12,257 research outputs found
The Ocean Dumping Deadline: Easing the Mandate Millstone
This Article examines the development the mandate millstone, the inflexible federal rules and regulations directed at state and local governments in the environmental arena. It surveys how the mandate millstone has burdened or threatened to burden the ocean dumping of sewage sludge by New York City. The Article reviews the method by which the city has traditionally disposed of its sewage sludge in the ocean waters surrounding the city, and how the city\u27s disposal practices would have been altered radically had the city been forced to implement a plan, pursuant to United States Environmental Protection Agency (EPA) regulations, to end its ocean dumping by December 31, 1981. The Article also traces the legislative history of the imposition of this rigid deadline, as well as the problems it posed and the development of widespread opposition to its enforcement. It discusses recent events which have spared New York City from conforming to the deadline, and what these events portend for ocean dumping practices in general. Finally, it considers the implications of these events for the development of the mandate millstone and for the process through which that millstone can be eased without undermining legitimate national goals
The Inverse Compton Thermostat in Hot Plasmas Near Accreting Black Holes
The hard X-ray spectra of accreting black holes systems are generally
well-fit by thermal Comptonization models with temperatures keV. We
demonstrate why, over many orders of magnitude in heating rate and seed photon
supply, hot plasmas radiate primarily by inverse Compton scattering, and find
equilibrium temperatures within a factor of a few of 100 keV. We also determine
quantitatively the (wide) bounds on heating rate and seed photon supply for
which this statement is true.
Plasmas in thermal balance in this regime obey two simple scaling laws, one
relating the product of temperature and optical depth to the ratio of seed
photon luminosity to plasma heating rate , the other relating the
spectral index of the output power-law to . Because is almost
independent of everything but , the observed power law index may be
used to estimate . In both AGN and stellar black holes, the mean value
estimated this way is . As a corollary, must
be -- 0.2, depending on plasma geometry.Comment: 26 pages, AASLaTeX, to appear in July 10 Ap.J. Figures available in
uuencoded form at ftp://jhufos.pha.jhu.edu/pub/put/jhk/comptfigs.u
The Genus Phragmatobia in North America, with the Description of a New Species (Lepidoptera: Arctiidae)
Excerpt: This paper, based on the examination of 1,879 specimens, serves to resolve the taxonomic problems involving the three North American species of Phragmatobia. The genus Phragmatobia, the ruby tiger moths, has had a checkered history since it was described by Stephens in 1829 (type, by monotypy, Noctua j\u27uliginosa Linnaeus, 1758). Although many species have been described in or transferred to this genus, in both the Old and New Worlds, most of them have been removed to other genera. By 1902 Dyar recognized only two North American species, a status since then unchanged (McDunnough, 1938; Forbes, 1960). Despite the recent stability of the names, there has been much confusion as to which names to apply to particular specimens. This problem is resolved below, with the description of a third North American species, long confused with the two named species
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