氯代十六烷基吡啶光度法测定水中硝基苯类化合物时,水样中()、()和()离子浓度很高时,会产生絮状沉淀,需要离心后再进行光度测定。
参考答案:铁;钙;镁
湿热型带下病的主证中,下列哪项是错误的()
A.带下量多,色黄或黄白
B.质粘腻,无臭气
C.胸闷口腻
D.阴部瘙痒
E.纳呆
Smell the flowers before you go to sleep,and you may just ______sweet dreams. [ ]
A. keep up with
B. put up with
C. end up with
D. catch up with