当前位置:

2014年职称英语考试卫生类模拟套题十五

发表时间:2013/6/27 9:46:26 来源:互联网 点击关注微信:关注中大网校微信
关注公众号

第六部分:完型填空 (第51~65题,每题1分,共15分)

阅读下面的短文,文中有15处空白,每处空白给出了4个选项,请根据短文的内容从4个选项中选择1个最佳答案,涂在答题卡相应的位置上。

Better Solar Energy Systems: More Heat, More Light

Solar photovoltaic thermal energy systems, or PVTs, generate both heat and electricity, but 51 now they haven’t been very good at the heat-generating part compared to a stand-alone solar thermal collector. That’s because they operate at low temperatures to cool crystalline silicon solar cells, which lets the silicon generate more 52 but isn’t a very efficient way to gather heat.

That’s a problem of 53_. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower 54 . And it’s also a space problem:photovoltaic cells can take up all the space on the roof, leaving little room for thermal applications.

In a pair of studies, Joshua Pearce, an associate professor of materials science and engineering, has devised a 55 in the form of a better PVT made with a different kind of silicon. His research collaborators are Kunal Girotra from ThinSilicon in California and Michael Pathak and Stephen Harrison from Queen’s University, Canada.

Most solar panels are made with crystalline silicon, but you can also make solar cells out of amorphous silicon, 56 known as thin-film silicon. They don't create as much electricity, but they are lighter, flexible, and cheaper. And, because they 57 much less silicon, they have a greener footprint. Unfortunately, thin-film silicon solar cells are 58 to some bad-news physics in the form of the Staebler-Wronski effect.

“That means that their efficiency 59 when you expose them to light-pretty much the worst possible effect for a solar cell,” Pearce explains, which is one of the 60 thin-film solar panels make up only a small fraction of the market.

However, Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new 61 of PVT. You don’t have to cool down thin-film silicon to make it work. In fact, Pearce’s group discovered that by heating it to solar-thermal operating temperatures, near the boiling 62 of water, they could make thicker cells that largely 63 the Staebler-Wronski effect. When they applied the thin-film silicon directly to a solar thermal energy 64 , they also found that by baking the cell once a day, they 65 the solar cell's electrical efficiency by over 10 percent.

51. A unless B when C if D until

52. A electricity B magnetism C ultraviolet D radioactivity

53. A dynamics B geology C economics D biology

54. A reward B cost C bill D pay

55. A decision B solution C suggestion D qualification 10

56. A roughly B probably C commonly D specially

57. A retrieve B merge C exchange D require

58. A vulnerable B necessary C important D renewable

59 . A works B counts C rises D drops

60. A restrictions B advances C reasons D strengths

61. A size B shape C type D brand

62. A area B point C place D extent

63. A overcame B promoted C improved D postponed

64. A transformer B adaptor C transmitter D collector

65. A boosted B defined C wasted D lower

编辑推荐:

2014年职称英语考试模拟题汇总

2013年职称英语考试真题汇总

2013年职称英语考试成绩查询时间

2014年职称英语考试网络培训

(责任编辑:vstara)

9页,当前第8页  第一页  前一页  下一页
最近更新 考试动态 更多>