This standard specifies the determination method and result calculation of the thousand-grain weight of grains and oilseeds. This standard is applicable to the determination of the thousand-grain weight of commercial grains and oilseeds. GB 5519-1988 Method for determination of the thousand-grain weight of grains and oilseeds GB5519-1988 Standard download decompression password: www.bzxz.net
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National Standard of the People's Republic of China Cereals and oilseeds rnethod for determinationof the mass of 1000 grains This standard refers to the international standard ISO 520--1977 "Method for determination of dry grain weight of cereals and legumes". Subject content and scope of application This standard specifies the determination method and result calculation of dry grain weight of grains and oilseeds. This standard is applicable to the determination of dry grain weight of commercial grains and oilseeds. 2 Definitionswww.bzxz.net 2.1 Natural moisture dry grain weight refers to the dry grain weight including moisture when measuring. 2.2 Dry basis dry grain weight refers to the dry grain weight after correcting the moisture content when measuring. 3 Principle UDC 633. 1+-663 .85:531 GB5519 Replaces GB5519--85 Count the whole kernels in the sample and weigh them. Divide the weight of the whole kernels by the number of kernels and express the result as the weight corresponding to 1000 kernels. 4 Apparatus and equipment 4.1 Balance: with a sensitivity of 0.01 g. 4.2 Grain counter. If no suitable counter is available, the counting can also be done manually. 4.3 Analysis tray, tweezers, etc. 5 Operating steps 5.1 Determination of 1000-kernel weight of natural moisture After removing impurities from the sample, divide the sample into approximately 500 kernels using a sample divider or quartering method, pick out the whole kernels, count the number of kernels, weigh them accurately, and convert them into the weight of 1000 kernels. 5.2 Determination of dry grain weight on dry basis Dry grain weight on dry basis, the moisture content of the sample shall be determined according to GB5497-85 "Determination of moisture content in grains and oilseeds", and the dry grain weight shall be determined according to 5.1. Each sample shall be determined twice. 6 Expression of results 6.1 Calculation method 6.1.1 Natural moisture dry grain weight is obtained by formula (1): m. ×1000 Dry grain weight= Where: ma- Sample mass, 8; Approved by the Ministry of Commerce of the People's Republic of China on July 6, 1988 (1) Implemented on March 1, 1989 Number of grains in the sample. GB5519—88 6.1.2 Thousand-grain weight of dry sample, obtained by formula (2): Dry-grain weight = Grain weight × (100- M) 100 Wherein: M-moisture content of sample, %. 6.1.3 If the parallel determination results meet the allowable difference requirements, the arithmetic mean shall be taken as the result. Otherwise, re-sampling shall be performed and the result shall be expressed in units of 1000-grain weight. For thousand-grain weight less than 10g, two decimal places shall be retained; for dry grain weight equal to or greater than 10g but not exceeding 100g, one decimal place shall be retained; for dry grain weight greater than 100g, an integer shall be taken. The difference between the results of two simultaneous or consecutive determinations shall not exceed 6% for dry grain weight greater than 25g and 10% for other dry grain weights. Additional Notes: This standard is under the jurisdiction of the Grain Storage and Transportation Bureau of the Ministry of Commerce of the People's Republic of China. This standard was drafted by the Grain Oil Chemistry Research Institute of the Ministry of Commerce. The main drafter of this standard is Ma Yulian. Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.