATED REACTOR

    DOEpatents

    Wigner, E.P.; Ohlinger, L.A.; Young, G.J.; Weinberg, A.M.

    1957-10-22

    A reactor which utilizes fissionable fuel elements in rod form immersed in a moderator or heavy water and a means of circulating the heavy water so that it may also function as a coolant to remove the heat generated by the fission of the fuel are described. In this design, the clad fuel elements are held in vertical tubes immersed in heavy water in a tank. The water is circulated in a closed system by entering near the tops of the tubes, passing downward through the tubes over the fuel elements and out into the tank, where it is drawn off at the bottom, passed through heat exchangers to give up its heat and then returned to the tops of the tubes for recirculation.

  14. GAS COOLED NUCLEAR REACTORS

    DOEpatents

    Long, E.; Rodwell, W.

    1958-06-10

    A gas-cooled nuclear reactor consisting of a graphite reacting core and reflector structure supported in a containing vessel is described. A gas sealing means is included for sealing between the walls of the graphite structure and containing vessel to prevent the gas coolant by-passing the reacting core. The reacting core is a multi-sided right prismatic structure having a pair of parallel slots around its periphery. The containing vessel is cylindrical and has a rib on its internal surface which supports two continuous ring shaped flexible web members with their radially innermost ends in sealing engagement within the radially outermost portion of the slots. The core structure is supported on ball bearings. This design permits thermal expansion of the core stracture and vessel while maintainirg a peripheral seal between the tvo elements.

  15. Nuclear reactor control

    DOEpatents

    Cawley, William E.; Warnick, Robert F.

    1982-01-01

    1. In a nuclear reactor incorporating a plurality of columns of tubular fuel elements disposed in horizontal tubes in a mass of graphite wherein water flows through the tubes to cool the fuel elements, the improvement comprising at least one control column disposed in a horizontal tube including fewer fuel elements than in a normal column of fuel elements and tubular control elements disposed at both ends of said control column, and means for varying the horizontal displacement of the control column comprising a winch at the upstream end of the control column and a cable extending through the fuel and control elements and attached to the element at the downstream end of the column.

  16. REACTOR MODERATOR STRUCTURE

    DOEpatents

    Fraas, A.P.; Tudor, J.J.

    1963-08-01

    An improved moderator structure for nuclear reactors consists of moderator blocks arranged in horizontal layers to form a multiplicity of vertically stacked columns of blocks. The blocks in each vertical column are keyed together, and a ceramic grid is disposed between each horizontal layer of blocks. Pressure plates cover- the lateral surface of the moderator structure in abutting relationship with the peripheral terminal lengths of the ceramic grids. Tubular springs are disposed between the pressure plates and a rigid external support. The tubular springs have their axes vertically disposed to facilitate passage of coolant gas through the springs and are spaced apart a selected distance such that at sonae preselected point of spring deflection, the sides of the springs will contact adjacent springs thereby causing a large increase in resistance to further spring deflection. (AEC)

  17. REACTOR VIEWING APPARATUS

    DOEpatents

    Monk, G.S.

    1959-01-13

    An optical system is presented that is suitable for viewing objects in a region of relatively high radioactivity, or high neutron activity, such as a neutronic reactor. This optical system will absorb neutrons and gamma rays thereby protecting personnel fronm the harmful biological effects of such penetrating radiations. The optical system is comprised of a viewing tube having a lens at one end, a transparent solid member at the other end and a transparent aqueous liquid completely filling the tube between the ends. The lens is made of a polymerized organic material and the transparent solid member is made of a radiation absorbent material. A shield surrounds the tube betwcen the flanges and is made of a gamma ray absorbing material.

  18. Nuclear reactor control apparatus

    DOEpatents

    Sridhar, Bettadapur N.

    1983-10-25

    Nuclear reactor safety rod release apparatus comprises a ring which carries detents normally positioned in an annular recess in outer side of the rod, the ring being held against the lower end of a drive shaft by magnetic force exerted by a solenoid carried by the drive shaft. When the solenoid is de-energized, the detent-carrying ring drops until the detents contact a cam surface associated with the lower end of the drive shaft, at which point the detents are cammed out of the recess in the safety rod to release the rod from the drive shaft. In preferred embodiments of the invention, an additional latch is provided to release a lower portion of a safety rod under conditions that may interfere with movement of the entire rod.

  19. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Wheelock, C.W.; Baumeister, E.B.

    1961-09-01

    A reactor fuel element utilizing fissionable fuel materials in plate form is described. This fuel element consists of bundles of fuel-bearing plates. The bundles are stacked inside of a tube which forms the shell of the fuel element. The plates each have longitudinal fins running parallel to the direction of coolant flow, and interspersed among and parallel to the fins are ribs which position the plates relative to each other and to the fuel element shell. The plate bundles are held together by thin bands or wires. The ex tended surface increases the heat transfer capabilities of a fuel element by a factor of 3 or more over those of a simple flat plate.

  20. University Reactor Sharing Program

    SciTech Connect

    W.D. Reese

    2004-02-24

    Research projects supported by the program include items such as dating geological material and producing high current super conducting magnets. The funding continues to give small colleges and universities the valuable opportunity to use the NSC for teaching courses in nuclear processes; specifically neutron activation analysis and gamma spectroscopy. The Reactor Sharing Program has supported the construction of a Fast Neutron Flux Irradiator for users at New Mexico Institute of Mining and Technology and the University of Houston. This device has been characterized and has been found to have near optimum neutron fluxes for A39/Ar 40 dating. Institution final reports and publications resulting from the use of these funds are on file at the Nuclear Science Center.

  1. NUCLEAR REACTOR CONTROL SYSTEM

    DOEpatents

    Howard, D.F.; Motta, E.E.

    1961-06-27

    A method for controlling the excess reactivity in a nuclear reactor throughout the core life while maintaining the neutron flux distribution at the desired level is described. The control unit embodies a container having two electrodes of different surface area immersed in an electrolytic solution of a good neutron sbsorbing metal ion such as boron, gadolinium, or cadmium. Initially, the neutron absorber is plated on the larger electrode to control the greater neutron flux of a freshly refueled core. As the fuel burns up, the excess reactivity decreases and the neutron absorber is then plated onto the smaller electrode so that the number of neutrons absorbed also decreases. The excess reactivity in the core may thus be maintained without the introduction of serious perturbations in the neutron flux distributibn.

  2. Staged anaerobic reactor

    SciTech Connect

    Sullivan, R.A.

    1986-02-04

    This patent describes an anaerobic biological reactor for digesting organic substances, particularly high strength industrial and municipal sewage, and producing commercial quality methane. The reactor consists of: a unitary vessel for containing liquid carrying the organic substances to be digested and has a liquid inlet and a liquid outlet; a device for maintaining the liquid in the vessel at a desired level; the capability of dividing the vessel into separate environmentally isolated compartments, adapted to contain a level of liquid having a gas space located above. Each of the compartments is primarily dedicated to the digestion of organic substances by a respectively different microorganism. At least one of the organisms is an acid forming type that digests organic substances and in so doing evolves CO/sub 2/ gas. At least one other of the microorganisms is a type that digests organic substances and in so doing evolves a relatively high quality methane gas; a method for establishing and maintaining the optimum environmental conditions within each of the respective compartments to promote the unique biological activity within that compartment; a way to regulate the pH level; a set of gas operated mixers in each compartment of the vessel for mixing the liquid contained therein to maintain a homogenous mixture; a way for delivering the CO/sub 2/ gas from one compartment to the mixer in the other compartment; a way for flowing and agitating the liquid from the inlet through the environmentally isolated compartments in a predetermined sequence to the outlet; and a method for collecting and removing methane gas evolved in the vessel.

  3. University Reactor Conversion Lessons Learned Workshop for Purdue University Reactor

    SciTech Connect

    Eric C. Woolstenhulme; Dana M. Hewit

    2008-09-01

    The Department of Energy’s Idaho National Laboratory, under its programmatic responsibility for managing the University Research Reactor Conversions, has completed the conversion of the reactor at Purdue University Reactor. With this work completed and in anticipation of other impending conversion projects, the INL convened and engaged the project participants in a structured discussion to capture the lessons learned. The lessons learned process has allowed us to capture gaps, opportunities, and good practices, drawing from the project team’s experiences. These lessons will be used to raise the standard of excellence, effectiveness, and efficiency in all future conversion projects.

  4. Licensed reactor nuclear safety criteria applicable to DOE reactors

    SciTech Connect

    Not Available

    1993-11-01

    This document is a compilation and source list of nuclear safety criteria that the Nuclear Regulatory Commission (NRC) applies to licensed reactors; it can be used by DOE and DOE contractors to identify NRC criteria to be evaluated for application to the DOE reactors under their cognizance. The criteria listed are those that are applied to the areas of nuclear safety addressed in the safety analysis report of a licensed reactor. They are derived from federal regulations, USNRC regulatory guides, Standard Review Plan (SRP) branch technical positions and appendices, and industry codes and standards.

  5. Reactor service life extension program

    SciTech Connect

    Caskey, G.R.; Sindelar, R.L.; Ondrejcin, R.S.; Baumann, E.W.

    1990-01-01

    A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects of helium on mechanical behavior of irradiated stainless steel; improved weld methods for piping and the reactor tanks; and a surveillance program to track irradiation effects on the tank walls.

  6. Reactor service life extension program

    SciTech Connect

    Caskey, G.R.; Sindelar, R.L.; Ondrejcin, R.S.; Baumann, E.W.

    1990-12-31

    A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects of helium on mechanical behavior of irradiated stainless steel; improved weld methods for piping and the reactor tanks; and a surveillance program to track irradiation effects on the tank walls.

  7. Assessment of torsatrons as reactors

    SciTech Connect

    Lyon, J.F. ); Painter, S.L. )

    1992-12-01

    Stellarators have significant operational advantages over tokamaks as ignited steady-state reactors because stellarators have no dangerous disruptions and no need for continuous current drive or power recirculated to the plasma, both easing the first wall, blanket, and shield design; less severe constraints on the plasma parameters and profiles; and better access for maintenance. This study shows that a reactor based on the torsatron configuration (a stellarator variant) could also have up to double the mass utilization efficiency (MUE) and a significantly lower cost of electricity (COE) than a conventional tokamak reactor (ARIES-I) for a range of assumptions. Torsatron reactors can have much smaller coil systems than tokamak reactors because the coils are closer to the plasma and they have a smaller cross section (higher average current density because of the lower magnetic field). The reactor optimization approach and the costing and component models are those used in the current stage of the ARIES-I tokamak reactor study. Typical reactor parameters for a 1-GW(e) Compact Torsatron reactor example are major radius R[sub 0] = 6.6-8.8 m, on-axis magnetic field B[sup 0] = 4.8-7.5 T, B[sub max] (on coils) = 16 T, MUE 140-210 kW(e)/tonne, and COE (in constant 1990 dollars) = 67-79 mill/kW(e)h. The results are relatively sensitive to assumptions on the level of confinement improvement and the blanket thickness under the inboard half of the helical windings but relatively insensitive to other assumptions.

  8. United States Domestic Research Reactor Infrastrucutre TRIGA Reactor Fuel Support

    SciTech Connect

    Douglas Morrell

    2011-03-01

    The United State Domestic Research Reactor Infrastructure Program at the Idaho National Laboratory manages and provides project management, technical, quality engineering, quality inspection and nuclear material support for the United States Department of Energy sponsored University Reactor Fuels Program. This program provides fresh, unirradiated nuclear fuel to Domestic University Research Reactor Facilities and is responsible for the return of the DOE-owned, irradiated nuclear fuel over the life of the program. This presentation will introduce the program management team, the universities supported by the program, the status of the program and focus on the return process of irradiated nuclear fuel for long term storage at DOE managed receipt facilities. It will include lessons learned from research reactor facilities that have successfully shipped spent fuel elements to DOE receipt facilities.

  9. On reactor type comparisons for the next generation of reactors

    SciTech Connect

    Alesso, H.P.; Majumdar, K.C.

    1991-08-22

    In this paper, we present a broad comparison of studies for a selected set of parameters for different nuclear reactor types including the next generation. This serves as an overview of key parameters which provide a semi-quantitative decision basis for selecting nuclear strategies. Out of a number of advanced reactor designs of the LWR type, gas cooled type, and FBR type, currently on the drawing board, the Advanced Light Water Reactors (ALWR) seem to have some edge over other types of the next generation of reactors for the near-term application. This is based on a number of attributes related to the benefit of the vast operating experience with LWRs coupled with an estimated low risk profile, economics of scale, degree of utilization of passive systems, simplification in the plant design and layout, modular fabrication and manufacturing. 32 refs., 1 fig., 3 tabs.

  10. Nuclear reactor downcomer flow deflector

    DOEpatents

    Gilmore, Charles B.; Altman, David A.; Singleton, Norman R.

    2011-02-15

    A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

  11. DENSITY CONTROL IN A REACTOR

    DOEpatents

    Marshall, J. Jr.

    1961-10-24

    A reactor is described in which natural-uranium bodies are located in parallel channels which extend through the graphite mass in a regular lattice. The graphite mass has additional channels that are out of the lattice and contain no uranium. These additional channels decrease in number per unit volume of graphite from the center of the reactor to the exterior and have the effect of reducing the density of the graphite more at the center than at the exterior, thereby spreading neutron activity throughout the reactor. (AEC)

  12. Nuclear reactor I

    DOEpatents

    Ference, Edward W.; Houtman, John L.; Waldby, Robert N.

    1977-01-01

    A nuclear reactor, particularly a liquid-metal breeder reactor whose upper internals include provision for channeling the liquid metal flowing from the core-component assemblies to the outlet plenum in vertical paths in direction generally along the direction of the respective assemblies. The metal is channeled by chimneys, each secured to, and extending from, a grid through whose openings the metal emitted by a plurality of core-component assemblies encompassed by the grid flows. To reduce the stresses resulting from structural interaction, or the transmissive of thermal strains due to large temperature differences in the liquid metal emitted from neighboring core-component assemblies, throughout the chimneys and the other components of the upper internals, the grids and the chimneys are supported from the heat plate and the core barrel by support columns (double portal support) which are secured to the head plate at the top and to a member, which supports the grids and is keyed to the core barrel, at the bottom. In addition to being restrained from lateral flow by the chimneys, the liquid metal is also restrained from flowing laterally by a peripheral seal around the top of the core. This seal limits the flow rate of liquid metal, which may be sharply cooled during a scram, to the outlet nozzles. The chimneys and the grids are formed of a highly-refractory, high corrosion-resistant nickel-chromium-iron alloy which can withstand the stresses produced by temperature differences in the liquid metal. The chimneys are supported by pairs of plates, each pair held together by hollow stubs coaxial with, and encircling, the chimneys. The plates and stubs are a welded structure but, in the interest of economy, are composed of stainless steel which is not weld compatible with the refractory metal. The chimneys and stubs are secured together by shells of another nickel-chromium-iron alloy which is weld compatible with, and is welded to, the stubs and has about the same

  13. Breeder Reactors, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Mitchell, Walter, III; Turner, Stanley E.

    The theory of breeder reactors in relationship to a discussion of fission is presented. Different kinds of reactors are characterized by the cooling fluids used, such as liquid metal, gas, and molten salt. The historical development of breeder reactors over the past twenty-five years includes specific examples of reactors. The location and a brief…

  14. Conceptual design study of JSFR reactor building

    SciTech Connect

    Yamamoto, T.; Katoh, A.; Chikazawa, Y.; Ohya, T.; Iwasaki, M.; Hara, H.; Akiyama, Y.

    2012-07-01

    Japan Sodium-cooled Fast Reactor (JSFR) is planning to adopt the new concepts of reactor building. One is that the steel plate reinforced concrete is adopted for containment vessel and reactor building. The other is the advanced seismic isolation system. This paper describes the detail of new concepts for JSFR reactor building and engineering evaluation of the new concepts. (authors)

  15. Computational Modeling of Multiphase Reactors.

    PubMed

    Joshi, J B; Nandakumar, K

    2015-01-01

    Multiphase reactors are very common in chemical industry, and numerous review articles exist that are focused on types of reactors, such as bubble columns, trickle beds, fluid catalytic beds, etc. Currently, there is a high degree of empiricism in the design process of such reactors owing to the complexity of coupled flow and reaction mechanisms. Hence, we focus on synthesizing recent advances in computational and experimental techniques that will enable future designs of such reactors in a more rational manner by exploring a large design space with high-fidelity models (computational fluid dynamics and computational chemistry models) that are validated with high-fidelity measurements (tomography and other detailed spatial measurements) to provide a high degree of rigor. Understanding the spatial distributions of dispersed phases and their interaction during scale up are key challenges that were traditionally addressed through pilot scale experiments, but now can be addressed through advanced modeling.

  16. METHOD OF OPERATING NUCLEAR REACTORS

    DOEpatents

    Untermyer, S.

    1958-10-14

    A method is presented for obtaining enhanced utilization of natural uranium in heavy water moderated nuclear reactors by charging the reactor with an equal number of fuel elements formed of natural uranium and of fuel elements formed of uranium depleted in U/sup 235/ to the extent that the combination will just support a chain reaction. The reactor is operated until the rate of burnup of plutonium equals its rate of production, the fuel elements are processed to recover plutonium, the depleted uranium is discarded, and the remaining uranium is formed into fuel elements. These fuel elements are charged into a reactor along with an equal number of fuel elements formed of uranium depleted in U/sup 235/ to the extent that the combination will just support a chain reaction, and reuse of the uranium is continued as aforesaid until it wlll no longer support a chain reaction when combined with an equal quantity of natural uranium.

  17. University Reactor Matching Grants Program

    SciTech Connect

    John Valentine; Farzad Rahnema; Said Abdel-Khalik

    2003-02-14

    During the 2002 Fiscal year, funds from the DOE matching grant program, along with matching funds from the industrial sponsors, have been used to support research in the area of thermal-hydraulics. Both experimental and numerical research projects have been performed. Experimental research focused on two areas: (1) Identification of the root cause mechanism for axial offset anomaly in pressurized water reactors under prototypical reactor conditions, and (2) Fluid dynamic aspects of thin liquid film protection schemes for inertial fusion reactor chambers. Numerical research focused on two areas: (1) Multi-fluid modeling of both two-phase and two-component flows for steam conditioning and mist cooling applications, and (2) Modeling of bounded Rayleigh-Taylor instability with interfacial mass transfer and fluid injection through a porous wall simulating the ''wetted wall'' protection scheme in inertial fusion reactor chambers. Details of activities in these areas are given.

  18. Reactor operation environmental information document

    SciTech Connect

    Bauer, L.R.; Hayes, D.W.; Hunter, C.H.; Marter, W.L.; Moyer, R.A.

    1989-12-01

    This volume is a reactor operation environmental information document for the Savannah River Plant. Topics include meteorology, surface hydrology, transport, environmental impacts, and radiation effects. 48 figs., 56 tabs. (KD)

  19. Nuclear Reactors and Technology; (USA)

    SciTech Connect

    Cason, D.L.; Hicks, S.C.

    1991-01-01

    Nuclear Reactors and Technology (NRT) announces on a monthly basis the current worldwide information available from the open literature on nuclear reactors and technology, including all aspects of power reactors, components and accessories, fuel elements, control systems, and materials. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past month. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Energy Technology Data Exchange or government-to-government agreements. The digests in NRT and other citations to information on nuclear reactors back to 1948 are available for online searching and retrieval on EDB and Nuclear Science Abstracts (NSA) database. Current information, added daily to EDB, is available to DOE and its contractors through the DOE integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs.

  20. Combustion synthesis continuous flow reactor

    DOEpatents

    Maupin, G.D.; Chick, L.A.; Kurosky, R.P.

    1998-01-06

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor. 10 figs.

  1. CALANDRIA TYPE SODIUM GRAPHITE REACTOR

    DOEpatents

    Peterson, R.M.; Mahlmeister, J.E.; Vaughn, N.E.; Sanders, W.J.; Williams, A.C.

    1964-02-11

    A sodium graphite power reactor in which the unclad graphite moderator and fuel elements are contained within a core tank is described. The core tank is submersed in sodium within the reactor vessel. Extending longitudinally through the core thnk are process tubes with fuel elements positioned therein. A bellows sealing means allows axial expansion and construction of the tubes. Within the core tank, a leakage plenum is located below the graphite, and above the graphite is a gas space. A vent line regulates the gas pressure in the space, and another line removes sodium from the plenum. The sodium coolant flows from the lower reactor vessel through the annular space between the fuel elements and process tubes and out into the reactor vessel space above the core tank. From there, the heated coolant is drawn off through an outlet line and sent to the heat exchange. (AEC)

  2. Advanced Catalytic Hydrogenation Retrofit Reactor

    SciTech Connect

    Reinaldo M. Machado

    2002-08-15

    Industrial hydrogenation is often performed using a slurry catalyst in large stirred-tank reactors. These systems are inherently problematic in a number of areas, including industrial hygiene, process safety, environmental contamination, waste production, process operability and productivity. This program proposed the development of a practical replacement for the slurry catalysts using a novel fixed-bed monolith catalyst reactor, which could be retrofitted onto an existing stirred-tank reactor and would mitigate many of the minitations and problems associated with slurry catalysts. The full retrofit monolith system, consisting of a recirculation pump, gas/liquid ejector and monolith catalyst, is described as a monolith loop reactor or MLR. The MLR technology can reduce waste and increase raw material efficiency, which reduces the overall energy required to produce specialty and fine chemicals.

  3. STEAM GENERATOR FOR NUCLEAR REACTOR

    DOEpatents

    Kinyon, B.W.; Whitman, G.D.

    1963-07-16

    The steam generator described for use in reactor powergenerating systems employs a series of concentric tubes providing annular passage of steam and water and includes a unique arrangement for separating the steam from the water. (AEC)

  4. Unique features of space reactors

    SciTech Connect

    Buden, D.

    1990-01-01

    Space reactors are designed to meet a unique set of requirements; they must be sufficiently compact to be launched in a rocket to their operational location, operate for many years without maintenance and servicing, operate in extreme environments, and reject heat by radiation to space. To meet these restrictions, operating temperatures are much greater than in terrestrial power plants, and the reactors tend to have a fast neutron spectrum. Currently, a new generation of space reactor power plants is being developed. The major effort is in the SP-100 program, where the power plant is being designed for seven years of full power, and no maintenance operation at a reactor outlet operating temperature of 1350 K. 8 refs., 3 figs., 1 tab.

  5. FUEL ELEMENTS FOR NEUTRONIC REACTORS

    DOEpatents

    Foote, F.G.; Jette, E.R.

    1963-05-01

    A fuel element for a nuclear reactor is described that consists of a jacket containing a unitary core of fissionable material and a filling of a metal of the group consisting of sodium and sodium-potassium alloys. (AEC)

  6. Reactor core isolation cooling system

    DOEpatents

    Cooke, F.E.

    1992-12-08

    A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom. 1 figure.

  7. Reactor core isolation cooling system

    DOEpatents

    Cooke, Franklin E.

    1992-01-01

    A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom.

  8. Overview of fusion reactor safety

    NASA Astrophysics Data System (ADS)

    Cohen, S.; Crocker, J. G.

    Use of deuterium-tritium fusion reactors requires examination of several major safety and environmental issues: (1) tritium inventory control; (2) neutron activation of structural materials, fluid streams and reactor hall environment; (3) release of radioactivity from energy sources including lithium spill reactions, superconducting magnet stored energy release, and plasma disruptions; (4) high magnetic and electromagnetic fields associated with fusion reactor superconducting magnets and radio frequency heating devices; and (5) handling and disposal of radioactive waste. Early recognition of potential safety problems with fusion reactors provides the opportunity for improvement in design and materials to eliminate or greatly reduce these problems. With an early start in this endeavor, fusion should be among the lower risk technologies for generation of commercial electrical power.

  9. Computational Modeling of Multiphase Reactors.

    PubMed

    Joshi, J B; Nandakumar, K

    2015-01-01

    Multiphase reactors are very common in chemical industry, and numerous review articles exist that are focused on types of reactors, such as bubble columns, trickle beds, fluid catalytic beds, etc. Currently, there is a high degree of empiricism in the design process of such reactors owing to the complexity of coupled flow and reaction mechanisms. Hence, we focus on synthesizing recent advances in computational and experimental techniques that will enable future designs of such reactors in a more rational manner by exploring a large design space with high-fidelity models (computational fluid dynamics and computational chemistry models) that are validated with high-fidelity measurements (tomography and other detailed spatial measurements) to provide a high degree of rigor. Understanding the spatial distributions of dispersed phases and their interaction during scale up are key challenges that were traditionally addressed through pilot scale experiments, but now can be addressed through advanced modeling. PMID:26134737

  10. Combustion synthesis continuous flow reactor

    DOEpatents

    Maupin, Gary D.; Chick, Lawrence A.; Kurosky, Randal P.

    1998-01-01

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor.

  11. Reactor vessel seal service fixture

    DOEpatents

    Ritz, W.C.

    1975-12-01

    An apparatus for the preparation of exposed sealing surfaces along the open rim of a nuclear reactor vessel comprised of a motorized mechanism for traveling along the rim and simultaneously brushing the exposed surfaces is described.

  12. Solid State Reactor Final Report

    SciTech Connect

    Mays, G.T.

    2004-03-10

    The Solid State Reactor (SSR) is an advanced reactor concept designed to take advantage of Oak Ridge National Laboratory's (ORNL's) recently developed graphite foam that has enhanced heat transfer characteristics and excellent high-temperature mechanical properties, to provide an inherently safe, self-regulated, source of heat for power and other potential applications. This work was funded by the U.S. Department of Energy's Nuclear Energy Research Initiative (NERI) program (Project No. 99-064) from August 1999 through September 30, 2002. The initial concept of utilizing the graphite foam as a basis for developing an advanced reactor concept envisioned that a suite of reactor configurations and power levels could be developed for several different applications. The initial focus was looking at the reactor as a heat source that was scalable, independent of any heat removal/power conversion process. These applications might include conventional power generation, isotope production and destruction (actinides), and hydrogen production. Having conducted the initial research on the graphite foam and having performed the scoping parametric analyses from neutronics and thermal-hydraulic perspectives, it was necessary to focus on a particular application that would (1) demonstrate the viability of the overall concept and (2) require a reasonably structured design analysis process that would synthesize those important parameters that influence the concept the most as part of a feasible, working reactor system. Thus, the application targeted for this concept was supplying power for remote/harsh environments and a design that was easily deployable, simplistic from an operational standpoint, and utilized the new graphite foam. Specifically, a 500-kW(t) reactor concept was pursued that is naturally load following, inherently safe, optimized via neutronic studies to achieve near-zero reactivity change with burnup, and proliferation resistant. These four major areas of research

  13. Reactor pressure vessel nozzle

    DOEpatents

    Challberg, Roy C.; Upton, Hubert A.

    1994-01-01

    A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat. In the backflow direction from the second port to the first port, the conical channel is a converging channel and with the abrupt increase in flow area from the throat to the first port collectively increase resistance to flow therethrough.

  14. Reactor pressure vessel nozzle

    DOEpatents

    Challberg, R.C.; Upton, H.A.

    1994-10-04

    A nozzle for joining a pool of water to a nuclear reactor pressure vessel includes a tubular body having a proximal end joinable to the pressure vessel and a distal end joinable in flow communication with the pool. The body includes a flow passage therethrough having in serial flow communication a first port at the distal end, a throat spaced axially from the first port, a conical channel extending axially from the throat, and a second port at the proximal end which is joinable in flow communication with the pressure vessel. The inner diameter of the flow passage decreases from the first port to the throat and then increases along the conical channel to the second port. In this way, the conical channel acts as a diverging channel or diffuser in the forward flow direction from the first port to the second port for recovering pressure due to the flow restriction provided by the throat. In the backflow direction from the second port to the first port, the conical channel is a converging channel and with the abrupt increase in flow area from the throat to the first port collectively increase resistance to flow therethrough. 2 figs.

  15. Reactor Simulator Testing Overview

    NASA Technical Reports Server (NTRS)

    Schoenfeld, Michael P.

    2013-01-01

    Test Objectives Summary: a) Verify operation of the core simulator, the instrumentation & control system, and the ground support gas and vacuum test equipment. b) Examine cooling & heat regeneration performance of the cold trap purification. c) Test the ALIP pump at voltages beyond 120V to see if the targeted mass flow rate of 1.75 kg/s can be obtained in the RxSim. Testing Highlights: a) Gas and vacuum ground support test equipment performed effectively for operations (NaK fill, loop pressurization, and NaK drain). b) Instrumentation & Control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings and ramped within prescribed constraints. It effectively interacted with reactor simulator control model and defaulted back to temperature control mode if the transient fluctuations didn't dampen. c) Cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the minimum temperature indicating the design provided some heat regeneration. d) ALIP produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  16. Reactor shroud joint

    DOEpatents

    Ballas, Gary J.; Fife, Alex Blair; Ganz, Israel

    1998-01-01

    A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings in the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges.

  17. Reactor shroud joint

    DOEpatents

    Ballas, G.J.; Fife, A.B.; Ganz, I.

    1998-04-07

    A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings in the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges. 4 figs.

  18. Solar solids reactor

    DOEpatents

    Yudow, B.D.

    1986-02-24

    A solar powered kiln is provided, that is of relatively simple design and which efficiently uses solar energy. The kiln or solids reactor includes a stationary chamber with a rearward end which receives solid material to be reacted and a forward end through which reacted material is disposed of, and a screw conveyor extending along the bottom of the chamber for slowly advancing the material between the chamber ends. Concentrated solar energy is directed to an aperture at the forward end of the chamber to heat the solid material moving along the bottom of the chamber. The solar energy can be reflected from a mirror facing at an upward incline, through the aperture and against a heat-absorbing material near the top of the chamber, which moves towards the rear of the chamber to distribute heat throughout the chamber. Pumps at the forward and rearward ends of the chamber pump heated sweep gas through the length of the chamber, while minimizing the flow of gas through an open aperture through which concentrated sunlight is received.

  19. Solar solids reactor

    DOEpatents

    Yudow, Bernard D.

    1987-01-01

    A solar powered kiln is provided, that is of relatively simple design and which efficiently uses solar energy. The kiln or solids reactor includes a stationary chamber with a rearward end which receives solid material to be reacted and a forward end through which reacted material is disposed of, and a screw conveyor extending along the bottom of the chamber for slowly advancing the material between the chamber ends. Concentrated solar energy is directed to an aperture at the forward end of the chamber to heat the solid material moving along the bottom of the chamber. The solar energy can be reflected from a mirror facing at an upward incline, through the aperture and against a heat-absorbing material near the top of the chamber, which moves towards the rear of the chamber to distribute heat throughout the chamber. Pumps at the forward and rearward ends of the chamber pump heated sweep gas through the length of the chamber, while minimizing the flow of gas through an open aperture through which concentrated sunlight is received.

  20. Reactor Simulator Testing

    NASA Technical Reports Server (NTRS)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise J.

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz.

  1. Reactor antineutrino experiments

    NASA Astrophysics Data System (ADS)

    Lu, Haoqi

    2014-09-01

    Neutrinos are elementary particles in the standard model of particle physics. There are three flavors of neutrinos that oscillate among themselves. Their oscillation can be described by a 3×3 unitary matrix, containing three mixing angles θ12, θ23, θ13, and one CP phase. Both θ12 and θ23 are known from previous experiments. θ13 was unknown just two years ago. The Daya Bay experiment gave the first definitive nonzero value in 2012. An improved measurement of the oscillation amplitude sin 22(θ 13) = 0.090+0.008-0.009 and the first direct measurement of the \\bar ν e mass-squared difference \\vertΔ m2ee\\vert\\big (2.59+0.19-0.20\\big )×10-3 eV2 were obtained recently. The large value of θ13 boosts the next generation of reactor antineutrino experiments designed to determine the neutrino mass hierarchy, such as JUNO and RENO-50.

  2. Novel Catalytic Membrane Reactors

    SciTech Connect

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  3. REACTOR CONTROL MECHANISM

    DOEpatents

    Lane, J.A.; Engberg, R.E.; Welch, J.M.

    1959-05-12

    A quick-releasing mechanism is described which may be used to rapidiy drop a device supported from beneath during normal use, such as a safety rod in a nuclear reactor. In accordance with this invention an electrical control signal, such as may be provided by radiation detection or other alarm condition sensing devices, is delivered to an electromagnetic solenoid, the armature of which is coupled to an actuating mechanism. The solenoid is energized when the mechanism is in its upper or cocked position. In such position, the mechanism engages a plurality of retaining balls, forcing them outward into engagement with a shoulder or recess in a corresponding section of a tubular extension on the upheld device. When the control signal to the solenoid suddenly ceases, the armature drops out, allowing the actuating mechanism to move slightly but rapidly under the force of a compressed spring. The weight of the device will urge the balls inward against a beveled portion of the actuating mechanism and away from the engaging section on the tubular extension, thus allowing the upheld device to fall freely under the influence of gravity.

  4. Automatic safety rod for reactors

    DOEpatents

    Germer, John H.

    1988-01-01

    An automatic safety rod for a nuclear reactor containing neutron absorbing material and designed to be inserted into a reactor core after a loss-of-core flow. Actuation is based upon either a sudden decrease in core pressure drop or the pressure drop decreases below a predetermined minimum value. The automatic control rod includes a pressure regulating device whereby a controlled decrease in operating pressure due to reduced coolant flow does not cause the rod to drop into the core.

  5. Fast quench reactor and method

    DOEpatents

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.

    2002-01-01

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a restrictive convergent-divergent nozzle at its outlet end. Reactants are injected into the reactor chamber. The resulting heated gaseous stream is then rapidly cooled by passage through the nozzle. This "freezes" the desired end product(s) in the heated equilibrium reaction stage.

  6. Fast quench reactor and method

    DOEpatents

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.

    2002-09-24

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a restrictive convergent-divergent nozzle at its outlet end. Reactants are injected into the reactor chamber. The resulting heated gaseous stream is then rapidly cooled by passage through the nozzle. This "freezes" the desired end product(s) in the heated equilibrium reaction stage.

  7. Fast quench reactor and method

    DOEpatents

    Detering, Brent A.; Donaldson, Alan D.; Fincke, James R.; Kong, Peter C.

    1998-01-01

    A fast quench reaction includes a reactor chamber having a high temperature heating means such as a plasma torch at its inlet and a restrictive convergent-divergent nozzle at its outlet end. Reactants are injected into the reactor chamber. The resulting heated gaseous stream is then rapidly cooled by passage through the nozzle. This "freezes" the desired end product(s) in the heated equilibrium reaction stage.

  8. NCSU PULSTAR Reactor instrumentation upgrade

    SciTech Connect

    Perez, P.B.; Bilyj, S.J.

    1993-08-12

    The Nuclear Reactor Program at North Carolina State University initiated an upgrade program at the NCSU PULSTAR Reactor in 1990. Twenty-year-old instrumentation is currently undergoing replacement with solid-state and current technology equipment. The financial assistance from the United States Department of Energy has been the primary source of support. This interim report provides the status of the first two phases of the upgrade program.

  9. [Reactor safety and human failure].

    PubMed

    Smidt, D

    1979-12-01

    Reactor safety is given by the reliable solution of 3 tasks: on-time shutdown, continuous decay-heat removal, safe containment. After describing the general strategy of their solution even under upset conditions the most important engineered safeguards of pressurized water reactors are summarized. The important problem of human failure is discussed in some more detail. For the example Harrisburg some difficulties, but also some technical countermeasures are illustrated. PMID:537639

  10. Reactor Application for Coaching Newbies

    SciTech Connect

    2015-06-17

    RACCOON is a Moose based reactor physics application designed to engage undergraduate and first-year graduate students. The code contains capabilities to solve the multi group Neutron Diffusion equation in eigenvalue and fixed source form and will soon have a provision to provide simple thermal feedback. These capabilities are sufficient to solve example problems found in Duderstadt & Hamilton (the typical textbook of senior level reactor physics classes). RACCOON does not contain any advanced capabilities as found in YAK.

  11. Biological sludge stabilization reactor evaluations

    SciTech Connect

    Corbitt, R.A.; Bowen, P.T.; Smith, P.E.

    1998-07-01

    Anaerobic digestion was chosen as the means to stabilize primary and thickened waste activated sludge for a 0.88 m{sup 3}/s (20 mgd) advanced wastewater reclamation facility. Two stage digestion was proposed to produce Class B sludge. Reactor shape was an important variable in design of the first stage digestion. Evaluation of conventional and egg shaped anaerobic digesters was performed. Based on the economic and non-economic criteria analysis, egg shaped reactors were selected.

  12. MOLTEN FLUORIDE NUCLEAR REACTOR FUEL

    DOEpatents

    Barton, C.J.; Grimes, W.R.

    1960-01-01

    Molten-salt reactor fuel compositions consisting of mixtures of fluoride salts are reported. In its broadest form, the composition contains an alkali fluoride such as sodium fluoride, zirconium tetrafluoride, and a uranium fluoride, the latter being the tetrafluoride or trifluoride or a mixture of the two. An outstanding property of these fuel compositions is a high coeffieient of thermal expansion which provides a negative temperature coefficient of reactivity in reactors in which they are used.

  13. Microchannel Reactors for ISRU Applications

    NASA Astrophysics Data System (ADS)

    Carranza, Susana; Makel, Darby B.; Blizman, Brandon; Ward, Benjamin J.

    2005-02-01

    Affordable planning and execution of prolonged manned space missions depend upon the utilization of local resources and the waste products which are formed in manned spacecraft and surface bases. Successful in-situ resources utilization (ISRU) will require component technologies which provide optimal size, weight, volume, and power efficiency. Microchannel reactors enable the efficient chemical processing of in situ resources. The reactors can be designed for the processes that generate the most benefit for each mission. For instance, propellants (methane) can be produced from carbon dioxide from the Mars atmosphere using the Sabatier reaction and ethylene can be produced from the partial oxidation of methane. A system that synthesizes ethylene could be the precursor for systems to synthesize ethanol and polyethylene. Ethanol can be used as a nutrient for Astrobiology experiments, as well as the production of nutrients for human crew (e.g. sugars). Polyethylene can be used in the construction of habitats, tools, and replacement parts. This paper will present recent developments in miniature chemical reactors using advanced Micro Electro Mechanical Systems (MEMS) and microchannel technology to support ISRU of Mars and lunar missions. Among other applications, the technology has been demonstrated for the Sabatier process and for the partial oxidation of methane. Microchannel reactors were developed based on ceramic substrates as well as metal substrates. In both types of reactors, multiple layers coated with catalytic material are bonded, forming a monolithic structure. Such reactors are readily scalable with the incorporation of extra layers. In addition, this reactor structure minimizes pressure drop and catalyst settling, which are common problems in conventional packed bed reactors.

  14. The International Reactor Dosimetry File.

    2008-08-07

    Version 01 The International Reactor Dosimetry File (IRDF-2002) contains recommended neutron cross-section data to be used for reactor neutron dosimetry by foil activation and subsequent neutron spectrum unfolding. It also contains selected recom�mended values for radiation damage cross-sections and benchmark neutron spectra. Two related programs available from NEADB and RSICC are: SPECTER-ANL (PSR-263) & STAY’SL (PSR-113).

  15. Evaluation of Torsatrons as reactors

    SciTech Connect

    Lyon, J.F.; Gulec, K.; Miller, R.L.; El-Guebaly, L.

    1994-03-01

    Stellarators have significant operational advantages over tokamaks as ignited steady-state reactors. This scoping study, which uses an integrated cost-minimization code that incorporates costing and reactor component models self-consistently with a 1-D energy transport calculation, shows that a torsatron reactor could also be economically competitive with a tokamak reactor. The projected cost of electricity (COE) estimated using the Advanced Reactor Innovation and Evaluation Studies (ARIES) costing algorithms is 65.6 mill/kW(e)h in constant 1992 dollars for a reference 1-GW(e) Compact Torsatron reactor case. The COE is relatively insensitive (<10% variation) over a wide range of assumptions, including variations in the maximum field allowed on the coils, the coil elongation, the shape of the density profile, the beta limit, the confinement multiplier, and the presence of a large loss region for alpha particles. The largest variations in the COE occur for variations in the electrical power output demanded and the plasma-coil separation ratio.

  16. Propellant actuated nuclear reactor steam depressurization valve

    DOEpatents

    Ehrke, Alan C.; Knepp, John B.; Skoda, George I.

    1992-01-01

    A nuclear fission reactor combined with a propellant actuated depressurization and/or water injection valve is disclosed. The depressurization valve releases pressure from a water cooled, steam producing nuclear reactor when required to insure the safety of the reactor. Depressurization of the reactor pressure vessel enables gravity feeding of supplementary coolant water through the water injection valve to the reactor pressure vessel to prevent damage to the fuel core.

  17. Reactor operations: Brookhaven Medical Research Reactor, Brookhaven High Flux Beam Reactor. Informal report, July 1995

    SciTech Connect

    1995-07-01

    Part one of this report gives the operating history for the Brookhaven Medical Research Reactor for the month of July. Also included are the BMRR technical safety surveillance requirements record and the summary of BMRR irradiations for the month. Part two gives the operating histories for the Brookhaven High Flux Beam Reactor and the Cold Neutron Source Facility for the month of July. Also included are the HFBR technical safety surveillance requirements record and the summary of HFBR irradiations for the month.

  18. Reactor operations: Brookhaven Medical Research Reactor, Brookhaven High Flux Beam Reactor. Informal report, June 1995

    SciTech Connect

    1995-06-01

    Part one of this report gives the operating history of the Brookhaven Medical Research Reactor for the month of June. Also included are the BMRR technical safety surveillance requirements record and the summary of BMRR irradiations for the month. Part two gives the operating histories of the Brookhaven High Flux Beam Reactor and the Cold Neutron Facility at HFBR for June. Also included are the HFBR technical safety surveillance requirements record and the summary of HFBR irradiations for the month.

  19. SPRAY CALCINATION REACTOR

    DOEpatents

    Johnson, B.M.

    1963-08-20

    A spray calcination reactor for calcining reprocessin- g waste solutions is described. Coaxial within the outer shell of the reactor is a shorter inner shell having heated walls and with open regions above and below. When the solution is sprayed into the irner shell droplets are entrained by a current of gas that moves downwardly within the inner shell and upwardly between it and the outer shell, and while thus being circulated the droplets are calcined to solids, whlch drop to the bottom without being deposited on the walls. (AEC) H03 H0233412 The average molecular weights of four diallyl phthalate polymer samples extruded from the experimental rheometer were redetermined using the vapor phase osmometer. An amine curing agent is required for obtaining suitable silver- filled epoxy-bonded conductive adhesives. When the curing agent was modified with a 47% polyurethane resin, its effectiveness was hampered. Neither silver nor nickel filler impart a high electrical conductivity to Adiprenebased adhesives. Silver filler was found to perform well in Dow-Corning A-4000 adhesive. Two cascaded hot-wire columns are being used to remove heavy gaseous impurities from methane. This purified gas is being enriched in the concentric tube unit to approximately 20% carbon-13. Studies to count low-level krypton-85 in xenon are continuing. The parameters of the counting technique are being determined. The bismuth isotopes produced in bismuth irradiated for polonium production are being determined. Preliminary data indicate the presence of bismuth207 and bismuth-210m. The light bismuth isotopes are probably produced by (n,xn) reactions bismuth-209. The separation of uranium-234 from plutonium-238 solutions was demonstrated. The bulk of the plutonium is removed by anion exchange, and the remainder is extracted from the uranium by solvent extraction techniques. About 99% of the plutonium can be removed in each thenoyltrifluoroacetone extraction. The viscosity, liquid density, and

  20. Reactor Simulator Testing

    NASA Technical Reports Server (NTRS)

    Schoenfeld, Michael P.; Webster, Kenny L.; Pearson, Boise Jon

    2013-01-01

    As part of the Nuclear Systems Office Fission Surface Power Technology Demonstration Unit (TDU) project, a reactor simulator test loop (RxSim) was design & built to perform integrated testing of the TDU components. In particular, the objectives of RxSim testing was to verify the operation of the core simulator, the instrumentation and control system, and the ground support gas and vacuum test equipment. In addition, it was decided to include a thermal test of a cold trap purification design and a pump performance test at pump voltages up to 150 V since the targeted mass flow rate of 1.75 kg/s was not obtained in the RxSim at the originally constrained voltage of 120 V. This paper summarizes RxSim testing. The gas and vacuum ground support test equipment performed effectively in NaK fill, loop pressurization, and NaK drain operations. The instrumentation and control system effectively controlled loop temperature and flow rates or pump voltage to targeted settings. The cold trap design was able to obtain the targeted cold temperature of 480 K. An outlet temperature of 636 K was obtained which was lower than the predicted 750 K but 156 K higher than the cold temperature indicating the design provided some heat regeneration. The annular linear induction pump (ALIP) tested was able to produce a maximum flow rate of 1.53 kg/s at 800 K when operated at 150 V and 53 Hz. Keywords: fission, space power, nuclear, liquid metal, NaK.