| 单词 | fissile |
| 例句 | The discovery of a fissile isotope that could be separated from its parent by chemical means might quell the skepticism still bogging down the uranium program. Big Science 2015-07-07T00:00:00Z But naturally occurring uranium also contained U-235, which was much more fissile—highly likely to split after absorbing a neutron of almost any speed. Big Science 2015-07-07T00:00:00Z From the slugs of irradiated uranium, fissile plutonium would be extracted at a second plant ten miles away, eventually to be sent on its way to Los Alamos. Big Science 2015-07-07T00:00:00Z While the Mark I was still undergoing this shakedown procedure, Lawrence spent his time soothing official doubts about the MTA by citing the continuing threat of a shortage of fissile material. Big Science 2015-07-07T00:00:00Z It makes sense that television has become obsessed with pivotal moments and creative and scientific breakthroughs; the medium is in the middle of its own fissile chain reaction. ‘Manh(a)ttan,’ Atomic Bomb Drama, on WGN 2014-07-24T04:00:00Z Former statesmen and intelligence analysts appear, warning of an al Qaeda bomb that might one day be built from unregulated fissile materials on black markets. From bomb silo to big screen, an anti-nuclear quest 2011-06-17T06:56:07Z The further down the social scale you go, the more fissile American families are. The new merry-go-round 2014-10-02T04:00:00Z The rise of global terrorism, the expanding nuclear club, the increased availability of fissile material on the black market: all point to a higher likelihood of nuclear attack than ever before. Film: Two New Films About the Nuclear Threat 2010-07-18T01:33:00Z The splintered, the fissile, the ruderal: these are the Ness's textures. Robert Macfarlane's Untrue Island: the voices of Orford Ness 2012-07-08T18:01:01Z Many successful writers forget the “you” part of the equation, the uniquely fissile power of the reader. In Fiction, Martin Amis Summons His Literary Friends and Role Models 2020-10-26T04:00:00Z Washington, however, is preparing to conduct next year at the Nevada Test Site two so-called subcritical experiments involving fissile materials in amounts too small to ignite a nuclear explosion. Russia accuses US of nuclear testing site activity, says it won't test unless US does 2023-10-10T04:00:00Z President Joe Biden’s failure to revive it, Iran could make the fissile material for one bomb in 12 days or so, according to U.S. estimates, down from a year when the accord was in force. Britain, France, Germany to retain ballistic, nuclear sanctions on Iran 2023-09-14T04:00:00Z “I don’t think they are short of fissile materials,” said Mr. Lankov. North Korea’s new missile tests exposes Kim’s limited options 2023-07-12T04:00:00Z However, Iran is also pursuing “research and development activities that would bring it closer to producing the fissile material needed for completing a nuclear device following a decision to do so,” the report said. US intelligence assessment says Iran not currently developing nuclear weapons 2023-07-10T04:00:00Z President Joe Biden's failure to revive it, Iran could make the fissile material for one bomb in 12 days or so, according to U.S. estimates, down from a year when the accord was in force. Exclusive: Europeans plan to keep ballistic missile sanctions on Iran 2023-06-28T04:00:00Z President Donald Trump exited the nuclear pact and reimposed sanctions on Iran, which in response breached the deal by rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges. Iran holds talks with EU mediator Mora in Qatar 2023-06-21T04:00:00Z The isotope U-235 is fissile, which means that it can be split in a reaction that releases a lot of energy. The US will send depleted uranium munitions to Ukraine — an expert explains their health effects 2023-06-17T04:00:00Z Israeli and Western officials say it could switch from enrichment at 60% fissile purity to 90% - weapons-grade - within a few weeks. Israel accuses U.N. nuclear watchdog of 'capitulating' to Iran 2023-06-04T04:00:00Z It would be far harder if there were dozens of fissile armed groups claiming a seat at the table. Sudan crisis: Mediators over a barrel in mission to end fighting 2023-05-07T04:00:00Z In a real weapon, conventional explosives ringing an actual pit would implode the plutonium to a critical density, triggering an explosive fissile chain reaction. Trust but verify: Can the U.S. certify new nuclear weapons without detonating them? 2023-04-20T04:00:00Z Some believe that Pyongyang has both a limited stockpile of fissile materials and no need to prove a well-tested capability. Jitters in Japan as latest North Korean missile takes flight 2023-04-13T04:00:00Z "These developments seem to reflect Kim Jong Un's recent directive to increase the country's fissile material production to expand its nuclear weapons arsenal," the report added, referring to the North Korean leader. High activity spotted at North Korea nuclear complex after Kim's bomb-fuel order, report says 2023-04-01T04:00:00Z It has also test-detonated six nuclear devices, though the extent of its fissile material stockpile remains secret. North Korea claims test of Russia-style unmanned underwater nuke 2023-03-24T04:00:00Z Previous versions of the policy focused on securing fissile material commonly used in nuclear weapons such as the ones the United States used against Hiroshima and Nagasaki in 1945. New U.S. Policy Focuses on Securing Radioactive Materials Used in Industries 2023-03-02T05:00:00Z While U.S. officials say Iran has grown closer to producing fissile material they do not believe it has mastered the technology to actually build a bomb. Iran can make fissile material for a bomb 'in about 12 days' - U.S. official 2023-02-28T05:00:00Z In their latest annual report, the monitors also said Pyongyang continued producing nuclear fissile materials at its facilities and launched at least 73 ballistic missiles, including eight intercontinental ballistic missiles last year. Exclusive: Record-breaking 2022 for North Korea crypto theft, UN report says 2023-02-06T05:00:00Z There is little doubt that high-tech, prosperous South Korea, possessing home-grown missile technologies and fissile materials from nuclear power plants, is capable of going nuclear. North Korean defector lays out South Korean rationale for seeking nukes 2023-02-03T05:00:00Z Experts say Iran could potentially raise the fissile purity of its uranium to weapons-grade in short order. Israeli minister sees possible attack on Iran "in two or three years" 2022-12-28T05:00:00Z In addition, Woodward said, “Iranian nuclear breakout time has reduced to a matter of weeks, and the time required for Iran to produce the fissile material for multiple nuclear weapons is decreasing.” US and Iran clash over Russia using Iran drones in Ukraine 2022-12-19T05:00:00Z Obtaining fissile material is considered the greatest obstacle to making a nuclear weapon but there are others, notably the technical challenge of designing a bomb. Analysis: U.S. leaves door open for Iran nuclear diplomacy 2022-12-19T05:00:00Z The report calls foul on suggestions that China is not seeking to use its nuclear energy production infrastructure to produce fissile materials for those weapons. Pentagon warns of China’s plans for dominance in Taiwan and beyond 2022-11-29T05:00:00Z As of 2021, North Korea had enough fissile material for 40 to 50 nuclear warheads and could produce enough for six or seven bombs a year, according to an estimate by the Arms Control Association. North Korea’s Arsenal Has Grown Rapidly. Here’s What’s in It. 2021-03-26T04:00:00Z Material that can sustain a nuclear fission chain reaction is said to be fissile or fissionable. Chemistry 2019-02-14T00:00:00Z This isotope is fissile, making it more efficient for nuclear fuel. Why the US can’t quit Russian uranium 2022-08-09T04:00:00Z The U.N. experts said in the new report: “DPRK continued to develop its capability for the production of nuclear fissile materials at the Yongbyon site.” UN experts: North Korea is paving the way for new nuke tests 2022-08-04T04:00:00Z “Despite China’s public support for a fissile material cutoff treaty, we judge that Beijing intends to use this infrastructure to produce nuclear warhead materials for its military in the near term,” the report states. Pentagon warns of China’s plans for dominance in Taiwan and beyond 2022-11-29T05:00:00Z U.S. intelligence now estimates it could have enough fissile material for a nuclear weapon within weeks, compared to a year when the agreement was in force. Iran nuclear talks resume in last-ditch effort to secure deal 2022-08-03T04:00:00Z Naturally occurring uranium contains only 0.72% of 235U, the kind of uranium that is “fissile,” that is, capable of sustaining a nuclear fission chain reaction. Chemistry 2019-02-14T00:00:00Z When Trump spoke those words, Iran’s “breakout time” — the period it would need to accumulate enough fissile material for a nuclear weapon — was about a year. Opinion | Trump allowed Iran to go nuclear, but Biden will get the blame 2022-07-13T04:00:00Z That’s enough fissile material for a weapon, if it chose to pursue one. EXPLAINER: Why Iran cracks down at home, cozies up to Moscow 2022-07-13T04:00:00Z Rocks that are fissile, meaning they separate into thin sheets, are called shale. An Introduction to Geology 2017-01-01T00:00:00Z Since then, Tehran has blown past the agreed restrictions and now possess enough fissile material to make at least one bomb, if it decides to do so, according to nuclear weapons experts. Iran to send hundreds of drones to Russia for use in Ukraine, U.S. says 2022-07-11T04:00:00Z Nonproliferation experts warn that’s enough fissile material for one nuclear weapon if Iran chose to pursue it. Iran enriches to 20% with new centrifuges at fortified site 2022-07-10T04:00:00Z Breakout time is how long it would take Iran to acquire the fissile material for one bomb if it decided to. Analysis: Subtle shift in U.S. rhetoric suggests new Iran approach 2022-05-24T04:00:00Z Washington believes Iran is within weeks of obtaining fissile material for one nuclear weapon if it chose. Analysis: Iran nuclear deal near death, but West not ready to pull plug 2022-05-02T04:00:00Z Since 2019, Tehran has breached the deal’s nuclear limits and gone well beyond, rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran hopes for understanding with IAEA to resolve nuclear issues 2022-03-05T05:00:00Z The agreement between Iran and world powers was designed to make it harder for Iran to accumulate the fissile material for a bomb, an ambition it has long denied. Iran nuclear talks appear near climax, but no deal yet 2022-03-03T05:00:00Z Since 2019, Tehran has gone well beyond the deal's limits, rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran's Raisi calls on international community to reject US sanctions 2022-02-22T05:00:00Z Since 2019, Tehran has gradually breached the old deal's limits and gone well beyond, rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran not seeking nuclear weapons, needs atomic energy, says Khamenei 2022-02-17T05:00:00Z The Islamic Republic has since rebuilt stockpiles of enriched uranium, refining it to higher fissile purity, close to weapons-grade, and installed advanced centrifuges to speed up enrichment. Decision on Iran nuclear deal days away, ball in Tehran's court - France 2022-02-16T05:00:00Z The Iranians are now using sophisticated centrifuges and enriching up to 60 percent, just below the level where it is possible to have enough fissile material for a weapon. West warns time is growing short for Iran nuclear deal, as talks pause again 2022-01-31T05:00:00Z This is especially true if your fission system relies on highly enriched uranium—that is, uranium composed of 20 percent or more of the fissile isotope uranium 235. NASA’s ‘Nuclear Option’ May Be Crucial for Getting Humans to Mars 2022-01-27T05:00:00Z A year later, Iran began to gradually breach the accord, rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. China reaffirms opposition to U.S. sanctions on Iran 2022-01-15T05:00:00Z After waiting for a year, Iran responded to Trump's pressure by gradually breaching the accord, including rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran, US lock horns over sanctions relief, nuclear curbs in Vienna talks 2022-01-12T05:00:00Z The 2015 deal extended the time Iran would need to obtain enough fissile material for a nuclear bomb - if it chose to - to at least a year from about two to three months. Iranian and Russian officials strike positive tone on nuclear talks 2021-12-28T05:00:00Z A fourth PMD investigation involves undeclared fissile material and other activity at a site the sources didn’t identify. Opinion | The right Plan B for the moribund Iran nuclear deal 2021-12-16T05:00:00Z In September, the Institute for Science and International Security reported that, under what it described as the "worst-case breakout estimate," within a month Iran could produce enough fissile material for a nuclear weapon. Does Israel want war? It's determined to sabotage a new nuclear deal with Iran 2021-12-14T05:00:00Z He said the policy may actually have accelerated Iranian nuclear progress and that Iran now has the capability of producing enough fissile material for a nuclear bomb on four weeks’ notice. Israel opposed the Iran nuclear deal, but former Israeli officials increasingly say U.S. pullout was a mistake 2021-12-08T05:00:00Z Burns cautioned that, even if Iran decided to go ahead, it would still require a lot of work to weaponize that fissile material before attaching a nuclear weapon to a missile or other delivery system. Exclusive: As diplomacy stutters, U.S., Israel to discuss military drills for Iran scenario 2021-12-09T05:00:00Z That is close to what is required to produce bombmaking fissile material. New round of talks on Iran nuclear deal amid growing pessimism 2021-11-24T05:00:00Z "The Iranians today are closer to creating fissile material for nuclear weapons than they ever were in the past," the Israeli security official says. Iran nuclear programme: Threat of Israeli strike grows 2021-11-22T05:00:00Z Tehran responded by breaching key limits on nuclear activity set by the accord, including rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran says IAEA's Grossi to visit Tehran 'probably soon' 2021-11-15T05:00:00Z In reaction to Trump's reimposition of sanctions, Tehran breached the deal by rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran warns nuclear talks would fail unless Biden provides guarantees 2021-11-03T04:00:00Z U.S. officials have also long worried about America's ability to detect and destroy dispersed components of Iran's nuclear weaponization program once enough fissile material for a bomb were produced. Exclusive: As diplomacy stutters, U.S., Israel to discuss military drills for Iran scenario 2021-12-09T05:00:00Z Concerned about Iran now enriching uranium close to bomb-grade level of fissile purity, Western powers have repeatedly urged Tehran to resume talks, saying the diplomatic window would not stay open forever. Iran says Biden can issue 'executive order' if serious about returning to nuclear pact 2021-10-31T04:00:00Z In response to Trump's pressure, Tehran has gradually breached the deal by rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Iran says nuclear talks with six powers to resume by end November 2021-10-28T04:00:00Z Enriching uranium can provide a path to obtain the fissile material for an atomic bomb, an ambition Iran denies. U.S. envoy says Iran nuclear deal effort is at 'critical phase' 2021-10-25T04:00:00Z Although Iran has consistently denied it intends to build a nuclear weapon, the United States said at the time that it was only months away from accumulating enough fissile material for a bomb. U.S. and Iran enter ‘decisive’ period to revive nuclear accord or risk failure, U.N. watchdog chief says 2021-10-20T04:00:00Z Uranium enrichment is one way to obtain fissile material for a nuclear bomb, an ambition Iran denies. Iran not ready to resume Vienna talks, plans Brussels meeting first 2021-10-15T04:00:00Z In September, the International Atomic Energy Agency said Iran’s stockpile of uranium enriched to up to 20 percent fissile purity was estimated at 185 pounds, up from 138 pounds three months earlier. World Digest: Oct. 10, 2021 2021-10-10T04:00:00Z In response, Tehran breached the deal by rebuilding stockpiles of enriched uranium, refining it to higher fissile purity and installing advanced centrifuges to speed up output. Analysis-Quest for more leverage drives Iran's nuclear stalling tactic, analysts say 2021-10-05T04:00:00Z Under the deal, Iran agreed to place limits on its uranium enrichment program, which is one possible pathway to develop the fissile material for a nuclear weapon, in exchange for the easing of U.S., Exclusive-U.S. has reached out to China about cutting oil imports from Iran, officials say 2021-09-28T04:00:00Z A top issue creating a rift among Democrats — and an opportunity for lobbyists — is the debate over how much to spend and how hard to push utilities to end the use of fissile fuels. Democrats hit with ‘historic’ lobbying frenzy over $3.5 trillion social-welfare spending bill 2021-09-03T04:00:00Z The North’s production of fissile materials violates multiple resolutions from the United Nations Security Council, which has sought to stop the country from developing nuclear warheads, with little success. North Korea Restarted Plutonium-Producing Reactor, U.N. Agency Warns 2021-08-30T04:00:00Z Administration officials acknowledged that Iran’s potential “breakout” — the time needed to amass enough fissile material for a single nuclear weapon — is now down to a matter of months or less. Israeli PM to make case to Biden against Iran nuclear pact 2021-08-25T04:00:00Z The official said Iran's moves to produce uranium enriched to 60% fissile purity and uranium metal to 20% "represent an increasing threat" to regional security and non-proliferation of weapons. Iran's nuclear activity is concerning, says Saudi official 2021-07-09T04:00:00Z Under the 2015 deal, Iran agreed to limit the amount of fissile material that it stockpiles and to keep its purity level below what is needed for nuclear weapons. Opinion | One Way Forward on Iran: A Nuclear-Weapons-Free Persian Gulf 2021-06-12T04:00:00Z Nam said it would be “natural” for North Korea to push to build more nuclear weapons and fissile material if a stalemate in nuclear diplomacy is prolonged. Kim vows to build N. Korea socialism amid US nuclear impasse 2021-05-27T04:00:00Z The U.S. objective is to extend Iran’s “breakout” time — the time Tehran would require to produce enough fissile material for a nuclear weapon, should it choose to do so — thereby extending the U.S. “decision time.” Opinion | Blinken’s admirable penchant for the long view 2021-05-04T04:00:00Z In January, Iran began enriching uranium from the 3.67 concentration allowed under the deal to 20 percent — a step closer to the 90 percent required for the fissile material in a nuclear weapon. Iran begins uranium enrichment at highest level yet as Vienna nuclear talks continue 2021-04-16T04:00:00Z Iran’s deal with six powers caps the fissile purity to which Tehran can refine uranium at 3.67%. European powers warn Iran over 'dangerous' uranium enrichment move 2021-04-14T04:00:00Z That deal made it harder for Iran to amass the fissile material needed for a nuclear bomb -- a goal it has long denied -- in return for sanctions relief. EU to sanction Iran militia, police, three entities over 2019 protests, diplomats say 2021-03-31T04:00:00Z That deal made it harder for Iran to amass the fissile material needed for a nuclear bomb - a goal it has long denied - in return for sanctions relief. Exclusive: EU set to sanction more Iranians for rights abuses, first since 2013, diplomats say 2021-03-30T04:00:00Z The report by independent sanctions monitors said Pyongyang “produced fissile material, maintained nuclear facilities and upgraded its ballistic missile infrastructure” while continuing to seek material and technology for those programs from abroad. Exclusive: North Korea unresponsive to behind-the-scenes Biden administration outreach - U.S. official 2021-03-13T05:00:00Z The 2015 deal sought to extend Iran's “breakout time”—its capability to produce bombs from enriched fissile material—from a few months to at least a year. Biden Must Take Immediate Action to Reduce the Risk of Nuclear War 2021-03-02T05:00:00Z Refining uranium to high levels of fissile purity is a potential pathway to nuclear bombs, though Iran has long said it its enrichment programme is for peaceful energy purposes only. U.S. says ready for talks with Iran over nuclear deal 2021-02-18T05:00:00Z The 2015 deal’s central aim was to extend the time Iran would need to produce enough fissile material for a nuclear bomb to at least a year from roughly 2-3 months. Iran produces uranium metal, IAEA says, in latest breach of deal 2021-02-10T05:00:00Z The report by independent sanctions monitors said Pyongyang “produced fissile material, maintained nuclear facilities and upgraded its ballistic missile infrastructure” and continued to seek material and technology for those programs from abroad. North Korea developed nuclear, missile programs in 2020: U.N. report 2021-02-08T05:00:00Z However, the 20 percent enrichment level is also a relatively short, technical step from the 90 percent needed for the fissile material in a nuclear weapon. After anniversary of Soleimani’s killing, U.S.-Iran tensions run high 2021-01-04T05:00:00Z The JCPOA, proponents say, lengthened the time Iran would need to accumulate enough fissile material for a bomb, from several weeks to at least 1 year. Iran vows to build two new nuclear facilities, alarming observers 2020-12-08T05:00:00Z If Iran accumulated sufficient fissile material, it would need to assemble a bomb and probably one small enough to be carried by its ballistic missiles. Explainer: How close is Iran to producing a nuclear bomb? 2020-11-28T05:00:00Z Given the fissile nature of this moment, political violence is always lurking, and occasionally pounces. Counted out: Trump's desperate fight to stop the minority vote 2020-11-17T05:00:00Z Intelligence from the briefing challenges widely reported studies on Chinese fissile material production. EXCLUSIVE: China’s ‘secretive, crash’ nuclear buildup revealed 2020-11-12T05:00:00Z The 2015 deal was designed to extend the time Iran would need to produce enough fissile material for a nuclear bomb if it chose to do so to at least a year from 2-3 months. Iran finishes moving first batch of advanced centrifuges underground 2020-11-11T05:00:00Z Both reactors would also depart from conventional designs in using a fuel that is more highly enriched in uranium-235, the fissile isotope that is key to generating a chain reaction. Department of Energy picks two advance nuclear reactors for demonstration projects 2020-10-16T04:00:00Z “North Korea is more dangerous. It has more nuclear warheads, or fissile materials with which to produce nuclear weapons,” Chun said. As Kim wooed Trump with ‘love letters,’ he kept building his nuclear capability, intelligence shows 2020-09-30T04:00:00Z The problem was that it was so fissile that a gun design wouldn’t work — the material would pre-detonate before the pieces came together, creating a dud. Column: 75 years ago today, the Trinity A-Bomb test ushered in the era of nuclear warfare 2020-07-16T04:00:00Z During the talks, Washington asked North Korea to start dismantling its nuclear weapons and fissile materials before sanctions would be eased, but North Korea insisted they be lifted earlier. North Korea Vows to Boost Nuclear Program, Saying U.S. Diplomacy Failed 2020-06-11T04:00:00Z It is still, however, below the level required to create fissile material for a nuclear weapon. Iran blocking sites access - UN nuclear watchdog 2020-06-05T04:00:00Z The growing stockpile potentially gives Tehran a crucial ingredient for a future bomb — fissile uranium. Archive of secret Iranian nuclear documents draws fresh scrutiny as Tehran stockpiles enriched uranium 2020-03-05T05:00:00Z That deal is aimed at keeping Tehran at least a year away from obtaining enough fissile material for an atom bomb if it sought one. Exclusive: U.N. nuclear watchdog plans alert on Iranian stonewalling - diplomats 2020-03-02T05:00:00Z Pyongyang has produced enough fissile material “perhaps for six to eight or more nuclear weapons” since Mr. Trump and Mr. Kim held their first summit in Singapore in 2018, he said. U.S. targets North Korea hacking as nuclear talks sputter 2020-03-01T05:00:00Z Pyongyang has produced enough fissile material “perhaps for six to eight or more nuclear weapons” since Mr. Trump and Mr. Kim held their first summit in Singapore in 2018, he estimated. U.S. targets North Korean hackers, money sources as talks sputter 2020-02-29T05:00:00Z The aim was partly to stretch the time Iran needed to stockpile enough fissile material for a bomb — known as ‘breakout time’ — to at least a year. How quickly can Iran make a nuclear bomb? 2020-02-04T05:00:00Z The biggest obstacle to building a nuclear weapon is obtaining enough fissile material — highly enriched uranium or plutonium — for the core of the bomb. Iran fuels centrifuges, resumes uranium enrichment at Fordow 2019-11-06T05:00:00Z Bolton had said North Korea should hand over its nuclear weapons and fissile material to the United States the way Libya did in early 2004 in exchange for normalized relations and relief from sanctions. North Korea launches missile into waters near Japan days before nuclear talks set to resume with U.S. 2019-10-01T04:00:00Z Those traces were, however, of uranium, the diplomats said - the same element Iran is enriching and one of only two fissile elements with which one can make the core of a nuclear bomb. Exclusive: IAEA found uranium traces at Iran 'atomic warehouse' -... 2019-09-08T04:00:00Z Under the agreement, Iran is allowed limited research and development on advanced centrifuges, which accelerate the production of fissile material that can be used to make a nuclear bomb. Iran now operating advanced centrifuges in breach of nuclear pact 2019-09-07T04:00:00Z Doing so, experts said, reduces the amount of time needed for Tehran to stockpile the fissile material needed to build a nuclear weapon — if authorities chose to do so. Iran breaks more nuclear deal commitments, raising concern that the agreement is on verge of collapsing 2019-09-07T04:00:00Z The installation of advanced centrifuges would shorten Iran's so-called "break-out time" - the time required for it to produce enough fissile material for a bomb. Iran to speed up nuclear cycle in new deal breach 2019-09-07T04:00:00Z “We are working on these new generation nuclear reactors that use thorium instead of uranium, and thorium is not natively fissile, or radioactive. So the odds of a catastrophe drop precipitously.” The Democratic candidates are divided on nuclear energy 2019-09-05T04:00:00Z In practice, this means moving the three main physical components of a weapon — the warhead, missile-delivery system and fissile material core — either assembled or closer to where they need to be, ready for launch. India–Pakistan nuclear escalation: where could it lead? 2019-08-28T04:00:00Z Russian scientists said on Aug. 11 that the accident occurred as they studied “small-scale sources of energy with the use of fissile materials.” After Radiation Sensors Blink Off, Russia’s Explanations Change 2019-08-20T04:00:00Z He did not say how much fissile material had been involved in the accident, or what role it may have played in the explosion. Russia indicates rocket engine exploded in test of mini nuclear reactor 2019-08-12T04:00:00Z Spokeswoman Maja Kocijancic said the bloc was extremely concerned after Iran announced that it was producing material with a fissile purity of 4.5%. EU urges Iran to reverse nuclear deal breach 2019-07-08T04:00:00Z This week, Iran said it reached and slightly exceeded that level, which refers to the percentage of a uranium isotope that is considered fissile material potentially suitable for use in a bomb. Iran poised to press ahead with uranium enrichment despite Trump warning 2019-07-03T04:00:00Z Uranium refined to a fissile purity of 3.67% is deemed suitable for electricity generation and is the maximum allowed by the deal. Iran to boost uranium enrichment level, breaching nuclear pact:... 2019-07-03T04:00:00Z The 300 kilogram limit of uranium enriched to 3.67% is suitable for use in power plants but falls far short of the more than 90% enriched uranium needed for fissile material in a nuclear bomb. Iran vows to ‘soon’ breach uranium stockpile limits, as European efforts fall short 2019-06-29T04:00:00Z This isotype is a fissile material, which is capable of sustaining a nuclear fission chain reaction. Iran holds back on threat to breach nuclear deal 2019-06-27T04:00:00Z Iran’s signal of preparedness to stockpile enriched uranium beyond the deal’s limit, and refine uranium to a fissile purity higher than deemed necessary for civilian uses, prompted U.S. U.S. Navy says mine fragments suggest Iran behind Gulf tanker attack 2019-06-19T04:00:00Z The biggest obstacle to producing nuclear weapons is obtaining enough fissile material - weapons-grade highly enriched uranium or plutonium - for the bomb’s core. Factbox: Iran's commitments under its nuclear deal 2019-05-08T04:00:00Z The Hanoi talks collapsed after Trump proposed a “big deal” in which sanctions on North Korea would be lifted if it handed over all its nuclear weapons and fissile material to the United States. Satellite images may show reprocessing activity at North Korea... 2019-04-16T04:00:00Z Bolton did not disclose in those interviews the pivotal U.S. expectation contained in the document that North Korea should transfer its nuclear weapons and fissile material to the United States. Exclusive: With a piece of paper, Trump called on Kim to hand over... 2019-03-29T04:00:00Z Such panels are routinely used by international conventions to provide assessments of complex scientific and societal issues, such as those relating to fissile materials, forests, natural disasters, biodiversity and climate change. Adopt a moratorium on heritable genome editing 2019-03-12T04:00:00Z “As talks remain stalemated, the North will keep running its nuclear program and produce more fissile materials for more nuclear warheads.” Will Kim Jong-un Return to Brinkmanship? Weak Economy Is Forcing His Hand 2019-03-06T05:00:00Z Nuclear expert Siegfried S. Hecker estimated in a Post op-ed that North Korea created enough fissile material last year for six more nuclear bombs. Opinion | Trump’s hubris and inexperience set up the failure in Hanoi 2019-02-28T05:00:00Z “It would underscore that it is an active facility that does increase North Korea’s fissile material stocks to increase its arsenal.” Satellite images may show reprocessing activity at North Korea... 2019-04-16T04:00:00Z Power reactors use a uranium fuel that contains just a few percent of the fissile isotope uranium-235 and is made to be used once and discarded. Department of Energy moves forward with controversial test reactor 2019-02-28T05:00:00Z Washington wants the “final, fully verifiable” dismantlement of all of North Korea’s weapons of mass destruction, their delivery systems, fissile materials and production facilities. What’s at Stake as Trump and Kim Jong-un Meet Again 2019-02-26T05:00:00Z Would he agree to the verifiable destruction initially of some of his nuclear warheads and fissile production facilities over a set period of time for even greater relaxation of sanctions? Opinion | Trump must listen to the North Korea experts, not his gut 2019-02-15T05:00:00Z “The essential next step is a fissile material production freeze.” Donald Trump’s summit with Kim Jong-un faces high expectations 2019-02-24T05:00:00Z Power reactors typically use a fuel with a small amount of the fissile isotope uranium-235. Smaller, safer, cheaper: One company aims to reinvent the nuclear reactor and save a warming planet 2019-02-21T05:00:00Z Even if complete denuclearization is not possible, negotiators should at least seek a permanent end to testing and the production of fissile material. Editorial Roundup: Excerpts from recent editorials 2019-01-23T05:00:00Z But Washington wants the North to commit first to a detailed road map for full and verifiable denuclearization, starting with the declaration of all its nuclear weapons and fissile materials. North Korea Is Expanding Missile Base With Eye Toward U.S., Experts Warn 2018-12-06T05:00:00Z North Korea has not conducted a nuclear test since September 2017, but American experts think the country continues to produce fissile material. Trump to Meet With Kim Jong-un, Despite North Korea’s Lapses, Bolton Says 2018-12-04T05:00:00Z Weapons experts, as well as Mr. Pompeo, say that North Korea, despite engaging in denuclearization talks, continues to produce the fissile material that fuels nuclear arms. In North Korea, Missile Bases Suggest a Great Deception 2018-11-12T05:00:00Z North Korea can produce enough fissile material for six to seven bombs annually, said Siegfried Hecker, a Stanford University nuclear scientist. Diplomacy Appears Stalled With North Korea, Despite Trump’s Declarations 2018-11-07T05:00:00Z We also know that in the event of no deal, Euratom would no longer own special fissile material in the UK, with ownership transferring to the operators. Brexit and the UK's nuclear industry 2018-10-04T04:00:00Z The report shows that, though the last nuclear security summit was two years ago, nations are continuing to work toward properly securing fissile material and vulnerable nuclear sites. Opinion | The nuclear threat is real — but at least many governments are taking it seriously 2018-09-21T04:00:00Z “He’s avoiding giving up anything meaningful — actual weapons, fissile material and missiles.” North Korea’s New Nuclear Promises Fall Short of U.S. Demands 2018-09-19T04:00:00Z American officials want to see concrete steps from the North, including submitting a full list of its nuclear weapons and facilities and fissile materials, and freezing of its nuclear activities. Kim Jong-un Will Visit South Korea, Leaders Announce 2018-09-18T04:00:00Z According to international experts, Yongbyon houses 5 megawatt reactors, centrifuges, fissile materials used to build bombs, such as uranium and plutonium, and other facilities and equipment. North Korea's Kim says to scrap missile sites, visit Seoul 2018-09-19T04:00:00Z But Washington has been insisting that North Korea first take more significant steps toward denuclearization, such as submitting a full inventory of its nuclear weapons and fissile materials, before being rewarded. South Korean Leader Urges ‘Bold Decisions’ on North’s Denuclearization 2018-09-11T04:00:00Z Mr. Kim has not offered to provide a full inventory of nuclear weapons and fissile materials, as Washington has demanded. Kim Jong-un Says He Wants Denuclearization in Trump’s Current Term 2018-09-06T04:00:00Z American officials, mindful of North Korea’s past failures to honor promises, are insisting that North Korea move quickly toward denuclearization by submitting an inventory of its nuclear weapons and fissile materials. North Korea’s New Nuclear Promises Fall Short of U.S. Demands 2018-09-19T04:00:00Z With recent satellite photos showing North Korean weapons factories continuing to operate, reportedly producing fissile materials to make nuclear weapons, skeptics argue that the nuclear talks are going nowhere despite Mr. Trump’s expansive claims. Kim Jong-un North Korea denuclearization an effort to secure legitimacy 2018-09-06T04:00:00Z The predictable result is that North Korea is proceeding with its production of fissile material and missiles while demanding that Mr. Trump deliver on his promises. Opinion | There may be a way to negotiate with North Korea. This isn’t it. 2018-08-27T04:00:00Z North Korea has not agreed to do so and, according to Mr. Pompeo, is still producing fissile material at plants. Why Is the U.S. Wary of a Declaration to End the Korean War? 2018-08-14T04:00:00Z Last month in Senate testimony, Mr. Pompeo acknowledged that North Korea’s plants “continue to produce fissile material,” the technical term for the fuel at the core of nuclear warheads. Once ‘No Longer a Nuclear Threat,’ North Korea Now in Standoff With U.S. 2018-08-10T04:00:00Z Last week Secretary of State Mike Pompeo told senators that North Korean factories "continue to produce fissile material" used in making nuclear weapons. North Korea 'working on new missiles' 2018-07-30T04:00:00Z Secretary of State Mike Pompeo acknowledged during Senate testimony last week that North Korean factories “continue to produce fissile material” used in making nuclear weapons. US spy agencies: North Korea is working on new missiles 2018-07-30T04:00:00Z In fact, Pompeo acknowledged this past week that the North is still producing fissile material for nuclear weapons. AP FACT CHECK: Trump’s hyped claims on economy, NKorea, vets 2018-07-28T04:00:00Z He acknowledged that Pyongyang is still producing fissile materials and that human rights abuses continue. Trump administration offers reassurances on Russia as lawmakers grill Pompeo 2018-07-25T04:00:00Z “Yes, they continue to produce fissile material,” he told the committee, using the term for nuclear material that can be used in a bomb. Pompeo Defends Trump With ‘Proof’ of Administration’s Actions vs. Russia 2018-07-25T04:00:00Z North Korea is still producing fissile material for nuclear bombs in spite of its pledge to denuclearize, according to US secretary of state Mike Pompeo. North Korea still producing fissile material despite pledge, Pompeo says 2018-07-25T04:00:00Z Because it is more fissile, less plutonium is required for a weapon. All you wanted to know about nuclear war but were too afraid to ask 2018-07-16T04:00:00Z “What if we believe North Korea has enough fissile material for thirty-five weapons and it only declares thirty?” Will North Korea Play Nuclear Hide-and-Seek with Trump? 2018-07-02T04:00:00Z Doubts over North Korea’s intentions have deepened amid reports that it is continuing to produce fissile material for weapons. US plans for dismantling NKorea nukes may face resistance. 2018-07-02T04:00:00Z President Trump extended the national emergency on Friday due to "the existence and risk of proliferation of weapons-usable fissile material on the Korean Peninsula and the actions and policies of the Government of North Korea". N Korea still poses major threat - Trump 2018-06-22T04:00:00Z Asked at a Senate committee hearing whether this was the case, Pompeo responded on Wednesday by saying: “Yes, that’s correct ... Yes, they continue to produce fissile material.” North Korea still producing fissile material despite pledge, Pompeo says 2018-07-25T04:00:00Z And it is difficult on two levels: making the fissile material and then constructing a device that will detonate it. All you wanted to know about nuclear war but were too afraid to ask 2018-07-16T04:00:00Z But it remains in possession of fissile material for a dozen to 60 nuclear bombs, independent experts say. AP FACT CHECK: Trump misrepresents North Korea’s actions 2018-06-17T04:00:00Z The tests would use a dummy warhead without any fissile material. Trump poised to get new low-yield nuclear weapons 2018-06-13T04:00:00Z That would include “a declaration of all their nuclear sites and fissile material, including enriched uranium,” Yun agreed. Trump celebrates Singapore accord with North Korea, but substance has yet to be revealed 2018-06-12T04:00:00Z In 2012, shortly after ascending to the leadership of his country, Kim Jong Un agreed to a moratorium on long-range missile launches, nuclear tests and production of fissile material. Singapore summit agreement recycles old deals, defers the hard work 2018-06-12T04:00:00Z Uranium and plutonium are used for nuclear weapons, but only specific atomic configurations, or isotopes, of those elements are fissile. All you wanted to know about nuclear war but were too afraid to ask 2018-07-16T04:00:00Z The amount of fissile nuclear material needed for a bomb may be about the “size of a baseball,” he said. U.S. ready for North Korea nuclear crisis if talks fail 2018-06-10T04:00:00Z Third, it is necessary to begin moving down the more difficult road of eliminating the production of fissile material for weapons use. Opinion | A Trump-Kim summit could bear fruit. But we need to be smart. 2018-06-08T04:00:00Z A much more difficult, but crucial, “get” would be a full “declaration and accounting of all North Korean nuclear sites and fissile material.” Reality check on optimism swirling around Trump-Kim summit 2018-06-07T04:00:00Z That could include stopping its production of high-enriched uranium as bomb fuel, allowing United Nations nuclear inspectors back in the country, providing documentation on fissile fuel production, or other steps. With rival camps in his inner circle, Trump's ideas on North Korea have evolved 2018-06-05T04:00:00Z Recent activity around Yongbyon, the facility where North Korea began its nuclear weapons program, indicated that the reactor was back online, potentially producing fissile material to build more weapons. North Korea nuclear weapons dismantlement would take years 2018-06-03T04:00:00Z The United States signed a pact with Russia in 2000 agreeing to dispose of a certain amount of the Cold War-era fissile material from both countries, a deal that was seen as an arms-control milestone. Billions of dollars later, Energy Department pulls plug on partly built nuclear fuel plant 2018-05-11T04:00:00Z North Korea, unlike Iran, already has a nuclear bomb - and enough fissile material for dozens of them, most estimates show. Analysis: Trump pulled in 2 directions on Iran, North Korea 2018-05-08T04:00:00Z It turned out that North Korea was building a separate uranium enrichment facility so it could continue to produce fissile material even without Yongbyon. North Korea promises to dismantle its nuclear test site in public view, South says 2018-04-29T04:00:00Z “Questions remain about whether Kim will agree to discuss other nuclear technology, fissile material and missiles. However, they imply a phased process with reciprocal concessions,” Mount said in an email. Kim Jong-un says he’ll give up nuclear weapons if U.S. promises not to attack North Korea 2018-04-29T04:00:00Z “This example illustrates why the United States needs to obtain a well-defined, verified commitment from North Korea not to proliferate nuclear weapons, fissile materials and nuclear and nuclear-related goods,” Albright said. Suspicious factory underscores challenge of verifying North Korea’s nuclear promises 2018-04-21T04:00:00Z It also did not suspend the production of fissile material to build additional warheads, or the production of the longer-range missiles, which are Washington’s primary concern. AP Analysis: Good and bad news in NKorea’s latest nuke offer 2018-04-21T04:00:00Z For their part, the North Koreans appeared to be involved in furtive activities, which – along with the missile launch – convinced US intelligence agencies that they were seeking to continue making fissile material for a bomb. Two minutes to midnight: did the US miss its chance to stop North Korea’s nuclear programme? 2018-03-30T04:00:00Z But Mr Bolton was praised for his work establishing the Proliferation Security Initiative, an international agreement to prohibit fissile material shipments. John Bolton: Bush-era war hawk makes comeback 2018-03-22T04:00:00Z The greatest danger regarding fissile material comes when a nuclear state like the Soviet Union collapses, and the fate of weapons and such material falls into uncertainty. Nuclear energy can make a carbon-free future a reality 2018-03-21T04:00:00Z “They thought they were getting the normalization of relations with the United States, which never happened, and we thought we were stopping their ability to stock fissile material.” White House sends mixed messages on talks with North Korea 2018-03-09T05:00:00Z The stakes are high for this multibillion-dollar sector: a cyberattack combined with a physical one could, in theory, lead to the release of radiation or the theft of fissile material. Hacking nuclear systems is the ultimate cyber threat. Are we prepared? 2018-01-23T05:00:00Z The Obama administration said it was better to deal with the other issues once Iran’s ability to amass fissile material needed for nuclear weapons were kept in check. U.S. imposes sanctions on Iranian entities key to ballistic missile production 2018-01-04T05:00:00Z Together, Bohr and Wheeler developed a model for the activation energy of nuclear fission that predicted which isotopes of uranium and plutonium would most easily be fissile. This Man Was Einstein and Bohr's Relationship Counselor 2017-11-13T05:00:00Z In one wing, Iran is spinning centrifuges to enrich uranium until it contains at most 3.67% of the fissile U-235 isotope, the agreed limit. United States blocks Iran from fusion megaproject 2017-10-31T04:00:00Z But he said there was a difference between having the ability to fire a single nuclear missile and the capability of producing large amounts of fissile material and developing an arsenal of such weapons. North Korea: CIA director says regime nearly capable of nuclear attack 2017-10-19T04:00:00Z But he said there’s a difference between having the ability to fire a single nuclear missile and the capability of producing large amounts of fissile material and developing an arsenal of such weapons. CIA head: NKorea months from perfecting nuclear capabilities 2017-10-19T04:00:00Z It used implosion to assemble the critical mass by compressing the sphere that was made of the fissile material. Opinion | One Very Big Reason Not to Scrap the Iranian Nuclear Deal 2017-10-02T04:00:00Z We spent thousands of hours negotiating to get it right, even though Iran’s break-out time to produce enough fissile material for a bomb was just a few months. Opinion | The Iran deal is working. Here’s how we know. 2017-09-29T04:00:00Z Its nuclear fissile material is enough for at least 12 nuclear weapons, possibly as many as 60, depending on their size. War in Korea? The scenarios are sobering 2017-09-25T04:00:00Z Its nuclear fissile material is enough for least 12 nuclear weapons, possibly as many as 60, depending on their size. Escalating tension has experts simulating a new Korean War, and the scenarios are sobering 2017-09-25T04:00:00Z But he is reportedly not backed by the Israeli defence and intelligence establishment, which believes Iran is abiding by the agreement and its strict limits on nuclear activities and stockpiles of fissile material. Trump and Netanyahu ready united assault against Iran nuclear deal 2017-09-18T04:00:00Z Like the Hiroshima bomb, its fissile material was highly enriched uranium. Opinion | One Very Big Reason Not to Scrap the Iranian Nuclear Deal 2017-10-02T04:00:00Z The obstacles are designed to delay intruders for long enough to be caught before they reach three barrels at the center of the bunker—stand-ins for containers of fissile material. U.S.-China mission rushes bomb-grade nuclear fuel out of Africa 2017-08-31T04:00:00Z A half-dozen weapons would suggest pure deterrence, said Heinonen, who estimates that North Korea now has enough fissile material for up to 40 weapons — about 10 using plutonium and 30 using uranium. Why It's Hard to Know How Many Nukes North Korea Has 2017-08-18T04:00:00Z A half-dozen weapons would suggest pure deterrence, said Heinonen, who estimates that North Korea now has enough fissile material for up to 40 weapons - about 10 using plutonium and 30 using uranium. Estimates of North Korea’s nuclear weapons hard to nail down 2017-08-18T04:00:00Z The world contains many, many tons of fissile material, some of which is not now, or was not in the past, in extremely secure circumstances. Nuclear Expert Considers Risks of Conflict with North Korea 2017-08-12T04:00:00Z A nuclear detonation occurs when the high explosive implodes the hollow sphere of fissile material next to it to start an uncontrolled chain reaction. North Korea has made a nuclear weapon small enough to fit on a missile. How worried should the world be? 2017-08-09T04:00:00Z Before that could happen, the 9/11 terror attacks occured and the U.S. government suddenly had a new paramount priority in the nuclear arena: securing weapons-grade fissile materials in the far corners of the globe. U.S.-China mission rushes bomb-grade nuclear fuel out of Africa 2017-08-31T04:00:00Z North Korea began producing fissile material for bombs in the 1990s and conducted its first nuclear test explosion in 2006. Trump, North Korea trade escalating threats of fire 2017-08-09T04:00:00Z It also proposes ending the Euratom Community's ownership of fissile material on UK territory. Brexit: Government sets out post-EU nuclear proposals - BBC News 2017-07-13T04:00:00Z The government's answer to this is that medical isotopes are not fissile nuclear material - that is, capable of reacting - so they are not subject to international nuclear safeguards. Why does it matter if the UK leaves Euratom? - BBC News 2017-07-12T04:00:00Z McMillan initially promised to train fissile material handlers to be more heedful of plutonium-handling perils, for example, and to bring the inventory and safety documents guiding their work up to date. Safety problems at a Los Alamos laboratory delay U.S. nuclear warhead testing and production 2017-06-30T04:00:00Z The North has enough fissile material for up to 20 nuclear weapons. Why North Korea is testing so many missiles 2017-06-15T04:00:00Z Stewart added: “North Korea continues efforts to expand its stockpile of weapons grade fissile material.” Pentagon prepares to test its homeland missile defense system amid rising concerns about North Korea 2017-05-30T04:00:00Z His father, a former merchant marine who had retrained as a nuclear engineer, came to Richland to work for a plant that supplied fissile material to the Manhattan Project. James Mattis, a Warrior in Washington 2017-05-22T04:00:00Z The problem air war planners would face is that North Korea is suspected of operating secret, underground sites where fissile material is stored and where warheads are researched, developed and assembled, nuclear analysts say. North Korea missiles can defeat U.S. defense systems 2017-05-03T04:00:00Z If the Thaad missile system successfully intercepts a nuclear warhead, what happens to the fissile material in that warhead? North Korea crisis: Why now, what happened, what next? - BBC News 2017-04-27T04:00:00Z In addition to its nuclear and missile tests this year North Korea is also believed to producing more fissile material for bombs. 'Paranoid' North Korea won't stop building nuclear weapons – US spy chief 2016-10-25T04:00:00Z In addition to its nuclear and missile tests this year, North Korea is also believed to producing more fissile material for bombs. US intel chief: Getting NKorea to give up nukes 'lost cause' 2016-10-25T04:00:00Z The point of the agreement was to show the rest of the world that the drawdown would be permanent and to keep fissile material from falling into the wrong hands. Mr. Putin plays troublemaker on nuclear security 2016-10-23T04:00:00Z North Korea has made significant advances in producing fissile material — weapons-grade plutonium and enriched uranium. North Korea missiles can defeat U.S. defense systems 2017-05-03T04:00:00Z After the dissolution of the USSR, Russians and Americans worked together to secure and dispose of loose fissile material and warheads. Five myths about nuclear weapons 2016-09-30T04:00:00Z Unaccounted fissile material sloshing around the world can, with admitted difficulty, be fashioned into weapons. The Gathering Nuclear Storm 2016-09-23T04:00:00Z Yun also voiced concern that the North was accelerating its accumulation of fissile material with a view to mass producing nuclear bombs. SKorea questions ‘serial offender’ NKorea’s UN membership 2016-09-20T04:00:00Z He continues that we can't "rule out that a financially desperate leadership may risk the sale of fissile materials or other nuclear assets, perhaps to non-state actors". The alarming progress of a nuclear North Korea - BBC News 2016-09-13T04:00:00Z “North Korea’s numbers of weapons, based on fissile material estimates, are relatively large and growing,” Mr. Albright said. North Korea missiles can defeat U.S. defense systems 2017-05-03T04:00:00Z Though only a fraction of its 110 pounds of fissile material actually underwent fission, its force nevertheless was equal to about 16,000 tons of conventional explosives. Obama lands near Hiroshima, where he'll be first U.S. president to visit site of nuclear bombing 2016-05-27T04:00:00Z Pakistan has the fastest growing arsenal, producing fissile material for 10 to 15 additional weapons per year. Never Forget the Horror of Nuclear War 2016-05-25T04:00:00Z Little Boy was a uranium bomb packed with about 110 pounds of fissile material. What you need to know about the atomic bombing of Hiroshima 2016-05-24T04:00:00Z Other impediments include a Senate that refuses to ratify the Comprehensive Test Ban Treaty, and Pakistan, which has blocked negotiations on a treaty to halt production of fissile material. Editorial Roundup: Excerpts from recent editorials 2016-05-11T04:00:00Z In the interview, Mr. Moniz said he saw the U.S. government making only one purchase of the heavy water, which can be used to stimulate fissile reactions inside nuclear reactors. U.S. to Buy Material Used in Iran Nuclear Program 2016-04-22T04:00:00Z They could build a so-called “dirty bomb” around the fissile material that atomic arms require, and spew radiation across a city. Trump Wants to Free the Nuclear Genie 2016-03-30T04:00:00Z Instead of being two to three months from acquiring enough fissile material to build a nuclear weapon, Obama said, it is now a year away. Obama: Iran nuclear deal, prisoner release show the power of diplomacy 2016-01-17T05:00:00Z The nuclear pact calls on Iran to dismantle key nuclear equipment in a deal designed to ensure that Iranian officials could never accumulate enough fissile material to build a nuclear bomb. Plane leaves Iran with Post reporter, other Americans in swap 2016-01-16T05:00:00Z Inspectors from the IAEA, the global nuclear watchdog, will continuously monitor Iran's declared nuclear sites and also verify that no fissile material is moved covertly to a secret location to build a bomb. Iran nuclear deal: Key details - BBC News 2016-01-16T05:00:00Z “Determining what kind of fissile material and other isotopes were used for the bomb is another indicator.” Experts doubt North Korea's bomb was hydrogen-powered 2016-01-06T05:00:00Z They spent three decades as part of a peaceful, democratic majority entirely dominated by the fissile futility of a few hundred people’s atavism and arrogance. The scurrilous lies written about Charlie Hebdo | Robert McLiam Wilson 2016-01-02T05:00:00Z Low-enriched uranium is suited to power generation but can be further enriched to yield fissile material for nuclear warheads. Iran ships 25,000lb of low-enriched uranium to Russia as part of nuclear deal 2015-12-28T05:00:00Z Every now and then, tourists are allowed into Building 9204-3 to walk among the calutron machines that magnetically separated fissile uranium from the stable isotope of the metal. Goal of the Manhattan Project historical park is to 'remember and learn from' nation's nuclear achievements 2015-11-16T05:00:00Z One possible application of this technology is the enrichment of uranium to produce the high-grade fissile material necessary for nuclear reactors and weapons. Free Omid Kokabee, another Iranian prisoner of conscience 2015-10-30T04:00:00Z Analysts believe the first two tests used plutonium as the fissile material. How advanced is North Korea's nuclear programme? - BBC News 2015-09-15T04:00:00Z On Thursday, senators came to the chamber floor to defend or excoriate the deal, evoking everything from Nazis to fissile material to the Syrian refugee crisis. Democrats Hand Victory to Obama on Iran Nuclear Deal 2015-09-10T04:00:00Z "There is no way in 24 days, or 24 months, or 24 years for that matter," Kerry declared, "to destroy all the evidence of illegal activity that has been taking place regarding fissile material." The Iran Issue Isn't Going Away 2015-09-08T04:00:00Z The IAEA’s quarterly survey on Iran’s nuclear program also said Iran continued implementing the bulk of its commitments to scale back its stockpile of fissile material and freeze parts of its nuclear program. New Construction Activity Reported at Controversial Iranian Facility 2015-08-27T04:00:00Z Several Pakistani analysts questioned the findings of the new report, saying it’s based on a faulty assumption that Pakistan is using all of its existing stockpiles of fissile material to make nuclear weapons. Report: Pakistan's nuclear arsenal could become the world’s third-biggest 2015-08-26T04:00:00Z The agreement calls for Iran to reduce its stockpiles of fissile material, put most of its uranium-enriching centrifuges into storage and allow international inspectors to monitor compliance. Another Democratic senator says he will vote against Iran nuclear deal 2015-08-18T04:00:00Z Then, Obama said the United States would “seek a new treaty that verifiably ends the production of fissile materials intended for use in state nuclear weapons.” Obama will echo Kennedy’s American University nuclear speech from 1963 2015-08-04T04:00:00Z “They have mastered the ability to produce significant amounts of fissile material. You can’t bomb away that knowledge any more than you can sanction it away.” John Kerry warns Congress: back Iran nuclear deal or face dire consequences 2015-07-28T04:00:00Z Specifically, the deal blocks each of Iran’s possible pathways to producing fissile material for a nuclear weapon: the highly enriched uranium and the plutonium production pathways, as well as the covert pathway. John Kerry and Ernest Moniz: The case for the nuclear deal with Iran 2015-07-21T04:00:00Z The U.S deployed all of this nuclear weapons know-how—especially the national labs and their mastery of "separative work units" needed to enrich fissile material—to craft a nuclear deal with Iran. 70 Years Since the First A-Bomb, Humanity Still Lives in Its Afterglow 2015-07-16T04:00:00Z The Union of Concerned Scientists noted some weaknesses in the agreement but said that if fully implemented, it “will significantly restrict Iran’s ability to produce fissile materials suitable for nuclear weapons for the next decade.” Editorials from around Pennsylvania 2015-07-15T04:00:00Z The overall scope of the deal seeks to put Iran at least one year away from nuclear weapons “breakout” levels — the time it would take to produce enough fissile material for one nuclear bomb. Historic deal reached with Iran to limit nuclear program 2015-07-14T04:00:00Z The deal focuses on limiting Iran's ability to produce and maintain the fissile material needed to build nuclear weapons. The historic nuclear deal with Iran: How it works 2015-07-14T04:00:00Z Low-enriched uranium can be further enriched to make fissile material for an atomic bomb, and one of the main goals of any nuclear deal is to restrain Iran's production of it. U.S. and Iran: the unbearable awkwardness of defending your enemy 2015-07-05T04:00:00Z They do not want a situation in which Iranian capacity suddenly expands exponentially from year 11 onwards, giving it the capability to make fissile material very rapidly. Negotiators at Iran nuclear talks give themselves another week 2015-06-30T04:00:00Z Iran says that program is only for peaceful purposes, but enriched uranium can also form the fissile core of a nuclear warhead. For world, limited options if Iran talks fall apart 2015-06-29T04:00:00Z Enriched uranium can be used as fuel for nuclear power plants and, at much higher concentrations, as fissile material for nuclear weapons. Iran sets strict conditions for nuclear deal 2015-06-24T04:00:00Z We never expected the Iranians to create the fissile material for a weapon at Natanz, their declared facility. MICHAEL HAYDEN: John Kerry’s unreliable words undermine Iran talks 2015-06-17T04:00:00Z But it wouldn't be enough time to hide evidence of the uranium enrichment facilities Iran would need to create the fissile material required for a bomb. In Iran nuclear talks, discord on inspecting undeclared facilities 2015-06-09T04:00:00Z Centrifuges purify uranium gas fed into them for use as fuel in nuclear reactors or weapons, if purified to levels of around 90 percent of the fissile isotope uranium-235. Exclusive: Czechs stopped potential nuclear tech purchase by Iran - sources 2015-05-13T04:00:00Z If Iran opts to return to enriching at levels just a technical step away from weapons-grade, it could have enough fissile material for one bomb within months. For world, limited options if Iran talks fall apart 2015-06-29T04:00:00Z In fact, to prevent Iran from obtaining nuclear weapons capability, the U.S. must impose the most stringent possible limits on Iran’s ability to produce fissile material. Obama’s Iran Nuclear Deal Is an Unforgivable Betrayal of Israel 2015-04-17T04:00:00Z It will take Iran some time to take steps such as shutting down and disconnecting some of its centrifuges, which can produce fissile material for an atomic bomb. U.S. Iran bill makes nuclear deal harder, but not impossible 2015-04-15T04:00:00Z The fourth pathway would be to produce enough fissile material for a weapon through covert means. A strong step toward a safer Iran 2015-04-12T04:00:00Z On the crucial issues to do with curbing Iran’s ability to produce fissile material for bomb-making, the differences are more spin than substance. Too soon to celebrate 2015-04-09T04:00:00Z No fissile material would be located at the site. With Details of Iran Deal Still in Flux, White House Opens Sales Effort 2015-04-07T04:00:00Z The Senate Foreign Relations Committee understands that breakout time is crucially related to the size of Iran’s stockpile of fissile material. Obama’s Iran Nuclear Deal Is an Unforgivable Betrayal of Israel 2015-04-17T04:00:00Z What becomes of all the fissile material Iran has apparently agreed to export? Iran’s remarkable achievement 2015-04-03T04:00:00Z When the Iranians insisted on keeping some centrifuges at Fordo, Mr. Obama approved the concession after Mr. Moniz assured him the facility, devoid of fissile material under the accord, would pose no threat. An Iran Nuclear Deal Built on Coffee, All-Nighters and Compromise 2015-04-03T04:00:00Z Two facilities will be converted into research sites without fissile material. The Iran Nuclear Deal: What You Need to Know 2015-04-03T04:00:00Z For example, it leaves Iran two to three months from having enough fissile material to make a bomb. Nuclear Agreement With Imperial Iran Is Something, But Not Enough 2015-04-03T04:00:00Z The agreement is based on a theoretical benchmark: that Iran would need at least a year to produce fissile material sufficient for a weapon, compared with two months or less now. Obama’s Iran deal falls far short of his own goals 2015-04-02T04:00:00Z Many expected the total amount of fissile material Iran is allowed to keep to be higher than the agreed 300 kilograms. Iran’s remarkable achievement 2015-04-03T04:00:00Z That level of low-enriched uranium is suitable as fuel for nuclear power plants but not as fissile material for nuclear weapons, which require uranium enriched to about 90 percent purity. Iran agrees to nuclear restrictions in framework deal with world powers 2015-04-02T04:00:00Z Mr. Corker said that he believed sanctions would be lifted too quickly, and that he wanted to better understand what would happen to Iran’s fissile nuclear materials. Congress Responds Cautiously to Framework, and Demands Right to Review Deal 2015-04-02T04:00:00Z As a result, the so-called breakout time—the time required to acquire fissile material sufficient for one bomb—will be extended to a year; it is currently only two or three months. Iran: It’s a Deal, Almost 2015-04-02T04:00:00Z It also agrees to ship all spent fuel — which contains some fissile material — for the reactor's lifetime. A glance at commitments under preliminary Iran nuke deal 2015-04-02T04:00:00Z Progress has been made on the main issue — the future shape of Iran's uranium enrichment program, which can produce material for energy, science and medicine but also for the fissile core of a nuclear weapon. Iran nuke talks expand as deadline for deal looms 2015-03-28T04:00:00Z That would give them clues to whether Iran was trying to siphon off fissile materials to be used covertly in weapons production. Iran’s foreign minister says no nuclear pact this week 2015-03-18T04:00:00Z The overall goal is to limit Iran's production and stockpiling of enriched uranium so that the country would need 12 months to produce enough fissile material to fuel one bomb. Seven key questions about the Iran nuclear negotiations 2015-03-18T04:00:00Z The United States is aiming to have a one-year “breakout” period, defined as the time Iran would need to produce the fissile material for one nuclear bomb. Talks on Iran’s nuclear future resume, with focus on technical matters 2015-03-17T04:00:00Z It also commits Tehran not to do uranium enrichment-related research and development or store fissile material at Fordo for 15 years. A glance at commitments under preliminary Iran nuke deal 2015-04-02T04:00:00Z The machines can enrich uranium up to levels used for the fissile core of nuclear arms, but Iran says it only has energy, medical and scientific aims. Iranians express optimism over nuclear agreement 2015-03-17T04:00:00Z Stocks of fissile materials held by countries outside the small club of nuclear-weapons states, he said, are just “not that important” a threat, compared with the thousands of nuclear weapons held by the bigger powers. U.S. frets over South African vault with enough fuel for 6 nuclear bombs 2015-03-13T04:00:00Z The Obama Administration may be on the verge of completing a deal that leaves Iran with a substantial nuclear capability, but about a year away from a bomb’s worth of fissile material. Obama’s Nuclear Deal Could Mean War 2015-03-12T04:00:00Z But the United States and its negotiating partners want to ensure that Iran does not have the capability of amassing enough fissile material to make a nuclear warhead. Talks on Iran’s nuclear future resume, with focus on technical matters 2015-03-17T04:00:00Z He agreed that the Iranians would ship their stockpiles of low-grade fissile material to Russia in exchange for fuel rods for energy. Obama Misleads the Public About Iran's Nuclear Program 2015-03-06T05:00:00Z The A.E.C. assumed that the financial value of the fissile material would encourage companies to safeguard it carefully. Nuns and Nuclear Security 2015-02-28T05:00:00Z Kerry said a vital component would be a rigorous international inspection regime to ensure Iran was not seeking nuclear weapons, saying the Islamic Republic already has the knowledge to make fissile material. Kerry cautions Israel not to undercut Iran diplomacy as talks resume 2015-03-02T05:00:00Z Negotiators are reportedly headed toward a deal in which Iran would keep around 6,000 relatively inefficient enrichment centrifuges, limit stockpiles of potentially fissile materials and submit all its nuclear facilities to rigorous inspection. A necessary deal with Iran 2015-02-26T05:00:00Z He said the deal apparently coming together with Iran would allow the country that has in the past threatened to destroy Israel to develop the means to create fissile material to produce many nuclear weapons. Kerry questions Netanyahu's judgment as U.S.-Israel row deepens 2015-02-25T05:00:00Z "Breakout is the amount of time it takes to develop enough fissile material for one weapon. ... You still gotta go design a means of delivery," he said. Kerry braces for Day 2 of quizzing on Capitol Hill 2015-02-25T05:00:00Z In 1972, the terrorist attack on the Munich Olympics prompted much tougher federal oversight of fissile materials. Nuns and Nuclear Security 2015-02-28T05:00:00Z According to The Wall Street Journal, now they have the knowledge, the components and the infrastructure to produce fissile material plus delivery systems and the know-how to master weaponization. Obama's Course to a Nuclear-Capable Iran 2015-02-06T05:00:00Z The two leaders said they agreed to advance a 2008 civil nuclear deal long stalled by concerns about India's reluctance to allow U.S. tracking of fissile material. India nuke deals still thorny for US despite 'breakthrough' 2015-01-27T05:00:00Z American policy is to track fissile material, even though India has not proliferated nuclear weapons or material. Obama’s visit spurs hope that obstacles to U.S.-India relations can be overcome 2015-01-23T05:00:00Z As a result, Iran today is further away from obtaining enough fissile material for a nuclear weapon than before the negotiations. Give diplomacy with Iran a chance 2015-01-21T05:00:00Z New storage facilities were built in Russia; modern security systems were introduced; fissile materials were removed from unguarded sites and locked away. Nuns and Nuclear Security 2015-02-28T05:00:00Z The monthly update by the International Atomic Energy Agency said Iran was not enriching uranium above a fissile concentration of 5 percent. Iran honors nuclear deal with powers, IAEA report shows 2014-12-19T05:00:00Z These days, we call that a problem: the remaining fissile material that must be protected from accidental discharge or proliferation and stored indefinitely. The Young Turks Who Are Reviving Nuclear Power Accordingly, Iran earlier this year eliminated its stockpile of uranium gas enriched to a fissile concentration of 20 percent, a relatively short technical step from weapons-grade material. Iran to turn uranium into reactor fuel under extended deal: source 2014-12-01T05:00:00Z But if processed to a high degree, 90 percent, the material could also provide the fissile core of a nuclear weapon, which the West fears may be its ultimate aim. Iran's uranium stockpile grows before deadline for nuclear deal 2014-11-08T05:00:00Z An insider at a nuclear facility might secretly remove a few ounces of fissile material every so often and accumulate a significant amount of it over time. Nuns and Nuclear Security 2015-02-28T05:00:00Z The powers are seeking to limit the size of Iran's future nuclear program and thereby extend the time it would need to accumulate fissile material for a weapon. U.N. nuclear chief suggests progress slow in Iran investigation 2014-10-20T04:00:00Z The challenge for the scientists racing to develop these terrifying new weapons was getting hold of enough fissile material. The element that causes arguments 2014-10-18T04:00:00Z Western powers suspect Iran's refusal to place strict limits on uranium enrichment capacity reflects an underlying agenda to preserve the option of accumulating enough fissile material to fuel nuclear bombs. Iran nuclear talks likely on fringes of U.N. General Assembly: IRNA 2014-08-05T04:00:00Z Western experts say Iran would now be able to amass enough high-enriched fissile material for one bomb in a few months, if it opted for such a weapon of mass destruction. Iran's uranium stockpile grows before deadline for nuclear deal 2014-11-08T05:00:00Z Russia has the most nuclear weapons and the largest amount of fissile material in the world. Nuns and Nuclear Security 2015-02-28T05:00:00Z The main dispute is over uranium enrichment, which can make both reactor fuel and the fissile core of nuclear warheads. Obama: Significant gaps on Iran nuclear talks 2014-07-16T04:00:00Z The uncontrolled nuclear reactions in atomic bombs require a high concentration of fissile material. The element that causes arguments 2014-10-18T04:00:00Z Deep divisions persist over uranium enrichment, which can produce both reactor fuel or fissile warhead cores. Foreign ministers to join troubled Iran nuke talks 2014-07-10T04:00:00Z India and Pakistan are also developing new systems capable of delivering nuclear weapons and are expanding their capacities to produce fissile material for military purposes. Nuclear powers modernising arsenals, says study 2014-06-16T04:00:00Z Meanwhile, at least twenty-five countries now possess two pounds or more of weapons-grade fissile material, and some nuclear sites overseas don’t even have armed guards. Nuns and Nuclear Security 2015-02-28T05:00:00Z Instead it should restrict itself to a few hundred of the machines used to increase the concentration of the fissile isotope. France says Iran talks 'hitting a wall'; July deadline in doubt 2014-06-10T04:00:00Z Plutonium nuclei are fissile and the first nuclear reactors around the world became factories to convert uranium into plutonium for bomb programmes. The element that causes arguments 2014-10-18T04:00:00Z Under the November 24 agreement, Iran agreed to halt its higher-grade uranium enrichment work and to dilute and convert its stockpile of uranium enriched to a fissile purity of 20 percent. Iran expects next payment under nuclear deal, confirming compliance 2014-04-16T10:33:00Z “This is the biggest commitment to remove fissile materials in the history of the summit process that President Obama launched,” Elizabeth Sherwood-Randall of the National Security Council told the Times. Japan to Turn Over Nuclear Cache to U.S. 2014-03-24T11:40:03Z Only a couple of fissile materials can readily be used to produce the extraordinary destructive force of a nuclear weapon. Nuns and Nuclear Security 2015-02-28T05:00:00Z Uranium forms the core of a nuclear bomb if enriched to a 90 percent fissile concentration. Iran seeks banned nuclear items, uses China trader for missile parts: U.S. 2014-03-17T17:35:43Z Obtaining weapons-grade fissile material - HEU or plutonium - poses the biggest challenge for militant groups, so it must be kept secure both at civilian and military sites, experts say. World leaders seek action to counter nuclear terrorism risk-draft 2014-03-17T12:40:23Z Uranium forms the core of a nuclear bomb if enriched to a high fissile purity. Iran pursuing banned items for nuclear, missile work: U.S. official 2014-03-16T15:47:36Z “In theory, Ukraine could develop an indigenous capability to produce fissile material,” Samore says. Don’t Worry, Ukraine Won’t Go Nuclear 2014-03-12T19:17:16Z Instead of dealing with all that hassle and expense, terrorists would be far more likely to steal fissile materials or buy them on the black market. Nuns and Nuclear Security 2015-02-28T05:00:00Z The goal of the talks for the United States and its European allies is to extend the time that Iran would need to produce enough fissile material for a nuclear weapon. Iran, powers hold 'substantive' nuclear talks; U.S., Iranians meet 2014-02-19T00:12:00Z The goal of the talks for the United States and its European allies is to extend the "breakout time" that Iran would need to produce enough fissile material for a bomb. Iran and U.S. agree final nuclear deal may be unreachable 2014-02-17T23:49:35Z While Iran a month ago stopped its most proliferation-sensitive work, enrichment to a fissile concentration of 20 percent, it is allowed under the half-year agreement to continue producing uranium refined to up to 5 percent. Iran seen honoring nuclear deal but stockpile may grow: diplomats 2014-02-17T17:35:50Z But nuclear experts say Iran must sharply reduce its centrifuges in order to extend the time for producing enough weapons-grade fissile material for a bomb. West aims to minimize nuclear bomb risk in Iran talks 2014-02-14T11:16:21Z Although the federal government owned the land and most of the buildings, the equipment, and the fissile material at the Y-12 complex, private contractors now ran the facility for profit. Nuns and Nuclear Security 2015-02-28T05:00:00Z Under the interim deal, Iran agreed to suspend enrichment of uranium to a fissile concentration of 20 percent, a short technical step away from the level needed for nuclear weapons. West, Iran activate landmark nuclear deal 2014-01-21T02:53:31Z At a time of hardship, austerity and government efforts to curb the once-munificent welfare state, the question of immigration draws on a fissile blend of economic fear, ethnic stereotyping and political maneuver. Letter From Europe: For Britain, Big Decisions on Identity 2014-01-02T12:08:37Z We have no intention of producing weapons or fissile material programs. Iran Foreign Minister: Sanctions Would Kill Nuke Deal 2013-12-09T14:35:20Z Refined uranium also provides the fissile core of an atomic bomb if refined to a high degree. U.S. has eyes 'wide open' to risks on Iran deal: Kerry 2013-11-24T16:19:43Z Refined uranium can be used to fuel nuclear power plants - Iran's stated goal - but also provide the fissile core of an atomic bomb if refined much further. Iran digs in heels on enrichment at nuclear talks 2013-11-24T00:02:29Z That is because enrichment to a fissile concentration of 20 percent - compared to the 3.5 percent usually required for nuclear power plants - represents most of the work needed to reach weapons-grade uranium of 90 percent. Iran nuclear deal may reduce, not eliminate, any bomb breakout risk 2013-11-21T12:40:51Z They include suspending enrichment of uranium to 20 percent fissile purity - a significant advance towards the threshold for bomb fuel - as well as limiting its enrichment capacity and mothballing the Arak reactor project. U.S. says 'very hard' to clinch deal as Iran nuclear talks resume 2013-11-21T08:36:17Z But it appears inevitable that Iran will be allowed to continue spinning some centrifuges, improving its ability to enrich uranium, the fissile material required for a bomb. Majority Leader Eric Cantor: President Obama Should Abandon This Terrible Deal with Iran 2013-11-20T20:41:38Z They include suspending enrichment of uranium to 20 percent fissile purity - a significant advance toward the threshold for bomb fuel - as well as limiting its enrichment capacity and mothballing the Arak reactor project. World powers, Iran make new attempt to clinch nuclear deal 2013-11-20T00:10:02Z MOX is nuclear fuel that contains more than one oxide of fissile material. Hinckley firm denies fuel claim 2013-11-06T14:45:24Z Iran's enrichment of uranium to a fissile level of 20 percent is a major technical step taking it just short of the concentration needed for a nuclear weapon. No confirmation Iran has halted higher-grade enrichment -diplomats 2013-10-25T18:52:04Z Western officials have repeatedly said that Iran must suspend enriching uranium to 20 percent fissile purity, their main worry, before sanctions are eased. U.S. says talks intense, serious after Iran hints at atomic concessions 2013-10-17T06:48:30Z At the core of the dispute are Iranian efforts to enrich uranium to 20 percent fissile purity, a technological advance that brings it close to producing weapons-grade fuel. Iran says 'too soon to judge' if progress made at Geneva nuclear talks 2013-10-15T18:00:03Z Iran chose U as the fissile material as it is easier to just enrich, rather than produce Pu and reprocess it to sufficient purity. Iran's Dangerous Nuclear Bluff 2013-10-13T08:27:00Z Nuclear power stations generally run on uranium enriched to 5 percent fissile purity, while the medical reactor requires 20 percent enriched fuel. 'Death to America' chants challenge Iran president's diplomacy 2013-10-11T14:36:24Z The 20-percent threshold is a core concern because that level of fissile purity marks an important technological step on the way to producing the fuel needed for a bomb. West unlikely to offer immediate sanctions relief in Iran talks 2013-10-08T17:13:22Z Uranium refined to 20 percent of fissile purity brings it technically close to the weapons-grade level of 90 percent. Israel bleak about U.S.-Iran rapprochement at U.N. summit 2013-09-24T18:50:25Z Nuclear weapons pose a greater risk, but as the Canadian researcher Robin Frost writes, even if terrorists got their hands on loose fissile material from the former Soviet Union, the technology might be literally inoperable. ‘Black budget’ leaked by Edward Snowden describes NSA team that hacks foreign targets 2013-08-30T19:00:00Z It was a white-knuckled effort at times, since local scavengers in search of scrap metal were regularly digging “within yards” of the fissile material. A Secret Race for Abandoned Nuclear Material 2013-08-17T17:21:13Z Concentrating fissile material in one place could result in a criticality event—a self-sustained nuclear chain reaction—the same principle behind an atomic bomb. The Plutonium Gang: CH2M Hill Dismantles the Hanford Nuclear Site 2013-08-01T19:26:01Z In conventional reactors, composition of the isotope uranium-235 has to be increased in the fuel before it becomes fissile. Nuclear Advocates Pin Hopes on Safer Reactor Designs 2013-08-05T10:50:26Z Obtaining weapons-grade fissile material - highly enriched uranium or plutonium - poses the biggest challenge for militant groups, so it must be kept secure both at civilian and military facilities, experts say. Governments warn about nuclear terrorism threat 2013-07-01T18:14:13Z Obtaining weapons-grade fissile material - highly enriched uranium or plutonium - poses the biggest challenge for militant groups, so keeping it secure is vital, both at civilian and military facilities, experts say. U.N. nuclear chief warns of 'dirty bomb' threat 2013-07-01T12:48:32Z Obtaining weapons-grade fissile material - highly enriched uranium or plutonium - poses their biggest challenge, so keeping it secure is vital, both at civilian and military facilities. Missing nuclear material may pose attack threat: IAEA 2013-06-28T09:47:09Z Analysts say radical groups could theoretically build a crude but deadly nuclear device if they have the money, technical know-how and the amount of fissile material needed. World worried about nuclear terrorism, but little action at talks 2013-06-24T14:27:29Z Obama also wants to see negotiations on a treaty to end the production of fissile materials for weapons. Obama challenges Russia to agree to deeper nuclear weapon cuts 2013-06-20T01:05:16Z He also wants to see negotiations on a treaty to end the production of fissile materials for weapons. Obama challenges Russia to agree to deeper nuclear weapon cuts 2013-06-19T17:47:57Z Pakistan has blocked the opening of negotiations on the fissile material ban, and administration officials say they will put pressure on the new Pakistani government to move on that issue. Obama Has Plans to Cut U.S. Nuclear Arsenal, if Russia Reciprocates 2013-06-19T01:27:32Z One confidence-building measure might be for Iran to explore medical isotope production that avoids using or producing fissile material. Finding Less Risky Ways to Make Medical Isotopes 2013-06-13T23:10:00Z Obtaining weapons-grade fissile material - highly enriched uranium or plutonium - poses their biggest challenge, so keeping it secure is vital, both at civilian and military facilities, experts and officials say. World worried about nuclear terrorism, but little action at talks 2013-06-24T14:27:29Z Tasked with preventing the spread of nuclear bombs in the world, the U.N.'s International Atomic Energy Agency inspects reactors and related sites globally to ensure that sensitive fissile material is not diverted for military purposes. Iran not U.N. nuclear watchdog's only headache, report shows 2013-06-07T12:52:03Z Analysts believe the first two tests used plutonium as the fissile material, but it is not known whether the third used plutonium or uranium. N Korea reactor ‘near completion’ 2013-06-04T08:07:36Z And nuclear experts believe any sign Japan is expanding its ability to produce weapons-usable fissile materials will likely be matched by Beijing. Japan's Nuclear Plan Unsettles U.S. 2013-05-02T02:59:29Z This could be done by, for instance, ceasing production of fissile material for nuclear weapons or refraining from conducting missile tests. Viewpoint: Are US-North Korea talks possible? 2013-04-30T23:50:42Z Iran, he said, must not amass enough uranium at 20 percent fissile purity to fuel one bomb if enriched further. Analysis: Israeli credibility on line over Iran nuclear challenge 2013-04-28T09:59:33Z This could also allow it to produce bomb-grade fissile material, a step Washington is loathe to see in part because of its nuclear standoffs with Iran and North Korea. U.S. tells North Korea new missile launch would be "huge mistake" 2013-04-13T03:48:59Z We can ask for no more production of nuclear weapons and fissile material, but whatever you have you can keep. Should the U.S. Take North Korea s Nuclear Threats Seriously? 2013-04-11T11:15:08.157Z At the core of the powers' concerns is Iran's enrichment of uranium to 20 percent fissile purity, a level that closes an important technological gap en route to making weapons-grade material. World powers await Iran's reaction to nuclear offer 2013-04-04T22:13:24Z Reactivating the aged Soviet-era reactor at the Yongbyon nuclear plant would yield plutonium, a tested path to stockpile more fissile material than a uranium enrichment program. North Korea to restart nuclear reactor in weapons bid 2013-04-03T00:14:19Z The first two tests used fissile material produced by the reactor at Yongbyon, which was shut down in 2007 as part of a diplomatic deal that sent heavy fuel oil to the North. U.S. struggling to contain nuclear threats from North Korea, Iran 2013-04-02T20:59:51Z The facility is used for enriching uranium to 20 percent fissile purity, a short technical step from weapons grade. Powers wait to hear Iran response to nuclear offer 2013-02-27T04:30:24Z Iran says it enriches uranium to a fissile concentration of 20 percent to make fuel for a medical research reactor in the capital Tehran. Powers to offer Iran sanctions relief at nuclear talks 2013-02-26T06:10:19Z The West says Iran's enrichment of uranium to a fissile purity of 20 percent demonstrates its intent to develop a nuclear weapons capability, an allegation the Islamic republic denies. Iran announces uranium finds, days before nuclear talks 2013-02-23T13:59:45Z This lack of scientific evidence suggests that key questions may remain unanswered about the type of fissile material used in the test, which was detected by seismic sensors. Spy agencies scrounge for details on North Korean nuclear test 2013-02-20T22:44:16Z Enriching uranium to a fissile concentration of 20 percent is especially worrisome for the West as it represents most of the work required to obtain weapons-grade material. U.N. report may show slower growth in Iran nuclear stockpile 2013-02-20T18:37:41Z The United States and its allies are particularly worried about Fordow because Iran is refining uranium there to a fissile concentration of 20 percent, which Iran says it needs for a medical reactor. Iran will never shut down Fordow enrichment plant: MP 2013-02-17T13:33:03Z It was Iran's first acknowledgment that it had apparently resumed converting into fuel small amounts of uranium enriched to a concentration of 20 percent fissile material. Iran says it is converting uranium, easing bomb fears 2013-02-13T03:18:16Z Iran said it would use the new model at a unit in Natanz, where it is now refining uranium to a fissile concentration of up to five percent, according to the IAEA's communication. Defiant Iran plans to speed up nuclear fuel work 2013-02-01T01:20:21Z Saying the information was like a nuclear weapon, the group said it had "enough fissile material for multiple warheads" which it would launch against the justice department and organisations linked to it. Anonymous takes down US Sentencing Commission website 2013-01-26T16:48:00Z The North Korean nuclear crisis began in the early 1990s with nothing but a tiny amount of fissile material North Korea was suspected of gleaning from its experimental research reactor. North Korea Turns Its Ire on South Korea 2013-01-25T07:54:29Z Iran is refining uranium to a fissile concentration of 20 percent, which Western experts worry is a step towards the level required for bombs. Tehran says hoping for nuclear talks "very soon" 2013-01-02T17:15:19Z Iran is refining uranium to a fissile concentration of 20 percent, which Western experts say is a relatively short technical step from the level that would be required for bombs. Russia hopes for six-power nuclear talks with Iran next month 2012-12-20T14:00:50Z Fordow is of particular concern for the West as Iran uses the facility to refine uranium to a fissile concentration of 20 percent, a short technical step from bomb-grade material. Iran may step up underground nuclear work soon: diplomats 2012-11-15T20:13:44Z Iran says it needs 20 percent fissile uranium for a research reactor in Tehran. Iran would need 2-4 months to amass bomb material: think tank 2012-10-08T17:37:42Z Iran now enriches uranium to a 3.5 percent concentration of the fissile isotope U-235 - suitable for nuclear power plants - as well as 20 percent, which it says it needs for a medical research reactor. Iran to enrich uranium to 60 percent if nuclear talks fail: MP 2012-10-02T16:39:15Z "It should be recalled that power cut-off is one of the ways to break down centrifuge machines," he added, referring to the equipment used to increase the proportion of fissile uranium-235 atoms within uranium. IAEA 'infiltrated by terrorists' 2012-09-17T15:23:02Z At the core of the discussions are Iranian efforts to enrich uranium to 20 percent fissile purity, an advance that would bring it close to acquiring weapons-grade material. Iran, EU agree to talk again on nuclear dispute 2012-08-02T20:51:55Z Nuclear weapons need a fissile purity of 90 percent, about the same level as is used to fuel U.S. nuclear submarines. Iran submarine plan may fuel Western nuclear worries 2012-07-05T14:17:11Z Separating the tiny fraction of uranium-235 from the uranium-238 that dominates natural uranium is the major hurdle to making fuel for commercial reactors and fissile material for weapons. Laser plant offers cheap way to make nuclear fuel 2012-07-04T17:20:37.317Z Of the five original nuclear-weapons states within the nuclear Non-Proliferation Treaty, China is the most secretive about its arsenal, its stockpile of fissile material and its nuclear doctrine, analysts say. China to lead talks on nuclear definitions 2012-06-30T01:01:24Z In the short term, the six world powers that are negotiating with Iran want it to stop enriching uranium to a fissile purity close to that needed to produce material for nuclear bombs. Iran says it seeks EU engagement, not stand-off 2012-06-26T11:14:18Z "DELIBERATELY UNGENEROUS" In the immediate term, the powers want Tehran to cease enriching uranium to 20 percent fissile concentration, because such production represents a major technological advance en route to making weapons-grade material. Powers want "diamonds for peanuts": Iran ex-official 2012-06-15T19:09:51Z In the immediate term, the powers want Tehran to stop enriching uranium to 20 percent fissile purity, because such production represents a major technological advance en route to making weapons-grade material. Powers want "diamonds for peanuts:" Iran ex-official 2012-06-15T14:18:30Z A grave concern today is that nuclear weapons or their fissile components may fall into the hands of terrorist organizations, Mr. Levin said. Senator Levin Urges Bigger Cuts to Nuclear Arsenal 2012-06-14T20:03:47Z In the immediate term, they want Tehran to stop enriching uranium to 20 percent fissile purity, because production of such material represents a major technological advance en route to making weapons-grade material. Iran agrees to discuss nuclear proposal in Moscow: EU officials 2012-06-11T22:03:29Z Iran began enriching uranium to a fissile concentration of 20 percent in 2010, saying it needed this to fuel a medical research reactor. Iran has enough uranium for five bombs: expert 2012-05-26T08:57:37Z Chief among such concerns is Iran's ability to enrich uranium to a fissile concentration of 20 percent. Iran, big powers agree to hold more nuclear talks in June 2012-05-25T11:34:21Z Chief among such concerns is Iran's ability to enrich uranium to a fissile purity of 20 percent. Iran, big powers agree to hold more nuclear talks in June 2012-05-25T00:19:03Z The powers' main proposal was for Iran to halt its uranium enrichment to the higher fissile concentration of 20 percent. Iran talks with world powers hit snag over sanctions 2012-05-24T09:35:21Z Iran says it is enhancing the fissile purity to such a degree only for medical research. Detailed, "engaged" Iran nuclear talks go to second day 2012-05-24T01:03:24Z Iran maintains it needs uranium refined to a fissile concentration of 20 percent for its medical isotope reactor. IAEA chief says close to deal with Iran 2012-05-22T19:25:40Z Iran maintains that it needs uranium refined to a fissile concentration of 20 percent for its medical isotope reactor. IAEA chief says close to deal with Iran 2012-05-22T15:06:44Z Iran says it needs uranium enriched to a fissile concentration of 20 percent for its medical isotope reactor. U.N. nuclear chief holds talks in Tehran, hopes for deal 2012-05-21T14:20:42Z Iran says it needs the uranium enriched to a fissile purity of 20 percent for its medical research reactor. Iran may seek "tactical gain" with U.N. nuclear deal 2012-05-18T09:06:00Z Its core issues are nuclear disarmament, a treaty stopping the production of fissile material, assurances that nuclear weapons will not be used on non-nuclear states; and preventing an arms race in space. Disarmament: Dropping fists 2012-03-22T16:10:10Z The U238 does not just sit idly by, however; it transmutes into other fissile elements. The Thing About Thorium: Why The Better Nuclear Fuel May Not Get A Chance 2012-02-16T23:59:05Z Slate′-axe, a slater's tool, a sax; Slate′-clay, a fissile shale.—adjs. Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements) 2012-01-30T03:00:19.113Z The reactor in an ADS contains too little fissile material in its core to sustain a nuclear chain reaction. Reactor-Accelerator Hybrid Achieves Successful Test Run 2012-01-12T16:25:33Z Iran is already refining uranium to a fissile purity of 20 percent - far more than the 3.5 percent level usually required to power nuclear energy plants - above ground at another site. West readies oil stocks release as Iran plans war games 2012-01-07T00:13:18Z The nightmare scenario is that Pyongyang would even sell fissile material—the key ingredient for nuclear bombs— to terrorists if the price is right. Kim Jong Il's Most Dangerous Legacy: A Thriving Nuclear Export Business 2011-12-21T10:05:32Z It appears to us from its use to have been either a quartzite or a fissile limestone. De Re Metallica, Translated from the First Latin Edition of 1556 2011-11-16T03:00:21.977Z Unless a strike succeeded in permanently crippling the Iranian capacity to produce and weaponize fissile material, the grass would only grow back again. Republican Answers on Iran Nukes Face Same Reality as Obama’s 2011-11-14T06:04:14Z Such machines spin at supersonic speeds to increase the fissile isotope ratio. Iran moved nuclear material to bunker: U.N. watchdog 2011-11-09T09:59:35Z Its members are specially distinguished by a prevailing fissile, or schistose, structure which they did not at first possess, and which differs from anything found in unaltered igneous or sedimentary rocks. Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 6 "Geodesy" to "Geometry" 2011-09-19T02:00:10.473Z Tehran said in June that it aimed to triple its capacity to enrich uranium to a higher grade -- 20 percent fissile purity -- which it says will be used to power a medical research reactor. Iran starts moving uranium centrifuges to bunker 2011-08-22T11:28:32Z Now, judging by the description of the article, there probably wasn’t any real danger of this guy building a nuclear reactor – it’s doubtful in the extreme that he had anywhere close to sufficient fissile material. Swedish Man Arrested For Building a Nuclear Reactor In His Kitchen 2011-08-04T12:28:18Z One route to improving nuclear security is clearly on the diplomatic front through arms control; putting a ceiling on arsenals and halting the production of fissile material. In safe hands? 2011-05-23T15:44:05Z Each explosion consumed between 1 and 30 percent of the device’s fissile material, leaving the remaining fuel mixed with debris and melted rock underground, according to the study. Old Soviet Nuclear Site in Asia Has Unlikely Sentinel: The U.S. 2011-05-22T00:56:13Z It’s dangerous because Pakistan is also stockpiling fissile material, or bomb fuel. Fourth Nuclear Reactor at Pakistan's Khushab Site 2011-05-15T05:00:00Z These rocks frequently have a foliated or fissile structure, such as it is presumed would result from a flowing movement within the mass while under great pressure. North America 2011-05-05T02:00:20.027Z With an initial kick from more traditional fissile materials, thorium can set up a self-sustaining “breeder” reaction that produces uranium 233, which is well suited to generation. World Changing Ideas: 20 Ways to Build a Cleaner, Healthier, Smarter World (preview) 2011-05-01T14:15:51.830Z “It’s not that significant — 10 percent or less,” said Kenneth Bromberg, the department’s assistant deputy administrator for fissile materials disposition. New Doubts About Turning Plutonium Into a Commercial Fuel 2011-04-10T23:35:46Z Late-stage Soviet tests there involved superefficient blasts, in which an unusually large percentage of fissile material was consumed, and Russians may fear that American scientists will excavate the tunnels, Mr. Kadyrzhanov said. Old Soviet Nuclear Site in Asia Has Unlikely Sentinel: The U.S. 2011-05-22T00:56:13Z "Indonesia is considering the use of fissile materials in its power plants and dealing with hazardous waste is going to be a problem," adds Hilal. Undeterred by Japan, Earthquake-Prone Indonesia Pursues Nuclear Power 2011-03-30T06:00:00Z The only requirement for a nuke design is that somehow a nuclear chain reaction must occur: A fissile material absorbs a neutron and splits, releasing energy and more neutrons that carry the process on. Building a Better Reactor 2011-03-24T04:45:03Z These nations are seeking to acquire uranium enrichment or reprocessing technologies: useful either for producing fuel for peaceful nuclear reactors or fissile material for nuclear bombs. Do not phase out nuclear power ? yet 2011-03-23T18:50:10.940Z Reactors employing mixed oxide fuel may require extra control rods, made of boron or other neutron-absorbing materials, to slow down more fissile plutonium. Fate of Nuclear Plant in Japan Hangs in the Balance as Melting Continues 2011-03-19T00:15:06.053Z This meant that in the company's view, it was possible that enough fissile uranium was present in the cooling pond in enough density to form a critical mass. Choppers and cannons bring no nuclear relief 2011-03-17T15:02:16Z Clinching a so-called fissile material cut-off treaty would be an important step on the road to a world without nuclear weapons, something President Barack Obama called for in Prague nearly two years ago, Clinton said. Clinton warns terrorists may get fissile materials 2011-02-28T17:12:16Z Most usually the 'cleavage,' as this fissile structure is termed, crosses the bedding at all angles. Geology 2011-02-20T03:00:12.660Z The panel also voiced concern that North Korea might "transfer fissile materials or the means of producing them" to foreign countries due to its shortage of hard currency. China blocks U.N. report on N.Korea nuclear breaches 2011-02-17T21:16:12Z Pakistan insists that existing fissile stocks should also be included to counter India's perceived strategic advantage. U.S. calls for end to global arms control impasse 2011-01-27T14:48:32Z It insists that existing fissile stocks should be included, to counter India’s perceived strategic advantage. | UNITED NATIONS: Secretary General Warns of Nuclear Danger 2011-01-27T04:02:35Z It insists that existing fissile stocks should also be included, to counter India's perceived strategic advantage. Nuclear weapons risk spreading due to impasse: Ban 2011-01-26T16:36:27Z In most sandstones, the lines of bedding are distinct; when they are so numerous as to render the rock fissile, the sandstone is said to be shaly. Geology 2011-02-20T03:00:12.660Z Uranium enriched to a low degree yields fuel for electricity or, if refined to a high level, the fissile core of a nuclear bomb. Big powers leave Iran nuclear talks empty-handed 2011-01-23T07:43:54Z Uranium enriched to a low degree yields fuel for electricity or, if refined to a very high level, the fissile core of a nuclear bomb. Iran nuclear talks enter final day, little to show 2011-01-22T00:56:08Z It was then to be enriched to 20 percent fissile purity and then turned into fuel assemblies for a Tehran medical research reactor. Iran to propose new nuclear fuel swap deal: report 2011-01-20T10:39:10Z Nations have a right to enrich uranium domestically and Iran insists it is doing so only to make fuel and not to make fissile warhead material. Iran permitting some countries to visit nuclear sites 2011-01-04T20:54:00Z The agreement is designed to make it harder for militants to get hold of fissile material that could be used in an atomic bomb. Ukraine sends highly enriched uranium to Russia 2010-12-31T16:07:16Z The neighbouring mountain abounded with a very black fissile aluminous stone. Lachesis Lapponica A Tour in Lapland, Volume 1 2010-12-31T03:00:11.350Z Fissile material A treaty, with verification measures, to end fissile material production was also promised in Prague. Fresh Start 2010-12-22T14:27:45Z Hecker's report adds to worries the North is seeking a second way to obtain fissile material for atomic bombs. U.S. envoy in Asia amid new North Korea nuclear concern 2010-11-21T14:39:00Z Iran, which says it is refining uranium only for an eventual network of civilian nuclear power plants, announced it was refining uranium to 20 percent fissile purity in February, up from 3.5 percent previously. Iran says higher-enriched uranium stockpile rising 2010-10-20T15:13:00Z Heaping pressure on Pakistan, a high-level U.N. meeting called on Friday for talks to start immediately on a treaty to ban production of fissile material used as fuel for atom arms. Nuclear-armed Pakistan becomes chair of IAEA board 2010-09-27T10:18:00Z The lofty mountains, piled one upon another, showed no signs of volcanic fire, but were covered with stones, all of a fissile kind, and by that means easily distinguishable. Lachesis Lapponica A Tour in Lapland, Volume 1 2010-12-31T03:00:11.350Z Secretary-General Ban Ki-moon said there was "broad agreement on the need to immediately start negotiations on a ... treaty banning the production of fissile material." U.N. speakers urge Pakistan to free up arms talks 2010-09-24T20:47:00Z At the moment, only Pakistan and India — and possibly Israel and North Korea — produce fissile material for weapons. UN Session Seeks to Kick-Start Stalled Nuke Talks 2010-09-24T14:54:00Z Instead, support seems to be growing to find another way to tackle the fissile material question, possibly in small-group talks in parallel to the CD sessions. Diplomats see little hope in reviving arms talks 2010-09-19T09:35:00Z The resulting form of uranium soon decays into plutonium, a very potent fissile material. Miniature nuclear reactors might be a safe, efficient source of power 2010-09-14T04:00:00Z They said it would be difficult for monitors to track the large amounts of fissile material set to be produced by the reactor. Russians to Fuel Iranian Reactor 2010-08-14T00:16:00Z Pakistan's refusal since January to launch negotiations on fissile material like plutonium and highly enriched uranium is the latest obstacle. U.N. speakers urge Pakistan to free up arms talks 2010-09-24T20:47:00Z Vietnam signed an initial memorandum of understanding with the Bush administration in 2001 to pursue cooperation with the U.S. on securing fissile materials and developing civilian nuclear power. U.S., Hanoi in Nuclear Talks 2010-08-05T04:14:00Z It did not win backing for new anti-proliferation obligations, such as a legally binding test ban or for an end to the further production of fissile uranium or plutonium for bombs. Nuclear proliferation in South Asia: The power of nightmares 2010-06-24T11:19:00Z This was because their fissile stocks were sufficient. START negotiator sees early Senate ratification 2010-06-03T16:51:00Z "Terrorists could hijack a reactor and directly use it to cause a meltdown or use it to fabricate fissile materials for later use in a weapon," Beránek says. Small Nuclear Reactors Are Becoming Big Business 2010-05-20T21:00:00Z Argentina, Italy and the United Arab Emirates said they were working to install radiation detectors to check cargo for fissile material. Disarmament and counter-proliferation: Old worry, new ideas 2010-04-15T10:52:00Z Push for fissile material treaty A Fissile Material Cut-off Treaty remains elusive. Summing up 2010-04-14T11:02:00Z George Perkovich of the Carnegie Endowment, a think tank, says Pakistan should lift its veto on a ban on the production of fissile materials for bombs. Nuclear proliferation in South Asia: The power of nightmares 2010-06-24T11:19:00Z "Disturbingly, international organized criminal syndicates and criminal gangs are keenly aware of the strong interest of terrorist groups to acquire fissile material." Nuclear Security Summit: Obama Invokes Mushroom Clouds 2010-04-13T08:00:00Z He said that Al Qaeda had been taken in by scams organized by criminal groups — for example, passing off red mercury as fissile material. Ukraine Agrees to Eliminate Stockpiles of Highly Enriched Uranium 2010-04-12T20:40:00Z Secretary-General Ban Ki-moon said on Monday he would propose at this week's nuclear summit that world leaders meet to push for a ban on production of fissile materials for atomic weapons. U.N. chief to seek summit on fissile materials 2010-04-12T16:34:00Z "The United States will seek a new treaty that verifiably ends the production of fissile materials intended for use in state nuclear weapons." Summing up 2010-04-14T11:02:00Z Uranium bombs are simpler: they can be detonated by shooting a slug of fissile material down a gun barrel into a sleeve of the same stuff to achieve critical mass. Obama Should Target Loose Nukes, not Arms Reduction 2010-04-12T16:16:00Z The other is to actually buy in or steal the fissile material needed. Nuclear summit 2010-04-12T00:29:00Z “It’s frankly not as attractive” as uranium, said Ken Bromberg, assistant deputy administrator for fissile materials at the National Nuclear Security Administration, part of the Energy Department. Plutonium Disposal From Disarmament Will Take Decades 2010-04-08T18:18:00Z Many countries support a fissile material cut-off treaty, including the United States. U.N. chief to seek summit on fissile materials 2010-04-12T16:34:00Z The White House hopes the tonal shifts will yield warmer relations with Russia, tougher international sanctions against Iran, and multinational cooperation to secure fissile materials and prevent nuclear terrorism. Modest Advance on Nuclear Control 2010-04-08T10:00:00Z Mr. Obama also wants to negotiate a treaty on fissile materials, and plans to press the Senate to finally ratify the Comprehensive Test Ban Treaty. Obama Completes Arms Control Deal With Russia 2010-03-26T16:41:00Z Mr. Obama also wants to negotiate a treaty on fissile materials and plans to press the Senate to finally ratify the Comprehensive Test Ban Treaty. Treaty Advances Obama?s Nuclear Vision 2010-03-26T00:48:00Z A more pressing deadline is the Nuclear Security Summit in Washington on April 12, aimed at developing mechanisms to secure and eventually eliminate global stocks of fissile material required for building nuclear weapons. Stakes Rise as U.S. and Russia Stall Over Nukes 2010-03-23T00:30:00Z "In addition, we will seek to ratify the Comprehensive Test Ban Treaty and negotiate a treaty to end the production of fissile material for use in nuclear weapons." Obama vows to reduce nuclear arms 2010-03-05T23:10:00Z The Bulletin's statement also cited President Obama's "pragmatic, problem-solving approach," arms reduction talks with Russia, negotiations with Iran over its nuclear enrichment program and support for a fissile material cutoff treaty at the U.N. 2010-01-15T05:00:00Z It would also deprive Iran of enough fissile material to make a bomb, at least for a time. 2010-02-08T00:30:00Z The plan aims to reduce Iran's reserves below the quantity needed for the fissile core of a nuclear weapon, if the material were refined to a high degree of purity. 2010-02-03T02:25:00Z The plan for Iran's low-enriched uranium aims to reduce Iran's reserves below the quantity needed for the fissile core of a nuclear weapon, if the material were refined to a high degree of purity. 2010-02-02T21:21:00Z This would mean no reduction of its LEU reserve to below the quantity needed for conversion into fissile material if it were to be enriched to a high state of purity. 2010-01-20T00:23:00Z General Assembly also called on the conference last December to agree a 2010 work programme including immediate negotiations to ban the production of fissile material, in a resolution sponsored by Canada. 2010-01-19T12:53:00Z According to the reports, the Tehran engineers used thin fibers and a measuring circuit board in place of the fissile material. 2010-01-25T15:26:00Z Mould, the earth of vegetables, is hardened into fissile slate, which being impregnated with bitumen becomes coal. Lives of Eminent Zoologists, from Aristotle to Linnæus with Introductory remarks on the Study of Natural History Other loadstones are of a leaden colour, fissile and not-fissile, capable of being split like slates in layers. On the magnet, magnetick bodies also, and on the great magnet the earth a new physiology, demonstrated by many arguments & experiments The deal aimed to reduce Iran's LEU reserve below the quantity needed for the fissile core of a nuclear weapon, if it were enriched to a high degree of purity. 2010-01-20T00:23:00Z This Crystal is a pellucid fissile Stone, clear as Water or Crystal of the Rock, and without Colour; enduring a red Heat without losing its transparency, and in a very strong Heat calcining without Fusion. Opticks or, a Treatise of the Reflections, Refractions, Inflections, and Colours of Light In these recent formations, as seen in Forfarshire, two or three beds of calcareous marl are sometimes observed separated from each other by layers of drift peat, sand, or fissile clay. Principles of Geology or, The Modern Changes of the Earth and its Inhabitants Considered as Illustrative of Geology They are composed chiefly of greenish-colored fissile sandstones and calciferous grits, in which we meet a few fossils, very imperfectly preserved. The Cruise of the Betsey or, A Summer Ramble Among the Fossiliferous Deposits of the Hebrides. With Rambles of a Geologist or, Ten Thousand Miles Over the Fossiliferous Deposits of Scotland Associated with the earliest ichthyic remains of the Old Red Sandstone, we find vegetable organisms in such abundance, that they communicate often a fissile character to the stone in which they occur. The Testimony of the Rocks or, Geology in Its Bearings on the Two Theologies, Natural and Revealed These hills are sixty-four metres high, and consist of thick horizontal sandstone beds alternating with strata of fissile bituminous tree stems, heaped on each other to the top of the hill. The Voyage of the Vega round Asia and Europe, Volume I and Volume II In the strata now considered, the earth, precipitated with the bituminous matter, being calcareous, has produced a limestone, which, after burning especially, is perfectly fissile. Theory of the Earth, Volume 1 (of 4) The cliffs of this island are composed of a fissile primitive rock, on which sandstone reposes in regular beds. Narrative of a Survey of the Intertropical and Western Coasts of Australia Performed between the years 1818 and 1822 — Volume 2 It is divided into two shelves, of which the upper presents green steatitous slate mixed with amphibole, and the lower, dark-blue slate, extremely fissile, and traversed by numerous veins of quartz. Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3 These masses are fissile, very heavy, and loaded with iron; their streak is whitish, and they produce no effervescence with acids. Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 2 Among the cinders outside the vault were fragments of fissile sandstone, reddened by heat, which were observed to rest on a levelled surface of Nummulitic limestone and to have formed a hearth. The Antiquity of Man Mr. Darwin attributes the lamination and fissile structure of volcanic rocks of the trachytic series, including some obsidians in Ascension, Mexico, and elsewhere, to their having moved when liquid in the direction of the laminae. The Student's Elements of Geology In those not uncommon instances, where a mass of clay-slate, in approaching granite, gradually passes into gneiss, we clearly see that folia of distinct minerals can originate through the metamorphosis of a homogeneous fissile rock. Geological Observations on South America We see in them masses of hardened clay, black, fissile, charged with iron, and covered with a crust, yellow from decomposition, like basalts and amphiboles. Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3 The term "laminated," in this chapter, is applied in these latter senses; where a homogeneous rock splits, as in the former sense, in a given direction, like clay-slate, I have used the term "fissile." Volcanic Islands The fissile limestone of Monte Bolca, near Verona, has for many centuries been celebrated in Italy for the number of perfect Ichthyolites which it contains. The Student's Elements of Geology Cleavage, he observes, may be applied to those divisional planes which render a rock fissile, although it may appear to the eye quite or nearly homogeneous. The Student's Elements of Geology Where masses of fissile and foliated rocks alternate together, the cleavage and foliation, in all cases which I have seen, are parallel. Geological Observations on South America It is for the most part extremely fissile, often affording good roofing-slate. The Student's Elements of Geology Rippled slabs of fissile oolite are used for roofing, and have been traced over a broad band of country from Bradford in Wilts, to Tetbury in Gloucestershire. The Student's Elements of Geology |
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