Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil ...Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil available K. The soil K tested by CEM was significantly correlated with that by the other (conventional) methods (r2=0.43**~0.95***). The soil K tested by CEM saturated with NH4HCO3 (15 min extraction) was most closely correlated with that by the other methods (2 =0. 60***~0.95***). Potassium availability, as predicted by soil test, was comparable to actual K uptake by canola and wheat grown on the soils in growth chamber. Regression analyses showed that plant K uptake was more closely correlated with K extracted by CEM (r2=0.56***~0.81***) than that by the conventional methods (r2=0.46***~;0.81***), most closely correlsted with that by NH4HCO3-saturated CEM for 15 min (r2=0.81***), and worst correlated with that by HNO3 (r2=0.45**~0.72***).展开更多
This paper summarizes the results of separation and purification of 234Th from aged uranium salt with two processes (see flowsheet A or B). The flowsheet A: TBP extraction, anion exchange and TTA extraction; the flows...This paper summarizes the results of separation and purification of 234Th from aged uranium salt with two processes (see flowsheet A or B). The flowsheet A: TBP extraction, anion exchange and TTA extraction; the flowsheet B: Canon and anionexchange, TTA extraction. The total recovery efficiency of 234Th is about 90 %. The γ-spectrum of the end-product contains only two typic peaks of 234Th (63 and 92 keV). Pure 234Th is prepared.展开更多
文摘Four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil available K. The soil K tested by CEM was significantly correlated with that by the other (conventional) methods (r2=0.43**~0.95***). The soil K tested by CEM saturated with NH4HCO3 (15 min extraction) was most closely correlated with that by the other methods (2 =0. 60***~0.95***). Potassium availability, as predicted by soil test, was comparable to actual K uptake by canola and wheat grown on the soils in growth chamber. Regression analyses showed that plant K uptake was more closely correlated with K extracted by CEM (r2=0.56***~0.81***) than that by the conventional methods (r2=0.46***~;0.81***), most closely correlsted with that by NH4HCO3-saturated CEM for 15 min (r2=0.81***), and worst correlated with that by HNO3 (r2=0.45**~0.72***).
文摘This paper summarizes the results of separation and purification of 234Th from aged uranium salt with two processes (see flowsheet A or B). The flowsheet A: TBP extraction, anion exchange and TTA extraction; the flowsheet B: Canon and anionexchange, TTA extraction. The total recovery efficiency of 234Th is about 90 %. The γ-spectrum of the end-product contains only two typic peaks of 234Th (63 and 92 keV). Pure 234Th is prepared.