INDOOR RADON-222 CONCENTRATION MEASUREMENTS AT FACULTY OF EDUCATION, YAFEA, ADEN UNIVERSITY, YEMEN, USING CR-39 NUCLEAR TRACK DETECTOR

In this study, the activity concentration of indoor radon-222, annual effective dose, exhalation rate of radon, and relative risk of lung cancer are reported for different indoor buildings (students' dorms, teachers' dorms, offices, laboratories, library, lecture halls, and materials store) in Faculty of Education, Yafea, Aden University, Yemen. Sealed-can technique based on CR-39 nuclear tracks detector was distributed to radon gas survey. Twenty six radon detectors were mounted in seven buildings. The Radon measurements were performed for 90 days between December 2020 and March 2021. The results showed that the radon concentration ranges from 23,18 Bq m-3 to 66.49 Bq m-3 with an average value 35.86 Bq m-3, the annual effective dose ranges from 0.6 mSv y-1 to 1.639 mSv y-1 with an average value 0.979 mSv y-1, the exhalation rate ranges from 10.03 m Bq m-2 h-1 to 28.50 mBq m-2 h-1 with an average value 15.68 mBq m-2 h-1 and relative risk of lung cancer ranges from 1.02 to 1.06 with an average value 1.03. A strong correlation coefficient has been observed between radon concentration and radon exhalation rate. All of the values revealed in the study were of nominal state (that is less than allowed global values) and thus have no risk for the population living in these buildings.

Statistical Characterization of Damage of Different Surface P-Wave Velocity Sets under Dynamic Load and Study on Overall Radon Detection Consistency

On the basis of reviewing the existing research status of cumulative damage of the rock mass and summarizing the existing engineering application fields of radon, this paper attempts to apply radon detection technology to the research field of rock damage mechanics so as to monitor the evolution process of cumulative damage of the rock mass. Based on the above research purposes, a test device for detecting cumulative damage of radioactive rocks by surface radon gas was designed, and the test results were obtained by integrating the system to implement the test scheme. Due to the limitation of the nonmetallic ultrasonic detector, a single blasting damage value of 25 detection points appears after a single blasting measurement, which is a surface longitudinal wave velocity characterization damage set, while the surface radon exhalation rate in the subsequent analysis process is an overall characterization value; that is, the existence of damage directly affects the whole body radon exhalation rate of the test block, and the data dimensions of the two are different. In order to solve this problem, we try to introduce three data evaluation methods, the average weighting method, grey prediction method, and K-means clustering algorithm, and compare the feasibility of these three methods. It is proved that there is a certain linear relationship between the radon exhalation rate and the cumulative damage, which further verifies the feasibility of using radon to detect cumulative damage. The results show that the cumulative damage of loaded radioactive rock test blocks can be reflected by surface radon detection technology, and finally, the correlation between the cumulative damage characteristics and the continuous change of the body radon exhalation rate is obtained. Based on the correlation, the body radon exhalation rate is introduced into the field of fractured rock mass damage characterization, which is mutually improved with common monitoring methods such as acoustic emission and microseismic monitoring, supplementing and enriching the means of rock mass damage evolution characterization, providing a theoretical basis for finely describing the whole process of fracture closure and initiation, and finally accurately ensuring the stability of surrounding rock under the action of deep underground engineering excavation disturbance.

Assessment of Radon, Radium, and Uranium Concentrations in Decorative Materials (Used to walls) Samples in Iraqi Markets

In present study, natural alpha emitters (222Rn, 226Ra, and 238U) were tested in decorative materials used as walls collected from different Iraqi local markets by CR-39 detectors that it was purchased from TASTRAK Analysis System. Annual effective dose and radon exhalation rate were calculated. The results obtained showed that the range and average value of 222Rn concentrations in air container were 7.94 – 738.10 Bq/m3 and 252.38±37.63 Bq/m3, while 222Rn concentrations in in sample were 45.73– 4252.99 Bq/m3 and 1454.25±216.84 Bq/m3. The ranged of 226Ra and 238U concentrations were 0.010- 1.000 Bq/kg, with an average value 0.278±0.04 Bq/kg and 0.01- 1.24 ppm, with an average value 0.344±0.05 ppm, respectively. The results obtained showed that the range and average value of annual effective dose in mSv/y were 0.2 –18.62 and 6.29±0.95. Also, it is found that the mass exhalation rate as well as surface exhalation rate were 8.38±1.33 mBq/kg.day and 240.77±36.56 mBq/m2.day, respectively. The data of 222Rn concentration (in air container), and annual effective dose in some samples of the present study were higher than the global limit range (200-300 Bq/m3), and (3-10 mSv/y) according to ICRP. While, all results of 226Ra, and 238U concentrations as well as the mass with surface exhalation rate were within the permissible limits that suggested by UNSEAR, and ICRP. Then, it can be concluded that the most samples of decorative materials which used as walls according to radiation scope no causes health risk.

Evaluation of the clinical effectiveness of the osteopathic correction in children with chronic bronchitis in a sanatorium

Introduction. Possible causes of chronic bronchitis are anatomically incorrect location of internal organs, the presence of congestion, impaired blood circulation, impaired mobility level, disorders of innervation and metabolic processes in the respiratory organs, decreased mobility of the chest, tension of the thoracic diaphragm, imbalance of the myofascial system, diseases of the spine (osteochondrosis, scoliosis, etc.). These disorders and dysfunctions are extremely rarely taken into account in the prescription of conventional therapy regimens in children with chronic bronchitis. At the same time, it is known that many drugs and various therapeutic effects in some cases are not able to give long-term remission and recovery. This causes the need to search for new methods of treating chronic bronchitis in children, one of which could be osteopathic correction. At the same time, in the available literature sources, there is very little information on this problem, and the presented data are sometimes contradictory.The aim of the study is to evaluate the clinical effectiveness of osteopathic correction in the treatment of children with chronic bronchitis in a sanatorium.Materials and methods. The controlled randomized trial was conducted from June 2020 to April 2021. The study included 40 patients with chronic bronchitis at the age from 6 to 16 years, 24 boys, 16 girls, who were undergoing sanatorium-resort treatment in the children′s sanatorium «Raduga» (Sterlitamak). Depending on the applied treatment method, the patients were divided by simple randomization into two comparable groups (main and control) of 20 people each. All patients received sanatorium resort treatment, which included physical therapy, halotherapy, inhalations, phytotherapeutic procedures. Patients of the main group, in addition to the above-described therapy, received osteopathic correction. In total, 2 sessions were carried out with an interval of 7 days. All patients, regardless of the group, before the start of treatment, as well as after the completion of the therapy course, underwent an assessment of the osteopathic status, chest excursion and respiratory function.Results. During the treatment with inclusion of osteopathic correction, in patients of the main group, there is a significant decrease in the frequency of detection of somatic dysfunctions (global rhythmogenic disorder, neck region, chest region), as well as a significant positive dynamics of indicators characterizing the external respiration function (chest excursion, forced vital capacity of lungs, peak exhalation rate), compared with patients receiving only conventional therapy. Positive changes in the chest excursion and peak exhalation rate against the background of osteopathic correction persist reliably even 3 months after the completion of the therapy course, and it allows to suppose the prolonged effect of the therapy.Conclusion. The study showed that osteopathic correction increases the clinical effectiveness of the conventional methods of sanatorium resort treatment for pediatric patients with chronic bronchitis. This allows to recommend the inclusion of osteopathic methods of correction in complex treatment programs for this group of patients in a sanatorium.

Radon emission fluctuation as a result of biochar application into the soil

The presented research was focused on the analysis of the impact of biochar application into the soil on the radon exhalation process as a new issue of radiation protection in agriculture. Field measurements of the radon exhalation rate utilizing two methods—active and passive as well as laboratory measurements of the radon emanation coefficient were performed. In laboratory a soil samples with sunflower husk biochar were analysed using the accumulation chamber technique. At the final step the assessment of the effective dose for humans coming from radon exhalation from soil depending on biochar dose applied were evaluated. The doses of biochar applied in the analysed experimental fields were 0, 20, 40, 60, 80, and 100 Mg ha−1. The results show that biochar application into the soil contribute to a decrease in the emanation coefficient from a value around 7% to less than 2% with a simultaneous decrease in the radon exhalation rate from 4.4 to 14.8 mBq m−2 s−1 when the biochar dose increase from 0 to 100 Mg ha−1.

Physical-mechanical Properties and Radon Exhalation of Fiber-reinforced Uranium Tailings Geopolymer Solidified Bodies

Uranium tailing ponds are a potential major source of radioactive pollution. Solidification treatment of uranium tailings can control the diffusion and migration of radioactive elements in uranium tailings to safeguard the surrounding ecological environment. Literature review and field investigation were conducted in this study prior to fabricating 11 solidified uranium tailings samples with different proportions with PVA fiber, basalt fiber, metakaolin, and fly ash. The samples’ pore structure, volume resistivity, compressive strength, and radon exhalation rate variations were analyzed. The pore size of the solidified samples is mainly between 1–50 nm, the pore volume is between 0.726–1.750 cm3/g, the volume resistivity is between 1411.33-1937.33 Ω·m, and the compressive strength is between 20.61–36.91 MPa. The radon exhalation rate is between 0.0397–0.0853 Bq·m2·s− 1, which is lower than the national standard. Based on a comprehensive analysis of the physical and mechanical properties and radon exhalation rate of the solidified samples, the basalt fiber is found to outperform PVA fiber overall. The solidification effect is optimal when the 0.6% basalt fiber is added.