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Osłony elastomerowe redukujące dawki promieniowania X w technikach tomografii komputerowe

Kusiak E., Zaborski M., Staniszewska A., Bem H., Szajerski P., Baryń W.

Polimery

2013

T. 58, nr 7-8

519--523

Opracowano bezołowiowe osłony redukujące dawki promieniowania w diagnostyce technikami tomografii komputerowej. Podstawę stanowiła matryca z kauczuku naturalnego napełnionego tlenkami: bizmutu, wolframu lub gadolinu. Ze względu na generowanie przez bizmut wtórnego promieniowania fluorescencyjnego rozszerzono pierwotne składy kompozytów. Stwierdzono, że otrzymane kompozyty kauczuku naturalnego zawierające kombinacje tlenków metali charakteryzowały się dużymi wartościami masowych współczynników pochłaniania, wpływały na redukcję natężenia promieniowania padającego o energii: Eg = 60 keV o ok. 50 % a o energii Eg = 122 keV o ok. 20 %. Jednocześnie prawie wszystkie próbki wulkanizatów wykazywały korzystne właściwości wytrzymałościowe.

We have developed lead-free shields reducing the radiation doses in the diagnostic computed tomography techniques. They are based on natural rubber matrix with oxides of bismuth, tungsten and gadolinium as fillers. Due to the generation of secondary fluorescence radiation by bismuth, the study was extended to other compositions. The obtained natural rubber composites containing the combinations of metal oxides were characterized by high values of the mass absorption coefficient, which effected in the reduction in the intensity of incident radiation with an energy Eg = 60 keV by about 50 % and for Eg = 122 keV by about 20 %. It should be noted that virtually all vulcanizates showed good strength properties.

A comparison of selected natural radionuclide concentrations in the thermal groundwater of Mszczonów and Cieplice with deep well water from Łódź city, Poland

Grabowski P., Długosz M., Szajerski P., Bem H.

Nukleonika

2010

Vol. 55, No. 2

181-185

A simple procedure using α and γ spectrometry for the determination of natural radionuclides in two Polish geothermal water samples from Mszczonów and Cieplice, as well as in deep well groundwater from the city of Łódź, was described. The 222Rn radionuclide was directly extracted from 10 cm3 water samples to a scintillator solution placed in scintillation vials and determined by an liquid scintillation (LSC) technique with α/β separation. The activity concentrations of three radium nuclides: 228Ra(228Ac), 226Ra(222Rn), 224Ra, as well as 210Pb and 228Th were measured by γ spectrometry with an HPGe detector after their preconcentration on hydrated MnO2. 210Po was deposited on a silver disc from dissolved MnO2 precipitate after γ-spectrometry analysis and measured by α spectrometry. The concentration of 210Pb in the examined samples was below the detection limit of the method (< 6.2 mBq/dm3), whereas activity of its decay product 210Po was in the range 0.35–1.4 mBq/dm3. Higher activities of 228Ra (46.7 mBq/dm3), 226Ra (67.8 mBq/dm3) and 224Ra (22.4 mBq/dm3) were observed for the deep well water in Łódź in comparison to those for geothermal water samples from Cieplice and Mszczonów. However, concentrations of all the measured radionuclides were below World Health Organization (WHO) reference activities (0.1 Bq/dm3 for 228Ra and 1 Bq/dm3 for 226Ra and 226Ra).