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241.
Duncan C. Blanchard 《Estuaries and Coasts》1989,12(3):127-137
This paper is a review of work done on the production of an aerosol by the sea, and on the mechanisms by which bacteria might be enriched on the aerosol. Air bubbles produced in the sea, primarily by breaking waves, burst at the surface to eject both film and jet drops into the atmosphere. These drops are mixed upward by turbulence to produce the well-known marine sea-salt aerosol. In rising through the water, the bubbles may scavenge bacteria which, when the bubble burst, are skimmed off the bubble and ejected upward with the jet drops. Depending on drop size, the distance the bubble moves through the water, and other factors, the concentration of bacteria in jet drops can be several hundred times that in the bulk water film drops can also be enriched with bacteria. The enrichment of jet and film drops with bacteria, viruses, or toxins may at times produce a health hazard for those living along the shore. 相似文献
242.
Kerry L. Sublette J. Bryan Tapp J. Berton Fisher Eleanor Jennings Kathleen Duncan Greg Thoma Josh Brokaw Tim Todd 《Applied Geochemistry》2007
For almost a decade the Tallgrass Prairie Preserve in Oklahoma has been used as a field laboratory for the investigation of aspects of the remediation and restoration of oil and brine spills. Objectives of this work have included: (1) simplification of the remediation process and lowering the cost of remediation; (2) the development of methods to accelerate or jump-start the restoration process; and (3) determining appropriate metrics for assessing the status of soil ecosystem recovery. This research has resulted in a number of lessons learned that will be presented here which can be exported to other exploration and production sites, especially sites located in sensitive ecosystems. Key observations have included the role of a fertilizer amendment in linking the remediation and restoration process at an oil-impacted site, the use of nematodes as ecological indicators in the restoration of oil- and brine-impacted sites, and the development of a two-stage process for remediation of brine impacted sites that does not include significant use of gypsum. 相似文献
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Göğüş E Woods PM Kouveliotou C van Paradijs J Briggs MS Duncan RC Thompson C 《The Astrophysical journal》2000,532(2):L121-L124
We present statistics of SGR 1806-20 bursts, combining 290 events detected with the Rossi X-Ray Timing Explorer/Proportional Counter Array, 111 events detected with the Burst and Transient Source Experiment, and 134 events detected with the International Cometary Explorer. We find that the fluence distribution of bursts observed with each instrument are well described by power laws with indices 1.43, 1.76, and 1.67, respectively. The distribution of time intervals between successive bursts from SGR 1806-20 is described by a lognormal function with a peak at 103 s. There is no correlation between the burst intensity and either the waiting times until the next burst or the time elapsed since the previous burst. In all these statistical properties, SGR 1806-20 bursts resemble a self-organized critical system, similar to earthquakes and solar flares. Our results thus support the hypothesis that the energy source for soft gamma repeater bursts is crustquakes due to the evolving, strong magnetic field of the neutron star, rather than any accretion or nuclear power. 相似文献
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Finding the repeat times of the GPS constellation 总被引:5,自引:6,他引:5
Single-epoch estimates of position using GPS are improved by removing multipath signals, which repeat when the GPS constellation does. We present two programs for finding this repeat time, one using the orbital period and the other the topocentric positions of the satellites. Both methods show that the repeat time is variable across the constellation, at the few-second level for most satellites, but with a few showing much different values. The repeat time for topocentric positions, which we term the aspect repeat time, averages 247 s less than a day, with fluctuations through the day that may be as much as 2.5 s at high latitudes. 相似文献
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This paper examines changes in gender relations in a small coastal community as a result of the 2010 Chile earthquake and tsunami. Vulnerability and resilience are used as a conceptual framework to analyse these changes. Based on empirical evidence from a seven-year longitudinal study and quasi-ethnographic work, we explore changes in power relations at the different stages of the disaster and longer-term recovery as well as the conditions that fostered these changes. Our findings show distinct patterns of change. First, disasters can trigger long-lasting changes that challenge historical patriarchal relations. Second, while vulnerability increases following a disaster, resilience can potentially counteract women’s vulnerability. We propose that resilience can be a pathway to produce long-term changes in gender relations and empower women in the context of disasters. 相似文献
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