?plutonium

plutonium發(fā)音

英：[plu:?t??n??m]　　美：[plu:?to?n??m]

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plutonium中文意思翻譯

n.钚(放射性元素)

plutonium詞形變化

簡(jiǎn)寫(xiě)符號: Pu |

plutonium常見(jiàn)例句

1 、A radioisotope thermal generator could provide electricity using heat from plutonium decay, but NASA is leaning against this option because it is expensive and controversial.───另一個(gè)提供電力的方法，是利用鈽元素衰變放熱而生電的放射性同位素熱電源，但NASA并不屬意這項方案，因為它既昂貴又具爭議性。

2 、international plutonium storage───國際钚儲存

3 、We're about to have our very own plutonium factory.─── 我們即將擁有自己的钚工廠(chǎng)

4 、North Korea has shut down and is in the process of disabling the Yongbyon reactor complex that produced the plutonium for the nuclear weapon it tested in 2006.───北韓已經(jīng)關(guān)閉同時(shí)也在進(jìn)行拆除寧邊核反應堆的工作。北韓2006年進(jìn)行核武器試驗用的鈽就是在這里生產(chǎn)的。

5 、Two old plutonium disposal plants damaged at once by some unestablished reason.───兩個(gè)遺留有釙的星球被一些不明原因突然破壞。

6 、It is possible to use a plutonium foil as a filter to remove the second-order contamination.───可用钚箔作為過(guò)濾器消除二級干擾。

7 、The age--dependent metabolic modelsin organ and/or body of Tritium, Iodine--131, Caesium--137, radioactive Strontium,Radium and Plutonium were reported.───已報道了氚、碘-131、銫-137、放射性鍶,鐳和钚等核素與年齡有關(guān)的在體內器官的代謝模型。

8 、The effect of external electric field of excited states for Plutonium dihydride[J].───引用該論文 謝安東,蒙大橋,羅德禮,馬美仲,朱正和.

9 、So unseparated plutonium in spent fuel poses a far smaller risk of ending up in the wrong hands.───就算用過(guò)燃料中未分離的鈽落入壞人之手，所造成的風(fēng)險也小得多。

10 、There has been a parallel argument about the lax stock-taking procedures for plutonium.───與此同時(shí)，還有一種關(guān)于钚的倉庫盤(pán)點(diǎn)程序不嚴的觀(guān)點(diǎn)。

11 、UNSC CENTCOM had sent nukes, launched from Slipspace, but plutonium emitted an aura of Cherenkov radiation upon reentering normal space, making all the stealth coatings and lead linings useless.───UNSC司令部曾經(jīng)從斷層空間發(fā)送過(guò)核武器，但在重返正?？臻g時(shí)，钚發(fā)出的切倫科夫輻射使輝光所有的**涂層和鉛襯層失效。

12 、Over the next two decades, India began to construct and operate nuclear reactors, mine uranium, fabricate fuel and extract plutonium.───在隨后的20年中，印度開(kāi)始建立和運行核反應堆，開(kāi)采鈾，制造核燃料和堤取钚。

13 、After you have fuel, and then go to the plutonium storage, and finally reach the reactor and rescue in the region.───你先要經(jīng)過(guò)燃料庫，然后去到钚儲存倉庫，最后終于達到反應堆和拯救該區域。

14 、It deals mainly with North Korea's production of plutonium, concentrated at its Yongbyon facility.───北韓的清單主要涉及北韓在寧邊的設施生產(chǎn)金屬鈽的情況。

15 、More than two tons of this plutonium isotope were generated within the Oklo deposit.───在歐克陸礦床中，有超過(guò)兩公噸的鈽同位素形成。

16 、Gallucci, who is now dean of Georgetown Universitys School of Foreign Service, says one priority is to find out whether North Korea has as much plutonium as it says it does.───加盧奇目前是美國喬治敦大學(xué)外交學(xué)院院長(cháng)。他說(shuō)，首先需要解決的一個(gè)問(wèn)題是確認北韓是否擁有他們自己所說(shuō)的那么多的金屬鈽。

17 、The computer simulation model for the separation of uranium and plutonium using the electro reduction pulsed column was established.───建立了電還原脈沖柱分離鈾钚的模擬計算模型,提出了該模型的數值計算算法。

18 、The aftertreatment includes the metal all round eliminate lack fuel to cover case, fuel of deliquescent in hot acid lack, depart uranous, plutonium and trash chemistry again next.───后處理包括除去乏燃料四周的金屬套殼 ,在熱酸中溶解乏燃料 ,然后再將鈾、钚和廢物化學(xué)分離。

19 、Iran says it is fiddling with uranium and plutonium to produce more electricity.───伊朗輕描淡寫(xiě)的說(shuō)利用鈾和钚可以更多發(fā)電。

20 、Test Method for Plutonium by Controlled-Potential Coulometry───控制電勢庫侖法測定钚的試驗方法

21 、Is plutonium in I thinking that news says a nuclear weapon, that Nature is nonexistent , is to refine out just now with the centrifugal machine , the gravity keeping apart?───我看新聞?wù)f(shuō)核武器中的钚，是自然界不存在的，是用離心機，隔離地球引力才提煉出來(lái)的？

22 、Plan to do not have legitimate reason and corresponding social benefit to plutonium of L WR proceed departs and execute MOX fuel.───為 L WR繼續進(jìn)行钚分離和實(shí)行 MOX燃料計劃沒(méi)有正當的理由及相應的社會(huì )效益。

23 、You want your plutonium, this is the price.─── 你想要拿到钚核 這就是代價(jià)

24 、Gunner talked like a peacenik but Trout knew “Plutonium Jack” would never hesitate to pull the nuclear trigger if he had to.───剛納說(shuō)起話(huà)來(lái)真很像那幫成天搞反戰示威的人，但陶特清楚，只要需要，這個(gè)"钚杰克"絕對會(huì )眼也不眨地按下核按鈕。

25 、Like Galileo, Cassini is powered by the natural decay of the radioactive element plutonium, which generates heat that is then converted to electricity.───如同伽利略號，卡西尼號的能源來(lái)自放射性元素鈽的自然衰變，產(chǎn)生熱后再轉換成電。

26 、A longer-term option could involve recycling all the transuranics (plutonium is one example of a transuranic element), perhaps in a so-called fast reactor.───一種比較長(cháng)遠的做法是，在再次循環(huán)中使用所有的超鈾元素（鈽就是一種超鈾元素），可能會(huì )用在快中子反應器里。

27 、North Korea now saying they will weaponize all of their plutonium, also saying they will enrich uranium.───并稱(chēng)將收集國家所有的钚來(lái)增大鈾的產(chǎn)量。

28 、If Iran agreed to halt its uranium and plutonium activities, and America agreed not to attack, might that open the way to direct talks that could help finesse the nuclear problem for good?───如果伊朗同意停止提煉鈾和钚的活動(dòng)，而美國也同意不發(fā)動(dòng)攻擊，或是打開(kāi)直接談判的大門(mén)，也許會(huì )把這個(gè)核問(wèn)題化害為利。

29 、On the other hand, to 1996 till the end of the year, japan is in abroad already of the aftertreatment but fission plutonium about 10.5 ton, these plutonium still stay in abroad.───另一方面 ,到 1996年年底為止 ,日本在國外已后處理的可裂變钚大約 10 .5噸 ,這些钚仍留在國外。

30 、one tonne of plutonium extracted from spent nuclear fuel───從廢核燃料中提取的一噸

31 、These names come from the fact that the source of energy the nucleus，or core，of the atom，Nuclear fuels much as plutonium and uranium give off heat energy when fission occurs.───當核燃料，例如釙和鈾，發(fā)生核裂變時(shí)釋放出熱能（這些燃料中原子發(fā)生分裂）。

32 、Catalyzed electrolytic plutonium oxide issolution───催化電解溶解钚的氧化物

33 、plutonium reprocessing programme───對钚進(jìn)行后期處理的項目

34 、Possessed enough plutonium for one or two nuclear weapons───擁有足夠制造一至兩枚核武的鈽

35 、The Yongbyon facilities include a5 MW graphite-moderated reactor and a plant used to reprocess spent nuclear fuel from this reactor, including the extraction from it of weapons-grade plutonium.───寧邊的核設施包括5兆瓦的石墨慢化反應堆以及后處理廠(chǎng)在內的一些已用乏燃料（過(guò)的核燃料后處理）處理設施，還有為了研發(fā)核武器而進(jìn)行钚提取的設備。

36 、Pyongyang has already closed one plutonium reactor, but there are now fears it may also be pursuing uranium enrichment.───平壤已經(jīng)關(guān)閉了一個(gè)钚反應器，但是當心他們會(huì )繼續研究鈾能源。

37 、From now on, I'm the only one who touches the plutonium.─── 從現在起 只有我可以接觸钚

38 、DO YOU KNOW WE THE SEPARATED PLUTONIUM IS?───你知道分離钚在哪兒?jiǎn)?

39 、Gary Milhollin, director of the Wisconsin Project on Nuclear Arms Control, in commenting Iran's true intention to start working on a 40-megawatt heavy water reactor that will make plutonium.───伊朗開(kāi)始建造一40兆瓦的重水反應堆,以生產(chǎn)钚元素。威斯康辛核武器控制項目主任米爾赫林就其真正意圖作了上述評析。

40 、Those who possess a source of plutonium shall register it at the AEC.───其持用者，應向原子能委員會(huì )登記。

41 、Dangerous emissions radiate from plutonium───危險的輻射物從钚放射出。

42 、tricyclopentadienyl-nicotine plutonium───三(環(huán)戊二烯)**钚

43 、The escape of neutrons occurs at the exterior of the uranium(or plutonium)material.───中子的逸漏發(fā)生于鈾（或钚）塊的外表面。

44 、If the Russians can get the "foreign aid" to dispose of their excess Plutonium from the PRC, then Congress won't have to supply it.───如果俄羅斯能夠從中國獲得“外援”以處理他們過(guò)剩的钚，那么國會(huì )不會(huì )被迫滿(mǎn)足俄的要求。

45 、In this paper the power flow, tritium and plutonium fuel cycle and the possibility of earlier application of the hybrid reactor as fusion energy source have been introduce briefly.───對慣性約束混合堆的功率循環(huán)，氚钚生產(chǎn)的燃料循環(huán)和混合堆作為聚變能源的前期應用的可能性作了簡(jiǎn)要的介紹。

46 、North Korea has taken significant steps toward stopping and disabling its means of plutonium production under the terms of a deal reached early last year.───北韓按照去年初達成的協(xié)議條款，采取有力步驟向中止并廢棄金屬鈽生產(chǎn)設施邁進(jìn)。

47 、But a stronger impact could have sent both subs and their crews to the bottom and possibly dispersed plutonium into surrounding waters.───但更強烈的沖擊可能會(huì )把潛艇和船員一起送到海底，并且把钚混進(jìn)周?chē)暮Ｋ铩?/p>

48 、Four years ago, President George Bush urged the NSG to bar the sale of uranium and plutonium technologies to any country that at the time did not already possess “full-scale, functioning” plants.───四年前，美國總統喬治布什迫切要求核供應集團禁止向那些暫時(shí)未擁有“全能性核處理工廠(chǎng)”的國家提供鈾和钚的處理技術(shù)。

49 、One possible method of measurement of isotopic composition and mass for plutonium is discussed and its feasibility in theory is demonstrated by the MCNP4B package in this paper.───摘要利用MCNP4B程序，通過(guò)一個(gè)實(shí)例探討了钚的同位素成分及總質(zhì)量測量的理論可行性。

50 、The rest of the spent fuel is made of hot fission products (3.4 percent) and long-lived actinides such as plutonium (1 percent).───剩下的核廢料是由熾熱的裂變產(chǎn)物（占3.4%）和諸如钚元素等衰敗期極長(cháng)的錒系元素（占1%）。

51 、Iranian state media reports Monday's inspection of the Arak facility took five hours. The facility will produce plutonium once it is completed.───伊朗國家媒體報導說(shuō)，星期一對阿拉克設施的查看進(jìn)行了5個(gè)小時(shí)．這座核設施建成后將生產(chǎn)鈽。

52 、Abstract The extraction of americium,plutonium and uranium by dicyclohexano 18 crown 6(DCH18C6)/1 octanol from HNO 3 solution and simulated HLLW are studied.───摘要 研究了二環(huán)己基18 冠6（DCH18C6）-正辛醇從硝酸溶液和模擬高放廢液中镅、钚、鈾的萃取。

53 、Processing of spent fuel with high burn-up should take special measure in order to avoid heavy radiolytic degradation of the solvent and the criticality of plutonium.───當處理高燃耗的乏燃料時(shí),應采取特別措施,以避免造成溶劑的嚴重輻解和钚的臨界問(wèn)題。

54 、The other is to reprocess plutonium -- the method chosen by North Korea.───北韓選擇的是第二種方法。

55 、plutonium sulphate tetrahydrate───四水合硫酸钚

56 、If we mankind could ever get to Mars, we might first of all use plutonium to heat up the planet to a more earth-like temperature so as to make it suitable for humans to live on.───如果我們人類(lèi)一旦登上火星，就可能首先用钚來(lái)把火星加熱到更像地球的溫度，以使火星能適合人類(lèi)居住。

57 、According to the BBC, the United Nations nuclear monitors, said Vienna's Sebo Seibersdorf laboratory in the south of plutonium in the rising pressure of the leak occurred, a store between pollution.───據英國廣播公司報道，聯(lián)合國核監督人員說(shuō)，維也納南部的塞波斯多夫實(shí)驗室的钚元素在壓力不斷增高的情況下發(fā)生泄漏，污染了一個(gè)儲存間。

58 、Analysts say that would allow the reclusive Communist state to extract plutonium from the reactor's fuel rods - giving it additional fuel with which to build nuclear weapons.───分析家說(shuō)那些隱蔽的共產(chǎn)主義國家可以從反應堆的能量棒上提取钚，這樣可以提供額外的能量來(lái)建立核武器。

59 、No one comes between you and that plutonium.─── 絕不能讓任何人阻止你拿到钚核

60 、You have no idea what we'll find out when the plutonium arrives.─── 你不知道等钚到了之后 我們能發(fā)現什么

61 、It has shut down, and is well along in the process of permanently disabling, the reactor complex at Yongbyon from which it derived the plutonium for its small arsenal of nuclear weapons.───北韓已經(jīng)關(guān)閉寧邊核反應堆，并且正按照進(jìn)程，達成這個(gè)核反應堆的永久終止運轉。北韓擁有一個(gè)小型的核武軍火庫，平壤通過(guò)寧邊核反應堆生產(chǎn)發(fā)展核武所需要的鈽。

62 、plutonium bearing fuel assembly───含钚燃料組件

63 、President Bush has said he welcomes North Korea's recent declaration of its plutonium enrichment activities, and the destruction of the cooling tower at its Yongbyon reactor.───在首爾，布什將同李明博討論安全和金融問(wèn)題。

64 、Reprocessing can potentially recover up to 95% of the remaining uranium and plutonium in spent nuclear fuel, putting it into new mixed oxide fuel.───再處理過(guò)程能夠在燃燒核燃料時(shí)消耗大約95%殘留的鈾和钚，形成新的氧化物核燃料。

65 、Director branch did not save the complete detailed list of the trash inside shaft, do not be clear about the plutonium in trash and uranous exact content so.───主管部門(mén)沒(méi)有保存豎井內廢物的完整清單 ,所以不清楚廢物中钚和鈾的確切含量。

66 、I'd give him all the plutonium he wants.─── 他要多少钚材料我就給多少

67 、It also submitted a declaration of its nuclear activities, limited mainly to Yongbyon's plutonium production.───北韓也遞交了一份核活動(dòng)清單，主要是關(guān)于寧邊的鈽制造。

68 、It threatens to rebuild Yongbyon and start making weapons-grade plutonium again.───它威脅說(shuō)要重建寧邊核設施并重新開(kāi)始制造武器級別的釙。

69 、However, the actual weight of uranium or plutonium in such a weapon is greater than this amount.───可是，在一枚那樣的核武器中，鈾或钚的實(shí)際重量要比這個(gè)數字大得多。

70 、He said there has been progress, noting North Korea's recent declaration of its plutonium enrichment activities and the destruction of the cooling tower at its Yongbyon reactor.───布什說(shuō)：“我無(wú)法預測北韓**如何決策。我不知道他會(huì )怎樣做。但是我知道，解決這個(gè)問(wèn)題的最好方式是其他五個(gè)國家步調完全一致?！?/p>

71 、North Korea officials said they were enriching uranium and would weaponize all plutonium, according to KCNA, the state-run North Korean news agency.───“不管美國如何試圖采取何種制裁和封鎖，北韓恃核而驕，將更不退縮?！?/p>

72 、Both sides are expressing concern over North Korean statements on Friday that Pyongyang is continuing to extract plutonium from spent nuclear fuel for material useable in weapons.───博斯沃思從星期五一直在韓國首都逗留，同包括韓國的首席核談判代表魏圣洛以及統一部長(cháng)官在內的官員舉行了一系列會(huì )談。

73 、"I know for sure that North Korea has the plutonium that they need for a nuclear weapon," he said.───埃爾巴拉迪說(shuō)，“我敢肯定地說(shuō)，北韓擁有制造核武器的鈽。

74 、pressed plutonium oxide (PPO)───壓制過(guò)的氧化钚

75 、He'll be taking over the investigation into the missing plutonium.─── 他會(huì )接管調查 尋找失蹤的钚

76 、Catalyzed Electrolytic Plutonium Oxide Dissolution───催化電解法溶解钚的氧化物

77 、But the large aftertreatment that no matter the plutonium of which kinds of form asks to use to have strict screen,reclaims factory.───但回收無(wú)論哪種形式的钚都要求利用一個(gè)有嚴格屏蔽的大型后處理廠(chǎng)。

78 、North Korea's plutonium program has been by far its largest nuclear effort over many decades, and we believe our policy could verifiably get the regime out of the plutonium-making business.───北韓的钚項目是其幾十年來(lái)最大規模的核項目，遠遠超過(guò)其他任何項目。我們相信，我們的政策能夠以可核實(shí)的方式使北韓政權不再生產(chǎn)钚。

79 、The Yongbyon facilities include a 5MW graphite-moderated reactor and a plant used to reprocess spent nuclear fuel from this reactor, including the extraction from it of weapons-grade plutonium.───寧邊的核設施包括5兆瓦的石墨慢化反應堆以及后處理廠(chǎng)在內的一些已用乏燃料（燒過(guò)的核燃料后處理）再處理設施，還有為了研發(fā)核武器而進(jìn)行钚提取的設備。

80 、China's main nuclear weapons design facility lies nearby in Mianyang and its main facility for processing plutonium for nuclear weapons in Guangyuan. The quake damaged both cities.───中國主要的核武器設計設施位于綿陽(yáng)附近，而核武器用钚的處理設施則位于廣元。地震對以上兩個(gè)地區都造成了破壞。

81 、Sugar sugar, which is not exactly plutonium.─── 糖 糖 就是 糖可不是钚

82 、low-enriched uranium and plutonium───低濃縮鈾和钚

83 、But first Iran must freeze uranium work at today's level and, if talks progress, suspend its uranium and plutonium effort.───不過(guò)前提是伊朗必須在現有基礎上凍結鈾濃縮技術(shù)，如果會(huì )談取得進(jìn)展，伊朗則需中止鈾和钚濃縮的努力。

84 、The detector can been used to determine the burnup, cooling time and the contents of whole plutonium and whole fission material in spent fuel assemblies of the PWR and BWR types at a reprocessing and storage facility.───叉形探測器可用于后處理和貯存工廠(chǎng)中PWR和BWR型的乏燃料組件的燃耗、冷卻時(shí)間、總钚和總裂變物質(zhì)含量的測定。

85 、He used her to squeeze the plutonium out of you.─── 他利用她從你這里設法獲得钚材料

86 、Produce and use of MOX fuel make the imposition of American taxpayer pay possibly still far outclass the imposition solidify of the plutonium in trash.───MOX燃料的生產(chǎn)和使用還可能使美國納稅人繳納的稅款遠遠高于將廢物中钚固化的稅款。

87 、Their next goal is to create element 120 by beaming iron atoms (26 protons) at a plutonium target (which has 94 protons).───他們的下一個(gè)目標是創(chuàng )造120號元素，使用鐵原子（26個(gè)質(zhì)子）轟擊钚（94個(gè)質(zhì)子）。－－钚（讀音：布）。

88 、I'll give him all the plutonium he wants.─── 他要多少钚材料我就給多少

89 、Analysis of Sub-picogram Plutonium by Isotope Mass Spectrometry───亞皮克量級钚的質(zhì)譜分析技術(shù)

90 、plutonium 238 fueled pacemaker───238钚原子能起搏器

大學(xué)pu不達標可以畢業(yè)嗎

大學(xué)pu不達標不可以畢業(yè)，大學(xué)pu分是第二課堂學(xué)分。

以浙江大學(xué)為例，根據《浙江大學(xué)本科生第二課堂學(xué)分管理辦法》第五條 根據《關(guān)于制訂 2006—2008 級本科專(zhuān)業(yè)培養方案和指導性教學(xué)計劃的原則意見(jiàn)》（浙大發(fā)教[2006]1 號）規定，本科學(xué)生在完成必修、選修和實(shí)踐教學(xué)環(huán)節學(xué)分外，必須修讀第二課堂活動(dòng)至少 4 個(gè)學(xué)分方能畢業(yè)。

學(xué)生可以通過(guò)參加各類(lèi)學(xué)科競賽、科研訓練和發(fā)表學(xué)術(shù)成果等方式獲得以上學(xué)分。學(xué)生第二課堂活動(dòng)的表現作為《實(shí)踐能力與素質(zhì)拓展》課的成績(jì)記入學(xué)生檔案。

pu

钚（Plutonium ），原子序數為94，元素符號是Pu，是一種具放射性的超鈾元素。半衰期為24萬(wàn)5千年。它屬于錒系金屬，外表呈銀白色，接觸空氣后容易銹蝕、氧化，在表面生成無(wú)光澤的二氧化钚。

钚有六種同位素和四種氧化態(tài)，易和碳、鹵素、氮、硅起化學(xué)反應。钚暴露在潮濕的空氣中時(shí)會(huì )產(chǎn)生氧化物和氫化物，其體積最大可膨脹70%，屑狀的钚能自燃。它也是一種放射性毒物，會(huì )于骨髓中富集。因此，操作、處理钚元素具有一定的危險性。

钚的半衰期是多少年

钚的半衰期是8.2×107年。

钚plutonium一種化學(xué)元素?；瘜W(xué)符號Pu，原子序數94，屬周期系ⅢB族，為錒系元素的成員和人工放射性元素。半衰期最長(cháng)的同位素是钚244。1940年美國G.T.西博格、E.M.麥克米倫、J.W.肯尼迪和A.C.沃爾用152.4厘米回旋加速器加速的16兆電子伏氘核轟擊鈾時(shí)發(fā)現钚238。第二年又發(fā)現钚的最重要的同位素钚239。

在自然界中只找到兩種钚同位素，一種是從氟碳鈰鑭礦中找到的微量钚244，它具有足夠長(cháng)的半衰期，可能是地球上原始存在的。另一種是從含鈾礦物中找到的钚239，是鈾238吸收自然界里的中子而形成的。其他钚同位素都是通過(guò)人工核反應合成的。已發(fā)現的有質(zhì)量數232～246的钚同位素。

資料拓展：

钚彈爆炸是什么原理

現代原子彈由三個(gè)主要部分組成：分別是主級，二次級和輻射容器。主級是一個(gè)由钚組成的小球，是炸彈的核心部分。隨后這個(gè)核心被次要成分包裹，這種次要成分一般是一些化學(xué)質(zhì)，最后在這層質(zhì)外層用一層鈾殼包圍。

起爆時(shí)中間部分的化學(xué)率先被觸發(fā)，它會(huì )引起內爆，產(chǎn)生的爆炸能量可以在瞬間擠壓中間的钚芯從而導致钚芯的密度瞬間增加，這種人為迫使原子疊加在一起產(chǎn)生自由的中子，從而引發(fā)钚原子核在鏈式反應中發(fā)生裂變從而釋放出巨大能量。

這種核彈被形象地稱(chēng)作三位一體，最早的三位一體核彈重約一萬(wàn)磅，現如今科學(xué)技術(shù)發(fā)展已經(jīng)能將核彈縮減到重250磅，而體積也僅有一個(gè)手提箱大小。

钚和毒性

钚具有放射性，但你可能永遠也接觸不到它。钚雖然存在于自然界中，但是極其微量，大儲量高純度的钚沒(méi)有天然來(lái)源，它必須是通過(guò)人造才能產(chǎn)出，但假如人們接觸或者吸入了它時(shí)，這些钚會(huì )困在人們的肺部，并會(huì )迅速轉移到身體的骨骼和臟器中，并最終導致中毒死亡。钚是迄今為止人類(lèi)已知毒性最大的放射性毒藥之一。