0000000001155450
AUTHOR
R. Scelza
Azoto
1. Introduzione p. 282 2. Determinazione dell’azoto totale con analizzatore elementare p. 284 3. Determinazione dell’azoto totale con metodo semi-micro-Kjeldahl p. 284 4. Determinazione dell’azoto totale con metodo semi-micro-Kjeldahl modificato p. 287 5. Determinazione dell’azoto totale estraibile con soluzione salina con metodo micro-Kjeldahl p. 291 6. Determinazione dell’azoto totale estraibile con soluzione salina con metodo micro-Kjeldahl modificato p.294 7. Determinazione colorimetrica degli ioni ammonio estraibili p. 296 8. Determinazione colorimetrica degli ioni nitrato estraibili p. 298 9. Estrazione dell’azoto totale idrolizzabile con acido cloridrico p. 300 10.Determinazione dell…
Soil enzyme assays using p-nitrophenyl derivatives: an inter-laboratory comparison
Reproducibility and reliability of soil enzyme assays need to be validated by comparing results among different labs. The Italian Group of Enzymology organized a ring test among five labs. Beta-glucosidase, acid- and alkaline phosphatase activities were chosen as they are all measurable by using substrates with wide applicability, i.e. p-nitrophenyl derivatives. The five labs preliminarily agreed and standardised the specific methodological procedure for each enzymatic activity, also taking into account factors such as practicability and equipment availability. Nine soils with contrasting physico- chemical and biological properties were adequately sampled, pre-treated and sieved, in order t…