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QB/T 5015-2016 PDF EnglishUS$90.00 · In stock · Download in 9 seconds
QB/T 5015-2016: The determination of a- amino nitrogen in sugar beet Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure Status: Valid
Excerpted PDFsFull copy of true-PDF will be delivered in 9 seconds upon purchase: QB/T 5015-2016Similar standardsYY/T 0681.18 GB/T 317 QB/T 5007QB/T 5015-2016: The determination of a- amino nitrogen in sugar beet---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/QBT5015-2016QB LIGHT INDUSTRY STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 67.180 Classification No.: X30 Filing No.: 55590-2016 The determination of α-amino nitrogen in sugar beet ISSUED ON: JULY 11, 2016 IMPLEMENTED ON: JANUARY 01, 2017 Issued by: Ministry of Industry and Information Technology of PRC Table of ContentsForeword ... 3 1 Scope ... 4 2 Normative references ... 4 3 Principle ... 4 4 Reagent ... 4 5 Instruments ... 5 6 Sample preparation ... 5 7 Determination ... 6 8 Calculation ... 6 9 Precision ... 7 The determination of α-amino nitrogen in sugar beet1 ScopeThis standard specifies the determination method for α-amino nitrogen in sugar beet. This standard applies to the determination of α-amino nitrogen in sugar beet.2 Normative referencesThe following documents are essential to the application of this document. For the dated documents, only the versions with the dates indicated are applicable to this document; for the undated documents, only the latest version (including all the amendments) are applicable to this standard. GB/T 6682 Water for analytical laboratory use - Specification and test methods3 PrincipleIn a slightly acidic (pH 6.0) copper salt solution, α-amino nitrogen forms a blue complex with copper ions; the depth of the blue color is proportional to the content of α-amino nitrogen. It is subject to colorimetric quantitation at a wavelength of 580 nm, to determine the content of α-amino nitrogen.4 ReagentUnless otherwise specified, all reagents used are of analytical pure. 4.1 Water It shall meet the requirements of grade-3 water in GB/T 6682. 4.2 Alkaline lead acetate solution Basic lead acetate solution: The density is (1.24 ± 0.01) g/mL; each 100 mL contains 9.5 g ~ 10.5 g of alkaline lead salt (calculated as PbO). 4.3 Diluted basic lead acetate solution balance which has a balance of 0.01 g. Transfer the mixture of the beet paste and the paste paper to the high-speed tissue masher. Add (177.0 ± 0.35) mL of basic lead acetate dilute solution (4.3). Cover the masher. Turn on the stirring motor. Dip it at 12000 r/min ~ 15000 r/min for 3 min (temperature 20 °C). Filter it. Take a clear solution to prepare for use.7 DeterminationAccurately pipette 50 mL of the sample extract into a 100 mL volumetric flask. Use distilled water to dissolve it and make the volume reach to the mark. Then pipette 25 mL of the solution into a 250 mL beaker. Pipette 0 mL, 5 mL, 10 mL, 20 mL, 30 mL, 40 mL, 50 mL, respectively, of standard amino nitrogen solution in a 100 mL volumetric flask. Use distilled water to dissolve and make its volume reach to the mark. These solutions respectively contain α-amino nitrogen of 0 mg/100 mL, 1.3 mg/100 mL, 2.6 mg/100 mL, 5.2 mg/100 mL, 7.8 mg/100 mL, 10.4 mg/100 mL, 13 mg/100 mL, respectively. Pipette 25 mL of the standard solution into a 250 mL beaker. Add 25 mL sodium acetate solution and 10 mL copper reagent to the test solution and standard solution, respectively. After mixing, use a 5 cm cuvette to adjust the zero point with distilled water. At a wavelength of 580 nm, measure the absorbance and draw a standard curve for comparison .8 CalculationThe formula for calculating the content of α-amino nitrogen in the specimen: Where: X - The content of α-amino nitrogen in the specimen, in milligrams per hundred grams (mg/100 g) A - The mass of α-amino nitrogen in the sample solution for determination, in milligrams (mg); m - The mass of the specimen, in grams (g). It is expressed as the arithmetic mean of two independent determination results obtained under repeatability conditions, retaining 3 significant digits. ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al. |