Data/hora: 17/06/2024 09:22:18

Biblioteca(s): 	Embrapa Instrumentação.	
Data corrente: 	21/01/2005	
Data da última atualização: 	08/03/2010	
Autoria: 	LEMOS, S. G.; NOGUEIRA, A. R. A.; TORRE-NETO, A.; PARRA, A.; ARTIGAS, J.; ALONSO, J.	
Título: 	In-soil potassium sensor system.	
Ano de publicação: 	2004	
Fonte/Imprenta: 	Journal of agricultural and food chemistry, v.52, 2004. p. 5810-5815.	
Idioma: 	Inglês	
Conteúdo: 	A potentiometric sensor system based on potassium ion-selective electrodes was developed for agricultural purposes. Sensors were built using PVC ion-selective membranes over an inner solid contact prepared with graphite-epoxy composites. A copper plate was used as a reference electrode. A Iwo-stage electronic circuit composed of current and voltage amplifiers was designed to interface lhe sensors to a distributed data acquisition system. Three ion-selective sensors and three off-the- shelf temperature sensors and their associated circuils were mounted in a PVC tube to seI up a soil probe. The electronic contrais were placed in an airtight box fixed at lhe upper part of lhe probe. The system was evaluated in lhe field, where lhe sensors presented sensibility within lhe range of 69- 71 mV dec-1. Extracts of soil samples were analyzed by a current lIame photometry approach, and the results, compared with the probe measurements, showed a linear relationship (r2 = 0.992 and 0.995, respectively, to 5 and 20 cm depths), which implies viability and instrumentation reliability for agricultural applications.	
Palavras-Chave: 	Força dos sensores.	
Thesagro: 	Análise do Solo; Fertilidade do Solo; Potássio.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Instrumentação (CNPDIA)	
Exemplares: 	CNPDIA - (8605-1) - UPC - SP - -- - PROCI-04.00093 -  - 2004.00093 - DIS