问题 问答题 简答题

试述密炼混炼的原则和操作方法。

答案

参考答案:

㈠原则:容量须严格控制,硫黄不能在密炼机中加入。配合剂是分次加入,每次加完后上顶栓必须完全下降,并加压混炼,但当粉料过多时,压力不宜增加过快。

㈡顺式加药法操作:

⑴先加塑胶、再生胶或母胶及固体软化剂混炼一定时间;

⑵加入硬脂酸、防老剂、氧化锌、促进剂,有时固体软化剂也一起加入混炼一定的时间;

⑶加入炭黑,多者可分2-3次加入;

⑷加入填充料;

⑸加入液体软化剂。

阅读理解

阅读理解

      Can dogs and cats live in perfect harmony in the same home?People who are thinking about adopting a dog as a friend for their cats are worried that they will fight.A recent research has found a new recipe of

success.According to the study,if the cat is adopted before the dog,and if they are introduced when still

young (less than 6 months for cats,a year for dogs),it is highly probable that the two pets will get along

swimmingly.Twothirds of the homes interviewed reported a positive relationship between their cat and dog.

      However,it wasn't all sweetness and light.There was a reported coldness between the cat and dog in

25% of the homes,while aggression and fighting were observed in 10% of the homes.One reason for this is probably that some of their body signals are just opposite.For example,when a cat turns its head away it

signals aggression,while a dog doing the same signals submission.

     In homes with cats and dogs living peacefully,researchers observed a surprising behaviour.They are

learning how to talk each other's language.It is a surprise that cats can learn how to talk'Dog',and dogs can learn how to talk'Cat'.

     What's interesting is that both cats and dogs have appeared to develop their intelligence.They can learn to read each other's body signals,suggesting that the two may have more in common than was previously

suspected.Once familiar with each other's presence and body language,cats and dogs can play together,

greet each other nose to nose,and enjoy sleeping together on the sofa.They can easily share the same

water bowl and in some cases groom (梳理)each other.

     The significance of this research on cats and dogs may go beyond pets-to people who don't get along,

including neighbors,colleagues at work,and even world superpowers.If cats and dogs can learn to get

along,surely people have a good chance.

1.The underlined word "swimmingly" in Paragraph 1 is closest in meaning to ________.

A.early  

B.sweetly

C.quickly  

D.smoothly

2.Some cats and dogs may fight when ________.

A.they are cold to each other

B.they look away from each other

C.they misunderstand each other's signals

D.they are introduced at an early age

3.What is found surprising about cats and dogs?

A.They eat and sleep together.

B.They observe each other's behaviours.

C.They learn to speak each other's language.

D.They know something from each other's voices.

4.It is suggested in Paragraph 4 that cats and dogs ________.

A.have common interests

B.are less different than was thought

C.have a common body language

D.are less intelligent than was expected

5.What can we human beings learn from cats and dogs?

A.We should learn to live in harmony.

B.We should know more about animals.

C.We should live in peace with animals.

D.We should learn more body languages.

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