2,206 research outputs found

    Health hazards of ultrafine metal and metal oxide powders

    Get PDF
    Study reveals that suggested threshold limit values are from two to fifty times lower than current recommended threshold limit values. Proposed safe limits of exposure to the ultrafine dusts are based on known toxic potential of various materials as determined in particle size ranges

    Reply to ``Comment on `Hole-burning experiments within glassy models with infinite range interactions' ''

    Full text link
    This is a reply to the comments by Richter and Chamberlin, and Diezemann and Bohmer to our paper (Phys. Rev. Lett. 85, 3448 (2000)). As further evidence for the claims in this Letter, we here reproduce the nonlinear spectral hole-burning experimental protocol in an equilibrated fully connected spin-glass model and we exhibit frequency selectivity, together with a shift in the base of the spectral hole.Comment: 1 page, two figures, to appear in Phys. Rev. Let

    Global Energetics of Thirty-Eight Large Solar Eruptive Events

    Get PDF
    We have evaluated the energetics of 38 solar eruptive events observed by a variety of spacecraft instruments between February 2002 and December 2006, as accurately as the observations allow. The measured energetic components include: (1) the radiated energy in the GOES 1 - 8 A band; (2) the total energy radiated from the soft X-ray (SXR) emitting plasma; (3) the peak energy in the SXR-emitting plasma; (4) the bolometric radiated energy over the full duration of the event; (5) the energy in flare-accelerated electrons above 20 keV and in flare-accelerated ions above 1 MeV; (6) the kinetic and potential energies of the coronal mass ejection (CME); (7) the energy in solar energetic particles (SEPs) observed in interplanetary space; and (8) the amount of free (nonpotential) magnetic energy estimated to be available in the pertinent active region. Major conclusions include: (1) the energy radiated by the SXR-emitting plasma exceeds, by about half an order of magnitude, the peak energy content of the thermal plasma that produces this radiation; (2) the energy content in flare-accelerated electrons and ions is sufficient to supply the bolometric energy radiated across all wavelengths throughout the event; (3) the energy contents of flare-accelerated electrons and ions are comparable; (4) the energy in SEPs is typically a few percent of the CME kinetic energy (measured in the rest frame of the solar wind); and (5) the available magnetic energy is sufficient to power the CME, the flare-accelerated particles, and the hot thermal plasma

    Performance of SM8 on a Test To Predict Small-Molecule Solvation Free Energies

    Get PDF
    The SM8 quantum mechanical aqueous continuum solvation model is applied to a 17-molecule test set proposed by Nicholls et al. (J. Med. Chem.2008, 51, 769) to predict free energies of solvation. With the M06-2X density functional, the 6-31G(d) basis set, and CM4M charge model, the root-mean-square error (RMSE) of SM8 is 1.08 kcal mol−1 for aqueous geometries and 1.14 kcal mol−1 for gas-phase geometries. These errors compare favorably with optimal explicit and continuum models reported by Nicholls et al., having RMSEs of 1.33 and 1.87 kcal mol−1, respectively. Other models examined by these workers had RMSEs of 1.5−2.6 kcal mol−1. We also explore the use of other density functionals and charge models with SM8 and the RMSE increases to 1.21 kcal mol−1 for mPW1/CM4 with gas-phase geometries, to 1.50 kcal mol−1 for M06-2X/CM4 with gas-phase geometries, and to 1.27−1.64 kcal mol−1 with three different models at B3LYP gas-phase geometries

    Factors affecting the artificial insemination of turkeys

    Get PDF

    A linear programming analysis of human diets based upon major staple crops: sensitivity of low cost formulations to caloric, protein and bulk constraints,

    Get PDF
    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1971.Two unnumbered leaves included in paging.Includes bibliographical references.by John G. Chamberlin.M.S
    corecore