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.

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.

High efficiency resonance scintillators for 23.8 keV recoilless gamma-rays of 119mSn

1983 ◽  
Vol 206 (3) ◽  
pp. 581-586 ◽  
Author(s):  
I.G. Mandjukov ◽  
B.V. Mandjukova ◽  
V.G. Jelev ◽  
N.V. Markova
Keyword(s):  
Gamma Rays ◽  
High Efficiency

Neutron Radiation Effects on Lubricants and O-Rings for Target and Accelerator Applications

2021 ◽  
Vol 1024 ◽  
pp. 127-133
Author(s):  
Matteo Ferrari ◽  
Aldo Zenoni ◽  
Yong Joong Lee ◽  
Alberto Andrighetto
Keyword(s):  
Gamma Radiation ◽  
Radiation Damage ◽  
Radiation Effects ◽  
Nuclear Reactor ◽  
Neutron Radiation ◽  
Radioactive Isotopes ◽  
Structural Level ◽  
Radiation Resistant ◽  
Under Construction ◽  
Neutron Radiation Effects

Lubricants and O-rings are necessarily used for the construction of many accelerator-driven facilities as spallation sources or facilities for the production of radioactive isotopes. During operation, such component will absorb high doses of mixed neutron and gamma radiation, that can degrade their mechanical and structural properties. Experimental radiation damage tests of these components are mandatory for the construction of the facility. Methodologies for irradiation in nuclear reactor mixed fields and post-irradiation examination of lubricating oils, greases and O-rings were developed and are here presented. Samples were characterized with standard mechanical and physical-chemical tests. Parametric studies on the dose rate effects have been performed on O-rings. A case studies for a specific O-ring application in a gate valve has been developed. Some of the tested samples showed a dramatic change of their properties with dose, while others remain stable. Results were collected on nine commercial greases, on one oil and on four commercial elastomeric O-rings. The most radiation resistant among the selected products are now considered for application in facilities under construction. The main mechanisms of neutron and gamma radiation damage on these polymers were investigated at the mechanical and structural level.

scholarly journals Testing the protective efficiency of personal respiratory protection devices in radiologically contaminated environments

2013 ◽  
Vol 28 (1) ◽  
pp. 102-107
Author(s):  
Dusan Rajic ◽  
Negovan Ivankovic ◽  
Natasa Ivankovic ◽  
Marina Ilic ◽  
Zeljko Senic ◽  
...  
Keyword(s):  
High Efficiency ◽  
Face Mask ◽  
Depleted Uranium ◽  
Test Substance ◽  
Respiratory Protection ◽  
Protective Efficiency ◽  
Submicron Scale ◽  
Protection Devices ◽  
Protective Mask

The use of ammunition primed with depleted uranium is one of the hallmarks of modern combat operations, resulting in environmental contamination by particles of depleted uranium and uranium oxide, scattered around in the form of submicron-scale aerosols. This paper examined the protective effectiveness of the Serbian military's M3 protective face mask in relation to the presence of airborne depleted uranium and its by-products. Sodium chloride in solid aerosol form was used as a test substance and adequate physical simulator of such radioactive aerosols because its granulometric (particle) size distribution met the requirements of suitability as a simulator. Determination of aerosol concentration was carried out by flame photometry method, whilst granulometric distribution was determined by an electric particles analyzer. It was established that the total internal leakage of the M3 protective mask was as much a function of the penetration of particles through the combined M3 filter as of the leaks along the fitting line of the user's face mask and the inhalation valve. In terms of its protective effect against aerosols of depleted uranium and associated oxides, the Serbian M3 protective mask was determined to be of high efficiency and physiological suitability.

scholarly journals IV. Effect of 60Co gamma rays on survival rate of China aster plants (Callistephus chinensis Nees) in M1 generations - under field conditions

2013 ◽  
Vol 35 (2) ◽  
pp. 277-283
Author(s):  
A. Wosińska
Keyword(s):  
Survival Rate ◽  
Gamma Radiation ◽  
Gamma Rays ◽  
Lethal Effect ◽  
Field Conditions ◽  
Considerable Decrease ◽  
Planting Time ◽  
Variety Effect ◽  
China Aster ◽  
Different Doses

Studies were undertaken on the effect of different doses of gamma radiation on survival rate of plants (germinated from irradiated seeds) for 5 China aster varieties specified at florescence time. During their growth under field conditions (from planting time to blooming) lethal effect of the radiation occurred in plants of all varieties and its level depended on dose and variety. Effect of 3 kR and 6 kR doses differed depending on variety and was not always harmful, but following irradiation with doses exceeding 6 kR a considerable decrease in survival rate was observed. Radioresistance of studied varieties - measured both: by LD<sub>50</sub> and LD<sub>l00</sub> - differed; depending on variety, LD<sub>50 </sub>and LD<sub>l00</sub> values fluctuated: from 6 to 9 kR and 12 to 15 kR respectively.

Late Effects of Fast Neutrons and Gamma-Rays in Mice as Influenced by the Dose Rate of Irradiation: Induction of Neoplasia

1970 ◽  
Vol 41 (3) ◽  
pp. 467 ◽  
Author(s):  
A. C. Upton ◽  
M. L. Randolph ◽  
J. W. Conklin ◽  
M. A. Kastenbaum ◽  
M. Slater ◽  
...  
Keyword(s):  
Dose Rate ◽  
Gamma Rays ◽  
Late Effects ◽  
Fast Neutrons

Evaluation of the effect of gamma rays on the venom of Vipera lebetina by biochemical study

2003 ◽  
Vol 81 (12) ◽  
pp. 1110-1117 ◽  
Author(s):  
Nouara Bennacef-Heffar ◽  
Fatima Laraba-Djebari
Keyword(s):  
Gamma Radiation ◽  
Gamma Rays ◽  
Biochemical Characterization ◽  
Biochemical Study ◽  
Gel Filtration ◽  
Public Health Problem ◽  
Phospholipase A ◽  
Snake Bites ◽  
Vipera Lebetina

Snake bites represent a serious public health problem in many areas of the world. In Algeria, two widespread snakes are Vipera lebetina and Cerastes cerastes. Vipera lebetina venom causes local hemorrhage and necrosis, and it may lead to permanent limb loss. The principal causes of mortality after snakebites are acute renal failure and hemorrhage, which occur not only locally, at the site of the bite, but also systemically, contributing to the cardiovascular shock characteristic of severe envenomation. Gamma radiation has been shown to be effective for attenuating venom toxicity. Vipera lebetina venom was irradiated with two doses of gamma rays (1 and 2 kGy) from a 60Co source, and the venom's toxic, enzymatic, and structural properties were analyzed. Intraperitoneal injection of the irradiated venoms (100–500 µg/20 g mouse body mass) revealed a significant decrease of the toxicity. Irradiated venoms with 1 and 2 kGy doses were four and nine times less toxic, respectively, than the native venom. A biochemical characterization of in vitro enzymatic activities was performed. Vipera lebetina displayed in vitro caseinolytic, amidolytic, esterasic, coagulant, and phospholipase A2 activities. Caseinolytic, amidolytic, esterasic, and coagulative activities were reduced for the irradiated venoms; only phospholipase A2 activity was abolished in the irradiated venom with a dose of 2 kGy. The native and irradiated venoms were separated by gel filtration and electrophoresis. Chromatographic and electrophoretic profiles were drastically changed as compared with the native venom. Vipera lebetina venom detoxified by gamma rays was used for active immunization, and the presence of antibody in the immune sera was detected by ELISA. The immunogenic properties were preserved and the antisera obtained with the irradiated venoms could cross-react. Antisera were able to neutralize the toxic effect of V. lebetina native venom. These results indicate that irradiation of V. lebetina venom with a dose of 2 kGy can promote a significant detoxification, keeping the immunological properties intact.Key words: Vipera lebetina venom, gamma radiation, enzymes, detoxification, immune sera, immunoreactivity.

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