INFLUENCE OF SCATTERED NEUTRON RADIATION ON METROLOGICAL CHARACTERISTICS OF АТ140 NEUTRON CALIBRATION FACILITY

The field of high-energy gamma-ray for the calibration of radiation protection devices can be obtained by capturing thermal neutrons from titanium target (to 7 MeV) and nickel target (to 10 MeV). The aim of this work was to determine the metrological characteristics of capture gamma-ray fields from titanium target and nickel target obtained at the AT140 Neutron Calibration Facility to provide dosimetry up to 10 MeV.We have chosen energy intervals in which we can calibrate dosimetry devices taking into account the accompanying generation of gamma-ray neutrons by the fast neutron source 238PuBe, the capture radiation of collimator materials and capture radiation from targets.We measured air kerma rate with the aid of the reference AT5350 dosimeter with the ionization chamber TM32002. Using the Monte-Carlo simulation, we obtained the energy distribution of the air kerma rate for targets. We determined the geometric dimensions of the uniform field and the interval of operating distances of the facility.We investigated the metrological characteristics of capture gamma-ray fields from titanium target and nickel target obtained at the AT140 Neutron Calibration Facility for dosimetric radiation protection devices. We showed that in such fields it is possible to calibrate dosimetry devices in the extended energy range up to 10 MeV.

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A new type of defect structure in 124-superconducting oxide revealed by HREM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089779 ◽

1991 ◽

Vol 49 ◽

pp. 1092-1093

Author(s):

R. Sharma ◽

B.L. Ramakrishna ◽

N.N. Thadhani ◽

D. Hianes ◽

Z. Iqbal

Keyword(s):

Shock Wave ◽

Defect Structure ◽

Neutron Radiation ◽

Weak Links ◽

Defect Structures ◽

New Materials ◽

New Type ◽

Current Densities ◽

Processing Techniques ◽

Microstructural Studies

After materials with superconducting temperatures higher than liquid nitrogen have been prepared, more emphasis has been on increasing the current densities (Jc) of high Tc superconductors than finding new materials with higher transition temperatures. Different processing techniques i.e thin films, shock wave processing, neutron radiation etc. have been applied in order to increase Jc. Microstructural studies of compounds thus prepared have shown either a decrease in gram boundaries that act as weak-links or increase in defect structure that act as flux-pinning centers. We have studied shock wave synthesized Tl-Ba-Cu-O and shock wave processed Y-123 superconductors with somewhat different properties compared to those prepared by solid-state reaction. Here we report the defect structures observed in the shock-processed Y-124 superconductors.

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Impact assessment of the flow switch on the metrological characteristics of the standard units of mass and liquid volume in the flow, mass and volume liquid flow

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2019-4-42-47 ◽

2019 ◽

pp. 42-47 ◽

Cited By ~ 2

Author(s):

R. A. Korneev ◽

A. R. Tukhvatullin ◽

V. A. Fafurin ◽

A. V. Shchelchkov

Keyword(s):

Impact Assessment ◽

Liquid Flow ◽

Metrological Characteristics ◽

Liquid Volume ◽

Flow Switch

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National primary standard machine of Shore D hardness scale for metals and Leeb hardness scales

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-2-6-10 ◽

2020 ◽

pp. 6-10

Author(s):

A.E. Aslanyan ◽

E.G. Aslanyan ◽

S.M. Gavrilkin ◽

A.S. Doynikov ◽

A.N. Shchipunov

Keyword(s):

Measurement Uncertainty ◽

Primary Standard ◽

Metrological Characteristics ◽

National Primary Standard ◽

Hardness Scale ◽

Leeb Hardness

The article presents the results of studies to improve the National primary standard machine for hardness of metals on the shore D scale GET 161-2001, which were performed in FSUE “VNIIFTRI” from 2016 to 2018 in accordance with the technical task of Rosstandart.The improvement was carried out in order to ensure the uniformity of hardness measurements on the Leeb scales. The created new parts of the primary standard machine, which are settings for reproducing hardness numbers on the Leeb scales, are considered. Metrological characteristics of the upgraded and adopted National primary standard machine (GET 161-2019) were investigated, the budget of measurement uncertainty was calculated for reproducing hardness numbers on the Leeb scales.

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