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How Temperature Affects Viscosity

  How Temperature Affects Viscosity: Viscosity can be defined as the internal friction that occurs as a material flow, relative to itself....

2018年2月28日星期三

Requirements for Detection of parallel samples

1. UV. Determination of the content required for the test two, if the control method, the reference also requires two, the absorption coefficient method is also two. The deviation of each result from the average value is within 0.5%.
2. Atomic Absorption. In the case of a quantitative test, two aliquots are prepared for each test sample, three times for each injection. RSD should not be more than 3%, graphite furnace properly relaxed, large dispersion can be measured several times to increase the reliability of the reading. 3% here, I personally consider it a RSD requirement of three injections per sample instead of a parallel sample. I do not know what people think.
3. Fluorescence analysis. parallel samples need to be done, the results of the average deviation within ± 1.5%.
4. Melting point detection. Each test at least 3 repeated measurements, 3 readings within 0.5 degrees to poor. If the test three times the difference between exceeding 0.5 ℃, or the average margin in the edge, the need to re-test twice, according to the average of five times the correction value calculation results. Melting point standard to be measured twice, the difference is less than 0.3%.
5. Pour point. need to be measured twice, but no bias limit requirements.
6. Polarimetry. Determination of specific rotation than the same sample and the blank each measured three times, take the average. Determination of content required parallel samples, and two parallel samples within the range of 0.02 °.
7. Refraction. Requirements of the same sample and blank each measured three times.
8. Viscosity.
8.1 Ping Viscometer. Prepare two parallel samples each measured three times, and these three measurements shall not exceed the average value of 5%.
8.2 Rotary Viscometer. No requirement.
8.3 Ubbelohde Viscometer. Prepare two parallel samples each measured twice, and these two measurements shall not exceed 0.1S. The results for both samples do not exceed 1% of the average, if more than two additional retestings are required.
9. PH. Prepare a sample and measure it twice, with a difference of no more than 0.1
10. Non-aqueous titration. The test should be not less than 2 copies. The direct use of perchloric acid raw material titration, the relative deviation of not more than 0.2%. Alkali titration solution titration, the relative deviation of not more than 0.3%. Preparations need to be extracted or evaporated to dry titration, the relative deviation of not more than 0.5%. Such as extracting the washing operation is complex, the relative deviation of not more than 1.0%.
11. Nitrogen content. for the test sample should be determined 2 copies, the constant nitrogen relative deviation should not exceed 0.5%. Semi-trace nitrogen relative deviation of not more than 1.0%.
12. Determination of ethanol (gas phase method). two copies of the test, the relative average deviation of not more than 2.0%.
13. hydroxyl value, iodine value, saponification value. parallel determination of 2 parts, the relative deviation of not more than 0.3%.
14. acid value, peroxide value. only a measure.

Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
Skype: kenyuan9023   Wechat/WhatsApp:+86 15068109723lei@zonwon.com  www.zonwontech.com