首页
登录
职称英语
Researchers at MIT are developing new technology for converting heat into li
Researchers at MIT are developing new technology for converting heat into li
游客
2023-12-22
58
管理
问题
Researchers at MIT are developing new technology for converting heat into light and then into electricity that could eventually save fuel in vehicles by replacing less-efficient alternators and allowing electrical systems to run without the engine idling. The technology, called thermophotovoltaics, uses gasoline to heat a light-emitting material, in this case tungsten. A photovoltaic cell then converts the light into electricity. The idea has been around since the 1960s, says John Kassakian, MIT electrical engineering and computer science professor. But until now, the light emitters for the photovoltaics produced inefficient and very costly systems. Improvements in the materials used in these latest devices—possible in part because researchers can modify the material structure at the nano-scale—are now making much more efficient systems, Kassakian says.
According to Kassakian, the system could potentially be a more efficient way to power electrical systems in a vehicle than the current alternator-based one, which wastes energy in two stages: the internal combustion engine converts only about 30 percent of the energy in fuel into movement, and then the alternator is only 50 percent efficient in converting the mechanical energy into electricity. He says a small prototype thermophotovoltaics device that could confirm the system’s improved efficiency might be ready in a year.
The researchers modified the surface structure of the light emitter, etching into it nano-sized pits to tune the wavelengths of light emitted to precisely those a photovoltaic cell can convert most efficiently into electricity. They further refined the device with the use of filters that allow the desired wavelengths of light to pass through to the photovoltaic cells, but reflect other wavelengths back to the light emitter. The reflected light carries energy that helps keep the emitter hot, reducing the amount of fuel needed.
In addition to replacing the alternator with a thermophotovoltaic module, says Kassakian, the technology could be part of an air-conditioning system for vehicles that doesn’t require a compressor. Because this would significantly decrease the load on an engine, it could make it possible to turn off the engine when the vehicle stops in traffic and easily restart it. Today’s hybrids use this technique to save gas, but require large batteries to provide electricity for the radio and lights, and to restart the engine, and they have to turn the engine back on when the battery charge runs out. In the new MIT system, these batteries wouldn’t be necessary. [br] Which of the following expressions is closest in meaning to "idling" in paragraph 1?
选项
A、Being empty.
B、Lacking substance.
C、Being not in use or operation.
D、Being down.
答案
C
解析
转载请注明原文地址:https://www.tihaiku.com/zcyy/3295925.html
相关试题推荐
ResearchersatMITaredevelopingnewtechnologyforconvertingheatintoli
ResearchersatMITaredevelopingnewtechnologyforconvertingheatintoli
ResearchersatMITaredevelopingnewtechnologyforconvertingheatintoli
[originaltext]PassageOne:Chinaisadevelopingcountrywhichisnowconfr
Bluetoothisthenewestkidonthetechnologyblock,anditholdsalotofp
I’dliketodiscusssomeofthewaysresearcherstrytomeasurequalityofli
I’dliketodiscusssomeofthewaysresearcherstrytomeasurequalityofli
I’dliketodiscusssomeofthewaysresearcherstrytomeasurequalityofli
I’dliketodiscusssomeofthewaysresearcherstrytomeasurequalityofli
I’dliketodiscusssomeofthewaysresearcherstrytomeasurequalityofli
随机试题
______isnotamodernistnovelistofBritain.A、JamesJoyceB、VirginiaWoolfC、D
ToHelptheKids,ParentsGoBacktoSchool[A]Forafewyearsn
Therewassomuchnoisethatthespeakercouldn’tmakehimself______.A、hearingB
卓越的remarkable;prominent
试验检测报告标题区由表格名称、唯一性标识编码、试验室名称、报告编号、页码等内容组
A.未曾在中国境内上市销售的药品B.未曾在中国生产的药品C.必须凭执业医师或执业
关于住房公积金的转移、中断和恢复,下列说法不正确的有()。A.职工变动工
属于青蒿鳖甲汤特征的是A.皮肤蒸热 B.壮热烦渴 C.高热惊厥 D.夜热早
下列属于直接灸的为A.无瘢痕灸 B.温和灸 C.温针灸 D.雷火神针
下列关于锅炉缺水事故的叙述中,不正确的是()。A.锅炉严重缺水会使锅炉蒸发受
最新回复
(
0
)