风机叶轮叶片的形式有三种,高炉鼓风机的叶片属()型。A、前曲型 B、径向型 C、后曲

题型:单项选择题

问题:

风机叶轮叶片的形式有三种,高炉鼓风机的叶片属()型。

A、前曲型

B、径向型

C、后曲型

考点:风机工初级风机工初级风机工题库
题型:单项选择题

设函数f(x)=|x+1|+|xa|(a>0).若不等式f(x)≥5的解集为(-∞,-2]∪(3,+∞),则a的值为________.

题型:单项选择题

“自由不在于幻想中摆脱自然规律而独立,而在于认识这些规律,从而能够有计划地使自然规律为定的目的服务”。过说明自由是

A.对必然的认识

B.摆脱盲目必然的束缚

C.利用规律对世界的改造

D.借助于对事物的认识来作出决定的能力

题型:单项选择题

An anxious mother watched as rescuers freed her baby from a muddy well. After being pulled from the well,the baby joyfully ran to its mom as the rescuers took a break.

It was a difficult and potentially dangerous rescue: the baby was an 8-month-old elephant, and at first its mother thought the humans were trying to harm it. The baby elephant fell into the five-foot-deep well near Kenya's Amboseli National Park. Local people had dug the well for water.

It took 30 minutes to remove the trapped elephant. While Vicki Fishlock of the Amboseli Trust for Elephants made a loud shout to frighten the mother away, two men struggled to get a rope around the baby elephant. Once the rope was in place, Fishlock used her jeep to pull the baby out.

Fishlock recognized Zombe, the mother of the trapped baby elephant,from a mark on her ear. She believes that in the end Zombe realized the humans were trying to help.

“Rescues where the elephant’s family members are around are always stressful, and I'm always happy when everyone is safe,” Fishlock said.“The reunions (团聚) always bring tears to my eyes. The depth of their love for each other is one of the things that make elephants so unusual.”

The very next day, another baby elephant fell into the same well. The 3-month-old's family had been driven away from the area by local people. Once it had been rescued, the Amboseli Trust had to send it to an elephant orphanage (孤儿院) in Nairobi, Kenya's capital city.

The rescues showed the plight of elephants across Africa. Elephants are fighting to survive, as conflicts between the animals and humans are increasing. Thousands of elephants are also being killed for their tusks. The tusks are sold in Asia, where ivory trinkets are in high demand.

The Amboseli Trust has been studying elephants and trying to help them since 1972. Fishlock said, “We hope this rescue persuades people that elephants are special and deserve to be protected and treasured.”

小题1:We can learn from the text that _____.

A.Fishlock had seen the baby elephant before

B.The mother elephant was a great help to rescuers

C.the well was dug by local people to trap elephants

D.the mother elephant was unfriendly at first to the rescuers小题2:What causes Fishlock to think that elephants are special?

A.Their trust in humans.

B.The deep love between them.

C.Their great ability to survive.

D.The good communication between them.小题3:What did the two baby elephants have in common?

A.They were both 8 months old.

B.They were both rescued by local people.

C.They were both trapped in the same well.

D.They were both reunited with their mothers.小题4:The underlined word "plight" in Paragraph 7 probably means“______”.

A.a strong personality

B.A dangerous situation

C.an annoying habit

D.a close relationship小题5:What would be the best title for the text?

A.An elephant rescue

B.The elephant, an unusual animal

C.An elephant rescue organization

D.Conflicts between humans and elephants

题型:单项选择题

烘炉是把冷炉逐渐加热升温以去除筑炉材料中存在的水分,并使耐火材料内部结构完成某种组织转变。烘得好的炉子,可以使耐火材料的高温强度最大,不易剥落损坏。

题型:单项选择题

( )认为政府部门投资效率偏低是导致政府支出规模不断扩大的原因。

A.皮考克
B.瓦格纳
C.马斯格雷夫
D.鲍莫尔

更多题库