Protein is an important grade indicator of rice products. With the development of trade, the measurement of rice protein content has become more and more widely used in conformity assessment, and it has become increasingly important. KDN series Kjeldahl nitrogen analyzer is widely used in the content of nitrogen in seeds, grain, food, dairy products, beverages, feed, soil and other agricultural and sideline products. The accuracy and reliability of the measurement results directly affect the above products. Quality Evaluation. Recently, customers have more and more requirements for the calibration of nitrogen determination instruments. At present, there are no verification procedures or calibration standards for Kjeldahl analyzers in the country, which has brought considerable difficulties to the calibration of such instruments. By studying the principle of the instrument and the actual use requirements of the user and referring to relevant domestic and foreign standards, a calibration method for Kjeldahl apparatus is proposed. Kjeldahl is an instrument designed according to Kjeldahl method for determining the total nitrogen in a compound or mixture. The items that need to be calibrated before use are blank test, determination of recovery rate, measurement repeatability of the instrument. Here's how to calibrate the Kjeldahl analyzer. The blank test can check the stability of the instrument and eliminate impurities nitrogen interference. Blank test method: Weigh approximately 05g of sucrose (without nitrogen) in place of the sample, perform a blank determination according to the assay procedure, and measure twice in a row. The average volume of the standard titration solution consumed should not exceed 0.2mL. The determination of the recovery rate can directly reflect the accuracy of Kjeldahl measurement results. With the characteristics of stable and non-digestible nitrogen content of ammonium salt, the recovery rate can be determined simply and quickly. Recovery rate determination method: high-purity ammonium sulfate was dried at 105 degrees Celsius for 2 hours, 0.2 g (accurate to 0.1 mg) was weighed into a digestion flask, distilled, titrated, and the nitrogen content was calculated according to the equation. The measurement repeatability of the instrument can verify the reliability of the measurement results and is an indispensable calibration item. Weigh 0.2g of high-purity ammonium sulfate after drying. Distill and titrate according to the operation procedure. Calculate the recovery rate according to the equation and repeat the test six times with less result error.
1, Commodity: cold rolled Zinc Coated hot dipped Galvanized Steel strip/coil/banding/belt
2, Standards: GB700-88 and GB/T 8164-1993
3, Material Grade: Q195,Q195L,Q215,Q235,SPHC,SPHD,08AL,SS300,SS400,SS490,etc
4, Thickness: 0.14-1.5mm (+-0.02mm)
6, Zinc coating: Z30-100g/m2
7, Surface treatment: (non) Chromated,( 1965170,un)Oiled,Minimized spangle,
Regular spangle, Skin-passed,Non skinpassed
8, Coil weight: baby coil weight 300~1000KG, each pallet weight below 3000KG
or as client`s requirement
9, Coil ID: 508/610mm
10, Quality: No Joint, No Bends, no spots, no roller marks.
Cold Rolled Steel Coil,Steel Coil,Cold Rolled Steel,Cold Roled Coil WENZHOU ICL INDUSTRIAL CO., LTD. , https://www.cniclsteel.com
5, Width: 30-600mm (+-2mm)