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101.
Lewis W. Mayron John J. Winterhalter 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1085-1088
Peterson and Sabersky1 measured the concentrations of ozone, carbon monoxide, nitrogen oxide, and oxides of nitrogen under standard driving conditions in the Southern California area. They indicate that in an automobile with no inside source of carbon monoxide (CO), the interior concentrations will reflect those on the outside but in a more gradual manner. They did not record the rapid variations and high peaks in the interior that they did when samplings were taken from the outside. They reported that 25 ppm of CO was not often exceeded and the highest concentration of CO encountered was 45 ppm for a period of 3 min. 相似文献
102.
Maturity,fecundity, and reproductive cycle of the spotted ratfish, <Emphasis Type="Italic">Hydrolagus colliei</Emphasis> 总被引:1,自引:1,他引:0
Lewis A. K. Barnett Ryan L. Earley David A. Ebert Gregor M. Cailliet 《Marine Biology》2009,156(3):301-316
Size at maturity, fecundity, and reproductive periodicity were estimated for the spotted ratfish, Hydrolagus colliei (Lay and Bennett, 1839), off the coast of California, Oregon, and Washington. Maximum body size and size at median maturity
were greater for females than males. Skeletal muscle concentrations of the steroid hormones testosterone (T) and estradiol
(E2) predicted similar, but slightly smaller sizes at maturity than the morphological criterion. Stage of maturity for males
was estimated identically using internal organs or external secondary sexual characters, thus allowing non-lethal maturity
assessments. Size at median maturity was greater north of Point Conception for females, and north of Cape Mendocino for males.
Peak parturition occurred from May to October, with increased concentrations of E2 in skeletal muscle of females correlating with ovarian recrudescence during November to February. No significant seasonal
trends in female T were apparent, but mean female 11-ketotestosterone (11KT) was 300% greater in April than any other month
during the parturition season. There was a marginal evidence for increased number and size of ova with maternal size. Extrapolation
of the hypothesized 6 to 8-month egg-laying season to observed mean parturition rates of captive specimens yielded an estimated
annual fecundity of 19.5–28.9 egg cases. Differences in fecundity among higher taxonomic classifications of chondrichthyans
were detected with chimaeriform fishes more fecund than lamniform, myliobatiform, squaliform, and rhinobatiform fishes, and
less fecund than rajiform fishes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Emily A. Botts Genevieve Pence Stephen Holness Kerry Sink Andrew Skowno Amanda Driver Linda R. Harris Philip Desmet Boyd Escott Mervyn Lötter Jeanne Nel Tammy Smith Fahiema Daniels Samuel Sinclair Warrick Stewart Jeffrey Manuel 《Conservation biology》2019,33(6):1235-1246
Systematic conservation planning is intended to inform spatially explicit decision making. Doing so requires that it be integrated into complex regulatory and governance processes, and there are limited instances where this has been achieved effectively. South Africa is a global leader in the application of conservation plans, the outputs of which are widely used for spatial planning and decision making in many spheres of government. We aimed to determine how conservation planning in the country progressed from theory to implementation, and to identify practical actions that enabled this transition, by assessing temporal trends in the characteristics of conservation plans (1990–2017, n = 94). Since 2010 conservation planning has entered an operational period characterized by government leadership of plans, administrative rather than ecological planning domains, decreasing size of planning units, increasing emphasis on end-user products, and scheduled revision of plans. Key actions that enabled this progression include transitioning leadership of plans from scientists to practitioners, building capacity within implementing agencies, creating opportunities to integrate plans in legislative processes, establishing a strong community of practice, adopting implementation-focused methods, and balancing standardization with innovation. Learning from this model will allow other countries, particularly those with a similar megadiverse, developing context, to operationalize conservation planning into spatial planning and decision making. 相似文献
107.
Norma Lewis Kirankumar Topudurti Gary Welshans Robert Foster 《Journal of the Air & Waste Management Association (1995)》2013,63(4):540-547
This paper presents the Geld evaluation results of the ultraviolet radiation (UV)/oxidation technology developed by Ultrox International, Santa Ana, California. The Geld evaluation was performed at the Lorentz Barrel and Drum (LB&D) site in San Jose, California, under the Superfund Innovative Technology Evaluation program in February and March of 1989. The UV/oxidation technology uses UV radiation, ozone, and hydrogen peroxide to oxidize organic contaminants present in water. At the LB&D site, this technology was evaluated in treating ground water contaminated with volatile organic compounds (VOCs). The Ultrox system achieved VOC removals greater than 90 percent. Most VOCs were removed through chemical oxidation. However, for a few VOCs, such as 1, 1, 1-trichloroethane and 1, 1-dichloroethane, stripping also contributed toward removal. The treated ground water met the applicable discharge standards for discharge into a local waterway at 95 percent confidence level. There were no harmful air emissions to the atmosphere from the Ultrox system, which is equipped with an off-gas treatment unit. 相似文献
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Tracy R Lewis 《Journal of Environmental Economics and Management》1976,3(3):198-204
The popular notion that a monopolist will exhaust a nonrenewable natural resource at a slower than socially optimal rate is examined. Contrary to the prevailing belief, instances do exist for which the monopolist uses the resource faster than the social maximizer. This is demonstrated first by finding conditions for which the expected result—a monopoly rate which is slower than optimal-will always hold, and second, by showing that for situations where these conditions are violated the result may be reversed. 相似文献
110.
The semiconductor industry plays a leading role in supporting economic stabilization and social progress in Taiwan. In this paper, Eco-indicator 95 and Impact 2002+ are utilized to evaluate the potential environmental impacts from five production processes of the double data rate synchronous dynamic random access memory (DDR SDRAM). The comparisons between these two impact methods and their scopes are also discussed.From our results, global warming potential and non-renewable energy consumption were identified as the major environmental impacts. Applications of Eco-indicator 95 and IMPACT 2002+ also suggest that summer smog and respiratory inorganics are significant impact categories. The comparison of the scopes of these two methods identifies that low GWP potential PFCs substitution and electricity saving are effective ways to decrease environmental impacts of DRAM manufacturing. In addition, IMPACT 2002+ is a more applicable LCA method for the semiconductor industry in Taiwan due to the structure and reference area of this method and the characteristics of the semiconductor industry in Taiwan. 相似文献