首页
登录
职称英语
The oceans, which cover nearly three-quarters of Earth’s surface, remain lar
The oceans, which cover nearly three-quarters of Earth’s surface, remain lar
游客
2024-02-27
6
管理
问题
The oceans, which cover nearly three-quarters of Earth’s surface, remain largely unexplored because of their vastness and inaccessibility to us air breathers. Webb Research of East Falmouth, Massachusetts, hopes to open up much of that mystery field with a new underwater vehicle that is pushed ahead solely by the ocean itself, so it can potentially study the watery depths for years at a time. Such long-lasting detectors may someday form fleets that provide up-to-minute data for weather forecasting.
In the past, such autonomous underwater vehicles, or AUVs, have been battery powered and therefore required frequent recharges that limited their distance and depth of travel. Webb’s Slocum glider(滑翔机) hopes to solve this problem. "We conceived of a thermally powered engine to get the energy from the colder deep water of the ocean and the shallower warm water," Clayton Jones, an engineer at Webb Research, explains. "We picked out a material that undergoes a state change between those two temperatures in the ocean." When cold, this form-shifting substance is a compact solid. When warm, it expands and becomes a less dense liquid. The material’s expansion in warmer waters charges an internal mechanism that acts like stored power to control its buoyancy: by pumping mineral oil in and out of an external air bag, it alters its volume but maintains its weight. "The glider takes up more volume and becomes lighter than the water around it--less dense," Jones says.
Scientists can also fit the Slocum glider with a variety of different sensory equipment and Global Positioning Systems. Each time it surfaces, it can raise its tail antenna(天线) to transmit data to and receive instructions from researchers sitting comfortably in their cozy offices. The glider will have its first test in salt water at the end of this September.
The gliders could also get through and follow previously unstudied phenomena such as small underwater eddies (漩涡), which are vital to understanding water transport and heat flow in the ocean and therefore play an important role in storm formation and other weather development. "We have all these data snapshots(快照) from floats that just flow with the deep ocean current," Jones says. "To be able to fly through eddy sections, then transport with the whole eddy itself as it moves through the ocean, would be a very nice phenomenon to take a look at." [br] The power of the new AUV is stored in the ______.
选项
A、form-shifting substance
B、internal mechanism
C、spring that is pushed into a tight coil
D、external bladder
答案
B
解析
由题干定位到原文第二段第三句“We conceived of a thermally powered engine…and the shallower warm water.”。
转载请注明原文地址:https://tihaiku.com/zcyy/3485974.html
相关试题推荐
Inourcollege,scholarshipstudents______(占了学生总数的近三分之一).accountfornearlya
Londonhasbeena【B1】______cityfornearly1,000years,andmanyofits【B2】
Londonhasbeena【B1】______cityfornearly1,000years,andmanyofits【B2】
Londonhasbeena【B1】______cityfornearly1,000years,andmanyofits【B2】
Londonhasbeena【B1】______cityfornearly1,000years,andmanyofits【B2】
ManyaresurprisedtolearnthatAntarctica(南极)isnearlytwicethesizeof
ManyaresurprisedtolearnthatAntarctica(南极)isnearlytwicethesizeof
ManyaresurprisedtolearnthatAntarctica(南极)isnearlytwicethesizeof
ManyaresurprisedtolearnthatAntarctica(南极)isnearlytwicethesizeof
ManyaresurprisedtolearnthatAntarctica(南极)isnearlytwicethesizeof
随机试题
Bush’sMBATwenty-sixof42presidents,includingBillClinton,werelawyers.
______,allmachinesarecombinationsofsimplerpartssuchasthelever,thepu
Inwhichcountryhaveseveralpeoplediedbecauseoftheflood?[br][originalt
下表中两个事务的调度带来的问题是() A.丢失修改 B.读脏数据 C.没
将人体实验分为临床性与非临床性研究并提出不同道德原则的医德文献是A.“东京宣言”
在娱乐方式多元化的今天,“________”是不少人特别是中青年群体对待戏曲的态
能补脾肺之气,并能固涩肾精的药物是()A.白术 B.山药
A.炒黄品 B.炒焦品 C.炒炭品 D.麸炒品 E.生品医师处方写地榆时
①艺术接触者掌握艺术语言的内涵,并不容易。主体的感觉与判断虽是由客体的特定形态所
某市一房地产开发商兴建一栋26层的商住楼,于2016年12月招标后,由某建筑工程
最新回复
(
0
)