Neutron Radiography Facility at IBR-2 High Flux Pulsed Reactor: First Results

Duliu

et al. 2020

Sci Rep

Two analytical methods based on the neutrons high penetrability, i.e. neutron diffraction (ND) and neutron computed tomography (NCT) were used to investigate the structure of the aragonitic skeleton of an exemplar/sample of Dipastraea pallida (Dana 1846), a modern hermatypic coral. ND was used to reconstruct the orientation distribution function (ODF) of the crystalline fibrils which compose the coral skeleton. Accordingly, 684 ND spectra were analyzed using the Rietveld method. The result confirmed the aragonite as the sole mineral component of coral skeleton, allowing to recalculate the ODF of aragonite fibrils and to represent it by means of (100), (010) and (001) crystallographic planes pole figures (PF). Experimental PF showed a remarkable similarity with PF recalculated by considering that all aragonite fibrils are oriented either along the growth axis of polyp cups or perpendicular to this direction. This result confirmed the previous observations based on optical microscopy, proving at the same time the availability of ND for such types of investigations. In turn, NCT evidenced the individual polyp cups, their interlocked 3D rigid porous structure as well as a periodic variation of density which could be attributed to a seasonal influence of the marine environment. Different from the classical X-ray computed tomography, the NCT, in view of neutron high cross-section for hydrogen, demonstrated the presence of a small amount of organic matter, otherwise transparent for X-and gamma rays.

“…This is significantly lower then X-ray CT, whose resolution can be better than 30 μm. More details on this tomographic system can be found in 41,42 .…”

Section: Methods Coralsmentioning

confidence: 99%

The structure of scleractinian coral skeleton analyzed by neutron diffraction and neutron computed tomography

Ivankina

Duliu

et al. 2020

Sci Rep

“…The neutron tomography experiments were performed at the neutron radiography and tomography facility [31,32] on the IBR-2 high-flux pulsed reactor. The detector system based on high sensitivity camera with HAMAMATSU CCD chip was used to a collection of neutron radiography images.…”

Section: Methodsmentioning

confidence: 99%

A structural insight into the Chelyabinsk meteorite: neutron diffraction, tomography and Raman spectroscopy study

Козленко

Kirillov³

et al. 2019

SN Appl. Sci.

The internal structural organization and phase composition of a fragment of the Chelyabinsk meteorite have been studied using neutron diffraction, tomography methods, optical microscopy, and Raman spectroscopy. The bulk mineral composition of the meteorite and spatial distribution of different components were determined. In addition to previously found phases of olivine, orthopyroxene, plagioclase and troilite, the obtained data of optical microscopy and neutron diffraction provide evidence of the presence of kamacite phase in the studied meteorite fragment. The heterogeneous distribution of the iron in the olivine and orthopyroxene phases was observed, the morphological calculations were used to analyze the spatial arrangement of metal components.

“…Neutron tomography experiments were performed at the neutron radiography and tomography facility (Kozlenko et al. , ) and placed on beamline 14 of the IBR‐2 high‐flux pulsed reactor. The IBR‐2 reactor provides a thermal neutron beam with wavelengths ranging from ~0.2 to 8 Å and spectral distribution maximum of ~1.8 Å.…”

Section: Methodsmentioning

confidence: 99%

“…The spatial resolution capabilities of the neutron tomography facility have some restrictions on the minimum size of a resolved item up to 270 microns or 0.02 mm 3 (Kozlenko et al. , ).…”

Section: Methodsmentioning

confidence: 99%

A neutron tomography study of the Seymchan pallasite

Meteorit & Planetary Scien

Козленко

Лукин

et al. 2018

The internal structure of an olivine‐rich fragment of the Seymchan meteorite was studied using neutron tomography. The differences in the neutron attenuation coefficients of constituent elements of the studied pallasite and the application of modern mathematical algorithms for a three‐dimensional (3‐D) imaging data analysis allow us to obtain a spatial distribution of different meteorite components. The heterogeneous distribution of the nickel in the metal phase was observed. In addition to the resulting 3‐D model of the Seymchan meteorite, the distributions of the volumes, average sizes, and shape‐related parameters of the FeNi metal component and olivine grains were obtained.