988:. 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.
472:
331:
409:
818:) 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.
555:). 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
514:. 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.
265:, 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.
459:. 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
383:
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
241:
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
152:
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
965:
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
941:
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
435:
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
961:
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
490:
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
991:
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
979:
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
633:
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
444:
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
342:
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
949:
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
427:
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
375:
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.
795:, 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
440:
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.
445:
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.
300:
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
942:
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.
609:
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
115:
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,
787:
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.
974:
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.
614:). 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.
992:
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
355:
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.
232:
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.
169:
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:
649:
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
840:, 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
436:
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
950:
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.
526:
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
400:. 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.
933:
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%.
317:
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.
671:
953:
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
803:
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
1659:
50:
is the largest application. In the following text, mainly uranium enrichment is considered. This process is crucial in the manufacture of uranium fuel for
606:
before being introduced into the next MLIS stage. But with light elements, the isotope selectivity is usually good enough that cascading is not required.
1590:
221:
Some isotopically purified elements are used in smaller quantities for specialist applications, especially in the semiconductor industry, where purified
158:
625:
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
463:
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.
419:
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
77:, isotopes of the same element have nearly identical chemical properties which makes this type of separation impractical, except for separation of
205:
is both a nuisance in the coolant / moderator of water moderated reactors and a valuable product; it is thus sometimes separated from the coolant.
622:
685:
Although isotopes of a single element are normally described as having the same chemical properties, this is not strictly true. In particular,
1632:
993:
966:
Ionization Laser Ion Source (RILIS). Currently over 60% of all experiments opt to use the RILIS to increase the purity of radioactive beams.
547:
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
1209:
618:
783:. The separation factor is the ratio of vapor pressures of two isotopic molecules. In equilibrium such a separation results at each
486:
on a large scale, so it is sometimes referred to as mass spectrometry. It uses the fact that charged particles are deflected in a
347:). 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
305:, which ultimately led to the replacement of this fuel with low enriched uranium, negating the advantage of foregoing enrichment.
1493:
268:
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
66:
produced in a nuclear reactor, which must be operated in such a way as to produce plutonium already of suitable isotopic mix or
1469:
1084:
552:
1518:
598:
which then precipitates out of the gas. Cascading the MLIS stages is more difficult than with other methods because the UF
1638:
829:(SWU) is a complex unit which is a function of the amount of uranium processed and the degree to which it is enriched,
575:
499:
393:
1646:
1120:
611:
587:
456:
1290:
Whitley, Stanley (1984-01-01). "Review of the gas centrifuge until 1962. Part I: Principles of separation physics".
779:
Isotopes of hydrogen, carbon, oxygen, and nitrogen can be enriched by distilling suitable light compounds over long
997:
380:
306:
108:
962:
those with a heavier mass. This differing radius of curvature allows for isobaric purification to take place.
705:
154:
1594:
815:
704:
for details. Lighter isotopes also disassociate more rapidly under an electric field. This process in a large
692:
Techniques using this are most effective for light atoms such as hydrogen. Lighter isotopes tend to react or
385:
673:-shifted in phase and the beam of such atoms splits in the gradient of the electric field in the analogy to
1460:
B.M. Andreev; E.P.Magomedbekov; A.A. Raitman; M.B.Pozenkevich; Yu.A. Sakharovsky; A.V. Khoroshilov (2007).
674:
161:, which is a number greater than 1. The second is the number of required stages to get the desired purity.
1674:
1364:
1615:
471:
1679:
1660:
Annotated bibliography on electromagnetic separation of uranium isotopes form the Alsos
Digital Library
289:
253:
Pu-239 is produced following neutron capture by uranium-238, but further neutron capture will produce
1654:
534:
364:
38:
where atoms of "marker" nuclide are used to figure out reaction mechanisms). By tonnage, separating
860:
is expressed in terms of the number of separative work units needed, given by the expression SWU =
314:
157:. There are two important factors that characterize the performance of a cascade. The first is the
1365:"The Laser Isotope Separation Program at Lawrence Livermore Laboratory.: Laser Isotope Separation"
1041:
641:
separation using Trojan wavepackets in circularly polarized electromagnetic field. The process of
153:
to the previous stage for further processing. This creates a sequential enriching system called a
701:
313:
which has limited domestic uranium resources and been under a partial nuclear embargo ever since
141:
359:
The first large-scale separation of uranium isotopes was achieved by the United States in large
792:
716:
650:
310:
1426:
1350:"Uranium enrichment by jet nozzle separation process in the German-Brazil cooperation program"
1349:
1076:
229:, and carbon with greater isotopic purity to make diamonds with greater thermal conductivity.
1334:
1213:
595:
559:, because it may be cheaper and more easily hidden than other methods of isotope separation.
556:
429:
420:
1543:
Miller, Alistair I. (2001). "Heavy Water: A Manufacturers' Guide for the
Hydrogen Century".
833:
the extent of increase in the concentration of the U-235 isotope relative to the remainder.
330:
1299:
1256:
1159:
826:
780:
579:
389:
372:
226:
214:
656:
8:
540:
344:
269:
51:
1303:
1260:
1247:
Beams, J. W.; Haynes, F. B. (1936-09-01). "The
Separation of Isotopes by Centrifuging".
1163:
1459:
1392:
1380:
1191:
1150:
958:
957:
allowing for collisions with the walls to liberate a single electron from a free atom (
642:
503:
242:
of other elements are not so great a problem as they can be removed by chemical means.
217:. Tritium is commonly produced from lithium-6 which is often enriched for this purpose.
1497:
1475:
1465:
1384:
1315:
1272:
1195:
1183:
1175:
1080:
1069:
784:
719:
ever measured at room temperature, 305, may eventually be used for the separation of
507:
483:
416:
368:
360:
277:
273:
74:
1396:
1441:
and L.W. Hillman (Eds.), Dye Laser Principles (Academic, New York, 1990) Chapter 9.
1376:
1307:
1264:
1229:
1167:
424:
178:
47:
43:
27:
249:
for use in weapons. It is not practical to separate Pu-239 from Pu-240 or Pu-241.
1650:
492:
302:
186:
182:
39:
1522:
1144:
Zweben, Stewart J.; Gueroult, Renaud; Fisch, Nathaniel J. (12 September 2018).
645:
formation by the adiabatic-rapid passage depends in ultra-sensitive way on the
548:
487:
55:
1450:
F. J. Duarte (Ed.), Tunable Laser Applications, 2nd Ed. (CRC, 2008) Chapter 11
1233:
1668:
1479:
1388:
1319:
1311:
1276:
1179:
954:
696:
more quickly than heavy isotopes, allowing them to be separated. This is how
686:
582:
gas (if enrichment of uranium is desired), exciting molecules that contain a
560:
397:
246:
137:
133:
101:
94:
1414:
1643:
1438:
1268:
646:
452:
107:
Those based on properties not directly connected to atomic weight, such as
697:
693:
583:
568:
506:
developed electromagnetic separation for much of the uranium used in the
448:
408:
281:
257:
which is less fissile and worse, is a fairly strong neutron emitter, and
196:
129:
125:
59:
1110:
nuclear.org/info/Country-Profiles/Countries-T-Z/USA--Nuclear-Fuel-Cycle/
915:
Separative work is expressed in SWUs, kg SW, or kg UTA (from the German
1633:
Utilization of kinetic isotope effects for the concentration of tritium
1519:"Laboratory alliance to put "Made in America" stamp on stable isotopes"
976:
1187:
1171:
1145:
791:
The lower vapor pressure of the heavier molecule is due to its higher
981:
638:
564:
339:
210:
117:
78:
63:
35:
34:
produced is varied. The largest variety is used in research (e.g. in
1217:
1021:
Garwin, Richard L. (Nov 1997). "The Technology of Nuclear Weapons".
591:
511:
476:
192:
121:
31:
985:
724:
720:
250:
222:
202:
174:
23:
709:
543:
splitting of electronic transitions, if the nucleus has a spin,
293:
262:
258:
254:
245:
This is particularly relevant in the preparation of high-grade
412:
A cascade of gas centrifuges at a US uranium enrichment plant.
334:
Gaseous diffusion uses microporous membranes to enrich uranium
1496:. Los Alamos National Laboratory. Winter 2003. Archived from
1001:
523:
285:
1576:
637:
Quite recently yet another scheme has been proposed for the
1427:
https://inis.iaea.org/search/search.aspx?orig_q=rn:27014297
297:
1106:
World Nuclear Association, US Nuclear Fuel Cycle, (2015),
578:(MLIS). In this method, an infrared laser is directed at
140:, while desirable in that it would allow the creation of
124:
and it is generally easier to purify it than to separate
530:
the nuclear mass (noticeable mainly with light elements)
89:
There are three types of isotope separation techniques:
1562:
144:
from plutonium, is generally agreed to be impractical.
54:
and is also required for the creation of uranium-based
1425:
Schneider, K. R., LIS: the view from Urenco (1995). (
659:
475:
Schematic diagram of uranium isotope separation in a
16:
Concentrating specific isotopes of a chemical element
1413:. (PDF) Max-Planck-Institut für Quantenoptik, 2015,
1107:
1143:
276:with a lower neutron absorption cross section than
1068:
936:
665:
338:Often done with gases, but also with liquids, the
1042:"AMD tests 'super silicon' to beat heat problems"
533:the nuclear volume (causing a deviation from the
100:Those based on the small differences in chemical
1666:
1411:Laser isotope separation and proliferation risks
723:(T). The effects for the oxidation of tritiated
708:was used at the heavy water production plant at
574:A second method of laser separation is known as
73:While chemical elements can be purified through
1255:(5). American Physical Society (APS): 491–492.
996:(NSCL) at Michigan State University and at the
1335:"The Helikon technique for isotope enrichment"
1208:
1066:
309:such as the CANDU are still in active use and
132:. On the other extreme, separation of fissile
1363:Stern, R. C.; Snavely, B. B. (January 1976).
1298:(1). American Physical Society (APS): 41–66.
994:National Superconducting Cyclotron Laboratory
969:
586:atom. A second laser, either also in the IR (
551:. This method is often abbreviated as AVLIS (
379:The last diffusion plant closed in 2013. The
1362:
634:separated from the excited lighter isotope.
498:At Oak Ridge National Laboratory and at the
199:for use as a moderator in nuclear reactors.
1462:Separation of isotopes of biogenic elements
1246:
689:are very slightly affected by atomic mass.
30:by removing other isotopes. The use of the
1369:Annals of the New York Academy of Sciences
619:Separation of isotopes by laser excitation
1415:https://www.mpq.mpg.de/5178012/MPQ346.pdf
1060:
495:) but is impractical for industrial use.
225:is used to improve crystal structure and
22:is the process of concentrating specific
1218:"The possibility of separating isotopes"
510:. Devices using his principle are named
470:
407:
367:, which were established as part of the
329:
195:isotopes have been separated to prepare
177:isotopes have been separated to prepare
1289:
821:
384:that processed the enriched uranium at
164:
120:has twice the mass of ordinary (light)
1667:
1542:
1039:
1020:
892:) is the "value function," defined as
852:of product assay xp and waste of mass
147:
62:is used). Plutonium-based weapons use
1332:
923:1 SWU = 1 kg SW = 1 kg UTA
553:atomic vapor laser isotope separation
104:produced by different atomic weights.
1593:(in Finnish). Jyu.fi. Archived from
1040:Thomas, Andrew (November 30, 2000).
811:near 111.7 K (boiling point).
680:
13:
1635:, GM Brown, TJ Meyer et al., 2001.
1494:"Spotlight Los Alamos in the News"
1453:
1381:10.1111/j.1749-6632.1976.tb41598.x
576:molecular laser isotope separation
537:, noticeable for heavier elements)
500:University of California, Berkeley
466:
394:Portsmouth Gaseous Diffusion Plant
14:
1691:
1626:
1545:Canadian Nuclear Society Bulletin
1347:
629:in a carrier gas, in which the UF
588:infrared multiphoton dissociation
457:Helikon vortex separation process
213:has been concentrated for use in
1075:. Simon & Schuster. p.
998:Radioactive Isotope Beam Factory
947:Isotope Separator On Line (ISOL)
727:anions to HTO were measured as:
621:' (SILEX) process, developed by
307:Pressurized heavy-water reactors
1608:
1583:
1569:
1555:
1536:
1511:
1486:
1444:
1432:
1419:
1403:
1356:
1341:
1326:
937:Isotope separators for research
774:
612:IR Multiple Photon Dissociation
381:Paducah Gaseous Diffusion Plant
236:
1283:
1240:
1202:
1137:
1113:
1100:
1033:
1029:(8): 6–7 – via Proquest.
1014:
715:One candidate for the largest
700:is produced commercially, see
602:must be fluorinated back to UF
482:Electromagnetic separation is
403:
320:
1:
1071:The Making of the Atomic Bomb
1007:
838:kilogram separative work unit
386:Oak Ridge National Laboratory
84:
929:1 MSWU = 1 kt SW = 1 kt UTA
926:1 kSWU = 1.0 t SW = 1 t UTA
325:
315:it became an atom bomb state
93:Those based directly on the
7:
10:
1696:
1591:"IGISOL — Fysiikan laitos"
1375:(1 Third Confere): 71–80.
970:Beam production capability
563:used in AVLIS include the
1655:World Nuclear Association
1563:"ISOLDE official webpage"
1292:Reviews of Modern Physics
1234:10.1080/14786440508635912
365:Clinton Engineering Works
136:from the common impurity
1333:p. c., Haarhoff (1976).
1312:10.1103/revmodphys.56.41
1146:"Plasma mass separation"
675:Stern–Gerlach experiment
590:) or in the UV, frees a
517:
142:gun-type fission weapons
1464:. Amsterdam: Elsevier.
1067:Richard Rhodes (1986).
945:Arguably the principal
717:kinetic isotopic effect
702:Girdler sulfide process
651:electric dipole moments
1269:10.1103/physrev.50.491
1222:Philosophical Magazine
836:The unit is strictly:
793:energy of vaporization
667:
479:
413:
335:
1046:The Register: Channel
814:The C enrichment by (
668:
596:uranium pentafluoride
557:nuclear proliferation
474:
421:Zippe-type centrifuge
411:
363:separation plants at
333:
215:thermonuclear weapons
128:from the more common
827:Separative work unit
822:Separative work unit
666:{\displaystyle \pi }
657:
580:uranium hexafluoride
390:Oak Ridge, Tennessee
373:uranium hexafluoride
227:thermal conductivity
165:Commercial materials
52:nuclear power plants
1616:"LISOL @ KU Leuven"
1304:1984RvMP...56...41W
1261:1936PhRv...50..491B
1164:2018PhPl...25i0901Z
1125:Centrus Energy Corp
430:medical centrifuges
270:light-water reactor
148:Enrichment cascades
1675:Isotope separation
1649:2010-12-02 at the
1644:Uranium Enrichment
1639:Uranium Production
1151:Physics of Plasmas
1023:Arms Control Today
959:surface ionization
663:
643:Trojan wave packet
567:and more recently
508:first atomic bombs
504:Ernest O. Lawrence
480:
414:
336:
280:. Options include
109:nuclear resonances
75:chemical processes
20:Isotope separation
1680:German inventions
1471:978-0-444-52981-7
1172:10.1063/1.5042845
1108:http://www.world-
1086:978-0-684-81378-3
844:of feed of assay
785:theoretical plate
770:
769:
535:Coulomb potential
522:In this method a
484:mass spectrometry
369:Manhattan Project
361:gaseous diffusion
288:type reactors or
274:neutron moderator
159:separation factor
1687:
1620:
1619:
1612:
1606:
1605:
1603:
1602:
1587:
1581:
1580:
1573:
1567:
1566:
1559:
1553:
1552:
1540:
1534:
1533:
1531:
1530:
1521:. Archived from
1515:
1509:
1508:
1506:
1505:
1490:
1484:
1483:
1457:
1451:
1448:
1442:
1436:
1430:
1423:
1417:
1407:
1401:
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1018:
766:k(H)/k(T) = 305
754:k(D)/k(T) = 8.1
732:
731:
681:Chemical methods
672:
670:
669:
664:
493:isotopic tracers
272:is the use of a
261:which decays to
179:enriched uranium
48:depleted uranium
44:enriched uranium
28:chemical element
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467:Electromagnetic
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303:natural uranium
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1599:. Retrieved
1595:the original
1585:
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1538:
1527:. Retrieved
1523:the original
1513:
1502:. Retrieved
1498:the original
1488:
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1455:
1446:
1439:F. J. Duarte
1434:
1421:
1410:
1409:Werner Fuß:
1405:
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1224:. Series 6.
1221:
1214:Aston, F. W.
1204:
1155:
1149:
1139:
1128:. Retrieved
1124:
1115:
1102:
1090:. Retrieved
1070:
1062:
1050:. Retrieved
1045:
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1026:
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1016:
1004:, in Japan.
990:
973:
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849:
848:into a mass
845:
841:
837:
835:
830:
825:
813:
790:
778:
775:Distillation
763:) = 9.54 Ms
751:) = 9.54 Ms
739:) = 9.54 Ms
714:
691:
684:
636:
616:
608:
573:
569:diode lasers
546:
521:
497:
481:
460:
453:South Africa
449:Vortex tubes
447:
443:
434:
415:
378:
358:
345:Knudsen flow
337:
267:
244:
240:
237:Alternatives
231:
220:
185:fuel and in
168:
151:
114:
88:
72:
67:
19:
18:
1092:January 17,
1052:January 17,
904:) ln ((1 -
698:heavy water
417:Centrifugal
404:Centrifugal
321:Methodology
292:as used in
284:as used in
282:heavy water
197:heavy water
181:for use as
130:uranium-238
126:uranium-235
60:uranium-233
1669:Categories
1601:2014-02-18
1551:(1): 1–14.
1529:2007-09-01
1504:2014-02-18
1130:2023-04-30
1008:References
1000:(RIBF) at
980:Jyväskylä
977:Refractory
900:) = (1 - 2
856:and assay
461:jet nozzle
85:Techniques
1653:from the
1480:162588020
1389:0077-8923
1320:0034-6861
1277:0031-899X
1196:226888946
1180:1070-664X
1121:"Paducah"
982:cyclotron
884:), where
816:cryogenic
694:evaporate
661:π
653:are then
639:deuterium
565:dye laser
541:hyperfine
512:calutrons
455:in their
351:versus UF
340:diffusion
326:Diffusion
211:Lithium-6
118:deuterium
79:deuterium
64:plutonium
36:chemistry
1647:Archived
1397:97058155
1216:(1919).
592:fluorine
477:calutron
290:graphite
193:Hydrogen
122:hydrogen
58:(unless
32:nuclides
24:isotopes
1300:Bibcode
1257:Bibcode
1188:1472074
1160:Bibcode
986:Finland
781:columns
725:formate
721:tritium
706:cascade
647:reduced
278:protium
251:Fissile
223:silicon
203:Tritium
175:Uranium
155:cascade
1478:
1468:
1395:
1387:
1318:
1275:
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1186:
1178:
1083:
799:O to D
710:Rjukan
425:plasma
392:, and
294:magnox
263:Am-241
259:Pu-241
255:Pu-240
1393:S2CID
1192:S2CID
1002:RIKEN
807:to CH
759:k(TCO
747:k(DCO
735:k(HCO
584:U-235
524:laser
518:Laser
311:India
286:CANDU
68:grade
42:into
26:of a
1476:OCLC
1466:ISBN
1385:ISSN
1316:ISSN
1273:ISSN
1184:OSTI
1176:ISSN
1094:2014
1081:ISBN
1054:2014
876:) -
868:) +
831:i.e.
298:RBMK
46:and
1377:doi
1373:267
1308:doi
1265:doi
1230:doi
1168:doi
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432:).
396:in
388:in
296:or
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882:xf
878:FV
874:xp
870:PV
866:xw
862:WV
858:xw
846:xf
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