首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
职称考试
Earth’s Inner Core Scientists have long struggled to understand what lies at...
Earth’s Inner Core Scientists have long struggled to understand what lies at...
admin
2020-12-24
7
问题
Earth’s Inner Core
Scientists have long struggled to understand what lies at the planet’s center. Direct observation of its center is impossible, so researchers must _______ (51) to other evidence.
In 1889, a German scientist detected a severe earthquake in Japan. Geophysicists concluded that shock waves_______(52) jolts (晃动)from one side of Earth through the center to the other side. Then in 1936, Danish geophysicist Inge Lehmann studied the waves’________(53) to determine that within Earth’s core of molten (溶化了的)iron lies a solid inner core — but_______(54) that core was made of eluded (难倒)her. Other geophysicists quickly determined that Lehmann’s inner core was composed mostly _____(55) iron. Since then, Lehmann’s discovery has _______ (56) conventional Earth science.
But now scientists are challenging traditional theory with new and radical_______(57).For example, Earth’s center could actually contain an “inner core within the inner core”, claim Ishii and colleague Adam Dziewonski.
Analyzing hundreds of thousands of earthquake wave_______ (58), they maintain that the inner core has at its heart a tiny, even more solid sphere (球体).This sphere “may be the oldest fossil_______(59) from the formation of Earth,” says Dziewonski.
Dziewonski and Ishii speculate that shortly_______ (60) Earth formed around 4. 8 billion years ago, a giant asteroid (小行星)smashed into the young planet and nearly melted it. But Earth’s center didn’t quite melt; it_______(61) mass as the planet cooled.The core within a core may be the kernel (核心)that endured. “ Its presence could change our basic ideas about the ______ (62) of the planet/' Dziewonski says.
Dziewonski’s idea is tame (温和的)compared to the _______ (63) theories of independent geophysicist J. Marvin Herndon. Earth’s inner core is made not of iron, he claims, but a_______(64) of nickel and silicon. Herndon has a truly revolutionary notion:
Within the nickel silicide (桂化物)inner core is also an “inner” inner core — an 8 km-wide ball of the element uranium. Uranium is radioactive. Herndon thinks the uranium releases heat energy as its atoms_______(65) fission-split and crash into one another in a chain reaction.In other words,we may live on top of a gigantic, “natural”nuclear power plant.
选项
A radical
B traditional
C classical
D conventional
答案
A
解析
本句前面出现的一个词是“tame”,与之对应,应该是“radical”。
转载请注明原文地址:https://ti.zuoweng.com/ti/q7sQKKKQ
相关试题推荐
共用题干 Scientistsworkingonaproblemdonotknowandsometimescan'teveng...
共用题干 Scientistsworkingonaproblemdonotknowandsometimescan'teveng...
共用题干 UnderstandingAutism(孤独症)1Autismisalife-longdevelopmentaldisabili...
共用题干 UnderstandingAutism(孤独症)1Autismisalife-longdevelopmentaldisabili...
共用题干 UnderstandingAutism(孤独症)1Autismisalife-longdevelopmentaldisabili...
共用题干 ApproachestoUnderstandingIntelligencesItpaystobesmart,butweare...
共用题干 ApproachestoUnderstandingIntelligencesItpaystobesmart,butweare...
共用题干 ApproachestoUnderstandingIntelligencesItpaystobesmart,butweare...
Anewgenerationofscientistsbecamefascinatedbydinosaurs.A:intriguedB:infe
40Otherscientists’experimentsaresimilartoHo’sinAthesizeoftheexperi
随机试题
行政收入是政府为公众提供公益服务所取得的收入,一般分为()。 A.规费 B.
(123-125题共用备选答案) A.主要传染源是猪与鼠 B.病人是惟一传染
对口腔颌面部鳞癌,化疗药物可选用 A.争光霉素+长春新碱+喜树碱 B.环磷酰
集料的吸水率就是含水率。()
地陪在接待每一个旅游团(者)之前都要做好()的准备。
某套利者在黄金期货市场上以962美元/盎司的价格买入一份11月份的黄金期货,同时
下列关于“反垄断法中的豁免和适用除外”说法中,正确的是( )。
伤寒发病整个病程均可用于细菌分离培养的标本是
男性,35岁,无高血压家族史,头痛、头晕2个月,伴消瘦、便秘,血压200/120mmHg,胆结石,OGTT提示糖耐量低减。诊断首先考虑A.原发性高血压B.嗜铬
由于监理工程师指令有误而导致施工现场停止施工,产生的费用由()承担。 A.监理工程师 B.施工单位 C.建设单位 D.监理单位