Although China's low-permeability and tight oil reservoir utilization and newly proven reserves are growing annually, the overall recovery of such reservoirs is generally low. One of the main factors influencing the low recovery is the effect of intricate dynamic fracture propagations on the remaining oil distribution. Constrained by the evolution of an in situ stress field and the accumulation of fluid injection volumes, the growth of dynamic fractures allows a production profile of water breakthrough.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2024
Angew Chem Int Ed Engl
August 2024
Here, we successfully synthesized four structurally analogous, self-assembled chiral molecular tubes with relatively high yields. This achievement involved the condensation of six equivalents of enantiomerically pure trans-cyclohexane-1,2-diamine (trans-CHDA) and three equivalents of the corresponding tetraformyl precursor. Each precursor was equipped with a luminescent linker terminated by two m-phthalaldehyde units.
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September 2022
A triangular-prism shaped cage was self-assembled by the formation of a dynamic covalent bond, namely a hydrazone, in acidic aqueous solution. The hexacationic host bears a number of relatively acidic protons pointing inside the cage cavity, which is able to accommodate an iodide anion selectively in water over other halide anions such as F , Cl , and Br , which are more hydrated. As a comparison, a macrocycle analogue bearing fewer positive charges and fewer hydrogen bond donors shows no anion binding ability.
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August 2021
Self-assembly of host molecules in aqueous media via metal-ligand coordination is well developed. However, the preparation of purely covalent counterparts in water has remained a formidable task. An anionic tetrahedron cage was successfully self-assembled in a [4+4] manner by condensing a trisamine and a trisformyl in water.
View Article and Find Full Text PDFHerein, we report the self-assembly of an anionic homochiral octahedral cage by condensing six Ga cations and four trisacylhydrazone ligands. The robust nature of the hydrazone bond renders the cage stable in water, where it can take advantage of the hydrophobic effect for host-guest recognition. In addition to the internal binding site, namely, the inner cavity, the octahedral cage possesses four "windows", each of which represents an external binding site allowing peripheral complexation.
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