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D. C. Coleman R. V. Anderson C. V. Cole E. T. Elliott L. Woods M. K. Campion 《Microbial ecology》1977,4(4):373-380
Flows of biomass and respiratory carbon were studied in a series of propylene-oxide sterilized soil microcosms. One-half of the microcosms received three pulsed additions of 200 ppm glucose-carbon to mimic rhizosphere carbon inputs. Biotic variables were: bacteria (Pseudomonas) alone, or amoebae (Acanthamoeba) and nematodes (Mesodiplogaster) singly, or both combined in the presence of bacteria.Over the 24-day experiment, respiration was significantly higher in the microcosms containing the bacterial grazers. Biomass accumulation by amoebae was significantly higher than that by nematodes. The nematodes respired up to 30-fold more CO2 per unit biomass than did amoebae. Similar amounts of carbon flowed into both respiratory and biomass carbon in microcosms with fauna, compared with the bacteria-alone microcosms. However, partitioning of available carbon by the microfauna varied considerably, with little biomass production and relatively more CO2-C produced in the nematode-containing microcosms. The amoebae, in contrast, allocated more carbon to tissue production (about 40% assimilation efficiency) and correspondingly less to CO2. 相似文献
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K Maskos 《Acta biochimica Polonica》1985,32(3):235-250
The copper (II)-inosine system in water-DMSO solutions was investigated as a function of pH and the molar ratio between the ligand and copper(II) ion by the EPR, NMR, CD and visible absorption spectrometric methods. It was concluded that a simple M.[-N]L copper(II)-inosine 1:1 complex is formed over the pH range 1.4-5.0, while M.[-N]L2 complexes are present in the solutions of pH 5.0-6.2. From pH 6.2 to 7.8 a diamagnetic, hydroxybridged complex M2.(OH)2.[-N]L4 dominates. At pH values of 7.8-9.2 an insoluble, oxybridged species (M.O.[-N]L)n is formed in addition to the soluble paramagnetic M.[-N-1)L4 complex. Above pH 9.1 the nitrogenbridged polymeric complex (M.[-N-1].M[-N-7] )n is formed which is stable up to pH 12.5, and above pH 12.5 the only species found is the M.[-OH]L2 chelate complex in which inosine is coordinated to copper through the two ionized hydroxyl groups. 相似文献
997.
In view of the importance of impedance plethysmography requirements are formulated for a modern impedance measuring device basing on a long experience with this method of measurement. The principle mode of action of the measuring equipment and the pneumatics with the timing element are described. A number of recordings is shown to illustrate the universality of the measuring equipment. 相似文献
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