The pore space arrangement in podzolic horizons of loamy soils (analysis of 2D AND 3D images)

A comparative analysis of 2D (in thin sections) and 3D (X-ray CT) images allowed obtaining new data about the pore space arrangement in the EL horizon of soddy podzolic soils. The 3D images of the soil mass and the pore space have been made by reconstruction via computer using a great number of 2D shady X-ray projections. It is shown that the EL horizon reveals not only horizontal fissured pores between platy aggregates but also many isolated vesicular pores of unknown genesis. As dinstinct from the podzolic horizon such pores are singly met in the soil-forming mantle loam (C horizon). The major pores with rounded edges are represented by recent and relic root holes. The obtained data serve as an additional information on the podzolic horizon configuration in soddy podzolic soils on the whole and the pore space in these horizons in particular. Thanks to this study iy is reasonable to conclude that the information on genetic differences in the configuration of pedogenic and lithogenic horizons of the soddy podzolic soils is expanded.

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Spectral Tomography for 3D Element Detection and Mineral Analysis

Minerals ◽

10.3390/min11060598 ◽

2021 ◽

Vol 11 (6) ◽

pp. 598

Author(s):

Jose R. A. Godinho ◽

Gabriel Westaway-Heaven ◽

Marijn A. Boone ◽

Axel D. Renno

Keyword(s):

Energy Spectrum ◽

3D Imaging ◽

X Rays ◽

3D Images ◽

Characterization Methods ◽

X Ray ◽

Additional Information ◽

Mineral Phases ◽

Spectral Computed Tomography

This paper demonstrates the potential of a new 3D imaging technique, Spectral Computed Tomography (sp-CT), to identify heavy elements inside materials, which can be used to classify mineral phases. The method combines the total X-ray transmission measured by a normal polychromatic X-ray detector, and the transmitted X-ray energy spectrum measured by a detector that discriminates between X-rays with energies of about 1.1 keV resolution. An analysis of the energy spectrum allows to identify sudden changes of transmission at K-edge energies that are specific of each element. The additional information about the elements in a phase improves the classification of mineral phases from grey-scale 3D images that would be otherwise difficult due to artefacts or the lack of contrast between phases. The ability to identify the elements inside the minerals that compose ore particles and rocks is crucial to broaden the application of 3D imaging in Earth sciences research and mineral process engineering, which will represent an important complement to traditional 2D imaging mineral characterization methods. In this paper, the first applications of sp-CT to classify mineral phases are showcased and the limitations and further developments are discussed.

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Carbon speciation in organic fossils using 2D to 3D x-ray Raman multispectral imaging

Science Advances ◽

10.1126/sciadv.aaw5019 ◽

2019 ◽

Vol 5 (8) ◽

pp. eaaw5019 ◽

Cited By ~ 9

Author(s):

Rafaella Georgiou ◽

Pierre Gueriau ◽

Christoph J. Sahle ◽

Sylvain Bernard ◽

Alessandro Mirone ◽

...

Keyword(s):

Chemical Speciation ◽

Multispectral Imaging ◽

Unsolved Problem ◽

3D Images ◽

X Ray ◽

Plant Fossil ◽

Homogeneous Chemical ◽

2D And 3D ◽

2D To 3D

The in situ two-dimensional (2D) and 3D imaging of the chemical speciation of organic fossils is an unsolved problem in paleontology and cultural heritage. Here, we use x-ray Raman scattering (XRS)–based imaging at the carbon K-edge to form 2D and 3D images of the carbon chemistry in two exceptionally preserved specimens, a fossil plant dating back from the Carboniferous and an ancient insect entrapped in 53-million-year-old amber. The 2D XRS imaging of the plant fossil reveals a homogeneous chemical composition with micrometric “pockets” of preservation, likely inherited from its geological history. The 3D XRS imaging of the insect cuticle displays an exceptionally well preserved remaining chemical signature typical of polysaccharides such as chitin around a largely hollowed-out inclusion. Our results open up new perspectives for in situ chemical speciation imaging of fossilized organic materials, with the potential to enhance our understanding of organic specimens and their paleobiology.

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Statistical Assessment of the Microstructure of Barite Aggregate from Different Deposits Using X-Ray Microtomography and Optical Microscopy

Archives of Metallurgy and Materials ◽

10.1515/amm-2017-0104 ◽

2017 ◽

Vol 62 (2) ◽

pp. 697-702

Author(s):

N. Żołek ◽

Z. Ranachowski ◽

P. Ranachowski ◽

D. Jóźwiak-Niedźwiedzka ◽

S. Kudela ◽

...

Keyword(s):

Optical Microscopy ◽

Barium Sulfate ◽

Three Dimensional ◽

Empty Space ◽

Paper Analysis ◽

Micro Ct ◽

Statistical Assessment ◽

Thin Sections ◽

X Ray ◽

Additional Information

AbstractTwo different barite ore (barium sulfate BaSO4) specimens from different localizations were tested and described in this paper. Analysis of the microstructure was performed on polished sections, and on thin sections using X-ray microtomography (micro-CT), and optical microscopy (MO). Microtomography allowed obtaining three-dimensional images of the barite aggregate specimens. In the tomograms, the spatial distribution of the other polluting phases, empty space as well as cracks, pores, and voids – that exceeded ten micrometers of diameter-were possible to visualize. Also, the micro-CT allowed distinguishing between minerals of different density, like SiO2and BaSO4. Images obtained and analyzed on thin sections with various methods using the optical microscopy in transmitted light delivered additional information on the aggregate microstructure, i.e. allow for estimation of the different kinds of inclusions (like the different density of the minerals) in the investigated specimens. Above methods, which were used in the tests, completed each another in order to supply a set of information on inclusions’ distribution and to present the important differences of the barite aggregate specimens microstructure.

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A robust, semi-automated approach for counting cementum increments imaged with X-ray computed tomography

10.1101/2021.03.25.436951 ◽

2021 ◽

Author(s):

Elis Newham ◽

Pamela G Gill ◽

Kate Robson Brown ◽

Neil J Gostling ◽

Ian J Corfe ◽

...

Keyword(s):

Imaging Modality ◽

Human Vision ◽

Laboratory Population ◽

Contrast Imaging ◽

Thin Sections ◽

3D Images ◽

X Ray ◽

Tissue Sections ◽

Tooth Roots ◽

X Ray Computed

Cementum, the tissue attaching mammal tooth roots to the periodontal ligament, grows appositionally throughout life, displaying a series of circum-annual incremental features. These have been studied for decades as a direct record of chronological lifespan. The majority of previous studies on cementum have used traditional thin-section histological methods to image and analyse increments. However, several caveats have been raised in terms of studying cementum increments in thin-sections. Firstly, the limited number of thin-sections and the two-dimensional perspective they impart provide an incomplete interpretation of cementum structure, and studies often struggle or fail to overcome complications in increment patterns that complicate or inhibit increment counting. Increments have been repeatedly shown to both split and coalesce, creating accessory increments that can bias increment counts. Secondly, identification and counting of cementum increments using human vision is subjective, and it has led to inaccurate readings in several experiments studying individuals of known age. Here, we have attempted to optimise a recently introduced imaging modality for cementum imaging; X-ray propagation-based phase-contrast imaging (PPCI). X-ray PPCI was performed for a sample of rhesus macaque ( Macaca mulatta ) lower first molars (n=10) from a laboratory population of known age. A new method for semi-automatic increment counting was then integrated into a purpose-built software package for studying cementum increments. Comparison with data from conventional cementochronology, based on histological examination of tissue sections, confirmed that X-ray PPCI reliably records cementum increments. Validation of the increment counting algorithm suggests that it is robust and provides accurate estimates of increment counts. In summary, we show that our new increment counting method has the potential to overcome caveats of conventional cementochronology approaches, when used to analyse 3D images provided by X-ray PPCI.

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LamNI – an instrument for X-ray scanning microscopy in laminography geometry

Journal of Synchrotron Radiation ◽

10.1107/s1600577520003586 ◽

2020 ◽

Vol 27 (3) ◽

pp. 730-736 ◽

Cited By ~ 1

Author(s):

Mirko Holler ◽

Michal Odstrčil ◽

Manuel Guizar-Sicairos ◽

Maxime Lebugle ◽

Ulrich Frommherz ◽

...

Keyword(s):

High Resolution ◽

Rotation Axis ◽

Optical Methods ◽

Large Area ◽

Thin Sections ◽

3D Images ◽

X Ray ◽

Illumination Direction ◽

Positioning Errors ◽

New Instrument

Across all branches of science, medicine and engineering, high-resolution microscopy is required to understand functionality. Although optical methods have been developed to `defeat' the diffraction limit and produce 3D images, and electrons have proven ever more useful in creating pictures of small objects or thin sections, so far there is no substitute for X-ray microscopy in providing multiscale 3D images of objects with a single instrument and minimal labeling and preparation. A powerful technique proven to continuously access length scales from 10 nm to 10 µm is ptychographic X-ray computed tomography, which, on account of the orthogonality of the tomographic rotation axis to the illuminating beam, still has the limitation of necessitating pillar-shaped samples of small (ca 10 µm) diameter. Large-area planar samples are common in science and engineering, and it is therefore highly desirable to create an X-ray microscope that can examine such samples without the extraction of pillars. Computed laminography, where the axis of rotation is not perpendicular to the illumination direction, solves this problem. This entailed the development of a new instrument, LamNI, dedicated to high-resolution 3D scanning X-ray microscopy via hard X-ray ptychographic laminography. Scanning precision is achieved by a dedicated interferometry scheme and the instrument covers a scan range of 12 mm × 12 mm with a position stability of 2 nm and positioning errors below 5 nm. A new feature of LamNI is a pair of counter-rotating stages carrying the sample and interferometric mirrors, respectively.

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CHANGES IN MICROMORPHOMETRIC PARAMETERS OF VOIDS ALONG THE PROFILE OF ZONAL SOILS IN EUROPEAN RUSSIA

Dokuchaev Soil Bulletin ◽

10.19047/0136-1694-2015-78-42-58 ◽

2015 ◽

pp. 42-58

Author(s):

E. B. Skvortsova ◽

K. N. Abrosimov ◽

K. A. Romanenko

Keyword(s):

Organic Matter ◽

Soil Profile ◽

Pore Space ◽

Organic Matter Content ◽

Soil Mass ◽

Matter Content ◽

European Russia ◽

Vertical Orientation ◽

Thin Sections ◽

Profile Distribution

The soils are distinguished by the presence and the profile distribution pattern of such pedogenic parameters as the organic matter content, available pedofeatures, structural state of the soil mass, etc. They differ in the organization of the pore space throughout the soil profile as well. Under discussion are results of computer micromorphometric analysis of fine macropores d = 0.2-2.0 mm in thin sections of vertical orientation from samples taken in genetic horizons of podzolic, soddy podzolic, gray forest soils and chernozems at the territory of European Russia. The profile changes in voids were analyzed using the most informative morphometric parameters such as the total area of the studied voids in thin sections, the content of fissure-like voids and those of vertical and/or horizontal orientation. The soil types under study showed differences in profile distribution of the above parameters. By analogy with the profile of carbonates, salts, organic matter it is proposed to recognize diagnostic profiles of the pore space represented as a system of voids in genetic horizons of the soil profile. Empiric profiles of the pore space reveal a great diversity. The most complicated organization of the pore space is inherent to soddy podzolic soils, the most simple “smoothed” profiles are characteristic of typical chernozems. The expert qualitative typization showed that the eluvial-illuvial and accumulative-eluvial-illuvial types are dominant among the studied empiric profiles of the pore space (42 and 30% respectively), what is explained by prevailing texture-differentiated soils. On the other hand, it makes possible to use the profile of the pore space as a diagnostic parameter of soils and soil formation processes.

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Comparison of pore space features by thin sections and X-ray microtomography

Applied Radiation and Isotopes ◽

10.1016/j.apradiso.2014.08.003 ◽

2014 ◽

Vol 94 ◽

pp. 182-190 ◽

Cited By ~ 6

Author(s):

H. Alves ◽

I. Lima ◽

J.T. Assis ◽

M. Geraldes ◽

R.T. Lopes

Keyword(s):

Pore Space ◽

Thin Sections ◽

X Ray

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Application of X-Ray Microtomography and Optical Microscopy to Determine the Microstructure of Concrete Penetrated by Carbon Dioxide/ Zastosowanie Mikrotomografii Komputerowej I Mikroskopii Optycznej Do Oceny Mikrostruktury Betonów Poddanych Działaniu Co2

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0245 ◽

2014 ◽

Vol 59 (4) ◽

pp. 1441-1447 ◽

Cited By ~ 3

Author(s):

Z. Ranachowski ◽

D. Józwiak-Niedzwiedzka ◽

P. Ranachowski ◽

F. Rejmund ◽

M. Dabrowski ◽

...

Keyword(s):

Carbon Dioxide ◽

Composite Materials ◽

Optical Microscopy ◽

Material Properties ◽

Three Dimensional ◽

Basic Material ◽

Material Microstructure ◽

Thin Sections ◽

X Ray ◽

Additional Information

Abstract In the paper two advanced methods for testing cement based composites are described and compared. These are X-ray microtomography and optical microscopy. Microtomography supplies three-dimensional images of small concrete specimens. In the tomograms all cracks, pores and other voids and inclusions, that exceed a few micrometers, are shown. Such visualisation can become a valuable tool for analysis of the basic material properties. Images obtained on thin sections and analysed with various methods on optical microscopes supply additional information on material microstructure that cannot be obtained in tomograms. For example it is relatively easy to determine zone penetrated by CO2 ingress. These two methods, presented on examples of tests, complete each another in order to supply a set of information on composition and defects of tested composite materials.

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Microtubule nucleation sequence studied by time-resolved x-ray scattering and electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077402 ◽

1983 ◽

Vol 41 ◽

pp. 766-767

Author(s):

Eva-Maria Mandelkow ◽

Eckhard Mandelkow ◽

Joan Bordas

Keyword(s):

Electron Microscopy ◽

Dynamic Equilibrium ◽

Time Resolved ◽

X Ray ◽

Additional Information ◽

X Ray Scattering ◽

Low Concentrations ◽

Microtubule Growth ◽

Ray Patterns ◽

Ray Scattering

When a solution of microtubule protein is changed from non-polymerising to polymerising conditions (e.g. by temperature jump or mixing with GTP) there is a series of structural transitions preceding microtubule growth. These have been detected by time-resolved X-ray scattering using synchrotron radiation, and they may be classified into pre-nucleation and nucleation events. X-ray patterns are good indicators for the average behavior of the particles in solution, but they are difficult to interpret unless additional information on their structure is available. We therefore studied the assembly process by electron microscopy under conditions approaching those of the X-ray experiment. There are two difficulties in the EM approach: One is that the particles important for assembly are usually small and not very regular and therefore tend to be overlooked. Secondly EM specimens require low concentrations which favor disassembly of the particles one wants to observe since there is a dynamic equilibrium between polymers and subunits.

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3-D reconstruction of molecular shape from microcrystal thin sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077311 ◽

1983 ◽

Vol 41 ◽

pp. 748-749

Author(s):

S. Cusack ◽

J.-C. Jésior

Keyword(s):

Three Dimensional ◽

Molecular Shape ◽

Biological Molecules ◽

Fourier Space ◽

Single Particles ◽

Thin Sections ◽

Standard Methods ◽

X Ray ◽

X Ray Crystallography ◽

Dimensional Reconstruction

Three-dimensional reconstruction techniques using electron microscopy have been principally developed for application to 2-D arrays (i.e. monolayers) of biological molecules and symmetrical single particles (e.g. helical viruses). However many biological molecules that crystallise form multilayered microcrystals which are unsuitable for study by either the standard methods of 3-D reconstruction or, because of their size, by X-ray crystallography. The grid sectioning technique enables a number of different projections of such microcrystals to be obtained in well defined directions (e.g. parallel to crystal axes) and poses the problem of how best these projections can be used to reconstruct the packing and shape of the molecules forming the microcrystal.Given sufficient projections there may be enough information to do a crystallographic reconstruction in Fourier space. We however have considered the situation where only a limited number of projections are available, as for example in the case of catalase platelets where three orthogonal and two diagonal projections have been obtained (Fig. 1).

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