37 research outputs found

    Efficient, environmentally acceptable method for waterproofing insulation material

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    A process of waterproofing alumina-rich or silica-rich fibrous thermal insulation material, the process including the steps of: (a) providing an alumina-rich or a silica-rich fibrous material; (b) providing a waterproofing solution including: (1) a carrier solvent selected from the group consisting of aliphatic alcohols having from 1C to 6C, water, and mixtures thereof; and (2) an alkoxysilane defined by the formula R.sub.4-x -Si-(O-R').sub.x where x is 1-3 and R is selected from the group consisting of alkyl groups having from 1C to 10C, hydrogen, or fluorocarbon groups having from 1F to 15F; and where O-R' is an alkoxy group having from 1C to 5C, or a mixture of alkoxysilanes defined by the above formula R.sub.4-x -Si-(O-R').sub.x ; and optionally (3) modifiers including acids, such as acetic acid or nitric acid, or bases, such as ammonium hydroxide, RNH.sub.2, R.sub.2 NH, or R.sub.3 N, or MOH, where R is selected from the group consisting of alkyl groups having from 1C to 10C or hydrogen, and where M=Na, Li, or K; (c) contacting the fibrous material with the waterproofing solution for a sufficient amount of time to waterproof the fibrous material; and (d) curing the coated fibrous material to render it sufficiently waterproof. A chemical solution for waterproofing alumina-rich or silica-rich fibrous thermal insulation materials, the solution including: (a) a carrier solvent selected from the group consisting of aliphatic alcohols having from 1C to 6C, water, and mixtures thereof; and (b) an alkoxysilane defined by the formula R.sub.4-x -Si-(O-R').sub.x where x is 1-3 and R is selected from the group consisting of alkyl groups having from 1C to 10C, hydrogen, or fluorocarbon groups having from 1F to 15F; and where O-R' is an alkoxy group having from 1C to 5C, or a mixture of alkoxysilanes defined by the above formula R.sub.4-x -Si-(O-R').sub.x ; and optionally (c) modifiers including acids, such as acetic acid or nitric acid, or bases, such as ammonium hydroxide, RNH.sub.2, R.sub.2 NH, or R.sub.3 N, or MOH, where R is selected from the group consisting of alkyl groups having from 1C to 10C or hydrogen, and where M=Na, Li, or K

    An HST/WFPC Survey of Bright Young Clusters in M31. II. Photometry of Less Luminous Clusters in the Fields

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    We report on the properties of 89 low mass star clusters located in the vicinity of luminous young clusters (blue globulars) in the disk of M31. 82 of the clusters are newly detected. We have determined their integrated magnitudes and colors, based on a series of Hubble Space Telescope Wide Field/Planetary Camera 2 exposures in blue and red (HST filters F450W and F814W). The integrated apparent magnitudes range from F450W = 17.5 to 22.5, and the colors indicate a wide range of ages. Stellar color-magnitude diagrams for all clusters were obtained and those with bright enough stars were fit to theoretical isochrones to provide age estimates. The ages range from 12 Myr to >500 Myr. Reddenings, which average E(F450 - F814) = 0.59 with a dispersion of 0.21 magnitudes, were derived from the main sequence fitting for those clusters. Comparison of these ages and integrated colors with single population theoretical models with solar abundances suggests a color offset of 0.085 magnitudes at the ages tested. Estimated ages for the remaining clusters are based on their measured colors. The age-frequency diagram shows a steep decline of number with age, with a large decrease in number per age interval between the youngest and the oldest clusters detected.Comment: 20 pages, 9 figure

    Carbon Star Survey of Local Group Dwarf Galaxies. II. Pegasus, DDO 210 and Tucana

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    We present the latest results of our ongoing four filter photometric survey of C stars in Local Group dwarf irregular galaxies. Observations of the two low luminosity dwarf irregular galaxies, Pegasus and DDO 210, revealed respectively 40 and 3 C stars, assuming that the reddening of Pegasus is negligible. No C stars were identified in Tucana. Our observations permit the estimation of the CMD contamination by foreground M dwarf thus yielding reliable C/M ratios. Our R, I photometry of the C stars cannot be used to solve the extinction controversy toward Pegasus. The three C stars in DDO 210 are quite bright when compared to C star populations in dwarf galaxies. A larger fainter population in that galaxy seems however improbable. The statistics of C stars, currently on hand for dwarf galaxies, show a well-defined trend with the absolute magnitude of galaxies.Comment: 18 pages, 7 figures, 6 table

    The deep XMM-Newton Survey of M 31

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    Aims. M 31 has been completely imaged for the first time obtaining a luminosity lower limit ~10^35 erg s-1 in the 0.2-4.5 keV band. Our XMM-Newton EPIC survey combines archival observations with observations taken between June 2006 and February 2008. The main goal of the paper is a study of the X-ray source population of M 31. Methods. An X-ray catalogue of 1897 sources was created; 914 were detected for the first time. Source classification and identification were based on X-ray hardness ratios, spatial extent of the sources, and by cross correlating with catalogues in the X-ray, optical, infrared and radio wavelengths. We also analysed the long-term variability of the X-ray sources. Results. Fourteen of the 30 supersoft source candidates represent supersoft emission of optical novae. Many of the 25 supernova remnants (SNRs) and 31 SNR candidates lie within the 10 kpc dust ring and other star forming regions in M 31; this connection between SNRs and star forming regions implies that most of the remnants originate in type II supernovae. The brightest sources in X-rays in M 31 belong to the class of X-ray binaries (XRBs). Ten low mass XRBs (LMXBs) and 26 LMXB candidates were identified based on their temporal variability. In addition 36 LMXBs and 17 LMXB candidates were identified due to correlations with globular clusters and globular cluster candidates. From optical and X-ray colour-colour diagrams, possible high mass XRB (HMXB) candidates were selected. Two of these candidates have an X-ray spectrum as is expected for an HMXB containing a neutron star primary. Conclusions. While our survey has greatly improved our understanding of the X-ray source populations in M 31, at this point 65% of the sources can still only be classified as "hard" sources. Deeper observations in X-ray and at other wavelengths would help classify these sources. ABRIDGEDComment: 51 pages, 36 figures, submitted to A&

    Cosmic-ray Heavy Nuclei at Geomagnetic Latitude 42°N

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    The flux of primary cosmic ray heavy nuclei has been measured with a sandwich of C.2 and G.5 emulsions near the coast of Georgia, magnetic latitude 42°N. The emulsions were exposed at about 122 000 ft for 7.5 hours and the calculated fluxes at the top of the atmosphere in particles/ m2-sec-sr were found to be: Li, Be, B (L nuclei) 1.15.±0.3 C,N,O,F (M nuclei) 3.97±0.4 z≥10 (H nuclei) 1.29±0.3 This flight took place on May 25, 1960, near sun spot maximum. Evidence of solar modulation of the primary cosmic ray flux is shown

    “Helping fill that gap:” a qualitative study of aging in place after disaster through the lens of home-based care providers

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    Abstract Background During a disaster, home-based care fills the critical need for continuation of health care. Home-based care is intended to function using existing care delivery models, continuing to provide care for patients wherever they are located, including in shelters and hotels. Home-based care providers are often the closest in contact with their patients —seeing them in place, even throughout a disaster— through which they develop a unique insight into aging in place during a disaster. The purpose of this study was to identify individual and community-level support needs of older adults after a disaster through the lens of home-based care providers. Methods Using qualitative inquiry, five focus groups were conducted with home-based care providers (n = 25) who provided in-home care during Hurricane Irma and Hurricane Harvey. Participants were identified by contacting home health agencies listed in an open-source database of agencies participating in Centers for Medicare and Medicaid Services programs. Data were coded using an abductive analytic approach, and larger themes were generated in light of existing theory. Results The results were distilled into eight themes that related to the importance of community and family, informal and formal supports throughout the disaster management cycle, maintaining autonomy during a disaster, and institutional and systemic barriers to obtaining assistance. Conclusions In this study, home-based care providers described the challenges aging adults face in the response and recovery period after a large-scale disaster including maintaining continuity of care, encouraging individual preparedness, and accessing complex governmental support. Listening to home-based care providers offers new and important insights for developing interventions to address social and health needs for older adults aging in place after a large-scale disaster.http://deepblue.lib.umich.edu/bitstream/2027.42/173551/1/12877_2021_Article_2159.pd

    A Hubble Space Telescope

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