Wyniki wyszukiwania - BazTech

1

Radionuclide neutron source trajectories in the closed nuclear fuel cycle

Stanisz Przemysław, Cetnar Jerzy, Oettingen Mikołaj

Nukleonika

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2019

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Vol. 64, No. 1

3--9

EN

The highest efficiency in the usage of nuclear energy resources can be implemented in fast breeder reactors of generation IV. It is achieved thanks to the ability of consuming minor actinides (MAs) in energy production. One of the options to use this benefit is full recycling of MAs to close the nuclear fuel cycle. Monte Carlo burn up (MCB), an integrated burn-up calculation code, deals with the complexity of the burn-up process which is applied to the European Lead-cooled Fast Reactor (ELFR). MCB uses continuous energy representation of cross section and spatial effects of full core reactor model; however, it automatically calculates nuclide production in all possible reactions or decay channels. Multi-recycling of MAs can cause an intensified build-up of curium, berkelium and californium. Some of their isotopes are strong neutron emitters from spontaneous fission, which hinders fuel recycling. The implementation of a novel methodology for trajectory period folding allows us to trace the life cycle of crucial MAs from the beginning of the reactor life towards the state of adiabatic equilibrium. The result of the analysis performed is presented, showing the sources of strong contribution to the neutron production rate. The parametric sensitivity analysis method for selected nuclide reactions is applied, revealing sensitivity of transmutation chains for the production of neutron emitter isotopes.

2

Zamieszkiwanie w betonie

Ciepłucha W.

Pretekst

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2018

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Nr 8

54--60

PL

Piękne odnosi się do tego co już uformowane, ukształtowane, a nie do budynku architektonicznego. Sama forma nie jest jeszcze budynkiem architektonicznym, ale dopiero tym co estetyczne. Zakładając, że forma jest już stworzona, twórca stoi na progu. Z jednej strony jest to, co uformowane, z drugiej strony budynek architektoniczny. Czynność, która polega na nadaniu formie znaczenia, nazwiemy transmutacją. Wiele transmutacji składa się na zamieszkiwanie. Im wrażliwiej transmutujemy materie z której jest zbudowana forma, tym bardziej zamieszkujemy.

EN

Beauty relates to what has been formed, shaped, and not to an architectural building. The form itself is not yet an architectural building, but only that, which is aesthetic. Assuming that the form has been created, the creator is at a verge, with that, which is formed on one hand, and the architectural building on the other. The act of giving meaning to form will be called transmutation. Many transmutations make up dwelling. The more sensitive we are in transmuting the matter of which the form is built, the more we dwell.

3

Przeniesienia

Trillo de Leyva J. L., Dorado J. A.

Pretekst

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2018

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Nr 8

42--46

PL

Beton odzwierciedla naturalny proces kształtowania się kamienia, streszczając tysiące lat w kilku dniach. Przeniesienia takich obrazów z powierzchni jak skamieniałości są natychmiastowe; kamień i beton stają się środkiem, który przenosi obrazy miejsca i minionego czasu w przyszłość. Rzeźbiarz Eduardo Chillida miał swój udział w przemianach i przeniesieniach betonu.

EN

The concrete repeats the natural process of stone formation, thousands of years summarized in days. Transfers of surface images, such as fossils, are instantaneous; stone and concrete become a means that translates to the future the images of a place and a past time. The sculptor Eduardo Chillida has contributed to the transmutation and transfer of concrete.

4

Transmutation: reducing the storage time of spent fuel

Mazgaj P., Darnowski P.

Journal of Power Technologies

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2014

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Vol. 94, nr 5

27--34

EN

Transmutation can reduce the storage time of spent fuel. Efficient transmutation requires a high flux of neutrons and can therefore be done only in nuclear reactors. The article shows the concepts of different solutions of transmutation in nuclear reactors. Knowledge of transmutation is supplemented by information on spent fuel and its radiotoxicity.

5

Design of a sub-critical reactor for transmutation of higher actinides

Mazgaj P., Jimenez D., Lopez D.

Journal of Power Technologies

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2014

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Vol. 94, nr 5

35--40

EN

To reduce the storage time of spent fuel its radiotoxicity must be reduced through the transmutation of minor actinides. Generation IV reactors or sub-critical Accelerator Driven Systems (ADS) are options that appear technically feasible in view of the transmutation goal. The purpose of this work is to design a lead-cooled 400 MWth sub-critical reactor which uses inert matrix nitride fuel. Many design issues are dealt with, such as the lifetime of the cladding material, the minimum reactivity swing fuel composition, the burning rates of MA and the safety coefficients. The results obtained show that ADS performs well in transmuting minor actinides and has good safety levels in respect of reactivity perturbations.

6

Safety issues as a start point for further investigations of fusion hybrids

Wójcik G., Taczanowski S.

Nukleonika

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2012

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Vol. 57, No. 4

447-450

EN

Nuclear power plants supply nearly one sixth of the world electric energy production. Though nuclear power is a very efficient source of energy, it produces dangerous radioactive waste composed of nuclides characterized, among others, by a long decay time and containing also significant quantities of fissible and even fissile materials. Therefore, spent nuclear fuel must be carefully stored for at least hundreds of years, all this time needing permanent supervision. Simultaneously this cumbersome waste contains also important amounts of energy that should not be simply buried forever. Thus, in spite of the fact that ultimate disposal of spent nuclear fuel in adequate geological formations is recognized as safe for the energy hungry world that tries at the same time to avoid CO2 emissions, this is a hardly acceptable solution. Fortunately, there is an effective approach, namely – spent fuel recycling, particularly with the help of nuclear fusion. Simultaneously, one has to admit that this concept has not attained yet technological maturity, thus lengthy and costly investigations still are necessary before nuclear fusion achieves development level adequate to industrial application. Since every nuclear device must be generally safe, therefore this article raises a safety issue of fusion-fission hybrid design. In order to ensure the required reliability of evaluations the development of heterogeneous model of the device was assumed as the starting point for further respective research. The performed calculations have indicated that maintenance of subcriticality even in the case of system collapse is achievable.