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The paper presents the results of research and industrial tests of the effectiveness of the use of reagents for dust binding of dusty surfaces on the example of dry surfaces of tailings storage facilities of PJSC “InGZK” and PJSC “PivnGZK”. In the course of the research under contract No. 1205 dated 30.12.2021 between the Research Institute of Mining and Ore and PJSC "PivnGZK" from January 2022 until August 2022 two series of research on the properties of 16 reagents available on the market of Ukraine, which can be used for dust binding of dusting surfaces, were conducted, and a rating of reagents was formed according to the following indicators: stability of the protective layer; dust emission intensity; strength of the protective layer (ultrasonic method); the thickness of the protective layer; surface water absorption. According to the results of laboratory studies, the binding process of finely dispersed dust particles, which actively participate in the general process of dust cloud formation in the conditions of dust formation of dry surfaces of tailings storage facilities, was substantiated, and a general rating of reagents based on the effectiveness of their use was formed. [ABSTRACT FROM AUTHOR]

According to modern normative documents, the loading of postulated cracks in reactor vessels and standard specimens during crack resistance tests has a number of differences, namely: biaxiality of certain load configurations on the crack faces can change during non-isothermal, nonmonotonic processes under emergency modes of thermal shock, while crack front have a semi-elliptical shape of with relative depth ratio of 0.1–0.15. These factors prompt the development of an experimental technique to study crack resistance on non-standard type specimens. Cross-shaped (cruciform) bending specimens with a semi-elliptic surface crack and a through linear short crack, as well as model strip specimens with similar cracks in previous tests, were designed and studied for their static fracture strength. A method for monitoring fatigue crack initiation on a cross-shaped specimen by changes in its suppleness has been proposed. Evolution of semi-elliptic crack front shape at its initiation from a surface stress raiser under cyclic bending load has been investigated and the possibility of obtaining fatigue semi-elliptic crack of a certain configuration close to the postulated, according to the normative documents of cracks was shown. On the basis of test results, it was established that at temperature 20°C for 15Kh2NMFA-A steel, the standard conditions of a plane deformation in the used specimens were not satisfied, leading to the overestimated values of crack resistance since the steel ductile-brittle transition temperature T0 (according to the Master-curve) was much lower. It was shown that the obtained increase in crack resistance under equal-axial bending is comparable with literature sources for the conditions of large-scale yielding with uniaxial loading. [ABSTRACT FROM AUTHOR]

Proton boron capture therapy (PBCT) has emerged from particle acceleration research for enhancing the biological effectiveness of proton therapy. The mechanism responsible for the dose increase was supposed to be related to proton-boron fusion reactions ( 11 B + p → 3α + 8.7 MeV). There has been some experimental evidence that the biological efficiency of protons is significantly higher for boron-11-containing prostate or breast cancer cells. The aim of this study was to evaluate the sensitizing potential of sodium borocaptate (BSH) under proton irradiation at the Bragg peak of cultured glioma cells. To address this problem, cells of two glioma lines were preincubated with 80 or 160 ppm boron-11, irradiated both at the middle of 200 MeV beam Spread-Out Bragg Peak (SOBP) and at the distal end of the 89.7 MeV beam SOBP and assessed for the viability, as well as their ability to form colonies. Our results clearly show that BSH provides for only a slight, if any, enhancement of the effect of proton radiation on the glioma cells in vitro. In addition, we repeated the experiments using the Du145 prostate cancer cell line, for which an increase in the biological efficiency of proton irradiation in the presence of sodium borocaptate was demonstrated previously. The data presented add new argument against the efficiency of proton boron capture therapy when based solely on direct dose-enhancement effect by the proton capture nuclear reaction, underlining the need to investigate the indirect effects of the secondary alpha irradiation depending on the state and treatment conditions of the irradiated tissue., (© 2023. The Author(s).)