GB/T 21994.1-2008Chemical analysis of magnesium fluoride - Part 1: Preparation and storage of test samples (English PDF)

Foreword

GB/T 21994 "Chemical analysis of magnesium fluoride" is divided into eight sections.

--- Part 1. Preparation and storage of test samples;

--- Part 2. Determination of the weight of water in the wet method;

--- Part 3. Determination of distillation of fluorine content - thorium nitrate volumetric method;

--- Part 4. Determination of magnesium content - EDTA volumetric method;

--- Part 5. Determination of calcium content by flame atomic absorption spectrometry;

--- Part 6. Determination of silicon dioxide content - Molybdenum blue spectrophotometric method;

--- Part 7. Determination of iron oxide content phenanthroline spectrophotometry;

--- Part 8. Determination of sulfate content of barium sulfate gravimetric method. This is Part 1. This part is proposed by the China Nonferrous Metals Industry Association. The non-ferrous metal part by the National Standardization Technical Committee. This section is Hunan Nonferrous fluorine chemical limited liability company, China Nonferrous Metals Industry Institute of Standards Metrology and Quality is responsible for drafting. This section is drafted. Hunan Nonferrous fluorine chemical limited liability company. Participated in the drafting of this section. Fluoride Chemicals Co., Ltd., Silver fluoride limited liability company. The main drafters of this section. Li Zhijian, Liao Zhihui, Chen Xiang Yu, Zhu Liang, Xu Jin Xue, Wang Jianping, Guo Xianhui, Bo, Li Ye. Chemical analysis of magnesium fluoride Part 1. Preparation and storage of test samples

1 Scope

GB/T 21994.1-2008 is the Chinese national standard on chemical analysis of magnesium fluoride - part 1: preparation and storage of test samples, in the field of metallurgy. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 9 June 2008 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 December 2008. Classification: ICS 77.040.30, CCS H12. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This section provides the sample preparation and storage of the original magnesium fluoride and dry sample. This section applies to the preparation and storage of the original sample and the magnesium fluoride dried sample.

2 Normative references

The following documents contain provisions which, through reference in this text, constitute provisions of this part. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this section, however, encourage the parties to this part of the research agreement Whether the latest versions of these documents. For undated references, the latest edition to adapt to this section.

GB/T 6679 General rules for sampling solid chemical products Preparation and storage of specimens 3

3.1 laboratory sample Using

GB/T 6679 stipulated in laboratory sample preparation and storage methods.

3.2 Preparation of the original sample For some geometric properties measured for testing certain physical and physico-chemical properties, as well as for determination of hygroscopic moisture. Take about 300g solid Laboratory sample (3.1), which was stored in a sealed container, the container is almost filled sample is appropriate.

3.3 Preparation of dry sample Chemical tests for the determination of certain geometrical characteristics and certain physical and chemical physics test.

3.3.1 Sample grinding The sample was milled and sieved until all of 0.125mm sieve pore size of up. Sieved sample mixed in 110 °C ± 5 °C drying 2h.