生物分离工程可分为几大部分，分别包括哪些单元操作？
参考答案：
生物分离过程一般分四步：
1.固-液分离（不溶物的去除）：离心、过滤、细胞破碎目的是提高产物浓度和质量
2.浓缩（杂质粗分）：离子交换吸附、萃取、溶剂萃取、反胶团萃取、超临界流体萃取、双水相萃取以上分离过程不具备特异性，只是进行初分，可提高产物浓度和质量。
3.纯化：色谱、电泳、沉淀，以上技术具有产物的高选择性和杂质的去除性。
4.精制：结晶、干燥
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| When people find something valuable and return it to its owner, they are often given a reward. This is because the person not only found what was lost but also spent time 1 its owner or taking it to the police station. There was once a young boy 2 found a woman's purse in a shopping centre. Inside the purse there 3 some money and the woman's driving license. Her name and 4 were printed on the license, so the boy knew where she lived. That evening he went to her house and 5 her door. When she opened it, he said, "I found your purse," and handed it to her. "Thank you very much," she said. She opened her purse and took out all the money. She wanted to give the boy a small reward, 6 there were only bills of ＄20 in the purse and she thought that $ 20 was too 7 to give the boy." I'm sorry," she said, "but I don't have any small 8 to give you." The boy said, "That's all right," and he went away. A few days later he found 9 woman's purse. It also had her driving license in it, so he knew where she lived. He went to her house and said "I found your purse," and handed it to. "Thank you very much," she said. She opened her purse and took out all her money. "That's 10 ", she said, "Before I lost my purse I had a $100 bill and a $20 bill in it. Now I have a $100 bill, a $10 bill and two $5 bills." "Yes," the boy said, and smiled. | |||
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