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Results for “POROSITY”
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Porosity, permeability, and grain size of sediment cores from gas-hydrate-bearing sites and their implication for overpressure in shallow argillaceous formations: Results from the national gas hydrate program expedition 02, Krishna-Godavari Basin, India
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Neutron dark-field imaging applied to porosity and deformation-induced phase transitions in additively manufactured steels
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Increasing fracture toughness via architected porosity
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Role of side-chain length on gas transport of CO 2 /CH 4 mixtures in polymers with side-chain porosity
Polymers of intrinsic microporosity (PIMs) are traditionally formed from ladder backbones, but recent synthetic advances have allowed for the formation of non-traditional PIMs using a poly(ladder) motif, whereby rigid PIM-like sidechains are appended onto more flexible backbones. The effect of side-chain length on free volume and gas transport properties was recently evaluated for a methoxy-functionalized poly(ladder) (OMe-ROMP). In this study, we elaborate on the role of side-chain length and its influence on mixed-gas performance and plasticization stability for OMe-ROMP. Pure-gas sorption results are also reported, including hysteresis effects from CO 2 conditioning. Taken together, this study reveals the role of side-chain length on gas sorption, diffusion, and plasticization for CO 2 /CH 4 separations. Finally, we conclude that the length of a rigid side chain in the poly(ladder) motif is a valuable structural parameter to control sorption, diffusion, and stability towards plasticization for gas separation membrane materials.
A statistical approach to control porosity in silica-doped alumina supports
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Comparing methods for measuring thickness, refractive index, and porosity of mesoporous thin films
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Enabling high-porosity porous silicon as an electronic material
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Analysis of the interdependent relationship between porosity, deformation, and crack growth during compression loading of LPBF AlSi10Mg
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Latent heat thermal storage with variable porosity metal matrix: A numerical study
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Tectonic significance of porosity and permeability regimes in the red beds formations of the South Georgia Rift Basin
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Helium Ion Microscopy for Imaging and Quantifying Porosity at the Nanoscale
Nanoporous materials are essential components in a vast number of applications from energy to drug delivery and to agriculture. Yet, the number of ways to analytically quantify the salient features of these materials, for example: surface structure, pore shape, and size, remain limited. The most common approach is gas absorption, where volumetric gas absorption and desorption are measured. This technique has some fundamental drawbacks such as low sample throughput and a lack of direct surface visualization. In this work, we demonstrate Helium Ion Microscopy (HIM) as a tool for imaging and quantification of pores in industrially relevant SiO 2 catalyst supports. We start with the fundamental principles of ion-sample interaction, and build on this knowledge to experimentally observe and quantify surface pores by using the HIM and image data analytics. We contrast our experimental results to gas absorption and demonstrate full statistical agreement between two techniques. The principles surrounding the theoretical, experimental, and analytical framework presented herein offer an automated framework for visualization and quantification of pore structures in a wide variety of materials.
Direct Measure of the Dense Methane Phase in Gas Shale Organic Porosity by Neutron Scattering
Here, we report the first direct measurements of methane density in shale gas using small-angle neutron scattering. At a constant pressure, the density of methane in the inorganic pores is similar to the gas bulk density of the system conditions. Conversely, the methane density is 2.1 ± 0.2 times greater in the organic mesopores. Furthermore, classical density functional theory calculations show that this excess density in the organic pores persists to elevated temperatures, typical of shale gas reservoir conditions, providing new insight into the hydrocarbon storage mechanisms within these reservoirs.
Rethinking Porosity-Based Diffusivity Estimates for Sorptive Gas Transport at Variable Temperatures
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