309 research outputs found

    Picketing

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    Neutron-capture gamma-ray analysis of coal for sulfur, iron, silicon and moisture

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    Samples of coal weighing approximately 200 grams placed in a collimated beam of neutrons from the thermal column of the Ames Laboratory Research Reactor produced capture gamma-rays which could be used for the simultaneous determination of sulfur and iron. Spectra from NaI(Tl) and Ge(Li) detectors were used and interferences were located by examining spectra of the major elemental components of coal. In determining sulfur, iron is a potential source of interference when gamma-ray spectra are collected with a NaI(Tl) detector. Corrections for iron interference were made by use of a higher energy iron peak. The possibility of determining silicon in coal was investigated but this element determination was unsuccessful since capture gamma-ray spectrometry lacked the necessary sensitivity for silicon. A linear relation was found between the area of the hydrogen capture peak at 2.23 MeV and the amount of water added to coal

    Observations on the biology of Schistocerca venusta

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    Statement Qf the problem. The green valley grasshopper, Schistoceroa venusta Scudder, is one of the most common grasshoppers to be found in the San Joaquin Valley and environs. Despite the fact that the insect is commonplace, very little work has been done on its biology. It was the purpose of this study, therefore, to learn by field and laboratory observations of the life cycle and habits of Schistoceroa venusta

    Discovery of a 3.6-hr Eclipsing Luminous X-Ray Binary in the Galaxy NGC 4214

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    We report the discovery of an eclipsing X-ray binary with a 3.62-hr period within 24" of the center of the dwarf starburst galaxy NGC 4214. The orbital period places interesting constraints on the nature of the binary, and allows for a few very different interpretations. The most likely possibility is that the source lies within NGC 4214 and has an X-ray luminosity of up to 7 e38 ergs/s. In this case the binary may well be comprised of a naked He-burning donor star with a neutron-star accretor, though a stellar-mass black-hole accretor cannot be completely excluded. There is no obvious evidence for a strong stellar wind in the X-ray orbital light curve that would be expected from a massive He star; thus, the mass of the He star should be <3-4 solar masses. If correct, this would represent a new class of very luminous X-ray binary -- perhaps related to Cyg X-3. Other less likely possibilities include a conventional low-mass X-ray binary that somehow manages to produce such a high X-ray luminosity and is apparently persistent over an interval of years; or a foreground AM Her binary of much lower luminosity that fortuitously lies in the direction of NGC 4214. Any model for this system must accommodate the lack of an optical counterpart down to a limiting magnitude of 22.6 in the visible.Comment: 7 pages, ApJ accepted versio

    Book Reviews

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    Ada style guide (version 1.1)

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    Ada is a programming language of considerable expressive power. The Ada Language Reference Manual provides a thorough definition of the language. However, it does not offer sufficient guidance on the appropriate use of Ada's powerful features. For this reason, the Goddard Space Flight Center Ada User's Group has produced this style guide which addresses such program style issues. The guide covers three areas of Ada program style: the structural decomposition of a program; the coding and the use of specific Ada features; and the textural formatting of a program

    Is It the Company's or Mine? Perceived Organizational Justice Practices and the Ownership of Job Knowledge

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    This study examined the factors that determine a workers willingness to share private knowledge gained on the job. The recent vogue in knowledge management studies typically assumes that workers naturally are willing to share what they have learned, but economic theory suggests that there should be powerful disincentives to share. We explored justice practices, individual personality, the psychological contract, organizational commitment and their relationships to worker ownership. Results indicated that procedural and distributive justice had opposite effects on knowledge ownership, while psychological contract breach and continuance commitment had positive, direct effects on knowledge ownership
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