1,623 research outputs found

    Canister for Producing TMA Trails in the Upper Atmosphere

    Get PDF
    Payload canister for producing trimethyl aluminum trails in upper atmosphere using Nike-Cajun or Nike-Apache rocke

    Optical properties of silicon carbide for astrophysical applications I. New laboratory infrared reflectance spectra and optical constants

    Full text link
    Silicon Carbide (SiC) optical constants are fundamental inputs for radiative transfer models of astrophysical dust environments. However, previously published values contain errors and do not adequately represent the bulk physical properties of the cubic (beta) SiC polytype usually found around carbon stars. We provide new, uncompromised optical constants for beta- and alpha-SiC derived from single-crystal reflectance spectra and investigate quantitatively whether there is any difference between alpha- and beta-SiC that can be seen in infrared spectra and optical functions. Previous optical constants for SiC do not reflect the true bulk properties, and they are only valid for a narrow grain size range. The new optical constants presented here will allow narrow constraints to be placed on the grain size and shape distribution that dominate in astrophysical environments. In addition, our calculated absorption coefficients are much higher than laboratory measurements, which has an impact on the use of previous data to constrain abundances of these dust grains.Comment: 12 pages; 10 figures; laboratory optical constants available from CDS. Accepted by Astronomy & Astrophysic

    Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 3: Energy Conversion subsystems and components. Part 2: Primary heat input systems and heat exchangers

    Get PDF
    Primary heat input systems and heat exchangers were evaluated for advanced energy conversion systems. Results are presented and discussed

    Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 3: Energy conversion subsystems and components. Part 3: Gasification, process fuels, and balance of plant

    Get PDF
    Results are presented of an investigation of gasification and clean fuels from coal. Factors discussed include: coal and coal transportation costs; clean liquid and gas fuel process efficiencies and costs; and cost, performance, and environmental intrusion elements of the integrated low-Btu coal gasification system. Cost estimates for the balance-of-plant requirements associated with advanced energy conversion systems utilizing coal or coal-derived fuels are included

    Synthesis of bulk, dense, nanocrystalline yttrium aluminum garnet from amorphous powders

    Get PDF
    Amorphous powders of Al2O3x2014;37.5 mol% Y2O3 (yttrium aluminum garnet (YAG)) were prepared by coprecipitation, decomposed at 800xB0;C, and hot-pressed uniaxally at low temperature (600xB0;C) and a moderate pressure (750 MPa). Optimum conditions yielded microstructures with only 2% porosity and partial crystallization of YAG. Further processing using high quasi-hydrostatic pressure (1 GPa) at 1000xB0;C enabled the production of fully crystallized YAG with gt;96% relative density and a nanocrystalline grain size of x223C;70 nm. 13

    L-Lysine Imprinted Nanoparticles for Antibody Biorecognition

    Get PDF
    The aim of this study was to prepare L-lysine-imprinted poly(HEMA-MAAsp) nanoparticles which can be used for the adsorption of IgG from aqueous solutions. L-lysine was complexed with MAAsp and Llysine- imprinted poly(HEMA-MAAsp) nanoparticles were synthesized by miniemulsion polymerization. Also, non-imprinted nanoparticles were synthesized without L-lysine for control purpose. L-lysine-imprinted poly(HEMA-MAAsp) nanoparticles were characterized by means of elemental analysis, Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3500
    corecore