1、3. When large decrease in turbine load the steam from the steam generators is sent to the_. steam condenser atmosphere steam dump system heat exchanger4. An excess of coolant inventory can result in a_. power increase temperature increase reactor trip turbine trip5. Following the coastdown of the co
2、olant pumps, the core residual heat will be removed by_. condensers natural circulation boiling heat transfer emergency power6. The operation of a nuclear plant is _than operating a modern fossil fuel power station. easier more difficult rather more complex7. The heat is transferred by the reactor c
3、oolant from the core to the_. cecondary loop outlet nozzles steam generators pressurizer8. The fuel rod provides_to the escape of fission products. two barriers three barriers seals a barrier9.The CEA guide tubes are made of_. stainless steel ceramic zircaloy B4C10. The helium inside the fuel claddi
4、ng improves the _. characteristic gap heat conductivity gap heat convection clad strain11. The CEA guide tubes are arranged_. in the fuel assembly around the fuel assembly in the center of fuel assembly outside the fuel assembly12. The coolant can _through the guide tubes. not flow be flow pass13. T
5、here _ steam generator（s） in each primary loop. is one are two are there is no14. At the top of the tube bundle shroud, _ are mounted. eggcrates steam-water separators plates baffles15. There _ in the system 80+ steam generator. is one feedwater inlet are two feedwater inlets are three feedwater inl
6、ets are many feedwater inlets16. The flywheel on the motor is to provide_. energy water coastdown flow torque17. The temperature of the water in the seal assembly is maintained within acceptable limits by_. oil steam water and oil18. In accordance with the coolant temperature program,the average rea
7、ctor coolant temperature is _ when steam demand is increased. constant fall raised high19. In pressurized water reactors water is used as_. moderator coolant both a and b neither a nor b20. The thermal efficiency of PWRs is_. more than 40% about 30% less than 10% about 70%21. The space between the r
8、eactor vessel and the core barrel is the _. fuel rods control rods downcomer plenum22. The ECCS is provided to_. cool the core control reactivity control volume drive pump23. There are_ successive barriers in PWR to prevent radioactivity escape. two three four five24. The containment enclose the_. r
9、eactor reactor and pressurizer primary system and secondary system entire primary system25. From the text the safest nuclear power plant may be a _. expensive one cheap one big one small one26. Following a decrease in turbine load, the water pressure and temperature in the reactor_. will increase in
10、crease decrease will be unchanged27. A temperature decrease of reactor vessel water results in an_. insertion of control rods power decease increase of reactivity28. Loss of power is a _. upset condition abnormal increase reactor shutdown accident29. Inadvertent auxiliary spray will result in_. temp
11、erature decrease power decrease pressure decrease abnormal condition30. The long-term control of core reactivity means adjustment of_. boric acid power output coolant 31. The burnable absorber rod assembly provides the capability of high absorber strength_. in all its life at the beginning of refuel
12、ing at the end of refueling cycle during operation32. The fuel assemblies used in a reactor are_. similar different three types same33. In the fuel rod the spring is set on the_. pellet column spacer disc end cap top34. The CEA guide tubes are welded to the_. spacer grids lower end fittings35. The f
13、uel spacer grids are made of_. stiff arches springs zircaloy strips36. After long time radiation the boron carbide will_. decrease in mass be swelling increase in mass be dissipated37. The economizer increases the cold leg side _ before coolant leaving the steam generator. flow rate temperature temp
14、erature difference relative flow38. The water from the steam separators flows down into the _. economizer shroud bundle evaporator section39. In the downcomer the water is_. saturated boiling very cold subcooled40. The pump is connected with the motor by a_. diaphragm tube coupling casing41. _ press
15、urizer heaters are connected to proportional controllers. A few The remaining Most of the Many42. The fluid from economizer section is _. two-phase flow boiling water subcooled water saturated water43. The amount of heat that has been converted in steam turbine is _ that removed in condenser. more t
16、han less than same as similar to44. The hot primary fluid exchanges its heat with the secondary fluid in the_. condenser header45. Residual heat-removal system remove the decay heat from the core_. during plant operation after plant shutdown during start-up during transient condition46. The _ is con
17、nected to the spent fuel pond by transfer canal. containment pressure vessel pipe reactor cavity47. One of the important factors influencing containment design is _. the size the pressure inside LOCA economic48. A sodium hydroxide additive is provided to reduce_. the iodine concentration the pressure the radioactivity vapor四、解释如下蒸发流程图，阐述作用和工作原理。五、解释如下除气装置流程图，阐述作用和工作原理。六、客观的描述你所知道的日本福岛核电站核泄漏事故的过程，结合课本知识，分析其原因，并且指明有哪些人为的失误，并设想更好的控制策略。
