Fractal structure of porous solids characterized by adsorption

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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FRACTAL STRUCTURE AND PROPERTIES OF SOFT MAGNETIC POWDER MATERIAL OF THE ALLOYING SYSTEM Fe-P

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2017-83-12-29-33 ◽

2017 ◽

Vol 83 (12) ◽

pp. 29-33 ◽

Cited By ~ 1

Author(s):

A. Yu. Kem

Keyword(s):

Powder Material ◽

Fractal Structure ◽

Magnetic Powder ◽

Structure And Properties ◽

Soft Magnetic ◽

Alloying System

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Rapid determination of fractal structure of bacterial assemblages in wastewater treatment: implications to process optimisation

Water Science & Technology ◽

10.2166/wst.1998.0092 ◽

1998 ◽

Vol 38 (2) ◽

pp. 9-15 ◽

Cited By ~ 3

Author(s):

J. Guan ◽

T. D. Waite ◽

R. Amal ◽

H. Bustamante ◽

R. Wukasch

Keyword(s):

Wastewater Treatment ◽

Fractal Structure ◽

Structural Information ◽

Rapid Determination ◽

Fractal Dimensions ◽

Structure Information ◽

Treatment Processes ◽

On Line ◽

Bacterial Aggregates

A rapid method of determining the structure of aggregated particles using small angle laser light scattering is applied here to assemblages of bacteria from wastewater treatment systems. The structure information so obtained is suggestive of fractal behaviour as found by other methods. Strong dependencies are shown to exist between the fractal structure of the bacterial aggregates and the behaviour of the biosolids in zone settling and dewatering by both pressure filtration and centrifugation methods. More rapid settling and significantly higher solids contents are achievable for “looser” flocs characterised by lower fractal dimensions. The rapidity of determination of structural information and the strong dependencies of the effectiveness of a number of wastewater treatment processes on aggregate structure suggests that this method may be particularly useful as an on-line control tool.

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