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
31
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
Theyusuallyhavelessmoneyattheendofthemonththan____atthebeginning.A、
Googlemustbethemostambitiouscompanyintheworld.Itsstatedgoal,"to
Encouragementandpraisecancomeinmanyforms,andsomewaysarebetterfo
AboutGlassandHowItIsMade1.Obsidian■Akindof【T1】_______
按照不同的分类标准,电子商务有哪些不同的类型?
以艺术作品的存在方式为分类依据,不属于空间艺术的是()。A.戏曲 B.绘画
共用题干 王明委托通达房地产经纪公司(以下简称通达公司)为其购买1套二手房,并
可供临床治疗选择使用,疗效好,同类药品中比“甲类目录”药品价格略高的药品纳入的保
我国2013年国内生产总值为59万亿元,财政支出为14万亿元,2014年国内生产
甲公司为增值税一般纳税人,2×09年至2×14年发生的有关的交易或事项如下:
最新回复
(
0
)