53 research outputs found
Retention, Detention and Overland Flow for Pollutant Removal from Highway Stormwater Runoff, Volume II: Design Guidelines
DTFH61-85-C-00117This volume is the second in a two-volume report which developed design guidelines and specifications for measures to reduce or eliminate the impacts of highway runoff on surface waters. This report provides design guidelines and specifications for three types of management measures for the removal of pollutants from highway stormwater runoff. The three general types of management measures, determined through previous FHWA studies to be effective in treating highway runoff, are: retention systems (basins, trenches, and wells), detention basins (wet detention basins, dry extended detention basins, and wetlands), and overland flow (grassed channels and filter strips). These guidelines have been developed based on the experience of the project team, review of available literature, and bench-scale and field testing
Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy
We review HB stars in a broad astrophysical context, including both variable
and non-variable stars. A reassessment of the Oosterhoff dichotomy is
presented, which provides unprecedented detail regarding its origin and
systematics. We show that the Oosterhoff dichotomy and the distribution of
globular clusters (GCs) in the HB morphology-metallicity plane both exclude,
with high statistical significance, the possibility that the Galactic halo may
have formed from the accretion of dwarf galaxies resembling present-day Milky
Way satellites such as Fornax, Sagittarius, and the LMC. A rediscussion of the
second-parameter problem is presented. A technique is proposed to estimate the
HB types of extragalactic GCs on the basis of integrated far-UV photometry. The
relationship between the absolute V magnitude of the HB at the RR Lyrae level
and metallicity, as obtained on the basis of trigonometric parallax
measurements for the star RR Lyrae, is also revisited, giving a distance
modulus to the LMC of (m-M)_0 = 18.44+/-0.11. RR Lyrae period change rates are
studied. Finally, the conductive opacities used in evolutionary calculations of
low-mass stars are investigated. [ABRIDGED]Comment: 56 pages, 22 figures. Invited review, to appear in Astrophysics and
Space Scienc
Resonant and off-resonant transients in electromagnetically induced transparency: Turn-on and turn-off dynamics
Published versio
Retention, Detention, and Overland Flow for Pollutant Removal from Highway Stormwater Runoff, Volume I: Research Report
DTFH61-85-C-00117This volume is the first in a two-volume report which developed design guidelines and specifications for measures to reduce or eliminate the impacts of highway runoff on surface waters. This volume documents the research performed under this project. It presents the findings of literature reviews, laboratory bench-scale testing, and actual field monitoring of pollution control measures (grassed channels and wet detention basins)
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