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Research has documented how grass-roots activists deploy the environmental justice frame to convey their grievances and demand their right to health and safety. While scholars have highlighted the widespread success of this frame, little attention has been paid to instances where the environmental justice frame fails to resonate. Drawing from social movements and environmental justice literatures, we examine how local discursive and cultural contexts can pose barriers to environmental justice claims. Our case is based on legacy pollution from a decommissioned creosote facility in Southern Mississippi. When black residents discovered the pollution in their neighborhood, they made repeated appeals to authorities for remediation and compensation. After being denied inclusion in a lawsuit filed by white residents, they formed an environmental justice organization to mobilize support for their campaign. Findings reveal the importance of both historical contextualization and the social situation of frame deployers in analyses of the environmental justice frame. 相似文献
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The magnitude m bLg 5.0 Mont-Laurier earthquake of 1990 October 19, in Quebec, Canada, was one of the largest to have occurred in eastern North America during the past decade. High-frequency ground motions recorded on regional network instruments exceeded values anticipated for an event of its size by a factor of 3. A commonly favoured explanation for the discrepancy is that the source was a rare 'high-stress' event. In this paper, detailed fault-slip models are derived to fit waveform and spectral characteristics of the regional data. The results establish that the effective rupture stress was normal (about 100 bars), that the fault rupture developed asymmetrically, and that the average slip time for points inside the rupture area (approx. 0.1 s) was significantly less than that associated with the standard Brune (1970) source spectral model. The rupture area developed in at least four distinct episodes, each extending the previously ruptured area. Taken together with similar results for the m bLg 6.5 Saguenay earthquake of 1988 November, the results indicate that a widely used assumption in hazard analyses, that earthquake spectra are adequately represented by the standard Brune spectral model, is unreliable for the interpretation and prediction of strong ground motion. 相似文献
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R. H. Adams R. A. Cerecedo-López L. A. Alejandro-Álvarez V. I. Domínguez-Rodríguez J. L. Nieber 《International Journal of Environmental Science and Technology》2016,13(9):2249-2260
A pipeline right-of-way contaminated with light crude in 1979 and subsequently burned shows severe hydrophobicity, poor infiltration rates, and loss of vegetative cover. To evaluate alkaline desorption as a treatment method, surface soil samples were collected and analyzed pre- and post-treatment. Samples had total petroleum hydrocarbon concentrations of 2800–63,100 mg/kg, severe water repellency, critical moisture 2–5 times above the in situ moisture content, but no acute toxicity. Thus, water repellency, rather than toxicity, is causing the loss of vegetation. Samples were treated with 0.1 N NaOH in two doses (1:3; soil/solution), with complete drainage between doses. Finally, each soil sample was washed with an equal volume or water and allowed to drain completely. For more hydrophobic samples, repeated treatments, without rinsing between each treatment, were made. Post-treatment, the samples were re-analyzed for water repellency and critical moisture content. In samples with initial water repellency values in the range of 5.0–6.7 M, the repellency was reduced 94–100 % and below critical levels to avoid soil hydrophobicity in field conditions. The other samples with initial water repellency values in the range of 10–13 M could not be recovered with single treatment, but sequential treatments reduced the hydrocarbon content up to 87 % and reduced the hydrophobicity to levels low enough or nearly low enough to avoid severe water repellency in the field. Currently, field studies are being carried out to evaluate this treatment method at the site, as a stand-alone method and in combination with organic amendment. 相似文献
87.
Matthew D. Adams Pavlos S. Kanaroglou Paulin Coulibaly 《International journal of geographical information science》2016,30(2):390-404
Water monitoring networks are generally classified into surface water, precipitation, groundwater or water quality monitoring networks. The design of these networks typically occurs in isolation from each other. We present a regionalization approach to identify homogeneous subregions of large basins that are suitable as areas for the optimization of an integrated water monitoring network. The study area, which comprises a portion of the St. Lawrence Basin, was spatially divided using ecological units. For each ecological unit, 21 attributes were derived including both environmental and hydrological indicators. A spatially constrained regionalization technique was applied to define the final regions. A scree plot was used to determine the number of regions. The sensitivity of the technique to the correlation in the attribute data was removed by utilizing principal component analysis to reduce correlation between attribute data. During regionalization, the component values were weighted by their proportion of the total variance explained. The four regions in the final configuration had areas from 19% to 31% of the total area, 63,597 km2. For the St. Lawrence Basin, this approach is effective for defining homogeneous regions that can be used in further research on the optimization of integrated water monitoring networks. The approach is portable to other regions and can incorporate any set of attribute data that is valuable to the regionalization objective. 相似文献
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A. D. Edens R. G. Adams P. K. Rambo I. C. Smith J. L. Porter T. Ditmire 《Astrophysics and Space Science》2007,307(1-3):127-130
We have performed a series of experiments examining the properties of high Mach number blast waves. Experiments were conducted
on the Z-Beamlet laser at Sandia National Laboratories. We created blast waves in the laboratory by using ∼1000 J laser pulses
to illuminate millimeter scale solid targets immersed in gas. Our experiments studied the validity of theories forwarded by
Ryu and Vishniac (1987, 1991) and Vishniac (1983) to explain the dynamics of perturbations on astrophysical blast waves. These
experiments consisted of a systematic scan of the decay rates of perturbations of known primary mode number induced on the
surface of blast waves by means of a regularly spaced wire array. The amplitude of the induced perturbations relative to the
radius of the blast wave was tracked and fit to a power law in time. Measurements were taken for a number of different mode
numbers in a mixed gas consisting of 7.5 Torr xenon and 2.5 Torr nitrogen and the results are compared to theoretical predictions.
It is found that two of the three mode numbers imply one polytropic index while the third case, which is the most complicated
for several reasons, implies a higher polytropic index. 相似文献