全部题库 / 理工类 / 试题详情

单选题理工类

2016-03-28

The Thames Tunnel project was moredifficult than any previous projects undertaken in Britain.

A．Right

B．Wrong

C．Not mentioned

查看答案及解析进入在线模考

参考答案

C

答案解析

暂无解析

你可能感兴趣的试题

1 回答题：

Geothermal（地热）Energy

1 Since heat naturally moves from hotter regions tocooler ones， the heat from the earth's center flows outwards towardsthe surface。 In this way， it transfers to the next layer of rock。 If the temperatureis high enough， some of this rock melts and forms magma（岩浆）。 The magmaascends in its turn towards the earth's surface。 It often remains well below the earth's surface， creating vast areasof hot rock。 In such regions， there are deep cracks， which allow rainwater to descend underground。 Some of the heatedrainwater travels back up to the earth's surface where it will appear as a hotspring。 However， if this ascendinghot water reaches a layer of impermeable（不可渗透的）rock， it remains trapped， forming a geothermal reservoir。 If geothermalreservoirs are close enough to the surface， they can be reached by drilling wells。 Hot water and steamshoot up the wells naturally， and can be used to produce electricity in geothermalpower plants。
2。A few geothermal power plants depend on dry-stemreservoirs which produce steam but little or no water。 In these cases， the steam is pipedup directly to provide the power to spin a turbine generator。 The first geothermalpower plant， constructed at Lardarello in Italy， was of this type， and is stillproducing electricity today。
3。Most currently operating geothermal power plants areeither "flash" steam plants or binary（双重的）plants。 Flash plants produce mainly hot water ranging intemperature from 300° to 700°Fahrenheit。 This water is passed through one or two separators wherereleased from the pressure of the underground reservoir， it"flashes" or boils into steam Again， the force of this steam provides the energy to spin theturbine and produce electricity。 The geothermal water and steam are then reinjecteddirectly back down into the earth to maintain the volume and pressure of thereservoir。 Gradually they will be reheated and can then be usedagain。
4。A reservoir with temperatures below 300° Fahrenheit is nothot enough to flash steam but it can still be used to generate electricity inbinary fluid。 The steam from this is used to power the turbines。 As in the flashsteam plant， the geothermal water is recycled back into the reservoir。
Paragraph 1_________

A．Recyclable water and steam

B．Binary plants

C．Flash steam plants

D．Generation of electricity

E．Origin of geothermal energy

F．Dry steam plants

查看解析在线模考

2 Paragraph 2_________

A．Recyclable water and steam

B．Binary plants

C．Flash steam plants

D．Generation of electricity

E．Origin of geothermal energy

F．Dry steam plants

查看解析在线模考

3 Paragraph 3_________

A．Recyclable water and steam

B．Binary plants

C．Flash steam plants

D．Generation of electricity

E．Origin of geothermal energy

F．Dry steam plants

查看解析在线模考