【单选题】阿司匹林中检查游离水杨酸的方法为:取本品0.1g,加乙醇1ml溶解后,加水使成50ml,立即加新配制的稀硫酸铁铵试液1ml,30s内如显色,与水杨酸对照液(0.1mg/ml)1ml同法制备溶液比较,颜色不得更深。其游离水杨酸的限量为( )。
【单选题】关于糖尿病的运动治疗,错误的是:( )
C.
要遵循因人而异,量力而行,循序渐进,持之以恒
【单选题】This is one of the best books ______ on the subject.
A.
that have ever been written
B.
which have ever been written
C.
that has ever been written
D.
whatever have been written
【单选题】This is the one of the longest bridges that ______ on the river.
【单选题】This is the (longest) flight I (have ever taken). By the time we get to Los Angeles, we (had flown) (for) 9 hours.
【判断题】四氯乙烯分子在红外光谱上没有 υ(C=C)吸收带。
【单选题】阿司匹林中检查游离水杨酸的方法为:取本品0.1g,加乙醇lml溶解后,加水使成50ml,立即加新配制的稀硫酸铁铵试液1ml,30s内如显色,与水杨酸对照液(0.1mg/ml)lml同法制备溶液比较,颜色不得更深。其游离水杨酸的限量为
【判断题】四氯乙烯分子在红外光谱上没有υ(C=C)吸收带。( )
【单选题】关于糖尿病的运动治疗,错误的是:( )
C.
要遵循因人而异,量力而行,循序渐进,持之以恒