Arraying Shape-Persistent Molecular Alkynyl Trap into Highly Porous and Robust Zirconium Metal-Organic Framework for Propyne Capture and Propyne/Propylene Separation.

July 29, 2026| Source: Journal of the American Chemical Society

Adsorptive separation of propyne/propylene (C3H4/C3H6) using porous adsorbents offers a promising route toward energy-efficient production of polymer-grade C3H6. Currently, the prevailing adsorbents are ultramicroporous metal-organic frameworks (MOFs) that feature narrow channels and/or consist of inorganic anion pillars, which often lead to limited C3H4 uptake capacity and high isosteric enthalpy of adsorption. We report herein a highly porous and robust zirconium metal-organic framework, termed SJTU-520. This MOF incorporates shape-persistent molecular arrays in three-dimensional space derived from cyclotetrabenzoin, which function as selective sites for the preferential entrapment of C3H4 over C3H6, thus enabling high C3H4 capture capacity, record high C3H4/C3H6 uptake ratio at 1 bar and 298 K, and efficient C3H4/C3H6 separation at ambient conditions. Compared with the cyclotetrabenzoin and tetraacetate cyclotetrabenzoin-based supramolecular organic crystals, SJTU-520 exhibits significantly higher surface area (3650 m2/g versus 42 and 570 m2/g), leading to a C3H4 uptake boost by 6.1-fold and 3.7-fold at 298 K and 1 bar, without any compromise of the C3H4/C3H6 selectivity. The efficient C3H4/C3H6 separation was validated by extensive breakthrough experiments under various conditions with great recyclability and high productivity of polymer-grade C3H6 from a 10/90 C3H4/C3H6 mixture. Computational simulations revealed that the four benzene walls of the cyclotetrabenzoin macrocycle in SJTU-520 formed equidistant π-π interactions with the C≡C triple bond of encapsulated C3H4 molecule. This work illustrates a general and powerful strategy─the reticulation of intrinsically functional organic scaffolds into highly porous frameworks─toward creating bespoke materials with precisely tailored functionalities and enhanced properties.

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Reversing vegetable biodiversity loss to diversify diets.

Vegetables are a critical component of diets, with inadequate intake of this essential food group leading to poor dietary quality and malnutrition. Food system assessments identify insufficient production, comparatively high prices, and sociocultural barriers as key constraints to vegetable consumption. We argue that vegetable biodiversity, spanning vegetable species and their varieties, as well as their wild relative species, is a central yet underutilized lever for enhancing vegetable consumpt

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Sediment accumulation rate predicts the temporal resolution of marine fossil assemblages.

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Geometry controls momentum flux in the sprinkler problem.

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Guanidine fuels rapid resurrection of desert cyanobacteria.

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EnvironmentJuly 28, 2026

The unique Efg1 fungal virulence regulon in the catheterized bladder environment.

Urinary catheterization, a frequent procedure in hospitals, nursing homes, and other healthcare facilities, is a primary driver of nosocomial infections. The most common of these are catheter-associated urinary tract infections (CAUTIs), which often progress to severe complication, sepsis, and ultimately death. The fungus Candida albicans is a primary causative agent of CAUTIs; yet, its tissue-specific pathogenesis remains poorly understood, which complicates development of efficient treatments.