测砷的样品预处理法中的干灰化法,在样品中加入助灰化剂。下列操作中最合理的是( )。...
Thursday, September 22, 2022
测定食品中的硒,消化处理至终点冷却后,为使六价硒还原成四价硒,需要加入以下哪种物质后继续加热()...
Thursday, September 22, 2022
Friday, September 16, 2022
Thursday, September 22, 2022
Thursday, September 22, 2022
单选题适用于一般化学分析的试剂标签颜色是( )。A B C D E...
Monday, August 14, 2023
当溶解性总固体大于1000mg/L时,应采用下列何种温度范围烘烤?在此温度下,矿物质中含有的吸着水都可除去,重碳酸盐均转...
Friday, September 16, 2022
用固体吸附剂采样管采样,采到什么程度被认为是“穿透”了?( )...
Thursday, September 22, 2022
还原后的水样应立即加入0.5ml对氨基苯磺酰胺试剂,摇匀后()内加入0.5ml盐酸N—1—萘基—乙烯二胺试剂,放置10m...
Tuesday, September 20, 2022
Thursday, September 22, 2022
Thursday, September 22, 2022
用重铬酸钾标定硫代硫酸钠溶液时,以下操作步骤中,错误的是( )。...
Thursday, September 22, 2022
Thursday, September 22, 2022
采集颗粒物前,玻璃纤维滤膜必须经高温炉灼烧,之后放于天平室的干燥器中平衡灼烧的温度和平衡的时间为()...
Thursday, September 22, 2022
高效液相色谱法测定水中苯并(a)芘,样品处理液中常含有极性化合物,干扰测定,处理的办法是()...
Thursday, September 22, 2022
Saturday, September 17, 2022
Saturday, September 17, 2022
Thursday, September 22, 2022
在临床检验中,药物敏感度的测定方法中最常用的方法是()...
Sunday, September 18, 2022