Field Of Radiation Protection Research Articles

Monte Carlo modelling of cyclotron and radioisotope center (CYRIC) at Tohoku University: a radiation protection study

Protection against ionizing radiations is important in laboratories with radioactive materials and high energy cyclotron beams. The Cyclotron and Radioisotope Center (CYRIC) located in Tohoku University in Miyagi prefecture, Japan and is a well-known nuclear science laboratory with cyclotron beams and substantial number of high activity radioactive materials. Considering this, it is important to perform complete radiation transport computations to ensure the safety of non-occupational and occupational workers. In the present work, we have developed a complete 3-dimensional model of the main cyclotron building and radiation labs using Monte Carlo method. We have found that the dispersed photons and neutrons inside and in the surrounding of the CYRIC building pose no significant risk to occupational and non-occupational workers. The present work and the developed models would be useful in the field of radiation protection.

The impact of dose rate on responses of human lens epithelial cells to ionizing irradiation

The knowledge on responses of human lens epithelial cells (HLECs) to ionizing radiation exposure is important to understand mechanisms of radiation cataracts that are of concern in the field of radiation protection and radiation therapy. However, biological effects in HLECs following protracted exposure have not yet fully been explored. Here, we investigated the temporal kinetics of γ-H2AX foci as a marker for DNA double-strand breaks (DSBs) and cell survival in HLECs after exposure to photon beams at various dose rates (i.e., 150 kVp X-rays at 1.82, 0.1, and 0.033 Gy/min, and 137Cs γ-rays at 0.00461 Gy/min (27.7 cGy/h) and 0.00081 Gy/min (4.9 cGy/h)), compared to those in human lung fibroblasts (WI-38). In parallel, we quantified the recovery for DSBs and cell survival using a biophysical model. The study revealed that HLECs have a lower DSB repair rate than WI-38 cells. There is no significant impact of dose rate on cell survival in both cell lines in the dose-rate range of 0.033–1.82 Gy/min. In contrast, the experimental residual γ-H2AX foci showed inverse dose rate effects (IDREs) compared to the model prediction, highlighting the importance of the IDREs in evaluating radiation effects on the ocular lens.

Investigation of borate glasses reinforced with iron (III) oxide [Fe2O3]: Preparation, physical, UV–Vis properties and γ-ray attenuation efficacy

Five samples of borate glasses reinforced with various ratios of Fe3+ ions with chemical formula (60-X)B2O3–10ZnO–10CdO–5Li2O–15Na2O-XFe2O3: (0.0 (Fe-0.0) ≤ X ≤ 1 (Fe-1.0) mol%) were prepared using the melt-quenching technique. The structure, physical, optical characteristics, and γ-ray attenuation properties of the prepared Fe-X glasses have been investigated. The amorphous state of Fe-X glasses confirmed by XRD observations. Density (ρglass) of the Fe-X glasses increased from 3.21 g cm−3 to 3.91 g cm−3. Molar volume (Vm) gradually reduced from 18.87 cm3/mol to 15.35 cm3/mol with increasing Fe2O3 content in the glass network from 0.0 to 1.0 mol%. The color of Fe-X glasses changed from yellow to brown according to the absorption bands located at around 385–412 nm and 407–429 nm within the visible spectrum. The indirect optical band gap (Eg) decreased from 3.37 eV to 2.78 eV, while the linear refractive index (no) increased from 2.31 to 2.45. Mass- (MAC) and linear- (LAC) attenuation coefficients increased as Fe3+ ions increased in the glass network. The Fe-1.0 sample with highest Fe2O3 content possessed the lowest values of half-value layer (HVL) and mean free path (MFP) shielding parameters. Results revealed that the suggested glass compositions can be applied in optical and radiation protection fields.

Isostatic hot-pressed tungsten radiation shields against gamma radiation

An isostatic hot-pressing technique for the fabrication of dense W samples' is presented. The samples’ microstructure and chemical content were analyzed. The most compact samples were received at 5 GPa pressure and 1500 and 2000 °C temperatures, with densities of 18.50 and 19.07 g/cm3, respectively. It has been established that high temperature exposure has a positive effect on both the microstructure and density. It is shown that as the sintering temperature increases, the porosity of the samples decreases from 32.31% to 0.94%, and their relative density increases from 67.69% to 99.06%. The crystal structure investigation revealed that all the samples contain the main body-centered cubic W phase, and the availability of the WO2 phase is observed just after the temperature of sintering increases above 1000 °C, which is confirmed by the appearance of 111 and 22-2 reflections. A study of the shielding effectiveness against gamma-radiation was carried out using the Phy-X/PSD software. A gamma-ray source of Co60 with energies of 0.8–2.5 MeV was applied for the calculations. The results were calculated for the sample with the highest density (19.07 g/cm3) and compared with the calculations for Pb. The W shielding effectiveness main parameters are determined: linear attenuation coefficient (at 0.8 MeV–1.46 cm-1), mean free path (at 2.5 MeV–1.2 cm) and half value layer (at 2.5 MeV–0.86 cm). These values turned out to be higher than for Pb, which makes shields based on W promising for use in the field of radiation protection.

Novel composite based on silicone rubber and a nano mixture of SnO2, Bi2O3, and CdO for gamma radiation protection

Recently, there has been a surge of interest in the application of radiation-shielding materials. One promising research avenue involves using free-lead metal oxides/polymer composites, which have been studied for their radiation shielding and characterization properties. This study reinforced the dimethylpolysiloxane (silicone rubber) composites with micro- and nano-sized particles of tin oxide, cadmium oxide, and bismuth oxide as additive materials. The composites were tested with 20 and 50 weight fractions, and their attenuation coefficients were measured using a NaI(TI) detector at gamma-ray energies ranging from 59.54 to 1408.01 keV. Also, the thermal and mechanical properties of the composites were observed and compared with those of free silicone rubber. The results showed that the 50% nano metal oxide/SR composites exhibited better thermal stability and attenuation properties than the other composites, also possessing unique attributes such as lightweight composition and exceptional flexibility. Consequently, this composite material holds immense potential for safeguarding vital organs, including the eyes and gonads, during radiological diagnosis or treatment procedures. Its exceptional ability to absorb a significant portion of incident rays makes it an invaluable asset in the field of radiation protection.

Physical, mechanical, and microstructural characterisation of tungsten carbide-based polymeric composites for radiation shielding application

Polymeric based composites have gained considerable attention as potential candidates for advanced radiation shielding applications due to their unique combination of high-density, radiation attenuation properties and improved mechanical strength. This study focuses on the comprehensive characterisation of polymeric based composites for radiation shielding applications. The objective of this study was to evaluate the physical, mechanical and microstructural properties of tungsten carbide-based epoxy resin and tungsten carbide cobalt-based epoxy resin for its efficiency in shielding against gamma-rays ranging from 0.6 up to 1.33 MeV. Polymeric composites with different weight percentages of epoxy resin (40 wt%, 35 wt%, 30 wt%, 25 wt%, 20 wt%, 15 wt% and 10 wt%) were fabricated, investigated and compared to conventional lead shield. The attenuation of the composites was performed using NaI (Tl) gamma-ray spectrometer to investigate the linear and mass attenuation coefficients, half value layer, and mean free path. High filler loadings into epoxy resin matrix (90% filler/10% epoxy) exhibited excellent gamma shielding properties. Mechanical properties, such as hardness were examined to assess the structural integrity and durability of the composites under various conditions. The fabricated composites showed a good resistance, the maximum hardness was attributed to composites with small thickness. The high loading of fillers in the epoxy matrix improved the microhardness of the composites. The distribution of the filler powder within the epoxy matrix was investigated using FESEM/EDX. The results revealed the successful incorporation of tungsten carbide and cobalt particles into the polymer matrix, leading to increased composite density and enhanced radiation attenuation. The unique combination of high-density, radiation attenuation, and improved mechanical properties positions polymeric based composites as promising candidates for radiation protection field.

Study on neutron–gamma discrimination method based on the KPCA-GMM

Neutron–gamma discrimination plays a fundamental role in the fields of radiation protection and nuclide identification. In this paper, the neutron–gamma discrimination algorithm based on the combination of the kernel principal component analysis (KPCA) and the gaussian mixture model (GMM) was studied. The EJ309 liquid scintillation detector was used to detect two radioisotope neutron sources (252Cf and 241Am-Be). KPCA was used to reduce the dimension of the characteristic value of the pulse signal, GMM was used to cluster the dimensionality reduction results. The suitability of silhouette coefficient (S) as a discriminating index of traditional method and machine learning method was studied. The KPCA-GMM was compared with charge comparison method (CCM) and frequency gradient method (FGA) by using silhouette coefficient. The results show that the KPCA-GMM has higher discrimination accuracy. In the radiation field of 252Cf and 241Am-Be, the S of the KPCA-GMM reached 0.91 and 0.93, which were higher than those of CCM (0.86 and 0.86) and FGA (0.85 and 0.84). Therefore, the KPCA-GMM has good generalization ability and can be used for neutron–gamma discrimination.

Strengths of ecosystem services concept for radiation protection.

The successful ecosystem services concept, defined as the benefits people obtain from ecosystems is still not really reflected in the current approaches for protecting public and environment against radiation promoted by the International Commission on Radiological Protection or other similar approaches. Yet some recent thoughts from international organizations lead us to believe that an eco-based approach could be more promoted in the coming years in environmental radiation protection field. The French Institute for Radiation Protection and Nuclear Safety has identified different fields of application of this concept into radiation protection, in line with its integrated approach of radiological risks management. As the ecosystem services approach makes it possible to highlight biophysical and socio-economic approaches of the impacts of ionizing radiation on ecosystems, it represents a subject of primary importance for future works conducted by IRSN. However, the operationality of the ecosystem services concept is the subject of many debates. In many situations, scientists have not yet fully understood how radioactive contamination could affect ecosystem services, and how to articulate with certainty cause and effect relationships between state of an ecosystem and provision of services. In addition, the concept is also accompanied by contradictory perceptions of the status of humans in ecosystems. To solve these knowledge gaps and uncertainties, it is necessary to acquire robust data on the impacts of radiation on ecosystems both under experimental and realistic conditions, and to integrate all potential consequences (direct and indirect, ecotoxicological but also economic and cultural).

Radiation-induced bystander effect and its clinical implications.

For many years, targeted DNA damage caused by radiation has been considered the main cause of various biological effects. Based on this paradigm, any small amount of radiation is harmful to the organism. Epidemiological studies of Japanese atomic bomb survivors have proposed the linear-non-threshold model as the dominant standard in the field of radiation protection. However, there is increasing evidence that the linear-non-threshold model is not fully applicable to the biological effects caused by low dose radiation, and theories related to low dose radiation require further investigation. In addition to the cell damage caused by direct exposure, non-targeted effects, which are sometimes referred to as bystander effects, abscopal effects, genetic instability, etc., are another kind of significant effect related to low dose radiation. An understanding of this phenomenon is crucial for both basic biomedical research and clinical application. This article reviews recent studies on the bystander effect and summarizes the key findings in the field. Additionally, it offers a cross-sectional comparison of bystander effects caused by various radiation sources in different cell types, as well as an in-depth analysis of studies on the potential biological mechanisms of bystander effects. This review aims to present valuable information and provide new insights on the bystander effect to enlighten both radiobiologists and clinical radiologists searching for new ways to improve clinical treatments.

Recycled hybrid material for use as shielding in operations with ionizing radiation

One of the most efficient measures to prevent gamma radiation is shielding, which can take the form of protection barriers, storage containers, wall coating, bunkers, or many others aimed at minimizing the exposure of people to radiation. The materials used to this end have not changed much since the invention of X-rays, when materials with high attenuation capacity were employed, such as lead, tungsten, or concrete. These are all high-density materials and, therefore, also very heavy, and some of them are expensive and not environmentally friendly, as they do not have many possibilities with regards to their recycling. Circular economy provides an opportunity to reintroduce subproducts and waste in the same production processes that generated them or as raw matters in others. The use of sustainable materials is one of these options; however, there is little research in the field of radiation protection about the use of recycled material to this end, and there are few alternative sustainable options different from conventional materials that show similar behaviour. In our study, we have designed and built shielded panels called Mixlead® for gammagraphy, made of 100 % recyclable materials with sandwich structures combining polymeric fractions of electric cables and lead-alloy protection sheets used in the packaging of radiographic plates. With a methodology combining shielding calculations and a series of thermomechanical-radiological tests, it was possible to accurately determine the thickness of Mixlead® necessary to perform the tests with security guarantees and meeting sustainability requirements for radioactive sources of Iridium (192Ir) and Selenium (75Se), the use of the former being predominant, with an average activity of 1 GBq. In order to reduce this activity 2 and 10 times, the necessary thickness would be 24 and 79 mm respectively, which represents 3 or 4 layers of Mixlead® material.

Assessing the Level of Knowledge, Attitude, and Performance of Radiographers About Radiation Protection in Bandar Abbas, Iran

Background: Although radiography tests are beneficial in diagnosing various diseases, they have some risks for patients and radiology staff, which will be minimized if observing radiation protection standards. The purpose of this study was to evaluate the knowledge, attitude, and performance of radiographers regarding radiation protection in the radiology departments of Bandar Abbas. Methods: This work was performed as a descriptive-analytical study. A questionnaire consisting of 38 items was distributed among all radiographers in Bandar Abbas. Information obtained from the questionnaires was analyzed by appropriate nonparametric tests and Spearman’s correlation coefficient. The Kolmogorov-Smirnov test was used to normalize the distribution of scores. Finally, linear regression was employed to determine the effect of each independent variable on the knowledge score. Results: The participation rate of radiographers was 53.9%. The means and standard deviations of scores assigned to attitude, knowledge, and performance in the field of radiation protection were 65.36±27.11, 36.36±17.72, and 46.66±19.60, respectively. The relationship between age and experience of radiographers with their attitude, knowledge, and practice was significant (P>0.05). In addition, there was a significant difference between their attitudes in terms of the place of service (P<0.05). Conclusion: The results of this study revealed that radiographers with different levels of age, education, and work experience have almost the same level of knowledge, attitude, and practice. They had an appropriate attitude and practice in the field of radiation protection.

Clinical capability of Iranian operating room nurses and surgeons regarding radiation protection protocols in radiation-exposed operating rooms

Background: Considering the daily increasing use of radiation in operating rooms and the existing problems in the field of radiation protection, the present study aimed to evaluate the clinical capability of operating room nurses and surgeons regarding radiation protection protocols in radiation-exposed operating rooms in Shiraz. Methods: This descriptive, cross-sectional study was carried out in 2019–2020 by conducting a census of radiation-exposed nurses and surgeons in the operating rooms of private and public hospitals in Shiraz. The study data were collected using a demographic and professional information form and a questionnaire on the radiation protection capability of operating room personnel. Then, the data were entered into the SPSS 25 software and were analyzed via descriptive and inferential statistics. Results: Totally, 200 questionnaires were completely filled out. The mean age of the participants with complete questionnaires was 33.34 ± 8.09 years. The mean scores of clinical capability, knowledge, attitude, performance, and personal commitment were 111.7 ± 21.09, 39.05 ± 12.8, 44.2 ± 7.2, 14.6 ± 6.2, and 13.98 ± 5.8, respectively. Accordingly, the participants’ knowledge, attitude, personal commitment, and clinical capability were at good levels, while they showed a weak performance. Conclusion: It seems that educational as well as managerial measures in terms of radiation protection protocols are needed to increase the clinical capability of radiation-exposed operating room nurses and surgeons. The present study results can be used to improve clinical capability regarding radiation protection, provide related strategies, and solve problems.

EURAMET DOSEtrace supplementary comparison in terms of the ambient dose equivalent/rate for photon radiation (EURAMET.RI(I)-S18)

Main textA supplementary comparison in terms of the ambient dose equivalent/rate was organized within EURAMET as a part of the DOSEtrace project, between 13 national metrology institutes and designated institutes. Calibration coefficients were compared for a secondary standard ionisation chamber for 3 X-ray and 2 γ-ray radiation qualities used in the field of radiation protection. Radiation qualities were established according to ISO 4037-1. Measurements were performed between 2019 and 2021.For the purpose of this comparison, it was considered that the reported uncertainty was confirmed if the relative deviation from the comparison reference value was smaller than or equal to the associated uncertainty. All the reported results by all the partners satisfied this criterium. Three participants were not able to perform calibrations in all mandatory radiation qualities, due to technical problems. The results are published in the Key Comparison Data Base (KCDB) of the BIPM as supplementary comparison EURAMET.RI(I)-S18.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Дозы облучения населения Беларуси вследствие аварии на Чернобыльской атомной электростанции на 2021-2025 гг.

In accordance with the Laws of the Republic of Belarus «On the social protection of citizens affected by the accident at the Chernobyl NPP» dated January 6, 2009 and «On the legal regime of territories exposed to radioactive contamination due to the accident at the Chernobyl NPP» dated May 26, 2012, the value of the average annual effective dose of exposure to residents is one of the indicators of the radiation situation in settlements contaminated with radionuclides as a result of the Chernobyl accident. The objective: to update the method for assessing the exposure doses to the population in the situation of existing exposure after the Chernobyl accident and, on its basis, to assess the average annual effective exposure dose to residents of settlements of the Republic of Belarus due to the Chernobyl accident for the period 2021-2025. The method for estimating the average annual effective doses due to external and internal irradiation to residents of radioactively contaminated settlements of the Republic of Belarus has been improved taking into account international recommendations in the field of radiation protection, changes in the radiation situation in the long-time period after the Chernobyl accident and the new data on individual dosimetry of internal exposure to the population based on the results of whole-body counter (WBC) measurements. An assessment of the average annual effective exposure doses to the population of the Republic of Belarus residing in the territory of radioactive contamination was carried out, and based on its results, the Catalog of average annual effective exposure doses to residents of 2193 settlements for the period 2021-2025 was compiled. According to the compiled Catalog of average annual effective exposure doses to residents of settlements located on the territory of radioactive contamination of the Republic of Belarus, in 29 settlements out of 2193, the total effective exposure dose can exceed 1 mSv/year, in addition, it is about 1 mSv/year in 5 settlements. In none of the settlements, the average annual effective radiation dose can exceed 5 mSv/year. Valid for the period 2021-2025 Catalog of average annual effective exposure doses to the residents of settlements located on the territory of radioactive contamination of the Republic of Belarus, along with data on the density of contamination of the territories of the Republic of Belarus with long-lived radionuclides, was used to compile the List of settlements and objects located in the zones of radioactive contamination, and to adopt a Resolution of the Council of Ministers of the Republic Belarus on designation of settlements to the corresponding zones of radioactive contamination.

Study on neutron–gamma discrimination method based on the KPCA-GMM-ANN

Neutron–gamma discrimination plays a fundamental role in the fields of radiation protection and nuclide identification. The pulse-shape discrimination (PSD) of liquid scintillators has been widely used as an effective neutron–gamma detection method. In this paper, the KPCA-GMM-ANN combined algorithm is studied for neutron–gamma discrimination. Two radioisotope neutron sources (252Cf and 241Am–Be) were used. The EJ309 liquid scintillator detector was used to output the neutron and gamma pulse signals. The kernel principal component analysis (KPCA) was used to reduce the dimension of the characteristic value of the pulse signal, the gaussian mixture model (GMM) was used to cluster the dimensionality reduction results, and the artificial neural network (ANN) was trained to identify the particle categories and output the clustering results. The KPCA-GMM was compared with the KPCA-GMM-ANN using F1 score(F1). The discrimination error ratio (DER) was used to compare the KPCA-GMM-ANN with others' ANN. In all datasets, the KPCA-GMM-ANN's F1 were higher than 0.97, and its DER were lower than 0.035. The results show that the KPCA-GMM-ANN has good discrimination effect, can handle high-dimensional data, and has good generalization ability.

Analysis of the Activities of the Website “Question and Answer about Radiation in Daily Life” after the Accident at the Fukushima Daiichi Nuclear Power Plant and Some Lessons Learned from It: To Pass on This Experience to the Future

After the accident at the Fukushima Daiichi Nuclear Power Plant, artificial radionuclides such as radioactive cesium and iodine were released into the environment. It caused great anxiety not only in the vicinity of the Fukushima Daiichi Nuclear Power Plant but also in other regions of the world. Some members of the Japan Health Physics Society (JHPS), a leading academic society in Japan in the field of radiation protection, volunteered to establish a website called “Question and Answer (Q&A) about radiation in daily life” shortly after the accident to help reduce the residents’ anxiety about the health effects of radiation. In August 2011, “Committee for Q&A about radiation in daily life” was established in JHPS, making the website-related activities a responsibility of JHPS. The Q&A website continued to respond to the questions from the general public with expertise and sincerity until February 2013 when the Committee members decided to end the activities because the number of questions received had gradually decreased with the passage of time. This paper aims to introduce the following: the activities of the Q&A website during the two years (2011–2013), the stance chosen for the activities, the information related to the website activities and the analysis of Twitter data. Building on the experience and the knowledge obtained from the activities, it also discusses issues and experiences that can be utilized in the initial response to emergencies for radiation protection experts as well as those in other fields.

The reconstruction of 3D radiation field based on sparse measurement data

With the development of nuclear technology, an increasing number of occupational workers are exposed to radioactive environments. The three-dimensional(3D) dose rate field is of great significance in the radiation protection field. Many researchers focus on the reconstruction of 2D radiation fields but few of them paid attention to the reconstruction of the 3D dose rate field based on sparse measurement data. In this work, the net function interpolation method is introduced to reconstruct 3D radiation field using sparse sampling nodes. In contrast to traditional dose rate interpolation methods, we interpolated the value of the inverse of the dose rate. By using the inverse, the field to be interpolated follows a power function, which fits the net function much better than the direct interpolation. The proposed method includes interpolation on sampling grid lines, interpolation on sampling grid plane and interpolation in the three-dimensional space. Additionally, four simulation experiments are carried out to prove the effectiveness and accuracy of the proposed method. The first two cases are radiation fields formed by a single radioactive source without and with shielding. Radioactive environments caused by multiple radioactive sources without and with shielding are conducted in Case 3 and Case 4. The reconstruction radiation field is compared to the radiation field simulated by the Monte Carlo method. The average relative errors of the four cases are 0.82%, 2.13%, 1.71% and 4.27% respectively using approximately 1% measurement data. The experimental data provided by other researchers are also used to validate the effectiveness of the proposed method and the minimum relative error of Case 5 is 4.67%. Therefore, the net function is an interpolation method suitable for the radiation field and it can reconstruct the 3D radiation field accurately with sparse data.

Radiation attenuation properties of novel glass system using experimental and Geant4 simulation

The purpose of this study is to estimate the radiation shielding capacities of glass systems with the system of 45 SiO2 – 15 CaO – (40-x) BaO – (x) ZnO (where x = 0,10,20, 30, and 40 wt%). The mass attenuation coefficients, μ/ρ of these glasses have been calculated by using XCOM software and Geant4 simulation toolkit tool in the energy range of 0.0595 MeV–1.410 MeV. The experimental data have been carried out using a narrow beam using the NaI(Tl) scintillation detector at the energies of (59.52 KeV) 241Am, (661.66 keV) 137Cs, (1173.23, 1332.50 keV) 60Co, 152Eu(121.78, 244.69, 344.28, 964.13, 1408.1 KeV). The MAC calculated results were compared with the experimental values. There have been good agreements noticed. The other attenuation parameters were calculated such as the linear attenuation coefficient (μ), half value layer (HVL), mean free path (MFP) and the effective atomic number (Zeff). The attenuation results of this glass system were compared with some recently published commercial glasses, and the results showed that this glass system is important in the radiation protection field.

Radiation risk perception among parents and legal representatives of children undergoing radiological examinations

Risk communication is one of the stages of health risk analysis and is an interactive process of exchange of information and opinions about risks, including medical risks, between risk assessment specialists, decision makers, the media, stakeholder groups and the public. In organizing interaction with stakeholders in the risk communication process, sociological research helps to explore the attitudes of the actors. One of risk communication situations in the field of radiation protection is information provision to patients and their legal representatives about radiation health risks due to the medical radiology examinations. The aim of this study was to assess the radiation risk perception among parents and legal representatives of children undergoing radiological examinations. Parents and legal representatives of children undergoing hospital treatment from November 2021 to March 2022 were interviewed in a large pediatric infectious diseases hospital. A questionnaire designed at St. Petersburg Research Institute of Radiation Hygiene was used for the interviews. In total, 125 people were interviewed. The study showed that there were no significant differences in the perception of radiation risks among parents and legal representatives of children undergoing inpatient treatment with different socio-demographic characteristics. The level of knowledge was not identified as a factor shaping a tolerant attitude toward medical radiation risks. Parents and legal representatives of children undergoing hospital treatment show high rates of trust in the attending physicians and medicine in general. The study results show that those who have been informed about the risks generally have lower risk perception for radiological medical examinations than those who have not been informed about the risks.

Microwave assisted synthesis, photoluminescence and X-ray/gamma ray absoprtion properties of red CaZrO3:Eu3+ perovskite

Nanocrystalline orthorhombic CaZrO3:Eu3+ (1–4 ​mol%) perovskite was synthesized by microwave assisted combustion method. To know the phase purity, functional group, surface morphology, structural analysis and energy band gap, the synthesized sample was characterized by using various techniques. The powder X-ray diffraction analysis clearly confirms the formation of pure orthorhombic phase of CaZrO3:Eu3+ (1–4 ​mol%) nanoparticles. The surface morphology shows the formation of voids and pores which is the characteristic of combustion method. The d-spacings, selected area electron diffraction pattern and the crystallite size obtained from transmission electron microscopic analysis matches well with that of X-ray diffraction pattern.The optical energy band gap determined from Wood and Tauc's relation decreases with decrease in crystallite size and with increase in dopant concentration. The photoluminescence emission excited at 306 ​nm wavelength shows the characteristic peaks of Eu3+ ions. CIE and CCT coordinates clearly shows that CaZrO3:Eu3+ (1–4 ​mol%) nanophosphor is one of the promising candidate for display applications. Further, the interaction of X-ray/gamma radiation with CaZrO3:Eu3+ is also studied. We have reported the X-ray/gamma radiation interaction parameters such as mass attenuation coefficient and other parameters at different energies. The established data may be useful in the fields of radiation protection. Calcium and Zirconium being heavier elements, there is an expectation that, the CZ perovskite might be a good X-ray/gamma ray absorber and hence X-ray/gamma ray interaction parameters are discussed.