GB/T 5918-2008 Determination of mixing homogeneity for feed products
1 Scope
This standard specifies the two methods for determining the mixing homogeneity of feed products, namely chloride ion selective electrode method and methyl violet method.
This standard is applicable to the determination of mixing homogeneity of compound feeds, concentrated feeds and concentrate supplements, as well as the determination of mixing performance of mixers.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding any corrigendum), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the standards indicated below. For undated references, the latest edition applies.
GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-1992, neq ISO 3696:1987)
3 Chloride ion selective electrode method (arbitration method)
3.1 Principle
The content of chloride ion is determined by the selective response of the potential of chloride ion selective electrodes to chloride ions in the solution, and then the mixing homogeneity of feeds is reflected by the difference of chloride ion content in different samples in the same batch.
3.2 Reagents
Unless otherwise specified, the following reagents are of analytical grade. Water is distilled water, which meets the requirements of GB/T 6682 on Grade III water.
3.2.1 Nitric acid solution: pipette 35 mL of concentrated nitric acid and dilute it to 1,000 mL with water to make the solution with a concentration of about 0.5 mol/L.
3.2.2 Potassium nitrate solution: pipette 252.75g of potassium nitrate in a beaker, add water, heat it slightly, and dilute it to 1,000 mL with water to make the solution with a concentration of about 2.5 mol/L.
3.2.3 Chloride ion standard solution: Weigh 8.2440 g of sodium chloride cooled after being burning at 550 ℃ for 1h, place it into a beaker, add water to dissolve it by heating slightly, transfer it into a 1,000 mL volumetric flask, dilute to the mark with water, and shake well; the content of chloride ions in the solution is 5 mg/mL.
3.3 Apparatus
3.3.1 Chloride ion selective electrode.
3.3.2 Double salt bridge calomel electrode.
3.3.3 Acidity meter or potentiometer: with a precision of 0.2 mV.
3.3.4 Magnetic stirrer.
Contents
Foreword i
1 Scope
2 Normative References
3 Chloride ion selective electrode method (arbitration method)
4 Methyl violet method
GB/T 5918-2008 Determination of mixing homogeneity for feed products
1 Scope
This standard specifies the two methods for determining the mixing homogeneity of feed products, namely chloride ion selective electrode method and methyl violet method.
This standard is applicable to the determination of mixing homogeneity of compound feeds, concentrated feeds and concentrate supplements, as well as the determination of mixing performance of mixers.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding any corrigendum), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the standards indicated below. For undated references, the latest edition applies.
GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-1992, neq ISO 3696:1987)
3 Chloride ion selective electrode method (arbitration method)
3.1 Principle
The content of chloride ion is determined by the selective response of the potential of chloride ion selective electrodes to chloride ions in the solution, and then the mixing homogeneity of feeds is reflected by the difference of chloride ion content in different samples in the same batch.
3.2 Reagents
Unless otherwise specified, the following reagents are of analytical grade. Water is distilled water, which meets the requirements of GB/T 6682 on Grade III water.
3.2.1 Nitric acid solution: pipette 35 mL of concentrated nitric acid and dilute it to 1,000 mL with water to make the solution with a concentration of about 0.5 mol/L.
3.2.2 Potassium nitrate solution: pipette 252.75g of potassium nitrate in a beaker, add water, heat it slightly, and dilute it to 1,000 mL with water to make the solution with a concentration of about 2.5 mol/L.
3.2.3 Chloride ion standard solution: Weigh 8.2440 g of sodium chloride cooled after being burning at 550 ℃ for 1h, place it into a beaker, add water to dissolve it by heating slightly, transfer it into a 1,000 mL volumetric flask, dilute to the mark with water, and shake well; the content of chloride ions in the solution is 5 mg/mL.
3.3 Apparatus
3.3.1 Chloride ion selective electrode.
3.3.2 Double salt bridge calomel electrode.
3.3.3 Acidity meter or potentiometer: with a precision of 0.2 mV.
3.3.4 Magnetic stirrer.
Contents of GB/T 5918-2008
Contents
Foreword i
1 Scope
2 Normative References
3 Chloride ion selective electrode method (arbitration method)
4 Methyl violet method
