题目内容
表2-5
测得水样中BaP以高度表示的吸光度为0.862 mAU。在同一水样中加入20μL BaP标准溶液(20mg/L)，加标后测得试样的Height(mAU)=6.584。试计算水样中BaP的含量和实验的加标回收率(水样总体积1mL，不考虑加标体积变化)。
查看答案
搜索结果不匹配？点我反馈
更多问题
Wearing a seat belt in a vehicle （).
The woman uses her personal experiences with the drug Ecstasy to warn others of its dangerous effects. She grew up in a small town in Pennsylvania but moved to New York City to a______ acting school, and it was here that she first came into c______ with drugs. Many of her school friends were drug users and, in an effort to f______ in, she began to use them too. Her story is t______ of many drug addicts. She went from someone who used drugs for fun to someone who couldn't live without them. Finally she had some kind of a b______. Luckily for her, her mother drove to New York to r______ her and she ended up back in Pennsylvania in hospital. She was s______ with horror when she saw her brain scan which showed that Ecstasy had had p______ effects on her brain.
The example of Proctor and Gamble's famous Ivory Soap shows the potential that lies in mass marketing and planned, a______ and the importance of recognizable b______ names. Ivory Soap, first produced in 1879, was well p______ with clever slogans. These slogans, particularly the idea that the soap is so pure that it floats, p______ so successful that they are still p______ today. At the same time, the use of the radio serial for Ivory promotion gave rise to the e______ "soap opera", which has become a modern g______ phenomenon. The development of Proctor and Gamble itself, from a small-scale operation founded by two i______ to a multinational empire of today serves as a good example to build brand names.
同一长度的压杆，截面积及材料均相同，仅两端支承条件不同，则（）杆的临界力最小。
微信支付 
支付宝支付