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Chemicals classification

Reasonable classification of chemical reagents due drafting of national standards has been far from satisfying the needs of scientific research and production, but also a serious impediment to the production of chemical reagents. Relying on the existing 227 national standards and industry standards, it is difficult to such a large number of chemical agents is given a quality specification; we can not all chemicals are given a national quality standards, or even a mention to the reagent, people first thought is analytically pure or chemically pure, even, people are buying, regardless of purpose, not "AR" do not buy. This is why many countries that do not have standard varieties, but somehow, there is no base to give the product a red label AR fraud reasons. But also because in actual use, many cases do not require real "AR", unscrupulous manufacturers of industrial products was deliberately add "AR" tab, confused purity level, although in most cases the quality will not be an accident, but but seriously interfere with the true "standard material, AR," the production and use.

Besides that, since a large number of conventional chemicals, but only 225 varieties divided into pure class distinctions, analytical grade or chemically pure, then what need it!

China and international distinction


Growing international tendency to follow the main content of the chemical, physical constants and other chemical agents to indicate the level and purity. Is generally believed that, when the main content, boiling point, melting point, density, refractive index, or UV, IR, NMR spectra are known, a purity of the substance, the scope of it can be fully determined. This is the main difference between our country and abroad, chemical reagents chemical reagents label label content.

In fact, the so-called chemical agents: is used in pharmaceutical chemistry experiment; that chemical experiments require chemicals. Chemical purity level division, you can come and go based on quality standards and determine the scope of chemicals.

classification


Accordingly, the chemical reagent grade 1 is divided into standard reagents, biochemical reagents, electronic reagents, laboratory reagents four categories.

Level 1 standard classification principles not only define quality standards, but also take into account the scope of application of the chemical agent.

Level 1 Level 2 standard is classified on the basis of further division, which is to further clarify and define Class 1 standards.

Level 3 primarily for comparison with the original old standard, or more accurately indicate the identified uses.

After grade 1 or 2 is determined, a quality indicator of chemical reagents, and application of quality indicators for this purpose can be applied also determined.

Therefore, I propose to examine as the analysis of the criteria and standards "standard reagent" quality standards give clear national standards be published. Rest "biochemical reagents, electronic reagents, laboratory reagents" quality indicators can follow corporate standards, or update the increasingly technological requirements determined by the market on their own, so that we can get out of the original chemical reagents industry "dead set" of the old frame, development flourish!

Standard reagent BZ: according to international norms and technical requirements in order to identify as a standard substance analysis arbitration.

Biochemical reagents SH: preparation of biochemistry and biochemical synthesis.

Electronic reagent DZ: generally refers to chemicals and materials used in the electronic information industry, including integrated circuits and discrete devices chemicals, printed circuit board supporting chemicals, chemicals and surface mount display and other chemicals.

Reagents SY: according to the "main content" to determine "synthetic reagent." Reagents for chemical synthesis in the laboratory, isolated and purified to meet the general requirements of synthesis reagents.