WorldWideScience

Sample records for surface composition mapping

  1. Remote compositional mapping of lunar titanium and surface maturity

    Science.gov (United States)

    Johnson, J. R.; Larson, S. M.; Singer, Robert B.

    1991-01-01

    Lunar ilmenite (FeTiO3) is a potential resource capable of providing oxygen for life support and spacecraft propellant for future lunar bases. Estimates of TiO2 content in mature mare soils can be made using an empirical relation between the 400/500 nm reflectance ratio and TiO2 wt percent. A TiO2 abundance map was constructed for the entire near-side lunar maria accurate to + or - 2 wt percent TiO2 using CCD images obtained at the Tumamoc Hill 0.5 m telescope in Tucson, employing bandpass filters centered at 400 and 560 nm. Highest TiO2 regions in the maria are located in western Mare Tranquillitatis. Greater contrast differences between regions on the lunar surface can be obtained using 400/730 nm ratio images. The relation might well be refined to accommodate this possibly more sensitive indicator of TiO2 content. Another potential lunar resource is solar wind-implanted He-3 which may be used as a fuel for fusion reactors. Relative soil maturity, as determined by agglutinate content, can be estimated from 950/560 nm ration images. Immature soils appear darker in this ratio since such soils contain abundant pyroxene grains which cause strong absorption centered near 950 nm due Fe(2+) crystal field transitions. A positive correlation exists between the amount of He-3 and TiO2 content in lunar soils, suggesting that regions high in TiO2 should also be high in He-3. Reflectance spectrophotometry in the region 320 to 870 nm was also obtained for several regions. Below about 340 nm, these spectra show variations in relative reflectance that are caused by as yet unassigned near-UV absorptions due to compositional differences.

  2. Mapping Precipitation Patterns from the Stable Isotopic Composition of Surface Waters: Olympic Peninsula, Washington State

    Science.gov (United States)

    Anders, A. M.; Brandon, M. T.

    2008-12-01

    Available data indicate that large and persistent precipitation gradients are tied to topography at scales down to a few kilometers, but precipitation patterns in the majority of mountain ranges are poorly constrained at scales less than tens of kilometers. A lack of knowledge of precipitation patterns hampers efforts to understand the processes of orographic precipitation and identify the relationships between geomorphic evolution and climate. A new method for mapping precipitation using the stable isotopic composition of surface waters is tested in the Olympic Mountains of Washington State. Measured δD and δ18O of 97 samples of surface water are linearly related and nearly inseparable from the global meteoric water line. A linear orographic precipitation model extended to include in effects of isotopic fractionation via Rayleigh distillation predicts precipitation patterns and isotopic composition of surface water. Seven parameters relating to the climate and isotopic composition of source water are used. A constrained random search identifies the best-fitting parameter set. Confidence intervals for parameter values are defined and precipitation patterns are determined. Average errors for the best-fitting model are 4.8 permil in δD. The difference between the best fitting model and other models within the 95% confidence interval was less than 20%. An independent high-resolution precipitation climatology documents precipitation gradients similar in shape and magnitude to the model derived from surface water isotopic composition. This technique could be extended to other mountain ranges, providing an economical and fast assessment of precipitation patterns requiring minimal field work.

  3. Mapping of Proteomic Composition on the Surfaces of Bacillus spores by Atomic Force Microscopy-based Immunolabeling

    Energy Technology Data Exchange (ETDEWEB)

    Plomp, M; Malkin, A J

    2008-06-02

    Atomic force microscopy provides a unique capability to image high-resolution architecture and structural dynamics of pathogens (e.g. viruses, bacteria and bacterial spores) at near molecular resolution in native conditions. Further development of atomic force microscopy in order to enable the correlation of pathogen protein surface structures with specific gene products is essential to understand the mechanisms of the pathogen life cycle. We have applied an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures through the visualization of the binding of antibodies, conjugated with nanogold particles, to specific epitopes on Bacillus spore surfaces. This information is generated while simultaneously acquiring the surface morphology of the pathogen. The immunospecificity of this labeling method was established through the utilization of specific polyclonal and monoclonal antibodies that target spore coat and exosporium epitopes of Bacillus atrophaeus and Bacillus anthracis spores.

  4. Surface Relief of Mapping

    Science.gov (United States)

    Costa, Manuel F.; Almeida, Jose B.

    1989-02-01

    We will describe in this communication a noncont act method of measuring surface profile, it does not require any surface preparation, and it can be used with a very large range of surfaces from highly reflecting to non reflecting ones and as complex as textile surfaces. This method is reasonably immune to dispersion and diffraction, which usually make very difficult the application of non contact profilometry methods to a wide range of materials and situations, namely on quality control systems in industrial production lines. The method is based on the horizontal shift of the bright spot on a horizontal surface when this is illuminated with an oblique beam and moved vertically. in order to make the profilometry the sample is swept by an oblique light beam and the bright spot position is compared with a reference position. The bright spot must be as small as possible, particularly in very irregular surfaces; so the light beam diameter must be as small as possible and the incidence angle must not be too small. The sensivity of a system based on this method will be given, mostly, by the reception optical system.

  5. Mapping stellar surface features

    International Nuclear Information System (INIS)

    Noah, P.V.

    1987-01-01

    New photometric and spectroscopic observations of the RS Canum Venaticorum binaries Sigma Geminorum and UX Arietis are reported along with details of the Doppler-imaging program SPOTPROF. The observations suggest that the starspot activity on Sigma Gem has decreased to 0.05 magnitude in two years. A photometric spot model for September 1984 to January 1985 found that a single spot covering 2% of the surface and 1000 K cooler than the surrounding photosphere could model the light variations. Equivalent-width observations contemporaneous with the photometric observations did not show any significant variations. Line-profile models from SPOTPROF predict that the variation of the equivalent width of the 6393 A Fe I line should be ∼ 1mA. Photometric observations of UX Ari from January 1984 to March 1985 show an 0.3 magnitude variation indicating a large spot group must cover the surface. Contemporaneous spectroscopic observations show asymmetric line profiles. The Doppler imaging and the photometric light-curve models were used in an iterative method to describe the stellar surface-spot distribution and successfully model both the photometric and the spectroscopic variations

  6. Corrected body surface potential mapping.

    Science.gov (United States)

    Krenzke, Gerhard; Kindt, Carsten; Hetzer, Roland

    2007-02-01

    In the method for body surface potential mapping described here, the influence of thorax shape on measured ECG values is corrected. The distances of the ECG electrodes from the electrical heart midpoint are determined using a special device for ECG recording. These distances are used to correct the ECG values as if they had been measured on the surface of a sphere with a radius of 10 cm with its midpoint localized at the electrical heart midpoint. The equipotential lines of the electrical heart field are represented on the virtual surface of such a sphere. It is demonstrated that the character of a dipole field is better represented if the influence of the thorax shape is reduced. The site of the virtual reference electrode is also important for the dipole character of the representation of the electrical heart field.

  7. Pluto's surface composition and atmosphere

    Science.gov (United States)

    Young, L. A.; Gladstone, R.; Summers, M. E.; Strobel, D. F.; Kammer, J.; Hinson, D. P.; Grundy, W. M.; Cruikshank, D. P.; Protopapa, S.; Schmitt, B.; Stern, A.; Weaver, H. A., Jr.; Olkin, C.; Ennico Smith, K.

    2017-12-01

    New Horizons studied Pluto's N2-dominated neutral atmosphere through radio (at 4.2 cm with the REX radio experiment), solar and stellar occultations and airglow (at 52-187 nm with the Alice ultraviolet spectrograph), and imaging (with the LORRI and MVIC visible-wavelength cameras). It studied the plasma environment and solar wind interaction with in situ instruments (PEPPSI and SWAP). Contemporaneous observations of Pluto's atmosphere from Earth included a ground-based stellar occultation and ALMA observations of gaseous CO and HCN. Joint analysis of these datasets reveal a variable boundary layer; a stable lower atmosphere; radiative heating and cooling; haze production and hydrocarbon chemistry; diffusive equilibrium; and slower-than-expected escape. New Horizons studied Pluto's surface composition with the LEISA near-infrared spectral imager from 1.25 to 2.5 micron. Additional compositional information at higher spatial resolution came from the MVIC 4-channel color imager, which included a channel centered at 0.89 micron specifically designed to detect solid CH4. These instruments allow mapping of the volatiles N2, CO, and CH4, the surface expression of the H2O bedrock, and the dark, reddish material presumed to be tholins. These observations reveal a large equatorial basin (informally named Sptunik Planitia), filled with N2 ice with minor amounts of CO and CH4, surrounded by hills of CH4 and H2O ice. Broadly speaking, composition outside of Sptunik Planitia follows latitudinal banding, with dark, mainly volatile free terrains near the equator, with N2, CO, and CH4 at mid-northern latitudes, and mainly CH4 at high northern latitudes. Deviations from these broad trends are seen, and point to complex surface-atmosphere interactions at diurnal, seasonal, perennial, and million-year timescales.

  8. Sorption Energy Maps of Clay Mineral Surfaces

    International Nuclear Information System (INIS)

    Cygan, Randall T.; Kirkpatrick, R. James

    1999-01-01

    A molecular-level understanding of mineral-water interactions is critical for the evaluation and prediction of the sorption properties of clay minerals that may be used in various chemical and radioactive waste disposal methods. Molecular models of metal sorption incorporate empirical energy force fields, based on molecular orbital calculations and spectroscopic data, that account for Coulombic, van der Waals attractive, and short-range repulsive energies. The summation of the non-bonded energy terms at equally-spaced grid points surrounding a mineral substrate provides a three dimensional potential energy grid. The energy map can be used to determine the optimal sorption sites of metal ions on the exposed surfaces of the mineral. By using this approach, we have evaluated the crystallographic and compositional control of metal sorption on the surfaces of kaolinite and illite. Estimates of the relative sorption energy and most stable sorption sites are derived based on a rigid ion approximation

  9. Integrable mappings via rational elliptic surfaces

    International Nuclear Information System (INIS)

    Tsuda, Teruhisa

    2004-01-01

    We present a geometric description of the QRT map (which is an integrable mapping introduced by Quispel, Roberts and Thompson) in terms of the addition formula of a rational elliptic surface. By this formulation, we classify all the cases when the QRT map is periodic; and show that its period is 2, 3, 4, 5 or 6. A generalization of the QRT map which acts birationally on a pencil of K3 surfaces, or Calabi-Yau manifolds, is also presented

  10. Conformal mapping on Riemann surfaces

    CERN Document Server

    Cohn, Harvey

    2010-01-01

    The subject matter loosely called ""Riemann surface theory"" has been the starting point for the development of topology, functional analysis, modern algebra, and any one of a dozen recent branches of mathematics; it is one of the most valuable bodies of knowledge within mathematics for a student to learn.Professor Cohn's lucid and insightful book presents an ideal coverage of the subject in five pans. Part I is a review of complex analysis analytic behavior, the Riemann sphere, geometric constructions, and presents (as a review) a microcosm of the course. The Riemann manifold is introduced in

  11. Surface Mineralogy Mapping of Ceres from the Dawn Mission

    Science.gov (United States)

    McCord, T. B.; Zambon, F.

    2017-12-01

    Ceres' surface composition is of special interest because it is a window into the interior state and the past evolution of this dwarf planet. Disk-integrated telescopic spectral observations indicated that Ceres' surface is hydroxylated, similar to but not exactly the same as some of the carbonaceous chondrite classes of meteorites. Furthermore, Ceres' bulk density is low, indicating significant water content. The Dawn mission in orbit around Ceres, provided a new and larger set of observations on the mineralogy, molecular and elemental composition, and their distributions in association with surface features and geology. A set of articles was prepared, from which this presentation is derived, that is the first treatment of the entire surface composition of Ceres using the complete High Altitude Mapping Orbit (HAMO) Dawn Ceres data set and the calibrations from all the Dawn instruments. This report provides a current and comprehensive view of Ceres' surface composition and integrates them into general conclusions. Ceres' surface composition shows a fairly uniform distribution of NH4- and Mg-phyllosilicates, carbonates, mixed with a dark component. The widespread presence of phyllosilicates, and salts on Ceres' surface is indicative of the presence of aqueous alteration processes, which involved the whole dwarf planet. There is also likely some contamination by low velocity infall, as seen on Vesta, but it is more difficult to distinguish this infall from native Ceres material, unlike for the Vesta case.

  12. Filtering Color Mapped Textures and Surfaces

    OpenAIRE

    Heitz , Eric; Nowrouzezahrai , Derek; Poulin , Pierre; Neyret , Fabrice

    2013-01-01

    International audience; Color map textures applied directly to surfaces, to geometric microsurface details, or to procedural functions (such as noise), are commonly used to enhance visual detail. Their simplicity and ability to mimic a wide range of realistic appearances have led to their adoption in many rendering problems. As with any textured or geometric detail, proper filtering is needed to reduce aliasing when viewed across a range of distances, but accurate and efficient color map filt...

  13. Complete Surface Mapping of ICF Shells

    International Nuclear Information System (INIS)

    Stephens, R.B.; Olson, D.; Huang, H.; Gibson, J.B.

    2004-01-01

    Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. We have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r(θ, φ) surface map for accurate 3-D modeling of a shot

  14. COMPLETE SURFACE MAPPING OF ICF SHELLS

    International Nuclear Information System (INIS)

    STEPHENS, R.B.; OLSON, D.; HUANG, H.; GIBSON, J.B.

    2003-09-01

    OAK-B135 Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. they have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r(θ,ψ) surface map for accurate 3-D modeling of a shot

  15. Constraints on Europa's Ocean Composition Imposed by Its Surface Composition

    Science.gov (United States)

    Johnson, P. V.; Hodyss, R. P.; Vu, T. H.; Choukroun, M.

    2017-12-01

    Of the non-terrestrial environments within our Solar System, Europa's global liquid water ocean is arguably the most likely to be habitable. As such, understanding the habitability of Europa's ocean is of great interest to astrobiology and is the focus of missions currently being considered for further exploration of Europa. However, direct analysis of the ocean is unlikely in the foreseeable future. As such, our best means of constraining the subsurface ocean composition and its subsequent habitability currently is by further study of Europa's surface chemical composition. Recently, there has been a body of work published that looks at the chemistry of frozen brines representing putative ocean compositions. Here we take a simplified model of a four ionic component (Na, Mg, SO4, Cl) solution and map out what minerals are formed upon freezing as a function of relative ionic concentration, pH, etc. A `flow-chart' of the freezing sequence was developed based on both published and recently acquired experimental results. In performing this exercise, we are able to begin making meaningful links between observations of the surface chemistry and the chemical environment of the internal ocean.

  16. Composite mapping experiences in airborne gamma spectrometry

    International Nuclear Information System (INIS)

    Bucher, B.

    2014-01-01

    During an international intercomparison exercise of airborne gamma spectrometry held in Switzerland 2007 teams from Germany, France and Switzerland were proving their capabilities. One of the tasks was the composite mapping of an area around Basel. Each team was mainly covering the part of its own country at its own flying procedures. They delivered the evaluated data in a data format agreed in advance. The quantities to be delivered were also defined in advance. Nevertheless, during the process to put the data together a few questions raised: Which dose rate was meant? Had the dose rate to be delivered with or without cosmic contribution? Activity per dry or wet mass? Which coordinate system was used? Finally, the data could be put together in one map. For working procedures in case of an emergency, quantities of interest and exchange data format have to be defined in advance. But the procedures have also to be proved regularly. (author)

  17. Spectrally based mapping of riverbed composition

    Science.gov (United States)

    Legleiter, Carl; Stegman, Tobin K.; Overstreet, Brandon T.

    2016-01-01

    Remote sensing methods provide an efficient means of characterizing fluvial systems. This study evaluated the potential to map riverbed composition based on in situ and/or remote measurements of reflectance. Field spectra and substrate photos from the Snake River, Wyoming, USA, were used to identify different sediment facies and degrees of algal development and to quantify their optical characteristics. We hypothesized that accounting for the effects of depth and water column attenuation to isolate the reflectance of the streambed would enhance distinctions among bottom types and facilitate substrate classification. A bottom reflectance retrieval algorithm adapted from coastal research yielded realistic spectra for the 450 to 700 nm range; but bottom reflectance-based substrate classifications, generated using a random forest technique, were no more accurate than classifications derived from above-water field spectra. Additional hypothesis testing indicated that a combination of reflectance magnitude (brightness) and indices of spectral shape provided the most accurate riverbed classifications. Convolving field spectra to the response functions of a multispectral satellite and a hyperspectral imaging system did not reduce classification accuracies, implying that high spectral resolution was not essential. Supervised classifications of algal density produced from hyperspectral data and an inferred bottom reflectance image were not highly accurate, but unsupervised classification of the bottom reflectance image revealed distinct spectrally based clusters, suggesting that such an image could provide additional river information. We attribute the failure of bottom reflectance retrieval to yield more reliable substrate maps to a latent correlation between depth and bottom type. Accounting for the effects of depth might have eliminated a key distinction among substrates and thus reduced discriminatory power. Although further, more systematic study across a broader

  18. Fermi surface mapping: Techniques and visualization

    International Nuclear Information System (INIS)

    Rotenberg, E.; Denlinger, J.D.; Kevan, S.D.

    1997-01-01

    Angle-resolved photoemission (ARP) of valence bands is a mature technique that has achieved spectacular success in band-mapping metals, semiconductors, and insulators. The purpose of the present study was the development of experimental and analytical techniques in ARP which take advantage of third generation light sources. Here the authors studied the relatively simple Cu surface in preparation for other metals. Copper and related metals themselves are of current interest, especially due to its role as an interlayer in spin valves and other magnetic heterostructures. A major goal of this study was the development of a systematic technique to quickly (i.e. in a few hours of synchrotron beamtime) measure the FS and separate it into bulk and surface FS's. Often, one needs to avoid bulk features altogether, which one can achieve by carefully mapping their locations in k-space. The authors will also show how they systematically map Fermi surfaces throughout large volumes of k-space, and, by processing the resulting volume data sets, provide intuitive pictures of FS's, both bulk and surface

  19. Composite mapping experiences in airborne gamma spectrometry.

    Science.gov (United States)

    Bucher, B

    2014-08-01

    During an international intercomparison exercise of airborne gamma spectrometry held in Switzerland 2007 teams from Germany, France and Switzerland were proving their capabilities. One of the tasks was the composite mapping of an area around Basel. Each team was mainly covering the part of its own country at its own flying procedures. They delivered the evaluated data in a data format agreed in advance. The quantities to be delivered were also defined in advance. Nevertheless, during the process to put the data together a few questions raised: Which dose rate was meant? Had the dose rate to be delivered with or without cosmic contribution? Activity per dry or wet mass? Which coordinate system was used? Finally, the data could be put together in one map. For working procedures in case of an emergency, quantities of interest and exchange data format have to be defined in advance. But the procedures have also to be proved regularly. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Highly accurate surface maps from profilometer measurements

    Science.gov (United States)

    Medicus, Kate M.; Nelson, Jessica D.; Mandina, Mike P.

    2013-04-01

    Many aspheres and free-form optical surfaces are measured using a single line trace profilometer which is limiting because accurate 3D corrections are not possible with the single trace. We show a method to produce an accurate fully 2.5D surface height map when measuring a surface with a profilometer using only 6 traces and without expensive hardware. The 6 traces are taken at varying angular positions of the lens, rotating the part between each trace. The output height map contains low form error only, the first 36 Zernikes. The accuracy of the height map is ±10% of the actual Zernike values and within ±3% of the actual peak to valley number. The calculated Zernike values are affected by errors in the angular positioning, by the centering of the lens, and to a small effect, choices made in the processing algorithm. We have found that the angular positioning of the part should be better than 1?, which is achievable with typical hardware. The centering of the lens is essential to achieving accurate measurements. The part must be centered to within 0.5% of the diameter to achieve accurate results. This value is achievable with care, with an indicator, but the part must be edged to a clean diameter.

  1. Mapping the global land surface using 1 km AVHRR data

    Science.gov (United States)

    Lauer, D.T.; Eidenshink, J.C.

    1998-01-01

    The scientific requirements for mapping the global land surface using 1 km advanced very high resolution radiometer (AVHRR) data have been set forth by the U.S. Global Change Research Program; the International Geosphere Biosphere Programme (IGBP); The United Nations; the National Oceanic and Atmospheric Administration (NOAA); the Committee on Earth Observations Satellites; and the National Aeronautics and Space Administration (NASA) mission to planet Earth (MTPE) program. Mapping the global land surface using 1 km AVHRR data is an international effort to acquire, archive, process, and distribute 1 km AVHRR data to meet the needs of the international science community. A network of AVHRR receiving stations, along with data recorded by NOAA, has been acquiring daily global land coverage since April 1, 1992. A data set of over 70,000 AVHRR images is archived and distributed by the United States Geological Survey (USGS) EROS Data Center, and the European Space Agency. Under the guidance of the IGBP, processing standards have been developed for calibration, atmospheric correction, geometric registration, and the production of global 10-day maximum normalized difference vegetation index (NDVI) composites. The major uses of the composites are for the study of surface vegetation condition, mapping land cover, and deriving biophysical characteristics of terrestrial ecosystems. A time-series of 54 10-day global vegetation index composites for the period of April 1, 1992 through September 1993 has been produced. The production of a time-series of 33 10-day global vegetation index composites using NOAA-14 data for the period of February 1, 1995 through December 31, 1995 is underway. The data products are available from the USGS, in cooperation with NASA's MTPE program and other international organizations.

  2. Compositions of nuclear maps with vector measures and ...

    African Journals Online (AJOL)

    The properties of the compositions of nuclear maps, between two locally convex spaces, with vector measures and measurable functions are investigated. The composition with a vector measure has improved variational properties and a precompact range. The measurability and integrability properties of the composition of ...

  3. Geomorphic Surface Maps of Northern Frenchman Flat, Nevada Test Site, Southern Nevada

    International Nuclear Information System (INIS)

    Bechtel Nevada

    2005-01-01

    Large-scale (1:6000) surficial geology maps of northern Frenchman Flat were developed in 1995 as part of comprehensive site characterization required to operate a low-level radioactive waste disposal facility in that area. Seven surficial geology maps provide fundamental data on natural processes and are the platform needed to reconstruct the Quaternary history of northern Frenchman Flat. Reconstruction of the Quaternary history provides an understanding of the natural processes that act to develop the landscape, and the time-frames involved in landscape development. The mapping was conducted using color and color-infrared aerial photographs and field verification of map unit composition and boundaries. Criteria for defining the map unit composition of geomorphic surface units are based on relative geomorphic position, landform morphology, and degree of preservation of surface morphology. Seven geomorphic surfaces (Units 1 through 7) are recognized, spanning from the early Quaternary to present time

  4. Preliminary Correlation Map of Geomorphic Surfaces in North-Central Frenchman Flat, Nevada Test Site

    International Nuclear Information System (INIS)

    Bechtel Nevada

    2005-01-01

    This correlation map (scale = 1:12,000) presents the results of a mapping initiative that was part of the comprehensive site characterization required to operate the Area 5 Radioactive Waste Management Site, a low-level radioactive waste disposal facility located in northern Frenchman Flat at the Nevada Test Site. Eight primary map units are recognized for Quaternary surfaces: remnants of six alluvial fan or terrace surfaces, one unit that includes colluvial aprons associated with hill slopes, and one unit for anthropogenically disturbed surfaces. This surficial geology map provides fundamental data on natural processes for reconstruction of the Quaternary history of northern Frenchman Flat, which in turn will aid in the understanding of the natural processes that act to develop the landscape, and the time-frames involved in landscape development. The mapping was conducted using color and color-infrared aerial photographs and field verification of map unit composition and boundaries. Criteria for defining the map unit composition of geomorphic surface units are based on relative geomorphic position, landform morphology, and degree of preservation of surface morphology. The bedrock units identified on this map were derived from previous published mapping efforts and are included for completeness

  5. Mapping QTL for fatty acid composition that segregates between the ...

    African Journals Online (AJOL)

    Mapping QTL for fatty acid composition that segregates between the Japanese Black and Limousin cattle breeds (Short communication). NOM Tshipuliso, LJ Alexander, TW Geary, VM Snelling, DC Rule, JE Koltes, BE Mote, MD MacNeil ...

  6. Surface composition and surface properties of water hyacinth ...

    African Journals Online (AJOL)

    Surface composition and surface properties of water hyacinth ( Eichhornia ... (2/1, v/v) followed by ethanol, using Fourier Transform Infra-red (FT-IR) spectroscopy, ... polar organic solvents and non-polar n-alkane hydrocarbons is discussed.

  7. Visualizing Composite Data on the Lexis Surface

    DEFF Research Database (Denmark)

    Schöley, Jonas; Willekens, Frans

    The analysis of composite data is a topic inherent to demography. In recent times, due to a growing catalogue of detailed population data, it became feasible to consider populations not only structured by time, age or sex, but by any number of interesting criteria. This “inflation” of data...... dimensions produces challenges in visualizing the data. To aid the understanding of age-structured timelines of compositions we seek to extend the Lexis surface plot from 1-dimensional continuous data to multidimensional composite data. We apply different strategies for visualizing composite data...

  8. LSM Microelectrodes: Kinetics and Surface Composition

    DEFF Research Database (Denmark)

    Hansen, Karin Vels; Norrman, Kion; Jacobsen, Torben

    2015-01-01

    spectroscopy and cyclic voltammetry were performed on electrodes with diameters of 20–100 μm in oxygen, air and nitrogen both at open circuit voltage and at anodic and cathodic polarization. In situ conductance mapping, ex situ surface analysis by time-of-flight secondary ion mass spectrometry, and scanning...

  9. Reproducibility of crop surface maps extracted from Unmanned Aerial Vehicle (UAV) derived digital surface maps

    KAUST Repository

    Parkes, Stephen

    2016-10-25

    Crop height measured from UAVs fitted with commercially available RGB cameras provide an affordable alternative to retrieve field scale high resolution estimates. The study presents an assessment of between flight reproducibility of Crop Surface Maps (CSM) extracted from Digital Surface Maps (DSM) generated by Structure from Motion (SfM) algorithms. Flights were conducted over a centre pivot irrigation system covered with an alfalfa crop. An important step in calculating the absolute crop height from the UAV derived DSM is determining the height of the underlying terrain. Here we use automatic thresholding techniques applied to RGB vegetation index maps to classify vegetated and soil pixels. From interpolation of classified soil pixels, a terrain map is calculated and subtracted from the DSM. The influence of three different thresholding techniques on CSMs are investigated. Median Alfalfa crop heights determined with the different thresholding methods varied from 18cm for K means thresholding to 13cm for Otsu thresholding methods. Otsu thresholding also gave the smallest range of crop heights and K means thresholding the largest. Reproducibility of median crop heights between flight surveys was 4-6cm for all thresholding techniques. For the flight conducted later in the afternoon shadowing caused soil pixels to be classified as vegetation in key locations around the domain, leading to lower crop height estimates. The range of crop heights was similar for both flights using K means thresholding (35-36cm), local minimum thresholding depended on whether raw or normalised RGB intensities were used to calculate vegetation indices (30-35cm), while Otsu thresholding had a smaller range of heights and varied most between flights (26-30cm). This study showed that crop heights from multiple survey flights are comparable, however, they were dependent on the thresholding method applied to classify soil pixels and the time of day the flight was conducted.

  10. Reproducibility of crop surface maps extracted from Unmanned Aerial Vehicle (UAV) derived digital surface maps

    KAUST Repository

    Parkes, Stephen; McCabe, Matthew; Al-Mashhawari, Samir K.; Rosas, Jorge

    2016-01-01

    Crop height measured from UAVs fitted with commercially available RGB cameras provide an affordable alternative to retrieve field scale high resolution estimates. The study presents an assessment of between flight reproducibility of Crop Surface Maps (CSM) extracted from Digital Surface Maps (DSM) generated by Structure from Motion (SfM) algorithms. Flights were conducted over a centre pivot irrigation system covered with an alfalfa crop. An important step in calculating the absolute crop height from the UAV derived DSM is determining the height of the underlying terrain. Here we use automatic thresholding techniques applied to RGB vegetation index maps to classify vegetated and soil pixels. From interpolation of classified soil pixels, a terrain map is calculated and subtracted from the DSM. The influence of three different thresholding techniques on CSMs are investigated. Median Alfalfa crop heights determined with the different thresholding methods varied from 18cm for K means thresholding to 13cm for Otsu thresholding methods. Otsu thresholding also gave the smallest range of crop heights and K means thresholding the largest. Reproducibility of median crop heights between flight surveys was 4-6cm for all thresholding techniques. For the flight conducted later in the afternoon shadowing caused soil pixels to be classified as vegetation in key locations around the domain, leading to lower crop height estimates. The range of crop heights was similar for both flights using K means thresholding (35-36cm), local minimum thresholding depended on whether raw or normalised RGB intensities were used to calculate vegetation indices (30-35cm), while Otsu thresholding had a smaller range of heights and varied most between flights (26-30cm). This study showed that crop heights from multiple survey flights are comparable, however, they were dependent on the thresholding method applied to classify soil pixels and the time of day the flight was conducted.

  11. Visualizing compositional data on the Lexis surface

    DEFF Research Database (Denmark)

    Schöley, Jonas; Willekens, Frans

    2017-01-01

    the visualizations for compliance with multiple desired criteria. Results: Compositional data can effectively be visualized on the Lexis surface. A key feature of the classical Lexis surface plot – to show age, period, and cohort patterns – is retained in the domain of compositions. The optimal choice among the four...... and demonstrate the usefulness of the techniques by performing an exploratory analysis of age-specific French cause-of-death patterns across the 20th century. We identify strengths and weaknesses of the four proposed techniques. We contribute a technique to construct the ternary-balance colour scheme from within...

  12. Visualizing compositional data on the Lexis surface

    Directory of Open Access Journals (Sweden)

    Jonas Schöley

    2017-02-01

    Full Text Available Background: The Lexis surface plot is an established visualization tool in demography. Its presentutility, however, is limited to the domain of one-dimensional magnitudes such as ratesand counts. Visualizing proportions among three or more groups on a period-age grid isan unsolved problem. Objective: We seek to extend the Lexis surface plot to the domain of compositional data. Methods: We propose four techniques for visualizing group compositions on a period-age grid. Todemonstrate the techniques we use data on age-specific cause-of-death compositions inFrance from 1925 to 1999. We compare the visualizations for compliance with multipledesired criteria. Results: Compositional data can effectively be visualized on the Lexis surface. A key feature ofthe classical Lexis surface plot - to show age, period, and cohort patterns - is retainedin the domain of compositions. The optimal choice among the four proposed techniquesdepends primarily on the number of groups making up the composition and whether ornot the plot should be readable by people with impaired colour vision. Contribution: We introduce techniques for visualizing compositional data on a period-age grid to thefield of demography and demonstrate the usefulness of the techniques by performingan exploratory analysis of age-specific French cause-of-death patterns across the 20thcentury. We identify strengths and weaknesses of the four proposed techniques. We contribute a technique to construct the ternary-balance colour scheme from within a per-ceptually uniform colour space. Comments: A full-colour representation is key to understanding the paper. Therefore, we recommend that you read it on screen or print a colour version.

  13. Surface composition of Mercury from reflectance spectrophotometry

    Science.gov (United States)

    Vilas, Faith

    1988-01-01

    The controversies surrounding the existing spectra of Mercury are discussed together with the various implications for interpretations of Mercury's surface composition. Special attention is given to the basic procedure used for reducing reflectance spectrophotometry data, the factors that must be accounted for in the reduction of these data, and the methodology for defining the portion of the surface contributing the greatest amount of light to an individual spectrum. The application of these methodologies to Mercury's spectra is presented.

  14. Titan's Surface Composition from Cassini VIMS Solar Occultation Observations

    Science.gov (United States)

    McCord, Thomas; Hayne, Paul; Sotin, Christophe

    2013-04-01

    Titan's surface is obscured by a thick absorbing and scattering atmosphere, allowing direct observation of the surface within only a few spectral win-dows in the near-infrared, complicating efforts to identify and map geologi-cally important materials using remote sensing IR spectroscopy. We there-fore investigate the atmosphere's infrared transmission with direct measure-ments using Titan's occultation of the Sun as well as Titan's reflectance measured at differing illumination and observation angles observed by Cas-sini's Visual and Infrared Mapping Spectrometer (VIMS). We use two im-portant spectral windows: the 2.7-2.8-mm "double window" and the broad 5-mm window. By estimating atmospheric attenuation within these windows, we seek an empirical correction factor that can be applied to VIMS meas-urements to estimate the true surface reflectance and map inferred composi-tional variations. Applying the empirical corrections, we correct the VIMS data for the viewing geometry-dependent atmospheric effects to derive the 5-µm reflectance and 2.8/2.7-µm reflectance ratio. We then compare the cor-rected reflectances to compounds proposed to exist on Titan's surface. We propose a simple correction to VIMS Titan data to account for atmospheric attenuation and diffuse scattering in the 5-mm and 2.7-2.8 mm windows, generally applicable for airmass water ice for the majority of the low-to-mid latitude area covered by VIMS measurements. Four compositional units are defined and mapped on Titan's surface based on the positions of data clusters in 5-mm vs. 2.8/2.7-mm scatter plots; a simple ternary mixture of H2O, hydrocarbons and CO2 might explain the reflectance properties of these surface units. The vast equatorial "dune seas" are compositionally very homogeneous, perhaps suggesting transport and mixing of particles over very large distances and/or and very consistent formation process and source material. The composi-tional branch characterizing Tui Regio and Hotei Regio is

  15. The Origin of Mercury's Surface Composition, an Experimental Investigation

    Science.gov (United States)

    Boujibar, A.; Righter, K.; Rapp, J. F.; Ross, D. K.; Pando, K. M.; Danielson, L. R.; Fontaine, E.

    2016-01-01

    Introduction: Results from MESSENGER spacecraft have confirmed the reduced nature of Mercury, based on its high core/mantle ratio and its FeO-poor and S-rich surface. Moreover, high resolution images revealed large volcanic plains and abundant pyroclastic deposits, suggesting major melting stages of the Mercurian mantle. In addition, MESSENGER has provided the most precise data to date on major elemental compositions of Mercury's surface. These results revealed considerable chemical heterogeneities that suggested several stages of differentiation and re-melting processes. This interpretation was challenged by our experimental previous study, which showed a similar compositional variation in the melting products of enstatite chondrites, which are a possible Mercury analogue. However, these experimental melts were obtained over a limited range of pressure (1 bar to 1 gigapascal) and were not compared to the most recent elemental maps. Therefore, here we extend the experimental dataset to higher pressures and perform a more quantitative comparison with Mercury's surface compositions measured by MESSENGER. In particular, we test whether these chemical heterogeneities result from mixing between polybaric melts. Our experiments and models show that the majority of chemical diversity of Mercury's surface can result from melting of a primitive mantle compositionally similar to enstatite chondrites in composition at various depths and degrees of melting. The high-Mg region's composition is reproduced by melting at high pressure (3 gigapascals) (Tab. 1), which is consistent with previous interpretation as being a large degraded impact basin based on its low elevation and thin average crust. While low-Mg NVP (North Volcanic Plains) are the result of melting at low pressure (1 bar), intermediate-Mg NVP, Caloris Basin and Rachmaninoff result from mixing of a high-pressure (3 gigapascals) and low-pressure components (1 bar for Rachmaninoff and 1 gigapascal for the other regions

  16. 3D silicon breast surface mapping via structured light profilometry

    Science.gov (United States)

    Vairavan, R.; Ong, N. R.; Sauli, Z.; Kirtsaeng, S.; Sakuntasathien, S.; Shahimin, M. M.; Alcain, J. B.; Lai, S. L.; Paitong, P.; Retnasamy, V.

    2017-09-01

    Digital fringe projection technique is one of the promising optical methods for 3D surface imaging as it demonstrates non contact and non invasive characteristics. The potential of this technique matches the requirement for human body evaluation, as it is vital for disease diagnosis and for treatment option selection. Thus, the digital fringe projection has addressed this requirement with its wide clinical related application and studies. However, the application of this technique for 3D surface mapping of the breast is very minimal. Hence, in this work, the application of digital fringe projection for 3D breast surface mapping is reported. Phase shift fringe projection technique was utilized to perform the 3D breast surface mapping. Maiden results have confirmed the feasibility of using the digital fringe projection method for 3D surface mapping of the breast and it can be extended for breast cancer detection.

  17. Molecular surface mesh generation by filtering electron density map.

    Science.gov (United States)

    Giard, Joachim; Macq, Benoît

    2010-01-01

    Bioinformatics applied to macromolecules are now widely spread and in continuous expansion. In this context, representing external molecular surface such as the Van der Waals Surface or the Solvent Excluded Surface can be useful for several applications. We propose a fast and parameterizable algorithm giving good visual quality meshes representing molecular surfaces. It is obtained by isosurfacing a filtered electron density map. The density map is the result of the maximum of Gaussian functions placed around atom centers. This map is filtered by an ideal low-pass filter applied on the Fourier Transform of the density map. Applying the marching cubes algorithm on the inverse transform provides a mesh representation of the molecular surface.

  18. Molecular Surface Mesh Generation by Filtering Electron Density Map

    Directory of Open Access Journals (Sweden)

    Joachim Giard

    2010-01-01

    Full Text Available Bioinformatics applied to macromolecules are now widely spread and in continuous expansion. In this context, representing external molecular surface such as the Van der Waals Surface or the Solvent Excluded Surface can be useful for several applications. We propose a fast and parameterizable algorithm giving good visual quality meshes representing molecular surfaces. It is obtained by isosurfacing a filtered electron density map. The density map is the result of the maximum of Gaussian functions placed around atom centers. This map is filtered by an ideal low-pass filter applied on the Fourier Transform of the density map. Applying the marching cubes algorithm on the inverse transform provides a mesh representation of the molecular surface.

  19. Composition and physical properties of Enceladus' surface

    Science.gov (United States)

    Brown, R.H.; Clark, R.N.; Buratti, B.J.; Cruikshank, D.P.; Barnes, J.W.; Mastrapa, R.M.E.; Bauer, J.; Newman, S.; Momary, T.; Baines, K.H.; Bellucci, G.; Capaccioni, F.; Cerroni, P.; Combes, M.; Coradini, A.; Drossart, P.; Formisano, V.; Jaumann, R.; Langavin, Y.; Matson, D.L.; McCord, T.B.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, Christophe

    2006-01-01

    Observations of Saturn's satellite Enceladus using Cassini's Visual and Infrared Mapping Spectrometer instrument were obtained during three flybys of Enceladus in 2005. Enceladus' surface is composed mostly of nearly pure water ice except near its south pole, where there are light organics, CO2, and amorphous and crystalline water ice, particularly in the region dubbed the "tiger stripes." An upper limit of 5 precipitable nanometers is derived for CO in the atmospheric column above Enceladus, and 2% for NH 3 in global surface deposits. Upper limits of 140 kelvin (for a filled pixel) are derived for the temperatures in the tiger stripes.

  20. Air transport pilots' information priorities for surface moving maps

    Science.gov (United States)

    2003-10-13

    The use of a surface map display for operations on or near the airport surface (taxi out, takeoff, final approach and landing, taxi in) is expected to enhance safety. There is a lack of research, however, detailing how the airport surface should be d...

  1. Surface Preparation for Microdebonding Analysis of Composites

    International Nuclear Information System (INIS)

    Kahraman, Ramazan; Mandell, J. F.

    1999-01-01

    The bond strength between fibers and matrix is an essential property of all composite materials and it must be measured accurately to be able to correlate it with the composite behavior. There are several factors affecting its measurement. This paper discusses the polishing and load application aspects of the indentation test technique for fibre-matrix bond strength determination in polymer and ceramic matrix composites. Different polishing procedures are suggested for polymer and ceramic surfaces for obtaining a smooth surface which is a must for the test results to be reliable. The geometry of the fibers tested was also found to affect the analysis results. For best results, fibers with similar size and which are similarly surrounded by other fibers should be tested. Care should be taken during load application on a fiber for the loading probe not to approach the fiber circumference. The force should be applied in a small increments as possible, however starting from a high enough level to prevent fiber breakage due to surface damage from several loading steps. (Author)

  2. Pseudo-periodic maps and degeneration of Riemann surfaces

    CERN Document Server

    Matsumoto, Yukio

    2011-01-01

    The first part of the book studies pseudo-periodic maps of a closed surface of genus greater than or equal to two. This class of homeomorphisms was originally introduced by J. Nielsen in 1944 as an extension of periodic maps. In this book, the conjugacy classes of the (chiral) pseudo-periodic mapping classes are completely classified, and Nielsen’s incomplete classification is corrected. The second part applies the results of the first part to the topology of degeneration of Riemann surfaces. It is shown that the set of topological types of all the singular fibers appearing in one-parameter holomorphic families of Riemann surfaces is in a bijective correspondence with the set of conjugacy classes of the pseudo-periodic maps of negative twists. The correspondence is given by the topological monodromy.

  3. (90377) SEDNA: INVESTIGATION OF SURFACE COMPOSITIONAL VARIATION

    International Nuclear Information System (INIS)

    Barucci, M. A.; De Bergh, C.; Merlin, F.; Morea Dalle Ore, C.; Cruikshank, D.; Alvarez-Candal, A.; Dumas, C.

    2010-01-01

    The dwarf planet (90377) Sedna is one of the most remote solar system objects accessible to investigations. To better constrain its surface composition and to investigate the possible heterogeneity of the surface of Sedna, several observations have been carried out at ESO-VLT with the powerful spectrometer SINFONI observing simultaneously the H and K bands. The analyzed spectra (obtained in 2005, 2007, and 2008) show a non-uniform spectral signature, particularly in the K band. Spectral modeling using the Shkuratov radiative transfer code for surface scattering has been performed using the various sets of data, including previous observations at visible wavelengths and photometry at 3.6 and 4.5 μm by the Spitzer Space Telescope. The visible and near-infrared spectra can be modeled with organic materials (triton and titan tholin), serpentine, and H 2 O ice in fairly significant amounts, and CH 4 , N 2 , and C 2 H 6 in varying trace amounts. One of the spectra obtained in 2005 October shows a different signature in the K band and is best modeled with CH 3 OH in place of CH 4 , with reduced amounts of serpentine and with the addition of olivine. The compositional surface heterogeneity can give input on the past history as well clues to the origin of this peculiar, distant object.

  4. Ray-map migration of transmitted surface waves

    KAUST Repository

    Li, Jing

    2016-08-25

    Near-surface normal faults can sometimes separate two distinct zones of velocity heterogeneity, where the medium on one side of the fault has a faster velocity than on the other side. Therefore, the slope of surface-wave arrivals in a common-shot gather should abruptly change near the surface projection of the fault. We present ray-map imaging method that migrates transmitted surface waves to the fault plane, and therefore it roughly estimates the orientation, depth, and location of the near-surface fault. The main benefits of this method are that it is computationally inexpensive and robust in the presence of noise.

  5. Producing of multicomponent and composite surface layers

    International Nuclear Information System (INIS)

    Wierzchon, T.; Bielinski, P.; Michalski, A.

    1995-01-01

    The paper presents a new method of producing multicomponent and composite layers on steel substrate. The combination of nickel plating with glow-discharge bordering or impulse-plasma deposition method gives an opportunity to obtain good properties of surface layers. The results of examinations of carbon 45 (0.45%C) steel, nickel plated and then borided under glow discharge conditions or covered with TiN layers are presented. The corrosion and friction wear resistance of such layers are markedly higher than for layer produced on non nickel plated substrates. (author). 19 refs, 5 figs

  6. Surface mineral maps of Afghanistan derived from HyMap imaging spectrometer data, version 2

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.

    2013-01-01

    This report presents a new version of surface mineral maps derived from HyMap imaging spectrometer data collected over Afghanistan in the fall of 2007. This report also describes the processing steps applied to the imaging spectrometer data. The 218 individual flight lines composing the Afghanistan dataset, covering more than 438,000 square kilometers, were georeferenced to a mosaic of orthorectified Landsat images. The HyMap data were converted from radiance to reflectance using a radiative transfer program in combination with ground-calibration sites and a network of cross-cutting calibration flight lines. The U.S. Geological Survey Material Identification and Characterization Algorithm (MICA) was used to generate two thematic maps of surface minerals: a map of iron-bearing minerals and other materials, which have their primary absorption features at the shorter wavelengths of the reflected solar wavelength range, and a map of carbonates, phyllosilicates, sulfates, altered minerals, and other materials, which have their primary absorption features at the longer wavelengths of the reflected solar wavelength range. In contrast to the original version, version 2 of these maps is provided at full resolution of 23-meter pixel size. The thematic maps, MICA summary images, and the material fit and depth images are distributed in digital files linked to this report, in a format readable by remote sensing software and Geographic Information Systems (GIS). The digital files can be downloaded from http://pubs.usgs.gov/ds/787/downloads/.

  7. Orientation Mapping of Extruded Polymeric Composites by Polarized Micro-Raman Spectroscopy

    Directory of Open Access Journals (Sweden)

    Xiaoyun Chen

    2015-01-01

    Full Text Available Molecular orientation has a strong influence on polymeric composite materials’ mechanical properties. In this paper we describe the use of polarized micro-Raman spectroscopy as a powerful tool to map out the molecular orientation of a uniaxially oriented polypropylene- (PP- based composite material. Initial samples exhibited a high degree of surface fibrillation upon cutting. Raman spectroscopy was used to characterize the degree of orientation in the skin and guide the development of the posttreatment process to optimize the skin relaxation while maintaining the high degree of orientation in the rest of the board. The PP oriented polymer composite (OPC was oriented through an extrusion process and its surface was then treated to achieve relaxation. Micro-Raman analysis at the surface region demonstrated the surface orientation relaxation, and the results provide an effective way to correlate the extent of relaxation and process conditions. Larger scale orientation mapping was also carried out over the entire cross-section (12.7 cm × 2.54 cm. The results agree well with prior expectation of the molecular orientation based on the extrusion and subsequent quenching process. The methodologies described here can be readily applied to other polymeric systems.

  8. Multi-Beam Surface Lidar for Lunar and Planetary Mapping

    Science.gov (United States)

    Bufton, Jack L.; Garvin, James B.

    1998-01-01

    Surface lidar techniques are now being demonstrated in low Earth orbit with a single beam of pulsed laser radiation at 1064 nm that profiles the vertical structure of Earth surface landforms along the nadir track of a spacecraft. In addition, a profiling laser altimeter, called MOLA, is operating in elliptical Martian orbit and returning surface topography data. These instruments form the basis for suggesting an improved lidar instrument that employs multiple beams for extension of sensor capabilities toward the goal of true, 3-dimensional mapping of the Moon or other similar planetary surfaces. In general the lidar waveform acquired with digitization of a laser echo can be used for laser distance measurement (i.e. range-to-the-surface) by time-of-flight measurement and for surface slope and shape measurements by examining the detailed lidar waveform. This is particularly effective when the intended target is the lunar surface or another planetary body free of any atmosphere. The width of the distorted return pulse is a first order measure of the surface incidence angle, a combination of surface slope and laser beam pointing. Assuming an independent and absolute (with respect to inertial space) measurement of laser beam pointing on the spacecraft, it is possible to derive a surface slope with-respect-to the mean planetary surface or its equipotential gravity surface. Higher-order laser pulse distortions can be interpreted in terms of the vertical relief of the surface or reflectivity variations within the area of the laser beam footprint on the surface.

  9. Modelling and Mapping Oxygen-18 Isotope Composition of Precipitation in Spain for Hydrologic and Climatic Applications

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Arevalo, J.; Diaz-Teijeiro, M. F. [Centro de Estudios y Experimentacion de Obras Publicas (CEDEX), Madrid (Spain); Castano, S. [Geological Survey of Spain (IGME), Madrid (Spain)

    2013-07-15

    A simple multiple regression model based on two geographic factors (latitude and elevation) has been developed that reproduces reasonably well the spatial distribution of the current mean oxygen-18 isotope composition in precipitation over spain. In a preliminary analysis, additional geographic and climatic factors do not improve the performance of the model. A continuous digital map of oxygen-18 isotope composition in precipitation has been produced by combining the polynomial model with a digital elevation model using GIS tools. Application of the resulting map to several groundwater case studies in spain has shown it to be useful as a reference of the input function to recharge. Further validation of the model, and further testing of its usefulness in surface hydrology and climatic studies, is ongoing through comparison of model results with isotope data from the GNIP database and from isotope studies in hydrogeology and climate change taking place in spain. (author)

  10. Sea surface temperature mapping using a thermal infrared scanner

    Digital Repository Service at National Institute of Oceanography (India)

    RameshKumar, M.R; Pandya, R; Mathur, K.M.; Charyulu, R; Rao, L.V.G.

    1 metre water column below the sea surface. A thermal infrared scanner developed by the Space Applications Centre (ISRO), Ahmedabad was operated on board R.V. Gaveshani in April/May 1984 for mapping SST over the eastern Arabian Sea. SST values...

  11. Groupoid extensions of mapping class representations for bordered surfaces

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Bene, Alex; Penner, Robert

    2009-01-01

    by explicit formulae depending upon six essential cases, and the kernel and image of the groupoid representation are computed. Furthermore, this provides groupoid extensions of any representation of the mapping class group that factors through its action on the fundamental group of the surface including...

  12. Use of roughness maps in visualisation of surfaces

    DEFF Research Database (Denmark)

    Seitavuopio, Paulus; Rantanen, Jukka; Yliruusi, Jouko

    2005-01-01

    monohydrate, theophylline anhydrate, sodium chloride and potassium chloride. The roughness determinations were made by a laser profilometer. The new matrix method gives detailed roughness maps, which are able to show local variations in surface roughness values and provide an illustrative picture...

  13. Surface composition of Europa based on VLT observations

    Science.gov (United States)

    Ligier, N.; Poulet, F.; Carter, J.

    2016-12-01

    Jupiter's moon Europa may harbor a global salty ocean under an 80-170 km thick outer layer consisting of an icy crust (Anderson et al. 1998). Meanwhile, the 10-50 My old surface, dated by cratering rates (Pappalardo et al. 1999) implies rapid surface recycling and reprocessing that could result in tectonic activity (Kattenhorn et al. 2014) and plumes (Roth et al. 2014). The surface could thus exhibit fingerprints of chemical species, as minerals characteristics of an ocean-mantle interaction and/or organics of exobiological interest, directly originating from the subglacial ocean. In order to re-investigate the composition of Europa's surface, a global mapping campaign of the satellite was performed with the near-infrared integral field spectrograph SINFONI on the Very Large Telescope (VLT) in Chile. The high spectral binning of this instrument (0.5 nm) and large signal noise ratio in comparison to previous observations are adequate to detect sharp absorptions in the wavelength range 1.45-2.45 μm. In addition, the spatially resolved spectra we obtained over five epochs nearly cover the entire surface of Europa with a pixel scale of 12.5 by 25 m.a.s ( 35 by 70 km on Europa's surface), thus permitting a global scale study. Several icy and non-icy compounds were detected and mapped at <100 km resolution. They are unevenly distributed on the moon's surface. Amorphous and crystalline water ice are both present and, in spite of a particularly strong amorphization process likely engendered by the Io plasma torus, the crystalline form is found to be approximately twice as abundant as the amorphous ice based on the analysis of the 1.65 μm band. If the surface is dominated by small and mid-sized water ice grains (25-200 μm), crystalline water-ice grains exhibit spatial inhomogeneities in their distribution. The sulfuric acid hydrate distribution exhibits the typical "bullseye" feature on the trailing hemisphere. The presence of Mg-bearing chlorinated salts (chloride

  14. Crystal orientation mapping applied to the Y-TZP/WC composite

    CERN Document Server

    Faryna, M; Sztwiertnia, K

    2002-01-01

    Crystal orientation measurements made by electron backscattered diffraction (EBSD) in the scanning electron microscope (SEM) and microscopic observations provided the basis for a quantitative investigation of microstructure in an yttria stabilized, tetragonal zirconia-based (Y-TZP) composite. Automatic crystal orientation mapping (ACOM) in a SEM can be preferable to transmission electron microscopy (TEM) for microstructural characterization, since no sample thinning is required, extensive crystal data is already available, and the analysis area is greatly increased. A composite with a 20 vol.% tungsten carbide (WC) content was chosen since it revealed crystal relationships between the matrix and carbide phase already established by TEM analysis. However, this composite was difficult to investigate in the EBSD/ SEM since it is non-conductive, the Y-TZP grain size is of the order of the system resolution, and the sample surface, though carefully prepared, reveals a distinctive microtopography. In this paper, so...

  15. Venus Surface Composition Constrained by Observation and Experiment

    Science.gov (United States)

    Gilmore, Martha; Treiman, Allan; Helbert, Jörn; Smrekar, Suzanne

    2017-11-01

    New observations from the Venus Express spacecraft as well as theoretical and experimental investigation of Venus analogue materials have advanced our understanding of the petrology of Venus melts and the mineralogy of rocks on the surface. The VIRTIS instrument aboard Venus Express provided a map of the southern hemisphere of Venus at ˜1 μm allowing, for the first time, the definition of surface units in terms of their 1 μm emissivity and derived mineralogy. Tessera terrain has lower emissivity than the presumably basaltic plains, consistent with a more silica-rich or felsic mineralogy. Thermodynamic modeling and experimental production of melts with Venera and Vega starting compositions predict derivative melts that range from mafic to felsic. Large volumes of felsic melts require water and may link the formation of tesserae to the presence of a Venus ocean. Low emissivity rocks may also be produced by atmosphere-surface weathering reactions unlike those seen presently. High 1 μm emissivity values correlate to stratigraphically recent flows and have been used with theoretical and experimental predictions of basalt weathering to identify regions of recent volcanism. The timescale of this volcanism is currently constrained by the weathering of magnetite (higher emissivity) in fresh basalts to hematite (lower emissivity) in Venus' oxidizing environment. Recent volcanism is corroborated by transient thermal anomalies identified by the VMC instrument aboard Venus Express. The interpretation of all emissivity data depends critically on understanding the composition of surface materials, kinetics of rock weathering and their measurement under Venus conditions. Extended theoretical studies, continued analysis of earlier spacecraft results, new atmospheric data, and measurements of mineral stability under Venus conditions have improved our understanding atmosphere-surface interactions. The calcite-wollastonite CO2 buffer has been discounted due, among other things, to

  16. Far-UV Spectral Mapping of Lunar Composition, Porosity, and Space Weathering: LRO Lyman Alpha Mapping Project (LAMP)

    Science.gov (United States)

    Retherford, K. D.; Greathouse, T. K.; Mandt, K.; Gladstone, R.; Liu, Y.; Hendrix, A. R.; Hurley, D.; Cahill, J. T.; Stickle, A. M.; Egan, A.; Kaufmann, D. E.; Grava, C.; Pryor, W. R.

    2016-12-01

    Far ultraviolet reflectance measurements of the Moon, icy satellites, comets, and asteroids obtained within the last decade have ushered in a new era of scientific advancement for UV surface investigations. The Lunar Reconnaissance Orbiter (LRO) Lyman Alpha Mapping Project (LAMP) has demonstrated an innovative nightside observing technique, putting a new light on permanently shadowed regions (PSRs) and other features on the Moon. Dayside far-UV albedo maps complement the nightside data, and LRO's polar orbit and high data downlink capabilities enable searches for diurnal variations in spectral signals. We'll discuss the strengths of the far-UV reflectance imaging spectroscopy technique with respect to several new LAMP results. Detections of water frost and hydration signatures near 165 nm, for example, provide constraints on composition that complement infrared spectroscopy, visible imaging, neutron spectroscopy, radar, and other techniques. At far-UV wavelengths a relatively blue spectral slope is diagnostic of space weathering, which is opposite of the spectral reddening indicator of maturity at wavelengths longward of 180 nm. By utilizing natural diffuse illumination sources on the nightside the far-UV technique is able to identify relative increases in porosity within the PSRs, and provides an additional tool for determining relative surface ages. Prospects for future studies are further enabled by a new, more sensitive dayside operating mode enacted during the present LRO mission extension.

  17. Multi-channel Analysis of Passive Surface Waves (MAPS)

    Science.gov (United States)

    Xia, J.; Cheng, F. Mr; Xu, Z.; Wang, L.; Shen, C.; Liu, R.; Pan, Y.; Mi, B.; Hu, Y.

    2017-12-01

    Urbanization is an inevitable trend in modernization of human society. In the end of 2013 the Chinese Central Government launched a national urbanization plan—"Three 100 Million People", which aggressively and steadily pushes forward urbanization. Based on the plan, by 2020, approximately 100 million people from rural areas will permanently settle in towns, dwelling conditions of about 100 million people in towns and villages will be improved, and about 100 million people in the central and western China will permanently settle in towns. China's urbanization process will run at the highest speed in the urbanization history of China. Environmentally friendly, non-destructive and non-invasive geophysical assessment method has played an important role in the urbanization process in China. Because human noise and electromagnetic field due to industrial life, geophysical methods already used in urban environments (gravity, magnetics, electricity, seismic) face great challenges. But humanity activity provides an effective source of passive seismic methods. Claerbout pointed out that wavefileds that are received at one point with excitation at the other point can be reconstructed by calculating the cross-correlation of noise records at two surface points. Based on this idea (cross-correlation of two noise records) and the virtual source method, we proposed Multi-channel Analysis of Passive Surface Waves (MAPS). MAPS mainly uses traffic noise recorded with a linear receiver array. Because Multi-channel Analysis of Surface Waves can produces a shear (S) wave velocity model with high resolution in shallow part of the model, MPAS combines acquisition and processing of active source and passive source data in a same flow, which does not require to distinguish them. MAPS is also of ability of real-time quality control of noise recording that is important for near-surface applications in urban environment. The numerical and real-world examples demonstrated that MAPS can be

  18. Contribution of body surface mapping to clinical outcome after surgical ablation of postinfarction ventricular tachycardia

    NARCIS (Netherlands)

    van Dessel, Pascal F.; van Hemel, Norbert M.; Groenewegen, Arne Sippens; de Bakker, Jacques M.; Linnebank, André C.; Defauw, Jo J.

    2002-01-01

    This article investigates the influence of body surface mapping on outcome of ventricular antiarrhythmic surgery. Preoperative mapping is advocated to optimize map-guided antiarrhythmic surgery of postinfarction ventricular tachycardia. We sequentially analyzed the results of catheter activation

  19. Dynamic Corneal Surface Mapping with Electronic Speckle Pattern Interferometry

    Science.gov (United States)

    Iqbal, S.; Gualini, M. M. S.

    2013-06-01

    In view of the fast advancement in ophthalmic technology and corneal surgery, there is a strong need for the comprehensive mapping and characterization techniques for corneal surface. Optical methods with precision non-contact approaches have been found to be very useful for such bio measurements. Along with the normal mapping approaches, elasticity of corneal surface has an important role in its characterization and needs to be appropriately measured or estimated for broader diagnostics and better prospective surgical results, as it has important role in the post-op corneal surface reconstruction process. Use of normal corneal topographic devices is insufficient for any intricate analysis since these devices operate at relatively moderate resolution. In the given experiment, Pulsed Electronic Speckle Pattern Interferometry has been utilized along with an excitation mechanism to measure the dynamic response of the sample cornea. A Pulsed ESPI device has been chosen for the study because of its micron-level resolution and other advantages in real-time deformation analysis. A bovine cornea has been used as a sample in the subject experiment. The dynamic response has been taken on a chart recorder and it is observed that it does show a marked deformation at a specific excitation frequency, which may be taken as a characteristic elasticity parameter for the surface of that corneal sample. It was seen that outside resonance conditions the bovine cornea was not that much deformed. Through this study, the resonance frequency and the corresponding corneal deformations are mapped and plotted in real time. In these experiments, data was acquired and processed by FRAMES plus computer analysis system. With some analysis of the results, this technique can help us to refine a more detailed corneal surface mathematical model and some preliminary work was done on this. Such modelling enhancements may be useful for finer ablative surgery planning. After further experimentation

  20. Modelling and Mapping Oxygen-18 Isotope Composition of Precipitation in Spain for Hydrologic and Climatic Applications

    International Nuclear Information System (INIS)

    Rodriguez-Arevalo, J.; Diaz-Teijeiro, M.F.; Castano, S.

    2011-01-01

    A simple multiple regression model based on two geographic factors (latitude and elevation) has been developed that reproduces reasonably well the spatial distribution of the current mean oxygen-18 isotope composition in precipitation over Spain. In a preliminary analysis, additional geographic and climatic factors do not improve the performance of the model. A continuous digital map of oxygen-18 isotope composition in precipitation has been produced by combining the polynomial model with a Digital Elevation Model using GIS tools. Application of the resulting map to several case studies in Spain has shown it to be useful as a reference of the isotope input function to groundwater recharge and surface runoff. The results obtained so far show a good fit between modelled stable isotope values and those measured in surface and ground waters from different aquifers and recharge areas. The GIS tools applied to a continuous digital layer of spatial isotope are able to provide accurate information at detailed scales that are not affordable by other means. Further validation of the model, and further testing of its usefulness in surface hydrology and climatic studies, is going on.

  1. Surface tension of compositions of polyhexametyleneguanidine hydrochloride - surfactants

    Directory of Open Access Journals (Sweden)

    S. Kumargaliyeva

    2012-12-01

    Full Text Available We made up songs bactericidal polyhexamethyleneguanidine hydrochloride (metacyde with the surface-active substances - anionic sodium dodecylsulfate, cationic cetylpyridinium bromide, and nonionic Tween-80 and measured the surface tension of water solutions. The study showed that the composition metacyde with surface-active agents have a greater surface activity than the individual components.

  2. Surface roughness of etched composite resin in light of composite repair

    NARCIS (Netherlands)

    Loomans, B.A.C.; Cardoso, M.V.; Opdam, N.J.M.; Roeters, F.J.M.; Munck, J. De; Huysmans, M.C.D.N.J.M.; Meerbeek, B. Van

    2011-01-01

    OBJECTIVES: In search for clinically effective composite repair protocols, the effect of various etching protocols on the surface roughness of composite resins with different filler composition were investigated. METHODS: Of two composite resins (hybrid-filled Clearfil AP-X; nano-filled Filtek

  3. Glass fibres reinforced polyester composites degradation monitoring by surface analysis

    Energy Technology Data Exchange (ETDEWEB)

    Croitoru, Catalin [“Transilvania” University of Brasov, Materials Engineering and Welding Department, Eroilor 29 Str., 500036 Brasov (Romania); Patachia, Silvia, E-mail: st.patachia@unitbv.ro [“Transilvania” University of Brasov, Product Design Environment and Mechatronics Department, Eroilor 29 Str., 500036 Brasov (Romania); Papancea, Adina [“Transilvania” University of Brasov, Product Design Environment and Mechatronics Department, Eroilor 29 Str., 500036 Brasov (Romania); Baltes, Liana; Tierean, Mircea [“Transilvania” University of Brasov, Materials Engineering and Welding Department, Eroilor 29 Str., 500036 Brasov (Romania)

    2015-12-15

    Highlights: • Glass fibre-reinforced polyester composites surface analysis by photographic method. • The composites are submitted to accelerated ageing by UV irradiation at 254 nm. • The UV irradiation promotes differences in the surface chemistry of the composites. • MB dye is differently adsorbed on surfaces with different degradation degrees. • Good correlation between the colouring degree and surface chemistry. - Abstract: The paper presents a novel method for quantification of the modifications that occur on the surface of different types of gel-coated glass fibre-reinforced polyester composites under artificial UV-ageing at 254 nm. The method implies the adsorption of an ionic dye, namely methylene blue, on the UV-aged composite, and computing the CIELab colour space parameters from the photographic image of the coloured composite's surface. The method significantly enhances the colour differences between the irradiated composites and the reference, in contrast with the non-coloured ones. The colour modifications that occur represent a good indicative of the surface degradation, alteration of surface hydrophily and roughness of the composite and are in good correlation with the ATR-FTIR spectroscopy and optical microscopy results. The proposed method is easier, faster and cheaper than the traditional ones.

  4. Immediate repair bond strengths of microhybrid, nanohybrid and nanofilled composites after different surface treatments

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    Objectives: To evaluate immediate repair bond strengths and failure types of resin composites with and without surface conditioning and characterize the interacting composite surfaces by their surface composition and roughness. Methods: Microhybrid, nanohybrid and nanofilled resin composites were

  5. Explorations in topology map coloring, surfaces and knots

    CERN Document Server

    Gay, David

    2013-01-01

    Explorations in Topology, Second Edition, provides students a rich experience with low-dimensional topology (map coloring, surfaces, and knots), enhances their geometrical and topological intuition, empowers them with new approaches to solving problems, and provides them with experiences that will help them make sense of future, more formal topology courses. The book's innovative story-line style models the problem-solving process, presents the development of concepts in a natural way, and engages students in meaningful encounters with the material. The updated end-of-chapter investigation

  6. Mapping gullies, dunes, lava fields, and landslides via surface roughness

    Science.gov (United States)

    Korzeniowska, Karolina; Pfeifer, Norbert; Landtwing, Stephan

    2018-01-01

    Gully erosion is a widespread and significant process involved in soil and land degradation. Mapping gullies helps to quantify past, and anticipate future, soil losses. Digital terrain models offer promising data for automatically detecting and mapping gullies especially in vegetated areas, although methods vary widely measures of local terrain roughness are the most varied and debated among these methods. Rarely do studies test the performance of roughness metrics for mapping gullies, limiting their applicability to small training areas. To this end, we systematically explored how local terrain roughness derived from high-resolution Light Detection And Ranging (LiDAR) data can aid in the unsupervised detection of gullies over a large area. We also tested expanding this method for other landforms diagnostic of similarly abrupt land-surface changes, including lava fields, dunes, and landslides, as well as investigating the influence of different roughness thresholds, resolutions of kernels, and input data resolution, and comparing our method with previously published roughness algorithms. Our results show that total curvature is a suitable metric for recognising analysed gullies and lava fields from LiDAR data, with comparable success to that of more sophisticated roughness metrics. Tested dunes or landslides remain difficult to distinguish from the surrounding landscape, partly because they are not easily defined in terms of their topographic signature.

  7. COMPOSITE FRIEND SISAL / POLYESTER TREATED IN SURFACE

    Directory of Open Access Journals (Sweden)

    Jayna K. Dionisio Santos

    2011-09-01

    Full Text Available The use of composites in manufacturing equipment and products is taking a very important space in the industry in general. Moreover these materials have unique characteristics when analyzed separately from constituents who are part of them. However it is know that cares must be taken in their manufacture, as the use of appropriate process and the composition of each element, in addition to adherence fiber / matrix, which is a major factor in obtaining of the final mechanical strength of the product. One should also take into account whether the composites are environmentally friendly. For this reason, in this work, a composite partially ecological was made, using as reinforcement, a sisal woven and, as matrix, the polyester resin. Seeking to improve the adherence fiber / matrix, a treatment in sisal woven was performed with aqueous solution of sodium hydroxide (NaOH at a concentration of 3%. The composite subjected to this treatment presented, in bending test, a better mechanical performance, with an increase of 27% in the flexion strength and of 54% in maximum strain, but there was a reduction of about 15% in its flexural modulus.

  8. Mapping surface properties of sinusoidal roughness standards by TPM

    International Nuclear Information System (INIS)

    Liu, X; Rubert, P

    2005-01-01

    We report our investigation on the surface properties of sinusoidal roughness standards made from pure electroformed nickel. Two specimens having a sinusoidal profile with nominal R a of 0.36 μm and a peak spacing of 25 μm are chosen for this investigation. One specimen is further treated with a hard protective coating of nickel-boron. The surface topography, friction, hardness and Young's modulus of the specimens were measured by a novel instrument, the multi-function Tribological Probe Microscope (TPM). The results show that hardness of these two specimens is 14.1 GPa for uncoated specimen and 25.7 GPa for the coated one, while the Young's modulus is 188 GPa and 225 GPa, respectively. The ramping force was set to 3mN for both the specimens and the effect of the tip penetration was investigated by comparing the topography measurements before and after hardness mapping. It has been found out that there is no significant change in the averaged profiles over the scanned area, which indicates the topography distortion seen in the multi-function mapping, is recoverable. Cross correlation between topography and its corresponding hardness/Young's modulus has been carried out and the result will be discussed in the paper

  9. Potentiometric-surface map, 1993, Yucca Mountain and vicinity, Nevada

    International Nuclear Information System (INIS)

    Tucci, P.; Burkhardt, D.J.

    1995-01-01

    The revised potentiometric surface map here, using mainly 1993 average water levels, updates earlier maps of this area. Water levels are contoured with 20-m intervals, with additional 0.5-m contours in the small-gradient area SE of Yucca Mountain. Water levels range from 728 m above sea level SE of Yucca to 1,034 m above sea level north of Yucca. Potentiometric levels in the deeper parts of the volcanic rock aquifer range from 730 to 785 m above sea level. The potentiometric surface can be divided into 3 regions: A small gradient area E and SE of Yucca, a moderate-gradient area on the west side of Yucca, and a large-gradient area to the N-NE of Yucca. Water levels from wells at Yucca were examined for yearly trends (1986-93) using linear least-squares regression. Of the 22 wells, three had significant positive trends. The trend in well UE-25 WT-3 may be influenced by monitoring equipment problems. Tends in USW WT-7 and USW WTS-10 are similar; both are located near a fault west of Yucca; however another well near that fault exhibited no significant trend

  10. Placement suitability criteria of composite tape for mould surface in automated tape placement

    Directory of Open Access Journals (Sweden)

    Zhang Peng

    2015-10-01

    Full Text Available Automated tape placement is an important automated process used for fabrication of large composite structures in aeronautical industry. The carbon fiber composite parts realized with this process tend to replace the aluminum parts produced by high-speed machining. It is difficult to determine the appropriate width of the composite tape in automated tape placement. Wrinkling will appear in the tape if it does not suit for the mould surface. Thus, this paper deals with establishing placement suitability criteria of the composite tape for the mould surface. With the assumptions for ideal mapping and by applying some principles and theorems of differential geometry, the centerline trajectory of the composite tape is identified to follow the geodesic. The placement suitability of the composite tape is examined on three different types of non-developable mould surfaces and four criteria are derived. The developed criteria have been used to test the deposition process over several mould surfaces and the appropriate width for each mould surface is obtained by referring to these criteria.

  11. Surface registration technique for close-range mapping applications

    Science.gov (United States)

    Habib, Ayman F.; Cheng, Rita W. T.

    2006-08-01

    Close-range mapping applications such as cultural heritage restoration, virtual reality modeling for the entertainment industry, and anatomical feature recognition for medical activities require 3D data that is usually acquired by high resolution close-range laser scanners. Since these datasets are typically captured from different viewpoints and/or at different times, accurate registration is a crucial procedure for 3D modeling of mapped objects. Several registration techniques are available that work directly with the raw laser points or with extracted features from the point cloud. Some examples include the commonly known Iterative Closest Point (ICP) algorithm and a recently proposed technique based on matching spin-images. This research focuses on developing a surface matching algorithm that is based on the Modified Iterated Hough Transform (MIHT) and ICP to register 3D data. The proposed algorithm works directly with the raw 3D laser points and does not assume point-to-point correspondence between two laser scans. The algorithm can simultaneously establish correspondence between two surfaces and estimates the transformation parameters relating them. Experiment with two partially overlapping laser scans of a small object is performed with the proposed algorithm and shows successful registration. A high quality of fit between the two scans is achieved and improvement is found when compared to the results obtained using the spin-image technique. The results demonstrate the feasibility of the proposed algorithm for registering 3D laser scanning data in close-range mapping applications to help with the generation of complete 3D models.

  12. Sputtering induced surface composition changes in copper-palladium alloys

    International Nuclear Information System (INIS)

    Sundararaman, M.; Sharma, S.K.; Kumar, L.; Krishnan, R.

    1981-01-01

    It has been observed that, in general, surface composition is different from bulk composition in multicomponent materials as a result of ion beam sputtering. This compositional difference arises from factors like preferential sputtering, radiation induced concentration gradients and the knock-in effect. In the present work, changes in the surface composition of copper-palladium alloys, brought about by argon ion sputtering, have been studied using Auger electron spectroscopy. Argon ion energy has been varied from 500 eV to 5 keV. Enrichment of palladium has been observed in the sputter-altered layer. The palladium enrichment at the surface has been found to be higher for 500 eV argon ion sputtering compared with argon ion sputtering at higher energies. Above 500 eV, the surface composition has been observed to remain the same irrespective of the sputter ion energy for each alloy composition. The bulk composition ratio of palladium to copper has been found to be linearly related to the sputter altered surface composition ratio of palladium to copper. These results are discussed on the basis of recent theories of alloy sputtering. (orig.)

  13. Nonhazardous solvent composition and method for cleaning metal surfaces

    International Nuclear Information System (INIS)

    Googin, J.M.; Simandl, R.F.; Thompson, L.M.

    1993-01-01

    A solvent composition for displacing greasy and oily contaminants as well as water and/or aqueous residue from metallic surfaces, especially surfaces of radioactive materials so that such surfaces can be wiped clean of the displaced contaminants, water and/or aqueous residue. The solvent composition consists essentially of a blend of nonpolar aliphatic hydrocarbon solvent having a minimum flash point of about 140 F and 2 to 25 volume percent of a polar solvent having a flash point sufficiently high so as to provide the solvent composition with a minimum flash point of at least 140 F. The solvent composition is nonhazardous so that when it is used to clean the surfaces of radioactive materials the waste in the form of paper or cloth wipes, lab coats and the like used in the cleaning operation is not considered to be mixed waste composed of a hazardous solvent and a radioactive material

  14. Surface composition of carburized tungsten trioxide and its catalytic activity

    International Nuclear Information System (INIS)

    Nakazawa, M.; Okamoto, H.

    1985-01-01

    The surface composition and electronic structure of carburized tungsten trioxide are investigated using x-ray photoelectron spectroscopy (XPS). The relationship between the surface composition and the catalytic activity for methanol electro-oxidation is clarified. The tungsten carbide concentration in the surface layer increases with the carburization time. The formation of tungsten carbide enhances the catalytic activity. On the other hand, the presence of free carbon or tungsten trioxide in the surface layer reduces the activity remarkably. It is also shown that, the higher the electronic density of states near the Fermi level, the higher the catalytic activity

  15. Hot Surface Ignition of A Composite Fuel Droplet

    Directory of Open Access Journals (Sweden)

    Glushkov Dmitrii O.

    2015-01-01

    Full Text Available The present study examines the characteristics of conductive heating (up to ignition temperature of a composite fuel droplet based on coal, liquid petroleum products, and water. In this paper, we have established the difference between heat transfer from a heat source to a fuel droplet in case of conductive (hot surface and convective (hot gas heat supply. The Leidenfrost effect influences on heat transfer characteristics significantly due to the gas gap between a composite fuel droplet and a hot surface.

  16. Application of Volta potential mapping to determine metal surface defects

    International Nuclear Information System (INIS)

    Nazarov, A.; Thierry, D.

    2007-01-01

    As a rule, stress or fatigue cracks originate from various surface imperfections, such as pits, inclusions or locations showing a residual stress. It would be very helpful for material selection to be able to predict the likelihood of environment-assisted cracking or pitting corrosion. By using Scanning Kelvin Probe (the vibrating capacitor with a spatial resolution of 80 μm) the profiling of metal electron work function (Volta potential) in air is applied to the metal surfaces showing residual stress, MnS inclusions and wearing. The Volta potential is influenced by the energy of electrons at the Fermi level and drops generally across the metal/oxide/air interfaces. Inclusions (e.g. MnS) impair continuity of the passive film that locally decreases Volta potential. The stress applied gives rise to dislocations, microcracks and vacancies in the metal and the surface oxide. The defects decrease Volta and corrosion potentials; reduce the overvoltage for processes of passivity breakdown and anodic metal dissolution. These 'anodic' defects can be visualized in potential mapping that can help us to predict locations with higher risk of pitting corrosion or cracking

  17. Surface characterization of lignocellulosics for composite manufacture

    Science.gov (United States)

    Iyer, Ananth V.

    The objectives of this research were to form moisture resistant wheat strawboards, either by altering the straw surface characteristics or by changing the chemistry of the polymeric 4, 4' diphenylmethane diisocyanate (PMDI)-based matrix and interface. Part I compared the surface characteristics of wheat, barley, oat, rice, kenaf, hemp and softwood particles. All cereal straws had two surfaces: epidermis and brittle-pith unlike one heterogeneous type observed for bast fibers and softwood particles. The epidermis of cereal straws was not wet by water or aqueous binders, whereas the pith surface allowed the penetration of water, but was not readily wetted by aqueous binders. Between the different surface treatments evaluated for wheat straw in Part II, NaOH selectively peeled-off the epidermis and pith layers. The treated straw particles were formable into strawboards using aqueous phenol-formaldehyde, urea-formaldehyde, and duroplastic acrylic acid binders with good internal bond strength (IBS) and adequate water resistance. In Part III it was shown that, decreasing straw particle sizes and bleaching worsened the mechanical properties of strawboards, but the moisture absorption properties of bleached strawboards were lower than the unbleached ones. Layering of straw particles in strawboards did not seem to affect their mechanical or moisture absorption properties. Part IV showed that the pith surface of wheat straw was fractured on curing with PMDI, providing hollow microcrevices for water accumulation. Furthermore, the cured PMDI formed a network polyurea/polyuretonimine/polycarbodiimide/polyisocyanurate polymer on straw surfaces whose properties dictated the properties of strawboards. Among the different mono-, bi-, and tri-functional alcohols, amines and carboxylic acids evaluated in Part V as H-donor substitutes to moisture for reaction with PMDI on straw surfaces, ethylene glycol, resorcinol, glycerin and citric acid provided IBS values greater than the ANSI

  18. Photoinduced surface voltage mapping study for large perovskite single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaojing; Liu, Yucheng; Gao, Fei; Yang, Zhou [Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, Shaanxi Engineering Laboratory for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Liu, Shengzhong, E-mail: liusz@snnu.edu.cn [Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, Shaanxi Engineering Laboratory for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Dalian Institute of Chemical Physics, iChEM, Dalian National Laboratory for Clean Energy, Chinese Academy of Sciences, Dalian 116023 (China)

    2016-05-02

    Using a series of illumination sources, including white light (tungsten-halogen lamp), 445-nm, 532-nm, 635-nm, and 730-nm lasers, the surface photovoltage (SPV) images were mapped for centimeter-sized CH{sub 3}NH{sub 3}PbX{sub 3} (X = Cl, Br, I) perovskite single crystals using Kelvin probe force microscopy. The significant SPV signals were observed to be wavelength-dependent. We attribute the appreciable SPV to the built-in electric field in the space charge region. This study shines light into the understanding of photoinduced charge generation and separation processes at nanoscale to help advance the development of perovskite solar cells, optoelectronics, laser, photodetector, and light-emitting diode (LED).

  19. Revised potentiometric-surface map, Yucca Mountain and vicinity, Nevada

    International Nuclear Information System (INIS)

    Ervin, E.M.; Luckey, R.R.; Burkhardt, D.J.

    1994-01-01

    The revised potentiometric-surface map presented in this report updates earlier maps of the Yucca Mountain area using mainly 1988 average water levels. Because of refinements in the corrections to the water-level measurements, these water levels have increased accuracy and precision over older values. The small-gradient area to the southeast of Yucca Mountain is contoured with a 0.25-meter interval and ranges in water-level altitude from 728.5 to 73 1.0 meters. Other areas with different water levels, to the north and west of Yucca Mountain, are illustrated with shaded patterns. The potentiometric surface can be divided into three regions: (1) A small-gradient area to the southeast of Yucca Mountain, which may be explained by flow through high-transmissivity rocks or low ground-water flux through the area; (2) A moderate-gradient area, on the western side of Yucca Mountain, where the water-level altitude ranges from 775 to 780 meters, and appears to be impeded by the Solitario Canyon Fault and a splay of that fault; and (3) A large-gradient area, to the north-northeast of Yucca Mountain, where water level altitude ranges from 738 to 1,035 meters, possibly as a result of a semi-perched groundwater system. Water levels from wells at Yucca Mountain were examined for yearly trends using linear least-squares regression. Data from five wells exhibited trends which were statistically significant, but some of those may be a result of slow equilibration of the water level from drilling in less permeable rocks. Adjustments for temperature and density changes in the deep wells with long fluid columns were attempted, but some of the adjusted data did not fit the surrounding data and, thus, were not used

  20. Continuous Natural Fiber Reinforced Thermoplastic Composites by Fiber Surface Modification

    Directory of Open Access Journals (Sweden)

    Patcharat Wongsriraksa

    2013-01-01

    Full Text Available Continuous natural fiber reinforced thermoplastic materials are expected to replace inorganic fiber reinforced thermosetting materials. However, in the process of fabricating the composite, it is difficult to impregnate the thermoplastic resin into reinforcement fiber because of the high melt viscosity. Therefore, intermediate material, which allows high impregnation during molding, has been investigated for fabricating continuous fiber reinforced thermoplastic composite by aligning resin fiber alongside reinforcing fiber with braiding technique. This intermediate material has been called “microbraid yarn (MBY.” Moreover, it is well known that the interfacial properties between natural fiber and resin are low; therefore, surface treatment on continuous natural fiber was performed by using polyurethane (PU and flexible epoxy (FLEX to improve the interfacial properties. The effect of surface treatment on the mechanical properties of continuous natural fiber reinforced thermoplastic composites was examined. From these results, it was suggested that surface treatment by PU with low content could produce composites with better mechanical properties.

  1. Surface characterization of current composites after toothbrush abrasion.

    Science.gov (United States)

    Takahashi, Rena; Jin, Jian; Nikaido, Toru; Tagami, Junji; Hickel, Reinhard; Kunzelmann, Karl-Heinz

    2013-01-01

    The present study was designed to evaluate the surface roughness and the gloss of current composites before and after toothbrush abrasion. We assessed forty dimensionally standardized composite specimens (n=8/group) from five composites: two nanohybrids (i. e., IPS Empress Direct Enamel and IPS Empress Direct Dentin), two microhybrids (i. e., Clearfil AP-X and Filtek Z250) and one organically modified ceramics (Admira). All of the specimens were polished with 4000-grid silicon carbide papers. Surface roughness was measured with a profilometer and gloss was measured with a glossmeter before and after powered toothbrush abrasion with a 1:1 slurry (dentifrice/tap water) at 12,000 strokes in a toothbrush simulator. There was a significant increase in the surface roughness and a reduction in gloss after toothbrush abrasion in all of the composites except Clearfil AP-X (pgloss (R(2)=0.191, p<0.001).

  2. Titan's Surface Temperatures Maps from Cassini - CIRS Observations

    Science.gov (United States)

    Cottini, Valeria; Nixon, C. A.; Jennings, D. E.; Anderson, C. M.; Samuelson, R. E.; Irwin, P. G. J.; Flasar, F. M.

    2009-09-01

    The Cassini Composite Infrared Spectrometer (CIRS) observations of Saturn's largest moon, Titan, are providing us with the ability to detect the surface temperature of the planet by studying its outgoing radiance through a spectral window in the thermal infrared at 19 μm (530 cm-1) characterized by low opacity. Since the first acquisitions of CIRS Titan data the instrument has gathered a large amount of spectra covering a wide range of latitudes, longitudes and local times. We retrieve the surface temperature and the atmospheric temperature profile by modeling proper zonally averaged spectra of nadir observations with radiative transfer computations. Our forward model uses the correlated-k approximation for spectral opacity to calculate the emitted radiance, including contributions from collision induced pairs of CH4, N2 and H2, haze, and gaseous emission lines (Irwin et al. 2008). The retrieval method uses a non-linear least-squares optimal estimation technique to iteratively adjust the model parameters to achieve a spectral fit (Rodgers 2000). We show an accurate selection of the wide amount of data available in terms of footprint diameter on the planet and observational conditions, together with the retrieved results. Our results represent formal retrievals of surface brightness temperatures from the Cassini CIRS dataset using a full radiative transfer treatment, and we compare to the earlier findings of Jennings et al. (2009). In future, application of our methodology over wide areas should greatly increase the planet coverage and accuracy of our knowledge of Titan's surface brightness temperature. References: Irwin, P.G.J., et al.: "The NEMESIS planetary atmosphere radiative transfer and retrieval tool" (2008). JQSRT, Vol. 109, pp. 1136-1150, 2008. Rodgers, C. D.: "Inverse Methods For Atmospheric Sounding: Theory and Practice". World Scientific, Singapore, 2000. Jennings, D.E., et al.: "Titan's Surface Brightness Temperatures." Ap. J. L., Vol. 691, pp. L103-L

  3. Surface functionalized hollow silica particles and composites

    KAUST Repository

    Rodionov, Valentin; Khanh, Vu Bao

    2017-01-01

    Composition comprising hollow spherical silica particles having outside particle walls and inside particle walls, wherein the particles have an average particle size of about 10 nm to about 500 nm and an average wall thickness of about 10 nm to about 50 nm; and wherein the particles are functionalized with at least one organic functional group on the outside particle wall, on the inside particle wall, or on both the outside and inside particle walls, wherein the organic functional group is in a reacted or unreacted form. The organic functional group can be epoxy. The particles can be mixed with polymer precursor or a polymer material such as epoxy to form a prepreg or a nanocomposite. Lightweight but strong materials can be formed. Low loadings of hollow particles can be used.

  4. Surface functionalized hollow silica particles and composites

    KAUST Repository

    Rodionov, Valentin

    2017-05-26

    Composition comprising hollow spherical silica particles having outside particle walls and inside particle walls, wherein the particles have an average particle size of about 10 nm to about 500 nm and an average wall thickness of about 10 nm to about 50 nm; and wherein the particles are functionalized with at least one organic functional group on the outside particle wall, on the inside particle wall, or on both the outside and inside particle walls, wherein the organic functional group is in a reacted or unreacted form. The organic functional group can be epoxy. The particles can be mixed with polymer precursor or a polymer material such as epoxy to form a prepreg or a nanocomposite. Lightweight but strong materials can be formed. Low loadings of hollow particles can be used.

  5. Mineralogy of the Martian Surface: Crustal Composition to Surface Processes

    Science.gov (United States)

    Mustard, John F.

    1999-01-01

    Over the course of this award we have: 1) Completed and published the results of a study of the effects of hyperfine particles on reflectance spectra of olivine and quartz, which included the development of scattering codes. Research has also progressed in the analysis of the effects of fine particle sizes on clay spectra. 2) Completed the analysis of the mineralogy of dark regions, showed the insitu compositions are highly correlated to the SNC meteorites, and determined that the martian mantle was depleted in aluminum prior to 2-3 GA ago; Studies of the mineralogic heterogeneity of surficial materials on Mars have also been conducted. and 3) Performed initial work on the study of the physical and chemical processes likely to form and modify duricrust. This includes assessments of erosion rates, solubility and transport of iron in soil environments, and models of pedogenic crust formation.

  6. Surface roughness of composite resins subjected to hydrochloric acid.

    Science.gov (United States)

    Roque, Ana Carolina Cabral; Bohner, Lauren Oliveira Lima; de Godoi, Ana Paula Terossi; Colucci, Vivian; Corona, Silmara Aparecida Milori; Catirse, Alma Blásida Concepción Elizaur Benitez

    2015-01-01

    The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence. Acid challenge was performed by immersion of specimens in hydrochloric acid (pH 1.2) for 1 min, 4 times per day for 7 days. The specimens not subjected to acid challenge were stored in 15 mL of artificial saliva at 37 oC. Afterwards, all specimens were submitted to abrasive challenge by a brushing cycle performed with a 200 g weight at a speed of 356 rpm, totaling 17.8 cycles. Surface roughness measurements (Ra) were performed and analyzed by ANOVA and Tukey test (p≤0.05). Surface roughness values were higher in the presence (1.07±0.24) as compared with the absence of hydrochloric acid (0.72±0.04). Surface roughness values were higher for microhybrid (1.01±0.27) compared with nanofilled (0.68 ±0.09) and nanohybrid (0.48±0.15) composites when the specimens were not subjects to acid challenge. In the presence of hydrochloric acid, microhybrid (1.26±0.28) and nanofilled (1.18±0,30) composites presents higher surface roughness values compared with nanohybrid (0.77±0.15). The hydrochloric acid affected the surface roughness of composite resin subjected to brushing.

  7. Nephele: genotyping via complete composition vectors and MapReduce

    Directory of Open Access Journals (Sweden)

    Mardis Scott

    2011-08-01

    Full Text Available Abstract Background Current sequencing technology makes it practical to sequence many samples of a given organism, raising new challenges for the processing and interpretation of large genomics data sets with associated metadata. Traditional computational phylogenetic methods are ideal for studying the evolution of gene/protein families and using those to infer the evolution of an organism, but are less than ideal for the study of the whole organism mainly due to the presence of insertions/deletions/rearrangements. These methods provide the researcher with the ability to group a set of samples into distinct genotypic groups based on sequence similarity, which can then be associated with metadata, such as host information, pathogenicity, and time or location of occurrence. Genotyping is critical to understanding, at a genomic level, the origin and spread of infectious diseases. Increasingly, genotyping is coming into use for disease surveillance activities, as well as for microbial forensics. The classic genotyping approach has been based on phylogenetic analysis, starting with a multiple sequence alignment. Genotypes are then established by expert examination of phylogenetic trees. However, these traditional single-processor methods are suboptimal for rapidly growing sequence datasets being generated by next-generation DNA sequencing machines, because they increase in computational complexity quickly with the number of sequences. Results Nephele is a suite of tools that uses the complete composition vector algorithm to represent each sequence in the dataset as a vector derived from its constituent k-mers by passing the need for multiple sequence alignment, and affinity propagation clustering to group the sequences into genotypes based on a distance measure over the vectors. Our methods produce results that correlate well with expert-defined clades or genotypes, at a fraction of the computational cost of traditional phylogenetic methods run on

  8. Galileo's Multiinstrument Spectral View of Europa's Surface Composition

    Science.gov (United States)

    Fanale, F.P.; Granahan, J.C.; McCord, T.B.; Hansen, G.; Hibbitts, C.A.; Carlson, R.; Matson, D.; Ocampo, A.; Kamp, L.; Smythe, W.; Leader, F.; Mehlman, R.; Greeley, R.; Sullivan, R.; Geissler, P.; Barth, C.; Hendrix, A.; Clark, B.; Helfenstein, P.; Veverka, J.; Belton, M.J.S.; Becker, K.; Becker, T.

    1999-01-01

    We have combined spectral reflectance data from the Solid State Imaging (SSI) experiment, the Near-Infrared Mapping Spectrometer (NIMS), and the Ultraviolet Spectrometer (UVS) in an attempt to determine the composition and implied genesis of non-H2O components in the optical surface of Europa. We have considered four terrains: (1) the "dark terrains" on the trailing hemisphere, (2) the "mottled terrain," (3) the linea on the leading hemisphere, and (4) the linea embedded in the dark terrain on the trailing hemisphere. The darker materials in these terrains exhibit remarkably similar spectra in both the visible and near infrared. In the visible, a downturn toward shorter wavelengths has been attributed to sulfur. The broad concentrations of dark material on the trailing hemisphere was originally thought to be indicative of exogenic sulfur implantation. While an exogenic cause is still probable, more recent observations by the UVS team at higher spatial resolution have led to their suggestions that the role of the bombardment may have primarily been to sputter away overlying ice and to reveal underlying endogenic non-H2O contaminants. If so, this might explain why the spectra in all these terrains are so similar despite the fact that the contaminants in the linea are clearly endogenic and those in the mottled terrain are almost certainly so. In the near infrared, all these terrains exhibit much more asymmetrical bands at 1.4 and 2.0 ??m at shorter wavelengths than spectra from elsewhere on Europa. It has been argued that this is because the water molecules are bound in hydrated salts. However, this interpretation has been challenged and it has also been argued that pure coarse ice can exhibit such asymmetric bands under certain conditions. The nature of this controversy is briefly discussed, as are theoretical and experimental studies bearing on this problem. ?? 1999 Academic Press.

  9. Solar Imagery - Composites - Synoptic Maps - McIntosh

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In 1964 (solar cycle 20) Patrick McIntosh began creating hand-drawn synoptic maps of solar activity, based on Hydrogen alpha (H?) imaging measurements. These...

  10. Quantitative mapping of chemical compositions with MRI using compressed sensing.

    Science.gov (United States)

    von Harbou, Erik; Fabich, Hilary T; Benning, Martin; Tayler, Alexander B; Sederman, Andrew J; Gladden, Lynn F; Holland, Daniel J

    2015-12-01

    In this work, a magnetic resonance (MR) imaging method for accelerating the acquisition time of two dimensional concentration maps of different chemical species in mixtures by the use of compressed sensing (CS) is presented. Whilst 2D-concentration maps with a high spatial resolution are prohibitively time-consuming to acquire using full k-space sampling techniques, CS enables the reconstruction of quantitative concentration maps from sub-sampled k-space data. First, the method was tested by reconstructing simulated data. Then, the CS algorithm was used to reconstruct concentration maps of binary mixtures of 1,4-dioxane and cyclooctane in different samples with a field-of-view of 22mm and a spatial resolution of 344μm×344μm. Spiral based trajectories were used as sampling schemes. For the data acquisition, eight scans with slightly different trajectories were applied resulting in a total acquisition time of about 8min. In contrast, a conventional chemical shift imaging experiment at the same resolution would require about 17h. To get quantitative results, a careful weighting of the regularisation parameter (via the L-curve approach) or contrast-enhancing Bregman iterations are applied for the reconstruction of the concentration maps. Both approaches yield relative errors of the concentration map of less than 2mol-% without any calibration prior to the measurement. The accuracy of the reconstructed concentration maps deteriorates when the reconstruction model is biased by systematic errors such as large inhomogeneities in the static magnetic field. The presented method is a powerful tool for the fast acquisition of concentration maps that can provide valuable information for the investigation of many phenomena in chemical engineering applications. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Global Distribution of Shallow Water on Mars: Neutron Mapping of Summer-Time Surface by HEND/Odyssey

    Science.gov (United States)

    Mitrofanov, I. G.; Litvak, M. L.; Kozyrev, A. S.; Sanin, A. B.; Tretyakov, V. I.; Boynton, W.; Hamara, D.; Shinohara, C.; Saunders, R. S.; Drake, D.

    2003-01-01

    Orbital mapping of induced neutrons and gamma-rays by Odyssey has recently successfully proven the applicability of nuclear methods for studying of the elementary composition of Martian upper-most subsurface. In particular, the suite of Gamma-Ray Spectrometer (GRS) has discovered the presence of large water-ice rich regions southward and northward on Mars. The data of neutron mapping of summer-time surface are presented below from the Russian High Energy Neutron Spectrometer (HEND), which is a part of GRS suite. These maps represent the content of water in the soil for summer season at Southern and Northern hemispheres, when the winter deposit of CO2 is absent on the surface. The seasonal evolution of CO2 coverage on Mars is the subject of the complementary paper.

  12. What controls the isotopic composition of Greenland surface snow?

    Directory of Open Access Journals (Sweden)

    H. C. Steen-Larsen

    2014-02-01

    Full Text Available Water stable isotopes in Greenland ice core data provide key paleoclimatic information, and have been compared with precipitation isotopic composition simulated by isotopically enabled atmospheric models. However, post-depositional processes linked with snow metamorphism remain poorly documented. For this purpose, monitoring of the isotopic composition (δ18O, δD of near-surface water vapor, precipitation and samples of the top (0.5 cm snow surface has been conducted during two summers (2011–2012 at NEEM, NW Greenland. The samples also include a subset of 17O-excess measurements over 4 days, and the measurements span the 2012 Greenland heat wave. Our observations are consistent with calculations assuming isotopic equilibrium between surface snow and water vapor. We observe a strong correlation between near-surface vapor δ18O and air temperature (0.85 ± 0.11‰ °C−1 (R = 0.76 for 2012. The correlation with air temperature is not observed in precipitation data or surface snow data. Deuterium excess (d-excess is strongly anti-correlated with δ18O with a stronger slope for vapor than for precipitation and snow surface data. During nine 1–5-day periods between precipitation events, our data demonstrate parallel changes of δ18O and d-excess in surface snow and near-surface vapor. The changes in δ18O of the vapor are similar or larger than those of the snow δ18O. It is estimated using the CROCUS snow model that 6 to 20% of the surface snow mass is exchanged with the atmosphere. In our data, the sign of surface snow isotopic changes is not related to the sign or magnitude of sublimation or deposition. Comparisons with atmospheric models show that day-to-day variations in near-surface vapor isotopic composition are driven by synoptic variations and changes in air mass trajectories and distillation histories. We suggest that, in between precipitation events, changes in the surface snow isotopic composition are driven by these changes in near-surface

  13. Tribological behaviors of UHMWPE composites with different counter surface morphologies

    Science.gov (United States)

    Wang, Yanzhen; Yin, Zhongwei; Li, Hulin; Gao, Gengyuan

    2017-12-01

    The influence of counter surface morphologies on hybrid glass fiber (GF) and carbon fiber (CF) filled ultrahigh molecular weight polyethylene (UHMWPE) were studied under various contact pressure and sliding speed against GCr15 steel in dry condition. The goals were to investigate the tribological behavior of GF/CF/UHMWPE composite as a kind of water lubricated journal bearing material. The friction and wear behavior of composites were examined using a pin-on-disc tribometer. The morphologies of the worn surface were examined by scanning electron microscopy (SEM) and laser 3D micro-imaging and profile measurement. Generally, the wear rate and friction coefficient of composites increase as the increment of counter surface roughness. The friction coefficient increases firstly and then decrease with an increase in sliding speed and contact pressure for counterface with Ra=0.2 and 3.5 μm, while the friction coefficient decreased for counterface with Ra=0.6 μm.

  14. Heat capacity mapping mission (HCMM) thermal surface water mapping and its correlation to LANDSAT

    International Nuclear Information System (INIS)

    Colvocoresses, A.P.

    1980-03-01

    Graphics are presented which show HCMM mapped water-surface temperature in Lake Anna, a 13,000 dendrically-shaped lake which provides cooling for a nuclear power plant in Virginia. The HCMM digital data, produced by NASA were processed by NOAA/NESS into image and line-printer form. A LANDSAT image of the lake illustrates the relationship between MSS band 7 data and the HCMM data as processed by the NASA image processing facility which transforms the data to the same distortion-free hotline oblique Mercator projection. Spatial correlation of the two images is relatively simple by either digital or analog means and the HCMM image has a potential accuracy approaching the 80 m of the original LANDSAT data. While it is difficult to get readings that are not diluted by radiation from cooler adjacent land areas in narrow portions of the lake, digital data indicated by the line-printer display five different temperatures for open-water areas. Where the water surface response was not diluted by land areas, the temperature difference recorded by HCMM corresponds to in situ readings with rsme on the order of 1 C

  15. Cancer Risk Map for the Surface of Mars

    Science.gov (United States)

    Kim, Myung-Hee Y.; Cucinotta, Francis A.

    2011-01-01

    We discuss calculations of the median and 95th percentile cancer risks on the surface of Mars for different solar conditions. The NASA Space Radiation Cancer Risk 2010 model is used to estimate gender and age specific cancer incidence and mortality risks for astronauts exploring Mars. Organ specific fluence spectra and doses for large solar particle events (SPE) and galactic cosmic rays (GCR) at various levels of solar activity are simulated using the HZETRN/QMSFRG computer code, and the 2010 version of the Badhwar and O Neill GCR model. The NASA JSC propensity model of SPE fluence and occurrence is used to consider upper bounds on SPE fluence for increasing mission lengths. In the transport of particles through the Mars atmosphere, a vertical distribution of Mars atmospheric thickness is calculated from the temperature and pressure data of Mars Global Surveyor, and the directional cosine distribution is implemented to describe the spherically distributed atmospheric distance along the slant path at each elevation on Mars. The resultant directional shielding by Mars atmosphere at each elevation is coupled with vehicle and body shielding for organ dose estimates. Astronaut cancer risks are mapped on the global topography of Mars, which was measured by the Mars Orbiter Laser Altimeter. Variation of cancer risk on the surface of Mars is due to a 16-km elevation range, and the large difference is obtained between the Tharsis Montes (Ascraeus, Pavonis, and Arsia) and the Hellas impact basin. Cancer incidence risks are found to be about 2-fold higher than mortality risks with a disproportionate increase in skin and thyroid cancers for all astronauts and breast cancer risk for female astronauts. The number of safe days on Mars to be below radiation limits at the 95th percent confidence level is reported for several Mission design scenarios.

  16. A coastal surface seawater analyzer for nitrogenous nutrient mapping

    Science.gov (United States)

    Masserini, Robert T.; Fanning, Kent A.; Hendrix, Steven A.; Kleiman, Brittany M.

    2017-11-01

    Satellite-data-based modeling of chlorophyll indicates that ocean waters in the mesosphere category are responsible for the majority of oceanic net primary productivity. Coastal waters, which frequently have surface chlorophyll values in the mesosphere range and have strong horizontal chlorophyll gradients and large temporal variations. Thus programs of detailed coastal nutrient surveys are essential to the study of the dynamics of oceanic net primary productivity, along with land use impacts on estuarine and coastal ecosystems. The degree of variability in these regions necessitates flexible instrumentation capable of near real-time analysis to detect and monitor analytes of interest. This work describes the development of a portable coastal surface seawater analyzer for nutrient mapping that can simultaneously elucidate with high resolution the distribution of nitrate, nitrite, and ammonium - the three principal nitrogenous inorganic nutrients in coastal systems. The approach focuses on the use of pulsed xenon flash lamps to construct an analyzer which can be adapted to any automated chemistry with fluorescence detection. The system has two heaters, on-the-fly standardization, on-board data logging, an independent 24 volt direct current power supply, internal local operating network, a 12 channel peristaltic pump, four rotary injection/selection valves, and an intuitive graphical user interface. Using the methodology of Masserini and Fanning (2000) the detection limits for ammonium, nitrite, and nitrate plus nitrite were 11, 10, and 22 nM, respectively. A field test of the analyzer in Gulf of Mexico coastal waters demonstrated its ability to monitor and delineate the complexity of inorganic nitrogen nutrient enrichments within a coastal system.

  17. IRAS surface brightness maps of reflection nebulae in the Pleiades

    Science.gov (United States)

    Castelaz, Michael W.; Werner, M. W.; Sellgren, K.

    1987-01-01

    Surface brightness maps at 12, 25, 60, and 100 microns were made of a 2.5 deg x 2.5 deg area of the reflection nebulae in the Pleiades by coadding IRAS scans of this region. Emission is seen surrounding 17 Tau, 20 Tau, 23 Tau, and 25 Tau in all four bands, coextensive with the visible reflection nebulosity, and extending as far as 30 arcminutes from the illuminating stars. The infrared energy distributions of the nebulae peak in the 100 micron band, but up to 40 percent of the total infrared power lies in the 12 and 25 micron bands. The brightness of the 12 and 25 micron emission and the absence of temperature gradients at these wavelengths are inconsistent with the predictions of equilibrium thermal emission models. The emission at these wavelengths appears to be the result of micron nonequilibrium emission from very small grains, or from molecules consisting of 10-100 carbon atoms, which have been excited by ultraviolet radiation from the illuminating stars.

  18. Reversible Compositional Control of Oxide Surfaces by Electrochemical Potentials

    KAUST Repository

    Mutoro, Eva

    2012-01-05

    Perovskite oxides can exhibit a wide range of interesting characteristics such as being catalytically active and electronically/ionically conducting, and thus, they have been used in a number of solid-state devices such as solid oxide fuel cells (SOFCs) and sensors. As the surface compositions of perovskites can greatly influence the catalytic properties, knowing and controlling their surface compositions is crucial to enhance device performance. In this study, we demonstrate that the surface strontium (Sr) and cobalt (Co) concentrations of perovskite-based thin films can be controlled reversibly at elevated temperatures by applying small electrical potential biases. The surface compositional changes of La 0.8Sr 0.2CoO 3-δ (LSC 113), (La 0.5Sr 0.5) 2CoO 4±δ (LSC 214), and LSC 214-decorated LSC 113 films (LSC 113/214) were investigated in situ by utilizing synchrotron-based X-ray photoelectron spectroscopy (XPS), where the largest changes of surface Sr were found for the LSC 113/214 surface. These findings offer the potential of reversibly controlling the surface functionality of perovskites. © 2011 American Chemical Society.

  19. Surface analysis of graphite fiber reinforced polyimide composites

    Science.gov (United States)

    Messick, D. L.; Progar, D. J.; Wightman, J. P.

    1983-01-01

    Several techniques have been used to establish the effect of different surface pretreatments on graphite-polyimide composites. Composites were prepared from Celion 6000 graphite fibers and the polyimide LARC-160. Pretreatments included mechanical abrasion, chemical etching and light irradiation. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used in the analysis. Contact angle of five different liquids of varying surface tensions were measured on the composites. SEM results showed polymer-rich peaks and polymer-poor valleys conforming to the pattern of the release cloth used durng fabrication. Mechanically treated and light irradiated samples showed varying degrees of polymer peak removal, with some degradation down to the graphite fibers. Minimal changes in surface topography were observed on concentrations of surface fluorine even after pretreatment. The light irradiation pretreatment was most effective at reducing surface fluorine concentrations whereas chemical pretreatment was the least effective. Critical surface tensions correlated directly with the surface fluorine to carbon ratios as calculated from XPS.

  20. Surface characterization of modern resin composites: a multitechnique approach.

    Science.gov (United States)

    Silikas, Nick; Kavvadia, Katerina; Eliades, George; Watts, David

    2005-04-01

    To characterize the surface properties of some modern resin composites employing a series of physicochemical methods. Specimens from three microhybrid (Palfique Estellite-PE, Z250 Filtek-ZF, Tetric Ceram-TC) and one nanofilled (Supreme Filtek-SF) conventionally photo-cured resin composites polished with Soflex disks were studied for the following properties: Surface chemical composition and degree of C=C conversion (FTIR), surface energetics (contact angles), surface texture (AFM), surface roughness (AFM, stylus profilometry) and gloss (60 degrees-, 20 degrees-angle specular gloss). Polar and non polar molecular groups were identified in all products including NH and CONH (SF, ZF, TC). SF and ZF demonstrated higher conversion than PE and TC (P 0.05) were found in critical surface tension, total work of adhesion and its polar and dispersion components, the latter being the highest in all products. AFM showed the smoothest surface texture in PE. The ranking of Sa, Sq, Ra and Rz roughness parameters was PEgloss measurements (PE, SF>ZF>TC, PTC, Pgloss differences. A positive correlation was found between Sa and Ra and a negative one between Sa and 20 degree-angle gloss.

  1. Rapid Construction of Fe-Co-Ni Composition-Phase Map by Combinatorial Materials Chip Approach.

    Science.gov (United States)

    Xing, Hui; Zhao, Bingbing; Wang, Yujie; Zhang, Xiaoyi; Ren, Yang; Yan, Ningning; Gao, Tieren; Li, Jindong; Zhang, Lanting; Wang, Hong

    2018-03-12

    One hundred nanometer thick Fe-Co-Ni material chips were prepared and isothermally annealed at 500, 600, and 700 °C, respectively. Pixel-by-pixel composition and structural mapping was performed by microbeam X-ray at synchrotron light source. Diffraction images were recorded at a rate of 1 pattern/s. The XRD patterns were automatically processed, phase-identified, and categorized by hierarchical clustering algorithm to construct the composition-phase map. The resulting maps are consistent with corresponding isothermal sections reported in the ASM Alloy Phase Diagram Database, verifying the effectiveness of the present approach in phase diagram construction.

  2. Surface treated fly ash filled modified epoxy composites

    Directory of Open Access Journals (Sweden)

    Uma Dharmalingam

    2015-01-01

    Full Text Available Abstract Fly ash, an inorganic alumino silicate has been used as filler in epoxy matrix, but it reduces the mechanical properties due to its poor dispersion and interfacial bonding with the epoxy matrix. To improve its interfacial bonding with epoxy matrix, surface treatment of fly ash was done using surfactant sodium lauryl sulfate and silane coupling agent glycidoxy propyl trimethoxy silane. An attempt is also made to reduce the particle size of fly ash using high pressure pulverizer. To improve fly ash dispersion in epoxy matrix, the epoxy was modified by mixing with amine containing liquid silicone rubber (ACS. The effect of surface treated fly ash with varying filler loadings from 10 to 40% weight on the mechanical, morphological and thermal properties of modified epoxy composites was investigated. The surface treated fly ash was characterized by particle size analyzer and FTIR spectra. Morphological studies of surface treated fly ash filled modified epoxy composites indicate good dispersion of fillers in the modified epoxy matrix and improves its mechanical properties. Impact strength of the surface treated fly ash filled modified epoxy composites show more improvement than unmodified composites.

  3. Method and coating composition for protecting and decontaminating surfaces

    Science.gov (United States)

    Overhold, D C; Peterson, M D

    1959-03-10

    A protective coating useful in the decontamination of surfaces exposed to radioactive substances is described. This coating is placed on the surface before use and is soluble in water, allowing its easy removal in the event decontamination becomes necessary. Suitable coating compositions may be prepared by mixing a water soluble carbohydrate such as sucrose or dextrin, together with a hygroscopic agent such as calcium chloride or zinc chloride.

  4. Simultaneous Localization and Mapping for Planetary Surface Mobility, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC and Carnegie Mellon University have formed a partnership to commercially develop localization and mapping technologies for planetary rovers....

  5. Strength and failure analysis of composite-to-composite adhesive bonds with different surface treatments

    Science.gov (United States)

    Paranjpe, Nikhil; Alamir, Mohammed; Alonayni, Abdullah; Asmatulu, Eylem; Rahman, Muhammad M.; Asmatulu, Ramazan

    2018-03-01

    Adhesives are widely utilized materials in aviation, automotive, energy, defense, and marine industries. Adhesive joints are gradually supplanting mechanical fasteners because they are lightweight structures, thus making the assembly lighter and easier. They also act as a sealant to prevent a structural joint from galvanic corrosion and leakages. Adhesive bonds provide high joint strength because of the fact that the load is distributed uniformly on the joint surface, while in mechanical joints, the load is concentrated at one point, thus leading to stress at that point and in turn causing joint failures. This research concentrated on the analysis of bond strength and failure loads in adhesive joint of composite-to-composite surfaces. Different durations of plasma along with the detergent cleaning were conducted on the composite surfaces prior to the adhesive applications and curing processes. The joint strength of the composites increased about 34% when the surface was plasma treated for 12 minutes. It is concluded that the combination of different surface preparations, rather than only one type of surface treatment, provides an ideal joint quality for the composites.

  6. Electrocardiographic markers of ischemia during mental stress testing in postinfarction patients. Role of body surface mapping

    International Nuclear Information System (INIS)

    Bosimini, E.; Galli, M.; Guagliumi, G.; Giubbini, R.; Tavazzi, L.

    1991-01-01

    In patients with coronary artery disease, radionuclide investigations have documented a high incidence of mental stress-induced myocardial ischemia in the absence of significant electrocardiographic changes and/or angina. To investigate the causes of the low electrocardiographic sensitivity, we recorded body surface maps during mental arithmetic in 22 normal volunteers and 37 postinfarction patients with residual exercise ischemia. Myocardial perfusion was studied with thallium-201 or technetium-99 (SESTAMIBI) planar scans. In 14 patients, body surface maps were also recorded during atrial pacing at the heart rate values achieved during mental stress. While taking the body surface maps, the area from J point to 80 msec after this point (ST-80) was analyzed by integral maps, difference maps, and departure maps. The body surface mapping criteria for ischemia were a new negative area on the integral maps, a negative potential of more than 2 SD from mean normal values on the difference maps, and a negative departure index of more than 2. Scintigraphy showed asymptomatic myocardial hypoperfusion in 33 patients. Eight patients had significant ST segment depression. The ST-80 integral and difference maps identified 17 ischemic patients. Twenty-four patients presented abnormal departure maps. One patient presented ST depression and abnormal body surface maps without reversible tracer defect. In 14 of 14 patients, atrial pacing did not reproduce the body surface map abnormalities. The analyses of the other electrocardiographic variables showed that in patients with mental stress-induced perfusion defects, only changes of T apex-T offset (aT-eT) interval in Frank leads and changes of maximum negative potential value of aT-eT integral maps significantly differed from those of normal subjects

  7. Plasma facing surface composition during NSTX Li experiments

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, C.H., E-mail: cskinner@pppl.gov [Princeton Plasma Physics Laboratory, POB 451, Princeton, NJ 08543 (United States); Sullenberger, R. [Department of Mechanical and Aerospace Engineering, Princeton University, NJ 08540 (United States); Koel, B.E. [Department of Chemical and Biological Engineering, Princeton University, NJ 08540 (United States); Jaworski, M.A.; Kugel, H.W. [Princeton Plasma Physics Laboratory, POB 451, Princeton, NJ 08543 (United States)

    2013-07-15

    Lithium conditioned plasma facing surfaces have lowered recycling and enhanced plasma performance on many fusion devices. However, the nature of the plasma–lithium surface interaction has been obscured by the difficulty of in-tokamak surface analysis. We report laboratory studies of the chemical composition of lithium surfaces exposed to typical residual gases found in tokamaks. Solid lithium and a molybdenum alloy (TZM) coated with lithium have been examined using X-ray photoelectron spectroscopy, temperature programmed desorption, and Auger electron spectroscopy both in ultrahigh vacuum conditions and after exposure to trace gases. Lithium surfaces near room temperature were oxidized after exposure to 1–2 Langmuirs of oxygen or water vapor. The oxidation rate by carbon monoxide was four times less. Lithiated PFC surfaces in tokamaks will be oxidized in about 100 s depending on the tokamak vacuum conditions.

  8. The Venus Emissivity Mapper - gaining a global perspective on the surface composition of Venus

    Science.gov (United States)

    Helbert, Joern; Dyar, Melinda; Widemann, Thomas; Marcq, Emmanuel; Maturilli, Alessandro; Mueller, Nils; Kappel, David; Ferrari, Sabrina; D'Amore, Mario; Tsang, Constantine; Arnold, Gabriele; Smrekar, Suzanne; VEM Team

    2017-10-01

    The permanent cloud cover of Venus prohibits observations of the surface with traditional imaging techniques over much of the EM spectral range, leading to the false notion that information about the composition of Venus’ surface could only be derived from lander missions. However, harsh environmental conditions on the surface cause landed missions to be sole site, highly complex, and riskier than orbiting missions.It is now known that 5 transparency windows occur in the Venus atmosphere, ranging from 0.86 µm to 1.18 µm. Recent advances in high temperature laboratory spectroscopy at the PSL at DLR these windows are highly diagnostic for surface mineralogy. Mapping of the southern hemisphere of Venus with VIRTIS on VEX in the 1.02 µm band was a proof-of-concept for an orbital remote sensing approach to surface composition and weathering studies[1-3]. The Venus Emissivity Mapper [4] proposed for the NASA’s Venus Origins Explorer (VOX) and the ESA EnVision proposal builds on these recent advances. It is the first flight instrument specially designed with a sole focus on mapping the surface of Venus using the narrow atmospheric windows around 1 µm. Operating in situ from Venus orbit, VEM will provide a global map of surface composition as well as redox state of the surface, providing a comprehensive picture of surface-atmosphere interaction and support for landing site selection. Continuous observation of the thermal emission of the Venus will provide tight constraints on the current day volcanic activity[5]. This is complemented by measurements of atmospheric water vapor abundance as well as cloud microphysics and dynamics. These data will allow for accurate correction of atmospheric interference on the surface measurements, which provide highly valuable science on their own. A mission combining VEM with a high-resolution radar mapper such as VOX or EnVision in a low circular orbit will provide key insights into the divergent evolution of Venus.1. Smrekar, S

  9. Nanoscale Surface Photovoltage Mapping of 2D Materials and Heterostructures by Illuminated Kelvin Probe Force Microscopy

    KAUST Repository

    Shearer, Melinda J.

    2018-02-01

    Nanomaterials are interesting for a variety of applications, such as optoelectronics and photovoltaics. However, they often have spatial heterogeneity, i.e. composition change or physical change in the topography or structure, which can lead to varying properties that would influence their applications. New techniques must be developed to understand and correlate spatial heterogeneity with changes in electronic properties. Here we highlight the technique of surface photovoltage-Kelvin probe force microscopy (SPV-KFM), which is a modified version of non-contact atomic force microscopy capable of imaging not only the topography and surface potential, but also the surface photovoltage on the nanoscale. We demonstrate its utility in probing monolayer WSe2-MoS2 lateral heterostructures, which form an ultrathin p-n junction promising for photovoltaic and optoelectronic applications. We show surface photovoltage maps highlighting the different photoresponse of the two material regions as a result of the effective charge separation across this junction. Additionally, we study the variations between different heterostructure flakes and emphasize the importance of controlling the synthesis and transfer of these materials to obtain consistent properties and measurements.

  10. Nanoscale Surface Photovoltage Mapping of 2D Materials and Heterostructures by Illuminated Kelvin Probe Force Microscopy

    KAUST Repository

    Shearer, Melinda J.; Li, Ming-yang; Li, Lain-Jong; Jin, Song; Hamers, Robert J

    2018-01-01

    Nanomaterials are interesting for a variety of applications, such as optoelectronics and photovoltaics. However, they often have spatial heterogeneity, i.e. composition change or physical change in the topography or structure, which can lead to varying properties that would influence their applications. New techniques must be developed to understand and correlate spatial heterogeneity with changes in electronic properties. Here we highlight the technique of surface photovoltage-Kelvin probe force microscopy (SPV-KFM), which is a modified version of non-contact atomic force microscopy capable of imaging not only the topography and surface potential, but also the surface photovoltage on the nanoscale. We demonstrate its utility in probing monolayer WSe2-MoS2 lateral heterostructures, which form an ultrathin p-n junction promising for photovoltaic and optoelectronic applications. We show surface photovoltage maps highlighting the different photoresponse of the two material regions as a result of the effective charge separation across this junction. Additionally, we study the variations between different heterostructure flakes and emphasize the importance of controlling the synthesis and transfer of these materials to obtain consistent properties and measurements.

  11. Composite sampling of a Bacillus anthracis surrogate with cellulose sponge surface samplers from a nonporous surface.

    Directory of Open Access Journals (Sweden)

    Jenia A M Tufts

    Full Text Available A series of experiments was conducted to explore the utility of composite-based collection of surface samples for the detection of a Bacillus anthracis surrogate using cellulose sponge samplers on a nonporous stainless steel surface. Two composite-based collection approaches were evaluated over a surface area of 3716 cm2 (four separate 929 cm2 areas, larger than the 645 cm2 prescribed by the standard Centers for Disease Control (CDC and Prevention cellulose sponge sampling protocol for use on nonporous surfaces. The CDC method was also compared to a modified protocol where only one surface of the sponge sampler was used for each of the four areas composited. Differences in collection efficiency compared to positive controls and the potential for contaminant transfer for each protocol were assessed. The impact of the loss of wetting buffer from the sponge sampler onto additional surface areas sampled was evaluated. Statistical tests of the results using ANOVA indicate that the collection of composite samples using the modified sampling protocol is comparable to the collection of composite samples using the standard CDC protocol (p  =  0.261. Most of the surface-bound spores are collected on the first sampling pass, suggesting that multiple passes with the sponge sampler over the same surface may be unnecessary. The effect of moisture loss from the sponge sampler on collection efficiency was not significant (p  =  0.720 for both methods. Contaminant transfer occurs with both sampling protocols, but the magnitude of transfer is significantly greater when using the standard protocol than when the modified protocol is used (p<0.001. The results of this study suggest that composite surface sampling, by either method presented here, could successfully be used to increase the surface area sampled per sponge sampler, resulting in reduced sampling times in the field and decreased laboratory processing cost and turn-around times.

  12. Analysis of surface hardness of artificially aged resin composites

    Directory of Open Access Journals (Sweden)

    Denise Cremonezzi Tornavoi

    2012-02-01

    Full Text Available This study evaluated the effect of artificially accelerated aging (AAA on the surface hardness of eight composite resins: Filtek Z250, Filtek Supreme, 4 Seasons, Herculite, P60, Tetric Ceram, Charisma, and Filtek Z100. Sixteen specimens were made from the test piece of each material, using an 8.0 × 2.0 mm teflon matrix. After 24 hours, eight specimens from each material were submitted to three surface hardness readings using a Shimadzu Microhardness Tester for 5 seconds at a load of 50 gf. The other eight specimens remained in the artificially accelerated aging machine for 382 hours and were submitted to the same surface hardness analysis. The means of each test specimen were submitted to the Kolmogorov-Smirnov test (p > 0.05, ANOVA and Tukey test (p < 0.05. With regard to hardness (F = 86.74, p < 0.0001 the analysis showed significant differences among the resin composite brands. But aging did not influence the hardness of any of the resin composites (F = 0.39, p = 0.53. In this study, there was interaction between the resin composite brand and the aging factors (F = 4.51, p < 0.0002. It was concluded that notwithstanding the type of resin, AAA did not influence surface hardness. However, with regard to hardness there was a significant difference among the resin brands.

  13. Influence of Ear Surface Area on Heat Tolerance of Composite ...

    African Journals Online (AJOL)

    Relative importance of ear surface area on heat tolerance of composite rabbit population was evaluated. The study was conducted during the dry and rainy seasons, climatic data were recorded to obtain categorical heat stress index. Physiological parameters, growth performance, ear length and ear width of the rabbits ...

  14. Phase spectral composition of wind generated ocean surface waves

    Digital Repository Service at National Institute of Oceanography (India)

    Varkey, M.J.

    A study of the composition of the phase spectra of wind generated ocean surface waves is carried out using wave records collected employing a ship borne wave recorder. It is found that the raw phase spectral estimates could be fitted by the Uniform...

  15. A facile method to compare EFTEM maps obtained from materials changing composition over time

    KAUST Repository

    Casu, Alberto

    2015-10-31

    Energy Filtered Transmission Electron Microscopy (EFTEM) is an analytical tool that has been successfully and widely employed in the last two decades for obtaining fast elemental maps in TEM mode. Several studies and efforts have been addressed to investigate limitations and advantages of such technique, as well as to improve the spatial resolution of compositional maps. Usually, EFTEM maps undergo post-acquisition treatments by changing brightness and contrast levels, either via dedicated software or via human elaboration, in order to maximize their signal-to-noise ratio and render them as visible as possible. However, elemental maps forming a single set of EFTEM images are usually subjected to independent map-by-map image treatment. This post-acquisition step becomes crucial when analyzing materials that change composition over time as a consequence of an external stimulus, because the map-by-map approach doesn\\'t take into account how the chemical features of the imaged materials actually progress, in particular when the investigated elements exhibit very low signals. In this article, we present a facile procedure applicable to whole sets of EFTEM maps acquired on a sample that is evolving over time. The main aim is to find a common method to treat the images features, in order to make them as comparable as possible without affecting the information there contained. Microsc. Res. Tech. 78:1090–1097, 2015. © 2015 Wiley Periodicals, Inc.

  16. A facile method to compare EFTEM maps obtained from materials changing composition over time

    KAUST Repository

    Casu, Alberto; Genovese, Alessandro; Di Benedetto, Cristiano; Lentijo Mozo, Sergio; Sogne, Elisa; Zuddas, Efisio; Falqui, Andrea

    2015-01-01

    Energy Filtered Transmission Electron Microscopy (EFTEM) is an analytical tool that has been successfully and widely employed in the last two decades for obtaining fast elemental maps in TEM mode. Several studies and efforts have been addressed to investigate limitations and advantages of such technique, as well as to improve the spatial resolution of compositional maps. Usually, EFTEM maps undergo post-acquisition treatments by changing brightness and contrast levels, either via dedicated software or via human elaboration, in order to maximize their signal-to-noise ratio and render them as visible as possible. However, elemental maps forming a single set of EFTEM images are usually subjected to independent map-by-map image treatment. This post-acquisition step becomes crucial when analyzing materials that change composition over time as a consequence of an external stimulus, because the map-by-map approach doesn't take into account how the chemical features of the imaged materials actually progress, in particular when the investigated elements exhibit very low signals. In this article, we present a facile procedure applicable to whole sets of EFTEM maps acquired on a sample that is evolving over time. The main aim is to find a common method to treat the images features, in order to make them as comparable as possible without affecting the information there contained. Microsc. Res. Tech. 78:1090–1097, 2015. © 2015 Wiley Periodicals, Inc.

  17. Mapping the global depth to bedrock for land surface modelling

    Science.gov (United States)

    Shangguan, W.; Hengl, T.; Yuan, H.; Dai, Y. J.; Zhang, S.

    2017-12-01

    Depth to bedrock serves as the lower boundary of land surface models, which controls hydrologic and biogeochemical processes. This paper presents a framework for global estimation of Depth to bedrock (DTB). Observations were extracted from a global compilation of soil profile data (ca. 130,000 locations) and borehole data (ca. 1.6 million locations). Additional pseudo-observations generated by expert knowledge were added to fill in large sampling gaps. The model training points were then overlaid on a stack of 155 covariates including DEM-based hydrological and morphological derivatives, lithologic units, MODIS surfacee reflectance bands and vegetation indices derived from the MODIS land products. Global spatial prediction models were developed using random forests and Gradient Boosting Tree algorithms. The final predictions were generated at the spatial resolution of 250m as an ensemble prediction of the two independently fitted models. The 10-fold cross-validation shows that the models explain 59% for absolute DTB and 34% for censored DTB (depths deep than 200 cm are predicted as 200 cm). The model for occurrence of R horizon (bedrock) within 200 cm does a good job. Visual comparisons of predictions in the study areas where more detailed maps of depth to bedrock exist show that there is a general match with spatial patterns from similar local studies. Limitation of the data set and extrapolation in data spare areas should not be ignored in applications. To improve accuracy of spatial prediction, more borehole drilling logs will need to be added to supplement the existing training points in under-represented areas.

  18. Raman mapping of intact biofilms on stainless steel surfaces

    Science.gov (United States)

    Each slide under the Raman Microscope was mapped for approximately 18.5 hours with a dimension of 36x36 that provides a greater result compared to doing a smaller dimension scan. The results from the Raman Mapping show the location and position of how the bacteria are growing scattered or straight a...

  19. Method for Pre-Conditioning a Measured Surface Height Map for Model Validation

    Science.gov (United States)

    Sidick, Erkin

    2012-01-01

    This software allows one to up-sample or down-sample a measured surface map for model validation, not only without introducing any re-sampling errors, but also eliminating the existing measurement noise and measurement errors. Because the re-sampling of a surface map is accomplished based on the analytical expressions of Zernike-polynomials and a power spectral density model, such re-sampling does not introduce any aliasing and interpolation errors as is done by the conventional interpolation and FFT-based (fast-Fourier-transform-based) spatial-filtering method. Also, this new method automatically eliminates the measurement noise and other measurement errors such as artificial discontinuity. The developmental cycle of an optical system, such as a space telescope, includes, but is not limited to, the following two steps: (1) deriving requirements or specs on the optical quality of individual optics before they are fabricated through optical modeling and simulations, and (2) validating the optical model using the measured surface height maps after all optics are fabricated. There are a number of computational issues related to model validation, one of which is the "pre-conditioning" or pre-processing of the measured surface maps before using them in a model validation software tool. This software addresses the following issues: (1) up- or down-sampling a measured surface map to match it with the gridded data format of a model validation tool, and (2) eliminating the surface measurement noise or measurement errors such that the resulted surface height map is continuous or smoothly-varying. So far, the preferred method used for re-sampling a surface map is two-dimensional interpolation. The main problem of this method is that the same pixel can take different values when the method of interpolation is changed among the different methods such as the "nearest," "linear," "cubic," and "spline" fitting in Matlab. The conventional, FFT-based spatial filtering method used to

  20. Venus surface peeking through the atmosphere - gaining a global perspective on the surface composition through near infrared observations

    Science.gov (United States)

    Helbert, J.; Dyar, M. D.; Maturilli, A.; D'Amore, M.; Ferrari, S.; Mueller, N. T.; Smrekar, S. E.

    2017-12-01

    Venus is the most Earth-like of the terrestrial planets, though very little is known about its surface composition. Thanks to recent advances in laboratory spectroscopy and spectral analysis techniques, this is about to change. Although the atmosphere prohibits observations of the surface with traditional imaging techniques over much of the EM spectral range, five transparent windows between 0.86 µm and 1.18 µm occur in the atmosphere's CO2 spectrum. New high temperature laboratory spectra from the Planetary Spectroscopy Laboratory at DLR show that spectra in these windows are highly diagnostic for surface mineralogy [1]. The Venus Emissivity Mapper (VEM) [2] builds on these recent advances. It is proposed for NASA's Venus Origins Explorer where a radar will provided the needed high-resolution altimetry and ESA's EnVision would provide stereo topography instead. VEM is the first flight instrument specially designed to focus solely on mapping Venus' surface using the windows around 1 µm. Operating in situ from Venus orbit, VEM will provide a global map of composition as well as redox state of the surface, enabling a comprehensive picture of surface-atmosphere interaction on Venus. VEM will return a complex data set containing surface, atmospheric, cloud, and scattering information. Total planned data volume for a typical mission scenario exceeds 1TB. Classical analysis techniques have been successfully used for VIRTIS on Venus Express [3-5] and could be employed with the VEM data. However, application of machine learning approaches to this rich dataset is vastly more efficient, as has already been confirmed with laboratory data. Binary classifiers [6] demonstrate that at current best estimate errors, basalt spectra are confidently discriminated from basaltic andesites, andesites, and rhyolite/granite. Applying the approach of self-organizing maps to the increasingly large set of laboratory measurements allows searching for additional mineralogical indicators

  1. Mapping Surface Heat Fluxes by Assimilating SMAP Soil Moisture and GOES Land Surface Temperature Data

    Science.gov (United States)

    Lu, Yang; Steele-Dunne, Susan C.; Farhadi, Leila; van de Giesen, Nick

    2017-12-01

    Surface heat fluxes play a crucial role in the surface energy and water balance. In situ measurements are costly and difficult, and large-scale flux mapping is hindered by surface heterogeneity. Previous studies have demonstrated that surface heat fluxes can be estimated by assimilating land surface temperature (LST) and soil moisture to determine two key parameters: a neutral bulk heat transfer coefficient (CHN) and an evaporative fraction (EF). Here a methodology is proposed to estimate surface heat fluxes by assimilating Soil Moisture Active Passive (SMAP) soil moisture data and Geostationary Operational Environmental Satellite (GOES) LST data into a dual-source (DS) model using a hybrid particle assimilation strategy. SMAP soil moisture data are assimilated using a particle filter (PF), and GOES LST data are assimilated using an adaptive particle batch smoother (APBS) to account for the large gap in the spatial and temporal resolution. The methodology is implemented in an area in the U.S. Southern Great Plains. Assessment against in situ observations suggests that soil moisture and LST estimates are in better agreement with observations after assimilation. The RMSD for 30 min (daytime) flux estimates is reduced by 6.3% (8.7%) and 31.6% (37%) for H and LE on average. Comparison against a LST-only and a soil moisture-only assimilation case suggests that despite the coarse resolution, assimilating SMAP soil moisture data is not only beneficial but also crucial for successful and robust flux estimation, particularly when the uncertainties in the model estimates are large.

  2. Surface discoloration of composite resins: Effects of staining and bleaching.

    Science.gov (United States)

    Poggio, Claudio; Beltrami, Riccardo; Scribante, Andrea; Colombo, Marco; Chiesa, Marco

    2012-09-01

    The purpose of this in vitro study was to evaluate surface discoloration of three microhybrid composite resins (Esthet•X HD, Clearfil AP-X, Gradia Direct) and five nanohybrid composite resins (Ceram•X, GC Kalore, G-aenial, Grandio, GrandioSO), after staining and bleaching procedures. The composite resins were polymerized with a curing light (Celalux II, Voco, Cuxhaven, Germany) into 160 silicon molds (6,4 mm in diameter and 2 mm in thickness) to obtain identical specimens. Twenty samples for each composite resin were prepared. The specimens were polished using an automated polishing machine with the sequence of 600-, 800-, 1000-grit abrasive paper under water irrigation. The specimens were immersed in tea and distilled water: the specimens were dipped for 20 min, once a day (every 24 h), for 14 days into the drinks. The specimens were then bleached with carbamide peroxide at 17% (Perfect Bleach-Voco). The color of specimens was measured with a spectrophotometer according to the CIE L(*)a(*)b(*) system after light-polymerization of composite resin specimens, after 7 days, after 14 days, and after bleaching. The color difference h index (DEab(*)) between each measurement was calculated. Statistical analysis was made using analysis of variance (ANOVA). All specimens showed a significant increase in staining with a similar trend and no significant differences between microhybrid and nanohybrid composite resins. After whitening procedures, materials tested showed both significant and unsignificant differences of the h index. Microhybrid and nanohybrid composite resins had similar in vitro surface discoloration in tea. After bleaching, discoloration was removed from some composite resins tested.

  3. Elastic representation surfaces of unidirectional graphite/epoxy composites

    International Nuclear Information System (INIS)

    Kriz, R.D.; Ledbetter, H.M.

    1985-01-01

    Unidirectional graphite/epoxy composites exhibit high elastic anisotropy and unusual geometrical features in their elastic-property polar diagrams. From the five-component transverse-isotropic elastic-stiffness tensor we compute and display representation surfaces for Young's modulus, torsional modulus, linear compressibility, and Poisson's ratios. Based on Christoffel-equation solutions, we describe some unusual elastic-wave-surface topological features. Musgrave considered in detail the differences between phase-velocity and group-velocity surfaces arising from high elastic anisotropy. For these composites, we find effects similar to, but more dramatic than, Musgrave's. Some new, unexpected results for graphite/epoxy include: a shear-wave velocity that exceeds a longitudinal velocity in the plane transverse to the fiber; a wave that changes polarization character from longitudinal to transverse as the propagation direction sweeps from the fiber axis to the perpendicular axis

  4. Analytical Retrieval of Global Land Surface Emissivity Maps at AMSR-E passive microwave frequencies

    Science.gov (United States)

    Norouzi, H.; Temimi, M.; Khanbilvardi, R.

    2009-12-01

    Land emissivity is a crucial boundary condition in Numerical Weather Prediction (NWP) modeling. Land emissivity is also a key indicator of land surface and subsurface properties. The objective of this study, supported by NOAA-NESDIS, is to develop global land emissivity maps using AMSR-E passive microwave measurements along with several ancillary data. The International Satellite Cloud Climatology Project (ISCCP) database has been used to obtain several inputs for the proposed approach such as land surface temperature, cloud mask and atmosphere profile. The Community Radiative Transfer Model (CRTM) has been used to estimate upwelling and downwelling atmospheric contributions. Although it is well known that correction of the atmospheric effect on brightness temperature is required at higher frequencies (over 19 GHz), our preliminary results have shown that a correction at 10.7 GHz is also necessary over specific areas. The proposed approach is based on three main steps. First, all necessary data have been collected and processed. Second, a global cloud free composite of AMSR-E data and corresponding ancillary images is created. Finally, monthly composting of emissivity maps has been performed. AMSR-E frequencies at 6.9, 10.7, 18.7, 36.5 and 89.0 GHz have been used to retrieve the emissivity. Water vapor information obtained from ISCCP (TOVS data) was used to calculate upwelling, downwelling temperatures and atmospheric transmission in order to assess the consistency of those derived from the CRTM model. The frequent land surface temperature (LST) determination (8 times a day) in the ISCCP database has allowed us to assess the diurnal cycle effect on emissivity retrieval. Differences in magnitude and phase between thermal temperature and low frequencies microwave brightness temperature have been noticed. These differences seem to vary in space and time. They also depend on soil texture and thermal inertia. The proposed methodology accounts for these factors and

  5. Optimization of microwave-assisted extraction (MAP) for ginseng components by response surface methodology.

    Science.gov (United States)

    Kwon, Joong-Ho; Bélanger, Jacqueline M R; Paré, J R Jocelyn

    2003-03-26

    Response surface methodology (RSM) was applied to predict optimum conditions for microwave-assisted extraction-a MAP technology-of saponin components from ginseng roots. A central composite design was used to monitor the effect of ethanol concentration (30-90%, X(1)) and extraction time (30-270 s, X(2)) on dependent variables, such as total extract yield (Y(1)), crude saponin content (Y(2)), and saponin ratio (Y(3)), under atmospheric pressure conditions when focused microwaves were applied at an emission frequency of 2450 MHz. In MAP under pre-established conditions, correlation coefficients (R (2)) of the models for total extract yield and crude saponin were 0.9841 (p extraction conditions were predicted for each variable as 52.6% ethanol and 224.7 s in extract yield and as 77.3% ethanol and 295.1 s in crude saponins, respectively. Estimated maximum values at predicted optimum conditions were in good agreement with experimental values.

  6. Compositional cokriging for mapping the probability risk of groundwater contamination by nitrates.

    Science.gov (United States)

    Pardo-Igúzquiza, Eulogio; Chica-Olmo, Mario; Luque-Espinar, Juan A; Rodríguez-Galiano, Víctor

    2015-11-01

    Contamination by nitrates is an important cause of groundwater pollution and represents a potential risk to human health. Management decisions must be made using probability maps that assess the nitrate concentration potential of exceeding regulatory thresholds. However these maps are obtained with only a small number of sparse monitoring locations where the nitrate concentrations have been measured. It is therefore of great interest to have an efficient methodology for obtaining those probability maps. In this paper, we make use of the fact that the discrete probability density function is a compositional variable. The spatial discrete probability density function is estimated by compositional cokriging. There are several advantages in using this approach: (i) problems of classical indicator cokriging, like estimates outside the interval (0,1) and order relations, are avoided; (ii) secondary variables (e.g. aquifer parameters) can be included in the estimation of the probability maps; (iii) uncertainty maps of the probability maps can be obtained; (iv) finally there are modelling advantages because the variograms and cross-variograms of real variables that do not have the restrictions of indicator variograms and indicator cross-variograms. The methodology was applied to the Vega de Granada aquifer in Southern Spain and the advantages of the compositional cokriging approach were demonstrated. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Mapping surrogate gasoline compositions into RON/MON space

    NARCIS (Netherlands)

    Morgan, N.; Smallbone, A.; Bhave, A.; Kraft, M.; Cracknell, R.; Kalghatgi, G.T.

    2010-01-01

    In this paper, new experimentally determined octane numbers (RON and MON) of blends of a tri-component surrogate consisting of toluene, n-heptane, i-octane (called toluene reference fuel TRF) arranged in an augmented simplex design are used to derive a simple response surface model for the octane

  8. Investigation of sizing - from glass fibre surface to composite interface

    DEFF Research Database (Denmark)

    Petersen, Helga Nørgaard; Kusano, Yukihiro

    significantly. The usage span wide, from furniture and car components to construction materials. Even though, the concept of composites is well known and widely applied, the fundamental principles of the interaction of the constituents, in the composites are still not fully understood. This thesis is a part...... of the sizing from the glass fibre surface to the interface in composites. Through soxhlet extraction with acetone it was possible to remove a part of the sizing from the glass fibres for analysis. By burning off the sizing at 565 ºC a higher mass loss was obtained than from the extraction, indicating...... increased after the removal of sizing by extraction but also when the sizing was removed by burning. This could partly be explained by the sizing being less dense than the glass fibres. For the burned glass fibres compactment of the glass structure also yields an increase in stiffness. The fibre strength...

  9. Phase Composition Maps integrate mineral compositions with rock textures from the micro-meter to the thin section scale

    Science.gov (United States)

    Willis, Kyle V.; Srogi, LeeAnn; Lutz, Tim; Monson, Frederick C.; Pollock, Meagen

    2017-12-01

    Textures and compositions are critical information for interpreting rock formation. Existing methods to integrate both types of information favor high-resolution images of mineral compositions over small areas or low-resolution images of larger areas for phase identification. The method in this paper produces images of individual phases in which textural and compositional details are resolved over three orders of magnitude, from tens of micrometers to tens of millimeters. To construct these images, called Phase Composition Maps (PCMs), we make use of the resolution in backscattered electron (BSE) images and calibrate the gray scale values with mineral analyses by energy-dispersive X-ray spectrometry (EDS). The resulting images show the area of a standard thin section (roughly 40 mm × 20 mm) with spatial resolution as good as 3.5 μm/pixel, or more than 81 000 pixels/mm2, comparable to the resolution of X-ray element maps produced by wavelength-dispersive spectrometry (WDS). Procedures to create PCMs for mafic igneous rocks with multivariate linear regression models for minerals with solid solution (olivine, plagioclase feldspar, and pyroxenes) are presented and are applicable to other rock types. PCMs are processed using threshold functions based on the regression models to image specific composition ranges of minerals. PCMs are constructed using widely-available instrumentation: a scanning-electron microscope (SEM) with BSE and EDS X-ray detectors and standard image processing software such as ImageJ and Adobe Photoshop. Three brief applications illustrate the use of PCMs as petrologic tools: to reveal mineral composition patterns at multiple scales; to generate crystal size distributions for intracrystalline compositional zones and compare growth over time; and to image spatial distributions of minerals at different stages of magma crystallization by integrating textures and compositions with thermodynamic modeling.

  10. System and technique for retrieving depth information about a surface by projecting a composite image of modulated light patterns

    Science.gov (United States)

    Hassebrook, Laurence G. (Inventor); Lau, Daniel L. (Inventor); Guan, Chun (Inventor)

    2010-01-01

    A technique, associated system and program code, for retrieving depth information about at least one surface of an object, such as an anatomical feature. Core features include: projecting a composite image comprising a plurality of modulated structured light patterns, at the anatomical feature; capturing an image reflected from the surface; and recovering pattern information from the reflected image, for each of the modulated structured light patterns. Pattern information is preferably recovered for each modulated structured light pattern used to create the composite, by performing a demodulation of the reflected image. Reconstruction of the surface can be accomplished by using depth information from the recovered patterns to produce a depth map/mapping thereof. Each signal waveform used for the modulation of a respective structured light pattern, is distinct from each of the other signal waveforms used for the modulation of other structured light patterns of a composite image; these signal waveforms may be selected from suitable types in any combination of distinct signal waveforms, provided the waveforms used are uncorrelated with respect to each other. The depth map/mapping to be utilized in a host of applications, for example: displaying a 3-D view of the object; virtual reality user-interaction interface with a computerized device; face--or other animal feature or inanimate object--recognition and comparison techniques for security or identification purposes; and 3-D video teleconferencing/telecollaboration.

  11. Kenaf-polypropylene composites: effect of amphiphilic coupling agent on surface properties of fibres and composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2010-10-01

    Full Text Available This paper presents an experimental study on the use of zein as a coupling agent in natural fibre composites. Kenaf nonwovens were treated with zein coupling agent, which is a protein extracted from corn. The surface characteristics of untreated...

  12. Pure Surface Texture Mapping Technology and it's Application for Mirror Image

    Directory of Open Access Journals (Sweden)

    Wei Feng Wang

    2013-02-01

    Full Text Available Based on the study of pure surface texture mapping technology, pure texture surface rendering method is proposed. The method is combined pure surface texture rendering and view mirror, real-time rendering has an index of refraction, reflection, and the flow of water ripple effect. Through the experimental verification of the validity of the algorithm.

  13. Calibration and Industrial Application of Instrument for Surface Mapping based on AFM

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Kofod, Niels; De Chiffre, Leonardo

    2002-01-01

    The paper describes the calibration and application of an integrated system for topographic characterisation of fine surfaces on large workpieces. The system, consisting of an atomic force microscope mounted on a coordinate measuring machine, was especially designed for surface mapping, i.e., mea...... consisting of a steel sphere with a polished surface having 3 nm roughness....

  14. Surface Geophysical Measurements for Locating and Mapping Ice-Wedges

    DEFF Research Database (Denmark)

    Ingeman-Nielsen, Thomas; Tomaskovicova, Sonia; Larsen, S.H.

    2012-01-01

    to test the applicability of DC electrical resistivity tomography (ERT) and Ground Penetrating Radar (GPR) to identifying and mapping ice-wedge occurrences. The site is located in Central West Greenland, and the ice-wedges are found in a permafrozen peat soil with an active layer of about 30 cm. ERT...

  15. Bioactive carbon-PEEK composites prepared by chemical surface treatment.

    Science.gov (United States)

    Miyazaki, Toshiki; Matsunami, Chisato; Shirosaki, Yuki

    2017-01-01

    Polyetheretherketone (PEEK) has attracted much attention as an artificial intervertebral spacer for spinal reconstruction. Furthermore, PEEK plastic reinforced with carbon fiber has twice the bending strength of pure PEEK. However, the PEEK-based materials do not show ability for direct bone bonding, i.e., bioactivity. Although several trials have been conducted for enabling PEEK with bioactivity, few studies have reported on bioactive surface modification of carbon-PEEK composites. In the present study, we attempted the preparation of bioactive carbon-PEEK composites by chemical treatments with H 2 SO 4 and CaCl 2 . Bioactivity was evaluated by in vitro apatite formation in simulated body fluid (SBF). The apatite formation on the carbon-PEEK composite was compared with that of pure PEEK. Both pure PEEK and carbon-PEEK composite formed the apatite in SBF when they were treated with H 2 SO 4 and CaCl 2 ; the latter showed higher apatite-forming ability than the former. It is conjectured that many functional groups able to induce the apatite nucleation, such as sulfo and carboxyl groups, are incorporated into the dispersed carbon phase in the carbon-PEEK composites. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Organic matter composition of soil macropore surfaces under different agricultural management practices

    Science.gov (United States)

    Glæsner, Nadia; Leue, Marin; Magid, Jacob; Gerke, Horst H.

    2016-04-01

    Understanding the heterogeneous nature of soil, i.e. properties and processes occurring specifically at local scales is essential for best managing our soil resources for agricultural production. Examination of intact soil structures in order to obtain an increased understanding of how soil systems operate from small to large scale represents a large gap within soil science research. Dissolved chemicals, nutrients and particles are transported through the disturbed plow layer of agricultural soil, where after flow through the lower soil layers occur by preferential flow via macropores. Rapid movement of water through macropores limit the contact between the preferentially moving water and the surrounding soil matrix, therefore contact and exchange of solutes in the water is largely restricted to the surface area of the macropores. Organomineral complex coated surfaces control sorption and exchange properties of solutes, as well as availability of essential nutrients to plant roots and to the preferentially flowing water. DRIFT (Diffuse Reflectance infrared Fourier Transform) Mapping has been developed to examine composition of organic matter coated macropores. In this study macropore surfaces structures will be determined for organic matter composition using DRIFT from a long-term field experiment on waste application to agricultural soil (CRUCIAL, close to Copenhagen, Denmark). Parcels with 5 treatments; accelerated household waste, accelerated sewage sludge, accelerated cattle manure, NPK and unfertilized, will be examined in order to study whether agricultural management have an impact on the organic matter composition of intact structures.

  17. Pre-LBA CABARE Mapped Land Surface and Vegetation Characteristics, Rondonia, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface parameter digital maps of vegetation, soil, and topography were obtained for Rondonia, Brazil, covering the 5x5 degree region bounded by 13-8 degrees S and...

  18. Pre-LBA CABARE Mapped Land Surface and Vegetation Characteristics, Rondonia, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Surface parameter digital maps of vegetation, soil, and topography were obtained for Rondonia, Brazil, covering the 5x5 degree region bounded by 13-8...

  19. Piezoelectric composite morphing control surfaces for unmanned aerial vehicles

    Science.gov (United States)

    Ohanian, Osgar J., III; Karni, Etan D.; Olien, Chris C.; Gustafson, Eric A.; Kochersberger, Kevin B.; Gelhausen, Paul A.; Brown, Bridget L.

    2011-04-01

    The authors have explored the use of morphing control surfaces to replace traditional servo-actuated control surfaces in UAV applications. The morphing actuation is accomplished using Macro Fiber Composite (MFC) piezoelectric actuators in a bimorph configuration to deflect the aft section of a control surface cross section. The resulting camber change produces forces and moments for vehicle control. The flexible piezoelectric actuators are damage tolerant and provide excellent bandwidth. The large amplitude morphing deflections attained in bench-top experiments demonstrate the potential for excellent control authority. Aerodynamic performance calculations using experimentally measured morphed geometries indicate changes in sectional lift coefficients that are superior to a servo-actuated hinged flap airfoil. This morphing flight control actuation technology could eliminate the need for servos and mechanical linkages in small UAVs and thereby increase reliability and reduce drag.

  20. Isointegral analysis of body surface maps for the assessment of location and size of myocardial infarction

    International Nuclear Information System (INIS)

    Tonooka, I.; Kubota, I.; Watanabe, Y.; Tsuiki, K.; Yasui, S.

    1983-01-01

    To estimate the location and size of myocardial infarction (MI), an isointegral mapping technique was adopted from among various body surface electrocardiographic mapping techniques. QRS isointegral and departure maps were made in 35 patients with MI. These patients were separated into 3 groups, based on the location of MI: anterior, inferior, and anterior plus inferior. The severity and location of MI were estimated by thallium-201 myocardial perfusion imaging and the degree of scintigraphic defect was represented by a defect score. The extent of MI was expected to be reflected on the QRS isointegral maps as a distribution of negative QRS complex time-integral values. However, the extent and the location of MI were hardly detectable by the original maps. A departure mapping technique was then devised to observe the distribution of departure index on the body surface. Particular attention was given to the area where the departure index was less than -2, and this area was expected to reflect the location and size of specific abnormality of isointegral map due to MI. There were strong correlations between departure area and defect score in the anterior and inferior MI cases (r . 0.88 and r . 0.79, respectively). However, patients with anterior MI plus inferior MI showed no such correlation. Q-wave mapping was compared with QRS isointegral mapping, and QRS isointegral mapping was found to be more accurate in the estimation of the location and size of MI than Q wave mapping. Thus, QRS isointegral mapping, especially departure mapping, is more useful and convenient for detecting the location and size of MI than methods such as isopotential and Q wave mapping

  1. Ray-map migration of transmitted surface waves

    KAUST Repository

    Li, Jing; Schuster, Gerard T.

    2016-01-01

    Near-surface normal faults can sometimes separate two distinct zones of velocity heterogeneity, where the medium on one side of the fault has a faster velocity than on the other side. Therefore, the slope of surface-wave arrivals in a common

  2. Surface kinetic temperature mapping using satellite spectral data in ...

    African Journals Online (AJOL)

    The result revealed that despite the limited topographic differences of the rift lakes and their proximity, the surface kinetic temperature difference is high, mainly due to groundwater and surface water fluxes. From thermal signature analysis two hot springs below the lake bed of Ziway were discovered. The various hot springs ...

  3. The control mechanism of surface traps on surface charge behavior in alumina-filled epoxy composites

    International Nuclear Information System (INIS)

    Li, Chuanyang; Hu, Jun; Lin, Chuanjie; He, Jinliang

    2016-01-01

    To investigate the role surface traps play in the charge injection and transfer behavior of alumina-filled epoxy composites, surface traps with different trap levels are introduced by different surface modification methods which include dielectric barrier discharges plasma, direct fluorination, and Cr 2 O 3 coating. The resulting surface physicochemical characteristics of experimental samples were observed using atomic force microscopy, scanning electron microscopy and fourier transform infrared spectroscopy. The surface potential under dc voltage was detected and the trap level distribution was measured. The results suggest that the surface morphology of the experimental samples differs dramatically after treatment with different surface modification methods. Different surface trap distributions directly determine the charge injection and transfer property along the surface. Shallow traps with trap level of 1.03–1.11 eV and 1.06–1.13 eV introduced by plasma and fluorination modifications are conducive for charge transport along the insulating surface, and the surface potential can be modified, producing a smoother potential curve. The Cr 2 O 3 coating can introduce a large number of deep traps with energy levels ranging from 1.09 to 1.15 eV. These can prevent charge injection through the reversed electric field formed by intensive trapped charges in the Cr 2 O 3 coatings. (paper)

  4. Laser Surface Treatment and Modification of Aluminum Alloy Matrix Composites

    Science.gov (United States)

    Abbass, Muna Khethier

    2018-02-01

    The present work aimed to study the laser surface treatment and modification of Al-4.0%Cu-1.0%Mg alloy matrix composite reinforced with 10%SiC particles produced by stir casting. The specimens of the base alloy and composite were irradiated with an Nd:YAG laser of 1000 mJ, 1064 nm and 3 Hz . Dry wear test using the pin-on -disc technique at different sliding times (5-30 min) at a constant applied load and sliding speed were performed before and after laser treatment. Micro hardness and wear resistance were increased for all samples after laser hardening treatment. The improvement of these properties is explained by microstructural homogenization and grain refinement of the laser treated surface. Modification and refinement of SiC particles and grain refinement in the microstructure of the aluminum alloy matrix (α-Al) were observed by optical and SEM micrographs. The highest increase in hardness was 21.4% and 26.2% for the base alloy and composite sample respectively.

  5. Detailed mapping of surface units on Mars with HRSC color data

    Science.gov (United States)

    Combe, J.-Ph.; Wendt, L.; McCord, T. B.; Neukum, G.

    2008-09-01

    phyllosilicates form generally bright outcrops with complex contour lines that allow visual discrimination, even if this bright color is similar to well-illuminated bright red dust. When the surface is spectrally diverse like Marwth Vallis, contrast enhancement may be sufficient to reveal subtle color differences that correspond to different types of materials (Fig. 1a). However, those remain faint color variations as all the bands are highly correlated. Principal Component Analysis (PCA) PCA is a tool for decorrelation and noise removal that maximizes color unit differences. On Marwth Vallis, PCA highlights the diversity of the surface on a spectacular way (Fig. 1b). Those images may be compared to the maps of mineral composition obtained by [11] from spectral analysis imaging spectrometer data. Part of the information in Fig. 1b is likely related to surface roughness because of the complex geometry of observation of the instrument. Furthermore, only an extremely clear atmosphere and low-compressed datasets allow obtaining such sharp results. Consequently, the meaning of the colors varies from image-to-image and is qualitative only. More quantitative and comparable results require spectral analysis, either to remove or to normalize atmospheric and geometric effects. Spectral analysis on HRSC data For this application the surface units to be distinguished have to possess linear independent color vectors in the five-dimensional color space of HRSC data. It has been shown by [2-5] that on the global scale, only four spectral endmembers representing red, iron oxide-rich material, dark, basaltic material, and ice plus a shade component containing effects of observation and illumination geometry, are sufficient to explain most of the colors present in HRSC color imagery. We assess this at our test areas contain a maximum of surface mineralogy diversity by applying refined methods to model (and remove) the shade contribution in order to test if a further surface component can be

  6. Neutron radiography of aircraft composite flight control surfaces

    International Nuclear Information System (INIS)

    Lewis, W.J.; Bennett, L.G.I.; Chalovich, T.R.; Francescone, O.

    2001-01-01

    A small (20 kWth), safe, pool-type nuclear research reactor called the SLOWPOKE-2 is located at the Royal Military College of Canada (RMC). The reactor was originally installed for teaching, training, research and semi-routine analysis, specifically, neutron activation analysis. It was envisioned that the neutrons from the SLOWPOKE-2 could also be used for neutron radiography, and so a research program was initiated to develop this technology. Over a period of approximately 15 years, and through a series of successive modifications, a neutron radiography system (NRS) was developed. Once completed, several applications of the technology have been demonstrated, including the nondestructive examination of the composite flight control surfaces from the Canadian Air Force's primary jet fighter, the CF18 Hornet aircraft. An initial trial was setup to investigate the flight control surfaces of 3 aircraft, to determine the parameters for a final licensed system, and to compare the results to other nondestructive methods. Over 500 neutron radiographs were made for these first 3 aircraft, and moisture and corrosion were discovered in the honeycomb structure and hydration was found in the composite and adhesive layers. In comparison with other NDT methods, neutron radiography was the only method that could detect the small areas of corrosion and moisture entrapment. However, before examining an additional 7 aircraft, the recommended modifications to the NRS were undertaken. These modifications were necessary to accommodate the larger flight control surfaces safely by incorporating flexible conformable shielding. As well, to expedite inspections so that all flight control surfaces from one aircraft could be completed in less than two weeks, there was a need to decrease the exposure time by both faster film/conversion screen combinations and by incorporating the capability of near realtime, digital radioscopy. Finally, as there are no inspection specific image quality

  7. An atlas of the smaller maps in orientable and nonorientable surfaces

    CERN Document Server

    Jackson, David

    2000-01-01

    Maps are beguilingly simple structures with deep and ubiquitous properties. They arise in an essential way in many areas of mathematics and mathematical physics, but require considerable time and computational effort to generate. Few collected drawings are available for reference, and little has been written, in book form, about their enumerative aspects. An Atlas of the Smaller Maps in Orientable and Nonorientable Surfaces is the first book to provide complete collections of maps along with their vertex and face partitions, number of rootings, and an index number for cross referencing. It provides an explanation of axiomatization and encoding, and serves as an introduction to maps as a combinatorial structure. The Atlas lists the maps first by genus and number of edges, and gives the embeddings of all graphs with at most five edges in orientable surfaces, thus presenting the genus distribution for each graph. Exemplifying the use of the Atlas, the authors explore two substantial conjectures with origins in ...

  8. Surface composition of biomedical components by ion beam analysis

    International Nuclear Information System (INIS)

    Kenny, M.J.; Wielunski, L.S.; Baxter, G.R.

    1991-01-01

    Materials used for replacement body parts must satisfy a number of requirements such as biocompatibility and mechanical ability to handle the task with regard to strength, wear and durability. When using a CVD coated carbon fibre reinforced carbon ball, the surface must be ion implanted with uniform dose of nitrogen ions in order to make it wear resistant. The mechanism by which the wear resistance is improved is one of radiation damage and the required dose of about 10 16 cm -2 can have a tolerance of about 20%. To implant a spherical surface requires manipulation of the sample within the beam and control system (either computer or manually operated) to enable uniform dose all the way from polar to equatorial regions on the surface. A manipulator has been designed and built for this purpose. In order to establish whether the dose is uniform, nuclear reaction analysis using the reaction 14 N(d,α) 12 C is an ideal method of profiling. By taking measurements at a number of points on the surface, the uniformity of nitrogen dose can be ascertained. It is concluded that both Rutherford Backscattering and Nuclear Reaction Analysis can be used for rapid analysis of surface composition of carbon based materials used for replacement body components. 2 refs., 2 figs

  9. Functional and structural mapping of human cerebral cortex: solutions are in the surfaces

    Science.gov (United States)

    Van Essen, D. C.; Drury, H. A.; Joshi, S.; Miller, M. I.

    1998-01-01

    The human cerebral cortex is notorious for the depth and irregularity of its convolutions and for its variability from one individual to the next. These complexities of cortical geography have been a chronic impediment to studies of functional specialization in the cortex. In this report, we discuss ways to compensate for the convolutions by using a combination of strategies whose common denominator involves explicit reconstructions of the cortical surface. Surface-based visualization involves reconstructing cortical surfaces and displaying them, along with associated experimental data, in various complementary formats (including three-dimensional native configurations, two-dimensional slices, extensively smoothed surfaces, ellipsoidal representations, and cortical flat maps). Generating these representations for the cortex of the Visible Man leads to a surface-based atlas that has important advantages over conventional stereotaxic atlases as a substrate for displaying and analyzing large amounts of experimental data. We illustrate this by showing the relationship between functionally specialized regions and topographically organized areas in human visual cortex. Surface-based warping allows data to be mapped from individual hemispheres to a surface-based atlas while respecting surface topology, improving registration of identifiable landmarks, and minimizing unwanted distortions. Surface-based warping also can aid in comparisons between species, which we illustrate by warping a macaque flat map to match the shape of a human flat map. Collectively, these approaches will allow more refined analyses of commonalities as well as individual differences in the functional organization of primate cerebral cortex.

  10. Surface mapping via unsupervised classification of remote sensing: application to MESSENGER/MASCS and DAWN/VIRS data.

    Science.gov (United States)

    D'Amore, M.; Le Scaon, R.; Helbert, J.; Maturilli, A.

    2017-12-01

    Machine-learning achieved unprecedented results in high-dimensional data processing tasks with wide applications in various fields. Due to the growing number of complex nonlinear systems that have to be investigated in science and the bare raw size of data nowadays available, ML offers the unique ability to extract knowledge, regardless the specific application field. Examples are image segmentation, supervised/unsupervised/ semi-supervised classification, feature extraction, data dimensionality analysis/reduction.The MASCS instrument has mapped Mercury surface in the 400-1145 nm wavelength range during orbital observations by the MESSENGER spacecraft. We have conducted k-means unsupervised hierarchical clustering to identify and characterize spectral units from MASCS observations. The results display a dichotomy: a polar and equatorial units, possibly linked to compositional differences or weathering due to irradiation. To explore possible relations between composition and spectral behavior, we have compared the spectral provinces with elemental abundance maps derived from MESSENGER's X-Ray Spectrometer (XRS).For the Vesta application on DAWN Visible and infrared spectrometer (VIR) data, we explored several Machine Learning techniques: image segmentation method, stream algorithm and hierarchical clustering.The algorithm successfully separates the Olivine outcrops around two craters on Vesta's surface [1]. New maps summarizing the spectral and chemical signature of the surface could be automatically produced.We conclude that instead of hand digging in data, scientist could choose a subset of algorithms with well known feature (i.e. efficacy on the particular problem, speed, accuracy) and focus their effort in understanding what important characteristic of the groups found in the data mean. [1] E Ammannito et al. "Olivine in an unexpected location on Vesta's surface". In: Nature 504.7478 (2013), pp. 122-125.

  11. Band mapping of surface states vs. adsorbate coverage

    International Nuclear Information System (INIS)

    Rotenberg, E.; Kevan, S.D.; Denlinger, J.D.; Chung, Jin-Wook

    1997-01-01

    The theory of electron bands, which arises from basic quantum mechanical principles, has been the cornerstone of solid state physics for over 60 years. Simply put, an energy band is an electron state in a solid whose energy varies with its momentum (similar to, but with a more complicated dependence than, how a free electron's energy is proportional to its momentum squared). Much attention over the last 15 years has been given to the study of band structure of surfaces and interfaces, especially as the applications of these two-dimensional systems have become increasingly important to industry and science. The ultraESCA endstation at beamline 7.01 at the Advanced Light Source was developed for very high-energy - (∼50 meV) and angular - ( 12 photons/sec) makes the detailed study of the evolution of bands possible. The authors are interested in learning how, when one forms a chemical bond between a metal and an overlaying atom or molecule, the resulting charge transfer to or from the adsorbate affects the surface bands. In some cases of interest, intermediate coverages lead to different band structure than at the extremes of clean and saturated surfaces. Surfaces of tungsten are particularly interesting, as their atomic geometry has been shown to be exquisitely sensitive to both the surface vibrational and electronic properties. In this study, the authors looked at the surface bands of tungsten ((110) surface), as a function both of coverage and mass of overlaying atoms. The adsorbed atoms were hydrogen and the alkali atoms lithium and cesium

  12. Large area optical mapping of surface contact angle.

    Science.gov (United States)

    Dutra, Guilherme; Canning, John; Padden, Whayne; Martelli, Cicero; Dligatch, Svetlana

    2017-09-04

    Top-down contact angle measurements have been validated and confirmed to be as good if not more reliable than side-based measurements. A range of samples, including industrially relevant materials for roofing and printing, has been compared. Using the top-down approach, mapping in both 1-D and 2-D has been demonstrated. The method was applied to study the change in contact angle as a function of change in silver (Ag) nanoparticle size controlled by thermal evaporation. Large area mapping reveals good uniformity for commercial Aspen paper coated with black laser printer ink. A demonstration of the forensic and chemical analysis potential in 2-D is shown by uncovering the hidden CsF initials made with mineral oil on the coated Aspen paper. The method promises to revolutionize nanoscale characterization and industrial monitoring as well as chemical analyses by allowing rapid contact angle measurements over large areas or large numbers of samples in ways and times that have not been possible before.

  13. Comparison of brass alloys composition by laser-induced breakdown spectroscopy and self-organizing maps

    Energy Technology Data Exchange (ETDEWEB)

    Pagnotta, Stefano; Grifoni, Emanuela; Legnaioli, Stefano [Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Lezzerini, Marco [Department of Earth Sciences, University of Pisa, Via S. Maria 53, 56126 Pisa (Italy); Lorenzetti, Giulia [Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Palleschi, Vincenzo, E-mail: vincenzo.palleschi@cnr.it [Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Department of Civilizations and Forms of Knowledge, University of Pisa, Via L. Galvani 1, 56126 Pisa (Italy)

    2015-01-01

    In this paper we face the problem of assessing similarities in the composition of different metallic alloys, using the laser-induced breakdown spectroscopy technique. The possibility of determining the degree of similarity through the use of artificial neural networks and self-organizing maps is discussed. As an example, we present a case study involving the comparison of two historical brass samples, very similar in their composition. The results of the paper can be extended to many other situations, not necessarily associated with cultural heritage and archeological studies, where objects with similar composition have to be compared. - Highlights: • A method for assessing the similarity of materials analyzed by LIBS is proposed. • Two very similar fragments of historical brass were analyzed. • Using a simple artificial neural network the composition of the two alloys was determined. • The composition of the two brass alloys was the same within the experimental error. • Using self-organizing maps, the probability of the alloys to have the same composition was assessed.

  14. Comparison of brass alloys composition by laser-induced breakdown spectroscopy and self-organizing maps

    International Nuclear Information System (INIS)

    Pagnotta, Stefano; Grifoni, Emanuela; Legnaioli, Stefano; Lezzerini, Marco; Lorenzetti, Giulia; Palleschi, Vincenzo

    2015-01-01

    In this paper we face the problem of assessing similarities in the composition of different metallic alloys, using the laser-induced breakdown spectroscopy technique. The possibility of determining the degree of similarity through the use of artificial neural networks and self-organizing maps is discussed. As an example, we present a case study involving the comparison of two historical brass samples, very similar in their composition. The results of the paper can be extended to many other situations, not necessarily associated with cultural heritage and archeological studies, where objects with similar composition have to be compared. - Highlights: • A method for assessing the similarity of materials analyzed by LIBS is proposed. • Two very similar fragments of historical brass were analyzed. • Using a simple artificial neural network the composition of the two alloys was determined. • The composition of the two brass alloys was the same within the experimental error. • Using self-organizing maps, the probability of the alloys to have the same composition was assessed

  15. Sensor-Motor Maps for Describing Linear Reflex Composition in Hopping.

    Science.gov (United States)

    Schumacher, Christian; Seyfarth, André

    2017-01-01

    In human and animal motor control several sensory organs contribute to a network of sensory pathways modulating the motion depending on the task and the phase of execution to generate daily motor tasks such as locomotion. To better understand the individual and joint contribution of reflex pathways in locomotor tasks, we developed a neuromuscular model that describes hopping movements. In this model, we consider the influence of proprioceptive length (LFB), velocity (VFB) and force feedback (FFB) pathways of a leg extensor muscle on hopping stability, performance and efficiency (metabolic effort). Therefore, we explore the space describing the blending of the monosynaptic reflex pathway gains. We call this reflex parameter space a sensor-motor map . The sensor-motor maps are used to visualize the functional contribution of sensory pathways in multisensory integration. We further evaluate the robustness of these sensor-motor maps to changes in tendon elasticity, body mass, segment length and ground compliance. The model predicted that different reflex pathway compositions selectively optimize specific hopping characteristics (e.g., performance and efficiency). Both FFB and LFB were pathways that enable hopping. FFB resulted in the largest hopping heights, LFB enhanced hopping efficiency and VFB had the ability to disable hopping. For the tested case, the topology of the sensor-motor maps as well as the location of functionally optimal compositions were invariant to changes in system designs (tendon elasticity, body mass, segment length) or environmental parameters (ground compliance). Our results indicate that different feedback pathway compositions may serve different functional roles. The topology of the sensor-motor map was predicted to be robust against changes in the mechanical system design indicating that the reflex system can use different morphological designs, which does not apply for most robotic systems (for which the control often follows a specific

  16. Composite Fermi surface in the half-filled Landau level with anisotropic electron mass

    Science.gov (United States)

    Ippoliti, Matteo; Geraedts, Scott; Bhatt, Ravindra

    We study the problem of interacting electrons in the lowest Landau level at half filling in the quantum Hall regime, when the electron dispersion is given by an anisotropic mass tensor. Based on experimental observations and theoretical arguments, the ground state of the system is expected to consist of composite Fermions filling an elliptical Fermi sea, with the anisotropy of the ellipse determined by the competing effects of the isotropic Coulomb interaction and anisotropic electron mass tensor. We test this idea quantitatively by using a numerical density matrix renormalization group method for quantum Hall systems on an infinitely long cylinder. Singularities in the structure factor allow us to map the Fermi surface of the composite Fermions. We compute the composite Fermi surface anisotropy for several values of the electron mass anisotropy which allow us to deduce the functional dependence of the former on the latter. This research was supported by Department of Energy Office of Basic Energy Sciences through Grant No. DE-SC0002140.

  17. Mapping physicochemical surface modifications of flame-treated polypropylene

    Directory of Open Access Journals (Sweden)

    S. Farris

    2014-04-01

    Full Text Available The aim of this work was to investigate how the surface morphology of polypropylene (PP is influenced by the surface activation mediated by a flame obtained using a mixture of air and propane under fuel-lean (equivalence ratio φ = 0.98 conditions. Morphological changes observed on flamed samples with smooth (S, medium (M, and high (H degree of surface roughness were attributed to the combined effect of a chemical mechanism (agglomeration and ordering of partially oxidized intermediate-molecular-weight material with a physical mechanism (flattening of the original roughness by the flame’s high temperature. After two treatments, the different behavior of the samples in terms of wettability was totally reset, which made an impressive surface energy of ~43 mJ•m–2 possible, which is typical of more hydrophilic polymers (e.g., polyethylene terephthalate – PET. In particular, the polar component was increased from 1.21, 0.08, and 0.32 mJ•m–2 (untreated samples to 10.95, 11.20, and 11.17 mJ•m–2 for the flamed samples S, M, and H, respectively, an increase attributed to the insertion of polar functional groups (hydroxyl and carbonyl on the C–C backbone, as demonstrated by the X-ray photoelectron spectroscopy results.

  18. Face recognition based on depth maps and surface curvature

    Science.gov (United States)

    Gordon, Gaile G.

    1991-09-01

    This paper explores the representation of the human face by features based on the curvature of the face surface. Curature captures many features necessary to accurately describe the face, such as the shape of the forehead, jawline, and cheeks, which are not easily detected from standard intensity images. Moreover, the value of curvature at a point on the surface is also viewpoint invariant. Until recently range data of high enough resolution and accuracy to perform useful curvature calculations on the scale of the human face had been unavailable. Although several researchers have worked on the problem of interpreting range data from curved (although usually highly geometrically structured) surfaces, the main approaches have centered on segmentation by signs of mean and Gaussian curvature which have not proved sufficient in themselves for the case of the human face. This paper details the calculation of principal curvature for a particular data set, the calculation of general surface descriptors based on curvature, and the calculation of face specific descriptors based both on curvature features and a priori knowledge about the structure of the face. These face specific descriptors can be incorporated into many different recognition strategies. A system that implements one such strategy, depth template comparison, giving recognition rates between 80% and 90% is described.

  19. A structural model for composite rotor blades and lifting surfaces

    Science.gov (United States)

    Rehfield, Lawrence W.; Atilgan, Ali R.

    1987-01-01

    Composite material systems are currently candidates for aerospace structures, primarily for the design flexibiity they offer i.e., it is possible to tailor the material and manufacturing approach to the application. Two notable examples are the wing of the Grumman/USAF/DARPA X-29 and rotor blades under development by the U.S.A. Aerostructures Directorate (AVSCOM), Langley Research Center. A working definition of elastic or structural tailoring is the use of structural concept, fiber orientation, ply stacking sequence, and a blend of materials to achieve specific performance goals. In the design process, choices of materials and dimensions are made which produce specific response characteristics which permit the selected goals to be achieved. Common choices for tailoring goals are preventing instabilities or vibration resonances or enhancing damage tolerance. An essential, enabling factor in the design of tailored composite structures is structural modeling that accurately, but simply, characterizes response. The objective of this paper is to improve the single-cell beam model for composite rotor blades or lifting surfaces and to demonstrate its usefullness in applications.

  20. Advanced surface chemical analysis of continuously manufactured drug loaded composite pellets.

    Science.gov (United States)

    Hossain, Akter; Nandi, Uttom; Fule, Ritesh; Nokhodchi, Ali; Maniruzzaman, Mohammed

    2017-04-15

    The aim of the present study was to develop and characterise polymeric composite pellets by means of continuous melt extrusion techniques. Powder blends of a steroid hormone (SH) as a model drug and either ethyl cellulose (EC N10 and EC P7 grades) or hydroxypropyl methylcellulose (HPMC AS grade) as polymeric carrier were extruded using a Pharma 11mm twin screw extruder in a continuous mode of operation to manufacture extruded composite pellets of 1mm length. Molecular modelling study using commercial Gaussian 09 software outlined a possible drug-polymer interaction in the molecular level to develop solid dispersions of the drug in the pellets. Solid-state analysis conducted via a differential scanning calorimetry (DSC), hot stage microscopy (HSM) and X-ray powder diffraction (XRPD) analyses revealed the amorphous state of the drug in the polymer matrices. Surface analysis using SEM/energy dispersive X-ray (EDX) of the produced pellets arguably showed a homogenous distribution of the C and O atoms in the pellet matrices. Moreover, advanced chemical surface analysis conducted via atomic force microscopy (AFM) showed a homogenous phase system having the drug molecule dispersed onto the amorphous matrices while Raman mapping confirmed the homogenous single-phase drug distribution in the manufactured composite pellets. Such composite pellets are expected to deliver multidisciplinary applications in drug delivery and medical sciences by e.g. modifying drug solubility/dissolutions or stabilizing the unstable drug (e.g. hormone, protein) in the composite network. Copyright © 2016. Published by Elsevier Inc.

  1. Mesoscopic Strains Maps in Woven Composite Laminas During Off-axis Tension

    Directory of Open Access Journals (Sweden)

    Nicoletto G.

    2010-06-01

    eliminate the random 3D influence of multiple-ply laminates and to favor computational model validation. Specimens with different loading directions with respect to the material principal directions were prepared and tested in a servo-hydraulic testing machine. Specimen surface preparation consisted in a speckle pattern generation to allow the application of the DIC tecnique. During the tensile experiment, the speckle pattern is recorded (frame rate of 0.1 picture/second using a CCD camera equipped with a microscopic lens and adjustable light sources. In-house DIC software was used for in-plane displacement and strain determination and mapping. For brevity only the case of loading in the tow yarn direction is considered here. Fig. 1b shows a tipical strain map obtained with the DIC technique at an applied macroscopic strain of 0.9%. The strains are small but the DIC dechnique is sensitive enough and suitable filtering reduce the noise level of the strain maps. Strong local strain gradients are determined and referred to the yarn architecture in Fig. 1c. The DIC measurements were validated by averaging the strain over the field of view and comparing it with the macroscopic strain given by a high-sensitivity MTS extensometer. The mesoscopic srain data obtained with DIC are used to assess and validate parallel material model development by direct FEM vs experimental strain correlation. Fig. 2a shows the FEM model of the unit cell for the twill-weave architecture with a detail of the yarn geometry and finite element discretization. Suitable boundary conditions are applied to the UC model contours before the analysis, [1]. Fig. 2b shows and example of the comparison of the local longitudinal FEM/DIC strain distribution along a transverse line of Fig. 1c. The comparison shows the excellent correlation achieved both in terms of gradients and absolute strain values, [3].

  2. Quantitative Susceptibility Mapping of Human Brain Reflects Spatial Variation in Tissue Composition

    Science.gov (United States)

    Li, Wei; Wu, Bing; Liu, Chunlei

    2011-01-01

    Image phase from gradient echo MRI provides a unique contrast that reflects brain tissue composition variations, such as iron and myelin distribution. Phase imaging is emerging as a powerful tool for the investigation of functional brain anatomy and disease diagnosis. However, the quantitative value of phase is compromised by its nonlocal and orientation dependent properties. There is an increasing need for reliable quantification of magnetic susceptibility, the intrinsic property of tissue. In this study, we developed a novel and accurate susceptibility mapping method that is also phase-wrap insensitive. The proposed susceptibility mapping method utilized two complementary equations: (1) the Fourier relationship of phase and magnetic susceptibility; and (2) the first-order partial derivative of the first equation in the spatial frequency domain. In numerical simulation, this method reconstructed the susceptibility map almost free of streaking artifact. Further, the iterative implementation of this method allowed for high quality reconstruction of susceptibility maps of human brain in vivo. The reconstructed susceptibility map provided excellent contrast of iron-rich deep nuclei and white matter bundles from surrounding tissues. Further, it also revealed anisotropic magnetic susceptibility in brain white matter. Hence, the proposed susceptibility mapping method may provide a powerful tool for the study of brain physiology and pathophysiology. Further elucidation of anisotropic magnetic susceptibility in vivo may allow us to gain more insight into the white matter microarchitectures. PMID:21224002

  3. On the Gauss Map of Surfaces of Revolution with Lightlike Axis in Minkowski 3-Space

    Directory of Open Access Journals (Sweden)

    Minghao Jin

    2013-01-01

    Full Text Available By studying the Gauss map G and Laplace operator Δh of the second fundamental form h, we will classify surfaces of revolution with a lightlike axis in 3-dimensional Minkowski space and also obtain the surface of Enneper of the 2nd kind, the surface of Enneper of the 3rd kind, the de Sitter pseudosphere, and the hyperbolic pseudosphere that satisfy condition ΔhG=ΛG, Λ being a 3×3 real matrix.

  4. Mineral and chemical composition of rock core and surface gas composition in Horonobe Underground Research Laboratory project. Phase 1

    International Nuclear Information System (INIS)

    Hiraga, Naoto; Ishii, Eiichi

    2008-02-01

    The following three kinds of analyses were conducted for the 1st phase of the Horonobe Underground Research Laboratory Project. Mineral composition analysis of core sample. Whole rock chemical composition analysis of core sample. Surface gas composition analysis. This document summarizes the results of these analyses. (author)

  5. A novel method of S-box design based on chaotic map and composition method

    International Nuclear Information System (INIS)

    Lambić, Dragan

    2014-01-01

    Highlights: • Novel chaotic S-box generation method is presented. • Presented S-box has better cryptographic properties than other examples of chaotic S-boxes. • The advantages of the proposed method are the low complexity and large key space. -- Abstract: An efficient algorithm for obtaining random bijective S-boxes based on chaotic maps and composition method is presented. The proposed method is based on compositions of S-boxes from a fixed starting set. The sequence of the indices of starting S-boxes used is obtained by using chaotic maps. The results of performance test show that the S-box presented in this paper has good cryptographic properties. The advantages of the proposed method are the low complexity and the possibility to achieve large key space

  6. Mapping quantitative trait loci (QTLs for fatty acid composition in an interspecific cross of oil palm

    Directory of Open Access Journals (Sweden)

    Sharma Mukesh

    2009-08-01

    Full Text Available Abstract Background Marker Assisted Selection (MAS is well suited to a perennial crop like oil palm, in which the economic products are not produced until several years after planting. The use of DNA markers for selection in such crops can greatly reduce the number of breeding cycles needed. With the use of DNA markers, informed decisions can be made at the nursery stage, regarding which individuals should be retained as breeding stock, which are satisfactory for agricultural production, and which should be culled. The trait associated with oil quality, measured in terms of its fatty acid composition, is an important agronomic trait that can eventually be tracked using molecular markers. This will speed up the production of new and improved oil palm planting materials. Results A map was constructed using AFLP, RFLP and SSR markers for an interspecific cross involving a Colombian Elaeis oleifera (UP1026 and a Nigerian E. guinneensis (T128. A framework map was generated for the male parent, T128, using Joinmap ver. 4.0. In the paternal (E. guineensis map, 252 markers (199 AFLP, 38 RFLP and 15 SSR could be ordered in 21 linkage groups (1815 cM. Interval mapping and multiple-QTL model (MQM mapping (also known as composite interval mapping, CIM were used to detect quantitative trait loci (QTLs controlling oil quality (measured in terms of iodine value and fatty acid composition. At a 5% genome-wide significance threshold level, QTLs associated with iodine value (IV, myristic acid (C14:0, palmitic acid (C16:0, palmitoleic acid (C16:1, stearic acid (C18:0, oleic acid (C18:1 and linoleic acid (C18:2 content were detected. One genomic region on Group 1 appears to be influencing IV, C14:0, C16:0, C18:0 and C18:1 content. Significant QTL for C14:0, C16:1, C18:0 and C18:1 content was detected around the same locus on Group 15, thus revealing another major locus influencing fatty acid composition in oil palm. Additional QTL for C18:0 was detected on Group 3

  7. Developing Coastal Surface Roughness Maps Using ASTER and QuickBird Data Sources

    Science.gov (United States)

    Spruce, Joe; Berglund, Judith; Davis, Bruce

    2006-01-01

    This viewgraph presentation regards one element of a larger project on the integration of NASA science models and data into the Hazards U.S. Multi-Hazard (HAZUS-MH) Hurricane module for hurricane damage and loss risk assessment. HAZUS-MH is a decision support tool being developed by the National Institute of Building Sciences for the Federal Emergency Management Agency (FEMA). It includes the Hurricane Module, which employs surface roughness maps made from National Land Cover Data (NLCD) maps to estimate coastal hurricane wind damage and loss. NLCD maps are produced and distributed by the U.S. Geological Survey. This presentation discusses an effort to improve upon current HAZUS surface roughness maps by employing ASTER multispectral classifications with QuickBird "ground reference" imagery.

  8. Re-discovering surface mass spectrometry: chemical mapping from micro to macro

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, K.G.; O' Keefe, D.P

    2004-06-15

    New developments in electronics, devices, micro-encapsulation, and other areas demand the ability to acquire molecularly-specific information from smaller and smaller features. ToF-SIMS provides molecularly-specific mass spectral data, but sufficient high-mass signal has historically been difficult to obtain from organic/polymeric surfaces in the point-mapping mode of operation. Use of chemometric data reduction methods and the development of heavier primary ion sources enhance and extend the chemical information in the mapping data. Large-area chemical mapping via sample stage rastering has also opened up new applications. This capability allows single-experiment mapping of large or multiple features, provides information on surface uniformity over end-use-relevant areas, and offers potential for combinatorial and other screening applications. Examples of these applications are presented.

  9. Mapping visual cortex in monkeys and humans using surface-based atlases

    Science.gov (United States)

    Van Essen, D. C.; Lewis, J. W.; Drury, H. A.; Hadjikhani, N.; Tootell, R. B.; Bakircioglu, M.; Miller, M. I.

    2001-01-01

    We have used surface-based atlases of the cerebral cortex to analyze the functional organization of visual cortex in humans and macaque monkeys. The macaque atlas contains multiple partitioning schemes for visual cortex, including a probabilistic atlas of visual areas derived from a recent architectonic study, plus summary schemes that reflect a combination of physiological and anatomical evidence. The human atlas includes a probabilistic map of eight topographically organized visual areas recently mapped using functional MRI. To facilitate comparisons between species, we used surface-based warping to bring functional and geographic landmarks on the macaque map into register with corresponding landmarks on the human map. The results suggest that extrastriate visual cortex outside the known topographically organized areas is dramatically expanded in human compared to macaque cortex, particularly in the parietal lobe.

  10. Mapping Hfq-RNA interaction surfaces using tryptophan fluorescence quenching

    Science.gov (United States)

    Robinson, Kirsten E.; Orans, Jillian; Kovach, Alexander R.; Link, Todd M.; Brennan, Richard G.

    2014-01-01

    Hfq is a posttranscriptional riboregulator and RNA chaperone that binds small RNAs and target mRNAs to effect their annealing and message-specific regulation in response to environmental stressors. Structures of Hfq-RNA complexes indicate that U-rich sequences prefer the proximal face and A-rich sequences the distal face; however, the Hfq-binding sites of most RNAs are unknown. Here, we present an Hfq-RNA mapping approach that uses single tryptophan-substituted Hfq proteins, all of which retain the wild-type Hfq structure, and tryptophan fluorescence quenching (TFQ) by proximal RNA binding. TFQ properly identified the respective distal and proximal binding of A15 and U6 RNA to Gram-negative Escherichia coli (Ec) Hfq and the distal face binding of (AA)3A, (AU)3A and (AC)3A to Gram-positive Staphylococcus aureus (Sa) Hfq. The inability of (GU)3G to bind the distal face of Sa Hfq reveals the (R-L)n binding motif is a more restrictive (A-L)n binding motif. Remarkably Hfq from Gram-positive Listeria monocytogenes (Lm) binds (GU)3G on its proximal face. TFQ experiments also revealed the Ec Hfq (A-R-N)n distal face-binding motif should be redefined as an (A-A-N)n binding motif. TFQ data also demonstrated that the 5′-untranslated region of hfq mRNA binds both the proximal and distal faces of Ec Hfq and the unstructured C-terminus. PMID:24288369

  11. Surface Composition of Trojan Asteroids from Thermal-Infrared Spectroscopy

    Science.gov (United States)

    Martin, A.; Emery, J. P.; Lindsay, S. S.

    2017-12-01

    Asteroid origins provide an effective means of constraining the events that dynamically shaped the solar system. Jupiter Trojan asteroids (hereafter Trojans) may help in determining the extent of radial mixing that occurred during giant planet migration. Previous studies aimed at characterizing surface composition show that Trojans have low albedo surfaces and fall into two distinct spectral groups the near infrared (NIR). Though, featureless in this spectral region, NIR spectra of Trojans either exhibit a red or less-red slope. Typically, red-sloped spectra are associated with organics, but it has been shown that Trojans are not host to much, if any, organic material. Instead, the red slope is likely due to anhydrous silicates. The thermal infrared (TIR) wavelength range has advantages for detecting silicates on low albedo asteroids such as Trojans. The 10 µm region exhibits strong features due to the Si-O fundamental molecular vibrations. We hypothesize that the two Trojan spectral groups have different compositions (silicate mineralogy). With TIR spectra from the Spitzer Space Telescope, we identify mineralogical features from the surface of 11 Trojan asteroids, five red and six less-red. Preliminary results from analysis of the 10 µm region indicate red-sloped Trojans have a higher spectral contrast compared to less-red-sloped Trojans. Fine-grain mixtures of crystalline pyroxene and olivine exhibit a 10 µm feature with sharp cutoffs between about 9 µm and 12 µm, which create a broad flat plateau. Amorphous phases, when present, smooth the sharp emission features, resulting in a dome-like shape. Further spectral analysis in the 10 µm, 18 µm, and 30 µm band region will be performed for a more robust analysis. If all Trojans come from the same region, it is expected that they share spectral and compositional characteristics. Therefore, if spectral analysis in the TIR reinforce the NIR spectral slope dichotomy, it is likely that Trojans were sourced from

  12. A chord diagrammatic presentation of the mapping class group of a once bordered surface

    DEFF Research Database (Denmark)

    Bene, Alex

    2010-01-01

    of Teichmüller space with a discrete set objects. In particular, it leads to an infinite, but combinatorially simple, presentation of the mapping class group of an orientable surface. In this note, we give a presentation of a full mapping class group equivariant subgroupoid of the Ptolemy groupoid......The Ptolemy groupoid is a combinatorial groupoid generated by elementary moves on marked trivalent fatgraphs with three types of relations. Through the fatgraph decomposition of Teichmüller space, the Ptolemy groupoid is a mapping class group equivariant subgroupoid of the fundamental path groupoid...

  13. A Chord Diagrammatic Presentation of the Mapping Class Group of a Once Bordered Surface

    DEFF Research Database (Denmark)

    Bene, Alex

    groupoid of Teichm\\"uller space with a discrete set objects. In particular, it leads to an infinite, but combinatorially simple, presentation of the mapping class group of an orientable surface. In this note, we give a presentation of a full mapping class group equivariant subgroupoid of the Ptolemy......The Ptolemy groupoid is a combinatorial groupoid generated by elementary moves on marked trivalent fatgraphs with three types of relations. Through the fatgraph decomposition of Teichm\\"uller space, the Ptolemy groupoid is a mapping class group equivariant subgroupoid of the fundamental path...

  14. Regional quantitative analysis of cortical surface maps of FDG PET images

    CERN Document Server

    Protas, H D; Hayashi, K M; Chin Lung, Yu; Bergsneider, M; Sung Cheng, Huang

    2006-01-01

    Cortical surface maps are advantageous for visualizing the 3D profile of cortical gray matter development and atrophy, and for integrating structural and functional images. In addition, cortical surface maps for PET data, when analyzed in conjunction with structural MRI data allow us to investigate, and correct for, partial volume effects. Here we compared quantitative regional PET values based on a 3D cortical surface modeling approach with values obtained directly from the 3D FDG PET images in various atlas-defined regions of interest (ROIs; temporal, parietal, frontal, and occipital lobes). FDG PET and 3D MR (SPGR) images were obtained and aligned to ICBM space for 15 normal subjects. Each image was further elastically warped in 2D parameter space of the cortical surface, to align major cortical sulci. For each point within a 15 mm distance of the cortex, the value of the PET intensity was averaged to give a cortical surface map of FDG uptake. The average PET values on the cortical surface map were calcula...

  15. Waste-surface mapping of the Fernald K-65 silos using a structured light measurement system

    International Nuclear Information System (INIS)

    Burks, B.L.; DePiero, F.W.; Dinkins, M.A.; Rowe, J.C.; Selleck, C.B.; Jacoboski, D.L.

    1992-10-01

    A remotely operated surface-mapping measurement system was developed by the Robotics ampersand Process Systems Division at Oak Ridge National Laboratory for use in the K-65 waste-storage silos at Fernald, Ohio. The mapping system used three infrared line-generating laser diodes as illumination sources and three high-resolution, low-lux, calibrated, black-and-white, charge-coupled-device video cameras as receivers. These components were combined to form structured light source range and direction sensors with six different possible emitter-receiver pairs. A technology demonstration and predeployment tests were performed at Fernald using the empty Silo 4 into which was placed rectangular objects of known dimensions. These objects were scanned by the structured light sources to demonstrate functionality and verify that the system was giving sufficiently accurate range data in three dimensions. The structured light sources were deployed in Silos 1 and 2 to scan the waste surfaces. The resulting data were merged to create three-dimensional maps of those surfaces. A bentonite clay cap was placed over the waste surfaces and surface maps were obtained. The change in surface height before and after bentonite addition was utilized as a measure of clay cap thickness

  16. Mapping 2000 2010 Impervious Surface Change in India Using Global Land Survey Landsat Data

    Science.gov (United States)

    Wang, Panshi; Huang, Chengquan; Brown De Colstoun, Eric C.

    2017-01-01

    Understanding and monitoring the environmental impacts of global urbanization requires better urban datasets. Continuous field impervious surface change (ISC) mapping using Landsat data is an effective way to quantify spatiotemporal dynamics of urbanization. It is well acknowledged that Landsat-based estimation of impervious surface is subject to seasonal and phenological variations. The overall goal of this paper is to map 200-02010 ISC for India using Global Land Survey datasets and training data only available for 2010. To this end, a method was developed that could transfer the regression tree model developed for mapping 2010 impervious surface to 2000 using an iterative training and prediction (ITP) approach An independent validation dataset was also developed using Google Earth imagery. Based on the reference ISC from the validation dataset, the RMSE of predicted ISC was estimated to be 18.4%. At 95% confidence, the total estimated ISC for India between 2000 and 2010 is 2274.62 +/- 7.84 sq km.

  17. Surface peptide mapping of protein I and protein III of four strains of Neisseria gonorrhoeae

    International Nuclear Information System (INIS)

    Judd, R.C.

    1982-01-01

    Whole cells and isolated outer membranes (OMs) of four strains of gonococci were surface radioiodinated with either lactoperoxidase or Iodogen (Pierce Chemical Co., Rockford, Ill.). These preparations were solubilized in sodium dodecyl sulfate and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Surface-radioiodinated protein I (PI) and PIII bands were excised from the sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels and digested with alpha-chymotrypsin, and the resultant 125 I-peptide fragments were resolved by high-voltage electrophoresis and thin-layer chromatography (i.e., surface peptide mapping). Radioemitting peptidic fragments were visualized by autoradiography. Results demonstrated that the PI molecule of each gonococcal strain studied had unique iodinatable peptides exposed on the surface of whole cells and OMs, whereas PIIIs appeared to have the same portion of the molecule exposed on the surface of bacteria or OMs, regardless of the gonococcal strain from which they were isolated. Many more radiolabeled peptides were seen in surface peptide maps of PIs from radiolabeled OMs than in those from radioiodinated whole cells, whereas different peptidic fragments were seen in the surface peptide maps of PIIIs from radiolabeled OMs than were seen in those from radiolabeled whole cells. These data suggest that PI may contribute strain-specific antigenic determinants and PIII may contribute cross-reactive determinants and that the surface exposure of PI and PIII is different in isolated OMs than in the OM of intact gonococci

  18. Eastern Denali Fault surface trace map, eastern Alaska and Yukon, Canada

    Science.gov (United States)

    Bender, Adrian M.; Haeussler, Peter J.

    2017-05-04

    We map the 385-kilometer (km) long surface trace of the right-lateral, strike-slip Denali Fault between the Totschunda-Denali Fault intersection in Alaska, United States and the village of Haines Junction, Yukon, Canada. In Alaska, digital elevation models based on light detection and ranging and interferometric synthetic aperture radar data enabled our fault mapping at scales of 1:2,000 and 1:10,000, respectively. Lacking such resources in Yukon, we developed new structure-from-motion digital photogrammetry products from legacy aerial photos to map the fault surface trace at a scale of 1:10,000 east of the international border. The section of the fault that we map, referred to as the Eastern Denali Fault, did not rupture during the 2002 Denali Fault earthquake (moment magnitude 7.9). Seismologic, geodetic, and geomorphic evidence, along with a paleoseismic record of past ground-rupturing earthquakes, demonstrate Holocene and contemporary activity on the fault, however. This map of the Eastern Denali Fault surface trace complements other data sets by providing an openly accessible digital interpretation of the location, length, and continuity of the fault’s surface trace based on the accompanying digital topography dataset. Additionally, the digitized fault trace may provide geometric constraints useful for modeling earthquake scenarios and related seismic hazard.

  19. Evaluation of Alternative Peel Ply Surface Preparation Methods of SC-15 Epoxy / Fiberglass Composite Surfaces for Secondary Bonding

    Science.gov (United States)

    2014-01-01

    prepared composite surfaces. Examination of the surface compositions will show differences in makeup and identify any transfer of contaminants...by carefully brushing the specimen with a lint-free cloth followed by a high-pressure nitrogen gas stream. 3.2 X-ray Photospectroscopy (XPS

  20. Surface protein composition of Aeromonas hydrophila strains virulent for fish: identification of a surface array protein

    International Nuclear Information System (INIS)

    Dooley, J.S.G.; Trust, T.J.

    1988-01-01

    The surface protein composition of members of a serogroup of Aeromonas hydrophila was examined. Immunoblotting with antiserum raised against formalinized whole cells of A. hydrophila TF7 showed a 52K S-layer protein to be the major surface protein antigen, and impermeant Sulfo-NHS-Biotin cell surface labeling showed that the 52K S-layer protein was the only protein accessible to the Sulfo-NHS-Biotin label and effectively masked underlying outer membrane (OM) proteins. In its native surface conformation the 52K S-layer protein was only weakly reactive with a lactoperoxidase 125 I surface iodination procedure. A UV-induced rough lipopolysaccharide (LPS) mutant of TF7 was found to produce an intact S layer, but a deep rough LPS mutant was unable to maintain an array on the cell surface and excreted the S-layer protein into the growth medium, indicating that a minimum LPS oligosaccharide size required for A. hydrophila S-layer anchoring. The native S layer was permeable to 125 I in the lactoperoxidase radiolabeling procedure, and two major OM proteins of molecular weights 30,000 and 48,000 were iodinated. The 48K species was a peptidoglycan-associated, transmembrane protein which exhibited heat-modifiable SDS solubilization behavior characteristic of a porin protein. A 50K major peptidoglycan-associated OM protein which was not radiolabeled exhibited similar SDS heat modification characteristics and possibly represents a second porin protein

  1. Surface Functionalization of Thin-Film Composite Membranes with Copper Nanoparticles for Antimicrobial Surface Properties

    KAUST Repository

    Ben-Sasson, Moshe

    2014-01-07

    Biofouling is a major operational challenge in reverse osmosis (RO) desalination, motivating a search for improved biofouling control strategies. Copper, long known for its antibacterial activity and relatively low cost, is an attractive potential biocidal agent. In this paper, we present a method for loading copper nanoparticles (Cu-NPs) on the surface of a thin-film composite (TFC) polyamide RO membrane. Cu-NPs were synthesized using polyethyleneimine (PEI) as a capping agent, resulting in particles with an average radius of 34 nm and a copper content between 39 and 49 wt.%. The positive charge of the Cu-NPs imparted by the PEI allowed a simple electrostatic functionalization of the negatively charged RO membrane. We confirmed functionalization and irreversible binding of the Cu-NPs to the membrane surface with SEM and XPS after exposing the membrane to bath sonication. We also demonstrated that Cu-NP functionalization can be repeated after the Cu-NPs dissolve from the membrane surface. The Cu-NP functionalization had minimal impact on the intrinsic membrane transport parameters. Surface hydrophilicity and surface roughness were also maintained, and the membrane surface charge became positive after functionalization. The functionalized membrane exhibited significant antibacterial activity, leading to an 80-95% reduction in the number of attached live bacteria for three different model bacterial strains. Challenges associated with this functionalization method and its implementation in RO desalination are discussed. © 2013 American Chemical Society.

  2. Surface Functionalization of Thin-Film Composite Membranes with Copper Nanoparticles for Antimicrobial Surface Properties

    KAUST Repository

    Ben-Sasson, Moshe; Zodrow, Katherine R.; Genggeng, Qi; Kang, Yan; Giannelis, Emmanuel P.; Elimelech, Menachem

    2014-01-01

    Biofouling is a major operational challenge in reverse osmosis (RO) desalination, motivating a search for improved biofouling control strategies. Copper, long known for its antibacterial activity and relatively low cost, is an attractive potential biocidal agent. In this paper, we present a method for loading copper nanoparticles (Cu-NPs) on the surface of a thin-film composite (TFC) polyamide RO membrane. Cu-NPs were synthesized using polyethyleneimine (PEI) as a capping agent, resulting in particles with an average radius of 34 nm and a copper content between 39 and 49 wt.%. The positive charge of the Cu-NPs imparted by the PEI allowed a simple electrostatic functionalization of the negatively charged RO membrane. We confirmed functionalization and irreversible binding of the Cu-NPs to the membrane surface with SEM and XPS after exposing the membrane to bath sonication. We also demonstrated that Cu-NP functionalization can be repeated after the Cu-NPs dissolve from the membrane surface. The Cu-NP functionalization had minimal impact on the intrinsic membrane transport parameters. Surface hydrophilicity and surface roughness were also maintained, and the membrane surface charge became positive after functionalization. The functionalized membrane exhibited significant antibacterial activity, leading to an 80-95% reduction in the number of attached live bacteria for three different model bacterial strains. Challenges associated with this functionalization method and its implementation in RO desalination are discussed. © 2013 American Chemical Society.

  3. Microwave and plasma-assisted modification of composite fiber surface topography

    Science.gov (United States)

    Paulauskas, Felix L [Knoxville, TN; White, Terry L [Knoxville, TN; Bigelow, Timothy S [Knoxville, TN

    2003-02-04

    The present invention introduces a novel method for producing an undulated surface on composite fibers using plasma technology and microwave radiation. The undulated surface improves the mechanical interlocking of the fibers to composite resins and enhances the mechanical strength and interfacial sheer strength of the composites in which they are introduced.

  4. Impact source location on composite CNG storage tank using acoustic emission energy based signal mapping method

    Energy Technology Data Exchange (ETDEWEB)

    Han, Byeong Hee; Yoon, Dong Jin; Park, Chun Soo [Korea Research Institute of Standards and Science, Center for Safety Measurement, Daejeon (Korea, Republic of); Lee, Young Shin [Dept. of Mechanical Design Engineering, Chungnam National University, Daejeon (Korea, Republic of)

    2016-10-15

    Acoustic emission (AE) is one of the most powerful techniques for detecting damages and identify damage location during operations. However, in case of the source location technique, there is some limitation in conventional AE technology, because it strongly depends on wave speed in the corresponding structures having heterogeneous composite materials. A compressed natural gas(CNG) pressure vessel is usually made of carbon fiber composite outside of vessel for the purpose of strengthening. In this type of composite material, locating impact damage sources exactly using conventional time arrival method is difficult. To overcome this limitation, this study applied the previously developed Contour D/B map technique to four types of CNG storage tanks to identify the source location of damages caused by external shock. The results of the identification of the source location for different types were compared.

  5. Hot Deformation Behavior and Processing Maps of Diamond/Cu Composites

    Science.gov (United States)

    Zhang, Hongdi; Liu, Yue; Zhang, Fan; Zhang, Di; Zhu, Hanxing; Fan, Tongxiang

    2018-06-01

    The hot deformation behaviors of 50 vol pct uncoated and Cr-coated diamond/Cu composites were investigated using hot isothermal compression tests under the temperature and strain rate ranging from 1073 K to 1273 K (800 °C to 1000 °C) and from 0.001 to 5 s-1, respectively. Dynamic recrystallization was determined to be the primary restoration mechanism during deformation. The Cr3C2 coating enhanced the interfacial bonding and resulted in a larger flow stress for the Cr-coated diamond/Cu composites. Moreover, the enhanced interfacial affinity led to a higher activation energy for the Cr-coated diamond/Cu composites (238 kJ/mol) than for their uncoated counterparts (205 kJ/mol). The strain-rate-dependent constitutive equations of the diamond/Cu composites were derived based on the Arrhenius model, and a high correlation ( R = 0.99) was observed between the calculated flow stresses and experimental data. With the help of processing maps, hot extrusions were realized at 1123 K/0.01 s-1 and 1153 K/0.01 s-1 (850 °C/0.01 s-1 and 880 °C/0.01 s-1) for the uncoated and coated diamond/Cu composites, respectively. The combination of interface optimization and hot extrusion led to increases of the density and thermal conductivity, thereby providing a promising route for the fabrication of diamond/Cu composites.

  6. Surface properties of thermally treated composite wood panels

    Science.gov (United States)

    Croitoru, Catalin; Spirchez, Cosmin; Lunguleasa, Aurel; Cristea, Daniel; Roata, Ionut Claudiu; Pop, Mihai Alin; Bedo, Tibor; Stanciu, Elena Manuela; Pascu, Alexandru

    2018-04-01

    Composite finger-jointed spruce and oak wood panels have been thermally treated under standard pressure and oxygen content conditions at two different temperatures, 180 °C and respectively 200 °C for short time periods (3 and 5 h). Due to the thermally-aided chemical restructuration of the wood components, a decrease in water uptake and volumetric swelling values with up to 45% for spruce and 35% for oak have been registered, comparing to the reference samples. In relation to water resistance, a 15% increase of the dispersive component of the surface energy has been registered for the thermal-treated spruce panels, which impedes water spreading on the surface. The thermal-treated wood presents superior resistance to accelerated UV exposure and subsequently, with up to 10% higher Brinell hardness values than reference wood. The proposed thermal treatment improves the durability of the finger-jointed wood through a more economically and environmental friendly method than traditional impregnation, with minimal degradative impact on the structural components of wood.

  7. Near Surface CO2 Triple Oxygen Isotope Composition

    Directory of Open Access Journals (Sweden)

    Sasadhar Mahata

    2016-02-01

    Full Text Available The isotopic composition of carbon dioxide in the atmosphere is a powerful tool for constraining its sources and sinks. In particular, the 17O oxygen anomaly [Δ17O = 1000 × ln(1 + δ17O/1000 - 0.516 × 1000 × ln(1 + δ18O/1000], with a value > 0.5‰ produced in the middle atmosphere, provides an ideal tool for probing the exchange of carbon dioxide between the biosphere/hydrosphere and atmosphere. The biosphere/hydrosphere and anthropogenic emissions give values ≤ 0.3‰. Therefore, any anomaly in near surface CO2 would reflect the balance between stratospheric input and exchange with the aforementioned surface sources. We have analyzed Δ17O values of CO2 separated from air samples collected in Taipei, Taiwan, located in the western Pacific region. The obtained mean anomaly is 0.42 ± 0.14‰ (1-σ standard deviation, in good agreement with model prediction and a published decadal record. Apart from typically used δ13C and δ18O values, the Δ17O value could provide an additional tracer for constraining the carbon cycle.

  8. Adhesion mapping of chemically modified and poly(ethylene oxide)-grafted glass surfaces

    OpenAIRE

    Jogikalmath, G.; Stuart, J.K.; Pungor, A.; Hlady, V.

    1999-01-01

    Two-dimensional mapping of the adhesion pull-off forces was used to study the origin of surface heterogeneity in the grafted poly(ethylene oxide) (PEO) layer. The variance of the pull-off forces measured over the μm-sized regions after each chemical step of modifying glass surfaces was taken to be a measure of the surface chemical heterogeneity. The attachment of γ-glycidoxypropyltrimethoxy silane (GPS) to glass decreased the pull-off forces relative to the clean glass and made the surface mo...

  9. Surface Compositions of Red Giant Stars in Globular Clusters

    Science.gov (United States)

    Cheng, Eric; Lau, Marie; Smith, Graeme; Chen, Brian

    2018-01-01

    Globular clusters (GCs) are excellent “laboratories” to study the formation and evolution of our galaxy. In order to understand, more specifically, the chemical compositions and stellar evolution of the stars in GCs, we ask whether or not deep internal mixing occurs in red giants or if in fact the compositions come from the primordial interstellar medium or previous generations of stars. It has been discovered that as a star evolves up the red giant branch, the surface carbon abundance decreases, which is evidence of deep internal mixing. We questioned whether these processes also affect O or Na abundance as a star evolves. We collected measurement data of red giants from GCs out of academic journals and sorted the data into catalogs. Then, we plotted the catalogs into figures, comparing surface O and Na each with stellar luminosity. Statistical tests were ran to quantify the amount of correlation between the variables. Out of 27 GCs, we concluded that eight show a positive correlation between Na and luminosity, and two show a negative correlation between O and luminosity. Properties of GCs were compared to determine if chemical distribution in stars depends on GCs as the self-enrichment scenario suggests. We created histograms of sodium distribution to test for bimodality to examine if there are separate trends in each GC. In six GCs, two different sequences of red giants appear for Na versus luminosity, suggesting evidence that the depth of mixing may differ among each red giant in a GC. This study has provided new evidence that the changing chemical abundances on the surfaces of red giants can be due to stellar evolutionary effects and deep internal mixing, which may not necessarily depend on the GC and may differ in depth among each red giant. Through this study, we learn more about stellar evolution which will eventually help us understand the origins of our universe. Most of this work was carried out by high school students working under the auspices of

  10. Ion beam effects on the surface and near-surface composition of TaSi2

    International Nuclear Information System (INIS)

    Valeri, S.; Di Bona, A.; Ottaviani, G.; Procop, M.

    1991-01-01

    Low-energy (0.7-4.5 keV) ion bombardment effects on polycrystalline TaSi 2 at sputter steady state and in various intermediate steps have been investigated, in the temperature range up to 550degC, to determine the time and temperature dependence of the altered layer formation. This in turn enables a better knowledge of the synergistic effects of the processes mentioned above. At low temperatures (T≤410degC) the surface is silicon depleted, and the depletion is even more severe in the subsurface region up to a depth of several tens of angstroems; silicon preferential sputtering and radiation-enhanced segregation assisted by the displacement mixing-induced motion of atoms are assumed to be responsible for this composition profile, while thermally activated diffusion processes become operative above 410degC, reducing progressively the concentration gradient between the surface and the subsurface zone. The composition at different depths has been determined from Auger peaks for different kinetic energies, by varying the take-off angle and finally by sputter profiling at low in energy the high energy processed surfaces. Quantitative analysis has been performed by XPS and AES by using the elemental standard method. (orig.)

  11. Sensor-Motor Maps for Describing Linear Reflex Composition in Hopping

    Directory of Open Access Journals (Sweden)

    Christian Schumacher

    2017-11-01

    Full Text Available In human and animal motor control several sensory organs contribute to a network of sensory pathways modulating the motion depending on the task and the phase of execution to generate daily motor tasks such as locomotion. To better understand the individual and joint contribution of reflex pathways in locomotor tasks, we developed a neuromuscular model that describes hopping movements. In this model, we consider the influence of proprioceptive length (LFB, velocity (VFB and force feedback (FFB pathways of a leg extensor muscle on hopping stability, performance and efficiency (metabolic effort. Therefore, we explore the space describing the blending of the monosynaptic reflex pathway gains. We call this reflex parameter space a sensor-motor map. The sensor-motor maps are used to visualize the functional contribution of sensory pathways in multisensory integration. We further evaluate the robustness of these sensor-motor maps to changes in tendon elasticity, body mass, segment length and ground compliance. The model predicted that different reflex pathway compositions selectively optimize specific hopping characteristics (e.g., performance and efficiency. Both FFB and LFB were pathways that enable hopping. FFB resulted in the largest hopping heights, LFB enhanced hopping efficiency and VFB had the ability to disable hopping. For the tested case, the topology of the sensor-motor maps as well as the location of functionally optimal compositions were invariant to changes in system designs (tendon elasticity, body mass, segment length or environmental parameters (ground compliance. Our results indicate that different feedback pathway compositions may serve different functional roles. The topology of the sensor-motor map was predicted to be robust against changes in the mechanical system design indicating that the reflex system can use different morphological designs, which does not apply for most robotic systems (for which the control often follows a

  12. Dipyridamole Body Surface Potential Mapping: Noninvasive Differentiation of Syndrome X from Coronary Artery Disease

    Czech Academy of Sciences Publication Activity Database

    Boudík, F.; Anger, Z.; Aschermann, M.; Vojáček, J.; Tomečková, Marie

    2002-01-01

    Roč. 35, č. 3 (2002), s. 181-191 ISSN 0022-0736 R&D Projects: GA MZd IZ4038 Keywords : body surface potential mapping * dipyridamole * coronary artery disease * syndrome X Subject RIV: BD - Theory of Information Impact factor: 0.599, year: 2002

  13. Creating surfactant nanoparticles for block copolymer composites through surface chemistry.

    Science.gov (United States)

    Kim, Bumjoon J; Bang, Joona; Hawker, Craig J; Chiu, Julia J; Pine, David J; Jang, Se Gyu; Yang, Seung-Man; Kramer, Edward J

    2007-12-04

    A simple strategy to tailor the surface of nanoparticles for their specific adsorption to and localization at block copolymer interfaces was explored. Gold nanoparticles coated by a mixture of low molecular weight thiol end-functional polystyrene (PS-SH) (Mn = 1.5 and 3.4 kg/mol) and poly(2-vinylpyridine) homopolymers (P2VP-SH) (Mn = 1.5 and 3.0 kg/mol) were incorporated into a lamellar poly(styrene-b-2-vinylpyridine) diblock copolymer (PS-b-P2VP) (Mn = 196 kg/mol). A library of nanoparticles with varying PS and P2VP surface compositions (FPS) and high polymer ligand areal chain densities was synthesized. The location of the nanoparticles in the PS-b-P2VP block copolymer was determined by transmission electron microscopy. Sharp transitions in particle location from the PS domain to the PS/P2VP interface, and subsequently to the P2VP domain, were observed at FPS = 0.9 and 0.1, respectively. This extremely wide window of FPS values where the polymer-coated gold nanoparticles adsorb to the interface suggests a redistribution of PS and P2VP polymers on the Au surface, inducing the formation of amphiphilic nanoparticles at the PS/P2VP interface. In a second and synthetically more challenging approach, gold nanoparticles were covered with a thiol terminated random copolymer of styrene and 2-vinylpyridine synthesized by RAFT polymerization. Two different random copolymers were considered, where the molecular weight was fixed at 3.5 kg/mol and the relative incorporation of styrene and 2-vinylpyridine repeat units varied (FPS = 0.52 and 0.40). The areal chain density of these random copolymers on Au is unfortunately not high enough to preclude any contact between the P2VP block of the block copolymer and the Au surface. Interestingly, gold nanoparticles coated by the random copolymer with FPS = 0.4 were dispersed in the P2VP domain, while those with FPS = 0.52 were located at the interface. A simple calculation for the adsorption energy to the interface of the nanoparticles

  14. Chemical, mechanical and biological properties of contemporary composite surface sealers.

    Science.gov (United States)

    Anagnostou, Maria; Mountouris, George; Silikas, Nick; Kletsas, Dimitris; Eliades, George

    2015-12-01

    To evaluate the chemical, mechanical, and biological properties of modern composite surface sealers (CSS) having different compositions. The CSS products tested were Biscover LV (BC), Durafinish (DF), G-Coat Plus (GC), and Permaseal (PS). The tests performed were: (A): degree of conversion (DC%) by ATR-FTIR spectroscopy; (B): thickness of O2-inhibition layer by transmission optical microscopy; (C): surface hardness, 10 min after irradiation and following 1 week water storage, employing a Vickers indenter (VHN); (D): color (ΔE*) and gloss changes (ΔGU) after toothbrush abrasion, using L*a*b* colorimetry and glossimetry; (E): accelerated wear (GC,PS only) by an OHSU wear simulator plus 3D profilometric analysis, and (F): cytotoxicity testing of aqueous CSS eluents on human gingival fibroblast cultures employing the methyl-(3)H thymidine DNA labeling method. Statistical analyses included 1-way (A, B, ΔE*, ΔGU) and 2-way (C, F) ANOVAs, plus Tukey post hoc tests. Student's t-test was used to evaluate the results of the accelerated wear test (α=0.05 for all). The rankings of the statistical significant differences were: (A) PS (64.9)>DF,BC,GC (56.1-53.9) DC%; (B) DF,PS (12.3,9.8)>GC,BC (5.2,4.8) μm; (C): GC (37.6)>BC,DF (32.6,31.1)>PS (26.6) VHN (10 min/dry) and BC,DF (29.3,28.7)>GC(26.5)>PS(21.6) VHN (1w/water), with no significant material/storage condition interaction; (D): no differences were found among GC,DF,BC,PS (0.67-1.11) ΔE*, with all values within the visually acceptable range and PS,BC (32.8,29.4)>GC,DF (19.4,12.9) ΔGU; (E): no differences were found between GC and PS in volume loss (0.10,0.11 mm(3)), maximum (113.9,130.5 μm) and mean wear depths (30.3,27.5 μm); (F): at 1% v/v concentration, DF showed toxicity (23% vital cells vs 95-102% for others). However, at 5% v/v concentration DF (0%) and BC (9%) were the most toxic, whereas GC (58%) and PS (56%) showed moderate toxicity. Important chemical, mechanical, and biological properties exist among

  15. Bedrock geology Forsmark. Modelling stage 2.3. Description of the bedrock geological map at the ground surface

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, Michael B.; Bergman, Torbjoern (Geological Survey of Sweden, Uppsala (Sweden)); Isaksson, Hans (GeoVista AB, Luleaa (Sweden)); Petersson, Jesper (SwedPower AB, Stockholm (Sweden))

    2008-12-15

    A description of the bedrock geological map of the ground surface at the Forsmark site is presented here. This map is essentially a 2D model for the distribution of different types of rock unit on this surface. Besides showing the distribution of these rock units, the bedrock geological map also displays the distribution of some deformation zones that intersect the ground surface. It also presents information bearing on the position and form of outcrops, the location and projection of boreholes drilled during the site investigation programme, subordinate rock types, the occurrence of abandoned mines or exploration prospects, measurements of ductile structures in outcrops, inferred form lines, key minerals, and the occurrence of mylonite and cataclastic rock. Bedrock data from outcrops and excavations, airborne and ground magnetic data and information from the uppermost part of boreholes have all been used in the construction of the geological map. The description has also made use of complementary analytical data bearing on the composition and age of the rocks as well gamma-ray spectrometry and gravity data. Uncertainty in the position of the boundaries between rock units over the mapped area are addressed in a qualitative manner. Four model versions of the bedrock geological map have been delivered to SKB's GIS database (bedrock geological map, Forsmark, versions 1.1, 1.2, 2.2 and 2.3) at different times during the site investigation programme. The Forsmark area is situated along the coast of the Baltic Sea in northern Uppland, Sweden, in a region where the overall level of ductile strain in the bedrock is high. This high-strain region extends several tens of kilometres across the WNW-ENE to NW-SE strike of the rocks in this part of the Fennoscandian Shield. At Forsmark, the coastal region is composed partly of high-strain belts, which formed under amphibolite-facies metamorphic conditions, and partly of tectonic lenses, where the bedrock is also affected by

  16. Bedrock geology Forsmark. Modelling stage 2.3. Description of the bedrock geological map at the ground surface

    International Nuclear Information System (INIS)

    Stephens, Michael B.; Bergman, Torbjoern; Isaksson, Hans; Petersson, Jesper

    2008-12-01

    A description of the bedrock geological map of the ground surface at the Forsmark site is presented here. This map is essentially a 2D model for the distribution of different types of rock unit on this surface. Besides showing the distribution of these rock units, the bedrock geological map also displays the distribution of some deformation zones that intersect the ground surface. It also presents information bearing on the position and form of outcrops, the location and projection of boreholes drilled during the site investigation programme, subordinate rock types, the occurrence of abandoned mines or exploration prospects, measurements of ductile structures in outcrops, inferred form lines, key minerals, and the occurrence of mylonite and cataclastic rock. Bedrock data from outcrops and excavations, airborne and ground magnetic data and information from the uppermost part of boreholes have all been used in the construction of the geological map. The description has also made use of complementary analytical data bearing on the composition and age of the rocks as well gamma-ray spectrometry and gravity data. Uncertainty in the position of the boundaries between rock units over the mapped area are addressed in a qualitative manner. Four model versions of the bedrock geological map have been delivered to SKB's GIS database (bedrock geological map, Forsmark, versions 1.1, 1.2, 2.2 and 2.3) at different times during the site investigation programme. The Forsmark area is situated along the coast of the Baltic Sea in northern Uppland, Sweden, in a region where the overall level of ductile strain in the bedrock is high. This high-strain region extends several tens of kilometres across the WNW-ENE to NW-SE strike of the rocks in this part of the Fennoscandian Shield. At Forsmark, the coastal region is composed partly of high-strain belts, which formed under amphibolite-facies metamorphic conditions, and partly of tectonic lenses, where the bedrock is also affected by

  17. Mapping Carrier Dynamics on Material Surfaces in Space and Time using Scanning Ultrafast Electron Microscopy

    KAUST Repository

    Sun, Jingya

    2016-02-25

    Selectively capturing the ultrafast dynamics of charge carriers on materials surfaces and at interfaces is crucial to the design of solar cells and optoelectronic devices. Despite extensive research efforts over the past few decades, information and understanding about surface-dynamical processes, including carrier trapping and recombination remains extremely limited. A key challenge is to selectively map such dynamic processes, a capability that is hitherto impractical by time-resolved laser techniques, which are limited by the laser’s relatively large penetration depth and consequently they record mainly bulk information. Such surface dynamics can only be mapped in real space and time by applying four-dimensional (4D) scanning ultrafast electron microscopy (S-UEM), which records snapshots of materials surfaces with nanometer spatial and sub-picosecond temporal resolutions. In this method, the secondary electron (SE) signal emitted from the sample’s surface is extremely sensitive to the surface dynamics and is detected in real time. In several unique applications, we spatially and temporally visualize the SE energy gain and loss, the charge carrier dynamics on the surface of InGaN nanowires and CdSe single crystals and its powder film. We also provide the mechanisms for the observed dynamics, which will be the foundation for future potential applications of S-UEM to a wide range of studies on material surfaces and device interfaces.

  18. Mapping Carrier Dynamics on Material Surfaces in Space and Time using Scanning Ultrafast Electron Microscopy

    KAUST Repository

    Sun, Jingya; Adhikari, Aniruddha; Shaheen, Basamat; Yang, Haoze; Mohammed, Omar F.

    2016-01-01

    Selectively capturing the ultrafast dynamics of charge carriers on materials surfaces and at interfaces is crucial to the design of solar cells and optoelectronic devices. Despite extensive research efforts over the past few decades, information and understanding about surface-dynamical processes, including carrier trapping and recombination remains extremely limited. A key challenge is to selectively map such dynamic processes, a capability that is hitherto impractical by time-resolved laser techniques, which are limited by the laser’s relatively large penetration depth and consequently they record mainly bulk information. Such surface dynamics can only be mapped in real space and time by applying four-dimensional (4D) scanning ultrafast electron microscopy (S-UEM), which records snapshots of materials surfaces with nanometer spatial and sub-picosecond temporal resolutions. In this method, the secondary electron (SE) signal emitted from the sample’s surface is extremely sensitive to the surface dynamics and is detected in real time. In several unique applications, we spatially and temporally visualize the SE energy gain and loss, the charge carrier dynamics on the surface of InGaN nanowires and CdSe single crystals and its powder film. We also provide the mechanisms for the observed dynamics, which will be the foundation for future potential applications of S-UEM to a wide range of studies on material surfaces and device interfaces.

  19. Active and Passive Remote Sensing Data Time Series for Flood Detection and Surface Water Mapping

    Science.gov (United States)

    Bioresita, Filsa; Puissant, Anne; Stumpf, André; Malet, Jean-Philippe

    2017-04-01

    As a consequence of environmental changes surface waters are undergoing changes in time and space. A better knowledge of the spatial and temporal distribution of surface waters resources becomes essential to support sustainable policies and development activities. Especially because surface waters, are not only a vital sweet water resource, but can also pose hazards to human settlements and infrastructures through flooding. Floods are a highly frequent disaster in the world and can caused huge material losses. Detecting and mapping their spatial distribution is fundamental to ascertain damages and for relief efforts. Spaceborne Synthetic Aperture Radar (SAR) is an effective way to monitor surface waters bodies over large areas since it provides excellent temporal coverage and, all-weather day-and-night imaging capabilities. However, emergent vegetation, trees, wind or flow turbulence can increase radar back-scatter returns and pose problems for the delineation of inundated areas. In such areas, passive remote sensing data can be used to identify vegetated areas and support the interpretation of SAR data. The availability of new Earth Observation products, for example Sentinel-1 (active) and Sentinel-2 (passive) imageries, with both high spatial and temporal resolution, have the potential to facilitate flood detection and monitoring of surface waters changes which are very dynamic in space and time. In this context, the research consists of two parts. In the first part, the objective is to propose generic and reproducible methodologies for the analysis of Sentinel-1 time series data for floods detection and surface waters mapping. The processing chain comprises a series of pre-processing steps and the statistical modeling of the pixel value distribution to produce probabilistic maps for the presence of surface waters. Images pre-processing for all Sentinel-1 images comprise the reduction SAR effect like orbit errors, speckle noise, and geometric effects. A modified

  20. Discrepancy between body surface area and body composition in cancer.

    Science.gov (United States)

    Stobäus, Nicole; Küpferling, Susanne; Lorenz, Marie-Luise; Norman, Kristina

    2013-01-01

    Calculation of cytostatic dose is typically based on body surface area (BSA) regardless of body composition. The aim of this study was to assess the discrepancy between BSA and low fat-free mass (FFM) by investigating the prevalence of low FFM with regard to BSA in 630 cancer patients. First, BSA was calculated according to DuBois and DuBois. Patients were divided into 6 categories with respect to their BSA. Each BSA category was further divided into 3 groups according to FFM: low (FFM), normal (-0.99 and 0.99 SD of mean FFM) or high (>1 SD of mean FFM), which was derived through bioelectric impedance analysis. FFM was reduced in 15.7% of patients, 69% had normal and 15.2% had high FFM. In patients with low FFM (i.e., more than-1 SD lower than the mean FFM within their BSA group), body mass index and fatigue were higher whereas functional status was reduced. Moreover, in the subcohort of patients receiving chemotherapy, absolute FFM [Hazard ratio (HR) = 0.970, P = 0.026] as well as the allocation to the low FFM group (HR = 1.644, P = 0.025) emerged as predictors of increased 1-yr mortality. In conclusion, there was a large discrepancy between FFM and BSA. Particularly women were affected by low FFM.

  1. Surface modified carbon nanoparticle papers and applications on polymer composites

    Science.gov (United States)

    Ouyang, Xilian

    Free-standing paper like materials are usually employed as protective layers, chemical filters, components of electrical batteries or supercapacitors, adhesive layers, and electronic or optoelectric components. Free-standing papers made from carbon nanoparticles have drawn increased interest because they have a variety of superior chemical and physical characteristics, such as light weight, high intrinsic mechanical properties, and extraordinary high electrical conductivity. Nanopapers fabricated from 1- D shape carbon nanofibers (CNFs) and carbon nanotubes (CNTs) are promising reinforcing materials for polymer composites, because the highly porous CNF and CNT nanopapers (porosity ˜80% and ˜70% respectively) can be impregnated with matrix polymers. In the first part of this work, polyaniline (PANI) was used to functionalize the surface of CNFs, and the resultant carbon nanopapers presented impressive mechanical strength and electrical conductivity that it could be used in the in-mold coating (IMC)/ injection molding process to achieve high electromagnetic interference (EMI) shielding effectiveness. Aniline modified (AF) CNT nanopapers were used as a 3D network in gas separation membranes. The resultant composite membranes demonstrated better and stable CO2 permeance and CO 2/H2 selectivity in a high temperature (107°C) and high pressure (15-30 atm) gas separation process, not achievable by conventional polymer membranes. In the second part, we demonstrated that 2-D graphene (GP) or graphene oxide (GO) nanosheets could be tightly packed into a film which was impermeable to most gases and liquids. GP or GO nanopapers could be coated on polymer composites. In order to achieve well-dispersed single-layer graphene in aqueous medium, we developed a facile approach to synthesize functional GP bearing benzenesulfonic acid groups which allow the preparation of nanopapers by water based assembly. With the optimized processing conditions, our best GP nanopapers could reach

  2. Globalland30 Mapping Capacity of Land Surface Water in Thessaly, Greece

    Directory of Open Access Journals (Sweden)

    Ioannis Manakos

    2014-12-01

    Full Text Available The National Geomatics Center of China (NGCC produced Global Land Cover (GlobalLand30 maps with 30 m spatial resolution for the years 2000 and 2009–2010, responding to the need for harmonized, accurate, and high-resolution global land cover data. This study aims to assess the mapping accuracy of the land surface water layer of GlobalLand30 for 2009–2010. A representative Mediterranean region, situated in Greece, is considered as the case study area, with 2009 as the reference year. The assessment is realized through an object-based comparison of the GlobalLand30 water layer with the ground truth and visually interpreted data from the Hellenic Cadastre fine spatial resolution (0.5 m orthophoto map layer. GlobCover 2009, GlobCorine 2009, and GLCNMO 2008 corresponding thematic layers are utilized to show and quantify the progress brought along with the increment of the spatial resolution, from 500 m to 300 m and finally to 30 m with the newly produced GlobalLand30 maps. GlobalLand30 detected land surface water areas show a 91.9% overlap with the reference data, while the coarser resolution products are restricted to lower accuracies. Validation is extended to the drainage network elements, i.e., rivers and streams, where GlobalLand30 outperforms the other global map products, as well.

  3. Surface materials map of Afghanistan: iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Kokaly, Raymond F.; Hoefen, Todd M.; Dudek, Kathleen B.; Livo, Keith E.

    2012-01-01

    This map shows the distribution of selected iron-bearing minerals and other materials derived from analysis of HyMap imaging spectrometer data of Afghanistan. Using a NASA (National Aeronautics and Space Administration) WB-57 aircraft flown at an altitude of ~15,240 meters or ~50,000 feet, 218 flight lines of data were collected over Afghanistan between August 22 and October 2, 2007. The HyMap data were converted to apparent surface reflectance, then further empirically adjusted using ground-based reflectance measurements. The reflectance spectrum of each pixel of HyMap data was compared to the spectral features of reference entries in a spectral library of minerals, vegetation, water, ice, and snow. This map shows the spatial distribution of iron-bearing minerals and other materials having diagnostic absorptions at visible and near-infrared wavelengths. These absorptions result from electronic processes in the minerals. Several criteria, including (1) the reliability of detection and discrimination of minerals using the HyMap spectrometer data, (2) the relative abundance of minerals, and (3) the importance of particular minerals to studies of Afghanistan's natural resources, guided the selection of entries in the reference spectral library and, therefore, guided the selection of mineral classes shown on this map. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated. Minerals having similar spectral features were less easily discriminated, especially where the minerals were not particularly abundant and (or) where vegetation cover reduced the absorption strength of mineral features. Complications in reflectance calibration also affected the detection and identification of minerals.

  4. Surface materials map of Afghanistan: carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Dudek, Kathleen B.; Livo, Keith E.

    2012-01-01

    This map shows the distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of HyMap imaging spectrometer data of Afghanistan. Using a NASA (National Aeronautics and Space Administration) WB-57 aircraft flown at an altitude of ~15,240 meters or ~50,000 feet, 218 flight lines of data were collected over Afghanistan between August 22 and October 2, 2007. The HyMap data were converted to apparent surface reflectance, then further empirically adjusted using ground-based reflectance measurements. The reflectance spectrum of each pixel of HyMap data was compared to the spectral features of reference entries in a spectral library of minerals, vegetation, water, ice, and snow. This map shows the spatial distribution of minerals that have diagnostic absorption features in the shortwave infrared wavelengths. These absorption features result primarily from characteristic chemical bonds and mineralogical vibrations. Several criteria, including (1) the reliability of detection and discrimination of minerals using the HyMap spectrometer data, (2) the relative abundance of minerals, and (3) the importance of particular minerals to studies of Afghanistan's natural resources, guided the selection of entries in the reference spectral library and, therefore, guided the selection of mineral classes shown on this map. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated. Minerals having similar spectral features were less easily discriminated, especially where the minerals were not particularly abundant and (or) where vegetation cover reduced the absorption strength of mineral features. Complications in reflectance calibration also affected the detection and identification of minerals.

  5. GIS based optimal impervious surface map generation using various spatial data for urban nonpoint source management.

    Science.gov (United States)

    Lee, Cholyoung; Kim, Kyehyun; Lee, Hyuk

    2018-01-15

    Impervious surfaces are mainly artificial structures such as rooftops, roads, and parking lots that are covered by impenetrable materials. These surfaces are becoming the major causes of nonpoint source (NPS) pollution in urban areas. The rapid progress of urban development is increasing the total amount of impervious surfaces and NPS pollution. Therefore, many cities worldwide have adopted a stormwater utility fee (SUF) that generates funds needed to manage NPS pollution. The amount of SUF is estimated based on the impervious ratio, which is calculated by dividing the total impervious surface area by the net area of an individual land parcel. Hence, in order to identify the exact impervious ratio, large-scale impervious surface maps (ISMs) are necessary. This study proposes and assesses various methods for generating large-scale ISMs for urban areas by using existing GIS data. Bupyeong-gu, a district in the city of Incheon, South Korea, was selected as the study area. Spatial data that were freely offered by national/local governments in S. Korea were collected. First, three types of ISMs were generated by using the land-cover map, digital topographic map, and orthophotographs, to validate three methods that had been proposed conceptually by Korea Environment Corporation. Then, to generate an ISM of higher accuracy, an integration method using all data was proposed. Error matrices were made and Kappa statistics were calculated to evaluate the accuracy. Overlay analyses were performed to examine the distribution of misclassified areas. From the results, the integration method delivered the highest accuracy (Kappa statistic of 0.99) compared to the three methods that use a single type of spatial data. However, a longer production time and higher cost were limiting factors. Among the three methods using a single type of data, the land-cover map showed the highest accuracy with a Kappa statistic of 0.91. Thus, it was judged that the mapping method using the land

  6. Adhesion enhancement of Al coatings on carbon/epoxy composite surfaces by atmospheric plasma

    International Nuclear Information System (INIS)

    Coulon, J.F.; Tournerie, N.; Maillard, H.

    2013-01-01

    Adhesion strengths between aluminium thin film coatings and manufactured carbon/epoxy composite surfaces were measured by assessing fracture tensile strengths using pull-off tests. The effect of the substrate roughness (nm to μm) of these composite surfaces on adhesion was studied by examining the surface free energies and adhesion strengths. The adhesion strengths of the coatings varied significantly. To improve the coating adhesion, each composite surface was treated with atmospheric plasma prior to deposition, which resulted in an increase in the surface free energy from approximately 40 mJ/m 2 to 70 mJ/m 2 because the plasma pretreatment led to the formation of hydrophilic C-O and C=O bonds on the composite surfaces, as demonstrated by X-ray photoelectron spectroscopy analyses. The adhesion strengths of the coatings were enhanced for all surface roughnesses studied. In our study, the effect of mechanical adhesion due to roughness was separated from the effect of modifying the chemical bonds with plasma activation. The adhesion ability of the pure resin was relatively weak. Increasing the surface roughness largely improved the adhesion of the resin surface. Plasma treatment of the pure resin also increased the surface adhesion. Our study shows that plasma activation effectively enhances the adhesion of manufactured composites, even when the surface roughness is on the order of microns. The ageing of the surface activation was also investigated, and the results demonstrate that atmospheric plasma has potential for use in the pretreatment of composite materials.

  7. Mapping soil organic carbon content and composition across Australia to assess vulnerability to climate change

    Science.gov (United States)

    Viscarra Rossel, R. A.

    2015-12-01

    We can effectively monitor soil condition—and develop sound policies to offset the emissions of greenhouse gases—only with accurate data from which to define baselines. Currently, estimates of soil organic C for countries or continents are either unavailable or largely uncertain because they are derived from sparse data, with large gaps over many areas of the Earth. Here, we derive spatially explicit estimates, and their uncertainty, of the distribution and stock of organic C content and composition in the soil of Australia. The composition of soil organic C may be characterized by chemical separation or physical fractionation based on either particle size or particle density (Skjemstad et al., 2004; Gregorich et al., 2006; Kelleher&Simpson, 2006; Zimmermann et al., 2007). In Australia, for example, Skjemstad et al. (2004) used physical separation of soil samples into 50-2000 and solid-state 13C nuclear magnetic resonance (NMR) spectroscopy, giving the three OC pools, particulate organic carbon (POC), humic organic carbon (HOC) and resistant organic carbon (ROC; charcoal or char-carbon). We assembled and harmonized data from several sources to produce the most comprehensive set of data on the current stock of organic C in soil of the continent. Using them, we have produced a fine spatial resolution baseline map of organic C, POC, HOC and ROC at the continental scale. In this presentation I will describe how we made the maps and how we use them to assess the vulnerability of soil organic C to for instance climate change.

  8. Saturation Recovery Myocardial T1 Mapping with a Composite Radiofrequency Pulse on a 3T MR Imaging System.

    Science.gov (United States)

    Morita, Kosuke; Oda, Seitaro; Utsunomiya, Daisuke; Nakaura, Takeshi; Matsubara, Takatoshi; Goto, Makoto; Okuaki, Tomoyuki; Yuki, Hideaki; Nagayama, Yasunori; Kidoh, Masafumi; Hirata, Kenichiro; Iyama, Yuij; Taguchi, Narumi; Hatemura, Masahiro; Hashida, Masahiro; Yamashita, Yasuyuki

    2018-01-10

    To evaluate the effect of a composite radiofrequency (RF) pulse on saturation recovery (SR) myocardial T 1 mapping using a 3T MR system. Phantom and in vivo studies were performed with a clinical 3T MR scanner. Accuracy and reproducibility of the SR T 1 mapping using conventional and composite RF pulses were first compared in phantom experiments. An in vivo study was performed of 10 healthy volunteers who were imaged with conventional and composite RF pulse methods twice each. In vivo reproducibility of myocardial T 1 value and the inter-segment variability were assessed. The phantom study revealed significant differences in the mean T 1 values between the two methods, and the reproducibility for the composite RF pulse was significantly smaller than that for the conventional RF pulse. For both methods, the correlations of the reference and measured T 1 values were excellent (r 2 = 0.97 and 0.98 for conventional and composite RF pulses, respectively). The in vivo study showed that the mean T 1 value for composite RF pulse was slightly lower than that for conventional RF pulse, but this difference was not significant (P = 0.06). The inter-segment variability for the composite RF pulse was significantly smaller than that for conventional RF pulse (P composite RF pulses (r = 0.83 and 0.29, respectively). SR T 1 mapping using composite RF pulse provides accurate quantification of T 1 values and can lessen measurement variability and enable reproducible T 1 measurements.

  9. Wide-Baseline Stereo-Based Obstacle Mapping for Unmanned Surface Vehicles

    Science.gov (United States)

    Mou, Xiaozheng; Wang, Han

    2018-01-01

    This paper proposes a wide-baseline stereo-based static obstacle mapping approach for unmanned surface vehicles (USVs). The proposed approach eliminates the complicated calibration work and the bulky rig in our previous binocular stereo system, and raises the ranging ability from 500 to 1000 m with a even larger baseline obtained from the motion of USVs. Integrating a monocular camera with GPS and compass information in this proposed system, the world locations of the detected static obstacles are reconstructed while the USV is traveling, and an obstacle map is then built. To achieve more accurate and robust performance, multiple pairs of frames are leveraged to synthesize the final reconstruction results in a weighting model. Experimental results based on our own dataset demonstrate the high efficiency of our system. To the best of our knowledge, we are the first to address the task of wide-baseline stereo-based obstacle mapping in a maritime environment. PMID:29617293

  10. Riemannian metric optimization on surfaces (RMOS) for intrinsic brain mapping in the Laplace-Beltrami embedding space.

    Science.gov (United States)

    Gahm, Jin Kyu; Shi, Yonggang

    2018-05-01

    Surface mapping methods play an important role in various brain imaging studies from tracking the maturation of adolescent brains to mapping gray matter atrophy patterns in Alzheimer's disease. Popular surface mapping approaches based on spherical registration, however, have inherent numerical limitations when severe metric distortions are present during the spherical parameterization step. In this paper, we propose a novel computational framework for intrinsic surface mapping in the Laplace-Beltrami (LB) embedding space based on Riemannian metric optimization on surfaces (RMOS). Given a diffeomorphism between two surfaces, an isometry can be defined using the pullback metric, which in turn results in identical LB embeddings from the two surfaces. The proposed RMOS approach builds upon this mathematical foundation and achieves general feature-driven surface mapping in the LB embedding space by iteratively optimizing the Riemannian metric defined on the edges of triangular meshes. At the core of our framework is an optimization engine that converts an energy function for surface mapping into a distance measure in the LB embedding space, which can be effectively optimized using gradients of the LB eigen-system with respect to the Riemannian metrics. In the experimental results, we compare the RMOS algorithm with spherical registration using large-scale brain imaging data, and show that RMOS achieves superior performance in the prediction of hippocampal subfields and cortical gyral labels, and the holistic mapping of striatal surfaces for the construction of a striatal connectivity atlas from substantia nigra. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. The Sloan Digital Sky Survey Reverberation Mapping Project: Composite Lags at z ≤ 1

    Science.gov (United States)

    Li, Jennifer; Shen, Yue; Horne, Keith; Brandt, W. N.; Greene, Jenny E.; Grier, C. J.; Ho, Luis C.; Kochanek, Chris; Schneider, Donald P.; Trump, Jonathan R.; Dawson, Kyle S.; Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena

    2017-09-01

    We present composite broad-line region (BLR) reverberation mapping lag measurements for Hα, Hβ, He II λ4686, and Mg II for a sample of 144, z ≲ 1 quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Using only the 32-epoch spectroscopic light curves in the first six-month season of SDSS-RM observations, we compile correlation function measurements for individual objects and then coadd them to allow the measurement of the average lags for our sample at mean redshifts of 0.4 (for Hα) and ˜0.65 (for the other lines). At similar quasar luminosities and redshifts, the sample-averaged lag decreases in the order of Mg II, Hα, Hβ, and He II. This decrease in lags is accompanied by an increase in the mean line width of the four lines, and is roughly consistent with the virialized motion for BLR gas in photoionization equilibrium. These are among the first RM measurements of stratified BLR structure at z > 0.3. Dividing our sample by luminosity, Hα shows clear evidence of increasing lags with luminosity, consistent with the expectation from the measured BLR size-luminosity relation based on Hβ. The other three lines do not show a clear luminosity trend in their average lags due to the limited dynamic range of luminosity probed and the poor average correlation signals in the divided samples, a situation that will be improved with the incorporation of additional photometric and spectroscopic data from SDSS-RM. We discuss the utility and caveats of composite lag measurements for large statistical quasar samples with reverberation mapping data.

  12. The Sloan Digital Sky Survey Reverberation Mapping Project: Composite Lags at z ≤ 1

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jennifer; Shen, Yue [Department of Astronomy, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Horne, Keith [SUPA Physics/Astronomy, Univ. of St. Andrews, St. Andrews KY16 9SS (United Kingdom); Brandt, W. N.; Grier, C. J.; Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA, 16802 (United States); Greene, Jenny E. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Ho, Luis C. [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China); Kochanek, Chris [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Trump, Jonathan R. [Department of Physics, University of Connecticut, 2152 Hillside Road, Unit 3046, Storrs, CT 06269 (United States); Dawson, Kyle S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena [Apache Point Observatory and New Mexico State University, P.O. Box 59, Sunspot, NM, 88349-0059 (United States)

    2017-09-01

    We present composite broad-line region (BLR) reverberation mapping lag measurements for H α , H β , He ii λ 4686, and Mg ii for a sample of 144, z ≲ 1 quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Using only the 32-epoch spectroscopic light curves in the first six-month season of SDSS-RM observations, we compile correlation function measurements for individual objects and then coadd them to allow the measurement of the average lags for our sample at mean redshifts of 0.4 (for H α ) and ∼0.65 (for the other lines). At similar quasar luminosities and redshifts, the sample-averaged lag decreases in the order of Mg ii, H α , H β , and He ii. This decrease in lags is accompanied by an increase in the mean line width of the four lines, and is roughly consistent with the virialized motion for BLR gas in photoionization equilibrium. These are among the first RM measurements of stratified BLR structure at z > 0.3. Dividing our sample by luminosity, H α shows clear evidence of increasing lags with luminosity, consistent with the expectation from the measured BLR size–luminosity relation based on H β . The other three lines do not show a clear luminosity trend in their average lags due to the limited dynamic range of luminosity probed and the poor average correlation signals in the divided samples, a situation that will be improved with the incorporation of additional photometric and spectroscopic data from SDSS-RM. We discuss the utility and caveats of composite lag measurements for large statistical quasar samples with reverberation mapping data.

  13. The Sloan Digital Sky Survey Reverberation Mapping Project: Composite Lags at z ≤ 1

    International Nuclear Information System (INIS)

    Li, Jennifer; Shen, Yue; Horne, Keith; Brandt, W. N.; Grier, C. J.; Schneider, Donald P.; Greene, Jenny E.; Ho, Luis C.; Kochanek, Chris; Trump, Jonathan R.; Dawson, Kyle S.; Pan, Kaike; Bizyaev, Dmitry; Oravetz, Daniel; Simmons, Audrey; Malanushenko, Elena

    2017-01-01

    We present composite broad-line region (BLR) reverberation mapping lag measurements for H α , H β , He ii λ 4686, and Mg ii for a sample of 144, z ≲ 1 quasars from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project. Using only the 32-epoch spectroscopic light curves in the first six-month season of SDSS-RM observations, we compile correlation function measurements for individual objects and then coadd them to allow the measurement of the average lags for our sample at mean redshifts of 0.4 (for H α ) and ∼0.65 (for the other lines). At similar quasar luminosities and redshifts, the sample-averaged lag decreases in the order of Mg ii, H α , H β , and He ii. This decrease in lags is accompanied by an increase in the mean line width of the four lines, and is roughly consistent with the virialized motion for BLR gas in photoionization equilibrium. These are among the first RM measurements of stratified BLR structure at z > 0.3. Dividing our sample by luminosity, H α shows clear evidence of increasing lags with luminosity, consistent with the expectation from the measured BLR size–luminosity relation based on H β . The other three lines do not show a clear luminosity trend in their average lags due to the limited dynamic range of luminosity probed and the poor average correlation signals in the divided samples, a situation that will be improved with the incorporation of additional photometric and spectroscopic data from SDSS-RM. We discuss the utility and caveats of composite lag measurements for large statistical quasar samples with reverberation mapping data.

  14. A mechanical model for surface layer formation on self-lubricating ceramic composites

    NARCIS (Netherlands)

    Song, Jiupeng; Valefi, Mahdiar; de Rooij, Matthias B.; Schipper, Dirk J.

    2010-01-01

    To predict the thickness of a self-lubricating layer on the contact surface of ceramic composite material containing a soft phase during dry sliding test, a mechanical model was built to calculate the material transfer of the soft second phase in the composite to the surface. The tribological test,

  15. Influence of surface roughness on streptococcal adhesion forces to composite resins

    NARCIS (Netherlands)

    Mei, Li; Busscher, Henk J; van der Mei, Henny C; Ren, Yijin

    OBJECTIVE: To determine streptococcal adhesion forces with composite resins with different surface roughness. METHODS: Polishing and grinding were applied to obtain smooth (roughness 20 nm), moderately rough (150 nm) and rough (350 nm) surfaces of two orthodontic, light-cured composites. Adhesion

  16. Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy

    DEFF Research Database (Denmark)

    Klausen, Lasse Hyldgaard; Fuhs, Thomas; Dong, Mingdong

    2016-01-01

    Local surface charge density of lipid membranes influences membrane-protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far...

  17. Influence of Layup Sequence on the Surface Accuracy of Carbon Fiber Composite Space Mirrors

    Science.gov (United States)

    Yang, Zhiyong; Liu, Qingnian; Zhang, Boming; Xu, Liang; Tang, Zhanwen; Xie, Yongjie

    2018-04-01

    Layup sequence is directly related to stiffness and deformation resistance of the composite space mirror, and error caused by layup sequence can affect the surface precision of composite mirrors evidently. Variation of layup sequence with the same total thickness of composite space mirror changes surface form of the composite mirror, which is the focus of our study. In our research, the influence of varied quasi-isotropic stacking sequences and random angular deviation on the surface accuracy of composite space mirrors was investigated through finite element analyses (FEA). We established a simulation model for the studied concave mirror with 500 mm diameter, essential factors of layup sequences and random angular deviations on different plies were discussed. Five guiding findings were described in this study. Increasing total plies, optimizing stacking sequence and keeping consistency of ply alignment in ply placement are effective to improve surface accuracy of composite mirror.

  18. Determination of planetary surfaces elemental composition by gamma and neutron spectroscopy

    International Nuclear Information System (INIS)

    Diez, B.

    2009-06-01

    Measuring the neutron and gamma ray fluxes produced by the interaction of galactic cosmic rays with planetary surfaces allow constraining the chemical composition of the upper tens of centimeters of material. Two different angles are proposed to study neutron and gamma spectroscopy: data processing and data interpretation. The present work is in line with two experiments, the Mars Odyssey Neutron Spectrometer (MONS) and the Selene Gamma Ray Spectrometer. A review of the processing operations applied to the MONS dataset is proposed. The resulting dataset is used to determine the depth of the hydrogen deposits below the Martian surface. In water depleted regions, neutron data allow constraining the concentration in elements likely to interact with neutrons. The confrontation of these results to those issued from the Gamma Ray Spectrometer onboard Mars Odyssey provides interesting insight on the geologic context of the Central Elysium Planitia region. These martian questions are followed by the study of the Selene gamma ray data. Although only preliminary processing has been done to date, qualitative lunar maps of major elements (Fe, Ca, Si, Ti, Mg, K, Th, U) have already been realized. (author)

  19. Surface strain rate colour map of the Tatra Mountains region (Slovakia based on GNSS data

    Directory of Open Access Journals (Sweden)

    Bednárik Martin

    2016-12-01

    Full Text Available The surface deformation of the Tatra Mountains region in Western Carpathians can nowadays be studied directly thanks to precise geodetic measurements using the GNSS. The strain or stress tensor field is, however, a rather complex “data structure” difficult to present legibly and with sufficient resolution in the form of a classical map. A novel and promising approach to the solution of this problem is coding the three principal strain or stress values into the three colour channels (red, green, blue of an RGB colour. In our previous study, the colour depended on the stress tensor shape descriptors. In the current study, the adapted colouring scheme uses a subset of shape descriptors common to stress and strain, which differ only in the scaling factor. In this manner, we generate the colour map of the surface strain rate field, where the colour of each grid point carries the information about the shape of the strain rate tensor at that point. The resulting strain rate colour map can be displayed simultaneously with the map of the faults or elevations and be easily checked for the data or interpolation method errors and incompatibility with the geophysical and geological expectations.

  20. Mapping soil particle-size fractions: A comparison of compositional kriging and log-ratio kriging

    Science.gov (United States)

    Wang, Zong; Shi, Wenjiao

    2017-03-01

    Soil particle-size fractions (psf) as basic physical variables need to be accurately predicted for regional hydrological, ecological, geological, agricultural and environmental studies frequently. Some methods had been proposed to interpolate the spatial distributions of soil psf, but the performance of compositional kriging and different log-ratio kriging methods is still unclear. Four log-ratio transformations, including additive log-ratio (alr), centered log-ratio (clr), isometric log-ratio (ilr), and symmetry log-ratio (slr), combined with ordinary kriging (log-ratio kriging: alr_OK, clr_OK, ilr_OK and slr_OK) were selected to be compared with compositional kriging (CK) for the spatial prediction of soil psf in Tianlaochi of Heihe River Basin, China. Root mean squared error (RMSE), Aitchison's distance (AD), standardized residual sum of squares (STRESS) and right ratio of the predicted soil texture types (RR) were chosen to evaluate the accuracy for different interpolators. The results showed that CK had a better accuracy than the four log-ratio kriging methods. The RMSE (sand, 9.27%; silt, 7.67%; clay, 4.17%), AD (0.45), STRESS (0.60) of CK were the lowest and the RR (58.65%) was the highest in the five interpolators. The clr_OK achieved relatively better performance than the other log-ratio kriging methods. In addition, CK presented reasonable and smooth transition on mapping soil psf according to the environmental factors. The study gives insights for mapping soil psf accurately by comparing different methods for compositional data interpolation. Further researches of methods combined with ancillary variables are needed to be implemented to improve the interpolation performance.

  1. Note: Electron energy spectroscopy mapping of surface with scanning tunneling microscope.

    Science.gov (United States)

    Li, Meng; Xu, Chunkai; Zhang, Panke; Li, Zhean; Chen, Xiangjun

    2016-08-01

    We report a novel scanning probe electron energy spectrometer (SPEES) which combines a double toroidal analyzer with a scanning tunneling microscope to achieve both topography imaging and electron energy spectroscopy mapping of surface in situ. The spatial resolution of spectroscopy mapping is determined to be better than 0.7 ± 0.2 μm at a tip sample distance of 7 μm. Meanwhile, the size of the field emission electron beam spot on the surface is also measured, and is about 3.6 ± 0.8 μm in diameter. This unambiguously demonstrates that the spatial resolution of SPEES technique can be much better than the size of the incident electron beam.

  2. Note: Electron energy spectroscopy mapping of surface with scanning tunneling microscope

    Energy Technology Data Exchange (ETDEWEB)

    Li, Meng; Xu, Chunkai, E-mail: xuck@ustc.edu.cn, E-mail: xjun@ustc.edu.cn; Zhang, Panke; Li, Zhean; Chen, Xiangjun, E-mail: xuck@ustc.edu.cn, E-mail: xjun@ustc.edu.cn [Hefei National Laboratory for Physical Science at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026 (China)

    2016-08-15

    We report a novel scanning probe electron energy spectrometer (SPEES) which combines a double toroidal analyzer with a scanning tunneling microscope to achieve both topography imaging and electron energy spectroscopy mapping of surface in situ. The spatial resolution of spectroscopy mapping is determined to be better than 0.7 ± 0.2 μm at a tip sample distance of 7 μm. Meanwhile, the size of the field emission electron beam spot on the surface is also measured, and is about 3.6 ± 0.8 μm in diameter. This unambiguously demonstrates that the spatial resolution of SPEES technique can be much better than the size of the incident electron beam.

  3. Note: Electron energy spectroscopy mapping of surface with scanning tunneling microscope

    International Nuclear Information System (INIS)

    Li, Meng; Xu, Chunkai; Zhang, Panke; Li, Zhean; Chen, Xiangjun

    2016-01-01

    We report a novel scanning probe electron energy spectrometer (SPEES) which combines a double toroidal analyzer with a scanning tunneling microscope to achieve both topography imaging and electron energy spectroscopy mapping of surface in situ. The spatial resolution of spectroscopy mapping is determined to be better than 0.7 ± 0.2 μm at a tip sample distance of 7 μm. Meanwhile, the size of the field emission electron beam spot on the surface is also measured, and is about 3.6 ± 0.8 μm in diameter. This unambiguously demonstrates that the spatial resolution of SPEES technique can be much better than the size of the incident electron beam.

  4. Mapping lichen color-groups in western Arctic Alaska using seasonal Landsat composites

    Science.gov (United States)

    Nelson, P.; Macander, M. J.; Swingley, C. S.

    2016-12-01

    Mapping lichens at a landscape scale has received increased recent interest due to fears that terricolous lichen mats, primary winter caribou forage, may be decreasing across the arctic and boreal zones. However, previous efforts have produced taxonomically coarse, total lichen cover maps or have covered relatively small spatial extents. Here we attempt to map lichens of differing colors as species proxies across northwestern Alaska to produce the finest taxonomic and spatial- grained lichen maps covering the largest spatial extent to date. Lichen community sampling in five western Alaskan National Parks and Preserves from 2007-2012 generated 328 FIA-style 34.7 m radius plots on which species-level macrolichen community structure and abundance was estimated. Species were coded by color and plot lichen cover was aggregated by plot as the sum of the cover of each species in a color group. Ten different lichen color groupings were used for modeling to deduce which colors were most detectable. Reflectance signatures of each plot were extracted from a series of Landsat composites (circa 2000-2010) partitioned into two-week intervals from June 1 to Sept. 15. Median reflectance values for each band in each pixel were selected based on filtering criteria to reduce likelihood of snow cover. Lichen color group cover was regressed against plot reflectance plus additional abiotic predictors in two different data mining algorithms. Brown and grey lichens had the best models explaining approximately 40% of lichen cover in those color groups. Both data mining techniques produced similarly good fitting models. Spatial patterns of lichen color-group cover show distinctly different ecological patterns of these color-group species proxies.

  5. A Novel Sensory Mapping Design for Bipedal Walking on a Sloped Surface

    Directory of Open Access Journals (Sweden)

    Chiao-Min Wu

    2012-10-01

    Full Text Available This paper presents an environment recognition method for bipedal robots using a time-delay neural network. For a robot to walk in a varying terrain, it is desirable that the robot can adapt to any environment encountered in real-time. This paper aims to develop a sensory mapping unit to recognize environment types from the input sensory data based on an artificial neural network approach. With the proposed sensory mapping design, a bipedal walking robot can obtain real-time environment information and select an appropriate walking pattern accordingly. Due to the time-dependent property of sensory data, the sensory mapping is realized by using a time-delay neural network. The sensory data of earlier time sequences combined with current sensory data are sent to the neural network. The proposed method has been implemented on the humanoid robot NAO for verification. Several interesting experiments were carried out to verify the effectiveness of the sensory mapping design. The mapping design is validated for the uphill, downhill and flat surface cases, where three types of environment can be recognized by the NAO robot online.

  6. LRO Lyman Alpha Mapping Project (LAMP) Far-UV Investigations of Lunar Composition, Porosity, and Space Weathering

    Science.gov (United States)

    Retherford, K. D.; Greathouse, T. K.; Mandt, K. E.; Gladstone, R.; Hendrix, A.; Cahill, J. T.; Liu, Y.; Grava, C.; Hurley, D.; Egan, A.; Kaufmann, D. E.; Raut, U.; Byron, B. D.; Magana, L. O.; Stickle, A. M.; Wyrick, D. Y.; Pryor, W. R.

    2017-12-01

    Far ultraviolet reflectance measurements of the Moon, icy satellites, comets, and asteroids have proven surprisingly useful for advancing our understanding of planetary surfaces. This new appreciation for planetary far-UV imaging spectroscopy is provided in large part thanks to nearly a decade of investigations with the Lunar Reconnaissance Orbiter (LRO) Lyman Alpha Mapping Project (LAMP). LAMP has demonstrated an innovative nightside observing technique, putting a new light on permanently shadowed regions (PSRs) and other features on the Moon. Dayside far-UV albedo maps complement the nightside data, enabling comparisons of direct and hemispheric (diffuse) illumination derived albedos. We'll discuss the strengths of the far-UV reflectance imaging spectroscopy technique with respect to several new LAMP results. Detections of water frost and hydration signatures near 165 nm, for example, provide constraints on composition that complement infrared spectroscopy, visible imaging, neutron spectroscopy, radar, and other techniques. LRO's polar orbit and high data downlink capabilities enable searches for diurnal variations in spectral signals. At far-UV wavelengths a relatively blue spectral slope is diagnostic of space weathering, which is opposite of the spectral reddening indicator of maturity at wavelengths longward of 180 nm. By utilizing natural diffuse illumination sources on the nightside the far-UV technique is able to identify relative increases in porosity within the PSRs, and provides an additional tool for determining relative surface ages. On October 6, 2016 LAMP enacted a new, more sensitive dayside operating mode that expands its ability to search for diurnally varying hydration signals associated with different regions and features.

  7. Mapping Surface Broadband Albedo from Satellite Observations: A Review of Literatures on Algorithms and Products

    Directory of Open Access Journals (Sweden)

    Ying Qu

    2015-01-01

    Full Text Available Surface albedo is one of the key controlling geophysical parameters in the surface energy budget studies, and its temporal and spatial variation is closely related to the global climate change and regional weather system due to the albedo feedback mechanism. As an efficient tool for monitoring the surfaces of the Earth, remote sensing is widely used for deriving long-term surface broadband albedo with various geostationary and polar-orbit satellite platforms in recent decades. Moreover, the algorithms for estimating surface broadband albedo from satellite observations, including narrow-to-broadband conversions, bidirectional reflectance distribution function (BRDF angular modeling, direct-estimation algorithm and the algorithms for estimating albedo from geostationary satellite data, are developed and improved. In this paper, we present a comprehensive literature review on algorithms and products for mapping surface broadband albedo with satellite observations and provide a discussion of different algorithms and products in a historical perspective based on citation analysis of the published literature. This paper shows that the observation technologies and accuracy requirement of applications are important, and long-term, global fully-covered (including land, ocean, and sea-ice surfaces, gap-free, surface broadband albedo products with higher spatial and temporal resolution are required for climate change, surface energy budget, and hydrological studies.

  8. Adhesion mapping of chemically modified and poly(ethylene oxide)-grafted glass surfaces.

    Science.gov (United States)

    Jogikalmath, G; Stuart, J K; Pungor, A; Hlady, V

    1999-08-01

    Two-dimensional mapping of the adhesion pull-off forces was used to study the origin of surface heterogeneity in the grafted poly(ethylene oxide) (PEO) layer. The variance of the pull-off forces measured over the μm-sized regions after each chemical step of modifying glass surfaces was taken to be a measure of the surface chemical heterogeneity. The attachment of γ-glycidoxypropyltrimethoxy silane (GPS) to glass decreased the pull-off forces relative to the clean glass and made the surface more uniform. The subsequent hydrolysis of the terminal epoxide groups resulted in a larger surface heterogeneity which was modeled by two populations of the terminal hydroxyl groups, each with its own distribution of adhesion forces and force variance. The activation of the hydroxyls with carbonyldiimmidazole (CDI) healed the surface and lowered its adhesion, however, the force variance remained rather large. Finally, the grafting of the α,ω-diamino poly(ethyleneoxide) chains to the CDI-activated glass largely eliminated adhesion except at a few discrete regions. The adhesion on the PEO grafted layer followed the Poisson distribution of the pull-off forces. With the exception of the glass surface, a correlation between the water contact angles and the mean pull-off forces measured with the Si(3)N(4) tip surfaces was found for all modified glass surfaces.

  9. Effect of Lamina Thickness of Prepreg on the Surface Accuracy of Carbon Fiber Composite Space Mirrors

    Science.gov (United States)

    Yang, Zhiyong; Tang, Zhanwen; Xie, Yongjie; Shi, Hanqiao; Zhang, Boming; Guo, Hongjun

    2018-02-01

    Composite space mirror can completely replicate the high-precision surface of mould by replication process, but the actual surface accuracy of the replication composite mirror always decreases. Lamina thickness of prepreg affects the layers and layup sequence of composite space mirror, and which would affect surface accuracy of space mirror. In our research, two groups of contrasting cases through finite element analyses (FEA) and comparative experiments were studied; the effect of different lamina thicknesses of prepreg and corresponding lay-up sequences was focused as well. We describe a special analysis model, validated process and result analysis. The simulated and measured surface figures both get the same conclusion. Reducing lamina thickness of prepreg used in replicating composite space mirror is propitious to optimal design of layup sequence for fabricating composite mirror, and could improve its surface accuracy.

  10. Influence of polishing on surface roughness following toothbrushing wear of composite resins.

    Science.gov (United States)

    Dalla-Vecchia, Karine Battestin; Taborda, Talita Damas; Stona, Deborah; Pressi, Heloísa; Burnett Júnior, Luiz Henrique; Rodrigues-Junior, Sinval Adalberto

    2017-01-01

    This study aimed to evaluate the influence of different polishing systems on the surface roughness of composite resins following procedures to simulate the effects of toothbrushing over time. Four currently available commercial composites were used to make 128 cylindrical specimens. The specimens were randomly allocated to polishing with a 1-step polisher or 1 of 3 multistep polishers (n = 8 per group). The baseline surface roughness was measured, and the specimens were submitted to 5000, 10,000, and 20,000 brushing cycles to represent toothbrushing throughout 6, 12, and 24 months, respectively. Results showed that surface roughness was influenced by the type of composite and polishing system and was not influenced by the simulated toothbrushing time. However, the surface roughness, as challenged by toothbrushing wear, was affected by the interaction among the composite, the polisher, and the toothbrushing time. The 1-step polisher produced the highest surface roughness and influenced toothbrushing wear resistance of some composites.

  11. [Application Progress of Three-dimensional Laser Scanning Technology in Medical Surface Mapping].

    Science.gov (United States)

    Zhang, Yonghong; Hou, He; Han, Yuchuan; Wang, Ning; Zhang, Ying; Zhu, Xianfeng; Wang, Mingshi

    2016-04-01

    The booming three-dimensional laser scanning technology can efficiently and effectively get spatial three-dimensional coordinates of the detected object surface and reconstruct the image at high speed,high precision and large capacity of information.Non-radiation,non-contact and the ability of visualization make it increasingly popular in three-dimensional surface medical mapping.This paper reviews the applications and developments of three-dimensional laser scanning technology in medical field,especially in stomatology,plastic surgery and orthopedics.Furthermore,the paper also discusses the application prospects in the future as well as the biomedical engineering problems it would encounter with.

  12. Surface mapping, organic matter and water stocks in peatlands of the Serra do Espinhaço meridional - Brazil

    Directory of Open Access Journals (Sweden)

    Márcio Luiz da Silva

    2013-10-01

    Full Text Available Peatlands are soil environments that store carbon and large amounts of water, due to their composition (90 % water, low hydraulic conductivity and a sponge-like behavior. It is estimated that peat bogs cover approximately 4.2 % of the Earth's surface and stock 28.4 % of the soil carbon of the planet. Approximately 612 000 ha of peatlands have been mapped in Brazil, but the peat bogs in the Serra do Espinhaço Meridional (SdEM were not included. The objective of this study was to map the peat bogs of the northern part of the SdEM and estimate the organic matter pools and water volume they stock. The peat bogs were pre-identified and mapped by GIS and remote sensing techniques, using ArcGIS 9.3, ENVI 4.5 and GPS Track Maker Pro software and the maps validated in the field. Six peat bogs were mapped in detail (1:20,000 and 1:5,000 by transects spaced 100 m and each transect were determined every 20 m, the UTM (Universal Transverse Mercator coordinates, depth and samples collected for characterization and determination of organic matter, according to the Brazilian System of Soil Classification. In the northern part of SdEM, 14,287.55 ha of peatlands were mapped, distributed over 1,180,109 ha, representing 1.2 % of the total area. These peatlands have an average volume of 170,021,845.00 m³ and stock 6,120,167 t (428.36 t ha-1 of organic matter and 142,138,262 m³ (9,948 m³ ha-1 of water. In the peat bogs of the Serra do Espinhaço Meridional, advanced stages of decomposing (sapric organic matter predominate, followed by the intermediate stage (hemic. The vertical growth rate of the peatlands ranged between 0.04 and 0.43 mm year-1, while the carbon accumulation rate varied between 6.59 and 37.66 g m-2 year-1. The peat bogs of the SdEM contain the headwaters of important water bodies in the basins of the Jequitinhonha and San Francisco Rivers and store large amounts of organic carbon and water, which is the reason why the protection and preservation

  13. Exercise body surface potential mapping in single and multiple coronary artery disease

    International Nuclear Information System (INIS)

    Montague, T.J.; Witkowski, F.X.; Miller, R.M.; Johnstone, D.E.; MacKenzie, R.B.; Spencer, C.A.; Horacek, B.M.

    1990-01-01

    Body surface ST integral maps were recorded in 36 coronary artery disease (CAD) patients at: rest; peak, angina-limited exercise; and, 1 and 5 min of recovery. They were compared to maps of 15 CAD patients who exercised to fatigue, without angina, and eight normal subjects. Peak exercise heart rates were similar (NS) in all groups. With exercise angina, patients with two and three vessel CAD had significantly (p less than 0.05) greater decrease in the body surface sum of ST integral values than patients with single vessel CAD. CAD patients with exercise fatigue, in the absence of angina, had decreased ST integrals similar (NS) to patients with single vessel CAD who manifested angina and the normal control subjects. There was, however, considerable overlap among individuals; some patients with single vessel CAD had as much exercise ST integral decrease as patients with three vessel CAD. All CAD patients had persistent ST integral decreases at 5 min of recovery and there was a direct correlation of the recovery and peak exercise ST changes. Exercise ST changes correlated, as well, with quantitative CAD angiographic scores, but not with thallium perfusion scores. These data suggest exercise ST integral body surface mapping allows quantitation of myocardium at ischemic risk in patients with CAD, irrespective of the presence or absence of ischemic symptoms during exercise. A major potential application of this technique is selection of CAD therapy guided by quantitative assessment of ischemic myocardial risk

  14. Whole brain diffeomorphic metric mapping via integration of sulcal and gyral curves, cortical surfaces, and images

    Science.gov (United States)

    Du, Jia; Younes, Laurent; Qiu, Anqi

    2011-01-01

    This paper introduces a novel large deformation diffeomorphic metric mapping algorithm for whole brain registration where sulcal and gyral curves, cortical surfaces, and intensity images are simultaneously carried from one subject to another through a flow of diffeomorphisms. To the best of our knowledge, this is the first time that the diffeomorphic metric from one brain to another is derived in a shape space of intensity images and point sets (such as curves and surfaces) in a unified manner. We describe the Euler–Lagrange equation associated with this algorithm with respect to momentum, a linear transformation of the velocity vector field of the diffeomorphic flow. The numerical implementation for solving this variational problem, which involves large-scale kernel convolution in an irregular grid, is made feasible by introducing a class of computationally friendly kernels. We apply this algorithm to align magnetic resonance brain data. Our whole brain mapping results show that our algorithm outperforms the image-based LDDMM algorithm in terms of the mapping accuracy of gyral/sulcal curves, sulcal regions, and cortical and subcortical segmentation. Moreover, our algorithm provides better whole brain alignment than combined volumetric and surface registration (Postelnicu et al., 2009) and hierarchical attribute matching mechanism for elastic registration (HAMMER) (Shen and Davatzikos, 2002) in terms of cortical and subcortical volume segmentation. PMID:21281722

  15. Modelling and analysis of flux surface mapping experiments on W7-X

    Science.gov (United States)

    Lazerson, Samuel; Otte, Matthias; Bozhenkov, Sergey; Sunn Pedersen, Thomas; Bräuer, Torsten; Gates, David; Neilson, Hutch; W7-X Team

    2015-11-01

    The measurement and compensation of error fields in W7-X will be key to the device achieving high beta steady state operations. Flux surface mapping utilizes the vacuum magnetic flux surfaces, a feature unique to stellarators and heliotrons, to allow direct measurement of magnetic topology, and thereby allows a highly accurate determination of remnant magnetic field errors. As will be reported separately at this meeting, the first measurements confirming the existence of nested flux surfaces in W7-X have been made. In this presentation, a synthetic diagnostic for the flux surface mapping diagnostic is presented. It utilizes Poincaré traces to construct an image of the flux surface consistent with the measured camera geometry, fluorescent rod sweep plane, and emitter beam position. Forward modeling of the high-iota configuration will be presented demonstrating an ability to measure the intrinsic error field using the U.S. supplied trim coil system on W7-X, and a first experimental assessment of error fields in W7-X will be presented. This work has been authored by Princeton University under Contract Number DE-AC02-09CH11466 with the US Department of Energy.

  16. Real-space Mapping of Surface Trap States in CIGSe Nanocrystals using 4D Electron Microscopy

    KAUST Repository

    Bose, Riya

    2016-05-26

    Surface trap states in semiconductor copper indium gallium selenide nanocrystals (NCs) which serve as undesirable channels for non-radiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with sub-picosecond temporal and nanometer spatial resolutions. Here, we precisely map the surface charge carrier dynamics of copper indium gallium selenide NCs before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs.

  17. Real-space Mapping of Surface Trap States in CIGSe Nanocrystals using 4D Electron Microscopy

    KAUST Repository

    Bose, Riya; Bera, Ashok; Parida, Manas R.; Adhikari, Aniruddha; Shaheen, Basamat; Alarousu, Erkki; Sun, Jingya; Wu, Tao; Bakr, Osman; Mohammed, Omar F.

    2016-01-01

    Surface trap states in semiconductor copper indium gallium selenide nanocrystals (NCs) which serve as undesirable channels for non-radiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with sub-picosecond temporal and nanometer spatial resolutions. Here, we precisely map the surface charge carrier dynamics of copper indium gallium selenide NCs before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs.

  18. Map of natural gamma radiation in Spain: radiometric characterization of different types of surfaces

    International Nuclear Information System (INIS)

    Suarez Mahou, E.; Fernandez Amigot, J.A.; Botas Medina, J.

    1997-01-01

    The gamma radioactivity flowing from ground and rocks is due to the presence in these of uranium, thorium and potassium-40. The method of radiometric characterization depends on the purpose of the undertaking. Radiometric characterization can be realized on big surfaces (tens or hundreds of square kilometres studied on a national scale), medium size surfaces (50 to 1000 square kilometres, for example, in epidemiological or biological studies in areas with a determined radiometric background) small surfaces of less than 50 square kilometres (industrial sites, pre-operational studies, etc.). This article considers aspects of radiometric characterization on surfaces of interest and describes the contribution of the MARNA (Natural Provisional Radiation Map of Spain) Project selection and radiometric characterization

  19. A comparative effect of various surface chemical treatments on the resin composite-composite repair bond strength

    Directory of Open Access Journals (Sweden)

    Shaloo Gupta

    2015-01-01

    Full Text Available Aim: The aim of this in vitro study was an attempt to investigate the effect of different surface treatments on the bond strength between pre-existing composite and repair composite resin. Materials and Methods: Forty acrylic blocks were prepared in a cuboidal mould. In each block, a well of 5 mm diameter and 5 mm depth was prepared to retain the composite resin (Filtek™ Z350, 3M/ESPE. Aging of the composite discs was achieved by storing them in water at 37°C for 1 week, and after that were divided into 5 groups (n = 8 according to surface treatment: Group I- 37% phosphoric acid, Group II-10% hydrofluoric acid, Group III-30% citric acid, Group IV-7% maleic acid and Group V- Adhesive (no etchant. The etched surfaces were rinsed and dried followed by application of bonding agent (Adper™ Single Bond 2. 3M/ESPE. The repair composite was placed on aged composite, light-cured for 40 seconds and stored in water at 37°C for 1 week. Shear bond strength between the aged and the new composite resin was determined with a universal testing machine (crosshead speed of 0.5 mm/min. Statistical Analysis: The compressive shear strengths were compared for differences using ANOVA test followed by Tamhane′s T2 post hoc analysis. Results: The surface treatment with 10% hydrofluoric acid showed the maximum bond strength followed by 30% citric acid, 7% maleic acid and 37% phosphoric acid in decreasing order. Conclusion: The use of 10% hydrofluoric acid can be a good alternative for surface treatment in repair of composite resin restoration as compared to commonly used 37% orthophosphoric acid.

  20. Crack path and fracture surface modifications in cement composites

    Directory of Open Access Journals (Sweden)

    Sajjad Ahmad

    2015-10-01

    Full Text Available There is a tremendous increase in the use of high strength and high performance self-consolidating cementitious composites due to their superior workability and mechanical strengths. Cement composites are quasi-brittle in nature and possess extremely low tensile strength as compared to their compressive strength. Due to the low tensile strength capacity, cracks develop in cementitious composites due to the drying shrinkage, plastic settlements and/or stress concentrations (due to external restrains and/or applied stresses etc. These cracks developed at the nanoscale may grow rapidly due to the applied stresses and join together to form micro and macro cracks. The growth of cracks from nanoscale to micro and macro scale is very rapid and may lead to sudden failure of the cement composites. The present paper reports the modifications in the crack growth pattern of the high performance cement composites to achieve enhanced ductility and toughness. The objective was accomplished by the incorporation of the micro sized inert particulates in the cement composite matrix. The results indicate that the incorporation of micro sized inert particles acted as the obstacles in the growth of the cracks thus improving the ductility and the energy absorption capacity of the self-consolidating cementitious composites.

  1. Methodology to design a municipal solid waste generation and composition map: A case study

    International Nuclear Information System (INIS)

    Gallardo, A.; Carlos, M.; Peris, M.; Colomer, F.J.

    2014-01-01

    Highlights: • To draw a waste generation and composition map of a town a lot of factors must be taken into account. • The methodology proposed offers two different depending on the available data combined with geographical information systems. • The methodology has been applied to a Spanish city with success. • The methodology will be a useful tool to organize the municipal solid waste management. - Abstract: The municipal solid waste (MSW) management is an important task that local governments as well as private companies must take into account to protect human health, the environment and to preserve natural resources. To design an adequate MSW management plan the first step consist in defining the waste generation and composition patterns of the town. As these patterns depend on several socio-economic factors it is advisable to organize them previously. Moreover, the waste generation and composition patterns may vary around the town and over the time. Generally, the data are not homogeneous around the city as the number of inhabitants is not constant nor it is the economic activity. Therefore, if all the information is showed in thematic maps, the final waste management decisions can be made more efficiently. The main aim of this paper is to present a structured methodology that allows local authorities or private companies who deal with MSW to design its own MSW management plan depending on the available data. According to these data, this paper proposes two ways of action: a direct way when detailed data are available and an indirect way when there is a lack of data and it is necessary to take into account bibliographic data. In any case, the amount of information needed is considerable. This paper combines the planning methodology with the Geographic Information Systems to present the final results in thematic maps that make easier to interpret them. The proposed methodology is a previous useful tool to organize the MSW collection routes including the

  2. Shear-bond-strength of orthodontic brackets to aged nano-hybrid composite-resin surfaces using different surface preparation.

    Science.gov (United States)

    Demirtas, Hatice Kubra; Akin, Mehmet; Ileri, Zehra; Basciftci, Faruk Ayhan

    2015-01-01

    The aim of this study was to evaluate the effects of different surface preparation methods on the shear bond strength (SBS) of orthodontic metal brackets to aged nano-hybrid resin composite surfaces in vitro. A total of 100 restorative composite resin discs, 6 mm in diameter and 3 mm thick, were obtained and treated with an ageing procedure. After ageing, the samples were randomly divided as follows according to surface preparation methods: (1)Control, (2)37% phosphoric acid gel, (3)Sandblasting, (4)Diamond bur, (5)Air-flow and 20 central incisor teeth were used for the control etched group. SBS test were applied on bonded metal brackets to all samples. SBS values and residual adhesives were evaluated. Analysis of variance showed a significant difference (porthodontic metal brackets to nano-hybrid composite resin surfaces.

  3. Humidity Sensing Properties of Surface Modified Polyaniline Metal Oxide Composites

    Directory of Open Access Journals (Sweden)

    S. C. Nagaraju

    2014-01-01

    Full Text Available Polyaniline- (PANI praseodymium Oxide (Pr2O3 composites have been synthesized by in situ polymerization method with different weight percentages. The synthesized composites have been characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The temperature dependent conductivity shows that the conductivity is due to the hopping of polarons and bipolarons. These composites show negative thermal coefficient (α behavior as a function of temperature, which is characteristic behavior of semiconducting materials. Sensor studies have been carried out by two-probe method and found that the sensitivity increases with increase in % RH. It is noticed that stability increase is due to the presence of Pr2O3 in polyaniline up to 30 wt%. A fast recovery and response time along with high sensitivity make these composites suitable for humidity sensors.

  4. Hyperspectral surface materials map of quadrangle 3564, Jowand (405) and Gurziwan (406) quadrangles, Afghanistan, showing carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    Science.gov (United States)

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. The map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Epidote or chlorite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  5. Hyperspectral surface materials map of quadrangle 3264, Naw Zad-Musa Qala (423) and Dihrawud (424) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  6. Hyperspectral surface materials map of quadrangle 3266, Uruzgan (519) and Moqur (520) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  7. Hyperspectral surface materials map of quadrangle 3464, Shahrak (411) and Kasi (412) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  8. Hyperspectral surface materials map of quadrangle 3466, La`l wa Sar Jangal (507) and Bamyan (508) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  9. Hyperspectral surface materials map of quadrangle 3260, Dasht-e-Chah-e-Mazar (419) and Anar Darah (420) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  10. Hyperspectral surface materials map of quadrangle 3470, Jalalabad (511) and Chaghasaray (512) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  11. Hyperspectral surface materials map of quadrangle 3570, Tagab-e-Munjan (505) and Asmar-Kamdesh (506) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  12. Hyperspectral surface materials map of quadrangle 3364, Pasaband (417) and Markaz-e Kajiran (418) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  13. Hyperspectral surface materials map of quadrangle 3462, Herat (409) and Chishti Sharif (410) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  14. Hyperspectral surface materials map of quadrangle 3468, Chak-e Wardak-Siyahgird (509) and Kabul (510) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  15. Hyperspectral surface materials map of quadrangle 3368, Ghazni (515) and Gardez (516) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  16. Hyperspectral surface materials map of quadrangle 3162, Chakhansur (603) and Kotalak (604) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  17. Hyperspectral surface materials map of quadrangle 3362, Shindand (415) and Tulak (416) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  18. Hyperspectral surface materials map of quadrangle 3366, Gizab (513) and Nawer (514) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  19. Hyperspectral surface materials map of quadrangle 3770, Faizabad (217) and Parkhaw (218) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  20. Hyperspectral surface materials map of quadrangle 3564, Jowand (405) and Gurziwan (406) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  1. Hyperspectral surface materials map of quadrangle 3166, Jaldak (701) and Maruf-Nawa (702) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  2. Hyperspectral surface materials map of quadrangle 3566, Sangcharak (501) and Sayghan-o-Kamard (502) quadrangles, Afghanistan, showing iron-bearing minerals and other material

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  3. Hyperspectral surface materials map of quadrangle 3670, Jurm-Kishim (223) and Zebak (224) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  4. Hyperspectral surface materials map of quadrangle 3568, Pul-e Khumri (503) and Charikar (504) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  5. Hyperspectral surface materials map of quadrangle 3262, Farah (421) and Hokumat-e-pur-Chaman (422) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  6. Hyperspectral surface materials map of quadrangle 3164, Lashkar Gah (605) and Kandahar (606) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  7. Hyperspectral surface materials map of quadrangle 3562, Khawja-Jir (403) and Murghab (404) quadrangles, Afghanistan, showing iron-bearing minerals and other materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Johnson, Michaela R.; Giles, Stuart A.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  8. Hyperspectral Surface Materials Map of Quadrangle 3268, Khayr Kot (521) and Urgun (522) Quadrangles, Afghanistan, Showing Iron-bearing Minerals and Other Materials

    Science.gov (United States)

    King, Trude V.V.; Hoefen, Todd M.; Kokaly, Raymond F.; Livo, Keith E.; Giles, Stuart A.; Johnson, Michaela R.

    2013-01-01

    This map shows the spatial distribution of selected iron-bearing minerals and other materials derived from analysis of airborne HyMap™ imaging spectrometer (hyperspectral) data of Afghanistan collected in late 2007. This map is one in a series of U.S. Geological Survey/Afghanistan Geological Survey quadrangle maps covering Afghanistan. Flown at an altitude of 50,000 feet (15,240 meters (m)), the HyMap™ imaging spectrometer measured reflected sunlight in 128 channels, covering wavelengths between 0.4 and 2.5 μm. The data were georeferenced, atmospherically corrected and converted to apparent surface reflectance, empirically adjusted using ground-based reflectance measurements, and combined into a mosaic with 23-m pixel spacing. Variations in water vapor and dust content of the atmosphere, in solar angle, and in surface elevation complicated correction; therefore, some classification differences may be present between adjacent flight lines. The reflectance spectrum of each pixel of HyMap™ imaging spectrometer data was compared to the reference materials in a spectral library of minerals, vegetation, water, and other materials. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated, while minerals having slightly different compositions but similar spectral features were less easily discriminated; thus, some map classes consist of several minerals having similar spectra, such as “Goethite and jarosite.” A designation of “Not classified” was assigned to the pixel when there was no match with reference spectra.

  9. [Effect of thermal cycling on surface microstructure of different light-curing composite resins].

    Science.gov (United States)

    Lv, Da; Liu, Kai-Lei; Yao, Yao; Zhang, Wei-Sheng; Liao, Chu-Hong; Jiang, Hong

    2015-04-01

    To evaluate the effect of thermal cycling on surface microstructure of different light-curing composite resins. A nanofilled composite (Z350) and 4 microhybrid composites (P60, Z250, Spectrum, and AP-X) were fabricated from lateral to center to form cubic specimens. The lateral surfaces were abrased and polished before water storage and 40 000 thermal cycles (5/55 degrees celsius;). The mean surface roughness (Ra) were measured and compared before and after thermal cycling, and the changes of microstructure were observed under scanning electron microscope (SEM). Significant decreases of Ra were observed in the composites, especially in Spectrum (from 0.164±0.024 µm to 0.140±0.017 µm, Presins, and fissures occurred on Z350 following the thermal cycling. Water storage and thermal cycling may produce polishing effect on composite resins and cause fissures on nanofilled composite resins.

  10. Surface roughness comparison of methacrylate and silorane-based composite resins after 40% hydrogen peroxide application

    Directory of Open Access Journals (Sweden)

    Rori Sasmita

    2018-01-01

    Full Text Available The change of the tooth colour could be restored with bleaching. The tooth bleaching will affects the surface roughness of the composite resins. Recently, the material basis for composite resins has developed, among others are methacrylate-based and silorane based composite resins. The objective of this study was to distinguish the surface roughness value of methacrylate-based composite resin and silorane based composite resins. This research was quasi-experimental. The sample used in this study were methacrylate and silorane based composite resins in discs form, with the size of 6 mm and the thickness of 3 mm, manufactured into 20 specimens and divided into 2 groups. The control group was immersed in the artificial saliva, and the treatment group was applied with 40% hydrogen peroxide. The result of the experiment analyzed using unpaired sample t-test showed significant differences in the average value of the surface roughness after the application of 40% hydrogen peroxide. The average value of methacrylate and silorane based composite resins were 2.744 μm and 3.417 μm, respectively. There was a difference in the surface roughness of methacrylate and silorane based composite resin compounds after the application of 40% hydrogen peroxide. The surface roughness value of the silorane-based composite resin was higher than the methacrylate-based.

  11. Comparison Effectiveness of Pixel Based Classification and Object Based Classification Using High Resolution Image In Floristic Composition Mapping (Study Case: Gunung Tidar Magelang City)

    Science.gov (United States)

    Ardha Aryaguna, Prama; Danoedoro, Projo

    2016-11-01

    Developments of analysis remote sensing have same way with development of technology especially in sensor and plane. Now, a lot of image have high spatial and radiometric resolution, that's why a lot information. Vegetation object analysis such floristic composition got a lot advantage of that development. Floristic composition can be interpreted using a lot of method such pixel based classification and object based classification. The problems for pixel based method on high spatial resolution image are salt and paper who appear in result of classification. The purpose of this research are compare effectiveness between pixel based classification and object based classification for composition vegetation mapping on high resolution image Worldview-2. The results show that pixel based classification using majority 5×5 kernel windows give the highest accuracy between another classifications. The highest accuracy is 73.32% from image Worldview-2 are being radiometric corrected level surface reflectance, but for overall accuracy in every class, object based are the best between another methods. Reviewed from effectiveness aspect, pixel based are more effective then object based for vegetation composition mapping in Tidar forest.

  12. Accuracy Analysis of a Robotic Radionuclide Inspection and Mapping System for Surface Contamination

    International Nuclear Information System (INIS)

    Mauer, Georg F.; Kawa, Chris

    2008-01-01

    The mapping of localized regions of radionuclide contamination in a building can be a time consuming and costly task. Humans moving hand-held radiation detectors over the target areas are subject to fatigue. A contamination map based on manual surveys can contain significant operator-induced inaccuracies. A Fanuc M16i light industrial robot has been configured for installation on a mobile aerial work platform, such as a tall forklift. When positioned in front of a wall or floor surface, the robot can map the radiation levels over a surface area of up to 3 m by 3 m. The robot's end effector is a commercial alpha-beta radiation sensor, augmented with range and collision avoidance sensors to ensure operational safety as well as to maintain a constant gap between surface and radiation sensors. The accuracy and repeatability of the robotically conducted contamination surveys is directly influenced by the sensors and other hardware employed. This paper presents an in-depth analysis of various non-contact sensors for gap measurement, and the means to compensate for predicted systematic errors that arise during the area survey scans. The range sensor should maintain a constant gap between the radiation counter and the surface being inspected. The inspection robot scans the wall surface horizontally, moving down at predefined vertical intervals after each scan in a meandering pattern. A number of non-contact range sensors can be employed for the measurement of the gap between the robot end effector and the wall. The nominal gap width was specified as 10 mm, with variations during a single scan not to exceed ± 2 mm. Unfinished masonry or concrete walls typically exhibit irregularities, such as holes, gaps, or indentations in mortar joints. These irregularities can be sufficiently large to indicate a change of the wall contour. The responses of different sensor types to the wall irregularities vary, depending on their underlying principles of operation. We explored

  13. Mapping Forest Species Composition Using Imaging Spectrometry and Airborne Laser Scanner Data

    Science.gov (United States)

    Torabzadeh, H.; Morsdorf, F.; Leiterer, R.; Schaepman, M. E.

    2013-09-01

    Accurate mapping of forest species composition is an important aspect of monitoring and management planning related to ecosystem functions and services associated with water refinement, carbon sequestration, biodiversity, and wildlife habitats. Although different vegetation species often have unique spectral signatures, mapping based on spectral reflectance properties alone is often an ill-posed problem, since the spectral signature is as well influenced by age, canopy gaps, shadows and background characteristics. Thus, reducing the unknown variation by knowing the structural parameters of different species should improve determination procedures. In this study we combine imaging spectrometry (IS) and airborne laser scanning (ALS) data of a mixed needle and broadleaf forest to differentiate tree species more accurately as single-instrument data could do. Since forest inventory data in dense forests involve uncertainties, we tried to refine them by using individual tree crowns (ITC) position and shape, which derived from ALS data. Comparison of the extracted spectra from original field data and the modified one shows how ALS-derived shape and position of ITCs can improve separablity of the different species. The spatially explicit information layers containing both the spectral and structural components from the IS and ALS datasets were then combined by using a non-parametric support vector machine (SVM) classifier.

  14. Thermal performance enhancement of erythritol/carbon foam composites via surface modification of carbon foam

    Science.gov (United States)

    Li, Junfeng; Lu, Wu; Luo, Zhengping; Zeng, Yibing

    2017-03-01

    The thermal performance of the erythritol/carbon foam composites, including thermal diffusivity, thermal capacity, thermal conductivity and latent heat, were investigated via surface modification of carbon foam using hydrogen peroxide as oxider. It was found that the surface modification enhanced the wetting ability of carbon foam surface to the liquid erythritol of the carbon foam surface and promoted the increase of erythritol content in the erythritol/carbon foam composites. The dense interfaces were formed between erythritol and carbon foam, which is due to that the formation of oxygen functional groups C=O and C-OH on the carbon surface increased the surface polarity and reduced the interface resistance of carbon foam surface to the liquid erythritol. The latent heat of the erythritol/carbon foam composites increased from 202.0 to 217.2 J/g through surface modification of carbon foam. The thermal conductivity of the erythritol/carbon foam composite before and after surface modification further increased from 40.35 to 51.05 W/(m·K). The supercooling degree of erythritol also had a large decrease from 97 to 54 °C. Additionally, the simple and effective surface modification method of carbon foam provided an extendable way to enhance the thermal performances of the composites composed of carbon foams and PCMs.

  15. A wafer mapping technique for residual stress in surface micromachined films

    International Nuclear Information System (INIS)

    Schiavone, G; Murray, J; Smith, S; Walton, A J; Desmulliez, M P Y; Mount, A R

    2016-01-01

    The design of MEMS devices employing movable structures is crucially dependant on the mechanical behaviour of the deposited materials. It is therefore important to be able to fully characterize the micromachined films and predict with confidence the mechanical properties of patterned structures. This paper presents a characterization technique that enables the residual stress in MEMS films to be mapped at the wafer level by using microstructures released by surface micromachining. These dedicated MEMS test structures and the associated measurement techniques are used to extract localized information on the strain and Young’s modulus of the film under investigation. The residual stress is then determined by numerically coupling this data with a finite element analysis of the structure. This paper illustrates the measurement routine and demonstrates it with a case study using electrochemically deposited alloys of nickel and iron, particularly prone to develop high levels of residual stress. The results show that the technique enables wafer mapping of film non-uniformities and identifies wafer-to-wafer differences. A comparison between the results obtained from the mapping technique and conventional wafer bow measurements highlights the benefits of using a procedure tailored to films that are non-uniform, patterned and surface-micromachined, as opposed to simple standard stress extraction methods. The presented technique reveals detailed information that is generally unexplored when using conventional stress extraction methods such as wafer bow measurements. (paper)

  16. The multifractal structure of satellite sea surface temperature maps can be used to obtain global maps of streamlines

    Directory of Open Access Journals (Sweden)

    A. Turiel

    2009-10-01

    Full Text Available Nowadays Earth observation satellites provide information about many relevant variables of the ocean-climate system, such as temperature, moisture, aerosols, etc. However, to retrieve the velocity field, which is the most relevant dynamical variable, is still a technological challenge, specially in the case of oceans. New processing techniques, emerged from the theory of turbulent flows, have come to assist us in this task. In this paper, we show that multifractal techniques applied to new Sea Surface Temperature satellite products opens the way to build maps of ocean currents with unprecedented accuracy. With the application of singularity analysis, we show that global ocean circulation patterns can be retrieved in a daily basis. We compare these results with high-quality altimetry-derived geostrophic velocities, finding a quite good correspondence of the observed patterns both qualitatively and quantitatively; and this is done for the first time on a global basis, even for less active areas. The implications of this findings from the perspective both of theory and of operational applications are discussed.

  17. [Studies of marker screening efficiency and corresponding influencing factors in QTL composite interval mapping].

    Science.gov (United States)

    Gao, Yong-Ming; Wan, Ping

    2002-06-01

    Screening markers efficiently is the foundation of mapping QTLs by composite interval mapping. Main and interaction markers distinguished, besides using background control for genetic variation, could also be used to construct intervals of two-way searching for mapping QTLs with epistasis, which can save a lot of calculation time. Therefore, the efficiency of marker screening would affect power and precision of QTL mapping. A doubled haploid population with 200 individuals and 5 chromosomes was constructed, with 50 markers evenly distributed at 10 cM space. Among a total of 6 QTLs, one was placed on chromosome I, two linked on chromosome II, and the other three linked on chromosome IV. QTL setting included additive effects and epistatic effects of additive x additive, the corresponding QTL interaction effects were set if data were collected under multiple environments. The heritability was assumed to be 0.5 if no special declaration. The power of marker screening by stepwise regression, forward regression, and three methods for random effect prediction, e.g. best linear unbiased prediction (BLUP), linear unbiased prediction (LUP) and adjusted unbiased prediction (AUP), was studied and compared through 100 Monte Carlo simulations. The results indicated that the marker screening power by stepwise regression at 0.1, 0.05 and 0.01 significant level changed from 2% to 68%, the power changed from 2% to 72% by forward regression. The larger the QTL effects, the higher the marker screening power. While the power of marker screening by three random effect prediction was very low, the maximum was only 13%. That suggested that regression methods were much better than those by using the approaches of random effect prediction to identify efficient markers flanking QTLs, and forward selection method was more simple and efficient. The results of simulation study on heritability showed that heightening of both general heritability and interaction heritability of genotype x

  18. Quantitative morphological and compositional evaluation of laboratory prepared aluminoborosilicate glass surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yuxuan, E-mail: yg4@alfred.edu; Wren, Anthony W.; Mellott, Nathan P.

    2015-01-01

    Graphical abstract: - Highlights: • Aluminoborosilicate glass surfaces were prepared through both melting and polishing/etching and the surface composition and morphology were quantified as a function of processing method. • Glass surface morphology was quantified using PSD analysis, followed by both fractal and ABC model fitting, resulting in a comprehensive description of the spatial distribution of roughness. • All melt surfaces showed a depletion in Na, Ca, and B with respect to the bulk composition. Polished/etched surfaces showed a depletion in Na, B, and Al with respect to the bulk composition. • It was found that increasing heat treatment temperature of melt surfaces lead to a decrease in equivalent roughness and an increased spatial homogeneity of roughness while etching of polished ISG glass surfaces decreases the roughness and spatial distribution homogeneity of roughness. - Abstract: Surface finishing techniques including polishing, etching and heat treatment can modify the topography and the surface chemical composition of glasses. It is widely acknowledged that atomic force microscopy (AFM) can be used to quantify the morphology of surfaces, providing various parameters including average, peak-to-valley, and apparent root-mean-square roughness. Furthermore advanced power spectral density (PSD) analysis of AFM-derived surface profiles offers quantification of the spatial homogeneity of roughness values along different wavelengths, resulting in parameters including equivalent RMS, Hurst exponent, and fractal dimension. Outermost surface (∼8 nm) chemical composition can be quantitatively measured by X-ray photoelectron spectroscopy. In this paper, we first developed a series of surface finishing methods for an aluminoborosilicate glass system by polishing, etching or heat treatment. The chemical composition and environment of prepared glass surfaces were quantified by XPS and topographical analysis was carried out by fractal and k

  19. Retrieval Algorithms for Road Surface Modelling Using Laser-Based Mobile Mapping

    Directory of Open Access Journals (Sweden)

    Antero Kukko

    2008-09-01

    Full Text Available Automated processing of the data provided by a laser-based mobile mapping system will be a necessity due to the huge amount of data produced. In the future, vehiclebased laser scanning, here called mobile mapping, should see considerable use for road environment modelling. Since the geometry of the scanning and point density is different from airborne laser scanning, new algorithms are needed for information extraction. In this paper, we propose automatic methods for classifying the road marking and kerbstone points and modelling the road surface as a triangulated irregular network. On the basis of experimental tests, the mean classification accuracies obtained using automatic method for lines, zebra crossings and kerbstones were 80.6%, 92.3% and 79.7%, respectively.

  20. Mapping chemical elements on the surface of orthodontic appliance by SEM-EDX.

    Science.gov (United States)

    Mikulewicz, Marcin; Wołowiec, Paulina; Michalak, Izabela; Chojnacka, Katarzyna; Czopor, Wojciech; Berniczei-Royko, Adam; Vegh, Andras; Gedrange, Thomas

    2014-05-25

    During orthodontic treatment, the various elements that constitute the fixed appliance undergo different processes. As a result of a change of the surface, elution/coverage of metals on the surface can be observed in the process of corrosion/passivation. Scanning electron microscopy with an energy-dispersive X-ray analytical system (SEM-EDX) was used to analyze the composition of stainless steel elements of orthodontic fixed appliances (before and after orthodontic treatment), to obtain the composition of the surface of the elements. The analyzed elements were: brackets (Victory Series APC PLUS 022, 3M Unitek, Monrovia, CA, USA); wires (0.017×0.025, 3M Unitek, Monrovia, CA, USA); and bands (37+, 3M Unitek, Monrovia, CA, USA). The results showed a decrease of chromium and iron contribution to the surface, with increase of oxygen content in used vs. new elements of the appliance. Our results confirm the formation of oxides (passivation layer) on the surface of stainless steel as a result of the presence of the orthodontic appliance in patients' oral cavities.

  1. Effects of 35% Carbamide Peroxide Gel on Surface Roughness and Hardness of Composite Resins

    Directory of Open Access Journals (Sweden)

    F. Sharafeddin

    2010-03-01

    Full Text Available Objective: Bleaching agents may not be safe for dental materials. The purpose of this invitro study was to evaluate the effects of Opalescent Quick "in-office bleaching gel" containing 35% carbamide peroxide on the surface roughness and hardness of microfilled(Heliomolar and hybride (Spectrum TPH composite resins.Materials and Methods: Twenty specimens of Spectrum TPH composite resins and twenty Heliomolar composite resins were fabricated using a metallic ring (6.5 mm diameter and 2.5 mm thickness and light cured, then their surfaces were polished. Specimens of each composite resin were divided into two equal groups. Ten specimens of each type of composite were stored in water at 37°C as the control groups and 35% carbamide peroxide gel (Opalescence Quick as the other group for 30 minutes a week for 3 weeks. Then the specimens were subject to roughness and hardness tests.Results: This study revealed that using 35% carbamide peroxide bleaching gels had no significant effect on the surface roughness of Spectrum TPH "hybrid" and Heliomolar "microfilled" composite resins. The surface hardness of Spectrum TPH composite treated with the subject gel significantly increased compared to heliomolar, which had no significant change after treatment with this bleaching gel.Conclusion: If tooth color matching of the composite had been satisfactory after office bleaching with 35% carbamide peroxide gel, this material would have been acceptable because it has no adverse effect on Heliomolar and Spectrum TPH composite resins.

  2. Three-dimensional modeling of chloroprene rubber surface topography upon composition

    Energy Technology Data Exchange (ETDEWEB)

    Žukienė, Kristina, E-mail: kristina.zukiene@ktu.lt [Department of Clothing and Polymer Products Technology, Kaunas University of Technology, Studentu St. 56, LT-51424 Kaunas (Lithuania); Jankauskaitė, Virginija [Department of Clothing and Polymer Products Technology, Kaunas University of Technology, Studentu St. 56, LT-51424 Kaunas (Lithuania); Petraitienė, Stase [Department of Applied Mathematics, Kaunas University of Technology, Studentu 50, LT-51368 Kaunas (Lithuania)

    2014-02-15

    In this study the effect of polymer blend composition on the surface roughness has been investigated and simulated. Three-dimensional modeling of chloroprene rubber film surface upon piperylene-styrene copolymer content was conducted. The efficiency of various surface roughness modeling methods, including Monte Carlo, surface growth and proposed method, named as parabolas, were compared. The required parameters for modeling were obtained from atomic force microscopy topographical images of polymer films surface. It was shown that experimental and modeled surfaces have the same correlation function. The quantitative comparison of function parameters was made. It was determined that novel parabolas method is suitable for three-dimensional polymer blends surface roughness description.

  3. Modified titanium surface with gelatin nano gold composite increases osteoblast cell biocompatibility

    International Nuclear Information System (INIS)

    Lee, Young-Hee; Bhattarai, Govinda; Aryal, Santosh; Lee, Nan-Hee; Lee, Min-Ho; Kim, Tae-Gun; Jhee, Eun-Chung; Kim, Hak-Yong; Yi, Ho-Keun

    2010-01-01

    This study examined the gelatin nano gold (GnG) composite for surface modification of titanium in addition to insure biocompatibility on dental implants or biomaterials. The GnG composite was constructed by gelatin and hydrogen tetrachloroaurate in presence of reducing agent, sodium borohydrate (NabH 4 ). The GnG composite was confirmed by UV-VIS spectroscopy and transmission electron microscopy (TEM). A dipping method was used to modify the titanium surface by GnG composite. Surface was characterized by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The MC-3T3 E1 cell viability was assessed by trypan blue and the expression of proteins to biocompatibility were analyzed by Western blotting. The GnG composite showed well dispersed character, the strong absorption at 530 nm, roughness, regular crystal and clear C, Na, Cl, P, and Au signals onto titanium. Further, this composite allowed MC-3T3 E1 growth and viability compared to gelatin and pure titanium. It induced ERK activation and the expression of cell adherent molecules, FAK and SPARC, and growth factor, VEGF. However, GnG decreased the level of SAPK/JNK. This shows that GnG composite coated titanium surfaces have a good biocompatibility for osteoblast growth and attachment than in intact by simple and versatile dipping method. Furthermore, it offers good communication between cell and implant surfaces by regulating cell signaling and adherent molecules, which are useful to enhance the biocompatibility of titanium surfaces.

  4. Effect of the surface roughness on interfacial properties of carbon fibers reinforced epoxy resin composites

    International Nuclear Information System (INIS)

    Song Wei; Gu Aijuan; Liang Guozheng; Yuan Li

    2011-01-01

    The effect of the surface roughness on interfacial properties of carbon fibers (CFs) reinforced epoxy (EP) resin composite is studied. Aqueous ammonia was applied to modify the surfaces of CFs. The morphologies and chemical compositions of original CFs and treated CFs (a-CFs) were characterized by Atomic Force Microscopy (AFM), and X-ray Photoelectron Spectroscopy (XPS). Compared with the smooth surface of original CF, the surface of a-CF has bigger roughness; moreover, the roughness increases with the increase of the treating time. On the other hand, no obvious change in chemical composition takes place, indicating that the treating mechanism of CFs by aqueous ammonia is to physically change the morphologies rather than chemical compositions. In order to investigate the effect of surface roughness on the interfacial properties of CF/EP composites, the wettability and Interfacial Shear Strength (IFSS) were measured. Results show that with the increase of the roughness, the wettabilities of CFs against both water and ethylene glycol improves; in addition, the IFSS value of composites also increases. These attractive phenomena prove that the surface roughness of CFs can effectively overcome the poor interfacial adhesions between CFs and organic matrix, and thus make it possible to fabricate advanced composites based on CFs.

  5. Influence of composition and roughness on the pigment mapping of paintings using mid-infrared fiberoptics reflectance spectroscopy (mid-IR FORS) and multivariate calibration.

    Science.gov (United States)

    Sessa, Clarimma; Bagán, Héctor; García, Jose Francisco

    2014-10-01

    Mid-infrared fiberoptics reflectance spectroscopy (mid-IR FORS) is a very interesting technique for artwork characterization purposes. However, the fact that the spectra obtained are a mixture of surface (specular) and volume (diffuse) reflection is a significant drawback. The physical and chemical features of the artwork surface may produce distortions in the spectra that hinder comparison with reference databases acquired in transmission mode. Several studies attempted to understand the influence of the different variables and propose procedures to improve the interpretation of the spectra. This article is focused on the application of mid-IR FORS and multivariate calibration to the analysis of easel paintings. The objectives are the evaluation of the influence of the surface roughness on the spectra, the influence of the matrix composition for the classification of unknown spectra, and the capability of obtaining pigment composition mappings. A first evaluation of a fast procedure for spectra management and pigment discrimination is discussed. The results demonstrate the capability of multivariate methods, principal component analysis (PCA), and partial least squares discrimination analysis (PLS-DA), to model the distortions of the reflectance spectra and to delimitate and discriminate areas of uniform composition. The roughness of the painting surface is found to be an important factor affecting the shape and relative intensity of the spectra. A mapping of the major pigments of a painting is possible using mid-IR FORS and PLS-DA when the calibration set is a palette that includes the potential pigments present in the artwork mixed with the appropriate binder and that shows the different paint textures.

  6. Digital map and situation surface: a team-oriented multidisplay workspace for network enabled situation analysis

    Science.gov (United States)

    Peinsipp-Byma, E.; Geisler, Jürgen; Bader, Thomas

    2009-05-01

    System concepts for network enabled image-based ISR (intelligence, surveillance, reconnaissance) is the major mission of Fraunhofer IITB's applied research in the area of defence and security solutions. For the TechDemo08 as part of the NATO CNAD POW Defence against terrorism Fraunhofer IITB advanced a new multi display concept to handle the shear amount and high complexity of ISR data acquired by networked, distributed surveillance systems with the objective to support the generation of a common situation picture. Amount and Complexity of ISR data demands an innovative man-machine interface concept for humans to deal with it. The IITB's concept is the Digital Map & Situation Surface. This concept offers to the user a coherent multi display environment combining a horizontal surface for the situation overview from the bird's eye view, an attached vertical display for collateral information and so-called foveatablets as personalized magic lenses in order to obtain high resolved and role-specific information about a focused areaof- interest and to interact with it. In the context of TechDemo08 the Digital Map & Situation Surface served as workspace for team-based situation visualization and analysis. Multiple sea- and landside surveillance components were connected to the system.

  7. Landing Site Selection and Surface Traverse Planning using the Lunar Mapping & Modeling Portal

    Science.gov (United States)

    Law, E.; Chang, G.; Bui, B.; Sadaqathullah, S.; Kim, R.; Dodge, K.; Malhotra, S.

    2013-12-01

    Introduction: The Lunar Mapping and Modeling Portal (LMMP), is a web-based Portal and a suite of interactive visualization and analysis tools for users to access mapped lunar data products (including image mosaics, digital elevation models, etc.) from past and current lunar missions (e.g., Lunar Reconnaissance Orbiter, Apollo, etc.), and to perform in-depth analyses to support lunar surface mission planning and system design for future lunar exploration and science missions. It has been widely used by many scientists mission planners, as well as educators and public outreach (e.g., Google Lunar XPRICE teams, RESOLVE project, museums etc.) This year, LMMP was used by the Lunar and Planetary Institute (LPI)'s Lunar Exploration internship program to perform lighting analysis and local hazard assessments, such as, slope, surface roughness and crater/boulder distribution to research landing sites and surface pathfinding and traversal. Our talk will include an overview of LMMP, a demonstration of the tools as well as a summary of the LPI Lunar Exploration summer interns' experience in using those tools.

  8. Comparison of time-dependent changes in the surface hardness of different composite resins

    Science.gov (United States)

    Ozcan, Suat; Yikilgan, Ihsan; Uctasli, Mine Betul; Bala, Oya; Kurklu, Zeliha Gonca Bek

    2013-01-01

    Objective: The aim of this study was to evaluate the change in surface hardness of silorane-based composite resin (Filtek Silorane) in time and compare the results with the surface hardness of two methacrylate-based resins (Filtek Supreme and Majesty Posterior). Materials and Methods: From each composite material, 18 wheel-shaped samples (5-mm diameter and 2-mm depth) were prepared. Top and bottom surface hardness of these samples was measured using a Vicker's hardness tester. The samples were then stored at 37°C and 100% humidity. After 24 h and 7, 30 and 90 days, the top and bottom surface hardness of the samples was measured. In each measurement, the rate between the hardness of the top and bottom surfaces were recorded as the hardness rate. Statistical analysis was performed by one-way analysis of variance, multiple comparisons by Tukey's test and binary comparisons by t-test with a significance level of P = 0.05. Results: The highest hardness values were obtained from each two surfaces of Majesty Posterior and the lowest from Filtek Silorane. Both the top and bottom surface hardness of the methacrylate based composite resins was high and there was a statistically significant difference between the top and bottom hardness values of only the silorane-based composite, Filtek Silorane (P composite resin Filtek Silorane showed adequate hardness ratio, the use of incremental technic during application is more important than methacrylate based composites. PMID:24966724

  9. Pluto and Charon: Surface Colors and Compositions - A Hypothesis

    Science.gov (United States)

    Cruikshank, D. P.

    2016-01-01

    The surface of Pluto displays an array of colors ranging from yellow to red to brown, while the surface of Charon is largely gray with a north polar zone of red color similar to regions on Pluto. Pluto's surface shows layers of intensely colored material in tilted and transported blocks, and fractured geo-graphical units. This arrangement suggests episodes of formation or deposition of that material interspersed with episodes of emplacement of ices having little or no color. The ices identified on the surfaces of these two bodies (N2, CH4, CO, C2H6, H2O on Pluto, and H2O and NH3 on Charon) are colorless, as are nearly all ices in a powdery state. The colors on Pluto probably arise from the in situ formation of a macro-molecular carbonaceous material generated by energetic processing of the ices on the surface. Laboratory experiments producing refractory tholins particularly relevant to Pluto explored the chemistry of both UV and low-energy electron bombardment of a mix of Pluto ices (N2:CH4:CO = 100:1:1). We can term this Pluto ice tholin PIT. Water ice in the crystalline state characterizes Charon's surface, and while most of Charon's surface is neutral in color, with geometric albedo approximately 0.38, the polar zone and a light cover of fainter but similar reddish color over some surface regions suggest a common origin with the colored material on Pluto. NH3 or NH3 x nH2O was identified from disk-integrated Earth-based spectra, and a few concentrated NH3 exposures have been found in the New Horizons spectral images.

  10. Effects of surface-mapping corrections and synthetic-aperture focusing techniques on ultrasonic imaging

    International Nuclear Information System (INIS)

    Barna, B.A.; Johnson, J.A.

    1981-01-01

    Improvements in ultrasonic imaging that can be obtained using algorithms that map the surface of targets are evaluated. This information is incorporated in the application of synthetic-aperture focusing techniques which also have the potential to improve image resolution. Images obtained using directed-beam (flat) transducers and the focused transducers normally used for synthetic-aperture processing are quantitatively compared by using no processing, synthetic-aperture processing with no corrections for surface variations, and synthetic-aperture processing with surface mapping. The unprocessed images have relatively poor lateral resolutions because echoes from two adjacent reflectors show interference effects which prevent their identification even if the spacing is larger than the single-hole resolution. The synthetic-aperture-processed images show at least a twofold improvement in lateral resolution and greatly reduced interference effects in multiple-hole images compared to directed-beam images. Perhaps more importantly, in images of test blocks with substantial surface variations portions of the image are displaced from their actual positions by several wavelengths. To correct for this effect an algorithm has been developed for calculating the surface variations. The corrected images produced using this algorithm are accurate within the experimental error. In addition, the same algorithm, when applied to the directed-beam data, produced images that are not only accurately positioned, but that also have a resolution comparable to conventional synthetic-aperture-processed images obtained from focused-transducer data. This suggests that using synthetic-aperture processing on the type of data normally collected during directed-beam ultrasonic inspections would eliminate the need to rescan for synthetic-aperture enhancement

  11. Polishing and toothbrushing alters the surface roughness and gloss of composite resins.

    Science.gov (United States)

    Kamonkhantikul, Krid; Arksornnukit, Mansuang; Takahashi, Hidekazu; Kanehira, Masafumi; Finger, Werner J

    2014-01-01

    This study aimed to investigate the surface roughness and gloss of composite resins after using two polishing systems and toothbrushing. Six composite resins (Durafill VS, Filtek Z250, Filtek Z350 XT, Kalore, Venus Diamond, and Venus Pearl) were evaluated after polishing with two polishing systems (Sof-Lex, Venus Supra) and after toothbrushing up to 40,000 cycles. Surface roughness (Ra) and gloss were determined for each composite resin group (n=6) after silicon carbide paper grinding, polishing, and toothbrushing. Two-way ANOVA indicated significant differences in both Ra and gloss between measuring stages for the composite resins tested, except Venus Pearl, which showed significant differences only in gloss. After polishing, the Filtek Z350 XT, Kalore, and Venus Diamond showed significant increases in Ra, while all composite resin groups except the Filtek Z350 XT and Durafill VS with Sof-Lex showed increases in gloss. After toothbrushing, all composite resin demonstrated increases in Ra and decreases in gloss.

  12. Multilayered nanoclusters of platinum and gold: insights on electrodeposition pathways, electrocatalysis, surface and bulk compositional properties

    CSIR Research Space (South Africa)

    Mkwizu, TS

    2013-06-01

    Full Text Available Electrochemical, surface and bulk compositional properties of multilayered nanoclusters of Pt and Au, electrochemically deposited on glassy carbon under conditions involving sequential surface–limited redox–replacement reactions (performed at open...

  13. Surface water connectivity drives richness and composition of Arctic lake fish assemblages

    Science.gov (United States)

    Laske, Sarah M.; Haynes, Trevor B.; Rosenberger, Amanda E.; Koch, Joshua C.; Wipfli, Mark S.; Whitman, Matthew; Zimmerman, Christian E.

    2016-01-01

    Surface water connectivity can influence the richness and composition of fish assemblages, particularly in harsh environments where colonisation factors and access to seasonal refugia are required for species persistence.

  14. Efficacy of polishing kits on the surface roughness and color stability of different composite resins.

    Science.gov (United States)

    Kocaagaoglu, H; Aslan, T; Gürbulak, A; Albayrak, H; Taşdemir, Z; Gumus, H

    2017-05-01

    Different polishing kits may have different effects on the composite resin surfaces. The aim of this study was to evaluate the surface roughness and color stability of four different composites which was applied different polishing technique. Thirty specimens were made for each composite resin group (nanohybrid, GrandioSo-GS; nanohybrid, Clearfil Majesty Esthetic-CME; hybrid, Valux Plus-VP; micro-hybrid, Ruby Comp-RC; [15 mm in diameter and 2 mm height]), with the different monomer composition and particle size from a total of 120 specimens. Each composite group was divided into three subgroups (n = 10). The first subgroup of the each composite subgroups served as control (C) and had no surface treatment. The second subgroup of the each composite resin groups was polished with finishing discs (Bisco Finishing Discs; Bisco Inc., Schaumburg, IL, USA). The third subgroup of the each composite resin was polished with polishing wheel (Enhance and PoGo, Dentsply, Konstanz, Germany). The surface roughness and the color differences measurement of the specimens were made and recorded. The data were compared using Kruskal-Wallis test, and regression analysis was used in order to examine the correlation between surface roughness and color differences of the specimens (α = 0.05). The Kruskal-Wallis test indicated significant difference among the composite resins in terms of ΔE (P composite resins in terms of surface roughness (P > 0.05). Result of the regression analysis indicated statistically significant correlation between Ra and ΔE values (P < 0.05, r2 = 0.74). The findings of the present study have clinical relevance in the choice of polishing kits used.

  15. Surface Roughness and Gloss of Actual Composites as Polished With Different Polishing Systems.

    Science.gov (United States)

    Rodrigues-Junior, S A; Chemin, P; Piaia, P P; Ferracane, J L

    2015-01-01

    This in vitro study evaluated the effect of polishing with different polishing systems on the surface roughness and gloss of commercial composites. One hundred disk-shaped specimens (10 mm in diameter × 2 mm thick) were made with Filtek P-90, Filtek Z350 XT, Opallis, and Grandio. The specimens were manually finished with #400 sandpaper and polished by a single operator using three multistep systems (Superfix, Diamond Pro, and Sof-lex), one two-step system (Polidores DFL), and one one-step system (Enhance), following the manufacturer's instructions. The average surface roughness (μm) was measured with a surface profilometer (TR 200 Surface Roughness Tester), and gloss was measured using a small-area glossmeter (Novo-Curve, Rhopoint Instrumentation, East Sussex, UK). Data were analyzed by two-way analysis of variance and Tukey's test (α=0.05). Statistically significant differences in surface roughness were identified by varying the polishing systems (pGloss was influenced by the composites (pone-step system, Enhance, produced the lowest gloss for all composites. Surface roughness and gloss were affected by composites and polishing systems. The interaction between both also influenced these surface characteristics, meaning that a single polishing system will not behave similarly for all composites. The multistep systems produced higher gloss, while the one-step system produced the highest surface roughness and the lowest gloss of all.

  16. Effects of 35% Carbamide Peroxide Gel on Surface Roughness and Hardness of Composite Resins

    OpenAIRE

    Sharafeddin, F.; Jamalipour, GR.

    2010-01-01

    Objective: Bleaching agents may not be safe for dental materials. The purpose of this in-vitro study was to evaluate the effects of Opalescent Quick ?in-office bleaching gel? containing 35% carbamide peroxide on the surface roughness and hardness of microfilled (Heliomolar) and hybride (Spectrum TPH) composite resins. Materials and Methods: Twenty specimens of Spectrum TPH composite resins and twenty Heliomolar composite resins were fabricated using a metallic ring (6.5 mm diameter and 2.5 mm...

  17. Simultaneous tuning of chemical composition and topography of copolymer surfaces: micelles as building blocks.

    Science.gov (United States)

    Zhao, Ning; Zhang, Xiaoyan; Zhang, Xiaoli; Xu, Jian

    2007-05-14

    A simple method is described for controlling the surface chemical composition and topography of the diblock copolymer poly(styrene)-b-poly(dimethylsiloxane)(PS-b-PDMS) by casting the copolymer solutions from solvents with different selectivities. The surface morphology and chemical composition were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively, and the wetting behavior was studied by water contact angle (CA) and sliding angle (SA) and by CA hysteresis. Chemical composition and morphology of the surface depend on solvent properties, humidity of the air, solution concentration, and block lengths. If the copolymer is cast from a common solvent, the resultant surface is hydrophobic, with a flat morphology, and dominated by PDMS on the air side. From a PDMS-selective solvent, the surface topography depends on the morphology of the micelles. Starlike micelles give rise to a featureless surface nearly completely covered by PDMS, while crew-cut-like micelles lead to a rough surface with a hierarchical structure that consists partly of PDMS. From a PS-selective solvent, however, surface segregation of PDMS was restricted, and the surface morphology can be controlled by vapor-induced phase separation. On the basis of the tunable surface roughness and PDMS concentration on the air side, water repellency of the copolymer surface could be tailored from hydrophobic to superhydrophobic. In addition, reversible switching behavior between hydrophobic and superhydrophobic can be achieved by exposing the surface to solvents with different selectivities.

  18. All-cellulose composites of regenerated cellulose fibres by surface selective dissolution

    NARCIS (Netherlands)

    Soykeabkaew, N.; Nishino, T.; Peijs, Ton

    2009-01-01

    All-cellulose composites of Lyocell and high modulus/strength cellulose fibres were successfully prepared using a surface selective dissolution method. The effect of immersion time of the fibres in the solvent during composite's preparation and the effect of the starting fibre's structure on their

  19. Effect of processing method on surface and weathering characteristics of wood-flour/HDPE composites

    Science.gov (United States)

    Nicole M. Stark; Laurent M. Matuana; Craig M. Clemons

    2004-01-01

    Wood-plastic lumber is promoted as a low maintenance high-durability product. When exposed to accelerated weathering, however, wood-plastic composites may experience a color change and/or loss in mechanical properties. Different methods of manufacturing wood-plastic composites lead to different surface characteristics, which can influence weathering, In this study, 50...

  20. The effect of different polishing systems on surface roughness and gloss of various resin composites.

    Science.gov (United States)

    Da Costa, Juliana; Ferracane, Jack; Paravina, Rade D; Mazur, Rui Fernando; Roeder, Leslie

    2007-01-01

    The purpose of this in vitro study was to evaluate the surface finish and gloss of five direct resin composites polished with six polishing systems. One hundred and fifty disk-shaped composite specimens (D=10.0 mm, 2-mm-thick, N=30 per material) were made. One side of each specimen was finished with a 16-fluted carbide finishing bur and then polished. Five specimens of each resin composite were randomly assigned to one of the six polishing systems. The surface roughness and gloss were measured with a surface profilometer and a glossmeter. The results were analyzed by two-way analysis of variance and Tukey's t-test (pgloss values between the composites and the polishing systems (p gloss value was recorded for Supreme + Pogo; the lowest was recorded for Z100 + Jiffy. Pogo showed the highest gloss values for all composites. The nanofill (Supreme) and minifill (Esthet-X) composites presented a surface roughness comparable to a microfill (Durafill), independent of the polishing system used, and a gloss comparable to a microfill, when polished with a one-step system (Pogo). As compared with the multiple-step systems, the smoothest surfaces and the highest gloss values were achieved using the one-step system (Pogo) for all the evaluated composites.

  1. Airport surface moving map displays: OpEval-2 evaluation results and future plans

    Science.gov (United States)

    Livack, Garret; McDaniel, James I.; Battiste, Vernol

    2001-08-01

    The Federal Aviation Administration (FAA), in cooperation with the Cargo Airline Association (CAA) and three of its member airlines (Airborne Express, Federal Express, and United Parcel Service), have embarked upon an aggressive yet phased approach to introduce new Free Flight-enabling technologies into the U.S. National Airspace System (NAS). General aviation is also actively involved, represented primarily by the Aircraft Owners and Pilots Association (AOPA). These new technologies being evaluated include advanced cockpit avionics and a complimentary ground infrastructure. In support of this initiative, a series of operational evaluations (OpEvals) have been conducted or are planned. The OpEvals have evaluated in-flight as well as airport surface movement applications. Results from the second OpEval, conducted at Louisville, Kentucky in October 2000, indicated that runway incursions might be significantly reduced with the introduction of a cockpit-based moving map system derived from emerging technologies. An additional OpEval is planned to evaluate the utility of an integrated cockpit and airport surface architecture that provides enhanced pilot and controller awareness of airport surface operations. It is believed that the combination of such an airborne and a ground-based system best addresses many of the safety issues surrounding airport surface operations. Such a combined system would provide both flight crews and controllers with a common awareness, or shared picture of airport surface operations.

  2. Mapping Global Ocean Surface Albedo from Satellite Observations: Models, Algorithms, and Datasets

    Science.gov (United States)

    Li, X.; Fan, X.; Yan, H.; Li, A.; Wang, M.; Qu, Y.

    2018-04-01

    Ocean surface albedo (OSA) is one of the important parameters in surface radiation budget (SRB). It is usually considered as a controlling factor of the heat exchange among the atmosphere and ocean. The temporal and spatial dynamics of OSA determine the energy absorption of upper level ocean water, and have influences on the oceanic currents, atmospheric circulations, and transportation of material and energy of hydrosphere. Therefore, various parameterizations and models have been developed for describing the dynamics of OSA. However, it has been demonstrated that the currently available OSA datasets cannot full fill the requirement of global climate change studies. In this study, we present a literature review on mapping global OSA from satellite observations. The models (parameterizations, the coupled ocean-atmosphere radiative transfer (COART), and the three component ocean water albedo (TCOWA)), algorithms (the estimation method based on reanalysis data, and the direct-estimation algorithm), and datasets (the cloud, albedo and radiation (CLARA) surface albedo product, dataset derived by the TCOWA model, and the global land surface satellite (GLASS) phase-2 surface broadband albedo product) of OSA have been discussed, separately.

  3. Surface roughness of orthodontic band cements with different compositions

    Directory of Open Access Journals (Sweden)

    Françoise Hélène van de Sande

    2011-06-01

    Full Text Available OBJECTIVES: The present study evaluated comparatively the surface roughness of four orthodontic band cements after storage in various solutions. MATERIAL AND METHODS: Eight standardized cylinders were made from 4 materials: zinc phosphate cement (ZP, compomer (C, resin-modified glass ionomer cement (RMGIC and resin cement (RC. Specimens were stored for 24 h in deionized water and immersed in saline (pH 7.0 or 0.1 M lactic acid solution (pH 4.0 for 15 days. Surface roughness readings were taken with a profilometer (Surfcorder SE1200 before and after the storage period. Data were analyzed by two-way ANOVA and Tukey's test (comparison among cements and storage solutions or paired t-test (comparison before and after the storage period at 5% significance level. RESULTS: The values for average surface roughness were statistically different (pRMGIC>C>R (p0.05. Compared to the current threshold (0.2 µm related to biofilm accumulation, both RC and C remained below the threshold, even after acidic challenge by immersion in lactic acid solution. CONCLUSIONS: Storage time and immersion in lactic acid solution increased the surface roughness of the majority of the tested cements. RC presented the smoothest surface and it was not influenced by storage conditions.

  4. Mapping Impervious Surfaces Globally at 30m Resolution Using Landsat Global Land Survey Data

    Science.gov (United States)

    Brown de Colstoun, E.; Huang, C.; Wolfe, R. E.; Tan, B.; Tilton, J.; Smith, S.; Phillips, J.; Wang, P.; Ling, P.; Zhan, J.; Xu, X.; Taylor, M. P.

    2013-12-01

    Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (~2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified

  5. The Properties of Nano Silver (Ag-Geopolymer as Antibacterial Composite for Functional Surface Materials

    Directory of Open Access Journals (Sweden)

    Armayani. M

    2017-01-01

    Full Text Available The purpose of this research was to produce and characterize nano silver (Ag-geopolymer composite for functional surface materials. Geopolymer matrix was synthesized through alkali activation of metakaolin and nano silver was added into geopolymers paste with a mass of 0, 0.5 g, 1 g, 1.5 g and 2 g keeping the mass of metakaolin constant. The mixture was cured at 70°C/1 hour and stored for 7 days before conducting any measurements. The structure of the resulting composite was examined by using Rigaku Mini Flex II x-ray diffraction (XRD. Scanning Electron Microscopy (SEM coupled with Energy Dispersive Spectroscopy (EDS was used to examine the morphology of the composite surface as well as the capability of the composite to isolate the growth of bacteria. The thermal properties of composites in terms of their working temperature and enthalpy were examined by using Perkin Elmer Differential Scanning Calorimetry (DSC. The heat resistance of composite was observed through calcination at 750°C for 18 hours. The results indicate that the resulting composites were able resist up 750°C. SEM examinations showed that nano Ag-geopolymer composites were effectively restraining the growth of bacteria. It is suggested that nano Ag-geopolymer composites are suitable for functional surface applications such as floor and wall, kitchen ware utensils, hospital instruments, art and decoration materials.

  6. Experimental Investigation and Analysis of Mercerized and Citric Acid Surface Treated Bamboo Fiber Reinforced Composite

    Science.gov (United States)

    De, Jyotiraman; Baxi, R. N., Dr.

    2017-08-01

    Mercerization or NaOH fiber surface treatment is one of the most popular surface treatment processes to make the natural fibers such as bamboo fibers compatible for use as reinforcing material in composites. But NaOH being a chemical is hazardous and polluting to the nature. This paper explores the possibility of use of naturally derived citric acid for bamboo fiber surface treatment and its comparison with NaOH treated Bamboo Fiber Composites. Untreated, 2.5 wt% NaOH treated and 5 wt% citric acid treated Bamboo Fiber Composites with 5 wt% fiber content were developed by Hand Lay process. Bamboo mats made of bamboo slivers were used as reinforcing material. Mechanical and physical characterization was done to compare the effects of NaOH and citric acid bamboo fiber surface treatment on mechanical and physical properties of Bamboo Fiber Composite. The experiment data reveals that the tensile and flexural strength was found to be highest for citric acid and NaOH treated Bamboo Fiber Composite respectively. Water absorption tendency was found more than the NaOH treated Bamboo Fiber Composites. SEM micrographs used to analyze the morphology of fracture surface of tensile test specimens confirm improvement in fiber-matrix interface bonding due to surface treatment of bamboo fibers.

  7. Surface Composition Near the Trailing Hemisphere Apex on Europa: The Manannán Impact Crater and Neighboring Terrain

    Science.gov (United States)

    Dalton, J. B.; Prockter, L. M.; Shirley, J. H.; Kamp, L.; Phillips, C. B.; Valenti, M.

    2012-12-01

    The Manannán impact crater and surrounding areas were imaged by Galileo's Near Infrared Mapping Spectrometer (NIMS) during the C3 orbital encounter. We have applied a linear mixture model based on cryogenic infrared reflectance spectroscopy to a "despiked" version of this NIMS observation (C3ENLINEA01A) to estimate abundances of sulfuric acid hydrate, hydrated sulfate salts, water ice and brines in surface exposures. Here we supplement our previously reported abundance estimates (Dalton et al., 2011) with additional results from our ongoing investigation. New geologic mapping precisely registered to the NIMS observation allows the extraction of high-quality near-infrared spectra specific to individual geologic units and morphological features. Detailed high resolution geologic mapping indicates the likely presence of extensive deposits of impact melt materials largely filling the crater floor (Moore et al. 2001), together with surrounding continuous ejecta deposits that may have been excavated from Europa's interior. We find that the crater floor and nearby ejecta exhibit low sulfuric acid abundance relative to the surroundings, with the abundance increasing with radial distance. Where the ejecta begins to thin and break up, the spectral mixture resembles a combination of pre-existing, high-acid-content materials and cleaner, excavated water ice. Several geologic units exhibit significantly lower sulfuric acid hydrate than expected for this region near the trailing hemisphere apex, varying from 53-64 wt% over the observation. This suggests that these surface units have received a reduced cumulative radiation dose (electrons and ions) compared to nearby terrain; this in turn implies geologic youth. We will present model compositions for several of Manannán's key stratigraphic units, including the crater floor deposits and the adjacent chaos and linea. We will interpret these results in the context of ongoing investigations of the interplay of exogenic and

  8. MCO gas composition for low reactive surface areas

    International Nuclear Information System (INIS)

    Packer, M.J.

    1998-01-01

    This calculation adjusts modeled output (HNF-SD-SNF-TI-040, Rev. 2) by considering lower reactive fuel surface areas and by increasing the input helium backfill overpressure from 0.5 to 1.5 atm (2.5 atm abs) to verify that MCO gas-phase oxygen concentrations can remain below 4 mole % over a 40 year interim period under a worst case condition of zero reactive surface area. Added backfill gas will dilute any gases generated during interim storage and is a strategy within the current design capability. The zero reactive surface area represents a hypothetical worst case example where there is no fuel scrap and/or damaged spent fuel rods in an MCO. Also included is a hypothetical case where only K East fuel exists in an MCO with an added backfill overpressure of 0.5 atm (1.5 atm abs)

  9. A new method for automated discontinuity trace mapping on rock mass 3D surface model

    Science.gov (United States)

    Li, Xiaojun; Chen, Jianqin; Zhu, Hehua

    2016-04-01

    This paper presents an automated discontinuity trace mapping method on a 3D surface model of rock mass. Feature points of discontinuity traces are first detected using the Normal Tensor Voting Theory, which is robust to noisy point cloud data. Discontinuity traces are then extracted from feature points in four steps: (1) trace feature point grouping, (2) trace segment growth, (3) trace segment connection, and (4) redundant trace segment removal. A sensitivity analysis is conducted to identify optimal values for the parameters used in the proposed method. The optimal triangular mesh element size is between 5 cm and 6 cm; the angle threshold in the trace segment growth step is between 70° and 90°; the angle threshold in the trace segment connection step is between 50° and 70°, and the distance threshold should be at least 15 times the mean triangular mesh element size. The method is applied to the excavation face trace mapping of a drill-and-blast tunnel. The results show that the proposed discontinuity trace mapping method is fast and effective and could be used as a supplement to traditional direct measurement of discontinuity traces.

  10. Agriculture pest and disease risk maps considering MSG satellite data and land surface temperature

    Science.gov (United States)

    Marques da Silva, J. R.; Damásio, C. V.; Sousa, A. M. O.; Bugalho, L.; Pessanha, L.; Quaresma, P.

    2015-06-01

    Pest risk maps for agricultural use are usually constructed from data obtained from in-situ meteorological weather stations, which are relatively sparsely distributed and are often quite expensive to install and difficult to maintain. This leads to the creation of maps with relatively low spatial resolution, which are very much dependent on interpolation methodologies. Considering that agricultural applications typically require a more detailed scale analysis than has traditionally been available, remote sensing technology can offer better monitoring at increasing spatial and temporal resolutions, thereby, improving pest management results and reducing costs. This article uses ground temperature, or land surface temperature (LST), data distributed by EUMETSAT/LSASAF (with a spatial resolution of 3 × 3 km (nadir resolution) and a revisiting time of 15 min) to generate one of the most commonly used parameters in pest modeling and monitoring: "thermal integral over air temperature (accumulated degree-days)". The results show a clear association between the accumulated LST values over a threshold and the accumulated values computed from meteorological stations over the same threshold (specific to a particular tomato pest). The results are very promising and enable the production of risk maps for agricultural pests with a degree of spatial and temporal detail that is difficult to achieve using in-situ meteorological stations.

  11. Descriptive Characteristics of Surface Water Quality in Hong Kong by a Self-Organising Map

    Directory of Open Access Journals (Sweden)

    Yan An

    2016-01-01

    Full Text Available In this study, principal component analysis (PCA and a self-organising map (SOM were used to analyse a complex dataset obtained from the river water monitoring stations in the Tolo Harbor and Channel Water Control Zone (Hong Kong, covering the period of 2009–2011. PCA was initially applied to identify the principal components (PCs among the nonlinear and complex surface water quality parameters. SOM followed PCA, and was implemented to analyze the complex relationships and behaviors of the parameters. The results reveal that PCA reduced the multidimensional parameters to four significant PCs which are combinations of the original ones. The positive and inverse relationships of the parameters were shown explicitly by pattern analysis in the component planes. It was found that PCA and SOM are efficient tools to capture and analyze the behavior of multivariable, complex, and nonlinear related surface water quality data.

  12. Descriptive Characteristics of Surface Water Quality in Hong Kong by a Self-Organising Map.

    Science.gov (United States)

    An, Yan; Zou, Zhihong; Li, Ranran

    2016-01-08

    In this study, principal component analysis (PCA) and a self-organising map (SOM) were used to analyse a complex dataset obtained from the river water monitoring stations in the Tolo Harbor and Channel Water Control Zone (Hong Kong), covering the period of 2009-2011. PCA was initially applied to identify the principal components (PCs) among the nonlinear and complex surface water quality parameters. SOM followed PCA, and was implemented to analyze the complex relationships and behaviors of the parameters. The results reveal that PCA reduced the multidimensional parameters to four significant PCs which are combinations of the original ones. The positive and inverse relationships of the parameters were shown explicitly by pattern analysis in the component planes. It was found that PCA and SOM are efficient tools to capture and analyze the behavior of multivariable, complex, and nonlinear related surface water quality data.

  13. Variation in skin surface lipid composition among the Equidae.

    Science.gov (United States)

    Colton, S W; Downing, D T

    1983-01-01

    Skin surface lipids from Equus caballus, E. przewalskii, E. asinus, E. grevyi, E. hemionus onager and a mule (E. asinus/E. caballus) were analyzed in detail. In all species the surface lipid mixtures consisted of giant-ring lactones, cholesterol, cholesteryl esters and minor amounts of wax diesters. In E. caballus, the lactone hydroxyacids were entirely branched chained, while in E. asinus and E. grevyi they were almost exclusively straight chained. In E. przewalskii, the onager and the mule there were both straight and branched chain hydroxyacid lactones. These results are in harmony with published interpretations of the evolutionary relationships among Equus species.

  14. Cell behavior related to implant surfaces with different microstructure and chemical composition: an in vitro analysis.

    Science.gov (United States)

    Conserva, Enrico; Lanuti, Anna; Menini, Maria

    2010-01-01

    This paper reports on an in vitro comparison of osteoblast and mesenchymal stem cell (MSC) adhesion, proliferation, and differentiation related to two different surface treatments applied to the same implant design to determine whether the interaction between cells and implants is influenced by surface structure and chemical composition of the implants. Thirty-nine implants with a sandblasted (SB) surface and 39 implants with a grit-blasted and high-temperature acid-etched (GBAE) surface were used. The implant macrostructures and microstructures were analyzed by high- and low-voltage scanning electron microscopy (SEM) and by stereo-SEM. The surface chemical composition was investigated by energy dispersive analysis and x-ray photoemission spectroscopy. SaOS-2 osteoblasts and human MSCs were used for the evaluation of cell proliferation and alkaline phosphatase enzymatic activity in contact with the two surfaces. The GBAE surface showed fewer contaminants and a very high percentage of titanium (19.7%) compared to the SB surface (14.2%). The two surfaces showed similar mean roughness (Ra), but the depth (Rz) and density (RSm) of the porosity were significantly increased in the GBAE surface. The GBAE surface presented more osteoblast and MSC proliferation than the SB surface. No statistically significant differences in alkaline phosphatase activity were found between surfaces for either cellular line. The GBAE surface showed less surface contaminants and a higher percentage of titanium (19.7%) than the SB surface. The macro/micropore structured design and chemical composition of the GBAE surface allowed greater cell adhesion and proliferation and an earlier cell spreading but did not play an obvious role in in vitro cellular differentiation.

  15. Effect of sealant agents on the color stability and surface roughness of nanohybrid composite resins.

    Science.gov (United States)

    Dede, Doğu Ömür; Şahin, Onur; Koroglu, Aysegül; Yilmaz, Burak

    2016-07-01

    The effect of sealant agents on the surface roughness and color stability of nanohybrid composite resins is unknown. The purpose of this in vitro study was to evaluate the effect of sealant agents on the surface roughness and color stability of 4 nanohybrid composite resin materials. Forty disks (10×2 mm) were fabricated for each nanohybrid composite resin material (Z-550, Tetric EvoCeram, Clearfill Majesty, Ice) (N=160) and divided into 4 surface treatment groups: 1 conventional polishing (control) and 3 different sealant agent (Palaseal, Optiglaze, BisCover) coupling groups (n=10). The specimens were thermocycled, and surface roughness (Ra) values were obtained with a profilometer. Scanning electron microscope images were also recorded. CIELab color parameters of each specimen were measured with a spectrophotometer before and after 7 days of storage in a coffee solution. Color differences were calculated by the CIEDE 2000 (ΔE00) formula. The data were statistically analyzed by 2-way ANOVA and by the Tukey HSD test (α=.05). The surface treatment technique significantly affected the Ra values of the composite resins tested (Pcomposite resin material was also significant for ΔE00 values (Pcomposite resin groups, significant decreases in Ra were observed only for the Palaseal agent coupled composite resin groups (except Ice) compared with the control groups (Pcomposite resin group, except for BisCover applied Clearfill Majesty (Pcomposite resin groups, significant differences were observed between the color change seen with BisCover and other sealants for Clearfill Majesty composite resin (Pcomposite resins except for Ice produced smoother surfaces. All surface sealant agents provided less discoloration of nanohybrid composite resins after coffee staining compared with conventional polishing except for BisCover applied Clearfill Majesty composite resin. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All

  16. A Surface Soil Radioactivity Mapping Has Been Carried Out at Muria Peninsula, Central Java

    International Nuclear Information System (INIS)

    Soepradto-Tjokrokardono; Nasrun-Syamsul; Supardjo-AS; Djodi-R-Mappa; Kurnia-Setyawan W

    2004-01-01

    The air of this mapping is to gain exposure dose value of the soil surface of Muria Peninsula. Central Java, in the area of 75 km radius from Ujung Lemah Abang. Lemah Abang is the proposed site of the first indonesian nuclear Power Plant. A radioactivity data obtained in 1995/1996 to 1998/1999 researches has been used for input data. For further analysis, a conversation factor multiplication is applied. This conversation factor is obtained from linear regression equation of the relationship between radioactivity and exposure values gained from re-measured randomly 44 points which are representative for high, medium, and low radiation areas obtained in 1995/1996 to 1998/1999 activities and it taking soil samples. The conversation data result is being constructed of the Surface Exposure Dose Map of Muria Peninsula. Those data show that the exposure dose of northern slope of Muria Volcano is relatively higher than that of southern slope, it means be harmonizing to the soil sample radioactivity values. The maximum radioactivity value of the soil samples is 3,56.10 -2 Bq/gram (α radiation), 8,22.10 -1 Bq/gram (β radiation) and 6,20.10 -1 Bq/gram (γ radiation) and the minimum values are 4,44 10 -3 Bq/gram (α radiation), 1,50. 10 -1 Bq/gram (β radiation) and 4,09. 10 -2 Bq/gram (γ radiation). (author)

  17. A new capture fraction method to map how pumpage affects surface water flow

    Science.gov (United States)

    Leake, S.A.; Reeves, H.W.; Dickinson, J.E.

    2010-01-01

    All groundwater pumped is balanced by removal of water somewhere, initially from storage in the aquifer and later from capture in the form of increase in recharge and decrease in discharge. Capture that results in a loss of water in streams, rivers, and wetlands now is a concern in many parts of the United States. Hydrologists commonly use analytical and numerical approaches to study temporal variations in sources of water to wells for select points of interest. Much can be learned about coupled surface/groundwater systems, however, by looking at the spatial distribution of theoretical capture for select times of interest. Development of maps of capture requires (1) a reasonably well-constructed transient or steady state model of an aquifer with head-dependent flow boundaries representing surface water features or evapotranspiration and (2) an automated procedure to run the model repeatedly and extract results, each time with a well in a different location. This paper presents new methods for simulating and mapping capture using three-dimensional groundwater flow models and presents examples from Arizona, Oregon, and Michigan. Journal compilation ?? 2010 National Ground Water Association. No claim to original US government works.

  18. Magnetic surface mapping with highly transparent screens on the Auburn Torsatron

    International Nuclear Information System (INIS)

    Hartwell, G.J.; Gandy, R.F.; Henderson, M.A.; Hanson, J.D.; Swanson, D.G.; Bush, C.J.; Colchin, R.J.; England, A.C.; Lee, D.K.

    1987-01-01

    In stellarator-type magnetic confinement devices (of which the torsatron is one), the magnetic field is produced entirely by external, current-carrying coils. Two methods for mapping magnetic surfaces in the Auburn Torsatron were tested and compared, both of which involve the use of highly transparent screens. The first method consists of coating the screen with a phosphor that emits light when struck by electrons emitted by an electron gun. A pattern representative of a magnetic surface is formed on the screen, and this pattern is recorded photographically. The second method uses an uncoated screen to collect electrons emitted from an emissive probe, which is scanned over a poloidal cross section of the torus. Under certain conditions, the collected current is a constant over a particular magnetic surface so that a contour plot of the current versus position is equivalent to a plot of the magnetic surfaces. Parametric studies of the two methods are presented, and the effectiveness of each technique is discussed

  19. Effect of whitening dentifrices on the surface roughness of commercial composites.

    Science.gov (United States)

    Barbieri, Guilherme Machado; Mota, Eduardo Gonçalves; Rodrigues-Junior, Sinval Adalberto; Burnett, Luiz Henrique

    2011-10-01

    Our study aimed to test the null hypothesis that whitening and non-whitening dentifrices affect similarly the surface roughness of commercial microhybrid composites, independent of the brushing time. One hundred and ninety-two disc-shaped specimens of Filtek Z250 (3 M/ESPE, St. Paul, MN, USA) and Rok (SDI, Australia) were built up and randomly assigned to 24 groups, based on the dentifrices used (two whitening dentifrices: Colgate Max White-Colgate-Palmolive, São Bernardo do Campo, São Paulo, Brazil and Close Up Extra Whitening-Unilever, Brasil Higiene Pessoal e Limpeza Ltda, Ipojuca, Pernambuco, Brazil; and one non-whitening dentifrice: Colgate Total 12 Clean Mint-Colgate-Palmolive), and on the simulated brushing times (24 hours, 6, 12 and 24 months). The specimens were submitted to the toothbrushing regimens after which the surface roughness (Ra) was measured. Data was submitted to analysis of variance and Tukey test (α=0.05). The composite's surface roughness was significantly affected by the composites (p=0.0007), the dentifrices (p=0.0001), and the simulated brushing time (p=0.0001). Higher roughness was observed when the whitening dentifrices were used and when the brushing time increased. Filtek Z250 was more affected than Rok, especially after 24 months of simulated brushing. Whitening dentifrices produced higher surface roughness in the composites tested. The degree of surface compromising increased with brushing time and depends on the composite's microstructure and composition. © 2011 Wiley Periodicals, Inc.

  20. [Comparison of surface roughness of nanofilled and microhybrid composite resins after curing and polishing].

    Science.gov (United States)

    Jiang, Hong; Lv, Da; Liu, Kailei; Zhang, Weisheng; Yao, Yao; Liao, Chuhong

    2014-05-01

    To compare the surface roughness of nanofilled dental composite resin and microhybrid composite resins after curing and polishing. A nanofilled composite (Z350) and 4 microhybrid composites (P60, Z250, Spectrum, and AP-X) were fabricated from the lateral to the medial layers to prepare 8 mm×8 mm×5 mm cubical specimens. The 4 lateral surfaces of each specimens were polished with abrasive disks (Super-Snap). Profilometer was used to test the mean surface roughness (Ra) after polishing. P60 had the lowest Ra (0.125∓0.030 µm) followed by Z250 and Spectrum. The Ra of Z350 (0.205∓0.052 µm) was greater than that of the other 3 resins, and AP-X had the roughest surfaces. Under scanning electron microscope, the polished faces of P60 resin were characterized by minor, evenly distributed particles with fewer scratches; the polished faces of Z350 presented with scratches where defects of the filling material could be seen. The nanofilled composite Z350 has smooth surface after polishing by abrasive disks, but its smoothness remains inferior to that of other micro-hybrid composite resins.

  1. In vitro study of Streptococcus mutans adhesion on composite resin coated with three surface sealants

    Directory of Open Access Journals (Sweden)

    Da Hye Kim

    2017-02-01

    Full Text Available Objectives Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans on the dental composite resins coated with three commercial surface sealants. Materials and Methods Composite resin (Filtek Z250 discs (8 mm in diameter, 1 mm in thickness were fabricated in a mold covered with a Mylar strip (control. In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP. The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9. Results Group OG achieved the lowest water contact angle among all groups tested (p 0.05 or significantly lower (group OG, p < 0.001 bacterial adhesion when compared with the control group. Conclusions The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo.

  2. Appearance of anodised aluminium: Effect of alloy composition and prior surface finish

    DEFF Research Database (Denmark)

    Aggerbeck, Martin; Canulescu, Stela; Dirscherl, Kai

    2014-01-01

    Effect of alloy composition and prior surface finish on the optical appearance of the anodised layer on aluminium alloys was investigated. Four commercial alloys namely AA1050, Peraluman 706, AA5754, and AA6082 were used for the investigation. Microstructure and surface morphology of the substrat...

  3. Surface roughness of composite resin veneer after application of herbal and non-herbal toothpaste

    Science.gov (United States)

    Nuraini, S.; Herda, E.; Irawan, B.

    2017-08-01

    The aim of this study was to find out the surface roughness of composite resin veneer after brushing. In this study, 24 specimens of composite resin veneer are divided into three subgroups: brushed without toothpaste, brushed with non-herbal toothpaste, and brushed with herbal toothpaste. Brushing was performed for one set of 5,000 strokes and continued for a second set of 5,000 strokes. Roughness of composite resin veneer was determined using a Surface Roughness Tester. The results were statistically analyzed using Kruskal-Wallis nonparametric test and Post Hoc Mann-Whitney. The results indicate that the highest difference among the Ra values occurred within the subgroup that was brushed with the herbal toothpaste. In conclusion, the herbal toothpaste produced a rougher surface on composite resin veneer compared to non-herbal toothpaste.

  4. Thermal, spectral, and surface properties of LED light-polymerized bulk fill resin composites.

    Science.gov (United States)

    Pişkin, Mehmet Burçin; Atalı, Pınar Yılmaz; Figen, Aysel Kantürk

    2015-02-01

    The aim of this study was to evaluate the thermal, spectral, and surface properties of four different bulk fill materials – SureFil SDR (SDR, Dentsplay DETREY), QuixFil (QF, Dentsplay DETREY), X-tra base (XB, Voco) X-tra fil (XF, Voco) – polymerized by light-emitting diode (LED). Resin matrix, filler type, size and amount, and photoinitiator types influence the degree of conversion. LED-cured bulk fill composites achieved sufficient polymerization. Scanning electron microscope (SEM) analysis revealed different patterns of surface roughness, depending on the composite material. Bulk fill materials showed surface characteristics similar to those of nanohybrid composites. Based on the thermal analysis results, glass transition (T(g)) and initial degradation (T(i)) temperatures changed depending on the bulk fill resin composites.

  5. Effect of surface treatments on the bond strengths of facing composite resins to zirconia copings.

    Science.gov (United States)

    Tsumita, M; Kokubo, Y; Kano, T

    2012-09-01

    The present study evaluated and compared the bond strength between zirconia and facing composite resin using different surface conditioning methods before and after thermocycling. Four primers, three opaque resins, and two facing composite resins were used, and 10 surface treatment procedures were conducted. The bond strength was measured before and after 4,000 cycles of thermocycling. The mean values of each group were statistically analyzed using one-way analysis of variance (ANOVA). The bond strengths of facing composite resins to zirconia after various treatments varied depending on the primers, opaque resins, body resins, and thermocycling. The application of primers and opaque resins to the zirconia surface after sandblasting is expected to yield strong bond strength of the facing composite resin (Estenia CG&B) even after thermocycling.

  6. Association Mapping of Biomass Yield and Stem Composition in a Tetraploid Alfalfa Breeding Population

    Directory of Open Access Journals (Sweden)

    Xuehui Li

    2011-03-01

    Full Text Available Alfalfa ( L., an important forage crop that is also a potential biofuel crop, has advantages of high yield, high lignocellulose concentration in stems, and has low input costs. In this study, we investigated population structure and linkage disequilibrium (LD patterns in a tetraploid alfalfa breeding population using genome-wide simple sequence repeat (SSR markers and identified markers related to yield and cell wall composition by association mapping. No obvious population structure was found in our alfalfa breeding population, which could be due to the relatively narrow genetic base of the founders and/or due to two generations of random mating. We found significant LD ( 10% alleles across the 71 SSR markers, 15 showed strong association ( < 0.005 with yield in at least one of five environments, and most of the 15 alleles were identified in multiple environments. Only one allele showed strong association with acid detergent fiber (ADF and one allele with acid detergent lignin (ADL. Alleles associated with traits could be directly applied in a breeding program using marker-assisted selection. However, based on our estimated LD level, we would need about 1000 markers to explore the whole alfalfa genome for association between markers and traits.

  7. Surface compositions in the Aristarchus Region: Implications for regional stratigraphy

    Science.gov (United States)

    Hawke, H. R.; Lucey, P. G.; Mccord, T. B.; Pieters, C. M.; Head, J. W.

    1984-01-01

    Near infrared reflectance spectra for the Aristachus region, obtained using the 2.2m UH telescope at the Mauna Kea Observatory, were reduced and analyzed. The spectra obtained for the central peak, southern floor, southwestern wall, eastern wall, and northwestern wall of Aristachus crater exhibit shallow continuum slopes, relatively strong feldspar bands, pyroxene bands stronger than those typically seen in the spectra of fresh higland features, and pyroxene band centers near l micrometer suggesting the dominance of Ca rich clinopyroxene. The spectrum of the south rim of Aristachus is quite distinct from those of other crater units. The position of Aristrchus on the plateau/mare boundary raises questions concerning compositional variations in crater ejects deposits.

  8. Generation of H-, D- ions on composite surfaces with application to surface/plasma ion source systems

    International Nuclear Information System (INIS)

    Hiskes, J.R.; Karo, A.M.; Wimmer, E.; Freeman, A.J.; Chubb, S.R.

    1983-01-01

    We review some salient features of the experimental and theoretical data pertaining to hydrogen negative ion generation on minimum-work-function composite surfaces consisting of Cs/transition metal substrates. Cesium or hydrogen ion bombardment of a cesium-activated negatively-biased electrode exposed to a cesium-hydrogen discharge results in the release of hydrogen negative ions. These ions originate through desorbtion of hydrogen particles by incident cesium ions, desorbtion by incident hydrogen ions, and by backscattering of incident hydrogen. Each process is characterized by a specific energy and angular distribution. The calculation of ion formation in the crystal selvage region is discussed for different approximations to the surface potential. An ab initio, all-electron, local density functional model for the composite surface electronics is discussed

  9. Biofilm formation affects surface properties of novel bioactive glass-containing composites.

    Science.gov (United States)

    Hyun, Hong-Keun; Salehi, Satin; Ferracane, Jack L

    2015-12-01

    This study investigated the effects of bacterial biofilm on the surface properties of novel bioactive glass (BAG)-containing composites of different initial surface roughness. BAG (65 mol% Si; 4% P; 31% Ca) and BAG-F (61% Si; 31% Ca; 4% P; 3% F; 1% B) were synthesized by the sol-gel method and micronized (size ∼0.1-10 μm). Composites with 72wt% total filler load were prepared by replacing 15% of the silanized Sr glass with BAG, BAG-F, or silanized silica. Specimens (n=10/group) were light-cured and divided into 4 subgroups of different surface roughness by wet polishing with 600 and then up to 1200, 2400, or 4000 grit SiC. Surface roughness (SR), gloss, and Knoop microhardness were measured before and after incubating in media with or without a Streptococcus mutans (UA 159) biofilm for 2 weeks. Results were analyzed with ANOVA/Tukey's test (α=0.05). The SR of the BAG-containing composites with the smoothest surfaces (2400/4000 grit) increased in media or bacteria; the SR of the roughest composites (600 grit) decreased. The gloss of the smoothest BAG-containing composites decreased in bacteria and media-only, but more in media-alone. The microhardness of all of the composites decreased with exposure to media or bacteria, with BAG-containing composites affected more than the control. Exposure to bacterial biofilm and its media produced enhanced roughness and reduced gloss and surface microhardness of highly polished dental composites containing a bioactive glass additive, which could affect further biofilm formation, as well as the esthetics, of restorations made from such a material. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  10. Effect of Various Surface Treatment on Repair Strength of Composite Resin

    Directory of Open Access Journals (Sweden)

    Y. Alizade

    2004-12-01

    Full Text Available Statement of Problem: In some clinical situations, repair of composite restorations is treatment of choice. Improving the bond strength between one new and old composite usually requires increased surface roughness to promote mechanical interlocking sincechemical bonding might not be adequate. Similarly, the treatment of a laboratory fabricated resin composite restoration involves the same procedures, and there is a need to create the strongest possible bond of a resin cement to a previously polymerized composite.Purpose: The aim of this study was to evaluate the effect of various surface treatments on the shear bond strength of repaired to aged composite resin.Materials and Methods: Eighty four cylindrical specimens of a composite resin were fabricated and stored in distilled water for 100 days prior to surface treatment. Surface treatment of old composite was done in 6 groups as follow:1- Air abrasion with CoJet sand particles with micoretcher + silane + dentin bonding agent2- Air abrasion with 50μm Al2O3 particles+ phosphoric acid+ silane+ dentin bonding agent3- Air abrasion with 50μm Al2O3 particles + phosphoric acid + dentin bonding agent4- Diamond bur + phosphoric acid + silane + dentin bonding agent5- Diamond bur + phosphoric acid + dentin bonding agent6- Diamond bur + phosphoric acid + composite activator + dentin bonding agentThen fresh composite resin was bonded to treated surfaces. Twelve specimens were also fabricated as control group with the same diameter but with the height twice as much as other specimens. All of the specimens were thermocycled prior to testing for shear bondstrength. The bond strength data were analyzed statistically using one way ANOVA test, t test and Duncan's grouping test.Results: One-way ANOVA indicated no significant difference between 7 groups (P=0.059. One-way ANOVA indicated significant difference between the three diamond bur groups (P=0.036. Silane had a significant effect on the repair bond

  11. Vectorial mapping of noncollinear antiferromagnetic structure of semiconducting FeSe surface with spin-polarized scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, K. F.; Yang, Fang; Song, Y. R. [Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhang, Xiaole [Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240 (China); The State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Chen, Xianfeng [The State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Liu, Canhua; Qian, Dong; Gao, C. L., E-mail: clgao@sjtu.edu.cn; Jia, Jin-Feng [Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing (China); Luo, Weidong, E-mail: wdluo@sjtu.edu.cn [Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing (China)

    2016-02-08

    Antiferromagnetic semiconductors gain increasing interest due to their possible application in spintronics. Using spin polarized scanning tunneling microscopy operating in a vector field, we mapped the noncollinear antiferromagnetic spin structure of a semiconducting hexagonal FeSe surface on the atomic scale. The surface possesses an in-plane compensated Néel structure which is further confirmed by first-principles calculations.

  12. Vectorial mapping of noncollinear antiferromagnetic structure of semiconducting FeSe surface with spin-polarized scanning tunneling microscopy

    International Nuclear Information System (INIS)

    Zhang, K. F.; Yang, Fang; Song, Y. R.; Zhang, Xiaole; Chen, Xianfeng; Liu, Canhua; Qian, Dong; Gao, C. L.; Jia, Jin-Feng; Luo, Weidong

    2016-01-01

    Antiferromagnetic semiconductors gain increasing interest due to their possible application in spintronics. Using spin polarized scanning tunneling microscopy operating in a vector field, we mapped the noncollinear antiferromagnetic spin structure of a semiconducting hexagonal FeSe surface on the atomic scale. The surface possesses an in-plane compensated Néel structure which is further confirmed by first-principles calculations

  13. Compositions of stone and stone surface materials of historical monuments from Vidzeme and Zemgale

    International Nuclear Information System (INIS)

    Actins, A.; Spricis, A.; Zekunde, A.; Nemerova, A.

    2004-01-01

    By means of x-ray analysis composition of stone and stone surface materials of historical monuments from Vidzeme and Zemgale was investigated. Corrosion products of tuffa materials were identified on surfaces of some investigated monuments. Similarity of composition of products of stone corrosion for monuments from Latvia and Poland was recognised. Content of heavy metals at stone materials of historical monuments and at the surface layers of these monuments was investigated by means of atomic absorption and potentiometric stripping methods. Reasons of formation of compounds and pollution of investigated samples were discussed. (full text)

  14. Surface density mapping of natural tissue by a scanning haptic microscope (SHM).

    Science.gov (United States)

    Moriwaki, Takeshi; Oie, Tomonori; Takamizawa, Keiichi; Murayama, Yoshinobu; Fukuda, Toru; Omata, Sadao; Nakayama, Yasuhide

    2013-02-01

    To expand the performance capacity of the scanning haptic microscope (SHM) beyond surface mapping microscopy of elastic modulus or topography, surface density mapping of a natural tissue was performed by applying a measurement theory of SHM, in which a frequency change occurs upon contact of the sample surface with the SHM sensor - a microtactile sensor (MTS) that vibrates at a pre-determined constant oscillation frequency. This change was mainly stiffness-dependent at a low oscillation frequency and density-dependent at a high oscillation frequency. Two paragon examples with extremely different densities but similar macroscopic elastic moduli in the range of natural soft tissues were selected: one was agar hydrogels and the other silicon organogels with extremely low (less than 25 mg/cm(3)) and high densities (ca. 1300 mg/cm(3)), respectively. Measurements were performed in saline solution near the second-order resonance frequency, which led to the elastic modulus, and near the third-order resonance frequency. There was little difference in the frequency changes between the two resonance frequencies in agar gels. In contrast, in silicone gels, a large frequency change by MTS contact was observed near the third-order resonance frequency, indicating that the frequency change near the third-order resonance frequency reflected changes in both density and elastic modulus. Therefore, a density image of the canine aortic wall was subsequently obtained by subtracting the image observed near the second-order resonance frequency from that near the third-order resonance frequency. The elastin-rich region had a higher density than the collagen-rich region.

  15. Mining for diagnostic information in body surface potential maps: A comparison of feature selection techniques

    Directory of Open Access Journals (Sweden)

    McCullagh Paul J

    2005-09-01

    Full Text Available Abstract Background In body surface potential mapping, increased spatial sampling is used to allow more accurate detection of a cardiac abnormality. Although diagnostically superior to more conventional electrocardiographic techniques, the perceived complexity of the Body Surface Potential Map (BSPM acquisition process has prohibited its acceptance in clinical practice. For this reason there is an interest in striking a compromise between the minimum number of electrocardiographic recording sites required to sample the maximum electrocardiographic information. Methods In the current study, several techniques widely used in the domains of data mining and knowledge discovery have been employed to mine for diagnostic information in 192 lead BSPMs. In particular, the Single Variable Classifier (SVC based filter and Sequential Forward Selection (SFS based wrapper approaches to feature selection have been implemented and evaluated. Using a set of recordings from 116 subjects, the diagnostic ability of subsets of 3, 6, 9, 12, 24 and 32 electrocardiographic recording sites have been evaluated based on their ability to correctly asses the presence or absence of Myocardial Infarction (MI. Results It was observed that the wrapper approach, using sequential forward selection and a 5 nearest neighbour classifier, was capable of choosing a set of 24 recording sites that could correctly classify 82.8% of BSPMs. Although the filter method performed slightly less favourably, the performance was comparable with a classification accuracy of 79.3%. In addition, experiments were conducted to show how (a features chosen using the wrapper approach were specific to the classifier used in the selection model, and (b lead subsets chosen were not necessarily unique. Conclusion It was concluded that both the filter and wrapper approaches adopted were suitable for guiding the choice of recording sites useful for determining the presence of MI. It should be noted however

  16. An improved method for Multipath Hemispherical Map (MHM) based on Trend Surface Analysis

    Science.gov (United States)

    Wang, Zhiren; Chen, Wen; Dong, Danan; Yu, Chao

    2017-04-01

    Among various approaches developed for detecting the multipath effect in high-accuracy GNSS positioning, Only MHM (Multipath Hemispherical Map) and SF (Sidereal Filtering) can be implemented to real-time GNSS data processing. SF is based on the time repeatability of satellites which just suitable for static environment, while the spatiotemporal repeatability-based MHM is applicable not only for static environment but also for dynamic carriers with static multipath environment such as ships and airplanes, and utilizes much smaller number of parameters than ASF. However, the MHM method also has certain defects. Since the MHM take the mean of residuals from the grid as the filter value, it is more suitable when the multipath regime is medium to low frequency. Now existing research data indicate that the newly advanced Sidereal Filtering (ASF) method perform better with high frequency multipath reduction than MHM by contrast. To solve the above problem and improve MHM's performance on high frequency multipath, we combined binary trend surface analysis method with original MHM model to effectively analyze particular spatial distribution and variation trends of multipath effect. We computed trend surfaces of the residuals within a grid by least-square procedures, and chose the best results through the moderate successive test. The enhanced MHM grid was constructed from a set of coefficients of the fitted equation instead of mean value. According to the analysis of the actual observation, the improved MHM model shows positive effect on high frequency multipath reduction, and significantly reduced the root mean square (RMS) value of the carrier residuals. Keywords: Trend Surface Analysis; Multipath Hemispherical Map; high frequency multipath effect

  17. Characterization of boron carbide particulate reinforced in situ copper surface composites synthesized using friction stir processing

    Energy Technology Data Exchange (ETDEWEB)

    Sathiskumar, R., E-mail: sathiscit2011@gmail.com [Department of Mechanical Engineering, Coimbatore Institute of Technology, Coimbatore, 641 014 Tamil Nadu (India); Murugan, N., E-mail: murugan@cit.edu.in [Department of Mechanical Engineering, Coimbatore Institute of Technology, Coimbatore, 641 014 Tamil Nadu (India); Dinaharan, I., E-mail: dinaweld2009@gmail.com [Department of Mechanical Engineering, V V College of Engineering, Tisaiyanvilai, 627 657 Tamil Nadu (India); Vijay, S.J., E-mail: vijayjoseph@karunya.edu [Centre for Research in Metallurgy (CRM), School of Mechanical Sciences, Karunya University, Coimbatore, 641 114 Tamil Nadu (India)

    2013-10-15

    Friction stir processing has evolved as a novel solid state technique to fabricate surface composites. The objective of this work is to apply the friction stir processing technique to fabricate boron carbide particulate reinforced copper surface composites and investigate the effect of B{sub 4}C particles and its volume fraction on microstructure and sliding wear behavior of the same. A groove was prepared on 6 mm thick copper plates and packed with B{sub 4}C particles. The dimensions of the groove was varied to result in five different volume fractions of B{sub 4}C particles (0, 6, 12, 18 and 24 vol.%). A single pass friction stir processing was done using a tool rotational speed of 1000 rpm, travel speed of 40 mm/min and an axial force of 10 kN. Metallurgical characterization of the Cu/B{sub 4}C surface composites was carried out using optical microscope and scanning electron microscope. The sliding wear behavior was evaluated using a pin-on-disk apparatus. Results indicated that the B{sub 4}C particles significantly influenced the area, dispersion, grain size, microhardness and sliding wear behavior of the Cu/B{sub 4}C surface composites. When the volume fraction of B{sub 4}C was increased, the wear mode changed from microcutting to abrasive wear and wear debris was found to be finer. Highlights: • Fabrication of Cu/B{sub 4}C surface composite by friction stir processing • Analyzing the effect of B{sub 4}C particles on the properties of Cu/B4C surface composite • Increased volume fraction of B{sub 4}C particles reduced the area of surface composite. • Increased volume fraction of B{sub 4}C particles enhanced the microhardness and wear rate. • B{sub 4}C particles altered the wear mode from microcutting to abrasive.

  18. Preparation of electrodes on cfrp composites with low contact resistance comprising laser-based surface pre-treatment

    KAUST Repository

    Almuhammadi, Khaled Hamdan

    2016-12-29

    Various examples are provided related to the preparation of electrodes on carbon fiber reinforced polymer (CFRP) composites with low contact resistance. Laser-based surface preparation can be used for bonding to CFRP composites. In one example, a method includes preparing a pretreated target area on a CFRP composite surface using laser pulsed irradiation and bonding an electrode to exposed fibers in the pretreated target area. The surface preparation can allow the electrode to have a low contact resistance with the CFRP composite.

  19. Seasonal Variations in Surface Metabolite Composition of Fucus vesiculosus and Fucus serratus from the Baltic Sea.

    Directory of Open Access Journals (Sweden)

    Esther Rickert

    Full Text Available Perennial macroalgae within the genus Fucus are known to exude metabolites through their outer thallus surface. Some of these metabolites have pro- and/or antifouling properties. Seasonal fluctuations of natural fouling pressure and chemical fouling control strength against micro- and macrofoulers have previously been observed in Fucus, suggesting that control strength varies with threat. To date, a study on the seasonal composition of surface associated metabolites, responsible for much of the fouling control, has not been done. We sampled individuals of the two co-occurring species F. vesiculosus and F. serratus at monthly intervals (six per species and month during a one-year field study. We analysed the chemical composition of surface associated metabolites of both Fucus species by means of gas chromatography-mass spectrometry (GC-MS to describe temporal patterns in chemical surface composition. Additionally, we correlated abiotic and biotic parameters recorded monthly within the sampled habitat with the variation in the chemical surface landscape of Fucus. Our study revealed that the chemical surface composition of both Fucus species exhibits substantial seasonal differences between spring/summer and autumn/winter months. Light and temperature explained most of the seasonal variability in surface metabolite composition of both Fucus species. A strong summerly up-regulation of eighteen saccharides and two hydroxy acids in F. vesiculosus as well as of four fatty acids and two saccharides in F. serratus was observed. We discuss how these up-regulated molecules may have a complex effect on associated microfoulers, both promoting or decreasing fouling depending on metabolite and bacterial identity. These seasonal shifts in the surface metabolome seem to exert a compound control of density and composition of the Fucus associated biofilm.

  20. Surface roughness of novel resin composites polished with one-step systems.

    Science.gov (United States)

    Ergücü, Z; Türkün, L S

    2007-01-01

    This study: 1) analyzed the surface roughness of five novel resin composites that contain nanoparticles after polishing with three different one-step systems and 2) evaluated the effectiveness of these polishers and their possible surface damage using scanning electron microscope (SEM) analysis. The resin composites evaluated in this study include CeramX, Filtek Supreme XT, Grandio, Premise and Tetric EvoCeram. A total of 100 discs (20/resin composites, 10 x 2 mm) were fabricated. Five specimens/resin composites cured under Mylar strips served as the control. The samples were polished for 30 seconds with PoGo, OptraPol and One Gloss discs at 15,000 rpm using a slow speed handpiece. The surfaces were tested for roughness (Ra) with a surface roughness tester and examined with SEM. One-way ANOVA was used for statistical analysis (p = 0.05). For all the composites tested, differences between the polishing systems were found to be significant (p One Gloss applications. For Grandio, Mylar and PoGo created equally smooth surfaces, while OptraPol and One Gloss produced equally rougher surfaces. Tetric EvoCeram exhibited the roughest surface with OptraPol, while no significant differences were found between Premise and CeramX. According to SEM images, OptraPol and One Gloss scratched and plucked the particles away from the surface, while PoGo created a uniform finish, although the roughness values were not the same for each composite. Effectiveness of the polishers seems to be material dependent.

  1. Multifunctional polymer nano-composite based superhydrophobic surface

    Science.gov (United States)

    Maitra, Tanmoy; Asthana, Ashish; Buchel, Robert; Tiwari, Manish K.; Poulikakos, Dimos

    2014-11-01

    Superhydrophobic surfaces become desirable in plethora of applications in engineering fields, automobile industry, construction industries to name a few. Typical fabrication of superhydrophobic surface consists of two steps: first is to create rough morphology on the substrate of interest, followed by coating of low energy molecules. However, typical exception of the above fabrication technique would be direct coating of functional polymer nanocomposites on substrate where superhydrophobicity is needed. Also in this case, the use of different nanoparticles in the polymer matrix can be exploited to impart multi-functional properties to the superhydrophobic coatings. Herein, different carbon nanoparticles like graphene nanoplatelets (GNP), carbon nanotubes (CNT) and carbon black (CB) are used in fluropolymer matrix to prepare superhydrophobic coatings. The multi-functional properties of coatings are enhanced by combining two different carbon fillers in the matrix. The aforementioned superhydrophobic coatings have shown high electrical conductivity and excellent droplet meniscus impalement resistance. Simultaneous superhydrophobic and oleophillic character of the above coating is used to separate mineral oil and water through filtration of their mixture. Swiss National Science Foundation (SNF) Grant 200021_135479.

  2. EVALUATION MODEL FOR PAVEMENT SURFACE DISTRESS ON 3D POINT CLOUDS FROM MOBILE MAPPING SYSTEM

    Directory of Open Access Journals (Sweden)

    K. Aoki

    2012-07-01

    Full Text Available This paper proposes a methodology to evaluate the pavement surface distress for maintenance planning of road pavement using 3D point clouds from Mobile Mapping System (MMS. The issue on maintenance planning of road pavement requires scheduled rehabilitation activities for damaged pavement sections to keep high level of services. The importance of this performance-based infrastructure asset management on actual inspection data is globally recognized. Inspection methodology of road pavement surface, a semi-automatic measurement system utilizing inspection vehicles for measuring surface deterioration indexes, such as cracking, rutting and IRI, have already been introduced and capable of continuously archiving the pavement performance data. However, any scheduled inspection using automatic measurement vehicle needs much cost according to the instruments’ specification or inspection interval. Therefore, implementation of road maintenance work, especially for the local government, is difficult considering costeffectiveness. Based on this background, in this research, the methodologies for a simplified evaluation for pavement surface and assessment of damaged pavement section are proposed using 3D point clouds data to build urban 3D modelling. The simplified evaluation results of road surface were able to provide useful information for road administrator to find out the pavement section for a detailed examination and for an immediate repair work. In particular, the regularity of enumeration of 3D point clouds was evaluated using Chow-test and F-test model by extracting the section where the structural change of a coordinate value was remarkably achieved. Finally, the validity of the current methodology was investigated by conducting a case study dealing with the actual inspection data of the local roads.

  3. Mapping of local argon impingement on a virtual surface: an insight for gas injection during FEBID

    Energy Technology Data Exchange (ETDEWEB)

    Wanzenboeck, H.D.; Hochleitner, G.; Mika, J.; Shawrav, M.M.; Gavagnin, M.; Bertagnolli, E. [Vienna University of Technology, Institute for Solid State Electronics, Vienna (Austria)

    2014-12-15

    During the last decades, focused electron beam induced deposition (FEBID) has become a successful approach for direct-write fabrication of nanodevices. Such a deposition technique relies on the precursor supply to the sample surface which is typically accomplished by a gas injection system using a tube-shaped injector nozzle. This precursor injection strategy implies a position-dependent concentration gradient on the surface, which affects the geometry and chemistry of the final nanodeposit. Although simulations already proposed the local distribution of nozzle-borne gas molecules impinging on the surface, this isolated step in the FEBID process has never been experimentally measured yet. This work experimentally investigates the local distribution of impinging gas molecules on the sample plane, isolating the direct impingement component from surface diffusion or precursor depletion by deposition. The experimental setup used in this work maps and quantifies the local impinging rate of argon gas over the sample plane. This setup simulates the identical conditions for a precursor molecule during FEBID. Argon gas was locally collected with a sniffer tube, which is directly connected to a residual gas analyzer for quantification. The measured distribution of impinging gas molecules showed a strong position dependence. Indeed, a 300-μm shift of the deposition area to a position further away from the impingement center spot resulted in a 50 % decrease in the precursor impinging rate on the surface area. With the same parameters, the precursor distribution was also simulated by a Monte Carlo software by Friedli and Utke and showed a good correlation between the empirical and the simulated precursor distribution. The results hereby presented underline the importance of controlling the local precursor flux conditions in order to obtain reproducible and comparable deposition results in FEBID. (orig.)

  4. Mapping of local argon impingement on a virtual surface: an insight for gas injection during FEBID

    International Nuclear Information System (INIS)

    Wanzenboeck, H.D.; Hochleitner, G.; Mika, J.; Shawrav, M.M.; Gavagnin, M.; Bertagnolli, E.

    2014-01-01

    During the last decades, focused electron beam induced deposition (FEBID) has become a successful approach for direct-write fabrication of nanodevices. Such a deposition technique relies on the precursor supply to the sample surface which is typically accomplished by a gas injection system using a tube-shaped injector nozzle. This precursor injection strategy implies a position-dependent concentration gradient on the surface, which affects the geometry and chemistry of the final nanodeposit. Although simulations already proposed the local distribution of nozzle-borne gas molecules impinging on the surface, this isolated step in the FEBID process has never been experimentally measured yet. This work experimentally investigates the local distribution of impinging gas molecules on the sample plane, isolating the direct impingement component from surface diffusion or precursor depletion by deposition. The experimental setup used in this work maps and quantifies the local impinging rate of argon gas over the sample plane. This setup simulates the identical conditions for a precursor molecule during FEBID. Argon gas was locally collected with a sniffer tube, which is directly connected to a residual gas analyzer for quantification. The measured distribution of impinging gas molecules showed a strong position dependence. Indeed, a 300-μm shift of the deposition area to a position further away from the impingement center spot resulted in a 50 % decrease in the precursor impinging rate on the surface area. With the same parameters, the precursor distribution was also simulated by a Monte Carlo software by Friedli and Utke and showed a good correlation between the empirical and the simulated precursor distribution. The results hereby presented underline the importance of controlling the local precursor flux conditions in order to obtain reproducible and comparable deposition results in FEBID. (orig.)

  5. Mapping of local argon impingement on a virtual surface: an insight for gas injection during FEBID

    Science.gov (United States)

    Wanzenboeck, H. D.; Hochleitner, G.; Mika, J.; Shawrav, M. M.; Gavagnin, M.; Bertagnolli, E.

    2014-12-01

    During the last decades, focused electron beam induced deposition (FEBID) has become a successful approach for direct-write fabrication of nanodevices. Such a deposition technique relies on the precursor supply to the sample surface which is typically accomplished by a gas injection system using a tube-shaped injector nozzle. This precursor injection strategy implies a position-dependent concentration gradient on the surface, which affects the geometry and chemistry of the final nanodeposit. Although simulations already proposed the local distribution of nozzle-borne gas molecules impinging on the surface, this isolated step in the FEBID process has never been experimentally measured yet. This work experimentally investigates the local distribution of impinging gas molecules on the sample plane, isolating the direct impingement component from surface diffusion or precursor depletion by deposition. The experimental setup used in this work maps and quantifies the local impinging rate of argon gas over the sample plane. This setup simulates the identical conditions for a precursor molecule during FEBID. Argon gas was locally collected with a sniffer tube, which is directly connected to a residual gas analyzer for quantification. The measured distribution of impinging gas molecules showed a strong position dependence. Indeed, a 300-µm shift of the deposition area to a position further away from the impingement center spot resulted in a 50 % decrease in the precursor impinging rate on the surface area. With the same parameters, the precursor distribution was also simulated by a Monte Carlo software by Friedli and Utke and showed a good correlation between the empirical and the simulated precursor distribution. The results hereby presented underline the importance of controlling the local precursor flux conditions in order to obtain reproducible and comparable deposition results in FEBID.

  6. Fracture surface analysis on nano-SiO{sub 2}/epoxy composite

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Rongguo [Institute of Fundamental Mechanics and Material Engineering, Xiangtan University, Hunan 411105 (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Hunan 411105 (China)], E-mail: zhaorongguo@xtu.edu.cn; Luo Wenbo [Institute of Fundamental Mechanics and Material Engineering, Xiangtan University, Hunan 411105 (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Hunan 411105 (China)

    2008-06-15

    Fracture surface morphologies of nano-SiO{sub 2}/epoxy composite with different weight percentage of SiO{sub 2} are investigated using scanning electron microscopy. Two types of curing agent, dimethylbenzanthracene (DMBA) and methyltetrahydrophthalic anhydride (MeTHPA), are individually used for preparing the composites. It is found that the fracture surface morphology of the composite cured by DMBA shows as radial striations, which suggests a rapid brittle fracture mode, while the fracture surface morphology of the composite cured by MeTHPA shows as regularly spaced 'rib' markings, which indicates a stick-slip motion during the fracture process. Furthermore, the uniaxial tensile behavior under constant loading rate and ambient temperature are investigated. It is shown that the elastic modulus of the composite cured by DMBA firstly increases, and then decreases with the mass fraction of nano-SiO{sub 2} particles, but the elongation of the composite cured by MeTHPA is reversed with increasing fraction of nano-SiO{sub 2} particles. For nano-SiO{sub 2}/epoxy composite cured with MeTHPA that possesses a suitable fraction of nano-SiO{sub 2}, an excellent synthetic mechanical property on elastic modulus and elongation is obtained.

  7. Correlation between three-dimentional surface topography and color stability of different nanofilled composites.

    Science.gov (United States)

    Öztürk, Elif; Güder, Gizem

    2015-01-01

    The aim of this study was to evaluate the 3-dimensional (3D) surface topography and color stability of four different resin composites after immersion in different soft-beverages. One hundred sixty disk-shaped specimens (diameter: 10 mm, and thickness: 2 mm) were made from four different resin composites (i.e., Filtek Z550, Tetric N-Ceram, Clearfil Majesty Esthetic, and Cavex Quadrant Universal LC). Each specimen was cured under mylar strips for 20 sec for both top and bottom surfaces. All of the specimens were stored in distilled water for 24 h at 37°C. Surface measurements were carried out using a noncontact 3D-optical-profilometer in terms of surface topography (Ra values). Color measurements of each specimen were performed with Vita Easy Shade system. All the measurements were performed at baseline and after 30 days of immersion in the selected soft-beverages (Redbull, Coca-Cola and Dimes-Lemonade). Control groups were stored in distilled water during the study. Ra values and color changes (ΔE values) of the groups were recorded. The data were statistically analyzed using a one way ANOVA and Tukey's post-hoc tests (SPSS 18.0). The tested soft-beverages in the present study caused color changes at a 30-day evaluation period for the tested resin composites (p composites was not influenced by the tested soft-beverages (p > 0.05). There was no significant interaction between the composite and beverage type on the Ra values of the resin composites (p > 0.05). No correlation was found between color stability and 3D surface topography of the resin composites. Color stability of resin composites may be affected by soft beverages. © Wiley Periodicals, Inc.

  8. Mapping the surface of Escherichia coli peptide deformylase by NMR with organic solvents.

    Science.gov (United States)

    Byerly, Douglas W; McElroy, Craig A; Foster, Mark P

    2002-07-01

    Identifying potential ligand binding sites on a protein surface is an important first step for targeted structure-based drug discovery. While performing control experiments with Escherichia coli peptide deformylase (PDF), we noted that the organic solvents used to solubilize some ligands perturbed many of the same resonances in PDF as the small molecule inhibitors. To further explore this observation, we recorded (15)N HSQC spectra of E. coli peptide deformylase (PDF) in the presence of trace quantities of several simple organic solvents (acetone, DMSO, ethanol, isopropanol) and identified their sites of interaction from local perturbation of amide chemical shifts. Analysis of the protein surface structure revealed that the ligand-induced shift perturbations map to the active site and one additional surface pocket. The correlation between sites of solvent and inhibitor binding highlights the utility of organic solvents to rapidly and effectively validate and characterize binding sites on proteins prior to designing a drug discovery screen. Further, the solvent-induced perturbations have implications for the use of organic solvents to dissolve candidate ligands in NMR-based screens.

  9. Effect of surface modification on carbon fiber and its reinforced phenolic matrix composite

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Hua [Key Laboratory for Liquid phase chemical oxidation Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061 (China); Carbon Fibre Engineering Research Center, Faculty of Materials Science, Shandong University, Jinan 250061 (China); Wang Chengguo, E-mail: sduwangchg@gmail.com [Carbon Fibre Engineering Research Center, Faculty of Materials Science, Shandong University, Jinan 250061 (China); Zhang Shan; Lin Xue [Carbon Fibre Engineering Research Center, Faculty of Materials Science, Shandong University, Jinan 250061 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer We used very simple and effective modification method to treat PAN-based carbon fiber by liquid oxidation and coupling agent. Black-Right-Pointing-Pointer Carbon fiber surface functional groups were analyzed by LRS and XPS. Black-Right-Pointing-Pointer Proper treatment of carbon fiber can prove an effective way to increase composite's performance. Black-Right-Pointing-Pointer Carbon fiber surface modifications by oxidation and APS could strengthen fiber activity and enlarge surface area as well as its roughness. - Abstract: In this work, polyacrylonitrile (PAN)-based carbon fiber were chemically modified with H{sub 2}SO{sub 4}, KClO{sub 3} and silane coupling agent ({gamma}-aminopropyltriethoxysilane, APS), and carbon fiber reinforced phenolic matrix composites were prepared. The structural and surface characteristics of the carbon fiber were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), laser Raman scattering (LRS) and Fourier transform infrared spectroscopy (FTIR). Single fiber mechanical properties, specific surface area, composite impact properties and interfacial shear strength (ILSS) were researched to indicate the effects of surface modification on fibers and the interaction between modified fiber surface and phenolic matrix. The results showed that carbon fiber surface modification by oxidation and APS can strengthen fiber surface chemical activity and enlarge the fiber surface area as well as its roughness. When carbon fiber (CF) is oxidized treatment, the oxygen content as well as the O/C ratio will be obviously increased. Oxygen functional groups increase with oxidation time increasing. Carbon fiber treated with APS will make C-O-R content increase and O-C=O content decrease due to surface reaction. Proper treatment of carbon fiber with acid and silane coupling agent prove an effective way to increase the interfacial adhesion and improve the mechanical and outdoor

  10. Effect of surface modification on carbon fiber and its reinforced phenolic matrix composite

    International Nuclear Information System (INIS)

    Yuan Hua; Wang Chengguo; Zhang Shan; Lin Xue

    2012-01-01

    Highlights: ► We used very simple and effective modification method to treat PAN-based carbon fiber by liquid oxidation and coupling agent. ► Carbon fiber surface functional groups were analyzed by LRS and XPS. ► Proper treatment of carbon fiber can prove an effective way to increase composite's performance. ► Carbon fiber surface modifications by oxidation and APS could strengthen fiber activity and enlarge surface area as well as its roughness. - Abstract: In this work, polyacrylonitrile (PAN)-based carbon fiber were chemically modified with H 2 SO 4 , KClO 3 and silane coupling agent (γ-aminopropyltriethoxysilane, APS), and carbon fiber reinforced phenolic matrix composites were prepared. The structural and surface characteristics of the carbon fiber were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), laser Raman scattering (LRS) and Fourier transform infrared spectroscopy (FTIR). Single fiber mechanical properties, specific surface area, composite impact properties and interfacial shear strength (ILSS) were researched to indicate the effects of surface modification on fibers and the interaction between modified fiber surface and phenolic matrix. The results showed that carbon fiber surface modification by oxidation and APS can strengthen fiber surface chemical activity and enlarge the fiber surface area as well as its roughness. When carbon fiber (CF) is oxidized treatment, the oxygen content as well as the O/C ratio will be obviously increased. Oxygen functional groups increase with oxidation time increasing. Carbon fiber treated with APS will make C-O-R content increase and O-C=O content decrease due to surface reaction. Proper treatment of carbon fiber with acid and silane coupling agent prove an effective way to increase the interfacial adhesion and improve the mechanical and outdoor performance of the resulting fiber/resin composites.

  11. IRAS surface brightness maps of visible reflection nebulae: evidence for non-equilibrium infrared emission

    International Nuclear Information System (INIS)

    Castelaz, M.W.; Werner, M.W.; Sellgren, K.

    1986-01-01

    Surface brightness maps at 12, 25, 60, and 100 microns of 16 visible reflection nebulae were extracted from the Infrared Astronomy Satellite (IRAS) database. The maps were produced by coadding IRAS survey scans over areas centered on the illuminating stars, and have spatial resolutions of 0.9' x 4' at 12 and 25 microns, 1.8' x 4.5' at 60 microns, and 3.6' x 5' at 100 microns. Extended emission in the four IRAS bandpasses was detected in fourteen of the reflection nebulae. The IRAS data were used to measure the flux of the infrared emission associated with each source. The energy distributions show that the 12 micron flux is greater than the 25 micron flux in 11 of the nebulae, and the peak flux occurs in the 60 or 100 micron bandpass in all 16 nebular. The 60 and 100 micron flux can be approximated by blackbodies with temperatures between 30 and 50 K, consistent with temperatures expected from extrapolation of greybody fits to the 60 and 100 micron data. The excess 12 and 25 micron emission is attributed to a nonequilibrium process such as emission from thermal fluctuations of very small grains excited by single ultraviolet photons, or emission from polycyclic aromatic hydrocarbons (PAHs) excited by ultraviolet radiation. The common features of the energy distributions of the 16 reflection nebulae, also seen in the reflection nebulae associated with the Pleiades, suggest that PAHs or very small grains may be found in most reflection nebulae

  12. The effect of various dentifrices on surface roughness and gloss of resin composites.

    Science.gov (United States)

    da Costa, Juliana; Adams-Belusko, Anne; Riley, Kelly; Ferracane, Jack L

    2010-01-01

    The purpose of this study was to evaluate the effect of different levels of abrasiveness (RDA) of dentifrices on the gloss and surface roughness of resin composites after toothbrushing. Sixty disk-shaped composite specimens (D=10.0mm, 2-mm thick, n=15 per material) were made of: microfill (Durafill), nanofill (Filtek Supreme), minifill hybrid (Filtek 250), and nanohybrid (Premise). One side of each specimen was finished with a carbide bur and polished with Enhance and Pogo. Five specimens of each composite were randomly assigned to one of the dentifrices, Colgate Total (CT; RDA 70), Colgate baking soda & peroxide whitening (CBS; RDA 145), and Colgate tartar control & whitening (CTW; RDA 200). Surface gloss was measured with a glossmeter and surface roughness with a profilometer before and after toothbrushing with a 1:2 slurry (dentifrice/deionised water) at 5760 strokes in a brushing machine (approximately 1Hz). Results were analyzed by three-way ANOVA/Tukey's (pgloss and increase in surface roughness after brushing with all dentifrices. There was no significant difference in gloss when Durafill was brushed with any dentifrice; the other composites showed less gloss reduction when brushed with CT. Durafill, Supreme and Premise did not show significantly different surface roughness results and CBS and CTW did not produce significantly different results. Dentifrices of lower abrasivity promote less reduction in gloss and surface roughness for composites of different particle sizes after brushing. Composites containing smaller average fillers showed less reduction in gloss and less increase in surface roughness than ones with larger fillers. Published by Elsevier Ltd.

  13. Design of tunable surface mode waveguide based on photonic crystal composite structure using organic liquid*

    International Nuclear Information System (INIS)

    Zhang Lan-Lan; Liu Wei; Li Ping; Yang Xi; Cao Xu

    2017-01-01

    With the method of replacing the surface layer of photonic crystal with tubes, a novel photonic crystal composite structure used as a tunable surface mode waveguide is designed. The tubes support tunable surface states. The tunable propagation capabilities of the structure are investigated by using the finite-difference time-domain. Simulation results show that the beam transmission distributions of the composite structure are sensitive to the frequency range of incident light and the surface morphology which can be modified by filling the tubes with different organic liquids. By adjusting the filler in tubes, the T-shaped, Y-shaped, and L-shaped propagations can be realized. The property can be applied to the tunable surface mode waveguide. Compared with a traditional single function photonic crystal waveguide, our designed structure not only has a small size, but also is a tunable device. (paper)

  14. Relation between surface properties of thin composite films and osteoblast behaviour in vitro

    International Nuclear Information System (INIS)

    Polak, B; Olkowski, R; Kobiela, T; Lewandowska-Szumiel, M; Fabianowski, W

    2007-01-01

    Si supports for cell culture were modified using poly(acrylic acid) (PAA) and bentonite in order to obtain 'sandwich'-like structures. A layer of PAA cast from water solution was followed with a bentonite layer also cast from water dispersion, then another PAA layer and so on up to six layers. The prepared surfaces had different physical and chemical properties like thickness, topography and elasticity. Chemical composition was characterized by Raman spectroscopy. The elastic properties and topography of modified sandwich-like surfaces were evaluated using nanoindentation and atomic force microscopy measurements. In the next step bone cells were cultured on such modified surfaces composed of one to six layers. The influence of the substrate surface properties on the growth and behaviour of human bone derived cells (HBDC) was studied. The influence of surface topography, elasticity and chemical composition on cells is discussed

  15. Optimization of composite flour biscuits by mixture response surface methodology.

    Science.gov (United States)

    Okpala, Laura C; Okoli, Eric C

    2013-08-01

    Biscuits were produced from blends of pigeon pea, sorghum and cocoyam flours. The study was carried out using mixture response surface methodology as the optimization technique. Using the simplex centroid design, 10 formulations were obtained. Protein and sensory quality of the biscuits were analyzed. The sensory attributes studied were appearance, taste, texture, crispness and general acceptability, while the protein quality indices were biological value and net protein utilization. The results showed that while the addition of pigeon pea improved the protein quality, its addition resulted in reduced sensory ratings for all the sensory attributes with the exception of appearance. Some of the biscuits had sensory ratings, which were not significantly different (p > 0.05) from biscuits made with wheat. Rat feeding experiments indicated that the biological value and net protein utilization values obtained for most of the biscuits were above minimum recommended values. Optimization suggested biscuits containing 75.30% sorghum, 0% pigeon pea and 24.70% cocoyam flours as the best proportion of these components. This sample received good scores for the sensory attributes.

  16. Surface composition and topography of the graphite limiter in ASDEX

    International Nuclear Information System (INIS)

    Behrisch, R.; Boergesen, P.; Ehrenberg, J.; Scherzer, B.M.U.; Sawicka, B.D.; Sawicki, J.A.

    1984-01-01

    After having been in use during about 150 discharges the graphite limiter of the ASDEX tokamak was removed and analyzed by means of SEM, EIXE, PIXE, RBS and Moessbauer Spectroscopy. The surface was seen to be covered by a nonuniform layer of 10 16 -10 18 metal at/cm 2 , primarily in the form of droplets with diameters up to a few μm. Simulation experiments suggest that the formation of these droplets is caused by heating. The relative metal concentrations in the droplets are close to those for stainless steel. The Moessbauer spectroscopy analysis indicates, however, that the major part of the metal is present in carbide phases, most probably (Fe, Cr, Ni) 3 C. On parts of the limiter the metal coverage shows a sharp maximum at the points nearest the main plasma, flanked by two minima. The minimum on the ion drift side is much broader than the one on the electron drift side. However, these features are not common to all parts of the limiter. (orig.)

  17. Effects of phosphourus addition on the physical properties and surface condition of tungsten-copper composites

    International Nuclear Information System (INIS)

    Akiyoshi, N.; Nakada, K.; Nakayama, M.; Kohda, K.

    2001-01-01

    Tungsten-copper composites containing a small amount of phosphorus prepared using conventional P/M method. Cu 3 P powder was used as phosphorous source. The effects of phosphorus addition on the physical properties and the surface condition were investigated and the existing form of phosphorus was specified on the tungsten-copper composites The results are summarized as follows. The tungsten-copper composite containing 10 % copper, for example, demonstrated optimum thermal conductivity at the phosphorus addition of 0.02 %. The density of the composites was almost 100 % and the surface of the sintered body was flat and smooth after sintering at a temperature between 1100 and 1150 o C. It was shown that phosphorus exists as Co 2 P. (author)

  18. Composites of Graphene Nanoribbon Stacks and Epoxy for Joule Heating and Deicing of Surfaces.

    Science.gov (United States)

    Raji, Abdul-Rahman O; Varadhachary, Tanvi; Nan, Kewang; Wang, Tuo; Lin, Jian; Ji, Yongsung; Genorio, Bostjan; Zhu, Yu; Kittrell, Carter; Tour, James M

    2016-02-10

    A conductive composite of graphene nanoribbon (GNR) stacks and epoxy is fabricated. The epoxy is filled with the GNR stacks, which serve as a conductive additive. The GNR stacks are on average 30 nm thick, 250 nm wide, and 30 μm long. The GNR-filled epoxy composite exhibits a conductivity >100 S/m at 5 wt % GNR content. This permits application of the GNR-epoxy composite for deicing of surfaces through Joule (voltage-induced) heating generated by the voltage across the composite. A power density of 0.5 W/cm(2) was delivered to remove ∼1 cm-thick (14 g) monolith of ice from a static helicopter rotor blade surface in a -20 °C environment.

  19. Effects of hydrogen peroxide bleaching strips on tooth surface color, surface microhardness, surface and subsurface ultrastructure, and microchemical (Raman spectroscopic) composition.

    Science.gov (United States)

    Duschner, Heinz; Götz, Hermann; White, Donald J; Kozak, Kathleen M; Zoladz, James R

    2006-01-01

    This study examined the effects of hydrogen peroxide tooth bleaching strips on the surface hardness and morphology of enamel and the ultrastructure and chemical composition of enamel and dentin in vitro. Sound human molars were ground and polished to prepare a uniform substrate for bleaching treatments. A cycling treatment methodology was employed which alternated ex vivo human salivary exposures with bleaching treatments under conditions of controlled temperature and durations of treatment. Bleaching treatments included commercial Crest Whitestrips bleaching strips, which utilize hydrogen peroxide in a gel as the in situ bleaching source at 6.0 and 6.5% concentrations of H2O2. Control treatments included an untreated group. Crest Whitestrips bleaching included treatment exposures simulating 2x the recommended clinical exposures (28 hours bleaching). Surface color measurements were taken prior to and following bleaching to ensure tooth bleaching activity. The effects of bleach on physical properties of enamel were assessed with microhardness measures. Ultrastructural effects were classified by surface and subsurface confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) techniques. In addition, the effects of bleaching on tooth microchemical composition was studied in different tooth regions by coincident assessment of Raman spectroscopic signature. Color assessments confirmed significant ex vivo tooth bleaching by Whitestrips. Surface microhardness and SEM measures revealed no deleterious effects on the enamel surfaces. CLSM micromorphological assessments supported the safety of hydrogen peroxide bleaching strips both on surface and subsurface enamel, DEJ, and dentin ultrastructure. Raman spectroscopy analysis demonstrated no obvious effects of bleaching treatments on the microchemical composition of enamel and dentin. These results confirm that tooth bleaching with hydrogen peroxide whitening strips does not produce changes in surface

  20. ST-T isointegral analysis of exercise stress body surface mapping for identifying ischemic areas in patients with angina pectoris

    International Nuclear Information System (INIS)

    Nakajima, T.; Kawakubo, K.; Toda, I.; Mashima, S.; Ohtake, T.; Iio, M.; Sugimoto, T.

    1988-01-01

    ST-T isointegral analysis of body surface mapping was used in an attempt to localize ischemic areas on exercise tests. In 28 patients with angina pectoris and 10 healthy subjects, body surface potential was recorded with 87 leads, and ST isopotential and ST-T isointegral maps were constructed. In all 10 healthy subjects, the basic pattern of the ST-T isointegral map showed no significant change after exercise. In 23 of 28 patients with angina pectoris (82%), alterations in the ST-T isointegral map after exercise were observed. They were divided into four types (anterior, inferoposterior, lateral, and global) according to the distribution of negative values, which were well correlated with the extent of ischemic area determined by thallium myocardial scintigraphy and coronary angiography. The postexercise ST-T isointegral map was normalized after administration of nitroglycerin in four of five patients. In five patients (18%) who did not show abnormalities on the postexercise ST-T isointegral map, the magnitude of maximal ST depression was significantly smaller than that observed in the other 23 patients with angina pectoris (0.14 vs 0.23 mV on the average, p less than 0.05). It was concluded that the exercise test with ST-T isointegral mapping is a new method for noninvasive detection of location and severity of ischemic regions

  1. Computerized mappings of the cerebral cortex: a multiresolution flattening method and a surface-based coordinate system

    Science.gov (United States)

    Drury, H. A.; Van Essen, D. C.; Anderson, C. H.; Lee, C. W.; Coogan, T. A.; Lewis, J. W.

    1996-01-01

    We present a new method for generating two-dimensional maps of the cerebral cortex. Our computerized, two-stage flattening method takes as its input any well-defined representation of a surface within the three-dimensional cortex. The first stage rapidly converts this surface to a topologically correct two-dimensional map, without regard for the amount of distortion introduced. The second stage reduces distortions using a multiresolution strategy that makes gross shape changes on a coarsely sampled map and further shape refinements on progressively finer resolution maps. We demonstrate the utility of this approach by creating flat maps of the entire cerebral cortex in the macaque monkey and by displaying various types of experimental data on such maps. We also introduce a surface-based coordinate system that has advantages over conventional stereotaxic coordinates and is relevant to studies of cortical organization in humans as well as non-human primates. Together, these methods provide an improved basis for quantitative studies of individual variability in cortical organization.

  2. Apparent Surface Free Energy of Polymer/Paper Composite Material Treated by Air Plasma

    Directory of Open Access Journals (Sweden)

    Konrad Terpiłowski

    2017-01-01

    Full Text Available Surface plasma treatment consists in changes of surface properties without changing internal properties. In this paper composite polymer/paper material is used for production of packaging in cosmetic industry. There are problems with bonding this material at the time of packaging production due to its properties. Composite surface was treated by air plasma for 1, 10, 20, and 30 s. The advancing and receding contact angles of water, formamide, and diiodomethane were measured using both treated and untreated samples. Apparent surface free energy was estimated using the hysteresis (CAH and Van Oss, Good, Chaudhury approaches (LWAB. Surface roughness was investigated using optical profilometry and identification of after plasma treatment emerging chemical groups was made by means of the XPS (X-ray photoelectron spectroscopy technique. After plasma treatment the values of contact angles decreased which is particularly evident for polar liquids. Apparent surface free energy increased compared to that of untreated samples. Changes of energy value are due to the electron-donor parameter of energy. This parameter increases as a result of adding polar groups at the time of surface plasma activation. Changes of surface properties are combination of increase of polar chemical functional groups, increase on the surface, and surface roughness increase.

  3. Lunar atmosphere. How surface composition and meteoroid impacts mediate sodium and potassium in the lunar exosphere.

    Science.gov (United States)

    Colaprete, A; Sarantos, M; Wooden, D H; Stubbs, T J; Cook, A M; Shirley, M

    2016-01-15

    Despite being trace constituents of the lunar exosphere, sodium and potassium are the most readily observed species due to their bright line emission. Measurements of these species by the Ultraviolet and Visible Spectrometer (UVS) on the Lunar Atmosphere and Dust Environment Explorer (LADEE) have revealed unambiguous temporal and spatial variations indicative of a strong role for meteoroid bombardment and surface composition in determining the composition and local time dependence of the Moon's exosphere. Observations show distinct lunar day (monthly) cycles for both species as well as an annual cycle for sodium. The first continuous measurements for potassium show a more repeatable variation across lunations and an enhancement over KREEP (Potassium Rare Earth Elements and Phosphorus) surface regions, revealing a strong dependence on surface composition. Copyright © 2016, American Association for the Advancement of Science.

  4. Fabrication of mesoporous and high specific surface area lanthanum carbide-carbon nanotube composites

    International Nuclear Information System (INIS)

    Biasetto, L.; Carturan, S.; Maggioni, G.; Zanonato, P.; Bernardo, P. Di; Colombo, P.; Andrighetto, A.; Prete, G.

    2009-01-01

    Mesoporous lanthanum carbide-carbon nanotube composites were produced by means of carbothermal reaction of lanthanum oxide, graphite and multi-walled carbon nanotube mixtures under high vacuum. Residual gas analysis revealed the higher reactivity of lanthanum oxide towards carbon nanotubes compared to graphite. After sintering, the composites revealed a specific surface area increasing with the amount of carbon nanotubes introduced. The meso-porosity of carbon nanotubes was maintained after thermal treatment.

  5. Effect of a New Surface Treatment Solution on the Bond Strength of Composite to Enamel

    Science.gov (United States)

    2016-06-01

    Bond Strength of Composite to Enamel " is appropriately acknowledged and, beyond brief excerpts, is with the permission of the copyright owner...Solution on the Bond Strength of Composite to Enamel ABSTRACT Clean & Boost (Apex Dental Materials) is a novel surface treatment solution...designed to be used in place of phosphoric acid to increase the bond strength of self-etch adhesives to enamel and more effectively remove contaminants

  6. Effect of different polishing systems on the surface roughness of nano-hybrid composites

    OpenAIRE

    Brijesh Patel; Naveen Chhabra; Disha Jain

    2016-01-01

    Objective: The study aimed to investigate the influence of different polishing systems on the surface roughness of nano-hybrid composite resins. Background: Different shapes of polishing systems are available according to the site of work. To minimize variability, a new system with single shape is developed that can be utilized in both anterior as well as posterior teeth. Materials and Methods: Seventy composite discs were fabricated using Teflon well (10 mm × 3 mm). Two main group of...

  7. [Surface roughness and gloss of novel flowable composites after polishing and simulated brushing wear].

    Science.gov (United States)

    Wang, R L; Yuan, C Y; Pan, Y X; Tian, F C; Wang, Z H; Wang, X Y

    2017-04-09

    Objective: To investigate surface properties of novel flowable composites after polishing and simulated brushing wear, compared to their pasty counterpart. Methods: Composites employed in this study were: three flowable composites (A1: Clearfil Majesty ES Flow; B1: Beautifil Flow Plus F00; C1: Filtek Bulk Fill) and three paste composites (A2: Clearfil Majesty; B2: Beautifil; C2: Filtek Z350. Eleven disk-shaped specimens were made for each material. The specimens were cured, then subjected to sandpaper finishing for 20 s, one-step polishing for 30 s, finally subjected to simulated brushing for 10 000 cycles. Surface roughness and glossiness were measured before finishing, after finishing, after polishing, after 5 000 brushing cycles and after 10 000 brushing cycles, respectively. Data obtained were analyzed using two-way ANOVA method. Scanning electron microscope was employed to examine the microscopic appearance of each material. Results: Surface roughness (0.11~0.22 μm) and glossiness (74.25~86.48 GU) of each material were similar after one-step polishing. After brushing simulation, roughness increased significantly and glossiness decreased significantly for each material ( Pgloss ([50.68±1.58] GU) after final wear ( P< 0.05). Flowable composites of group A1 and B1 tested in the present setup showed better surface properties compared to their pasty counterpart (group A2 and B2). Conclusions: Within the limit of this study, flowable composites tested in the present research can obtain similar surface polish or even better than the paste composite counterpart.

  8. Guided asteroid deflection by kinetic impact: Mapping keyholes to an asteroid's surface

    Science.gov (United States)

    Chesley, S.; Farnocchia, D.

    2014-07-01

    range from around 1 for a porous, compressible body producing negligible ejecta, to 2 when the ejecta momentum matches the spacecraft momentum, and as high as 5--10 for rocky bodies that produce large, high-velocity ejecta fragments. If the impactor hits the centerpoint of a spherical asteroid the momentum of the escaping ejecta directly adds to the momentum of the impacting asteroid, but if the impact is oblique then the ejecta and spacecraft momenta are added to the asteroid in vector sum. This suggests the possibility that for a given intercept trajectory the asteroid deflection could include guidance by targeting an oblique impact that could steer the asteroid Δ V to a more optimal direction that is different from the relative velocity direction of the spacecraft. An oblique impact decreases the net Δ V magnitude, and yet could significantly increase the net deflection at the time of the threatening Earth encounter. We use asteroid (101955) Bennu, which is the target of the OSIRIS-REx asteroid sample return mission and which has a series of potential Earth impacts in the years from 2175--2196, as an example to demonstrate the effectiveness of the oblique impact. These future potential impacts will occur if the asteroid passes through one of a series of keyholes when the asteroid passes the Earth at roughly the lunar distance from the Earth in 2135. To study the Bennu deflection problem we simulate a hypervelocity spacecraft impact on Bennu in March 2021, after the OSIRIS-REx mission is complete. In our example, the spacecraft arrives from approximately the sunward direction, and targeting ahead or behind the center of the asteroid allows non-negligible transverse accelerations for modest values of β. A given impact location on the asteroid surface yields a given Δ V vector, and our approach starts by mapping the net Δ V components on the surface for an assumed value of β. Knowing the mapping from impact location to Δ V and also the mapping from Δ V to the

  9. Optical Properties and Surface Morphology of Nano-composite PMMA: TiO2 Thin Films

    International Nuclear Information System (INIS)

    Lyly Nyl Ismail; Ahmad Fairoz Aziz; Habibah Zulkefle

    2011-01-01

    There are two nano-composite PMMA: TiO 2 solutions were prepared in this research. First solution is nano-composite PMMA commercially available TiO 2 nanopowder and the second solution is nano-composite PMMA with self-prepared TiO 2 powder. The self-prepared TiO 2 powder is obtained by preparing the TiO 2 sol-gel. Solvo thermal method were used to dry the TiO 2 sol-gel and obtained TiO 2 crystal. Ball millers were used to grind the TiO 2 crystal in order to obtained nano sized powder. Triton-X was used as surfactant to stabilizer the composite between PMMA: TiO 2 . Besides comparing the nano-composite solution, we also studied the effect of the thin films thickness on the optical properties and surface morphology of the thin films. The thin films were deposited by sol-gel spin coating method on glass substrates. The optical properties and surface characterization were measured with UV-VIS spectrometer equipment and atomic force microscopy (AFM). The result showed that nano-composite PMMA with self prepared TiO 2 give high optical transparency than nano-composite PMMA with commercially available TiO 2 nano powder. The results also indicate as the thickness is increased the optical transparency are decreased. Both AFM images showed that the agglomerations of TiO 2 particles are occurred on the thin films and the surface roughness is increased when the thickness is increased. High agglomeration particles exist in the AFM images for nano-composite PMMA: TiO 2 with TiO 2 nano powder compare to the other nano-composite solution. (author)

  10. Effect of different surface treatments on the shear bond strength of nanofilled composite repairs

    Directory of Open Access Journals (Sweden)

    Ghazaleh Ahmadizenouz

    2016-03-01

    Full Text Available Background. Repairing aged composite resin is a challenging process. Many surface treatment options have been proposed to this end. This study evaluated the effect of different surface treatments on the shear bond strength (SBS of nano-filled composite resin repairs. Methods. Seventy-five cylindrical specimens of a Filtek Z350XT composite resin were fabricated and stored in 37°C distilled water for 24 hours. After thermocycling, the specimens were divided into 5 groups according to the following surface treatments: no treatment (group 1; air abrasion with 50-μm aluminum oxide particles (group 2; irradiation with Er:YAG laser beams (group 3; roughening with coarse-grit diamond bur + 35% phosphoric acid (group 4; and etching with 9% hydrofluoric acid for 120 s (group 5. Another group of Filtek Z350XT composite resin samples (4×6 mm was fabricated for the measurement of cohesive strength (group 6. A silane coupling agent and an adhesive system were applied after each surface treatment. The specimens were restored with the same composite resin and thermocycled again. A shearing force was applied to the interface in a universal testing machine. Data were analyzed using one-way ANOVA and post hoc Tukey tests (P < 0.05. Results. One-way ANOVA indicated significant differences between the groups (P < 0.05. SBS of controls was significantly lower than the other groups; differences between groups 2, 3, 4, 5 and 6 were not significant. Surface treatment with diamond bur + 35% phosphoric acid resulted in the highest bond strength. Conclusion. All the surface treatments used in this study improved the shear bond strength of nanofilled composite resin used.

  11. 3D Surface Mapping of Capsule Fill-Tube Assemblies used in Laser-Driven Fusion Targets

    Energy Technology Data Exchange (ETDEWEB)

    Buice, E S; Alger, E T; Antipa, N A; Bhandarkar, S D; Biesiada, T A; Conder, A D; Dzenitis, E G; Flegel, M S; Hamza, A V; Heinbockel, C L; Horner, J; Johnson, M A; Kegelmeyer, L M; Meyer, J S; Montesanti, R C; Reynolds, J L; Taylor, J S; Wegner, P J

    2011-02-18

    This paper presents the development of a 3D surface mapping system used to measure the surface of a fusion target Capsule Fill-Tube Assembly (CFTA). The CFTA consists of a hollow Ge-doped plastic sphere, called a capsule, ranging in outer diameter between 2.2 mm and 2.6 mm and an attached 150 {micro}m diameter glass-core fill-tube that tapers down to a 10{micro} diameter at the capsule. The mapping system is an enabling technology to facilitate a quality assurance program and to archive 3D surface information of each capsule used in fusion ignition experiments that are currently being performed at the National Ignition Facility (NIF). The 3D Surface Mapping System is designed to locate and quantify surface features with a height of 50 nm and 300 nm in width or larger. Additionally, the system will be calibrated such that the 3D measured surface can be related to the capsule surface angular coordinate system to within 0.25 degree (1{sigma}), which corresponds to approximately 5 {micro}m linear error on the capsule surface.

  12. 3D Surface Mapping of Capsule Fill-Tube Assemblies used in Laser-Driven Fusion Targets

    International Nuclear Information System (INIS)

    Buice, E.S.; Alger, E.T.; Antipa, N.A.; Bhandarkar, S.D.; Biesiada, T.A.; Conder, A.D.; Dzenitis, E.G.; Flegel, M.S.; Hamza, A.V.; Heinbockel, C.L.; Horner, J.; Johnson, M.A.; Kegelmeyer, L.M.; Meyer, J.S.; Montesanti, R.C.; Reynolds, J.L.; Taylor, J.S.; Wegner, P.J.

    2011-01-01

    This paper presents the development of a 3D surface mapping system used to measure the surface of a fusion target Capsule Fill-Tube Assembly (CFTA). The CFTA consists of a hollow Ge-doped plastic sphere, called a capsule, ranging in outer diameter between 2.2 mm and 2.6 mm and an attached 150 (micro)m diameter glass-core fill-tube that tapers down to a 10(micro) diameter at the capsule. The mapping system is an enabling technology to facilitate a quality assurance program and to archive 3D surface information of each capsule used in fusion ignition experiments that are currently being performed at the National Ignition Facility (NIF). The 3D Surface Mapping System is designed to locate and quantify surface features with a height of 50 nm and 300 nm in width or larger. Additionally, the system will be calibrated such that the 3D measured surface can be related to the capsule surface angular coordinate system to within 0.25 degree (1σ), which corresponds to approximately 5 (micro)m linear error on the capsule surface.

  13. Composite Membrane with Underwater-Oleophobic Surface for Anti-Oil-Fouling Membrane Distillation.

    Science.gov (United States)

    Wang, Zhangxin; Hou, Deyin; Lin, Shihong

    2016-04-05

    In this study, we fabricated a composite membrane for membrane distillation (MD) by modifying a commercial hydrophobic polyvinylidene fluoride (PVDF) membrane with a nanocomposite coating comprising silica nanoparticles, chitosan hydrogel and fluoro-polymer. The composite membrane exhibits asymmetric wettability, with the modified surface being in-air hydrophilic and underwater oleophobic, and the unmodified surface remaining hydrophobic. By comparing the performance of the composite membrane and the pristine PVDF membrane in direct contact MD experiments using a saline emulsion with 1000 ppm crude oil (in water), we showed that the fabricated composite membrane was significantly more resistant to oil fouling compared to the pristine hydrophobic PVDF membrane. Force spectroscopy was conducted for the interaction between an oil droplet and the membrane surface using a force tensiometer. The difference between the composite membrane and the pristine PVDF membrane in their interaction with an oil droplet served to explain the difference in the fouling propensities between these two membranes observed in MD experiments. The results from this study suggest that underwater oleophobic coating can effectively mitigate oil fouling in MD operations, and that the fabricated composite membrane with asymmetric wettability can enable MD to desalinate hypersaline wastewater with high concentrations of hydrophobic contaminants.

  14. Microstructure Characterization of Al-TiC Surface Composite Fabricated by Friction Stir Processing

    Science.gov (United States)

    Shiva, Apireddi; Cheepu, Muralimohan; Charan Kantumuchu, Venkata; Kumar, K. Ravi; Venkateswarlu, D.; Srinivas, B.; Jerome, S.

    2018-03-01

    Titanium carbide (TiC) is an exceedingly hard and wear refractory ceramic material. The surface properties of the material are very important and the corrosion, wear and fatigue resistance behaviour determines its ability and applications. It is necessary to modify the surface properties of the materials to enhance their performance. The present work aims on developing a new surface composite using commercially pure aluminum and TiC reinforcement powder with a significant fabrication technique called friction stir processing (FSP). The metal matrix composite of Al/TiC has been developed without any defects formation to investigate the particles distribution in the composite, microstructural changes and mechanical properties of the material. The microstructural observations exhibited that the grain refinement in the nugget compared to the base metal and FSP without TiC particles. The developed composite properties showed substantial improvement in micro-hardness, friction factor, wear resistance and microstructural characteristics in comparison to parent metal. On the other side, the ductility of the composite specimens was diminished over the substrate. The FSPed specimens were characterised using X-ray diffraction technique and revealed that the formation of AlTi compounds and the presence of Ti phases in the matrix. The microstructures of the samples illustrated the uniform distribution of particles in the newly developed metal matrix composite.

  15. The Origin of the Compositional Diversity of Mercury's Surface Constrained From Experimental Melting of Enstatite Chondrites

    Science.gov (United States)

    Boujibar, A.; Righter, K.; Pando, K.; Danielson, L.

    2015-01-01

    Mercury is known as an endmember planet as it is the most reduced terrestrial planet with the highest core/mantle ratio. MESSENGER spacecraft has shown that its surface is FeO-poor (2-4 wt%) and Srich (up to 6-7 wt%), which confirms the reducing nature of its silicate mantle. Moreover, high resolution images revealed large volcanic plains and abundant pyroclastic deposits, suggesting important melting stages of the Mercurian mantle. This interpretation was confirmed by the high crustal thickness (up to 100 km) derived from Mercury's gravity field. This is also corroborated by a recent experimental result that showed that Mercurian partial melts are expected to be highly buoyant within the Mercurian mantle and could have risen from depths as high as the core-mantle boundary. In addition MESSENGER spacecraft provided relatively precise data on major elemental compositions of Mercury's surface. These results revealed important chemical and mineralogical heterogeneities that suggested several stages of differentiation and re-melting processes. However, the extent and nature of compositional variations produced by partial melting remains poorly constrained for the particular compositions of Mercury (very reducing conditions, low FeO-contents and high sulfur-contents). Therefore, in this study, we investigated the processes that lead to the various compositions of Mercury's surface. Melting experiments with bulk Mercury-analogue compositions were performed and compared to the compositions measured by MESSENGER.

  16. Influence of Mechanical and Chemical Degradation in the Surface Roughness, Gloss, and Color of Microhybrid Composites.

    Science.gov (United States)

    Lemos, Cleidiel Aa; Mauro, Silvio J; Dos Santos, Paulo H; Briso, Andre Lf; Fagundes, Ticiane C

    2017-04-01

    The aim of this study was to investigate the association of different degradations on the roughness, gloss, and color changes of microhybrid composites. Ten specimens were prepared for Charisma, Amelogen Plus, Point 4, and Opallis resins. Surfaces were polished and baseline measurements of roughness, gloss, and color were recorded. Specimens were then submitted to chemical and mechanical challenges, and the specimens were reevaluated. Roughness and gloss were analyzed by Kruskal -Wallis and Dunn's test (p one-way analysis of variance and Tukey's tests (p gloss (p gloss, there was no difference between composites before challenges. However, all composites showed a significant increase of roughness after challenges, with highest values for Charisma. The gloss was influenced by challenges, evidencing the best gloss for Point 4. Charisma showed the highest value of color change. There was no correlation between surface roughness and gloss for the initial analysis, and after the challenges. Composites were influenced by association of challenges, and Charisma showed the highest changes for roughness, gloss, and color. The type of composite resin influenced the properties of materials, which are surface roughness, gloss, and color change. The dentist should be aware of the performance of different brands, to choose the correct required composite resin for each type of patient or region to be restored.

  17. Fracture Surface Morphology and Impact Strength of Cellulose/PLA Composites.

    Science.gov (United States)

    Gao, Honghong; Qiang, Tao

    2017-06-07

    Polylactide (PLA)-based composite materials reinforced with ball-milled celluloses were manufactured by extrusion blending followed by injection molding. Their surface morphology from impact fracture were imaged with scanning electron microscopy (SEM) and investigated by calculating their fractal dimensions. Then, linear regression was used to explore the relationship between fractal dimension and impact strength of the resultant cellulose/PLA composite materials. The results show that filling the ball-milled celluloses into PLA can improve the impact toughness of PLA by a minimum of 38%. It was demonstrated that the fracture pattern of the cellulose/PLA composite materials is different from that of pristine PLA. For the resultant composite materials, the fractal dimension of the impact fractured surfaces increased with increasing filling content and decreasing particle size of the ball-milled cellulose particles. There were highly positive correlations between fractal dimension of the fractured surfaces and impact strength of the cellulose/PLA composites. However, the linearity between fractal dimension and impact strength were different for the different methods, due to their different R-squared values. The approach presented in this work will help to understand the structure-property relationships of composite materials from a new perspective.

  18. 3-D FEM Modeling of fiber/matrix interface debonding in UD composites including surface effects

    International Nuclear Information System (INIS)

    Pupurs, A; Varna, J

    2012-01-01

    Fiber/matrix interface debond growth is one of the main mechanisms of damage evolution in unidirectional (UD) polymer composites. Because for polymer composites the fiber strain to failure is smaller than for the matrix multiple fiber breaks occur at random positions when high mechanical stress is applied to the composite. The energy released due to each fiber break is usually larger than necessary for the creation of a fiber break therefore a partial debonding of fiber/matrix interface is typically observed. Thus the stiffness reduction of UD composite is contributed both from the fiber breaks and from the interface debonds. The aim of this paper is to analyze the debond growth in carbon fiber/epoxy and glass fiber/epoxy UD composites using fracture mechanics principles by calculation of energy release rate G II . A 3-D FEM model is developed for calculation of energy release rate for fiber/matrix interface debonds at different locations in the composite including the composite surface region where the stress state differs from the one in the bulk composite. In the model individual partially debonded fiber is surrounded by matrix region and embedded in a homogenized composite.

  19. Surface modification and particles size distribution control in nano-CdS/polystyrene composite film

    International Nuclear Information System (INIS)

    Min Zhirong; Ming Qiuzhang; Hai Chunliang; Han Minzeng

    2003-01-01

    Preparation of nano-CdS particles with surface thiol modification by microemulsion method and their influences on the particle size distribution in highly filled polystyrene-based composites were studied. The modified nano-CdS was characterized by X-ray photoelectron spectroscopy (XPS), light absorption and emission measurements to reveal the morphologies of the surface modifier, which are consistent with the surface molecules packing calculation. The morphologies of the surface modifier exerted a great influence not only on the optical performance of the particles themselves, but also on the size distribution of the particle in polystyrene matrix. A monolayer coverage with tightly packed thiol molecules was believed to be most effective in promoting a uniform particle size distribution and eliminating the surface defects that cause radiationless recombination. Control of the particles size distribution in polystyrene can be attained by adjusting surface coverage status of the thiol molecules based on the strong interaction between the surface modifier and the matrix

  20. Color and opacity of composites protected with surface sealants and submitted to artificial accelerated aging.

    Science.gov (United States)

    Aguilar, Fabiano Gamero; Roberti Garcia, Lucas da Fonseca; Cruvinel, Diogo Rodrigues; Sousa, Ana Beatriz Silva; de Carvalho Panzeri Pires-de-Souza, Fernanda

    2012-01-01

    To evaluate the color similarity, stability and opacity of composites (TPH, Charisma, and Concept, shade A2) protected with surface sealants (Fortify Plus and Biscover) and cyanoacrylate (Super Bonder). Forty specimens of each composite were made and separated into 4 groups (n=10) according to the surface protection: GI - without sealant; GII - cyanoacrylate; GIII - Fortify Plus; GIV - Biscover. Color and opacity readings were taken before and after Artificial Acelerated Aging (AAA) and the values obtained for color stability were submitted to statistical analysis by 2-way ANOVA and Bonferroni's test (P<.05). The values acquired for color similarity were submitted to 1-way ANOVA and Tukey's test (P<.05). The specimen sufaces were compared before and after AAA using Scanning Electronic Microscopy (SEM). Studied composites did not present the same values for the coordinates L*, a* and b * before AAA, indicating that there was no color similarity among them. All composites presented color alteration after AAA with clinically unacceptable values. Protected groups presented lower opacity variation after AAA, in comparison with the control goup. SEM evaluation demonstrated that AAA increased the surface irregularities in all of the studied groups. Surface sealants were not effective in maintaining composite color, but were able to maintain opacity.

  1. Effect of fiber surface state on mechanical properties of Cf/Si-O-C composites

    International Nuclear Information System (INIS)

    Wang Song; Chen Zhaohui; Ma Qingsong; Hu Haifeng; Zheng Wenwei

    2005-01-01

    Three-dimensional braided carbon fiber reinforced silicon oxycarbide composites (3D-B C f /Si-O-C) were fabricated via a polysiloxane infiltration and pyrolysis route. The effects of fiber surface state on microstructure and mechanical properties of C f /Si-O-C composites were investigated. The change of carbon fiber surface state was achieved via heat treatment in vacuum. The results showed that heat treatment decreased carbon fiber surface activity due to the decrease of the amount of oxygen and nitrogen atoms. The C f /Si-O-C composites fabricated from the carbon fiber with low surface activity had excellent mechanical properties, which resulted from perfect interfacial bonding and good in situ fiber strength. The flexural strength and fracture toughness of the C f /Si-O-C composites from the treated fiber were 534 MPa and 23.4 MPa m 1/2 , respectively, which were about 7 and 11 times more than those of the composites from the as-received carbon fiber, respectively

  2. Effect of Artificial Aging Protocols on Surface Gloss of Resin Composites

    OpenAIRE

    Rocha, Rafael Santos; Oliveira, Amanda Carvalho; Caneppele, Taciana Marco Ferraz; Bresciani, Eduardo

    2017-01-01

    The purpose of this study was to evaluate the effect of aging protocols on surface gloss of composites. Cylindrical resin composite specimens (6?mm in diameter, 1?mm thick) were fabricated and divided into three groups (N = 60): microfilled (MiFi), nanohybrid (NaHy), and nanofilled (NaFi). Specimens were distributed into four aging subgroups: thermocycling (5? to 55?C, 15,000 cycles); ethanol immersion (15 days); brushing (10,750 cycles); and light aging (216?h). Surface gloss readings (Novo-...

  3. Microstructure and hardness of WC-Co particle reinforced iron matrix surface composite

    Directory of Open Access Journals (Sweden)

    Zhang Peng

    2013-11-01

    Full Text Available In this study, a high Cr cast iron surface composite material reinforced with WC-Co particles 2-6 mm in size was prepared using a pressureless sand mold infiltration casting technique. The composition, microstructure and hardness were determined by means of energy dispersive spectrometry (EDS, electron probe microanalysis (EPMA, scanning electron microscope (SEM and Rockwell hardness measurements. It is determined that the obtained composite layer is about 15 mm thick with a WC-Co particle volumetric fraction of ~38%. During solidification, interface reaction takes place between WC-Co particles and high chromium cast iron. Melting and dissolving of prefabricated particles are also found, suggesting that local Co melting and diffusion play an important role in promoting interface metallurgical bonding. The composite layer is composed of ferrite and a series of carbides, such as (Cr, W, Fe23C6, WC, W2C, M6C and M12C. The inhomogeneous hardness in the obtained composite material shows a gradient decrease from the particle reinforced metal matrix composite layer to the matrix layer. The maximum hardness of 86.3 HRA (69.5 HRC is obtained on the particle reinforced surface, strongly indicating that the composite can be used as wear resistant material.

  4. In situ mapping of radionuclides in subsurface and surface soils: 1994 Summary report

    International Nuclear Information System (INIS)

    Schilk, A.J.; Hubbard, C.W.; Knopf, M.A.; Abel, K.H.

    1995-04-01

    Uranium production and support facilities at several DOE sites occasionally caused local contamination of some surface and subsurface soils. The thorough cleanup of these sites is a major public concern and a high priority for the US Department of Energy, but before any effective remedial protocols can be established, the three-dimensional distributions of target contaminants must be characterized. Traditional means of measuring radionuclide activities in soil are cumbersome, expensive, time-consuming, and often do not accurately reflect conditions over very large areas. New technologies must be developed, or existing ones improved, to allow cheaper, faster, and safer characterization of radionuclides in soils at these sites. The Pacific Northwest Laboratory (PNL) was tasked with adapting, developing, and demonstrating technologies to measure uranium in surface and subsurface soils. In partial completion of this effort, PNL developed an improved in situ gamma-ray spectrometry system to satisfy the technical requirements. This document summarizes fiscal-year 1994 efforts at PNL to fulfill requirements for TTP number-sign 321103 (project number-sign 19307). These requirements included (a) developing a user-friendly software package for reducing field-acquired gamma-ray spectra, (b) constructing an improved data-acquisition hardware system for use with high-purity germanium detectors, (c) ensuring readiness to conduct field mapping exercises as specified by the sponsor, (d) evaluating the in situ gamma-ray spectrometer for the determination of uranium depth distribution, and (e) documenting these efforts

  5. Mapping global surface water inundation dynamics using synergistic information from SMAP, AMSR2 and Landsat

    Science.gov (United States)

    Du, J.; Kimball, J. S.; Galantowicz, J. F.; Kim, S.; Chan, S.; Reichle, R. H.; Jones, L. A.; Watts, J. D.

    2017-12-01

    A method to monitor global land surface water (fw) inundation dynamics was developed by exploiting the enhanced fw sensitivity of L-band (1.4 GHz) passive microwave observations from the Soil Moisture Active Passive (SMAP) mission. The L-band fw (fwLBand) retrievals were derived using SMAP H-polarization brightness temperature (Tb) observations and predefined L-band reference microwave emissivities for water and land endmembers. Potential soil moisture and vegetation contributions to the microwave signal were represented from overlapping higher frequency Tb observations from AMSR2. The resulting fwLBand global record has high temporal sampling (1-3 days) and 36-km spatial resolution. The fwLBand annual averages corresponded favourably (R=0.84, pretrievals showed favourable classification accuracy for water (commission error 31.84%; omission error 28.08%) and land (commission error 0.82%; omission error 0.99%) and seasonal wet and dry periods when compared to independent water maps derived from Landsat-8 imagery. The new fwLBand algorithms and continuing SMAP and AMSR2 operations provide for near real-time, multi-scale monitoring of global surface water inundation dynamics, potentially benefiting hydrological monitoring, flood assessments, and global climate and carbon modeling.

  6. High-Resolution Mapping of Urban Surface Water Using ZY-3 Multi-Spectral Imagery

    Directory of Open Access Journals (Sweden)

    Fangfang Yao

    2015-09-01

    Full Text Available Accurate information of urban surface water is important for assessing the role it plays in urban ecosystem services under the content of urbanization and climate change. However, high-resolution monitoring of urban water bodies using remote sensing remains a challenge because of the limitation of previous water indices and the dark building shadow effect. To address this problem, we proposed an automated urban water extraction method (UWEM which combines a new water index, together with a building shadow detection method. Firstly, we trained the parameters of UWEM using ZY-3 imagery of Qingdao, China. Then we verified the algorithm using five other sub-scenes (Aksu, Fuzhou, Hanyang, Huangpo and Huainan ZY-3 imagery. The performance was compared with that of the Normalized Difference Water Index (NDWI. Results indicated that UWEM performed significantly better at the sub-scenes with kappa coefficients improved by 7.87%, 32.35%, 12.64%, 29.72%, 14.29%, respectively, and total omission and commission error reduced by 61.53%, 65.74%, 83.51%, 82.44%, and 74.40%, respectively. Furthermore, UWEM has more stable performances than NDWI’s in a range of thresholds near zero. It reduces the over- and under-estimation issues which often accompany previous water indices when mapping urban surface water under complex environmental conditions.

  7. Laser electro-optic system for rapid three-dimensional /3-D/ topographic mapping of surfaces

    Science.gov (United States)

    Altschuler, M. D.; Altschuler, B. R.; Taboada, J.

    1981-01-01

    It is pointed out that the generic utility of a robot in a factory/assembly environment could be substantially enhanced by providing a vision capability to the robot. A standard videocamera for robot vision provides a two-dimensional image which contains insufficient information for a detailed three-dimensional reconstruction of an object. Approaches which supply the additional information needed for the three-dimensional mapping of objects with complex surface shapes are briefly considered and a description is presented of a laser-based system which can provide three-dimensional vision to a robot. The system consists of a laser beam array generator, an optical image recorder, and software for controlling the required operations. The projection of a laser beam array onto a surface produces a dot pattern image which is viewed from one or more suitable perspectives. Attention is given to the mathematical method employed, the space coding technique, the approaches used for obtaining the transformation parameters, the optics for laser beam array generation, the hardware for beam array coding, and aspects of image acquisition.

  8. Point contact tunneling spectroscopy apparatus for large scale mapping of surface superconducting properties

    Energy Technology Data Exchange (ETDEWEB)

    Groll, Nickolas; Pellin, Michael J. [Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); Zasadzinksi, John F. [Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Proslier, Thomas, E-mail: prolier@anl.gov [Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States); High Energy Physics Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States)

    2015-09-15

    We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature T{sub C}) and density of states over large surface areas with size up to mm{sup 2}. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices.

  9. Mapping of upper electronic reaction surfaces by tuned laser photolysis and by absorption and emission spectroscopies

    International Nuclear Information System (INIS)

    Morgan, M.A.

    1989-07-01

    Potential energy surfaces for photorotamerization of two intramolecularly hydrogen-bonded molecules, o-hydroxybenzaldehyde (OHBA) and methyl salicylate (MS), isolated in cryogenic matrices have been spectroscopically mapped. In addition, the external heavy atom effect of krypton and xenon matrices on the coupling between the S 1 and T 1 surfaces of 4-(dimethylamino)benzonitrile has been examined. Heavy atom matrices are known to increase rates of spin-forbidden processes. The phosphorescence intensity of DMABN increases in krypton and xenon matrices, while the fluorescence intensity, and phosphorescence and fluorescence lifetimes, decrease. These effects are interpreted in terms of a model in which the phosphorescence rate constant increases 300-fold in xenon compared to argon, while the rate constants for intersystem crossing and nonradiative relaxation from the triplet state increase by factors of less than 5. Lifetime measurements in argon matrices doped with heavy atoms indicate that even one heavy atom neighbor has a significant effect on both singlet and triplet lifetimes. 78 refs., 35 figs., 15 tabs

  10. Estimating surface soil erosion losses and mapping erosion risk for Yusufeli micro-catchment (Artvin

    Directory of Open Access Journals (Sweden)

    Mustafa Tüfekçioğlu

    2016-10-01

    Full Text Available Sheet erosion, one of the most important types of water erosion, takes place on the top soil as tiny soil layer movement that affects lake and stream ecosystem. This type of erosion is very important because the productive soil layer on the top soil can be lost in a very short period of time. The goal of this study was to quantify the amount of surface (sheet and rill soil erosion, and to identify areas under high erosion risk within the study area at Yusufeli province in Artvin by using RUSLE erosion methodology. As a result of the study it was found that the average annual potential soil loss by surface erosion was 3.6 ton ha-1yr-1. Additionally, the maps produced and conclusions reached by the study revealed that the areas of high erosion risk were identified spatially and measures to control erosion on some of these high risk areas can be possible with appropriate erosion control techniques.

  11. Evaluation of periodontal status adjacent to interproximal surfaces restored with composite resin, in comparison with non-restored interproximal surfaces

    Directory of Open Access Journals (Sweden)

    Elvia Christina Barros de Almeida

    2008-01-01

    Full Text Available Objective: The purpose of this study was to evaluate the periodontal status of interproximal surfaces restored with composite resin, in comparison with non-restored interproximal surfaces. Methods: In 65 patients, we analyzed 145 restored surfaces and 145 non-restored surfaces. Results: Most of the restored surfaces (54.3% showed radiographic alterations, which was shown to be higher among restorations with clinically detected proximal excess (56.8% x 52.8%; with lack of restorative material (64.5% x 51.4%; in restorations with proximal overhang (67.7% x 44.4%; in teeth with gingival inflammation?/bleeding (55.1% x 40.0% and in teeth with probing depth exceeding 3 mm (64.3% x 52.9%. However, there were no significant associations for these variables. Of the non-restored surfaces, 24.4% showed radiographic alterations, however there were no significant associations. Conclusion: The results showed a statistical significance for radiographic alterations in restored and non-restored surfaces.

  12. Preparation of electrodes on cfrp composites with low contact resistance comprising laser-based surface pre-treatment

    KAUST Repository

    Almuhammadi, Khaled Hamdan; Lubineau, Gilles; Alfano, Marco Francesco; Buttner, Ulrich

    2016-01-01

    Various examples are provided related to the preparation of electrodes on carbon fiber reinforced polymer (CFRP) composites with low contact resistance. Laser-based surface preparation can be used for bonding to CFRP composites. In one example, a

  13. Comparative evaluation of effect of different polishing systems on surface roughness of composite resin: An in vitro study.

    Science.gov (United States)

    Chour, Rashmi G; Moda, Aman; Arora, Arpana; Arafath, Muhmmed Y; Shetty, Vikram K; Rishal, Yousef

    2016-08-01

    Satisfactory composite restoration depends upon its smooth finish, quality of polishing agents, type of composite material used, and its composition. The present study evaluated the effect of different polishing systems on the surface roughness of composite resin. Forty discs of composite were prepared and equally subjected to different finishing and polishing procedures; (i) unpolished control group, (ii) sof-lex discs, (iii) diamond tips, and (iv) Astrobrush groups. Later, the surface roughness for the entire specimen was evaluated using Profilomotor. Data were tabulated and statistically analyzed using analysis of variance and Tukey's test at significance level of 0.001. Composite surface roughness after polishing was statistically significant between the groups. Sof-lex group produced lesser surface roughness compared to control, Astrobrush, and diamond group. The present study indicated that diamond tips can be used to remove rough surface whereas sof-lex can be used for final finish and polish of the composite restoration.

  14. Induced wettability and surface-volume correlation of composition for bovine bone derived hydroxyapatite particles

    Science.gov (United States)

    Maidaniuc, Andreea; Miculescu, Florin; Voicu, Stefan Ioan; Andronescu, Corina; Miculescu, Marian; Matei, Ecaterina; Mocanu, Aura Catalina; Pencea, Ion; Csaki, Ioana; Machedon-Pisu, Teodor; Ciocan, Lucian Toma

    2018-04-01

    Hydroxyapatite powders characteristics need to be determined both for quality control purposes and for a proper control of microstructural features of bone reconstruction products. This study combines bulk morphological and compositional analysis methods (XRF, SEM-EDS, FT-IR) with surface-related methods (XPS, contact angle measurements) in order to correlate the characteristics of hydroxyapatite powders derived from bovine bone for its use in medical applications. An experimental approach for correlating the surface and volume composition was designed based on the analysis depth of each spectral method involved in the study. Next, the influences of powder particle size and forming method on the contact angle between water drops and ceramic surface were evaluated for identifying suitable strategies of tuning hydroxyapatite's wettability. The results revealed a preferential arrangement of chemical elements at the surface of hydroxyapatite particles which could induce a favourable material behaviour in terms of sinterability and biological performance.

  15. Surge-Resistant Nanocomposite Enameled Wire Using Silica Nanoparticles with Binary Chemical Compositions on the Surface

    Directory of Open Access Journals (Sweden)

    Jeseung Yoo

    2015-01-01

    Full Text Available We developed polyesterimide (PEI nanocomposite enameled wires using surface-modified silica nanoparticles with binary chemical compositions on the surface. The modification was done using silanes assisted by ultrasound, which facilitated high density modification. Two different trimethoxysilanes were chosen for the modification on the basis of resemblance of chemical compositions on the silica surface to PEI varnish. The surface-modified silica was well dispersed in PEI varnish, which was confirmed by optical observation and viscosity measurement. The glass transition temperature of the silica-PEI nanocomposite increased with the silica content. The silica-dispersed PEI varnish was then used for enameled wire fabrication. The silica-PEI nanocomposite enameled wire exhibited a much longer lifetime compared to that of neat PEI enameled wire in partial discharge conditions.

  16. Evaluation of Mechanical Property of Carbon Fiber/Polypropylene Composite According to Carbon Fiber Surface Treatment

    International Nuclear Information System (INIS)

    Han, Song Hee; Oh, Hyun Ju; Kim, Seong Su

    2013-01-01

    In this study, the mechanical properties of a carbon fiber/polypropylene composite were evaluated according to the carbon fiber surface treatment. Carbon fiber surface treatments such as silane coupling agents and plasma treatment were performed to enhance the interfacial strength between carbon fibers and polypropylene. The treated carbon fiber surface was characterized by XP S, Sem, and single-filament tensile test. The interlaminar shear strength (Ilks) of the composite with respect to the surface treatment was determined by a short beam shear test. The test results showed that the Ilks of the plasma-treated specimen increased with the treatment time. The Ilks of the specimen treated with a silane coupling agent after plasma treatment increased by 48.7% compared to that of the untreated specimen

  17. Superficial roughness on composite surface, composite enamel and composite dentin junctions after different finishing and polishing procedures. Part I: roughness after treatments with tungsten carbide vs diamond burs.

    Science.gov (United States)

    Ferraris, Federico; Conti, Alessandro

    2014-01-01

    The aim of this study is to investigate different instruments for finishing composite restorations, as well as examining different surfaces and interfaces of the same restoration. The null hypothesis is represented by the fact that there are no significant differences on roughness of composite restorations finishing between tungsten carbide and diamond burs, furthermore the null hypothesis is that there are no significant differences on roughness between finishing on composite surfaces (C), compositeenamel (CE) and composite-dentin (CD) interfaces. The study was performed on 28 teeth, and class V cavities were prepared on the extracted teeth. Restorations were done in Filtek XTE nanofilled composite (3M Espe) in a standardized method, to then be finished. A comparison was made in the phase 1 between tungsten carbide burs (16 blades), diamond burs (46 μm), with a similar shape by the same manufacturer (Komet). Each surface received 5 bur applications. Consequently, an analysis with a profilometer was performed. Phase 2 involved further confrontation of ulterior finishing with ultrafine tungsten carbide burs (30 blades) and with extra and ultrafine diamond burs (25 and 8 μm) (the same shape as previously mentioned). A second analysis was then performed with a profilometer. All measurements were taken on C surfaces, CE and CD interfaces. Statistical analyses were carried out with c2 test (a = 0.05). The finishing procedures with fine grit or toothing burs gave a better smoothness with tungsten carbide burs compared to diamond burs. While with the ultrafine grit no significant differences were noted between tungsten carbide and diamond burs on the CE and CD interfaces, the diamond bur left less superficial roughness on the C surfaces. With regards to the superficial roughness of the different areas of restoration, it can be concluded that: minor roughness was detected on C surfaces, while the CD interface had the most superficial roughness, regardless of whether the

  18. Controlled surface chemistry of diamond/β-SiC composite films for preferential protein adsorption.

    Science.gov (United States)

    Wang, Tao; Handschuh-Wang, Stephan; Yang, Yang; Zhuang, Hao; Schlemper, Christoph; Wesner, Daniel; Schönherr, Holger; Zhang, Wenjun; Jiang, Xin

    2014-02-04

    Diamond and SiC both process extraordinary biocompatible, electronic, and chemical properties. A combination of diamond and SiC may lead to highly stable materials, e.g., for implants or biosensors with excellent sensing properties. Here we report on the controllable surface chemistry of diamond/β-SiC composite films and its effect on protein adsorption. For systematic and high-throughput investigations, novel diamond/β-SiC composite films with gradient composition have been synthesized using the hot filament chemical vapor deposition (HFCVD) technique. As revealed by scanning electron microscopy (SEM), the diamond/β-SiC ratio of the composite films shows a continuous change from pure diamond to β-SiC over a length of ∼ 10 mm on the surface. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) was employed to unveil the surface termination of chemically oxidized and hydrogen treated surfaces. The surface chemistry of the composite films was found to depend on diamond/β-SiC ratio and the surface treatment. As observed by confocal fluorescence microscopy, albumin and fibrinogen were preferentially adsorbed from buffer: after surface oxidation, the proteins preferred to adsorb on diamond rather than on β-SiC, resulting in an increasing amount of proteins adsorbed to the gradient surfaces with increasing diamond/β-SiC ratio. By contrast, for hydrogen-treated surfaces, the proteins preferentially adsorbed on β-SiC, leading to a decreasing amount of albumin adsorbed on the gradient surfaces with increasing diamond/β-SiC ratio. The mechanism of preferential protein adsorption is discussed by considering the hydrogen bonding of the water self-association network to OH-terminated surfaces and the change of the polar surface energy component, which was determined according to the van Oss method. These results suggest that the diamond/β-SiC gradient film can be a promising material for biomedical applications which

  19. Computer-generated maps of lunar composition from gamma ray data

    International Nuclear Information System (INIS)

    Arnold, J.R.; Metzger, A.E.; Reedy, R.C.

    1977-01-01

    The system of Eliason and Soderblom (1977) has been used to process some of the gamma ray mapping data obtained on Apollo 15 and 16. Old results are confirmed and new information obtained, especially with respect to the distribution of Fe over the area mapped, and the correlation of Fe with the radioactive elements. The results are displayed

  20. Surface composition of pull-apart bands in Argadnel Regio, Europa: Evidence of localized cryovolcanic resurfacing during basin formation

    Science.gov (United States)

    Prockter, Louise M.; Shirley, James H.; Dalton, James B.; Kamp, L.

    2017-03-01

    We combine Galileo Solid State Imager (SSI) and Near-Infrared Mapping Spectrometer (NIMS) data to investigate the composition of pull-apart bands in Europa's Argadnel Regio. Using spectral linear mixture modeling employing cryogenic laboratory reference spectra, we find that bands of intermediate age ("grey" bands) are compositionally distinct from bands that are stratigraphically younger ("dark" bands). The grey bands have higher abundances of larger ice grains and lower abundances of hydrated salts than the dark bands; both of these tendencies are statistically significant at the 1% level. The grey and dark bands have similar abundances of hexahydrite, a material which is relatively stable under irradiation; however, the derived abundances of frozen magnesium sulfate brine and of mirabilite, which are more susceptible to fragmentation by radiation, are significantly higher in the dark bands than in the grey bands. These results are consistent with a physical model in which the differences in composition and in ice grain sizes are linked to space weathering and radiolytic processing levels; the grey bands have presumably undergone higher levels of processing, due to being exposed on Europa's surface for a longer period of time. One prominent wedge-shaped band exhibits an anomalous albedo variation across its northern portion, appearing dark in its top third, and grey in its southernmost two-thirds. We find that the dark part of the band has a modeled composition that is in-family with other dark bands, while the grey portion has a modeled composition that is indistinguishable from other grey bands in the study area. Because these variations cannot easily be attributed to the band's formation mechanism (bands open sequentially along a central axis), we surmise that the northern part has been resurfaced, probably in response to the formation of a large topographic basin that cuts through the band. Faulting accompanying basin formation may provide conduits allowing

  1. Surface geometry of three packable and one hybrid composite after polishing.

    Science.gov (United States)

    Jung, Martin; Bruegger, Hilka; Klimek, Joachim

    2003-01-01

    This study evaluated the surface quality of four composite materials after polishing with six different polishing techniques. Eighty specimens were made using three packable composites (Definite/Degussa, SureFil/ Dentsply and Solitaire/Heraeus-Kulzer) and one hybrid composite (Herculite XRV/Kerr). Five specimens of each material were polished using flexible Sof-Lex discs. The remaining 75 specimens of each composite were prepared using three finishing protocols: a single 30 microm diamond (n = 25), two finishing diamonds (30/20 microm; n = 25) and a 30 microm diamond followed by a tungsten carbide finishing bur (n = 25). Final polishing of each of the three finishing groups was accomplished with SuperBuff, Diafix-oral, OneGloss, Astropol and HaWe Composite Polishers (n = 5, each). Surface roughness was evaluated quantitatively by laser-stylus profilometry. Average roughness (R(a)) was calculated; statistical analysis of the data was performed with two-way ANOVA and Scheffé post-hoc tests. The polished surfaces were examined qualitatively by SEM. The results showed significant effects on surface roughness from the different composites (p = 0.011) and polishing systems (p < 0.001). After polishing, the Solitaire surfaces (R(a) = 0.72 microm) were smoother than Definite (R(a) = 0.87 microm) and SureFil (R(a) = 0.89 microm) and significantly smoother than Herculite (R(a) = 0.92 microm; p = 0.011). Three of the polishing methods (SuperBuff, Diafix-oral and Astropol) achieved lower R(a)-values than Sof-Lex discs. The polishing quality of the one-step systems SuperBuff and Diafix-oral was strongly affected by the initial finishing protocol.

  2. Effect of metal surface composition on deposition behavior of stainless steel component dissolved in liquid sodium

    International Nuclear Information System (INIS)

    Yokota, Norikatsu; Shimoyashiki, Shigehiro

    1988-01-01

    Deposition behavior of corrosion products has been investigated to clarify the effect of metal surface composition on the deposition process in liquid sodium. For the study a sodium loop made of Type 304 stainless steel was employed. Deposition test pieces, which were Type 304 stainless steel, iron, nickel or Inconel 718, were immersed in the sodium pool of the test pot. Corrosion test pieces, which were Type 304 stainless steel, 50 at% Fe-50 at%Mn and Inconel 718, were set in a heater pin assembly along the axial direction of the heater pin surface. Sodium temperatures at the outlet and inlet of the heater pin assembly were controlled at 943 and 833 K, respectively. Sodium was purified at a cold trap temperature of 393 K and the deposition test was carried out for 4.3 x 10 2 - 2.9 x 10 4 ks. Several crystallized particles were observed on the surface of the deposition test pieces. The particles had compositions and crystal structures which depended on both the composition of deposition test pieces and the concentration of iron and manganese in sodium. Only iron-rich particles having a polyhedral shape deposited on the iron surface. Two types of particles, iron-rich α-phase and γ-phase with nearly the same composition as stainless steel, were deposited on Type 304 stainless steel. A Ni-Mn alloy was deposited on the nickel surface in the case of a higher concentration of manganese in sodium. On the other hand, for a lower manganese concentration, a Fe-Ni alloy was precipitated on the nickel surface. Particles deposited on nickel had a γ-phase crystal structure similar to the deposition test piece of nickel. Hence, the deposition process can be explained as follows: Corrosion products in liquid sodium were deposited on the metal surface by forming a metal alloy selectively with elements of the metal surface. (author)

  3. Effect of Bleaching on Color Change and Surface Topography of Composite Restorations

    OpenAIRE

    Pruthi, Gunjan; Jain, Veena; Kandpal, H. C.; Mathur, Vijay Prakash; Shah, Naseem

    2010-01-01

    This study was conducted to determine the effect of 15% carbamide peroxide bleaching agent on color change and surface topography of different composite veneering materials (Filtek Z350 (3M ESPE), Esthet X (Dentsply India), and Admira (Voco, Germany). Methods. 30 samples were fabricated for evaluation of color change using CIELAB color system and Gonioreflectometer (GK 311/M, ZEISS). 45 disc-shaped specimens were made for evaluation of surface topography after bleaching (Nupro White Gold; Den...

  4. Mapping the Diffusion Potential of a Reconstructed Au(111) Surface at Nanometer Scale with 2D Molecular Gas

    International Nuclear Information System (INIS)

    Yan Shi-Chao; Xie Nan; Gong Hui-Qi; Guo Yang; Shan Xin-Yan; Lu Xing-Hua; Sun Qian

    2012-01-01

    The adsorption and diffusion behaviors of benzene molecules on an Au(111) surface are investigated by low-temperature scanning tunneling microscopy. A herringbone surface reconstruction of the Au(111) surface is imaged with atomic resolution, and significantly different behaviors are observed for benzene molecules adsorbed on step edges and terraces. The electric field induced modification in the molecular diffusion potential is revealed with a 2D molecular gas model, and a new method is developed to map the diffusion potential over the reconstructed Au(111) surface at the nanometer scale. (condensed matter: structure, mechanical and thermal properties)

  5. Multifractal and Singularity Maps of soil surface moisture distribution derived from 2D image analysis.

    Science.gov (United States)

    Cumbrera, Ramiro; Millán, Humberto; Martín-Sotoca, Juan Jose; Pérez Soto, Luis; Sanchez, Maria Elena; Tarquis, Ana Maria

    2016-04-01

    methods for mapping geochemical anomalies caused by buried sources and for predicting undiscovered mineral deposits in covered areas. Journal of Geochemical Exploration, 122, 55-70. Cumbrera, R., Ana M. Tarquis, Gabriel Gascó, Humberto Millán (2012) Fractal scaling of apparent soil moisture estimated from vertical planes of Vertisol pit images. Journal of Hydrology (452-453), 205-212. Martin Sotoca; J.J. Antonio Saa-Requejo, Juan Grau and Ana M. Tarquis (2016). Segmentation of singularity maps in the context of soil porosity. Geophysical Research Abstracts, 18, EGU2016-11402. Millán, H., Cumbrera, R. and Ana M. Tarquis (2016) Multifractal and Levy-stable statistics of soil surface moisture distribution derived from 2D image analysis. Applied Mathematical Modelling, 40(3), 2384-2395.

  6. A surface plasmon resonance assay for characterisation and epitope mapping of anti-GLP-1 antibodies.

    Science.gov (United States)

    Thomsen, Lasse; Gurevich, Leonid

    2018-04-19

    The incretin hormone glucagon-like peptide-1 (GLP-1) has been subject to substantial pharmaceutical research regarding the treatment of type 2 diabetes mellitus. However, quantification of GLP-1 levels remains complicated due to the low circulation concentration and concurrent existence of numerous metabolites, homologous peptides, and potentially introduced GLP-1 receptor agonists. Surface plasmon resonance (SPR) facilitates real-time monitoring allowing a more detailed characterisation of the interaction compared with conventional enzyme-linked immunosorbent assays (ELISA). In this paper, we describe the development of the first SPR assays for characterisation of anti-GLP-1 antibodies for ELISA purposes. Binding responses were obtained on covalently immobilised anti-GLP-1 antibodies at 12°C, 25°C, and 40°C and fitted to a biomolecular (1:1) interaction model showing association rates of 1.01 × 10 3 to 4.54 × 10 3  M -1  s -1 and dissociation rates of 3.56 × 10 -5 to 1.56 × 10 -3  s -1 leading to affinities of 35.2 to 344 nM, depending on the temperature. Determination of thermodynamic properties revealed an enthalpy driven interaction (ΔH polar amino acids (ΔC p  < 0). Pair-wise epitope mapping was performed on captured anti-GLP-1 antibodies followed by subsequent interaction with GLP-1 (7-36) and other anti-GLP-1 antibodies. A global evaluation of every binding response led to an epitope map elucidating the potential of various anti-GLP-1 antibody pairs for sandwich ELISA and hence pinpointing the optimal antibody combinations. The SPR assays proved capable of providing vital information for ELISA development endorsing it as a useful optimisation tool. Copyright © 2018 John Wiley & Sons, Ltd.

  7. Three-dimensional mapping of the local interstellar medium with composite data

    Science.gov (United States)

    Capitanio, L.; Lallement, R.; Vergely, J. L.; Elyajouri, M.; Monreal-Ibero, A.

    2017-10-01

    Context. Three-dimensional maps of the Galactic interstellar medium are general astrophysical tools. Reddening maps may be based on the inversion of color excess measurements for individual target stars or on statistical methods using stellar surveys. Three-dimensional maps based on diffuse interstellar bands (DIBs) have also been produced. All methods benefit from the advent of massive surveys and may benefit from Gaia data. Aims: All of the various methods and databases have their own advantages and limitations. Here we present a first attempt to combine different datasets and methods to improve the local maps. Methods: We first updated our previous local dust maps based on a regularized Bayesian inversion of individual color excess data by replacing Hipparcos or photometric distances with Gaia Data Release 1 values when available. Secondly, we complemented this database with a series of ≃5000 color excess values estimated from the strength of the λ15273 DIB toward stars possessing a Gaia parallax. The DIB strengths were extracted from SDSS/APOGEE spectra. Third, we computed a low-resolution map based on a grid of Pan-STARRS reddening measurements by means of a new hierarchical technique and used this map as the prior distribution during the inversion of the two other datasets. Results: The use of Gaia parallaxes introduces significant changes in some areas and globally increases the compactness of the structures. Additional DIB-based data make it possible to assign distances to clouds located behind closer opaque structures and do not introduce contradictory information for the close structures. A more realistic prior distribution instead of a plane-parallel homogeneous distribution helps better define the structures. We validated the results through comparisons with other maps and with soft X-ray data. Conclusions: Our study demonstrates that the combination of various tracers is a potential tool for more accurate maps. An online tool makes it possible to

  8. Methods of improvement in hardness of composite surface layer on cast steel

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2008-08-01

    Full Text Available The paper presents a method of usable properties of surface layers improvement of cast carbon steel 200–450, by put directly in founding process a composite surface layer on the basis of Fe-Cr-C alloy and next its remelting with use of welding technology TIG – Tungsten Inert Gas. Technology of composite surface layer guarantee mainly increase in hardness and abrasive wear resistance of cast steel castings on machine elements. This technology can be competition for generally applied welding technology (surfacing by welding and thermal spraying. However the results of studies show, that is possible to connection of both methods founding and welding of surface hardening of cast steel castings. In range of experimental plan was made test castings with composite surface layer, which next were remelted with energy 0,8 and 1,6 kJ/cm. Usability for industrial applications of test castings was estimated by criterion of hardness and abrasive wear resistance of type metal-mineral.

  9. Repair Bond Strength of Aged Resin Composite after Different Surface and Bonding Treatments

    Directory of Open Access Journals (Sweden)

    Michael Wendler

    2016-07-01

    Full Text Available The aim of this study was to compare the effect of different mechanical surface treatments and chemical bonding protocols on the tensile bond strength (TBS of aged composite. Bar specimens were produced using a nanohybrid resin composite and aged in distilled water for 30 days. Different surface treatments (diamond bur, phosphoric acid, silane, and sandblasting with Al2O3 or CoJet Sand, as well as bonding protocols (Primer/Adhesive were used prior to application of the repair composite. TBS of the specimens was measured and the results were analyzed using analysis of variance (ANOVA and the Student–Newman–Keuls test (α = 0.05. Mechanically treated surfaces were characterized under SEM and by profilometry. The effect of water aging on the degree of conversion was measured by means of FTIR-ATR spectroscopy. An important increase in the degree of conversion was observed after aging. No significant differences in TBS were observed among the mechanical surface treatments, despite variations in surface roughness profiles. Phosphoric acid etching significantly improved repair bond strength values. The cohesive TBS of the material was only reached using resin bonding agents. Application of an intermediate bonding system plays a key role in achieving reliable repair bond strengths, whereas the kind of mechanical surface treatment appears to play a secondary role.

  10. Evaluation of the surface structure of composite restorations in light of own pilot research

    Directory of Open Access Journals (Sweden)

    Chalas Renata

    2016-09-01

    Full Text Available Research on the dental restorative materials employed in remedying dental cavities has been conducted on many levels and areas, both with application of clinical and laboratory methods. One of the elements that determines whether the restoration may be degraded is the condition of its surface. The aim of the study was to assess the texture surface of composite restorations using a non-contact method of teeth models scanning. In this work, ten medium size cavities on the occlusal surfaces of molars in adult patients were prepared and restored with resin composite. Before undertaking the procedure and after the finishing and polishing of the restorations, impressions were taken and sent into the laboratory so as to prepare plaster casts. Every cast was then scanned utilizing the non-contact 3D surface measurement instrument so as to assess the texture surface of the restoration. The resulting three dimensional analyses of post-restoration models showed the correct marginal adaptation of resin composite dental material to the hard tooth structures and its smooth filling occlusal surface. Additional comparison of scans done before and after restoring the cavities allowed the calculating of differences in volume, mean and maximum heights. The applied method of analysis is thought to be helpful in the detailed evaluation of restoration dental material texture. Moreover, the enabled possibility of continuous observation is expedient for assessing the usefulness of the method in standard dental practice.

  11. Reducing Escherichia coli growth on a composite biomaterial by a surface immobilized antimicrobial peptide

    Energy Technology Data Exchange (ETDEWEB)

    Buckholtz, Gavin A.; Reger, Nina A. [Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282 (United States); Anderton, William D.; Schimoler, Patrick J. [Orthopaedic Biomechanics Research Laboratory, Allegheny General Hospital, Pittsburgh, PA 15212 (United States); Roudebush, Shana L.; Meng, Wilson S. [Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282 (United States); Miller, Mark C. [Orthopaedic Biomechanics Research Laboratory, Allegheny General Hospital, Pittsburgh, PA 15212 (United States); Gawalt, Ellen S., E-mail: gawalte@duq.edu [Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282 (United States); McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219 (United States)

    2016-08-01

    A new composite bioceramic consisting of calcium aluminum oxide (CaAlO) and hydroxyapatite (HA) was functionalized with the synthetic antimicrobial peptide Inverso-CysHHC10. CaAlO is a bioceramic that can be mold cast easily and quickly at room temperature. Improved functionality was previously achieved through surface reactions. Here, composites containing 0–5% HA (by mass) were prepared and the elastic modulus and modulus of rupture were mechanically similar to non-load bearing bone. The addition of hydroxyapatite resulted in increased osteoblast attachment (> 180%) and proliferation (> 140%) on all composites compared to 100% CaAlO. Antimicrobial peptide (AMP) immobilization was achieved using an interfacial alkene-thiol click reaction. The linked AMP persisted on the composite (> 99.6% after 24 h) and retained its activity against Escherichia coli based on N-phenylnaphthylamine uptake and bacterial turbidity tests. Overall, this simple scaffold system improves osteoblast activity and reduces bacterial activity. - Highlights: • Calcium aluminum oxide and hydroxyapatite were cast into a composite material. • Osteoblast attachment and proliferation were significantly increased on composites. • An active antimicrobial peptide was linked to and remained stable on the composite. • Bacterial turbidity and NPN uptake tests showed modified composites had an effect equal to a 10 μM Inverso-CysHHC10 solution. • Antimicrobial peptide linkage did not affect the increased osteoblast performance.

  12. Reducing Escherichia coli growth on a composite biomaterial by a surface immobilized antimicrobial peptide

    International Nuclear Information System (INIS)

    Buckholtz, Gavin A.; Reger, Nina A.; Anderton, William D.; Schimoler, Patrick J.; Roudebush, Shana L.; Meng, Wilson S.; Miller, Mark C.; Gawalt, Ellen S.

    2016-01-01

    A new composite bioceramic consisting of calcium aluminum oxide (CaAlO) and hydroxyapatite (HA) was functionalized with the synthetic antimicrobial peptide Inverso-CysHHC10. CaAlO is a bioceramic that can be mold cast easily and quickly at room temperature. Improved functionality was previously achieved through surface reactions. Here, composites containing 0–5% HA (by mass) were prepared and the elastic modulus and modulus of rupture were mechanically similar to non-load bearing bone. The addition of hydroxyapatite resulted in increased osteoblast attachment (> 180%) and proliferation (> 140%) on all composites compared to 100% CaAlO. Antimicrobial peptide (AMP) immobilization was achieved using an interfacial alkene-thiol click reaction. The linked AMP persisted on the composite (> 99.6% after 24 h) and retained its activity against Escherichia coli based on N-phenylnaphthylamine uptake and bacterial turbidity tests. Overall, this simple scaffold system improves osteoblast activity and reduces bacterial activity. - Highlights: • Calcium aluminum oxide and hydroxyapatite were cast into a composite material. • Osteoblast attachment and proliferation were significantly increased on composites. • An active antimicrobial peptide was linked to and remained stable on the composite. • Bacterial turbidity and NPN uptake tests showed modified composites had an effect equal to a 10 μM Inverso-CysHHC10 solution. • Antimicrobial peptide linkage did not affect the increased osteoblast performance.

  13. Effect of a surface sealant on the color stability of composite resins after immersion in staining solution.

    Science.gov (United States)

    Pedroso, Lauana Borges; Barreto, Luma Franciélle Cabreira; Miotti, Leonardo Lamberti; Nicoloso, Gabriel Ferreira; Durand, Leticia Brandão

    2016-01-01

    This study evaluated the influence of surface sealants on the color stability of 2 different composite resins after immersion in coffee. Four groups were created (n = 10): microhybrid composite, microhybrid with surface sealant, nanofilled composite, and nanofilled composite with surface sealant. Half of the specimens of each group were immersed in distilled water and half were immersed in coffee for 48 hours. Color was measured before and after immersion. Groups with surface sealants presented less color variation when compared with the groups without surface sealants. The nanofilled resin specimens presented the greatest color variation within the groups without sealant. The surface sealant positively influenced the color stability of composite resin specimens immersed in coffee. When surface sealant was not applied, the microhybrid specimens had better color stability than the nanofilled.

  14. Research note: Mapping spatial patterns in sewer age, material, and proximity to surface waterways to infer sewer leakage hotspots

    Science.gov (United States)

    Hopkins, Kristina G.; Bain, Daniel J.

    2018-01-01

    Identifying areas where deteriorating sewer infrastructure is in close proximity to surface waterways is needed to map likely connections between sewers and streams. We present a method to estimate sewer installation year and deterioration status using historical maps of the sewer network, parcel-scale property assessment data, and pipe material. Areas where streams were likely buried into the sewer system were mapped by intersecting the historical stream network derived from a 10-m resolution digital elevation model with sewer pipe locations. Potential sewer leakage hotspots were mapped by identifying where aging sewer pipes are in close proximity (50-m) to surface waterways. Results from Pittsburgh, Pennsylvania (USA), indicated 41% of the historical stream length was lost or buried and the potential interface between sewers and streams is great. The co-location of aging sewer infrastructure (>75 years old) near stream channels suggests that 42% of existing streams are located in areas with a high potential for sewer leakage if sewer infrastructure fails. Mapping the sewer-stream interface provides an approach to better understand areas were failing sewers may contribute a disproportional amount of nutrients and other pathogens to surface waterways.

  15. Mechanical Properties and Tribological Behavior of In Situ NbC/Fe Surface Composites

    Science.gov (United States)

    Cai, Xiaolong; Zhong, Lisheng; Xu, Yunhua

    2017-01-01

    The mechanical properties and tribological behavior of the niobium carbide (NbC)-reinforced gray cast iron surface composites prepared by in situ synthesis have been investigated. Composites are comprised of a thin compound layer and followed by a deep diffusion zone on the surface of gray cast iron. The graded distributions of the hardness and elastic modulus along the depth direction of the cross section of composites form in the ranges of 6.5-20.1 and 159.3-411.2 GPa, respectively. Meanwhile, dry wear tests for composites were implemented on pin-on-disk equipment at sliding speed of 14.7 × 10-2 m/s and under 5 or 20 N, respectively. The result indicates that tribological performances of composites are considerably dependent on the volume fraction and the grain size of the NbC as well as the mechanical properties of the matrices in different areas. The surface compound layer presents the lowest coefficient of friction and wear rate, and exhibits the highest wear resistance, in comparison with diffusion zone and substrate. Furthermore, the worn morphologies observed reveal the dominant wear mechanism is abrasive wear feature in compound layer and diffusion zone.

  16. Effects of wood fiber surface chemistry on strength of wood–plastic composites

    Energy Technology Data Exchange (ETDEWEB)

    Migneault, Sébastien, E-mail: sebastien.migneault@uqat.ca [University of Quebec in Abitibi-Temiscamingue (UQAT), 445 boulevard de l’Université, Rouyn-Noranda, Québec J9X 5E4 (Canada); Koubaa, Ahmed, E-mail: ahmed.koubaa@uqat.ca [UQAT (Canada); Perré, Patrick, E-mail: patrick.perre@ecp.fr [École centrale de Paris, Grande Voie des Vignes, F-92 295 Chatenay-Malabry Cedex (France); Riedl, Bernard, E-mail: Bernard.Riedl@sbf.ulaval.ca [Université Laval, 2425 rue de la Terrasse, Québec City, Québec G1V 0A6 (Canada)

    2015-07-15

    Highlights: • Infrared spectroscopy and X-ray photoelectron spectroscopy analyses showed variations of surface chemical characteristics according to fiber origin. • Surface chemical characteristics of fibers could partly explain the differences in mechanical properties of the wood–plastic composites. • Fibers with carbohydrate rich surface led to stronger wood–plastic composites because the coupling between the matrix and fibers using coupling agent is achieved with polar sites mostly available on carbohydrates. • Conversely, lignin or extractives rich surface do not have oxidized functions for the esterification reaction with coupling agent and thus led to wood–plastic composites with lower mechanical properties. • Other factors such as mechanical interlocking and fiber morphology interfere with the effects of fiber surface chemistry. - Abstract: Because wood–plastic composites (WPC) strength relies on fiber-matrix interaction at fiber surface, it is likely that fiber surface chemistry plays an important role in WPC strength development. The objective of the present study is to investigate the relationships between fiber surface chemical characteristics and WPC mechanical properties. Different fibers were selected and characterized for surface chemical characteristics using X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR). WPC samples were manufactured at 40% fiber content and with six different fibers. High density polyethylene was used as matrix and maleated polyethylene (MAPE) was used as compatibility agent. WPC samples were tested for mechanical properties and fiber-matrix interface was observed with scanning electron microscope. It was found WPC strength decreases as the amount of unoxidized carbon (assigned to lignin and extractives) measured with XPS on fiber surface increases. In the opposite case, WPC strength increases with increasing level of oxidized carbon (assigned to carbohydrates) on fiber surface. The same

  17. Effects of wood fiber surface chemistry on strength of wood–plastic composites

    International Nuclear Information System (INIS)

    Migneault, Sébastien; Koubaa, Ahmed; Perré, Patrick; Riedl, Bernard

    2015-01-01

    Highlights: • Infrared spectroscopy and X-ray photoelectron spectroscopy analyses showed variations of surface chemical characteristics according to fiber origin. • Surface chemical characteristics of fibers could partly explain the differences in mechanical properties of the wood–plastic composites. • Fibers with carbohydrate rich surface led to stronger wood–plastic composites because the coupling between the matrix and fibers using coupling agent is achieved with polar sites mostly available on carbohydrates. • Conversely, lignin or extractives rich surface do not have oxidized functions for the esterification reaction with coupling agent and thus led to wood–plastic composites with lower mechanical properties. • Other factors such as mechanical interlocking and fiber morphology interfere with the effects of fiber surface chemistry. - Abstract: Because wood–plastic composites (WPC) strength relies on fiber-matrix interaction at fiber surface, it is likely that fiber surface chemistry plays an important role in WPC strength development. The objective of the present study is to investigate the relationships between fiber surface chemical characteristics and WPC mechanical properties. Different fibers were selected and characterized for surface chemical characteristics using X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR). WPC samples were manufactured at 40% fiber content and with six different fibers. High density polyethylene was used as matrix and maleated polyethylene (MAPE) was used as compatibility agent. WPC samples were tested for mechanical properties and fiber-matrix interface was observed with scanning electron microscope. It was found WPC strength decreases as the amount of unoxidized carbon (assigned to lignin and extractives) measured with XPS on fiber surface increases. In the opposite case, WPC strength increases with increasing level of oxidized carbon (assigned to carbohydrates) on fiber surface. The same

  18. The impact of climate and composition on playa surface roughness: Investigation of atmospheric mineral dust emission mechanisms

    Science.gov (United States)

    Tollerud, H. J.; Fantle, M. S.

    2011-12-01

    there were no active processes during the summers that changed surface roughness. Images from NASA's MODIS instrument (1640 nm, band 6) delineate winter flooding on the playa. Areas of water in the winter tend to be smoother in the summer. In particular, a smooth area of the play in summer 2010 aligns very closely with ponded water in February 2010. This indicates that standing water disrupts the playa surface, reducing roughness. We also compared the distribution of surface roughness across the playa to playa composition. X-ray diffraction (XRD) of samples from the Black Rock Desert demonstrates that the playa surface is composed of approximately 30% quartz, 45% clays, 10% calcite, and 5% halite. Calcite and halite concentrations vary significantly between samples. We produced a map of calcite concentration in the Black Rock Desert based on hyperspectral data from NASA's EO-1 Hyperion instrument. We find that calcite concentrations are higher in smooth areas that have been inundated by water. Without an understanding of the surface processes associated with dust emission, it is difficult to model atmospheric dust, especially in the past or future when there is much less data for an empirical dust model.

  19. Universal composition-structure-property maps for natural and biomimetic platelet-matrix composites and stacked heterostructures.

    Science.gov (United States)

    Sakhavand, Navid; Shahsavari, Rouzbeh

    2015-03-16

    Many natural and biomimetic platelet-matrix composites--such as nacre, silk, and clay-polymer-exhibit a remarkable balance of strength, toughness and/or stiffness, which call for a universal measure to quantify this outstanding feature given the structure and material characteristics of the constituents. Analogously, there is an urgent need to quantify the mechanics of emerging electronic and photonic systems such as stacked heterostructures. Here we report the development of a unified framework to construct universal composition-structure-property diagrams that decode the interplay between various geometries and inherent material features in both platelet-matrix composites and stacked heterostructures. We study the effects of elastic and elastic-perfectly plastic matrices, overlap offset ratio and the competing mechanisms of platelet versus matrix failures. Validated by several 3D-printed specimens and a wide range of natural and synthetic materials across scales, the proposed universally valid diagrams have important implications for science-based engineering of numerous platelet-matrix composites and stacked heterostructures.

  20. Color Shaded-Relief and Surface-Classification Maps of the Fish Creek Area, Harrison Bay Quadrangle, Northern Alaska

    Science.gov (United States)

    Mars, John L.; Garrity, Christopher P.; Houseknecht, David W.; Amoroso, Lee; Meares, Donald C.

    2007-01-01

    Introduction The northeastern part of the National Petroleum Reserve in Alaska (NPRA) has become an area of active petroleum exploration during the past five years. Recent leasing and exploration drilling in the NPRA requires the U.S. Bureau of Land Management (BLM) to manage and monitor a variety of surface activities that include seismic surveying, exploration drilling, oil-field development drilling, construction of oil-production facilities, and construction of pipelines and access roads. BLM evaluates a variety of permit applications, environmental impact studies, and other documents that require rapid compilation and analysis of data pertaining to surface and subsurface geology, hydrology, and biology. In addition, BLM must monitor these activities and assess their impacts on the natural environment. Timely and accurate completion of these land-management tasks requires elevation, hydrologic, geologic, petroleum-activity, and cadastral data, all integrated in digital formats at a higher resolution than is currently available in nondigital (paper) formats. To support these land-management tasks, a series of maps was generated from remotely sensed data in an area of high petroleum-industry activity (fig. 1). The maps cover an area from approximately latitude 70?00' N. to 70?30' N. and from longitude 151?00' W. to 153?10' W. The area includes the Alpine oil field in the east, the Husky Inigok exploration well (site of a landing strip) in the west, many of the exploration wells drilled in NPRA since 2000, and the route of a proposed pipeline to carry oil from discovery wells in NPRA to the Alpine oil field. This map area is referred to as the 'Fish Creek area' after a creek that flows through the region. The map series includes (1) a color shaded-relief map based on 5-m-resolution data (sheet 1), (2) a surface-classification map based on 30-m-resolution data (sheet 2), and (3) a 5-m-resolution shaded relief-surface classification map that combines the shaded

  1. Effects of rare earth oxide additive on surface and tribological properties of polyimide composites

    Science.gov (United States)

    Pan, Zihe; Wang, Tianchang; Chen, Li; Idziak, Stefan; Huang, Zhaohui; Zhao, Boxin

    2017-09-01

    Rare earth oxide La2O3 microparticles-reinforced polyimide (PI) composites (La-PI-Cs) were fabricated, aiming to improve the tribological property of PI. Surface roughness, surface composition, bulk structure, friction force (Ff) and coefficient of friction (COF) at macro/micro preload, and anti-wear performances of La-PI-Cs were studied and compared with neat PI. With La2O3 microparticles, La-PI-Cs showed larger surface roughness, lower surface energy, and higher hydrophobicity than neat PI, and displayed beneficial layered structure different from the compact structure of PI. Owing to these advantages, La-PI-Cs were found to show a 70% reduction in Ff and COF, and a 30% reduction in wear rate, indicating significantly lowered friction and enhanced anti-wear properties after adding La2O3 microparticles. Our research findings demonstrated an easy and low cost method to fabricate polymer composites with low friction and high wear resistance, and help meet the demanding of polymer composites with high tribological performances in broaden applications.

  2. Surface characterization of weathered wood-plastic composites produced from modified wood flour

    Science.gov (United States)

    James S. Fabiyi; Armando G. McDonald; Nicole M. Stark

    2007-01-01

    The effects of weathering on the surface properties of wood-plastic composites (WPC) were examined. High-density polyethylene (HDPE) based WPCs made from modified wood flour (untreated, extractives free, and holocellulose (delignified) fibers) were subjected to accelerated (xenon-arc) weathering. Colorimetry and Fourier-transform infrared spectroscopy were employed to...

  3. Influence of mechanical and chemical degradation on surface gloss of resin composite materials

    NARCIS (Netherlands)

    Ardu, S.; Braut, V.; Uhac, I.; Benbachir, N.; Feilzer, A.J.; Krejci, I.

    2009-01-01

    Purpose: To determine the changes in surface gloss of different composite materials after simulation of mechanical and chemical aging mechanisms. Methods: 36 specimens were fabricated for each material and polished with 120-, 220-, 500-, 1200-, 2400- and 4000- grit SiC abrasive paper, respectively.

  4. Surface Modified Characteristics of the Tetracalcium Phosphate as Light-Cured Composite Resin Fillers

    Directory of Open Access Journals (Sweden)

    Wen-Cheng Chen

    2014-01-01

    Full Text Available The objectives of this study are to characterize the properties of light-cured composite resins that are reinforced with whisker surface-modified particles of tetracalcium phosphate (TTCP and to investigate the influence of thermal cycling on the reinforced composites properties. The characteristics of ultimate diametral tensile strength (DTS, moduli, pH values, and fracture surfaces of the samples with different amounts of surface-modified TTCP (30%–60% were determined before and after thermal cycling between 5°C and 55°C in deionized water for 600 cycles. The trends of all groups were ductile prior to thermal cycling and the moduli of all groups increased after thermal cycling. The ductile property of the control group without filler was not significantly affected. Larger amounts of fillers caused the particles to aggregate, subsequently decreasing the resin’s ability to disperse external forces and leading to brittleness after thermal cycling. Therefore, the trend of composite resins with larger amounts of filler would become more brittle and exhibited higher moduli after thermal cycling. This developed composite resin with surface modified-TTCP fillers has the potential to be successful dental restorative materials.

  5. Effects of different surface treatments on bond strength of an indirect composite to bovine dentin

    Directory of Open Access Journals (Sweden)

    Laiza Tatiana Poskus

    2015-01-01

    Conclusions: Sandblasting was a safe surface treatment for the indirect composite, increasing the BS values. Hydrofluoric acid applied after sandblasting damaged the BS values and should not be recommended while ethanol and H2O2, when applied after sandblasting, were effective in increasing BS values.

  6. Comparison of different finishing/polishing systems on surface roughness and gloss of resin composites.

    Science.gov (United States)

    Antonson, Sibel A; Yazici, A Rüya; Kilinc, Evren; Antonson, Donald E; Hardigan, Patrick C

    2011-07-01

    The aim of this study was to compare four finishing/polishing systems (F/P) on surface roughness and gloss of different resin composites. A total of 40 disc samples (15 mm × 3 mm) were prepared from a nanofill - Filtek Supreme Plus (FS) and a micro-hybrid resin composite - Esthet-X (EX). Following 24h storage in 37°C water, the top surfaces of each sample were roughened using 120-grit sandpaper. Baseline measurements of surface roughness (Ra, μm) and gloss were recorded. Each composite group was divided into four F/P disk groups: Astropol[AP], Enhance/PoGo[EP], Sof-Lex[SL], and an experimental disk system, EXL-695[EXL] (n=5). The same operator finished/polished all samples. One sample from each group was evaluated under SEM. Another blinded-operator conducted postoperative measurements. Results were analysed by two-way ANOVA, two interactive MANOVA and Tukey's t-test (p0.01). In gloss, FS composite with the EXL-695 system provided a significantly higher gloss (pgloss (pgloss. SEM evaluations revealed that the EX surface contained more air pockets but F/P systems were compatible. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Surface Roughness of Composite Resins after Simulated Toothbrushing with Different Dentifrices.

    Science.gov (United States)

    Monteiro, Bruna; Spohr, Ana Maria

    2015-07-01

    The aim of the study was to evaluate, in vitro, the surface roughness of two composite resins submitted to simulated toothbrushing with three different dentifrices. Totally, 36 samples of Z350XT and 36 samples of Empress Direct were built and randomly divided into three groups (n = 12) according to the dentifrice used (Oral-B Pro-Health Whitening [OBW], Colgate Sensitive Pro-Relief [CS], Colgate Total Clean Mint 12 [CT12]). The samples were submitted to 5,000, 10,000 or 20,000 cycles of simulated toothbrushing. After each simulated period, the surface roughness of the samples was measured using a roughness tester. According to three-way analysis of variance, dentifrice (P = 0.044) and brushing time (P = 0.000) were significant. The composite resin was not significant (P = 0.381) and the interaction among the factors was not significant (P > 0.05). The mean values of the surface roughness (µm) followed by the same letter represent no statistical difference by Tukey's post-hoc test (P composite resins. The dentifrice OBW caused a higher surface roughness in both composite resins.

  8. Oxidation behaviour of cast aluminium matrix composites with Ce surface coatings

    International Nuclear Information System (INIS)

    Pardo, A.; Merino, M.C.; Arrabal, R.; Feliu, S.; Viejo, F.

    2007-01-01

    The oxidation behaviour of SiC-reinforced aluminium matrix composites (A3xx.x/SiCp) has been studied after Ce-based treatments. Kinetics data of oxidation process were obtained from gravimetric tests performed at different temperatures (350, 425 and 500 o C). The nature of the oxidation layer was analyzed by scanning electron and atomic force microscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy and X-ray diffraction. The extent of oxidation degradation in untreated composites was preferentially localized in matrix/SiCp interfaces favouring the MgO formation. Ce coatings favoured a uniform oxidation of the composite surface with MgAl 2 O 4 spinel formation. This oxide increased the surface hardness of the materials

  9. Surface modification and micromechanical properties of jute fiber mat reinforced polypropylene composites

    Directory of Open Access Journals (Sweden)

    2007-05-01

    Full Text Available A new treating method using sodium hydroxide (NaOH and Maleic anhydride-grafted polypropylene (MPP emulsion was introduced to treat jute fiber mat in order to enhance the performance of jute/polypropylene (PP composite prepared by film stacking method. The surface modifications of jute fiber mat have been found to be very effective in improving the fiber-matrix adhesion. It was shown that treatments changed not only the surface topography but also the distribution of diameter and strength for the jute fibers, which was analyzed by using a two-parameter Weibull distribution model. Consequently, the interfacial shear strength, flexural and tensile strength of the composites all increased, but the impact strength decreased slightly. These results have demonstrated a new approach to use natural materials to enhance the mechanical performances of composites.

  10. Ion beam modifications of near-surface compositions in ternary alloys

    International Nuclear Information System (INIS)

    Lam, N.Q.; Tang, S.; Yacout, A.M.; Rehn, L.E.; Stubbins, J.F.

    1990-11-01

    Changes in the surface and subsurface compositions of ternary alloys during elevated-temperature sputtering with inert-gas ions were investigated. Theoretically, a comprehensive kinetic model which includes all the basic processes, such as preferential sputtering, displacement mixing, Gibbsian segregation, radiation-enhanced diffusion and radiation-induced segregation, was developed. This phenomenological approach enabled to predict the effects of each individual process or of a combination of processes on the compositional modification in model alloys. Experimentally, measurements of compositional changes at the surface of a Ag-40at%Au -- 20at%Cu alloy during 3-keV Ne + bombardment at various temperatures were made, using ion scattering spectroscopy. These measurements were interpreted on the basis of the results of theoretical modeling. 8 refs., 2 figs

  11. Toothbrushing alters the surface roughness and gloss of composite resin CAD/CAM blocks.

    Science.gov (United States)

    Kamonkhantikul, Krid; Arksornnukit, Mansuang; Lauvahutanon, Sasipin; Takahashi, Hidekazu

    2016-01-01

    This study investigated the surface roughness and gloss of composite resin CAD/CAM blocks after toothbrushing. Five composite resin blocks (Block HC, Cerasmart, Gradia Block, KZR-CAD Hybrid Resin Block, and Lava Ultimate), one hybrid ceramic (Vita Enamic), one feldspar ceramic (Vitablocs Mark II), one PMMA block (Telio CAD), and one conventional composite resin (Filtek Z350 XT) were evaluated. Surface roughness (Ra) and gloss were determined for each group of materials (n=6) after silicon carbide paper (P4000) grinding, 10k, 20k, and 40k toothbrushing cycles. One-way repeated measures ANOVA indicated significant differences in the Ra and gloss of each material except for the Ra of GRA. After 40k toothbrushing cycles, the Ra of BLO and TEL showed significant increases, while CER, KZR, ULT, and Z350 showed significant decreases. GRA, ENA, and VIT maintained their Ra. All of the materials tested, except CER, demonstrated significant decreases in gloss after 40k toothbrushing cycles.

  12. X-ray photoelectron spectroscopic analysis of rice kernels and flours: Measurement of surface chemical composition.

    Science.gov (United States)

    Nawaz, Malik A; Gaiani, Claire; Fukai, Shu; Bhandari, Bhesh

    2016-12-01

    The objectives of this study were to evaluate the ability of X-ray photoelectron spectroscopy (XPS) to differentiate rice macromolecules and to calculate the surface composition of rice kernels and flours. The uncooked kernels and flours surface composition of the two selected rice varieties, Thadokkham-11 (TDK11) and Doongara (DG) demonstrated an over-expression of lipids and proteins and an under-expression of starch compared to the bulk composition. The results of the study showed that XPS was able to differentiate rice polysaccharides (mainly starch), proteins and lipids in uncooked rice kernels and flours. Nevertheless, it was unable to distinguish components in cooked rice samples possibly due to complex interactions between gelatinized starch, denatured proteins and lipids. High resolution imaging methods (Scanning Electron Microscopy and Confocal Laser Scanning Microscopy) were employed to obtain complementary information about the properties and location of starch, proteins and lipids in rice kernels and flours. Copyright © 2016. Published by Elsevier Ltd.

  13. Melting of the Primitive Mercurian Mantle, Insights into the Origin of Its Surface Composition

    Science.gov (United States)

    Boujibar, A.; Righter, K.; Rapp, J. F.; Ross, D. K.; Pando, K. M.; Danielson, L. R.; Fontaine, E.

    2016-01-01

    Recent findings of the MESSENGER mission on Mercury have brought new evidence for its reducing nature, widespread volcanism and surface compositional heteregeneity. MESSENGER also provided major elemental ratios of its surface that can be used to infer large-scale differentiation processes and the thermal history of the planet. Mercury is known as being very reduced, with very low Fe-content and high S and alkali contents on its surface. Its bulk composition is therefore likely close to EH enstatite chondrites. In order to elucidate the origin of the chemical diversity of Mercury's surface, we determined the melting properties of EH enstatite chondrites, at pressures between 1 bar and 3 GPa and oxygen fugacity of IW-3 to IW-5, using piston-cylinder experiments, combined with a previous study on EH4 melting at 1 bar. We found that the presence of Ca-rich sulfide melts induces significant decrease of Ca-content in silicate melts at low pressure and low degree of melting (F). Also at pressures lower than 3 GPa, the SiO2-content decreases with F, while it increases at 3 GPa. This is likely due to the chemical composition of the bulk silicate which has a (Mg+Fe+Ca)/Si ratio very close to 1 and to the change from incongruent to congruent melting of enstatite. We then tested whether the various chemical compositions of Mercury's surface can result from mixing between two melting products of EH chondrites. We found that the majority of the geochemical provinces of Mercury's surface can be explained by mixing of two melts, with the exception of the High-Al plains that require an Al-rich source. Our findings indicate that Mercury's surface could have been produced by polybaric melting of a relatively primitive mantle.

  14. Adhesive bonding of resin composite to various titanium surfaces using different metal conditioners and a surface modification system

    Directory of Open Access Journals (Sweden)

    Hercules Jorge ALMILHATTI

    2013-12-01

    Full Text Available Objective: This study evaluated the effect of three metal conditioners on the shear bond strength (SBS of a prosthetic composite material to cpTi grade I having three surface treatments. Material and Methods: One hundred sixty eight rivet-shaped specimens (8.0x2.0 mm were cast and subjected to polishing (P or sandblasting with either 50 mm (50SB or 250 mm (250SB Al2O3. The metal conditioners Metal Photo Primer (MPP, Cesead II Opaque Primer (OP, Targis Link (TL, and one surface modification system Siloc (S, were applied to the specimen surfaces, which were covered with four 1-mm thick layers of resin composite. The resin layers were exposed to curing light for 90 s separately. Seven specimens from each experimental group were stored in water at 37ºC for 24 h while the other 7 specimens were subjected to 5,000 thermal cycles consisting of water baths at 4ºC and 60ºC (n=7. All specimens were subjected to SBS test (0.5 mm/min until failure occurred, and further 28 specimens were analyzed using scanning electron microscope (SEM and X-ray energy-dispersive spectroscopy (EDS. Data were analyzed by 3-way ANOVA followed by post-hoc Tukey's test (α=0.05. Results: On 50SB surfaces, OP groups showed higher SBS means than MPP (P<0.05, while no significant difference was found among OP, S, and TL groups. On 250SB surfaces, OP and TL groups exhibited higher SBS than MPP and S (P<0.05. No significant difference in SBS was found between OP and TL groups nor between MPP and S groups. The use of conditioners on 250SB surfaces resulted in higher SBS means than the use of the same products on 50SB surfaces (P<0.05. Conclusion: Sandblasting associated with the use of metal conditioners improves SBS of resin composites to cpTi.

  15. Neutron-induced gamma-ray spectroscopy: simulations for chemical mapping of planetary surfaces

    International Nuclear Information System (INIS)

    Brueckner, J.; Waenke, H.; Reedy, R.C.

    1986-01-01

    Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma-ray lines that can be measured by a gamma-ray spectrometer on board of an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which provides clues to its bulk composition and in turn to its origin and evolution. To investigate the gamma rays made by neutron interactions, thin targets were irradiated with neutrons having energies from 14 MeV to 0.025 eV. By means of foil activation technique the ratio of epithermal to thermal neutrons was determined to be similar to that in the Moon. Gamma rays emitted by the targets and the surrounding material were detected by a high-resolution germanium detector in the energy range of 0.1 to 8 MeV. Most of the gamma-ray lines that are expected to be used for planetary gamma-ray spectroscopy were found in the recorded spectra and the principal lines in these spectra are presented. 58 refs., 7 figs., 9 tabs

  16. Experimental study of surface quality and damage when drilling unidirectional CFRP composites

    Directory of Open Access Journals (Sweden)

    Eshetu D. Eneyew

    2014-10-01

    Full Text Available In this study, an experimental investigation on the drilling of unidirectional carbon fiber reinforced plastic (UD-CFRP composite was conducted using polycrystalline diamond (PCD tipped eight facet drill. The quality of the drilled hole surface was examined through surface roughness measurements and surface damage by scanning electron microscopy (SEM. It was found that fiber pullout occurred in two specific sectors relative to the angle between the cutting direction and the fiber orientation. The thrust force was highly influenced by the feed rate than the cutting speed and it shows a significant variation throughout the rotation of the drill.

  17. Global 30m 2000-2014 Surface Water Dynamics Map Derived from All Landsat 5, 7, and 8

    Science.gov (United States)

    Hudson, A.; Hansen, M.

    2015-12-01

    Water is critical for human life, agriculture, and ecosystems. A better understanding of where it is and how it is changing will enable better management of this valuable resource and guide protection of sensitive ecological areas. Global water maps have typically been representations of surface water at one given time. However, there is both seasonal and interannual variability: rivers meander, lakes disappear, floods arise. To address this ephemeral nature of water, in this study University of Maryland has developed a method that analyzes every Landsat 5, 7, and 8 scene from 1999-2015 to produce global seasonal maps (Winter, Spring, Summer, Fall) of surface water dynamics from 2000-2014. Each Landsat scene is automatically classified into land, water, cloud, haze, shadow, and snow via a decision tree algorithm. The land and water observations are aggregated per pixel into percent occurrence of water in a 3 year moving window for each meteorological season. These annual water percentages form a curve for each season that is discretized into a continuous 3 band RGB map. Frequency of water observation and type of surface water change (loss, gain, peak, or dip) is clearly seen through brightness and hue respectively. Additional data layers include: the year the change began, peak year, minimum year, and the year the change process ended. Currently these maps have been created for 18 1°x1° test tiles scattered around the world, and a portion of the September-November map over Bangladesh is shown below. The entire Landsat archive from 1999-2015 will be processed through a partnership with Google Earth Engine to complete the global product in the coming months. In areas where there is sufficient satellite data density (e.g. the United States), this project could be expanded to 1984-2015. This study provides both scientific researchers and the public an understandable, temporally rich, and globally consistent map showing surface water changes over time.

  18. Modelling of composition and stress profiles in low temperature surface engineered stainless steel

    DEFF Research Database (Denmark)

    Jespersen, Freja Nygaard; Hattel, Jesper Henri; Somers, Marcel A. J.

    2015-01-01

    temperature, time and gas composition is a prerequisite for targeted process optimization. A realistic model to simulate the developing case has to take the following influences on composition and stress into account: - a concentration dependent diffusion coefficient - trapping of nitrogen by chromium atoms...... stresses are introduced in the developing case, arising from the volume expansion that accompanies the dissolution of high interstitial contents in expanded austenite. Modelling of the composition and stress profiles developing during low temperature surface engineering from the processing parameters...... - the effect of residual stress on diffusive flux - the effect of residual stress on solubility of interstitials - plastic accommodation of residual stress. The effect of all these contributions on composition and stress profiles will be addressed....

  19. Large-Scale Mapping of Tree-Community Composition as a Surrogate of Forest Degradation in Bornean Tropical Rain Forests

    Directory of Open Access Journals (Sweden)

    Shogoro Fujiki

    2016-12-01

    Full Text Available Assessment of the progress of the Aichi Biodiversity Targets set by the Convention on Biological Diversity (CBD and the safeguarding of ecosystems from the perverse negative impacts caused by Reducing Emissions from Deforestation and Forest Degradation Plus (REDD+ requires the development of spatiotemporally robust and sensitive indicators of biodiversity and ecosystem health. Recently, it has been proposed that tree-community composition based on count-plot surveys could serve as a robust, sensitive, and cost-effective indicator for forest intactness in Bornean logged-over rain forests. In this study, we developed an algorithm to map tree-community composition across the entire landscape based on Landsat imagery. We targeted six forest management units (FMUs, each of which ranged from 50,000 to 100,000 ha in area, covering a broad geographic range spanning the most area of Borneo. Approximately fifty 20 m-radius circular plots were established in each FMU, and the differences in tree-community composition at a genus level among plots were examined for trees with diameter at breast height ≥10 cm using an ordination with non-metric multidimensional scaling (nMDS. Subsequently, we developed a linear regression model based on Landsat metrics (e.g., reflectance value, vegetation indices and textures to explain the nMDS axis-1 scores of the plots, and extrapolated the model to the landscape to establish a tree-community composition map in each FMU. The adjusted R2 values based on a cross-validation approach between the predicted and observed nMDS axis-1 scores indicated a close correlation, ranging from 0.54 to 0.69. Histograms of the frequency distributions of extrapolated nMDS axis-1 scores were derived from each map and used to quantitatively diagnose the forest intactness of the FMUs. Our study indicated that tree-community composition, which was reported as a robust indicator of forest intactness, could be mapped at a landscape level to

  20. Comparison of the impact of scaler material composition on polished titanium implant abutment surfaces.

    Science.gov (United States)

    Hasturk, Hatice; Nguyen, Daniel Huy; Sherzai, Homa; Song, Xiaoping; Soukos, Nikos; Bidlack, Felicitas B; Van Dyke, Thomas E

    2013-08-01

    The purpose of this study was to compare the impact of the removal of biofilm with hand scalers of different material composition on the surface of implant abutments by assessing the surface topography and residual plaque after scaling using scanning electron microscopy (SEM). Titanium implant analogs from 3 manufacturers (Straumann USA LLC, Andover, Maine, Nobel BioCare USA LLC, Yorba Linda, Cali, Astra Tech Implant Systems, Dentsply, Mölndal, Sweden) were mounted in stone in plastic vials individually with authentic prosthetic abutments. Plaque samples were collected from a healthy volunteer, inoculated into growth medium and incubated with the abutments anaerobically for 1 week. A blinded, calibrated hygienist performed scaling to remove the biofilm using 6 implant scalers (in triplicate), 1 scaler for 1 abutment. The abutments were mounted on an imaging stand and processed for SEM. Images were captured in 3 randomly designated areas of interest on each abutment. Analysis of the implant polished abutment surface and plaque area measurements were performed using ImageJ image analysis software. Surface alterations were characterized by the number, length, depth and the width of the scratches observed. Glass filled resin scalers resulted in significantly more and longer scratches on all 3 abutment types compared to other scalers, while unfilled resin scalers resulted in the least surface change (p abutments with regard to plaque removal. The impact of scalers on implant abutment surfaces varies between abutment types presumably due to different surface characteristics with no apparent advantage of one abutment type over the other with regard to resistance to surface damage. Unfilled resin was found consistently to be the least damaging to abutment surfaces, although all scalers of all compositions caused detectable surface changes to polished surfaces of implant abutments.

  1. Mid-infrared thermal imaging for an effective mapping of surface materials and sub-surface detachments in mural paintings: integration of thermography and thermal quasi-reflectography

    Science.gov (United States)

    Daffara, C.; Parisotto, S.; Mariotti, P. I.

    2015-06-01

    Cultural Heritage is discovering how precious is thermal analysis as a tool to improve the restoration, thanks to its ability to inspect hidden details. In this work a novel dual mode imaging approach, based on the integration of thermography and thermal quasi-reflectography (TQR) in the mid-IR is demonstrated for an effective mapping of surface materials and of sub-surface detachments in mural painting. The tool was validated through a unique application: the "Monocromo" by Leonardo da Vinci in Italy. The dual mode acquisition provided two spatially aligned dataset: the TQR image and the thermal sequence. Main steps of the workflow included: 1) TQR analysis to map surface features and 2) to estimate the emissivity; 3) projection of the TQR frame on reference orthophoto and TQR mosaicking; 4) thermography analysis to map detachments; 5) use TQR to solve spatial referencing and mosaicking for the thermal-processed frames. Referencing of thermal images in the visible is a difficult aspect of the thermography technique that the dual mode approach allows to solve in effective way. We finally obtained the TQR and the thermal maps spatially referenced to the mural painting, thus providing the restorer a valuable tool for the restoration of the detachments.

  2. Fast and Accurate Approaches for Large-Scale, Automated Mapping of Food Diaries on Food Composition Tables

    Directory of Open Access Journals (Sweden)

    Marc Lamarine

    2018-05-01

    Full Text Available Aim of Study: The use of weighed food diaries in nutritional studies provides a powerful method to quantify food and nutrient intakes. Yet, mapping these records onto food composition tables (FCTs is a challenging, time-consuming and error-prone process. Experts make this effort manually and no automation has been previously proposed. Our study aimed to assess automated approaches to map food items onto FCTs.Methods: We used food diaries (~170,000 records pertaining to 4,200 unique food items from the DiOGenes randomized clinical trial. We attempted to map these items onto six FCTs available from the EuroFIR resource. Two approaches were tested: the first was based solely on food name similarity (fuzzy matching. The second used a machine learning approach (C5.0 classifier combining both fuzzy matching and food energy. We tested mapping food items using their original names and also an English-translation. Top matching pairs were reviewed manually to derive performance metrics: precision (the percentage of correctly mapped items and recall (percentage of mapped items.Results: The simpler approach: fuzzy matching, provided very good performance. Under a relaxed threshold (score > 50%, this approach enabled to remap 99.49% of the items with a precision of 88.75%. With a slightly more stringent threshold (score > 63%, the precision could be significantly improved to 96.81% while keeping a recall rate > 95% (i.e., only 5% of the queried items would not be mapped. The machine learning approach did not lead to any improvements compared to the fuzzy matching. However, it could increase substantially the recall rate for food items without any clear equivalent in the FCTs (+7 and +20% when mapping items using their original or English-translated names. Our approaches have been implemented as R packages and are freely available from GitHub.Conclusion: This study is the first to provide automated approaches for large-scale food item mapping onto FCTs. We

  3. The influence of mouthrinses and simulated toothbrushing on the surface roughness of a nanofilled composite resin

    Directory of Open Access Journals (Sweden)

    Keico Graciela Sano Trauth

    2012-06-01

    Full Text Available The aim of this study was to determine the influence of mouthrinses on the surface roughness of a nanofilled composite resin after toothbrushing. One hundred nanofilled composite resin specimens were prepared and randomly distributed into two groups-brushed and non-brushed-and then assigned to five subgroups, according to the mouthrinse solutions (n = 10: Colgate Plax Fresh Mint, Oral B, Cepacol, Colgate Plax, and artificial saliva. Each sample was immersed in 20 mL of the mouthrinses for 1 minute, 5 days per week, twice a day, for a 3-week period. The control group used in the study was one in which the specimens were not subjected to brushing and remained only in artificial saliva. Toothbrushing was performed once a week for 1 minute, for 3 weeks. Surface roughness measurements (Ra were performed after the immersion period and toothbrushing, by means of a profilometer. Data were analyzed by two-way ANOVA and Tukey's test. Analysis revealed that the association between toothbrushing and Colgate Plax Fresh Mint produced the lowest surface roughness (p < 0.05. All other groups tested (Oral B, Cepacol, Colgate Plax, artificial saliva exhibited no statistically significant differences between surfaces, whether subjected to toothbrushing or not (p < 0.05. It was concluded that the surface roughness of the nanofilled composite resin tested can be influenced by the mouthrinse associated with toothbrushing.

  4. Global composites of surface wind speeds in tropical cyclones based on a 12 year scatterometer database

    Science.gov (United States)

    Klotz, Bradley W.; Jiang, Haiyan

    2016-10-01

    A 12 year global database of rain-corrected satellite scatterometer surface winds for tropical cyclones (TCs) is used to produce composites of TC surface wind speed distributions relative to vertical wind shear and storm motion directions in each TC-prone basin and various TC intensity stages. These composites corroborate ideas presented in earlier studies, where maxima are located right of motion in the Earth-relative framework. The entire TC surface wind asymmetry is down motion left for all basins and for lower strength TCs after removing the motion vector. Relative to the shear direction, the motion-removed composites indicate that the surface wind asymmetry is located down shear left for the outer region of all TCs, but for the inner-core region it varies from left of shear to down shear right for different basin and TC intensity groups. Quantification of the surface wind asymmetric structure in further stratifications is a necessary next step for this scatterometer data set.

  5. Role of particle size and composition in metal adsorption by solids deposited on urban road surfaces

    International Nuclear Information System (INIS)

    Gunawardana, Chandima; Egodawatta, Prasanna; Goonetilleke, Ashantha

    2014-01-01

    Despite common knowledge that the metal content adsorbed by fine particles is relatively higher compared to coarser particles, the reasons for this phenomenon have gained little research attention. The research study discussed in the paper investigated the variations in metal content for different particle sizes of solids associated with pollutant build-up on urban road surfaces. Data analysis confirmed that parameters favourable for metal adsorption to solids such as specific surface area, organic carbon content, effective cation exchange capacity and clay forming minerals content decrease with the increase in particle size. Furthermore, the mineralogical composition of solids was found to be the governing factor influencing the specific surface area and effective cation exchange capacity. There is high quartz content in particles >150 μm compared to particles <150 μm. As particle size reduces below 150 μm, the clay forming minerals content increases, providing favourable physical and chemical properties that influence adsorption. -- Highlights: • Physico-chemical parameters investigated in build-up samples from 32 road surfaces. • Mineralogical composition primarily governs the physico-chemical characteristics. • High clay forming mineral content in fine solids increases SSA and ECEC. • Characteristics influenced by quartz and amorphous content with particle size. • High quartz content in coarse particles contributes reduced metal adsorption. -- The mineralogical composition of solids is the governing factor influencing metal adsorption to solids in pollutant build-up on urban surfaces

  6. Towards Enhanced Performance Thin-film Composite Membranes via Surface Plasma Modification

    Science.gov (United States)

    Reis, Rackel; Dumée, Ludovic F.; Tardy, Blaise L.; Dagastine, Raymond; Orbell, John D.; Schutz, Jürg A.; Duke, Mikel C.

    2016-01-01

    Advancing the design of thin-film composite membrane surfaces is one of the most promising pathways to deal with treating varying water qualities and increase their long-term stability and permeability. Although plasma technologies have been explored for surface modification of bulk micro and ultrafiltration membrane materials, the modification of thin film composite membranes is yet to be systematically investigated. Here, the performance of commercial thin-film composite desalination membranes has been significantly enhanced by rapid and facile, low pressure, argon plasma activation. Pressure driven water desalination tests showed that at low power density, flux was improved by 22% without compromising salt rejection. Various plasma durations and excitation powers have been systematically evaluated to assess the impact of plasma glow reactions on the physico-chemical properties of these materials associated with permeability. With increasing power density, plasma treatment enhanced the hydrophilicity of the surfaces, where water contact angles decreasing by 70% were strongly correlated with increased negative charge and smooth uniform surface morphology. These results highlight a versatile chemical modification technique for post-treatment of commercial membrane products that provides uniform morphology and chemically altered surface properties. PMID:27363670

  7. Effect of surface morphology and densification on the infrared emissivity of C/SiC composites

    International Nuclear Information System (INIS)

    Wang, Fuyuan; Cheng, Laifei; Zhang, Qing; Zhang, Litong

    2014-01-01

    Highlights: • The cauliflower-like microstructure improved the infrared emissivity multiply. • The infrared emissivity decreased continually with the improving surface flatness. • The densification process boosted the infrared emissivity. - Abstract: The effects of surface morphology and densification on the infrared emissivity of 2D C/SiC composites were investigated in 6–16 μm from 1000 °C to 1600 °C. As the sample surface was polished, the reflection and scattering for the electromagnetic waves of thermal radiation were reduced, causing a sustained decrease in the infrared emissivity. The space-variant polarizations caused by the cauliflower-like microstructure were enervated in the smooth surface, which enhanced the reduction trendy in the infrared emissivity. In densification process, the increasing SiC content and the growing amount of the cauliflower-like microstructure on sample surface improved the infrared emissivity of C/SiC composites, while the decreasing porosity decreased it. Due to the greater positive effects on the thermal radiation during the densification process, the infrared emissivity of C/SiC composites increased successively with density

  8. Effect of surface morphology and densification on the infrared emissivity of C/SiC composites

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Fuyuan, E-mail: wangfy1986@gmail.com; Cheng, Laifei; Zhang, Qing, E-mail: zhangqing@nwpu.edu.cn; Zhang, Litong

    2014-09-15

    Highlights: • The cauliflower-like microstructure improved the infrared emissivity multiply. • The infrared emissivity decreased continually with the improving surface flatness. • The densification process boosted the infrared emissivity. - Abstract: The effects of surface morphology and densification on the infrared emissivity of 2D C/SiC composites were investigated in 6–16 μm from 1000 °C to 1600 °C. As the sample surface was polished, the reflection and scattering for the electromagnetic waves of thermal radiation were reduced, causing a sustained decrease in the infrared emissivity. The space-variant polarizations caused by the cauliflower-like microstructure were enervated in the smooth surface, which enhanced the reduction trendy in the infrared emissivity. In densification process, the increasing SiC content and the growing amount of the cauliflower-like microstructure on sample surface improved the infrared emissivity of C/SiC composites, while the decreasing porosity decreased it. Due to the greater positive effects on the thermal radiation during the densification process, the infrared emissivity of C/SiC composites increased successively with density.

  9. Comparison of different polishing methods on the surface roughness of microhybrid, microfill, and nanofill composite resins.

    Science.gov (United States)

    Moda, Mariana D; Godas, André Gustavo de L; Fernandes, Juliana C; Suzuki, Thaís Y U; Guedes, Ana Paula A; Briso, André L F; Bedran-Russo, Ana Karina; Dos Santos, Paulo H

    2018-02-01

    The aim of the present study was to evaluate the effect of different polishing methods on the surface roughness of resin-based composites subjected to a thermocycling procedure. A total of 192 specimens were divided into 24 groups, according to composite materials (Filtek Z250, Point 4, Renamel Nanofill, Filtek Supreme Plus, Renamel Microfill, and Premise) and finishing and polishing systems (Sof-Lex Pop On, Super Snap, Flexidisc, and Flexidisc+Enamelize). The specimens were subjected to thermocycling (5000 cycles). Filtek Supreme Plus showed the lowest surface roughness values before thermocycling. After thermocycling, Filtek Supreme Plus continued to have the lowest surface roughness, with a statistically-significant difference for the other materials. After thermocycling, there was no statistically-significant difference among all the polishing techniques studied. The thermocycling was concluded as being able to change composite resins' surface roughness, whereas different finishing and polishing methods did not result in surface roughness changes after thermocycling. © 2017 John Wiley & Sons Australia, Ltd.

  10. Self-organizing adaptive map: autonomous learning of curves and surfaces from point samples.

    Science.gov (United States)

    Piastra, Marco

    2013-05-01

    Competitive Hebbian Learning (CHL) (Martinetz, 1993) is a simple and elegant method for estimating the topology of a manifold from point samples. The method has been adopted in a number of self-organizing networks described in the literature and has given rise to related studies in the fields of geometry and computational topology. Recent results from these fields have shown that a faithful reconstruction can be obtained using the CHL method only for curves and surfaces. Within these limitations, these findings constitute a basis for defining a CHL-based, growing self-organizing network that produces a faithful reconstruction of an input manifold. The SOAM (Self-Organizing Adaptive Map) algorithm adapts its local structure autonomously in such a way that it can match the features of the manifold being learned. The adaptation process is driven by the defects arising when the network structure is inadequate, which cause a growth in the density of units. Regions of the network undergo a phase transition and change their behavior whenever a simple, local condition of topological regularity is met. The phase transition is eventually completed across the entire structure and the adaptation process terminates. In specific conditions, the structure thus obtained is homeomorphic to the input manifold. During the adaptation process, the network also has the capability to focus on the acquisition of input point samples in critical regions, with a substantial increase in efficiency. The behavior of the network has been assessed experimentally with typical data sets for surface reconstruction, including suboptimal conditions, e.g. with undersampling and noise. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Ion beam effects on the surface and near-surface composition of TaSi sub 2

    Energy Technology Data Exchange (ETDEWEB)

    Valeri, S.; Di Bona, A.; Ottaviani, G. (Dipt. di Fisica, Univ. di Modena (Italy)); Procop, M. (Zentralinstitut fuer Elektronenphysik, Berlin (Germany))

    1991-07-01

    Low-energy (0.7-4.5 keV) ion bombardment effects on polycrystalline TaSi{sub 2} at sputter steady state and in various intermediate steps have been investigated, in the temperature range up to 550degC, to determine the time and temperature dependence of the altered layer formation. This in turn enables a better knowledge of the synergistic effects of the processes mentioned above. At low temperatures (T{<=}410degC) the surface is silicon depleted, and the depletion is even more severe in the subsurface region up to a depth of several tens of angstroems; silicon preferential sputtering and radiation-enhanced segregation assisted by the displacement mixing-induced motion of atoms are assumed to be responsible for this composition profile, while thermally activated diffusion processes become operative above 410degC, reducing progressively the concentration gradient between the surface and the subsurface zone. The composition at different depths has been determined from Auger peaks for different kinetic energies, by varying the take-off angle and finally by sputter profiling at low in energy the high energy processed surfaces. Quantitative analysis has been performed by XPS and AES by using the elemental standard method. (orig.).

  12. Profilometric analysis of two composite resins' surface repolished after tooth brush abrasion with three polishing systems.

    Science.gov (United States)

    Uppal, Mudit; Ganesh, Arathi; Balagopal, Suresh; Kaur, Gurleen

    2013-07-01

    To evaluate the effect of three polishing protocols that could be implemented at recall on the surface roughness of two direct esthetic restorative materials. Specimens (n = 40) measuring 8 mm (length) × 5 mm (width) × 4 mm (height) were fabricated in an acrylic mold using two light-cured resin-based materials (microfilled composite and microhybrid composite). After photopolymerization, all specimens were finished and polished with one of three polishing protocols (Enhance, One Gloss, and Sof-Lex polishing systems). The average surface roughness of each treated specimen was determined using 3D optical profilometer. Next all specimens were brushed 60,000 times with nylon bristles at 7200 rpm using crosshead brushing device with equal parts of toothpaste and water used as abrasive medium. The surface roughness of each specimen was measured after brushing followed by repolishing with one of three polishing protocols, and then, the final surface roughness values were determined. The data were analyzed using one-way and two-factor analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD). Significant difference (P < 0.05) in surface roughness was observed. Simulated brushing following initial polishing procedure significantly roughened the surface of restorative material (P < 0.05). Polishing protocols can be used to restore a smooth surface on esthetic restorative materials following simulated tooth brushing.

  13. High Frequency Anodising of Aluminium-TiO2 Surface Composites

    DEFF Research Database (Denmark)

    Gudla, Visweswara Chakravarthy; Bordo, Kirill; Jensen, Flemming

    2015-01-01

    was also measured as a function of various anodising parameters. Anodic film growth, hardness, and total reflectance of the surface were found to be highly dependent on the anodising frequency and the anodic cycle potential. Longer exposure times to the anodising electrolyte at lower growth rates resulted......High frequency anodising of Al–TiO2 surface composites using pulse reverse pulse technique was investigated with an aim to understand the effect of the anodising parameters on the optical appearance, microstructure, hardness and growth rate of the anodic layer. Friction stir processing was employed...... to prepare the Al–TiO2 surface composites, which were anodised in a 20 wt.% sulphuric acid bath at 10 °C as a function of pulse frequency, pulse duty cycle, and anodic cycle voltage amplitudes. The optical appearance of the films was characterized and quantified using an integrating sphere-spectrometer setup...

  14. Multi-pollutant surface objective analyses and mapping of air quality health index over North America.

    Science.gov (United States)

    Robichaud, Alain; Ménard, Richard; Zaïtseva, Yulia; Anselmo, David

    2016-01-01

    Air quality, like weather, can affect everyone, but responses differ depending on the sensitivity and health condition of a given individual. To help protect exposed populations, many countries have put in place real-time air quality nowcasting and forecasting capabilities. We present in this paper an optimal combination of air quality measurements and model outputs and show that it leads to significant improvements in the spatial representativeness of air quality. The product is referred to as multi-pollutant surface objective analyses (MPSOAs). Moreover, based on MPSOA, a geographical mapping of the Canadian Air Quality Health Index (AQHI) is also presented which provides users (policy makers, public, air quality forecasters, and epidemiologists) with a more accurate picture of the health risk anytime and anywhere in Canada and the USA. Since pollutants can also behave as passive atmospheric tracers, they provide information about transport and dispersion and, hence, reveal synoptic and regional meteorological phenomena. MPSOA could also be used to build air pollution climatology, compute local and national trends in air quality, and detect systematic biases in numerical air quality (AQ) models. Finally, initializing AQ models at regular time intervals with MPSOA can produce more accurate air quality forecasts. It is for these reasons that the Canadian Meteorological Centre (CMC) in collaboration with the Air Quality Research Division (AQRD) of Environment Canada has recently implemented MPSOA in their daily operations.

  15. Mapping cellular hierarchy by single-cell analysis of the cell surface repertoire.

    Science.gov (United States)

    Guo, Guoji; Luc, Sidinh; Marco, Eugenio; Lin, Ta-Wei; Peng, Cong; Kerenyi, Marc A; Beyaz, Semir; Kim, Woojin; Xu, Jian; Das, Partha Pratim; Neff, Tobias; Zou, Keyong; Yuan, Guo-Cheng; Orkin, Stuart H

    2013-10-03

    Stem cell differentiation pathways are most often studied at the population level, whereas critical decisions are executed at the level of single cells. We have established a highly multiplexed, quantitative PCR assay to profile in an unbiased manner a panel of all commonly used cell surface markers (280 genes) from individual cells. With this method, we analyzed over 1,500 single cells throughout the mouse hematopoietic system and illustrate its utility for revealing important biological insights. The comprehensive single cell data set permits mapping of the mouse hematopoietic stem cell differentiation hierarchy by computational lineage progression analysis. Further profiling of 180 intracellular regulators enabled construction of a genetic network to assign the earliest differentiation event during hematopoietic lineage specification. Analysis of acute myeloid leukemia elicited by MLL-AF9 uncovered a distinct cellular hierarchy containing two independent self-renewing lineages with different clonal activities. The strategy has broad applicability in other cellular systems. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Project CONVERGE: Initial Results From the Mapping of Surface Currents in Palmer Deep

    Science.gov (United States)

    Statscewich, H.; Kohut, J. T.; Winsor, P.; Oliver, M. J.; Bernard, K. S.; Cimino, M. A.; Fraser, W.

    2016-02-01

    The Palmer Deep submarine canyon on the Western Antarctic Peninsula provides a conduit for upwelling of relatively warm, nutrient rich waters which enhance local primary production and support a food web productive enough to sustain a large top predator biomass. In an analysis of ten years of satellite-tagged penguins, Oliver et al. (2013) showed that circulation features associated with tidal flows may be a key driver of nearshore predator distributions. During diurnal tides, the penguins feed close to their breeding colonies and during semi-diurnal tides, the penguins make foraging trips to the more distant regions of Palmer Deep. It is hypothesized that convergent features act to concentrate primary producers and aggregate schools of krill that influence the behavior of predator species. The initial results from a six month deployment of a High Frequency Radar network in Palmer Deep are presented in an attempt to characterize and quantify convergent features. During a three month period from January through March 2015, we conducted in situ sampling consisting of multiple underwater glider deployments, small boat acoustic surveys of Antarctic krill, and penguin ARGOS-linked satellite telemetry and time-depth recorders (TDRs). The combination of real-time surface current maps with adaptive in situ sampling introduces High Frequency Radar to the Antarctic in a way that allows us to rigorously and efficiently test the influence of local tidal processes on top predator foraging ecology.

  17. Enhanced Boiling on Micro-Configured Composite Surfaces Under Microgravity Conditions

    Science.gov (United States)

    Zhang, Nengli; Chai, An-Ti

    1999-01-01

    In order to accommodate the growing thermal management needs of future space platforms, several two-phase active thermal control systems (ATCSs) have evolved and were included in the designs of space stations. Compared to the pumped single-phase liquid loops used in the conventional Space Transportation System and Spacelab, ATCSs offer significant benefits that may be realized by adopting a two-phase fluid-loop system. Alternately, dynamic power systems (DPSs), based on the Rankine cycle, seem inevitably to be required to supply the electrical power requirements of expanding space activities. Boiling heat transfer is one of the key technologies for both ATCSs and DPSs. Nucleate boiling near critical heat flux (CHF) can transport very large thermal loads with much smaller device size and much lower pumping power. However, boiling performance deteriorates in a reduced gravity environment and operation in the CHF regime is precarious because any slight overload will cause the heat transfer to suddenly move to the film boiling regime, which in turn, will result in burnout of the heat transfer surfaces. New materials, such as micro-configured metal-graphite composites, can provide a solution for boiling enhancement. It has been shown experimentally that this type of material manifests outstanding boiling heat transfer performance and their CHF is also extended to higher values. Due to the high thermal conductivity of graphite fiber (up to 1,200 W/m-K in the fiber direction), the composite surfaces are non-isothermal during the boiling process. The composite surfaces are believed to have a much wider safe operating region (a more uniform boiling curve in the CHF regime) because non-isothermal surfaces have been found to be less sensitive to variations of wall superheat in the CHF regime. The thermocapillary forces formed by the temperature difference between the fiber tips and the metal matrix play a more important role than the buoyancy in the bubble detachment, for the

  18. High-precision geologic mapping to evaluate the potential for seismic surface rupture at TA-55, Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Gardner, J.N.; Lavine, A.; Vaniman, D.; WoldeGabriel, G.

    1998-06-01

    In this report the authors document results of high-precision geologic mapping in the vicinity of TA-55 that has been done to identify parts of the southern portion of the Rendija Canyon Fault, or any other faults, with the potential for seismic surface rupture. To assess the potential for surface rupture at TA-55, an area of approximately 3 square miles that includes the Los Alamos County Landfill and Twomile, Mortandad, and Sandia Canyons has been mapped in detail. Map units are mostly cooling or flow units within the Tshirege Member (1.2 Ma) of the Bandelier Tuff. Stratigraphic markers that are useful for determining offsets in the map area include a distinct welding break at or near the cooling Unit 2-Unit 3 contact, and the Unit 3-Unit 4 contact. At the County Landfill the contact between the Tshirege Member of the Bandelier Tuff and overlying Quaternary alluvium has also been mapped. The mapping indicates that there is no faulting in the near-surface directly below TA-55, and that the closest fault is about 1500 feet west of the Plutonium Facility. Faulting is more abundant on the western edge of the map area, west of TA-48 in uppermost Mortandad Canyon, upper Sandia Canyon, and at the County Landfill. Measured vertical offsets on the faults range from 1 to 8 feet on mapped Bandelier Tuff contacts. Faulting exposed at the Los Alamos County Landfill has deformed a zone over 1000 feet wide, and has a net vertical down-to-the-west displacement of at least 15 feet in the Bandelier Tuff. Individual faults at the landfill have from less than 1 foot to greater than 15 feet of vertical offset on the Bandelier Tuff. Most faults in the landfill trend N-S, N20W, or N45E. Results of the mapping indicate that the Rendija Canyon Fault does not continue directly south to TA-55. At present, the authors have insufficient data to connect faulting they have mapped to areas of known faulting to the north or south of the study area

  19. Visualization of amino acid composition differences between processed protein from different animal species by self-organizing feature maps

    Directory of Open Access Journals (Sweden)

    Xingfan ZHOU,Zengling YANG,Longjian CHEN,Lujia HAN

    2016-06-01

    Full Text Available Amino acids are the dominant organic components of processed animal proteins, however there has been limited investigation of differences in their composition between various protein sources. Information on these differences will not only be helpful for their further utilization but also provide fundamental information for developing species-specific identification methods. In this study, self-organizing feature maps (SOFM were used to visualize amino acid composition of fish meal, and meat and bone meal (MBM produced from poultry, ruminants and swine. SOFM display the similarities and differences in amino acid composition between protein sources and effectively improve data transparency. Amino acid composition was shown to be useful for distinguishing fish meal from MBM due to their large concentration differences between glycine, lysine and proline. However, the amino acid composition of the three MBMs was quite similar. The SOFM results were consistent with those obtained by analysis of variance and principal component analysis but more straightforward. SOFM was shown to have a robust sample linkage capacity and to be able to act as a powerful means to link different sample for further data mining.

  20. Repair bond strength of composite resin to sandblasted and laser irradiated Y-TZP ceramic surfaces.

    Science.gov (United States)

    Kirmali, Omer; Barutcigil, Çağatay; Ozarslan, Mehmet Mustafa; Barutcigil, Kubilay; Harorlı, Osman Tolga

    2015-01-01

    This study investigated the effects of different surface treatments on the repair bond strength of yttrium-stabilized tetragonal zirconia polycrystalline ceramic (Y-TZP) zirconia to a composite resin. Sixty Y-TZP zirconia specimens were prepared and randomly divided into six groups (n = 10) as follows: Group 1, surface grinding with Cimara grinding bur (control); Group 2, sandblasted with 30 µm silica-coated alumina particles; Group 3, Nd:YAG laser irradiation; Group 4, Er,Cr:YSGG laser irradiation; Group 5, sandblasted + Nd:YAG laser irradiation; and Group 6, sandblasted + Er,Cr:YSGG laser irradiation. After surface treatments, the Cimara(®) System was selected for the repair method and applied to all specimens. A composite resin was built-up on each zirconia surface using a cylindrical mold (5 × 3 mm) and incrementally filled. The repair bond strength was measured with a universal test machine. Data were analyzed using a one-way ANOVA and a Tukey HSD test (p = 0.05). Surface topography after treatments were evaluated by a scanning electron microscope (SEM). Shear bond strength mean values ranged from 15.896 to 18.875 MPa. There was a statistically significant difference between group 3 and the control group (p < 0.05). Also, a significant increase in bond strength values was noted in group 6 (p < 0.05). All surface treatment methods enhanced the repair bond strength of the composite to zirconia; however, there were no significant differences between treatment methods. The results revealed that Nd:YAG laser irradiation along with the combination of sandblasting and Er,Cr:YSGG laser irradiation provided a significant increase in bond strength between the zirconia and composite resin. © Wiley Periodicals, Inc.

  1. Within-Class and Neighborhood Effects on the Relationship between Composite Urban Classes and Surface Temperature

    Directory of Open Access Journals (Sweden)

    Peleg Kremer

    2018-02-01

    Full Text Available Understanding the relationship between urban structure and ecological function—or environmental performance—is important for the planning of sustainable cities, and requires examination of how components in urban systems are organized. In this paper, we develop a Structure of Urban Landscape (STURLA classification, identifying common compositions of urban components using Berlin, Germany as a case study. We compute the surface temperature corresponding to each classification grid cell, and perform within-cell and neighborhood analysis for the most common composite classes in Berlin. We found that with-class composition and neighborhood composition as well as the interaction between them drive surface temperature. Our findings suggest that the spatial organization of urban components is important in determining the surface temperature and that specific combinations, such as low-rise buildings surrounded by neighborhood trees, or mid-rise buildings surrounded by high-rise buildings, compound to create a cooling effect. These findings are important for developing an understanding of how urban planning can harness structure-function relationships and improve urban sustainability.

  2. [Preparation and catalytic activity of surface-modification CNTs/TiO2 composite photocatalysts].

    Science.gov (United States)

    Wang, Huan-Ying; Li, Wen-Jun; Chang, Zhi-Dong; Zhou, Hua-Lei; Guo, Hui-Chao

    2011-09-01

    A novel kind of carbon nanotubes/titanium dioxide (CNTs/TiO2) composite photocatalyst was prepared by a modified sol-gel method in which the nanoscaled TiO2 particles were uniformly deposited on the CNTs modified with poly(vinyl pyrrolidone) (PVP). The composites were characterized by a range of analytical techniques including high resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results show the successful covering of the CNTs with PVP, forming core-shell structure. The nanoscaled TiO2 particles were uniformly deposited on the surface of CNTs reducing the bare CNTs which avoid losing the absorption and scattering of photons. The combination of CNTs and TiO2 particles imply the enhanced interactions between the CNTs and TiO2 interface which possibly becomes heterojunction. The composites become mesoporous crystalline TiO2 (anatase) clusters after annealing at 500 degrees C, and the surface area increases obviously. The photocatalytic activities of surface modification CNTs/TiO2 (smCNTs/TiO2) composites are extremely enhanced from the results of the photodegradation of methylene blue (MB).

  3. Organic composite-mediated surface coating of human acellular bone matrix with strontium.

    Science.gov (United States)

    Huang, Yi-Zhou; Wang, Jing-Jing; Huang, Yong-Can; Wu, Cheng-Guang; Zhang, Yi; Zhang, Chao-Liang; Bai, Lin; Xie, Hui-Qi; Li, Zhao-Yang; Deng, Li

    2018-03-01

    Acellular bone matrix (ACBM) provides an osteoconductive scaffold for bone repair, but its osteoinductivity is poor. Strontium (Sr) improves the osteoinductivity of bone implants. In this study, we developed an organic composite-mediated strontium coating strategy for ACBM scaffolds by using the ion chelating ability of carboxymethyl cellulose (CMC) and the surface adhesion ability of dopamine (DOPA). The organic coating composite, termed the CMC-DOPA-Sr composite, was synthesized under a mild condition, and its chemical structure and strontium ion chelating ability were then determined. After surface decoration, the physicochemical properties of the strontium-coated ACBM (ACBM-Sr) scaffolds were characterized, and their biocompatibility and osteoinductivity were determined in vitro and in vivo. The results showed that the CMC-DOPA-Sr composite facilitated strontium coating on the surface of ACBM scaffolds. The ACBM-Sr scaffolds possessed a sustained strontium ion release profile, exhibited good cytocompatibility, and enhanced the osteogenic differentiation of mesenchymal stem cells in vitro. Furthermore, the ACBM-Sr scaffolds showed good histocompatibility after subcutaneous implantation in nude mice. Taken together, this study provided a simple and mild strategy to realize strontium coating for ACBM scaffolds, which resulted in good biocompatibility and improved osteoinductivity. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Gloss and surface roughness produced by polishing kits on resin composites.

    Science.gov (United States)

    Sadidzadeh, Ramtin; Cakir, Deniz; Ramp, Lance C; Burgess, John O

    2010-08-01

    To compare in vitro the surface roughness (Ra) and gloss (G) produced by three conventional and one experimental polishing kits on four resin composites. 24 discs were prepared (d = 12 mm, t = 4 mm) for each resin composite: Filtek Supreme Plus Body/A2 (FSB), Yellow Translucent (FST), Heliomolar/A2 (HM), and EsthetX/A2 (EX) following the manufacturers' instructions. They were finished with 320 grit silicon carbide paper for 80 seconds each. Polishing systems: Sof-Lex, Enhance-Pogo, Astropol and Experimental Discs/EXL-695, were applied following manufacturers' instructions. Each specimen was ultrasonically cleaned with distilled water and dried. Gloss and Ra were measured with a small area glossmeter (Novo-curve) and non-contact profilometer (Proscan 2000) following ISO 4288, respectively. The results were evaluated by two-way ANOVA followed by separate one-way ANOVA and Tukey/Kramer test (P = 0.05). There was a significant interaction of surface roughness and gloss between the composites and polishing systems (P gloss was obtained for FSB composite polished with the Experimental kit. The experimental polishing system produced smoothest surfaces (P gloss (P < 0.05).

  5. Analysis of the Effect of Surface Modification on Polyimide Composites Coated with Erosion Resistant Materials

    Science.gov (United States)

    Ndalama, Tchinga; Hirschfeld, Deidre; Sutter, James K. (Technica