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Registro Completo |
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Biblioteca(s): |
Embrapa Solos. |
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Data corrente: |
22/11/2002 |
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Data da última atualização: |
22/11/2002 |
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Autoria: |
TEDESCO, M. J. |
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Título: |
I. Analysis of 15N: evaluation of sample preparation and analysis methology with an optical 15N analyzer. II. The fate of urea fertilizer in some soils of Rio Grande do Sul, Brazil. |
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Ano de publicação: |
1972 |
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Fonte/Imprenta: |
s.l.: University of Wisconsin, 1972. |
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Páginas: |
127p. |
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Idioma: |
Inglês |
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Notas: |
Ph.D. Thesis. |
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Conteúdo: |
A comercially available optical 15N analyzer and sample preparation unit were evaluated with respect to ease of use, sample size, reproducibility and accuracy. The sample prep unit, which utilized a Dumas combustion approach to produce N2, was modified extensively and the hypobromite oxidation method for N2 production was adopted. Instrumentation problems and source of error include monlinear gain settings, baseline determination, overlapping peak heights and monlinear gain settings, baseline determination, overlapping peak heights and monlinearity of the standard curve. Problems in the sample method adopted were limited to memory in the discharge tube. This was reduced by prolonged heating of the tubes at 700 oC. Minimum sample size is about 10 ug of N. In the normal abundance to 5 atom % 15N range, the methid gave 0.01 confidence interval values of +- 0.031 atom % 15N. The analyzer was simple, rapid and free of downtime relative to most mass spectrometers. Transformation of pelleted 2.92 atmo % 15N urea fertilizer when applied 2 cm from the surface at the rate of 200 ppm in four acid Brazilian soils was studied. Each experimental unit was enclosed in a plexiglass chamber with controlled aeration, allowing determination of the NH3 and NO2 volatilized. The effects of cropping to ryegrass and liming were evaluated. Fertilizer N volatization losse as NH3 and NO2 could account at the most for only 2% of the N added. While no relationship was observed for NH3 volatilized, NO2 collected was greater for the ............. MenosA comercially available optical 15N analyzer and sample preparation unit were evaluated with respect to ease of use, sample size, reproducibility and accuracy. The sample prep unit, which utilized a Dumas combustion approach to produce N2, was modified extensively and the hypobromite oxidation method for N2 production was adopted. Instrumentation problems and source of error include monlinear gain settings, baseline determination, overlapping peak heights and monlinear gain settings, baseline determination, overlapping peak heights and monlinearity of the standard curve. Problems in the sample method adopted were limited to memory in the discharge tube. This was reduced by prolonged heating of the tubes at 700 oC. Minimum sample size is about 10 ug of N. In the normal abundance to 5 atom % 15N range, the methid gave 0.01 confidence interval values of +- 0.031 atom % 15N. The analyzer was simple, rapid and free of downtime relative to most mass spectrometers. Transformation of pelleted 2.92 atmo % 15N urea fertilizer when applied 2 cm from the surface at the rate of 200 ppm in four acid Brazilian soils was studied. Each experimental unit was enclosed in a plexiglass chamber with controlled aeration, allowing determination of the NH3 and NO2 volatilized. The effects of cropping to ryegrass and liming were evaluated. Fertilizer N volatization losse as NH3 and NO2 could account at the most for only 2% of the N added. While no relationship was observed for NH3 volatilized, NO2 co... Mostrar Tudo |
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Categoria do assunto: |
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Marc: |
LEADER 02012nam a2200133 a 4500
001 1331511
005 2002-11-22
008 1972 bl uuuu m 00u1 u #d
100 1 $aTEDESCO, M. J.
245 $aI. Analysis of 15N$bevaluation of sample preparation and analysis methology with an optical 15N analyzer. II. The fate of urea fertilizer in some soils of Rio Grande do Sul, Brazil.
260 $as.l.: University of Wisconsin$c1972
300 $a127p.
500 $aPh.D. Thesis.
520 $aA comercially available optical 15N analyzer and sample preparation unit were evaluated with respect to ease of use, sample size, reproducibility and accuracy. The sample prep unit, which utilized a Dumas combustion approach to produce N2, was modified extensively and the hypobromite oxidation method for N2 production was adopted. Instrumentation problems and source of error include monlinear gain settings, baseline determination, overlapping peak heights and monlinear gain settings, baseline determination, overlapping peak heights and monlinearity of the standard curve. Problems in the sample method adopted were limited to memory in the discharge tube. This was reduced by prolonged heating of the tubes at 700 oC. Minimum sample size is about 10 ug of N. In the normal abundance to 5 atom % 15N range, the methid gave 0.01 confidence interval values of +- 0.031 atom % 15N. The analyzer was simple, rapid and free of downtime relative to most mass spectrometers. Transformation of pelleted 2.92 atmo % 15N urea fertilizer when applied 2 cm from the surface at the rate of 200 ppm in four acid Brazilian soils was studied. Each experimental unit was enclosed in a plexiglass chamber with controlled aeration, allowing determination of the NH3 and NO2 volatilized. The effects of cropping to ryegrass and liming were evaluated. Fertilizer N volatization losse as NH3 and NO2 could account at the most for only 2% of the N added. While no relationship was observed for NH3 volatilized, NO2 collected was greater for the .............
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| 1. |  | ROUWS, L. F. M.; JESUS, E. da C.; MERCANTE, F. M.; MATTOS, M. L. T.; ZILLI, J. E. Validação de estirpes de rizóbio para a inoculação de espécies arbóreas, adubos verdes e forrageiras visando metas do programa ABC e do novo código florestal. In: REUNIÃO DA REDE DE LABORATÓRIOS PARA A RECOMENDAÇÃO, PADRONIZAÇÃO E DIFUSÃO DE TECNOLOGIAS DE INOCULANTES MICROBIANOS DE INTERESSE AGRÍCOLA, 17., 2014, Londrina. Anais... Londrina: Embrapa Soja, 2016. p. 78-79. 112 p. (Embrapa Soja. Documentos, 369). Editado por: Mariangela Hungria, Fábio Martins Mercante. RELARE 2014. (Embrapa Soja. Documentos, 369).| Tipo: Artigo em Anais de Congresso |
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