以下哪项属于道岔转辙器部分?()
A.辙叉心
B.尖轨
C.护轨
D.直轨
A.辙叉心
B.尖轨
C.护轨
D.直轨
第2题
提速道岔上长度(不含钉帽的全长)为147mm的销钉()。
A.用于钢枕滑床板
B.用于转辙器滑床板
C.用于护轨垫板
D.可以通用
第6题
When we think about the future of the universe, we can see our "track" many billions of years into the future, but after that there are decision points to be dealt with and possible fates to consider. The goal of science is to reduce the ambiguity at the decision points and find the true road that will be followed.
According to the passage, it is difficult to be certain about the distant future of the universe because we______.
A.have too many conflicting theories
B.do not have enough funding to continue our research
C.are not sure how the universe is put together
D.have focused our investigations on the moon and planets
第9题
高锰钢整铸辙叉叉趾、叉跟轨头及下颚部位裂纹超过()时,应及时更换。
A.10mm
B.20mm
C.25mm
D.30mm
第10题
A.开挖深度超过3m(含3m)或虽未超过3m但地质条件和周边环境复杂的基坑支护、降水过程
B.搭设高度18m及以上的落地式钢管脚手架工程
C.建筑幕墙安装工程
D.搭设高度4m及以上的混凝土模板支撑工程