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1

Radiografia w ochronie dziedzictwa kulturowego

Głuszewski Wojciech

Postępy Techniki Jądrowej

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2022

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z. 4

31--35

PL

Metody radiograficzne pozwalają za pomocą promieniowań X oraz gamma (γ) wykrywać wewnętrzne niezgodności w całej objętości materiału. W zasadzie nie ma ograniczeń co do rodzaju badanych obiektów. Warunkiem jest jedynie dostęp do dwóch stron napromieniowywanego przedmiotu lub konstrukcji. Alternatywą dla analogowych, błonowych technik radiograficznych jest radiografia cyfrowa. O jakości obrazu i dawce pochłoniętej decyduje technologia przetwarzania promieniowania hamowania na sygnał cyfrowy. Postęp w radiografii stymulowany jest głównie przez zastosowania medyczne i przemysłowe. Z nowych rozwiązań mogą korzystać również konserwatorzy dzieł sztuki. Dużą rolę w upowszechnianiu technik jądrowych w identyfikacji i konserwacji obiektów istotnych dla dziedzictwa kulturowego odgrywa Międzynarodowa Agencja Energii Atomowej (MAEA). W artykule omówiono niektóre aspekty zastosowania radiografii w muzealnictwie dyskutowane w trakcie konferencji MAEA zorganizowanej w Narodowym Muzeum Wojny na Malcie.

EN

Radiographic methods make it possible to detect internal and subsurface imperfections in the entire volume of the material using X and gamma rays (γ). In principle, there are no restrictions as to the type of tested objects. The condition is only access to two sides of the irradiated object or structure. An alternative to analog, film radiography techniques is digital radiography. The quality of the image and the absorbed dose are determined by the technology of converting the braking radiation (bremsstrahlung) into a digital signal. Advances in radiography are mainly driven by medical and industrial applications. The new solutions can also be used by art conservators. The International Atomic Energy Agency (IAEA) plays a major role in the dissemination of nuclear techniques in the identification and conservation of objects significant for cultural heritage. The article discusses some aspects of the use of radiography in museology discussed during the IAEA conference organized at the National War Museum in Malta.

2

Development of the technique embedded into a Monte Carlo transport system for calculation of photonuclear isotope yield

Nikiforov V. I., Uvarov V. L.

Nukleonika

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2012

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Vol. 57, No. 1

75-80

EN

The paper describes two methods that use Monte Carlo transport code for computing the photonuclear isotope yield for arbitrary target activation conditions. One of them is based on a direct simulation of new nuclei generation events (DSE method). The other one involves a step-by-step calculation of isotope microyield along the photon trajectories (SBSM method). The techniques have been realized in the computer codes using the PENELOPE package of 2001, 2006 and 2008 versions. The program benchmarking was performed using experimental data on the activity distributions of 67Cu isotope produced in the 68Zn(gamma,p)67Cu reaction in thick zinc targets. Both approaches have shown to give similar results at an appreciably greater speed of the SBSM method. The results of simulation based on the PENELOPE 2006 and 2008 codes are in excellent agreement with all experimental data. At the same time, the PENELOPE 2001 computations give good agreement with the experimental results for target activation by the electron beam, but in the case of target exposed to bremsstrahlung systematic underestimation of about 15% has been observed.

3

Development of diagnostic tools for Plasma Focus derived X-ray source

Angeli E., Bonifazzi C., Da Re A., Marziani M., Tartari A., Frignani M., Mannucci S., Mostacci D., Rocchi F., Sumini M.

Nukleonika

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2006

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Vol. 51, nr 1

15-20

EN

The energy spectra of X-rays generated by the impact of electron beams on high- and medium-Z targets following the pinch implosion of Plasma Focus (PF) devices are discussed in terms of the possible mechanisms of X-ray production following electron impact ionization. In addition, the temperature measurement of the PF inner electrode is reported and some results have been proved useful in order to optimize the device functionalities.

4

Mass throughput rate calculation for X-ray facilities

Ziaie F., Tahami S.

Nukleonika

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2005

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Vol. 50, nr 3

121-124

EN

Abstract In this work, the mass throughput rate in a radiation processing center, equipped with an X-ray facility, is calculated by means of a curve against the thickness of the material, along with the variation of dose uniformity. Therefore, depending on the desired dose value, the best thickness and the mass throughput rate can be calculated. The calculation results for the 5 and 10 MeV X-ray bremsstrahlung for polyethylene and wood as the irradiation products, have been obtained by using a Monte-Carlo computer code. In addition, the experimental results at the same geometry and materials were compared with those calculated.