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Open access

Erol Kam, Iskender A. Reyhancan and Recep Biyik

Abstract

Depending on the neutron energy used, neutron radiography can be generally categorized as fast and thermal neutron radiography. Fast neutron radiography (FNR) with neutron energy more than 1 MeV opens up a new range of possibilities for a non-destructive examination when the inspected object is thick or dense. Other traditional techniques, such as X-ray, gamma ray and thermal neutron radiography, do not meet penetration capabilities of FNR in this area. Because of these distinctive features, this technique is used in different industrial applications such as security (cargo investigation for contraband such as narcotics, explosives and illicit drugs), gas/liquid flow and mixing and radiography and tomography of encapsulated heavy shielded low Z compound materials. The FNR images are produced directly during exposure as neutrons create recoil protons, which activate a scintillator screen, allowing images to be collected with a computer-controlled charge-coupled device camera. Finally, the picture can be saved on a computer for image processing. The aim of this research was to set up a portable FN R system and to test it for use in non-destructive testing of different composite materials. Experiments were carried out by using a fast portative neutron generator Thermo Scientific MP 320.

Open access

Zeki U. Yumun and Erol Kam

Abstract

In this study, the heavy metal and radioactive properties of Iznik Lake were investigated. Concentration values of the first (Ag, Bi, Mo, Sn, Se, Zn, As, B, Cd, Co, Cr, Cu, Ni, Pb, Pt and Sb) and second (Na, Mg, K, Ca, P, S, Fe, Al and Mn) group of elements in borehole 1 (BH-1) drilling did not show much variation from the top to the bottom of the drilling. Concentration values of the first group of elements in borehole 2 (BH-2) drill samples decreased at higher levels of drilling. In addition, natural and anthropogenic radionuclides were measured by gamma spectrometry, and the results of environmental natural radioactivity of Iznik Lake and its surroundings were determined. In the measurement results, Ra-226 was found to be below the world average value at all locations. It is assumed that the determination of K-40 values above the average values was due to agricultural activities carried out intensively in the study area. Th-232 values were found to be below the world average value in drilling samples; Cs-137 values were below the background level in all samples. According to these results, the study area does not contain any unnatural radioactivity.

Open access

Błażej Baic, Beata Kozłowska, Robert Kwiatkowski and Marcin Dybek

Abstract

Photon beams with wide energy ranges from 4 MV to 25 MV are commonly used in radiotherapy nowadays. In recent years, there has been a strong interest in a certain modification of a radiotherapeutic apparatus by the application of the so-called flattening filter-free (FFF) beam. Several advantages of FFF beams over standard flattening filter (FF) beams are noticed, and this technical solution has aroused great interest among radiotherapeutic facilities. The goal of the present study is to investigate the differences between the conventional FF and unflattened FFF 6-MV and 10-MV photon beams in some basic dosimetric parameters and their influence on the whole radiotherapeutic treatment. The data provided here include the detailed characteristics as follows: percent depth dose (PDD), beam profile, edge of a half-profile, total scatter correction factor (TSCF) and head scatter correction factor (HSCF) for FF and FFF 6-MV and 10-MV photon beams from the Elekta Versa HD accelerator in the Katowice Oncology Center in Poland.

Open access

Piotr Darnowski and Michał Pawluczyk

Abstract

This paper presents an analysis of the Benchmark for Evaluation And Validation of Reactor Simulations (BEAVRS) performed using SCALE 6.1.2 and PARCS 3.2 computer codes. The benchmark specification contains a detailed design, operational data and measurements for a real 4-loop Westinghouse pressurized water reactor (PWR). The lattice physics simulations were prepared using TRITON depletion sequence and NEWT neutron transport solver (SCALE package). The 238-neutron group library based on evaluated nuclear data file – ENDF/B-VII nuclear data libraries was applied. A set of branch and burnup calculations was prepared, and group constants in the form of PMAXS files were generated with GenPMAXS. The full-core models were prepared using the PARCS nodal-diffusion core simulator. The PMAXS libraries were used with PARCS to investigate the core operation. The hot zero power measurement data, including control rod worths and critical boron concentrations, were compared using simulations, and satisfactory results were achieved. The first fuel cycle was simulated, and acceptable agreement with boron letdown curve and measurements were obtained. Finally, conclusions and recommendations for future research were presented.

Restricted access

O. Atolani, O.S. Adeyemi, F.O. Agunbiade, O.S. Asaolu, E. Gayawan, T.G. Jaiyeola, M.R. Usikalu and E. I. Unuabonah

Open access
Open access

Andrzej G. Chmielewski and Marcin Sudlitz

Abstract

Large quantity of sewage sludge originating from wastewater treatment plants is becoming a growing problem from environmental and human health points of view. One of the ways to use sewage sludge is agricultural purpose due to its nutrients and organic matter content, but the condition is that it should be deprived of pathogenic bacteria and parasite egg contamination. Application of ionizing radiation to hygienize sewage sludge can make it appropriate for agricultural use. The process does not require addition of chemicals to sludge; it is environmentally friendly and effective in removal of biological threats. In the past, successful attempts of sewage sludge treatment using ionizing radiation were made. Pilot plants and commercial ones proved that pathogens can be easily removed from sewage sludge by ionizing radiation. The concept of ‘zero energy’ biogas plant is based on the construction of a complex system consisting of biogas plant and electron accelerator in the biofertilizer manufacturing line. Digestate originating from the methane fermentation of sewage sludge is irradiated to remove all pathogens using electron beam from an accelerator powered by electric energy obtained from burning biogas in a cogenerator. The product is a high-quality, biologically safe fertilizer.

Open access

Oluwatoyin T. Fatunsin, Oluwasegun T. Adetunde and Kehinde O. Olayinka

Abstract

Cancer is on the increase globally. Cancer could be associated with hazards from anthropogenic activities. This study attempted to determine the site-specific potential human risks from polycyclic aromatic hydrocarbons (PAHs) in sites of different socioeconomic human activities from soils across Lagos metropolis in Nigeria by including a geographic information system (GIS) approach. A Human Simulation Test method was used to determine bio-accessibility for 16 priority PAHs. This was then spatially modelled using a GIS. The spatial vulnerability index for cancer developed show some variation within the study area from 0.2 – 0.0002 all falling below the normal exposure risk level of 1.0. The vulnerability to cancer based on different anthropogenic activities assessed were within the acceptable risk levels. However, it is important to reduce human exposure to even low concentrations of bio-accessible PAHs due to their tendency to bio-accumulate in plants, humans and other organisms.

Open access

Stefan Demcak, Magdalena Balintova, Maria Demcakova, Inga Zinicovscaia, Nikita Yushin and Marina V. Frontasyeva

Abstract

The heavy metal removal from wastewater is very important due to their persistent character in aquatic environment. The use of wooden sawdust is emerging as a potential alternative to the existing conventional technologies for the removal of metal ions from aqueous solutions. The aim of this work is to study the Cu(II) removal of from water by unconventional waste products including the wooden sawdust of poplar, cherry, spruce and hornbeam. The FT-IR spectra of the studied wooden sawdust confirmed the presence of functional groups that have potential for heavy metal binding. The highest efficiency of Cu(II) removal was observed for poplar wooden sawdust at static (86 %) and dynamic (88 %) adsorption experiments. Data obtained by neutron activation analysis revealed that ion exchange is also a mechanism of metal removal by the selected wooden sawdust.

Open access

Giurma-Handley Catrinel-Raluca, Telișcă Marius and Paerele Cosmin-Marian

Abstract

The concept of sustainable development resulted from the conciliation of three aspirations: economic and social development, protection of the state of environment and increasing the importance of environmental policies. In order to protect the water quality, the catchments are arranged by organizational, agricultural and technical measures and works that need to be applied both on the slopes and in the drainage network. The paper presents new concepts of authors to limit the liquid and solid runoff that could affect water quality as an indispensable factor for life.