用高效液相色谱法测定一般护肤类化妆品中氢醌,已知标准溶液的出峰时间为3分51秒,如样

题型:单项选择题 A1/A2型题

问题:

用高效液相色谱法测定一般护肤类化妆品中氢醌,已知标准溶液的出峰时间为3分51秒,如样品液也在3分51秒有一流出峰,在下面5种措施中,最不可取的措施为()。

A.改变色谱柱,如仍为阳性结果,即可报告含有氢醌

B.改变流动相,如仍为阳性结果,即可报告含有氢醌

C.测定该峰流出物的紫外吸收光谱,如仍为阳性结果,即可报告含有氢醌

D.测定该峰流出物的质谱,如仍为阳性结果,即可报告含有氢醌

E.直接出含有氢醌的检验报告

考点:理化检验技术(师)专业知识专业知识题库
题型:单项选择题 A1/A2型题

广告最主要的形式因素是()

A.音乐

B.广告语言

C.画面图像

D.音响

题型:单项选择题 A1/A2型题
计算
(1)
(-5)2
+
-3
4
+1
+
-20
0.2
+(-
3
3
)-1

(2)先化简,再求值:(
3a
a-1
-
a
a+1
a
a2-1
,其中a=-1.
题型:单项选择题 A1/A2型题

ABC Limited is a private company limited by shares, which has adopted Table A as its articles of association. The authorised and issued share capital of ABC Limited is EUR 10,000 divided into 5,000 Class ‘A’ shares of EUR 1 each and 5,000 Class ‘B’ shares of EUR 1 each. Class ‘A’ shares enjoy preferential rights over dividends and repayment of capital. Mary holds 4,000 Class ‘A’ shares and 4,000 Class ‘B’ shares; Tim holds 500 Class ‘A’ shares and 1,000 Class ‘B’ shares; and John holds 500 Class ‘A’ shares. Mary wishes to remove the preferential rights attached to Class ‘A’ shares but Tim opposes.Required:Advise Tim. (10 marks)

题型:单项选择题 A1/A2型题

试述传说时代的文化线索。

题型:单项选择题 A1/A2型题

根据国务院最近发布的规定,各类非农业建设占用耕地的,建设单位必须补充数量、质量相当的耕地,补充耕地的数量、质量实行(),防止占多补少,占优补劣。

A.按面积占一补一

B.按等级折算

C.占少补多

D.按价补偿

更多题库