问题 问答题

固溶体合金的相图如图7-1所示,试根据相图确定:

①成分为ω(B)=40%的合金首先凝固出来的固体成分;

②若首先凝固出来的固体成分含ω(B)=60%,合金的成分为多少

③成分为ω(B)=70%的合金最后凝固的液体成分;

④合金成分为ω(B)=50%,凝固到某温度时液相含有ω(B)=40%,固体含有ω(B)=80%,此时液体和固体各占多少

答案

参考答案:

①在合金成分线与液相线相交点作水平线,此线与固相线交点的合金成分即为首先凝固出来的固体成分:ω(B)=85%。

②作ω(B)=60%垂直线与α固相线相交点的水平线,此线与液相线L相交点的成分即为合金成分:ω(B)=15%。

③原理同上:合金成分ω(B)=20%。

④利用杠杆定律:

[*]

固体所占的比例=1-75%=25%

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Every human being is fallible; we make mistakes. In America when a mistake has been made, it is considered fitting for the person (1) to acknowledge his or her error and to apologize to anyone who has been inconvenienced. Even (2) are expected to admit their mistakes and apologize for them. Trying to (3) a mistake and denying your guilt are considered to be indicative of serious (4) .
If you make a mistake that (5) a group of people, a public apology is considered the best method for (6) . If the mistake was a serious one, or if some people were inconvenienced more than others, then the (7) should follow the public apology with private ones to (8) .
It is especially important for executives and company heads to be able to admit their mistakes. Sometimes leaders are afraid that if they (9) , they will lose the respect of their employees. Actually (10) — if you are honest with your employees and yourself, (11) , and show that you are willing to accept blame when you make a mistake, then your employees will be (12) you. They will also be more likely to admit their own mistakes.
If you (13) one person, it is usually best to apologize to that person alone, unless your mistake (14) by a large group of people. For example, if Leonard (15) to Mr. Todd during a committee meeting, it would be (16) for Leonard to apologize to Mr. Todd at the next committee meeting. If the (17) created by the initial mistake is public, then the apology should be public. However, if Leonard raised his voice to Mr. Todd when only the two of them (18) , he may apologize privately. Notice as well (19) the apologies are. As soon as you realize you have made a mistake, you should (20) .