应版主的要求,再编辑一下,大家有什么意见或建议,欢迎随便讨论部分化学测试简要步骤,以下面样品为例: Brief procedure of some chemical test, takethe sample below as an example:一、甲醛(HCHO)含量的测试步骤:Procedureof Formaldehyde (HCHO) analysis:1. 把样品剪碎如下:cut two test specimens into small pieces as below:2. 称取平行样各2g,精确到10mg,并装入250ml的带塞锥形瓶中。weigh approximately 2 g of the pieces to an accuracy of 10 mg, for eachtest specimen, put the weighed pieces into a 250 ml flask with a stopper.
3. 在锥形瓶中加入100ml超纯水,放入水浴中。在40℃下震荡1小时Add 100 ml of water intoeach flask, stop tightly and place in a water bath at (40 ±2)°C for (60 ± 5) min. Shake the flask at least every 5 min, ensuring that the specimensare entirely wet.
4. 震荡完毕后,立即取出过滤.Then filter the solution into another flask through a filter.
5. 将样品溶液和显色剂(纳氏试剂)按1:1的比例混合,摇匀。Put 5 ml of the filtered test specimen solution in tubes, add 5 ml ofacetylacetone reagent into each tube and shake them.6. 然后放入40℃水浴中避光显色半小时,然后室温中放置半小时。Keep the test tubes first in a water bath at (40 ± 2)°C for (30 ± 5) min and then at ambient temperature for (30 ± 5)min.
7. 用紫外可见分光光度计,置溶液于10mm的比色皿中,在波长412nm处分析样品的吸光度。Using the UV-VIS spectrophotometer , measure the absorbances in a 10 mmabsorption cell at a wavelength of 412 nm.
二、八大重金属含量测试步骤:Procedureof Total Heavy Metal (8 elements) analysis:1. 称取剪碎的样品0.15g于消解罐中,加入10ml浓硝酸(在通风橱中),密封。Weigh a well-mixed sample near 0.15g into an appropriate vesselequipped with a pressure relief mechanism, add 10± 0.1 mL concentrated nitricacid(ina fume hood),then seal up.
2. 将消解罐放入微波设备中进行消解,过程大概2小时。Takeprepared vessels into microwavesystem that using microwave heating to digest samples. It will take near 2hours. 3. 消解完毕冷却后,将样品冲洗定容后,再过滤到小试管中,准备上机。After cooling, the vessel contents may be filtered, centrifuged, orallowed
to settle and then decanted, diluted to volume.4. 最后用ICP-OES分析其中重金属的含量Thenanalyze the total heavy metals by ICP-OES.若重金属含量超过限值,则需要做萃取测试,如下:Ifthe results of total heavy metals exceed the limits, it need to do a migrationtest.Belowis the procedure of migration test:1. 称取样品0.2g于50ml的锥形瓶中Weigh approximately 0.2 g of the pieces into a 25 ml flask.2. 加入10ml 0.07mol/L的盐酸溶液,在37℃水浴中震荡1小时,再静置1小时Add 10ml 0,07 mol/laqueous solution of hydrochloric acid, Agitate the mixture at (37 ±2) °C for 1h continuously and then allow to stand for 1 h at (37±2) °C.
3. 然后立即取出直接过滤到小试管中准备上机Without delay, efficiently separate the solids from the solution. Thesolution be filtered into tubes.4. 最后用ICP-OES分析其中重金属的含量Thenanalyze the heavy metals of migration by ICP-OES. End