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Considering that people spend most of their time in buildings (home, office, school, shopping mall, etc.), it is seen that the radiation retention properties of building materials are important. Nuclear power plants are a complex of structures that are of great importance in today's energy-age world, but also bring some dangers. The most important of these dangers is the possibility of radiation leakage from these structures in the event of an explosion. In addition, shielding for radiation protection is important in medical applications and industry where radiation is widely used. Therefore, the strength and durability properties of concretes to be used in the construction of nuclear power plants need to be meticulously designed. All this shows how important and worthy of research the subject of the study is. For this purpose, new materials that are easy to access, abundant and cheap, and have high absorption capability are needed, rather than shield made only of lead materials. Perlite, pumice and Ahlat stones are abundant in Bitlis (Turkey) province and are extracted from the quarries. The bims block samples (B-1, B-2 and B-3) produced in factories in Bitlis. This study was carried out to investigate whether these materials, which are used as building materials, have radiation absorbing properties in terms of their use in different areas. Linear attenuation coefficients were calculated experimentally for gamma energies at 88.04 ± 0.01 keV, 356.50 keV, 661.60 keV, 834.80 ± 0.04 keV and 1173.20–1332.50 keV (for 109Cd, 133Ba, 137Cs, 54Mn and 60Co radioactive point sources) using gamma spectrometry with a NaI scintillation detector. In addition, photon absorption percentages, half value layer (HVL), tenth value layer (TVL) and mean free path (MFP) values of the samples were calculated. The obtained data were evaluated by comparing with similar studies in this field and the results obtained for lead shield. As a result of the study, it is seen that instead of using perlite and pumice alone, it is better radiation trap when they are mixed with each other and formed into bims blocks. • Gamma-ray linear attenuation coefficients were determined by using gamma sources in NaI(Tl) scintillation detector. • HVL, TVL, MFP values of Ahlat stones, perlite, pumice and bims block samples were calculated. • Analysis results for B-1, B-2 and B-3 samples are higher than those obtained for pure pumice. • The B-3 sample may be preferred for radiation shielding at very high energies. • The results obtained for the B-1 sample are close to the results obtained in similar studies for lead at 662 keV. [ABSTRACT FROM AUTHOR]

Neutron scattering in combination with scanning electron and atomic force microscopy were employed to quantitatively resolve elemental composition, nano- through meso- to metallurgical structures and surface characteristics of two commercial stainless steel orthodontic archwires—G&H and Azdent. The obtained bulk composition confirmed that both samples are made of metastable austenitic stainless steel type AISI 304. The neutron technique’s higher detection sensitivity to alloying elements facilitated the quantitative determination of the composition factor (CF), and the pitting resistance equivalent number (PREN) for predicting austenite stability and pitting-corrosion resistance, respectively. Simultaneous neutron diffraction analyses revealed that both samples contained additional martensite phase due to strain-induced martensite transformation. The unexpectedly high martensite content (46.20 vol%) in G&H was caused by combination of lower austenite stability (CF = 17.37, p = .03), excessive cold working and inadequate thermal treatment during material processing. Together, those results assist in revealing alloying recipes and processing history, and relating these with corrosion resistance and mechanical properties. The present methodology has allowed access to unprecedented length-scale (μm to sub-nm) resolution, accessing nano- through meso-scopic properties. It is envisaged that such an approach can be extended to the study and design of other metallic (bio)materials used in medical sciences, dentistry and beyond.

This study uses building blocks as a shield for gamma energy source of 662 KeV from Cs-137. The attenuation from the block is compared with those obtained when conventional shields like iron, lead and concrete are used as shield for Cs-137. This was done with the aim of finding out the level of shielding and the thickness of building block needed to confer same level of shielding as the already mentioned conventional shields. The results obtained using a gamma spectrometer with a NaI(Tl) detector showed that the Half Value Thickness (HVT) of building block, concrete, iron and lead were 5.1420 cm, 3.8043 cm, 1.1908 cm, and 0.5581 cm respectively. With the results from this work, a shield of 37 cm building block (though bulky in size) will attenuate the source and can be used as a substitute for lead which would require a 4.4 cm thickness. [ABSTRACT FROM AUTHOR]

Hafnium Oxide nanoparticles have been synthesized by precipitation method and analyzed for its structural, Morphological and dosimetric properties. The structural and morphological properties are examined by utilizing XRD and FESEM. The investigation of dosimetric parameter has been carried out with the usage of annealing and thermal quenching of HfO 2 NPs. The monoclinic phase arrangements of HfO 2 with space group [P21/c] were well characterized by retiveld refinement and PXRD pattern. From FESEM and EDS studies it is observed that the estimated size of NPs is 58 nm, spherical in shape and the Hf/O proportion are found to be 0.4211, The heating rate of HfO 2 are Optimized by studying the glow curve for various heating rate and Optimized at 10 °C/s and the annealing temperature has been carried out for 10 °C/s heating rate by varying the temperature and time and optimized to 300 °C at 30 min. The dosimetric parameters such as ECF, CV, Batch homogeneity, photo dose-linearity and reproducibility were studied using 60Co beam. Hence the observed results clearly indicates that the HfO 2 NPs can be utilized as dosimetric material in the application of Radiotherapy and it can be effectively used in Radiation dosimetry especially for Neutron dosimetry. • HfO 2 nanoparticles have been synthesized by Precipitation method. • Structural and morphological characteristics have been studied. • Various dosimetric parameter have been analyzed. [ABSTRACT FROM AUTHOR]

Neutron scattering in combination with scanning electron and atomic force microscopy were employed to quantitatively resolve elemental composition, nano- through meso- to metallurgical structures and surface characteristics of two commercial stainless steel orthodontic archwires—G&H and Azdent. The obtained bulk composition confirmed that both samples are made of metastable austenitic stainless steel type AISI 304. The neutron technique's higher detection sensitivity to alloying elements facilitated the quantitative determination of the composition factor (CF), and the pitting resistance equivalent number (PREN) for predicting austenite stability and pitting-corrosion resistance, respectively. Simultaneous neutron diffraction analyses revealed that both samples contained additional martensite phase due to strain-induced martensite transformation. The unexpectedly high martensite content (46.20 vol%) in G&H was caused by combination of lower austenite stability (CF = 17.37, p =.03), excessive cold working and inadequate thermal treatment during material processing. Together, those results assist in revealing alloying recipes and processing history, and relating these with corrosion resistance and mechanical properties. The present methodology has allowed access to unprecedented length-scale (μm to sub-nm) resolution, accessing nano- through meso-scopic properties. It is envisaged that such an approach can be extended to the study and design of other metallic (bio)materials used in medical sciences, dentistry and beyond. [ABSTRACT FROM AUTHOR]