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问题 问答题 简答题

有机合成离子交换树脂是怎样命名的？

答案

参考答案：

第1位数字～活性基团代号；

第2位数字～骨架代号；

第3位数字～顺序代号；

联接符号后的数字～交联度（％）

注：大孔型树脂型号前加“D”，凝胶型树脂型号前不加任何字母。

单项选择题

Why is（）fun What delights may its practitioner expect as his reward First is the sheer joy of making things. As the child delights in his mud pie, so the adult enjoys building things, especially things of his own design. Second is the pleasure of making things that are useful to other people. Third is the fascination of fashioning complex puzzle-like objects of interlocking moving parts and watching them work in subtle cycles, playing out the consequences of principles built in from the beginning. Fourth is the joy of always learning, which springs from the（）nature of the task. In one way or another the problem is ever new, and its solver learns something: sometimes （）, sometimes theoretical, and sometimes both. Finally, there is the delight of working in such a tractable medium. The（）, like the poet, works only slightly removed from pure thought-stuff. Few media of creation are so flexible, so easy to polish and rework, so readily capable of realizing grand conceptual structures. Yet the program（）, unlike the poet’s words, is real in the sense that it moves and works, producing visible outputs separate from the construct itself. It prints results, draws pictures, produces sounds, moves arms. Programming then is fun because it gratifies creative longings built deep within us and delights sensibilities we have in common with all men.

sometimes （）, sometimes theoretical, and sometimes both.

A．semantic

B．practical

C． lexical

D．syntactical
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单项选择题

在编制标底价格的时候，确定利润这一费用的基础是( )。

A．行业平均水平

B．询价

C．市场价

D．确定的工程利润百分比基数
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