Conducting Studies of the Am-241 Radionuclide Incorporated into the Human Body Using a Wound Detector

Purpose: to develop a method for experimental study of the distribution of radionuclide 241Am in human organs and tissues during wound admission to clarify the process of formation of doses of alpha radiation. Material and methods: in clinical practice of Burnazyan FMBC of the FMBA of Russia To improve the method of determination, an experiment was performed to determine the depth of radionuclide on pigskin with the location of 241Am point sources behind different thicknesses. Results: the used methods of measurement, tested on pigskin, allowed to obtain the dependence of the localization depth of radionuclide 241Am on the measured on the surface of the tissue ratios of photons with different energies. Conclusion: Set the ratio of photons with different energies on the thickness of the barrier (depth), and proven methodology allow you to go directly to the planning of experimental studies on the barrier effect created in the bone material, and including a radionuclide, the formation of doses of alpha radiation on the bone marrow.

Study of CMOS Sensing System for Radon and Alpha Radiation

This study focuses on a CMOS sensing system for Radon and alpha radiation, which is based on a semiconductor device that is integrated monolithically on a single chip with the Readout Circuitry, thus allowing fabrication of a low-power and low-cost sensing system. The new sensor is based on a new mosaic design of an array of Floating Gate non-volatile memory-like transistors, which are implemented in a standard CMOS technology, with a single polysilicon layer. The transistors are electrically combined in parallel and are operated at subthreshold, thus achieving very high sensitivity and reduced noise. The sensing system’s architecture and design is presented, along with key operation concepts, characterization, and analysis results. Alpha and radon exposure results are compared to commercial radon detectors. The new sensor, dubbed TODOS-Radon sensor, measures continuously, is battery operated and insensitive to humidity.

Alpha dose rate and decay dose impacts on the long-term alteration of HLW nuclear glasses

In the prospect of deep geological disposal, the long-term behavior of high-level nuclear glasses has to be investigated regarding alpha radiation induced by long-life minor actinides. The present study focuses on the effects of alpha radiation on the long-term chemical reactivity of R7T7-type glasses, by separately considering the alpha dose rate and the alpha decay dose. Old SON68 glasses doped with 238/239PuO2 or 244CmO2 were studied to simulate high alpha dose rates corresponding to an early water ingress and a high level of alpha decay doses corresponding to long-term disposal conditions. A part of the 238/239Pu-doped glass block was annealed to fully recover the irradiation-induced damage accumulated since the glass was fabricated and to dissociate the effect of the alpha dose rate from that of the alpha decay dose. The glasses were then leached under static conditions at 90 °C for several years. The results showed that the residual alteration rate is not affected by the alpha dose rate over a wide range of dose rate values expected under disposal conditions: this glass remained relatively insensitive to the alpha radiolysis phenomena at the glass–water interface. However, over the duration of the experiments, the residual alteration rate of the damaged 238/239Pu-doped glass was enhanced compared to that of the annealed glass. This result is in agreement with those obtained on the 244Cm-doped glass and with reported values in the literature on simplified externally irradiated glasses, indicating that the ballistic effects of the recoil nuclei are responsible for this increase in the residual alteration rate.

Особенности скорости выхода радона из грунта в приземную атмосферу

The paper presents the results of the analysis of long-term series of monitoring data on the radon flux density. They were produced using a accumulation chamber of our own design, which allows, in terms of the readings of alpha radiation counters, to obtain the values of the radon flux density. The main results and the most illustrative examples of the behavior of the investigated characteristic of radon are present in the work. As a result, conclusions were drawn about the features of radon release rate from the soil into the surface atmosphere at different time scales and under different meteorological conditions, which can be used in the future to monitor the radon flux density using ionizing radiation detectors, and is also fundamental for the development new models. В работе представлены результаты анализа многолетних рядов данных мониторинга плотности потока радона. Они производились с помощью накопительной камеры собственной разработки позволяющей в пересчете с показаний счетчиков альфа излучения получить значения плотности потока радона. В работе освещены основные результаты и наиболее показательные примеры поведения исследованной характеристики радона. В результате были сделаны выводы об особенностях скорости выхода радона из грунта в приземную атмосферу на различных масштабах времени и при различных метеорологических условиях, что может быть использовано в дальнейшем с целью мониторинга плотности потока радона при помощи детекторов ионизирующего излучения, а также несет фундаметальный характер для разработки новых моделей.

Determination Radon Concentration (Radon Gas) in Urine of Patients with Cancer

The present study aims at studying the measurement radon concentration (Radon gas) in the urine of patients with cancer, that made up of (23) different samples of patients’ urine. These samples have collected from Kirkuk Oncology & Hematology Center. Chemical etching process for CR-39 track detector has used to record the traces of Alpha particles “alpha rays” or “alpha radiation” that comes from Radon included in the models. The Plastic Tubing – Tubes that contain some models in reagent irradiation process, which shaped as U letter, have been used. The results illustrated that the highest concentration of Radon is (8.9) Bq.m-1 in R14 model, as well as the lowest concentration of Radon is (1.5) Bq.m-1 in R4 model. The Radon levels that have been measured are within the natural limits of radioactive decay caused by radioactive nuclide or “radioactive isotope” in urine of patients with cancer; these are not a risk in humanity.

Comparative Studies of Ionizing Radiation Detectors Made on the Basis of Various Types of Diamond Plates

The results of experiments on the study of polarization phenomena and the charge collection efficiency in test structures of diamond ionizing radiation detectors using diamond plates of various types, including single-crystal NRNT-type, single-crystal CVD-type, as well as polycrystalline type, when exposed to alpha-radiation with an energy of 5.5 MeV are presented. Studies have demonstrated the existence of a number of problems with the device quality of diamond plates that affect the performance of spec-trometric-type detectors.

Lyman-alpha radiation pressure: an analytical exploration

ABSTRACT We study radiation pressure due to Ly α line photons, obtaining and exploring analytical expressions for the force-multiplier, MF(NH, Z) = Fα/(Lα/c), as a function of gas column density, NH, and metallicity, Z, for both dust-free and dusty media, employing a WKB approach for the latter case. Solutions for frequency offset emission to emulate non-static media moving with a bulk velocity v have also been obtained. We find that, in static media, Ly α pressure dominates over both photoionization and dust-mediated UV radiation pressure in a very wide parameter range (16 < log NH < 23; −4 < log [Z/Z⊙] < 0). For example, it overwhelms the other two forces by $\lower.5ex\hbox{$\,\, \buildrel\gt \over \sim \,\,$}10$ (300) times in standard (low-Z) star-forming clouds. Thus, in agreement with previous studies, we conclude that Ly α pressure plays a dominant role in the initial acceleration of the gas around luminous sources, and must be implemented in galaxy formation, evolution and outflow models and simulations.