首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Space is a dangerous place, not only because of meteors (流星) but also because of rays from the sun and other stars. The atmosphe
Space is a dangerous place, not only because of meteors (流星) but also because of rays from the sun and other stars. The atmosphe
admin
2009-01-05
10
问题
Space is a dangerous place, not only because of meteors (流星) but also because of rays from the sun and other stars. The atmosphere again acts as our protective blanket on earth. Light gets through, and this is essential for plants to make the food which we eat. Heat, too, makes our environment endurable. Various kinds of rays come through the air from outer space, but enormous quantities of radiation from the sun are screened off. As soon as men leave the atmosphere they are exposed to this radiation but their spacesuits or the walls of their spacecraft, if they are inside, do prevent a lot of radiation damage.
Radiation is the greatest known danger to explorers in space. The unit of radiation is called" rem". Scientists have reason to think that a man can put up with far more radiation than 0.1 rem without being damaged; the figure of 60 rems has been agreed on. The trouble is that it is extremely difficult to be sure about radiation damage-a person may feel perfectly well, but the cells of his or her sex organs may be damaged, and this will not be discovered until the birth of deformed (畸形的) children or even grandchildren. Missions of the Apollo flights have had to cross belts of high radiation and, during the outward and return journeys, the Apollo crew accumulated a large amount of rems. So far, no dangerous amounts of radiation have been reported, but the Apollo missions have been quite short. We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere, working in a space laboratory. Drugs might help to decrease the damage done by radiation, but no really effective ones have been found so far.
The best title for this passage would be______.
选项
A、The Atmosphere and Our Environment
B、Research on Radiation
C、Effects of Space Radiation
D、Importance of Protection Against Radiation
答案
C
解析
主旨题。文章第一段指出,太空是一个危险的地方主要是因为太空辐射。离开大气层的宇航员虽有宇航服及宇航船的保护,但也免不了接受辐射。文章第二段指出辐射危害在短期内难以觉察,药物可以减轻辐射危害,但真正有效的药物迄今还未被发现。由此可以看出文章谈及的主要是太空辐射的后果方面的事,所以选项C为正确答案。
转载请注明原文地址:https://kaotiyun.com/show/mqBK777K
0
专业英语四级
相关试题推荐
Thesituationcomedyhasprovedtoaremarkablydurablecommercialtelevisionformat.
Losingweightiseasierwhenthereismoneyontheline,U.S.researcherssaidonTuesday.Theysaidweight-lossprogramsthat
Forpeoplesufferingfromdepression,theadviceisusuallythesame:seekhelp.Thissimple-soundingdirective,moreover,is【M1
Forpeoplesufferingfromdepression,theadviceisusuallythesame:seekhelp.Thissimple-soundingdirective,moreover,is【M1
Issuesconcerninghumanlearningareamongthecriticaltopicsineducationalpsychology,childdevelopment,andcognitivescie
Themostconsistentlyidentifiedteachereffectivenessvariableistimeontask.Thatis,themoretimethatstudentsspendon
Bullyinghasalwaysexistedinschools.Inrecentyears,abetterunderstandingofthetraumaticeffectsitcanhaveonitsvict
PassageTwo(1)Everyoneintoday’ssuperchargedworkplacesexperiencesstress.Yetexecutiveandprofessionalwomenconsis
Asmanyas40%ofuniversitylanguagedepartmentsarelikelytoclosewithinadecade,theformergovernmentadviserchargedwi
随机试题
阅读下面的文字:艺术家估定事物的价值,全以它能否纳人和谐的整体为标准,往往出于一般人意料之外。他能看重一般人所看轻的,也能看轻一般人所看重的。在看重一件事物时,他知道执着;在看轻一件事物时,他也知道摆脱。艺术的能事不仅见于知所取,尤其见于知所舍。
女性,56岁,久站或咳嗽时左侧腹股沟区胀痛1年,有慢性支气管炎病史3年,近1个月咳嗽加重。查体:站立时左腹股沟韧带下方内侧突起半球形肿物平卧时缩小,咳嗽时无明显冲击感。如果行手术治疗,此病人最适宜的手术方法应选择
肝硬化患者最常见的并发症是()肝硬化患者最严重的并发症是()
药用部分是动物的干燥全体的药材有
B公司为一上市公司,适用的企业所得税税率为25%,相关资料如下:资料一:2012年12月31日发行在外的普通股为10000万股(每股面值1元),公司债券为24000万元(该债券发行于2008年年初,期限10年,每年年末付息一次,利息率为5%),该年息
()是基于被保险人的一定关系而享有一定保险利益的主体。
42岁的丁成是一名货车司机,三年前的一天,在送货途中不幸遭遇车祸,导致下半身瘫痪,只能依靠轮椅行动。这对丁成来说是一个沉重的打击,他认为自己不仅失去了行走能力,连工作能力都没有了。如此一来,全家人的生活重担落在了妻子一个人身上,这让家里的经济状况迅速恶化。
城乡最低生活保障属于()领域社会工作的主要内容。
Onceuponatime,inasolarsystemthereweretwoplanets.TheirnameswereYeeandLan,andtheylovedeachotherverymuch.B
PackagingItissaidthatthepublicandCongressionalconcernaboutdeceptivepackagingrumpusstartedbecauseSenatorHart
最新回复
(
0
)