999:. In this technique, a thin uranium target is bombarded with protons and nuclear reaction products recoil out of the target in a charged state. The recoils are stopped in a gas cell and then exit through a small hole in the side of the cell where they are accelerated electrostatically and injected into a mass separator. This method of production and extraction takes place on a shorter timescale compared to the standard ISOL technique and isotopes with short half-lives (sub millisecond) can be studied using an IGISOL. An IGISOL has also been combined with a laser ion source at the Leuven Isotope Separator On Line (LISOL) in Belgium. Thin target sources generally provide significantly lower quantities of radioactive ions than thick target sources and this is their main drawback.
483:
342:
420:
829:) distillation was developed in the late 1960s by scientists at Los Alamos National Laboratory. It is still the preferred method forC enrichment. Deuterium enrichment by water distillation is only done, if it was preenriched by a process (chemical exchange) with lower energy demand. Beginning with the low natural abundance (0.015% D) would require evaporation of too large quantities of water.
566:). This method has only been developed as laser technology has improved in the 1970s to 1980s. Attempts to develop it to an industrial scale for uranium enrichment were successively given up in the 1990s "due to never ending technical difficulties" and because centrifuges have reached technical maturity in the meantime. However, it is a major concern to those in the field of
525:. After the war the method was largely abandoned as impractical. It had only been undertaken (along with diffusion and other technologies) to guarantee there would be enough material for use, whatever the cost. Its main eventual contribution to the war effort was to further concentrate material from the gaseous diffusion plants to higher levels of purity.
276:, a strong alpha emitter that poses self-heating and radiotoxicity problems. Therefore, the uranium targets used to produce military plutonium must be irradiated for only a short time, to minimise the production of these unwanted isotopes. Conversely, blending plutonium with Pu-240 renders it less suitable for nuclear weapons.
470:. The gas is injected tangentially into a chamber with special geometry that further increases its rotation to a very high rate, causing the isotopes to separate. The method is simple because vortex tubes have no moving parts, but energy intensive, about 50 times greater than gas centrifuges. A similar process, known as
394:
was a US government effort to generate highly enriched uranium to power military reactors and create nuclear bombs which led to the establishment of the facility in 1952. Paducah's enrichment was initially kept to low levels, and the facility operated as a "feed facility" for other defence facilities
252:
The only alternative to isotope separation is to manufacture the required isotope in its pure form. This may be done by irradiation of a suitable target, but care is needed in target selection and other factors to ensure that only the required isotope of the element of interest is produced. Isotopes
163:
All large-scale isotope separation schemes employ a number of similar stages which produce successively higher concentrations of the desired isotope. Each stage enriches the product of the previous step further before being sent to the next stage. Similarly, the tailings from each stage are returned
976:
Once purified isobarically, the ion beam is then sent to the individual experiments. In order to increase the purity of the isobaric beam, laser ionization can take place inside the ionizer cavity to selectively ionize a single element chain of interest. At CERN, this device is called the
Resonance
952:
Radioactive beams of specific isotopes are widely used in the fields of experimental physics, biology and materials science. The production and formation of these radioactive atoms into an ionic beam for study is an entire field of research carried out at many laboratories throughout the world. The
446:
The centrifugal separation of isotopes was first suggested by Aston and
Lindemann in 1919 and the first successful experiments were reported by Beams and Haynes on isotopes of chlorine in 1936. However attempts to use the technology during the Manhattan Project were unproductive. In modern times it
972:
effect). Once ionized, the radioactive species are accelerated by an electrostatic field and injected into an electromagnetic separator. As ions entering the separator are of approximately equal energy, those ions with a smaller mass will be deflected by the magnetic field by a greater amount than
501:
and the amount of deflection depends upon the particle's mass. It is very expensive for the quantity produced, as it has an extremely low throughput, but it can allow very high purities to be achieved. This method is often used for processing small amounts of pure isotopes for research or specific
1002:
As experimental nuclear physics progresses, it is becoming more and more important to study the most exotic of radioactive nuclei. In order to do so, more inventive techniques are required to create nuclei with extreme proton/neutron ratios. An alternative to the ISOL techniques described here is
990:
metals such as tungsten and rhenium do not emerge from the target even at high temperatures due to their low vapour pressure. In order to produce these types of beams, a thin target is required. The Ion Guide
Isotope Separator On Line (IGISOL) technique was developed in 1981 at the University of
644:
is selectively excited by an infrared laser near 16 μm. In contrast to the excited molecules, the nonexcited heavier isotopic molecules tends to form clusters with the carrier gas, and these clusters stay closer to the axis of the molecular beam, so that they can pass a skimmer and are thus
455:
Use of gaseous centrifugal technology to enrich isotopes is desirable as power consumption is greatly reduced when compared to more conventional techniques such as diffusion plants since fewer cascade steps are required to reach similar degrees of separation. As well as requiring less energy to
353:
method relies on the fact that in thermal equilibrium, two isotopes with the same energy will have different average velocities. The lighter atoms (or the molecules containing them) will travel more quickly through a membrane, whose pore diameters are not larger than the mean free path length
960:
is ISOLDE at CERN, which is a joint
European facility spread across the Franco-Swiss border near the city of Geneva. This laboratory uses mainly proton spallation of uranium carbide targets to produce a wide range of radioactive fission fragments that are not found naturally on earth. During
438:
can separate isotopes as well as separating ranges of elements for radioactive waste reduction, nuclear reprocessing, and other purposes. The process is called "plasma mass separation"; the devices are called "plasma mass filter" or "plasma centrifuge" (not to be confused with
386:
gas as the process fluid. Nickel powder and electro-deposited nickel mesh diffusion barriers were pioneered by Edward Adler and Edward Norris. Due to the high energy consumption, enrichment of uranium by diffusion was gradually replaced by more efficient methods.
806:, which in turn results from its lower energy of zero-point vibration in the intermolecular potential. As expected from formulas for vapor pressure, the ratio becomes more favorable at lower temperatures (lower pressures). The vapor pressure ratio for H
451:
gas is connected to a cylinder that is rotated at high speed. Near the outer edge of the cylinder heavier gas molecules containing U-238 collect, while molecules containing U-235 concentrate at the centre and are then fed to another cascade stage.
456:
achieve the same separation, far smaller scale plants are possible, making them an economic possibility for a small nation attempting to produce a nuclear weapon. Pakistan is believed to have used this method in developing its nuclear weapons.
311:
reactors. Obtaining heavy water however also requires isotope separation, in this case of hydrogen isotopes, which is easier due to the bigger variation in atomic weight. Both magnox and RBMK reactors had undesirable properties when run with
953:
first isotope separator was developed at the
Copenhagen Cyclotron by Bohr and coworkers using the principle of electromagnetic separation. Today, there are many laboratories around the world that supply beams of radioactive ions for use.
620:
Several alternative MLIS schemes have been developed. For example, one uses a first laser in the near-infrared or visible region, where a selectivity of over 20:1 can be obtained in a single stage. This method is called OP-IRMPD (Overtone
126:
The third type of separation is still experimental; practical separation techniques all depend in some way on the atomic mass. It is therefore generally easier to separate isotopes with a larger relative mass difference. For example,
798:
of the column and is multiplied by the same factor in the next step (at the next plate). Because the elementary separation factor is small, a large number of such plates is needed. This requires total column heights of 20 to 300 m.
985:
As the production of radioactive atoms by the ISOL technique depends on the free atom chemistry of the element to be studied, there are certain beams which cannot be produced by simple proton bombardment of thick actinide targets.
625:). But due to the small absorption probability in the overtones, too many photons remain unused, so that the method did not reach industrial feasibility. Also some other MLIS methods suffer from wasting of the expensive photons.
1003:
that of fragmentation beams, where the radioactive ions are produced by fragmentation reactions on a fast beam of stable ions impinging on a thin target (usually of beryllium atoms). This technique is used, for example, at the
366:
it is 1.0043. Hence many cascaded stages are needed to obtain high purity. This method is expensive due to the work needed to push gas through a membrane and the many stages necessary, each requiring recompression of the gas.
243:
Isotope separation is an important process for both peaceful and military nuclear technology, and therefore the capability that a nation has for isotope separation is of extreme interest to the intelligence community.
180:
To date, large-scale commercial isotope separation of only three elements has occurred. In each case, the rarer of the two most common isotopes of an element has been concentrated for use in nuclear technology:
660:
electron and nucleus mass which with the same field frequency further leads to excitation of Trojan or anti-Trojan wavepacket depending on the kind of the isotope. Those and their giant, rotating
851:, and it measures the quantity of separative work (indicative of energy used in enrichment) when feed and product quantities are expressed in kilograms. The effort expended in separating a mass
447:
is the main method used throughout the world to enrich uranium and as a result remains a fairly secretive process, hindering a more widespread uptake of the technology. In general a feed of UF
961:
spallation (bombardment with high energy protons), a uranium carbide target is heated to several thousand degrees so that radioactive atoms produced in the nuclear reaction are released.
537:
is tuned to a wavelength which excites only one isotope of the material and ionizes those atoms preferentially. For atoms, the resonant absorption of light for an isotope depends on
411:. The goal of Paducah and its sister facility in Piketon was adjusted in the 1960s when they started to enrich uranium for use in commercial nuclear reactors to produce energy.
944:
If, for example, for 100 kilograms (220 pounds) of natural uranium, it takes about 60 SWU to produce 10 kilograms (22 pounds) of uranium enriched in U-235 content to 4.5%.
328:
in particular relies on heavy water moderated reactors for its nuclear power. A big downside of heavy water reactors is the enormous upfront cost of the heavy water.
682:
1004:
964:
Once out of the target, the vapour of radioactive atoms travels to an ionizer cavity. This ionizer cavity is a thin tube made of a refractory metal with a high
814:
O is 1.055 at 50 °C (123 mbar) and 1.026 at 100 °C (1013 mbar). For CO to CO it is 1.007 near the normal boiling point (81.6 K), and 1.003 for CH
1670:
61:
is the largest application. In the following text, mainly uranium enrichment is considered. This process is crucial in the manufacture of uranium fuel for
617:
before being introduced into the next MLIS stage. But with light elements, the isotope selectivity is usually good enough that cascading is not required.
1601:
1220:
629:
232:
Some isotopically purified elements are used in smaller quantities for specialist applications, especially in the semiconductor industry, where purified
636:
in
Australia, has been licensed to General Electric for the development of a pilot enrichment plant. For uranium, it uses a cold molecular beam with UF
474:
was created in
Germany, with a demonstration plant built in Brazil, and they went as far as developing a site to fuel the country's nuclear plants.
430:
schemes rapidly rotate the material allowing the heavier isotopes to go closer to an outer radial wall. This is often done in gaseous form using a
88:, isotopes of the same element have nearly identical chemical properties which makes this type of separation impractical, except for separation of
216:
is both a nuisance in the coolant / moderator of water moderated reactors and a valuable product; it is thus sometimes separated from the coolant.
696:
Although isotopes of a single element are normally described as having the same chemical properties, this is not strictly true. In particular,
1643:
1480:
1095:
977:
Ionization Laser Ion Source (RILIS). Currently over 60% of all experiments opt to use the RILIS to increase the purity of radioactive beams.
563:
558:
allowing finely tuned lasers to interact with only one isotope. After the atom is ionized it can be removed from the sample by applying an
586:
510:
404:
794:. The separation factor is the ratio of vapor pressures of two isotopic molecules. In equilibrium such a separation results at each
622:
598:
467:
497:
on a large scale, so it is sometimes referred to as mass spectrometry. It uses the fact that charged particles are deflected in a
358:). The speed ratio is equal to the inverse square root of the mass ratio, so the amount of separation is small. For example for UF
316:, which ultimately led to the replacement of this fuel with low enriched uranium, negating the advantage of foregoing enrichment.
1504:
1008:
279:
If the desired goal is not an atom bomb but running a nuclear power plant, the alternative to enrichment of uranium for use in a
482:
77:
produced in a nuclear reactor, which must be operated in such a way as to produce plutonium already of suitable isotopic mix or
391:
317:
716:
165:
1529:
609:
which then precipitates out of the gas. Cascading the MLIS stages is more difficult than with other methods because the UF
396:
685:
1649:
840:(SWU) is a complex unit which is a function of the amount of uranium processed and the degree to which it is enriched,
1685:
1657:
1131:
1301:
Whitley, Stanley (1984-01-01). "Review of the gas centrifuge until 1962. Part I: Principles of separation physics".
790:
Isotopes of hydrogen, carbon, oxygen, and nitrogen can be enriched by distilling suitable light compounds over long
1690:
300:
119:
1665:
545:
375:
341:
973:
those with a heavier mass. This differing radius of curvature allows for isobaric purification to take place.
325:
1605:
715:
for details. Lighter isotopes also disassociate more rapidly under an electric field. This process in a large
703:
Techniques using this are most effective for light atoms such as hydrogen. Lighter isotopes tend to react or
712:
684:-shifted in phase and the beam of such atoms splits in the gradient of the electric field in the analogy to
152:
1471:
B.M. Andreev; E.P.Magomedbekov; A.A. Raitman; M.B.Pozenkevich; Yu.A. Sakharovsky; A.V. Khoroshilov (2007).
172:, which is a number greater than 1. The second is the number of required stages to get the desired purity.
803:
727:
661:
321:
1375:
1626:
1224:
606:
567:
440:
431:
1671:
Annotated bibliography on electromagnetic separation of uranium isotopes form the Alsos
Digital Library
169:
264:
Pu-239 is produced following neutron capture by uranium-238, but further neutron capture will produce
1310:
1267:
1170:
837:
791:
590:
400:
383:
237:
225:
49:
where atoms of "marker" nuclide are used to figure out reaction mechanisms). By tonnage, separating
871:
is expressed in terms of the number of separative work units needed, given by the expression SWU =
633:
551:
355:
280:
168:. There are two important factors that characterize the performance of a cascade. The first is the
62:
1376:"The Laser Isotope Separation Program at Lawrence Livermore Laboratory.: Laser Isotope Separation"
1052:
652:
separation using Trojan wavepackets in circularly polarized electromagnetic field. The process of
164:
to the previous stage for further processing. This creates a sequential enriching system called a
1403:
1202:
1161:
969:
653:
514:
324:
which has limited domestic uranium resources and been under a partial nuclear embargo ever since
370:
The first large-scale separation of uranium isotopes was achieved by the United States in large
1486:
1476:
1437:
1395:
1361:"Uranium enrichment by jet nozzle separation process in the German-Brazil cooperation program"
1360:
1326:
1283:
1194:
1186:
1091:
1087:
795:
518:
494:
427:
379:
371:
288:
284:
240:, and carbon with greater isotopic purity to make diamonds with greater thermal conductivity.
85:
1345:
570:, because it may be cheaper and more easily hidden than other methods of isotope separation.
1554:
Miller, Alistair I. (2001). "Heavy Water: A Manufacturers' Guide for the
Hydrogen Century".
1387:
1318:
1275:
1240:
1178:
844:
the extent of increase in the concentration of the U-235 isotope relative to the remainder.
435:
189:
58:
54:
38:
1661:
667:
503:
313:
197:
193:
50:
17:
1314:
1271:
1258:
Beams, J. W.; Haynes, F. B. (1936-09-01). "The
Separation of Isotopes by Centrifuging".
1174:
1391:
968:
allowing for collisions with the walls to liberate a single electron from a free atom (
826:
559:
498:
419:
253:
of other elements are not so great a problem as they can be removed by chemical means.
228:. Tritium is commonly produced from lithium-6 which is often enriched for this purpose.
66:
1508:
1679:
1206:
1080:
965:
730:
ever measured at room temperature, 305, may eventually be used for the separation of
697:
571:
408:
257:
148:
144:
112:
105:
1407:
1452:
and L.W. Hillman (Eds.), Dye Laser Principles (Academic, New York, 1990) Chapter 9.
1449:
657:
463:
260:
for use in weapons. It is not practical to separate Pu-239 from Pu-240 or Pu-241.
708:
704:
594:
579:
459:
292:
207:
140:
136:
70:
1533:
1155:
Zweben, Stewart J.; Gueroult, Renaud; Fisch, Nathaniel J. (12 September 2018).
656:
formation by the adiabatic-rapid passage depends in ultra-sensitive way on the
1461:
F. J. Duarte (Ed.), Tunable Laser Applications, 2nd Ed. (CRC, 2008) Chapter 11
1244:
987:
1490:
1399:
1330:
1322:
1287:
1190:
707:
more quickly than heavy isotopes, allowing them to be separated. This is how
593:
gas (if enrichment of uranium is desired), exciting molecules that contain a
1425:
992:
649:
575:
350:
221:
128:
89:
74:
46:
1654:
1279:
118:
Those based on properties not directly connected to atomic weight, such as
602:
522:
517:
developed electromagnetic separation for much of the uranium used in the
487:
268:
which is less fissile and worse, is a fairly strong neutron emitter, and
203:
132:
42:
1121:
nuclear.org/info/Country-Profiles/Countries-T-Z/USA--Nuclear-Fuel-Cycle/
926:
Separative work is expressed in SWUs, kg SW, or kg UTA (from the German
1644:
Utilization of kinetic isotope effects for the concentration of tritium
1530:"Laboratory alliance to put "Made in America" stamp on stable isotopes"
996:
735:
731:
261:
233:
213:
185:
34:
1198:
1182:
1156:
802:
The lower vapor pressure of the heavier molecule is due to its higher
720:
304:
273:
269:
265:
45:
produced is varied. The largest variety is used in research (e.g. in
1228:
1032:
Garwin, Richard L. (Nov 1997). "The Technology of Nuclear Weapons".
1012:
534:
481:
418:
340:
296:
308:
554:
splitting of electronic transitions, if the nucleus has a spin,
256:
This is particularly relevant in the preparation of high-grade
423:
A cascade of gas centrifuges at a US uranium enrichment plant.
345:
Gaseous diffusion uses microporous membranes to enrich uranium
1507:. Los Alamos National Laboratory. Winter 2003. Archived from
1587:
648:
Quite recently yet another scheme has been proposed for the
1438:
https://inis.iaea.org/search/search.aspx?orig_q=rn:27014297
1117:
World Nuclear Association, US Nuclear Fuel Cycle, (2015),
589:(MLIS). In this method, an infrared laser is directed at
151:, while desirable in that it would allow the creation of
135:
and it is generally easier to purify it than to separate
541:
the nuclear mass (noticeable mainly with light elements)
100:
There are three types of isotope separation techniques:
1573:
155:
from plutonium, is generally agreed to be impractical.
65:
and is also required for the creation of uranium-based
1436:
Schneider, K. R., LIS: the view from Urenco (1995). (
670:
486:
Schematic diagram of uranium isotope separation in a
27:
Concentrating specific isotopes of a chemical element
1424:. (PDF) Max-Planck-Institut für Quantenoptik, 2015,
1118:
287:with a lower neutron absorption cross section than
1079:
676:
349:Often done with gases, but also with liquids, the
1053:"AMD tests 'super silicon' to beat heat problems"
544:the nuclear volume (causing a deviation from the
111:Those based on the small differences in chemical
1422:Laser isotope separation and proliferation risks
734:(T). The effects for the oxidation of tritiated
719:was used at the heavy water production plant at
585:A second method of laser separation is known as
84:While chemical elements can be purified through
1266:(5). American Physical Society (APS): 491–492.
1007:(NSCL) at Michigan State University and at the
1346:"The Helikon technique for isotope enrichment"
320:such as the CANDU are still in active use and
143:. On the other extreme, separation of fissile
1374:Stern, R. C.; Snavely, B. B. (January 1976).
1309:(1). American Physical Society (APS): 41–66.
1005:National Superconducting Cyclotron Laboratory
597:atom. A second laser, either also in the IR (
562:. This method is often abbreviated as AVLIS (
390:The last diffusion plant closed in 2013. The
8:
645:separated from the excited lighter isotope.
509:At Oak Ridge National Laboratory and at the
210:for use as a moderator in nuclear reactors.
1473:Separation of isotopes of biogenic elements
700:are very slightly affected by atomic mass.
41:by removing other isotopes. The use of the
1380:Annals of the New York Academy of Sciences
630:Separation of isotopes by laser excitation
1426:https://www.mpq.mpg.de/5178012/MPQ346.pdf
669:
506:) but is impractical for industrial use.
236:is used to improve crystal structure and
33:is the process of concentrating specific
1229:"The possibility of separating isotopes"
521:. Devices using his principle are named
378:, which were established as part of the
206:isotopes have been separated to prepare
188:isotopes have been separated to prepare
1024:
395:that processed the enriched uranium at
131:has twice the mass of ordinary (light)
903:) is the "value function," defined as
863:of product assay xp and waste of mass
73:is used). Plutonium-based weapons use
934:1 SWU = 1 kg SW = 1 kg UTA
564:atomic vapor laser isotope separation
115:produced by different atomic weights.
7:
1604:(in Finnish). Jyu.fi. Archived from
1051:Thomas, Andrew (November 30, 2000).
822:near 111.7 K (boiling point).
1646:, GM Brown, TJ Meyer et al., 2001.
1505:"Spotlight Los Alamos in the News"
1392:10.1111/j.1749-6632.1976.tb41598.x
587:molecular laser isotope separation
548:, noticeable for heavier elements)
511:University of California, Berkeley
405:Portsmouth Gaseous Diffusion Plant
25:
1556:Canadian Nuclear Society Bulletin
640:in a carrier gas, in which the UF
599:infrared multiphoton dissociation
468:Helikon vortex separation process
224:has been concentrated for use in
1086:. Simon & Schuster. p.
1009:Radioactive Isotope Beam Factory
958:Isotope Separator On Line (ISOL)
738:anions to HTO were measured as:
632:' (SILEX) process, developed by
318:Pressurized heavy-water reactors
948:Isotope separators for research
623:IR Multiple Photon Dissociation
392:Paducah Gaseous Diffusion Plant
1040:(8): 6–7 – via Proquest.
726:One candidate for the largest
711:is produced commercially, see
613:must be fluorinated back to UF
493:Electromagnetic separation is
1:
1082:The Making of the Atomic Bomb
849:kilogram separative work unit
397:Oak Ridge National Laboratory
940:1 MSWU = 1 kt SW = 1 kt UTA
937:1 kSWU = 1.0 t SW = 1 t UTA
326:it became an atom bomb state
104:Those based directly on the
1707:
1602:"IGISOL — Fysiikan laitos"
1386:(1 Third Confere): 71–80.
981:Beam production capability
574:used in AVLIS include the
18:Electromagnetic separation
1666:World Nuclear Association
1574:"ISOLDE official webpage"
1303:Reviews of Modern Physics
1245:10.1080/14786440508635912
376:Clinton Engineering Works
147:from the common impurity
1344:p. c., Haarhoff (1976).
1323:10.1103/revmodphys.56.41
1157:"Plasma mass separation"
686:Stern–Gerlach experiment
601:) or in the UV, frees a
153:gun-type fission weapons
1475:. Amsterdam: Elsevier.
1078:Richard Rhodes (1986).
956:Arguably the principal
728:kinetic isotopic effect
713:Girdler sulfide process
662:electric dipole moments
1280:10.1103/physrev.50.491
1233:Philosophical Magazine
847:The unit is strictly:
804:energy of vaporization
678:
490:
424:
346:
1057:The Register: Channel
825:The C enrichment by (
679:
607:uranium pentafluoride
568:nuclear proliferation
485:
432:Zippe-type centrifuge
422:
374:separation plants at
344:
226:thermonuclear weapons
139:from the more common
838:Separative work unit
833:Separative work unit
677:{\displaystyle \pi }
668:
591:uranium hexafluoride
401:Oak Ridge, Tennessee
384:uranium hexafluoride
238:thermal conductivity
176:Commercial materials
63:nuclear power plants
1627:"LISOL @ KU Leuven"
1315:1984RvMP...56...41W
1272:1936PhRv...50..491B
1175:2018PhPl...25i0901Z
1136:Centrus Energy Corp
441:medical centrifuges
281:light-water reactor
159:Enrichment cascades
1686:Isotope separation
1660:2010-12-02 at the
1655:Uranium Enrichment
1650:Uranium Production
1162:Physics of Plasmas
1034:Arms Control Today
970:surface ionization
674:
654:Trojan wave packet
578:and more recently
519:first atomic bombs
515:Ernest O. Lawrence
491:
425:
347:
291:. Options include
120:nuclear resonances
86:chemical processes
31:Isotope separation
1691:German inventions
1482:978-0-444-52981-7
1183:10.1063/1.5042845
1119:http://www.world-
1097:978-0-684-81378-3
855:of feed of assay
796:theoretical plate
781:
780:
546:Coulomb potential
533:In this method a
495:mass spectrometry
380:Manhattan Project
372:gaseous diffusion
299:type reactors or
285:neutron moderator
170:separation factor
16:(Redirected from
1698:
1631:
1630:
1623:
1617:
1616:
1614:
1613:
1598:
1592:
1591:
1584:
1578:
1577:
1570:
1564:
1563:
1551:
1545:
1544:
1542:
1541:
1532:. Archived from
1526:
1520:
1519:
1517:
1516:
1501:
1495:
1494:
1468:
1462:
1459:
1453:
1447:
1441:
1434:
1428:
1418:
1412:
1411:
1371:
1365:
1364:
1356:
1350:
1349:
1341:
1335:
1334:
1298:
1292:
1291:
1255:
1249:
1248:
1239:(221): 523–534.
1217:
1211:
1210:
1152:
1146:
1145:
1143:
1142:
1128:
1122:
1115:
1109:
1108:
1106:
1104:
1085:
1075:
1069:
1068:
1066:
1064:
1048:
1042:
1041:
1029:
777:k(H)/k(T) = 305
765:k(D)/k(T) = 8.1
743:
742:
692:Chemical methods
683:
681:
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504:isotopic tracers
283:is the use of a
272:which decays to
190:enriched uranium
59:depleted uranium
55:enriched uranium
39:chemical element
21:
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1606:the original
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1538:. Retrieved
1534:the original
1524:
1513:. Retrieved
1509:the original
1499:
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1457:
1450:F. J. Duarte
1445:
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1420:Werner Fuß:
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1235:. Series 6.
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1225:Aston, F. W.
1215:
1166:
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1139:. Retrieved
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1101:. Retrieved
1081:
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1061:. Retrieved
1056:
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1015:, in Japan.
1001:
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859:into a mass
856:
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789:
786:Distillation
774:) = 9.54 Ms
762:) = 9.54 Ms
750:) = 9.54 Ms
725:
702:
695:
647:
627:
619:
584:
580:diode lasers
557:
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492:
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464:South Africa
460:Vortex tubes
458:
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389:
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356:Knudsen flow
348:
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255:
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248:Alternatives
242:
231:
196:fuel and in
179:
162:
125:
99:
83:
78:
30:
29:
1103:January 17,
1063:January 17,
915:) ln ((1 -
709:heavy water
428:Centrifugal
415:Centrifugal
332:Methodology
303:as used in
295:as used in
293:heavy water
208:heavy water
192:for use as
141:uranium-238
137:uranium-235
71:uranium-233
1680:Categories
1612:2014-02-18
1562:(1): 1–14.
1540:2007-09-01
1515:2014-02-18
1141:2023-04-30
1019:References
1011:(RIBF) at
991:Jyväskylä
988:Refractory
911:) = (1 - 2
867:and assay
472:jet nozzle
96:Techniques
1664:from the
1491:162588020
1400:0077-8923
1331:0034-6861
1288:0031-899X
1207:226888946
1191:1070-664X
1132:"Paducah"
993:cyclotron
895:), where
827:cryogenic
705:evaporate
672:π
664:are then
650:deuterium
576:dye laser
552:hyperfine
523:calutrons
466:in their
362:versus UF
351:diffusion
337:Diffusion
222:Lithium-6
129:deuterium
90:deuterium
75:plutonium
47:chemistry
1658:Archived
1408:97058155
1227:(1919).
603:fluorine
488:calutron
301:graphite
204:Hydrogen
133:hydrogen
69:(unless
43:nuclides
35:isotopes
1311:Bibcode
1268:Bibcode
1199:1472074
1171:Bibcode
997:Finland
792:columns
736:formate
732:tritium
717:cascade
658:reduced
289:protium
262:Fissile
234:silicon
214:Tritium
186:Uranium
166:cascade
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1094:
810:O to D
721:Rjukan
436:plasma
403:, and
305:magnox
274:Am-241
270:Pu-241
266:Pu-240
1404:S2CID
1203:S2CID
1013:RIKEN
818:to CH
770:k(TCO
758:k(DCO
746:k(HCO
595:U-235
535:laser
529:Laser
322:India
297:CANDU
79:grade
53:into
37:of a
1487:OCLC
1477:ISBN
1396:ISSN
1327:ISSN
1284:ISSN
1195:OSTI
1187:ISSN
1105:2014
1092:ISBN
1065:2014
887:) -
879:) +
842:i.e.
309:RBMK
57:and
1388:doi
1384:267
1319:doi
1276:doi
1241:doi
1179:doi
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443:).
407:in
399:in
307:or
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893:xf
889:FV
885:xp
881:PV
877:xw
873:WV
869:xw
857:xf
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