首页
登录
职称英语
The space between the stars is filled with matter that interstellar conditio
The space between the stars is filled with matter that interstellar conditio
游客
2024-01-10
73
管理
问题
The space between the stars is filled with matter that interstellar conditions should prevent from coalescing into solid particle. Yet surprisingly tiny frozen particles, referred to as interstellar grains, do develop in these spaces. These grains are formed out of chemical elements that are synthesized during thermonuclear fusion in stars and supernova explosions.
The study of interstellar grains has been hampered by the inaccessibility of naturally occurring specimens for use in laboratory experiments. To date, the only source of information about interstellar grains is the stellar electromagnetic radiation that reaches the Earth after passing through regions of space containing interstellar grains. By observing the wavelengths scattered and absorbed by the grains scientists have determined that a grain’s internal structure consists of a core composed of silicates (rocklike material) and a mantle composed entirely of organic compounds. It is hypothesized that each grain begins as a silicate “
seedling
” ejected from a mature star. Continuous physical and chemical evolution then occurs in the mantle formed around the seedling. [br] The author uses the term “seedling” most probably in order to
选项
A、suggest that interstellar grains are much smaller than researchers previously assumed
B、suggest the fragility of the process of interstellar grain formation
C、characterize one kind of interstellar grain
D、suggest that most interstellar grains begin as small particles and grow into larger bodies
E、describe the organic nature of interstellar matter
答案
D
解析
本题属于功能题,定位部分的3s版本便是在介绍星际颗粒的形成过程,因此选项D正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3349716.html
相关试题推荐
Itisintriguingthatthosetwoviewsarethoughttobe______;asamatteroffa
Theobtusebelievethattobetruthfulisamatterof______;onlytheartist,th
NIL:QUANTITY::A、quandary:restrictionB、vacuum:matterC、cipher:confusionD、
MILK:NUTRIENT::A、clot:bloodB、matter:elementC、glucose:sugarD、bile:li
Ratherthanallowingthesedramaticexchangesbetweenhercharacterstodevelop
Aten-yearcomparisonbetweentheUnitedStatesandtheSovietUnionintermsof
Theconditionofscholarshipdevotedtothehistoryofwomeninphotographyisc
Thewidelydocumented(i)______betweenthesetwodiseaseshaspromptedscientist
Becauseinsectcommunitiesserveasasortofbarometer,(i)______conditionsin
Aresearcherwhodescribedapeacefulreunionbetweennormallyadversarialchimp
随机试题
TenTipsforReducingStressWhileinCollegeStressissomethin
[originaltext]Interviewer(W)Mr.Fox(M)Now,listentoPartOneofthe
Thedifferencebetweenaliquidandagasisobvious【C1】______thecondition
某健身俱乐部要开发一个信息管理系统,该信息系统的部分关系模式如下:员工(员工身份
焊接盲板(封头)按管件连接计算工程量,其工程计量单位是( )。A.“口” B
下列关于可供出售金融资产的核算,正确的有( )。A.交易费用计入初始确认金额
对青霉素耐药率最高的是A.金黄色葡萄球菌 B.脑膜炎球菌 C.溶血性链球菌
甲的儿子今年即将参加高考,其邻居乙是一个京剧爱好者,每日清晨会定时在房间内练嗓子
牙周袋病理形成始于A:牙龈上皮角化 B:牙周膜内纤维细胞变性 C:牙槽骨破骨
境内单位和个人发生的下列跨境应税行为中,适用增值税零税率的是()。A.向境外单
最新回复
(
0
)