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531.
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Wurr D. C. E.; Fellows J. R.; Phelps K.; Reader R. J. 《Journal of experimental botany》1995,46(10):1487-1496
Using data from an experiment in controlled environment cabinets,with temperatures between 7 C and 23 C, a model of vernalizationwas developed which predicts the change in apex diameter ofcalabrese with temperature. The model does not include a juvenilephase and the rate of diameter growth is maximal at 15.8 C.When tested on field-grown crops of two cultivars, the modeldescribed apex expansion well. Key words: Model, cardinal temperatures, juvenility, vernalization, initiation 相似文献
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S M Pfiffner A V Palumbo T J Phelps T C Hazen 《Journal of industrial microbiology & biotechnology》1997,18(2-3):204-212
In in situ bioremediation demonstration at the Savannah River Site in Aiken, South Carolina, trichloroethylene-degrading microorganisms
were stimulated by delivering nutrients to the TCE-contaminated subsurface via horizontal injection wells. Microbial and
chemical monitoring of groundwater from 12 vertical wells was used to examine the effects of methane and nutrient (nitrogen
and phosphorus) dosing on the methanotrophic populations and on the potential of the subsurface microbial communities to
degrade TCE. Densities of methanotrophs increased 3–5 orders of magnitude during the methane- and nutrient-injection phases;
this increase coincided with the higher methane levels observed in the monitoring wells. TCE degradation capacity, although
not directly tied to methane concentration, responded to the methane injection, and responded more dramatically to the multiple-nutrient
injection. These results support the crucial role of methane, nitrogen, and phosphorus as amended nutrients in TCE bioremediation.
The enhancing effects of nutrient dosing on microbial abundance and degradative potentials, coupled with increased chloride
concentrations, provided multiple lines of evidence substantiating the effectiveness of this integrated in situ bioremediation process.
Received 13 November 1995/ Accepted in revised form 12 September 1996 相似文献
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Abstract In situ concentrations of hydrogen and other metabolites involved in H2 -consuming and H2 -producing reactions were measured in anoxic methanogenic lake sediments, sewage sludge and fetid liquid of cottonwood. The data were used to calculate the Gibbs free energies of the metabolic reactions under the conditions prevailing in situ. The thermodynamics of most of the reactions studied were exergonic with Gibbs free energies being more negative for H2 -dependent sulfate reduction methanogenesis acetogenesis and for H2 -producing lactate fermentation ethanol fermentation. Butyrate and propionate fermentation, on the other hand, were endergonic under in situ conditions. This observation is interpreted by suggesting that butyrate and propionate is degraded within microbial clusters which shield the fermentating bacteria from the outside H2 (and acetate) pool. 相似文献
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Oecologia - Environmental and biological context play significant roles in modulating physiological stress responses of individuals in wildlife populations yet are often overlooked when evaluating... 相似文献
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