Sources Of Ionizing Radiation Research Articles

Alpha Industrial Services Limited: Managing Safety Affordably

Industrial radiography (IR) is an important application of radiation in which an ionizing radiation source is used to detect any cracks or hidden flaws within machinery and welding joints. A category-2 radioactive source (if not shielded properly, it can cause serious and potentially terminal health consequences) is used in IR. It can cause severe detrimental effects like burns if not used properly. There have been many IR related accidents worldwide which are also available on the International Atomic Energy Agency (IAEA) website. This case is written on two isolated events that happened in Pakistan within the same company (name changed) engaged in IR services within Pakistan. Alpha Industrial Services Limited’s (AISL) higher management was dealing with a prevailing financial crunch, and the company was struggling to maintain its quality of services and safety at an affordable cost. The leadership of the company made several decisions to manage the financial crisis.

Thermally Controllable Decolorization of Reusable Radiochromic Complex of Polyvinyl Alcohol, Iodine and Silica Nanoparticles (PAISiN) Irradiated with γ-rays

Some medical and industry workers using ionizing radiation sources have potential risks of accidental high-dose exposure of their extremities, particularly their hands. While practical dosimeters suitable for on-site real-time monitoring of hand exposure are not yet available, they are desirable to be developed. Thus, the authors focused on the application of a reusable radiochromic complex composed of polyvinyl alcohol, iodide and silica nanoparticles, named “PAISiN”, and examined their dose responses and thermal stabilities of radiochromic reactions. Three PAISiN samples each were irradiated with 5, 10 and 20 Gy of 137Cs γ-rays, and time changes of the radiation-induced colors were observed at different temperatures: 20 °C (in a laboratory), 40 °C (in an oven) and 5.5 °C (in a refrigerator). It was confirmed that the PAISiN samples presented a red color that was easily detectable by the naked eyesight immediately after irradiation. The coloration was cleared within 24 h for 5 Gy irradiation at room temperature. The decolorization process was remarkably accelerated at 40 °C; it was erased in just 2 h. In contrast, storing in the refrigerator (5.5 °C) kept the color persistently for at least 4 days. These findings indicate that we could flexibly control the decolorization process of PAISiN in accordance with the objective of radiation monitoring.

Local Diagnostic Reference Levels (LDRLs) for routine X-ray examinations in Morocco

In Morocco, the radiation protection of patients undergoing medical imaging examinations using ionizing radiation sources is now governed by specific provisions of Chapter VII of Law no142-12 (Loi no142-12 – AMSSNuR, 2015). The principle of justification of procedures and the principle of optimization of doses delivered constitute the basis of the legislation governing medical exposure. DRLs are considered as an important optimization tool encouraging healthcare professionals to optimize their practice and assure a better patient safety. In this survey, Local Diagnostic Reference Levels (LDRLs) were established for the eight most frequent examinations in Morocco. Data from 1747 patients were collected from seven regional hospitals. The proposed LDRLs were defined as the 75th percentile of the mean entrance surface dose distribution (ESD) in mGy using the indirect dosimetry method according to the IAEA Report Series No. 457. The LDRLs values reported in this study were for the eight examinations: skull (PA) 2.8 mGy, chest (PA) 0.51 mGy, abdomen (AP) 7.6 mGy, pelvis (AP) 6.45 mGy, lumbar (AP) 7.8 mGy, lumbar (Lat) 10.7 mGy, cervical (AP) 2.2 mGy, and cervical (Lat) 2.4 mGy. The DRLs reported in Morocco were compared with those of international authorities and other countries: IRSN (France), NRPB (UK), Japan, Sudan, and Iran. The present work assesses the local DRLs in Morocco and constitutes a starting point that will provide professionals with a tool to help them optimize the doses delivered to patients. Furthermore, the definition of national DRLs by radiography is an essential step in the process of optimizing medical exposures.

Monte Carlo Code Calculation for the Characterization of 10nm Nano-Layers Coated 50nm 90Y Radionuclide Nanospheres Radiation in the Liver Radionuclide Therapy

Purpose: Cancer radionuclide therapy is an effective, beneficial, and crucial method of cancer treatment that uses unsealed radioactivated radionuclides sources that are attached to a targeting vector to deliver therapeutic radiation doses from the ionizing radiation source to specific disease sites either for curative intent or for disease control and palliation for the patient pain decreasing. For this aim, Monte Carlo N–Particle 5 (MCNP5) MC computational code was employed for simulations and calculations as well as radiation transport.
 Materials and Methods: 50nm 90Y radionuclide nanosphere was modelled coated by a 10nm coating layer with some non-toxic high and low Z materials. Physical interactions, such as β-ray and the simulated coating materials were studied and radiological parameters were scored by the used MC code. Attenuation of β-ray, and production of the bremsstrahlung X-ray photons and other phenomena were simulated by the code and analyzed. MC code estimated the effect of the simulated coating materials, such as Gold, Platinum, Gaddolonium, Silver, and Epoxy-Resin on the radiation characteristics around the modelled nano-radionuclide per 2nm from the radiation source surface to 1µm distance. Produced bremsstrahlung X-ray by the source coating material and tissue atoms, emitted β-particle number, flux over the surfaces (per 2nm), radiation fluence of photon and β- ray, deposited energy per gr of the cell medium, and average dose to the cells around the 500nm and 1µm distance from the radionuclide source surface also was derived.
 Results: Our results showed that coating the radionuclide with the materials especially high Z (Gold and Platinum) materials may produce a dual emitter radiation source, X-ray photon and β- ray and is capable of killing the cancer cells more than the source with not-coated source.
 Conclusion: Our conclusion was that coating the β- ray emitter radionuclides, especially high-energy β- ray, enhances its therapeutical capability with X-ray and β- ray emission. The studied coated sources in our study were performed as a dual radiation source; produced X-ray and β-ray, which increases the therapeutic efficiency of the source.

РАДИАЦИОННО-ГИГИЕНИЧЕСКИЕ ИССЛЕДОВАНИЯ ЭКСПЕРИМЕНТАЛЬНОГО ПРОИЗВОДСТВА СМЕШАННОГО НИТРИДНОГО УРАН-ПЛУТОНИЕВОГО ТОПЛИВА НА АО «СХК». Часть 2: Дозы и риски

Purpose: Assessment of the compliance of the radiation protection of workers at the complex experimental installations of JSC SChC with the requirements of the Russian radiation safety standards NRB-99/2009 to limit the generalized risk of potential exposure and the IAEA recommendations for not exceeding the control level of the minimum significant radiation risk. Materials and methods: The results of radiation-hygienic investigations of radiation exposure factors affecting workers involved in the manufacture of mixed uranium-plutonium nitride (MUPN) fuel at the complex experimental installations of JSC SChC are used as the input data for the preliminary assessment of radiation doses to workers. The models for assessment of radiation risk of potential exposure have been developed in accordance with the recommendations of the ICRP and the IAEA. Results: Preliminary estimates of the doses of external gamma-neutron (2.5 ± 0.5 mSv / year) and internal exposure of workers (~1 mSv/year1) are related to the current levels of exposure of workers of complex experimental installations. These levels are the result of exposure to ionizing radiation sources associated both with the development of new technologies and with residual radioactive contamination resulting from previous activities not related to the manufacture of MUPN fuel. The presented dose estimates are related to the use of raw materials that have undergone deep preliminary purification from radiogenic impurities. When irradiated nuclear materials are used as raw materials, the levels of gamma-neutron exposure to workers will be significantly higher. The maximum increase in the generalized risk of potential exposure due to annual exposure is estimated for women aged 18 years at the beginning of exposure, for which the increase in this risk is 1.45 × 10-4 year-1, which is 1.37 times lower than the limit established by the Russian radiation safety standards NRB-99/2009: 2 × 10-4 year-1. All predicted values of the lifetime attributable fraction of radiation (LARF) in mortality from malignant neoplasms are significantly less than the control level of the minimum significant risk recommended by the IAEA (LARF = 5 %), and the maximum value of LARF = 2.8 % is achieved for women aged 18 years at the beginning of exposure. Conclusion: Restrictions on the radiation risks of potential exposure, established by NRB-99/2009, as well as those recommended by the IAEA for not exceeding the reference level of the minimum significant risk, are met with a large reserve. The results obtained and the developed methods will be used to ensure the radiation safety of workers during the transition from experimental installations to pilot industrial implementation of the technology for the production of MUPN fuel.

Selection of gamma-ray source for operational quality control of mineral raw materials

For operational and quality control of ferrous metal ores, ionizing radiation sources are used, which main characteristics are energy, activity and half-life. The technological parameters of the sources Americium-241, Thulium-170 and Cadmium-109 have been compered, and Americium-241 with an energy of 60 keV and a half-life of 458 years has been selected. Laboratory studies of the dependence of the integrated flux of scattered gamma rays on the content of total iron in the ore have been carried out. Based on the results of laboratory studies, the sensitivity and measurement cycle time have been determined for three gamma-ray sources. For all three indicators, Americium-241 has been selected for operational and quality control of ferrous metal ores. Obtained data have been used for the development and implementation of a microprocessor-based system for operational control of the total iron content in ore on a conveyor belt.

Effects of Ionizing Radiation Sources and Dose Levels on Quality Characteristics of Meal Ready to Eat

Effects of Ionizing Radiation Sources and Dose Levels on Quality Characteristics of Meal Ready to Eat

Regulatory Requirements of Quality Assurance Program in Nuclear Medicine – Review of the Procedures

The quality assurance program ensures that the entire radiological system and associated equipment are functioning properly and optimally. To this end, it is essential that a quality assurance program be in place in each medical facility where ionizing radiation sources are used, to verify the proper functioning of these instruments as well as the radionuclides measured in nuclear medicine. In addition, the procedures of the quality assurance program must comply with regulatory requirements and international recommendations. The method of this study is to review the regulatory requirements adopted by different countries regarding the quality assurance program procedures as well as various recent scientific works and those published by the International Atomic Energy Agency. In addition, to compare the radiation protection requirements of the procedures of the mentioned works; exposure justification and optimization, quality control, registration system, professional training and audit system and to suggest improvements. The result of the review study, add a procedure to the quality assurance program, so that the quality assurance attempts to cover all procedures involving sources of ionizing radiation, thus ensuring compliance with the standards of radiological safety in nuclear medicine facilities.

Design and implementation of a low cost, high performance ionizing radiation source detection and source direction finding system

Design and implementation of a low cost, high performance ionizing radiation source detection and source direction finding system

FORMATION OF REQUIREMENTS FOR THE METHOD OF EXTENDING THE TERM OF SERVICE OF CLOSED SOURCES OF IONIZING RADIATION

Today, sources of ionizing α-, β- and γ-radiation are used in various spheres of the Ukrainian economy. Their service life is set by the manufacturer from the moment of their manufacture and determines the duration of use of the source of ionizing radiation.
 According to the current legislation of Ukraine, spent sources of ionizing radiation, which have expired, are subject to transfer to specialized enterprises for radioactive waste management and disposal. If the fact of preservation of radiation characteristics, tightness and absence of defects and their signs on the closed source of ionizing radiation is confirmed, its service life can be extended. But the legislation does not regulate the conditions for extending the service life, and as a consequence of the duration of their operation.
 The purpose of this article is to form requirements for the method of extending the service life of closed sources of ionizing radiation. To do this, the authors of the article solved the following tasks: a review of sources of ionizing radiation and their use in industry; the general classification of ionizing radiation on various classification signs is formed; the analysis of works influencing establishment of term of use of sources of ionizing radiation is carried out; the general requirements and algorithm of a technique of prolongation of service life of sources of ionizing radiation are developed.
 Establishment of service life by the manufacturer from the moment of manufacture of a source of ionizing radiation occurs under condition of its conformity to the purpose and the basic technical requirements of standards and requirements to tightness of its design which under proper operating conditions should provide radiation safety in places of operation and storage.
 Conformity assessment of ionizing radiation sources is carried out in accordance with the requirements of the "Technical Regulations for Closed Ionizing Radiation Sources".
 Metrological verification of ionizing radiation sources is performed in accordance with the requirements of the approved "Method of calibration of ionizing radiation sources" by determining such metrological characteristics as the activity of the ionizing radiation source, particle flux at an angle of 2π and specific or volumetric activity.
 The authors formulate the requirements and propose an algorithm of the method of extending the service life of ionizing radiation sources based on the processing of the results of their calibration using control charts. Using the method of control cards allows not only to decide on the continuation of operation and service life of the source of ionizing radiation, but also to determine the duration of the extended service life of the source

Analysis of patient medical exposure in X-ray diagnostics in Russia for half a century (1970–2019)

During last 50 years, firstly in the RSFSR in the USSR (1970-80), then in the Russian Federation - RF (1990-2019), the authors studied the radiation safety issues of patients from medical exposure. The reader is offered a complex radiation-hygienic analysis of the 50-year medical exposure of patients and of the population in Russia to inform and analyze the available data on the most common type of use of ionizing radiation sources in the national economy. For a half century, several generations of people have changed and medical diagnostic X-ray equipment and technologies have also radically changed. The information from this article was obtained on the basis of radiation-hygienic statistics, as well as considered our research. The data is presented at the federal level in the form of the volume of research carried out- determined by the number of X-ray procedures, as well as the level of medical exposure in the form of effective dose of patients in Russia - a huge region with a population of about 150 million people, where about 200 million X-Ray procedures were performed annually, i.e. about 10 billion X-Ray procedures for the entire observation period. During the study, a collective effective dose was - 6.5 million person-Sv at the rate of 100 thousand person-Sv and more per year. The paper presents the dynamics and the structure of the studied indicators depending on the type of medical exposure, as well as its localization. The contribution of the X-ray diagnostics to the total volume of radiation diagnostics, which is developing dynamically, is presented. It was found that throughout the study, there were two oppositely directed processes: an increase in the number of X-Ray procedures and a decrease in the effective doses of patients. At present, the minimum dose has been reached, after that it has been increasing began, associated with the use of new computer technologies. It was determined that, depending on the localization, the main radiation load during X-ray procedures falls on the skeleton and digestive organs. It is shown that during the study period (in 1986) there was an accident at the Chernobyl, which significantly affected on medical activities and, in particular, X-ray diagnostic indicators. The paper shows the consequences of these situations. In general, the data presented is huge in volume and significant in information content. The information obtained on the basis of such a unique data is representative and allows, firstly, to analytically study the issues of radiation protection of patients and, secondly, to plan the strategy and tactics of its development.

Characterization and implementation of a miniature X-ray system for live cell microscopy

The study of radiation effects on biological tissues is a diverse field of research with direct applications to improve human health, in particular in the contexts of radiation therapy and space exploration. Understanding the DNA damage response following radiation exposure, which is a key determinant for mutagenesis, requires reproducible methods for delivering known doses of ionizing radiation (IR) in a controlled environment. Multiple IR sources, including research X-ray and gamma-ray irradiators are routinely used in basic and translational research with cell and animal models. These systems are however not ideal when a high temporal resolution is needed, for example to study early DNA damage responses with live cell microscopy. Here, we characterize the dose rate and beam properties of a commercial, miniature, affordable, and versatile X-ray source (Mini-X). We describe how to use Mini-X on the stage of a fluorescence microscope to deliver high IR dose rates (up to 29 Gy/min) or lower dose rates (≤ 0.1 Gy/min) in live cell imaging experiments. This article provides a blueprint for radiation biology applications with high temporal resolution, with a step-by-step guide to implement a miniature X-ray system on an imaging platform, and the information needed to characterize the system.

Manufacturing of an Iridium-192 Ionizing Radiation Source for Nondestructive Testing

Manufacturing of an Iridium-192 Ionizing Radiation Source for Nondestructive Testing

Comparative analysis of population mortality in the cities of Severodvinsk and Arkhangelsk

Increasing use of ionizing radiation sources in different spheres of human life dictates the need for investigating the effects of low-dose radiation on mortality and morbidity. The aim of this study was to compare mortality from the most common non-communicable diseases in the cities of Severodvinsk and Arkhangelsk. We analyzed the rates of age- and sex-specific mortality from circulatory system diseases (CSD), malignancies, digestive system disorders, respiratory system diseases, and external causes. CSD-related mortality among men and women past working age was higher in Severodvinsk than in Arkhangelsk (median (Q1; Q3): 3,349 (3,271; 3,458) vs 2,651 (2,618; 2,756), p < 0.012; 1,947 (1,890; 2,022) vs 1,753 (1,727; 1,809), p < 0.012; 292 (281; 342) vs 265 (253; 274), p < 0.025, respectively). For other causes of death, mortality rates in Severodvinsk did not exceed those in Arkhangelsk. Increased mortality from CSD in Severodvinsk cannot be linked to socioeconomic conditions or chemical air pollution because the standard of living is higher in Severodvinsk than in Arkhangelsk, whereas the level of chemical pollution is lower. At the same time, the presence of the nuclear shipyard and radioactive waste repository in Severodvinsk could cause chronic exposure to low-dose radiation. It is important to expand preventive measures aimed at early detection of vascular damage in nuclear workers and general groups of population residing in the vicinity of hazardous radiation sites.

Investigation of the effectiveness of antimicrobial treatment of poultry products by electrophysical methods

Improved methods of processing food and agricultural products make it possible to achieve an optimal effect at an acceptable level of its quality. In radiobiology, Methods of synergistic effect of two factors are widespread, in particular, the combination of treatment with ionizing radiation (IR), UV and plasma. The use of these methods in the production cycle can significantly improve processing efficiency. In the present work were treated combined feeds of ‘PK-5’ and ‘PK-6’ in order to investigate the synergistic effect of IR treatment and high pressure gas discharge plasma (HP GDP) radiation. As the source of IR was used the nanosecond electron beam (NEB) of the accelerator URT-1 (1 Mev). To create the HP GDP was used a high-voltage nanosecond generator GVI-150 (150 kV). The obtained results indicate the presence of a synergistic effect of the combined effects of plasma radiation and NEB.

Public safety conditions under radiological emergencies monitoring comprehensive system mobile facilities application

The article presents examples of radiological emergencies with ionizing radiation sources used in radioisotope devices. A number of measures aimed at emergency response in relation to such emergencies, including in relation to the control of the radiation situation (CRS) and its assessment, are considered. A variant of building a complex of mobile CRS tools for a comprehensive monitoring system for the state of the population protection is presented. Special attention is paid to the justification and optimization of the CRS use in situations of control loss over IRS, including technical, organizational and scientific approaches to the use of these mobile tools. In order to optimize the group integrated use of mobile CRS tools, typical radiological situations are studied in advance and rational options for the mobile CRS tools using are selected, taking into account different environmental conditions, including natural-geographical, climatic and man-made factors. The considered approaches to optimization in the use of mobile means of comprehensive systems of the public protection conditions monitoring in radiological emergencies allow, first of all, to increase the efficiency of their use and ensure the successful implementation of tasks for the prevention and elimination of such emergencies consequences.

Outlook for nuclear physics research in Belarus

The future nuclear physics research capabilities for scientists from Belarus are discussed. The following branches for the activity: megascience class research platforms created in Russia and the European Union, a new generation of ionizing radiation sources, use of the world nuclear science network for short-term research and, monitoring of nuclear power plants are debated. The purposes of nuclear physics research are suggested to be a balanced combining of the further penetration deep into the matter, to clarify its status and time evolution and, the routine activity associated with clarifying the details of the world, for which sufficiently well-developed models have already been created. Further, the goals of nuclear physics research are specified. They include preventing the loss of knowledge in the field of nuclear physics; conservation of the acceptable qualification and its reproducibility, maintaining the appropriate level of the engineering corps for the perception of the latest knowledge. This article is based on the author’s personal experience in participating in projects of high scientific significance. The route of considering the areas of application of nuclear physics scientists’ efforts is formed according to the principle of maximum return from the highly qualified personnel (PhDs and doctors of science). Ain importance of training undergraduates and graduate students for a scientific career is underlined. Finally, a need to maintain a high level of knowledge in the branch for the expertise upon the request of the government to secure and develop the country is pointed out.

Conversion of Radiophotoluminescence Irradiation into Electricity in Photovoltaic Cells. A Review of Theoretical Considerations and Practical Solutions

This review presents the current state of the knowledge regarding the use of radioactive sources to generate photonic light in scintillators as converters of ionizing radiation to electricity in photovoltaic cells. The possibility of using the phenomenon of the excitation of light photons in the scintillation materials during the interaction with particles and photons of ionizing radiation was analyzed in detail. The light photons obtained in such a way can generate an electric charge in photovoltaic cells. The whole process can be named as a nuclear cell (nuclear battery). Theoretically, the use of such physical phenomena seems to be an ideal practical solution to meet the energy needs of the modern world. However, there are many physical and technical problems that limit its widespread use in practical applications. In an ideal system, the ionizing radiation sources can emit the radiation for billions of years, and the energy of particles and photons from the radiation can be converted into photons in the scintillation material, with energy suitable to generate a photoelectric effect in a photovoltaic cell. Such a cascade sequence of different physical phenomena allows, from a theoretical point of view, for the creation of a virtually inexhaustible source of electricity. This review of historical and current literature reports aims to bring closer the idea of “energy perpetuum mobile”, which has troubled many scientists around the world for centuries.

Active Versus Passive Flow Control in UVC FILTERs for COVID-19 Containment.

Ultraviolet radiation as a germicide is widely used in the health field and even in domestic hygiene. Here, we propose an improvement in low-cost portable units of filtration for indoor air, which is based on ultraviolet radiation. In the current technology, to carry out an air filtration with a suspension of aerosols in which there is a likely concentration of pathogens, whether viral, bacterial or molds, the air is forced to pass as close as possible to the ionizing radiation source (near field). Since the optical mass is very small, the desired effect can be achieved in a considerably short time, deactivating the infective potential of these biological agents. The proposal of this work is the regulation of the flow or speed control of passage through these filters by passive elements instead of by electronic control systems. For this, two devices have been designed, simulated, and built, obtaining similar net pathogen inactivation rates under different flow rates. The passive flow control device has demonstrated higher performance in terms of flow rate and lower cost of production since they do not require electronics and are produced with fewer diodes. This passive device has also shown a lower projection of maintenance cost, lower energy consumption rate (higher efficiency), and longer projection of useful life.

Selection of elements of the detector unit of the system for measuring the coordinates of gamma radiation sources

The article considers the current problem of creating modern, effective and reliable systems for monitoring the radiation situation and the operational search for nuclear radioactive materials and radiation sources that have come out of regulated supervision. A promising method of non-destructive testing using semiconductor detectors of ionizing radiation is used for radiation-environmental monitoring, prevention of the consequences of nuclear smuggling and determination of coordinates of ionizing radiation sources. The method for determining the direction to pulsed and constant sources of gamma radiation uses the ratio of the number of signals coming from the detectors located in the absorbers of a special geometric shape. The purpose of the article is to select the elements of the detector unit for the tool, which uses the method of absorption to determine the coordinates of the source of gamma radiation. The main attention is paid to the search for optimal characteristics of the material of the radiation absorber and the choice of the detector. The article analyzes the parameters of nuclear radiation detectors from different semiconductor materials, highlights and describes their characteristics. Analysis of experimental data and theoretical calculations allows us to assert that in the case of coordinateometry of gamma-radiation sources, a wide-gap semiconductor CdZnTe should be chosen as a detector material. For detectors of this type, the energy range is from 20 to 3000 keV, the operating temperature range is from -40 to +50 0С, and the energy resolution is of the order of several percent.