Dear all, I 'm so concerned, as we have often the same problem with some sediment wich are very poor in N (0.02%), so I'm really interesting in the answer, as I often doubt that we have a good combustion with 100 or 200mg sample. Ruben G. Chavez a écrit : >Dear all, > >I am analyzing SOIL NC in EA and I need at least 75ugN in the sample to get a >good linearity. With this amount of N I need, I need to weigh up to 200 mg of >finely ground sample due to low %N in the sample. Please help me on how to >know if I have a good combustion of the sample. Is there a specific >combustion catalyst for plant or soil combustion? > >Many thanks for your help. > > >Ruben G. Chavez >Officer >Analytical Service Laboratories >Mail: DAPO Box 7777, Metro Manila, Philippines >Tel: +63(2) 580-5600 ext. 2419 >Fax: +63(2) 580-5699 >Web: www.irri.org > > > -- Isabelle Billy UMR EPOC - 5805 Département de Géologie et Océanographie Université de Bordeaux I avenue des facultés 33405 TALENCE Cedex, France email [log in to unmask] tel. (33) 05 40 00 33 14 fax (33) 05 40 00 08 48