搜题请搜索小程序“爱下问搜题”
问题 问答题 简答题

在碱性操作条件下吹炼终了钢液中为什么会有“余锰”？余锰高低受哪些因素影响？

答案

参考答案：

与硅相似，锰也很容易被氧化，反应式为：

[Mn]+（1/2）{O2}＝（MnO）放热

[Mn]+（FeO）＝（MnO）+[Fe]放热

[Mn]+[O]＝（MnO）放热

锰的氧化产物是碱性氧化物，在冶炼前期所形成的（MnO·SiO2），随着渣中CaO含量的增加，会发生

（MnO·SiO2）+2（CaO）＝（2CaO·SiO2）+（MnO）反应，（MnO）呈自由状态，吹炼后期炉温升高后，（MnO）被还原，即：（MnO）+[C]＝[Mn]+{CO}或（MnO）+[Fe]＝（FeO）+[Mn]。吹炼终了钢中锰含量也称为余锰或残锰。

判断题

合同约定由债务人甲向第三人乙履行交货义务，甲在所交货物的质量不符合合同约定时，应当向乙承担违约责任。( )
查看答案
阅读理解

National parks in the UK are a wonder to see, run by the National Trust, a non-profit charity which maintains Great Britain's historical and natural landscapes. Britain's park Authority has made planning restrictions to protect these wilderness areas in housing and commercial activities.

Mainland England and Wales have the largest number of protected parks. The first established area was the l,438 kilometer Peak District. The first national park lies in northern and central England. The Peak District with vast beauty is thought to be the world's most visited national park after Japan's Mount Fuji.

In the northwest area of Wales lies Snowdonia National Park. This attractive, mysterious ancient landscape is home to steep mountains. Walking trails to Mount Snowdon is only one of several exciting activities for hikers.

National parks in the UK can also boast of having Britain's largest protected wetland "The Broad", just outside the village of Homing. An ideal spot for families, this 200-mile area combines waterways with an interesting intersection(交叉) of windmills, castles and an ancient Normal church.

Spreading across 885 miles of truly impressive rocky land is Lake District National Park. England's largest park attraction is spread between Edinburgh to the north and Manchester to the south. Although the land itself seems wild, almost 40,000 people live within the park. Within this district's vast borders we can find over 6,000 archaeological(考古的) sites and monuments dating back to prehistory.

The United Kingdom has taken great care to preserve its wilderness areas for the future generations, and all the parks are adventures waiting to De found which can be enjoyed by both natives and visitors.

小题1:Who is in charge of the National parks in the UK? (no more than 3 words)

小题2:According to the passage, which is thought to be the world's most visited national park? (no more than 5 words)

小题3:If you want to see ancient monuments, where would you go? (no more than 4 words)

小题4:For whom are the wild areas preserved in the UK? (no more than 4 words)

小题5:What's the text mainly about? (no more than 6 words)
查看答案