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混炼胶后胶料的补充加工与处理。

答案

参考答案：

1．压片与冷却

压片后立即浸涂隔离剂液进行冷却与隔离，并经进一步吹风干燥，使胶片温度降低到50℃以下。

2．滤胶

对于质量和性能要求比较严格的某些胶料，特别是气密性要求严格的内胎胶料、气囊胶和其他气动薄膜制品的胶料，混炼后必须滤胶。

3．停放与管理

一般需要停放4~8小时以上才能使用。停放的目的是：a．使胶料进行松弛，减小收缩；b．使配合剂继续扩散，促使胶料进一步均匀；c．使橡胶与炭黑进一步相互作用，生成更多的结合橡胶。在储存期间注意胶料的通风和散热，以防焦烧。

单项选择题

The idea of test-tube babies may make you either delighted at the wonders of modern medicine or irritated while considering the moral, or legal, or technological implications of starting life in a laboratory. But if you’’ve ever been pregnant yourself, one thing is certain: You wonder what it’’s like to carry a test-tube baby. Are these pregnancies normal Are the babies normal The earliest answers come from Australia, where a group of medical experts at the Queen Victoria Medical Center in Melbourne have taken a look at the continent’’s first nine successful invitro pregnancies. The Australians report that the pregnancies themselves seemed to have proceeded according to plan, but at birth some unusual trends did show up. Seven of the nine babies turned out to be girls. Six of the nine were delivered by Caesarean section. And one baby, a twin, was born with a serious heart defect and a few days later developed life-threatening problems.What does it all mean Even the doctors don’’t know for sure, because the numbers are so small. The proportion of girls to boys is high, but until there are many more test-tube babies no one will know whether that’’s something that just happened to be like that or something special that happens when egg meets sperm in a test tube instead of a fallopian tube. The same thing is true of the single heart defect. It usually shows up in only 15 out of 60,000 births in that part of Australia, but the fact that it occurred in one out of nine test-tube babies does not necessarily mean that they are at special risk. One thing the doctors can explain is the high number of Caesareans. Most of the mothers were older, had long histories of fertility problems and in some cases had had surgery on the fallopian tubes, all of which made them likely candidates for Caesareans anyway.The Australian researchers report that they are quite encouraged. All the babies are now making normal progress, even the twin with the birth defects.

What is the author’s tone in this passage

A．Depressed.

B．Optimistic.

C．Opposing.

D．Negative.
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判断题

可弯曲刮板输送机随工作面的推进可实现蛇形自移。（）
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