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Sywan金虫 (小有名气)
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[求助]
各位高手请帮忙翻译两段话，谢谢！
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Prepare a 0.4% w/v solution of sodium sulfide. Standardise this solution in the following manner. To 25 mL of 0.05M iodine VS add 8 mL of hydrochloric acid and 25 mL of the sodium sulfide solution. Titrate with 0.1M sodium thiosulfate solution VS using starch solution, added towards the end point, as indicator. Repeat the operation without the sodium sulfide solution. The concentration of the sodium sulfide solution expressed in parts per million of hydrogen sulfide is the difference between the titrations multiplied by 68.16. Prepare a solution containing the equivalent of 20 ppm of hydrogen sulfide by appropriate dilution of the sodium sulfide solution with water. Repeat the procedure carried out on the injection using 2 mL of the 20-ppm hydrogen sulfide solution in place of the injection being examined. The absorbance of the solution obtained from the injection is not greater than the absorbance of the solution obtained from the standard (100 ppm with reference to the content of acetylcysteine). |
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