Comments on “M.S. Wu, a pressure loaded soft functionally gradient spherical capsule under finite deformation”, mechanics of materials, 150 (2020) 103573

ABSTRACTA novel approach to quantitative interpretation of high-resolution electron microscopy images of defects in materials has been developed. The emphasis of this paper is on the methodology, which has been named Computational Fourier Transform Moiré Analysis. The essential principle of this technique is to extract an accurate displacement field about a defect from its near-atomic-resolution picture using digital Fourier transformation procedures. From this data, the displacement gradient can be calculated which yields much information on the experimental deformation mechanics of the material under investigation. As a by-product, we produce the computational Moiré pattern without the need of an external perfect reference lattice image normally associated with the interference phenomena. This method is illustrated using a bounding Frank partial dislocation for a Frank loop of the vacancy type. Results are presented on its strain field, Burgers vector and dislocation core shape and dimensions. Further mention will be made on the types of J-integral calculations that can result from this experimental study.

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Enantioselective Recognition of Chiral Guests by the Water-Soluble Chiral Keplerate {Mo132} Spherical Capsule with 30 Inner Lactate Ligands

10.26434/chemrxiv.8847923.v1 ◽

2019 ◽

Author(s):

Nancy Watfa ◽

Weimin Xuan ◽

Zoe Sinclair ◽

Robert Pow ◽

Yousef Abul-Haija ◽

...

Keyword(s):

Aqueous Solution ◽

Chiral Recognition ◽

Association Constants ◽

Water Soluble ◽

Enantioselective Recognition ◽

H Nmr ◽

Dosy Nmr ◽

Spherical Capsule ◽

Surface Pores ◽

Guest Chemistry

Investigations of chiral host guest chemistry are important to explore recognition in confined environments. Here, by synthesizing water-soluble chiral porous nanocapsule based on the inorganic metal-oxo Keplerate-type cluster, {Mo132} with chiral lactate ligands with the composition [Mo132O372(H2O)72(x-Lactate)30]42- (x = D or L), it was possible to study the interaction with a chiral guest, L/D-carnitine and (R/S)-2-butanol in aqueous solution. The enantioselective recognition was studied by quantitative 1H NMR and 1H DOSY NMR which highlighted that the chiral recognition is regulated by two distinct sites. Differences in the association constants (K) of L- and D-carnitine, which, due to their charge, are generally restricted from entering the interior of the host, are observed, indicating that their recognition predominantly occurs at the surface pores of the structure. Conversely, a larger difference in association constants (KS/KR = 3) is observed for recognition within the capsule interior of (R)- and (S)-2-butanol.

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