title: Technical aspects concerning the detection of animal waste nutrient content via its electrical characteristics.
abstract: The variables influencing corrosion of three metals (galvanised steel, stainless steel, brass) usable for a manure nutrient probe were examined, identifying the best material for field applications. The nutrients in 18 liquid manures were then estimated through the voltage drop between the terminals of a prototype probe. Response Surface Modelling gave the regression functions relating each investigated response only to the statistically-significant factors. After 168h in the manure, it was determined that: stainless steel was the most suitable material for very close electrodes (mass: -1.8% at 15mm), brass can be used with any inter-electrode distance (mass: -13.0% maximum at 35mm). The prototype probe gave reliable estimates (R(2)⩾0.744) of Ntot, Namm, Ptot, Ktot when dry matter and temperature were also accounted for in the regression analysis. Not considering dry matter but just electronically-detectable quantities (temperature, voltage drop), the estimates were only reliable (R(2)⩾0.656) above 20°C.
authors: University of Padova, Department of Land, Environment, Agriculture and Forestry - TeSAF, Section of Mechanization, Construction and Plant Engineering, viale dell'Università 16, I-35020 Legnaro (PD), Italy. marco.bietresato@unipd.it
authors: Marco
authors: M
authors: Bietresato
authors: Luigi
authors: L
authors: Sartori
mesh_terms: D000818:Animals; D002417:Cattle; D003300:Copper / Q000737:chemistry*; D003343:Corrosion; D004553:Electric Conductivity; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D005502:Food; D007558:Italy; D008372:Manure / Q000032:analysis*; D012044:Regression Analysis; D013193:Stainless Steel / Q000737:chemistry*; D013232:Steel / Q000737:chemistry*; D034421:Sus scrofa; D015032:Zinc / Q000737:chemistry*
chemical_list: D008372:Manure; D013193:Stainless Steel; D013232:Steel; C048399:brass; D003300:Copper; D015032:Zinc