Application of Non-Destructive Methods for the Determination of Microstructural Parameters of Recycled Asphalt Concrete in Track Bed

The extent of the use of asphalt concrete in track bed layers is minimal in contrast to the application of granular materials mostly represented by coarse/fine crushed stone mixture. This article summarizes advantages and disadvantages of the use of asphalt concrete in the track bed construction and provides relevant literature research. The main part of this article focuses on the application of recycled asphalt concrete (so called R-material) in the track bed layer and its following non-destructive X-ray Micro Computed Tomography Method (Micro-CT) for the description of its structural parameters. The contribution of this research is based on the evaluation of the air void and soluble binder content of chosen recycled asphalt concrete. First, it was obtained from laboratory geotechnical models of a railway track, and then from the following implementation in a trial section of an operating railway track. The conclusion contains results of the R-material practical application and findings from Micro-CT.

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Value of micro-CT as an investigative tool for osteochondritis dissecans: A preliminary study with comparison to histology

Acta Radiologica ◽

10.1080/j.1600-0455.2003.00113.x ◽

2003 ◽

Vol 44 (5) ◽

pp. 532-537

Author(s):

A. Mohr ◽

C. Heiss ◽

I. Bergmann ◽

C. Schrader ◽

F. W. Roemer ◽

...

Keyword(s):

Light Microscopy ◽

Osteochondritis Dissecans ◽

Slice Thickness ◽

Micro Ct ◽

Micro Computed Tomography ◽

Entire Sample ◽

Isotropic Resolution ◽

Preliminary Study ◽

Non Destructive ◽

And Cartilage

Purpose: To evaluate micro computed tomography (micro-CT) for the assessment of osteochondritis dissecans in comparison with histology. Material and Methods: Osteochondritis dissecans lesions of 3 patients were evaluated using micro-CT (0.125 mA, 40 keV, 60 μm slice thickness, 60 μm isotropic resolution, entire sample) and light microscopy (toluidine blue, 3–5 μm slice thickness). The methods were compared regarding preparation time, detectability of tissue types and morphologic features of bone and cartilage. Results: Non-destructive micro-CT imaging of the entire sample was faster than histologic preparation of a single slice for light microscopy. Morphologic features of bone and cartilage could be imaged in a comparable way to histology. It was not possible to image cells or different tissue types of bone and cartilage with micro-CT. Conclusion: Micro-CT is a fast, non-destructive tool that may be a supplement or, if detailed histologic information is not necessary, an alternative to light microscopy for the investigation of osteochondritis dissecans.

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When the Utility of Micro-Computed Tomography Collides with Insect Sample Preparation: An Entomologist User Guide to Solve Post-Processing Issues and Achieve Optimal 3D Models

Applied Sciences ◽

10.3390/app12020769 ◽

2022 ◽

Vol 12 (2) ◽

pp. 769

Author(s):

Francesco Simone Mensa ◽

Maurizio Muzzi ◽

Federica Spani ◽

Giuliana Tromba ◽

Christian Dullin ◽

...

Keyword(s):

Critical Point ◽

Light And Electron Microscopy ◽

3D Models ◽

Micro Ct ◽

Micro Computed Tomography ◽

Reconstruction Procedure ◽

Internal Structures ◽

Critical Point Drying ◽

Non Destructive ◽

Preparation Techniques

Many techniques are used today to study insect morphology, including light and electron microscopy. Most of them require to specifically prepare the sample, precluding its use for further investigation. In contrast, micro-CT allows a sample to be studied in a non-destructive and rapid process, even without specific treatments that might hinder the use of rare and hard-to-find species in nature. We used synchrotron radiation (SR) micro-CT and conventional micro-CT to prepare 3D reconstructions of Diptera, Coleoptera, and Hymenoptera species that had been processed with 4 common preparation procedures: critical-point drying, sputter-coating, resin embedding, and air-drying. Our results showed that it is possible to further utilize insect samples prepared with the aforementioned preparation techniques for the creation of 3D models. Specimens dried at the critical point showed the best results, allowing us to faithfully reconstruct both their external surface and their internal structures, while sputter-coated insects were the most troublesome for the 3D reconstruction procedure. Air-dried specimens were suitable for external morphological analyses, while anatomical investigation of soft internal organs was not possible due to their shrinking and collapsing. The sample included in resin allowed us to reconstruct and appreciate the external cuticle and the internal parts. In this work, we demonstrate that insect samples destined to different analyses can be used for new micro-CT studies, further deepening the possibility of state-of-the-art morphological analyses.

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Micro-CT for Biological and Biomedical Studies: A Comparison of Imaging Techniques

Journal of Imaging ◽

10.3390/jimaging7090172 ◽

2021 ◽

Vol 7 (9) ◽

pp. 172

Author(s):

Kleoniki Keklikoglou ◽

Christos Arvanitidis ◽

Georgios Chatzigeorgiou ◽

Eva Chatzinikolaou ◽

Efstratios Karagiannidis ◽

...

Keyword(s):

Laser Scanning ◽

Imaging Techniques ◽

Laser Scanning Microscopy ◽

Three Dimensions ◽

Morphological Data ◽

Confocal Laser ◽

Micro Ct ◽

Micro Computed Tomography ◽

Non Destructive ◽

Great Resolution

Several imaging techniques are used in biological and biomedical studies. Micro-computed tomography (micro-CT) is a non-destructive imaging technique that allows the rapid digitisation of internal and external structures of a sample in three dimensions and with great resolution. In this review, the strengths and weaknesses of some common imaging techniques applied in biological and biomedical fields, such as optical microscopy, confocal laser scanning microscopy, and scanning electron microscopy, are presented and compared with the micro-CT technique through five use cases. Finally, the ability of micro-CT to create non-destructively 3D anatomical and morphological data in sub-micron resolution and the necessity to develop complementary methods with other imaging techniques, in order to overcome limitations caused by each technique, is emphasised.

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Defect Detection of Metal Injection Modeling by Micro Computed Tomography

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.229-231.1445 ◽

2012 ◽

Vol 229-231 ◽

pp. 1445-1448

Author(s):

Wei Yun Huang ◽

Chang Da Chen ◽

Yen Nien Chen ◽

Wei Jen Shih ◽

Chih Han Chang

Keyword(s):

Computed Tomography ◽

Injection Molding ◽

Hot Isostatic Pressing ◽

Cost Effective ◽

High Volume ◽

Metal Injection Molding ◽

Micro Ct ◽

Micro Computed Tomography ◽

Destructive Testing ◽

Non Destructive

Metal injection molding (MIM) is a combination of metal powder and injection molding technology. The main advantage of this technology for material parts with small and complex shape is to manufacture cost-effective and high-volume products. The main processing steps include mixing, injection molding, debinding , sintering, and hot isostatic pressing (HIP) in order to reduce internal porosity of metals, then to improve mechanical properties. This study is based on non-destructive testing method to determine the possible defect inside the internal structure of the MIM parts. Three types of parts with and without HIP were evaluated investigated in this study. The micro computed tomography (Micro-CT) is used to scan these parts. Based the reconstructed section images from CT, the defects can be identified. It showed that with HIP the much of detects could be reduced. To conclude, Micro CT could be used to detect, in a non-destructive way, the internal detect within MIM parts can be found out in the micro-CT images, so that the manufacturing process could be modified to improve the quality of MIM parts.

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Micro-computed tomography for natural history specimens: a handbook of best practice protocols

European Journal of Taxonomy ◽

10.5852/ejt.2019.522 ◽

2019 ◽

Author(s):

Kleoniki Keklikoglou ◽

Sarah Faulwetter ◽

Eva Chatzinikolaou ◽

Patricia Wils ◽

Jonathan Brecko ◽

...

Keyword(s):

Computed Tomography ◽

Natural History ◽

Best Practice ◽

Ct Imaging ◽

Three Dimensions ◽

X Rays ◽

Micro Ct ◽

Micro Computed Tomography ◽

Ct Technology ◽

Non Destructive

Micro-computed tomography (micro-CT or microtomography) is a non-destructive imaging technique using X-rays which allows the digitisation of an object in three dimensions. The ability of micro-CT imaging to visualise both internal and external features of an object, without destroying the specimen, makes the technique ideal for the digitisation of valuable natural history collections. This handbook serves as a comprehensive guide to laboratory micro-CT imaging of different types of natural history specimens, including zoological, botanical, palaeontological and geological samples. The basic principles of the micro-CT technology are presented, as well as protocols, tips and tricks and use cases for each type of natural history specimen. Finally, data management protocols and a comprehensive list of institutions with micro-CT facilities, micro-CT manufacturers and relative software are included.

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Use of Micro-Computed Tomography for Dental Studies in Modern and Fossil Odontocetes: Potential Applications and Limitations

NAMMCO Scientific Publications ◽

10.7557/3.2616 ◽

2013 ◽

Vol 8 ◽

Cited By ~ 2

Author(s):

Carolina Loch ◽

Donald R Schwass ◽

Jules A Kieser ◽

R Ewan Fordyce

Keyword(s):

Computed Tomography ◽

Feeding Habits ◽

Good Resolution ◽

X Rays ◽

Micro Ct ◽

Micro Computed Tomography ◽

Pulp Cavity ◽

Diagenetic Alteration ◽

Extant Species ◽

Non Destructive

Teeth are important elements in studies of modern and fossil Cetacea (whales, dolphins), providing information on feeding habits, estimations of age and phylogenetic relationships. The growth layer groups (GLGs) recorded in dentine have demonstrated application for aging studies, but also have the potential to elucidate life history phenomena such as metabolic or physiologic events. Micro-Computed Tomography (Micro-CT) is a non-invasive and non-destructive technique that allows 3-dimensional study of mineralized tissues, such as human teeth, and their physical properties. Teeth from extant dolphins (Cetacea: Odontoceti) and some fossil odontocetes were scanned in a Skyscan 1172 Micro-CT desktop system. X-rays were generated at 100 kV and 100 µA for extant samples, and at 80kV and 124 µA for fossils. 0.5 mm thick aluminum and copper filters were used in the beam. Reconstructed images were informative for most extant species, showing a good resolution of the enamel layer, dentine and pulp cavity. Greyscale changes in the dentinal layers were not resolved enough to show GLGs. Visualization of the internal structure in fossil cetacean teeth depended on the degree of diagenetic alteration in the specimen; undifferentiated enamel and dentine regions probably reflect secondary mineralization. However, internal details were finely resolved for one fossil specimen, showing the enamel, internal layers of dentine and the pulp cavity. Micro-CT has been proven to be a useful tool for resolving the internal morphology of fossil and extant teeth of cetaceans before they are sectioned for other morphological analyses; however some methodological refinements are still necessary to allow better resolution of dentine for potential application in non-destructive age determination studies.

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Applying micro-computed tomography for porosity analysis of polypropylene modified with microspheres

MATEC Web of Conferences ◽

10.1051/matecconf/202133201017 ◽

2021 ◽

Vol 332 ◽

pp. 01017

Author(s):

Piotr Szewczykowski

Keyword(s):

Computed Tomography ◽

Solid Material ◽

Micro Ct ◽

Micro Computed Tomography ◽

Material Density ◽

X Ray ◽

Blowing Agent ◽

Central Measuring ◽

Porosity Analysis ◽

Non Destructive

Porosity of polypropylene samples was investigated by applying X-ray micro-computed tomography (micro-CT), which is getting more and more popular as a non-destructive method. Microspheres were applied as a blowing agent at three concentrations: 3%, 6% and 9% by weight. Tensile testing specimens were obtained by injection molding technology and its central, measuring part were examined by micro – CT. Results were compared to porosity calculated based on difference in porous and solid material density. Pore size distribution curves were discussed as well.

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Classical and new bioerosion trace fossils in Cretaceous belemnite guards characterised via micro-CT

Fossil Record ◽

10.5194/fr-20-173-2017 ◽

2017 ◽

Vol 20 (2) ◽

pp. 173-199 ◽

Cited By ~ 9

Author(s):

Max Wisshak ◽

Jürgen Titschack ◽

Wolf-Achim Kahl ◽

Peter Girod

Keyword(s):

Three Dimensional ◽

Trace Fossils ◽

Added Value ◽

Type Material ◽

Micro Ct ◽

Micro Computed Tomography ◽

Type Specimens ◽

Present Contribution ◽

Morphometric Analyses ◽

Non Destructive

Abstract. The ongoing technical revolution in non-destructive 3-D visualisation via micro-computed tomography (micro-CT) finds a valuable application in the studies of bioerosion trace fossils, since their three-dimensional architecture is hidden within hard substrates. This technique, in concert with advanced segmentation algorithms, allows a detailed visualisation and targeted morphometric analyses even of those bioerosion traces that are otherwise inaccessible to the widely applied cast-embedding technique, because they either are filled with lithified sediment or cement or are preserved in inherently insoluble or silicified host substrates, or because they are established type material and should not be altered. In the present contribution selected examples of such cases are illustrated by reference to bioerosion trace fossils preserved in Late Cretaceous belemnite guards from the European Chalk Province. These case studies comprise an analysis of a diverse ichno-assemblage found associated with the lectotype of the microboring Dendrina dendrina (Morris, 1851) in a belemnite from the upper Campanian to lower Maastrichtian chalk of Norfolk, England, and the description of two new bioerosion trace fossils with type specimens found in belemnite guards from the lower Campanian limestones of Höver, Germany. The latter are Lapispecus hastatus isp. n., a tubular and occasionally branched macroboring for which a sipunculan or a phoronid trace maker are discussed, and Entobia colaria isp. n., a camerate network formed by an excavating sponge that eroded diagnostic grated apertures at the locations of the presumed inhalant papillae or exhaling pores, adding to or replacing filtering devices that are otherwise made of tissue and spicules. As an added value to the non-destructive visualisation procedure, the processed X-ray micro-CT scans of the studied type material provide 3-D models that may now serve as digitypes that can be studied as digital facsimile without the necessity of consulting the actual type specimens.

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Automated segmentation and description of the internal morphology of human permanent teeth by means of micro-CT

BMC Oral Health ◽

10.1186/s12903-021-01551-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

David Haberthür ◽

Ruslan Hlushchuk ◽

Thomas Gerhard Wolf

Keyword(s):

High Resolution ◽

Permanent Teeth ◽

Apical Region ◽

Automated Segmentation ◽

Micro Ct ◽

Ct Scanner ◽

Micro Computed Tomography ◽

Human Teeth ◽

Internal Morphology ◽

Non Destructive

AbstractHigh-resolution micro-computed tomography is a powerful tool to analyze and visualize the internal morphology of human permanent teeth. It is increasingly used for investigation of epidemiological questions to provide the dentist with the necessary information required for successful endodontic treatment. The aim of the present paper was to propose an image processing method to automate parts of the work needed to fully describe the internal morphology of human permanent teeth. One hundred and four human teeth were scanned on a high-resolution micro-CT scanner using an automatic specimen changer. Python code in a Jupyter notebook was used to verify and process the scans, prepare the datasets for description of the internal morphology and to measure the apical region of the tooth. The presented method offers an easy, non-destructive, rapid and efficient approach to scan, check and preview tomographic datasets of a large number of teeth. It is a helpful tool for the detailed description and characterization of the internal morphology of human permanent teeth using automated segmentation by means of micro-CT with full reproducibility and high standardization.

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Characterization of Coloured Gemstones by X-ray Micro Computed Tomography

Minerals ◽

10.3390/min11020178 ◽

2021 ◽

Vol 11 (2) ◽

pp. 178

Author(s):

René Heyn ◽

Abraham Rozendaal ◽

Anton Du Plessis ◽

Carene Mouton

Keyword(s):

Computed Tomography ◽

Low Cost ◽

Micro Ct ◽

Fracture Detection ◽

Micro Computed Tomography ◽

X Ray ◽

Complementary Method ◽

Color Changes ◽

Non Destructive

The monetary value of gemstones is based on five variables: rarity, cut, weight, color and clarity. The latter refers to internal impurities and defects. Fashion may also dictate demand and price. To enhance some of these features and value, gemstones are treated. Disclosure or nondisclosure thereof has been controversial and affected consumer confidence. Most of these treatments are difficult to detect with the naked eye and accurately quantify with traditional optical and analytical methods. X-ray micro computed tomography (micro-CT or μCT) is proposed as a relatively low cost, physically non-destructive and complementary method to detect and quantify clarity enhancement and also to provide a unique 3D fingerprint of each gemstone. A collection of 14 cut colored gemstones was selected. Micro-CT scans allowed fracture detection, their distribution and calculation of filler volume as well as 3D mapping of inclusions, surface and internal imperfections and artificially induced modifications. As a result the method allows the construction of a digital twin. X-ray exposure could however induce unwanted color changes. This effect was minimized or eliminated by optimizing dosage and exposure time.

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