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
考研
Radiation occurs from three natural sources: radioactive material in the environment, such as in soil, rock, or building materia
Radiation occurs from three natural sources: radioactive material in the environment, such as in soil, rock, or building materia
admin
2010-09-06
53
问题
Radiation occurs from three natural sources: radioactive material in the environment, such as in soil, rock, or building materials; cosmic rays; and substances in the human body, such as radioactive potassium in bone and radioactive carbon in tissues. These natural sources account for an exposure of about 100 millirems a year for the average American.
The largest single source of man-made radiation in medical x-rays, yet most scientists agree that hazards from this source are not as great as those from weapons test fallout, since strontium-90 and carbon-14 become incorporated into the body, hence delivering radiation for an entire lifetime. (46)
The issue is, however, by no means uncontroversial; indeed, the last two decades have witnessed intensified examination and dispute about the effects of low-level radiation.
A survey conducted in Britain confirmed that an abnormally high percentage of patients suffering from arthritis of the spine who had been treated with x-rays contracted cancer. Another study revealed a high incidence of childhood cancer in cases where the mother had been given x-rays. (47)
These studies have pointed to the need to re-examine the assumption that exposure to low linear energy transfer presented only a minor risk.
Recently, examination of the death certificates of former employees of a West Coast plant which produces plutonium for nuclear weapons revealed markedly higher rates for cancers of the pancreas, lung, bone marrow and lymph systems than would have been expected in a normal population.
(48)
While the National Academy of Sciences committee attributes these differences to chemical or other environmental causes, rather than radiation, other scientists maintain that any radiation exposure, no matter how small, leads to an increase in cancer risk.
(49)
It is believed by some that a dose of one rem, if sustained over many generations, would lead to an increase of one percent in the number of 1,000 disorders per million births.
In the meantime, regulatory efforts have been disorganized, fragmented, and inconsistent, characterized by internecine strife and bureaucratic delays. A Senate report concluded that coordination of regulation among involved departments and agencies was not possible because of jurisdictional disputes and confusion. (50)
One Federal agency has been unsuccessful in its efforts to obtain sufficient funding and manpower for the enforcement of existing radiation laws, and the chairperson of a panel especially created to develop a coordinated Federal program has resigned.
选项
答案
一家联邦机构为了强化实施现有的辐射法律,竭尽全力去获取充足的资金和人力,但却失败了。并且一个旨在促进协调联邦计划的专题小组的主席已经辞职了。
解析
转载请注明原文地址:https://kaotiyun.com/show/zoZ4777K
0
考研英语一
相关试题推荐
Innovationiskeytobusinesssurvival,andcompaniesputsubstantialresourcesintoinspiringemployeestodevelopnewideas.T
Thecostsassociatedwithnaturaldisastersareincreasingrapidly.Asaresult,officialsingovernmentandindustryhavefocus
Byeducation,Imeantheinfluenceoftheenvironmentupontheindividualtoproduceapermanentchangeinthehabitsofbehavio
Nameshavegainedincreasingimportanceinthecompetitiveworldofhighereducation.Ascollegesstriveformarketshare,they
Nameshavegainedincreasingimportanceinthecompetitiveworldofhighereducation.Ascollegesstriveformarketshare,they
Nameshavegainedincreasingimportanceinthecompetitiveworldofhighereducation.Ascollegesstriveformarketshare,they
Theeraofcheapandconvenientsourcesofenergyiscomingtoanend.Atransitiontomoreexpensivebutlesspollutingsources
BankruptcyratesintheU.S.havebeengrowingformorethantwodecadesdespitegenerallyrisinglevelsofpersonalincome.The
Threemakesatrend.TheWashingtonPostCo.FridayannouncedthatitwouldlooktosellitsheadquartersbuildingindowntownW
Thegrowthspeeialisationinthe19thcenturymightbemoreclearlyseeninsciencessuchas______.Theauthorwritesofthed
随机试题
A.宗气内虚B.宗气外泄C.心气已绝D.心阳不足虚里按之搏动迟弱,为
下列不是卵巢转移癌转移途径的是
A.关节疼痛,游走不定B.关节剧痛,部位固定C.关节肿胀,重着而痛D.关节肿大,僵硬变形E.关节红肿热痛痹证之行痹的特征为
A、低血糖B、粒细胞缺乏症,再生障碍性贫血,血小板下降性紫癜C、肝肾功能损害D、嗜睡疲劳E、头痛心悸震颤含马来酸氯苯那敏成分的中成药易致
无机结合料稳定基层采用集中拌和法施工时,以下()施工要求是正确的。
下列关于税收饶让的表述,正确的是()。
资产负债表中的“固定资产”项目包括“固定资产清理”的账面价值。()
SendingE—mailstoProfessorsOnestudentskippedclassandthensenttheprofessorane-mail______(1)forcopiesofherteaching
据我国《刑事诉讼法》的规定,除法律特别规定的以外,公安机关负责对刑事案件的侦查、拘留、预审等。人民法院负责对刑事案件的审讯,人民检察院负责检察,检察机关直接受理的案件的侦查、提起公诉等。此外还负责()。
接收并阅读由xuexq@mail.neea.edu.cn发来的E-mail,并按E-mail中的指令完成操作。
最新回复
(
0
)