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Showing 1 to 15 of 15 for “"Grain shape"”.
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Identification of Fold Hinge Migration in Natural Deformation: A New Technique Using Grain Shape Fabric Analysis
… associated with the folding event. Rf/phi grain shape fabric analysis was conducted for each sample and used to calculate the orientation and magnitude of the final grain shape fabric ellipsoids. Flexural folding and passive-shear folding models predict that the highest finite strains will …
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Mesoscale Forces and Grain Motion in Granular Media Exhibiting Stick-Slip Dynamics: Effects of Friction and Grain Shape
… is understanding how the properties of single grains, such as grain shape and friction, influence the mechanical strength and dynamical response of the bulk granular material. While spherical grains are often used to study granular materials in experiments and simulations, the interactions …
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Quantitative textural analysis of sedimentary grains and basin subsidence modelling
Part 1: Quantitative textural analysis Shape analysis can provide important information regarding the origin, transport and deposition history of grains. Particle shape measurement has been an active area of research for sedimentologists since the 20th century. However, there is a lack of …
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Microstructural and crystallographic fabric analysis of stretched-pebble conglomerates in central Vermont
… pebbles suggest dynamic recrystallization via subgrain rotation and grain boundary migration. Dynamically recrystallized quartz grains have a grain shape preferred orientation, which is parallel to a series of intracrystalline strain features including undulatory extinction, deformation bands, and …
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Models of high-temperature desulfurization using zinc-based sorbents
… of TGA experiments. Variations of the GPM (Grainy Pellet Model) were used and shown to give good agreement with experimental conversion histories of zinc oxide particle undergoing sulfidation using H2S at temperature in the range of 482 to 593 degree centigrade.;By using SEM (Scanning …
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The origin of recumbent fold nappes: The Lochalsh fold as the main example
… Using a variety of techniques, including grain shape analysis, measurement of conglomerate pebbles, magnetic anisotropy and palaeomagnetism strain patterns have been obtained for these nappes. Different rock types control the style of folding, and, in part, the sequence of structures …
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Radiative transfer modeling of thermal infrared emissivity spectra: applications to martian regolith observations
… models for interpretation of constituent grain physical properties. However, such models have remained in stasis in recent years, with nearly a ten-year gap in significant advances. To date, no radiative transfer model (semiempirical, exact, or hybrid solution) has been able to adequately …
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Shape and Texture in Quartz Sand Grains: A Quantitative Assessment
Thirty years of microtextural study of quartz grain form has revealed many different textural types and shapes. In conjunction with other sedimentological methods, surface textures and shapes have been assigned to quartz grains from a variety of depositional settings. Many different methods have …
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Study of fault gouge influences on mechanical and frictional behavior of granular shear zones using the distinct element method
… of fault zones. Granular assemblages of multiple shaped grains were sheared over a range of normal stresses, sigman, in order to examine the influences of sigman gouge grain shape, grain comminution, and associated dynamic changes in grain characteristics on the frictional behavior of granular …
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Stress Transmission in a Granular System
… These external loads are propagated through grain-to-grain contacts. Consequently, the grains are being subjected to both tensile and compressive stresses according to their shape, position, and number of contacts. Thus, the nonlinear mechanical behaviour of soil may be described by …
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Effective Thermal Properties of Granular Porous Media: A Numerical Study using Lattice Blotzmann Methods
… of morphological features of the medium such as grain shape, grain size, and geometrical structure. Thermal contact resistance can also affect heat conduction due to topological features such as the surface profile of the grain. Furthermore, the compressive pressure and presence of different …
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Biogenic buildups and carbonate sedimentation, Dry Tortugas Reef Complex, Florida
<p>The Dry Tortugas, a horseshoe-shaped complex of carbonate banks and coral reefs, is located at the southern terminus of the Florida limestone shelf. The complex rises to the surface waters from a drowned Pleistocene surface that forms a circular platform having a general depth of 17-21 m.</p> …
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Exploring the Stochastic Performance of Metallic Microstructures With Multi-Scale Models
… characterizing microstructural features such as grain size and grain shape. While the relationship between homogenized material properties and grain sizes of microstructures is well-studied through the Hall-Petch effect, the influences of grain shapes, especially in complex additively …
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Processing-microstructure-property relationships in additively manufactured duplex stainless steels
… of AM DSS materials, specifically the grain size, grain shape, and texture. To boost the speed and efficiency of the characterization of processing-microstructure-property relationships for DSS alloys, thermomechanical simulations to simulate AM thermal histories using Joule heating …
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Integrating rotational components to optical properties observed in petrographic thin sections via automated image acquisition and analysis
… alters the set of observed properties for each grain. Since the range of colour values upon rotation are more indicative than a single value at one orientation these are then attributed as ranges to each pixel. Grain segmentation is performed on these images and the pixel values are extracted …