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31.
S. R. Aston I. Thornton J. S. Webb J. B. Purves B. L. Milford 《Water, air, and soil pollution》1974,3(3):321-325
The trace element composition of stream sediments from catchments contaminated by past and present mining activities has been used to indicate the trace element status of associated waters. The paper discusses the possibility of using geochemical reconnaissance maps based on the analysis of stream sediments as an ancillary aid to water quality evaluation. 相似文献
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Lee N Benichi H Takeno Y Takeda S Webb J Huntington E Furusawa A 《Science (New York, N.Y.)》2011,332(6027):330-333
We report on the experimental quantum teleportation of strongly nonclassical wave packets of light. To perform this full quantum operation while preserving and retrieving the fragile nonclassicality of the input state, we have developed a broadband, zero-dispersion teleportation apparatus that works in conjunction with time-resolved state preparation equipment. Our approach brings within experimental reach a whole new set of hybrid protocols involving discrete- and continuous-variable techniques in quantum information processing for optical sciences. 相似文献
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Adherent bacterial colonization in the pathogenesis of osteomyelitis 总被引:12,自引:0,他引:12
Direct scanning electron microscopy of material obtained during surgical debridement of osteomyelitic bone showed that the infecting bacteria grew in coherent microcolonies in an adherent biofilm so extensive it often obscured the infected bone surfaces. Transmission electron microscopy showed this biofilm to have a fibrous matrix, to contain some host cells, and to contain many bacteria around which matrix fibers were often concentrated. Many bacterial morphotypes were present in these biofilms, and each bacterium was surrounded by exopolysaccharide polymers, which are known to mediate formation of microcolonies and adhesion of bacteria to surfaces in natural ecosystems and in infections related biomaterials. The adherent mode of growth may reduce the susceptibility of these organisms to host clearance mechanisms and antibiotic therapy and thus may be a fundamental factor in acute and chronic osteomyelitis. 相似文献
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The various isotope effects on the superconducting transition temperature of Mo(2)B and W(2)B have been measured. Together with resistivity data they indicate that the d-shell forms a highly stable electron configuration for molybdenum and tungsten. This leads to an understanding of high superconducting transition temperatures. 相似文献
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Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage 总被引:3,自引:0,他引:3
Dodd AN Salathia N Hall A Kévei E Tóth R Nagy F Hibberd JM Millar AJ Webb AA 《Science (New York, N.Y.)》2005,309(5734):630-633
Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long- and short-circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control. 相似文献
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