| Full text | |
| Author(s): |
Silva, Claudineia R.
[1]
;
Oliveira, Eliezer
[1]
;
Zagatto, Elias A. G.
[1]
;
Henriquez, Camelia
[1]
Total Authors: 4
|
| Affiliation: | [1] Univ Sao Paulo, Ctr Nucl Energy Agr, Piracicaba, SP - Brazil
Total Affiliations: 1
|
| Document type: | Journal article |
| Source: | Talanta; v. 158, p. 14-20, SEP 1 2016. |
| Web of Science Citations: | 0 |
| Abstract | |
A flow-based strategy involving a gas-diffusion sampling probe was proposed for evaluating the respiration rate in soils. The amount of CO2 collected after a pre-defined time interval was proportional to the free CO2 released by the soil ecosystem. The 500-mL incubation flasks typically used for soil respirometric assays were adapted and a special cover was designed for connecting a tubular gas diffusion membrane, a fan, and a septum for adding the CO2(g) standards required for calibration. The method relied on the pH-dependent absorbance variations resulting from the CO2 collection. A 1.3 mmol L-1 bromothymol blue solution (pH 7.0) acted as both acceptor and carrier streams. In order to widen the dynamical working range to 0.003-0.2 mmol CO2, two analytical curves were obtained, each related to a different time interval for the CO2 collection. Kinetic curves related to CO2 release by the soil samples were straightforwardly attained. Repeatability and detection limit were estimated as 2.0% and 0.001 mmol CO2 (n=10), and accuracy was assessed in relation to a recommended titrimetric procedure. (C) 2016 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 13/22927-9 - Advanced oxidation processes in flow analysis. |
| Grantee: | Carla Cripa Crispino Kamogawa |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |