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Abstract Cyclotetrabenzil, a shape‐persistent macrocyclic octaketone, is found to undergo eightfold condensation with hydroxylamine hydrochloride to yield its octaoxime. Subsequent acetylation of this macrocyclic oxime afforded the corresponding octaoxime acetate. Single‐crystal X‐ray diffraction reveals that both new derivatives assemble into nanotubular structures. However, their packing differs: the oxime forms hydrogen‐bonded tubes that bundle via included dimethyl sulfoxide (DMSO) molecules, whereas the acetate—lacking hydrogen‐bond donors—forms more loosely packed tubes with molecules tilted ∼54.5° relative to the tube axis. Gas sorption studies (CO₂, C₂, and C₃hydrocarbons) show that cyclotetrabenzil is nonporous, whereas the oxime and acetate exhibit modest microporosity with BET surface areas of ∼200 m²g⁻¹. Both derivatives display preferential uptake of propyne over propene and propane, and the acetate also adsorbs more acetylene than ethylene or ethane. Nonetheless, these capacities and selectivities are suboptimal for dynamic separation of C₂and C₃hydrocarbons. This study illustrates how oxime functionalization can modulate macrocyclic assembly and gas uptake behavior, providing insights for the design of future porous organic macrocycles. 

Abstract Two new partially fluorinated dehydrobenzannulenes have been prepared by inter‐ and intramolecular oxidative homocoupling of diyne precursors. These systems contain fluorinated and nonfluorinated arene rings in a desymmetrized non‐alternant arrangement. Both macrocycles are roughly planar and organize into extended columns in the solid state. The assembly of these columns is mediated by the combination of dispersion interactions, slipped [π⋅⋅⋅π] stacking interactions of the perfluorinated rings with each other, and their association with the nonfluorinated rings in the molecules of the neighboring macrocycles. These results suggest that partial fluorination of dehydrobenzannulenes can serve as a versatile motif for their assembly into columnar superstructures. 

Abstract. Intense tropical cyclones (TCs) can cause catastrophic damage to coastal regions after landfall. Recent studies have linked the devastation associated with TCs to climate change, which induces favorable conditions, such as increasing sea-surface temperature, to supercharge storms. Meanwhile, environmental factors, such as atmospheric aerosols, also impact the development and intensity of TCs, but their effects remain poorly understood, particularly coupled with ocean dynamics. Here, we quantitatively assess the aerosol microphysical effects and aerosol-modified ocean feedbacks during Hurricane Katrina using a cloud-resolving atmosphere–ocean coupled model: Weather Research and Forecasting (WRF) in conjunction with the Regional Ocean Model System (ROMS). Our model simulations reveal that an enhanced storm destructive power, as reflected by larger integrated kinetic energy, heavier precipitation, and higher sea-level rise, is linked to the combined effects of aerosols and ocean feedbacks. These effects further result in an expansion of the storm circulation with a reduced intensity because of a decreasing moist static energy supply and enhancing vorticity Rossby wave outward propagation. Both accumulated precipitation and storm surge are enhanced during the mature stage of the TC with elevated aerosol concentrations, implying exacerbated flood damage over the polluted coastal region. The ocean feedback following the aerosol microphysical effects tends to mitigate the vertical mixing cooling in the ocean mixing layer and offsets the aerosol-induced storm weakening by enhancing cloud and precipitation near the eyewall region. Our results highlight the importance of accounting for the effects of aerosol microphysics and ocean-coupling feedbacks to improve the forecast of TC destructiveness, particularly near the heavily polluted coastal regions along the Gulf of Mexico. 

The measurement of vital signs (such as respiration rate, body temperature, pulse, and blood pressure), especially during strenuous activities, is essential for physical performance and health monitoring. A variety of wearable chest band sensors have been developed, commercialized, and widely used in consumer and healthcare settings. The plethora of technology choices also means that each unique chest band sensor may require different data acquisition hardware and software systems, and data may not be transferable between platforms. Therefore, the objective of this work was to develop a low-cost, disposable, respiration sensor that could be attached onto any elastic chest band. The approach was to spray-coat graphene nanosheet (GNS)-based thin films onto unidirectionally stretchable elastic fabric to form a piezoresistive material. Snap buttons were incorporated at the ends of the fabric so that they could be attached onto any chest band, removed at any time, and replaced for a new data collection event. The resistive nature of the nanocomposite sensor means that they can be easily interfaced (e.g., using a voltage divider) with any existing data acquisition (DAQ) module while adding respiration monitoring capabilities. To facilitate testing of these nanocomposite respiration sensors, a miniature DAQ module with four sensing channels was also prototyped. Then, tests were performed with human subjects wearing a nanocomposite chest band and a reference commercial respiration monitoring chest band. Simultaneous measurements of subject respiration verified the respiration monitoring performance of these low-cost, disposable, nanocomposite fabric sensors.