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31.
Sutton T Baumann U Hayes J Collins NC Shi BJ Schnurbusch T Hay A Mayo G Pallotta M Tester M Langridge P 《Science (New York, N.Y.)》2007,318(5855):1446-1449
32.
Measurements of electrical conductivity at high pressure and temperature were taken on the lower mantle phase magnesiowustite with varying Fe3+ content. Although previous measurements at atmospheric pressure suggest Fe2+-Fe3+ hopping (small polaron) as the dominant conductivity mechanism, the present experiments show a change in charge transport mechanism with temperature. The lower temperature measurements are consistent with small polaron conduction, but at higher temperatures, which are more applicable to the lower mantle, a large polaron mechanism is suggested. Because these mechanisms have different temperature and compositional dependencies, this transition has important implications for extrapolation to mantle conditions. 相似文献
33.
Extension of day length by artificial light in selected field plots in the fall prevented 76 percent of European corn borer [Ostrinia nubilalis (Hübner)] larvae and 70 percent of codling moth [Laspeyresia pomonella (L.)] larvae from entering diapause. Nondiapausing insects cannot survive rigorous winter conditions. 相似文献
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Use of U.S. croplands for biofuels increases greenhouse gases through emissions from land-use change 总被引:3,自引:0,他引:3
Searchinger T Heimlich R Houghton RA Dong F Elobeid A Fabiosa J Tokgoz S Hayes D Yu TH 《Science (New York, N.Y.)》2008,319(5867):1238-1240
Most prior studies have found that substituting biofuels for gasoline will reduce greenhouse gases because biofuels sequester carbon through the growth of the feedstock. These analyses have failed to count the carbon emissions that occur as farmers worldwide respond to higher prices and convert forest and grassland to new cropland to replace the grain (or cropland) diverted to biofuels. By using a worldwide agricultural model to estimate emissions from land-use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products. 相似文献
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Hayes E 《Science (New York, N.Y.)》1922,55(1430):567-568
40.
Isolation of St. Louis encephalitis virus from overwintering Culex pipiens mosquitoes 总被引:3,自引:0,他引:3
C L Bailey B F Eldridge D E Hayes D M Watts R F Tammariello J M Dalrymple 《Science (New York, N.Y.)》1978,199(4335):1346-1349
Two strains of St. Louis encephalitis virus were isolated from overwintering mosquitoes collected in Maryland and Pennsylvania during January and February 1977. There isolations from Culex pipiens constitute evidence that a mosquito-borne flavivirus can persist in a vector mosquito in temperate climates during the winter season. 相似文献