Investigation of gamma background in parks and recreation areas of the city of Petropavlovsk-Kamchatsky

Работа посвящена исследованию гамма-фона в городской среде Петропавловска-Камчатского (Камчатский край), а именно в парках и зонах отдыха. Измерения мощности поглощенной дозы проводились на разработанном коллективном Томского политехнического университета (ТПУ) дозиметре с использованием органического сцинтиллятора ВС-408, который является схожим по техническим характеристикам с БДКГ-01. С целью вычисления поправочного коэффициента для перевода показаний дозиметра из имп/с в нЗв/ч был проведен ряд калибровочных измерений с точечными источниками гамма-излучения – 60Co и 137Cs. Разработанным дозиметром проводились измерения длительностью не менее 5 минут в различных районах города Петропавловска-Камчатского, особое внимание уделялось исследованию объектов техносферы из материалов, являющимися природными источниками повышенного гамма-излучения. Исследования показали, что памятник В. И. Ленину и стела «Город воинской славы» в центре города Петропавловска-Камчатского содержат граниты у их основания, которые дают завышенный гамма-фон The work is devoted to the study of the gamma background in the urban environment of Petropavlovsk-Kamchatsky (Kamchatka Territory), namely in parks and recreation areas. Measurements of the absorbed dose rate were carried out on a scintillation organic dosimeter developed by the team of the Tomsk Polytechnic University (TPU), which is a more budgetary analogue of the BDKG-01. In order to calculate the correction factor for converting the dosimeter readings from impulses/s to nSv/h, a number of calibration measurements were carried out with point sources of gamma radiation – 60Co and 137 Cs. The developed dosimeter carried out measurements with a duration of at least 5 minutes in various districts of the city of Petropavlovsk-Kamchatsky, special attention was paid to the study of technosphere objects made of materials that are natural sources of increased gamma radiation. Studies have shown that the monument to V. I. Lenin and the stele « City of Military Glory » in the center of the city of Petropavlovsk-Kamchatsky contain granites at their base, which give an overestimated gamma background.

Влияние зданий на суммарный гамма-фон

The influence of buildings on the total gamma background radiation was investigated. The total gamma radiation between a building made from bricks and a field, which are 100 m apart (away from the influence of other buildings), was measured using a scintillation detector. Measurements of ambient equivalent dose rate at different heights above the soil and a horizontal distance from 0.1 m – 100 m in variable steps were taken. A new approach was developed to assess the contribution of gamma background radiation from the soil and the building to the total gamma background radiation. It was obtained that the gamma background radiation contributed by buildings, greatly affects the total gamma background radiation up to a distance of 2 m, at which there was a significant decrease in the total gamma background radiation. The percentage of the building that contributes to the total gamma background radiation is noted to be between 4 – 29% of the total gamma background. This shows that most of the background radiation in the environment is contributed by the gamma background radiation in the soil. Also, the annual equivalent dose received by a person who sits near the building was 0.09 mSv, which was higher than an adult who works far away from the building (0.08 mSv). Both were however less than the global level. It also was found that the best place to install a detector for measuring gamma radiation was found to be a distance of 1.5 m away from the building. Исследовано влияние зданий на общий гамма-фон. Гамма-фон между кирпичным зданием и полем, находящимся на расстоянии 100 м друг от друга (вдали от влияния других зданий), измерялось с помощью сцинтилляционного детектора. Были проведены измерения мощности амбиентного эквивалента дозы на разной высоте над почвой и на горизонтальном расстоянии от 0,1 м до 100 м с переменным шагом от здания. Был разработан новый подход для оценки вклада от почвы и здания в общий гамма-фон. Было получено, что гамма-излучение, вносимое зданиями, сильно влияет на суммарный гамма-фон на расстоянии до 2 м, на котором наблюдалось значительное уменьшение излучения в общем. Отмечено, что процент вносимого зданием вклада в общий гамма-фон, составляет от 4 до 29%. Это показывает, что большая часть фонового излучения в окружающей среде обеспечивается гамма-излучением почвы. Кроме того, годовая эквивалентная доза, полученная человеком, сидящим рядом со зданием, составила 0,09 мЗв, что выше, чем у взрослого, работающего далеко от здания (0,08 мЗв). Однако оба значения ниже среднемирового. Также было обнаружено, что лучшим местом для установки детектора гамма-излучения будет удаленное на 1,5 м от здания.

CONSUMPTION AND USE OF OXYGEN BY THE BODY OF PERSONS WITH CARDIOVASCULAR PATHOLOGY WITH CHANGES IN GEOMAGNETIC ACTIVITY

The aim of the study was to identify and evaluate the relationship between the indicators of solar activity, the content of magnesium in the blood and the level of oxygen utilization by tissues in men with different temperaments and anxiety, suffering from arterial hypertension. During the period of the study from 1995 to 2015, sick and healthy men were divided into equal groups with a predominance of choleric, sanguine, phlegmatic and melancholic temperament with high and low anxiety. The average annual values of the Wolf numbers, the radio emission of the Sun at a wavelength of 10,7 cm, atmospheric pressure, gamma background and air temperature were taken into account, and the content of magnesium and hemoglobin in the blood serum was determined. The oxygen concentration was determined by the calculated method. A statistically significant direct correlation has been established between the increase in solar activity (Wolf numbers, radio emission flux at a wavelength of 10.7 cm), on the one hand, and atmospheric pressure, air temperature, and the gamma background of the environment, on the other. Under the same environmental conditions, the content of magnesium in the blood and the level of oxygen utilization by the body tissues of patients with arterial hypertension decreased in the temperamental range from high- and low-anxiety sympathotonics (choleric and sanguine) to parasympathotonics (high- and low-anxiety phlegmatic and melancholic). During the study period, a statistically significant relationship was established between an increase in solar activity (Wolf numbers, radio emission flux), atmospheric pressure, air temperature, and gamma background, on the one hand, and a decrease in the content of magnesium in the blood, as well as the level of oxygen utilization by tissues in healthy high- and low-anxiety individuals and patients with arterial hypertension, regardless of temperament.

Estimation of the equivalent dose rate of gamma radiation in the open territory of the city of Voronezh

The aim of the study was to identify patterns of distribution of the magnitude of the the equivalent dose rate of gamma radiation in an open area of urban space, depending on the functional purpose of the inner-city territory and the type of artificial coating. Materials and methods. Measurements of the equivalent dose rate of gamma radiation (gamma background) in the city of Voronezh were carried out at 70 points, conventionally classified by functional use (industrial area, transport area, residential area, recreational area), as well as the type of coverage in open areas (granite stone blocks , asphalt pavement, paving slabs, open ground) For carrying out radiation monitoring, a highly sensitive portable search device was used – a search measuring gauge microprocessor ICP-PM1401MA. To assess the reliability of differences in the average values of the indicator by functional inner-city zones and types of artificial turf, the methods of parametric statistics (Student’s criterion) are used. Parametric methods of statistics in comparison with nonparametric methods allow statistically unambiguous interpretation of the results. There is no need to use other statistical tools in this regard. Results. The results of the evaluation of the radiation background show that the equivalent dose rate of gamma radiation (gamma background) in the city of Voronezh is from 0.06 to 0.14 µSv / h and it does not exceed the permissible value (0.3 µSv / h). Significant differences in the average values of indicators in the industrial, transport, residential functional areas in relation to the recreational area were not found (tcalc. < ttabl., P < 0.05). The maximum levels of gamma background (0.09-0.14 µSv / h) in the territory of the city of Voronezh were found in those places where processed natural stones (granite) were used for the improvement of the territory. When solving the problem of identifying the dependence of the indicator of the equivalent dose rate of gamma radiation in an open area of an inner-city space on the type of coating, in order to reduce uncertainties in the future, it is necessary to take into account the formulation of materials, especially the fraction of granite chips.

Variations of gamma-ray during thunderstorm by observations in Yakutsk

The paper presents the results of a study of the increase in the gamma background in the surface layer of the atmosphere during near thunderstorms in Yakutsk (based on the Cosmic Ray Spectrograph of the IKFIA SB RAS). To register the gamma background, scintillation detectors based on NaI (Tl) crystals with a size of 63mm x 63mm are used. The range of measured energies is 20-1900 keV. The detectors are closed from the sides and bottom with lead (5 cm) and placed in thermoboxes with a glass window. The detector is located on the roof of the Cosmic Ray Spectrograph building in Yakutsk. Also, synchronous registration of the atmospheric electric field strength was carried out using an atmosphere electric field – mill sensor (with measurement range +/- 50 kV / m).The data of continuous recording of an analog signal from a detector during the nearest thunderstorms of 2018 were considered. The analog signal from the gamma detector was fed to the first channel of the E20-10 ADC (L-Card) and recorded continuously on the computer hard disk for one hour (during a thunderstorm) in series of 10 minutes. A signal from an active broadband dipole P-10 antenna (0.9 kHz - 900 MHz bandwidth) was fed to the second channel and was also recorded in one file together with the signal from the gamma detector. Synchronous recording of signals from the gamma detector and from the antenna allows accurate timing of gamma photons to electromagnetic signals from nearby lightning. In the studied thunderstorms, based on the results of the analysis of the data obtained, statistically significant variations in the count rate and shapes of the spectrum of gamma – ray at the moment of lightning discharges were found.

RESPONSE OF THE CZECH RMN NETWORK TO THUNDERSTORM ACTIVITY

ABSTRACT Thunderstorm ground enhancement (TGE) is a phenomenon that enhances radiation background on the ground related to thunderstorm activity and charge structure of the thundercloud. On the other hand, the rise of gamma background is connected with precipitation by the washout of radon progeny from the atmosphere. In our analysis, we examined known enhancements of gamma background, previously attributed solely to radon progeny, using data from the Czech Radiation Monitoring Network (RMN) to investigate the enhancements with respect to thunderstorms and TGE phenomena. We also used radar precipitation data and data from the lightning location network to analyze their influences on the radiation background enhancement during three thunderstorm events that occurred in summer 2016 over the Czech Republic (Central Europe). We state that the RMN might have detected TGE over the Czech Republic.

PRE-ANTHROPIC AND PRESENT OUTDOOR GAMMA EQUIVALENT DOSE RATE OF THE HISTORIC CENTER OF ROME (ITALY)

The outdoor gamma background of the historic center of Rome was studied by in situ measurements and average values of the outcropping geological formations. The survey resulted in two maps of dose equivalent rate, related to pre-anthropic and present conditions. Presently, the average of the dose equivalent rate from outdoor gamma-ray field is equal to 0.31 μSv h−1, corresponding to an outdoor annual effective dose equivalent of 0.548 mSv a−1 and to an outdoor excess lifetime cancer risk [International Commission on Radiological Protection (ICRP). Recommendations of the ICRP, 21, 1/3, Publication 60, 1990] of 2.56 × 10−3. The originary radioactivity was enhanced by anthropic action up to a level of health risk comparable to that one deriving by fine particulate matter. The assessment of the evolution and dispersion of the outdoor gamma background offers a new perspective to study the urban architectural evolution. Such a mapping allows us to individuate mitigation actions and neighborhoods in which the monitoring of illicit trafficking of radioactive material can be efficiently tested.