Sample records for white sands complex

  1. Integration of the White Sands Complex into a Wide Area Network

    NASA Technical Reports Server (NTRS)

    Boucher, Phillip Larry; Horan, Sheila, B.

    1996-01-01

    The NASA White Sands Complex (WSC) satellite communications facility consists of two main ground stations, an auxiliary ground station, a technical support facility, and a power plant building located on White Sands Missile Range. When constructed, terrestrial communication access to these facilities was limited to copper telephone circuits. There was no local or wide area communications network capability. This project incorporated a baseband local area network (LAN) topology at WSC and connected it to NASA's wide area network using the Program Support Communications Network-Internet (PSCN-I). A campus-style LAN is configured in conformance with the International Standards Organization (ISO) Open Systems Interconnect (ISO) model. Ethernet provides the physical and data link layers. Transmission Control Protocol and Internet Protocol (TCP/IP) are used for the network and transport layers. The session, presentation, and application layers employ commercial software packages. Copper-based Ethernet collision domains are constructed in each of the primary facilities and these are interconnected by routers over optical fiber links. The network and each of its collision domains are shown to meet IEEE technical configuration guidelines. The optical fiber links are analyzed for the optical power budget and bandwidth allocation and are found to provide sufficient margin for this application. Personal computers and work stations attached to the LAN communicate with and apply a wide variety of local and remote administrative software tools. The Internet connection provides wide area network (WAN) electronic access to other NASA centers and the world wide web (WWW). The WSC network reduces and simplifies the administrative workload while providing enhanced and advanced inter-communications capabilities among White Sands Complex departments and with other NASA centers.

  2. Numerical study of turbulent flow over complex aeolian dune fields: the White Sands National Monument.

    PubMed

    Anderson, William; Chamecki, Marcelo

    2014-01-01

    The structure and dynamics of fully developed turbulent flows responding to aeolian dune fields are studied using large-eddy simulation with an immersed boundary method. An aspect of particular importance in these flows is the downwind migration of coherent motions associated with Kelvin-Helmholtz instabilities that originate at the dune crests. These instabilities are responsible for enhanced downward transport of high-momentum fluid via the so-called turbulent sweep mechanism. However, the presence of such structures and their role in determining the bulk characteristics of fully developed dune field sublayer aerodynamics have received relatively limited attention. Moreover, many existing studies address mostly symmetric or mildly asymmetric dune forms. The White Sands National Monument is a field of aeolian gypsum sand dunes located in the Tularosa Basin in southern New Mexico. Aeolian processes at the site result in a complex, anisotropic dune field. In the dune field sublayer, the flow statistics resemble a mixing layer: At approximately the dune crest height, vertical profiles of streamwise velocity exhibit an inflection and turbulent Reynolds stresses are maximum; below this, the streamwise and vertical velocity fluctuations are positively and negatively skewed, respectively. We evaluate the spatial structure of Kelvin-Helmholtz instabilities present in the dune field sublayer (shear length L(s) and vortex spacing ?(x)) and show that ?(x)=m(dune)L(s), where m(dune)?7.2 in the different sections considered (for turbulent mixing layers, 7

  3. A numerical study of turbulent flow over complex aeolian dune fields: the White Sands National Monument

    NASA Astrophysics Data System (ADS)

    Anderson, William; Chamecki, Marcelo; Kocurek, Gary; Mohrig, David

    2013-11-01

    The structure and dynamics of fully-developed turbulent flows responding to aeolian dune fields are studied using large-eddy simulation with an immersed boundary method. An aspect of particular importance in these flows is the downwind migration of coherent motions associated with Kelvin-Helmholtz instabilities which originate at the dune crests. These instabilities are responsible for enhanced downward transport of high momentum fluid via the so-called turbulent sweep mechanism. However, the presence of such structures and their role in determining the bulk characteristics of fully developed dune field sublayer aerodynamics has received relatively limited attention. Moreover, many existing studies address mostly symmetric or mildly asymmetric dune forms. The White Sands National Monument is a field of aeolian gypsum sand dunes in southern New Mexico. In the dune field sublayer, the flow statistics resemble a mixing layer: at approximately the dune crest height, vertical profiles of streamwise velocity exhibit an inflection and turbulent Reynolds stresses are maximum; below this, the streamwise and vertical velocity fluctuations are positively and negatively skewed, respectively. We evaluate the spatial structure of Kelvin-Helmholtz instabilities present in the dune field sublayer - shear length, Ls, and vortex spacing, Lambda_x - and show that Ls = m Lambda_x, where m is approximately 8 in the different sections considered.

  4. White Sands, Carrizozo Lava Beds, NM

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A truly remarkable view of White Sands and the nearby Carrizozo Lava Beds in southeast NM (33.5N, 106.5W). White Sands, site of the WW II atomic bomb development and testing facility and later post war nuclear weapons testing that can still be seen in the cleared circular patterns on the ground.

  5. Ecological release in White Sands lizards

    PubMed Central

    Roches, S Des; Robertson, J M; Harmon, L J; Rosenblum, E B

    2011-01-01

    Ecological opportunity is any change that allows populations to escape selection from competition and predation. After encountering ecological opportunity, populations may experience ecological release: enlarged population size, broadened resource use, and/or increased morphological variation. We identified ecological opportunity and tested for ecological release in three lizard colonists of White Sands, New Mexico (Sceloporus undulatus, Holbrookia maculata, and Aspidoscelis inornata). First, we provide evidence for ecological opportunity by demonstrating reduced species richness and abundance of potential competitors and predators at White Sands relative to nearby dark soils habitats. Second, we characterize ecological release at White Sands by demonstrating density compensation in the three White Sands lizard species and expanded resource use in White Sands S. undulatus. Contrary to predictions from ecological release models, we observed directional trait change but not increased trait variation in S. undulatus. Our results suggest that ecological opportunity and ecological release can be identified in natural populations, especially those that have recently colonized isolated ecosystems. PMID:22393523

  6. NASA White Sands Test Facility Remote Hypervelocity Test Laboratory - Duration: 7 minutes, 52 seconds.

    NASA Video Gallery

    Tour the NASA White Sands Test Facility's Remote Hypervelocity Test Laboratory in Las Cruces, New Mexico. To learn more about White Sands Test Facility, go to http://www.nasa.gov/centers/wstf/home/...

  7. Fiber optic cable vulnerability test, White Sands, New Mexico

    Microsoft Academic Search

    S. F. Large; G. W. Styskal

    1982-01-01

    Tests were performed at the White Sands Missile Range, New Mexico, to evaluate the response of buried fiber optic cables to the accelerations and stresses developed by an explosive charge. During these tests, observations were made of cable transmissivity characteristics that might be affected by these forces. Transmission bit error rate (BER) measurements were made to determine cable performance changes.

  8. NASA Johnson Space Center: White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Aggarwal, Pravin; Kowalski, Robert R.

    2011-01-01

    This slide presentation reviews the testing facilities and laboratories available at the White Sands Test Facility (WSTF). The mission of WSTF is to provide the expertise and infrastructure to test and evaluate spacecraft materials, components and propulsion systems that enable the safe exploration and use of space. There are nine rocket test stands in two major test areas, six altitude test stands, three ambient test stands,

  9. 3. GENERAL VIEW OF COMPLEX LOOKING SOUTH, SAND DRAINING & ...

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

    3. GENERAL VIEW OF COMPLEX LOOKING SOUTH, SAND DRAINING & DRYING BUILDING (right) AND SAND-SORTING BUILDING (left) - Mill "C" Complex, South of Dee Bennet Road, near Illinois River, Ottawa, La Salle County, IL

  10. 1. GENERAL VIEW OF COMPLEX FROM SANDPIT LOOKING NORTHEAST, SAND ...

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

    1. GENERAL VIEW OF COMPLEX FROM SANDPIT LOOKING NORTHEAST, SAND DRAINING & DRYING BUILDING (left) AND SAND-SORTING BUILDING (right) - Mill "C" Complex, South of Dee Bennet Road, near Illinois River, Ottawa, La Salle County, IL

  11. 2. GENERAL VIEW OF COMPLEX FROM SANDPIT LOOKING NORTHEAST, SAND ...

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

    2. GENERAL VIEW OF COMPLEX FROM SANDPIT LOOKING NORTHEAST, SAND DRAINING & DRYING BUILDING (left) AND SAND-SORTING BUILDING (right) - Mill "C" Complex, South of Dee Bennet Road, near Illinois River, Ottawa, La Salle County, IL

  12. Two-Phase Abrasion in Eolian Transport of Gypsum Sand, White Sands NM

    NASA Astrophysics Data System (ADS)

    Shaw, S.; Jerolmack, D. J.; Miller, K. L.

    2014-12-01

    Downstream rounding of grains is consistently observed in natural sediment transport settings. A recent theory put forth by Domokos et al. (2014) attributes particle rounding and size reduction to a geometric curvature-driven abrasion process. This process occurs in two phases, in which irregularly shaped or angular particles round to convex shapes with negligible change in axis dimension, then slowly reduce in particle diameter. Miller et al (in review) establish the existence of two-phase abrasion in the natural setting of a fluvial gravel stream. This study examines field samples from White Sands, NM to investigate the presence of two-phase abrasion in a different, non-idealized natural environment - a high-energy, eolian gypsum dunefield. Analysis of grain shapes from White Sands confirms the two-phase abrasion process, dependent upon mode of sediment transport. We find that large sand grains carried in saltation bed load transport exhibit shape change indicative of two-phase abrasion, while smaller particles carried in suspension do not. We observe rapid shape change in bed load particles approaching a convex shape, followed by slower reduction in grain axis dimensions. Confirmation of this process in a natural, non-idealized setting establishes two-phase abrasion as a general application for bed load transport.

  13. Groundwater Remediation and Alternate Energy at White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Fischer, Holger

    2008-01-01

    White Sands Test Facility Core Capabilities: a) Remote Hazardous Testing of Reactive, Explosive, and Toxic Materials and Fluids; b) Hypergolic Fluids Materials and Systems Testing; c) Oxygen Materials and System Testing; d) Hypervelocity Impact Testing; e)Flight Hardware Processing; and e) Propulsion Testing. There is no impact to any drinking water well. Includes public wells and the NASA supply well. There is no public exposure. Groundwater is several hundred feet below ground. No air or surface water exposure. Plume is moving very slowly to the west. Plume Front Treatment system will stop this westward movement. NASA performs on-going monitoring. More than 200 wells and zones are routinely sampled. Approx. 850 samples are obtained monthly and analyzed for over 300 different hazardous chemicals.

  14. Standards Development Activities at White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Baker, D. L.; Beeson, H. D.; Saulsberry, R. L.; Julien, H. L.; Woods, S. S.

    2003-01-01

    The development of standards and standard activities at the JSC White Sands Test Facility (WSTF) has been expanded to include the transfer of technology and standards to voluntary consensus organizations in five technical areas of importance to NASA. This effort is in direct response to the National Technology Transfer Act designed to accelerate transfer of technology to industry and promote government-industry partnerships. Technology transfer is especially important for WSTF, whose longterm mission has been to develop and provide vital propellant safety and hazards information to aerospace designers, operations personnel, and safety personnel. Meeting this mission is being accomplished through the preparation of consensus guidelines and standards, propellant hazards analysis protocols, and safety courses for the propellant use of hydrogen, oxygen, and hypergols, as well as the design and inspection of spacecraft pressure vessels and the use of pyrovalves in spacecraft propulsion systems. The overall WSTF technology transfer program is described and the current status of technology transfer activities are summarized.

  15. NASA White Sands Test Facility Totally Encapsulating Suit (TES) Boot Camp - Duration: 65 seconds.

    NASA Video Gallery

    The White Sands Test Facility Totally Encapsulating Suit (TES) Boot Camp prepares students to deal with normal propellant operations, emergency events, and pre-operation planning by engaging studen...

  16. NASA White Sands Test Facility Totally Encapsulating Suit (TES) Boot Camp - Duration: 71 seconds.

    NASA Video Gallery

    The NASA White Sands Test Facility Totally Encapsulating Suit (TES) Boot Camp prepares students to deal with normal propellant operations, emergency events, and pre-operation planning by engaging s...

  17. Rescue Simulation - NASA White Sands Test Facility Totally Encapsulating Suit (TES) Boot Camp - Duration: 70 seconds.

    NASA Video Gallery

    The White Sands Test Facility Totally Encapsulating Suit (TES) Boot Camp prepares students to deal with normal propellant operations, emergency events, and pre-operation planning by engaging studen...

  18. Overview of NASA White Sands Test Facility Composite Overwrapped Pressure Vessel Testing

    NASA Technical Reports Server (NTRS)

    Greene, Nathanael; Saulsberry, Regor; Thesken, John; Phoenix, Leigh

    2006-01-01

    This viewgraph presentation examines the White Sands Test Facility testing of Composite overwrapped pressure vessel (COPV). A COPV is typically a metallic liner overwrapped with a fiber epoxy matrix. There is a weight advantage over the traditional all metal design. The presentation shows pictures of the facilities at White Sands, and then examines some of the testing performed. The tests include fluids compatibility, and Kevlar COPV. Data for the Kevlar tests are given, and an analysis is reviewed. There is also a comparison between Carbon COPVs and the Kevlar COPVs.

  19. Solar cell power for field instrumentation at White Sands Missile Range

    Microsoft Academic Search

    J. Bond; D. H. Reckart Jr.; W. B. Milway

    1978-01-01

    The initial phase of an Instrumentation Development Project to explore and document what solar power can do for remote field instrumentation systems is described. The work scope consisted of selection, design, construction, test, and delivery of a solar cell power system for White Sands Missile Range. A Drone Formation Control System Interrogator was selected; a power supply was built and

  20. Solar cell power for field instrumentation at White Sands Missile range. Final report

    Microsoft Academic Search

    J. W. Jr.. Bond; D. H. Jr Reckart; W. B. Milway

    1978-01-01

    The initial phase of an Instrumentation Development Project to explore and document what solar power can do for remote field instrumentation systems is described. The work scope consisted of selection, design, construction, test, and delivery of a solar cell power system for White Sands Missile Range. A Drone Formation Control System Interrogator was selected; a power supply was built and

  1. Equatorial weathering, landform development and the formation of white sands in north western Kalimantan, Indonesia

    Microsoft Academic Search

    Michael Thomas; Martin Thorp; John McAlister

    1999-01-01

    The morphology and geochemistry of weathering profiles in Miocene granodiorites from the coastal lowlands of NW Kalimantan, Indonesia (1°N lat.), indicate long-term weathering rates, landform development and mechanisms for the formation of `white sands' found widely in valleys and depressions. Samples are analysed from convex hill, piedmont glacis, and valley slope profiles. All profiles above the saturated zone are strongly

  2. White Sands Dune Field, New Mexico: Age, dune dynamics and recent accumulations

    Microsoft Academic Search

    Gary Kocurek; Mary Carr; Ryan Ewing; Karen G. Havholm; Y. C. Nagar; A. K. Singhvi

    2006-01-01

    The White Sands Dune Field, situated within the Tularosa Basin in southern New Mexico, is thought to have been largely derived by a stepwise, progressive deflation of Pleistocene Lake Otero strata with the onset of regional aridity. Optically stimulated luminescence (OSL) dating of samples from a core that penetrated the gypsum accumulation of the dune field confirm a time of

  3. Meso-scale cooling effects of high albedo surfaces: Analysis of meteorological data from White Sands National Monument and White Sands Missile Range

    SciTech Connect

    Fishman, B.; Taha, H.; Akbari, H.

    1994-05-20

    Urban summer daytime temperatures often exceed those of the surrounding rural areas. Summer ``urban heat islands`` are caused by dark roofs and paved surfaces as well as the lack of vegetation. Researchers at Lawrence Berkeley Laboratory are interested in studying the effects of increasing the albedo of roof tops and paved surfaces in order to reduce the impacts of summer urban heat islands. Increasing the albedo of urban surfaces may reduce this heat island effect in two ways, directly and indirectly. The direct effect involves reducing surface temperature and, therefore, heat conduction through the building envelope. This effect of surface albedo on surface temperatures is better understood and has been quantified in several studies. The indirect effect is the impact of high albedo surfaces on the near surface air temperatures. Although the indirect effect has been modeled for the Los Angeles basin by Sailor, direct field observations are required. The objective of this report is to investigate the meso-scale climate of a large high albedo area and identify the effects of albedo on the near surface air temperature. To accomplish this task, data from several surface weather stations at White Sands, New Mexico were analyzed. This report is organized into six sections in addition to this introduction. The first gives the general geological, topographic, and meteorological background of White Sands. The second is a discussion of the basic surface meteorology of the White Sands region. This section is followed by a general discussion of the instrumentation and available data. The fourth section is a description of the method used for data analyis. The fifth section which presents the results of this analysis. Finally, the last section is the summary and conclusion, where a discussion of the results is presented.

  4. Energy Savings Opportunity Survey (ESOS), White Sands Missile Range, New Mexico. Final report

    SciTech Connect

    NONE

    1992-11-01

    The purpose of this study is to analyze the application of selected Energy Conservation Opportunities (ECOs) to designated buildings and systems at the White Sands Missile Range (WSMR). The study has nine elements: (1) Perform a field survey of designated buildings. (2) Evaluate ten ECOs applied selectively to 45 buildings in the Main Post Area (General ECOs). (3) Evaluate six specified ECOs at Building P300. (4) Perform complete energy surveys on Buildings P21140, P21695, and P24O72. (5) Evaluate the refurbishment of the chilled water plant in P24066 to serve four buildings in Launch Complex 38. (6) Identify and evaluate other ECOs (Contractor-identified ECOs). (7) Analyze historical electrical demand readings for the Main Post Area and recommend ways to reduce and limit peak demand (Demand Side Management). (8) Evaluate the feasibility of constructing a consolidated chilled water plant to serve the Tech Area. Consider thermal storage and cogeneration as alternatives. and (9) Present all findings and recommendations in a comprehensive report.

  5. Energy Savings Opportunity Survey (ESOS), White Sands Missile Range, New Mexico, volume 1, book 1

    SciTech Connect

    NONE

    1992-11-01

    The purpose of this study is to analyze the application of selected Energy Conservation Opportunities (ECOs) to designated buildings and systems at the White Sands Missile Range (WSMR). The study has nine elements: 1. Perform, a field survey of designated buildings. 2. Evaluate ten ECOs applied selectively to 45 buildings in the Main Post Area. (General ECOs). 3. Evaluate six specified ECOs at Building P30O. 4. Perform complete energy surveys on Buildings P21140, P21695, and P24072. 5. Evaluate the refurbishment of the chilled water plant in P24066 to serve four buildings in Launch Complex 38. 6. Identify and evaluate other ECOs. (Contractor-identified ECOs) 7. Analyze historical electrical demand readings for the Main Post Area and recommend ways to reduce and limit peak demand. (Demand Side Management) 8. Evaluate the feasibility of constructing a consolidated chilled water plant to serve the Tech Area. Consider thermal storage and cogeneration as alternatives. 9. Present all findings and recommendations in a comprehensive report.

  6. Mapping Playa Evaporite Minerals, White Sands, New Mexico Using Landsat ETM+

    NASA Astrophysics Data System (ADS)

    Ghrefat, H. A.; Goodell, P. C.

    2002-12-01

    Evaporite minerals are the main source of several industrial and agricultural minerals important to the U.S. and world economy. Landsat ETM+ data covering the White Sands, New Mexico have been used in this study. The White Sands Dune Field, Lake Lucero, and Alkali Flat have been chosen as target sites. The study aims to determine the number of evaporite mineral endmembers that can be detected and mapped using Landsat ETM+. Furthermore, the study also aims to determine the spatial distribution of fractional abundances of evaporite mineral endmembers assuming a linear mixing model. The Minimum Noise Fraction (MNF) transform and Principal Component Analysis (PCA) were employed to determine a reduced set of noise-free spectral bands. The Pixel Purity Index (PPI) and n-D Visualization (nDV) were conducted on the reduced set of spectral bands to identify spectrally pure evaporite mineral endmembers in the image. Mineral maps of the spatial distribution and relative abundance of evaporite minerals were performed using two different algorithms: Spectral Angle Mapper (SAM) and Linear Spectral Unmixing (LSU). Four evaporite mineral endmembers have been identified using Spectral Angle Mapper. These minerals are gypsum, halite, calcite, and thenardite. The results of Linear Spectral Unmixing showed that the most common and abundant evaporite mineral in the White Sands is gypsum. The results of Spectral Angle Mapper (SAM) and Linear Spectral Unmixing (LSU) are validated by collecting field samples from different locations within the White Sands. A good match has been determined between results of Landsat ETM+ data and field and laboratory work. Mapping of playa evaporite minerals is of potential importance for the goal of saline soil characterization, regional groundwater hydrology and quality, and mineral resource development.

  7. Evaluating the Emergency Notification Systems of the NASA White Sands Test

    NASA Technical Reports Server (NTRS)

    Chavez, Alfred Paul

    2004-01-01

    The problem was that the NASA Fire and Emergency Services did not know if the current emergency notification systems on the NASA White Sands Test Facility were appropriate for alerting the employees of an emergency. The purpose of this Applied Research Project was to determine if the current emergency notification systems of the White Sands Test Facility are appropriate for alerting the employees of an emergency. This was a descriptive research project. The research questions were: 1) What are similar facilities using to alert the employees of an emergency?; 2) Are the current emergency notification systems suitable for the community hazards on the NASA White Sands Test Facility?; 3) What is the NASA Fire and Emergency Services currently using to measure the effectiveness of the emergency notification systems?; and 4) What are the current training methods used to train personnel to the emergency notification systems at the NASA White Sands Test Facility? The procedures involved were to research other established facilities, research published material from credible sources, survey the facility to determine the facility perception of the emergency notification systems, and evaluate the operating elements of the established emergency notification systems for the facility. The results were that the current systems are suitable for the type of hazards the facility may endure. The emergency notification systems are tested frequently to ensure effectiveness in the event of an emergency. Personnel are trained and participate in a yearly drill to make certain personnel are educated on the established systems. The recommendations based on the results were to operationally improve the existing systems by developing and implementing one system that can overall notify the facility of a hazard. Existing procedures and training should also be improved to ensure that all personnel are educated on what to do when the emergency notification systems are activated.

  8. Definition and origin of the dune-field pattern at White Sands, New Mexico

    NASA Astrophysics Data System (ADS)

    Baitis, Elke; Kocurek, Gary; Smith, Virginia; Mohrig, David; Ewing, Ryan C.; Peyret, A.-P. B.

    2014-12-01

    A LiDAR-derived digital elevation model (DEM) of a representative portion of the White Sands Dune Field, New Mexico, allows for characterization of an unprecedented range of dune-field parameters and serves as a basis for pattern analysis. Dune-field parameters were measured and statistically analyzed for populations of dunes selected at random and occurring along transects. Populations sampled by these two different methods are comparable, but highlight the sensitivity of transect placement in a dune field that has pattern heterogeneity. Based upon coefficients of variation, pattern emerges at White Sands primarily because of a strong fabric of crestline orientation, and secondarily because of the regularity of spacing between dunes of similar shape as defined by sinuosity, height and length. Linear regression of dune parameters shows that dune geometric relationships vary primarily with crestline length, but there is little correlation between other parameters, including dune spacing and height. This result highlights the sensitivity of identifying topographic heterogeneity in a LiDAR-derived DEM, given that mean ratios conform to global averages. Stripping off the dunes in Matlab shows a terraced surface, which is interpreted to represent paleo-shorelines formed during relative still stands in the overall retreat of Lake Otero. Elevated bands of higher, more closely spaced dunes occur just leeward of the paleo-shorelines. A revised model for the White Sands Dune Field consists of the basinward progradation of successive dune-field segments. Each segment is associated with a paleo-shoreline, and consists of an upwind dune ridge, represented by the elevated bands, and a leeward dune field.

  9. Spacecraft propulsion systems test capability at the NASA White Sands Test Facility

    NASA Astrophysics Data System (ADS)

    Baker, Pleddie; Gorham, Richard

    The NASA White Sands Facility (WSTF), a component insallation of the Johnson Space Center, is located on a 94-square-mile site in southwestern New Mexico. WSTF maintains many unique capabilities to support its mission to test and evaluate spacecraft materials, components, and propulsion systems to enable the safe human exploration and utilization of space. WSTF has tested over 340 rocket engines with more than 2.5 million firings to date. Included are propulsion system testing for Apollo, Shuttle, and now Space Station as well as unmanned spacecraft such as Viking, Pioneer, and Mars Observer. This paper describes the current WSTF propulsion test facilities and capabilities.

  10. AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for NASA White Sands Test Facility

    SciTech Connect

    Stephen Schey; Jim Francfort

    2014-10-01

    This report focuses on the NASA White Sands Test Facility (WSTF) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of plug-in electric vehicles (PEVs) into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle (BEV) or plug-in hybrid electric vehicle (PHEV) (collectively plug-in electric vehicles, or PEVs) can fulfill the mission requirements.

  11. Limited energy study, Geodss Facility, White Sands Missile Range, New Mexico. Final report

    SciTech Connect

    NONE

    1995-11-01

    The purpose of this study is to identify and evaluate Energy Conservation Opportunities (ECOs), to determine their energy savings potential and economic feasibility, and to document results for possible future funding. The Ground Based Electro-Optical Deep Space Surveillance (GEODSS) Facility, Building 34568, is a windowless, concrete block structure approximately 10,000 square feet. The building is located on the northern end of the White Sands Missile Range in central New Mexico. The building consists of a large central computer room with perimeter offices. Concrete towers at three corners of the building are topped with telescopes in movable domes. The building is occupied 24 hours per day.

  12. Complex Conductivity Response to Nanomaterials in a Sand Matrix

    NASA Astrophysics Data System (ADS)

    Joyce, R.; Werkema, D.; Atekwana, E.; Atekwana, E.

    2008-12-01

    Nano-scale metallic particles are being used with increasing frequency in a variety of industrial, medical, and environmental remediation applications. The fate and transport of such materials in the subsurface is not fully understood, neither is the impact of these materials on human health. Materials at this small nano-scale sometimes have unusual physical properties which differ from larger sized particles of the same material. Feasibility experiments were performed to investigate the geoelectrical properties of nanomaterials in the environment. Five nanomaterials were selected for laboratory column experiments within a sand matrix. These nanomaterials included: Zero-Valent Iron, Cerium Dioxide, Titanium Dioxide, Zinc Oxide, and Silver. These materials were mixed at different concentrations (.025-2.5 weight percent) into a medium grained silica sand matrix and saturated with simulated groundwater then packed into PVC columns. Complex conductivity measurements (0.1-12 kHz) were performed on these various columns. Preliminary results suggest that there is a minimal geoelectrical response associated with all of the materials except for silver as a function of increasing concentration of particles. These results are counter to our expected results which predicted that we should see a noticeable response from the materials due to their increased surface area. Further experiments are being planned to further evaluate how well geoelectrical techniques are suited for detecting these materials in geologic media under various geochemical environments.

  13. Complex resistivity signatures of ethanol in sand-clay mixtures

    USGS Publications Warehouse

    Personna, Yves Robert; Slater, Lee; Ntarlagiannis, Dimitrios; Werkema, Dale; Szabo, Zoltan

    2013-01-01

    We performed complex resistivity (CR) measurements on laboratory columns to investigate changes in electrical properties as a result of varying ethanol (EtOH) concentration (0% to 30% v/v) in a sand–clay (bentonite) matrix. We applied Debye decomposition, a phenomenological model commonly used to fit CR data, to determine model parameters (time constant: ?, chargeability: m, and normalized chargeability: mn). The CR data showed a significant (P ? 0.001) time-dependent variation in the clay driven polarization response (~ 12 mrad) for 0% EtOH concentration. This temporal variation probably results from the clay–water reaction kinetics trending towards equilibrium in the sand–clay–water system. The clay polarization is significantly suppressed (P ? 0.001) for both measured phase (?) and imaginary conductivity (??) with increasing EtOH concentration. Normalized chargeability consistently decreases (by up to a factor of ~ 2) as EtOH concentration increases from 0% to 10% and 10 to 20%, respectively. We propose that such suppression effects are associated with alterations in the electrical double layer (EDL) at the clay–fluid interface due to (a) strong EtOH adsorption on clay, and (b) complex intermolecular EtOH–water interactions and subsequent changes in ionic mobility on the surface in the EDL. Changes in the CR data following a change of the saturating fluid from EtOH 20% to plain water indicate strong hysteresis effects in the electrical response, which we attribute to persistent EtOH adsorption on clay. Our results demonstrate high sensitivity of CR measurements to clay–EtOH interactions in porous media, indicating the potential application of this technique for characterization and monitoring of ethanol contamination in sediments containing clays.

  14. In-flight Absolute Radiometric Calibration of the Thematic Mapper. [White Sands, New Mexico

    NASA Technical Reports Server (NTRS)

    Palmer, J.; Slater, P. N. (principal investigators); Castle, K. R.; Holm, R. G.; Kastner, C. J.; Dinguirard, M.; Ezra, C. E.; Jackson, R. D.; Savage, R. K.

    1984-01-01

    Ground spectral reflectance and atmospheric spectral optical depth measurements made at White Sands, New Mexico were used with an atmospheric radiative transfer program to determine the spectral radiance at the entrance pupil of the LANDSAT-4 TM. Comparison with the output digital counts of the TM, when imaging the measured ground area, provided an absolute calibration for five detectors in TM bands 2, 3, and 4. By reference to an adjacent, larger uniform area, the calibration was extended to all 16 detectors in each of three bands. Preflight calibration results agreed with these inflight measurements to 6.6%, 2.4%, and 12.9% in bands 2,3, and 4, respectively.

  15. Energy study (EEAP) at MELSTF, White Sands Missile Range, New Mexico. Volume I. Final report

    SciTech Connect

    Carter, J.; Howard, D.; Pieper, C.A.

    1996-08-23

    This energy conservation study was performed by Huitt-Zollars Inc., for the U.S. Army Engineer District (USAED), Fort Worth, under contract number DECAC63-94-D-0015. The study was conducted at MELSTF on the White Sands Missile Range in New Mexico, between September 21, 1995 and April 28, 1996. The site survey, data collection and technical analysis were performed by John Carter, E.I.T, Denney Howard, P.E. and C.A. Pieper, P.E.. The purpose of the study was to perform a limited site survey of specific buildings at the facility, identify specific Energy Conservation Opportunities (ECOs) that exist, and then evaluate these ECOs for technical and economic feasibility. These ECOs were open to all methods of energy conservation which were reasonable and practical.

  16. Origin of coarsely crystalline gypsum domes in a saline playa environment at the White Sands National Monument, New Mexico

    Microsoft Academic Search

    Anna Szynkiewicz; Craig H. Moore; Mihaela Glamoclija; David Bustos; Lisa M. Pratt

    2010-01-01

    Dome-like structures up to 3 m in height, composed predominantly of coarse crystals of selenite gypsum, occur on the surface of Alkali Flat, a saline playa lake in White Sands National Monument, New Mexico. The structures were investigated using field observations, aerial images, and geochemical methods. The domes are inferred to be remnants of lake sediments that have been preserved

  17. Habitat Specialization by Birds in Western Amazonian White-sand Forests Jose Alvarez Alonso1,4

    E-print Network

    Fine, Paul V.A.

    composition of the avifauna of the white-sand forests at six localities in the region was sampled; Peruvian Amazonia; river barriers, specialized avifauna; tropical conservation; varillal. WESTERN AMAZONIA in northern Amazonia. Borges (2004) conducted a detailed survey of the WSF avifauna of Jau National Park

  18. 6. MCDONALD RANCH: AERIAL VIEW OF RANCH COMPLEX, LOOKING SOUTH ...

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

    6. MCDONALD RANCH: AERIAL VIEW OF RANCH COMPLEX, LOOKING SOUTH TOWARD NORTHERN TIP OF SAN ANDREAS RANGE - White Sands Missile Range, Trinity Site, Vicinity of Routes 13 & 20, White Sands, Dona Ana County, NM

  19. Genetic features of soils on marine sands and their windblown derivatives on the White Sea coast (the Kola Peninsula)

    NASA Astrophysics Data System (ADS)

    Pereverzev, V. N.; Kazakov, L. A.; Chamin, V. A.

    2011-01-01

    The Quaternary deposits on the Tersk coast of the White Sea are represented by marine deposits (the Tersk sands) enriched in the sea-sorted eluvium of the red Tersk sandstone. These deposits and the soils developed from them are characterized by the predominance of the fine sand fraction and the absence of gravel and the coarser fractions. The sediments derived from the red Tersk sandstone have an impoverished chemical composition (the silica content reaches 75-80%). The iron-illuvial podzols developed from them are characterized by the slightly pronounced differentiation of the main oxides and by the eluvial-illuvial redistribution of the amorphous Al and Fe compounds. Sandy soils—psammozems—with undifferentiated soil profiles are developed from windblown sands subjected to afforestation and from coastal marine sands under a relatively thin natural plant cover. Iron-illuvial podzols buried under a thin sand layer preserve the Al-Fe-humus type of the profile differentiation. In the recently deposited sand layer, the eluvial-illuvial redistribution of the chemical elements is absent.

  20. Potential for substitution of geothermal energy at domestic defense installations and White Sands Missile Range

    SciTech Connect

    Bakewell, C.A.; Renner, J.L.

    1982-01-01

    Geothermal resources that might provide substitute energy at any of 76 defense installations are identified and evaluated. The geologic characteristics and related economics of potential geothermal resources located at or near the 76 installations were estimated. The geologic assessment identified 18 installations with possible geothermal resources and 4 Atlantic Coastal Plain resource configurations that represented the alternatives available to East Coast bases. These 18 locations and 4 resource configurations, together with 2 possible resources at the White Sands Missile Range and a potential resource at Kings Bay, Georgia, were examined to determine the relative economics of substituting potential geothermal energy for part or all of the existing oil, gas, and electrical energy usage. Four of the military installations - Mountain Home, Norton, Hawthorne, and Sierra - appear to be co-located with possible geothermal resources which, if present, might provide substitute energy at or below current market prices for oil. Six additional locations - Ellsworth, Luke, Williams, Bliss, Fallon, and Twentynine Palms - could become economically attractive under certain conditions. No geothermal resource was found to be economically competitive with natural gas at current controlled prices. Generation of electric power at the locations studied is estimated to be uneconomic at present.

  1. Development of CFC-Free Cleaning Processes at the NASA White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Beeson, Harold; Kirsch, Mike; Hornung, Steven; Biesinger, Paul

    1995-01-01

    The NASA White Sands Test Facility (WSTF) is developing cleaning and verification processes to replace currently used chlorofluorocarbon-113- (CFC-113-) based processes. The processes being evaluated include both aqueous- and solvent-based techniques. The presentation will include the findings of investigations of aqueous cleaning and verification processes that are based on a draft of a proposed NASA Kennedy Space Center (KSC) cleaning procedure. Verification testing with known contaminants, such as hydraulic fluid and commonly used oils, established correlations between nonvolatile residue and CFC-113. Recoveries ranged from 35 to 60 percent of theoretical. WSTF is also investigating enhancements to aqueous sampling for organics and particulates. Although aqueous alternatives have been identified for several processes, a need still exists for nonaqueous solvent cleaning, such as the cleaning and cleanliness verification of gauges used for oxygen service. The cleaning effectiveness of tetrachloroethylene (PCE), trichloroethylene (TCE), ethanol, hydrochlorofluorocarbon-225 (HCFC-225), tert-butylmethylether, and n-Hexane was evaluated using aerospace gauges and precision instruments and then compared to the cleaning effectiveness of CFC-113. Solvents considered for use in oxygen systems were also tested for oxygen compatibility using high-pressure oxygen autoignition and liquid oxygen mechanical impact testing.

  2. A laboratory study of subjective response to sonic booms measured at White Sands Missile Range

    NASA Technical Reports Server (NTRS)

    Sullivan, Brenda M.; Leatherwood, Jack D.

    1993-01-01

    The Sonic Boom Simulator of the Langley Research Center was used to quantify subjective loudness response to boom signatures consisting of: (1) simulator reproductions of booms recently recorded at White Sands Missile Range; (2) idealized N-waves; and (3) idealized booms having intermediate shocks. The booms with intermediate shocks represented signatures derived from CFD predictions. The recorded booms represented those generated by F15 and T38 aircraft flyovers and represented a variety of waveforms reflecting the effects of propagation through a turbulent atmosphere. These waveforms included the following shape categories: N-waves, peaked, rounded, and U-shaped. Results showed that Perceived Level and Zwicker Loudness Level were good estimators of the loudness of turbulence modified sonic booms. No significant differences were observed between loudness responses for the several shape categories when expressed in terms of Perceived Level. Thus, Perceived Level effectively accounted for waveform differences due to turbulence. Idealized booms with intermediate shocks, however, were rated as being approximately 2.7 dB(PL) less loud than the recorded signatures. This difference was not accounted for by PL.

  3. Dust devils at White Sands Missile Range, New Mexico. 1. Temporal and spatial distribution

    SciTech Connect

    Snow, J.T.; McClelland, T.M. (Purdue Univ., Lafayette, IN (USA))

    1990-08-20

    From May 13, through August 21, 1986, and again from April 3, through May 28, 1987, a dust devil census was conducted at the Permanent High Explosive Test Site on White Sands Missile Range, New Mexico. In a 260-km{sup 2} observation area, a total of 3,134 dust devils were counted on 97 days (out of 112 observing days). Within the observation area, the dust devils were concentrated in a relatively small area and showed strong correlation with roadways and other cleared areas. However, from the summer of 1986 to the spring of 1987, the center of activity shifted from a relatively undisturbed region to an area whose surface had been recently modified. This shift is attributed to changes in soil moisture and surface thermal properties. It is suggested that the co-location of the center of activity in 1987 with the modified surface is an example of inadvertent weather modification on a very local scale. The dust devils had a daily distribution very similar to that found by Sinclair (1969) in comparable terrain in the vicinity of Tucson, Arizona. The time of the first observed dust devil was very regular on days with dry surface conditions at sunrise and clear skies through the morning. The time of the first dust devil was delayed and the degree of activity reduced if precipitation had occurred on a previous day in the observation area. The production of dust devils often ended abruptly with the onset of an afternoon thundershower in the observation area.

  4. Aqueous Cleaning and Validation for Space Shuttle Propulsion Hardware at the White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Hornung, Steven D.; Biesinger, Paul; Kirsch, Mike; Beeson, Harold; Leuders, Kathy

    1999-01-01

    The NASA White Sands Test Facility (WSTF) has developed an entirely aqueous final cleaning and verification process to replace the current chlorofluorocarbon (CFC) 113 based process. This process has been accepted for final cleaning and cleanliness verification of WSTF ground support equipment. The aqueous process relies on ultrapure water at 50 C (323 K) and ultrasonic agitation for removal of organic compounds and particulate. The cleanliness is verified bv determining the total organic carbon (TOC) content and filtration with particulate counting. The effectiveness of the aqueous methods for detecting hydrocarbon contamination and particulate was compared to the accepted CFC 113 sampling procedures. Testing with known contaminants, such as hydraulic fluid and cutting and lubricating oils, to establish a correlation between aqueous TOC and CFC 113 nonvolatile residue (NVR) was performed. Particulate sampling on cleaned batches of hardware that were randomly separated and sampled by the two methods was performed. This paper presents the approach and results, and discusses the issues in establishing the equivalence of aqueous sampling to CFC 113 sampling, while describing the approach for implementing aqueous techniques on Space Shuttle Propulsion hardware.

  5. Laser-extinction and high-resolution atmospheric transmission measurements conducted at White Sands Missile Range, New Mexico

    Microsoft Academic Search

    J. A. Dowling; S. T. Hanley; J. A. Curcio; C. O. Gott; M. A. Woytko

    1980-01-01

    Measurements of atmospheric transmission over a 6.4 km path were conducted in March 1979 at White Sands Missile Range (WSMR), New Mexico. A deuterium fluoride (DF) laser and a high-resolution Fourier transform spectrometer (FTS) system were used to generate high-quality transmission spectra of the 6.4 km path accurate to + or - 3% in absolute transmission. Details of the procedures

  6. Multiscale bed form interactions and their implications for the abruptness and stability of the downwind dune field margin at White Sands, New Mexico, USA

    NASA Astrophysics Data System (ADS)

    Pelletier, Jon D.; Jerolmack, Douglas J.

    2014-11-01

    The downwind margin of White Sands dune field is an abrupt transition from mobile aeolian dunes to a dune-free vegetated surface. This margin is also relatively stable; over the past 60 years it has migrated several times more slowly than the slowest dunes within the dune field, resulting in a zone of dune coalescence, aggradation, and, along most of the margin, development of a dune complex (i.e., dunes superimposed on draas). Repeat terrestrial laser scanning surveys conducted over a 3 month period demonstrate that sediment fluxes within the dune complex decrease on approach to the margin. Computational fluid dynamics modeling indicates that this decrease is due, in part, to a decrease in mean turbulent bed shear stress on the lee side of the dune complex as a result of flow line divergence or sheltering of the lee-side dunes by the stoss side of the dune complex. Conservation of mass demands that this decrease in bed shear stress causes aggradation. We speculate that aggradation on the lee side of the dune complex further enhances the sheltering effect in a positive feedback, contributing to the growth and/or maintenance of the dune complex and a relatively abrupt and stable dune field margin. Our model and data add to a growing body of evidence that aeolian dune field patterns are influenced by feedbacks that occur at scales larger than individual dunes.

  7. Dust Plume Modeling from Ranges and Maneuver Areas on Fort Bliss and the White Sands Missile Range: Final Report

    SciTech Connect

    Chapman, Elaine G.; Barnard, James C.; Rutz, Frederick C.; Pekour, Mikhail S.; Rishel, Jeremy P.; Shaw, William J.

    2009-05-04

    The potential for air quality impacts from heavy mechanized vehicles operating on and between the unpaved main supply routes at Fort Bliss and White Sands Missile Range was investigated. This report details efforts by the staff of Pacific Northwest National Laboratory for the Fort Bliss Directorate of Environment in this investigation. Dust emission and dispersion from typical move-out activities occurring on the installations were simulated using the atmospheric modeling system DUSTRAN. Major assumptions associated with designing the modeling scenarios are summarized and results of simulations conducted under these assumptions are presented for four representative meteorological periods.

  8. Community complexity: Stratifying monitoring schemes within a desert sand dune landscape

    Microsoft Academic Search

    C. W. Barrows; M. F. Allen

    2007-01-01

    Landscapes of desert sand dunes are sometimes viewed as biologically and ecologically homogeneous, yet they can be deceptively complex. We analysed temporal and spatial patterns of species occurrence across a desert dune landscape to clarify the utility of a priori community divisions and how those designations facilitate evaluations of whether conservation objectives are being met, and whether adaptive management approaches

  9. Growth of mycorrhizal jack pine (Pinus banksiana) and white spruce (Picea glauca) seedlings planted in oil sands reclaimed areas.

    PubMed

    Onwuchekwa, Nnenna E; Zwiazek, Janusz J; Quoreshi, Ali; Khasa, Damase P

    2014-08-01

    The effectiveness of ectomycorrhizal inoculation at the tree nursery seedling production stage on growth and survival was examined in jack pine (Pinus banksiana) and white spruce (Picea glauca) planted in oil sands reclamation sites. The seedlings were inoculated with Hebeloma crustuliniforme strain # UAMH 5247, Suillus tomentosus strain # UAMH 6252, and Laccaria bicolor strain # UAMH 8232, as individual pure cultures and in combinations. These treatments were demonstrated to improve salinity resistance and water uptake in conifer seedlings. The field responses of seedlings to ectomycorrhizal inoculation varied between plant species, inoculation treatments, and measured parameters. Seedling inoculation resulted in higher ectomycorrhizal colonization rates compared with non-inoculated control, which had also a relatively small proportion of roots colonized by the nursery contaminant fungi identified as Amphinema byssoides and Thelephora americana. Seedling inoculation had overall a greater effect on relative height growth rates, dry biomass, and stem volumes in jack pine compared with white spruce. However, when examined after two growing seasons, inoculated white spruce seedlings showed up to 75% higher survival rates than non-inoculated controls. The persistence of inoculated fungi in roots of planted seedlings was examined at the end of the second growing season. Although the inoculation with H. crustuliniforme triggered growth responses, the fungus was not found in the roots of seedlings at the end of the second growing season suggesting a possibility that the observed growth-promoting effect of H. crustuliniforme may be transient. The results suggest that the inoculation of conifer seedlings with ectomycorrhizal fungi could potentially be carried out on a large scale in tree nurseries to benefit postplanting performance in oil sands reclamation sites. However, these practices should take into consideration the differences in responses between the different plant species and fungal strains. PMID:24424508

  10. Additive surface complexation modeling of uranium(VI) adsorption onto quartz-sand dominated sediments.

    PubMed

    Dong, Wenming; Wan, Jiamin

    2014-06-17

    Many aquifers contaminated by U(VI)-containing acidic plumes are composed predominantly of quartz-sand sediments. The F-Area of the Savannah River Site (SRS) in South Carolina (USA) is an example. To predict U(VI) mobility and natural attenuation, we conducted U(VI) adsorption experiments using the F-Area plume sediments and reference quartz, goethite, and kaolinite. The sediments are composed of ?96% quartz-sand and 3-4% fine fractions of kaolinite and goethite. We developed a new humic acid adsorption method for determining the relative surface area abundances of goethite and kaolinite in the fine fractions. This method is expected to be applicable to many other binary mineral pairs, and allows successful application of the component additivity (CA) approach based surface complexation modeling (SCM) at the SRS F-Area and other similar aquifers. Our experimental results indicate that quartz has stronger U(VI) adsorption ability per unit surface area than goethite and kaolinite at pH ? 4.0. Our modeling results indicate that the binary (goethite/kaolinite) CA-SCM under-predicts U(VI) adsorption to the quartz-sand dominated sediments at pH ? 4.0. The new ternary (quartz/goethite/kaolinite) CA-SCM provides excellent predictions. The contributions of quartz-sand, kaolinite, and goethite to U(VI) adsorption and the potential influences of dissolved Al, Si, and Fe are also discussed. PMID:24865372

  11. GROWTH AND COMPLEXITY OF WHITE CLOVER STOLONS IN RESPONSE TO BIOTIC AND ABIOTIC STRESS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    White clover (Trifolium repens L.) persists in mixed-species swards mainly by clonal growth of stolons. Morphologically complex (i.e., highly branched stolons) plants of white clover generally persist longer. We hypothesized that biotic and abiotic stresses limit white clover production on grazing l...

  12. Compilation of hydrologic data for White Sands pupfish habitat and nonhabitat areas, northern Tularosa Basin, White Sands Missile Range and Holloman Air Force Base, New Mexico, 1911-2008

    USGS Publications Warehouse

    Naus, C.A.; Myers, R.G.; Saleh, D.K.; Myers, N.C.

    2014-01-01

    The White Sands pupfish (Cyprinodon tularosa), listed as threatened by the State of New Mexico and as a Federal species of concern, is endemic to the Tularosa Basin, New Mexico. Because water quality can affect pupfish and the environmental conditions of their habitat, a comprehensive compilation of hydrologic data for pupfish habitat and nonhabitat areas in the northern Tularosa Basin was undertaken by the U.S. Geological Survey in cooperation with White Sands Missile Range. The four locations within the Tularosa Basin that are known pupfish habitat areas are the Salt Creek, Malpais Spring and Malpais Salt Marsh, Main Mound Spring, and Lost River habitat areas. Streamflow data from the Salt Creek near Tularosa streamflow-gaging station indicated that the average annual mean streamflow and average annual total streamflow for water years 1995–2008 were 1.35 cubic feet per second (ft3/s) and 983 acre-feet, respectively. Periods of no flow were observed in water years 2002 through 2006. Dissolved-solids concentrations in Salt Creek samples collected from 1911 through 2007 ranged from 2,290 to 66,700 milligrams per liter (mg/L). The average annual mean streamflow and average annual total streamflow at the Malpais Spring near Oscura streamflow-gaging station for water years 2003–8 were 6.81 ft3/s and 584 acre-feet, respectively. Dissolved-solids concentrations for 16 Malpais Spring samples ranged from 3,882 to 5,500 mg/L. Isotopic data for a Malpais Spring near Oscura water sample collected in 1982 indicated that the water was more than 27,900 years old. Streamflow from Main Mound Spring was estimated at 0.007 ft3/s in 1955 and 1957 and ranged from 0.02 to 0.07 ft3/s from 1996 to 2001. Dissolved-solids concentrations in samples collected between 1955 and 2007 ranged from an estimated 3,760 to 4,240 mg/L in the upper pond and 4,840 to 5,120 mg/L in the lower pond. Isotopic data for a Main Mound Spring water sample collected in 1982 indicated that the water was about 19,600 years old. Dissolved-solids concentrations of Lost River samples collected from 1984 to 1999 ranged from 8,930 to 118,000 (estimated) mg/L. Dissolved-solids concentrations in samples from nonhabitat area sites ranged from 1,740 to 54,200 (estimated) mg/L. In general, water collected from pupfish nonhabitat area sites tends to have larger proportions of calcium, magnesium, and sulfate than water from pupfish habitat area sites. Water from springs associated with mounds in pupfish nonhabitat areas was of a similar type (calcium-sulfate) to water associated with mounds in pupfish habitat areas. Alkali Spring had a sodium-chloride water type, but the proportions of sodium-chloride and magnesium-sulfate are unique as compared to samples from other sites.

  13. Origin of coarsely crystalline gypsum domes in a saline playa environment at the White Sands National Monument, New Mexico

    NASA Astrophysics Data System (ADS)

    Szynkiewicz, Anna; Moore, Craig H.; Glamoclija, Mihaela; Bustos, David; Pratt, Lisa M.

    2010-06-01

    Dome-like structures up to 3 m in height, composed predominantly of coarse crystals of selenite gypsum, occur on the surface of Alkali Flat, a saline playa lake in White Sands National Monument, New Mexico. The structures were investigated using field observations, aerial images, and geochemical methods. The domes are inferred to be remnants of lake sediments that have been preserved from Holocene eolian erosion due to higher cementation resulting from crystallization of large gypsum (selenite) crystals in the playa's clay-rich sediments. Low ?2H values of the selenite, from -90 to -69 ‰, suggest precipitation from saturated solutions associated with groundwater seepage in the playa related to the upward flows of groundwater, primarily fed by meteoric water rather than the evaporation of the playa water. Values of ?34S for selenite range from 12.1 to 13.8 ‰ (median 13.0 ‰) and are notably higher than the dissolved sulfate in the modern groundwater system that has ?34S values from 10.2 to 11.8 ‰ (median 11.4 ‰). The two main regional sources of sulfate are Middle Permian evaporites with median ?34S values of 12.0 ‰ and Lower Permian evaporites with median ?34S values of 13.0 ‰. The ?34S values measured in domes suggest their formation during a period of time when groundwater seepage might have been dominated by deeply circulating water that interacted with Lower Permian evaporites buried in the basin center. The apparent alignments of domes suggest that past groundwater seepage was controlled by fractures beneath Alkali Flat which are associated with a regional fault system in the area.

  14. Ecological Responses to Hydrogeomorphic Fluctuations in a Sand Bed Prairie River: River Complexity, Habitat Availability, and Benthic Invertebrates

    E-print Network

    O'Neill, Brian James

    2010-04-02

    Ecological Responses to Hydrogeomorphic Fluctuations in a Sand Bed Prairie River: River Complexity, Habitat Availability, and Benthic Invertebrates By Brian J. O’Neill Submitted to the graduate degree program in Ecology and Evolutionary..., Habitat Availability, and Benthic Invertebrates Committee: _____________________________ Chairperson Date Approved_____________________ 3 Abstract Rivers...

  15. An investigation of several aspects of LANDSAT-5 data quality. [Palmer County, Shelby, mt; White sands, NM; Great Salt Lake, UT; San Matted Bridge and Sacramento, California

    NASA Technical Reports Server (NTRS)

    Wrigley, R. C. (principal investigator)

    1984-01-01

    Band-to-band registration, geodetic registration, interdector noise, and the modulation transfer function (MTE) are discussed for the Palmer County; TX scene. Band combinations for several LANDSAT 4 and LANDSAT 5 scenes; the geodetic registration test for the Sacramento, CA area; periodic noise components in TM band 5; and grey level measurements by detector for Great Salt Lake (UT) dark water forescans and backscans are considered. Results of MTF analyses of the San Mateo Bridge and of TM high resolution and aerial Daedalus scanner imagery are consistent and appear to be repeatable. An oil-on-sand target was constructed on the White Sands Missile Range in New Mexico. The two-image analysis procedure used is summarized.

  16. Airborne Measurements of Aerosol Emissions From the Alberta Oil Sands Complex

    NASA Astrophysics Data System (ADS)

    Howell, S. G.; Clarke, A. D.; McNaughton, C. S.; Freitag, S.

    2012-12-01

    The Alberta oil sands contain a vast reservoir of fossil hydrocarbons. The extremely viscous bitumen requires significant energy to extract and upgrade to make a fluid product suitable for pipelines and further refinement. The mining and upgrading process constitute a large industrial complex in an otherwise sparsely populated area of Canada. During the ARCTAS project in June/July 2008, while studying forest fire plumes, the NASA DC-8 and P-3B flew through the plume a total of 5 times. Once was a coordinated visit by both aircraft; the other 3 were fortuitous passes downwind. One study has been published about gas emissions from the complex. Here we concentrate on aerosol emissions and aging. As previously reported, there appear to be at least 2 types of plumes produced. One is an industrial-type plume with vast numbers of ultrafine particles, SO2, sulfate, black carbon (BC), CO, and NO2. The other, probably from the mining, has more organic aerosol and BC together with dust-like aerosols at 3 ?m and a 1 ?m mode of unknown origin. The DC-8 crossed the plume about 10 km downwind of the industrial site, giving time for the boundary layer to mix and enabling a very crude flux calculation suggesting that sulfate and organic aerosols were each produced at about 500 g/s (estimated errors are a factor of 2, chiefly due to concerns about vertical mixing). Since this was a single flight during a project dedicated to other purposes and operating conditions and weather may change fluxes considerably, this may not be a typical flux. As the plume progresses downwind, the ultrafine particles grow to sizes effective as cloud condensation nucei (CCN), SO2 is converted to sulfate, and organic aerosol is produced. During fair weather in the summer, as was the case during these flights, cloud convection pumps aerosol above the mixed layer. While the aerosol plume is difficult to detect from space, NO2 is measured by the OMI instrument an the Aura satellite and the oil sands plume often exceeds the detection limit. There is a rough correlation between NO2 and aerosol, so it may be possible to indirectly monitor aerosol production.

  17. Radiological survey and evaluation of the fallout area from the Trinity test: Chupadera Mesa and White Sands Missile Range, New Mexico

    SciTech Connect

    Hansen, W.R.; Rodgers, J.C.

    1985-06-01

    Current radiological conditions were evaluated for the site of the first nuclear weapons test, the Trinity test, and the associated fallout zone. The test, located on White Sands Missile Range, was conducted as part of the research with nuclear materials for the World War II Manhattan Engineer District atomic bomb project. Some residual radioactivity attributable to the test was found in the soils of Ground Zero on White Sands Missile Range and the areas that received fallout from the test. The study considered relevant information including historical records, environmental data extending back to the 1940s, and new data acquired by field sampling and measurements. Potential exposures to radiation were evaluated for current land uses. Maximum estimated doses on Chupadera Mesa and other uncontrolled areas are less than 3% of the DOE Radiation Protection Standards (RPSs). Radiation exposures during visits to the US Army-controlled Ground Zero area are less than 1 mrem per annual visit or less than 0.2% of the RPS for a member of the public. Detailed data and interpretations are provided in appendixes. 14 figs., 45 tabs.

  18. Application of solid state silicone-29 and carbon-13 nuclear magnetic resonance spectroscopy to the characterization of inorganic matter-humic complexes in Athabasca oil sands

    SciTech Connect

    Kotlyar, L.S.; Ripmeester, J.A.

    1988-06-01

    The ease of bitumen recovery from oil sand by hot or cold water separation techniques depends upon the surface properties of the components, especially water wet character of the clay and sand particles. Oil wetting of some of the oils and sand solids is believed to be caused by the presence of humic matter-non-crystalline inorganic complexes. Characterization of these complexes using solid state carbon-13 and silicon-29 magic spinning angle (MAS) NMR spectroscopy was the purpose of the present work.

  19. Results of calibrations of the NOAA-11 AVHRR made by reference to calibrated SPOT imagery at White Sands, N.M

    NASA Technical Reports Server (NTRS)

    Nianzeng, Che; Grant, Barbara G.; Flittner, David E.; Slater, Philip N.; Biggar, Stuart F.; Jackson, Ray D.; Moran, M. S.

    1991-01-01

    The calibration method reported here makes use of the reflectances of several large, uniform areas determined from calibrated and atmospherically corrected SPOT Haute Resolution Visible (HRV) scenes of White Sands, New Mexico. These reflectances were used to predict the radiances in the first two channels of the NOAA-11 Advanced Very High Resolution Radiometer (AVHRR). The digital counts in the AVHRR image corresponding to these known reflectance areas were determined by the use of two image registration techniques. The plots of digital counts versus pixel radiance provided the calibration gains and offsets for the AVHRR. A reduction in the gains of 4 and 13 percent in channels 1 and 2 respectively was found during the period 1988-11-19 to 1990-6-21. An error budget is presented for the method and is extended to the case of cross-calibrating sensors on the same orbital platform in the Earth Observing System (EOS) era.

  20. Friction evaluation of unpaved, gypsum-surface runways at Northrup Strip, White Sands Missile Range, in support of Space Shuttle Orbiter landing and retrieval operations

    NASA Technical Reports Server (NTRS)

    Yager, T. J.; Horne, W. B.

    1980-01-01

    Friction measurement results obtained on the gypsum surface runways at Northrup Strip, White Sands Missile Range, N. M., using an instrumented tire test vehicle and a diagonal braked vehicle, are presented. These runways were prepared to serve as backup landing and retrieval sites to the primary sites located at Dryden Flight Research Center for shuttle orbiter during initial test flights. Similar friction data obtained on paved and other unpaved surfaces was shown for comparison and to indicate that the friction capability measured on the dry gypsum surface runways is sufficient for operations with the shuttle orbiter and the Boeing 747 aircraft. Based on these ground vehicle friction measurements, estimates of shuttle orbiter and aircraft tire friction performance are presented and discussed. General observations concerning the gypsum surface characteristics are also included and several recommendations are made for improving and maintaining adequate surface friction capabilities prior to the first shuttle orbiter landing.

  1. Diffusion tensor imaging in studying white matter complexity: a gap junction hypothesis.

    PubMed

    Abdallah, Chadi G; Tang, Cheuk Y; Mathew, Sanjay J; Martinez, Jose; Hof, Patrick R; Perera, Tarique D; Shungu, Dikoma C; Gorman, Jack M; Coplan, Jeremy D

    2010-05-21

    The role of the prefrontal cortex as an executive oversight of posterior brain regions raises the question of the extent to which the anterior regions of the brain interconnect with the posterior regions. The aim of this study is to test the complexity of rostral white matter tracts, which connect anterior and posterior brain regions, in comparison to caudal white matter tracts and the corpus callosum. Diffusion tensor imaging (DTI) is a modality that measures fractional anisotropy (FA). Higher white matter complexity could result in a decrease of FA, possibly through denser intersection of fiber tracts. DTI was used to determine regional FA in 9 healthy bonnet macaques (Macaca radiata). Four regions of interest were included: anterior and posterior limbs of the internal capsule, the occipital lobe white matter, and the corpus callosum. FA of the anterior limbs of the internal capsule was lowest compared to all other regions of interest (Newman-Keuls (N-K); p<0.0001), whereas FA of the corpus callosum was highest (N-K; p<0.0001). The posterior limbs of the internal capsule and the occipital white matter were not distinguishable but exhibited intermediate FA in comparison to the former (N-K; p<0.0001) and the latter (N-K; p<0.0001). The current study demonstrates that FA, a measure of white matter complexity, can vary markedly as a function of region of interest. Moreover, validation of these findings using neurohistological studies and replication in human samples appears warranted. PMID:20371267

  2. Diffusion tensor imaging in studying white matter complexity: A gap junction hypothesis

    PubMed Central

    Abdallah, Chadi G.; Tang, Cheuk Y.; Mathew, Sanjay J.; Martinez, Jose; Hof, Patrick R.; Perera, Tarique D.; Shungu, Dikoma C.; Gorman, Jack M.; Coplan, Jeremy D.

    2010-01-01

    The role of the prefrontal cortex as an executive oversight of posterior brain regions raises the question of the extent to which the anterior regions of the brain interconnect with the posterior regions. The aim of this study is to test the complexity of rostral white matter tracts, which connect anterior and posterior brain regions, in comparison to caudal white matter tracts and the corpus callosum. Diffusion tensor imaging (DTI) is a modality that measures fractional anisotropy (FA). Higher white matter complexity could result in a decrease of FA, possibly through denser intersection of fiber tracts. DTI was used to determine regional FA in 9 healthy bonnet macaques (Macaca radiata). Four regions of interest were included: anterior and posterior limbs of the internal capsule, the occipital lobe white matter, and the corpus callosum. FA of the anterior limbs of the internal capsule was lowest compared to all other regions of interest (Newman-Keuls (N-K); p < 0.0001), whereas FA of the corpus callosum was highest (N-K; p < 0.0001). The posterior limbs of the internal capsule and the occipital white matter were not distinguishable but exhibited intermediate FA in comparison to the former (N-K; p < 0.0001) and the latter (N-K; p < 0.0001). The current study demonstrates that FA, a measure of white matter complexity, can vary markedly as a function of region of interest. Moreover, validation of these findings using neurohistological studies and replication in human samples appears warranted. PMID:20371267

  3. Reservoir description of a sand-rich submarine fan complex for a steamflood project: upper Miocene Potter sandstone, North Midway Sunset field, California

    SciTech Connect

    Shanmugam, G.; Clayton, C.A.

    1989-03-01

    Nearly 650 m of cores from the upper Miocene Potter sandstone in Mobil's Alberta/Shale property, North Midway Sunset field, California, were examined to determine depositional facies, sand-body geometry, and reservoir quality for a proposed steamflood project. The Potter represents a sand-rich submarine fan complex with braided-channel, meandering-channel, levee, and crevasse-splay facies. The braided-channel facies (gravel and coarse sand) is thick (up to 100 m), sheetlike (> 500 m wide), and highly permeable (10,000 + md). The meandering-channel facies (coarse to medium sand) is up to 20 m thick, over 400 m long, lenticular in geometry, and exhibits an upward decrease in permeability (e.g., 9000 to 500 md) related to grain size that fines upward. The levee facies (in bioturbated sand) is up to 21 m thick, shows variable geometry, and is generally low in permeability (100-1500 md). The crevasse splay (medium sand) is up to 12 m thick, sheetlike (> 300 m wide), and shows moderately high permeability (2000-8000 md). The braided-channel facies was a product of density-modified grain flows, and the remaining three facies were deposited by turbidity currents. Steam flooding of the Potter reservoir should perform extremely well because the entire reservoir is composed of relatively clean sand and the reservoir lacks both horizontal and vertical permeability barriers.

  4. GBFEL-TIE (Ground-Based Free Electron Laser Technology Experiment) sample survey on White Sands Missile Range, New Mexico: The NASA, Stallion, and Orogrande Alternatives. Final report

    SciTech Connect

    Seaman, T.J.; Doleman, W.H.

    1988-09-30

    Three locations on White Sands Missile Range, New Mexico, are under consideration as alternatives for the proposed Ground-Based Free-Electron Laser Technology Integration Experiment (GBFEL-TIE). The study conducted jointly by Prewitt and Associates, Inc., and the Office of Contract Archeology, was designed to provide input into the GBFEL-TIE Draft Environmental Impact Statement concerning the potential impact of the proposed project on cultural resources in each of the alternatives. The input consists of a series of predictions based on data gathered from two sources: (1) a cultural resource sample survey (15%) of two alternatives conducted as part of this study, and (2) from a previous survey of the third alternative. A predictive model was devleoped and applied using these data that estimated the potential impact of the GBFEL-TIE facility on the cultural resources within each alternative. The predictions indicate that the NASA alternatives, by far, the least favorable location for the facility followed by the Orogrande and Stallion Alternatives.

  5. Variation between bee communities on a sand dune complex in the Great Basin Desert, North America: Implications for sand dune conservation

    Microsoft Academic Search

    J. S. Wilson; O. J. Messinger; T. Griswold

    2009-01-01

    Sand dunes across the Mojave and Great Basin Deserts house rich bee communities. The pollination services these bees provide can be vital in maintaining the diverse, and often endemic, dune flora. These dune environments, however, are threatened by intense off-highway vehicle (OHV) use. Conservation efforts adopted by land managers often consist of setting aside a portion of a dune system

  6. SAND REPORT SAND2002xxxx

    E-print Network

    Newman, Alantha

    SAND REPORT SAND2002­xxxx Unlimited Release August 2002 Discrete Optimization Models for Protein://www.ntis.gov/ordering.htm DEPARTMENTOF ENERGY . . UNITED STATES OF AMERICA #12; SAND2002-xxxx Unlimited Release Printed August 2002

  7. White Noise Analysis: Some Applications in Complex Systems, Biophysics and Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Bernido, Christopher C.; Carpio-Bernido, M. Victoria

    2012-11-01

    The white noise calculus originated by T. Hida is presented as a powerful tool in investigating physical and social systems. Combined with Feynman's sum-over-all histories approach, we parameterize paths with memory of the past, and evaluate the corresponding probability density function. We discuss applications of this approach to problems in complex systems and biophysics. Examples in quantum mechanics with boundaries are also given where Markovian paths are considered.

  8. 2005 annual progress report: elk and bison grazing ecology in the Great Sand Dunes complex of lands

    USGS Publications Warehouse

    Schoenecker, Kate A.; Lubow, Bruce C.; Zeigenfuss, Linda C.; Mao, Julie

    2006-01-01

    Introduction: In 2000 the U.S. Congress authorized the expansion of the former Great Sand Dunes National Monument by establishing a new Great Sand Dunes National Park and Preserve in its place, and establishing the Baca National Wildlife Refuge. The establishment of Great Sand Dunes National Park and Preserve and the new Baca National Wildlife Refuge in the San Luis Valley (SLV), Colorado was one of the most significant land conservation actions in the western U.S. in recent years. The action was a result of cooperation between the National Park Service (NPS), U.S. Fish and Wildlife Service (USFWS), Bureau of Land Management (BLM), U.S. Forest Service (USDA-FS), and The Nature Conservancy (TNC). The new national park, when fully implemented, will consist of 107,265 acres, the new national preserve 41,872 acres, and the new national wildlife refuge (USFWS lands) 92,180 acres (fig. 1). The area encompassed by this designation protects a number of natural wonders and features including a unique ecosystem of natural sand dunes, the entire watershed of surface and groundwaters that are necessary to preserve and recharge the dunes and adjacent wetlands, a unique stunted forest, and other valuable riparian vegetation communities that support a host of associated wildlife and bird species. When the National Park was initially established, there were concerns about over-concentrations and impacts on native plant communities of the unhunted segments of a large and possibly growing elk (Cervus elaphus) population. This led to the designation of the Preserve as a compromise solution, where the elk could be harvested. The Preserve Unit, however, will not address all the ungulate management challenges. In order to reduce the current elk population, harvests of elk may need to be aggressive. But aggressive special hunts of elk to achieve population reductions can result in elk avoidance of certain areas or elk seeking refuge in areas where they cannot be hunted, while removals of whole herd segments and abandonment or alterations of migration routes can occur (Smith and Robbins, 1994; Boyce and others, 1991). Elk may seek refuge from hunting in the newly expanded Park Unit and TNC lands where they might over-concentrate and impact unique vegetation communities. In these sites of refugia, or preferred loafing sites, elk and bison could accelerate a decline in woody riparian shrubs and trees. This decline may also be due to changes in hydrology, climatic, or dunal processes, but ungulate herbivory might exacerbate the effects of those processes. To address the questions and needs of local resource managers, a multi-agency research project was initiated in 2005 to study the ecology, forage relations, and habitat relations of elk and bison in the Great Sand Dunes-Sangre de Cristo-Baca complex of lands. Meetings and discussions of what this research should include were started in 2001 with representatives from NPS, USFWS, TNC, the Colorado Division of Wildlife (CDOW), and USDA-FS/BLM. The final study plan was successfully funded in 2004 with research scheduled to start in 2005. The research was designed to encompass three major study elements: (1) animal movements and population dynamics, (2) vegetation and nutrient effects from ungulate herbivory, and (3) development of ecological models, using empirical data collected from the first two components, that will include estimates of elk carrying capacity and management scenarios for resource managers.

  9. Liquid Oxygen/Liquid Methane Test Summary of the RS-18 Lunar Ascent Engine at Simulated Altitude Conditions at NASA White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Melcher, John C., IV; Allred, Jennifer K.

    2009-01-01

    Tests were conducted with the RS18 rocket engine using liquid oxygen (LO2) and liquid methane (LCH4) propellants under simulated altitude conditions at NASA Johnson Space Center White Sands Test Facility (WSTF). This project is part of NASA s Propulsion and Cryogenics Advanced Development (PCAD) project. "Green" propellants, such as LO2/LCH4, offer savings in both performance and safety over equivalently sized hypergolic propellant systems in spacecraft applications such as ascent engines or service module engines. Altitude simulation was achieved using the WSTF Large Altitude Simulation System, which provided altitude conditions equivalent up to approx.120,000 ft (approx.37 km). For specific impulse calculations, engine thrust and propellant mass flow rates were measured. Propellant flow rate was measured using a coriolis-style mass-flow meter and compared with a serial turbine-style flow meter. Results showed a significant performance measurement difference during ignition startup. LO2 flow ranged from 5.9-9.5 lbm/sec (2.7-4.3 kg/sec), and LCH4 flow varied from 3.0-4.4 lbm/sec (1.4-2.0 kg/sec) during the RS-18 hot-fire test series. Thrust was measured using three load cells in parallel. Ignition was demonstrated using a gaseous oxygen/methane spark torch igniter. Data was obtained at multiple chamber pressures, and calculations were performed for specific impulse, C* combustion efficiency, and thrust vector alignment. Test objectives for the RS-18 project are 1) conduct a shakedown of the test stand for LO2/methane lunar ascent engines, 2) obtain vacuum ignition data for the torch and pyrotechnic igniters, and 3) obtain nozzle kinetics data to anchor two-dimensional kinetics codes.

  10. Infrared Camera Characterization of Bi-Propellant Reaction Control Engines during Auxiliary Propulsion Systems Tests at NASA's White Sands Test Facility in Las Cruces, New Mexico

    NASA Technical Reports Server (NTRS)

    Holleman, Elizabeth; Sharp, David; Sheller, Richard; Styron, Jason

    2007-01-01

    This paper describes the application of a FUR Systems A40M infrared (IR) digital camera for thermal monitoring of a Liquid Oxygen (LOX) and Ethanol bi-propellant Reaction Control Engine (RCE) during Auxiliary Propulsion System (APS) testing at the National Aeronautics & Space Administration's (NASA) White Sands Test Facility (WSTF) near Las Cruces, New Mexico. Typically, NASA has relied mostly on the use of ThermoCouples (TC) for this type of thermal monitoring due to the variability of constraints required to accurately map rapidly changing temperatures from ambient to glowing hot chamber material. Obtaining accurate real-time temperatures in the JR spectrum is made even more elusive by the changing emissivity of the chamber material as it begins to glow. The parameters evaluated prior to APS testing included: (1) remote operation of the A40M camera using fiber optic Firewire signal sender and receiver units; (2) operation of the camera inside a Pelco explosion proof enclosure with a germanium window; (3) remote analog signal display for real-time monitoring; (4) remote digital data acquisition of the A40M's sensor information using FUR's ThermaCAM Researcher Pro 2.8 software; and (5) overall reliability of the system. An initial characterization report was prepared after the A40M characterization tests at Marshall Space Flight Center (MSFC) to document controlled heat source comparisons to calibrated TCs. Summary IR digital data recorded from WSTF's APS testing is included within this document along with findings, lessons learned, and recommendations for further usage as a monitoring tool for the development of rocket engines.

  11. Liquid Oxygen/Liquid Methane Test Results of the RS-18 Lunar Ascent Engine at Simulated Altitude Conditions at NASA White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    Melcher, John C., IV; Allred, Jennifer K.

    2009-01-01

    Tests were conducted with the RS-18 rocket engine using liquid oxygen (LO2) and liquid methane (LCH4) propellants under simulated altitude conditions at NASA Johnson Space Center White Sands Test Facility (WSTF). This project is part of NASA's Propulsion and Cryogenics Advanced Development (PCAD) project. "Green" propellants, such as LO2/LCH4, offer savings in both performance and safety over equivalently sized hypergolic propulsion systems in spacecraft applications such as ascent engines or service module engines. Altitude simulation was achieved using the WSTF Large Altitude Simulation System, which provided altitude conditions equivalent up to 122,000 ft (37 km). For specific impulse calculations, engine thrust and propellant mass flow rates were measured. LO2 flow ranged from 5.9 - 9.5 lbm/sec (2.7 - 4.3 kg/sec), and LCH4 flow varied from 3.0 - 4.4 lbm/sec (1.4 - 2.0 kg/sec) during the RS-18 hot-fire test series. Propellant flow rate was measured using a coriolis mass-flow meter and compared with a serial turbine-style flow meter. Results showed a significant performance measurement difference during ignition startup due to two-phase flow effects. Subsequent cold-flow testing demonstrated that the propellant manifolds must be adequately flushed in order for the coriolis flow meters to give accurate data. The coriolis flow meters were later shown to provide accurate steady-state data, but the turbine flow meter data should be used in transient phases of operation. Thrust was measured using three load cells in parallel, which also provides the capability to calculate thrust vector alignment. Ignition was demonstrated using a gaseous oxygen/methane spark torch igniter. Test objectives for the RS-18 project are 1) conduct a shakedown of the test stand for LO2/methane lunar ascent engines, 2) obtain vacuum ignition data for the torch and pyrotechnic igniters, and 3) obtain nozzle kinetics data to anchor two-dimensional kinetics codes. All of these objectives were met with the RS-18 data and additional testing data from subsequent LO2/methane test programs in 2009 which included the first simulated-altitude pyrotechnic ignition demonstration of LO2/methane.

  12. Sand Storage

    USGS Multimedia Gallery

    A sand storage silo at Steamtown National Historic Site. Sand was stored in a dome on top of the engine and, as the train traveled the tracks, the sand would be sprinkled down pipes to land on the tracks in front of the wheels. This would aid the wheels in gripping the tracks, especially when the ra...

  13. Sand Stories

    NSDL National Science Digital Library

    Hilary Christensen

    The objective of this project is to use a sample of sand from a give are to tell its geologic history. Each student is given a 50 mL tube of sand labeled with the latitude and longitude of where it was found. They must then use this information along with analysis of the sand itself to tell the story of its formation.

  14. Measurements of the complex dielectric constant of sand and dust particles at 11 GHz

    NASA Astrophysics Data System (ADS)

    Al-Rizzo, Hussain M.; Al-Hafid, Hafid T.

    1988-03-01

    Measurements are reported of the refractive index (Delta-n) and loss tangent (tan delta) of dust particles in a laboratory-simulated model of dust storms, carried out at 11 GHz utilizing a confocal microwave open-cavity resonator. Four samples were used namely, sandy, silty, clayey silt, and clayey, for concentrations varying from 10-4 to 4 x 10-3 g/cu cm. The particle-size distribution (PSD) of each sample was measured by seiving along with the hydrometer technique. Dielectric-constant measurements were also conducted at bulk concentrations using the standing-wave technique for the dry samples and as a function of volumetric moisture content for up to 0.5 cu cm/cu cm. The complex dielectric constant of the dust particle material was evaluated by two approaches. In one the data for permittivities obtained over the whole range of measured concentrations were extrapolated to the particle densities of the samples. In the other a mixing formula was utilized for the determination of epsilon(s) from permittivities measured at bulk concentrations.

  15. SLOW SAND FILTRATIONSLOW SAND FILTRATION

    E-print Network

    SLOW SAND FILTRATIONSLOW SAND FILTRATION:: Timeless Technology and Recent Advances SYSTEMTREATMENT SYSTEM Source Water Collection/ Protection Filtration Treatment Distribution/ Storage PretreatmentSmall Systems Packaged Coagulation TreatmentPackaged Coagulation Treatment SystemsSystems Pressure Filtration

  16. Coordination chemistry and functionalization of white phosphorus via transition metal complexes.

    PubMed

    Peruzzini, Maurizio; Gonsalvi, Luca; Romerosa, Antonio

    2005-12-01

    The chemistry of phosphorus is nowadays rivaling that of carbon in terms of complexity and diversity. This tutorial review highlights the state-of-the-art in the field of metal-mediated activation and functionalization of white phosphorus. Particular attention is given to an illustration of the coordination abilities of the intact molecule as well as the disaggregating and reaggregating metal-mediated processes resulting in different polyphosphorus ligands from P(1) to P(12). The metal-promoted P-C and P-H bond forming processes are also reviewed showing that an ecoefficient catalytic protocol for transforming P(4) into high value organophosphorus compounds is a concrete possibility for chemical companies. This tutorial review deals with the activation and functionalization of white phosphorus in the coordination sphere of transition metal complexes. Particular attention is given to the coordination abilities of the intact molecule as well as to the disaggregating and reaggregating metal-mediated processes yielding various polyphosphorus ligands from P(1) to P(12). The metal-promoted processes for P-C and P-H bond formation are also reviewed showing that an ecoefficient catalytic protocol for transforming P(4) into high value organophosphorus compounds offers good opportunities for chemical companies. PMID:16284670

  17. Solid-state white light-emitting electrochemical cells using iridium-based cationic transition metal complexes.

    PubMed

    Su, Hai-Ching; Chen, Hsiao-Fan; Fang, Fu-Chuan; Liu, Chih-Che; Wu, Chung-Chih; Wong, Ken-Tsung; Liu, Yi-Hung; Peng, Shie-Ming

    2008-03-19

    White electroluminescent (EL) emission from single-layered solid-state light-emitting electrochemical cells (LECs) based on host-guest cationic iridium complexes has been successfully demonstrated. The devices show white EL spectra (Commission Internationale de l'Eclairage coordinates ranging from (x, y) = (0.45, 0.40) to (0.35, 0.39) at 2.9-3.3 V with high color rendering indices up to 80. Peak external quantum efficiency and peak power efficiency of the white LEC reach 4% and 7.8 lm/W, respectively. These results suggest that white LECs based on host-guest cationic transition metal complexes may be a promising alternative for solid-state lighting technologies. PMID:18302372

  18. Discovering Sand and Sand Paintings

    NSDL National Science Digital Library

    John Eichinger

    2009-05-30

    This activity blends social studies and art with math and science. First, students will explore the visible characteristics of sand, and then they will make Navajo-style sand paintings with paper, glue, and colored sand. In the process, they will hone the

  19. Sequence stratigraphy of a Pliocene delta complex deposited in an active margin setting, Etchegoin and San Joaquin gas sands, San Joaquin basin, California

    SciTech Connect

    Steward, D.C. [California State Univ., Bakersfield, CA (United States)

    1996-12-31

    Prolific gas sands of the Pliocene Etchegoin and San Joaquin formations of the southern San Joaquin basin, California, are part of a 1300-m thick succession of deltaic sediments that record the final regression of the Pacific Ocean from a tectonically active, restricted basin associated with the California transform margin. Individual field studies, lacking a regional framework and based primarily on electric log data, correlate these gas sands to the extent that individual sands maintain the same stratigraphic level within the succession. However, a high-resolution sequence stratigraphic framework, constructed from recent 3D-seismic data and detailed well log correlations on the Bakersfield Arch area of the basin, indicates that the Pliocene succession is part of a south/southwest prograding delta complex. Therefore, sands climb up-section in the landward direction and grade laterally from deep-water to shallow-water facies. Because lithofacies boundaries cross chronostratigraphic surfaces, previous interpretations of the reservoir architecture are inaccurate. This model increases predictability of reservoir facies by constraining lithofacies mapping and enables interpretation of the effects on deposition of the integrated and inter-related controls of tectonics, eustatic sea-level change, and sediment supply. With this understanding, a well-defined model of the stratal architecture of the Pliocene succession of the southern San Joaquin basin is now possible.

  20. Sequence stratigraphy of a Pliocene delta complex deposited in an active margin setting, Etchegoin and San Joaquin gas sands, San Joaquin basin, California

    SciTech Connect

    Steward, D.C. (California State Univ., Bakersfield, CA (United States))

    1996-01-01

    Prolific gas sands of the Pliocene Etchegoin and San Joaquin formations of the southern San Joaquin basin, California, are part of a 1300-m thick succession of deltaic sediments that record the final regression of the Pacific Ocean from a tectonically active, restricted basin associated with the California transform margin. Individual field studies, lacking a regional framework and based primarily on electric log data, correlate these gas sands to the extent that individual sands maintain the same stratigraphic level within the succession. However, a high-resolution sequence stratigraphic framework, constructed from recent 3D-seismic data and detailed well log correlations on the Bakersfield Arch area of the basin, indicates that the Pliocene succession is part of a south/southwest prograding delta complex. Therefore, sands climb up-section in the landward direction and grade laterally from deep-water to shallow-water facies. Because lithofacies boundaries cross chronostratigraphic surfaces, previous interpretations of the reservoir architecture are inaccurate. This model increases predictability of reservoir facies by constraining lithofacies mapping and enables interpretation of the effects on deposition of the integrated and inter-related controls of tectonics, eustatic sea-level change, and sediment supply. With this understanding, a well-defined model of the stratal architecture of the Pliocene succession of the southern San Joaquin basin is now possible.

  1. 13. SANDSORTING BUILDING, THIRD FLOOR, VIBRATING SCREENS FOR SAND SORTING, ...

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

    13. SAND-SORTING BUILDING, THIRD FLOOR, VIBRATING SCREENS FOR SAND SORTING, LOOKING SOUTHWEST - Mill "C" Complex, Sand-Sorting Building, South of Dee Bennet Road, near Illinois River, Ottawa, La Salle County, IL

  2. Sands-on Learning.

    ERIC Educational Resources Information Center

    Vandervoort, Frances S.

    1989-01-01

    Provides information for the development of a lesson which teaches students about sand, discusses facts about sands, sand studies, life in the sands, and sand activities. Includes diagrams showing the range in sand grain shape, formation of sand ripples, and sand samples from around the world. (RT)

  3. Booming Sands

    NSDL National Science Digital Library

    2007-04-19

    This video segment, adapted from NOVA scienceNOW, presents basic concepts of physics behind booming sand dunes. See how surface tension affects potential and kinetic energy and how it all works together to create sound.

  4. Diurnal patterns of blowing sand

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diurnal pattern of blowing sand results from a complex process that involves an interaction between solar heating, thermal instability, atmospheric turbulence, wind strength, and surface threshold conditions. During the day, solar heating produces thermal instability, which enhances the convect...

  5. Gas percolation through sand

    NASA Astrophysics Data System (ADS)

    Proud, W. G.

    2014-05-01

    Previous research has determined the shock properties of quartz sand. The effect of the physical processes occurring with varying moisture content and particle size were shock presented. In this study the same quartz sand, in a column is subjected to blast waves over a range of pressure. The diagnostics used are pressure sensors and high-speed photography. The effect of grain size on propagation time and the effect of moisture content are determined. Aspects of particle and liquid movement are also discussed. While the velocity of the percolation through the bed is primarily controlled by grain size the effect of moisture and liquids reveals a more complex dependence.

  6. Defrosting Sand

    NASA Technical Reports Server (NTRS)

    2005-01-01

    2 September 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a patch of frost-covered, dark sand that, at the time the picture was acquired in June 2005, had begun to defrost. The frost is carbon dioxide. Dunes and other patches of sand are usually the first polar features to develop dark spots as the frost begins to sublime away.

    Location near: 78.9oS, 80.2oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  7. SAND REPORT SAND2003-0799

    E-print Network

    Ho, Cliff

    SAND REPORT SAND2003-0799 Unlimited Release Printed March 2003 Field Demonstrations://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;3 SAND2003-0799 Unlimited Release Printed March 2003 Field Demonstrations

  8. 1. SAND DRAINING & DRYING BUILDING (RIGHT), COVERED INCLINE CONVEYOR ...

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

    1. SAND DRAINING & DRYING BUILDING (RIGHT), COVERED INCLINE CONVEYOR (LOWER RIGHT) THAT EXTENDS TO THE SAND-SORTING BUILDING, AND REMAINS OF ORIGINAL (1917) WASHING, DRAINING & DRYING BUILDING (LEFT), VIEW LOOKING WEST FROM TOP OF SAND-SORTING BUILDING - Mill "C" Complex, Sand Draining & Drying Building, South of Dee Bennet Road, near Illinois River, Ottawa, La Salle County, IL

  9. Large-eddy Simulation of Boundary Layer Flow over Desert Sand Dune Structures

    NASA Astrophysics Data System (ADS)

    Uhlrich, S.; Anderson, W.; Passalacqua, P.; Mohrig, D. C.; Kocurek, G.

    2012-12-01

    Complex spatiotemporal coupling exists between desert sand dune topography and surface layer physics of the atmospheric boundary layer (ABL). Although the interactions of individual desert sand dunes have been extensively studied, with categorical interaction mechanisms identified, the aero-mechanical coupling associated with these dune interactions remains an open problem. Large-eddy simulation (LES) is used to simulate turbulent boundary layer flow over dune structures from White Sands, NM. The dunes are resolved with an immersed boundary method (IBM). The flow-forcing (imposed pressure gradient) is varied to simulate the three common prevailing wind conditions at White Sands (southwest, southeast, and northwest, with southwest being the most common). In the present research, comparison between flow statistics (dune wall pressure distribution retrieved from the IBM) and time-difference dune elevation data are used to characterize the mechanisms responsible for erosion (stoss side) and deposition (lee side) of sand. Additionally, statistical details of time series of aerodynamic forcing at different locations on the dune face are evaluated, which may be used to deepen understanding of erosion and deposition events observed in the time-difference lidar data.

  10. Beach Sand

    NSDL National Science Digital Library

    Francis Eberle

    2005-01-01

    The purpose of this assessment probe is to elicit students' ideas about weathering, erosion, deposition, and landforms. It is designed to determine if students recognize that sand on a beach may have come from distant mountains and landforms as a result of the weathering of rock, subsequent erosion, and deposition.

  11. Ganges Chasma Sand Sheet

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    Today's sand sheet is located in the Ganges Chasma portion of Valles Marineris. As with yesterday's image, note that the dune forms are seen only at the margin and that the interior of the sand sheet at this resolution appears to completely lack dune forms.

    Image information: VIS instrument. Latitude -6.4, Longitude 310.7 East (49.3 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  12. Tar sands development

    Microsoft Academic Search

    1973-01-01

    Tar sands (also known as oil sands and bituminous sands) are sand deposits which are impregnated with dense viscous petroleum. Ultimate world reserves of bitumen in tar sands are about equal to ultimate reserves of crude oil in the U.S. However, the only tar-sand deposit of present commercial importance is in the Athabasca area of Alberta, Canada. The pioneer venture

  13. A contrast and surface code explains complex responses to black and white stimuli in V1.

    PubMed

    Zurawel, Guy; Ayzenshtat, Inbal; Zweig, Shay; Shapley, Robert; Slovin, Hamutal

    2014-10-22

    We investigated the cortical mechanisms underlying the visual perception of luminance-defined surfaces and the preference for black over white stimuli in the macaque primary visual cortex, V1. We measured V1 population responses with voltage-sensitive dye imaging in fixating monkeys that were presented with white or black squares of equal contrast around a mid-gray. Regions corresponding to the squares' edges exhibited higher activity than those corresponding to the center. Responses to black were higher than to white, surprisingly to a much greater extent in the representation of the square's center. Additionally, the square-evoked activation patterns exhibited spatial modulations along the edges and corners. A model comprised of neural mechanisms that compute local contrast, local luminance temporal modulations in the black and white directions, and cortical center-surround interactions, could explain the observed population activity patterns in detail. The model captured the weaker contribution of V1 neurons that respond to positive (white) and negative (black) luminance surfaces, and the stronger contribution of V1 neurons that respond to edge contrast. Also, the model demonstrated how the response preference for black could be explained in terms of stronger surface-related activation to negative luminance modulation. The spatial modulations along the edges were accounted for by surround suppression. Overall the results reveal the relative strength of edge contrast and surface signals in the V1 response to visual objects. PMID:25339751

  14. Defrosting Sand

    NASA Technical Reports Server (NTRS)

    2005-01-01

    19 June 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dark spots formed in carbon dioxide frost that covers the surfaces of patches of sand in the south polar region. As spring arrived this year in the martian southern hemisphere, so began the annual defrosting process. The fact that sand dunes begin to defrost earlier than other surfaces, and that the defrosting process involves the formation of spots like these, has been known since the earliest days of the MGS mission.

    Location near: 66.8oS, 15.7oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

  15. Magnetic field evolution in white dwarfs: The hall effect and complexity of the field

    NASA Technical Reports Server (NTRS)

    Muslimov, A. G.; Van Horn, H. M.; Wood, M. A.

    1995-01-01

    We calculate the evolution of the magnetic fields in white dwarfs, taking into account the Hall effect. Because this effect depends nonlinearly upon the magnetic field strength B, the time dependences of the various multipole field components are coupled. The evolution of the field is thus significantly more complicated than has been indicated by previous investigations. Our calculations employ recent white dwarf evolutionary sequences computed for stars with masses 0.4, 0.6, 0.8, and 1.0 solar mass. We show that in the presence of a strong (up to approximately 10(exp 9) G) internal toroidal magnetic field; the evolution of even the lowest order poloidal modes can be substantially changed by the Hall effect. As an example, we compute the evolution of an initially weak quadrupole component, which we take arbitrarily to be approximately 0.1%-1% of the strength of a dominant dipole field. We find that coupling provided by the Hall effect can produce growth of the ratio of the quadrupole to the dipole component of the surface value of the magnetic field strength by more than a factor of 10 over the 10(exp 9) to 10(exp 10) year cooling lifetime of the white dwarf. Some consequences of these results for the process of magnetic-field evolution in white dwarfs are briefly discussed.

  16. Magnetic field evolution in white dwarfs: The hall effect and complexity of the field

    NASA Astrophysics Data System (ADS)

    Muslimov, A. G.; van Horn, H. M.; Wood, M. A.

    1995-04-01

    We calculate the evolution of the magnetic fields in white dwarfs, taking into account the Hall effect. Because this effect depends nonlinearly upon the magnetic field strength B, the time dependences of the various multipole field components are coupled. The evolution of the field is thus significantly more complicated than has been indicated by previous investigations. Our calculations employ recent white dwarf evolutionary sequences computed for stars with masses 0.4, 0.6, 0.8, and 1.0 solar mass. We show that in the presence of a strong (up to approximately 109 G) internal toroidal magnetic field; the evolution of even the lowest order poloidal modes can be substantially changed by the Hall effect. As an example, we compute the evolution of an initially weak quadrupole component, which we take arbitrarily to be approximately 0.1%-1% of the strength of a dominant dipole field. We find that coupling provided by the Hall effect can produce growth of the ratio of the quadrupole to the dipole component of the surface value of the magnetic field strength by more than a factor of 10 over the 109 to 1010 year cooling lifetime of the white dwarf. Some consequences of these results for the process of magnetic-field evolution in white dwarfs are briefly discussed.

  17. Energy Transfer Employing Europium Complex and Blue Phosphorescent Dye and Its Application in White Organic Light-Emitting Diodes

    Microsoft Academic Search

    Yuichi Hino; Hirotake Kajii; Yutaka Ohmori

    2007-01-01

    We investigated the energy transfer of a blue phosphorescent molecule, bis[(4,6-difluorophenyl)-pyridinato-N,C2'] (picolinate) iridium(III) (FIrpic), and a red europium complex of tris(dibenzoylmethane)-mono(4,7-dimethyphenanthroline) europium(III) [Eu(dbm)3phen] doped in poly(N-vinylcarbazole) (PVK). The photoluminescence (PL) spectral intensity of a PVK:Eu(dbm)3phen film was increased by FIrpic doping. Additionally, we demonstrated white organic light-emitting devices (OLEDs) employing the energy transfer from a host to dopants, showing the

  18. White Rock

    NASA Technical Reports Server (NTRS)

    2005-01-01

    14 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a portion of the famous 'White Rock' feature in Pollack Crater in the Sinus Sabaeus region of Mars. The light-toned rock is not really white, but its light tone caught the eye of Mars geologists as far back as 1972, when it was first spotted in images acquired by Mariner 9. The light-toned materials are probably the remains of a suite of layered sediments that once spread completely across the interior of Pollack Crater. Dark materials in this image include sand dunes and large ripples.

    Location near: 8.1oS, 335.1oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  19. Northern Sand Sea

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    This VIS image was taken at 82 degrees North latitude during Northern spring. The image is completely dominated by dunes. In sand seas, it is very common for a single type of dune to occur, and for a single predominate wind to control the alignment of the dunes.

    Image information: VIS instrument. Latitude 82.2, Longitude 152.5 East (207.5 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  20. White matter lesions and cognitive performance: the role of cognitively complex leisure activity

    Microsoft Academic Search

    Jane S. Saczynski; Maria K. Jonsdottir; Sigurdur Sigurdsson; Gudny Eiriksdottir; Palmi V. Jonsson; Melissa E. Garcia; Olafur Kjartansson; Mark A. van Buchem; Vilmundur Gudnason; Lenore J. Launer

    2008-01-01

    BACKGROUND: Among persons with white matter lesions (WMLs), there is a range of cognitive function. We examine whether participation in leisure activities modifies the effect of WML load on cognitive function.\\u000aMETHODS: Data are from 2300 men and women (aged 66-92 years) participating in the population-based Age Gene\\/Environment Susceptibility-Reykjavik Study. Subcortical WML load was calculated as a weighted sum, based

  1. Design and Synthesis of Pyrimidine-Based Iridium(III) Complexes with Horizontal Orientation for Orange and White Phosphorescent OLEDs.

    PubMed

    Cui, Lin-Song; Liu, Yuan; Liu, Xiang-Yang; Jiang, Zuo-Quan; Liao, Liang-Sheng

    2015-05-27

    Two phosphorescent Ir(III) complexes Ir(ppm)2(acac) and Ir(dmppm)2(acac) were synthesized and characterized with emission ranged at 584/600 nm and high photoluminescence quantum yields (PLQYs) of 0.90/0.92, respectively. The angle-dependent PL spectra analysis reveals that the two orange iridium(III) complexes embodied horizontal orientation property. The high photoluminescence quantum yield and high horizontal dipoles ratio determine their excellent device performance. The devices based on Ir(ppm)2(acac) and Ir(dmppm)2(acac) achieved efficiencies of 26.8% and 28.2%, respectively, which can be comparable to the best orange phosphorescent devices reported in the literature. Furthermore, with the introduction of FIrpic as sky-blue emitter, phosphorescent two-element white organic light-emitting devices (OLEDs) have been realized with external quantum efficiencies (EQEs) as high as 25%, which are the highest values among the reported two-element white OLEDs. PMID:25943159

  2. White Rock

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 19 April 2002) The Science 'White Rock' is the unofficial name for this unusual landform which was first observed during the Mariner 9 mission in the early 1970's. As later analysis of additional data sets would show, White Rock is neither white nor dense rock. Its apparent brightness arises from the fact that the material surrounding it is so dark. Images from the Mars Global Surveyor MOC camera revealed dark sand dunes surrounding White Rock and on the floor of the troughs within it. Some of these dunes are just apparent in the THEMIS image. Although there was speculation that the material composing White Rock could be salts from an ancient dry lakebed, spectral data from the MGS TES instrument did not support this claim. Instead, the White Rock deposit may be the erosional remnant of a previously more continuous occurrence of air fall sediments, either volcanic ash or windblown dust. The THEMIS image offers new evidence for the idea that the original deposit covered a larger area. Approximately 10 kilometers to the southeast of the main deposit are some tiny knobs of similarly bright material preserved on the floor of a small crater. Given that the eolian erosion of the main White Rock deposit has produced isolated knobs at its edges, it is reasonable to suspect that the more distant outliers are the remnants of a once continuous deposit that stretched at least to this location. The fact that so little remains of the larger deposit suggests that the material is very easily eroded and simply blows away. The Story Fingers of hard, white rock seem to jut out like icy daggers across a moody Martian surface, but appearances can be deceiving. These bright, jagged features are neither white, nor icy, nor even hard and rocky! So what are they, and why are they so different from the surrounding terrain? Scientists know that you can't always trust what your eyes see alone. You have to use other kinds of science instruments to measure things that our eyes can't see . . . things like information about what kinds of minerals make up the landforms. Mars scientists once thought, for instance, that these unusual features might be vast hills of salt, the dried up remains of a long-ago, evaporated lake. Not so, said an instrument on the Mars Global Surveyor spacecraft, which revealed that the bright material is probably made up of volcanic ash or windblown dust instead. And talk about a cyclical 'ashes to ashes, dust to dust' story! Particles of this material fell and fell until they built up quite a sedimentary deposit, which was then only eroded away again by the wind over time, leaving the spiky terrain seen today. It looks white, but its apparent brightness arises from the fact that the surrounding material is so dark. Of course, good eyesight always helps in understanding. A camera on Mars Global Surveyor with close-up capabilities revealed that sand dunes are responsible for the smudgy dark material in the bright sediment and around it. But that's not all. The THEMIS camera on the Mars Odyssey spacecraft that took this image reveals that this ashy or dusty deposit once covered a much larger area than it does today. Look yourself for two small dots of white material on the floor of a small crater nearby (center right in this image). They preserve a record that this bright deposit once reached much farther. Since so little of it remains, you can figure that the material probably isn't very hard, and simply blows away. One thing's for sure. No one looking at this image could ever think that Mars is a boring place. With all of its bright and dark contrasts, this picture would be perfect for anyone who loves Ansel Adams and his black-and-white photography.

  3. Sand resistance of sunscreens.

    PubMed

    Caswell, Michael; Wood, Caryl; Martinez, Alexa

    2012-01-01

    Like water resistance in sunscreens, sand resistance in sunscreens is the ability of the sunscreen to retain its effectiveness while undergoing sand treatment. The influence of the type of sand on the sand resistance of sunscreens has not been described. The sand resistance of a control standard sunscreen, P2, and data on three grades of Quickrete commercial grade sand, #1961, #1962, and #1152, are described. These sands represent a fine sand, a medium sand, and an all-purpose sand. Using the methodology described in the 2007 proposed amendment of the Final Monograph (1) with one exception, we obtained an SPF of 16.5 (1.6) for the control standard, compared to the expected SPF of 16.3 (3.4). After a five-minute treatment of sand #1961, #1962, or #1151, the SPF of the control standard was 18.3 (1.6), 18.4 (2.0), and 17.5 (2.2), respectively. Thus, all three sands exhibited a similar sand-resistance response. Thus, there was no significant difference in the average SPF with and without sand. The medium grade sand, Quickrete commercial grade #1962, was preferred for sand-resistance testing because the fine sand was difficult to remove from the subject's backs and the coarse sand was unpleasant to the subjects. PMID:23193889

  4. SAND REPORT SAND2005-7937

    E-print Network

    SAND REPORT SAND2005-7937 Unlimited Release Printed January 2006 Agent-Based Control of Distributed@ntis.fedworld.gov Online order: http://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;3 SAND2005-7937 Unlimited

  5. SAND REPORT SAND2003-0112

    E-print Network

    Fuerschbach, Phillip

    SAND REPORT SAND2003-0112 Unlimited Release Printed January 2003 Cold War Context Statement Sandia://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;3 SAND2003-0112 Unlimited Release Printed January 2003 Cold War Context Statement

  6. Sand particle dislodgement in windblown sand

    NASA Astrophysics Data System (ADS)

    Bo, Tian-Li; Li, Zheng; Zheng, Xiao-Jing

    2014-12-01

    The incipient motion of sand particle from sand bed plays a very important role in the prediction of windblown sand. In this paper, we proposed a new method for predicting the incipient motion of sand particle based on wind speed fluctuation as follows, when the wind speed is larger than the critical wind speed, if the total impulse on sand particle is larger than the critical impulse, incipient motion of sand particle would take place, otherwise if not. Furthermore, from the analysis of entrainment in the rolling and lifting modes, we come to the following conclusion. When the average wind speed is smaller than the critical wind speed, if the average wind speed is used to judge the incipient motion of sand particle, one will underestimate the number of sand particles jumping from the bed, if the instantaneous wind speed is used to judge incipient motion of sand particle, one will overestimate the number of sand particles jumping from the bed; When the average wind speed is larger than the critical wind speed, either the average or the instantaneous wind speeds is used to judge the incipient motion of sand particles, one will overestimate the number of sand particles jumping from the bed.

  7. Dinural patterns of blowing sand and dust

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diurnal pattern of blowing sand results from a complex interaction between the sun, the atmosphere, and the sand surface. During the day, solar heating produces thermal instability, which enhances convective mixing of high momentum winds from the upper levels of the atmosphere to the surface la...

  8. SANDIA REPORT SAND 2011-3446

    E-print Network

    SANDIA REPORT SAND 2011- 3446 Unlimited Release Printed October 2011 Phoenix: Complex Adaptive@ntis.fedworld.gov Online order: http://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;3 SAND 2011-3446 Unlimited

  9. Complex life cycle of Pterygodermatites peromysci, a trophically transmitted parasite of the white-footed mouse (Peromyscus leucopus).

    PubMed

    Luong, Lien T; Hudson, Peter J

    2012-01-01

    The aim of this study is to experimentally verify the intermediate host of a common gastrointestinal nematode, Pterygodermatites peromysci, infecting the white-footed mouse (Peromyscus leucopus) and describe the complex life cycle. As with other nematodes in the family Rictulariidae, adult worms reside in the small intestine of the host, and infective eggs are shed into the environment where they are ingested by scavenger insects. A field survey of common nocturnal insects on the forest floors of central Pennsylvania was conducted to identify the putative intermediate host. Encysted nematode larvae were recovered from the hemocoel of three species of camel cricket, Ceuthophilus pallidipes, Ceuthophilus guttulosus, and Ceuthophilus gracilipes. The mean prevalence of infection was 11-17%, and the intensity of infection ranged from 1 to 41 cysts per cricket. Laboratory white-footed mice were infected with cysts harvested from the three species of crickets. Cysts taken from the C. pallidipes produced the highest level of infection (41%); the adult worms recovered from the mice were confirmed as P. peromysci. Laboratory infections of naive C. pallidipes with P. peromysci eggs yielded a 70% infection rate, further verifying that the cricket C. pallidipes is a suitable intermediate host for P. peromysci. We discuss the importance of identifying the intermediate host for understanding the transmission dynamics of a trophically transmitted parasite. PMID:21766236

  10. Spatial HARDI: Improved Visualization of Complex White Matter Architecture with Bayesian Spatial Regularization

    PubMed Central

    Raj, Ashish; Hess, Christopher; Mukherjee, Pratik

    2010-01-01

    Imaging of water diffusion using magnetic resonance imaging has become an important noninvasive method for probing the white matter connectivity of the human brain for scientific and clinical studies. Current methods such as diffusion tensor imaging (DTI), high angular resolution diffusion imaging (HARDI) such as q-ball imaging, and diffusion spectrum imaging (DSI), are limited by low spatial resolution, long scan times, and low signal-to-noise ratio (SNR). These methods fundamentally perform reconstruction on a voxel-by-voxel level, effectively discarding the natural coherence of the data at different points in space. This paper attempts to overcome these tradeoffs by using spatial information to constrain the reconstruction from raw diffusion MRI data, and thereby improve angular resolution and noise tolerance. Spatial constraints are specified in terms of a prior probability distribution, which is then incorporated in a Bayesian reconstruction formulation. By taking the log of the resulting posterior distribution, optimal Bayesian reconstruction is reduced to a cost minimization problem. The minimization is solved using a new iterative algorithm based on successive least squares quadratic descent. Simulation studies and in vivo results are presented which indicate significant gains in terms of higher angular resolution of diffusion orientation distribution functions, better separation of crossing fibers, and improved reconstruction SNR over the same HARDI method, spherical harmonic q-ball imaging, without spatial regularization. Preliminary data also indicate that the proposed method might be better at maintaining accurate ODFs for smaller numbers of diffusion-weighted acquisition directions (hence faster scans) compared to conventional methods. Possible impacts of this work include improved evaluation of white matter microstructural integrity in regions of crossing fibers and higher spatial and angular resolution for more accurate tractography. PMID:20670684

  11. Diurnal patterns of blowing sand

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diurnal pattern of blowing sand results from a complex process that involves the interaction between the sun, wind, and earth. During the day, solar heating produces thermal instability, which enhances the convective mixing of high momentum winds from the upper levels of the atmosphere to the s...

  12. Representation and classification of complex-shaped printed regions using white tiles

    Microsoft Academic Search

    Apostolos Antonacopoulos; R. T. Ritchings

    1995-01-01

    There is an increasingly pressing need to develop document analysis methods that are able to cope with images of documents containing printed regions of complex shapes. Contrary to the bounding-box represen- tation used in most past page segmentation and classifi- cation approaches which assume rectangular regions, there is a need for a more flexible description which also retains most of

  13. Complex response of white pines to past environmental variability increases understanding of future vulnerability.

    PubMed

    Iglesias, Virginia; Krause, Teresa R; Whitlock, Cathy

    2015-01-01

    Ecological niche models predict plant responses to climate change by circumscribing species distributions within a multivariate environmental framework. Most projections based on modern bioclimatic correlations imply that high-elevation species are likely to be extirpated from their current ranges as a result of rising growing-season temperatures in the coming decades. Paleoecological data spanning the last 15,000 years from the Greater Yellowstone region describe the response of vegetation to past climate variability and suggest that white pines, a taxon of special concern in the region, have been surprisingly resilient to high summer temperature and fire activity in the past. Moreover, the fossil record suggests that winter conditions and biotic interactions have been critical limiting variables for high-elevation conifers in the past and will likely be so in the future. This long-term perspective offers insights on species responses to a broader range of climate and associated ecosystem changes than can be observed at present and should be part of resource management and conservation planning for the future. PMID:25885810

  14. Complex Response of White Pines to Past Environmental Variability Increases Understanding of Future Vulnerability

    PubMed Central

    Iglesias, Virginia; Krause, Teresa R.; Whitlock, Cathy

    2015-01-01

    Ecological niche models predict plant responses to climate change by circumscribing species distributions within a multivariate environmental framework. Most projections based on modern bioclimatic correlations imply that high-elevation species are likely to be extirpated from their current ranges as a result of rising growing-season temperatures in the coming decades. Paleoecological data spanning the last 15,000 years from the Greater Yellowstone region describe the response of vegetation to past climate variability and suggest that white pines, a taxon of special concern in the region, have been surprisingly resilient to high summer temperature and fire activity in the past. Moreover, the fossil record suggests that winter conditions and biotic interactions have been critical limiting variables for high-elevation conifers in the past and will likely be so in the future. This long-term perspective offers insights on species responses to a broader range of climate and associated ecosystem changes than can be observed at present and should be part of resource management and conservation planning for the future. PMID:25885810

  15. Wet sand flows better than dry sand

    NASA Astrophysics Data System (ADS)

    Wagner, Christian

    2015-03-01

    Wet sand that does not contain too much water is known to be stiff enough to build sand castles or in physical words has a significant yield stress. However, we could recently show that there are quite a few conditions under which such wet sand opposes less resistant to flow than its dry counterpart. This effect might have been already known to the old Egyptians: The Ancient painting of El Bersheh at the tomb of Tehutihetep shows that there was liquid poured in front of the sledge that was used to transport heavy weight stones and statues. While archeologist have attributed this to a sacral ceremony, our data clearly show that wetting the sand ground drastically decreases the effective sliding friction coefficient. We first study the stress-strain behavior of sand with and without small amounts of liquid under steady and oscillatory shear. Using a technique to quasistatically push the sand through a tube with an enforced parabolic (Poiseuille-like) profile, we minimize the effect of avalanches and shear localization. We observe that the resistance against deformation of the wet (partially saturated) sand is much smaller than that of the dry sand, and that the latter dissipates more energy under flow. Second we show experimentally that the sliding friction on sand is greatly reduced by the addition of some--but not too much--water. The formation of capillary water bridges increases the shear modulus of the sand, which facilitates the sliding.

  16. Sexual dimorphism in white campion: complex control of carpel number is revealed by y chromosome deletions.

    PubMed Central

    Lardon, A; Georgiev, S; Aghmir, A; Le Merrer, G; Negrutiu, I

    1999-01-01

    Sexual dimorphism in the dioecious plant white campion (Silene latifolia = Melandrium album) is under the control of two main regions on the Y chromosome. One such region, encoding the gynoecium-suppressing function (GSF), is responsible for the arrest of carpel initiation in male flowers. To generate chromosomal deletions, we used pollen irradiation in male plants to produce hermaphroditic mutants (bsx mutants) in which carpel development was restored. The mutants resulted from alterations in at least two GSF chromosomal regions, one autosomal and one located on the distal half of the (p)-arm of the Y chromosome. The two mutations affected carpel development independently, each mutation showing incomplete penetrance and variegation, albeit at significantly different levels. During successive meiotic generations, a progressive increase in penetrance and a reduction in variegation levels were observed and quantified at the level of the Y-linked GSF (GSF-Y). Possible mechanisms are proposed to explain the behavior of the bsx mutations: epigenetic regulation or/and second-site mutation of modifier genes. In addition, studies on the inheritance of the hermaphroditic trait showed that, unlike wild-type Y chromosomes, deleted Y chromosomes can be transmitted through both the male and the female lines. Altogether, these findings bring experimental support, on the one hand, to the existence on the Y chromosome of genic meiotic drive function(s) and, on the other hand, to models that consider that dioecy evolved through multiple mutation events. As such, the GSF is actually a system containing more than one locus and whose primary component is located on the Y chromosome. PMID:10049933

  17. The effect of serologically defined major histocompatibility complex haplotypes on Marek's disease resistance in commercially bred White Leghorn chickens.

    PubMed

    Blankert, J J; Albers, G A; Briles, W E; Vrielink-van Ginkel, M; Groot, A J; te Winkel, G P; Tilanus, M G; van der Zijpp, A J

    1990-01-01

    In commercial pure white leghorn lines, A, B, and C, the effects on resistance against a virulent strain of Marek's disease virus were assessed for B19 and B21 haplotypes of the chicken major histocompatibility complex. B haplotypes were identified by direct hemagglutination using alloantisera raised against erythrocyte antigens. In homozygous B21 female chicks from lines A and B, mortality upon challenge with virus was 16% and 9%, respectively; in B19 chicks, mortality was 42% and 60%, respectively. Intermediate mortality was observed in heterozygous B19/B21 birds. When line A and B hens were crossed with B15/B15 or B5/B19 cocks from line C, differences between B19 and B21 were significant only in the progeny from B5/B19 sires. Therefore, it was concluded that selection for major histocompatibility complex-associated disease resistance markers may be useful only when B haplotypes complement each other in commercial line crosses and when interactions with genetic background do not severely obscure the differential haplotype effects, as are observed within pure lines. PMID:2282011

  18. A newly identified protein complex that mediates white spot syndrome virus infection via chitin-binding protein.

    PubMed

    Huang, Po-Yu; Leu, Jiann-Horng; Chen, Li-Li

    2014-08-01

    White spot syndrome virus (WSSV) is a large enveloped virus which has caused severe mortality and huge economic losses in the shrimp farming industry. The enveloped virus must be combined with the receptors of the host cell membrane by the virus envelope proteins. In the case of WSSV, binding of envelope proteins with receptors of the host cell membrane was discovered in a number of previous studies, such as VP53A and 10 other proteins with chitin-binding protein (CBP), VP28 with Penaeus monodon Rab7, VP187 with ?-integrin, and so on. WSSV envelope proteins were also considered capable of forming a protein complex dubbed an 'infectome'. In this study, the research was focused on the role of CBP in the WSSV infection process, and the relationship between CBP and the envelope proteins VP24, VP28, VP31, VP32 VP39B, VP53A and VP56. The results of the reverse transcription-PCR analyses showed that CBP existed in a variety of shrimp. The speed of WSSV infection could be slowed down by inhibiting CBP gene expression. Far-Western blot analysis and His pull-down assays were conducted, and a protein complex was found that appeared to be composed of a 'linker' protein consisting of VP31, VP32 and VP39B together with four envelope proteins, including VP24, VP28, VP53A and VP56. This protein complex was possibly another part of the infectome and the possible binding region with CBP. The findings of this study may have identified certain points for further WSSV research. PMID:24836670

  19. Wet Sand flows better than dry sand

    E-print Network

    Jorge E. Fiscina; Christian Wagner

    2007-11-19

    We investigated the yield stress and the apparent viscosity of sand with and without small amounts of liquid. By pushing the sand through a tube with an enforced Poiseuille like profile we minimize the effect of avalanches and shear localization. We find that the system starts to flow when a critical shear of the order of one particle diameter is exceeded. In contrast to common believe, we observe that the resistance against the flow of wet sand is much smaller than that of dry sand. For the dissipative flow we propose a non-equilibrium state equation for granular fluids.

  20. China Dust and Sand

    Atmospheric Science Data Center

    2013-04-16

    ... article title:  Dust and Sand Sweep Over Northeast China     View Larger Image ... these views of the dust and sand that swept over northeast China on March 10, 2004. Information on the height of the dust and an ...

  1. Mineral Sands Down Under

    NSDL National Science Digital Library

    This resource describes what mineral sands are, and discusses the heavy, dark-colored minerals that they contain (rutile, ilmenite, zircon, monazite). A map shows locations of mineral sands deposits in Australia.

  2. Bioremediation of the heavy metal complex dye Isolan Dark Blue 2SGL-01 by white rot fungus Irpex lacteus.

    PubMed

    Kalpana, Duraisamy; Shim, Jae Hong; Oh, Byung-Taek; Senthil, Kalaiselvi; Lee, Yang Soo

    2011-12-30

    The present study was conducted to evaluate the decolorization and degradation of the chromium metal complex dye Isolan Dark Blue 2SGL-01 by Irpex lacteus, a white rot lignolytic fungus. I. lacteus effectively decolorized the sulphonated reactive dye at a high concentration of 250 mg/l over a wide range of pH values of 5-9 and temperatures between 20 and 35°C. Complete (100%) decolorization occurred within 96h, and I. lacteus demonstrated resistance to the metallic dye. UV-vis spectroscopy, HPLC, GC-MS, and FT-IR analyses of the extracted metabolites confirmed that the decolorization process occurred due to degradation of the dye and not merely by adsorption. GC-MS analysis indicated the formation of 1(2H)-naphthalenone, 3,4-dihydro- and 2-naphthalenol as the main metabolite. ICP analysis demonstrated the removal of 13.49% chromium, and phytotoxicity studies using germinated seeds of Vigna radiata and Brassica juncea demonstrated the nontoxic nature of the metabolites formed during the degradation of Isolan Dark Blue 2SGL-01 dye. PMID:22071260

  3. Sand for Traction

    USGS Multimedia Gallery

    Steam engines used high-grade silica sand for traction on the rails. Sand was stored in a dome on top of the engine and, as the train traveled the tracks, the sand would be sprinkled down pipes to land on the tracks in front of the wheels. This would aid the wheels in gripping the tracks, especially...

  4. Analysis of particle motions of volcanic earthquakes at White Island, New Zealand, using multicomponent complex trace analysis method

    NASA Astrophysics Data System (ADS)

    Han, Arim; Kim, Ki Young; Jolly, Arthur D.

    2015-04-01

    To investigate particle motions of volcanos seismic waves, we applied multicomponent complex trace analysis to the non-harmonic tremor detected on August 19 and very long period (VLP) and long period (LP) events recorded on October 3, 2013 at seismic stations WIZ and WSRZ on White Island volcano in New Zealand. Seismic data of 1,000 s duration from continuous records were digitized at a 100-Hz sample rate. Since spectral ranges for the tremor and LP events were overlapped to each other, a low-pass filter with a corner frequency of 0.5 Hz was applied to the VLP event only. To generate the quadrature traces, we applied the Hilbert transform to seismic data and then we calculated instantaneous polarization attributes. To minimize the effects of rapid temporal changes, 10-s moving averages were applied to the instantaneous polarization attributes. The volcanic tremor was mainly composed of horizontally polarized waves with retrograde elliptic motions for which the phase difference between vertical and horizontal components and the reciprocal ellipticity was 9 deg and 0.2 to 0.3, respectively. The rise angle less than 4 deg indicated that the sources were located at shallow depths. The VLP event was linearly polarized with phase difference nearly constant at 0 deg, reciprocal ellipticity close to 0.1, and rise angle of 58 and 52 deg at the two seismic stations. The positive values of rise angle indicate that the VLP event was composed of the compressional waves. Using the values of rise angle, elevations, and surface locations of two seismic stations, we computed the source depth of the VLP event. The depth was estimated to be 0.9 km. The LP events had values for phase difference of 11 and 3 deg, reciprocal ellipticity of 0.2 to 0.3 and rise angle less than 5 deg. The polarization attributes and particle motions of the LP events were similar to those of the volcanic tremor.

  5. Strength and sintering effects at ejection of explosively driven sand

    NASA Astrophysics Data System (ADS)

    Resnyansky, A. D.; Weckert, S. A.

    2014-05-01

    A description of the response of sand to extreme loads is very important for the evaluation of the sand ejecta impact effects on various targets. Sand is a complex material to simulate because of its porosity where the inter-phase equilibrium is hard to achieve under transient shock wave loading. A previously developed two-phase model with strength has been implemented in CTH and applied to sand. The shock response of the sand, including the Hugoniot abnormality known from the literature for highly porous silica, is adequately described with the material model. The sand unloading effects appearing as the ejecta are observed in the present work using dynamic flash X-ray of an aluminium target plate loaded by limestone sand ejecta from the detonation of a buried high explosive charge. The CTH modelling results compared with the flash X-ray images have demonstrated good agreement, particularly, in the description of momentum transfer to the target.

  6. WHITE LUPIN NITROGEN FIXATION UNDER PHOSPHORUS DEFICIENCY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    White lupin is highly adapted to growth in a low P environment. The objective of the present study was to evaluate whether white lupin grown under P-stress has adaptations in nodulation and N2 fixation that facilitate continued functioning. Nodulated plants were grown in silica sand supplied with N-...

  7. Retrieval of sand density from hyperspectral BRDF

    NASA Astrophysics Data System (ADS)

    Bachmann, Charles M.; Abelev, Andrei; Philpot, William; Doctor, Katarina Z.; Montes, Marcos J.; Fusina, Robert; Li, Rong-Rong; van Roggen, Elena

    2014-06-01

    In past work, we have shown that density effects in hyperspectral bi-directional reflectance function (BRDF) data are consistent in laboratory goniometer data, field goniometer measurements with the NRL Goniometer for Portable Hyperspectral Earth Reflectance (GOPHER), and airborne CASI-1500 hyperspectral imagery. Density effects in granular materials have been described in radiative transfer models and are known, for example, to influence both the overall level of reflectance as well as the size of specific characteristics such as the width of the opposition effect in the BRDF. However, in mineralogically complex sands, such as coastal sands, the relative change in reflectance with density depends on the composite nature of the sand. This paper examines the use of laboratory and field hyperspectral goniometer data and their utility for retrieving sand density from airborne hyperspectral imagery. We focus on limitations of current models to describe density effects in BRDF data acquired in the field, laboratory setting, and from airborne systems.

  8. Experimental Studies on the Saltating Sand Particle Transport and Wind-Sand Interaction

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Lee, Sang Joon

    2009-11-01

    Saltation is the major transport mode of wind-blown sand particles, accounting for about 75% of total sand transport through saltation, suspension and surface creep. The complex interactions among the saltating sand particles, the particles on the surface and the turbulent flow have not been fully understood owing to lack of experimental data. Various state-of-the-art flow measurement techniques were applied to comprehensively examine three different types of natural sand in a simulated atmospheric boundary layer. Firstly, digital high-speed photography was used to capture images of the saltating sand particles at 2000 frames per second, which resolved the particle motion adjacent to the sand bed surface. Secondly, instantaneous velocities of the saltating sand particles were extracted from the high-speed particle images using the particle tracking velocimetry (PTV). The particle resultant velocity, concentration and the stream-wise mass flux were evaluated as a function of height. Finally, the velocity fields of wind and wind-blown sand particles were simultaneously measured by using the PTV and the particle imaging velocimetry (PIV), respectively. This experimental study shed new lights on the complicated saltation motion, and will be helpful in enhancing formulation of theoretical models and development of effective control measures of wind erosion.

  9. Analysis of wind-blown sand movement over transverse dunes.

    PubMed

    Jiang, Hong; Huang, Ning; Zhu, Yuanjian

    2014-01-01

    Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification. PMID:25434372

  10. Analysis of Wind-blown Sand Movement over Transverse Dunes

    PubMed Central

    Jiang, Hong; Huang, Ning; Zhu, Yuanjian

    2014-01-01

    Wind-blown sand movement often occurs in a very complicated desert environment where sand dunes and ripples are the basic forms. However, most current studies on the theoretic and numerical models of wind-blown sand movement only consider ideal conditions such as steady wind velocity, flat sand surface, etc. In fact, the windward slope gradient plays a great role in the lift-off and sand particle saltation. In this paper, we propose a numerical model for the coupling effect between wind flow and saltating sand particles to simulate wind-blown sand movement over the slope surface and use the SIMPLE algorithm to calculate wind flow and simulate sands transport by tracking sand particle trajectories. We furthermore compare the result of numerical simulation with wind tunnel experiments. These results prove that sand particles have obvious effect on wind flow, especially that over the leeward slope. This study is a preliminary study on windblown sand movement in a complex terrain, and is of significance in the control of dust storms and land desertification. PMID:25434372

  11. Reinforced sand cores

    Microsoft Academic Search

    Martin Zoldan

    2005-01-01

    Engine blocks and cylinder heads (castings) are made of aluminum or cast iron. Molten metal, poured into molds, forms the shape of engine blocks and cylinder heads. Molds create the outside of the casting and sand cores create cavities within the casting. ^ Typically, sand cores must maintain small aspect ratios to preserve structural integrity during the casting process. The

  12. White Lupin (Lupinus albus) Response to Phosphorus Stress: Evidence for Complex Regulation of LaSAP1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    White lupin (Lupinus albus) has a unique adaptation to phosphorus deficiency stress, such that a set of tightly coordinated physiological and morphological responses gives rise to the formation of cluster, or proteoid roots, structures that allow the plant to live in extremely infertile soils. The c...

  13. Effects of complex radiative and convective environments on the thermal biology of the white-crowned sparrow (Zonotrichia leucophrys gambelii).

    PubMed

    Wolf, B O; Wooden, K M; Walsberg, G E

    2000-02-01

    The energy budgets of small endotherms are profoundly affected by characteristics of the physical environment such as wind speed, air temperature and solar radiation. Among these, solar radiation represents a potentially very large heat load to small animals and may have an important influence on their thermoregulatory metabolism and heat balance. In this investigation, we examined the interactive effects of wind speed and irradiance on body temperature, thermoregulatory metabolism and heat balance in the white-crowned sparrow (Zonotrichia leucophrys gambelii). We measured changes in metabolic heat production by exposing birds to different wind speeds (0.25, 0.5, 1.0 and 2.0 m s(-1)) and irradiance combinations (<3 W m(-2) and 936+/-11 W m(-2); mean +/- s.d.) at an air temperature of 10 degrees C. Body temperature was not affected by wind speed, but was significantly higher in animals not exposed to simulated solar radiation compared with those exposed at most wind speeds. In the absence of solar radiation, metabolic heat production was strongly affected by wind speed and increased by 30 % from 122 to 159 W m(-2) as wind speed increased from 0.25 to 2.0 m s(-1). Metabolic heat production was even more strongly influenced by wind speed in the presence of simulated solar radiation and increased by 51% from 94 to 142 W m(-2) as wind speed increased from 0.25 to 2. 0 m s(-1). Solar heat gain was negatively correlated with wind speed and declined from 28 to 12 W m(-2) as wind speed increased from 0.25 to 2.0 m s(-1) and, at its maximum, equaled 11% of the radiation intercepted by the animal. The overall thermal impact of the various wind speed and irradiance combinations on the animal's heat balance was examined for each treatment. Under cold conditions, with no solar radiation present, an increase in wind speed from 0.25 to 2.0 m s(-1) was equivalent to a decrease in chamber air temperature of 12.7 degrees C. With simulated solar radiation present, a similar increase in wind speed was equivalent to a decrease in chamber air temperature of 16 degrees C. Overall, shifting environmental conditions from a wind speed of 0.25 m s(-1) and irradiance of 936 W m(-2) to a wind speed of 2.0 m s(-1) with no short-wave radiation present was equivalent to decreasing chamber air temperature by approximately 20 degrees C. The sensitivity to changes in the convective environment, combined with the complex effects of changes in irradiance levels revealed by re-analyzing data published previously, significantly complicates the task of estimating the heat balance of animals in nature. PMID:10648222

  14. 7. SAND FILTERS, CANAL TO LEFT. CONCRETE OVERFLOW AREA TO ...

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

    7. SAND FILTERS, CANAL TO LEFT. CONCRETE OVERFLOW AREA TO LEFT OF CANAL ORIGINALLY PLANNED AS A STORAGE LAKE. VIEW LOOKING DUE WEST OF HINDS COMPLEX IN BACKGROUND OF SAND FILTERS. - Hinds Pump Plant, East of Joshua Tree National Monument, 5 miles north of Route 10, Hayfield, Riverside County, CA

  15. Enhancing genetic mapping of complex genomes through the design of highly-multiplexed SNP arrays: application to the large and unsequenced genomes of white spruce and black spruce

    PubMed Central

    Pavy, Nathalie; Pelgas, Betty; Beauseigle, Stéphanie; Blais, Sylvie; Gagnon, France; Gosselin, Isabelle; Lamothe, Manuel; Isabel, Nathalie; Bousquet, Jean

    2008-01-01

    Background To explore the potential value of high-throughput genotyping assays in the analysis of large and complex genomes, we designed two highly multiplexed Illumina bead arrays using the GoldenGate SNP assay for gene mapping in white spruce (Picea glauca [Moench] Voss) and black spruce (Picea mariana [Mill.] B.S.P.). Results Each array included 768 SNPs, identified by resequencing genomic DNA from parents of each mapping population. For white spruce and black spruce, respectively, 69.2% and 77.1% of genotyped SNPs had valid GoldenGate assay scores and segregated in the mapping populations. For each of these successful SNPs, on average, valid genotyping scores were obtained for over 99% of progeny. SNP data were integrated to pre-existing ALFP, ESTP, and SSR markers to construct two individual linkage maps and a composite map for white spruce and black spruce genomes. The white spruce composite map contained 821 markers including 348 gene loci. Also, 835 markers including 328 gene loci were positioned on the black spruce composite map. In total, 215 anchor markers (mostly gene markers) were shared between the two species. Considering lineage divergence at least 10 Myr ago between the two spruces, interspecific comparison of homoeologous linkage groups revealed remarkable synteny and marker colinearity. Conclusion The design of customized highly multiplexed Illumina SNP arrays appears as an efficient procedure to enhance the mapping of expressed genes and make linkage maps more informative and powerful in such species with poorly known genomes. This genotyping approach will open new avenues for co-localizing candidate genes and QTLs, partial genome sequencing, and comparative mapping across conifers. PMID:18205909

  16. Progress report--Athabasca tar sands

    Microsoft Academic Search

    Breckenridge

    1966-01-01

    A complex now under construction by Great Canadian Oil Sands (GCOS) will produce 45,000 bbl per day of crude when it goes on stream in Sept. 1967. GCOS became the first company to receive permission to produce the giant Athabasca deposit in 1962. They also obtained a permit to construct a 266-mile long pipeline to Edmonton, where it tied into

  17. Vent of Sand Volcano

    USGS Multimedia Gallery

    Vent of sand volcano produced by liquefaction is about 4 ft across in strawberry field near Watsonville. Strip spanning vent is conduit for drip irrigation system. Furrow spacing is about 1.2 m (4 ft) on center....

  18. Hydraulic Fracturing Sand

    USGS Multimedia Gallery

    Fine-grained silica sand is mixed with chemicals and water before being pumped into rock formations to prevent the newly created artificial fractures from closing after hydraulic fracturing is completed....

  19. The Morwell interseam “sands

    Microsoft Academic Search

    C. M. Barton

    1971-01-01

    Interseam “sands” of Morwell form part of a sequence of brown?coal seams, sediments and volcanic rocks which, together, make up the Tertiary Latrobe Valley Coal Measures. A detailed investigation and computer analysis of the “sands” show that they are fluviatile deposits which accumulated within the tectonically stable Latrobe Valley Depression.On an inclusive?graphic comparative scale, particle?size analyses show that the sediments

  20. White Course White Course

    E-print Network

    Thompson, Anne

    West Campus Dr White Course Dr O rchard Rd Tower Rd H a s t i n g s R d FoxHollowRd 26 26 26 BUS 322 C12 Agricultural Engineering E5 Agricultural Science & Industries E6 All-Sports Museum D10 Almquist

  1. White Course White Course

    E-print Network

    Boyer, Elizabeth W.

    Dr Dauer Rd West Campus Dr White Course Dr O rchard Rd Tower Rd H a s t i n g s R d FoxHollowRd 26 26 C12 Agricultural Engineering E5 Agricultural Science & Industries E6 All-Sports Museum D10 Almquist

  2. Sand Sheet on Crater Floor

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

    As with yesterday's image, this dune field is located inside a crater, in this case an unnamed crater at 26 degrees North latitude. In this VIS image the dunes are coalescing into a sand sheet, note the lack of dune forms to the north of the small hills. The presence of ridges and hills in the area is affecting the dune shapes.

    Image information: VIS instrument. Latitude 26.4, Longitude 62.7 East (297.3 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  3. Assessing the Effects of Light on Differentiation and Virulence of the Plant Pathogen Botrytis cinerea: Characterization of the White Collar Complex

    PubMed Central

    Hevia, Montserrat A.; Tudzynski, Paul; Larrondo, Luis F.

    2013-01-01

    Organisms are exposed to a tough environment, where acute daily challenges, like light, can strongly affect several aspects of an individual's physiology, including pathogenesis. While several fungal models have been widely employed to understand the physiological and molecular events associated with light perception, various other agricultural-relevant fungi still remain, in terms of their responsiveness to light, in the dark. The fungus Botrytis cinerea is an aggressive pathogen able to cause disease on a wide range of plant species. Natural B. cinerea isolates exhibit a high degree of diversity in their predominant mode of reproduction. Thus, the majority of naturally occurring strains are known to reproduce asexually via conidia and sclerotia, and sexually via apothecia. Studies from the 1970?s reported on specific developmental responses to treatments with near-UV, blue, red and far-red light. To unravel the signaling machinery triggering development – and possibly also connected with virulence – we initiated the functional characterization of the transcription factor/photoreceptor BcWCL1 and its partner BcWCL2, that form the White Collar Complex (WCC) in B. cinerea. Using mutants either abolished in or exhibiting enhanced WCC signaling (overexpression of both bcwcl1 and bcwcl2), we demonstrate that the WCC is an integral part of the mentioned machinery by mediating transcriptional responses to white light and the inhibition of conidiation in response to this stimulus. Furthermore, the WCC is required for coping with excessive light, oxidative stress and also to achieve full virulence. Although several transcriptional responses are abolished in the absence of bcwcl1, the expression of some genes is still light induced and a distinct conidiation pattern in response to daily light oscillations is enhanced, revealing a complex underlying photobiology. Though overlaps with well-studied fungal systems exist, the light-associated machinery of B. cinerea appears more complex than those of Neurospora crassa and Aspergillus nidulans. PMID:24391918

  4. Sound-Producing Sand Avalanches

    NSDL National Science Digital Library

    Bretz, Michael

    This site presents an analysis of the theories and experiments done so far on sound-producing (e.g., roaring, booming) sand avalanches. Several reference articles are cited, and a link to the summary of an article, "Booming Sand", in Scientific American volume 277, number 3, is provided. An on site version of another article, "Sound Producing Sand Avalanches", in Contemporary Physics, volume 38, number 5, is also presented in three different formats: PDF, HTML, and Postscript Preprint.The other main features of this site are sound recordings of booming sand, compressed squeaking sand, and croaking sand, as well as, and images and micrographs of booming dunes.

  5. Sedimentology and reservoir potential of Matilija sandstone: an Eocene sand-rich deep-sea fan and shallow-marine complex, California

    SciTech Connect

    Link, M.H. (Cities Service Co. Research, Tulsa, OK); Welton, J.E.

    1982-10-01

    A deep-sea fan facies model for the Matilija Sandstone (southern California) regression from turbidite to shallow-marine to brackish deposits are documented. In addition, reservoir characteristics and the diagenetic history of the deep-sea fan complex is discussed. Despite thick, favorable source beds and generally good initial reservoir characteristics, the Matilija Sandstone is not a productive unit of the Ventura basin because of low reservoir permeability and porosity.

  6. Hypermedicalization in White Noise.

    PubMed

    Benson, Josef

    2014-01-24

    The Nazis hijacked Germany's medical establishment and appropriated medical language to hegemonize their ideology. In White Noise, shifting medical information stifles the public into docility. In Nazi Germany the primacy of language and medical authority magnified the importance of academic doctors. The muddling of identities caused complex insecurities and the need for psychological doubles. In White Noise, Professor Gladney is driven by professional insecurities to enact a double in Murray. Through the manipulation of language and medical overreach the U.S., exemplified in the novel White Noise, has become a hypermedicalized society where the spirit of the Hippocratic Oath has eroded. PMID:24458659

  7. Percolation of Blast Waves though Sand

    NASA Astrophysics Data System (ADS)

    Proud, William

    2013-06-01

    Previous research has concentrated on the physical processes occurring when samples of sand, of varying moisture content, were shock compressed. In this study quartz sand samples are subjected to blast waves over a range of pressure and duration. Aspects of particle movement are discussed; the global movement of a bed hundreds of particles thick is a fraction of particle width. The main diagnostics used are pressure sensors and high-speed photography. Results are presented for a range of particle sizes, aspect ratio, density and moisture content. While the velocity of the percolation through the bed is primarily controlled by density and porosity the effect of moisture reveals a more complex dependence. Previous research has concentrated on the physical processes occurring when samples of sand, of varying moisture content, were shock compressed. In this study quartz sand samples are subjected to blast waves over a range of pressure and duration. Aspects of particle movement are discussed; the global movement of a bed hundreds of particles thick is a fraction of particle width. The main diagnostics used are pressure sensors and high-speed photography. Results are presented for a range of particle sizes, aspect ratio, density and moisture content. While the velocity of the percolation through the bed is primarily controlled by density and porosity the effect of moisture reveals a more complex dependence. The ISP acknowledges the support of the Atomic Weapons Establishment and Imperial College London.

  8. Joaquim Sande Silva Francisco Rego

    E-print Network

    Paris-Sud XI, Université de

    Joaquim Sande Silva Francisco Rego Paulo Fernandes Eric Rigolot (editors) Towards Integrated Fire ­ Outcomes of the European Project Fire Paradox Joaquim Sande Silva, Francisco Rego, Paulo Fernandes and Eric

  9. Sand Hill Rd. Junipero Serra

    E-print Network

    Stanford University

    Alpine 280 101 Campus Drive Sand Hill Rd. University Palm StockFarm Junipero Serra Page Mill Oregon Floor, South Wing right next to Peet's Coffee. Directions from 280 North or South - Exit Sand Hill Rd

  10. Sand and sandstone

    SciTech Connect

    Pettijohn, F.J.; Potter, P.E.; Siever, R.

    1987-01-01

    Here is a new, second edition of a classical textbook in sedimentology, petrology, and petrography of sand and sandstones. It has been extensively revised and updated, including: new techniques and their utility; new literature; new illustrations; new, explicitly stated problems for the student; and a wider scope.

  11. Building with Sand

    ERIC Educational Resources Information Center

    Ashbrook, Peggy

    2010-01-01

    Children playing in damp sand invariably try to make a tower or a tunnel. By providing experiences with a variety of materials, alone and together, teachers set up the conditions for children to learn through their senses and ensure that a class approaches a topic with a common set of experiences to build on. Learning about the properties of…

  12. Introduction Sand sole, Psettichthys melanostictus,

    E-print Network

    67(4) 9 Introduction Sand sole, Psettichthys melanostictus, is a common nearshore pleuronectid flat- fish in the northeast Pacific Ocean.Also known as fringe sole, spotted flounder, or sand flounder catches (Kramer et al., 1995). Commercial landings of sand sole in California, Oregon, and Wash- ington

  13. Intramural Sports Sand Volleyball League

    E-print Network

    Escher, Christine

    Intramural Sports Sand Volleyball League Summer 2014 Intramural Sports Calendar of Events Summer_SCIM Sports@oregonstate.edu Free Agents Free Agent players without a teammate for the Summer Sand Volleyball Thursday, June 26th Monday, June 30th Sand Volleyball League Thursday, June 26th Tuesday, July 1st Futsal

  14. Special report: Athabasca tar sands

    Microsoft Academic Search

    W. A. Bachman; D. H. Stormont

    1967-01-01

    A synthetic crude oil is being produced from the Athabasca oil sands region of northeastern Alberta. The Athabasca operations are broken down into 3 divisions: mining, extraction of oil from the sand, and pipelining to market. The entire project, operated by Great Canadian Oil Sands, Ltd., an affiliate of Sun Oil Co., is self-sufficient except for the water supply. By-

  15. Oil sands fulfill their promise

    Microsoft Academic Search

    Chaapel

    2009-01-01

    The Great Canadian Oil Sands plant, a $300 million investment for Sun Oil Co., is the first commercial facility to wrest oil from the Alberta tar sands. Energy companies are poised to invest more than $3 billion in oil sands development in the next several years. Construction already underway, planning for projects to come, and the widening scope of oil

  16. The Uve1 Endonuclease Is Regulated by the White Collar Complex to Protect Cryptococcus neoformans from UV Damage

    PubMed Central

    Verma, Surbhi; Idnurm, Alexander

    2013-01-01

    The pathogenic fungus Cryptococcus neoformans uses the Bwc1-Bwc2 photoreceptor complex to regulate mating in response to light, virulence and ultraviolet radiation tolerance. How the complex controls these functions is unclear. Here, we identify and characterize a gene in Cryptococcus, UVE1, whose mutation leads to a UV hypersensitive phenotype. The homologous gene in fission yeast Schizosaccharomyces pombe encodes an apurinic/apyrimidinic endonuclease acting in the UVDE-dependent excision repair (UVER) pathway. C. neoformans UVE1 complements a S. pombe uvde knockout strain. UVE1 is photoregulated in a Bwc1-dependent manner in Cryptococcus, and in Neurospora crassa and Phycomyces blakesleeanus that are species that represent two other major lineages in the fungi. Overexpression of UVE1 in bwc1 mutants rescues their UV sensitivity phenotype and gel mobility shift experiments show binding of Bwc2 to the UVE1 promoter, indicating that UVE1 is a direct downstream target for the Bwc1-Bwc2 complex. Uve1-GFP fusions localize to the mitochondria. Repair of UV-induced damage to the mitochondria is delayed in the uve1 mutant strain. Thus, in C. neoformans UVE1 is a key gene regulated in response to light that is responsible for tolerance to UV stress for protection of the mitochondrial genome. PMID:24039606

  17. Hot spot computational identification: Application to the complex formed between the hen egg white lysozyme (HEL) and the antibody HyHEL-10

    NASA Astrophysics Data System (ADS)

    Moreira, I. S.; Fernandes, P. A.; Ramos, M. J.

    The definition and comprehension of the hot spots in an interface is a subject of primary interest for a variety of fields, including structure-based drug design. Therefore, to achieve an alanine mutagenesis computational approach that is at the same time accurate and predictive, capable of reproducing the experimental mutagenesis values is a major challenge in the computational biochemistry field. Antibody/protein antigen complexes provide one of the greatest models to study protein-protein recognition process because they have three fundamentally features: specificity, high complementary association and a small epitope restricted to the diminutive complementary determining regions (CDR) region, while the remainder of the antibody is largely invariant. Thus, we apply a computational mutational methodological approach to the study of the antigen-antibody complex formed between the hen egg white lysozyme (HEL) and the antibody HyHEL-10. A critical evaluation that focuses essentially on the limitations and advantages between different computational methods for hot spot determination, as well as between experimental and computational methodological approaches, is presented.

  18. Distributional patterns and an additional species of the Passiflora vitifolia complex: Amazonian species diversity due to edaphically differentiated communities

    Microsoft Academic Search

    Alwyn H. Gentry

    1981-01-01

    Field studies in Amazonian Peru show that thePassiflora vitifolia complex, a microcosm of many larger taxa, is concentrated in Amazonia with 4 ecologically separated species. One species is restricted to seasonally inundated forests, a second to non-inundated white sand soils, a third to non-inundated lateritic soils, and the fourth mostly to non-inundated alluvial soils. A new combination is formally proposed

  19. Detailed mapping of fluvial sand bodies improves perforating strategy at Kern River field

    SciTech Connect

    Kodl, E.J. (Caltex Indonesia, Bakersfield, CA (United States)); Brelih, D.A. (Texaco, Inc., Bakersfield, CA (United States))

    1991-02-01

    The producing sands of the Kern River field were deposited by the ancestral Kern River as a series of stacked, and often interconnected, sand bodies. Individual channel sands combine to create composite sand bodies that range from 5 to 100 ft in thickness and from 100 ft to as much as several miles in lateral extent. This high degree of variability in both the thickness and areal extent of the oil-bearing sands inevitably produces sands not conductive to orderly and predictable, steam displacement. These sand bodies, which alone are not capable of physically or economically supporting a steamflood, may be overlooked or inefficiently perforated. However, careful planning allows for these sands to be more fully exploited when the conditions for natural gravity drainage are optimum. In the Kern River field, this means taking advantage of oil viscosity reductions (preheating) realized when the underlying sand is being actively steamflooded. In addition to the importance of timing, detailed geologic reconstructions of individual sand channels are essential to enable selective perforating of those producers which are best able to effectively produce the sand body. An efficient and timely production program under these conditions demands a high degree of communication between the geologist and the engineer, and insures maximum productivity from sands deposited in a complex fluvial depositional environment. A field study is included.

  20. The effects of psammophilous plants on sand dune dynamics

    NASA Astrophysics Data System (ADS)

    Bel, Golan; Ashkenazy, Yosef

    2014-07-01

    Mathematical models of sand dune dynamics have considered different types of sand dune cover. However, despite the important role of psammophilous plants (plants that flourish in moving-sand environments) in dune dynamics, the incorporation of their effects into mathematical models of sand dunes remains a challenging task. Here we propose a nonlinear physical model for the role of psammophilous plants in the stabilization and destabilization of sand dunes. There are two main mechanisms by which the wind affects these plants: (i) sand drift results in the burial and exposure of plants, a process that is known to result in an enhanced growth rate, and (ii) strong winds remove shoots and rhizomes and seed them in nearby locations, enhancing their growth rate. Our model describes the temporal evolution of the fractions of surface cover of regular vegetation, biogenic soil crust, and psammophilous plants. The latter reach their optimal growth under either (i) specific sand drift or (ii) specific wind power. The model exhibits complex bifurcation diagrams and dynamics, which explain observed phenomena, and it predicts new dune stabilization scenarios. Depending on the climatological conditions, it is possible to obtain one, two, or, predicted here for the first time, three stable dune states. Our model shows that the development of the different cover types depends on the precipitation rate and the wind power and that the psammophilous plants are not always the first to grow and stabilize the dunes.

  1. Compressive behavior of fine sand.

    SciTech Connect

    Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo; Chen, Wayne (Purdue University, West Lafayette, IN)

    2010-04-01

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

  2. White Toenails

    MedlinePLUS

    ... body, causing protein to be deposited within the nail bed. A fungal infection that affects the outermost layer of the toenail may cause a bright white discoloration of the toenail. A white area close to the nail fold (the lunula) varies in size from one ...

  3. Biological Significance of Photoreceptor Photocycle Length: VIVID Photocycle Governs the Dynamic VIVID-White Collar Complex Pool Mediating Photo-adaptation and Response to Changes in Light Intensity.

    PubMed

    Dasgupta, Arko; Chen, Chen-Hui; Lee, ChangHwan; Gladfelter, Amy S; Dunlap, Jay C; Loros, Jennifer J

    2015-05-01

    Most organisms on earth sense light through the use of chromophore-bearing photoreceptive proteins with distinct and characteristic photocycle lengths, yet the biological significance of this adduct decay length is neither understood nor has been tested. In the filamentous fungus Neurospora crassa VIVID (VVD) is a critical player in the process of photoadaptation, the attenuation of light-induced responses and the ability to maintain photosensitivity in response to changing light intensities. Detailed in vitro analysis of the photochemistry of the blue light sensing, FAD binding, LOV domain of VVD has revealed residues around the site of photo-adduct formation that influence the stability of the adduct state (light state), that is, altering the photocycle length. We have examined the biological significance of VVD photocycle length to photoadaptation and report that a double substitution mutant (vvdI74VI85V), previously shown to have a very fast light to dark state reversion in vitro, shows significantly reduced interaction with the White Collar Complex (WCC) resulting in a substantial photoadaptation defect. This reduced interaction impacts photoreceptor transcription factor WHITE COLLAR-1 (WC-1) protein stability when N. crassa is exposed to light: The fast-reverting mutant VVD is unable to form a dynamic VVD-WCC pool of the size required for photoadaptation as assayed both by attenuation of gene expression and the ability to respond to increasing light intensity. Additionally, transcription of the clock gene frequency (frq) is sensitive to changing light intensity in a wild-type strain but not in the fast photo-reversion mutant indicating that the establishment of this dynamic VVD-WCC pool is essential in general photobiology and circadian biology. Thus, VVD photocycle length appears sculpted to establish a VVD-WCC reservoir of sufficient size to sustain photoadaptation while maintaining sensitivity to changing light intensity. The great diversity in photocycle kinetics among photoreceptors may be viewed as reflecting adaptive responses to specific and salient tasks required by organisms to respond to different photic environments. PMID:25978382

  4. Laboratory singing sand avalanches.

    PubMed

    Dagois-Bohy, Simon; Ngo, Sandrine; du Pont, Sylvain Courrech; Douady, Stéphane

    2010-02-01

    Some desert sand dunes have the peculiar ability to emit a loud sound up to 110 dB, with a well-defined frequency: this phenomenon, known since early travelers (Darwin, Marco Polo, etc.), has been called the song of dunes. But only in late 19th century scientific observations were made, showing three important characteristics of singing dunes: first, not all dunes sing, but all the singing dunes are composed of dry and well-sorted sand; second, this sound occurs spontaneously during avalanches on a slip face; third this is not the only way to produce sound with this sand. More recent field observations have shown that during avalanches, the sound frequency does not depend on the dune size or shape, but on the grain diameter only, and scales as the square root of g/d--with g the gravity and d the diameter of the grains--explaining why all the singing dunes in the same vicinity sing at the same frequency. We have been able to reproduce these singing avalanches in laboratory on a hard plate, which made possible to study them more accurately than on the field. Signals of accelerometers at the flowing surface of the avalanche are compared to signals of microphones placed above, and it evidences a very strong vibration of the flowing layer at the same frequency as on the field, responsible for the emission of sound. Moreover, other characteristics of the booming dunes are reproduced and analyzed, such as a threshold under which no sound is produced, or beats in the sound that appears when the flow is too large. Finally, the size of the coherence zones emitting sound has been measured and discussed. PMID:19880153

  5. Metamorphic evolution of the Rechnitz metamorphic core complex in relation to the Neogene Pannonian basin, Eastern Alps: Constraints from Ar-Ar white mica ages

    NASA Astrophysics Data System (ADS)

    Cao, Shuyun; Neubauer, Franz; Genser, Johann; Bernroider, Manfred; Friedl, Gertrude

    2015-04-01

    The exhumation of Cordilleran-type metamorphic core complexes (MCC) is generally related to largely contemporaneous collapse-type sedimentary basins (mainly halfgrabens). Here, we investigate the example of the Rechnitz MCC, which formed by Miocene orogen-parallel extension within the Neogene Pannonian basin. The Rechnitz MCC is located on the South Burgenland basement High within the western part of the Neogene Pannonian basin, with the Styrian basin in the west and the Danube basin in the east. The Rechnitz MCC is metamorphosed within greenschist facies conditions (maximum temperature of 430 °C) ideal for Ar-Ar white mica dating. For the first time, we undertook an extensive survey of 40Ar/39Ar white mica dating combined with microfabrics and electron microprobe compositional data and we compare the new data with major evolutionary stages of adjacent sedimentary basins, mainly based on re-evaluation of existing reflection seismic lines. The internal structure of the Rechnitz window is characterized by two tectonic cover nappes, a lower nappe with distal continental affinity, and an upper nappe representing the infilling of an oceanic basin. Both within greenschist facies metamorphic conditions and few blueschists were found in the northwestern part of the upper nappe. We found a number of distinct white mica age spectra: (1) A sample from the northwesternmost upper nappe yield a staircase pattern ranging from 14.8 ± 0.9 Ma to 41.5 ± 1.0 Ma. We interpret the older age is minimum age of high-pressure metamorphism and the younger age as age of overprint during extensional exhumation. (2) A number of samples from the western part, independent from positions within the nappes yield plateau ages between 20 and maximum 23 Ma and are variably affected by a younger thermal overprint between 13 and 15 Ma. (3) The eastern and lower units show plateau-like patterns with plateau ages of 17 - 19 Ma with a majority at ca. 18 Ma and a single younger outlier at ca. 16 Ma. Some samples are thermally overprinted at ca. 13 Ma. We interpret the plateau ages between 23 Ma and 17 Ma as represent peak conditions of greenschist facies metamorphism. The younger ages (ca. 18 Ma) of the 17 - 23 Ma age group coincide with the onset of subsidence and terrestrial sedimentation in the Styrian basin during Ottnagian and Karpathian and is well constrained by east down normal faults. The ages also indicate an earlier stage cooling of the western part than in the east of overprint representing evidence for an eastward migrating rolling hinge type exhumation of the Rechnitz MCC. The age of overprint centering at ca. 13 Ma correlates with last extensional motions, which are also constrained by youngest normal faults in reflection seismic lines of the Styrian basin. Together the data indicate the main stage of crustal thinning in the early Miocene between 19 and 13 Ma in response of eastward retreating subduction of the land-locked Carpathian basin.

  6. Paleoenvironment and depositional environment of Miocene Olcese Sand, Bakersfield, California

    SciTech Connect

    Olson, H.C.

    1986-04-01

    The Olcese Sand near Bakersfield, California, contains evidence of a range of paleoenvironments including nonmarine, estuarine, and outer shelf depositional settings. Foraminifera from surface and subsurface samples place the Olcese in the Saucesian and Relizian of the California benthic stages. A pumice bed in the Olcese has been dated by fission track methods at 15.5 Ma. The Olcese Sand interfingers with the underlying Freeman Silt and the overlying Round Mountain Silt. In the type area, in Round Mountain oil field, the Olcese is 300-360 m thick. The Olcese is subdivided into three environmental facies. In the Knob Hill Quadrangle, the lower Olcese consists of (1) thinly bedded to blocky white tuffaceous silt and sand, or (2) planar cross-bedded fine to coarse-grained sand with pumice pebbles lining the bedding surfaces. Fossil mollusks and skate teeth indicate a shallow marine environment for the lower Olcese. Although the Olcese is predominantly a marine unit, the middle Olcese is nonmarine, with lenses of marine deposition. The middle Olcese is well exposed in the Knob Hill, Oil Center, and Rio Bravo Ranch Quadrangles, and is characterized by fine to coarse sand with occasional gravel lenses, strong cross-bedding, and a blue-gray color. The upper Olcese is a very fine to medium-grained, marine sand that fines upward into a sandy siltstone southward toward the Kern River. Foraminifera and mollusks from outcrops in the Rio Bravo Ranch Quadrangle indicate outer shelf to estuarine environments for the upper Olcese. The varying environments in the Olcese Sand reflect slight but frequent fluctuations in water depth and can be used to interpret the basin-margin history.

  7. Fluidization Characteristics of Sand and Chopped Switchgrass Sand Mixtures

    Microsoft Academic Search

    K. N. Patil; T. J. Bowser; D. D. Bellmer; R. L. Huhnke

    A laboratory, fluidized-bed gasifier is being researched as a means to gasify feedstocks in a process to produce ethanol from biomass. Fluidization characteristics of the bed, especially minimum (Umf) and complete (Ucf) fluidization velocities, were measured because they are critical to the operation of the gasifier. Fluidization properties of sand and chopped switchgrass- sand mixtures of different particle sizes and

  8. ACULEATA HYMENOPTERA OF SAND MOUNTAIN AND BLOW SAND MOUNTAINS, NEVADA

    E-print Network

    Hanks, Lawrence M.

    ACULEATA HYMENOPTERA OF SAND MOUNTAIN AND BLOW SAND MOUNTAINS, NEVADA R. W. Rust1, L. !\\1. Hanks,l.2, and R. C. BechteJ3 ABsTRACT.- There were 198 species of aculeata Hymenoptera in 15 families on the acu leate Hymenoptera collected during the study. Over 2,000 specimens were obtained, representing 198

  9. Nuclear and mitochondrial subunits from the white shrimp Litopenaeus vannamei F 0 F 1 ATP-synthase complex: cDNA sequence, molecular modeling, and mRNA quantification of atp9 and atp6

    Microsoft Academic Search

    Adriana Muhlia-Almazan; Oliviert Martinez-Cruz; Fernando Garcia-Carreño; Rodrigo Arreola; Rogerio Sotelo-Mundo; Gloria Yepiz-Plascencia

    2008-01-01

    We studied for the first time the ATP-synthase complex from shrimp as a model to understand the basis of crustacean bioenergetics\\u000a since they are exposed to endogenous processes as molting that demand high amount of energy. We analyzed the cDNA sequence\\u000a of two subunits of the Fo sector from mitochondrial ATP-synthase in the white shrimp Litopenaeus vannamei. The nucleus encoded

  10. Legged locomotion on sand

    NASA Astrophysics Data System (ADS)

    Li, Chen; Umbanhowar, Paul; Komsuoglu, Haldun; Koditschek, Daniel; Goldman, Daniel

    2009-11-01

    To understand how and why animals modulate foot kinematics to achieve effective locomotion on granular media, we study the speed of a six-legged robot with c-shaped legs, SandBot, moving on granular media for varying volume fraction, ?, limb frequency, f, and gait timing parametersfootnotetextLi et. al, PNAS, 106, 3029, 2009. Speed is determined by step length which in turn depends on limb penetration. At low f and high ? penetration is small, step length is large, and SandBot advances with a rotary walking gait in which c-legs rotate about their centers by slipping relative to stationary grains. In the opposite extreme, grains cannot support the robot; its underside always contacts the ground and it advances slowly via thrust generated as the c-legs translate through the grains. For varied gait parameters, high speeds are only observed in a small area of parameter space. A yield stress based model predicts the speed and reveals that performance is maximized when gait parameters minimize limb acceleration and interference, and limbs utilize the solidification properties of the media.

  11. Legged locomotion on sand

    NASA Astrophysics Data System (ADS)

    Li, Chen; Umbanhowar, Paul; Komsuoglu, Haldun; Koditschek, Daniel; Goldman, Daniel

    2009-11-01

    To understand how and why animals modulate foot kinematics to achieve effective locomotion on granular media, we study the speed of a six-legged robot with c-shaped legs, SandBot, moving on granular media for varying volume fraction, ?, limb frequency, f, and gait timing parameters.footnotetextLi et. al, PNAS, 106, 3029, 2009 Speed is determined by step length which in turn depends on limb penetration. At low f and high ? penetration is small, step length is large, and SandBot advances with a rotary walking gait in which c-legs rotate about their centers by slipping relative to stationary grains. In the opposite extreme, grains cannot support the robot; its underside always contacts the ground and it advances slowly via thrust generated as the c-legs translate through the grains. For varied gait parameters, high speeds are only observed in a small area of parameter space. A yield stress based model predicts the speed and reveals that performance is maximized when gait parameters minimize limb acceleration and interference, and limbs utilize the solidification properties of the media.

  12. Zeeman tomography of magnetic white dwarfs IV. The complex field structure of the polars EF Eri, BL Hyi, and CP Tuc

    E-print Network

    K. Beuermann; F. Euchner; K. Reinsch; S. Jordan; B. T. Gaensicke

    2006-10-26

    The magnetic fields of the accreting white dwarfs (WDs) in magnetic cataclysmic variables (mCVs) determine the accretion geometries, the emission properties, and the secular evolution of these objects. We determine the structure of the surface magnetic fields of the WDs primaries in magnetic CVs using Zeeman tomography. Our study is based on orbital-phase resolved optical flux and circular polarization spectra of the polars EF Eri, BL Hyi, and CP Tuc obtained with FORS1 at the ESO VLT. An evolutionary algorithm is used to synthesize best fits to these spectra from an extensive database of pre-computed Zeeman spectra. The general approach has been described in previous papers of this series. The results achieved with simple geometries as centered or offset dipoles are not satisfactory. Significantly improved fits are obtained for multipole expansions that are truncated at degree l(max)=3 or 5 and include all tesseral and sectoral components with 0CP Tuc and the ranges of field strength covered are similar for the dipole and multipole models, but only the latter provide access to accreting matter at the right locations on the WD. The results suggest that the field geometries of the WDs in short-period mCVs are quite complex with strong contributions from multipoles higher than the dipole in spite of a typical age of the WDs in CVs in excess of 1 Gyr. It is feasible to derive the surface field structure of an accreting WD from phase-resolved low-state circular spectropolarimetry of sufficiently high signal-to-noise ratio. The fact that independent information is available on the strength and direction of the field in the accretion spot from high-state observations helps in unraveling the global field structure.

  13. Science Learning in the Sand.

    ERIC Educational Resources Information Center

    Sexton, Ursula

    1997-01-01

    Presents activities that allow students to think about the Earth in a contextual manner and become familiar with constructive and destructive processes as they relate to sand - its origins, cyclical processes, and yielding of new products. Explores the bigger idea with a developmentally appropriate study of water, rocks, sand, physical phenomena,…

  14. WASTEWATER TREATMENT OVER SAND COLUMNS

    E-print Network

    Paris-Sud XI, Université de

    93/0096 WASTEWATER TREATMENT OVER SAND COLUMNS TREATMENT YIELDS, LOCALISATION OF THE BIOMASS Domestic wastewater treatment by infiltration-percolation is a process that becomming common in France, a greater depth for desinfection purposes. KEYWORDS Wastewater treatment, Infiltration-percolation. Sand

  15. Sand and Dust on Mars

    NASA Technical Reports Server (NTRS)

    Greeley, Ronald; Haberle, Robert M.

    1991-01-01

    Mars is a planet of high scientific interest. Various studies are currently being made that involve vehicles that have landed on Mars. Because Mars is known to experience frequent wind storms, mission planners and engineers require knowledge of the physical and chemical properties of Martian windblown sand and dust, and the processes involved in the origin and evolution of sand and dust storms.

  16. Modern Formation of Isotope System ( 40k, 137 Cs 226ra, 232th) In Exogenous Conditions Water Catch Basin of The White Sea

    NASA Astrophysics Data System (ADS)

    Yudakhin, F. N.; Kiseljov, G. P.; Bazhenov, A. V.

    Water modular basin of the White sea occupies a number of geological provinces. Northern and western parts are combined archey-paleozoic complex of metamorphogenic and magmatogenic mountain rock, which is blocked sporadically by low-power tundra and taiga soils. Southern, southeast and east is combined by sedimentary Paleozoic complex ? ?zen sinecliza, partially blocked by sea deposits of last freezing, on which the tundra's, southern tundra, northern and middle taiga settle down of ground actually. The ground deposits in rivers, lakes and White sea are formed from the all variety of mountain rocks, composing the territory, and up soil horizon. We investigated a system of isotopes (40K, 137Cs226Ra, 232Th,) in soils, bottom deposits of rivers, lakes and White sea, on more than 1500 tests, that allows to consider the modern spatial formation of isotope systems in soils and bottom deposits of the region. Findings about concentration of isotopes in genetic horizons of soils show the change of isotope sy stem depending on climatic zones and reflect an isotope status of environment, which basically delivers a material for bottom deposits of rivers and White sea. For bottom deposits of rivers characteristic is the following - from the washed out sand is occurs carrying out of all radionuclides, in silt sand and ooze there is an accumulation radionuclides, including 137Cs. That the silt deposits in the rivers water catch basin of the White sea occupy the subordinated situation among bottom deposits, radionucli des are actively taken out in White sea, where they collect. As a result of modern soil destruction (natural and technogenic influence) and sediment accumulation in water basin, there is a modern migration of radioactive isotopes in horizontal and vertical directions, therefore the new isotope systems are formed. Thus in soil horizons they are not steady and change at change of a climate and biological system, and in bottom deposits they are steady and further pass to a crystal status of mountain rocks.

  17. Sand swimming lizard: sandfish

    E-print Network

    Maladen, Ryan D; Kamor, Adam; Goldman, Daniel I

    2009-01-01

    We use high-speed x-ray imaging to reveal how a small (~10cm) desert dwelling lizard, the sandfish (Scincus scincus), swims within a granular medium [1]. On the surface, the lizard uses a standard diagonal gait, but once below the surface, the organism no longer uses limbs for propulsion. Instead it propagates a large amplitude single period sinusoidal traveling wave down its body and tail to propel itself at speeds up to ~1.5 body-length/sec. Motivated by these experiments we study a numerical model of the sandfish as it swims within a validated soft sphere Molecular Dynamics granular media simulation. We use this model as a tool to understand dynamics like flow fields and forces generated as the animal swims within the granular media. [1] Maladen, R.D. and Ding, Y. and Li, C. and Goldman, D.I., Undulatory Swimming in Sand: Subsurface Locomotion of the Sandfish Lizard, Science, 325, 314, 2009

  18. Unchanging Desert Sand Dunes

    NASA Astrophysics Data System (ADS)

    Gadhiraju, S.; Banerjee, B.; Buddhiraju, K.; Shah, V.

    2013-12-01

    Deserts are one of the major landforms on earth. They occupy nearly 20% of the total land area but are relatively less studied. With the rise in human population, desert regions are being gradually occupied for settlement posing a management challenge to the concerned authorities. Unrestrained erosion is generally a feature of bare dunes. Stabilized dunes, on the other hand, do not undergo major changes in textures, and can thus facilitate the growth of vegetation. Keeping in view of the above factors, better mapping and monitoring of deserts and particularly of sand dunes is needed. Mapping dunes using field instruments is very arduous and they generate relatively sparse data. In this communication, we present a method of clustering and monitoring sand dunes through imagery captured by remote sensing sensors. Initially Radon spectrum of an area is obtained by decomposition of the image into various projections sampled at finer angular directions. Statistical features such as mode, entropy and standard deviation of Radon spectrum are used in delineation and clustering of regions with different dune orientations. These clustered boundaries are used to detect if there are any changes occurring in the dune regions. In the experiment's, remote sensing data covering various dune regions of the world are observed for possible changes in dune orientations. In all the cases, it is seen that there are no major changes in desert dune orientations. While these findings have implications for understanding of dune geomorphology and changes occurring in dune directions, they also highlight the importance of a wider study of dunes and their evolution both at regional and global scales. Results for Dataset 1 & Dataset 2 Results for Dataset 3

  19. Effects of sand sediment and vertical surfaces (AquaMats TM) on production, water quality, and microbial ecology in an intensive Litopenaeus vannamei culture system

    Microsoft Academic Search

    Delma Bratvold; Craig L. Browdy

    2001-01-01

    Growth and production of Pacific white shrimp (Litopenaeus vannamei) was examined along with water quality, and general indicators of microbial activity in replicate intensive tank cultures with no sediment, sand sediment, and sand sediment together with additional vertical surfaces (sand\\/mat). All treatments received similar feed and fertilizer input. Initial linear shrimp growth rates was relatively high (1.65 g\\/week) in all

  20. Saltation of Non-Spherical Sand Particles

    PubMed Central

    Wang, Zhengshi; Ren, Shan; Huang, Ning

    2014-01-01

    Saltation is an important geological process and the primary source of atmospheric mineral dust aerosols. Unfortunately, no studies to date have been able to precisely reproduce the saltation process because of the simplified theoretical models used. For example, sand particles in most of the existing wind sand movement models are considered to be spherical, the effects of the sand shape on the structure of the wind sand flow are rarely studied, and the effect of mid-air collision is usually neglected. In fact, sand grains are rarely round in natural environments. In this paper, we first analyzed the drag coefficients, drag forces, and starting friction wind speeds of sand grains with different shapes in the saltation process, then established a sand saltation model that considers the coupling effect between wind and the sand grains, the effect of the mid-air collision of sand grains, and the effect of the sand grain shape. Based on this model, the saltation process and sand transport rate of non-spherical sand particles were simulated. The results show that the sand shape has a significant impact on the saltation process; for the same wind speed, the sand transport rates varied for different shapes of sand grains by as much as several-fold. Therefore, sand shape is one of the important factors affecting wind-sand movement. PMID:25170614

  1. Formation of aeolian ripples and sand sorting

    E-print Network

    Edgar Manukyan; Leonid Prigozhin

    2008-12-09

    We present a continuous model capable of demonstrating some salient features of aeolian sand ripples: the realistic asymmetric ripple shape, coarsening of ripple field at the nonlinear stage of ripple growth, saturation of ripple growth for homogeneous sand, typical size segregation of sand and formation of armoring layers of coarse particles on ripple crests and windward slopes if sand is inhomogeneous.

  2. Animating Sand as a Fluid Yongning Zhu

    E-print Network

    Bridson, Robert

    Animating Sand as a Fluid by Yongning Zhu B.Sc., Peking University, 2003 A THESIS SUBMITTED;Abstract My thesis presents a physics-based simulation method for animating sand. To allow for efficiently scaling up to large volumes of sand, we abstract away the individual grains and think of the sand

  3. Steamflooding strategy for thin sands

    SciTech Connect

    Doscher, T.M.; El-Arabi, M.A.

    1983-03-01

    A description is presented of the design of a steam drive in the Chanac sand, which is only 15 to 20 feet in thickness, at a depth of approximately 1250 feet in the Edison Groves field (Kern County, California).

  4. Minimal Model for Sand Dunes

    E-print Network

    Klaus Kroy; Gerd Sauermann; Hans J. Herrmann

    2002-03-02

    We propose a minimal model for aeolian sand dunes. It combines an analytical description of the turbulent wind velocity field above the dune with a continuum saltation model that allows for saturation transients in the sand flux. The model provides a qualitative understanding of important features of real dunes, such as their longitudinal shape and aspect ratio, the formation of a slip face, the breaking of scale invariance, and the existence of a minimum dune size.

  5. Modern Graywacke-Type Sands.

    PubMed

    Hollister, C D; Heezen, B C

    1964-12-18

    A preliminary study of more than 100 deep-sea cores from abyssal plains has revealed two examples of recent muddy sands of the graywacke type which, together with the microcrystalline matrix, form a bimodal-size distribution sands have a well-sorted framework of quartz, feldspar, and rock fragments which, together with the microcrystalline matrix, form a bimodal-size distribution that is also typical of ancient graywackes. The matrix is considered to be primary. PMID:17775982

  6. Modern Graywacke-Type Sands

    Microsoft Academic Search

    Charles D. Hollister; Bruce C. Heezen

    1964-01-01

    A preliminary study of more than 100 deep-sea cores from abyssal plains has revealed two examples of recent muddy sands of the graywacke type which, together with the microcrystalline matrix, form a bimodal-size distribution sands have a well-sorted framework of quartz, feldspar, and rock fragments which, together with the microcrystalline matrix, form a bimodal-size distribution that is also typical of

  7. White Pelican

    NSDL National Science Digital Library

    The American white pelican is still considered endangered in Alberta, Canada, where the population is increasing but fewer than half of the 20 known historic nesting islands are still in use. The site provides information on this magnificent bird: habitat, general biological data, risk factors, and management. External links to Canadian parks, nonprofit groups, and other species profiles also included.

  8. White Tern

    USGS Multimedia Gallery

    The White Tern is one of eight seabird species whose population density and susceptibility to sea-level rise was studied on the French Frigate Shoals' Tern Island by biologists with the USGS Pacific Island Ecosystems Research Center's Northwestern Hawaiian Islands Climate Change Project.  ...

  9. Lipid, Fatty Acid and Energy Density Profiles of White Sharks: Insights into the Feeding Ecology and Ecophysiology of a Complex Top Predator

    PubMed Central

    Pethybridge, Heidi R.; Parrish, Christopher C.; Bruce, Barry D.; Young, Jock W.; Nichols, Peter D.

    2014-01-01

    Lipids are major sources of metabolic energy in sharks and are closely linked to environmental conditions and biological cycles, such as those related to diet, reproduction and migration. In this study, we report for the first time, the total lipid content, lipid class composition and fatty acid profiles of muscle and liver tissue of white sharks, Carcharodon carcharias, of various lengths (1.5–3.9 m), sampled at two geographically separate areas off southern and eastern Australia. Muscle tissue was low in total lipid content (<0.9% wet mass, wm) and was dominated by phospholipids (>90% of total lipid) and polyunsaturated fatty acids (34±12% of total fatty acids). In contrast, liver was high in total lipid which varied between 51–81% wm and was dominated by triacylglycerols (>93%) and monounsaturated fatty acids (36±12%). With knowledge of total lipid and dry tissue mass, we estimated the energy density of muscle (18.4±0.1 kJ g?1 dm) and liver (34.1±3.2 kJ g?1 dm), demonstrating that white sharks have very high energetic requirements. High among-individual variation in these biochemical parameters and related trophic markers were observed, but were not related to any one biological or environmental factor. Signature fatty acid profiles suggest that white sharks over the size range examined are generalist predators with fish, elasmobranchs and mammalian blubber all contributing to the diet. The ecological applications and physiological influences of lipids in white sharks are discussed along with recommendations for future research, including the use of non-lethal sampling to examine the nutritional condition, energetics and dietary relationships among and between individuals. Such knowledge is fundamental to better understand the implications of environmental perturbations on this iconic and threatened species. PMID:24871223

  10. Policy Analysis of Water Availability and Use Issues for Domestic Oil Shale and Oil Sands Development

    SciTech Connect

    Ruple, John; Keiter, Robert

    2010-12-31

    Oil shale and oil sands resources located within the intermountain west represent a vast, and as of yet, commercially untapped source of energy. Development will require water, and demand for scarce water resources stands at the front of a long list of barriers to commercialization. Water requirements and the consequences of commercial development will depend on the number, size, and location of facilities, as well as the technologies employed to develop these unconventional fuels. While the details remain unclear, the implication is not – unconventional fuel development will increase demand for water in an arid region where demand for water often exceeds supply. Water demands in excess of supplies have long been the norm in the west, and for more than a century water has been apportioned on a first-come, first-served basis. Unconventional fuel developers who have not already secured water rights stand at the back of a long line and will need to obtain water from willing water purveyors. However, uncertainty regarding the nature and extent of some senior water claims combine with indeterminate interstate river management to cast a cloud over water resource allocation and management. Quantitative and qualitative water requirements associated with Endangered Species protection also stand as barriers to significant water development, and complex water quality regulations will apply to unconventional fuel development. Legal and political decisions can give shape to an indeterminate landscape. Settlement of Northern Ute reserved rights claims would help clarify the worth of existing water rights and viability of alternative sources of supply. Interstate apportionment of the White River would go a long way towards resolving water availability in downstream Utah. And energy policy clarification will help determine the role oil shale and oil sands will play in our nation’s future.

  11. Effect of alloying yttrium on corrosion–erosion behavior of 27Cr cast white iron in different corrosive slurries

    Microsoft Academic Search

    Tiancheng Zhang; D. Y Li

    2002-01-01

    Chill cast white iron alloyed with yttrium from 0 to 1.5 wt.% was investigated with regard to its resistance to corrosion–erosion in different slurries, including tap water, NaOH (pH 12), and HNO3 (pH 3) solutions, respectively, mixed with 30 wt.% silicon sand. For comparison, sand cast 27Cr white iron was also evaluated. It was demonstrated that alloying yttrium considerably improved

  12. Sands at Gusev Crater, Mars

    NASA Astrophysics Data System (ADS)

    Cabrol, Nathalie A.; Herkenhoff, Kenneth; Knoll, Andrew H.; Farmer, Jack; Arvidson, Raymond; Grin, Edmond; Li, Ronxing; Fenton, Lori; Cohen, Barbara; Bell, James F.; Aileen Yingst, R.

    2014-05-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  13. File Classification Infrastructure Technical White Paper

    E-print Network

    Narasayya, Vivek

    File Classification Infrastructure Technical White Paper Published: May 2009 For the latest...............................................12 #12;File Classification Infrastructure -- Technical White Paper 1 Introduction Data and data of business operations on electronic data adds new dimensions of complexity to managing this vital resource

  14. Onsite Wastewater Treatment Systems: Sand Filters

    E-print Network

    Lesikar, Bruce J.

    2008-10-23

    Sand filters are beds of granular material, or sand, drained from underneath so that pretreated wastewater can be treated, collected and distributed to a land application system. This publication explains the treatment, design, operation...

  15. Onsite Wastewater Treatment Systems: Sand Filters 

    E-print Network

    Lesikar, Bruce J.

    2008-10-23

    Sand filters are beds of granular material, or sand, drained from underneath so that pretreated wastewater can be treated, collected and distributed to a land application system. This publication explains the treatment, design, operation...

  16. Loose sand habitat at the Mojave desert

    NSDL National Science Digital Library

    Katie Hale (California State University, Fullerton; Student. Biological Sciences)

    2007-01-06

    Loose sand soil lacks moisture but contains adequate moisture and nutrients for drought tolerant plants. Loose sand soil is insufficient for animals to find or make shelter. Organisms find shade and shelter under the large shrubs.

  17. Compression and Creep of Venice Lagoon Sands

    E-print Network

    Sanzeni, Alex

    A laboratory test program was conducted to evaluate the one-dimensional (1D) compression and creep properties of intact sand (and silty-sand) samples from a deep borehole at the Malamocco Inlet to the Venice Lagoon. The ...

  18. RELATIONSHIPS BETWEEN BENTHIC ORGANIC MATTER AND MACROINVERTEBRATES IN SAND SUBSTRATES

    E-print Network

    Notre Dame, University of

    RELATIONSHIPS BETWEEN BENTHIC ORGANIC MATTER AND MACROINVERTEBRATES IN SAND SUBSTRATES OF NORTHERN #12;RELATIONSHIPS BETWEEN BENTHIC ORGANIC MATTER AND MACROINVERTEBRATES IN SAND SUBSTRATES OF NORTHERN studied in sand habitats, despite the abundance of sand in many streams. These relationships were

  19. Aqueous sand-control processes conserve fuels

    Microsoft Academic Search

    Bleakley

    1974-01-01

    The shortage of diesel fuel and organic solvents is responsible, in part, for the development of new sand-control processes that show promise in field tests. Halliburton Services now has 2 sand-control techniques that use water-based solutions for preflush, spacer, and catalyst. One of these, called Hydrofix, is a sand consolidation process. The other--Hydropac--is a method for controlling sand by placing

  20. NU Intramural Sports Sand Volleyball

    E-print Network

    Sridhar, Srinivas

    in either an unsportsmanlike penalty or an ejection depending on the severity of the action. Intramural. THE GAME AND FIELD: 1. As court conditions may change, the playing area may be revised to maintain fairness will be played at the Willis Hall Sand Volleyball Court. 3. Footwear: Players may play barefoot, in socks

  1. Sand and Water Table Play

    ERIC Educational Resources Information Center

    Wallace, Ann H.; White, Mary J.; Stone, Ryan

    2010-01-01

    The authors observed preschoolers engaged at the sand and water table to determine if math could be found within their play. Wanting to understand how children interact with provided materials and what kinds of math ideas they explore during these interactions, the authors offer practical examples of how such play can promote mathematical…

  2. Geology on a Sand Budget

    ERIC Educational Resources Information Center

    Kane, Jacqueline

    2004-01-01

    Earth science teachers know how frustrating it can be to spend hundreds of dollars on three-dimensional (3-D) models of Earth's geologic features, to use the models for only a few class periods. To avoid emptying an already limited science budget, the author states that teachers can use a simple alternative to the expensive 3-D models--sand. She…

  3. White Ranch Wetlands Biological Survey

    E-print Network

    White Ranch Wetlands Biological Survey and Permanent Vegetation Monitoring Plots Prepared for: U BIOLOGICAL SURVEY AND PERMANENT VEGETATION MONITORING PLOTS Introduction In May of 1997, the U. S. Fish Weisman Lake complex (Appendix G), · explanations of CNHP imperilment ranks and federal and state status

  4. SLOW SAND FILTRATION IN THE UNITED STATES

    EPA Science Inventory

    Interest in slow sand filtration has increased dramatically in the United States in the past ten years. esearch conducted to evaluate removal of Giardia cysts and bacteria, showed that slow sand filtration is very effective in removal of these contaminants. low sand filters are m...

  5. Sand Dome on a Steam Engine

    USGS Multimedia Gallery

    Steam engines used high-grade silica sand for traction on the rails. Sand was stored in a dome on top of the engine and, as the train traveled the tracks, the sand would be sprinkled down pipes to land on the tracks in front of the wheels. This would aid the wheels in gripping the tracks, especially...

  6. ccsd00003208, Basic properties for sand automata

    E-print Network

    ccsd­00003208, version 1 ­ 4 Nov 2004 Basic properties for sand automata J. Cervelle #3; E injectivity and surjectivity for sand automata. Moreover, we begin the exploration of the dynamical behavior of sand automata proving that the property of nilpotency is undecidable. We believe that the proof

  7. Animating Sand as a Fluid Yongning Zhu

    E-print Network

    Teschner, Matthias

    Animating Sand as a Fluid Yongning Zhu University of British Columbia Robert Bridson University of British Columbia Figure 1: The Stanford bunny is simulated as water and as sand. Abstract We present a physics-based simulation method for animating sand. To allow for efficiently scaling up to large volumes

  8. Happy Birthday White House!

    ERIC Educational Resources Information Center

    Dillon, Doris; And Others

    1992-01-01

    An integrated elementary teaching package offers interesting facts about presidents and the White House. Cross-curricular activities focus on architecture, presidential birthplaces, portraits, communications, science, technology, touring the White House, children in the White House, a day in the life of the White House, and a White House birthday…

  9. The White House & Tar Sands Remarks in front of the White House on 29 August 2011.

    E-print Network

    Hansen, James E.

    a car powered by coal!? #12;This raises a question: if the Keystone XL pipeline is approved, can we make criticism: it does no good to stop the Keystone pipeline, because other pipelines will be built. Indeed. 30% of U.S. emissions is ~ 13 Keystone XL pipelines!!! By year 10 the Larson fee is equivalent to $1

  10. Australian Red Dune Sand: A Potential Martian Regolith Analog

    NASA Technical Reports Server (NTRS)

    Kuhlman, K. R.; Marshall, J.; Evans, N. D.; Luttge, A.

    2001-01-01

    To demonstrate the potential scientific and technical merits of in situ microscopy on Mars, we analyzed a possible Martian regolith analog - an acolian red dune sand from the central Australian desert (near Mt. Olga). This sand was chosen for its ubiquitous red coating and the desert environment in which is it found. Grains of this sand were analyzed using a variety of microanalytical techniques. A database of detailed studies of such terrestrial analogs would assist the study of geological and astrobiological specimens in future missions to Mars. Potential instrument concepts for in situ deployment on Mars include local electrode atom probe nanoanalysis (LEAP), vertical scanning white light interferometry (VSWLI), scanning electron microscopies, energy dispersive x-ray microanalysis (EDX), atomic force microscopy (AFM) and X-ray diffraction (XRD). While in situ deployment of these techniques is many years away, ground-based studies using these analytical techniques extend our understanding of the data obtained from instruments to be flown in the near future.

  11. Detection of naphthenic acids in fish exposed to commercial naphthenic acids and oil sands process-affected water

    Microsoft Academic Search

    R. F. Young; E. A. Orr; G. G. Goss; P. M. Fedorak

    2007-01-01

    Naphthenic acids are a complex mixture of carboxylic acids that occur naturally in petroleum. During the extraction of bitumen from the oil sands in northeastern Alberta, Canada, naphthenic acids are released into the aqueous phase and these acids become the most toxic components in the process-affected water. Although previous studies have exposed fish to naphthenic acids or oil sands process-affected

  12. Geology and resources of the Tar Sand Triangle, southeastern Utah

    SciTech Connect

    Dana, G.F.; Oliver, R.L.; Elliott, J.R.

    1984-05-01

    The Tar Sand Triangle is located in southeastern Utah between the Dirty Devil and Colorado Rivers and covers an area of about 200 square miles. The geology of the area consists of gently northwest dipping strata exposed in the box canyons and slopes of the canyonlands morphology. Strata in the area range in age from Jurassic to Permian. The majority of tar sand saturation is found in the Permian White Rim Sandstone Member of the Cutler Formation. The White Rim Sandstone Member consists of a clean, well-sorted sandstone which was deposited in a shallow marine environment. Resources were calculated from analytical data from the three coreholes drilled by the Laramie Energy Technology Center and other available data. The total in-place resources, determined from this study, are 6.3 billion barels. Previous estimates ranged from 2.9 to 16 million barrels. More coring and analyses will be necessary before a more accurate determination of resources can be attempted. 8 references, 11 figures, 7 tables.

  13. Upper Miocene Stevens sands in the Maricopa depocenter southern San Joaquin Valley, California

    SciTech Connect

    Quinn, M.J. (Chevron USA, Inc., Houston, TX (United States))

    1991-02-01

    During the late Miocene, the Maricopa depocenter was a northwest-southeast-trending trough located in the southeastern corner of the San Joaquin Valley. Uplifting granitic source terranes in the Salinian block to the southwest, the Sierra Nevada to the northeast, and the Tehachapi Mountains to the southeast shed coarse-grained quartz-rich sands into the subsiding basin in the form of deep marine turbidites. These upper Miocene turbidites are collectively referred to as the Stevens sands. Based upon studies from several oil fields within the depocenter, a generalized model has been developed for the ramp, channel, and fan deposits seen within the Stevens system. This model, and the field studies are used to examine the size, morphology, sand distribution patterns, and seismic response of these sand-rich turbidite deposits. Within the Stevens system, the majority of the hydrocarbons are found within the middle to outer parts of the turbidites fans, with post depositional compaction, uplift, and folding providing three primary types of trapping mechanism: closure due to shale compaction over sand thicks, emplacement of sands across an anticlinal axis, and updip porosity pinch-outs. Finally, the chronostratigraphy of the basin developed from the field studies is used to examine upper Miocene strike-slip movement along the San Andreas fault, uplift of the Sierra Nevada, strike-slip and normal movement along the White Wolf fault, and how these various tectonic events relate to the Stevens deposition.

  14. A europium(III) organic ternary complex applied in fabrication of near UV-based white light-emitting diodes

    Microsoft Academic Search

    H. Wang; P. He; S. Liu; J. Shi; M. Gong

    2009-01-01

    A ?-diketone, 2-acetylfluorene-4,4,4-trifluorobutane-1,3-dione (HAFTFBD), and its three europium(III) complexes, Eu(AFTFBD)3?2H2O, Eu(AFTFBD)3(TPPO)2 and Eu(AFTFBD)3phen, were designed and synthesized, where TPPO was triphenylphosphine oxide and phen was 1,10-phenanthroline. The complexes\\u000a were characterized by IR, UV-visible, photoluminescence (PL) spectroscopy and thermogravimetric analysis (TGA). The results\\u000a show that the Eu(III) complexes exhibit a high thermal stability,and wide and strong excitation bands when monitored at

  15. Drag Reduction using Superhydrophobic Sanded Teflon

    NASA Astrophysics Data System (ADS)

    Song, Dong; Daniello, Robert; Rothstein, Jonathan

    2013-11-01

    In this talk, we present a series of microfluidic experiments designed to investigate drag reduction using series of roughened Teflon surfaces. The Teflon surfaces where made superhydrophobic by imparting surface texture through sanding with sand papers with a range of grit sizes. Our previous work showed that there exists an optimal sand paper grit (240 grit) for eliminating contact angle hysteresis. We will show that a Teflon surface roughened with the same sand paper grit also maximizes the drag reduction and the slip length observed in laminar flows. Increasing or decreasing the grit size was found to reduce the drag reduction and slip length. A number of different sanding protocols were investigated including sanding preferentially in the flow direction, normal to the flow direction and with a randomized circular pattern. Of these three techniques, sanding in the flow direction was found to maximize the slip length.

  16. Rethinking White Resistance: Exploring the Discursive Practices and Psychical Negotiations of "Whiteness" in Feminist, Anti-Racist Education

    ERIC Educational Resources Information Center

    Ringrose, Jessica

    2007-01-01

    This article explores how under-theorized representations of whiteness in pedagogical literatures have informed simplistic ideas about white resistance among students. It is argued that the performance and practice of discourses of whiteness in pedagogical contexts, and the subjective, psychical and emotional complexities of engaging with…

  17. Geomorphology of desert sand dunes: A review of recent progress

    NASA Astrophysics Data System (ADS)

    Livingstone, Ian; Wiggs, Giles F. S.; Weaver, Corinne M.

    2007-02-01

    Through the 1980s and 1990s studies of the geomorphology of desert sand dunes were dominated by field studies of wind flow and sand flow over individual dunes. Alongside these there were some attempts numerically to model dune development as well as some wind tunnel studies that investigated wind flow over dunes. As developments with equipment allowed, field measurements became more sophisticated. However, by the mid-1990s it was clear that even these more complex measurements were still unable to explain the mechanisms by which sand is entrained and transported. Most importantly, the attempt to measure the stresses imposed by the wind on the sand surface proved impossible, and the use of shear (or friction) velocity as a surrogate for shear stress also failed to deliver. At the same time it has become apparent that turbulent structures in the flow may be as or more important in explaining sand flux. In a development paralleled in fluvial geomorphology, aeolian geomorphologists have attempted to measure and model turbulent structures over dunes. Progress has recently been made through the use of more complex numerical models based on computational fluid dynamics (CFD). Some of the modelling work has also suggested that notions of dune 'equilibrium' form may not be particularly helpful. This range of recent developments has not meant that field studies are now redundant. For linear dunes careful observations of individual dunes have provided important data about how the dunes develop but in this particular field some progress has been made through ground-penetrating radar images of the internal structure of the dunes. The paradigm for studies of desert dune geomorphology for several decades has been that good quality empirical data about wind flow and sand flux will enable us to understand how dunes are created and maintain their form. At least some of the difficulty in the past arose from the plethora of undirected data generated by largely inductive field studies. More recently, attention has shifted-although not completely-to modelling approaches, and very considerable progress has been made in developing models of dune development. It is clear, however, that the models will continue to require accurate field observations in order for us to be able to develop a clear understanding of desert sand dune geomorphology.

  18. Sand stresses around a wellbore

    SciTech Connect

    Risnes, R.; Bratli, R.; Horsrud, P.

    1982-12-01

    The authors have studied theoretically the stresses in a poorly consolidated sand around a cylindrical well, assuming axial symmetry. Applying theories of elasticity and plasticity on this three-dimensional (3D) model, analytical solutions for all three stress components have been worked out. The existence of a plastic zone around an uncased wellbore is confirmed, and the size of the zone is determined. When allowing an incompressible fluid to flow radially into the wellbore, a stability criterion describing the failure of the sand is found to exist. This criterion relates fluid flow forces to rock strength properties. Consideration also has been given to the stress distribution around a cased hole. It is shown that a decrease in the size of the plastic zone relative to an uncased hole occurs.

  19. Laboratory compaction of cohesionless sands 

    E-print Network

    Delphia, John Girard

    1998-01-01

    laboratory compaction methods have focused on determining the maximum This thesis follows the style and format of the Canadian Geotechnical JournaL possible dry unit weight of the soil (i. e. vibrating table compaction test, modified vibrating table... on the effectiveness of laboratory compaction. 2) Determine the effect of three different laboratory compaction procedures (i. e. Standard Proctor, Modified Proctor and the Vibrating Hammer tests) on the compaction of cohesionless sands. 3 ) Correlate the various...

  20. SAMPLING FOR SAND FLIES (DIPTERA: PSYCHODIDAE) ON RANCHES WITH HISTORIES OF VESICULAR STOMATITIS DISEASE IN NEW MEXICO AND COLORADO

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The possible presence of sand flies (Diptera: Psychodidae) among colonies of white-tailed prairie dogs, Cynomys gunnisoni Baird, was investigated on or near ranches with histories of vesicular stomatitis (VS) in domestic livestock in the mid-Rio Grande River Valley, New Mexico and West-slope region...

  1. Pediatric neurodegenerative white matter processes: leukodystrophies and beyond

    Microsoft Academic Search

    Jonathan A. Phelan; Lisa H. Lowe; Charles M. Glasier

    2008-01-01

    Pediatric neurodegenerative white matter processes are complex, numerous and result from a vast array of causes ranging from\\u000a white matter injury or inflammation to congenital metabolic disorders. When faced with a neurodegenerative white matter process\\u000a on neuroimaging, the first step for the radiologist is to determine whether the findings represent a congenital metabolic\\u000a leukodystrophy or one of various other white

  2. [Environmental toxicity of waste foundry sand].

    PubMed

    Zhang, Hai-Feng; Wang, Yu-Jue; Wang, Jin-Lin; Huang, Tian-You; Xiong, Ying

    2013-03-01

    The metal leaching characteristics and volatile organic compounds (VOCs) of five different types of waste foundry sands were analyzed with the toxicity characteristic leaching procedure (TCLP) and head space-gas chromatography (HS-GC). Microtox and soil dehydrogenase activity (DHA) tests were then used to evaluate the bio-effects of these waste sands. The results showed that due to the different metals poured and casting materials used to make the sand molds, there was significant difference among the five waste foundry sands in the compositions and concentrations of metal and organic pollutants. The concentrations of Fe in the leachates of iron and steel casting waste foundry sand exceeded the maximal allowable concentrations specified in the National Standard of Drinking Water Quality, whereas the As concentration in the leachate of aluminum casting waste foundry sand exceeded the standard. The five waste foundry sands had quite different compositions and levels of VOCs, which resulted in different levels of inhibition effects on the luminescent bacteria (30% and 95%). Additionally, the soil DHA tests suggested that metal pollutants in waste foundry sands may inhibit the soil microbial activity, whereas organics in the sands may slightly promote the microbial activity. The results of this study indicated that the waste foundry sands may pose considerable threat to the environment when improperly disposed. PMID:23745431

  3. The search for a source rock for the giant Tar Sand triangle accumulation, southeastern Utah

    USGS Publications Warehouse

    Huntoon, J.E.; Hansley, P.L.; Naeser, N.D.

    1999-01-01

    A large proportion (about 36%) of the world's oil resource is contained in accumulations of heavy oil or tar. In these large deposits of degraded oil, the oil in place represents only a fraction of what was present at the time of accumulation. In many of these deposits, the source of the oil is unknown, and the oil is thought to have migrated over long distances to the reservoirs. The Tar Sand triangle in southeastern Utah contains the largest tar sand accumulation in the United States, with 6.3 billion bbl of heavy oil estimated to be in place. The deposit is thought to have originally contained 13-16 billion bbl prior to the biodegradation, water washing, and erosion that have taken place since the middle - late Tertiary. The source of the oil is unknown. The tar is primarily contained within the Lower Permian White Rim Sandstone, but extends into permeable parts of overlying and underlying beds. Oil is interpreted to have migrated into the White Rim sometime during the Tertiary when the formation was at a depth of approximately 3500 m. This conclusion is based on integration of fluid inclusion analysis, time-temperature reconstruction, and apatite fission-track modeling for the White Rim Sandstone. Homogenization temperatures cluster around 85-90??C for primary fluid inclusions in authigenic, nonferroan dolomite in the White Rim. The fluid inclusions are associated with fluorescent oil-bearing inclusions, indicating that dolomite precipitation was coeval with oil migration. Burial reconstruction suggests that the White Rim Sandstone reached its maximum burial depth from 60 to 24 Ma, and that maximum burial was followed by unroofing from 24 to 0 Ma. Time-temperature modeling indicates that the formation experienced temperatures of 85-90??C from about 35 to 40 Ma during maximum burial. Maximum formation temperatures of about 105-110??C were reached at about 24 Ma, just prior to unroofing. Thermal modeling is used to examine the history of potential source rocks for the White Rim oil. The most attractive potential sources for White Rim oil include beds within one or more of the following formations: the Proterozoic Chuar Group, which is present in the subsurface southwest of the Tar Sand triangle; the Mississippian Delle Phosphatic Member of the Deseret Limestone and equivalent formations, the Permian Kaibab Limestone, the Sinbad Limestone Member of the Triassic Moenkopi Formation, and the Jurassic Arapien Shale, Twin Creek Limestone, and Carmel Formation, which are present west of the Tar Sand triangle; the Pennsylvanian Paradox Formation in the Paradox basin east of the Tar Sand triangle; and the Permian Park City Formation northwest of the Tar Sand triangle. Each formation has a high total organic carbon content and is distributed over a wide enough geographic area to have provided a huge volume of oil. Source beds in all of the formations reached thermal maturity at times prior to or during the time that migration into the White Rim is interpreted to have occurred. Based on all available data, the most likely source for the Tar Sand triangle appears to be the Mississippian Delle Phosphatic Member of the Deseret Limestone. Secondary migration out of the Delle is interpreted to have occurred during the Cretaceous, during Sevier thrusting. Subsequent tertiary migration into the Tar Sand triangle reservoir is interpreted to have occurred later, during middle Tertiary Laramide deformation.

  4. The White Nile sedimentary system

    NASA Astrophysics Data System (ADS)

    Garzanti, Eduardo; Andò, Sergio; Padoan, Marta; Resentini, Alberto; Vezzoli, Giovanni; Villa, Igor

    2014-05-01

    The Nile River flows for ~6700 km from south of the Equator to finally reach the Mediterranean Sea at northern subtropical latitudes (Woodward et al. 2007). This is the longest sedimentological laboratory on Earth, a unique setting in which we are investigating changes in sediment composition associated with diverse chemical and physical processes, including weathering and hydraulic sorting. The present study focuses on the southern branch of the Nile across 20° of latitude, from hyperhumid Burundi and Rwanda highlands in central Africa to Khartoum, the capital city of Sudan at the southern edge of the Sahara. Our study of the Kagera basin emphasizes the importance of weathering in soils at the source rather than during stepwise transport, and shows that the transformation of parent rocks into quartzose sand may be completed in one sedimentary cycle (Garzanti et al. 2013a). Micas and heavy minerals, less effectively diluted by recycling than main framework components, offer the best key to identify the original source-rock imprint. The different behaviour of chemical indices such as the CIA (a truer indicator of weathering) and the WIP (markedly affected by quartz dilution) helps us to distinguish strongly weathered first-cycle versus polycyclic quartz sands (Garzanti et al. 2013b). Because sediment is efficiently trapped in East African Rift lakes, the composition of Nile sediments changes repeatedly northwards across Uganda. Downstream of both Lake Kyoga and Lake Albert, quartzose sands are progressively enriched in metamorphiclastic detritus supplied from tributaries draining amphibolite-facies basements. The evolution of White Nile sediments across South Sudan, a scarcely accessible region that suffered decades of civil war, was inferred from the available information (Shukri 1950), integrated by original petrographic, heavy-mineral and geochemical data (Padoan et al. 2011). Mineralogical and isotopic signatures of Bahr-el-Jebel and Sobat sediments, derived respectively from Archean gneisses of Uganda and Neoproterozoic basements of Ethiopia, become gradually homogenized and enriched in quartz, and remain finally unchanged down to Khartoum. This suggests massive sediment dumping in the Sudd and Machar Marshes, and explains why White Nile sediment contribution to the main Nile is negligible (Garzanti et al. 2006). REFERENCES Garzanti E., Andò S., Vezzoli G., Megid A.A.A., El Kammar A., 2006. Petrology of Nile River sands (Ethiopian and Sudan): sediment budgets and erosion patterns. EPSL 252:327-341. Garzanti E., Padoan M., Setti M., Peruta L., Najman Y., Villa I.M., 2013. Weathering geochemistry and Sr-Nd fingerprints of equatorial upper Nile and Congo muds. Geochem. Geophys. Geosyst. 14:292-316. Garzanti E., Padoan M., Andò S., Resentini A., Vezzoli G., Lustrino M., 2013. Weathering and relative durability of detrital minerals in equatorial climate: sand petrology and geochemistry in the East African Rift. J.Geol. 121:547-580. Padoan M., Garzanti E., Harlavan Y., Villa I.M., 2011. Tracing Nile sediment sources by Sr and Nd isotope signatures (Uganda, Ethiopia, Sudan). Geochim. Cosmochim. Acta 75:3627-3644. Shukri N.M., 1950. The mineralogy of some Nile sediments. Quart. J. Geol. Soc. London 105:511-534. Woodward J.C., Macklin M.G., Krom M.D., Williams M.A.J. 2007. The Nile: Evolution, quaternary river environments and material fluxes. In: Large Rivers, Avijit Gupta (Ed.), Wiley, 261-292.

  5. Model studies for evaluating the neurobehavioral effects of complex hydrocarbon solvents II. Neurobehavioral effects of white spirit in rat and human.

    PubMed

    Lammers, J H C M; Emmen, H H; Muijser, H; Hoogendijk, E M G; McKee, R H; Owen, D E; Kulig, B M

    2007-07-01

    To evaluate the neurobehavioral effects of hydrocarbon solvents and to establish a working model for extrapolating animal test data to humans, studies were conducted which involved inhalation exposure of rats and humans to white spirit (WS). The specific objectives of these studies were to evaluate the behavioral effects of exposure to WS in rats and humans and to determine relationships between internal levels of exposure and behavioral effects. In both animals and volunteers, methods for assessment of similar functional effects were used to enable interspecies comparisons. A battery of tests including standardized observational measures, spontaneous motor activity assessments and learned visual discrimination performance was utilized in rat studies to evaluate acute central nervous system (CNS) depression. Groups of rats were exposed to WS at target concentrations of 0, 600, 2400 or 4800mg/m(3), 8h/day for 3 consecutive days. Blood and brain concentrations of two WS constituents; 1,2,4-trimethylbenzene (TMB) and n-decane (NDEC), were used as biomarkers of internal exposure. In a volunteer study, 12 healthy male subjects were exposed for 4h to either 57 or 570mg/m(3) WS in two test sessions spaced 7 days apart, and neurobehavioral effects were measured using a computerized neurobehavioral test battery. Blood samples were taken at the end of the exposure period to measure internal concentrations of TMB and NDEC. Results of the behavioral tests in rats indicated WS-induced changes particularly in performance and learned behavior. In humans, some subtle performance deficits were observed, particularly in attention. The behavioral effects were related to concentrations of the WS components in the central nervous system. These studies demonstrated a qualitative similarity in response between rats and humans, adding support to the view that the rodent tests can be used to predict levels of response in humans and to assist in setting occupational exposure levels for hydrocarbon solvents. PMID:17433444

  6. Solvent extraction process for tar sands

    Microsoft Academic Search

    E. W. Funk; W. G. May; J. C. Pirkle

    1982-01-01

    A solvent extraction process for tar sands is disclosed wherein a low boiling solvent having a normal boiling point of from 20* to 70* C. Is used to extract tar sands. The solvent is mixed with tar sands in a dissolution zone, the solvent:bitumen weight ratio being maintained at from about 0.5:1 to 2:1. This mixture is passed to a

  7. A branching process model for sand avalanches

    SciTech Connect

    Garcia-Pelayo, R.; Salazar, I.; Schieve, W.C. (Univ. of Texas, Austin (United States))

    1993-07-01

    An analytically solvable model for sand avalanches of noninteracting grains of sand, based on the Chapman-Kolmogorov equations, is presented. For a single avalanche, distributions of lifetimes, sizes of overflows and avalanches, and correlation functions are calculated. Some of these are exponentials, some are power laws. Spatially homogeneous distributions of avalanches are also studied. Computer simulations of avalanches of interacting grains of sand are compared to the solutions to the Chapman-Kolmogorov equations. It is found that within the range of parameters explored in the simulation, the approximation of noninteracting grains of sand is a good one. 20 refs., 4 figs.

  8. Biomass development in slow sand filters.

    PubMed

    Campos, L C; Su, M F J; Graham, N J D; Smith, S R

    2002-11-01

    Microbial biomass development in the sand and schmutzdecke layer was determined in two full-scale slow sand filters, operated with and without a light excluding cover. A standard chloroform fumigation-extraction technique was adapted to routinely measure microbial biomass concentrations in the sand beds. Sand was sampled to a depth of 10 cm and schmutzdecke was also collected at the same random positions on the uncovered filter. Interstitial microbial biomass in the uncovered sand bed increased with time and decreased with sampling depth. There was a small accumulation of sand biomass with time in the covered filter, but no relationship was apparent between biomass concentration and depth in this filter. Schmutzdecke did not develop on the covered filter and was spatially highly variable in the uncovered condition compared to the consistent patterns observed in interstitial biomass production. It is speculated that microbial biomass in the sand of uncovered filters is largely related to carbon inputs from photosynthetic activity in the schmutzdecke and involves mechanisms that spatially distribute carbon substrate from the schmutzdecke to the sand. However, total organic carbon and dissolved organic carbon removals were similar in both filters suggesting that relatively small biomass populations in covered filters are sufficient to remove residual labile carbon during advanced water treatment and little further advantage to water purification and organic carbon removal is gained by the increased production of biomass in uncovered slow sand filter beds. PMID:12418657

  9. Coupled changes in sand grain size and sand transport driven by changes in the upstream supply of sand in the Colorado River: relative importance of changes in bed-sand grain size and bed-sand area

    USGS Publications Warehouse

    Topping, D.J.; Rubin, D.M.; Melis, T.S.

    2007-01-01

    Sand transport in the Colorado River in Marble and Grand canyons was naturally limited by the upstream supply of sand. Prior to the 1963 closure of Glen Canyon Dam, the river exhibited the following four effects of sand supply limitation: (1) hysteresis in sediment concentration, (2) hysteresis in sediment grain size coupled to the hysteresis in sediment concentration, (3) production of inversely graded flood deposits, and (4) development or modification of a lag between the time of a flood peak and the time of either maximum or minimum (depending on reach geometry) bed elevation. Construction and operation of the dam has enhanced the degree to which the first two of these four effects are evident, and has not affected the degree to which the last two effects of sand supply limitation are evident in the Colorado River in Marble and Grand canyons. The first three of the effects involve coupled changes in suspended-sand concentration and grain size that are controlled by changes in the upstream supply of sand. During tributary floods, sand on the bed of the Colorado River fines; this causes the suspended sand to fine and the suspended-sand concentration to increase, even when the discharge of water remains constant. Subsequently, the bed is winnowed of finer sand, the suspended sand coarsens, and the suspended-sand concentration decreases independently of discharge. Also associated with these changes in sand supply are changes in the fraction of the bed that is covered by sand. Thus, suspended-sand concentration in the Colorado River is likely regulated by both changes in the bed-sand grain size and changes in the bed-sand area. A physically based flow and suspended-sediment transport model is developed, tested, and applied to data from the Colorado River to evaluate the relative importance of changes in the bed-sand grain size and changes in the bed-sand area in regulating suspended-sand concentration. Although the model was developed using approximations for steady, uniform flow, and other simplifications that are not met in the Colorado River, the results nevertheless support the idea that changes in bed-sand grain size are much more important than changes in bed-sand area in regulating the concentration of suspended sand.

  10. Investigating Sand on the Coast of Oregon and Washington.

    ERIC Educational Resources Information Center

    Komar, Paul D.

    2002-01-01

    Describes factors affecting sand composition and distribution along coastlines. Uses variations in sand types along the Oregon coast to illustrate the influences of sand grain density, wave action, and headlands on sand movements. Describes the seasonal movement of sand across beaches. (DLH)

  11. Inflammatory and genotoxic effects of sanding dust generated from nanoparticle-containing paints and lacquers.

    PubMed

    Saber, Anne Thoustrup; Koponen, Ismo Kalevi; Jensen, Keld Alstrup; Jacobsen, Nicklas Raun; Mikkelsen, Lone; Møller, Peter; Loft, Steffen; Vogel, Ulla; Wallin, Håkan

    2012-11-01

    Nanoparticles are increasingly used in paints and lacquers. Little is known of the toxicity of nanoparticles incorporated in complex matrices and released during different phases of the life cycle. DNA damaging activity and inflammogenicity of sanding dust sampled during standardised sanding of boards painted with paints with and without nanoparticles were determined 24 h after intratracheal instillation of a single dose of 54 ?g in mice. Dusts from nanoparticle-containing paints and lacquers did not generate pulmonary inflammation or oxidative stress. Sanding dust from both the nanoparticle-containing and the conventional lacquer and the outdoor acrylic-based reference paint increased the level of DNA strand breaks in bronchoalveolar fluid cells. In conclusion, addition of nanoparticles to paint or lacquers did not increase the potential of sanding dust for causing inflammation, oxidative stress or DNA damage, suggesting that the paint/lacquer matrix is more important as determinant of DNA damage than the nanomaterial. PMID:21995293

  12. technology offer SandTES -High Temperature Sand Thermal Energy Storage

    E-print Network

    Szmolyan, Peter

    technology offer SandTES - High Temperature Sand Thermal Energy Storage key words: High Temperature together with Dr. Eisl of ENRAG GmbH. Background Thermal energy storage (TES) systems are essential Energy Storage | Fluidized Bed | Sand | The invention consists of a fluidized bed with internal heat

  13. [Spatial distribution patterns of dry sand layer on windward slope of dunes in Horqin Sand Land].

    PubMed

    Zong, Qin; Lamusa, A; Luo, Yong-Ming; Niu, Cun-Yang; Chen, Xue-Feng; Wang, Hai-Yang

    2012-04-01

    An observation was conducted on the thickness of dry sand layer on the windward slope of mobile and fixed dunes in west Horqin Sand Land, with the spatial distribution of the dry sand layer analyzed. Most of the dry sand layer had a thickness of 5-15 cm, and 92.0% and 98.6% of the mobile and fixed dunes had the dry sand layer with this thickness, respectively. Sand-fixing plants affected the thickness and the spatial distribution of the dry sand layer. There was an obvious spatial difference in the thickness of the dry sand layer on mobile dunes, being much thicker in the upper west areas while much thinner in the lower east areas. The thickness of the dry sand layer varied from 0 to 40 cm, with an average of 9.58 +/- 3.95 cm, and the CV was 41%. The variogram of the spatial distribution of dry sand layer on mobile dunes was expressed as spherical model, with a moderate spatial correlation. In contrast, the thickness of dry sand layer on fixed dunes showed obvious homogeneity, and had less spatial difference. The thickness of the dry sand layer ranged from 0 to 20 cm, with an average of 10.91 +/- 1.70 cm, and the CV was only 16%. PMID:22803448

  14. Theoretical prediction of liftoff angular velocity distributions of sand particles in windblown sand flux

    Microsoft Academic Search

    Xiaojing Zheng; Li Xie; Xue-Yong Zou

    2006-01-01

    The liftoff angular velocities, including the rebound ones and the ejected ones, of sand particles in a windblown sand flux have a significant influence on the saltation trajectories and the transport flux and so on. However, they are not easy to determine actually both in field and in a wind tunnel, especially when the sand particles are small and the

  15. Stream/aquifer interactions at Great Sand Dunes National Monument, Colorado: influences on interdunal wetland disappearance

    NASA Astrophysics Data System (ADS)

    Wurster, Frederic C.; Cooper, David J.; Sanford, William E.

    2003-02-01

    Between 1937 and 1995 a complex of more than 100 interdunal wetlands disappeared from Great Sand Dunes National Monument, Colorado. We investigated three hypotheses that could explain wetland disappearance: (1) dune movement during a severe drought in the 1950s buried the wetlands, (2) agriculture related ground water pumping lowered the regional water table, and (3) changes in local hydrologic processes led to wetland loss. We used regional stream flow records, ground water level measurements, natural stable isotope analyses, soil stratigraphy, buried seed banks, and ground water modeling to address these hypotheses. Hydrologic data and stable isotope analyses illustrated the interaction between Sand Creek, a nearby stream, and the unconfined aquifer in the area where wetlands occurred. When the intermittent Sand Creek flows, seepage through its bed creates a large ground water mound under the creek. The seasonal development and dispersion of this mound propagates pressure waves through the aquifer that influence ground water levels up to 2 km from Sand Creek. Our data suggest the primary factors contributing to wetland disappearance were recent climatic fluctuations and incision of the Sand Creek channel. Below average stream flow between 1950 and 1980 reduced the duration of Sand Creek flow across the dune complex, minimizing ground water mound development. Consequently, the water table in the unconfined aquifer dropped ˜1.0 m and interdunal wetlands dried up. Twentieth Century incision of Sand Creek's channel reduced ground water mound height ˜2.5 m, decreasing seasonal water table fluctuations at interdunal wetlands and contributing to the overall water table decline. Long-term wet and dry cycles affect the water table elevation more than channel incision, leading us to conclude that many interdunal wetlands are ephemeral features. Wetland area is maximized during consecutive years of above average Sand Creek discharge and minimized as the water table drops during dry periods.

  16. 8? x 10? black and white photographic print made from ...

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

    8? x 10? black and white photographic print made from original 1933, 8? x 10? black and white photographic negative. New 4? x 5? archival negative made from print. Original photographer unknown. Original 8? x 10? negative located in the files of the New Orleans Public Belt Railroad administrative offices at 5100 Jefferson Highway, Jefferson, LA 70123. OCTOBER 17, 1933 PHOTOGRAPH NO. 57A OF CONTRACT NO. 3 SHOWING MAIN BRIDGE PLACING OF SAND FILL AT PIER NO. II. - Huey P. Long Bridge, Spanning Mississippi River approximately midway between nine & twelve mile points upstream from & west of New Orleans, Jefferson, Jefferson Parish, LA

  17. 8? x 10? black and white photographic print made from ...

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

    8? x 10? black and white photographic print made from original 1933, 8? x 10? black and white photographic negative. New 4? x 5? archival negative made from print. Original photographer unknown. Original 8? x 10? negative located in the files of the New Orleans Public Belt Railroad administrative offices at 5100 Jefferson Highway, Jefferson, LA 70123. SEPTEMBER 25, 1933 PHOTOGRAPH NO. 41 OF CONTRACT NO. 3 SHOWING MAIN BRIDGE PLACING SAND ISLAND FILL AT PIER NO. III. - Huey P. Long Bridge, Spanning Mississippi River approximately midway between nine & twelve mile points upstream from & west of New Orleans, Jefferson, Jefferson Parish, LA

  18. 8? x 10? black and white photographic print made from ...

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

    8? x 10? black and white photographic print made from original 1933, 8? x 10? black and white photographic negative. New 4? x 5? archival negative made from print. Original photographer unknown. Original 8? x 10? negative located in the files of the New Orleans Public Belt Railroad administrative offices at 5100 Jefferson Highway, Jefferson, LA 70123. DECEMBER 18, 1933 PHOTOGRAPH NO. 87 OF CONTRACT NO. 3 SHOWING MAIN BRIDGE SAND ISLAND FILL PIER I. - Huey P. Long Bridge, Spanning Mississippi River approximately midway between nine & twelve mile points upstream from & west of New Orleans, Jefferson, Jefferson Parish, LA

  19. NEARSHORE SAND SOURCES FOR AMERICAN SAMOA: AN ALTERNATIVE TO USING BEACH SAND.

    USGS Publications Warehouse

    Dingler, John R.; Reiss, Thomas E.

    1987-01-01

    Using a combination of geophysical techniques, in situ observations, and sampling by scuba divers, we investigated along the south shore of Tutuila Island, American Samoa, for nearshore sand deposits. To minimize the impact of future sand dredging on the island's littoral sediments, the search took place in a narrow zone between the outside of the fringing reef and the 30-m bathymetric contour. Because the sand will be used by the Samoans in a variety of ways, an area high in siliciclastic sand - Nua-Se'etaga Bay - and two areas containing only carbonate sand - Faga'itua Bay and Nafanua Bank - were inspected in detail. Results of the exploration program are discussed.

  20. UMore Park Sand and Gravel Resources Project University of Minnesota

    E-print Network

    Netoff, Theoden

    UMore Park Sand and Gravel Resources Project University of Minnesota Public Comment Forum and Open ­ Steven Lott, Co-project manager, UMore Park Sand and Gravel Resources Project 6:40 The UMore Park Sand

  1. Noise exposure and hearing loss among sand and gravel miners.

    PubMed

    Landen, Deborah; Wilkins, Steve; Stephenson, Mark; McWilliams, Linda

    2004-08-01

    The objectives of this study were to describe workplace noise exposures, risk factors for hearing loss, and hearing levels among sand and gravel miners, and to determine whether full shift noise exposures resulted in changes in hearing thresholds from baseline values. Sand and gravel miners (n = 317) were interviewed regarding medical history, leisure-time and occupational noise exposure, other occupational exposures, and use of hearing protection. Audiometric tests were performed both before the work shift (following a 12-hour noise-free interval) and immediately following the work shift. Full shift noise dosimetry was conducted. Miners' noise exposures exceeded the Recommended Exposure Limit (REL) of the National Institute for Occupational Safety and Health (NIOSH) for 69% of workers, and exceeded the Mine Safety and Health Administration's action level for enrollment in a hearing conservation program for 41% of workers. Significantly higher noise exposures occurred among employees of small companies, among workers with a job classification of truck driver, among males, and among black workers. Hearing protection usage was low, with 48% of subjects reporting that they never used hearing protection. Hearing impairment, as defined by NIOSH, was present among 37% of 275 subjects with valid audiograms. Black male workers and white male workers had higher hearing thresholds than males from a comparison North Carolina population unexposed to industrial noise. Small but statistically significant changes in hearing thresholds occurred following full shift noise exposure among subjects who had good hearing sensitivity at baseline. In a logistic regression model, age and history of a past noisy job were significant predictors of hearing impairment. Overall, sand and gravel workers have excessive noise exposures and significant hearing loss, and demonstrate inadequate use of hearing protection. Well-designed hearing conservation programs, with reduction of noise exposure, are clearly needed. PMID:15238306

  2. Elastic properties of unconsolidated porous sand reservoirs

    Microsoft Academic Search

    S. N. Domenico

    1977-01-01

    The effect of compressive stress and pore fluid properties on elastic properties of unconsolidated sand reservoirs was determined by laboratory velocity and pore volume measurements on two specimens. These consisted of a naturally occurring very fine grained sand and glass beads, each with a porosity of approximately 38 percent. Compressional- and shear-wave velocities and pore compressibility were measured in the

  3. DRINKING WATER TREATMENT USING SLOW SAND FILTRATION

    EPA Science Inventory

    Recent re-interest in slow sand filtration was brought about by the needs for small communities to install treatment technologies that are effective, less costly, and easier to operate and maintain than the more sophisticated rapid sand filters. These simpler technologies for sma...

  4. Invasive plants on disturbed Korean sand dunes

    Microsoft Academic Search

    K. D. Kim

    2005-01-01

    The sand dunes in coastal regions of South Korea are important ecosystems because of their small size, the rare species found in this habitat, and the beautiful landscapes they create. This study investigated the current vegetative status of sand dunes on three representative coasts of the Korean peninsula, and on the coasts of Cheju Island, and assessed the conditions caused

  5. Sand Tray Group Counseling with Adolescents

    ERIC Educational Resources Information Center

    Draper, Kay; Ritter, Kelli B.; Willingham, Elizabeth U.

    2003-01-01

    Sand tray group counseling with adolescents is an activity-based intervention designed to help participants address specific intrapersonal concerns, learn important skills of socialization, and develop a caring community. The main focus of the group is building small worlds with miniature figures in individual trays of sand and having an…

  6. SANDIA REPORT SAND2004-4596

    E-print Network

    Ho, Cliff

    SANDIA REPORT SAND2004-4596 Unlimited Release Printed September 2004 Sensors for Environmental@ntis.fedworld.gov Online order: http://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online 2 #12;SAND2004-4596 Unlimited

  7. SANDIA REPORT SAND2014-16800

    E-print Network

    SANDIA REPORT SAND2014-16800 Unlimited Release Printed August 2014 A Comparison of Platform Options://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;3 SAND2014-16800 Unlimited Release Printed August 2014 A Comparison of Platform

  8. SANDIA REPORT SAND2014-17460

    E-print Network

    SANDIA REPORT SAND2014-17460 Unlimited Release Printed September 2014 Wave Energy Converter Effects@ntis.fedworld.gov Online order: http://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;3 SAND2014-17460 Unlimited

  9. SANDIA REPORT SAND2007-0383P

    E-print Network

    SANDIA REPORT SAND2007-0383P Unlimited Release September 2007 Impacts of IPv6 on Infrastructure@ntis.fedworld.gov Online order: http://www.ntis.gov/help/ordermethods.asp?loc=7-4-0#online #12;SAND2007-0383P Unlimited

  10. SANDIA REPORT SAND 2012-4417

    E-print Network

    SANDIA REPORT SAND 2012-4417 Unlimited Release Printed June 2012 Site Environmental Report for 2011@ntis.fedworld.gov Online order: http://www.ntis.gov/ordering.htm #12;3 SAND 2012-4417 Unlimited Release Printed June 2012

  11. SANDIA REPORT SAND2012-0304

    E-print Network

    SANDIA REPORT SAND2012-0304 Unlimited Release Printed January 2012 A Retrospective of VAWT://www.ntis.gov/help/ordermethods.asp?loc=7-4- 0#online #12;-3- SAND2012-0304 Unlimited Release Printed January 2012 A Retrospective of VAWT

  12. RADIUM REMOVAL USING SORPTION TO FILTER SAND

    EPA Science Inventory

    The study evaluated the use of a novel sand filtration process that exploits the natural capacity of filter sand to sorb radium through the use of a periodic dilute acid rinse to maintain its sorptive capacity. Batch studies were conducted to determine distribution coefficients s...

  13. Introduction to Exploring Sand and Water

    ERIC Educational Resources Information Center

    Early Childhood Today, 2006

    2006-01-01

    What happens when children pour water through a funnel? They begin to understand science and math concepts such as flow, force, gravity, and volume. What happens when children mold sand to create a tunnel? They develop skills in areas such as problem solving and predicting. They also gain knowledge about absorption and the properties of sand and…

  14. Liquefaction in Subsurface Layer of Sand

    USGS Multimedia Gallery

    Ground shaking triggered liquefaction in a subsurface layer of sand, producing differential lateral and vertical movement in a overlying carapace of unliquified sand and silt, which moved from right to left toward the Pajaro River. This mode of ground failure, termed "lateral spreading,

  15. Curious Spherical Masses in Ashdown Sands

    Microsoft Academic Search

    Geo. Abbott

    1923-01-01

    MR. HARRY E. BURNS, of Crowborough, this spring informed me of some remarkable spherical masses of sandstone in the Ashdown Sands at High Hurst Wood Quarry, and was good enough later to supply one about 10 inches in diameter to our Museum. He suggested that they might be sand casts of reptilian eggs like that of the Iguanodon. They consist

  16. Colonization patterns in Sand Martins Riparia riparia

    Microsoft Academic Search

    Gareth Jones

    1987-01-01

    Settlement patterns of Sand Martins at a sand quarry in central Scotland are described. Older birds returned to the colony before first-year individuals, and thus had the widest choice of subcolony in which to nest. A model of subcolony settlement was developed which assumed that individuals nested in subcolonies where their reproductive success was maximized. The colonization patterns observed fitted

  17. Mutations in MITF and PAX3 Cause “Splashed White” and Other White Spotting Phenotypes in Horses

    PubMed Central

    Blatter, Marlis; Brooks, Samantha A.; Burger, Dominik; Drögemüller, Cord; Gerber, Vincent; Henke, Diana; Janda, Jozef; Jude, Rony; Magdesian, K. Gary; Matthews, Jacqueline M.; Poncet, Pierre-André; Svansson, Vilhjálmur; Tozaki, Teruaki; Wilkinson-White, Lorna; Penedo, M. Cecilia T.; Rieder, Stefan; Leeb, Tosso

    2012-01-01

    During fetal development neural-crest-derived melanoblasts migrate across the entire body surface and differentiate into melanocytes, the pigment-producing cells. Alterations in this precisely regulated process can lead to white spotting patterns. White spotting patterns in horses are a complex trait with a large phenotypic variance ranging from minimal white markings up to completely white horses. The “splashed white” pattern is primarily characterized by an extremely large blaze, often accompanied by extended white markings at the distal limbs and blue eyes. Some, but not all, splashed white horses are deaf. We analyzed a Quarter Horse family segregating for the splashed white coat color. Genome-wide linkage analysis in 31 horses gave a positive LOD score of 1.6 in a region on chromosome 6 containing the PAX3 gene. However, the linkage data were not in agreement with a monogenic inheritance of a single fully penetrant mutation. We sequenced the PAX3 gene and identified a missense mutation in some, but not all, splashed white Quarter Horses. Genome-wide association analysis indicated a potential second signal near MITF. We therefore sequenced the MITF gene and found a 10 bp insertion in the melanocyte-specific promoter. The MITF promoter variant was present in some splashed white Quarter Horses from the studied family, but also in splashed white horses from other horse breeds. Finally, we identified two additional non-synonymous mutations in the MITF gene in unrelated horses with white spotting phenotypes. Thus, several independent mutations in MITF and PAX3 together with known variants in the EDNRB and KIT genes explain a large proportion of horses with the more extreme white spotting phenotypes. PMID:22511888

  18. Pupil - white spots

    MedlinePLUS

    ... pupil may appear red. This is called the "red reflex" by health care providers and is normal. Sometimes, ... the eye may appear white, or the normal red reflex may appear to be white. This not a ...

  19. Insecticide resistance in the sand fly, Phlebotomus papatasi from Khartoum State, Sudan

    PubMed Central

    2012-01-01

    Background Phlebotomus papatasi the vector of cutaneous leishmaniasis (CL) is the most widely spread sand fly in Sudan. No data has previously been collected on insecticide susceptibility and/or resistance of this vector, and a first study to establish a baseline data is reported here. Methods Sand flies were collected from Surogia village, (Khartoum State), Rahad Game Reserve (eastern Sudan) and White Nile area (Central Sudan) using light traps. Sand flies were reared in the Tropical Medicine Research Institute laboratory. The insecticide susceptibility status of first progeny (F1) of P. papatasi of each population was tested using WHO insecticide kits. Also, P. papatasi specimens from Surogia village and Rahad Game Reserve were assayed for activities of enzyme systems involved in insecticide resistance (acetylcholinesterase (AChE), non-specific carboxylesterases (EST), glutathione-S-transferases (GSTs) and cytochrome p450 monooxygenases (Cyt p450). Results Populations of P. papatasi from White Nile and Rahad Game Reserve were sensitive to dichlorodiphenyltrichloroethane (DDT), permethrin, malathion, and propoxur. However, the P. papatasi population from Surogia village was sensitive to DDT and permethrin but highly resistant to malathion and propoxur. Furthermore, P. papatasi of Surogia village had significantly higher insecticide detoxification enzyme activity than of those of Rahad Game Reserve. The sand fly population in Surogia displayed high AChE activity and only three specimens had elevated levels for EST and GST. Conclusions The study provided evidence for malathion and propoxur resistance in the sand fly population of Surogia village, which probably resulted from anti-malarial control activities carried out in the area during the past 50 years. PMID:22397726

  20. BMM SHAKEOUT AND VIBRATING CONVEYOR TRANSPORT SAND AND CASTINGS TO ...

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

    BMM SHAKEOUT AND VIBRATING CONVEYOR TRANSPORT SAND AND CASTINGS TO SEPARATIONS SCREENS. - Southern Ductile Casting Company, Shaking, Degating & Sand Systems, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  1. Acoustic detection of Immiscible Liquids in Sand

    SciTech Connect

    Geller, Jil T.; Kowalsky, Michael B.; Seifert, Patricia K.; Nihei, Kurt T.

    1999-03-01

    Laboratory cross-well P-wave transmission at 90 kHz was measured in a 61 cm diameter by 76 cm tall water-saturated sand pack, before and after introducing a non-aqueous phase organic liquid (NAPL) (n-dodecane). In one experiment NAPL was introduced to form a lens trapped by a low permeability layer; a second experiment considered NAPL residual trapped behind the front of flowing NAPL. The NAPL caused significant changes in the travel time and amplitude of first arrivals, as well as the generation of diffracted waves arriving after the direct wave. The spatial variations in NAPL saturation obtained from excavation at the end of the experiment correlated well with the observed variations in the P-wave amplitudes and travel times. NAPL residual saturation changes from NAPL flow channels of 3 to 4% were detectable and the 40 to 80% NAPL saturation in the NAPL lens was clearly visible at acoustic frequencies. The results of these experiments demonstrate that small NAPL saturations may be more easily detected with amplitude rather than travel time data, but that the relationships between the amplitude changes and NAPL saturation maybe more complex than those for velocity.

  2. Holocene stratigraphy of the Alabama inner continental shelf: Influence of shelf sand ridges on determining lithofacies architecture

    SciTech Connect

    Davies, D.J.; Parker, S.J. (Geological Survey of Alabama, Tuscaloosa, AL (United States). Energy and Coastal Geology Div.)

    1993-03-01

    Surface and subsurface distribution of lithofacies from Holocene sediments of the AL inner continental shelf was determined from a series of 59 vibracores and associated surface sediment grab sediments. Five Holocene lithofacies composed of 12 discrete microfacies were delineated based on grain size, color, sedimentary structures, shell content, and fabric of samples. These lithofacies include: (1) Graded Shelly Sand Lithofacies; (2) Clean Sand Lithofacies; (3) Dirty Sand Lithofacies; (4) Biogenic Sediment Lithofacies; and (5) Muddy Sediment Lithofacies. These represent four major depositional environments: The Shelf Sand Sheet Environment (lithofacies 1 and 2); the Sand Ridge Environment (lithofacies 1, 2, and 3); the Bay/Lagoon Environment (lithofacies 3, 4 and 5); and the Muddy Shelf Environment (lithofacies 5). East of the Main Pass of Mobile Bay, the seafloor is composed of a clean Shelf Sand Sheet with oblique shelf sand ridges; Clean Sand and Graded Shelly Sand are the dominant surface sediment types. Coarse shell beds that grade up to quartz sand units (total thickness 0.1 to 3+m) interpreted as tempestites comprise most of the upper portion of the ridges. West of the Pass, the muddier lithofacies (3 and 5) dominate surface samples. Microfacies at depth represent the early Holocene transgressive systems tract; these include the Muddy Shelf Depositional Environment and the filled estuaries and bays of the flooded Pleistocene fluvial valleys represented by the Bay/Lagoon Depositional Environment. The AL inner shelf provides an excellent model of the variability of sedimentation mode in time and space during deposition of a transgressive systems tract. Development of the palimpsest sand sheet/ridge complex progressed on the eastern shelf due to shut off of sediment influx, westward longshore currents, and episodic incidence of major hurricanes. On the western shelf a patchy distribution of muddier sediments developed from input of floodwaters from Mobile Bay.

  3. Batch and column studies of adsorption of Li, Ni and Br by a reference sand for contaminant transport experiments

    SciTech Connect

    Seigel, M.D. [Sandia National Labs., Albuquerque, NM (United States)] [Sandia National Labs., Albuquerque, NM (United States); Ward, D.B.; Bryan, C.R. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others] [Univ. of New Mexico, Albuquerque, NM (United States); and others

    1995-09-01

    A processed quartz sand (Wedron 510), mined from the St. Peter sandstone, has been characterized by a variety of chemical and physical methods for use as a reference porous media in transport model validation experiments. Wedron 510 sand was used in an intermediate-scale experiment involving migration of Ni, Li and Br through a 6-m high x 3-m diameter caisson. Ni and Li adsorption/desorption, and Li/Ni site-competition experiments yielded information on the importance of the trace mineral phases to adsorption of Li and Ni by the sand. The presence of an iron hydroxide coating similar to goethite on the sand grains is suggested by visual observation and leaching experiments. Kaolinite was identified by SEM and XRD as a significant trace mineral phase in the sand and occurs as small particles coating the sand grains. Quartz, the predominant constituent of the sand by weight, does not appear to contribute significantly to the adsorption properties of the sand. Qualitatively, the adsorption properties of the sand can be adequately modeled as a two-mineral system (goethite and kaolinite). The studies described in this report should provide a basis for understanding transport of Ni, Li and Br through porous media similar to the reference sand. Techniques were developed for obtaining parameter values for surface complexation and kinetic adsorption models for the sand and its mineral components. These constants can be used directly in coupled hydrogeochemical transport codes. The techniques should be useful for characterization of other natural materials and elements in high-level nuclear waste in support of coupled hydrogeochemical transport calculations for Yucca Mountain.

  4. Hematite Outlier and Sand Dunes

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 4 December 2003

    This image shows a crater just south of the edge of the famous hematite-bearing surface, which is visible in the context image as a smooth area to the north. The crater has two features of immediate note. The first is a layered mound in the north part of the crater floor. This mound contains hematite, and it is an outlying remnant of the greater deposits to the north that have otherwise completely disappeared in this crater. The second feature is a dune field in the center of the crater floor, with dark dunes indicating winds from the northwest. The dunes grade into a dark sand sheet with no coherent structure, indicating that the sand layer thins out to the south and east.

    Image information: VIS instrument. Latitude -4.4, Longitude 357.3 East (2.7 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  5. Geochemistry of beach sands from Sithonia Peninsula (Chalkidiki, Northern Greece)

    NASA Astrophysics Data System (ADS)

    Papadopoulos, A.; Christofides, G.; Pe-Piper, G.; Koroneos, A.; Papadopoulou, L.

    2015-02-01

    Thirty beach sand samples from the granitic shoreline of the Sithonia Plutonic Complex (SPC) were analyzed for their REE and major element contents. The obtained results are compared with the adjacent SPC rock-types, in order to determine any enrichments or depletions. Among the samples enriched in REE, three are seasonal deposits of heavy minerals and their concentrations are controlled by the action of sea-waves. The available geochemical characteristics were also used to confirm the parental rocks of the beach sands, which are the SPC rock-types. The heavy fractions (total, total magnetic and total non-magnetic) of the beach sands were correlated with the REE concentrations, revealing a strong correlation between the heavy non-magnetic fraction and REE content. Among the minerals of the heavy non-magnetic fraction, monazite seems to control the REE content in the heavy mineral-enriched samples, whereas in the rest of the samples allanite, belonging to the heavy magnetic fraction may be the most important REE mineral.

  6. White Dwarf Stars

    Microsoft Academic Search

    Steven Kawaler; Michael Dahlstrom

    2000-01-01

    A white dwarf is a very dense star: The earth-sized remains of a Sun-like star that has burned all of its nuclear fuel. Although it's unable to carry out the workaday activities of a living star, a white dwarf is still an interesting object to astronomers. For one thing, white dwarfs experience \\

  7. White dwarf stars

    Microsoft Academic Search

    J. Liebert

    1980-01-01

    Observations and properties of white-dwarf stars are reviewed. Observational constraints are discussed in terms of methods of discovery, selection effects, white dwarfs in binaries and clusters, stellar colors, spectral types, and kinematic properties. The following stellar and atmospheric parameters are examined: astrometric masses and radii; temperatures, radii, and gravities of DA stars; abundances in white dwarfs with helium atmospheres; and

  8. Confronting White Privilege

    ERIC Educational Resources Information Center

    Swalwell, Katy

    2012-01-01

    Even as the United States becomes more diverse, a new era of "white flight" is unfolding. Whether they live in urban, suburban or rural communities, white students are likely to attend schools that reinforce their perceptions of cultural dominance. The average white student attends a school where 77 percent of the student body is of their race.…

  9. Influence of sand grain diameter and wind velocity on lift-off velocities of sand particles.

    PubMed

    Bo, Tian-Li; Zheng, Xiao-Jing; Duan, Shao-Zhen; Liang, Yi-Rui

    2013-05-01

    In this paper, the velocities of sand particles near the sand bed in the saltation cloud were measured in a wind tunnel through an improved experimental scheme of the Particle Image Velocimetry (PIV) system. The influences of the diameter of sand particles in the saltation cloud and wind velocity on the probability distribution function (PDF) of lift-off velocities of sand particles were investigated. Results demonstrate that for the sand particles saltating above the sand bed with the mean grain diameter (d m = 0.3 mm), smaller and larger ones have the same velocity distribution, and wind velocity has no obvious influence on the distribution shape of the lift-off velocities, i.e., the PDFs of the horizontal and vertical lift-off velocities both follow a lognormal distribution, but the diameter of sand particles in the saltation cloud and wind velocity have an influence on the parameters of the PDF of horizontal and vertical lift-off velocities. Eventually, we present formulas to describe the PDF of lift-off velocities of sand particles with regard to the influence of wind velocity and the diameter of sand particles in the saltation cloud above the sand bed with d m = 0.3 mm. PMID:23695368

  10. Critical state of sand matrix soils.

    PubMed

    Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong

    2014-01-01

    The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, ?, and ?. The range of the value of M, ?, and ? is 0.803-0.998, 0.144-0.248, and 1.727-2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated. PMID:24757417

  11. Critical State of Sand Matrix Soils

    PubMed Central

    Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong

    2014-01-01

    The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, ?, and ?. The range of the value of M, ?, and ? is 0.803–0.998, 0.144–0.248, and 1.727–2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated. PMID:24757417

  12. Fecal indicators in sand, sand contact, and risk of enteric illness among beachgoers

    PubMed Central

    Heaney, Christopher D.; Sams, Elizabeth; Dufour, Alfred P.; Brenner, Kristen P.; Haugland, Richard A.; Chern, Eunice; Wing, Steve; Marshall, Stephen; Love, David C.; Serre, Marc; Noble, Rachel; Wade, Timothy J.

    2011-01-01

    Background Beach sand can harbor fecal indicator organisms and pathogens, but enteric illness risk associated with sand contact remains unclear. Methods In 2007, visitors at two recreational marine beaches were asked on the day of their visit about sand contact. Ten to 12 days later, participants answered questions about health symptoms since the visit. F+ coliphage, Enterococcus, Bacteroidales, fecal Bacteroides, and Clostridium spp. in wet sand were measured using culture and molecular methods. Results We analyzed 144 wet sand samples and completed 4,999 interviews. Adjusted odds ratios (aORs) were computed, comparing those in the highest tertile of fecal indicator exposure with those who reported no sand contact. Among those digging in sand compared with those not digging in sand, a molecular measure of Enterococcus spp. (calibrator cell equivalents/g) in sand was positively associated with gastrointestinal (GI) illness (aOR = 2.0 [95% confidence interval (CI) = 1.2–3.2]) and diarrhea (2.4 [1.4–4.2]). Among those buried in sand, point estimates were greater for GI illness (3.3 [1.3–7.9]) and diarrhea (4.9 [1.8–13]). Positive associations were also observed for culture-based Enterococcus (colony-forming units/g) with GI illness (aOR digging = 1.7 [1.1–2.7]) and diarrhea (2.1 [1.3–3.4]). Associations were not found among non-swimmers with sand exposure. Conclusions We observed a positive relationship between sand contact activities and enteric illness as a function of concentrations of fecal microbial pollution in beach sand. PMID:22157306

  13. Invasive plants on disturbed Korean sand dunes

    NASA Astrophysics Data System (ADS)

    Kim, Kee Dae

    2005-01-01

    The sand dunes in coastal regions of South Korea are important ecosystems because of their small size, the rare species found in this habitat, and the beautiful landscapes they create. This study investigated the current vegetative status of sand dunes on three representative coasts of the Korean peninsula, and on the coasts of Cheju Island, and assessed the conditions caused by invasive plants. The relationships between the degree of invasion and 14 environmental variables were studied. Plots of sand dunes along line transects perpendicular to the coastal lines were established to estimate vegetative species coverage. TWINSPAN (Two-Way Indicator Species Analysis), CCA (Canonical Correspondence Analysis), and DCCA (Detrended Canonical Correspondence Analysis) were performed to classify communities on sand dunes and assess species composition variation. Carex kobomugi, Elymus mollis, and Vitex rotundifolia were found to be the dominant species plotted on the east, the west, and the peripheral coasts of Cheju Island, respectively. Vegetation on the south coast was totally extinct. The 19 communities, including representative C. kobomugi, C. kobomugi- Ixeris repens, C. kobomugi- Oenothera biennis, E. mollis, Lolium multiflorum- Calystegia soldanella, and V. rotundifolia- C. kobomugi, were all classified according to TWINSPAN. Oenothera biennis and L. multiflorum were exotics observed within these native communities. CCA showed that invasive native and exotic species distribution was segregated significantly, according to disturbance level, exotic species number, gravel, sand and silt contents, as well as vegetation size. It further revealed that human disturbance can strongly favor the settlement of invasive and exotic species. Restoration options to reduce exotic plants in the South Korean sand dune areas were found to be the introduction of native plant species from one sand dune into other sand dune areas, prohibition of building and the introduction of exotic soils, and conservation of surrounding sand dune areas.

  14. Skin friction for steel piles in sand 

    E-print Network

    Sulaiman, Ibrahim Hikmat

    1967-01-01

    - The Arkansas Pile Test iv vii 12 Art. 2. 5 - Skin Friction, Soil Shear Strength, snd Pile Movement Chapter III, Laboratory Tests on Small Piles in Sand Az't. 3. 1 ? Soil Classification Art. 3. 2 - Testing Apparatus 23 25 Art. 3. 3 ? Preparation... 12. 13. Grain Size Distribution by Sieve Analysis Triaxial Cell Arranged for Loading 24 26 14. Skin Friction Versus Pile Movement for Firm Sand. Iaboratory Test, Data 33 15. Skin Friction Versus Pile Movement for Dense Sand. Laboratory Test...

  15. Skin friction for steel piles in sand

    E-print Network

    Sulaiman, Ibrahim Hikmat

    1967-01-01

    SkiN FRICTION FOR STEZL PIIZS IN SAND A Theeia by I. H. Sulaiman Submittei io the graduate College of t, he Texan AAB Univen-ity in Ixantial fulfil. ment of bhe zequiremenbu for the degree of NASTZR 0F SCISNCZ May 196'7 bsrjor Subject...: Civil Engineering SKIN FRICTION FOR STEEL PILES IN SAND A Thesis by I. H. Sulaiman Approved as to style and content by: Chairman of C mmittee Head of Department Memb Member 111 Skin Friction For Steel Piles in Sand (May 1967) Ibr shim Hikmat...

  16. A Physical Taxonomy of Martian Sand and Dust Grainsat the Phoenix Landing Site

    NASA Astrophysics Data System (ADS)

    Marshall, John; Stoker, Carol

    2014-11-01

    A quantitative taxonomy of martian sand and dust grains for soil samples at the Phoenix lander site has been developed from the mission’s optical microscope data with a resolution of 4 ?m per pixel. Approx. 3-4000 grains were analyzed for color, hue, size, shape, surface texture, aspect ratio, and optical properties. At least 26 types of sand and dust grains have been identified. Grain colors include black, brown, orange, red, white, and clear. Most grains are opaque, but many are translucent or transparent. Grain shapes range from botryoidal, blackberry-like, bead-like and rounded, to subrounded, elongate, angular, and highly irregular forms. Surface textures range from knobbly, rough, and multifaceted to smooth and polished. Surface reflectivity varied from dull to shiny to specularly reflective. Materials may include augite, pyroxenes, olivine, volcanic glass, hematite, other iron oxides, and salts. Grain size of the sand has a modal value of ~90 ?m, but there is no gradation into dust sizes, indicating a bimodal distribution of the samples. The dust was probably imported into the region from aeolian dust storms. This accords with a mineralogical dissimilarity between the sand and dust grain populations. The sand is dominated by black and brown grains; the dust is dominated by orange grains. The Phoenix site also has centimeter and larger stones in abundance that again have no apparent gradation into the sand size material. Thus, the Phoenix landing site soil appears multimodal. The soil appears to be magnetically susceptible, but it is unclear what the source of magnetism might be. Specific magnetic minerals were not identified in the samples with the possible exception of paramagnetic microbotryoidal hematite. The soil was nevertheless adhesive to the substrates and internally cohesive (forming spherical aggregates) owing to van der Waals forces and possibly salt/moisture bonding.

  17. Laser Sintering of Silica Sand – Mechanism and Application to Sand Casting Mould

    Microsoft Academic Search

    X. H. Wang; J. Y. H. Fuh; Y. S. Wong; Y. X. Tang

    2003-01-01

    Silica sand is commonly used in the foundry industry. With a high melting point of 160° C, the silica sand is normally sintered in a high-temperature furnace. However, silica with contents of calcium, aluminium, magnesium, and chlorine, etc. can form low-melting point eutectics. Therefore, a relatively low-power laser can be used to sinter the silica sand directly. The investigation of

  18. Modeling the response of shoreface-connected sand ridges to sand extraction on an inner shelf

    NASA Astrophysics Data System (ADS)

    Nnafie, A.; de Swart, H. E.; Calvete, D.; Garnier, R.

    2014-05-01

    Shoreface-connected sand ridges are rhythmic bedforms that occur on many storm-dominated inner shelves. The ridges span several kilometers, are a few meters high, and they evolve on a timescale of centuries. A process-based model is used to gain a fundamental insight into the response of these ridges to extraction of sand. Different scenarios of sand extraction (depth, location, and geometry of the extraction area; multiple sand extractions) are imposed. For each scenario, the response timescale as well as the characteristics of the new equilibrium state are determined. Results show that ridges partially restore after extraction, i.e., the disturbed bathymetry recovers on decadal timescales. However, in the end, the ridge original sand volume is not recovered. Initially, most sand that accomplishes the infill of the pit originates from the area upstream of the extraction, as well as from the areas surrounding the pit. The contribution of the latter strongly decreases in the subsequent time period. Depending on the location of the pit, additional sand sources contribute: First, if the pit is located close to the downstream trough, the pit gains sand by reduction of sand transport from the ridge to this trough. Second, if the pit is located close to the adjacent outer shelf, the ridge recovery is stronger due to an import of sand from that area. Furthermore, pits that are located close to the nearshore zone have a weak recovery, deeper pits have longer recovery timescales, wide and shallow pits recover most sand, while multiple sand pits slow down the recovery process.

  19. Depositional environments of Schuler Formation (Cotton Valley Sands), Upshur County, Texas

    Microsoft Academic Search

    Joe A. Kast

    1983-01-01

    Exploration for tight gas (FERC Section 107) production from the Schuler Formation (Cotton Valley sands) has provided recent data for the recognition of the lower Schuler (Shongaloo member) shoreface facies and delineation of the upper Schuler (Dorcheat member) delta plain complex in Upshur County. Shoreface facies within the lower Schuler have a typical funnel-shaped log pattern (coarsening-upward clastic). In core,

  20. Sorption and filtration of metals using iron-oxide-coated sand

    Microsoft Academic Search

    Mark M. Benjamin; Ronald S. Sletten; Robert P. Bailey; Thomas Bennett

    1996-01-01

    Iron oxides are good adsorbents for uncomplexed metals, some metal-ligand complexes, and many metal oxyanions. However, the adsorbent properties of these oxides are not fully exploited in wastewater treatment operations because of difficulties associated with their separation from the aqueous phase. This paper describes experiments in which iron oxides were coated onto the surface of ordinary filter sand, and this

  1. Microwave and Millimeter-Wave Attenuation in Sand and Dust Storms

    Microsoft Academic Search

    Xiao-Ying Dong; Hsing-Yi Chen; Dong-Hui Guo

    2011-01-01

    The attenuation and phase delay due to sand and dust storms are obtained by using the effective material property tech- nique and general formulation of the complex propagation factor. The validity of attenuation is verified by Ghobrial et al.'s formula. Attenuations obtained for various frequencies are shown in this letter. It is found that the attenuation decreases sharply as the

  2. Numerical modeling of stress–strain behavior of sand under cyclic loading

    Microsoft Academic Search

    Habib Shahnazari; Yasser Dehnavi; Amir Hossein Alavi

    2010-01-01

    Analysis of soil response to cyclic loading is a complex problem due to the participation of a large number of loading conditions and physical properties. In this study, a promising variant of genetic programming (GP), namely multi expression programming (MEP) is utilized to model stress–strain behavior of sands subjected to large amplitude regular cyclic loading. Generalized MEP-based formulations are derived

  3. Dynamical evolution of sand ripples under water Alexandre Stegner1

    E-print Network

    Wesfreid, José Eduardo

    Dynamical evolution of sand ripples under water Alexandre Stegner1 and Jose´ Eduardo Wesfreid2 1 an experimental study on the evolution of sand ripples formed under the action of an oscillatory flow. An annular sand-water cell was used in order to investigate a wide range of parameters. The sand ripples follow

  4. 1 INTRODUCTION Oil sand has unique properties exhibits performance

    E-print Network

    Joseph, Tim Grain

    1 INTRODUCTION Oil sand has unique properties exhibits performance akin to sandstone in winter seated on oil sand can sink after a number of cycles with ground softening oc- curring rapidly due true for unconsolidated sands such as oil sand. 2 ASSUMPTIONS Following the work of Sharif-Abadi (2006

  5. Sand dynamics at the mouth of a rock-bound, tide-dominated estuary

    NASA Astrophysics Data System (ADS)

    FitzGerald, D. M.; Buynevich, I. V.; Fenster, M. S.; McKinlay, P. A.

    2000-03-01

    The lowermost Kennebec River is a relatively narrow, deep, bedrock-cut estuary situated along the highly indented, central coast of Maine. A large tidal prism and strong tidal currents control bedload sediment transport at the estuary mouth. Riverine sediment is introduced to the estuary during spring freshets when freshwater discharge may increase by an order of magnitude. During the same time, some of the existing estuarine sediment is exported to the nearshore. A barrier adjacent to the estuary is the product of an abundant riverine sand supply and numerous bedrock ridges, which anchor this sand deposit. A variety of sedimentologic, geomorphic, and hydraulic data collected over a 14-year period document a clockwise, sand-circulation cell that involves the exchange of bedload among the entrance channel to the estuary, adjacent beaches, nearshore, and offshore region. Tidal currents transport sand from the estuary through a subsidiary channel, bordered on both sides by bedrock islands, to an offshore subtidal bar. Northeast storm waves breaking along this outer bar move sand westward and landward toward the beach, leading to the development of large bar complexes. The welding of a bar complex to the western end of Hunnewell Beach occurs every 6-9 years and adds 2-300,000 m 3 of sand to the shoreline. Sediment transport calculations along the outer bar are consistent with this volume of sand. The sediment gyre is completed as beach sands are moved eastward along the beach and dumped into the estuarine channel. This movement of sand is produced by wave action and tidal currents that enter the estuary peripherally during the flooding tide. During the ebb cycle, strong tidal currents flowing seaward through the subsidiary channel advect water from along the beach, which enhances sand transport into the estuary. Thirteen years of beach profile surveys demonstrate a good correspondence between bar welding events and short-term (1-4 years) accretionary shoreline changes. However, the volumetric changes of Hunnewell Beach cannot be accounted for by bar welding alone. The apparent movement of sand between Hunnewell Beach and other sand is further evidenced by the 135 year record of historical shoreline changes that reveal up to 200 m of shoreline excursions over a 26 year period. These data suggest that erosional-depositional trends along Hunnewell Beach are complex and the result of the exchange of sand among the adjacent beaches, nearshore zone, Fox and Wood Island tombolos, Kennebec River channel, and offshore region. The effects of major spring floods and strong bedrock influences produce patterns of sedimentation and a distribution of sand bodies at the mouth of Kennebec River that differ markedly from accepted estuarine models that are based on the relative importance of wave and tidal energy. This study demonstrates the need to consider structural controls when using these models.

  6. On the nature of Athabasca Oil Sands.

    PubMed

    Czarnecki, Jan; Radoev, Boryan; Schramm, Laurier L; Slavchev, Radomir

    2005-06-30

    The existence of a thin aqueous film, separating bitumen (a form of heavy oil) from inorganic solids in Athabasca Oil Sands, is analysed based on "first principles". There is a general consensus in the literature on the hydrophilic character of the solids in oil sands. However, a review of the references cited in support of the solids being encapsulated in thin water envelopes produced a surprising lack of evidence. A theoretical analysis indicates that a water film separating clean, hydrophilic quartz and bitumen is stable under most conditions, and unstable for acidic oil sand ores. The existence of water-wet solids in the Athabasca Oil Sands remains a reasonable yet unproven postulate. It could therefore be dangerous to accept the water-wet solids postulate and then use it to interpret other phenomena. PMID:15936283

  7. Humate in coastal sands of northwest Florida

    Microsoft Academic Search

    V. E. Swanson; J. G. Palacas

    1965-01-01

    Layers of dune and beach sand along the north coast of the Gulf of Mexico are cemented or impregnated with a conspicuous dark-brown to black water-solute organic substance herein called humate. The humate-cemented sand, generally 6 inches to 3 feet thick but as much as 15 feet thick in some places, forms one or several irregular layers in the subsurfaces

  8. Tar sands leachate study. Final report

    Microsoft Academic Search

    D. W. Grosse; L. McGowan

    1984-01-01

    An inhouse research project was conducted by the EPA's Industrial Environmental Research Laboratory (IERL) at the TandE Facility in Cincinnati, Ohio, to provide information concerning the potential for release of contaminants to groundwater from in-situ and above-ground processed tar sands. This study examined the composition of the leachate that may be generated from raw tar sand cores and spent tar

  9. Source provenance of carbonate grains in the Wahiba Sand Sea, Oman, using a new LIBS method

    NASA Astrophysics Data System (ADS)

    Pease, Patrick; Tchakerian, Vatche

    2014-12-01

    The Wahiba Sand Sea is a large dune system composed of northern and southern zones. The dunes receive sand from multiple sources including two fluvial systems draining mountain basins, older underlying dunes, and a large coastline. Although the sand sea is distinctly divided into geomorphic regions with different dunes types, ages, and bulk mineral compositions, the ubiquitous presence of carbonate grains throughout the dune field has led to models that suggest the coast and shallow shelf is the direct and primary source of sediment for the entire sand sea. This study uses a novel method which couples selective, grain-by-grain analysis using laser-induced breakdown spectroscopy (LIBS) of a single mineral species with the classification method of Soft Independent Modeling of Class Analogy (SIMCA). The analysis of carbonate grains using the LIBS method reveals that the carbonates are comprised of several sub-populations that are well mixed throughout the dune field. Individual sources of carbonate grains are also composed of multiple sub-populations creating further complexity. Sand in the Northern Wahiba is predominantly, and directly, derived from wadi systems that lie on the west and northeast sides of the dunes and once bordered the southern end of the dunes. The Southern Wahiba is composed of a more complex mixture of sand derived from the coast; however, the coastal sediments themselves were dominantly derived from the fluvial systems in the region, along with sediment of unknown original source. The new LIBS/SIMCA method of grain-by-grain analysis shows promise for unraveling complex mixing patterns in sedimentary deposits.

  10. Thermally Induced Wettability Change During SAGD for Oil Sand Extraction

    E-print Network

    Unal, Yasin

    2014-08-20

    appreciated. vi NOMENCLATURE 2D two-dimensional AOSTRA Alberta Oil Sands Technology and Research Authority BDNS barium dinonyl naphthalene sulfonate BIC Brookhaven Instruments Corporation CMG Computer Modelling Group Ltd. CSS cyclic steam....) is from oil sands. Most of these oil sands are located in Alberta. A typical oil sand is composed of approximately 83% sand, 14% bitumen, and 3% water by weight, and almost 90% of the solid matrix is quartz, with the rest being silt and clay (Nasr...

  11. Effects of advanced oxidation on green sand properties via iron casting into green sand molds.

    PubMed

    Wang, Yujue; Cannon, Fred S; Voigt, Robert C; Komarneni, Sridhar; Furness, J C

    2006-05-01

    The effects of advanced oxidation (AO) processing on the properties of green sand were studied via pouring cast iron into green sand molds. Upon cooling, the green sand molds were autopsied at various distances from the metal-sand interface. Autopsy green sand samples collected from a mold that incorporated AO water were characterized and compared to controlled samples collected from a similar autopsied mold made with conventional tap water (TAP). It was found that the AO processing removed a coating of coal pyrolysis products from the clay surface that typically accumulated on the clay surface. As a result, the AO-conditioned green sand retained 10-15% more active clay as measured bythe standard ultrasonic methylene blue titration than did the TAP-conditioned green sand. The AO processing also nearly doubled the generation of activated carbon from the normalized amount of coal composition of the green sand during the casting process. The AO-enhanced activated carbon generation and the AO-incurred clay surface cleaning provided the AO-conditioned green sand with higher normalized pore volume, and thus higher normalized m-xylene adsorption capacity, i.e., relative to before-metal-pouring conditions. Furthermore, mathematical analysis indicated that the AO-conditioned green sand better retained its important properties after pouring than did the TAP-conditioned green sand. Effectively, this meant after metal pouring, the AO-conditioned sample offered about the same net properties as the TAP-conditioned sample, even though the AO-conditioned sample contained less clay and coal before metal pouring. These results conformed to the full-scale foundry empirical finding that when AO is used, foundries need less makeup clay and coal addition through each casting cycle, and they release less air emissions. PMID:16719117

  12. Magnetic White Dwarfs

    E-print Network

    Ferrario, Lilia; Gaensicke, Boris

    2015-01-01

    In this paper we review the current status of research on the observational and theoretical characteristics of isolated and binary magnetic white dwarfs (MWDs). Magnetic fields of isolated MWDs are observed to lie in the range 10^3-10^9G. While the upper limit cutoff appears to be real, the lower limit is more difficult to investigate. The incidence of magnetism below a few 10^3G still needs to be established by sensitive spectropolarimetric surveys conducted on 8m class telescopes. Highly magnetic WDs tend to exhibit a complex and non-dipolar field structure with some objects showing the presence of higher order multipoles. There is no evidence that fields of highly magnetic WDs decay over time, which is consistent with the estimated Ohmic decay times scales of ~10^11 yrs. MWDs, as a class, also appear to be more massive than their weakly or non-magnetic counterparts. MWDs are also found in binary systems where they accrete matter from a low-mass donor star. These binaries, called magnetic Cataclysmic Variab...

  13. Variation in sand body types on the eastern Bering Sea epicontinental shelf.

    USGS Publications Warehouse

    Nelson, C.H.; Dupre, W.R.; Field, M.E.; Howard, J.D.

    1982-01-01

    The eastern epicontinental shelf of the Bering Sea is characterized by variations in river and glacial sediment supply, wave energy, tidal range (microtidal to mesotidal), and tidal, geostrophic, and storm-induced currents. These factors, combined with the effect of the Holocene rise in sea level, have resulted in the formation of a complex assemblage of generally linear sand bodies of similar morphology anad lithology, but different origins. The sand bodies are large features found from the present shoreline to tens of kilometers offshore, in water depths up to 50m. -from Authors

  14. Standardization and Whiteness: One and the Same?

    ERIC Educational Resources Information Center

    Weilbacher, Gary

    2012-01-01

    The article "There Is No Culturally Responsive Teaching Spoken Here: A Critical Race Perspective" by Cleveland Hayes and Brenda C. Juarez suggests that the current focus on meeting standards incorporates limited thoughtful discussions related to complex notions of diversity. Our response suggests a strong link between standardization and White

  15. Changes in induced polarization associated with the sorption of sodium, lead, and zinc on silica sands.

    PubMed

    Vaudelet, P; Revil, A; Schmutz, M; Franceschi, M; Bégassat, P

    2011-08-15

    Low-frequency dielectric spectroscopy can be measured in terms of a conductance and a phase lag between the electrical current and the electrical field. This conductance and phase lag can be written as into a complex conductivity with both an in-phase and quadrature components that are frequency dependent. In sands, the low-frequency (10 mHz-40 kHz) spectra of the complex conductivity are dominated by the polarization of the electrical double layer (especially the internal part of the electrical double layer called the Stern layer) and the Maxwell-Wagner polarization (typically above 100 Hz). We present a polarization that is able to explain the complex conductivity spectra including the grain size distribution, the porosity, and the complexation of the mineral surface with the ions of the pore water. To test this model, we investigate the sorption of various cations (Na, Pb, Zn) characterized by different affinities with the surface of silica. Sand column experiments were carried out to see the change in the complex conductivity during the advective/dispersive transport of a lead nitrate solution and a zinc sulfate solution, replacing a sodium chloride solution in the pore space of the sand. The complex conductivity model is able to explain the change of the phase over time. PMID:21570082

  16. South America and a Few Grains of Sand. Part 1: Beach Sands.

    ERIC Educational Resources Information Center

    Potter, Paul Edwin

    1986-01-01

    Continental geology and tectonics are explored through this study of modern beach sands of South America. This report assesses how well petrographic studies of sandstones can recreate continental geography. Data on the petrography of 218 modern South American beach sands are presented and analyzed. The five major mineral associations of light…

  17. Recovery of Ilmenite and Other Heavy Minerals from Teri Sands (Red Sands) of Tamil Nadu, India

    Microsoft Academic Search

    N. Babu; N. Vasumathi; R. Bhima Rao

    The red sand which is known as Teri sand in Tamil Nadu consists of 5.5% Total Heavy Minerals (THM) out of which 3.7% is ilmenite. The other minerals, zircon, sillimanite and garnet are in the order of abundance identified. On processing this feed to recover ilmenite by using spirals followed by dry high intensity magnetic separator and high tension separator,

  18. Sand fly fauna (Diptera, pcychodidae, phlebotominae) in different leishmaniasis-endemic areas of ecuador, surveyed using a newly named mini-shannon trap.

    PubMed

    Hashiguchi, Kazue; Velez N, Lenin; Kato, Hirotomo; Criollo F, Hipatia; Romero A, Daniel; Gomez L, Eduardo; Martini R, Luiggi; Zambrano C, Flavio; Calvopina H, Manuel; Caceres G, Abraham; Hashiguchi, Yoshihisa

    2014-12-01

    To study the sand fly fauna, surveys were performed at four different leishmaniasis-endemic sites in Ecuador from February 2013 to April 2014. A modified and simplified version of the conventional Shannon trap was named "mini-Shannon trap" and put to multiple uses at the different study sites in limited, forested and narrow spaces. The mini-Shannon, CDC light trap and protected human landing method were employed for sand fly collection. The species identification of sand flies was performed mainly based on the morphology of spermathecae and cibarium, after dissection of fresh samples. In this study, therefore, only female samples were used for analysis. A total of 1,480 female sand flies belonging to 25 Lutzomyia species were collected. The number of female sand flies collected was 417 (28.2%) using the mini-Shannon trap, 259 (17.5%) using the CDC light trap and 804 (54.3%) by human landing. The total number of sand flies per trap collected by the different methods was markedly affected by the study site, probably because of the various composition of species at each locality. Furthermore, as an additional study, the attraction of sand flies to mini-Shannon traps powered with LED white-light and LED black-light was investigated preliminarily, together with the CDC light trap and human landing. As a result, a total of 426 sand flies of nine Lutzomyia species, including seven man-biting and two non-biting species, were collected during three capture trials in May and June 2014 in an area endemic for leishmaniasis (La Ventura). The black-light proved relatively superior to the white-light with regard to capture numbers, but no significant statistical difference was observed between the two traps. PMID:25589880

  19. 1. Elevation from E. White Holly in foreground, with White ...

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

    1. Elevation from E. White Holly in foreground, with White Sage behind. - U.S. Coast Guard Cutter WHITE HOLLY, U.S. Coast Guard 8th District Base, 4640 Urquhart Street, New Orleans, Orleans Parish, LA

  20. Facies and paleoenvironments of Campanian Basal Belly River sands, southern Alberta, Canada: a case study based on multidisciplined approach using both conventional sedimentology and palynofacies synthesis

    SciTech Connect

    Sabry, H.

    1987-05-01

    Basal Belly River sands are not a single, continuous body but are composed of many separate bodies of sand occupying slightly different stratigraphic positions. The shape of the Belly River Formation, its internal geometry, and its lithology fit well with the clastic wedge association of deltaic sediments. The textural and mineralogical immaturity of most of the Belly River sediments indicates rapid deposition, also characteristic of deltaic deposits. A detailed sedimentologic and palynofacies investigation of over 2930 ft of core from several wells in southern Alberta has led to the recognition of several distinct lithofacies. The lithofacies of the subaqueous part of the delta are (1) nearshore marine bar and interbar marine facies, (2) prodelta marine shales and siltstones, and (3) distal and proximal delta front sand facies. The subaerial part of the delta and interdeltaic shoreline sediments consists of 15 lithofacies that can be grouped as follows: estuarine distributary channel; barrier bar; barrier face and back barrier tidal channel; subtidal sand and shale-sand channels and flats; peat swamp; transgressive tidal sand ridges; and upper delta plain/alluvial meandering rivers and overbank complexes. Best reservoir developments are found in barrier bar, transgressive tidal sand ridges, subtidal channels, and point bar facies. The Basal Belly River sands of prograding deltaic origin experienced episodes of modification from an early river-dominated delta to a tidally dominated one later. This is evident from the paleogeography, geometry, continuity, and internal characteristics of the Basal Belly River sand bodies.

  1. Complex Conductivity Response to Nanomaterials in a Sand Matrix

    Microsoft Academic Search

    R. Joyce; D. Werkema; E. Atekwana

    2008-01-01

    Nano-scale metallic particles are being used with increasing frequency in a variety of industrial, medical, and environmental remediation applications. The fate and transport of such materials in the subsurface is not fully understood, neither is the impact of these materials on human health. Materials at this small nano-scale sometimes have unusual physical properties which differ from larger sized particles of

  2. White Mold of Chickpea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    White mold of chickpea can occur at either seedling stage or at flowering and pod filling stages. At seedling stage, the disease occurs at the base of the stem causing symptoms like collar rot. Often white mycelial growth around the stem on soil surface is visible. Affected plants wilt and die. ...

  3. White-Nose Syndrome

    NSDL National Science Digital Library

    Douglas Stemke (University of Indianapolis; )

    2011-04-28

    The Indiana Department of Natural Resource posted cave access restrictions sign at Clifty Falls State Park in southern Indiana in response to the lethal threat posed by White-Nose Syndrome to various cave-inhabiting bat species. White-Nose Syndrome is a bat disease that is still not well understood but is presumptively caused by the associated fungus Geomyces destructans.

  4. Sailing to White Boat

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a composite red-green-blue image of the rock called White Boat. It is the first rock target that Spirit drove to after finishing a series of investigations on the rock Adirondack. White Boat stood out to scientists due to its light color and more tabular shape compared to the dark, rounded rocks that surround it.

  5. Western White Pine

    USGS Multimedia Gallery

    A western white pine (Pinus monticola) in Kings Canyon National Park, Calif., towers over USGS ecologist Nathan Stephenson. Scientists analyzed data from 403 species of trees from around the world -- including western white pine (Pinus monticola), pictured here -- and learned that in general, a tre...

  6. White Flight: Some Hypotheses.

    ERIC Educational Resources Information Center

    Wegmann, Robert G.

    The available literature on white flight, or, more properly, school resegregation -- the phenomenon of white withdrawal (total or partial) from desegregated schools -- is reviewed in this paper which also reports some new research in this area. The distinction is made between those schools located on the fringes of the inner city, which first…

  7. Electronic Monitoring White Papers

    E-print Network

    Electronic Monitoring White Papers February 15, 2013 Source: NOAA Fisheries Office of Policy.holliday@noaa.gov #12;B-1 Appendix B - Electronic Monitoring White Paper Existing Technologies National Oceanic requirements, cost-effectiveness, available funding, and other criteria discussed in this paper. Electronic

  8. White Teachers Talking Race

    ERIC Educational Resources Information Center

    Segall, Avner; Garrett, James

    2013-01-01

    In light of the increasing racial diversity in American schools and the consistently homogenous teacher workforce in the United States, understanding the ways white teachers consider and attend to racial issues is of crucial importance to the educational landscape. This paper, based on a qualitative study, explores five white American…

  9. Whiteness and Critical Pedagogy

    ERIC Educational Resources Information Center

    Allen, Ricky Lee

    2004-01-01

    The purpose of this article is to rethink critical pedagogy by imagining it from a race-radical perspective that owes its lineage to scholars like W. E. B. Du Bois. The author assembles a critical pedagogy that hopes to contribute to both the transformation of white identity and the abolition of white supremacy. He draws from the roots of critical…

  10. White Dwarf Rotation: Observations and Theory

    E-print Network

    Steven D. Kawaler

    2003-01-27

    White dwarfs rotate. The angular momentum in single white dwarfs must originate early in the life of the star, but also must be modified (and perhaps severely modified) during the many stages of evolution between birth as a main--sequence star and final appearance as a white dwarf. Observational constraints on the rotation of single white dwarf stars come from traditional spectroscopy and from asteroseismology, with the latter providing hints of angular velocity with depth. Results of these observational determinations, that white dwarfs rotate with periods ranging from hours to days (or longer), tells us that the processes by which angular momentum is deposited and/or drained from the cores of AGB stars are complex. Still, one can place strong limits on these processes by considering relatively simple limiting cases for angular momentum evolution in prior stages, and on subsequent angular momentum evolution in the white dwarfs. These limiting-case constraints will be reviewed in the context of the available observations.

  11. Iron absorption from red and white wines.

    PubMed

    Bezwoda, W R; Torrance, J D; Bothwell, T H; Macphail, A P; Graham, B; Mills, W

    1985-02-01

    Iron (3 mg) was added as ferrous sulphate to 2 dl red wine, white wine and 7% alcohol and its absorption was then measured in 38 fasting male subjects. (The original concentrations of iron in the two wines were low, being 1.01-1.08 mg/l (red wine) and 0.13-0.20 (white wine]. The geometric mean absorption from red wine was only 20% of that from the alcohol solution whilst more than 4 times as much was absorbed from white wine as from the alcohol. Direct comparison showed greater absorption from white wine (10.4%) than from red wine (4.4%). Removal of about 80% of the polyphenols in red wine increased the geometric mean iron absorption from 1.9% to 3.6%. In vitro experiments indicated that iron was less soluble and less dialysable in red wines than in white wines. This was possibly due to the binding of iron to polyphenols in red wines. Electrophoretic studies suggested that the iron in white wines was complexed to hydroxycarboxylic acids. PMID:3975569

  12. Genome-Wide Analysis of Sorbitol Dehydrogenase (SDH) Genes and Their Differential Expression in Two Sand Pear (Pyrus pyrifolia) Fruits.

    PubMed

    Dai, Meisong; Shi, Zebin; Xu, Changjie

    2015-01-01

    Through RNA-seq of a mixed fruit sample, fourteen expressed sorbitol dehydrogenase (SDH) genes have been identified from sand pear (Pyrus pyrifolia Nakai). Comparative phylogenetic analysis of these PpySDHs with those from other plants supported the closest relationship of sand pear with Chinese white pear (P. bretschneideri). The expression levels varied greatly among members, and the strongest six (PpySDH2, PpySDH4, PpySDH8, PpySDH12, PpySDH13 and PpySDH14) accounted for 96% of total transcript abundance of PpySDHs. Tissue-specific expression of these six members was observed in nine tissues or organs of sand pear, with the greatest abundance found in functional leaf petioles, followed by the flesh of young fruit. Expression patterns of these six PpySDH genes during fruit development were analyzed in two sand pear cultivars, "Cuiguan" and "Cuiyu". Overall, expression of PpySDHs peaked twice, first at the fruitlet stage and again at or near harvest. The transcript abundance of PpySDHs was higher in "Cuiguan" than in "Cuiyu", accompanied by a higher content of sugars and higher ratio of fructose to sorbitol maintained in the former cultivar at harvest. In conclusion, it was suggested that multiple members of the SDH gene family are possibly involved in sand pear fruit development and sugar accumulation and may affect both the sugar amount and sugar composition. PMID:26068235

  13. Genome-Wide Analysis of Sorbitol Dehydrogenase (SDH) Genes and Their Differential Expression in Two Sand Pear (Pyrus pyrifolia) Fruits

    PubMed Central

    Dai, Meisong; Shi, Zebin; Xu, Changjie

    2015-01-01

    Through RNA-seq of a mixed fruit sample, fourteen expressed sorbitol dehydrogenase (SDH) genes have been identified from sand pear (Pyrus pyrifolia Nakai). Comparative phylogenetic analysis of these PpySDHs with those from other plants supported the closest relationship of sand pear with Chinese white pear (P. bretschneideri). The expression levels varied greatly among members, and the strongest six (PpySDH2, PpySDH4, PpySDH8, PpySDH12, PpySDH13 and PpySDH14) accounted for 96% of total transcript abundance of PpySDHs. Tissue-specific expression of these six members was observed in nine tissues or organs of sand pear, with the greatest abundance found in functional leaf petioles, followed by the flesh of young fruit. Expression patterns of these six PpySDH genes during fruit development were analyzed in two sand pear cultivars, “Cuiguan” and “Cuiyu”. Overall, expression of PpySDHs peaked twice, first at the fruitlet stage and again at or near harvest. The transcript abundance of PpySDHs was higher in “Cuiguan” than in “Cuiyu”, accompanied by a higher content of sugars and higher ratio of fructose to sorbitol maintained in the former cultivar at harvest. In conclusion, it was suggested that multiple members of the SDH gene family are possibly involved in sand pear fruit development and sugar accumulation and may affect both the sugar amount and sugar composition. PMID:26068235

  14. hp calculators HP 50g Complex numbers

    E-print Network

    Vetter, Frederick J.

    hp calculators HP 50g Complex numbers The MTH (MATH) menu The CMPLX (COMPLEX) menu Complex numbers Practice working problems involving complex numbers #12;hp calculators HP 50g Complex numbers hp calculators - 2 - HP 50g Complex numbers The MTH (MATH) menu The Math menu is accessed from the WHITE shifted

  15. Minimal model for aeolian sand dunes

    E-print Network

    Klaus Kroy; Gerd Sauermann; Hans J. Herrmann

    2002-03-02

    We present a minimal model for the formation and migration of aeolian sand dunes. It combines a perturbative description of the turbulent wind velocity field above the dune with a continuum saltation model that allows for saturation transients in the sand flux. The latter are shown to provide the characteristic length scale. The model can explain the origin of important features of dunes, such as the formation of a slip face, the broken scale invariance, and the existence of a minimum dune size. It also predicts the longitudinal shape and aspect ratio of dunes and heaps, their migration velocity and shape relaxation dynamics. Although the minimal model employs non-local expressions for the wind shear stress as well as for the sand flux, it is simple enough to serve as a very efficient tool for analytical and numerical investigations and to open up the way to simulations of large scale desert topographies.

  16. Sliding friction on wet and dry sand.

    PubMed

    Fall, A; Weber, B; Pakpour, M; Lenoir, N; Shahidzadeh, N; Fiscina, J; Wagner, C; Bonn, D

    2014-05-01

    We show experimentally that the sliding friction on sand is greatly reduced by the addition of some-but not too much-water. The formation of capillary water bridges increases the shear modulus of the sand, which facilitates the sliding. Too much water, on the other hand, makes the capillary bridges coalesce, resulting in a decrease of the modulus; in this case, we observe that the friction coefficient increases again. Our results, therefore, show that the friction coefficient is directly related to the shear modulus; this has important repercussions for the transport of granular materials. In addition, the polydispersity of the sand is shown to also have a large effect on the friction coefficient. PMID:24836256

  17. UV disinfection for onsite sand filter effluent

    SciTech Connect

    Lowery, J.D.; Romatzick, S.

    1982-05-01

    The technical and economic feasibility of using ultraviolet (uv) light as a viable alternative to chlorine as the required disinfectant for onsite sand filter effluents discharged to surface waters in Maine was determined. To obtain a reliable cross section of performance for sand filters in Maine, 74 filters were selected for an effluent characterization program. The effluent characterization study allowed general conclusions to be made with regard to the potential of uv disinfection. A simple suspended lamp uv disinfection unit was designed, constructed, and tested in the laboratory and in the field. The efficiency of the uv disinfection unit was determined through field testing at 10 of the 74 sand filter sites used in the effluent characterization program.

  18. Threshold for sand mobility on Mars calibrated from seasonal variations of sand flux.

    PubMed

    Ayoub, F; Avouac, J-P; Newman, C E; Richardson, M I; Lucas, A; Leprince, S; Bridges, N T

    2014-01-01

    Coupling between surface winds and saltation is a fundamental factor governing geological activity and climate on Mars. Saltation of sand is crucial for both erosion of the surface and dust lifting into the atmosphere. Wind tunnel experiments along with measurements from surface meteorology stations and modelling of wind speeds suggest that winds should only rarely move sand on Mars. However, evidence for currently active dune migration has recently accumulated. Crucially, the frequency of sand-moving events and the implied threshold wind stresses for saltation have remained unknown. Here we present detailed measurements of Nili Patera dune field based on High Resolution Imaging Science Experiment images, demonstrating that sand motion occurs daily throughout much of the year and that the resulting sand flux is strongly seasonal. Analysis of the seasonal sand flux variation suggests an effective threshold for sand motion for application to large-scale model wind fields (1-100?km scale) of ?(s)=0.01±0.0015?N?m(-2). PMID:25268931

  19. Ottawa Sand for Mechanics of Granular Materials (MGM) Experiment

    NASA Technical Reports Server (NTRS)

    2000-01-01

    What appear to be boulders fresh from a tumble down a mountain are really grains of Ottawa sand, a standard material used in civil engineering tests and also used in the Mechanics of Granular Materials (MGM) experiment. The craggy surface shows how sand grans have faces that can cause friction as they roll and slide against each other, or even causing sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. MGM uses the microgravity of space to simulate this behavior under conditions that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. These images are from an Electron Spectroscopy for Chemical Analysis (ESCA) study conducted by Dr. Binayak Panda of IITRI for Marshall Space Flight Center (MSFC). (Credit: NASA/MSFC)

  20. WMO Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS): Research Implementation Status

    NASA Astrophysics Data System (ADS)

    Nickovic, Slobodan; Barrie, Leonard

    2010-05-01

    Strong winds cause lifting of large amounts of sand and dust from bare, dry soils into the atmosphere. For countries in and downwind of arid regions, airborne sand and dust presents serious risks to the environment, property and human health. Impacts on health include respiratory and cardio-vascular problems, eye infections and in some regions, diseases such as meningitis and valley fever. Dust can efficiently carry irritating spores, bacteria, viruses and persistent organic pollutants. It can also efficiently transport nutrients to parts of the world oceans and affect marine biomass production. Other impacts include negative effects on the ground transport, aviation, agriculture and visibility. The Inter-governmental Panel on Climate Change (IPCC) recognizes dust as a major component of the atmospheric aerosol that is an essential climate variable. Dust aerosol has important effects on weather through feedback on atmospheric dynamics, clouds and precipitation formation. Approximately 15 centres around the world provide sand and dust research operational forecasts. Many are operated by national meteorological services of the World Meteorological Organization (WMO). Sand and dust storm models can substantially reduce risk by providing dust concentration predictions for several days in advance. Numerical weather prediction systems that drive these models use complex parameterizations and assimilation of satellite, and surface-based observations to predict winds, clouds, precipitation and dust mobilization, transport, and removal from the atmosphere. Sand and dust forecast products contribute to the mitigation and reduction of risk through research based advances in understanding and forecasting products. Observations of sand and dust are made by many agencies and some of them are being coordinated globally through the WMO Global Atmosphere Watch (GAW) programme. In 2006, WMO and partners initiated the implementation of the Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS) in order to improve the capabilities of countries affected by dust to reduce risks associated with airborne sand and dust. This project is in response to the desire of more than 40 WMO member countries to improve capabilities for more reliable sand and dust storm forecasts. The project has strong crosscutting features: it relies on real-time delivery of products; it integrates research communities (modelling, observation groups, and effects) and communities of practice (e.g. medical, aeronautical, agricultural users). There are two already established SDS-WAS nodes (Asian and North-Africa-Europe-Middle East) that coordinate implementation of the project objectives at regional levels. This presentation will review current status and future steps in the project implementation.

  1. Paleo-piracy endangers Vendian (Ediacaran) fossils in the White Sea - Arkhangelsk region of Russia (Les prélèvements sauvages, une menace pour les fossiles vendiens (édiacariens) de la région de la Mer Blanche - Arkhangelsk en Russie)

    Microsoft Academic Search

    Mikhail A. FEDONKIN; Andrey Yu. IVANTSOV; Maxim V. LEONOV; Jere H. LIPPS; Eugeniy I. MALYUTIN; Yuriy V. KHAN

    The world-famous Vendian (Ediacaran) fossil biota in the White Sea - Arkhangelsk region of Russia contains some of the most exquisite fossils of the earliest macrobiota (560-545 million years old) on Earth. Over 600m of continuously fossiliferous strata consisting of fine sand, silt and mud crop out at many localities along the White Sea. The fossils have been under study

  2. An added dimension: GC atmospheric pressure chemical ionization FTICR MS and the Athabasca oil sands.

    PubMed

    Barrow, Mark P; Peru, Kerry M; Headley, John V

    2014-08-19

    The Athabasca oil sands industry, an alternative source of petroleum, uses large quantities of water during processing of the oil sands. In keeping with Canadian environmental policy, the processed water cannot be released to natural waters and is thus retained on-site in large tailings ponds. There is an increasing need for further development of analytical methods for environmental monitoring. The following details the first example of the application of gas chromatography atmospheric pressure chemical ionization Fourier transform ion cyclotron resonance mass spectrometry (GC-APCI-FTICR MS) for the study of environmental samples from the Athabasca region of Canada. APCI offers the advantages of reduced fragmentation compared to other ionization methods and is also more amenable to compounds that are inaccessible by electrospray ionization. The combination of GC with ultrahigh resolution mass spectrometry can improve the characterization of complex mixtures where components cannot be resolved by GC alone. This, in turn, affords the ability to monitor extracted ion chromatograms for components of the same nominal mass and isomers in the complex mixtures. The proof of concept work described here is based upon the characterization of one oil sands process water sample and two groundwater samples in the area of oil sands activity. Using the new method, the Ox and OxS compound classes predominated, with OxS classes being particularly relevant to the oil sands industry. The potential to resolve retention times for individual components within the complex mixture, highlighting contributions from isomers, and to characterize retention time profiles for homologous series is shown, in addition to the ability to follow profiles of double bond equivalents and carbon number for a compound class as a function of retention time. The method is shown to be well-suited for environmental forensics. PMID:25036898

  3. High temperature thermal energy storage in moving sand

    Microsoft Academic Search

    R. H. Turner; H. I. Awaya

    1978-01-01

    Several high-temperature (to 500 C) heat-storage systems using sand as the storage medium are described. The advantages of sand as a storage medium include low cost for sand, widespread availability, non-toxicity, non-degradation characteristics, easy containment, and safety. The systems considered include: stationary sand with closely spaced tubes throughout the volume, the use of a fluidized bed, use of conveyor belt

  4. Tar sand and heavy oil resources and technology

    Microsoft Academic Search

    1972-01-01

    Tar-sand resources in the U.S. are not as concentrated as the Canadian Athabasca deposits, but they are significant; the amount recoverable is estimated to be 25 to 35 billion barrels. Some of the characteristics of tar sands and heavy oil sands and their occurrence are discussed. The single large-scale production of bitumen from tar sands is the operation of Great

  5. 22. INTERIOR VIEW WITH INTERIOR VIEW OF MOLDING SANDS CONTROL ...

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

    22. INTERIOR VIEW WITH INTERIOR VIEW OF MOLDING SANDS CONTROL AND TEST LAB FOR UNIT NO. 2 GREY IRON DISAMATIC. SAND CASTING TECHNICIAN, ROY BATES, TESTS THE WEIGHT OF THE SAND, DRYS IT, AND WEIGHT IT AGAINST STANDARDS TO CALCULATE THE CORRECT MOISTURE NEEDED FOR DIFFERENT MOLDS. THE SAND MIX VARY WITH THE SIZE AND COMPOSITION OF THE CASTING. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  6. Atlantic White Cedar Website

    NSDL National Science Digital Library

    Aimlee Laderman

    This website, created by Dr. Aimlee Laderman, is dedicated to the knowledge and awareness of Atlantic White Cedar (AWC) Swamps. It includes an image of Atlantic White Cedar and links to two online resources: The Ecology of Atlantic White Cedar Wetlands: A Community Profile; and AWC Flora: Flora Associated with Atlantic White Cedars. The Community Profile describes the AWC and the bogs and swamps it dominates or co-dominates throughout its range. Topics discussed include interrelationships with other habitats, putative origins and migration patterns, substrate biogeochemistry, associated plant and animal species, and impacts of both natural and anthropogenic disturbance. The AWC Flora is a database that records the taxonomy, accepted scientific and common genus, species, and family names; synonomy, habit, habitat types, and the states in which each species is known to have been found in AWC wetlands. Filemake Pro is needed to view this resource.

  7. Ryan White Program

    MedlinePLUS

    ... Estimates for Appropriations Committees, FY 2013. ? Return to text HRSA. The Ryan White HIV/AIDS Program Progress ... 2012: Ahead of the Curve ; 2012. ? Return to text The term “state” used in this fact sheet ...

  8. Above and below-ground growth of white spruce seedlings with roots divided into different substrates with or without controlled-release fertilizer

    Microsoft Academic Search

    M. J. Krasowski; J. N. Owens; L. E. Tackaberry; H. B. Massicotte

    1999-01-01

    Thirty-two one-year-old white spruce (Picea glauca (Moench) Voss) seedlings were grown outdoors for one season in 35 L pots\\u000a buried in the soil. The pots were vertically split in half. One compartment (mineral) was filled with loamy sand. The bottom\\u000a of the other compartment (organic) was filled with 10 cm sand topped with 15 cm of organic substrates. Two seedling

  9. SANDIA REPORT SAND930731 s UC706

    E-print Network

    Kansas, University of

    March 1993 Distribution Category UC-706 Spaceborne SAR Study: LDRD '92 Final Report D. L. Bickel RadarSANDIA REPORT SAND93­0731 s UC­706 Unlimited Release Printed March 1993 Spaceborne SAR Study: LDRD Development Department Sandia National Laboratories Albuquerque, New Mexico 87185 C. T. Allen Radar & Antenna

  10. SANDIA REPORT SAND99-2953

    E-print Network

    SANDIA REPORT SAND99-2953 Unlimited Release Printed November 1999 a Shaped-Charge Parallel-2953 Unlimited Release Printed November 1999 The Optimization of a Shaped-Charge Design Using Parallel Computers of the modeled system. Using a shaped-charge jet design as an archetypal test case and the CTH parallel shock

  11. Western gas sands project. Status report

    Microsoft Academic Search

    1978-01-01

    The progress during January, 1978 of the major government sponsored endeavors undertaken to increase gas production from the low permeability gas sands of the western United States is summarized. A core program meeting was held on January 25, 1978 at the CER Corporation office in Las Vegas, Nevada. The core tasks to be performed on the available core supply were

  12. The sands of time and tidal friction

    Microsoft Academic Search

    Leslie V. Morrison; F. Richard Stephenson

    1998-01-01

    Ancient Babylonian clay tablets buried for centuries beneath the sands of the desert are part of an extensive historical archive which contains vital information about the rotation of the Earth. Many are preserved, and using these seemingly crude ancient and medieval observations of eclipses, variations in the Earth's rotation can be traced back over the past 2500 years. The tidal

  13. SOURCE ASSESSMENT: TRANSPORT OF SAND AND GRAVEL

    EPA Science Inventory

    This report describes a study of atmospheric emissions from the transport of sand and gravel on unpaved roads. The potential environmental effect of this emission source was evaluated using source severity, defined as the ratio of the time-averaged maximum ground level concentrat...

  14. The strength and dilatancy of sands

    Microsoft Academic Search

    M. D. Bolton

    1986-01-01

    Extensive data of the strength and dilatancy of 17 sands in axisymmetric or plane strain at different densities and confining pressures are collated. The critical state angle of shearing resistance of soil which is shearing at con- stant volume is principally a function of mineralogy and can readily be determined experimentally within a margin of about l\\

  15. TOXOPLASMOSIS IN SAND FOX (VULPUS RUEPPELLII)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatal toxoplasmosis was diagnosed in a sand fox (Vulpes rueppelli) from United Arab Emirates. Toxoplasma gondii-like tachyzoites were found associated with necrosis in intestine, spleen, liver, pancreas, lungs, mesenteric lymph nodes, and the heart. Ttachyzoites reacted positively with T. gondii-spe...

  16. Steamflood experiment in a Utah tar sand

    SciTech Connect

    Johnson, L.A. Jr.; Fahy, L.J.; Romanowski, L.J. Jr.

    1981-01-01

    The first Laramie Energy Technology Center steamflood experiment in a Utah Tar Sand, LETC TS-1S, was conducted in the Northwest Asphalt Ridge deposit located near Vernal, Utah. Following completion of construction in April 1980, steam injection was initiated in the center well of two concentric inverted five spot patterns. 8 refs.

  17. Canada's First Commercial Tar Sand Development

    Microsoft Academic Search

    E. D. Innes; V Fear

    1967-01-01

    Following a brief introduction to the Great Canadian Oil Sands Limited project, the paper describes the specific technical problems faced in planning for commercial production. An overall plant flow sheet, material balance, and summary of energy requirements are presented. Topics discussed under the heading of mining and solids transport include the geological evaluation program, the overburden removal program, year-round-mining procedures,

  18. The Early Years: Building With Sand

    NSDL National Science Digital Library

    Peggy Ashbrook

    2010-03-01

    Children playing in damp sand invariably try to make a tower or a tunnel. By providing experiences with a variety of materials, alone and together, teachers set up the conditions for children to learn through their senses and ensure that a class approache

  19. NU Intramural Sports Sand Dodgeball Rules

    E-print Network

    Sridhar, Srinivas

    NU Intramural Sports Sand Dodgeball Rules GENERAL RULES: 1. All players must present their valid identification card. 2. Jewelry is not allowed to be worn by any participant during an Intramural event. Any with a band-aid. 3. GAME TIME IS FORFEIT TIME! The minimum number of players must have their Husky Cards

  20. Wind-Blown Sand: Threshold of Motion 

    E-print Network

    Swann, Christy Michelle

    2014-11-12

    The fluid threshold for wind-blown sand is the minimum shear velocity required to initiate grain movement by the force of the wind alone, and is used to predict dust emission and landform change in sandy environments. R.A. ...

  1. Air-pollution-induced foliar injury to natural populations of jack and white pine in a chronically polluted environment

    Microsoft Academic Search

    Thomas V. Armentano; Eric S. Menges

    1987-01-01

    Air-pollution-induced foliar injury was determined for natural populations of jack pine (Pinus banksiana) and white pine (P. strobus) on Lake Michigan sand dunes in Indiana. Chlorotic mottle and tip necrosis were found in all populations and one or both symptoms appeared in most trees. However, considering the proximity of the populations to pollution sources, foliar injury levels were notably low.

  2. White Students' Understanding of Race: An Exploration of How White University Students, Raised in a Predominately White State, Experience Whiteness

    ERIC Educational Resources Information Center

    Smith, Barbara A.

    2014-01-01

    This study examines White university students' understanding of race. Based in the scholarship on higher education and diversity, and framed in Critical Race Theory (CRT), this study explores the racial awareness of White students. This study contributes to the literature on the racial experience of Whites and an understanding of how White

  3. An overview of Canadian oil sand mega projects

    Microsoft Academic Search

    R. Paes; M. Throckmorton

    2008-01-01

    There are currently a number of existing oil sand Mega-Projects as well as many other related projects planned and under construction in the Alberta oil sands region. There are many challenges facing the oil sands. The demanding climate conditions cost of extraction, environmental, energy constraints as well as the rising construction costs are examples. To develop this huge petroleum reserve,

  4. Plant Availability of Metals in Waste Foundry Sands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foundries in the United States generate several million tons of waste sand each year. These sands are no longer suitable for metalcasting processes, and about 90% are discarded in landfills. However, the majority of these waste foundry sands (WFSs) qualify as non-hazardous industrial waste and the...

  5. George Sand et les arts du XVIIIe Introduction

    E-print Network

    Paris-Sud XI, Université de

    George Sand et les arts du XVIIIe siècle Introduction Olivier Bara (Université Lyon 2, UMR LIRE) Le présent numéro des Amis de George Sand est issu d'un séminaire organisé par l'université Lyon 2 et l'UMR LIRE, de 2008 à 2012, intitulé « George Sand et les arts du XVIIIe siècle ». Les articles ici réunis

  6. DRIVEN PIPE PILES IN DENSE SAND BYRON BYRNE

    E-print Network

    Byrne, Byron

    DRIVEN PIPE PILES IN DENSE SAND BYRON BYRNE GEOMECHANICS GROUP THE UNIVERSITY OF WESTERN AUSTRALIA #12;Driven Pipe Piles in Dense Sand Byron Byrne Geomechanics Group The University of Western Australia Page 1 ABSTRACT: Piles are often driven open ended into dense sand with the aim of increasing the ease

  7. Stable Dynamics of Sand Automata Alberto Dennunzio1

    E-print Network

    Paris-Sud XI, Université de

    Stable Dynamics of Sand Automata Alberto Dennunzio1 , Pierre Guillon2 , and Benoît Masson3 1.masson@lif.univ-mrs.fr Abstract. In this paper, we study different notions of stability of sand automata, dynamical systems systems [10]. In [3], the authors introduced sand automata as a generalization of sandpile models

  8. Modelling of reoxidation inclusion formation in steel sand casting

    E-print Network

    Beckermann, Christoph

    Modelling of reoxidation inclusion formation in steel sand casting A. J. Melendez, K. D. Carlson pouring, as well as their final locations on the surface of steel sand castings. Inclusions originate by comparing the simulation results to measurements made on production steel sand castings. Good overall

  9. Biocalcification of Sand through Ureolysis Chiung-Wen Chou1

    E-print Network

    Aydilek, Ahmet

    Biocalcification of Sand through Ureolysis Chiung-Wen Chou1 ; Eric A. Seagren, A.M.ASCE2 ; Ahmet H. A laboratory study was conducted to evaluate the changes in geomechanical properties of sand attributable. pasteurii). Specifically, direct shear and California Bearing Ratio (CBR) tests were conducted on sand

  10. BEHAVIOR OF A SAND RIDGE MODEL Juan Mario Restrepo

    E-print Network

    Soatto, Stefano

    BEHAVIOR OF A SAND RIDGE MODEL Juan Mario Restrepo Mathematics Department University of California, Los Angeles Los Angeles, CA 90095 Abstract. A model for the formation and evolution of longshore sand waves, which are represented by wave packets, and a sandy bottom topography, conspire to produce sand

  11. Texas Tech University Sand Volleyball Recreational Sports League

    E-print Network

    Gelfond, Michael

    Texas Tech University Sand Volleyball Recreational Sports League T 806.742.2945 | www.recsports.ttu.edu | SRC Room 203 When: League Play starts on Monday, April 15 Where: Rec Sports Sand Volleyball Courts end at 13, so if tied at 12-12, next point wins) Shoes are not permitted for competition on sand

  12. Performance of Shallow Foundations on Sand B.W. Byrne.

    E-print Network

    Byrne, Byron

    Performance of Shallow Foundations on Sand B.W. Byrne. Department of Engineering Science hardening plasticity theory. The testing to date has mainly used high friction angle samples of sand to imitate typical offshore conditions (in the North Sea for example). Dry sand has been used so that long

  13. SHORT COMMUNICATION First Collection Records of Phlebotomine Sand Flies (Diptera

    E-print Network

    SHORT COMMUNICATION First Collection Records of Phlebotomine Sand Flies (Diptera: Psychodidae) From (2011); DOI: 10.1603/ME10170 ABSTRACT The phlebotomine sand Ã?ies Lutzomyia (Psathyromyia) shannoni (Dyar for either species. KEY WORDS phlebotomine, sand Ã?y, leishmaniasis, Lutzomyia shannoni, Lutzomyia vexator

  14. Channel bed evolution and sediment transport under declining sand inputs

    E-print Network

    Montgomery, David R.

    Channel bed evolution and sediment transport under declining sand inputs Karen B. Gran,1,2 David R structure development and sediment transport as sand inputs decline. On the Pasig-Potrero River, we investigated channel recovery following emplacement of sand-rich pyroclastic deposits in the 1991 eruption

  15. Contact With Beach Sand Among Beachgoers and Risk of Illness

    Microsoft Academic Search

    Christopher D. Heaney; Elizabeth Sams; Steve Wing; Steve Marshall; Kristen Brenner; Alfred P. Dufour; Timothy J. Wade

    2009-01-01

    Recent studies of beach sand fecal contamination have triggered interest among scientists and in the media. Although evidence shows that beach sand can harbor high concentrations of fecal indicator organisms, as well as fecal pathogens, illness risk associated with beach sand contact is not well understood. Beach visitors at 7 US beaches were enrolled in the National Epidemiological and Environmental

  16. BMM SEPARATION SCREEN PERMITS SAND TO PASS TO BELT CONVEYORS ...

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

    BMM SEPARATION SCREEN PERMITS SAND TO PASS TO BELT CONVEYORS BELOW THAT TRANSPORT THE SAND BACK TO STORAGE AND RECONDITIONING BINS WHILE CASTINGS ARE TRANSPORTED ON ADDITIONAL VIBRATING CONVEYORS TO DEGATING AREAS. - Southern Ductile Casting Company, Shaking, Degating & Sand Systems, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  17. Improving the method of preparation of molding sand

    Microsoft Academic Search

    A. A. Markov

    1985-01-01

    nology an improved method of preparation of molding sand has been developed and it has been introduced in Rakitnoe Fitting Plant. Means of mechanization providing the obtaining of the optimum stable properties and composition of the original materials and the finished sand have been designed and built. After shakeout from the casting molds the return (burnt) sand is fed by

  18. The 3-D spread of saltation sand over a flat bed surface in aeolian sand transport

    Microsoft Academic Search

    Bin Yang; Yuan Wang; Yang Zhang

    2009-01-01

    This paper investigated the 3-D motion of saltation sand by high-speed photography and stereo particle image velocimetry (SPIV). By the high-speed camera, the sand particle trajectories in the transverse plane near bed surface have been obtained. It could be found that the collision between the particle and the bed surface would in principle cause the transverse motion of the particle

  19. Great Canadian Oil Sands experience in the commercial processing of Athabasca Tar Sands

    Microsoft Academic Search

    G. F. Andrews; H. M. Lewis; E. W. Dobson

    1968-01-01

    A brief review is given of the history of the Great Canadian Oil Sands (G.C.O.S.) project to recover 45,000 bpd of synthetic crude oil from the Athabasca Tar Sands by open pit mining, hot water extraction, coking, and hydrorefining. This paper then discusses the startup and initial operation of the G.C.O.S. plant. Emphasis is directed toward actual vs. design performance

  20. Drag reduction using superhydrophobic sanded Teflon surfaces

    NASA Astrophysics Data System (ADS)

    Song, Dong; Daniello, Robert J.; Rothstein, Jonathan P.

    2014-08-01

    In this paper, a series of experiments are presented which demonstrate drag reduction for the laminar flow of water through microchannels using superhydrophobic surfaces with random surface microstructure. These superhydrophobic surfaces were fabricated with a simple, inexpensive technique of sanding polytetrafluoroethylene (PTFE) with sandpaper having grit sizes between 120- and 600-grit. A microfluidic device was used to measure the pressure drop as a function of the flow rate to determine the drag reduction and slip length of each surface. A maximum pressure drop reduction of 27 % and a maximum apparent slip length of b = 20 ?m were obtained for the superhydrophobic surfaces created by sanding PTFE with a 240-grit sandpaper. The pressure drop reduction and slip length were found to increase with increasing mean particle size of the sandpaper up to 240-grit. Beyond that grit size, increasing the pitch of the surface roughness was found to cause the interface to transition from the Cassie-Baxter state to the Wenzel state. This transition was observed both as an increase in the contact angle hysteresis and simultaneously as a reduction in the pressure drop reduction. For these randomly rough surfaces, a correlation between the slip length and the contact angle hysteresis was found. The surfaces with the smallest contact angle hysteresis were found to also have the largest slip length. Finally, a number of sanding protocols were tested by sanding preferentially along the flow direction, across the flow direction and with a random circular pattern. In all cases, sanding in the flow direction was found to produce the largest pressure drop reduction.

  1. Imaging of Acoustic Waves in Sand

    SciTech Connect

    Deason, Vance Albert; Telschow, Kenneth Louis; Watson, Scott Marshall

    2003-08-01

    There is considerable interest in detecting objects such as landmines shallowly buried in loose earth or sand. Various techniques involving microwave, acoustic, thermal and magnetic sensors have been used to detect such objects. Acoustic and microwave sensors have shown promise, especially if used together. In most cases, the sensor package is scanned over an area to eventually build up an image or map of anomalies. We are proposing an alternate, acoustic method that directly provides an image of acoustic waves in sand or soil, and their interaction with buried objects. The INEEL Laser Ultrasonic Camera utilizes dynamic holography within photorefractive recording materials. This permits one to image and demodulate acoustic waves on surfaces in real time, without scanning. A video image is produced where intensity is directly and linearly proportional to surface motion. Both specular and diffusely reflecting surfaces can be accomodated and surface motion as small as 0.1 nm can be quantitatively detected. This system was used to directly image acoustic surface waves in sand as well as in solid objects. Waves as frequencies of 16 kHz were generated using modified acoustic speakers. These waves were directed through sand toward partially buried objects. The sand container was not on a vibration isolation table, but sat on the lab floor. Interaction of wavefronts with buried objects showed reflection, diffraction and interference effects that could provide clues to location and characteristics of buried objects. Although results are preliminary, success in this effort suggests that this method could be applied to detection of buried landmines or other near-surface items such as pipes and tanks.

  2. Investigation of the sand sea with the tallest dunes on Earth: China's Badain Jaran Sand Sea

    NASA Astrophysics Data System (ADS)

    Dong, Zhibao; Qian, Guangqiang; Lv, Ping; Hu, Guangyin

    2013-05-01

    China's Badain Jaran Sand Sea features the tallest dunes on Earth and a unique mega-dune-lake landscape. It had been explored little until the 1990s, though early scientific explorations surrounding the sand sea had begun by the early 20th century. Heated debates now focus on the desert environment, and particularly how the mega-dunes and desert lakes develop and evolve. This paper reviews the status of these debates and summarizes the supporting evidences. The environmental research mainly concerns formation and evolution of the sand sea, and its relationship with climate change. The proposed formation time ranges from the Early Pleistocene to the Holocene. Opinions vary about climate change on different time scales. The reconstructed climate change history is shorter than the sand sea's history, with the longest record extending to the Late Pleistocene. The mega-dune research focuses on sediments, dune morphology, and formation processes. It remains unclear whether the mega-dunes result primarily from wind action, control by the underlying topography, or groundwater maintenance. The sources of lake water are also debated, but there are four main hypotheses: atmospheric precipitation, groundwater from nearby areas, precipitation and snowmelt in remote areas such as the Qilian Mountains and the Qinghai-Tibetan Plateau, or paleowater that formed during past periods of wet climate. We believe that the sand sea deserves further study in terms of its dune geomorphology, evolution, and hydrology, and their responses to climate change. Meteorological and hydrological observations and monitoring in the sand sea are particularly necessary.

  3. Experimental investigation of cephapirin adsorption to quartz filter sands and dune sands

    NASA Astrophysics Data System (ADS)

    Peterson, Jonathan W.; O'Meara, Theresa A.; Seymour, Michael D.

    2008-08-01

    Batch experiments were performed to investigate cephapirin (a widely used veterinary antibiotic) adsorption on various size sands of low total organic carbon content (0.08-0.36 wt%). In the aqueous concentration range investigated (11-112 ?mol/L cephapirin), adsorption to nearly pure quartz filter sands (0.50-3.35 mm diameter) is low. Isotherms are S-shaped and most display a region of minimum adsorption, where decreased adsorption occurs with increasing solution concentration, followed by increased adsorption at higher concentrations. Cephapirin adsorption to quartz-rich, feldspar-bearing dune sands (0.06-0.35 mm diameter), and the smallest quartz filter sand investigated (0.43-0.50 mm), can be described by linear sorption isotherms over the range of concentrations investigated. Distribution coefficients ( K d) range from 0.94 to 3.45 L/kg. No systematic relationship exists between grain size and amount of adsorption for any of the sands investigated. Cephapirin adsorption is positively correlated to the feldspar ratio (K-feldspar/(albite + Ca-plagioclase). Feldspar-ratio normalization of distribution coefficients was more effective than organic carbon normalization at reducing variability of K d values in the dune sands investigated.

  4. Efficacy of Different Sampling Methods of Sand Flies (Diptera: Psychodidae) in Endemic Focus of Cutaneous Leishmaniasis in Kashan District, Isfahan Province, Iran

    PubMed Central

    Hesam-Mohammadi, Marzieh; Rassi, Yavar; Abai, Mohammad Reza; Akhavan, Amir Ahmad; Karimi, Fatemeh; Rafizadeh, Sina; Sanei-Dehkordi, Alireza; Sharafkhah, Maryam

    2014-01-01

    Background: The aim of the study was to evaluate and compare the efficiency and practicality of seven trapping methods for adult phlebotominae sand flies. The results of this investigation provide information to determine the species composition and nocturnal activity pattern of different sand fly species. Methods: The study was carried out in both plain region (about 5km far from northeast) and mountainous region (about 40km far from southwest of Kashan City). Seven traps were selected as sampling methods and sand flies were collected during 5 interval times starting July to September 2011 and from 8:00PM to 6:00AM in outdoors habitats. The traps include: sticky traps (4 papers for 2 hours), Disney trap, Malaise, CDC and CO2 light traps, Shannon traps (black and white nets) and animal-baited trap. Results: A total of 1445 sand flies belonging to 15 species of Phlebotomus spp. and five of Sergentomyia spp. were collected. Females and males comprised 44.91% and 55.09% of catches, respectively. Of the collected specimens, Se. sintoni was found to be the most prevalent (37.86%) species, while Ph. papatasi, accounted for 31.76% of the sand flies. Conclusion: Disney trap and sticky traps exhibited the most productivity than other traps. In addition, in terms of the efficiency of sampling method, these two trapping methods appeared to be the most productive for both estimating the number of sand flies and the species composition in the study area.

  5. THE SIMULATION OF WIND-BLOWN SAND MOVEMENT AND PROBABILITY DENSITY FUNCTION OF LIFT-OFF VELOCITIES OF SAND GRAINS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurately describing the probability density function (PDF) of lift-off or initial velocities of wind-blown sand ejecting from a sand bed is fundamental to understanding the mechanisms of wind-blown sand movement. Our objective was to investigate the efficacy of developing the PDF of lift-off veloc...

  6. 3D seismic, geochemical and biostratigraphical analysis of Paleogene remobilized sand in the Norwegian-Danish Basin

    NASA Astrophysics Data System (ADS)

    Andresen, Katrine Juul; Rønø Clausen, Ole; Heilmann-Clausen, Claus; Friis, Henrik

    2013-04-01

    This study describes remobilized Paleogene sand occurring on the hanging-wall segment north of the major D-1 normal fault in the Norwegian-Danish Basin, eastern North Sea. The remobilized sand is observed on 3D seismic data in fine-grained Eocene host-strata as cross-cutting reflections with a typical tabular, V-shaped or wing-like geometry in the seismic cross-sections and a pronounced jack-up of the overlying succession onto which onlap can be observed. In map view the remobilized sand in certain areas have a channel-like appearance. The seismic observations indicate that the sand has a remobilized origin which may be partly depositional. Particularly the observed wings and jack-up on the seismic cross-sections indicate remobilization which potentially could be generated by two different processes: a) remobilization of depositional channel sand resulting in the formation of injected wings along the sides of the channel, or b) injection of remobilized sand from the deeper Paleocene strata causing jack-up and typically V-shaped intrusions. Injection of Paleocene sand into Eocene host strata is a well-known phenomenon from the nearby Paleogene Siri Canyon located c. 15 km north of the study area. In order to acquire more information about the intrusions a geochemical study and a detailed biostratigraphical dating of cuttings and sidewall core samples from the Floki-1 well was carried out. The Floki-1 well penetrates the remobilized sand and was drilled to test an apparent 4-way closure on prospect Eocene sand which by then was interpreted to be 100 % depositional. The geochemical study of the samples from the sand identified the Floki-sandstone as a very fine grained sand and silt with a matrix of very angular silt grains. The sand does not contain clays. The matrix appears to have formed by crushing of the sand grains. Thus, heavy minerals appear to have disintegrated by crushing but still most parts of the mineral grain is found together. Glauconite grains are strongly smeared. The sorting pattern, and the angular shape of silt sized matrix grains, and the intense shearing and deformation of glauconite grains indicates that the sand may have been injected under high pressure, resulting in massive crushing of detrital grains. The age dating mainly includes dinocysts analysis from seven sidewall core samples and nine cutting samples above, within and below the sand. It is expected that the sand should either be of Eocene age probably revealing a depositional origin with subsequent remobilization to the sides (process a), or a Paleocene age revealing injection from the deeper strata (process b). In order to address all observations, a potential model of generation may include elements of depositional sand combined with up-, downward and/or lateral injection which could have been facilitated by intense activity in the nearby D-1 fault. The study highlights the importance of interdisciplinary approaches in the interpretation of complex geological features formed by several geological processes and mechanisms.

  7. Transient Lectin Binding by White Matter Tract Border Zone Microglia in the Foetal Rabbit Brain

    Microsoft Academic Search

    W. Thomas Bass; Gerard A. Singer; Francis J. Liuzzi

    1998-01-01

    Axonal growth cones of developing white matter tracts are guided through the cerebrum by interactions with cell surface and extracellular matrix molecules expressed by glial cells that mediate cell adhesion and contact-dependent inhibition. Specific carbohydrates are considered essential for the proper functioning of these molecular complexes. We studied developmental aspects of complex carbohydrate expression by white matter glia in the

  8. The importance of bed sediment sand content for the structure of a static armor layer in a gravel bed river

    NASA Astrophysics Data System (ADS)

    Curran, Joanna Crowe; Waters, Kevin A.

    2014-07-01

    The surface structure of static armor layers generated from water-worked gravel bed channels was investigated with primary focus on the influence of sand content and flow rate. Flume experiments were conducted in which four sediment mixtures with sand contents between 1% and 38% were armored under one of three different flow rates. First- and second-order statistical analyses were applied to digital elevation models of unarmored, armored, and clustered bed surface areas to identify changes in surface structure. Results were combined with data from previous research to create an extended data set of armored bed surfaces. Water-worked, unarmored bed surfaces established under a dynamic equilibrium flow rate impacted the topographic variability and structure of the armored beds. Surface complexity decreased with armor formation as surface grains preferentially aligned with the flow direction. The bed surface became smoother, and where sediment mixture sand content was constant, there was greater smoothing of the surface during higher armoring flows as grains rearranged more easily. As bulk sand content increased, statistical analyses of the expanded data set showed that beds with very little sand content developed static armor layers that remained rough and had greater topographic variability than armor layers from sediments with higher sand contents. The bulk sediment sand content exerted a stronger influence over the change in surface roughness and structure upon armoring than that of the flow rate during armor formation. When combined with the knowledge of the local flow regime, the sand content may aid in predictions related to armored bed surface structure.

  9. Method for filtering solvent and tar sand mixtures

    SciTech Connect

    Kelterborn, J. C.; Stone, R. A.

    1985-09-03

    A method for filtering spent tar sands from a bitumen and organic solvent solution comprises separating the solution into two streams wherein the bulk of the coarser spent tar sand is in a first stream and has an average particle size of about 10 to about 100 mesh and the bulk of the finer spent tar sand is in a second stream; producing a filter cake by filtering the coarser spent tar sand from the first stream; and filtering the finer spent tar sand from the second stream with the filter cake. The method is particularly useful for filtering solutions of bitumen extracted from bitumen containing diatomite, spent diatomite and organic solvent.

  10. The physics of wind-blown sand and dust

    E-print Network

    Jasper F. Kok; Eric J. R. Parteli; Timothy I. Michaels; Diana Bou Karam

    2012-09-20

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This article presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  11. Laboratory and field evaluation of an underwater sand height gage

    NASA Technical Reports Server (NTRS)

    Swift, D. J. P.; Mcgrath, D. G.

    1972-01-01

    An underwater sand height gage was investigated. This instrument consisted of two transducers, one screened and one unscreened. Laboratory experimentation included static and dynamic tests with three test sands--fine, medium, and coarse. Field tests were conducted at Rudee Inlet, Virginia Beach, Virginia. Test results showed a linear response to up to 10 inches of sand loading. Deviation observed in identical tests appeared to be due to variation in the density of sand. Density differences reflected varying packing styles which, in turn, were a consequence of grain size and flow regime. Further evaluations of the sand height gage reflect this instrument's potential.

  12. The physics of wind-blown sand and dust

    E-print Network

    Kok, Jasper F; Michaels, Timothy I; Karam, Diana Bou

    2012-01-01

    The transport of dust and sand by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This article presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  13. The physics of wind-blown sand and dust

    NASA Astrophysics Data System (ADS)

    Kok, Jasper F.; Parteli, Eric J. R.; Michaels, Timothy I.; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  14. Incorporation of CrusHed Sands and Tunisian Desert Sands in the Composition of Self Compacting Concretes Part I: Study of Formulation

    Microsoft Academic Search

    Abdelhamid Rmili; Mongi Ben Ouezdou; Mhamed Added; Elhem Ghorbel

    2009-01-01

    This paper examines the incorporation of the crushed sand (CS) and desert sand (DS) in the formation of self compacting con- crete (SCC). These sands have been substituted for the rolled sand (RS), which is currently the only sand used in concretes and which is likely to run out in our country. DS, which comes from the Tunisian Sahara in

  15. Characterization of naphthenic acids in oil sands wastewaters by gas chromatography-mass spectrometry

    Microsoft Academic Search

    Fervone M Holowenko; Michael D MacKinnon; Phillip M Fedorak

    2002-01-01

    The water produced during the extraction of bitumen from oil sands is toxic to aquatic organisms due largely to a group of naturally occurring organic acids, naphthenic acids (NAs), that are solubilized from the bitumen during processing. NAs are a complex mixture of alkyl-substituted acyclic and cycloaliphatic carboxylic acids, with the general chemical formula CnH2n+ZO2, where n is the carbon

  16. Case history of Yakin Field: its development and sand control

    SciTech Connect

    Sawolo, N.; Krueger, R.F.; Maly, G.P.

    1982-01-01

    This study deals with the development of the Yakin Field in E. Kalimantan, Indonesia, with emphasis on the sand control methods used. Implementation of an effective sand control program insured the successful development of this field. Gravel packed wells had substantially lower production decline rates than the initial completions without gravel packs. Control of sand production also has been demonstrated by the lack of sand problems during the 4-1/2 yr since the sand control program was initiated. During this time there have been no failures of submersible pumps that were associated with sand production. The successful sand control program was achieved by a well coordinated and cooperative effort of drilling, reservoir engineering, production research, and service company personnel.

  17. Explaining the surprisingly poor correlation between turbulent surface wind and aeolian sand flux

    NASA Astrophysics Data System (ADS)

    Martin, R. L.; Barchyn, T. E.; Hugenholtz, C.; Jerolmack, D. J.; Kok, J. F.

    2012-12-01

    Existing models of aeolian sand transport, derived theoretically and from wind-tunnel experiments, often disagree substantially with field observations. Despite advancements in anemometry and sediment flux detection technologies, even very high-resolution observations of aeolian sand transport show only weak correlation with concurrent surface wind speeds and model predictions. Unlike in experiments and numerical models, winds in natural environments exhibit turbulent fluctuations over a broad range of length scales extending from individual grains to the top of the atmospheric boundary layer and over a similarly large range of time scales. Here, we present simultaneous high-resolution (10 Hz) measurements of surface wind and saltation sand transport over a ~5 m tall barchan dune (median grain diameter = 0.35 mm) collected at White Sands Dune Field, New Mexico, USA. Studying aeolian transport in the field offered a natural experiment for understanding how the rate of aeolian saltation responds to turbulent changes in wind and frequent crossings of the threshold for particle motion. In agreement with past observations, our data indicate that: (1) saltation flux lags wind fluctuations by about 1 second, (2) the threshold for initiation of particle motion ("entrainment") exceeds the threshold for cessation ("distrainment") by about 20%, (3) concurrent instantaneous wind and sediment flux measurements are poorly correlated. Based on our data, we show how lagged transport and threshold hysteresis are related to inertia in the transport system arising from ballistic particle trajectories and non-instantaneous momentum transfers among grains and wind. We argue that this nonlinear and lagged response of saltation to turbulent wind fluctuations accounts for the poor correlation between wind and transport as well as the poor performance of existing saltation models.

  18. Development history of deep water Plio-Pleistocene sands in the East Breaks 165 field, Gulf of Mexico

    SciTech Connect

    Bernaski, G.; Guderjahn, C.G. (BP Exploration, Houston, TX (United States))

    1991-03-01

    The stratigraphic complexity of the Plio-Pleistocene reservoir sands in the East Breaks 165 field (offshore Texas) is readily demonstrated after the completion of exploration and development involved: (1) prediction of turbidite sand facies distributions and thickness, and (2) identification of fault offsets in the high variable reservoir sands. The well control and a 3D seismic data set provide the basis for reservoir description and a deepwater sand depositional model in the East Breaks 165 area. Four main productive sand intervals are present in the Plio-Pleistocene section. All are characterized by rapid lateral thickness and facies and fining-upward channel levee/overbank facies. The channel systems developed within an intraslope basin. The main reservoir structure is a highly faulted anticline located downthrown to northeast-trending extensional faults with up to 2,500 feet of displacement. The faulting is result of structural collapse owing to salt withdrawal from a salt-cored anticlinal ridge. Numerous small-scale faults that juxtapose permeable and impermeable units have added further complexity to the field development. The refined turbidite channel and channel levee/overbank model has been important in delineating future recompletion and development targets in the East Breaks 165 field. This model should also prove to be a useful analog for future Gulf of Mexico deepwater exploration and development programs.

  19. Characterization and pattern recognition of oil–sand naphthenic acids using comprehensive two-dimensional gas chromatography\\/time-of-flight mass spectrometry

    Microsoft Academic Search

    Chunyan Hao; John V. Headley; Kerry M. Peru; Richard Frank; Paul Yang; Keith R. Solomon

    2005-01-01

    Oil–sand naphthenic acids (NAs) are organic wastes produced during the oil–sand digestion and extraction processes and are very difficult to separate and analyze as individual components due to their complex compositions. A comprehensive two-dimensional gas chromatography\\/time of flight mass spectrometry (GC×GC\\/TOF–MS) system was applied for the characterization of two commercial mixtures of naphthenic acids (Fluka and Acros) and a naphthenic

  20. Influence of hydraulic conductivity on communities of microorganisms and invertebrates in porous media: a case study in drinking water slow sand filters

    Microsoft Academic Search

    Laurie Mauclaire; Andreas Schürmann; Florian Mermillod-Blondin

    2006-01-01

    .  The impact of reduced hydraulic conductivity on the abundance and diversity of microorganisms and invertebrates was examined\\u000a in an artificial ecosystem consisting of a slow sand-filter. Sand-filters processed pre-treated lake water under high flow\\u000a rates and acted as small ecosystems inhabited by a complex community. The first trophic level consisting of microorganisms\\u000a serves as a food source for a dense

  1. Why Count Types of White Blood Cells?

    NSDL National Science Digital Library

    Ethel D. Stanley (Beloit College; Biology)

    2006-05-20

    How can we make use of complex cellular level responses in the human body to microbial infections and other disorders? Why is it important to differentiate between white blood cells in a blood sample and keep a record of their numbers? Improve skills at cell identification and explore these questions with the program Cell Differentials. * identify lymphocytes in a clinical laboratory simulation of blood cell counts

  2. Mesophilic Actinomycetes in the natural and reconstructed sand dune vegetation zones of Fraser Island, Australia.

    PubMed

    Kurtböke, D I; Neller, R J; Bellgard, S E

    2007-08-01

    The natural coastal habitat of Fraser Island located in the State of Queensland, Australia, has been disturbed in the past for mining of the mineral sand ilmenite. Currently, there is no information available on whether these past mining disturbances have affected the distribution, diversity, and survival of beneficial soil microorganisms in the sand dunes of the island. This in turn could deleteriously affect the success of the natural regeneration, plant growth, and establishment on the sand dunes. To support ongoing restoration efforts at sites like these mesophilic actinomycetes were isolated using conventional techniques, with particular emphasis on the taxa previously reported to produce plant-growth-promoting substances and providing support to mycorrhizal fungi, were studied at disturbed sites and compared with natural sites. In the natural sites, foredunes contained higher densities of micromonosporae replaced by increasing numbers of streptomycete species in the successional dune and finally leading to complex actinomycete communities in the mature hind dunes. Whereas in the disturbed zones affected by previous mining activities, which are currently being rehabilitated, no culturable actinomycete communities were detected. These findings suggest that the paucity of beneficial microflora in the rehabilitated sand dunes may be limiting the successful colonization by pioneer plant species. Failure to establish a cover of plant species would result in the mature hind dune plants being exposed to harsh salt and climatic conditions. This could exacerbate the incidence of wind erosion, resulting in the destabilization of well-defined and vegetated successional dunal zones. PMID:17578635

  3. Urn model of separation of sand.

    PubMed

    Lipowski, Adam; Droz, Michel

    2002-03-01

    We introduce an urn model that describes spatial separation of sand. In this dynamical model, in a certain range of parameters spontaneous symmetry breaking takes place and equipartitioning of sand into two compartments is broken. The steady-state equation for an order parameter, a critical line, and the tricritical point on the phase diagram are found exactly. The master equation and the first-passage problem for the model are solved numerically and the results are used to locate first-order transitions. Exponential divergence of a certain characteristic time shows that the model can also exhibit very strong metastability. In certain cases characteristic time diverges as N(z), where N is the number of balls and z=1 / 2 (critical line), 2 / 3 (tricritical point), or 1 / 3 (limits of stability). PMID:11909046

  4. Three dimensional fabric evolution of sheared sand

    SciTech Connect

    Hasan, Alsidqi; Alshibli, Khalid (UWA)

    2012-10-24

    Granular particles undergo translation and rolling when they are sheared. This paper presents a three-dimensional (3D) experimental assessment of fabric evolution of sheared sand at the particle level. F-75 Ottawa sand specimen was tested under an axisymmetric triaxial loading condition. It measured 9.5 mm in diameter and 20 mm in height. The quantitative evaluation was conducted by analyzing 3D high-resolution x-ray synchrotron micro-tomography images of the specimen at eight axial strain levels. The analyses included visualization of particle translation and rotation, and quantification of fabric orientation as shearing continued. Representative individual particles were successfully tracked and visualized to assess the mode of interaction between them. This paper discusses fabric evolution and compares the evolution of particles within and outside the shear band as shearing continues. Changes in particle orientation distributions are presented using fabric histograms and fabric tensor.

  5. Magnetic White Dwarfs

    NASA Astrophysics Data System (ADS)

    Ferrario, Lilia; de Martino, Domitilla; Gänsicke, Boris T.

    2015-05-01

    In this paper we review the current status of research on the observational and theoretical characteristics of isolated and binary magnetic white dwarfs (MWDs). Magnetic fields of isolated MWDs are observed to lie in the range 103-109 G. While the upper limit cutoff near 109 G appears to be real, the lower limit is more difficult to investigate. The incidence of magnetism below a few 103 G still needs to be established by sensitive spectropolarimetric surveys-conducted on 8 m class telescopes. Highly magnetic WDs tend to exhibit a complex and non-dipolar field structure with some objects showing the presence of higher order multipoles. There is no evidence that fields of highly magnetic WDs decay over time, which is consistent with the estimated Ohmic decay times scales of ˜1011 yrs. The slow rotation periods (˜100 yrs) inferred for a large number of isolated MWDs in comparison to those of non-magnetic WDs (a few days) suggest that strong magnetic fields augment the braking of the stellar core. MWDs, as a class, also appear to be more massive (0.784±0.047 M?) than their weakly or non-magnetic counterparts (0.663±0.136 M?). MWDs are also found in binary systems where they accrete matter from a low-mass donor star. These binaries, called magnetic Cataclysmic Variables (MCVs), comprise about 20-25 % of all known CVs. Zeeman and cyclotron spectroscopy of MCVs have revealed the presence of fields in the range ˜7-230 MG. Complex field geometries have been inferred in the high field MCVs (the polars) whilst magnetic field strength and structure in the lower field group (intermediate polars, IPs) are much harder to establish. The MCVs exhibit an orbital period distribution which is similar to that of non magnetic CVs. Polars dominate the distribution at orbital periods ?4 h and IPs at longer periods. It has been argued that IPs above the 2-3 hr CV period gap with magnetic moments ? 5×1033 G cm3 may eventually evolve into polars. It is vital to enlarge the still incomplete sample of MCVs to understand not only their accretion processes but also their evolution. The origin of fields in MWDs is still being debated. While the fossil field hypothesis remains an attractive possibility, field generation within the common envelope of a binary system has been gaining momentum, since it would explain the absence of MWDs paired with non-degenerate companions and also the lack of relatively wide pre-MCVs.

  6. Comparison of SAND-II and FERRET

    SciTech Connect

    Wootan, D.W.; Schmittroth, F.

    1981-01-01

    A comparison was made of the advantages and disadvantages of two codes, SAND-II and FERRET, for determining the neutron flux spectrum and uncertainty from experimental dosimeter measurements as anticipated in the FFTF Reactor Characterization Program. This comparison involved an examination of the methodology and the operational performance of each code. The merits of each code were identified with respect to theoretical basis, directness of method, solution uniqueness, subjective influences, and sensitivity to various input parameters.

  7. Liquefaction characteristics of a fine sand

    E-print Network

    Brandon, Donald Timothy

    1974-01-01

    during monotonic loading. During cyclic loading, from the limited results obtained, it appears that partially saturated samples are more susceptible to unlind. ted flow than saturated samples. iv ACKNOWLEDGMENTS The author gratefully acknowledges... on Soils CHAPTER III ? MATERIAL PROPERTIES AND TEST APPARATUS. Potter's Flint Ottawa Sand Test Apparatus 16 16 18 20 CHAPTER IV - TRIAXIAL TEST PROCEDURE. Sample Preparation Compaction Procedure Saturation and Consolidation Desaturation Axial...

  8. Solvent extraction of Southern US tar sands

    SciTech Connect

    Penney, W.R.

    1990-01-01

    The Department of Chemical Engineering at the University of Arkansas, in association with Diversified Petroleum Recovery, Inc. (DPR) of Little Rock, Arkansas, has been developing a solvent extraction process for the recovery of bitumen from tar sands for the past five years. The unique feature of the process is that the bitumen is recovered from the solvent by contacting with a co-solvent, which causes the bitumen to precipitate. The overall purpose of this project is to study both the technical and economic feasibility of applying this technology for recovery of bitumen from tar sands by (1) investigating the socioeconmic factors which affect (a) plant siting and (b) the market value of recovered bitumen; (2) operating a process demonstration unit at the rate of 1 lb/hr recovered bitumen while producing clean sand and recyclable solvents; and (3) determine the economic conditions which will make a bitumen recovery project economical. DPR has analyzed the historical trends of domestic production, consumption, discoveries and reserves of crude oil. They have started an investigation of the volatility in the price of crude oil and of gasoline prices and of the differential between gasoline and crude oil. DPR continues to analyze the geographical movement and demand for asphalt products. Utah does not appear economically attractive as a site for a bitumen from tar sands asphalt plant. Oklahoma sites are now being studied. This report also contains the quarterly progress report from a University of Nevada study to determine bitumen composition, oxygen uptake rates, and viscosities of Alabama and Utah bitumens. Both reports have been indexed separately for inclusion on the data base.

  9. Western Gas Sands Project status report

    Microsoft Academic Search

    1978-01-01

    The status of government sponsored projects undertaken to increase gas production from low-permeability gas sands of the western United States during August 1978 is summarized. Background information is given in the September 1977 Status Report, NVO\\/0655-100. One of the largest massive Hydraulic Fracture (MHF) treatment to date was performed on Gas Producing Enterprises Well No. CIGE 2-29. C.H. Atkinson, Western

  10. Flocculation settling characteristics of mud: sand mixtures

    Microsoft Academic Search

    Andrew J. Manning; John V. Baugh; Jeremy R. Spearman; Richard J. S. Whitehouse

    2010-01-01

    When natural muds become mixed with sandy sediments in estuaries, it has a direct effect on the flocculation process and resultant\\u000a sediment transport regime. Much research has been completed on the erosion and consolidation of mud\\/sand mixtures, but very\\u000a little is known quantitatively about how mixed sediments interact whilst in suspension, particularly in terms of flocculation.\\u000a This paper presents the

  11. Gravity and density dependences of sand avalanches

    Microsoft Academic Search

    P. Evesque; D. Fargeix; P. Habib; M. P. Luong; P. Porion

    1992-01-01

    We demonstrate using centrifuge experiment (10 1000 m\\/s^2) on sand avalanches that: i) grain cohesion is negligible, ii) the avalanche size and the maximum angle of repose depend on the initial pile-density, iii) an internal friction angle may be defined and corresponds to that measured with triaxial cell as assumed in soil mechanics. These data are coherent with a dilatancy

  12. Guide to preparing SAND reports. Revised

    SciTech Connect

    Locke, T.K. [ed.

    1996-04-01

    This guide contains basic information needed to produce a SAND report. Its guidelines reflect DOE regulation and Sandia policy. The guide includes basic writing instructions in an annotated sample report; guidance for organization, format, and layout of reports produced by line organizations; and information about conference papers, journal articles, and brochures. The appendixes contain sections on Sandia`s preferred usage, equations, references, copyrights and permissions, and publishing terms.

  13. Sand Martin Riparia riparia ? male or female?

    Microsoft Academic Search

    E. Cowley

    1999-01-01

    8,037 examinations were made of brood patches of Sand Martins from 1971 to 1992 in north Nottinghamshire and given one of 12 different descriptions. The 1,997 birds which were examined more than once (5,443 times in total) and identified as 1,061 females and 936 males from the types of patch\\/es they had carried were then used to test the accuracy

  14. White light velocity interferometer

    DOEpatents

    Erskine, David J. (Oakland, CA)

    1997-01-01

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s.

  15. White light velocity interferometer

    DOEpatents

    Erskine, David J. (Oakland, CA)

    1999-01-01

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s.

  16. White light velocity interferometer

    DOEpatents

    Erskine, D.J.

    1997-06-24

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

  17. New production techniques for alberta oil sands.

    PubMed

    Carrigy, M A

    1986-12-19

    Low world oil prices represent a serious threat to expanded commercial development of the Canadian oil sands in the near term, as they do to all of the higher cost alternatives to crude oil such as oil shales and coal liquefaction. Nonetheless, research and field testing of new technology for production of oil from oil sands are being pursued by industry and government in Alberta. New production technology is being developed in Canada to produce synthetic oil from the vast resources of bitumen trapped in the oil sands and bituminous carbonates of northern Alberta. This technology includes improved methods of mining, extraction, and upgrading of bitumen from near-surface deposits as well as new drilling and production techniques for thermal production of bitumen from the more deeply buried reservoirs. Of particular interest are the cluster drilling methods designed to reduce surface disturbance and the techniques for horizontal drilling of wells from underground tunnels to increase the contact of injection fluids with the reservoir. PMID:17816505

  18. Recovery of hydrocarbons from tar sands

    SciTech Connect

    Dente, M.; Antonelli, L.; Gallazzi, C.

    1984-07-10

    The process for the substantially total recovery of hydrocarbons from oil sands comprises: Preconditioning of the sands with diluent, possibly water (which may also be recycled from the process) and, preferably, with recycle extract; digestion of the homogeneous pulp, with (process) water; a first separation of the water-sand suspension from the hydrocarbon phase and from the digestion water; simultaneous washing and mixing of the solids separated from the bulk of the hydrocarbon phase in thick phase with overflowing water; a possible second separation of the dense solid mass from the excess liquid phase, the intermediate aqueous layer from the first separation (middlings) undergoing decantation and thickening and the solids so thickened undergoing centrifugation and stripping for the recovery of the limited proportions of diluent entrained with it. The equipment for this process consists of a preconditioner, a digestor, a first separator, a thick phase mixer, a possible second separator, a decanter-thickener, a centrifuge and a stripper, besides the possible apparatus for treating the diluted bitumen.

  19. Continental scale fluvial sediment recycling as expressed by a constant cosmogenic nuclide ratio in sand supplied from the Nile River over the last 2.5 Ma

    NASA Astrophysics Data System (ADS)

    Matmon, Ari; Davis, Michael; Rood, Dylan; Avnaim-katav, Simona

    2013-04-01

    Quartz in the eastern Mediterranean coastal plain is supplied through an extended transport system, which includes the Nile River, east Mediterranean longshore currents, and inland (Aeolian) sand transport. During this long and complex transport system, quartz grains are dosed with cosmogenic nuclides. While the concentrations of 26Al and 10Be, and their ratio, in modern sand deposited along the coast of the eastern Mediterranean reflect the combined effect of sand exposure and burial during transport, the concentrations of these nuclides in ancient buried sand are the result of decay of such an initial dosing. Samples of modern exposed sand (n=3) collected from the coastal plain of Israel yield an average 26Al/10Be ratio of 4.8±0.2, significantly lower than the expected ratio of 6.8 for exposed quartz grains at the surface. This ratio is equivalent to an apparent burial period of ~600 ka. A ratio of 4.5±0.3 was measured in a Pleistocene last glacial sand sample. This ratio is similar, within 1? to the average ratio of the modern sand indicating similar exposure-burial histories during transport in spite of the difference in climatic conditions. The results imply a steady, pre-burial cosmogenic nuclide ratio related to the Nile River's ability, through storage and recycling, to buffer the effects of climatic and tectonic perturbations on cosmogenic nuclide concentrations in the transported quartz. All ancient and buried sand samples (n=9) fall on a decay path which originates from concentrations and ratio of 26Al and 10Be in modern sand suggesting steady pre-burial concentrations of cosmogenic nuclides in quartz sand over the past 2.5 Ma.

  20. Tracheids in white spruce seedling's long lateral roots in response to nitrogen availability

    Microsoft Academic Search

    M. J. Krasowski; J. N. Owens

    1999-01-01

    This study examined how the availability of inorganic nitrogen (N) modified the anatomical characteristics of white spruce\\u000a (Picea glauca (Moench) Voss) roots related to their hydraulic properties. Seedlings were grown for one growing season in 4\\u000a L capacity pots filled with sand under one of three N levels: low (10 ppm), medium (50 ppm) and high (125 ppm). First order

  1. Policy Analysis of the Canadian Oil Sands Experience

    SciTech Connect

    None, None

    2013-09-01

    For those who support U.S. oil sands development, the Canadian oil sands industry is often identified as a model the U.S. might emulate, yielding financial and energy security benefits. For opponents of domestic oil sands development, the Canadian oil sands experience illustrates the risks that opponents of development believe should deter domestic policymakers from incenting U.S. oil sands development. This report does not seek to evaluate the particular underpinnings of either side of this policy argument, but rather attempts to delve into the question of whether the Canadian experience has relevance as a foundational model for U.S. oil sands development. More specifically, this report seeks to assess whether and how the Canadian oil sands experience might be predictive or instructive in the context of fashioning a framework for a U.S. oil sands industry. In evaluating the implications of these underpinnings for a prospective U.S. oil sands industry, this report concentrates on prospective development of the oil sands deposits found in Utah.

  2. Exploring Whiteness: A Study of Self Labels for White Americans.

    ERIC Educational Resources Information Center

    Martin, Judith N.; Krizek, Robert L.; Nakayama, Thomas K.; Bradford, Lisa

    1996-01-01

    Examines the preferences and meanings of labels for White Americans as discursively defined expressions of identity, after preliminary revelations of resistance by Whites to self-labeling was seen. Surveys 371 White undergraduate students, rating seven labels regarding preference and discussing feelings about self-labeling. Reveals that the most…

  3. Evaluation of ERTS-1 imagery in mapping and managing soil and range resources in the Sand Hills Region of Nebraska

    NASA Technical Reports Server (NTRS)

    Seevers, P. M.; Drew, J. V.

    1973-01-01

    Interpretations of high altitude photography of test sites in the Sandhills of Nebraska permitted identification of subirrigated range sites as well as complexes of choppy sands and sands range sites, units composing approximately 85% of the Sandhills rangeland. These range sites form the basic units necessary for the interpretation of range condition classes used in grazing management. Analysis of ERTS-1 imagery acquired during August, September and October, 1972 indicated potential for the identification of gross differences in forage density within given range sites identified on early season aerial photography.

  4. Public Address SUSAN WHITING

    E-print Network

    Collins, Gary S.

    and Wealth in Rural China: The Political Economy of Institutional Change, was published by Cambridgepresent Public Address SUSAN WHITING "Is China Governed by Law?" Monday, October 29, 4:00 pm, CUE and comparative politics, with an emphasis on the political economy of development. Her first book, Power

  5. White Sea - Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    At bottom center of this true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from April 13, 2001, the White Sea in western Russia is becoming free of ice in its southern extent. Meanwhile, the blue-green waters along the coast of the peninsula jutting out into the Barents Sea to the northeast could be due to a phytoplankton bloom.

  6. PREFACE: WMO/GEO Expert Meeting On An International Sand And Dust Storm Warning System

    NASA Astrophysics Data System (ADS)

    Pérez, C.; Baldasano, J. M.

    2009-03-01

    This volume of IOP Conference Series: Earth and Environmental Science presents a selection of papers that were given at the WMO/GEO Expert Meeting on an International Sand and Dust Storm Warning System hosted by the Barcelona Supercomputing Center - Centro Nacional de Supercomputación in Barcelona (Spain) on 7-9 November 2007 (http://www.bsc.es/wmo). A sand and dust storm (SDS) is a meteorological phenomenon common in arid and semi-arid regions and arises when a gust front passes or when the wind force exceeds the threshold value where loose sand and dust are removed from the dry surface. After aeolian uptake, SDS reduce visibility to a few meters in and near source regions, and dust plumes are transported over distances as long as thousands of kilometres. Aeolian dust is unique among aerosol phenomena: (1) with the possible exception of sea-salt aerosol, it is globally the most abundant of all aerosol species, (2) it appears as the dominating component of atmospheric aerosol over large areas of the Earth, (3) it represents a serious hazard for life, health, property, environment and economy (occasionally reaching the grade of disaster or catastrophic event) and (4) its influence, impacts, complex interactions and feedbacks within the Earth System span a wide range of spatial and temporal scales. From a political and societal point of view, the concern for SDS and the need for international cooperation were reflected after a survey conducted in 2005 by the World Meteorological Organization (WMO) in which more than forty WMO Member countries expressed their interest for creating or improving capacities for SDS warning advisory and assessment. In this context, recent major advances in research - including, for example, the development and implementation of advanced observing systems, the theoretical understanding of the mechanisms responsible for sand and dust storm generation and the development of global and regional dust models - represent the basis for developing applications focusing on societal benefit and risk reduction. However, at present there are interdisciplinary research challenges to overwhelm current uncertainties in order to reach full potential. Furthermore, the community of practice for SDS observations, forecasts and analyses is mainly scientifically based and rather disconnected from potential users. This requires the development of interfaces with operational communities at international and national levels, strongly focusing on the needs of people and factors at risk. The WMO has taken the lead with international partners to develop and implement a Sand and Dust Storm Warning Advisory and Assessment System (SDS-WAS). The history of the WMO SDS-WAS development is as follows. On 12-14 September 2004, an International Symposium on Sand and Dust Storms was held in Beijing at the China Meteorological Agency followed by a WMO Experts Workshop on Sand and Dust Storms. The recommendations of that workshop led to a proposal to create a WMO Sand and Dust Storm Project coordinated jointly with the Global Atmosphere Watch (GAW). This was approved by the steering body of the World Weather Research Programme (WWRP) in 2005. Responding to a WMO survey conducted in 2005, more than forty WMO Member countries expressed interest in participating in activities to improve capacities for more reliable sand and dust storm monitoring, forecasting and assessment. On 31 October to 1 November 2006 in Shanghai, the steering committee of the Sand and Dust Storm Project proposed the development and implementation of a Sand and Dust Storm Warning, Advisory and Assessment System (SDS-WAS). The WMO Secretariat in Geneva formed an ad-hoc Internal Group on SDS-WAS consisting of scientific officers representing WMO research, observations, operational prediction, service delivery and applications programmes such as aviation and agriculture. In May 2007, the 14th WMO Congress endorsed the launching of the SDS-WAS. It also welcomed the strong support of Spain to host a regional centre for the European/African/Middle East node of SDS-WAS a

  7. The White Sea, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Editor's Note: The caption below, published on May 10, 2001, is incorrect. According to Masha Vorontsova, director of the International Fund for Animal Welfare in Moscow, the situation with the seal pups in the White Sea is normal. There is no disaster and there never was. For more details, refer to the article entitled 'No Danger' on the New Scientist home page. The Earth Observatory regrets the earlier errant report. Original Caption According to the Russian Polar Research Institute for Fisheries and Oceanography, between 250,000 and 300,000 Greenland seal pups face death by starvation over the next two months due to a cruel trick by mother nature. The seals, most of them less than two months old, are trapped on ice sheets that remain locked in the White Sea, located near Archangel in Northern Russia. Typically, during the spring thaw the ice sheets break up and flow with the currents northward into the Barents Sea, the seals' spring feeding grounds. The seal pups hitch a ride on the ice floes, living on their own individual stores of fat until they arrive in the Barents Sea. Their mothers departed for the Barents Sea weeks ago. In a normal year, the seal pups' trip from the White Sea out to the Barents takes about six weeks and the seals have adapted to rely upon this mechanism of mother nature. During their yearly migration, the mother seals usually stay with their pups and feed them until their pelts turn from white to grey--a sign that the pups are mature enough to swim and feed themselves. Unfortunately, this year unusually strong northerly winds created a bottleneck of ice near the mouth of the white sea, thus blocking the flow of ice and trapping the pups. These true-color images of the White Sea were acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. This image, taken May 2, 2000 that there is usually much less ice in the White Sea this time of year as most of it is typically en route to the Barents Sea.

  8. An airborne assessment of atmospheric particulate emissions from the processing of Athabasca oil sands

    NASA Astrophysics Data System (ADS)

    Howell, S. G.; Clarke, A. D.; Freitag, S.; McNaughton, C. S.; Kapustin, V.; Brekovskikh, V.; Jimenez, J.-L.; Cubison, M. J.

    2014-05-01

    During the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) campaign, two NASA research aircraft, a DC-8 and a P-3B, were outfitted with extensive trace gas (the DC-8) and aerosol (both aircraft) instrumentation. Each aircraft spent about a half hour sampling air around the oil sands mining and upgrading facilities near Ft. McMurray, Alberta, Canada. The DC-8 circled the area, while the P-3B flew directly over the upgrading plants, sampling close to the exhaust stacks, then headed downwind to monitor the aerosol as it aged. At short range, the plume from the oil sands is a complex mosaic of freshly nucleated ultrafine particles from a SO2- and NO2-rich plume, soot and possibly fly ash from industrial processes, and dust from dirt roads and mining operations. Shortly downwind, organic aerosol appears in quantities that rival SO4, either as volatile organic vapors condense or as they react with the H2SO4. The DC-8 pattern allowed us to integrate total flux from the oil sands facilities within about a factor of 2 uncertainty that spanned values consistent with 2008 estimates from reported SO2 and NO2 emissions, though there is no reason to expect one flyby to represent average conditions. In contrast, CO fluxes exceeded reported regional emissions, due either to variability in production or sources missing from the emissions inventory. The conversion rate of SO2 to aerosol SO4 of ~6% per hour is consistent with earlier reports, though OH concentrations are insufficient to accomplish this. Other oxidation pathways must be active. Altogether, organic aerosol and black carbon emissions from the oil sands operations are small compared with annual forest fire emissions in Canada. The oil sands do contribute significant sulfate and exceed fire production of SO2 by an order of magnitude.

  9. One-step cell lysis suitable for quantitative bacteria detection in inhibitor-laden sands

    NASA Astrophysics Data System (ADS)

    Lim, Hyun Jeong; Choi, Jung-Hyun; Son, Ahjeong

    2015-04-01

    Complexity and heterogeneity of soils often hinder effective DNA extraction from the soil matrix. In particular, conventional DNA extraction techniques require extensive purification which makes DNA extraction time-consuming and labor-intensive. Other drawbacks include lower recovery yield, degradation, and damage of DNA, which are also caused by intensive purifications during DNA extraction. Therefore a rapid and simple and yet effective DNA pretreatment method is preferred for environmental monitoring and screening. This study has evaluated the feasibility of simple physical pretreatment for effective cell lysis of bacteria in sands. Bead beating method was selected as an effective physical cell lysis method in this study. We examined the capability of this physical lysis for Pseudomonas putida seeded sands without additional chemical purification steps. The lysate from the method was analysed by the quantitative polymerase chain reaction (qPCR) assay and subsequently compared to that by commercial DNA extraction kit. The best lysis condition (treatment with 0.1 mm glass beads at 3000 rpm for 3 minutes) was selected. The qPCR results of bead beating treated samples showed the better performance than that of conventional DNA extraction kit. Moreover, the qPCR assay was performed to the sands laden with qPCR inhibitors (humic acids, clay, and magnesium), which generally present in environmental samples. Further experiments with the sands containing less than 10 ?g/g of humic acids and 70% of clay showed successful quantification results of qPCR assay. In conclusion, the bead beating method is useful for simplified DNA extraction prior to qPCR analysis for sand samples of particular composition. It is expected that this approach will be beneficial for environmental in-situ analysis or immediate pre-screening. It also provides the groundwork for future studies with real soil samples that have various physico-chemical properties.

  10. Storms, shoreface morphodynamics, sand supply, and the accretion and erosion of coastal dune barriers in the southern North Sea

    NASA Astrophysics Data System (ADS)

    Anthony, Edward J.

    2013-10-01

    The coast of the southern North Sea is bound by dune barriers that have developed adjacent to a shallow storm- and tide-dominated shoreface comprising numerous shore-parallel to sub-shore-parallel tidal sand banks. The banks evolve under the joint control of tide-, wave- and wind-induced shore-parallel currents, which tend to ‘stretch' them, eventually leading to bank division, and to shoaling and breaking storm waves, which tend to drive them ashore. The banks, thus, modulate the delivery of storm wave energy to the coast, redirect currents alongshore and are the sand sources for the accretion of coastal dunes. Foredune accretion occurs where major sand banks have migrated shoreward over the last centuries to be finally driven ashore and weld under the impact of storm waves. Morphological changes in the bank field can impact on shoreline stability through dissipation or enhanced shoreward transmission of storm wave energy and effects on radiation stress, particularly when waves are breaking over the banks. Where banks are close to the shore, mitigation of offshore sediment transport, especially during storms, can occur because of gradients in radiation stress generated by the complex 3D bank structure. These macro-scale mechanisms involve embedded meso-scale interactions that revolve around the mobility of sand waves, mobility of beach bars and troughs and foredune mobility, and micro-scale processes of bedform mobility in the subaqueous and intertidal domains, and of swash and aeolian beach-dune sand transport. These embedded interactions and the morphodynamic feedback loops illustrate the importance of synchroneity of sand transport from shoreface to dune on this coast. Large stretches of the foredunes show either signs of stability, or mild but chronic erosion. Furthermore, a demonstrated lack of a clear relationship occurs between storminess and coastal response over the second half of the 20th century. The present situation may be indicative of conditions of rather limited sand supply from offshore, notwithstanding the abundance of sand on the nearby shallow shoreface, except in areas where a nearshore storm-driven tidal sand bank has become shore-attached. Apart from the important influence of shoreface sand banks and of wave-bank interactions, foredune accretion and erosion also depend on various context controls that include individual storm characteristics, wind speed and incidence relative to the shore, tidal stage during storms, and direct human intervention on the shore through foredune and beach management. The bewildering variability inherent in these intricately related parameters may also explain the poor relationship between storminess and barrier shoreline change and will still continue to render unpredictable the response of shores to individual storms.

  11. Asteroseismology of White Dwarf Stars

    NASA Technical Reports Server (NTRS)

    Hansen, Carl J.

    1997-01-01

    The primary purpose of this investigation has been to study various aspects of multimode pulsations in variable white dwarfs. In particular, nonlinear interactions among pulsation modes in white dwarfs (and, to some extent, in other variable stars), analysis of recent observations where such interactions are important, and preliminary work on the effects of crystallization in cool white dwarfs are reported.

  12. Egg White Phantoms for HIFU

    SciTech Connect

    Divkovic, Gabriela; Jenne, Juergen W. [German Cancer Research Center Heidelberg, Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2005-03-28

    We used fresh egg white and polyacrylamide to create a transparent tissue mimicking phantom. Heating of phantoms by HIFU leads to egg white protein denaturation and creation of visible white lesions. We measured the acoustical and thermal properties and investigated the possibility to use such phantoms to study the lesion formation during the HIFU therapy.

  13. Environmental impact statement for Manned Spacecraft Center and White Sands Test Facility

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This environment has not only attracted people and increased payrolls, but has also created a broader base for the local economy. The activity of the center was a catalyst to private enterprise and has led to sizeable residential and commercial developments. Adequate treatment of domestic and industrial waste water was maintained. A feasibility study is now being conducted to establish a plan for a coordinated, centerwide plan for advanced treatment of domestic and industrial waste water.

  14. Limited energy study Geodss Facility, White Sands Missile Range, New Mexico. Final report

    SciTech Connect

    NONE

    1995-11-01

    This study was performed and this report prepared under Contract No. DACA01-94-D-0033, Delivery Order No. 8. The delivery order was issued by U.S. Army Engineer District, Mobile, to E M C Engineers, Inc. on 8 May 1995. The purpose of this study is to identify and evaluate Energy Conservation Opportunities (ECOs), to determine their energy savings potential and economic feasibility, and to document results for possible future funding.

  15. Lowering the glycemic index of white bread using a white bean extract

    PubMed Central

    Udani, Jay K; Singh, Betsy B; Barrett, Marilyn L; Preuss, Harry G

    2009-01-01

    Background Phase 2® is a dietary supplement derived from the common white kidney bean (Phaseolus vulgaris). Phase 2 has been shown to inhibit alpha-amylase, the complex carbohydrate digesting enzyme, in vitro. The inhibition of alpha-amylase may result in the lowering of the effective Glycemic Index (GI) of certain foods. The objective of this study was to determine whether the addition of Phase 2 would lower the GI of a commercially available high glycemic food (white bread). Methods An open-label 6-arm crossover study was conducted with 13 randomized subjects. Standardized GI testing was performed on white bread with and without the addition of Phase 2 in capsule and powder form, each in dosages of 1500 mg, 2000 mg, and 3000 mg. Statistical analysis was performed by one-way ANOVA of all seven treatment groups using unadjusted multiple comparisons (t tests) to the white bread control. Results For the capsule formulation, the 1500 mg dose had no effect on the GI and the 2000 mg and 3000 mg capsule doses caused insignificant reductions in GI. For the powder, the 1500 mg and 2000 mg doses caused insignificant reductions in the GI, and the 3000 mg dose had a significant effect (-20.23 or 34.11%, p = 0.023) Conclusion Phase 2 white bean extract appears to be a novel and potentially effective method for reducing the GI of existing foods without modifying their ingredient profile. Trial Registration Trial Registration: ISRCTN50347345 PMID:19860922

  16. Cytotoxicity of yellow sand in lung epithelial cells

    Microsoft Academic Search

    Y. H. Kim; K. S. Kim; N. J. Kwak; K. H. Lee; S. A. Kweon; Y. Lim

    2003-01-01

    The present study was carried out to observe the cytotoxicity of yellow sand in comparison with silica and titanium dioxide\\u000a in a rat alveolar type II cell line (RLE-6TN). Yellow sand (China Loess) was obtained from the loess layer in the Gunsu Province\\u000a of China. The mean particle diameter of yellow sand was about 0003 ± 0.001 mm. Major elements

  17. Water Conservation and Management with Hydrophobic Encapsulation of Sand

    Microsoft Academic Search

    Mohammed A. Salem; Wasef Al-Zayadneh; Abdul Jaleel Cheruth

    2010-01-01

    Hydrophobic sand (HS) is ordinary beach sand coated with tiny particles of pure silica, which have been exposed to a special\\u000a chemical treatment vapors of a silicon compound called trimethylhydroxysilane (CH3)3SiOH. The additive creates a capillary breaking hydrophobic encapsulation of the sand making it resistant to salts, particularly\\u000a sodium chloride salts. This can be serving as a pure water repellent

  18. Final report on Thermally Modified Sand demonstration project

    SciTech Connect

    Not Available

    1994-09-23

    The use of salt and salt/sand mixtures on icy roadway surfaces has dramatically increased during the past 30 years. Despite extensive documentation on salt related damage to the roadway improvements, vehicles and the environment, road maintenance departments have continued to rely on this practice. Road maintenance departments in northern climate areas have long recognized the safety benefits for public mobility on icy roadways from the use of sand. As an abrasive material, the sand improves the surface traction that results in more drivable and less hazardous road conditions during the winter months. Stockpiles of pure sand stored during the winter months oftentimes freeze into large unworkable, monolithic piles. To maintain a free-flowing condition, it has been found to be necessary to add salt to the sand. The addition of salt in amounts ranging from 5 to 10 percent to that of sand, is usually sufficient to provide relatively free-flowing abrasive material that could be stored in stockpiles and applied to icy road surfaces with conventional sand spreading trucks. Another alternative for winter storage of pure sand to maintain a free-flowing condition is in humidity-controlled, heated buildings. As would be expected, this method has high capital and operating costs. and not cost effective for general highway maintenance use. The invention demonstrated herein is a method of thermally modifying pure sand that will remain in a free-flowing state throughout the winter season without the need for the salt additive. The thermally modified sand provides an abrasive material that when applied to icy roads does not cause environmental and corrosive damage as done by the application of sand with salt. By employing a very simple process of freezing screened sand particles by forced air convection under subfreezing conditions, the invention creates a product that has significant value in terms of economic and environmental benefits.

  19. Testing the Delaware sand filter's effectiveness for treating stormwater runoff

    SciTech Connect

    Leszczynska, D.; Dzurik, A.

    1998-07-01

    The use of the Delaware Sand Filter for treatment of ultra-urban stormwater is investigated for Florida applications. An experimental Delaware filter is designed in conjunction with a typical sand filter as part of a street improvement project in Tallahassee, Florida. The design allows for testing of different filter media in an attempt to determine the suitability of the Delaware Sand Filter in hot climates with numerous heavy rainfall episodes.

  20. Relationships Between Sand and Water Quality at Recreational Beaches

    PubMed Central

    Phillips, Matthew C.; Solo-Gabriele, Helena M.; Piggot, Alan M.; Klaus, James S.; Zhang, Yifan

    2011-01-01

    Enterococci are used to assess the risk of negative human health impacts from recreational waters. Studies have shown sustained populations of enterococci within sediments of beaches but comprehensive surveys of multiple tidal zones on beaches in a regional area and their relationship to beach management decisions are limited. We sampled three tidal zones on eight South Florida beaches in Miami-Dade and Broward counties and found that enterococci were ubiquitous within South Florida beach sands although their levels varied greatly both among the beaches and between the supratidal, intertidal and subtidal zones. The supratidal sands consistently had significantly higher (p<0.003) levels of enterococci (average 40 CFU/g dry sand) than the other two zones. Levels of enterococci within the subtidal sand correlated with the average level of enterococci in the water (CFU/100mL) for the season during which samples were collected (rs= 0.73). The average sand enterococci content over all the zones on each beach correlated with the average water enterococci levels of the year prior to sand samplings (rs=0.64) as well as the average water enterococci levels for the month after sand samplings (rs=0.54). Results indicate a connection between levels of enterococci in beach water and sands throughout South Florida’s beaches and suggest that the sands are one of the predominant reservoirs of enterococci impacting beach water quality. As a result, beaches with lower levels of enterococci in the sand had fewer exceedences relative to beaches with higher levels of sand enterococci. More research should focus on evaluating beach sand quality as a means to predict and regulate marine recreational water quality. PMID:22071324

  1. Sand erosion performance of CVD boron carbide coated tungsten carbide

    Microsoft Academic Search

    R. J. K Wood; D. W Wheeler; D. C Lejeau; B. G Mellor

    1999-01-01

    The erosion performance and the interaction between the micro-mechanisms of erosion and the microstructure of a chemical vapour deposited boron carbide coating are presented. Samples were tested using both water–sand slurry and air–sand jet impingements at 90° incidence. Tests used angular quartz sand with a mean diameter between 135 and 235 ?m and jet impingement velocities between 16 and 268

  2. The effect of fines upon the compaction characteristics of a well graded sand

    E-print Network

    Long, Robert Eugene

    1954-01-01

    and Compaction of the Material VII . Laboratory Compaction Characteristics of the Materials A +46 A. General Information . 46 B. The Well Graded Sand . 46 C. The Well Graded Sand Plus 2 Percent Sand Fines ~ ~ ~ ~ ~ ~ ~ ~ ~ . 47 D. The Well Graded Sand Plus 4..., 6 and 8 Percent Sand Fines F 4& E. The Well Graded Sand Plus 10 and 12 Percent Sand Fincsse 50 F. The Well Graded Sand Plus Silt and Clay Fires ~ 61 G. Sand, Silt and Clay Fines VIII. Influence of Fine Soil Additives on Compaction Charaoteristics...

  3. Mars Rover Curiosity Traverses of Sand Ripples

    NASA Astrophysics Data System (ADS)

    Stein, N.; Arvidson, R. E.; Zhou, F.; Heverly, M.; Maimone, M.; Hartman, F.; Bellutta, P.; Iagnemma, K.; Senatore, C.

    2014-12-01

    Martian sand ripples present a challenge for rover mobility, with drives over ripples often characterized by high wheel sinkage and slippage that can lead to incipient embedding. Since landing in Gale Crater, Curiosity has traversed multiple sand ripples, including the transverse aeolian ridge (TAR) straddling Dingo Gap on sols 533 and 535. On sol 672, Curiosity crossed backward over a series of sand ripples before ending its drive after high motor currents initiated visual odometry (VO) processing, which detected 77% slip, well in excess of the imposed 60% slip limit. At the end of the drive, the right front wheel was deeply embedded at the base of a ripple flank with >20 cm sinkage and the rear wheels were near a ripple crest. As Curiosity continues its approach to Mount Sharp it will have to cross multiple ripples, and thus it is important to understand Curiosity's performance on sol 672 and over similar ripples. To this end the sol 672 drive was simulated in ARTEMIS (Adams-Based Rover Terramechanics Interaction Simulator), a software tool consisting of realistic rover mechanical models, a wheel-terrain interaction module for deformable and non-deformable surfaces, and realistic terrain models. ARTEMIS results, Dumont Dunes tests performed in the Mojave Desert using the Scarecrow test rover, and single wheel tests performed at MIT indicate that the high slip encountered on sol 672 likely occurred due to a combination of rover attack angle, ripple geometry, and soil properties. When ripple wavelength approaches vehicle length, the rover can reach orientations in which the leading wheels carry minimal normal loads and the trailing wheels sink deeply, resulting in high slippage and insufficient thrust to propel the rover over ripples. Even on relatively benign (i.e. low tilt) terrains, local morphology can impose high sinkage, thus impeding rover motion. Work is underway to quantify Curiosity's drive performance over various ripple geometries to retrieve soil properties and to generate better driving practices across ripples.

  4. Borehole mining oil sands is compatible with environment

    SciTech Connect

    Not Available

    1981-05-01

    The US Bureau of Mines borehole mining system for oil sands is discussed. The object of the program was to develop an environmentally feasible method of mining shallow oil sands without removing the overburden. The method entails extracting oil sands through a single borehole by cutting into the sands around the borehole with a high pressure water jet, and pumping the resulting slurry to the surface. The system was successfully field tested at a site in the Midway-Sunset Oil Field near Taft, in Kern County, California. During the two-month period during and following mining operations, no significant ground surface subsidence of ground water pollution was detected. (JMT)

  5. Bioclogging and Biocementation in Construction of Water Pond in Sand

    NASA Astrophysics Data System (ADS)

    Chu, J.; Ivanov, V.; Stabnikov, V.; Li, B.

    2012-12-01

    Conventionally, compacted bentonite, geosynthetic clay liner or plastic liners are used to seal ponds, channels, and reservoirs in sand. Recently, a new approach to form a low permeability layer of several centimetres thick through the microbially induced calcium carbonate precipitation (MICP) process has been developed (Chu et al., 2012). This method has been adopted to build a laboratory scale water pond model in sand. Calcium solution for bioclogging and biocementation was supplied initially by spaying to form a layer of the clogged sand by precipitation in the pores and then by slow percolation from solution above sand surface, which formed a crust of calcite. This combination of bioclogging and biocementation formed a sand layer of 1 - 3 cm depth with low permeability. The permeability of sand after this treatment was reduced from the order of 10^-4 m/s to 10^-7 m/s when an average 2.1 kg of Ca per m^2 of sand surface was precipitated. The bending strengths of the walls and the base of the model pond were in the range of 90 to 256 kPa. The unconfined compressive strengths obtained from samples from the walls and the base were in the range of 215 to 932 kPa. The graded sand and uniform supply of calcium solution were used for the model pond construction but it was significant spatial three-dimensional heterogeneity of sand bioclogging and biocementation.

  6. Production and global transport of Titan's sand particles

    NASA Astrophysics Data System (ADS)

    Barnes, Jason W.; Lorenz, Ralph D.; Radebaugh, Jani; Hayes, Alexander G.; Arnold, Karl; Chandler, Clayton

    2015-06-01

    Previous authors have suggested that Titan's individual sand particles form by either sintering or by lithification and erosion. We suggest two new mechanisms for the production of Titan's organic sand particles that would occur within bodies of liquid: flocculation and evaporitic precipitation. Such production mechanisms would suggest discrete sand sources in dry lakebeds. We search for such sources, but find no convincing candidates with the present Cassini Visual and Infrared Mapping Spectrometer coverage. As a result we propose that Titan's equatorial dunes may represent a single, global sand sea with west-to-east transport providing sources and sinks for sand in each interconnected basin. The sand might then be transported around Xanadu by fast-moving Barchan dune chains and/or fluvial transport in transient riverbeds. A river at the Xanadu/Shangri-La border could explain the sharp edge of the sand sea there, much like the Kuiseb River stops the Namib Sand Sea in southwest Africa on Earth. Future missions could use the composition of Titan's sands to constrain the global hydrocarbon cycle.

  7. Brown DwarfBrown Dwarf Brown Dwarf White Dwarf White Dwarf White Dwarf

    E-print Network

    Bechtold, Jill

    Brown DwarfBrown Dwarf Brown Dwarf White Dwarf White Dwarf White Dwarf Yellow Dwarf Yellow Dwarf Yellow Dwarf Small dim barely detectable ball of gas. When brown dwarf stars form they do not have stars. Mass: StarPower Points: 2 Small dim barely detectable ball of gas. A brown dwarf

  8. Biogenic crust dynamics on sand dunes.

    PubMed

    Kinast, Shai; Meron, Ehud; Yizhaq, Hezi; Ashkenazy, Yosef

    2013-02-01

    Sand dunes are often covered by vegetation and biogenic crusts. Despite their significant role in dune stabilization, biogenic crusts have rarely been considered in model studies of dune dynamics. Using a simple model, we study the existence and stability ranges of different dune-cover states along gradients of rainfall and wind power. Two ranges of alternative stable states are identified: fixed crusted dunes and fixed vegetated dunes at low wind power; and fixed vegetated dunes and active dunes at high wind power. These results suggest a crossover between two different forms of desertification. PMID:23496449

  9. Application of Rule Based Expert System to Sand Control in Oil Fields

    Microsoft Academic Search

    Lai NanjunDong; Dong Wan; Wang Jie; Xiao Xia; Lai Junhui

    2012-01-01

    The rule based expert system model, structure and sand prevention method, sand control design, the evaluation of sand control in detail, and the expert system based on rule and sand control technology of combining rule based expert system, puts forward the comprehensive analysis and evaluation of sand control system, and successfully applied in some oil field.

  10. Effect of mould expansion on pattern allowances in sand casting of steel

    E-print Network

    Beckermann, Christoph

    Effect of mould expansion on pattern allowances in sand casting of steel F. Peters1 , R. Voigt2 , S. Z. Ou3 and C. Beckermann*3 For steel castings produced in sand moulds, the expansion of the sand a cylindrical casting to study this effect for different sands (silica and zircon) and different sand binder

  11. Tar sands of Alberta, Canada. [Review on reserves, history, properties and composition, technology, and commercial ventures

    Microsoft Academic Search

    1974-01-01

    The discussion is presented under the following section headings: occurrence and reserves; history of the Athabasca tar sands; properties and characteristics of Athabasca tar sands, including bulk properties, properties of tar sand minerals, bitumen properties, and properties of refined products; technology of the recovery of values from tar sands, including in-situ processes, mining, processing of mined tar sands for bitumen

  12. Tar sands of Alberta, Canada. [Review on reserves, history, properties and composition, technology, and commercial ventures

    Microsoft Academic Search

    1976-01-01

    The discussion is presented under the following section headings: occurrence and reserves; history of the Athabasca tar sands; properties and characteristics of Athabasca tar sands, including bulk properties, properties of tar sand minerals, bitumen properties, and properties of refined products; technology of the recovery of values from tar sands, including in-situ processes, mining, processing of mined tar sands for bitumen

  13. The flux profile of a blowing sand cloud: a wind tunnel investigation

    Microsoft Academic Search

    Zhibao Dong; Xiaoping Liu; Hongtao Wang; Aiguo Zhao; Xunming Wang

    2003-01-01

    The flux profile of a blowing sand cloud, or the variation of blown sand flux with height, is the reflection of blown sand particles that move in different trajectories, and also the basis for checking drifting sand. Here we report the wind tunnel results of systematic tests of the flux profiles of different sized sands at different free-stream wind velocities.

  14. Postmortem analysis of sand grain crushing from pile interface using X-ray tomography

    NASA Astrophysics Data System (ADS)

    Silva, I. Matías; Combe, Gaël; Foray, Pierre; Flin, Frédéric; Lesaffre, Bernard

    2013-06-01

    Pile foundations of offshore platforms, wind and water turbines are typically subjected to a variety of cyclic loading paths due to their complex environment. While many studies focus on global pile behaviour, the soil-pile interface is explored here by a micromechanical study of the soil layer in contact with the pile surface. This work is devoted to the analysis of frozen post-mortem silica sand samples recovered at the pile interface following installation and cyclic loading tests in a calibration chamber using x-ray tomography. An experimental procedure developed for three dimensional (3D) snow imaging was adapted for the recovery of the in-situ sand samples to preserve their structure during tomography scans. 3D images at a pixel size of 7 ?m were then obtained using a cryogenic cell. Results confirm the presence of a shear band at the pile surface as well as void ratios changes in the direction of the pile's radius.

  15. A study of morphology, provenance, and movement of desert sand seas in Africa, Asia, and Australia

    NASA Technical Reports Server (NTRS)

    Mckee, E. D. (principal investigator)

    1973-01-01

    The author has identified the following significant results. The most significant result to date is recongition that complexes are indeed visible on ERTS-1 images, and that the extent and nature of dune fields in many remote areas of the world can, for the first time, be observed almost simultaneously and directly compared. The primary scientific problem is to determine accurately the relationships among certain patterns, trends, and boundaries clearly revealed on ERTS-1 imagery to true surface configurations of desert landforms, and further, to relate the defined features to controlling factors such as wind direction and intensity, moisture in the air and on the ground and barriers to sand movement. It is hoped to produce, by photographic and cartographic extraction from ERTS-1 images, a set of thematic maps that will illustrate the relationships of optical appearance of various materials and effects of the color of various sand bodies upon ERTS-1 images.

  16. TRANSPORT OF MACROMOLECULES AND HUMATE COLLOIDS THROUGH A SAND AND A CLAY AMENDED SAND LABORATORY COLUMN

    EPA Science Inventory

    Laboratory experiments were conducted to determine if macromolecules or humate colloids would transport through sand columns and if they would exhibit any variations in their relative velocity based upon their molecular volumes and the pore size distribution of the column packing...

  17. CONE PENETRATION TESTING AND SITE EXPLORATION IN EVALUATING THE LIQUEFACTION RESISTANCE OF SANDS AND SILTY SANDS

    E-print Network

    CONE PENETRATION TESTING AND SITE EXPLORATION IN EVALUATING THE LIQUEFACTION RESISTANCE OF SANDS penetration tip resistance and liquefaction resistance of sandy soils are presented to facilitate use of the cone penetration test (CPT) in liquefaction studies. The proposed relationships are based on a database

  18. Lower Miocene (Upper Ottnangian) sands in the Lower Austrian Molasse Basin

    NASA Astrophysics Data System (ADS)

    Palzer, Markus; Knierzinger, Wolfgang; Wagreich, Michael; Gier, Susanne; Meszar, Maria Elisabeth; Soliman, Ali

    2015-04-01

    In the Early Miocene (late Ottnangian), a global sea level drop and the continuous rise of the Alps lead to the regression of the Parathethys sea, and to the sedimentation of the Upper Freshwater Molasse. In the Lower Austrian Molasse Basin, this event is represented by yellowish-brownish to greyish white mica-rich and carbonate-free sands and silts with clayish interlayers, formerly called Oncophora Beds (OB), which crop out between St. Pölten and Tulln. A new lithostratigraphy combines these sediments, now called Traisen-Formation (TF) together with the Dietersdorf Formation within the Pixendorf Group. Drill cores from OMV-wells predominantly from the NE show hundreds of meters thick sequences of pelites with intersections of sands interpreted as representing the OB. Contrary to the mainly brackish TF, a turbiditic marine deeper-water environment is inferred. An OMV-funded project investigates the relationship between these sediments, their stratigraphical and chronological range, provenance, facies and internal stratigraphy. First results from outcrops and several wells in the NE confirm large differences in grain size, structures and carbonate content. XRD-results indicate quartz, feldspar, muscovite, chlorite, calcite and dolomite as the main minerals within the sands and pelites. Pyrite is frequent. Halite and kaolinite occur. Whole rock chemistry, carbonate content measurements and biostratigraphic investigations of samples from the Wildendürnbach K4 well indicate, that these turbiditic OB can be divided into two sections: A lower fossil-free, carbonate poor and probably brackish (indicated by B/Al* and TOC/S) section with only few turbiditic very fine sands, and an upper microfossil bearing, marine section with carbonate contents up to 30% and more and coarser turbiditic sands. Therefore we use the working terms Lower and Upper Wildendürnbach Member (LWM, UWM). The lower part is enriched in (redox sensitive) heavy minerals such as Ce, Co, Cr, Cu, Gd, Ni, Pb, Sc, Zn and REE. It shows much lower constant Sr (about 140 ppm) values and B/Al* ratios (about 80) than the upper part (150 - 250 ppm; >120). The TOC/S ratio is much higher (17-23) in the LWM than in the UWM (>5). These two members can be correlated quite well by SP-logs over several wells. Therefore it can be concluded, that the lower part represents a period of salinity and carbonate crisis which may correspond to an (more or less) isolated deep basin probably poor in oxygen. At the beginning of the upper interval, a connection with the open sea was reestablished.

  19. 'Snow White' Trench

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on Sol 43, the 43rd Martian day after landing (July 8, 2008). This image shows the trench informally called 'Snow White.'

    Two samples were delivered to the Wet Chemistry Laboratory, which is part of Phoenix's Microscopy, Electrochemistry, and Conductivity Analyzer (MECA). The first sample was taken from the surface area just left of the trench and informally named 'Rosy Red.' It was delivered to the Wet Chemistry Laboratory on Sol 30 (June 25, 2008). The second sample, informally named 'Sorceress,' was taken from the center of the 'Snow White' trench and delivered to the Wet Chemistry Laboratory on Sol 41 (July 6, 2008).

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  20. SANDIA REPORT SAND 2009-0805

    E-print Network

    Kolda, Tamara G.

    in Cybersecurity Daniel M. Dunlavy, Bruce Hendrickson, and Tamara G. Kolda Prepared by Sandia National Laboratories in Cybersecurity Daniel M. Dunlavy and Bruce Hendrickson Sandia National Laboratories P.O. Box 5800, Mail Stop 1318 94550 Abstract This white paper is a response to a recent report on cybersecurity submitted to the U

  1. Bacteria transport through goethite-coated sand: Effects of solution pH and coated sand content

    Microsoft Academic Search

    Song-Bae Kim; Seong-Jik Park; Chang-Gu Lee; Nag-Choul Choi; Dong-Ju Kim

    2008-01-01

    This study investigated the transport of bacteria through goethite-coated sand, focusing on the effects of solution pH and coated sand content on the transport of Escherichia coli ATCC 11105. The first set of column experiments was performed in columns (length 30cm, diameter 5cm) packed with quartz sand coated with goethite in solution having a pH in the range of 6–9.

  2. White Dwarfs in Globular Clusters

    E-print Network

    S. Moehler; G. Bono

    2011-06-30

    We review empirical and theoretical findings concerning white dwarfs in Galactic globular clusters. Since their detection is a critical issue we describe in detail the various efforts to find white dwarfs in globular clusters. We then outline the advantages of using cluster white dwarfs to investigate the formation and evolution of white dwarfs and concentrate on evolutionary channels that appear to be unique to globular clusters. We also discuss the usefulness of globular cluster white dwarfs to provide independent information on the distances and ages of globular clusters, information that is very important far beyond the immediate field of white dwarf research. Finally, we mention possible future avenues concerning globular cluster white dwarfs, like the study of strange quark matter or plasma neutrinos.

  3. White-collar delinquency

    Microsoft Academic Search

    Henry N. Pontell; Stephen M. Rosoff

    2009-01-01

    Seemingly harmless pranks by computer hackers have evolved into major economic crimes and acts of terrorism that appear far\\u000a different than traditional forms of juvenile delinquency. Nonetheless, because they do not occupy the high status positions\\u000a that facilitate white-collar crimes, serious computer crimes by juveniles have fallen between the theoretical cracks. A new\\u000a hybrid category of crime that we label

  4. DUSEL Theory White Paper

    E-print Network

    S. Raby; T. Walker; K. S. Babu; H. Baer; A. B. Balantekin; V. Barger; Z. Berezhiani; A. de Gouvea; R. Dermisek; A. Dolgov; P. Fileviez Perez; G. Gabadadze; A. Gal; P. Gondolo; W. Haxton; Y. Kamyshkov; B. Kayser; E. Kearns; B. Kopeliovich; K. Lande; D. Marfatia; R. N. Mohapatra; P. Nath; Y. Nomura; K. A. Olive; J. Pati; S. Profumo; R. Shrock; Z. Tavartkiladze; K. Whisnant; L. Wolfenstein

    2008-10-24

    The NSF has chosen the site for the Deep Underground Science and Engineering Laboratory (DUSEL) to be in Lead, South Dakota. In fact, the state of South Dakota has already stepped up to the plate and contributed its own funding for the proposed lab, see http://www.sanfordlaboratoryathomestake.org/index.html. The final decision by NSF for funding the Initial Suite of Experiments for DUSEL will be made early in 2009. At that time the NSF Science Board must make a decision. Of order 200 experimentalists have already expressed an interest in performing experiments at DUSEL. In order to assess the interest of the theoretical community, the Center for Cosmology and Astro-Particle Physics (CCAPP) at The Ohio State University (OSU) organized a 3-day DUSEL Theory Workshop in Columbus, Ohio from April 4 - 6, 2008. The workshop focused on the scientific case for six proposed experiments for DUSEL: long baseline neutrino oscillations, proton decay, dark matter, astrophysical neutrinos, neutrinoless double beta decay and N-Nbar oscillations. The outcome of this workshop is the DUSEL Theory White paper addressing the scientific case at a level which may be useful in the decision making process for policy makers at the NSF and in the U.S. Congress. In order to assess the physics interest in the DUSEL project we have posted the DUSEL Theory White paper on the following CCAPP link http://ccapp.osu.edu/whitepaper.html . Please read the white paper and, if you are interested, use the link to show your support by co-signing the white paper.

  5. Planetesimals Around White Dwarfs

    NASA Astrophysics Data System (ADS)

    Xu, Siyi

    Evidence is convincing that a big fraction of extrasolar planetesimals can survive the red giant stage of a star and persist into the white dwarf phase. We argue that eventually, some of them do get perturbed into the tidal radius of the white dwarf and disrupted, creating a dusk disk and polluting the star's pure hydrogen or helium atmosphere at the same time. I have been performing multi-wavelength observations to study these intriguing systems. With Spitzer/IRAC, I find a depletion of dust disk around cool white dwarfs relative to the warmer sample, possibly due to accretion from cometary objects. With the Cosmic Origins Spectrograph (COS) onboard the Hubble Space Telescope and the High- Resolution Echelle Spectrometer (HIRES) on Keck, I find that to zeroth order, the elemental compositions of extrasolar planetesimals very much resemble that of bulk Earth. A more detailed comparison with the solar system meteorites shows that post-nebular processing is common among extrasolar planetesimals. Overall, the bulk composition of Earth is normal compared to the current sample of extrasolar planetesimals.

  6. Faecal indicator bacteria enumeration in beach sand: A comparison study of extraction methods in medium to coarse sands

    USGS Publications Warehouse

    Boehm, A.B.; Griffith, J.; McGee, C.; Edge, T.A.; Solo-Gabriele, H. M.; Whitman, R.; Cao, Y.; Getrich, M.; Jay, J.A.; Ferguson, D.; Goodwin, K.D.; Lee, C.M.; Madison, M.; Weisberg, S.B.

    2009-01-01

    Aims: The absence of standardized methods for quantifying faecal indicator bacteria (FIB) in sand hinders comparison of results across studies. The purpose of the study was to compare methods for extraction of faecal bacteria from sands and recommend a standardized extraction technique. Methods and Results: Twenty-two methods of extracting enterococci and Escherichia coli from sand were evaluated, including multiple permutations of hand shaking, mechanical shaking, blending, sonication, number of rinses, settling time, eluant-to-sand ratio, eluant composition, prefiltration and type of decantation. Tests were performed on sands from California, Florida and Lake Michigan. Most extraction parameters did not significantly affect bacterial enumeration. anova revealed significant effects of eluant composition and blending; with both sodium metaphosphate buffer and blending producing reduced counts. Conclusions: The simplest extraction method that produced the highest FIB recoveries consisted of 2 min of hand shaking in phosphate-buffered saline or deionized water, a 30-s settling time, one-rinse step and a 10 : 1 eluant volume to sand weight ratio. This result was consistent across the sand compositions tested in this study but could vary for other sand types. Significance and Impact of the Study: Method standardization will improve the understanding of how sands affect surface water quality. ?? 2009 The Society for Applied Microbiology.

  7. Zebra processes of oil recovery using fireflood and waterflood in alternate sands in a multi-sand environment

    SciTech Connect

    Chu, C. [Texaco, Inc., Houston, TX (United States)

    1995-12-31

    This paper presents a new process of oil recovery, namely, the zebra process, which is specifically advantageous to use in heavy oil reservoirs that exist in multiple sands. This process uses firefloods and waterfloods in alternate sands. The firefloods serve as formation preheaters which reduce the oil viscosities in the neighboring sands so that these sands, normally not amenable to waterfloods because of high viscosity, can be waterflooded with ease. The exciting news is that the air compression cost in firefloods can be reduced by a factor of three with a proper application of the zebra process. This great savings in air compression cost is possible because the heat that is normally lost to the overburden and underburden in firefloods is now being put to good use, by preheating the neighboring sands. Examples are given on zebraing several idealized sand-shale sequences involving three-, five-, six-, and seven-sand reservoirs, and also zebraing two actual sand-shale sequences, both involving five-sand reservoirs.

  8. CAA white paper streamlines multiple requirements

    SciTech Connect

    Bassett, S.M.

    1996-05-01

    Developed in conjunction with California regulators, EPA has released a second white paper designed to streamline the Title V operating permit program. The paper, White Paper Number 2 for Improved Implementation of the Part 70 Operating Permits Program, was released March 5, 1996. The guidance explains approaches for facility owners and permitting authorities to: streamline multiple applicable requirements; deal with outdated state implementation plan (SIP) provisions; handle permit provisions for insignificant emission units (IEUs); stipulate facility status with regard to applicable requirements; and cross-reference pertinent information in permits and applications. While these streamlining approaches can give facilities much-needed flexibility, EPA imposes significant restrictions on their use. Due to the complexity of the guidance and its length, this article describes only the first streamlining method, reducing multiple requirements.

  9. Greening of the White House: Six year report

    SciTech Connect

    None

    1999-11-01

    The White House, which recently celebrated its 200th birthday, has a long tradition of demonstrating technological innovation. In keeping with that tradition, President Clinton announced the Greening of the White House Initiative on Earth Day 1993. The initiative improves the energy and environmental performance of the White House complex by identifying opportunities to reduce waste, lower energy use, and make an appropriate use of renewable resources, all while improving indoor air quality and building comfort. This report on President Clinton's legacy of greening at the White House summarizes progress made to date and gives an overview of new opportunities identified during the past year. It also includes an environmental history of the White House and a short tour of the buildings that make up the White House complex. Over the past five years, this initiative has involved hundreds of dedicated people from both within and outside government. A description of how they worked together to develop and implement the Greening Plan is also included in this report.

  10. Microstructural characterization of a Canadian oil sand

    E-print Network

    Dinh, Hong Doan; Nauroy, Jean-François; Tang, Anh-Minh; Souhail, Youssef; 10.1139/T2012-072

    2013-01-01

    The microstructure of oil sand samples extracted at a depth of 75 m from the estuarine Middle McMurray formation (Alberta, Canada) has been investigated by using high resolution 3D X-Ray microtomography ($\\mu$CT) and Cryo Scanning Electron Microscopy (CryoSEM). $\\mu$CT images evidenced some dense areas composed of highly angular grains surrounded by fluids that are separated by larger pores full of gas. 3D Image analysis provided in dense areas porosity values compatible with in-situ log data and macroscopic laboratory determinations, showing that they are representative of intact states. $\\mu$CT hence provided some information on the morphology of the cracks and disturbance created by gas expansion. The CryoSEM technique, in which the sample is freeze fractured within the SEM chamber prior to observation, provided pictures in which the (frozen) bitumen clearly appears between the sand grains. No evidence of the existence of a thin connate water layer between grains and the bitumen, frequently mentioned in th...

  11. Removal of microcystins by slow sand filtration.

    PubMed

    Grützmacher, Gesche; Böttcher, Gabriele; Chorus, Ingrid; Bartel, Hartmut

    2002-01-01

    To assess the elimination potential of slow sand filters for cyanobacterial hepatotoxins (microcystins), two full-scale experiments were conducted using the German Federal Environment Agency's experimental field in Berlin, Germany. One experiment was carried out with dissolved microcystins extracted from a cyanobacterial bloom on one of Berlin's lakes, dosed as short-term, single-pulse application. The other experiment simulated natural conditions more closely, with a longer-term exposure of the filter to living cyanobacterial cells (collected from the same lake) so that most toxins were initially contained inside the cells. The microcystins were detected by ELISA and HPLC/photodiode array detector and subsequently identified by MALDI-TOF MS. The experiment with dissolved microcystins yielded very high elimination rates (>95%) inside the filter bed attributed to biodegradation, whereas retardation by adsorption was low. The obtained half-lives for the microcystins detected by ELISA were about 1 h. The second experiment, which was with mostly cell-bound microcystins, showed similar results during the first days after application of cyanobacteria (elimination >85%). As the population declined in late autumn, the proportion of extracellular to cell-bound microcystins increased. At the same time the elimination rates declined to values <60%. This decline is most likely attributable to retarded biodegradation at temperatures of <4 degrees C. Altogether the results of the experiments show that under moderate temperatures, with an intact schmutzdecke (biofilm) with previous contact with microcystins, slow sand filtration is an effective treatment for eliminating microcystins from drinking water. PMID:12203961

  12. Avalanches of Singing Sand in the Laboratory

    NASA Astrophysics Data System (ADS)

    Dagois-Bohy, Simon; Courrech Du Pont, Sylvain; Douady, Stéphane

    2011-03-01

    The song of dunes is a natural phenomenon that has arisen travellers' curiosity for a long time, from Marco Polo to R.A. Bagnold. Scientific observations in the XXth century have shown that the sound is emitted during a shear flow of these particular grains, the free surface of the flow having coherent vibrations like a loud speaker. The sound emission is also submitted to a threshold effect with many parameters like humidity, flow speed, surface of the grains. The sound has been reproduced in laboratory avalanche experiments close to the natural phenomenon on field, but set in a channel with a hard bottom and a few centimeters of sand flowing, which contradicts explanations of the sound that involve a sand dune under the avalanche flow. Flow rates measurements also show the presence of a plug region in the flow above the sheared band, with the same characteristic length as the coherence zones of the sound. Finally we show experimentally that the Froude number, once modified to take into account the height of this plug band, is the parameter that sets the amplitude of the sound, and produces a threshold that depends on the grain type.

  13. 40 CFR 436.40 - Applicability; description of the industrial sand subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the industrial sand subcategory. 436.40 Section 436...PROCESSING POINT SOURCE CATEGORY Industrial Sand Subcategory § 436.40 Applicability; description of the industrial sand subcategory. The provisions of...

  14. 40 CFR 436.30 - Applicability; description of the construction sand and gravel subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the construction sand and gravel subcategory. 436.30 Section...PROCESSING POINT SOURCE CATEGORY Construction Sand and Gravel Subcategory § 436.30 Applicability; description of the construction sand and gravel subcategory. The...

  15. 43 CFR 3141.2 - Prelease exploration within Special Tar Sand Areas.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false Prelease exploration within Special Tar Sand Areas. 3141.2 Section 3141.2 Public...MINERALS MANAGEMENT (3000) LEASING IN SPECIAL TAR SAND AREAS Leasing in Special Tar Sand Areas § 3141.2 Prelease exploration...

  16. 32 CFR 644.505 - Disposal plan for embedded gravel, sand or stone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...true Disposal plan for embedded gravel, sand or stone. 644.505 Section 644...Standing Timber, Crops, and Embedded Gravel, Sand and Stone § 644.505 Disposal plan for embedded gravel, sand or stone. Prior to offering...

  17. 43 CFR 3141.2 - Prelease exploration within Special Tar Sand Areas.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false Prelease exploration within Special Tar Sand Areas. 3141.2 Section 3141.2 Public...MINERALS MANAGEMENT (3000) LEASING IN SPECIAL TAR SAND AREAS Leasing in Special Tar Sand Areas § 3141.2 Prelease exploration...

  18. 43 CFR 3141.2 - Prelease exploration within Special Tar Sand Areas.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false Prelease exploration within Special Tar Sand Areas. 3141.2 Section 3141.2 Public...MINERALS MANAGEMENT (3000) LEASING IN SPECIAL TAR SAND AREAS Leasing in Special Tar Sand Areas § 3141.2 Prelease exploration...

  19. 40 CFR 436.30 - Applicability; description of the construction sand and gravel subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Applicability; description of the construction sand and gravel subcategory. 436.30 Section...PROCESSING POINT SOURCE CATEGORY Construction Sand and Gravel Subcategory § 436.30 Applicability; description of the construction sand and gravel subcategory. The...

  20. 32 CFR 644.505 - Disposal plan for embedded gravel, sand or stone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...true Disposal plan for embedded gravel, sand or stone. 644.505 Section 644...Standing Timber, Crops, and Embedded Gravel, Sand and Stone § 644.505 Disposal plan for embedded gravel, sand or stone. Prior to offering...

  1. 40 CFR 436.40 - Applicability; description of the industrial sand subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Applicability; description of the industrial sand subcategory. 436.40 Section 436...PROCESSING POINT SOURCE CATEGORY Industrial Sand Subcategory § 436.40 Applicability; description of the industrial sand subcategory. The provisions of...

  2. 32 CFR 644.505 - Disposal plan for embedded gravel, sand or stone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...false Disposal plan for embedded gravel, sand or stone. 644.505 Section 644...Standing Timber, Crops, and Embedded Gravel, Sand and Stone § 644.505 Disposal plan for embedded gravel, sand or stone. Prior to offering...

  3. 43 CFR 3141.2 - Prelease exploration within Special Tar Sand Areas.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false Prelease exploration within Special Tar Sand Areas. 3141.2 Section 3141.2 Public...MINERALS MANAGEMENT (3000) LEASING IN SPECIAL TAR SAND AREAS Leasing in Special Tar Sand Areas § 3141.2 Prelease exploration...

  4. 40 CFR 436.40 - Applicability; description of the industrial sand subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the industrial sand subcategory. 436.40 Section 436...PROCESSING POINT SOURCE CATEGORY Industrial Sand Subcategory § 436.40 Applicability; description of the industrial sand subcategory. The provisions of...

  5. 32 CFR 644.505 - Disposal plan for embedded gravel, sand or stone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...false Disposal plan for embedded gravel, sand or stone. 644.505 Section 644...Standing Timber, Crops, and Embedded Gravel, Sand and Stone § 644.505 Disposal plan for embedded gravel, sand or stone. Prior to offering...

  6. 40 CFR 436.30 - Applicability; description of the construction sand and gravel subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Applicability; description of the construction sand and gravel subcategory. 436.30 Section...PROCESSING POINT SOURCE CATEGORY Construction Sand and Gravel Subcategory § 436.30 Applicability; description of the construction sand and gravel subcategory. The...

  7. 77 FR 60207 - Endangered and Threatened Wildlife and Plants; Proposed Threatened Status for Coral Pink Sand...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-02

    ...Plants; Proposed Threatened Status for Coral Pink Sand Dunes Tiger Beetle and Designation...Plants; Proposed Threatened Status for Coral Pink Sand Dunes Tiger Beetle and Designation...Service (Service) propose to list the Coral Pink Sand Dunes tiger beetle,...

  8. Virus retention and transport through Al-oxide coated sand columns: effects of ionic strength and composition

    NASA Astrophysics Data System (ADS)

    Zhuang, Jie; Jin, Yan

    2003-02-01

    Knowledge of the factors that influence the fate and transport of viruses in porous media is very important for accurately determining groundwater vulnerability and for developing protective regulations. In this study, six saturated sand column experiments were performed to examine the effects of a positively charged Al-oxide, which was coated on sand particles, on the retention and transport of viruses (?X174 and MS-2) in background solutions of different ionic strength and composition. We found that the Al-oxide coating on sand significantly removed viruses during their transport in a phosphate buffered saline (PBS) solution. Mass balance calculations showed that 34% of the input MS-2 was inactivated/irreversibly sorbed on the surface of Al-oxide coated sand whereas 100% of ?X174 was recovered. Results from this study also indicated that higher ionic strength facilitated the transport of both ?X174 and MS-2 through the Al-oxide coated sand. This was attributed to the effect of ion shielding, which at higher ionic strength decreased the electrostatic attraction between the viral particles and the sand surface and consequently decreased virus sorption. Strong effect of the ionic strength indicates that an outer-sphere complexation mechanism was responsible for the virus sorption on the Al-oxide coated sand. Ion composition of the background solutions was also found to be a significant factor in influencing virus retention and transport. Virus transport was enhanced in the presence of phosphate (HPO 42-) as compared to bicarbonate (HCO 3-), and the effect of HPO 42- was more significant on MS-2 than on ?X174. The presence of bivalent cations (Ca 2+ and Mg 2+) increased virus transport because the cations partially screened the negative charges on the viruses therefore decreased the electrostatic attraction between the positively charged sand surface and the negatively charged viruses. Mass recovery data indicated that bivalent cations gave rise to a certain degree of inactivation/irreversibly sorption of ?X174 on the surface of Al-oxide coated sand. On the contrary, the bivalent cations appeared to have protected MS-2 from inactivation/irreversibly sorption. This study provides some insights into the mechanisms responsible for virus retention and transport in porous media.

  9. Household scale slow sand filtration in the Dominican Republic

    E-print Network

    Donison, Kori S. (Kori Shay), 1981-

    2004-01-01

    Slow sand filtration is a method of water treatment that has been used for hundreds of years. In the past two decades, there has been resurgence in interest in slow sand filtration, particularly as a low-cost, household-scale ...

  10. The extraction of bitumen from western tar sands

    SciTech Connect

    Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1990-07-01

    Topics discussed include: characterization of bitumen impregnated sandstone, water based tar sand separation technology, electrophoretic characterization of bitumen and fine mineral particles, bitumen and tar sand slurry viscosity, the hot water digestion-flotation process, electric field use on breaking water-in-oil emulsions, upgrading of bitumens and bitumen-derived liquids, solvent extraction.

  11. The extraction of bitumen from western tar sands. Annual report

    SciTech Connect

    Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

    1990-07-01

    Topics discussed include: characterization of bitumen impregnated sandstone, water based tar sand separation technology, electrophoretic characterization of bitumen and fine mineral particles, bitumen and tar sand slurry viscosity, the hot water digestion-flotation process, electric field use on breaking water-in-oil emulsions, upgrading of bitumens and bitumen-derived liquids, solvent extraction.

  12. 20. View of sand filtration bed. Wheelbarrow was used to ...

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

    20. View of sand filtration bed. Wheelbarrow was used to remove schmutzdeck (top, dirty sand layer containing particulate contamination, dead microorganisms and debris) for cleaning and or disposal. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  13. Sugarcane Genotype Selection for Sand Soils in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Selection of high yielding sugarcane (Saccharum spp.) genotypes for organic (muck) soils in Florida has been more successful than for sand soils. The purpose of this study was to compare the performance of 31 sugarcane genotypes on sand soils with and without mill mud added at the rate of 1510 cubic...

  14. Cotton seedling abrasion and recovery from wind blown sand

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Millions of hectares of crops are exposed to wind blown sand abrasion each year and in many instances the damage is thought to be severe enough to require replanting. The goal of this study was to determine the effects of wind blown sand abrasion duration on cotton (Gossypium hirsutum L.) seedlings...

  15. Reovirus removal and inactivation by slow-rate sand filtration.

    PubMed

    McConnell, L K; Sims, R C; Barnett, B B

    1984-10-01

    Laboratory column studies were conducted at the Utah Water Research Laboratory, Logan, Utah, to evaluate reovirus removal from drinking water supplies by slow-rate sand filtration (SSF). Columns, constructed to simulate a full-scale SSF field operation, were inoculated with reovirus at ca. 1,000-times-greater concentrations than those typically found in domestic sewage. Reovirus removal and inactivation were investigated as functions of filter maturity and other filter sand characteristics. Reovirus removal studies demonstrated that the SSF process is capable of reducing reovirus in influent water by a minimum of 4 log concentration units under certain conditions of water quality, flow rate, and sand bed construction. Infectious reovirus was not detected in effluent samples from any of the sand beds studied, after inoculation of the SSF columns; therefore, removal efficiencies were not affected significantly by characteristics, including age, of the two filter sands evaluated. Studies conducted with radioactively labeled reovirus demonstrated that reovirus removed from influent water was distributed throughout the entire length of the filter beds. Concentrations of reovirus in the filter sands decreased with increasing bed depth. The greatest removal occurred in the top few centimeters of all sand beds. No infectious reovirus could be detected in clean or mature sand bed media, indicating that reoviruses were inactivated in the filter. PMID:6508290

  16. 31. PETIBONE SAND THROWING MACHINE BOX FLOOR GREY IRON FOUNDRY ...

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

    31. PETIBONE SAND THROWING MACHINE BOX FLOOR GREY IRON FOUNDRY FORCES CONDITIONED MOLDING SAND, AT HIGH VELOCITY, INTO MOLDS TOO BIG TO BE MADE ON ONE OF THE CONVEYOR SYSTEMS. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  17. Sand Tray and Group Therapy: Helping Parents Cope

    ERIC Educational Resources Information Center

    James, Linda; Martin, Don

    2002-01-01

    Sand tray with group therapy can be an effective treatment approach for parents coping with adolescent substance abuse and/or dependency. Excerpts of parent sand trays are presented to demonstrate pretreatment tasks that decrease denial, reduce reactive anger, stop enabling behaviors, and build support systems. Parent-child relational issues,…

  18. Spatial variability of flow parameters in a stratified sand

    Microsoft Academic Search

    Leslie Smith

    1981-01-01

    The spatial variability in porosity, hydraulic conductivity, compressibility, and various grain size fractions is analyzed for several sets of samples from the Quadra Sand. This unit is a well-sorted, medium grained, horizontally stratified sand with relatively few silt or gravel interbeds. Both random and uniformly spaced sample plans are used. The heterogeneity of the flow parameters is characterized by frequency

  19. Study of properties of sand asphalt using a torsional rheometer

    E-print Network

    Kasula, Lavan Kumar Reddy

    2004-11-15

    . In this work we have used the same Torsional Rheometer with some minor modifications in the design to measure some general properties of Sand Asphalt mixtures. Sand Asphalt mixtures, due to their non-linear viscoelastic character, exhibit `normal stress effects...

  20. The recovery of backwash water from sand filters by ultrafiltration

    Microsoft Academic Search

    Chris Dotremont; Bart Molenberghs; Wim Doyen; Paul Bielen; Koen Huysman

    1999-01-01

    Groundwater is still one of the main sources for the production of drinking water. In the preparation of drinking water, the groundwater is first aerated and then filtered through a sand filter in order to remove Fe, Mn, NH4 and methane. After saturation, these sand filters have to be backwashed periodically. In the past, the backwash water was discharged in

  1. Hydraulic mining technique for recovering bitumen from tar sand deposit

    Microsoft Academic Search

    Redford

    1976-01-01

    Viscous petroleum including bitumen may be recovered for subterranean petroleum containing unconsolidated said formations such as tar sand deposits by hydraulic mining. Hot water or steam is introduced into the subterranean deposit with sufficient velocity to dislodge bitumen and particles of sand therefrom. The process is a single wellbore operation using rotatable vertically moveable injection string with one or more

  2. TECHNICAL NOTE Centrifuge cone penetration tests in sand

    E-print Network

    Bolton, Malcolm

    TECHNICAL NOTE Centrifuge cone penetration tests in sand M. D. BOLTON,Ã M. W. GUI,Ã J. GARNIER,{ J. F. CORTE,{ G. BAGGE,{ J. LAUE} and R. RENZIk KEYWORDS: centrifuge modelling; in-situ testing; laboratory tests; piles; sands. INTRODUCTION Centrifuges have been widely adopted in modelling geotechnical

  3. Beach Sand Analysis for Indicators of Microbial Contamination

    EPA Science Inventory

    Traditional beach monitoring has focused on water quality, with little attention paid to health risks associated with beach sand. Recent research has reported that fecal indicator bacteria, as well as human pathogens can be found in beach sand and may constitute a risk to human h...

  4. Canadian oil sands development: a blueprint for synthetic fuels commercialization

    Microsoft Academic Search

    Sen

    1979-01-01

    Four major oil sands deposits in Alberta hold an estimated trillion barrels of oil, nearly 200 billion of which are thought to be recoverable by known technologies. Oil sands will help Canada meet its goals of reducing imports in the face of dwindling oil field reserves if in-situ recovery technology can be brought to commercialization. Major environmental, economic, and institutional

  5. Extraction of vanadium from athabasca tar sands fly ash

    Microsoft Academic Search

    C. O. Gomez-Bueno; D. R. Spink; G. L. Rempel

    1981-01-01

    The production of refinery grade oil from the Alberta tar sands deposits as currently practiced by Suncor (formally Great Canadian Oil Sands Ltd.---GCOS) generates a substantial amount of petroleum coke fly ash which contains appreciable amounts of valuable metals such as vanadium, nickel and titanium. Although the recovery of vanadium from petroleum ash is a well established commercial practice, it

  6. Reclamation of disturbed land at Great Canadian Oil Sands

    Microsoft Academic Search

    T. D. Shopik; W. L. Cary

    1977-01-01

    Practical application of reclamation methods developed over 6 yr at an operating oil-sands plant is described. The details of numerous successes and failures in developing this methodology for overburden and tailings sand dikes in a northern boreal forest ecology are given. Seed-bed preparations, seeding methods, and follow up treatments are described. Unique equipment problems were encountered on the slopes of

  7. Sand abrasion injury and biomass partitioning in cotton seedlings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Millions of acres of crops are exposed to wind blown sand abrasion injury each year and in many instances the damage is thought to be sufficiently severe to require replanting. The goal of this study was to determine the effects of wind blown sand abrasion duration on cotton seedlings. Seedlings of ...

  8. SLOW SAND FILTER MAINTENANCE COSTS AND EFFECTS ON WATER QUALITY

    EPA Science Inventory

    A study was conducted to determine how slow sand filter effluent quality is affected by scraping and to quantify the labor required to operate and maintain a slow sand filter. The data were obtained by monitoring scraping and other maintenance operations at six full-size slow san...

  9. 12. INTERIOR VIEW WITH JAMES WILLIAMS REACHING FOR THE SAND ...

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

    12. INTERIOR VIEW WITH JAMES WILLIAMS REACHING FOR THE SAND RELEASE LEVER WHICH WILL OPEN THE OVERHEAD STORAGE BIN AND PERMIT A SET AMOUNT OF SAND TO BE DEPOSITED INTO THE FLASK PRIOR TO COMPRESSION BY THE MOLDING MACHINE INSIDE GREY IRON UNIT NO. 1. - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  10. The Unified Gravel-Sand (TUGS) Model: Simulating the Transport of Gravel-Sand Mixtures in Rivers

    NASA Astrophysics Data System (ADS)

    Cui, Y.

    2006-12-01

    TUGS Model was developed by employing the surface-based bedload equation of Wilcock and Crowe (2003) and linking grain size distributions in the bedload, surface layer, and subsurface sediment deposit with the gravel transfer function of Hoey and Ferguson (1994) and Toro-Escobar et al. (1996), and a hypothetical sand transfer function. The unmodified model was applied to simulate the sedimentation process in Marmot Reservoir, Sandy River, Oregon and produced similar stratified sediment deposit as observed through coring exercises. The model was also examined with three runs of large-scale flume experiments conducted at St. Anthony Falls Laboratory (SAFL) by Seal et al. (1995). With a very minor modification to Wilcock and Crowe (2003) equation, the model excellently reproduced the longitudinal profiles, gravel grain size distributions and sand fractions in the deposits for all the three SAFL runs. Following its examination, TUGS model was applied to simulate the sediment transport dynamics in the Sandy River, Oregon under a few hypothetical scenarios, focusing on the dynamics of sand fractions in gravel-bedded channel deposits. Results of the exploratory runs on the Sandy River indicate that (a) surface and subsurface sand fractions generally increase in the downstream direction, similar to observed in the field; (b) sand fraction in the deposit is positively correlated with sand supply as expected; (c) extremely high sand supply under similar gravel supply and hydrologic conditions can transform the river into predominantly sand-bedded; (d) increased discharge under the same sand and gravel supply conditions results in decreased sand fraction in the deposit as expected; and (e) there can be significant increase in surface and subsurface sand fractions in the backwater zones near the mouth of the river as expected.

  11. Genetic features of soils on sorted sand deposits of different origins in the Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Pereverzev, V. N.

    2009-09-01

    Differences in the chemical composition of soils developed from sorted sands of different origins are revealed. The iron-illuvial podzols on rich glaciofluvial and marine sands are characterized by well-pronounced Al-Fe-humus differentiation of the Si, Al, and Fe in the soil profile. These soils are relatively similar in their bulk elemental composition. The difference between them is seen in the degree of differentiation of the soil profiles; it is stronger in the soils developed from glaciofluvial deposits. This is particularly true with respect to the oxalate-soluble iron and aluminum hydroxides. The deposits derived from the red-colored Tersk sandstone and processed by the sea (in the coastal zone of the White Sea) have the poorest chemical composition. In the soils developed from them, the differentiation of oxalate-soluble compounds is slightly pronounced (for Fe) or completely absent (for Si and Al). These soils can be classified as podzolized ferruginous red-colored psammozems (within the order of poorly developed soils) with the following horizons: O-Ce-Cf-C. The Ce horizon has the features of podzolization, and the Cf horizon has some features attesting to the illuvial accumulation of Fe. The profile of these soils inherits a reddish tint from the parent material.

  12. Process and apparatus for recovery of oil from tar sands

    SciTech Connect

    Brewer, J.C.

    1982-11-30

    A crude oil product is extracted from a tar sand by first crushing the tar sand as mined and then fine grinding the crushed material in a grinding mill in the presence of a cleansing liquid, such as an aqueous solution of a caustic. The resulting slurry is passed into suitable extractor-classifier equipment, such as that shown in U.S. Pat. No. 3,814,336, in which a body of cleansing liquid is maintained. Agitation of the slurry in such maintained body of cleansing liquid substantially completes removal of the bituminous matter from the sand, and the resulting crude oil and cleansing liquid phase is discharged separately from the sand solid phase. The liquid phase is treated for the removal of residual sand particles and for the separation of residual cleansing liquid from the crude oil. The cleansing liquid so recovered is recycled and the crude oil is passed to further processing or for use as such.

  13. Method and apparatus for hydrocarbon recovery from tar sands

    DOEpatents

    Westhoff, J.D.; Harak, A.E.

    1988-05-04

    A method and apparatus for utilizing tar sands having a broad range of bitumen content is disclosed. More particularly, tar sands are pyrolyzed in a cyclone retort with high temperature gases recycled from the cyclone retort to produce oil and hydrocarbon products. The spent tar sands are then burned at 2000/degree/F in a burner to remove residual char and produce a solid waste that is easily disposable. The process and apparatus have the advantages of being able to utilize tar sands having a broad range of bitumen content and the advantage of producing product gases that are free from combustion gases and thereby have a higher heating value. Another important advantage is rapid pyrolysis of the tar sands in the cyclone so as to effectively utilize smaller sized reactor vessels for reducing capitol and operating costs. 1 fig., 1 tab.

  14. Mapping sand and gravel pits in the Patuxent River watershed

    NASA Technical Reports Server (NTRS)

    Schmidt, T. J.; Witt, R. G.

    1981-01-01

    LANDSAT data from July 1973 and June 1978 for the Patuxent River Watershed of Maryland were processed in an effort to devise an economical method of monitoring the reclamation of sand and gravel pits. ASTEP-II and IDIMS software were utilized to derive signatures for sand and gravel pits and other land use/land cover types. Both unsupervised and supervised classifications of the two data sets were produced. Resultant statistics and color output products were compared in order to determine the extent of reclamation and expansion of sand and gravel pits over the five-year time span and to check the locations of more recent sand and gravel pits. Preliminary results indicate that, for a selected northern sub-acre, signatures derived for sand and gravel pits were nearly 90 percent accurate.

  15. Method and apparatus for hydrocarbon recovery from tar sands

    DOEpatents

    Westhoff, James D. (Laramie, WY); Harak, Arnold E. (Laramie, WY)

    1989-01-01

    A method and apparatus for utilizing tar sands having a broad range of bitumen content is disclosed. More particularly, tar sands are pyrolyzed in a cyclone retort with high temperature gases recycled from the cyclone retort to produce oil and hydrocarbon products. The spent tar sands are then burned at 2000.degree. F. in a burner to remove residual char and produce a solid waste that is easily disposable. The process and apparatus have the advantages of being able to utilize tar sands having a broad range of bitumen content and the advantage of producing product gases that are free from combustion gases and thereby have a higher heating value. Another important advantage is rapid pyrolysis of the tar sands in the cyclone so as to effectively utilize smaller sized reactor vessels for reducing capitol and operating costs.

  16. Aerodynamics and morphodynamics of sand fences: A review

    NASA Astrophysics Data System (ADS)

    Li, Bailiang; Sherman, Douglas J.

    2015-06-01

    This paper reviews literature on the aerodynamics and morphodynamics of sand fences. We consider both wind fences for reducing wind erosion, and sand-trapping fences for controlling sand deposition. There has been substantial trial-and-error research based upon installations of sand fences, but only limited research on the fence and site attributes that provide the main aerodynamic and morphodynamic controls of interactions between aeolian systems and the fences. Such attributes include: fence porosity, height, length, width, opening size and geometry, porosity distribution, and external factors such as incoming flow characteristics, roughness length, atmospheric stability, grain size and local landform change. Considerations for the optimal design for both wind fences and sand-trapping fences are presented.

  17. Sand control in horizontal wells in heavy-oil reservoirs

    SciTech Connect

    Islam, M.R. (Nova Husky Research Corp. (CA)); George, A.E. (Energy, Mines, and Resources (CA))

    1991-07-01

    Recent advances in horizontal-well technology has greatly improved the potential for heavy oil recovery. Such recovery may be hampered, however, by sanding problems associated with most heavy-oil reservoirs. These reservoir sands are mostly unconsolidated and may lead to severe productivity-loss problems if produced freely. This paper offers recommendations for sand control in three Canadian heavy-oil reservoirs. Experimental evidence has shown that minimizing the annular space between the casing and the open hole is important, especially in the case of smaller wire space, lower oil viscosity, and thinner pay zone. Several types of wire-wrapped screens and flexible liners were tested for sand control. Only flexible liners reduced sand production to a negligible amount.

  18. Mathematics Written in Sand Version of 22 Nov. 1983 File MathSand.pdf January 9, 2001 8:40 am Page 1 /49

    E-print Network

    California at Irvine, University of

    Mathematics Written in Sand Version of 22 Nov. 1983 File MathSand.pdf January 9, 2001 8:40 am Page 1 /49 MATHEMATICS WRITTEN IN SAND - the hp-15C, Intel 8087, etc. W. Kahan, University of California;Mathematics Written in Sand Version of 22 Nov. 1983 File MathSand.pdf January 9, 2001 8:40 am Page 2 /49 Three

  19. The Lowest Mass White Dwarf

    E-print Network

    Mukremin Kilic; Carlos Allende Prieto; Warren R. Brown; D. Koester

    2007-02-13

    Extremely low mass white dwarfs are very rare objects likely formed in compact binary systems. We present MMT optical spectroscopy of 42 low mass white dwarf candidates serendipitously discovered in a survey for hypervelocity B-type stars. One of these objects, SDSS J0917+46, has Teff= 11,288 \\pm 72 K and log g = 5.48 \\pm 0.03; with an estimated mass of 0.17 M_sun, it is the lowest gravity/mass white dwarf currently known. However, 40 of the low mass candidates are normal DA white dwarfs with apparently inaccurate SDSS g magnitudes. We revisit the identification of low mass white dwarf candidates previously found in the SDSS, and conclude that four objects have M white dwarfs show excess emission from a binary companion, and radial velocity searches will be necessary to constrain the nature of the unseen companions.

  20. Sand waves on an epicontinental shelf: Northern Bering Sea

    USGS Publications Warehouse

    Field, M.E.; Nelson, C.H.; Cacchione, D.A.; Drake, D.E.

    1981-01-01

    Sand waves and current ripples occupy the crests and flanks of a series of large linear sand ridges (20 km ?? 5 km ?? 10 m high) lying in an open-marine setting in the northern Bering Sea. The sand wave area, which lies west of Seward Peninsula and southeast of Bering Strait, is exposed to the strong continuous flow of coastal water northward toward Bering Strait. A hierarchy of three sizes of superimposed bedforms, all facing northward, was observed in successive cruises in 1976 and 1977. Large sand waves (height 2 m; spacing 200 m) have smaller sand waves (height 1 m; spacing 20 m) lying at a small oblique angle on their stoss slopes. The smaller sand waves in turn have linguoid ripples on their stoss slopes. Repeated studies of the sand wave fields were made both years with high-resolution seismic-reflection profiles, side-scan sonographs, underwater photographs, current-meter stations, vibracores, and suspended-sediment samplers. Comparison of seismic and side-scan data collected along profile lines run both years showed changes in sand wave shape that indicate significant bedload transport within the year. Gouge marks made in sediment by keels of floating ice also showed significantly different patterns each year, further documenting modification to the bottom by sediment transport. During calm sea conditions in 1977, underwater video and camera observations showed formation and active migration of linguoid and straight-crested current ripples. Current speeds 1 m above the bottom were between 20 and 30 cm/s. Maximum current velocities and sand wave migration apparently occur when strong southwesterly winds enhance the steady northerly flow of coastal water. Many cross-stratified sand bodies in the geologic record are interpreted as having formed in a tidal- or storm-dominated setting. This study provides an example of formation and migration of large bedforms by the interaction of storms with strong uniform coastal currents in an open-marine setting. ?? 1981.