Yield Criteria for Ductile Porous Solids

Control of pore window size is the standard approach for tuning gas selectivity in porous solids. Here, we present the first example where this is translated into a molecular porous liquid formed from organic cage molecules. Reduction of the cage window size by chemical synthesis switches the selectivity from Xe-selective to CH4-selective, which is understood using 129Xe, 1H, and pulsed-field gradient NMR spectroscopy.

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Controlling Gas Selectivity in Molecular Porous Liquids by Tuning the Cage Window Size

10.26434/chemrxiv.10247528 ◽

2019 ◽

Author(s):

Benjamin Egleston ◽

Konstantin V. Luzyanin ◽

Michael C. Brand ◽

Rob Clowes ◽

Michael E. Briggs ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Chemical Synthesis ◽

Field Gradient ◽

Window Size ◽

Standard Approach ◽

Porous Solids ◽

Pulsed Field Gradient Nmr ◽

Pulsed Field ◽

Cage Molecules ◽

Gas Selectivity

Control of pore window size is the standard approach for tuning gas selectivity in porous solids. Here, we present the first example where this is translated into a molecular porous liquid formed from organic cage molecules. Reduction of the cage window size by chemical synthesis switches the selectivity from Xe-selective to CH4-selective, which is understood using 129Xe, 1H, and pulsed-field gradient NMR spectroscopy.

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Two Consecutive Magneto-Structural Gas-Solid Transformations with Single-Crystal Retention in Non-Porous Molecular Materials

10.26434/chemrxiv.6291671 ◽

2018 ◽

Author(s):

Julia Miguel-Donet ◽

Javier López-Cabrelles ◽

Nestor Calvo Galve ◽

Eugenio Coronado ◽

Guillermo Minguez Espallargas

Keyword(s):

Solid State ◽

Single Crystal ◽

Structural Rearrangement ◽

Magnetic Behaviour ◽

Porous Solids ◽

Potential Applications ◽

Hcl Gas ◽

Porous Coordination Polymer ◽

Gas Molecules ◽

Magnetostructural Transformation

Modification of the magnetic properties in a solid-state material upon external stimulus has attracted much attention in the recent years for their potential applications as switches and sensors. Within the field of coordination polymers, gas sorption studies typically focus on porous solids, with the gas molecules accommodating in the channels. Here we present a 1D non-porous coordination polymer capable of incorporating HCl gas molecules, which not only causes a reordering of its atoms in the solid state but also provokes dramatic changes in the magnetic behaviour. Subsequently, a further solid-gas transformation can occur with the extrusion of HCl gas molecules causing a second structural rearrangement which is also accompanied by modification in the magnetic path between the metal centres. Unequivocal evidence of the two-step magnetostructural transformation is provided by X-ray single-crystal diffraction.

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The Effect of Void Arrangement on the Pattern Transformation of Porous Soft Solids under Biaxial Loading

Materials ◽

10.3390/ma14051205 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1205

Author(s):

Hai Qiu ◽

Ying Li ◽

Tianfu Guo ◽

Shan Tang ◽

Zhaoqian Xie ◽

...

Keyword(s):

Biaxial Loading ◽

Tensile Deformation ◽

Biaxial Stress ◽

Porous Solids ◽

Biaxial Compression ◽

Structural Topology ◽

Soft Solids ◽

Tension And Compression ◽

Inclined Angle ◽

Pattern Transformation

Structural topology and loading condition have important influences on the mechanical behaviors of porous soft solids. The porous solids are usually set to be under uniaxial tension or compression. Only a few studies have considered the biaxial loads, especially the combined loads of tension and compression. In this study, porous soft solids with oblique and square lattices of circular voids under biaxial loadings were studied through integrated experiments and numerical simulations. For the soft solids with oblique lattices of circular voids, we found a new pattern transformation under biaxial compression, which has alternating elliptic voids with an inclined angle. This kind of pattern transformation is rarely reported under uniaxial compression. Introducing tensile deformation in one direction can hamper this kind of pattern transformation under biaxial loading. For the soft solids with square lattices of voids, the number of voids cannot change their deformation behaviors qualitatively, but quantitatively. In general, our present results demonstrate that void morphology and biaxial loading can be harnessed to tune the pattern transformations of porous soft solids under large deformation. This discovery offers a new avenue for designing the void morphology of soft solids for controlling their deformation patterns under a specific biaxial stress-state.

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On the Weyl transform for rotationally invariant symbols

Journal of Pseudo-Differential Operators and Applications ◽

10.1007/s11868-019-00312-3 ◽

2019 ◽

Vol 10 (4) ◽

pp. 769-791 ◽

Cited By ~ 1

Author(s):

Norbert Ortner ◽

Peter Wagner

Keyword(s):

Asymptotic Behavior ◽

Differential Operators ◽

Symmetric Distributions ◽

Yield Criteria ◽

Weyl Transform ◽

Pseudo Differential Operators ◽

Weyl Transforms ◽

Rotationally Invariant

Abstract Several formulas for the eigenvalues $$\lambda _j$$ λ j of the Weyl transforms $$W_\sigma $$ W σ of symbols $$\sigma $$ σ given by radially symmetric distributions are derived. These yield criteria for the boundedness and the compactness, respectively, of the pseudo-differential operators $$W_\sigma .$$ W σ . We investigate some examples by analyzing the asymptotic behavior of $$\lambda _j$$ λ j for $$j\rightarrow \infty $$ j → ∞ .

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