Analytisk kemi

Kommittébeteckning: SIS/TK 121 (Bestämning av mikrostruktur i stål)
Källa: ISO
Svarsdatum: den 20 aug 2020
Se merSe mindre
 

This document specifies a determination procedure of energy resolution in the scanning transmission electron microscope or the transmission electron microscope equipped with the electron energy loss (EEL) spectrometer.

This document is applicable to both in-column type EEL spectrometer and post-column type EEL spectrometer. These EEL signal detecting systems are applicable to a parallel detecting system and a serial detecting system.

Ämnesområden: Luftkvalitet; Kemisk analys
Kommittébeteckning: SIS/TK 423 (Luftkvalitet)
Källa: ISO
Svarsdatum: den 26 sep 2020
Se merSe mindre
 

This International Standard provides methods for

- calibration of an instrument with one or two calibration gas mixtures,

- determining the composition of a gas sample, and

- evaluating the uncertainty of the composition of the gas sample in relation to the uncertainty of the composition of the calibration gases used, and the contribution of the measurement process.

This International Standard sets requirements to, and acceptance criteria for, the utilization of different measurement calibration designs with a limited (i.e. minimum) number of calibration gas mixtures used in calibration.

The methods in this International Standard are described for amount-of-substance fractions, but are also applicable for other composition quantities (such as mass fractions, volume fractions, or concentrations).

Ämnesområden: Kemisk analys
Kommittébeteckning: SIS/TK 423 (Luftkvalitet)
Källa: ISO
Svarsdatum: den 26 sep 2020
Se merSe mindre
 

This part of ISO 6142 specifies a gravimetric method for the preparation of calibration gas mixtures in cylinders with traceable values for the amount-of-substance fraction (amount fraction) of one or more components. This part of ISO 6142 describes a method for calculating the uncertainty associated with the amount fraction of each component. This uncertainty calculation requires the evaluation of the contributions to the uncertainty due to factors including the weighing process, the purity of the components, the stability of the mixture, and the verification of the final mixture.

This part of ISO 6142 is only applicable to mixtures of gaseous or totally vaporized components, which may be introduced into the cylinder in the gaseous or liquid state. Both binary and multi-component gas mixtures (including natural-gas type mixtures) are covered by this part of ISO 6142. Methods for the batch production of more than one mixture in a single process are not included in this part of ISO 6142.

This part of ISO 6142 requires estimation of the stability of the mixture for its intended life time (maximum storage life), but it is not for use with components that react with each other unintentionally. This part of ISO 6142 also requires the impurities in each parent gas or liquid used in the preparation of the mixture to be assessed and quantified.