01589nam a2200193 a 450000100080000000500110000800800410001910000260006024500850008626000810017152010280025265000110128065300150129165300170130665300140132365300160133770000220135370000200137510447682022-04-18       2000    bl uuuu     u00u1 u    #d1 aNOGUEIRA, A. R. de A.  aAcid vapor sample decomposition in open vessel microwave.h[electronic resource]  aIn: PITTCON, 21., 2000, New Orleans. Abstracts... New Orleans: PITTCONc2000  aMicrawave decomposition has been increasingly used hr a large number of samples. A method using an open vessel microwave was used for biological sample preparation with nitric acid vapors under atmospheric pressure. A lab made Teflon@ support suited with four cups, which received the samples, was inserted in the microwave vessel. These cups were used to weight 30 mg of certi5ed re5wence materials such as spinach and apple leaves, which received 150 pL of d.i. water to improve the micrawave e%ciency. This mixture was exposed to acid vapor stemmed from 15 mL of concentrated nitrie acid plsced in the bottom of the vessel hr decompoeition. The maximum microwave temperature, 115'C, was reached in 4 min. This condition was rnaintained hr 20 min to sllow complete decomposition of the sample. The deeomposed sample, in the cup, was diluted to 1.0 mL of d.i. water, shaken and centrifuged. The cups were than placed directed into an autosampler for Co and Fe analysis in an atomic absorption graphite fumace spectrometer.  acobalt  aAcid vapor  aDecompostion  aMicrovawe  aOpen vessel1 aARAÚJO, G. C. L.1 aNÓBREGA, J. A.