如何保证检测结果的质量？
参考答案：
（1）内部质量控制：有证标准物质（参考标准）和/次级标准物质（参考物质）的使用，平行样测定，空白试验，加标回收，质量控制图等。
（2）外部质量控制：参加实验间比对计划和实验间能力验证计划。
（3）利用相同或不同方法进行重复检测。即开展人员之间比对、方法之间比对、仪器之间比对。
（4）对存留样品进行再检测。
（5）分析一个样品不同特性结果的相关性。
| 完形填空。 | ||||
| One day I came home from school, changed my clothes and got ready for work. I work at a local restaurant in town as a cashier, seater and waiter. I went to work feeling 1 . And to make matters worse, I was busy that evening. It's the same thing over and over again. 2 with customers who complain about their food and where they are 3 is too big or too small. Little things like that tend to 4 a lot of us 5 but we manage to deal with it. Three elderly ladies walked in and sat by the windows. It happened to be the very 6 near where I keep the dirty 7 in the boxes. Trying to keep up with all the dirty tables, customers leaving and coming in and 8 running all over the house, it was crazy. 9 these elderly women were watching 10 I was working to make sure every table was clean and ready for the next customers. When they 11 their meals, I took their plates back to the kitchen. They talked to me for a while about school, how I was doing, what 12 I was in and what I planned to do in the future. 13 they were leaving, they walked past me and one of them said to me in a 14 and gentle voice, "You are going places. And that was it." They left the 15 and I had tears in my eyes, because they gave me 16 to believe in myself. They 17 my spirit from being down and gave me a 18 to keep on working hard. People used to tell me that I couldn't have a career in 19 until I had a degree. I'm now a co-anchor (联合主持人)of a student-produced television 20 . And the best thing is: I'm only 17 years old and I am a senior in high school. | ||||
|