| 单词 | nuclear reaction |
| 例句 | The Physical Review soon acceded to a system by which it would accept articles on nuclear reactions but keep them in a vault, to be published after the conclusion of the war. Big Science 2015-07-07T00:00:00Z Eventually the time will come when the solar interior is all carbon and oxygen, when at the prevailing temperatures and pressures no further nuclear reactions can occur. Cosmos 1980-01-01T00:00:00Z Fie continued to provide Segre with metal scraps and even acceded to Segre’s request to irradiate a quantity of uranium oxide mailed from Italy so that he could continue searching for nuclear reactions. Big Science 2015-07-07T00:00:00Z A star tens of times more massive than the Sun can stably convert hydrogen to helium for only a few million years before moving briefly on to more exotic nuclear reactions. Cosmos 1980-01-01T00:00:00Z Stars will remain stable like this for a long time, with heat from the nuclear reactions balancing the gravitational attraction. A Brief History of Time: And Other Essays 1988-01-01T00:00:00Z Lawrence’s brusque four-paragraph letter reported deuteron-induced radioactivity in fourteen light elements and speculated brashly that “in these nuclear reactions new radioactive isotopes of many of the elements might be formed.” Big Science 2015-07-07T00:00:00Z At the time that Alpher, Bethe, and Gamow wrote their paper, not much was known about the nuclear reactions of protons and neutrons. A Brief History of Time: And Other Essays 1988-01-01T00:00:00Z The weight of the outer layers of the star is now supported by the high temperatures and pressures generated in the interior nuclear reactions. Cosmos 1980-01-01T00:00:00Z Mark closed his eyes, tried to tamp down the rage that was building inside him like a nuclear reaction. The Kill Order (Maze Runner, Book Four; Origin) 2012-08-14T00:00:00Z The core will compress and heat up further, but there isn’t enough mass to trigger any more nuclear reactions. When the universe began 2012-07-22T12:00:00Z “It’s sort of like the difference between fission and fusion,” said Brian Crano, the director of “Permission,” pausing a moment to try to remember which nuclear reaction was which. Rebecca Hall and Morgan Spector: Together, Onstage and Off 2017-05-25T04:00:00Z Sad: You are having a somewhat nuclear reaction to this slight. Perspective | Ask Amy: Boyfriend has elaborate explanation for suspected cheating 2021-11-11T05:00:00Z And on the current season of “Twin Peaks,” good and evil are forces of electrical energy, born, it seems, from a nuclear reaction and otherworldly intervention. Prestige television post anti-hero is a world of pure good and evil 2017-08-01T04:00:00Z Neutrinos are byproducts of nuclear reactions in stars. News at a glance: Big neutrino detectors, pesky Excel formatting, and a crackdown on lead 2023-10-25T04:00:00Z These are the parts of the plant where nuclear reactions happen, creating energy. Ukraine’s Zaporizhzhia Nuclear Power Plant is Shut Down 2022-09-12T04:00:00Z Like Japan, Canada has struggled to store radiated water that’s a byproduct of nuclear reactions. Granderson: Nuclear power could save our air quality. At what cost to the water? 2023-08-28T04:00:00Z But nuclear reactions, generating energy from the splitting of uranium atoms, are much more efficient. NASA Seeks a Nuclear-Powered Rocket to Get to Mars in Half the Time 2023-07-26T04:00:00Z Thermonuclear supernovae are explosive deaths of white dwarfs caused by runaway nuclear reactions. Some of Earth’s Most Famous Art Started with Stardust 2023-07-04T04:00:00Z Even though the six reactors are now in cold shutdown, they still require water to circulate in their cores to dissipate residual heat from nuclear reactions. Last Reactor at Zaporizhzhia Nuclear Plant Shut Down After Dam Collapse 2023-06-10T04:00:00Z They had a problem with beta decay, this nuclear reaction that seemed to have something missing. The Weirdest Particles in the Universe 2023-06-07T04:00:00Z Energy generation isn't actually a main part of the NIF mission; the facility was intended mostly to trigger nuclear reactions for studying and maintaining the U.S. stockpile of nuclear weapons. What Is the Future of Fusion Energy? 2023-06-05T04:00:00Z Although far less powerful than enriched uranium and incapable of generating a nuclear reaction, depleted uranium is extremely dense — more dense than lead — a quality that makes it highly attractive as a projectile. A look at the uranium-based ammo the U.K. will send to Ukraine 2023-03-23T04:00:00Z Of course, nuclear power has always been the flip side of that other use of nuclear reactions: weapons. New Exascale Supercomputer Can Do a Quintillion Calculations a Second 2023-02-09T05:00:00Z With their army in disarray, Mr. Putin and other Russian officials warned against Ukraine’s use of a so-called dirty bomb: a crude device that spreads radiological material but does not create a nuclear reaction. Fears of Russian Nuclear Weapons Use Have Diminished, but Could Re-emerge 2023-02-03T05:00:00Z While these technologies churn out electric power free of greenhouse gas emissions, they generate an energy stream that is less steady than a traditional power plant fueled by coal, natural gas or a nuclear reaction. Is a Dam in Rural Portugal a Key to Our Alternative Energy Future? 2023-01-03T05:00:00Z Fusion is a nuclear reaction that combines two atoms to create one or more new atoms with slightly less total mass. Why fusion ignition is being hailed as a major breakthrough in fusion – a nuclear physicist explains 2023-01-02T05:00:00Z The breakthrough might also help scientists study nuclear reactions without underground detonations. Turning Sci-fi Into Reality 2022-12-14T05:00:00Z Scientists at the world’s largest nuclear-fusion facility have achieved the phenomenon known as ignition—creating a nuclear reaction that generates more energy than it consumes. Nuclear Fusion Lab Achieves ‘Ignition’: What Does It Mean? 2022-12-13T05:00:00Z The aim of fusion research is to replicate the nuclear reaction through which energy is created on the sun. U.S. to announce fusion energy ‘breakthrough’ 2022-12-11T05:00:00Z Unlike other nuclear reactions, it doesn’t create radioactive waste. Officials to announce long-awaited fusion energy advance 2022-12-12T05:00:00Z With all nuclear reactions stopped, temperatures and pressure inside reactors gradually decline, reducing the required intensity of water cooling of the radioactive fuel. EXPLAINER: Ukraine’s nuclear power plant shutdown cuts risks 2022-09-12T04:00:00Z These forces determine which nuclei are stable and which decay, and they are the basis of the release of energy in certain nuclear reactions. College Physics for AP Courses 2015-08-12T00:00:00Z To describe a nuclear reaction, we use an equation that identifies the nuclides involved in the reaction, their mass numbers and atomic numbers, and the other particles involved in the reaction. Chemistry 2019-02-14T00:00:00Z It does, however, change the chemical composition in its central regions where nuclear reactions occur: hydrogen is gradually depleted, and helium accumulates. Astronomy 2016-10-13T00:00:00Z If cooling systems failed, the nuclear reaction would slow but a reactor would heat up very swiftly. Factbox: Ukraine's battlefield nuclear plant: what are the risks? 2022-08-19T04:00:00Z There are many other regulatory precautions governing permitting, construction, operation, and decommissioning of nuclear power plants due to risks from an uncontrolled nuclear reaction. Environmental Biology 2018-09-06T00:00:00Z Carbon-14 has a half-life of 5730 years and is produced in a nuclear reaction induced when solar neutrinos strike 14 N in the atmosphere. College Physics for AP Courses 2015-08-12T00:00:00Z If the atomic number and the mass number of all but one of the particles in a nuclear reaction are known, we can identify the particle by balancing the reaction. Chemistry 2019-02-14T00:00:00Z And during the red-giant stage, material from the star’s central regions is dredged up and mixed with its outer layers, which can cause further nuclear reactions and the creation of still more new elements. Astronomy 2016-10-13T00:00:00Z Fusion is a nuclear reaction in which two or more nuclei, the centers of atoms, are forced together and combine creating a new larger atom. An Introduction to Geology 2017-01-01T00:00:00Z A functioning reactor requires pumps that circulate water around the core, keeping it cool and moderating the nuclear reaction to avoid a meltdown. Damaged Chernobyl Nuclear Plant, Occupied by Russia, Loses Outside Power 2022-03-09T05:00:00Z The possible nuclear reactions are constrained by the law of conservation of nucleon number. College Physics for AP Courses 2015-08-12T00:00:00Z For instance, we could determine that is a product of the nuclear reaction of and if we knew that a proton, was one of the two products. Chemistry 2019-02-14T00:00:00Z As it does so, it heats up, and new nuclear reactions can begin in the degenerate core. Astronomy 2016-10-13T00:00:00Z If the same nuclear reaction that powers the Sun could be duplicated on Earth, it could provide plentiful energy with small amounts of nuclear waste and no greenhouse gases. European fusion reactor sets record for sustained energy 2022-02-09T05:00:00Z But in recent years there have been incidents in which nuclear reactions have started spontaneously in pockets of these fuel-containing materials, leading to spikes in radiation levels. Damaged Chernobyl Nuclear Plant, Occupied by Russia, Loses Outside Power 2022-03-09T05:00:00Z These photons and electrons induce no nuclear reactions and thus create no residual radioactivity. College Physics for AP Courses 2015-08-12T00:00:00Z They must first be slowed to be absorbed by the fuel and produce additional nuclear reactions. Chemistry 2019-02-14T00:00:00Z Whereas the p-p chain is the reaction producing most of the Sun’s energy, it is not the only nuclear reaction occurring in the Sun’s core. Astronomy 2016-10-13T00:00:00Z An important milestone toward that goal has now been passed: a fusion reaction that derives most of its heat from its nuclear reactions themselves rather than the energy pumped into the fuel from outside. U.S. Project Reaches Major Milestone toward Practical Fusion Power 2022-02-02T05:00:00Z From this unlikely source material, the researchers have also found an important clue to the r-process, the nuclear reactions in stellar blasts that forge much of the heavier elements that make up Earth. Trace seabed plutonium points to stellar forges of heavy elements 2021-05-13T04:00:00Z Both types of weapons produce huge numbers of nuclear reactions in a very short time. College Physics for AP Courses 2015-08-12T00:00:00Z As with chemical reactions, nuclear reactions are always balanced. Chemistry 2019-02-14T00:00:00Z A recent experiment has shown that solar models do predict accurately the number of electron neutrinos produced by nuclear reactions in the core of the Sun. Astronomy 2016-10-13T00:00:00Z The model also explains three of the four fundamental forces of nature: electromagnetism; the strong force, which holds atomic nuclei together; and the weak force which causes nuclear reactions in the sun. Cern experiment hints at new force of nature 2021-03-23T04:00:00Z It generates energy at its center through nuclear reactions that convert hydrogen into helium. An Elemental Problem with the Sun 2020-07-01T04:00:00Z When a star erupts in a supernova explosion, huge numbers of electron neutrinos are formed in nuclear reactions. College Physics for AP Courses 2015-08-12T00:00:00Z What are the two principal differences between nuclear reactions and ordinary chemical changes? Chemistry 2019-02-14T00:00:00Z However, their interiors will never reach temperatures high enough for any nuclear reactions, to take place. Astronomy 2016-10-13T00:00:00Z Modeling that process requires simulating nuclear reactions with centimeter resolution across an object the size of Earth for 100 years or more. The galaxy’s brightest explosions go nuclear with an unexpected trigger: pairs of dead stars 2020-06-04T04:00:00Z Six years ago, physicists used the Borexino experiment in Italy to detect neutrinos from the sun's main nuclear reaction. An Elemental Problem with the Sun 2020-07-01T04:00:00Z The conservation of total baryon number is a more general rule than first noted in nuclear physics, where it was observed that the total number of nucleons was always conserved in nuclear reactions and decays. College Physics for AP Courses 2015-08-12T00:00:00Z Consequently, the energy changes associated with nuclear reactions are vastly greater than are those for chemical reactions. Chemistry 2019-02-14T00:00:00Z Objects of extremely low mass never achieve high-enough central temperatures to ignite nuclear reactions. Astronomy 2016-10-13T00:00:00Z This month’s blast is not believed to have been caused by a nuclear reaction, but by the ignition of rocket fuel being used in the experiment. Russia refuses to share data on blast that caused radiation spike 2019-08-20T04:00:00Z Enriching a supply of uranium means boosting its concentration of the type of uranium that can power a nuclear reaction. AP EXPLAINS: Science of uranium enrichment amid Iran tension 2019-05-16T04:00:00Z In the early hours of 26 April 1986, a problem during a scheduled maintenance test set off an uncontrolled nuclear reaction at the Chernobyl power plant in Soviet Ukraine. Chernobyl: data wars and disaster politics 2019-02-25T05:00:00Z Many different particles can be involved in nuclear reactions. Chemistry 2019-02-14T00:00:00Z In stars with masses higher than about 8 solar masses, nuclear reactions involving carbon, oxygen, and still heavier elements can build up nuclei as heavy as iron. Astronomy 2016-10-13T00:00:00Z At that time, the only practical way to study high-energy nuclear reactions was through the detection and analysis of the interaction of high-energy particles, primarily protons, with atomic nuclei in the atmosphere. Remembering Riccardo Giacconi: A Titan of the Heroic Age of Astronomy 2018-12-31T05:00:00Z The Atomic Energy Lab, complete with radioactive samples, allowed children to create and watch nuclear reactions. Most wanted? Christmas gifts from years ago 2018-12-23T05:00:00Z Energy is generated in the interior of the Sun through sequences of nuclear reactions in which four protons fuse together to form a helium-4 nucleus. Solar neutrinos reveal how the Sun shines 2018-10-23T04:00:00Z A moderator slows neutrons produced by nuclear reactions so that they can be absorbed by the fuel and cause additional nuclear reactions. Chemistry 2019-02-14T00:00:00Z Electric charge has to be conserved in nuclear reactions, Astronomy 2016-10-13T00:00:00Z They are created in nuclear reactions — at power plants, in the center of the sun and amid even more extreme events — when protons accelerate, collide and then shatter in a shower of energetic particles. In a cosmic first, scientists detect ‘ghost particles’ from a distant galaxy 2018-07-12T04:00:00Z Produced by radioactive decays of other particles, they are flooding us from nuclear reactions in the sun, distant supernova explosions and even the Big Bang. It Came From a Black Hole, and Landed in Antarctica 2018-07-12T04:00:00Z Trump’s move immediately set in motion a series of events that will prove just as difficult to control and to predict as an unstable nuclear reaction. Editorials from around New England 2018-05-18T04:00:00Z The function of this component is to protect workers from radiation produced by the nuclear reactions and to withstand the high pressures resulting from high- temperature reactions. Chemistry 2019-02-14T00:00:00Z So, the sunlight given off by the Sun today had its origin as a gamma ray produced by nuclear reactions deep in the Sun’s core. Astronomy 2016-10-13T00:00:00Z When this happens, nuclear reactions will start up outside the core, causing the sun to swell into a red giant that eventually engulfs Mercury and Venus. Sun 'will flare into massive planetary nebula when it dies' 2018-05-07T04:00:00Z In general, nuclear power works by using the heat from a nuclear reaction to generate steam, which drives a turbine to generate electricity. This nuclear power plant has been called a ‘floating Chernobyl,’ but is that just hype? 2018-05-02T04:00:00Z The authority was referring to ruthenium 106, the radioactive isotope identified by the monitoring stations that does not occur naturally and is the product of splitting atoms in a nuclear reaction. Experts fail to find origin of nuclear pollution cloud over Europe 2018-04-16T04:00:00Z When neutrons are required for transmutation reactions, they are usually obtained from radioactive decay reactions or from various nuclear reactions occurring in nuclear reactors. Chemistry 2019-02-14T00:00:00Z Another finding from helioseismology is that the abundance of helium inside the Sun, except in the center where nuclear reactions have converted hydrogen into helium, is about the same as at its surface. Astronomy 2016-10-13T00:00:00Z Bethe also worked on the Manhattan Project during World War II and won the Nobel Prize in Physics in 1967, for contributing to the theory of nuclear reactions. Nobel winners make appearance in Los Alamos 2018-01-17T05:00:00Z Delayed neutron emission adds more neutrons to the stellar environment, that can then induce new nuclear reactions. Atomic Age Began 75 Years Ago with the First Controlled Nuclear Chain Reaction 2017-12-03T05:00:00Z Now 93, Petry is the last surviving witness of the world's first controlled nuclear reaction, 75 years ago Saturday. The atomic age began with a secret test 75 years ago. Meet the last surviving witness. 2017-12-01T05:00:00Z Write the equations for each of these nuclear reactions. Chemistry 2019-02-14T00:00:00Z The lower end of the main sequence stops where stars have a mass just barely great enough to sustain nuclear reactions at a sufficient rate to stop gravitational contraction. Astronomy 2016-10-13T00:00:00Z An atomic bomb uses either uranium or plutonium and relies on fission, a nuclear reaction in which a nucleus or an atom breaks apart into two pieces. What Is the Difference Between a Hydrogen Bomb and an Atomic Bomb? 2017-09-22T04:00:00Z The other way to learn is to monitor the composition of radionuclides released, which are the products of the nuclear reaction that are released into the atmosphere. North Korea nuclear test: 'Tunnel collapse' may provide clues - BBC News 2017-09-03T04:00:00Z The project was centered on investigations into the nuclear reactions of uranium. Honoring a Pioneering Woman in Physics 2017-08-29T04:00:00Z The ship is well-known for its final, secret mission, carrying parts for the atomic bomb nicknamed "Little Boy" as well as enriched uranium fuel for its nuclear reaction. Lost WWII warship USS Indianapolis found after 72 years - BBC News 2017-08-20T04:00:00Z The heating speeds up the nuclear reactions, which provide more heating, and which accelerates the nuclear reactions even more. Astronomy 2016-10-13T00:00:00Z “We want to understand nuclear reactions that happen in stars,” she said. Accelerating Research: JMU Shows off high-tech equipment 2017-07-01T04:00:00Z A thoughtful museum that confronts history honestly is like the control rod inserted into a nuclear reaction, absorbing and nullifying rampant energies. Perspective | What to do with the noose left at the African American Museum? Make it part of the collection. 2017-06-01T04:00:00Z Perhaps, we theorised, when you added them together they achieved a kind of critical mass - like a celebrity nuclear reaction. Why it's hard to be a Kevin in France - BBC News 2017-03-18T04:00:00Z Even though the nuclear reaction had been halted by the automatic shut-off, there was plenty of residual heat - and it was still building up within the primary cooling system. Three Mile Island accident changed his entire life 2017-03-11T05:00:00Z A star of uniform composition from center to surface; it contains hydrogen but has no nuclear reactions going on in the core. Astronomy 2016-10-13T00:00:00Z For his achievement, Dr. Goldwasser received a gift of Chianti wine, the same brand with which Enrico Fermi and his team celebrated when they created the first controlled nuclear reaction in 1942. Edwin Goldwasser, Physicist Who Co-Founded Fermilab, Dies at 97 2016-12-28T05:00:00Z However, when Fermi and his group studied the products of some of the nuclear reactions that they induced, their interpretations were sometimes wrong, as he later acknowledged. Physics: Fallible pontiff of physics : Nature : Nature Research 2016-10-11T04:00:00Z They inserted the control rods—graphite-tipped cylinders of boron carbide that slow or stop a nuclear reaction—too far into the reactor. The Battles of Chernobyl 2016-04-26T04:00:00Z By contrast, a hydrogen bomb derives massive explosive force by fusing hydrogen atoms together, somewhat like the nuclear reaction that occurs in stars, and using radiation to create additional fission. Experts doubt North Korea's bomb was hydrogen-powered 2016-01-06T05:00:00Z A star that has no nuclear reactions going on in the core but is fusing hydrogen to form helium in a shell around the core. Astronomy 2016-10-13T00:00:00Z Hydrogen bombs are much more powerful and difficult to create than strictly atomic weapons, due to the kind of nuclear reaction it employs and the complexity of the process. What North Korea’s Nuke Test Means for the U.S. 2016-01-06T05:00:00Z In the 1930s nuclear physicists worked out that stars were powered by nuclear reactions, and that when those reactions ran out of fuel the stars would collapse. The most beautiful theory 2015-11-25T05:00:00Z The type of nuclear reaction that generates the sun's energy is nowhere near ready to be harnessed for the home. Marty McFly Time-Traveled to This Week. Did 'Back to the Future' Get It Right? 2015-10-20T04:00:00Z These subatomic particles are created in nuclear reactions, such as in the sun and the stars, or in nuclear power plants. A glance at the Nobel Prizes in 2015 2015-10-07T04:00:00Z Deep in the interiors of stars, matter was reheated, nuclear reactions were ignited, and the more gradual synthesis of the heavier elements that we have discussed throughout this book began. Astronomy 2016-10-13T00:00:00Z In the 1960s, theoreticians calculated the number of neutrinos that should be created in the nuclear reactions powering the Sun. Neutrinos: 'superheroes' of the particle world - BBC News 2015-10-06T04:00:00Z The sun was theorised to be powered by nuclear reactions in its core and these produced neutrino particles. Nobel prize for physics 2015: how neutrinos saved the world 2015-10-06T04:00:00Z They are created in nuclear reactions, for example, in the sun, in stars. 2015 Nobel Prize in Physics 2015-10-06T04:00:00Z "The bomb would melt without starting a nuclear reaction." Physics Week in Review: August 29, 2015 2015-08-29T04:00:00Z Since these particles do not participate in nuclear reactions leading to the production of deuterium, the deuterium abundance puts no limits on how many WIMPs might be in the universe. Astronomy 2016-10-13T00:00:00Z The idea was that the tungsten would reflect neutrons, meaning that you’d need less plutonium to get a nuclear reaction going. The Strange Story of the First People to Die From Nuclear Weapons During Peacetime 2015-08-21T04:00:00Z So the surface brightness tells us about the ferocity of the nuclear reactions that were taking place hundreds of thousands of years ago. Nobel prize for physics 2015: how neutrinos saved the world 2015-10-06T04:00:00Z Because it was cooked up in a nuclear reaction, they named it after the Greek word "technos", meaning synthetic, or artificial. The element that can make bones glow - BBC News 2015-05-29T04:00:00Z In macroeconomics the problem is especially bad: we’re better than chemistry was when it was still considering phlogiston but not as advanced as physics is, say, with nuclear reactions and decay. The Fed's Major Problem Is The Simple Ignorance Of Economists 2015-02-22T05:00:00Z Energy seemed to disappear when certain types of nuclear reactions took place, violating the law of conservation of energy. Astronomy 2016-10-13T00:00:00Z The federally supported lab that’s nearly a mile underground in the former Homestake Gold Mine is home to researchers who are studying complex subjects such as nuclear reactions within stars. $5M Sanford lab visitor center in Lead set to open by June 2015-01-28T05:00:00Z The most obvious solution was that the sun’s nuclear reactions had dropped to just one-third of their former levels. Nobel prize for physics 2015: how neutrinos saved the world 2015-10-06T04:00:00Z Like the Noddacks, they sought the element among the weird zoo of matter created in nuclear reactions. The element that can make bones glow - BBC News 2015-05-29T04:00:00Z If reactors switched to sodium, the nuclear reaction itself would change, and they would burn up some of the material that now becomes the most troublesome parts of waste, materials that endure for eons. Betting on the Need, Scientists Work on Lighter, Cleaner Nuclear Energy 2014-12-15T05:00:00Z The computer then calculates the temperature and pressure at every point inside the Sun and determines what nuclear reactions, if any, are taking place. Astronomy 2016-10-13T00:00:00Z Fusion is the ultimate friendly nuclear reaction where atomic power is harnessed without the violence of splitting atoms or fission. Chasing The Holy Grail Of Compact Fusion 2014-10-28T04:00:00Z The uncontrolled nuclear reactions in atomic bombs require a high concentration of fissile material. The element that causes arguments 2014-10-18T04:00:00Z Fusion is a nuclear reaction that releases energy not by splitting heavy atomic nuclei apart—as happens in today’s nuclear power stations—but by fusing light nuclei together. Z machine makes progress toward nuclear fusion 2014-10-10T04:00:00Z Under the reactor’s core, various pistons are positioned to slow or accelerate a nuclear reaction. Idaho brings nuclear test reactor back to life 2014-10-05T04:00:00Z The Sun is our local star, and all the other stars are also enormous balls of glowing gas that generate vast amounts of energy by nuclear reactions deep within. Astronomy 2016-10-13T00:00:00Z Because of neutron capture, shown in the figure above, other elements produced during the nuclear reactions include the heavy actinide elements, the last row in the periodic table – plutonium, americium, neptunium, and so on. A Nuclear Primer -- It's All About Uranium 2014-09-20T04:00:00Z The controlled nuclear reaction at Sizewell B generates some three gigawatts of heat a day - the equivalent of more than three times the energy given off by the bomb that destroyed Hiroshima. The element that causes arguments 2014-10-18T04:00:00Z Aging components, such as the conventional explosives that trigger the nuclear reactions and electronic arming systems, would be replaced. NATO nuclear drawdown now seems unlikely 2014-09-19T04:00:00Z Just one step more purified than raw uranium ore found in the ground, yellowcake emits little radioactivity and is composed of only 0.7 percent U-235, the isotope required for a nuclear reaction. The Uranium Sting: Did Homeland Security Catch a Smuggler or Create One? 2014-09-11T04:00:00Z This means they are the hottest inside and the best at generating energy from nuclear reactions deep within. Astronomy 2016-10-13T00:00:00Z It is important to note that a dirty bomb is not a nuclear device, and no nuclear reaction occurs. The Biggest Threat Dirty Bombs Pose is Panic 2014-09-11T04:00:00Z Other nuclear reactions in the Sun also produce neutrinos, and 100 billion of the particles bombard each square centimetre of Earth every second. Long-sought neutrinos answer burning question about the Sun 2014-08-26T04:00:00Z Images like this one, shot with NASA’s Hubble Telescope, reveal the onset and aftermath of a “weaker” supernova, which happens when something changes in the core of a star and sets off a nuclear reaction. Hubble Finds Star System Linked To 'Zombie Star' 2014-08-06T04:00:00Z The graphite bricks are integral to UK nuclear power stations and they act to moderate the nuclear reaction; it will not function without them. Nuclear plant safety limit 'eased' 2014-06-03T04:00:00Z Objects in which no nuclear reactions can take place are planets. Astronomy 2016-10-13T00:00:00Z It accounts for the huge amounts of energy released in nuclear reactions, and the huge amount you’d need to inject to turn energy into matter. 'Einstein Was Right: You Can Turn Energy Into Matter' 2014-05-19T04:00:00Z When briefly compressed by the laser pulses, the isotopes fused, generating new particles and heating up the fuel further and generating still more nuclear reactions, particles and heat. Fusion energy milestone reported by California scientists 2014-02-13T01:31:00Z When briefly compressed by the laser pulses, the isotopes fused, generating new particles and heating up the fuel further and generating still more nuclear reactions, particles and heat. Fusion energy milestone reported by California scientists 2014-02-12T17:52:00Z The star slowly shrinks and fades until it reaches the main sequence, the stage when nuclear reactions at the stellar core convert protons into helium and supply the star with all of its energy. A Pair of Stellar Newborns Shine Brightly 2013-11-01T14:15:00.517Z Heavy water is water with an extra neutron, useful in moderating a nuclear reaction. Iran Building Un-Bombable Reactor 2013-10-29T08:35:30Z "The spent fuel pool cooling system is designed only to remove decay heat, not heat from an ongoing nuclear reaction." Insight: After disaster, the deadliest part of Japan's nuclear clean-up 2013-08-14T01:28:49Z It's possible to trigger a nuclear reaction much like beta decay in which instead of emitting an antineutrino, a neutron absorbs a neutrino and then turns into a proton and an electron. Are Neutrinos Their Own Antiparticles? 2013-07-16T22:50:00Z Even “low energy nuclear reaction” is a problematic name. Why "Cold Fusion" Has to Die 2013-07-15T10:50:00Z But if low energy nuclear reactions are so commonplace, why haven’t scientists noticed them before? Tiny Nuclear Reactions Inside Compact Fluorescent Bulbs? 2013-03-14T16:35:03Z And instead of pumping heavy water into the reactor to moderate the nuclear reaction and absorb the thermal energy being released, Iran said it plans to use “light water,” just ordinary H2O. Iran Building Un-Bombable Reactor 2013-10-29T08:35:30Z In nuclear reactions this might be Uranium-235; on the Web, it’s data. How BYOD and Big Data are Changing Marketing 2013-02-11T15:46:12Z In modern times, it’s been used to cool nuclear reactions, as an ingredient in dental amalgams, and before the advent of digital thermometers, the devices were filled with mercury. Cold Case Files: Tycho Brahe Not Poisoned After All 2012-11-19T13:45:03.780Z They were looking for brown dwarfs, objects too big to be classified as planets, but too small to ignite the nuclear reactions that would qualify them as full-blown stars. Lost in Space: A Starless Planet Floats Alone 2012-11-14T13:35:33Z In a recent research paper, he also argued that the material should be made useless for making bombs by diluting it with a plentiful form of uranium that will not sustain a nuclear reaction. Uranium 233 Disposal Proves a Problem 2012-09-24T01:56:06Z Eventually, all this extra gas increases the white dwarf's mass enough to trigger runaway nuclear reactions that detonate the white dwarf. Red Giants and White Dwarfs Make Explosive Stellar Pairings 2012-08-23T21:15:00.213Z Such a supernova is supposed to result when a larger companion star dumps material onto the white dwarf, triggering a runaway nuclear reaction that annihilates the small star. ScienceShot: No Star Left Behind 2012-08-17T17:19:00Z Unfortunately, or fortunately, depending on your view, climate change is less immediately tangible than gravity or a nuclear reaction, so it is not so clearly obvious that is true. Guest Post: Rick Santorum and Climate Change 2012-02-16T19:45:12.093Z Ratios of other xenon isotopes also point to a fast nuclear reaction that involved uranium. Isotopes Hint at North Korean Nuclear Weapons Tests in 2010 2012-02-03T20:15:16.477Z For example, he said, the United States allegedly led a ban on selling software to Iran that could be used for calculating nuclear reactions. Murders unlikely to slow Iran?s nuclear efforts 2012-01-18T18:20:24.667Z Such studies would be needed if they wanted to compress uranium to the critical mass needed for a self-sustaining nuclear reaction. Iran?s nuclear plan revealed 2011-11-16T18:20:26.600Z Any nuclear reaction would likely be taking place on a localized basis, ... Japan Detects Xenon Release at Plant 2011-11-03T01:28:19Z The unexpected bursts — something akin to flare-ups after a major fire — are extremely unlikely to presage a large-scale nuclear reaction with the resulting large-scale production of heat and radiation. Bursts of Fission Detected at Fukushima Reactor in Japan 2011-11-02T20:32:37Z But they are all around us—the sun produces so many neutrinos as a by-product of nuclear reactions that many billions pass through your eye every second. Particles Found to Travel Faster than Speed of Light 2011-09-22T21:45:04.180Z Although a pre-main-sequence star shines mostly through gravity, nuclear reactions that operate at relatively low temperatures destroy lithium, so mature stars like the sun have almost none. Baby Star Found on Earth's Doorstep 2011-09-06T22:05:08Z At the cores of these hot giants, nuclear reactions forged those three primordial elements into heavier ones, including carbon, oxygen, iron and more. The impossible star 2011-09-06T16:35:00Z Fast reactors reduce radioactive waste compared with existing operational designs by using most of the fuel during the nuclear reaction, according to the World Nuclear Association. China’s Nuclear Reactor Links to Grid After 40-Year Research 2011-07-21T09:23:01Z The technology reduces radioactive waste compared with existing operational designs by using most of the fuel during the nuclear reaction. China Connects Fast Nuclear Reactor to Electricity Grid 2011-07-21T05:23:01Z These conditions are very similar to the conditions under which nuclear reactions are sustained in manmade nuclear reactors. Nature's Nuclear Reactors: The Two Billion Year Old Natural Fission Reactors in Gabon, Western Africa 2011-07-13T11:15:00.240Z Iran goes nuclear Self-sustaining nuclear reactions have begun inside Iran's first commercial nuclear power plant. Seven days: 19 May 2011 2011-05-18T17:20:19.287Z And peaceful nuclear reactions are in a sense trying to control the bomb.” Safer Nuclear Reactors Impeded By Marketplace, Expert Says 2011-04-22T13:24:12Z The power station's two can be shut down by inserting control rods, or injecting nitrogen gas, to halt the nuclear reaction. Nuclear shutdown system on trial 2011-04-21T07:23:44Z Supercomputers are often used for complex calculations such as climate modeling or to simulate nuclear reactions. Can Supercomputers Help Japan Predict Earthquakes? 2011-04-07T18:33:57Z Fortunately, much of that is produced by nuclear reactions in stars, and such stellar neutrinos have relatively low energies. Astrophysics and alien intelligence: Talking to the neighbours 2011-04-07T10:58:14Z This could be evidence that fuel has clumped together into sufficiently large chunks to briefly restart nuclear reactions, says Ferenc Dalnoki-Veress, a physicist at the Monterey Institute of International Studies in California. Japan's long road ahead 2011-04-06T17:20:25.520Z Speaking of nuclear reaction, please don't be cross when I tell you that I had lunch with Michael Winner last week. May I have your attention, please? 2011-04-02T23:04:07Z Three workers at a separate Japanese plant received high doses of radiation in 1999 from a similar nuclear reaction, known as ‘criticality.’ Fukushima Workers Threatened by Heat Bursts; Sea Radiation Rises 2011-03-31T06:04:04Z It’s also required to be able to deal with the possiblibility of any type of nuclear reaction happening in the pool itself. U.S. nuclear fuel rods to sit in pools -- like those that failed in Japan -- until 2050 2011-03-30T16:55:45Z These, Tepco conceded, were what one might expect from nuclear reactions inside the plant. Long game 2011-03-29T12:51:34Z A Japanese nuclear expert said the main risk was from continued radiation leaks, and the risk of criticality, or a self-sustaining nuclear reaction, was low. Japan nuclear crisis drags on but experts hopeful 2011-03-24T10:18:30Z In Chernobyl, the explosion took place because the nuclear reaction was not halted, unlike in Fukushima, where the reactor was automatically shut down when the earthquake occurred. Japan iodine release lower than Chernobyl: expert 2011-03-23T15:28:02Z Tokyo Electric Power Co., the Fukushima Dai-Ichi plant’s operator, and Japan’s nuclear watchdog, dismissed the threat of renewed nuclear reactions, three weeks after an earthquake and tsunami triggered an automatic shutdown. Fukushima Workers Threatened by Heat Bursts; Sea Radiation Rises 2011-03-31T06:04:04Z Once the whole metallic pool liquefied, Mr. Bolshov said, heat from the continuing nuclear reaction would create currents, swirling the mixture against water-cooled steel walls. Nuclear Industry in Russia Sells Safety, Taught by Chernobyl 2011-03-22T16:58:30Z In April 2009, a control rod—the shutdown device used to stop the nuclear reaction in a plant's core—malfunctioned in Reactor No. 3 due to a leaking valve. Japan Plant Had Troubled Past 2011-03-21T03:47:19Z These tiny products of nuclear reactions are capable of causing large-scale damage in the body if they make it inside through inhalation, ingestion or even a cut. Health Risk Fears Escalate as Japan Nuclear Plant's Radioactive Release Remains Uncertain 2011-03-18T20:45:02.373Z Can a reactor melt down once the nuclear reaction is stopped? What Happens During a Nuclear Meltdown? 2011-03-15T14:15:00.257Z Which means there's no longer a nuclear reaction. Nuclear Experts Explain Worst-Case Scenario at Fukushima Power Plant 2011-03-13T02:45:00.297Z A large explosion was seen at the plant with debris blow out from the building Control rods shut off the nuclear reaction. Japan's nuclear picture unclear 2011-03-12T13:44:17Z The nuclear reaction facility is surrounded by a steel storage machine, which is then surrounded by a concrete building. Radiation leaking from Japan's quake-hit nuclear plant 2011-03-12T13:45:02.787Z A portion of the reactor's fuel rods, which create heat through a nuclear reaction, have become exposed due to the cooling-system failure. Japan Reactor Faces Meltdown Threat 2011-03-12T07:15:30Z How do you turn off a nuclear reaction? What Happens During a Nuclear Meltdown? 2011-03-15T14:15:00.257Z If it were a mere 4% bigger or smaller than it is, stars would not be able to sustain the nuclear reactions that synthesise carbon and oxygen atoms. The nature of the universe: Ye cannae change the laws of physics 2010-09-02T10:46:00Z The final step is bringing the fuel rods closer together to begin the nuclear reaction. Russia Sets Date for Key Iran Nuclear Step 2010-08-13T14:30:00Z Splitting a single uranium atom in a nuclear reaction produces 1 million electron volts. Atom Smasher Will Help Reveal 'The Beginning' 2010-03-31T14:19:00Z And the whole works would blow up with the efficiency of the calculated explosion of nuclear reaction. The Man Who Staked the Stars The heavy-metal atomic plant does almost the same thing, except that it uses nuclear reactions instead of chemical reactions to produce the heat. Damned If You Don't Then other nuclear reactions begin to take place, and, due to the increased transparency of the star, a supernova is produced. Islands of Space In the last two years, the first of the nuclear reaction mass engines had hit the roads. Code Three This produces — on an atom-by-atom scale — 7 million times more power than a single atom in a nuclear reaction, Schewe said. Atom Smasher Will Help Reveal 'The Beginning' 2010-03-31T14:19:00Z In addition, the scientists were concerned about the possible effects if the conventional explosives in a nuclear device, particularly the more complex implosion-type device, failed to trigger the nuclear reaction when detonated over enemy territory. Project Trinity 1945-1946 |
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