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Support Pore Structure and Composition Strongly Influence the Direct Air Capture of CO 2 on Supported Amines
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Continuous Variation of Lattice Dimensions and Pore Sizes in Metal–Organic Frameworks
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Side-Chain Length and Dispersity in ROMP Polymers with Pore-Generating Side Chains for Gas Separations
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Consequences of Pore Polarity and Solvent Structure on Epoxide Ring-Opening in Lewis and Brønsted Acid Zeolites
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Structural and Functional Analysis of mRNA Export Regulation by the Nuclear Pore Complex
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Keyhole fluctuation and pore formation mechanisms during laser powder bed fusion additive manufacturing
Keyhole porosity is a key concern in laser powder-bed fusion (LPBF), potentially impacting component fatigue life. However, some keyhole porosity formation mechanisms, e.g., keyhole fluctuation, collapse and bubble growth and shrinkage, remain unclear. Using synchrotron X-ray imaging we reveal keyhole and bubble behaviour, quantifying their formation dynamics. The findings support the hypotheses that: (i) keyhole porosity can initiate not only in unstable, but also in the transition keyhole regimes created by high laser power-velocity conditions, causing fast radial keyhole fluctuations (2.5-10 kHz); (ii) transition regime collapse tends to occur part way up the rear-wall; and (iii) immediately after keyhole collapse, bubbles undergo rapid growth due to pressure equilibration, then shrink due to metal-vapour condensation. Concurrent with condensation, hydrogen diffusion into the bubble slows the shrinkage and stabilises the bubble size. The keyhole fluctuation and bubble evolution mechanisms revealed here may guide the development of control systems for minimising porosity.
In situ generation of (sub) nanometer pores in MoS2 membranes for ion-selective transport
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Tomographic mapping of the nanoscale water-filled pore structure in corroded borosilicate glass
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Structural and kinetic changes to small-pore Cu-zeolites after hydrothermal aging treatments and selective catalytic reduction of NO[subscript x] with ammonia
Abstract not provided
Salt nanoconfinement in zirconium-based metal–organic frameworks leads to pore-size and loading-dependent ionic conductivity enhancement
Confinement of the salt [NEt 4 ][TFSI] in metal–organic frameworks leads to a significant enhancement in ionic conductivity, pointing toward a novel method of creating solid ion conductors.
H 2 /CO 2 separations in multicomponent metal-adeninate MOFs with multiple chemically distinct pore environments
Tailorable multicomponent MOFs and MOF membranes for efficient H 2 /CO 2 separation.
Insights into the 3D permeable pore structure within novel monodisperse mesoporous silica nanoparticles by cryogenic electron tomography
Synthetic mesoporous silica nanoparticle (MSN) is an architected geomaterial that provides confinement-mediated flow and transport properties of fluids needed for environmental research such as subsurface energy storage or carbon capture.
Tuning the pore chemistry of Zr-MOFs for efficient metal ion capture from complex streams
Metal–organic frameworks (MOFs) have shown promise for adsorptive separations of metal ions. Herein, MOFs based on highly stable Zr(IV) building units were systematically functionalized with targeted metal binding groups. In this study, through competitive adsorption studies, it was shown that the selectivity for different metal ions was directly tunable through functional group chemistry.