High-resolution X-ray Micro-computed Tomography Research Articles

Characterisation of pore structure of bulk wheat mixed with dockage using X-ray micro-computed tomography and deep learning

Characterisation of pore structure inside grain bulks is essential for predicting the airflow resistance during grain drying and aeration. Herein, the 3D pore network of wheat mixed with different percentages of canola and dockage was characterised. The characterised parameters include pore size, throat length, coordination number, airpath length, and tortuosity. To simulate the grain storage condition, the loaded wheat mixtures were cured using wax at 110 °C. The images of the waxed wheat mixtures were produced by using a high-resolution X-ray micro-computed tomography (μCT) system at a resolution of 50 μm per pixel. The computed space distribution was based on the 3D medial axis analysis of each image stack using Dragonfly 4.1 software. The pore space was segmented using a deep-learning model with 90.1–98.0% accuracy. A watershed-based image algorithm was used to generate the pore network from the segmented pore space. The pore structure parameters were extracted from the pore network of each wheat mixture. Most pores were classified as mesopores (>99%) in a range from 62.5 to 4000 μm, with less than 1% classified as micropores (1–62.5 μm). The mean pore size of clean bulk wheat was 648 ± 403 μm with a mean throat length of 1115 ± 611 μm. In the mixtures with 10% canola, 5 and 10% wheat dockage, the mean pore size was reduced by 10%, 29%, and 17%, respectively, from clean wheat. Adding canola and dockage generally influenced the connectivity in the pore microstructure with changes in bulk porosity, tortuosity, airpath number, and length.

Using X-ray computed tomography and pore-scale numerical modeling to study the role of heterogeneous rock surface wettability on hydrogen-brine two-phase flow in underground hydrogen storage

Underground hydrogen storage (UHS) is receiving increasing attention to address the challenges in hydrogen storage. A crucial aspect of UHS is understanding the transport of hydrogen in subsurface porous media. In this work, hydrogen core flooding experiments were conducted in a sandstone sample and then the pore-scale distribution of hydrogen and brine was visualized using high-resolution X-ray micro-computed tomography (micro-CT). After CT image processing, we measured the surface contact angles (CAs) on rock surfaces and found that the measured CAs followed a log-normal distribution. To investigate the influence of rock surface wettability on the transport properties in the hydrogen-brine-sandstone system, the lattice Boltzmann (LB) method was used to simulate two-phase flows with different surface CA distributions; hydrogen-brine relative permeability and capillary pressure curves through the primary drainage, imbibition, and secondary drainage processes were obtained by LB simulations. X-ray CT scanning showed that hydrogen resided in both large pores and small pores and pore throats after the primary drainage process (i.e., hydrogen displacing brine), whereas after the imbibition process (i.e., brine displacing hydrogen) hydrogen stayed primarily in large pores where the capillary pressure barriers were low. The LB two-phase flow modeling illustrated that water’s relative permeability increased whereas hydrogen’s relative permeability decreased when the core flooding moved from primary drainage to imbibition; in contrast, when the core flooding moved from imbibition to secondary drainage, water’s relative permeability decreased whereas hydrogen’s relative permeability increased. Decreasing the surface CA increased the capillary pressure and reduced the hydrogen residual rate, which indicates high hydrogen retrievability and thus is favorable for UHS practice. The change in CA’s standard deviation did not cause noticeable changes in water’s relative permeability curves, whereas it resulted in noticeable changes in hydrogen’s relative permeability curves. This work is the first study that utilizes X-ray micro-CT scanning and pore-scale multiphase flow modeling to quantitatively and comprehensively investigate hydrogen-brine two-phase flow properties under different rock surface wettability distributions. The research findings from this study will advance the understanding of hydrogen transport in an underground storage system and provide essential data for large-scale field studies in UHS.

Low-velocity impact responses of UHMWPE fiber/epoxy laminates with plasma treatment and polypyrrole grafting

The physical–chemical method with plasma treatment and polypyrrole grafting was used to improve the low velocity impact resistance of the ultra-high molecular weight polyethylene (UHMWPE) fiber/epoxy laminates. The experimental impact force–time curves and impact force-central displacement curves were recorded. The microscopic void distribution of impact region was quantitatively counted by high-resolution X-ray micro-computed tomography (μCT). Then the residual compressive strengths for the laminates after low velocity impact were explored. Experimental results showed that the impact resistance and residual strength of the laminates treated by the combined plasma treatment and polypyrrole grafting were significantly improved by comparing with the plasma treatment alone, and the void fraction also reduced remarkably. In addition, the impact resistance with single physical plasma treatment method was more affected by the mixture ratio of nitrogen and oxygen.

Xylem-dwelling pathogen unaffected by local xylem vessel network properties in grapevines (Vitis spp.).

Xylella fastidiosa (Xf) is the xylem-dwelling bacterium associated with Pierce's disease (PD), which causes mortality in agriculturally important species, such as grapevine (Vitis vinifera). The development of PD symptoms in grapevines depends on the ability of Xf to produce cell-wall-degrading enzymes to break up intervessel pit membranes and systematically spread through the xylem vessel network. Our objective here was to investigate whether PD resistance could be mechanistically linked to xylem vessel network local connectivity. We used high-resolution X-ray micro-computed tomography (microCT) imaging to identify and describe the type, area and spatial distribution of intervessel connections for six different grapevine genotypes from three genetic backgrounds, with varying resistance to PD (four PD resistant and two PD susceptible). Our results suggest that PD resistance is unlikely to derive from local xylem network connectivity. The intervessel pit area (Ai) varied from 0.07 ± 0.01 mm2 mm-3 in Lenoir to 0.17 ± 0.03 mm2 mm-3 in Blanc do Bois, both PD resistant. Intervessel contact fraction (Cp) was not statically significant, but the two PD-susceptible genotypes, Syrah (0.056 ± 0.015) and Chardonnay (0.041 ± 0.013), were among the most highly connected vessel networks. Neither Ai nor Cp explained differences in PD resistance among the six genotypes. Bayesian re-analysis of our data shows moderate evidence against the effects of the traits analysed: Ai (BF01 = 4.88), mean vessel density (4.86), relay diameter (4.30), relay density (3.31) and solitary vessel proportion (3.19). Our results show that radial and tangential xylem network connectivity is highly conserved within the six different Vitis genotypes we sampled. The way that Xf traverses the vessel network may limit the importance of local network properties to its spread and may confer greater importance on host biochemical responses.

3D visualization of oil-abundant limon flavedo layer under drying

This study investigated the transformations of lemon flavedo tissues during freeze-drying based on high-resolution X-ray micro-computed tomography (μ-CT) and confocal laser scanning microscopy (CLSM). Contrast-enhanced segmentation, traversal statistic algorithmic analysis, and 3D visualization of lemon peel texture are studied. To avoid pseudo-imaging caused by precipitation of contrast enhancer, low concentration cesium iodide was used to improve X-ray contrast and decrease enlarged inter-cellular region. X-ray μ-CT showed the precipitation of contrast enhancers at the intercellular boundary after freeze-drying. The grayscale thresholding method was presented as the most suitable segmentation method for detecting cell walls due to the high noise level caused by low contrast enhancer concentration in the reconstructed images. The faster water loss at the primary drying stage caused the disintegration of oil glands and induced high porosity of 0.7 % in fresh to 0.84 % in 0.5 h freeze-dried. The results suggest that noise filtering based on voxel statistics provides an efficient approach for the inter and intra-cellular microstructural analysis of excessively watery plant tissues with low contrast enhancer concentration.

Clustering characteristics of Fe-rich intermetallics in high vacuum die cast AlSiMgMn alloys with high resolution μ-CT inspection

The AlSiMgMn alloys with different Fe and Mn contents were prepared with high vacuum die casting (HVDC) process. The Fe-rich intermetallics in the surface layer and center of the alloys were inspected with high-resolution 3D X-ray micro-computed tomography (μ-CT), and the growth mechanism of the primary Fe-rich phase was analyzed through their different 3D morphographies. By combining Bisecting K-means and DBSCAN (Density-Based Spatial Clustering of Applications with Noise) methods, the intermetallic clusters in the surface layer and center were quantified. The results show that the primary Fe-rich intermetallics were characterized as hexahedron and octagonal dendrite shapes with large size while the eutectic Fe-rich intermetallics were polyhedron and Chinese-script shapes. When Fe and Mn contents of the alloys were lower, the intermetallic clusters in the surface layer were with less cluster number and larger intermetallic distances showing uniform distribution whereas the clusters in the center were more and had shorter distances. In the case of alloys with higher Fe and Mn contents, the intermetallics showed clustering distribution in both the surface layer and center. The mechanism for the intermetallic cluster formation in the surface layer and center was further discussed.

In situ X-ray tomography of fracture behaviour in low-porosity L-PBF AlSi10Mg alloy with laser shock peening

ABSTRACT In this study, we employed a novel hybrid AM process, in which periodic laser shock peening (LSP) treatments were added to the standard laser powder bed fusion (L-PBF) process, for fabricating the AlSi10Mg alloy. As a result, the porosity of the alloy was reduced by approximately 90%. To monitor damage evolution, we conducted in situ tensile tests using high-resolution synchrotron radiation X-ray micro-computed tomography. The results indicate that in the LSP-treated L-PBF AlSi10Mg alloy, with a porosity of around 0.05%, the plasticity of vertical tensile samples significantly increases, and the fracture strain closely resembles that of the horizontal sample. The reduction in porosity results in increased spacing between adjacent defects, which decreases the interaction between defects. Consequently, the rapid fracture caused by the merge of large defects is prevented. Notably, micro-cracks observed in the vertical samples before tensile fracture primarily originates at the molten pool boundaries rather than from defects.

Generating three-dimensional bioinspired microstructures using transformer-based generative adversarial network

Biomaterials possess extraordinary properties due to intricate structures on the microscale. Learning from these microstructures is critical for the design of high-performance materials with multiple functions. However, explicit modeling of the microstructures is not always feasible. This study developed a deep generative network with a self-attention mechanism to generate three-dimensional (3D) bioinspired microstructures. The robustness of the model was first checked by generating a series of gyroids, a mathematically well-defined microstructure, which showed excellent consistency with the desired structures. The model was then applied to the microstructure of the elk antlers, which are complex and cannot be directly expressed mathematically. The results showed that the model also performs well in complex, ill-defined biological materials. The model learned the inherent patterns, generating different structures with similar geometric features. This study demonstrates the potential of using Transformer-based deep generative models that can be used to generate novel 3D microstructures from limited high-resolution X-ray micro-computed tomography data.

Bamboo as a substitute for plastic: Underlying mechanisms of flexible deformation and flexural toughness of bamboo at multiple scales

To develop bamboo-based products by weaving, winding and molding for promoting "bamboo as a substitute for plastic", it is urgent to fully understand the underlying mechanisms of flexible deformation and flexural toughness of bamboo at multiple scales. In this study, we quantified the micro deformation and strain of bamboo cells at different curvatures by in situ high-resolution field emission scanning electron microscopy (FE-SEM) and X-ray micro-computed tomography (Micro-CT) to analyze its flexible deformation at cellular and nano scales. The toughening mechanism embodied in fracture morphology was quantitatively calculated using mathematical models at macro and cell-wall scales. Results showed that bamboo possessed both excellent flexible deformation and flexural toughness in the longitudinal direction with the variation of fiber contents in the radial direction of bamboo culm. Flexible deformation of bamboo was achieved through synergistic cellular deformation between tensile sclerenchyma fibers (SFs) and compressible parenchyma cells (PCs) adapted to external stress distribution. SFs with greater tensile strain (0.027) bore the load even after the PCs broke (0.019), while the PCs in the compression layer acted as a buffer through plastic deformation. Meanwhile, the cell-wall sublayer wound by microfibrils at different angles, demonstrated significantly different Young's modulus and fracture modes verified by a mathematical model. Multiwalled fiber pullout and crack deflection were the main toughening mechanisms in bamboo at macro- and cellular scales. Multiwalled fibers pullout energy contributed the most to fracture energy dissipation, accounting for 46.0∼77.5%, whereas the weak intercellular interface effectively promoted crack deflection, reduced the local stress and delayed bamboo failure.

Skeletal effects following developmental flame-retardant exposure are specific to sex and chemical class in the adult Wistar rat.

Introduction: Accumulating evidence reveals that endocrine disrupting chemicals (EDCs) can disrupt aspects of metabolic programming, suggesting that skeletal development may be at risk, a possibility that is rarely examined. The commercial flame retardant (FR) mixture, Firemaster 550 (FM 550), has repeatedly been shown to negatively influence metabolic programming, raising concerns that skeletal integrity may consequently be impaired. We have previously shown that gestational and lactational exposure to 1,000µg FM 550 negatively affected sex-specific skeletal traits in male, but not female, rats assessed at 6months of age. Whether this outcome is primarily driven by the brominated (BFR) or organophosphate ester (OPFR) portions of the mixture or the effects persist to older ages is unknown. Materials and methods: To address this, in the present study, dams were orally exposed throughout gestation and lactation to either 1,000μg BFR, 1,000µg OPFR, or 2,000µg FM 550. Offspring (n = 8/sex/exposure) were weaned at PND 21 and assessed for femoral cortical and trabecular bone parameters at 8months of age by high-resolution X-ray micro-computed tomography (micro-CT). Serum levels of serotonin, osteocalcin, alkaline phosphatase, and calcium were quantified. Results: FM 550 affected both sexes, but the females were more appreciably impacted by the OPFRs, while the males were more vulnerable to the BFRs. Conclusion: Although sex specificity was expected due to the sexual dimorphic nature of skeletal physiology, the mechanisms accounting for the male- and female-specific phenotypes remain to be determined. Future work aims to clarify these unresolved issues.

An investigation of mineral floatability versus mineral surface exposure and hydrophobicity by high-resolution X-ray microcomputed tomography, film flotation, contact angles, and modeling

Determination of mineral floatability versus mineral surface exposure and hydrophobicity has been challenging because of significant deviations of flotation model assumptions for real mineral surfaces and the unavailability of suitable research tools. Here, we report a successful application of combined advanced experimental techniques and modeling to determine mineral floatability versus mineral surface exposure and hydrophobicity. Specifically, high-resolution X-ray microcomputed tomography (HRXMT) was used to determine the surface exposure of composite mineral particles of quartz and chalcopyrite and compared it with the mineral floatability obtained by film flotation experiments and the contact angle (CA) of the mineral particles. The surface exposure was obtained from the HRXMT images using in-house software. Cassie's theory was applied to estimate the CA of composite particles from the CAs on single mineral phases. The mineral floatability was described by extending the new theory on max adhesion force (tenacity) that holds the particles attached to the bubble surface. The comparison shows a good agreement between the tenacity, surface tension, and the CA calculated from the surface exposure data together with the CA on single mineral phases. This is the first work that quantifies the effect of surface exposure on the floatability of composite particles and can be applied to predict the flotation performance of the composite particles in the mineral processing industry.

A new Carboniferous edaphosaurid and the origin of herbivory in mammal forerunners

Herbivory evolved independently in several tetrapod lineages during the Late Carboniferous and became more widespread throughout the Permian Period, eventually leading to the basic structure of modern terrestrial ecosystems. Here we report a new taxon of edaphosaurid synapsid based on two fossils recovered from the Moscovian-age cannel coal of Linton, Ohio, which we interpret as an omnivore–low-fibre herbivore. Melanedaphodon hovaneci gen. et sp. nov. provides the earliest record of an edaphosaurid to date and is one of the oldest known synapsids. Using high-resolution X-ray micro-computed tomography, we provide a comprehensive description of the new taxon that reveals similarities between Late Carboniferous and early Permian (Cisuralian) members of Edaphosauridae. The presence of large bulbous, cusped, marginal teeth alongside a moderately-developed palatal battery, distinguishes Melanedaphodon from all other known species of Edaphosauridae and suggests adaptations for processing tough plant material already appeared among the earliest synapsids. Furthermore, we propose that durophagy may have provided an early pathway to exploit plant resources in terrestrial ecosystems.

Microscopic void distribution of 3D printed polymer composites with different printing direction

The microscopic void distribution of 3D printed short fiber reinforced polymer composites with different printing direction was studied in this paper. The internal voids including the independent voids and connected voids were quantitatively counted by high-resolution X-ray micro-computed tomography (μCT) method. After the CT scan, the specimens were subjected to compression tests. Experimental results showed that the void volume of the specimens with the 0° printing direction was much higher than that with 45°/−45° and 0°/90° printing directions, and the connected voids were dominant. By comparison, the out-of-plane compressive resistance of 0° printed specimen was lower than that of the other two printing directions because of higher proportion of internal voids.

Using Digital Rock Physics to Evaluate Novel Percussion Core Quality

This paper details a benchmarking and validation workflow using digital rock physics (DRP) to evaluate the effectiveness of various percussion sidewall core (PSWC) acquisition methods. The workflow consists of obtaining digital rock properties and images of reference material to compare with material obtained from laboratory percussion sidewall acquisition, including novel designs. This workflow allows insight into the acquisition processes and potential sources of damage in the PSWC technique, and potentially other rock sampling techniques, and offers an opportunity to evaluate its appropriateness as a subsurface rock sample acquisition method. Sample cubes from six outcrop sandstone formations of known properties were used in the testing program to cover a wide range of particularly low and medium unconfined compressive strengths (UCS). Multiple control rotary plug samples were cut from each sandstone formation. The sample cubes were then used as the parent material in laboratory testing of various designs of PSWC bullets. The PSWC bullets, including novel designs, were shot in simulated downhole environments. Both control rotary plug samples and PSWC test core samples were imaged with high-resolution X-ray micro-computed tomography (micro-CT) at resolutions between 2 and 11 μm, and digital rock analysis was conducted on all samples. Using pre- and post-test images, the damage could be identified, and petrophysical properties, including porosity and permeability, could be determined and directly compared with DRP results from control samples and available routine core analysis (RCA) results. DRP provides unique insight to evaluate and quantify changes (or lack of changes) to the sample material subjected to the PSWC acquisition. Damage encountered in the test samples includes grain crushing and compaction that degrades storage and transport properties and dilatant zones that locally enhance transport properties. The presence, frequency, and distribution of these zones are dependent on experimental parameters. In all cases, undisturbed rock fabric could be identified in each sample, and intact texture was verified by comparison with reference material. A novel and efficient method for acquiring and evaluating subsurface samples was developed and benchmarked. Lab results indicate this method may be equally applicable to low- and mid-range UCS rocks. This approach enables a cost-effective reservoir characterization strategy. By optimizing PSWC bullet design and coupling this with mature, image-based digital rock technology, this work demonstrated that the samples and results obtained by this method are representative and that the controls on storage and transport properties are well understood.

Lattice Boltzmann simulation of liquid water transport in gas diffusion layers of proton exchange membrane fuel cells: Impact of gas diffusion layer and microporous layer degradation on effective transport properties

Polymer Electrolyte Membrane Fuel Cells (PEMFCs) represent a promising technology for clean drivetrain solutions, in particular for heavy-duty applications. However, lifetime requirements demand high durability of each cell component.In this work, transport of liquid water through pristine and degraded gas diffusion layers (GDL) was simulated with a 3D Color-Gradient Lattice Boltzmann model. The GDL microstructure was reconstructed from high-resolution X-ray micro-computed tomography (μ-CT) of an impregnated Freudenberg H14. The effect of a microporous layer (MPL) was considered by reconstruction of an impregnated and MPL-coated H14. Aged microstructures were generated artificially, assuming loss of polytetrafluoroethylene (PTFE) within the GDL and increase of MPL macroporosity as main degradation mechanisms. Liquid water transport within aged microstructures was simulated by imposing a liquid phase flow rate until breakthrough was reached. Subsequently, the GDL microstructures were analyzed for their breakthrough characteristics by means of saturation and effective gas transport properties. When the MPL was pristine, no distinct GDL degradation effect was observable, this was attributed to the MPL dominating capillary transport. MPL aging, however, led to increased saturations and thus to a deterioration of the effective gas transport. With a partially degraded MPL, aging of the GDL then appeared to affect the breakthrough characteristics.

Osteology of the caecilian Gegeneophis carnosus (Beddome, 1870) (Amphibia: Gymnophiona: Grandisoniidae) from the Western Ghats of peninsular India

Abstract The osteology of the poorly known grandisoniid caecilian Gegeneophis carnosus is described for the first time by applying high-resolution X-ray micro-computed tomography to some recently collected material. The ossified skeleton comprises a stegokrotaphic skull, lower jaw, and vertebral column. The braincase, composed of the sphenethmoid and os basale, is covered by eight other cranial elements viz. nasopremaxilla, frontal, parietal, squamosal, pterygoquadrate, maxillopalatine, vomer, and stapes. The eye is covered by the maxillopalatine, and an (open) orbit is absent. The sphenethmoid is not exposed and lacks a solum nasi or a ventral flange. The olfactory chamber lacks an olfactory eminence. Slight asymmetries were observed in the structure and/or size of the left and right frontals and parietals and in the number and size of some foramina. Except for pterygoquadrate and stapes, all bones are pierced by foramina for nerves and/or blood vessels. The lower jaw shows a typical caecilian pattern with dentigerous pseudodentary and edentulous pseudoangular. Numbers of vertebrae range from 123–130 (mean 126). The vertebrae are somewhat heterogenous, varying in size and proportions along the column. Comparisons are made with other caecilians, especially other grandisoniids. Aspects of the cranial osteology of Gegeneophis, such as the closed orbit, subterminal mouth, and stegokrotaphy are possible adaptations to dedicated fossoriality, but functional, behavioural, and field ecological data are not yet available to test this.

Growth mechanisms of composite fouling: The impact of substrates on detachment processes

Fouling processes present significant challenges in many industries; understanding these processes is crucial for accurate prediction and planning effective mitigation protocols. Composite fouling is prevalent in many industrial applications, however, studies of these systems are scarce. We present, for the first time, new insights on the interaction between two common crystallization foulants: BaSO4 and CaCO3. We conducted a series of crystal growth experiments in a plug flow reactor. We used high resolution X-ray micro-computed tomography to visualize the crystal formation. In the first set of experiments, crystals (either BaSO4 or CaCO3) were grown on pristine steel surfaces; these pre-fouled surfaces were then used as substrates for the composite fouling studies. The chemical compositions of the substrates were different from that of the foulant, i.e., either BaSO4 on CaCO3 or CaCO3 on BaSO4. Growth rates were obtained through gravimetric analysis. We characterized surface properties, such as the crystal size distribution, surface coverage, and texture parameters through advanced image analysis. Our results reveal that deposition behaviour depends on complex substrate-foulant interactions. Whereas the net deposition of CaCO3 on a BaSO4 substrate increased with time, significant detachment processes were observed for the reverse case. The increased detachment of BaSO4 on a CaCO3 substrate can be attributed to either the weak interaction within the CaCO3 crystal structure or the CaCO3/steel interface. We also show how substrate properties govern crystal cluster sizes and distribution. The results from this work provide a basis for the development of more comprehensive prediction models.

Lattice Boltzmann simulation of liquid water transport in gas diffusion layers of proton exchange membrane fuel cells: Parametric studies on capillary hysteresis

Water management is crucial for reliable operation of Polymer Electrolyte Membrane Fuel Cells (PEMFC). Here, the gas diffusion layer (GDL) plays an essential role as it has to ensure efficient water removal from and oxygen transport to the catalyst layer.In this study water transport through porous carbon felt GDLs was simulated using a 3D Color-Gradient Lattice Boltzmann model. Simulations were carried out on microstructures of plain and impregnated fiber substrates of a Freudenberg H14. The GDL microstructures were reconstructed from high-resolution X-ray micro-computed tomography (μ-CT). For the distinction of carbon fibers and polytetrafluoroethylene (PTFE) in the binarized microstructures an in-house algorithm was developed. The additive was specified heterogeneously in the GDL through-plane direction employing a PTFE loading profile as derived based on μ-CT image data. In the in-plane direction the additive was furthermore defined in a realistic fashion near carbon fiber intersections. Prior to parametric studies on capillary behavior a sophisticated modeling approach for semipermeable membranes had to be developed to account for experimental boundary conditions. Capillary hysteresis was then investigated by simulation of intrusion and drainage curves and subsequent comparison to testbench data.

How Do Roots Interact with Layered Soils?

Vegetation alters soil fabric by providing biological reinforcement and enhancing the overall mechanical behaviour of slopes, thereby controlling shallow mass movement. To predict the behaviour of vegetated slopes, parameters representing the root system structure, such as root distribution, length, orientation and diameter, should be considered in slope stability models. This study quantifies the relationship between soil physical characteristics and root growth, giving special emphasis on (1) how roots influence the physical architecture of the surrounding soil structure and (2) how soil structure influences the root growth. A systematic experimental study is carried out using high-resolution X-ray micro-computed tomography (µCT) to observe the root behaviour in layered soil. In total, 2 samples are scanned over 15 days, enabling the acquisition of 10 sets of images. A machine learning algorithm for image segmentation is trained to act at 3 different training percentages, resulting in the processing of 30 sets of images, with the outcomes prompting a discussion on the size of the training data set. An automated in-house image processing algorithm is employed to quantify the void ratio and root volume ratio. This script enables post processing and image analysis of all 30 cases within few hours. This work investigates the effect of stratigraphy on root growth, along with the effect of image-segmentation parameters on soil constitutive properties.

X-Ray Computed Tomography for 3D Anatomical Analysis of Resin Ducts.

Digital imaging using high-resolution X-ray micro-computed tomography has become a methodology with increasing importance for assessing wood tissues. This chapter aims to describe the use of this nondestructive, noninvasive, and reproducible technique to new researchers interested in analyzing the three-dimensional properties of the resin duct systems in pine stem wood samples.