Neutron and gamma radiation shielding properties
Precio : Gratis
Publicado por : dfsdsdsr
Publicado en : 26-10-21
Ubicación : London
Visitas : 26
Sitio web : http://www.nuclear-shield.com/
Neutron and gamma radiation shielding properties
High performed new heavy concrete samples were designed and produced that absorption parameters were
determined for gamma and neutron radiation by using Monte Carlo Simulation program GEANT4 code. In the sample
production, many different materials were used such as; chromite (FeCr2O4), wolframite [(20Fe,80Mn) WO4], hematite
(Fe2O3), titanium oxide (TiO2), aluminum oxide (Al2O3), limonite (FeO (OH) nH2O), barite (BaSO4), materials.
Furthermore, calcium aluminate cement (CAC) was utilized for high temperature resistant. In the current study,
five different new heavy concrete samples were produced then physical and chemical strength of them tested. High-
temperature-resistant tests were made at 1000°C and good resistance against high temperature was observed.
Neutron equivalent dose measurements were made for by using 4.5 MeV energy 241Am-Be fast neutron source. Results
compared with paraffin and conventional concrete. It was found that the new heavyweight concretes had the better
absorption capacity than paraffin and conventional concrete. Gamma radiation absorption measurements also were
carried out at the energies of 160, 276, 302, 356, and 383 keV by using 133Ba point radiation source. It has been
suggested that the new produced concretes can be used for radiation safety in the nuclear applications.
Radiation is often used in applications such as in energy production, in medicine diagnosis and treatment, in
material research and investigation. In addition, it is also used in such areas as agriculture, archeology (in
carbon determination), space exploration, military, geology, and many others (U.S. NRC, 2010). Radiation leaks may
occur during these applications (Lamarsh, & Baratta, 2001); therefore, it must be properly shielded. In radiation
shielding works, conventional materials such as concrete, steel, alloy, ceramic, glass, and polymers are widely
used (Aygün et al., 2019; Kumar, Sayyed, Dong, & Xue, 2018; Sayyed, Akman, Kumar, & Ka?al, 2018). In these
studies, concrete is among the most widely used materials (Li et al., 2017). Concrete is a composite material
which glued in such a way that aggregate particles (sand, gravel, stone, and filler) with cement or a binder.
Traditional concrete is not as effective in nuclear
shielding material radiation, but it is a very common used building material. The traditional concrete
lead
bricks for radiation shielding characteristic may vary and is dependent on the chemical composition of the
concrete. New types of concrete samples have been developed by different the aggregated used for preparing
concrete, depending on the available natural and artificial materials (Mukhtar, Shamsad, Al-Dulaijan, Mohammed, &
Akhtar, 2019; Chen, 1998). Heavy concrete is the most common material used in radiation shielding equipment. Heavy concrete is obtained by
adding high-density aggregates into normal concrete. Normal-weight concrete density varied between 2200 and 2450
kg/m3 while heavy concrete’s density is ranging from about 2900 and 6000 kg/m3 (Nawy, 1997). Some natural
minerals such as hematite, magnetite, limonite, serpentine, siderite and barite can be used as aggregates in heavy
concrete production. In literature, numerous experimental and theoretical researches have been conducted to
develop new heavy concrete. Different minerals like siderite, limonite were used to produce heavy concrete in
order to provide gamma radiation shielding. It was reported that the gamma radiation absorption capacity of heavy
concretes is high (Basyigit et al., 2011). Boron-containing multi-layered new heavy concretes were produced and
radiation shielding properties were determined. It is reported that these concretes are very high in 14 MeV
neutron absorption capacity (Sato, Maegawa, & Moshimatsu, 2011). In a different study, some metal oxides such as
Al2O3, AS2O3, BaO, CaSO4, CdO, Cr2O3, CuO, Fe2O3, K2O, MgO, MnO, Na2O, NiO, P2O5, PbO4, SrO, TiO2 was used in the
heavy concrete production, and it was stated that the use of these new heavy concretes in nuclear reactors is
appropriate (Abdo, 2002; Erdem, Baykara, Do?ru, & Kulu?ztürk., 2010; Mortazavi, Mosleh-Shirazi, & Baradaran
Ghahfarokhi et al., 2010). Seltborg et al.produced heavy concretes by using, such as calcium (Ca), strontium (Sr),
barium (Ba), radium (Ra) magnesium (Mg) elements. They determined these heavy concretes can be used to shield
gamma and neutron radiation in nuclear reactors (Seltborg et al., 2005). In the present study of tungsten oxide
(WO3) gamma radiation mass attenuation coefficient in the concrete, the effect on the coefficient was
investigated. Appropriate geometry found by using MCNPX and XCom simulation programs. It is found that shielding
properties when nanoparticle WO3 doped in concrete more than microparticle WO3 (Tekin, Singh, & Manici, 2017). In
another study, high-density concrete (ρ = 4.71 g/cm3) was made by using steel balls and in aggregate the debris
of the demolished concrete buildings in the earthquake region in Fukushima. Good shield properties were determined
this of heavy concrete and it is shown that can be used in storage radioactive waste (Sanjay, Yusuke, Kimura,
Fujikura, & Araki, 2018). Heavy concrete was made using lead-zinc slag waste instead of sand which can be used
gamma radiation shielding. Shielding and strength properties were investigated of this concrete and compared with
conventional concrete. It is reported that lead–zinc slag waste concretes better radiation shielding and strength
characteristic than conventional concretes (Mohamed, 2017). Medical cyclotron is a system designed for
radiopharmaceutical production, which high-level radiation emit. Shielding wall thickness was calculated by using
Monte Carlo simulation when cyclotron system used to operate that may occur radiation. Consequently, for
shielding, radiation at 200-cm-thickness concrete wall need was determined (Jang, Kim, & Kim, 2017). Some mining
wastes suitable for heavy concrete production. For instance, Gallala et al. have produced new heavy concrete by
using barite-fluorspar mine waste (BFMW) aggregates and investigated their gamma radiation shielding, mechanical
strength properties. The results clearly showed when ratio 25% BFMW added to concretes has better gamma radiation
shielding and compressive strength properties than conventional concrete (Gallala et al., 2017). Tekin et al.,
using MCNPX code, demonstrated that high strength concrete containing nanoparticles of WO3 and Bi2O3 had enhanced
shielding capacity for gamma radiation (Tekin, Sayyed, & Issa, 2018). Five different concrete types were made
using magnetite aggregates and 0%, 2%, 4%, 6%, and 8% of titanium dioxide (TiO2) nanoparticles for nuclear power
plant shielding material. Some of the protecting parameters such as MAC (mass attenuation coefficients) HVL
(half-value layer), TVL (tenth value layer), and linear attenuation coefficients (LAC) were determined for 662,
1173, and 1332 ?keV energy of gamma ray used. It is reported, the significant effect on radiation shielding
properties occurred within 8% of TiO2 nanoparticles (Iman et al., 2019). Some natural minerals can be using heavy
concrete in production. Different concrete types which including natural perlite mineral and B4C have been
experimentally investigated and gamma radiation shielding parameters have been determined (Agar et al., 2019)
In this study, new concrete samples were designed and produced using Monte Carlo simulation program Geant4
code. The production of heavy concrete for radiation shield was made based on the concrete production process such
as mixture proportion, ratio of water to cement, cement hydration. Furthermore, new concrete candidates with good
radiation shielding
ability at high temperature have been produced and it has been shown that raw materials such as chromite,
wolframite can be used in production.
In Monte Carlo simulation program, the Geant4 code is used to determine the interactions between radiation and
materials. In addition, it can be used to predict nuclear events that may occur at the point of radiation and
detector interaction. Geant4 software is the most developed, for analyses biological effects of radiation-induced
and their modification nuclear shielding
engineering. Also, Monte Carlo program Geant4 to simulate can be used to predict the transport, accumulation
of incident particles through the walls of a nuclear power plant (Agostinelli et al., 2003). It is used in
applications in nuclear physics, particle accelerator designing, space investigation, and medical physics.
Detailed information can be found at www.Geant4.org.
2.2. Sample preparation
New heavy concrete samples were produced by using different natural aggregates such as chrome ore (FeCr2O4),
wolframite [(Fe,Mn)WO4], hematite (Fe2O3), limonite (FeO (OH) nH2O), barite (BaSO4). Nickel oxide (NiO) was used
to fill the pores that could form in the concrete. The chromium ore (FeCr2O4) mineral has a density of average
4.79 g/cm3 and it melts in temperature 1650–1660°C (Jay, Meegoda, Zhengbo, & Kamolpornwijit, 2007). The chrome
ore sample was taken from the Kayseri city Yahyal? district chrome mine. This chrome ore contains such minerals
53.19% Cr2O3, 16.80% MgO, 11.15%Al2O3, 15.11%Fe, 2.72%SiO2, 0.007%S, and 0.005% P according to Eti (Chromium
Ferrochrome Foundation). Wolframite is a mineral with a density of 7.1–7.5, average 7.3 g/cm3 and 11.70% MnO,
16.85% FeO, 71.46% WO3 including (Tolun., 1951). This ore was obtained from an Uluda? tungsten mine, which is
located in the province of Bursa and is approximately 2200–2300 m high from the sea. According to the pioneering
simulation work, both gamma and neutron radiation absorption cross-sectional values were determined higher in
chromite and wolframite minerals. Furthermore, these minerals have both refractory properties and high mechanical
strength and plenty of reserves. Therefore, these minerals were used in the production of heavy concrete.
Hematite, titanium oxide, aluminum oxide, limonite, siderite, barite, materials are always used materials for the
production of heavy concrete, but for that, the chromite and wolframite minerals are not very commonly used. The
usage of natural chromite and wolframite minerals provided will be with this work in the nuclear industry.
Chromium oxide (Cr2O3) was used to fill capillary cavities that may form in concretes. When concrete components
were selected, the high macroscopic cross-sectional values were taken into account.