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1、w - International Standard INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.MEIKYHAPOHAR OPI-AHM3AL the- column is connected in series to a gas scrubber containing concentrated sulphuric acid, which is in turn connected to the air inlet of the drying oven. 3.6 Desiccator, containing an efficient desic
2、cant. 4 Procedure 4.1 Preparation of the test Sample Mix the Sample thoroughly and rapidly by stirring with a spatula in the Sample Container. If the Sample Container is too small for this purpose, transfer the entire Sample to another pre-dried Container of a suitable size to facilitate mixing. 4.2
3、 Preparation of the dish Place the open dish (3.2) and its lid in the oven (3.31, controlled at 100 OC for 1 h. Allow to cool to room temperature in the desiccator (3.6) and weigh to the nearest 0,000 2 g. 4.3 Test Portion Place about 10 g of anhydrous dextrose or about 5 g of dex- trose monohydrate
4、, in the dish (3.2), fit the lid and weigh to the nearest 0,000 2 g. 4.4 Determination Place the covered dish (3.2) containing the test Portion (4.3) in the oven (3.3) maintained at 100 k- 1 OC, remove the lid and leave it in the oven. Leave at the test temperature for 4 h, main- taining the pressur
5、e in the oven at not more than 135 mbar. During drying, draw a slow stream of air through the drying train (3.5) into the oven. After 4 h, shut off the vacuum pump (3.4) and allow air to slowly enter the oven through the drying train until atmospheric pressure is obtained. Before withdrawing the dis
6、h from the oven, fit the cover. Place the covered dish in the desiccator (3.61, allow to cool to room temperature, and weigh to the nearest 0,000 2 g. DO not put more than four dishes in the desiccator (3.6) at the same time. Carry out two determinations on the same test Sample (4.1). NOTE - If, dur
7、ing or after the test, the material develops a more or less pronounced yellow colour, repeat the test at a lower temperature, and state this in the test report. * 1 mbar = 0,l kPa Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical
8、Standards 1/9972545001 Not for Resale, 04/25/2007 20:46:53 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 1741-1980 (E) 5 Expression of results The loss in mass on drying, expressed as a percentage by mass of the product as received, is equal to 100 im, - m2) x m1 - mo
9、 where m. is the mass, in grams, of the dish and cover (4.2); ml is the mass, in grams, of the dish and cover and the test Portion before drying (4.3); m2 is the mass, in grams, of the dish and cover and the test Portion after drying (4.4). Take as the tions. result the arithmetic mean of the two de
10、termina- 6 Test report The test report shall indicate the method used and the result obtained. lt shall also mention all operating conditions not specified in this International Standard, or regarded as op- tional, as well as any circumstances that may have influenced the result. The report shall in
11、clude tification of the Sample. all details required for complete iden- 2 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/25/2007 20:46:53 MDTNo reproduction or networking permitted without license from IHS -,-,-