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Comparison of inert-gas-fusion and modified kjeldahl techniques for determination of nitrogen in niobium alloys
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Merkle, E. J. Davis, W. F. Graab, J. W. |
| Copyright Year | 1974 |
| Description | This report compares results obtained for the determination of nitrogen in a selected group of niobium-base alloys by the inert-gas-fusion and the Kjeldahl procedures. In the inert-gas-fusion procedure the sample is heated to approximately 2700 C in a helium atmosphere in a single-use graphite crucible. A platinum flux is used to facilitate melting of the sample. The Kjeldahl method consisted of a rapid decomposition with a mixture of hydrofluoric acid, phosphoric acid, and potassium chromate; distillation in the presence of sodium hydroxide; and highly sensitive spectrophotometry with nitroprusside-catalyzed indophenol. In the 30- to 80-ppm range, the relative standard deviation was 5 to 7 percent for the inert-gas-fusion procedure and 2 to 8 percent for the Kjeldahl procedure. The agreement of the nitrogen results obtained by the two techniques is considered satisfactory. |
| File Size | 494814 |
| Page Count | 15 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19740017919 |
| Archival Resource Key | ark:/13960/t44r2p06n |
| Language | English |
| Publisher Date | 1974-06-01 |
| Access Restriction | Open |
| Subject Keyword | Materials, Metallic Gas Chromatography Platinum Niobium Alloys Kjeldahl Method Experiment Design Gas Analysis Spectrophotometry Nitrogen Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
