Pu-241

Pu-241 is isotope of Plutonium.

mass: 241.057 amu

halflife : 14.89 ± 0.11 yr.

Energy of the spontaneous decay of Pu-241: 21 KeV ;
then, the resulting Am-241 gives 4.959 MeV.

Production

Isotopes of Plutonium appear in the commercial nuclear plants as by-products.

\(\mathrm{^{238}_{\ 92}U\ \xrightarrow {(n,\gamma)} \ ^{239}_{\ 92}U\ \xrightarrow [23.5 \ min]{\beta^-} \ ^{239}_{\ 93}Np\ \xrightarrow [2.3565 \ d]{\beta^-} \ ^{239}_{\ 94}Pu}\)

The capture of two neutrons by ²³⁹Pu (a so-called (n,γ) reaction), followed by a β-decay, results in ²⁴¹Am:

\( \mathrm{^{239}_{\ 94}Pu\ \xrightarrow {2~(n,\gamma)} \ ^{241}_{\ 94}Pu\ \xrightarrow [15 \ yr]{\beta^-} \ ^{241}_{\ 95}Am} \)

Most or nuclear reactors have significant concentration of U-238 in the active rods; so, production of plutonium happens automatically, whether it is wanted of not.

At accidents with nuclear plants, isotopes of Plutonium appear as one of main contaminants. Then, it decays to Americium, that becomes the main contaminant at the scale larger than a century.

Using

\( \rm ^{241}_{~94}Pu \xrightarrow[15~y]{\beta^-,~ 21\,KeV} {} ^{241}_{~95}Am \xrightarrow[432.7\,y]{\alpha,\, 4.959\,MeV} {}^{237}_{~96}Np \xrightarrow[2.4 \times 10^6\,y]{\alpha,~4.958 \,MeV} \mathrm{^{233}_{91}Pa} ~.\,.\,. \)

The resulting Americium appears in significant amount in the nuclear waste and is reported to be important (and even dominant) contaminant since some tens of years since the nuclear disasters.

As soon, as the collection and extraction of the Americium, Plutonium and other isotopes from the nuclear waste is arranged, the question arise about the applications. One such application is described in utopia Tartaria mentioned below.

Fiction

Decay heat by mixture of Pu-241 and Am-241 versus time

The cascade decay above is described in Utopia Tartaria.

One impostors, pretending to be a specialist, declares, that from the nuclear waste and contaminated soil, he can make warming devices based on the decay heat. Such a heater is declared to produce a kilowatt power during a century, with relative variation of this power within 10%. With this specification, company Norga warm gets the huge federal grant, promising to manufacture an example of such a heater within two years. The laboratory is constructed to select, separate, rectify the nuclear waste and contaminated soul. It grows up to a big factory, but the goal declared seem to be unreachable. In the waste they work with, no one isotope allows to satisfy the criteria declared. The project is about to be qualified as a fraud and the money laundering, with catastrophic sequences for the Mozdok Tsuker, owner of the Norga warm.

One visitor-scientist, Ruvim Pechor, happens at the Norga warm. Ruvim suggests the compound heating substance, containing, roughly, 8 kg of Am-241 and 2 kg of Pu-241. During some tens of years, the depletion of Am-241 is partially compensated by conversion of Pu-241 into Am-241. The heat due to the beta decay of Pu-241 is negligible, but the alfa decay of Am-241, due to the partial recovery of its amount, provides the stability declared. Ruvim Pechor illustrates his project with the explicit plot, simulation of the heat generation versus time. At the diagram, the starting point of the device corresponds to abscissa of order of "40 years".

No other way to save the project is suggested; so, the head of project orders his staff to follow recommendation by Ruvim Pechir; Ruvim gets title "top scientist" of the Norga warm company. The top chemist, attractive woman (Pesia Zivertov) makes the special rectification machines and extracts the required amount of Am-241 and Pu-241. Then, the top engineer (Femistolkus Zalipaev) packs this to Zirconium tubes; the resulting apparatus is called Century Heater. This name is shortened to "C-Heater", then to "Cheater". Them the short name is "translated" into Russian as Сплeтник, and transliterated back into English as Spletnik; this name becomes the usual term to denote the device.

Formula of the invention

Device on the spontaneous decay of unstable isotopes, characterized in that,
that, in order to reduce variation of the generated power, the mixture of isotopes is used in such a way, that the depletion of the main working isotope is partially compensated by the decay of its parent isotope.
The example of such a mixture, Pu-241 and Am-241, is mentioned in the previous section.

If someone finds a publication with such (or equivalent) description, them, please, communicate the Editor of TORI.

Waring

The most of data are from Wikipedia.

Some additional misprints from Wikipedia may appear here in addition to those made by the Editor of TORI.

References

https://en.wikipedia.org/wiki/Americium-241

https://en.wikipedia.org/wiki/Plutonium-241

https://en.wikipedia.org/wiki/MOX_fuel All plutonium isotopes are either fissile or fertile, although plutonium-242 needs to absorb 3 neutrons before becoming fissile curium-245; in thermal reactors isotopic degradation limits the plutonium recycle potential. About 1% of spent nuclear fuel from current LWRs is plutonium, with approximate isotopic composition Pu-239 52%, Pu-240 24%, Pu-241 15%, Pu-242 6%, Pu-238 2%.
https://ru.wikipedia.org/wiki/MOX-топливо Плутоний составляет порядка 1% от облучённого ядерного топлива. Приблизительное изотопное соотношение: Pu-239 52%, Pu-240 24%, Pu-241 15%, Pu-242 6%, Pu-238 2%.

2008.08.oo. https://web.archive.org/web/20110525233310/http://www.nda.gov.uk/documents/ upload/Plutonium-Options-for-Comment-August-2008.pdf NDA Plutonium Options. SMS Plutonium Topic Strategy, August 2008 - October 2008. Table 1: Examples of the types of variation in plutonium composition produced from different sources

2016.05.23. http://greenbelarus.info/articles/23-05-2016/eho-chernobylya-kak-smertelno-opasnyy-produkt-raspada-plutoniya-americiy Андрей Скурко. Эхо Чернобыля: как смертельно опасный америций угрожает здоровью и жизни беларусов? ЗЯЛЁНЫ ПАРТАЛ, 2016.05.23.

Keywords

Am-241, Relaxation heat, Tartaria03