Analytisk kemi

Kommittébeteckning: SIS/TK 121 (Bestämning av mikrostruktur i stål)
Källa: ISO
Svarsdatum: den 20 nov 2019
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This International Standard describes procedures for measuring average grain size derived from a two-dimensional polished cross-section using electron backscatter diffraction (EBSD). This requires the measurement of orientation, misorientation and pattern quality factor as a function of position in the crystalline specimen[1].

NOTE 1 While conventional methods for grain size determination using optical microscopy are well-established, EBSD methods offer a number of advantages over these techniques, including increased spatial resolution and quantitative description of the orientation of the grains.

NOTE 2 The measurements in this standard are made on two dimensional sections. The reader should note carefully the definitions used (section 3.3) which draw a distinction between the measured sectional grain sizes, and the mean grain size which can be derived from them that relates to the three dimensional grain size.

NOTE 3 The method also lends itself to the measurement of the grain size of complex materials, for example those with a significant duplex content.

NOTE 4 The reader is warned to interpret the results with care when attempting to investigate specimens with high levels of deformation.

Ämnesområden: Kemisk analys
Kommittébeteckning: SIS/TK 423 (Luftkvalitet)
Källa: CEN
Svarsdatum: den 17 dec 2019
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This International Standard specifies minimum requirements for the contents of certificates for homogeneous gas mixtures in gas cylinders to be used as calibration gas mixtures. Pure gases, when used as calibration gas mixtures, are also covered by this International Standard. Gases and gas mixtures produced for other purposes are not considered.

The requirements in this International Standard deal with the metrological aspects of calibration gas mixtures. Other aspects, such as safety and legislative aspects, are not covered.

Furthermore, it specifies additional information (optional data) recommended for describing a homogeneous gas mixture, supplied under pressure in a cylinder or other container. It does not cover the field of safety-relevant data and related labelling.