Experimental Studies of Radiation-Protective Properties of a Modified Titanium Hydride

2022 ◽  
Vol 1049 ◽  
pp. 174-179
Author(s):  
A.A. Karnauhov ◽  
R.N. Yastrebinskii
Keyword(s):  
Gamma Radiation ◽  
Dose Rate ◽  
Titanium Hydride ◽  
Nuclear Power ◽  
Power Plants ◽  
High Efficiency ◽  
Experimental Studies ◽  
Point Sources ◽  
Relaxation Length ◽  
Protective Properties

The results of experimental studies of the protective properties of titanium hydride with respect to neutron and gamma radiation in order to determine the optimal conditions for their use in the composition of the structural radiation protection of the nuclear reactor are presented. The weakening of the basic functionals in the thickness of protection, including the density of fast, intermediate and thermal neutrons, and the dose rate of gamma radiation is established. The functions of weakening the density of neutron flow and the dose rate of gamma radiation are measured in the conditions of "barrier" geometry. Determination of the protective properties of the structure was carried out when the modified titanium hydride fraction was placed in aluminum containers with a filling coefficient of a volume of container 0.63. The relaxation lengths for all neutron groups are close and on average are 9.8 cm. The functions of weakening the dose rate of gamma radiation of point sources Cs-137 and Co-60 are exponential. The weakening of radiation occurs with a constant relaxation length. For energy 0.661 MeV, the relaxation length is 7.1 cm, for energy 1.25 MeV, the relaxation length is equal to 10.1 cm. On the basis of the experimental studies, the high efficiency of the modified fraction of titanium hydride was confirmed during its use in protecting nuclear power plants.

Weakening of neutron and gamma radiation from radioisotope sources by material based on modified titanium hydride

2021 ◽  
Vol 9 ◽  
pp. 24-33
Author(s):  
R. N. Yastrebinsky ◽  
◽  
G. G. Bondarenko ◽  
A. A. Karnauhov ◽  
◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Titanium Hydride ◽  
Experimental Studies ◽  
Calculated Data ◽  
Neutron Radiation ◽  
Amplitude Distribution ◽  
Fast Neutrons ◽  
Protective Properties ◽  
The Monte Carlo Method ◽  
Mcnp Program

The paper presents experimental studies of the radiation-protective properties of a material based on a modified titanium hydride with respect to gamma and neutron radiation of point radioisotope sources in barrier and continuous protection geometries. The calculated models of the problem of solving the radiation transfer equation for the Monte Carlo method and a comparative assessment of experimental and calculated results is given. The assessment of the amplitude distribution of gamma radiation in the thickness of the material of protection showed a significant reduction in the power of the equivalent dose of radiation gamma in the energy range of 180 – 250 keV, which is due to the effect of the Compton dispersion. The length relaxation of the dose of γ-radiation in 137Сs by the security material was 4.80 ± 0.18 cm. The length of the density relaxation of fast neutrons from the Pu-α-Be source was 6.20 ± 0.18 cm. Comparative analysis of the experimental and calculated data of the protective properties of the material based on modified titanium hydride In relation to radioisotope sources, showed high convergence of the results obtained and the adequacy of the application of the settlement model of the task for the MCNP program used.

scholarly journals MULTI-GROUP MODELING OF PROTECTION AGAINST NEUTRON AND GAMMA RADIATION BY MATERIALS BASED ON TITANIUM HYDRIDE

2020 ◽  
pp. 119-124
Author(s):  
Roman N. Yastrebinsky ◽  
Alexander A. Karnaukhov
Keyword(s):  
Gamma Radiation ◽  
Gamma Rays ◽  
Titanium Hydride ◽  
High Efficiency ◽  
Neutron Radiation ◽  
Fast Neutrons ◽  
Protective Efficiency ◽  
Relaxation Length ◽  
Group Modeling ◽  
Neutron Flux Density

The paper provides a comparative calculation of the radiation protective efficiency of various composite materials based on titanium hydride using multi-group modeling methods using the ANISN program. The calculations showed the high efficiency of titanium hydride composites with respect to neutron and gamma radiation. The relaxation length of the fast neutron flux density in titanium hydride materials is 5.1…7.0 cm. The spatial-energy distribution of neutron radiation in materials is formed by fast neutrons. The dose rate of gamma rays behind the material is determined mainly by capturing gamma rays arising in the initial layer of protection. Introduction to the composition of the protection of boron atoms reduces the level of capture gamma radiation, but does not affect the attenuation of fast neutrons.

Field Methods for Studying the Radiation Situation in the Area of the Belarusian NPP in the Pre-Operational Period

ANRI ◽  
2020 ◽  
pp. 31-44
Author(s):  
Aleksey Ekidin ◽  
Aleksey Vasil'ev ◽  
Maksim Vasyanovich ◽  
Evgeniy Nazarov ◽  
Mariya Pyshkina ◽  
...  
Keyword(s):  
Dose Rate ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Field Studies ◽  
Radiation Monitoring ◽  
Normal Operation ◽  
Construction Site ◽  
External Radiation ◽  
Field Methods

The article presents the results of field studies in the area of the Belarusian NPP in the pre-operational period. The «background» contents of gamma-emitting radionuclides in individual components of the environment are determined. The main array of dose rate measurements in the area of the NPP construction site is in the range 0.048 ÷ 0.089 μSv/h. External radiation in the surveyed area is formed at 96% due to 40K, 226Ra and 232Th. The information obtained can be used to correctly interpret the data of future radiation monitoring during normal operation of nuclear power plants.

Design, calibration, and application of an airborne gamma spectrometer system in Switzerland

Geophysics ◽  
1997 ◽  
Vol 62 (5) ◽  
pp. 1369-1378 ◽  
Author(s):  
Georg F. Schwarz ◽  
Ladislaus Rybach ◽  
Emile E. Klingelé
Keyword(s):  
Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Gamma Ray ◽  
Point Sources ◽  
Swiss Alps ◽  
Artificial Radioactivity ◽  
Radiation Level ◽  
Satellite Navigation System ◽  
Emergency Situations

Airborne radiometric surveys are finding increasingly wider applications in environmental mapping and monitoring. They are the most efficient tool to delimit surface contamination and to locate lost radioactive sources. To secure radiometric capability in survey and emergency situations, a new sensitive airborne system has been built that includes an airborne spectrometer with 256 channels and a sodium iodide detector with a total volume of 16.8 liters. A rack mounted PC with memory cards is used for data acquisition, with a GPS satellite navigation system for positioning. The system was calibrated with point sources using a mathematical correction to take into account the effects of gamma‐ray scattering in the ground and in the atmosphere. The calibration was complemented by high precision ground gamma spectrometry and laboratory measurements on rock samples. In Switzerland, two major research programs make use of the capabilities of airborne radiometric measurements. The first one concerns nuclear power plant monitoring. The five Swiss nuclear installations (four power plants and one research facility) and the surrounding regions of each site are surveyed annually. The project goal is to monitor the dose‐rate distribution and to provide a documented baseline database. The measurements show that all sites (with the exception of the Gösgen power plant) can be identified clearly on the maps. No artificial radioactivity that could not be explained by the Chernobyl release or earlier nuclear weapons tests was detected outside of the fenced sites of the nuclear installations. The second program aims at a better evaluation of the natural radiation level in Switzerland. The survey focused on the crystalline rocks of the Central Massifs of the Swiss Alps because of their relatively high natural radioactivity and lithological variability.

scholarly journals Lattice Defects and Exfoliation Efficiency of 6H-SiC via H2+ Implantation at Elevated Temperature

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5723
Author(s):  
Tao Wang ◽  
Zhen Yang ◽  
Bingsheng Li ◽  
Shuai Xu ◽  
Qing Liao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Nuclear Power ◽  
Power Plants ◽  
High Efficiency ◽  
Sample Surface ◽  
Lattice Defects ◽  
Transmission Electron ◽  
Sic Wafer

Silicon carbide (SiC) is an important material used in semiconductor industries and nuclear power plants. SiC wafer implanted with H ions can be cleaved inside the damaged layer after annealing, in order to facilitate the transfer of a thin SiC slice to a handling wafer. This process is known as “ion-cut” or “Smart-Cut”. It is worth investigating the exfoliation efficiency and residual lattice defects in H-implanted SiC before and after annealing. In the present paper, lattice damage in the 6H-SiC implanted by H2+ to a fluence of 5 × 1016 H2+/cm2 at 450 and 900 °C was investigated by a combination of Raman spectroscopy and transmission electron microscopy. Different levels of damage caused by dynamic annealing were observed by Raman spectroscopy and transmission electron microscopy in the as-implanted sample. Atomic force microscopy and scanning white-light interferometry were used to observe the sample surface morphology. Surface blisters and exfoliations were observed in the sample implanted at 450 °C and then annealed at 1100 °C for 15 min, whereas surface blisters and exfoliation occurred in the sample implanted at 900 °C without further thermal treatment. This finding can be attributed to the increase in the internal pressure of platelets during high temperature implantation. The exfoliation efficiency, location, and roughness after exfoliation were investigated and possible reasons were discussed. This work provides a basis for further understanding and improving the high-efficiency “ion-cut” technology.

The Effect of Elevated Temperatures and Nuclear Radiation on the Properties of Biological Shielding Concrete

2016 ◽  
Vol 677 ◽  
pp. 8-16 ◽  
Author(s):  
Jaroslava Koťátková ◽  
Jan Zatloukal ◽  
Pavel Reiterman ◽  
Jan Patera ◽  
Zbyněk Hlaváč ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Elevated Temperatures ◽  
Nuclear Radiation ◽  
Containment Vessel ◽  
Negative Impacts

The paper reviews the so far known information about the properties of biological shielding concrete used in the containment vessel of nuclear power plants (NPP) and its behaviour when exposed to radiation. The damage of concrete caused by neutron and gamma radiation as well as by the accompanying generation of heat is described. However, there is not enough data for the proper evaluation of the negative impacts and further research is needed.

Dynamic Processes in Vacuum Contact Devices of Robots for Vertical Motion in the Water Environment

2019 ◽  
Vol 20 (7) ◽  
pp. 417-421
Author(s):  
V. G. Gradetsky ◽  
M. M. Knyazkov ◽  
E. A. Semenov ◽  
A. N. Sukhanov
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Water Environment ◽  
Experimental Studies ◽  
Vertical Motion ◽  
Contact Device ◽  
Dynamic Processes ◽  
Simplified Models ◽  
Contact Devices ◽  
Air Ejector

The results of experimental investigation intended to improve movement conditions for pneumatic robots on vertical surfaces under water are discussed. Features of the movement of vacuum contact devices for the simulation of mathematical model of the vacuum contact device with surfaces under water are presented. The experimental studies made it possible to obtain additional data on the dynamics of attachment, to obtain transient processes for air-water flow through ejector and to correct the results obtained earlier. For the purpose of analytical study of dynamic processes occurring in the system of vacuum contact devices, and taking into account the complexity of the description of nonlinearities, linearized simplified models of the system "air ejector — contact device — water environment" were developed. Vacuum contact devices are designed to provide guaranteed contact with vertical surfaces, plane slopes or horizontal surfaces on which the underwater robot performs its movement, carrying out the prescribed technological tasks, for example, in dry wells of nuclear power plants, on the surfaces of ship hulls, on the surfaces of underwater structures. The models took into account the forces of adhesion to the surfaces under water — the forces from the pressure drop, the friction force, the contact and vacuum interaction, the elasticity of suction caps. As a result of the solution of the model problem, the values of mechanical parameters, as well as the values of vacuum and flow in the cavity of variable volume as functions of changing the gap between the end of the corrugated membrane and the surfaces are obtained explicitly. As a result of the study of dynamic processes occurring in simplified models of vacuum contact devices "air ejector — contact surface — water environment", the transient characteristics of the change in the operating forces and pressures over time, as well as the dependence of the normal and tangential components of the forces on the depth of immersion in water were obtained. The variants of the designs of vacuum contact devices with surfaces in the water environment are investigated, and the modernization of the laboratory test bench for testing vacuum contact devices under water is carried out.

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