7,338 research outputs found

    Flame retardant spandex type polyurethanes

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    Flame retardant elastomeric compositions were developed, comprised of: (1) spandex type polyurethane having incorporated into the polymer chain, halogen containing polyols; (2) conventional spandex type polyurethanes in physical admixture flame retardant additives; and (3) fluoroelastomeric resins in physical admixture with flame retardant additives. Methods of preparing fibers of the flame retardant elastomeric materials are presented and articles of manufacture comprised of the elastomeric materials are mentioned

    Flame resistant elastic elastomeric fiber

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    Compositions exhibit elastomeric properties and possess various degrees of flame resistance. First material polyurethane, incorporates halogen containing polyol and is flame resistant in air; second contains spandex elastomer with flame retardant additives; and third material is prepared from fluorelastomer composition of copolymer of vinylidene fluoride and hexafluoropropylene

    Flame resistant elastomeric polymer development

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    Elastomeric products were developed for use in the space shuttle program, and investigations were conducted to improve the properties of elastomers developed in previous programs, and to evaluate the possibility of using lower-cost general purpose polymers. Products were fabricated and processed on conventional processing equipment; these products include: foams based on fluorinated rubber flame-retarded compounds with a density of 20-30 pounds/cubic foot for use as padding and in helmets; foams based on urethane for use in instrument packaging in the space shuttle; flexible and semi-rigid films of fluorinated rubber and neoprene compounds that would not burn in a 70% nitrogen, 30% oxygen atmosphere, and in a 30% nitrogen, 70% oxygen atmosphere, respectively for use in packaging or in laminates; coated fabrics which used both nylon and Kelvar fabric substrates, coated with either fluorinated or neoprene polymer compositions to meet specific levels of flame retardancy; and other flame-resistant materials

    Non-flammable elastomeric fiber from a fluorinated elastomer and containing an halogenated flame retardant

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    Flame retardant elastomeric compositions are described comprised of either spandex type polyurethane having incorporated into the polymer chain halogen containing polyols, conventional spandex type polyurethanes in physical admixture with flame retardant additives, or fluoroelastomeric resins in physical admixture with flame retardant additives. Methods are described for preparing fibers of the flame retardant elastomeric materials and articles of manufacture comprised of the flame retardant clastomeric materials and non elastic materials such as polybenzimidazoles, fiberglass, nylons, etc

    The Upper Oxfordian and Lower Kimmeridgian ammonite genera Idoceras Burckhardt, 1906, and Subnebrodites Spath, 1925

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    The type species of the genera Idoceras Burckhardt and Subnebrodites Spath are clarified in order to preserve the current universal usage of the Planula Zone in the Upper Oxfordian and the Balderus Zone in the Lower Kimmeridgian of the Submediterranean Province. To protect both zones, the identification of Ammonites planula Hehl in Zieten, 1830 in 1830–1833, is investigated and found to be a nomen nudum

    Stevensites, Zittelites, and Gyrophylloceras, new generic names proposed for Stevensia Énay, 2009, Zittelia Tavera Benitez, 1985, and Gyrophyllites Wiedmann, 1963 (Mollusca: Ammonoidea)

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    Stevensites, Zittelites, and Gyrophylloceras are proposed as replacement names for the preoccupied ammonite genera Stevensia Énay, 2009, Zittelia Tavera Benitez, 1985, and Gyrophyllites Wiedmann, 1963, respectively

    Amplitude variability in satellite photometry of the non-radially pulsating O9.5V star zeta Oph

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    We report a time-series analysis of satellite photometry of the non-radially pulsating Oe star zeta Oph, principally using data from SMEI obtained 2003--2008, but augmented with MOST and WIRE results. Amplitudes of the strongest photometric signals, at 5.18, 2.96, and 2.67/d, each vary independently over the 6-year monitoring period (from ca. 30 to <2 mmag at 5.18/d), on timescales of hundreds of days. Signals at 7.19/d and 5.18/d have persisted (or recurred) for around two decades. Supplementary spectroscopic observations show an H-alpha emission episode in 2006; this coincided with small increases in amplitudes of the three strongest photometric signals.Comment: MNRAS, in pres

    The Influence of Stellar Wind Variability on Measurements of Interstellar O VI Along Sightlines to Early-Type Stars

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    A primary goal of the FUSE mission is to understand the origin of the O VI ion in the interstellar medium of the Galaxy and the Magellanic Clouds. Along sightlines to OB-type stars, these interstellar components are usually blended with O VI stellar wind profiles, which frequently vary in shape. In order to assess the effects of this time-dependent blending on measurements of the interstellar O VI lines, we have undertaken a mini-survey of repeated observations toward OB-type stars in the Galaxy and the Large Magellanic Cloud. These sparse time series, which consist of 2-3 observations separated by intervals ranging from a few days to several months, show that wind variability occurs commonly in O VI (about 60% of a sample of 50 stars), as indeed it does in other resonance lines. However, in the interstellar O VI λ\lambda1032 region, the O VI λ\lambda1038 wind varies only in ∼\sim30% of the cases. By examining cases exhibiting large amplitude variations, we conclude that stellar-wind variability {\em generally} introduces negligible uncertainty for single interstellar O VI components along Galactic lines of sight, but can result in substantial errors in measurements of broader components or blends of components like those typically observed toward stars in the Large Magellanic Cloud. Due to possible contamination by discrete absorption components in the stellar O VI line, stars with terminal velocities greater than or equal to the doublet separation (1654 km/s) should be treated with care.Comment: Accepted for publication in the Astrophysical Journal Lette

    Cocaine, treatment and public health: A case study in Merseyside and Cheshire

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    Originating from the coca plant in South America, the prevalence of cocaine use has increased in recent times and it has become a global commodity. It is the second most trafficked illicit drug in the world, after cannabis, with world seizures in 2006 amounting to 706 tonnes (EMCDDA, 2008). General population surveys show an increase in cocaine use in many European countries, especially among young people, though this may now be slowing in countries with the highest rates of use. Indicators of cocaine availability in Europe, including seizures of the drug and amounts seized have also increased dramatically in recent years, with the demand for treatment for cocaine use increasing substantially in recent years in some European countries. There is evidence to suggest that the proportions of adults (15-64 year olds) in the UK using the drug are within the top 5% in Europe (EMCDDA, 2007) and the 2008/9 British Crime Survey found that 3.0% of adults had used cocaine in the past year compared to 2.3% in 2007/8 (Hoare, 2009)
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