(11) Metal–organic framework (MOF) membranes have recently aroused great interest in separation applications owing to their high surface areas providing ample adsorption sites for guests, precise control over pore metrics, and easily functionalizable pore walls. (8−10) However, the shortcoming is the low water flux owing to the (a) dearth of sp 2 domains of pristine graphene and (b) oxygen-rich functional groups obstructing the space for water passage by the formation of hydrogen bonding. (6,7) Graphene oxide (GO) membranes are interesting platforms for wastewater reclamation owing to their tunable molecular sieving by adjusting the interlayer spacing in GO laminates, easy dispersibility of GO sheets and their inclusion in polymer matrices, and their oxygen-rich functional groups enabling the preparation of GO-based composites. (6) Nevertheless, membrane fouling and the permeability–selectivity trade-off are some of the critical challenges hindering the adoption of polymer membranes in water purification. (5) The core advantage of polymeric membranes is its processability and excellent mechanical properties. Membranes hold significant potential for water treatment, attributed to their high separation selectivity, small footprint, cost and energy efficiency, and scalability. The stoichiometric imbalance approach presented herein offers a different route to COF membrane fabrication and may impart with an unprecedented control handle on the permeability and separation selectivity of COF membranes. In particular, the in situ construction of hydrophilic nanospaces partaking in high water uptake and hydrophobic nanospaces facilitating fast water diffusion in a single COF structure endows the TUS-46 membranes with unprecedentedly high water flux. Attributed to the free aldehyde functionalities in the framework resulting from unbalanced stoichiometry, the TUS-46 COF membrane also shows a 10-fold higher water permeance compared to the analogue COF membrane without free aldehyde functionalities. Credited with pore sizes befitting for size-selective molecular exclusion and negative electrostatic pore walls, the TUS-46 COF membrane shows excellent rejection performance toward anionic dyes. To reach both the criteria, we herein precisely design the pore metrics and pore functionalities to prepare a covalent organic framework (COF), termed TUS-46, membrane. Regarding water permeation, filtration experiments accentuate the importance of hydrophilic pores in enhancing the water adsorption capacity, while hydrophobic pores enable low-friction water diffusion. Particularly important is the pore-size control designed for molecular sieving. Both Morgan and Mobley get brief star turns, the younger trumpeter blasting away first and the saxophonist rising to match his energy.Membrane separation is making substantial contributions to water purification. They include two tunes that had never been released in any form - including “Quick Trick,” a sauntering ditty composed by the pianist Bobby Timmons (the author of “Moanin’,” the Messengers’ de facto theme song). That music will see the light of day in April, when Blue Note releases “Just Coolin’,” featuring six tracks from that session. No studio album has been released featuring this particular crew but enough material was recorded for one, at a session 61 years ago this month. One historic formation that existed only briefly (in 1959, jazz’s banner year) put the tenor saxophonist Hank Mobley alongside the trumpeter Lee Morgan on the band’s front line. The Jazz Messengers were the quintessential outfit of the hard-bop era, but as a finishing school for young jazz musicians on their way to illustrious careers, the band had no fixed membership.
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