scholarly journals On the Genesis of Artifacts in Neutron Transmission Imaging of Hydrogenous Steel Specimens

2020 ◽  
Vol 6 (4) ◽  
pp. 22
Author(s):  
Beate Pfretzschner ◽  
Thomas Schaupp ◽  
Andreas Hannemann ◽  
Michael Schulz ◽  
Axel Griesche
Keyword(s):  
Surface Roughness ◽  
Edge Effect ◽  
Neutron Radiography ◽  
Neutron Radiation ◽  
Neutron Transmission ◽  
Functional Correlation ◽  
Transmission Imaging ◽  
Detector Distance ◽  
Imaging Artifacts ◽  
Scattered Neutrons

Hydrogen-charged supermartensitic steel samples were used to systematically investigate imaging artifacts in neutron radiography. Cadmium stencils were placed around the samples to shield the scintillator from excessive neutron radiation and to investigate the influence of the backlight effect. The contribution of scattered neutrons to the total detected intensity was investigated by additionally varying the sample-detector distance and applying a functional correlation between distance and intensity. Furthermore, the influence of the surface roughness on the edge effect due to refraction was investigated.

scholarly journals Bragg-edge elastic strain tomography forin situsystems from energy-resolved neutron transmission imaging

2017 ◽  
Vol 1 (5) ◽  
Author(s):  
J. N. Hendriks ◽  
A. W. T. Gregg ◽  
C. M. Wensrich ◽  
A. S. Tremsin ◽  
T. Shinohara ◽  
...  
Keyword(s):  
Elastic Strain ◽  
Neutron Transmission ◽  
Transmission Imaging

scholarly journals High Spatial Resolution Neutron Transmission Imaging Using a Superconducting Two-Dimensional Detector

2021 ◽  
pp. 1-1
Author(s):  
Hiroaki Shishido ◽  
Kazuma Nishimura ◽  
The Dang Vu ◽  
Kazuya Aizawa ◽  
Kenji M Kojima ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Two Dimensional ◽  
Neutron Transmission ◽  
Transmission Imaging

scholarly journals Mapping of axial plastic zone for roller bearing overloads using neutron transmission imaging

2018 ◽  
Vol 156 ◽  
pp. 103-112 ◽  
Author(s):  
A. Reid ◽  
I. Martinez ◽  
M. Marshall ◽  
T. Minniti ◽  
S. Kabra ◽  
...  
Keyword(s):  
Plastic Zone ◽  
Roller Bearing ◽  
Neutron Transmission ◽  
Transmission Imaging

Investigation of a Lithium Indium Diselenide detector for neutron transmission imaging

2014 ◽  
Author(s):  
Eric Lukosi ◽  
Elan Herrera ◽  
Ashley C. Stowe ◽  
Robert Milburn ◽  
Dylan Richardson ◽  
...  
Keyword(s):  
Neutron Transmission ◽  
Transmission Imaging

scholarly journals Spatiotemporal distribution of nitrogen dioxide within and around a large-scale wind farm – a numerical case study

2017 ◽  
Vol 17 (23) ◽  
pp. 14239-14252 ◽  
Author(s):  
Jingyue Mo ◽  
Tao Huang ◽  
Xiaodong Zhang ◽  
Yuan Zhao ◽  
Xiao Liu ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Nitrogen Dioxide ◽  
Wind Turbine ◽  
Wind Power ◽  
Edge Effect ◽  
Air Pollutants ◽  
Wind Farm ◽  
Roughness Length ◽  
Atmospheric Transport ◽  
Surface Roughness Length

Abstract. As a renewable and clean energy source, wind power has become the most rapidly growing energy resource worldwide in the past decades. Wind power has been thought not to exert any negative impacts on the environment. However, since a wind farm can alter the local meteorological conditions and increase the surface roughness lengths, it may affect air pollutants passing through and over the wind farm after released from their sources and delivered to the wind farm. In the present study, we simulated the nitrogen dioxide (NO2) air concentration within and around the world's largest wind farm (Jiuquan wind farm in Gansu Province, China) using a coupled meteorology and atmospheric chemistry model WRF-Chem. The results revealed an edge effect, which featured higher NO2 levels at the immediate upwind and border region of the wind farm and lower NO2 concentration within the wind farm and the immediate downwind transition area of the wind farm. A surface roughness length scheme and a wind turbine drag force scheme were employed to parameterize the wind farm in this model investigation. Modeling results show that both parameterization schemes yield higher concentration in the immediate upstream of the wind farm and lower concentration within the wind farm compared to the case without the wind farm. We infer this edge effect and the spatial distribution of air pollutants to be the result of the internal boundary layer induced by the changes in wind speed and turbulence intensity driven by the rotation of the wind turbine rotor blades and the enhancement of surface roughness length over the wind farm. The step change in the roughness length from the smooth to rough surfaces (overshooting) in the upstream of the wind farm decelerates the atmospheric transport of air pollutants, leading to their accumulation. The rough to the smooth surface (undershooting) in the downstream of the wind farm accelerates the atmospheric transport of air pollutants, resulting in lower concentration level.

scholarly journals Untersuchung von Feuchtetransport mittels numerischer Modellierung und Neutronentransmissionsanalyse / Study of Moisture Transport by Numerical Modeling and Neutron Transmission Analysis

1997 ◽  
Vol 3 (4) ◽  
pp. 355-370
Author(s):  
H. Pleinert ◽  
H. Sadouki ◽  
F.H. Wittmann
Keyword(s):  
Moisture Transport ◽  
Building Materials ◽  
Transport Model ◽  
Neutron Radiography ◽  
High Sensitivity ◽  
Moisture Distribution ◽  
Transfer Model ◽  
Porous System ◽  
Neutron Transmission ◽  
Good Spatial Resolution

Abstract Moisture transport in porous building materials is described by a transport model that expresses the action of the several transport mechanisms of liquid water and water vapor in the porous system by a single material specific transfer coefficient. This parameter has to be determined by experimental measurement of moisture distributions inside samples exposed to known initial and boundary conditions. Neutron radiography is employed as experimental method because of its high sensitivity and good spatial resolution. The moisture distribution is determined from the raw data obtained in the measurement by a calculation procedure based on a signal transfer model of the neutron transmission. This approach is illustrated by two examples: the drying of a plain brick sample and the drying of a composite sample consisting of two brick elements separated by a layer of mortar.

scholarly journals Neutron transmission imaging with a portable D-T neutron generator

2021 ◽  
Author(s):  
Phillip Kerr ◽  
Nerine Cherepy ◽  
Jennifer Church ◽  
Gary Guethlein ◽  
James Hall ◽  
...  
Keyword(s):  
Neutron Generator ◽  
Neutron Transmission ◽  
Transmission Imaging

scholarly journals Spectroscopic fast neutron transmission imaging in a treaty verification setting

AIP Advances ◽  
2018 ◽  
Vol 8 (1) ◽  
pp. 015205 ◽  
Author(s):  
K. Ogren ◽  
J. Nattress ◽  
I. Jovanovic
Keyword(s):  
Fast Neutron ◽  
Neutron Transmission ◽  
Treaty Verification ◽  
Transmission Imaging
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