Hybrid nuclear fusion fission hybrid nuclear power is a proposed means of generating power by use of a combination of nuclear fusion and Nuclearfissionfission processes. The concept dates to the 1950s ... supplies of fissionables, or commercial nuclear fuel and waste streams. Fusion driven fission ... Fission Energy Production and Transmutation of Nuclear Waste C.D. Bowman and J. Magill https lasers.llnl.gov ... ?AddInterest 1284 Nuclear Fusion Fission Hybrid Could Destroy Nuclear Waste And Contribute to Carbon ... hybrid cite journal author Gerstner, E. title Nuclear energy The hybrid returns year 2009 journal ... fusion reactor, optimising for nuclear waste disposal versus power generation. The principles behind ... yield fission reaction close to 100 in the surrounding subcritical fissionable blanket, the net yield from the hybrid fusion fission process can provide a targeted gain of 100 to 300 times the input ... to generate power, and also consume existing stockpiles of nuclear fissionables and waste products. Unlike a conventional fission reactor , the fusion hybrid can consume almost all of the uranium fuel without Enriched uranium enrichment or Nuclear reprocessing reprocessing . This has advantages for nuclear non proliferation non proliferation , as enrichment and reprocessing technologies are also associated with nuclear weapons production. The low fuel consumption, lack of need for enrichment ... required will increase the construction cost of the reactor. Use to dispose of nuclear waste The surrounding ... or spent nuclear fuel . This offers currently the only means of active disposal versus storage of spent nuclear fuel without reprocessing. Activation product Fission by products produced by the operation of commercial light water nuclear reactors LWR s are long lived and highly radioactive, but they can ... and less of a risk for nuclear proliferation . The waste would contain significantly reduced concentrations ... fissile materials, depleted uranium, and spent nuclear fuel. Safety In contrast to current commercial ... more details
Nuclearfission products are the atomic fragments left after a large atomic nucleus Nuclearfission fissions ... radiation . However, as the fission products approach stable nuclear conditions, the last one or two ... atom, and also on the energy of the initiating neutron. ref name NuclearFission Yield cite web url http www.science.uwaterloo.ca cchieh cact nuctek fissionyield.html title NuclearFission Yield accessdate 2009 05 13 ref In general the higher the energy of the state that undergoes nuclearfission ... but tends to alternate. Note that the curve against mass number is smooth. ref name NuclearFission ... had occurred. More details are provided in the natural nuclearfission reactor linked article . Fission ... reveal clues about the bomb s design. The largest source of fission products is from nuclear reactor s. In current nuclear power reactors, about 3 of the uranium in the fuel is converted into fission ... 137 are used in medical and industrial radioactive source s. Nuclear reactor control Some fission ... to nuclear reactor control. Nuclear reactor poisons Main Nuclear poison Main Iodine pit Some of the fission ... cite web url http atom.kaeri.re.kr title Nuclear Data Evaluation Lab accessdate 2009 05 13 ref For fission ... nuclear detonation , where all the fission products are dispersed. Fission products in power reactors In a nuclear power reactor, the main types of radioactivity are fission products, actinide s and activation ... use. Fission occurs in the nuclear fuel, and the fission products are primarily retained within the fuel ... is very low. Fission products in nuclear weapons Nuclear weapon s use fission as either the partial ... in the total fallout radioactivity. The immediate fission products from nuclear weapon fission are essentially ... products from a power reactor. Almost no Cs 134 is formed by nuclearfission because xenon 134 is stable ... , gamma ray s and neutrino s. The two smaller nuclei are the fission products . See Fission products by element . Formation and decay The sum of the atomic weight of the two atoms produced by the fission ... more details
of 16 sites at which self sustaining nuclearfission reactions took place approximately 2 1,000,000,000 ... nuclearfission reactors were discovered in the region. Fission product isotope signatures Nd Image ... with that for fission product ruthenium which is the result of the Nuclearfissionfission of sup ... from the nuclearfission caused the groundwater to boil away, which slowed or stopped the reaction ... waste disposal the natural nuclearfission reactors in Gabon Africa journal Comptes Rendus ... L. Forward , natural nuclearfission as opposed to solar power is revealed as the power source of the biosphere of a trans Neptunian object trans Neptunian dwarf planet . A natural nuclearfission ... . In 1956, a natural nuclearfission reactor figured in Tom Swift, Jr. Tom Swift in the Caves of Nuclear ... Fission Reactor Category Nuclear reactors Category Geography of Gabon Category Nuclear physics Category ...Image Gabon Geology Oklo.svg right thumb 400px Geological situation in Gabon leading to natural nuclearfission reactors br 1. Nuclear reactor zones br 2. Sandstone br 3. Uranium ore layer br 4. Granite A natural nuclearfission reactor is a uranium mineral deposit deposit where analysis of isotope ratio s has shown that self sustaining nuclear chain reaction s have occurred. The existence of this phenomenon ... under which a natural nuclear reactor could exist had been predicted in 1956 by Paul Kuroda. ref cite journal last Kuroda first P. K. authorlink coauthors year 1956 month title On the Nuclear ... 2005 month November title The Workings of an Ancient Nuclear Reactor journal Scientific American volume issue pages id url http www.sciam.com article.cfm?id ancient nuclear reactor accessdate quote ..., P. Blanc, P. L. year 1996 month title Natural fission reactors in the Franceville Basin, Gabon ... meticulously account for all fissionable isotopes to assure that none are diverted for nuclear weapon .... This loss in sup 235 sup U is exactly what happens in a nuclear reactor. A possible explanation ... more details
From MoS DAB use ONE LINK per entry, SHORT descriptions. AVOID piping, external links, redlinks with little potential wiktionary fission Fission is a splitting of something into two parts. Fission may refer to In physics, nuclear fission is a process where a large atomic nucleus such as uranium is split into two smaller particles. In biology, fission biology is the subdivision of a cell or a multi cellular body into one or more parts and the regeneration of each of the parts into a complete individual. In anthropology , fission is the process whereby a nation state divides and becomes multiple states Other uses Fission band , a Swedish melodic death metal band disambig da Fission flertydig de Fission lt Skilimas no Fisjon ... more details
unreferenced date March 2009 Fast fission is nuclearfissionfission that occurs when a heavy atom absorbs a high energy neutron , called a fast neutron , and splits. Most fissionable materials need thermal neutron s, which move slower. Fast reactors vs. thermal reactors Fast neutron reactor s use fast fission to produce energy, unlike most nuclear reactor s. In a conventional reactor, a Neutron moderator moderator is needed to slow down the neutrons so that they are more likely to fission atoms. A fast neutron reactor uses fast neutrons, so it does not use a moderator. Moderators may absorb a lot of neutrons in a thermal reactor , and fast fission produces a higher average number of neutrons per fission, so fast reactors have better neutron economy making a plutonium breeder reactor possible. However, a fast neutron reactor must use relatively highly enriched uranium or plutonium so that the neutrons ... the energy of the state that undergoes nuclearfission, the more likely a symmetric fission is, hence ... uranium 238 , do not usually undergo fission when struck by slow neutrons, but do split when struck ... and tritium have still higher energy than the fast neutrons produced in a nuclear reactor ... expedient of adding layers of cheap natural uranium. In fact, fast fission of uranium 238 provides a large part of the explosive yield, and Nuclear fallout fallout , in many designs of hydrogen bomb. Fast fission of uranium 238 does also occur in fission bomb s but to a much lesser extent than in hydrogen bombs . Differences in fission product yield A graph of fission product yield against the mass number of the fission fragments has two pronounced but fairly flat peaks, at around 90 to 100, and 130 to 140. With thermal neutrons, yields of fission products with mass between the peaks, such as Cd ... s. The curves for the fission of the later actinides tend to make even more shallow valleys. In extreme cases such as sup 259 sup Fm, only one peak is seen. Category Nuclear physics ru ... more details
Cold fission or cold nuclearfission is defined as involving fission events for which fission fragments have such low excitation energy that no neutron s or gamma s are emitted. Cold fission events have so low a probability of occurrence that it is necessary to use a high flux nuclearNuclear reactor technology reactor to study it. The first observation of cold fission events was in experiments on fission induced by thermal neutrons of uranium 233 , uranium 235 ref C. Signarbieux et al. . http hal.archives ... emitted in binary cold fission of 252Cf , Journal Physics G Nuclear and Particle Physics, Volume ......27G Tip model of cold fission , Nuclear Physics A, Volume 530, Issue 1 July, 1991, DOI 10.1016 ... by detectors. The fact that cold fission preserves nuclear mass energy mass until the fission fragments reach the detectors permits the experimenter to better determine the fission dynamics, especially the aspects related to Coulomb and shell effects in low energy fission. ref Modesto Montoya, http ... content gw7v12v1713250r7 Mass and kinetic energy distribution in cold fission of sup ... experiments on cold fission were also done involving sup 248 sup Cm ref A Sandulescu et al. http www.iop.org EJ abstract 0954 3899 22 7 003 The cold fission of 248Cm , Journal of Physics. G Nucear ... abstract PRC v57 i5 p2516 1 Cold fission description with constant and varying mass asymmetries , Physical ... fission phenomena lies in the fact that fragments reaching detectors have the same mass that they obtained at the scission configuration, just before the attractive but short range nuclear force ... in thermal neutron induced cold fission of U 233, U 235, and Pu 239 , Radiation Effects and Defects ... content w5u431755126g7h6 Coulomb effects in low energy fission Zeitschrift f r Physik A Hadrons ... of fragments and compare them to experimental results. References Reflist DEFAULTSORT Cold Fission Category Nuclear chemistry Category Nuclear physics ... more details
to accelerate at a lower rate for long periods of time. spacecraft propulsion Nuclear propulsion Category Nuclear spacecraft propulsion fr Propulsion par fragments de fission ...Unreferenced date March 2008 The fission sail is a type of spacecraft propulsion proposed by Robert Forward that uses nuclearfissionfission fragments to propel a large solar sail like craft. It is similar in concept to the fission fragment rocket in that the fission by products are directly harnessed as working mass , and differs primarily in the way that the fragments are used for thrust. In the fission sail, the rocket is built in the form of a two layer sheet, with some sort of absorber on one side, and nuclear fuel on the other. Atoms in the fuel that decay will release their fragments in random, but opposite, directions. In the simple case where the decay releases the fragments front and rear , the rearward moving fragment generates thrust directly, while the frontward moving one is absorbed in the front half of the sail, also contributing thrust. The system must be built very large in order to ensure that those fragments that are not moving directly to the front of rear nevertheless tend to hit the sail somewhere. A sail several kilometers on a side would have fairly good capture ratios . The sail is not a nuclear reactor , and relies on natural decay rates for energy release. The thrust from such a system will always be very low, albeit extremely efficient. Another problem is that the sail receives the energy equally over the entire sail surface, and thus can t be steered. This differs from a solar sail, where tilting the sail to the sunlight can produce a sideways thrust for steering. Forward proposed the system as an add on to existing solar sails. Close to stars where the light density is high the sails work fine, but as they move past about 2 astronomical unit AU their thrust is too low to be useful. Forward suggested that coating the sail with fissionable material ... more details
, 235 for U 235 . As the name suggests, spontaneous fission gives the same result as induced nuclearfission . However, like other forms of radioactive decay, it occurs due to quantum tunneling , without the atom having been struck by a neutron or other particle as in induced nuclearfission. Spontaneous ... of Nuclear weapon design Implosion type weapon implosion method . Spontaneous fission can occur ...Spontaneous fission SF is a form of radioactive decay characteristic of very heavy isotope s. It is theoretically ... unit s u , i.e. elements near ruthenium. In practice, however, spontaneous fission is only energetically ... fission are the high atomic number actinide elements , such as mendelevium and lawrencium ... fission mode of decay does occur, but it is not seen for the majority of radioactive breakdowns ... fission can occur is approximately math hbox Z 2 hbox A ge47. math ref cite book last Krane first Kenneth S. title Introductory Nuclear Physics publisher John Wiley & Sons year 1988 pages 483 ... fission can initiate a chain reaction. Also, radioisotopes for which spontaneous fission is a nonnegligible ... as the fissions give a negligible reduction of the amount of nuclei that can spontaneously fission, this is a Poisson process for very short time intervals the probability of a spontaneous fission is proportional to the length of time. The spontaneous fission of uranium 238 leaves trails of damage in uranium bearing minerals as the fission fragments recoil through the crystal structure . These trails, or fission tracks , provide the basis for the radiometric dating technique known as fission track dating . Spontaneous fission rates Spontaneous fission rates ref cite book last Shultis first J. Kenneth coauthors Richard E. Faw title Fundamentals of Nuclear Science and Engineering publisher Marcel ... life Fission prob. per decay Neutrons per fission Neutrons per g.s SimpleNuclide Link Uranium 235 7.04x10 ... production. SimpleNuclide Plutonium 240 s high rate of spontaneous fission events makes it an undesirable ... more details
File Binary fission.svg 180px right thumb Binary fission In biology, fission is the subdivision of a body, population, or species into parts and the regeneration of those parts into separate individuals. ref name Carlson07 cite book last Carlson first B. M. title Principals of regenerative biology. year 2007 publisher Elsevier Academic Press pages 379 isbn 0123694396 ref ref name Boulay10 cite journal last1 Boulay first1 R. L. last2 Galarza first2 J. A. last3 Che first3 B. last4 Hefetz first4 A. last5 Lenoir first5 A. last6 van Oudenhove first6 L. last7 Cerda first7 X. title Intraspecific competition affects population size and resource allocation in an ant dispersing by colony fission. journal Ecology volume 91 issue 11 pages 3312 3321 year 2010 doi 10.1890 09 1520.1 url http www.esajournals.org doi full 10.1890 09 1520.1 ref ref name Hubbell03 cite journal last Hubbell first S. title Modes of speciation and the lifespans of species under neutrality a response to the comment of Robert ... url http onlinelibrary.wiley.com doi 10.1034 j.1600 0706.2003.12450.x abstract ref Binary fission , or prokaryotic fission , is a form of asexual reproduction and cell division used by all prokaryotes ... fission. To be specific, binary fission cannot be divided into prophase , metaphase , anaphase ... after having been cut in half, is also not the same as binary fission. Neither is vegetative reproduction of plants. Process Image Binary fission anim.gif thumb left Animation showing the complete process of binary fission. Binary fission begins with DNA replication . DNA replication starts from an origin ... cell. This separates the parent cell into two nearly equal daughter cells, each having a nuclear ... by eukaryotic organelles The use of binary fission by Eukaryotic organelle s such as mitochondria , chloroplast s, and peroxisomes is not yet clear. References reflist DEFAULTSORT Binary Fission Category ... simple Binary fission ... more details
Infobox webcomic title Fission Chicken image Image FisChic.jpg caption Fission Chicken has problems with the TV. Art by J.P. Morgan. author J.P. Morgan cartoonist J.P. Morgan url http www.fissionchicken.com status Weekly began 1987 online April 16, 2006 ended genre Superhero , Anthropomorphism Anthropomorphic Parody ratings Fission Chicken is a comic book and webcomic character created by J.P. Morgan cartoonist J.P. Morgan 1957 2010 . Fission Chicken is a short tempered superhero chicken who can fly, is extremely strong , bulletproof , and can project power bolts from his hands. Starting in 1987, Fission Chicken appeared in numerous stories published in the comic book Critters Fantagraphics Books , as well as his own series from the same publisher. Other appearances over the years include Plan Nine from Vortox MU Press , appearances in Furrlough Radio Comix , Valiant Varmints and SFA Spotlight 14 Shanda Fantasy Arts . Pages by J.P. Morgan can also be read on the Fission Chicken website. Fission Chicken Fish for short fights a continuing battle against weird monsters and cultural brain death. Notably, he has battled the mind control attempts of Vortoxians a malevolent race of alien marketing experts , the Ditsy entertainment empire a parody of The Walt Disney Company , and Video Zombies. Some unusual opponents he has fought include the Ether Bunny a rabbit bank robber who uses airborne incapacitating agents on his victims , Percival Ulmer P.U. Evolcraft a somewhat deranged occultist and a satire on H. P. Lovecraft , ambulatory living toilets, the movie monster Ferdie Cruller a pun on Nightmare on Elm Street Freddy Kruger , the Richard Sharpe Shaver Dero a subterranean race ..., Fission Chicken does not use an alias to hide his identity, and simply goes by the name Fission ... in New Jersey, and his friend Skip Squirrelhard is his upstairs neighbor. Fission Chicken creator John ... Rovin Rovin, Jeff . Fission Chicken entry in The Illustrated Encyclopedia of Cartoon Animals Prentice ... more details
Orphan date December 2010 Fission Wall coor dm 85 52 S 155 12 W is a 1,400 m high granite cliff on the north face of Mount Griffith , Hays Mountains , in the Queen Maud Mountains . The feature was climbed on November 16 , 1987 , by a United States Antarctic Research Program USARP Arizona State University geological party led by Edmund Stump . The name derives from granite samples collected on the wall at 100 m spacing for dating by the fission track method. usgs gazetteer Category Geography of Antarctica EAntarctica geo stub ... more details
Infobox musical artist See Wikipedia WikiProject Musicians Name Fission Img Img capt Img size Landscape Background group or band Alias Origin Sweden Genre Thrash metal , melodic death metal Years active 2002 present Label Napalm Records Napalm Associated acts URL Current members Andreas Hedlund Vintersorg br Benny H gglund Past members Notable instruments Fission is a Sweden Swedish melodic death metal band formed in 2002. The band began as Benny H gglund s personal project, with the hopes of fusing melody and aggression into his music. After writing some material, he decided to seek aid from Andreas Hedlund of Vintersorg , the band in which H gglund plays live session drums. After recording a two track demo with Benny handling all instrumentation and Andreas handling vocal duties, they signed on with Austrian label, Napalm Records . Benny continued writing all of the songs for their first full length, while Andreas provided all of the lyrics, vocals, keyboards, and sound effects. They released their first full length Crater album Crater on April 27, 2004. ref http fission.se ibiography.htm Fission.se Feb 2005 ... Biography February 2, 2005. ref Discography Crater album Crater 2004 Pain Parade 2008 References reflist External links http fission.se Official website MySpace fissionsweden Fission http www.napalmrecords.com promo fissionp.html Fission at Napalm Records DEFAULTSORT Fission Category Swedish melodic death metal musical groups Category Musical groups established in 2002 metal music stub de Fission Band ... more details
Infobox album See Wikipedia WikiProject Albums Name Fission Type studio Artist Jens Johansson Cover Jens Johansson 1998 Fission.jpg Released 1998 Recorded Moon Path Alpha in Malm , Sweden Starec Grammophone in V xj , Sweden East Side Recorders in New York City , New York Big Noise Studios in New York City, New York Heptagon Remote in Andersl v , Sweden. Genre Jazz fusion , instrumental rock Length 68 39 Label Heptagon Producer Jens Johansson Reviews Allmusic Rating 4 5 Allmusic class album id r341774 pure url yes link Last album Sonic Winter br 1997 This album Fission br 1998 Next album The Last Viking br 1999 Misc Extra album cover Upper caption Alternative cover Type studio Cover Jens Johansson 1998 Fission alternative .jpg Lower caption United States edition Fission is a studio album by keyboardist Jens Johansson , released in 1998 through Heptagon Records Europe , Pony Canyon Pony Canyon, Inc. Japan and Shrapnel Records United States . Track listing tracklist all writing Jens Johansson title1 Hooded Strangers length1 10 41 title2 Phase Camouflage length2 6 49 title3 Zero Sum Game length3 3 36 title4 Acrostic Shibboleth length4 8 12 title5 Don t Mention the War length5 10 49 title6 Race Condition length6 7 32 title7 Crowd Tectonics length7 6 15 title8 Nystagmus length8 3 59 title9 Beautiful Lung Dogs length9 10 46 total length 68 39 Personnel Jens Johansson keyboard instrument keyboard , synthesizer Bass synthesizer bass synthesizer , record producer production Shawn Lane electric guitar tracks 1, 4 Mike Stern electric guitar tracks 2, 4, 6 Anders Johansson drum kit drums , percussion instrument percussion DEFAULTSORT Fission Album Category Jens Johansson albums Category 1998 albums ... more details
unreferenced date February 2008 Loop fission or loop distribution is a compiler optimization technique attempting to break a loop into multiple loops over the same index range but each taking only a part of the loop s body. The goal is to break down large loop body into smaller ones to achieve better utilization of locality of reference . It is the reverse action to loop fusion . This optimization is most efficient in multi core processors that can split a task into multiple tasks for each processor. border 1 cellpadding 1 Original loop After loop fission pre int i, a 100 , b 100 for i 0 i 100 i a i 1 b i 2 pre pre int i, a 100 , b 100 for i 0 i 100 i a i 1 for i 0 i 100 i b i 2 pre Further reading cite book author Kennedy, Ken & Allen, Randy. title Optimizing Compilers for Modern Architectures A Dependence based Approach publisher Morgan Kaufmann year 2001 isbn 1 55860 286 0 See also Loop transformation Category Compiler optimizations ... more details
wiktionarypar nuclear nucular Nuclear may refer to Atomic nucleus Nuclear engineering Nuclear energy Nuclear physics Nuclear power Nuclear reactor technology Nuclear weapon Cell nucleus Nuclear DNA In mathematics , a condition related to tensor product s in functional analysis Nuclear space Nuclear operator Nuclear C algebra See also Nucleus disambiguation Nucleolus Nucleation Nucleic acid Nuclear family lookfrom Nucleo lookfrom Nuclear disambig cleanup date March 2011 cy Niwclear id Nuklir pt Nuclear ro Nuclear simple Nuclear su Nuklir tl Nukleyar th ur ... more details
Infobox Book name Nuclear or Not? Does Nuclear Power Have a Place in a Sustainable Energy Future? title orig translator image Image 9780230507647 Nuclear Or Not cover.jpg image caption author David Elliott illustrator cover artist country language series subject genre publisher Palgrave Macmillan pub date 2007 english pub date media type pages isbn 9780230507647 dewey 333.792 40941 22 congress HD9698.G72 N84 2007 oclc 71812857 preceded by followed by Nuclear or Not? Does Nuclear Power Have a Place in a Sustainable Energy Future? is a 2007 book edited by Professor David Elliott professor David Elliott . The book offers various views and perspectives on nuclear power . ref name nuc http www.no2nuclearpower.org.uk reviews review02.php Nuclear or Not? Does Nuclear Power Have a Place in a Sustainable Energy Future? Edited by David Elliott. Palgrave Macmillan, 2007. ISBN 978 0 230 50764 7. Review by No2NuclearPower ref Authors include Paul Allen from the Centre for Alternative Technology Dr Ian Fairlie, who served on the Committee Examining Radiation Risks of Internal Emitters CERRIE Stephen Kidd of the World Nuclear Association ref name nuc Professor Elliott calls for continued debate on the nuclear power issue. He has worked with the United Kingdom Atomic Energy Authority before moving to the Open University where he is Professor of Technology Policy and has developed courses on technological innovation, focusing in particular on renewable energy technology. ref name dav http design.open.ac.uk ... products title.aspx?is 0230507646 Nuclear Or Not? Description at publisher s site ref See also List of books about nuclear issues Nuclear Power and the Environment Reaction Time book References references External links http oro.open.ac.uk 3940 Non nuclear sustainable energy futures for Germany and the UK Category Nuclear power Category Environmental non fiction books Category 2007 books Category British non fiction books Category Books about nuclear issues simple Nuclear or Not? ... more details
Empty section date July 2010 External links DEFAULTSORT Fission Fragment Reactor Category Nuclear ...Unreferenced date December 2009 Similar to how the fission fragment rocket produces thrust, a fission fragment reactor is a nuclear reactor that generates electricity by decelerating an ion beam of Nuclearfissionfission byproducts instead of using nuclear reactions to generate heat . By doing so, it bypasses the Carnot cycle and can achieve efficiencies of up to 90 instead of 40 45 attainable by efficient turbine driven thermal reactors. Fission fragment reactor designs generally have several common components. The reactor chamber contains a high surface area nuclear fuel to both facilitate direct emission of fission fragments and assist in cooling the fuel. Generally, if fuels subject to criticality are used instead of those that naturally radioactive decay decay as in a nuclear battery , a neutron moderator moderator is typically involved as well. A magnetic mirror induced by an axial magnetic field typically collates the fragments into a beam that can then be decelerated to electricity generation generate power . The rate the particles decelerate at depends on their energy as a consequence, the deceleration process also can help provide isotopic separation as an automatic nuclear reprocessing reprocessing stage. An earlier design by scientists at Idaho National Engineering Laboratory and Lawrence Livermore National Laboratory involved the concept of coating fine carbon wires with fissionable fuel. While this had a high surface area, it proved not enough to radiate the heat absorbed during the reactions, so their design was modified to rotate long wires through the core, giving them time to cool. A later design by Rodney A. Clark and Robert B. Sheldon involves the use of a dusty plasma of electrostatic ally suspended fuel nanoparticle s in the core. This increases the surface area enough to allow for effective radiative cooling. As the particles naturally ionize as fission ... more details
Long lived fission products are radioactive materials with a long half life more than 200,000 years produced by nuclearfission . Evolution of radioactivity in nuclear waste Nuclearfission produces fission products , as well as actinide s from nuclear fuel nuclei that capture neutrons but fail to fission ... term The high short term radioactivity of spent nuclear fuel is primarily from fission products with short half life . The radioactivity in the fission product mixture is mostly short lived isotopes such as Iodine ... an open air nuclear detonation where all the fission products are dispersed. Medium lived fission products Medium lived fission products After several years of cooling, most radioactivity is from the fission ... lived fission product s. ref cite book title Nuclear Wastes Technologies for Separations and Transmutation url http books.google.com books?id iRI7Cx2D4e4C&pg PA23&lpg PA23&dq 22medium lived fission products ... half lives of about 30 years. Other fission products with similar half lives have much lower fission ... year 1996 publisher National Academies Press ref ref cite web title The Nuclear Alchemy Gamble An Assessment of Transmutation as a Nuclear Waste Management Strategy url http www.ieer.org reports transm ... nuclear reprocessing however, its inertness means that it does not concentrate in the environment ... levels, the bulk of radioactivity from spent fuel is from not fission products but actinides , notably ... be recovered by nuclear reprocessing either before or after most Cs 137 and Sr 90 decay and fissioned ... reactor s. Long lived fission products On scales greater than 10 sup 5 sup years, fission ... have not been destroyed. The most abundant long lived fission products have total decay energy around ... 4 5 MeV. Only seven fission products have long half lives, and these are much longer than 30 years, in the range of 200,000 to 16 million years. These are known as long lived fission products LLFP . Two ... 98 and samarium 146 that are shadowed from beta decay and can only occur as direct fission products ... more details
Image Fission fragment propulsion.svg 250px thumb right Fission fragment propulsion concept br a fissionable filaments, b revolving disks, br c reactor core, d fragments exhaust The fission fragment rocket is a rocket engine design that directly harnesses hot nuclearfission product s for thrust , as opposed ... of a fission fragment rocket at the same time over the bundle proposal. ref Clark, R. Sheldon, R. http www.rbsp.info rbs RbS PDF aiaa05.pdf Dusty Plasma Based Fission Fragment Nuclear Reactor American ... In traditional nuclear thermal rocket and related designs, the nuclear energy is generated in some ... is not actually reacting at any given instance. In fact the atoms undergoing fission are at a temperature ... temperature of a few thousand. In the fission fragment design, it is the individual atoms that actually undergo fission that are used to provide thrust, by extracting them from the rest of the fuel ... layers of a fuel bundle will be most likely to undergo fission, the high temperature atoms, the fragments of a nuclear reaction, can boil off the surface. Since they will be ionized due to the high temperatures ... 400px right thumb Dusty plasma bed reactor br A fission fragments ejected for propulsion br B reactor br C fission fragments decelerated for power generation br d moderator BeO or LiH , e containment ... was placed into a number of very thin carbon bundles, each one normally sub Critical mass nuclear ... critical. The fission fragments at the surface of the bundles would break free and be channeled for thrust ... performance of the fission fragment system lower. Nonetheless, the system provides the sort ... ionization ionize as fission occurs, the dust becomes suspended within the chamber ... should be able to achieve over 1,000,000 sec Specific Impulse I sub sp sub . See also Fission fragment reactor References references clr spacecraft propulsion Nuclear propulsion Category Nuclear spacecraft propulsion fr Propulsion par fragments de fission ... more details
Fission track dating is a radiometric dating technique based on analyses of the damage trails, or tracks, left by Nuclearfissionfission fragments in certain uranium bearing mineral s and glass es. ref cite book author R.L. Fleischer coauthors P. B. Price, and R. M. Walker title Nuclear Tracks in Solids publisher University of California Press , Berkeley date 1975 ref Fission track dating is a relatively ... of different Archaeology archeological artifacts. The method involves using the number of fission ... of rock cooling below closure temperature . Fission tracks are sensitive to heat, and therefore ... using fission tracks is aimed at a understanding the evolution of mountain belts b determining ... artifacts. Method Unlike other isotopic dating methods, the Decay product daughter in fission ... fission decay at a known rate, and it is the only isotope with a decay rate that is relevant to the significant production of natural fission tracks other isotopes have fission decay rates too slow to be of consequence. The fragments emitted by this fission process leave trails of damage fossil ... etching of polished internal surfaces of these minerals reveals spontaneous fission tracks, and the track ... with thermal neutrons in a nuclear reactor, with an external detector, such as mica , affixed to the grain surface. The neutron irradiation induces fission of uranium 235 in the sample, and the resulting ... 235 U 238 ratio is well known and assumed constant in nature. To determine the number of induced fission ... induced fission of the uranium 235 in the sample creates induced tracks in the overlying external ... through a mass spectrometer . Applications Unlike many other dating techniques, fission track dating ... uranium epidote s and garnet s may be used for very old samples Paleozoic to Precambrian . The fission ... in mountain belts. Fission tracks are preserved in a crystal when the ambient temperature ... causes the fission damage to heal or anneal, the technique is useful for dating the most recent ... more details
Nucleon pair breaking in fission has been an important topic in nuclear physics for decades. The most measured quantities in research on nuclearfission are the charge and mass fragments yields for uranium 235 and other transuranics. In this sense, experimental results on charge distribution for low energy fission of actinides present a preference to even Z fragment, which is called odd even effect on charge yield ref http prola.aps.org abstract PRL v34 i16 p1034 1 G. Siegert et al. . Nuclear Charge Distributions in the Isobars 92 to 100 Resulting from Thermal Neutron Fission of Uranium 235 , Physical Review Letters , American Physical Society, Volume 34, No 16 1975, DOI 10.1103 PhysRevLett.34.1034, pp. 1034 1036 ref . The importance of these distributions is because they are the result of rearrangement of nucleons on the fission process due to the interplay between collective variables and individual particle levels therefore they permit to understand several aspects of dynamics of fission process. The process from saddle when nucleus begins its irreversible evolution to fragmentation to scission point when fragments are formed and nuclear interaction between fragments dispels , fissioning system shape changes but also promote nucleons to excited particle levels. Because, for even Z proton number and even N neutron number nuclei, there is a gap from ground state to first excited particle state which is reached by nucleon pair breaking , fragments with even Z is expected to have a higher probability to be produced than those with odd Z. The preference even Z even N divisions ... by the hypothesis that in fission process always there will be nucleon pair breaking, which may be proton pair o neutron pair breaking in low energy fission of uranium 234, uranium 236, ref http hal.archives ... and kinetic energy distribution in cold fission of sup 233 sup U, sup 235 sup U and sup 239 sup Pu induced ..., Vol 319, No 2 June, 1984, DOI 10.1007 BF01415636, pp. 219 225 ref References Reflist Category Fission ... more details
main Fission product Long lived fission products Nuclearfission splits a heavy nucleus such as uranium or plutonium into two lighter nuclei, which are called fission products . Yield refers to the fraction of a fission product produced per fission. Yield can be broken down by Individual isotope Chemical .... In general, the higher the energy of the state that undergoes nuclearfission, the more likely ... neutron poison fission products, from thermal neutron fission of Uranium 235 U 235 typical of nuclear ... chain of beta decay . Isotope and element yields will change as the fission products undergo beta decay ... fission products delayed neutron s , with halflife measured in seconds. A few isotopes can be produced directly by fission, but not by beta decay because the would be precursor with atomic number ..., they have very low yields less than a millionth as much as common fission products because they are far ... per fission, so that the total yield percentages sum to 200 . Less often, it is stated as percentage of all fission products, so that the percentages sum to 100 . Medium lived fission products Mass vs. yield curve Image fission yield volatile.png thumb 450px From Fluoride volatility Blue elements have ... sup 0,1,2,3 sup years after fission , not considering later neutron capture , fraction of 100 not 200 ... ThermalFissionYield.svg thumb 450px Fission product yields by mass for thermal neutron fission of U 235, Pu 239, a combination of the two typical of current nuclear power reactors, and U 233 used in the thorium cycle If a graph of the mass or Mole unit mole yield of fission products against the atomic ... and one at xenon through to neodymium . This is because the fission event causes the nucleus ... Yield vs. Z This is a typical distribution for the fission of uranium . Note that in the calculations used to make this graph the activation of fission products was ignored and the fission was assumed ... cooling times time after fission . Because of the stability of nuclei with even numbers of proton ... more details
On this page, a discussion of each of the main elements in the fission product mixture from the nuclearfission of an actinide such as uranium or plutonium is set out by element. Medium lived fission products Long lived fission products Krypton 83 86 isotope colour chart Iso1 83 Kr R Iso1 84 Kr R Iso2 Kr 85 85 Kr G Iso1 86 Kr R Krypton 85 is formed by the fission process with a fission yield of about 0.3 . Only 20 of the fission products of mass 85 become sup 85 sup Kr itself the rest passes through a short lived nuclear isomer and then to stable sup 85 sup Rb. If irradiated reactor fuel is nuclear ... fission product page for further details of caesium as a troublesome isotope in fall out and nuclear ... the natural nuclearfission reactor operated millions of years ago the isotopic mixture of neodymium ... which underwent fission . Category Nuclear technology Category Nuclear chemistry Category Nuclear ... can be detected and used as a means of detecting clandestine nuclear reprocessing. Strictly speaking, the stage which is detected is the dissolution of used nuclear fuel in nitric acid , as it is at this stage that the krypton and other fission gases like the more abundant xenon are released. Increase of fission gases above a certain limit can lead to fuel pin swelling and even puncture, so that fission ... of 28.8 years. Its fission product yield decreases as the mass of the fissile nuclide increases. A map ... Y I The only stable yttrium isotope, sup 89 sup Y, will be found with yield somewhat less than 1 in a fission ... 95 Zr I Iso1 96 Zr O A significant amount of zirconium is formed by the fission process some of this are short ... almost 10 of the fission products mixture after years of decay consists of five stable or nearly stable ... is one of the 7 major long lived fission product s. In PUREX plants the zirconium sometimes forms ... 98 Mo R Iso1 99 Mo V Iso1 100 Mo O The fission product mixture contains significant amounts of molybdenum ... 6 per fission see also the main fission product s page. Ruthenium 101 106 Iso1 101 Ru R Iso1 102 Ru ... more details
File SAFE 30 Reactor.png thumb SAFE 30 small experimental reactor Safe Affordable Fission Engine SAFE are NASA s small experimental nuclearfission reactor s for electricity production in space. Most known is the SAFE 400 reactor producing 400 kW thermal power, giving 100 kW of electric energy using a Brayton cycle gas turbine. The fuel is uranium nitride in a core of 381 pins clad with rhenium . Three fuel pins surround a molybdenum sodium heatpipe that transports the heat to a heatpipe gas heat exchanger . This is called a Heatpipe Power System . ref name Poston cite conference first Poston last David I. coauthors Richard J. Kapernick and Ray M. Guffee year 2002 month title Design and analysis of the SAFE 400 space fission reactor conference conferenceurl booktitle Space Technology and Applications International Forum STAIF 2002 editor ohamed S. El Genk and Mary J. Bragg volume 608 publisher AIP pages 578 588 doi 10.1063 1.1449775 ref ref name Blanchard cite conference first James P. last Blanchard title Stretching the Boundaries of Nuclear Technology booktitle Eighth Annual Symposium on Frontiers of Engineering Reports on Leading Edge Engineering from the 2002 NAE Symposium on Frontiers of Engineering pages 84 publisher National Academies Press date 2003 url http books.google.com books?id lmL5PYXsS8cC&pg PA84 accessdate 2009 02 24 id ISBN 0309087325 Also at http www.nae.edu nae bridgecom.nsf weblinks MKEZ 5HUQ7J?OpenDocument nae.edu ref The reactor is about convert ... Poonawala cite news url http www.dawn.com weekly science archive 040724 science6.htm title Nuclear ... 7b vandy.pdf title The Safe Affordable Fission Engine SAFE Test Series last Poston first David coauthors ... nuclear rockets to reach deep space last Spotts first Peter N. date 2002 02 28 work The Christian Science Monitor accessdate 2009 02 24 ref See also Systems Nuclear Auxiliary Power Program and SNAP 10A , that flew in 1965 SP 100 References reflist Category Nuclear power in space ... more details
Image Gun type fission weapon en labels thin lines.svg 360px right thumb The gun assembly method. Gun type fission weapons are nuclearfissionfission based nuclear weapons whose nuclear weapon design design assembles their fissile material into a Critical mass nuclear supercritical mass by the use of the gun ... is relatively large, and the Nuclear weapon design Efficiency efficiency relatively low. The method ... and several additional units of the same design prepared after World War 2, in 40 Mark 8 nuclear bomb Mark 8 bombs, and their replacement, 40 Mark 11 nuclear bomb Mark 11 bombs. The second was a family of 11 inch nuclear artillery shells, the W9 nuclear warhead W9 and its derivative W19 nuclear ... nuclear artillery shell W23 . The third family was an 8 inch artillery shell, the W33 nuclear weapon W33 . Last, South Africa also developed a handful 8 of nuclear bombs based on the gun type ... of mass destruction Nuclear weapons . There are currently no known gun type weapons in service advanced nuclear weapon states tended to abandon the design in favor of the Nuclear weapon design Implosion type weapon implosion type weapon, and new nuclear weapon states tend to develop implosion type weapons only. All known gun type nuclear weapons previously built worldwide have been dismantled ... place before the material could be fully joined see nuclear chain reaction . Note that typically ... happens in a time so short that the bullet hardly moves in that time. This could cause a fizzle , a Nuclear ... barrel. In the case of Little Boy, the 20 U 238 in the uranium had 70 spontaneous fission s per second ... each fission creates on average 2.52 neutrons, which each have a probability of more than 1 2.52 of creating another fission. During the 1.35 ms of supercriticality prior to full assembly, there was a 10 probability of a fission, with somewhat less probability of pre detonation. Image Thin Man plutonium ... type bomb Thin Man nuclear bomb Thin Man , shown above and focused almost entirely around the problem ... more details
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