GB/T 7728-2021Chemical analysis of metallurgical products—General rule for flame atomic absorption spectrometric methods (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document replaces GB/T 7728-1987 "General Principles of Flame Atomic Absorption Spectrometry for Chemical Analysis of Metallurgical Products", and is in line with GB/T 7728-1987 Compared with 1987, in addition to structural adjustments and editorial changes, the main technical changes are as follows.

a) The "Scope of Application" is changed to "Scope", and the content is changed (see Chapter 1, Chapter 1 of the 1987 edition);

b) Added "Reagents and Materials" section (see Chapter 5);

c) The "Instrument" part has been added to specify the requirements of the instrument in detail (see Chapter 6);

d) The "Determination" part has been added, and detailed requirements for the selection of test preparation and determination conditions have been made (see Chapter 7);

e) Adjust the "Note" part of "Calibration Solution Preparation" to the main text (see Chapter 8, Chapter 5 of the 1987 edition);

f) Change "Instrument preparation and instrument performance judgment and requirements" to "Instrument preparation and performance requirements" (see Chapter 9, 1987 Chapter 6 of the Year Edition);

g) The value of k in the calculation formula of the detection limit of the instrument has been changed (see 9.3.3, 6.3.3 of the 1987 edition);

h) Change "calibration method, measurement and result calculation" to "quantitative analysis method" (see Chapter 10, Chapter 7 of the 1987 edition);

i) The formula for calculating the mass concentration of analytical elements in the "zero" calibration solution is changed (see 10.1.4, 7.1.3 in the 1987 edition);

j) Change the "high-precision measurement method" to "high-precision ratio method (matrix matching method)" (see 10.2, 1987 edition of 7.2);

k) Part of the "Standard Access Law" has been changed (see 10.3, 7.3 of the 1987 edition);

l) Added "Laboratory Environment Requirements" (see Chapter 11);

m) Added "High-pressure gas storage and use requirements" (see Chapter 12);

1 Scope

This document specifies the principles, reagents and materials, instrument composition, measurement methods, and methods of flame atomic absorption spectrometry for chemical analysis of metallurgical products.

Calibration solution preparation, instrument preparation and performance requirements, quantitative analysis methods, laboratory environment requirements.

This document is applicable to the application, research and personnel training of flame atomic absorption spectrometry for chemical analysis of metallurgical products.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 4470 Terminology for flame emission, atomic absorption and atomic fluorescence spectrometry

GB 4962 Hydrogen Safety Technical Regulations

GB/T 6682 Analytical laboratory water specifications and test methods

GB 6819 dissolved acetylene

3 Terms and definitions

The terms and definitions defined in GB/T 4470 are applicable to this document.

4 Principle

The sample solution is sprayed into the flame as a mist to atomize the element to be measured. The light radiated from the light source with the characteristic spectrum of the element to be tested passes the test When the vapor is sampled, it is absorbed by the ground state atom of the element to be measured in the vapor, and the absorbed part is positive to the concentration of the atom in the flame under certain conditions. Compare. The content of the element to be measured in the sample is determined according to the degree of weakening (absorption) of the characteristic spectrum of radiation. See the basic principles of atomic absorption Appendix A.

5 Reagents and materials