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Controlling coalescence events in a heterogeneous ensemble of condensing droplets on a surface is an outstanding fundamental challenge in surface and interfacial sciences, with a broad practical importance in applications ranging from thermal management of high-performance electronic devices to moisture management in high-humidity environments. Nature-inspired superhydrophobic surfaces have been actively explored to enhance heat and mass transfer rates by achieving favorable dynamics during dropwise condensation; however, the effectiveness of such chemically homogeneous surfaces has been limited because condensing droplets tend to form as pinned Wenzel drops rather than mobile Cassie ones. Here, we introduce an amphiphilic nanostructured surface, consisting of a hydrophilic base with hydrophobic tips, which promotes the periodic regeneration of nucleation sites for small droplets, thus rendering the surface self-rejuvenating. This unique amphiphilic nanointerface generates an arrangement of condensed Wenzel droplets that are fluidically linked by a wetted sublayer, promoting previously unobserved coalescence events where numerous droplets simultaneously merge, without direct contact. Such ensemble coalescences rapidly create fresh nucleation sites, thereby shifting the overall population toward smaller droplets and enhancing the rates of mass and heat transfer during condensation.

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Carbon nanopearls have a unique layered structure made of nano-sized graphene fragments, which distinguishes them from closed-shell nano-carbons. This unique structure offers beneficial tribological properties which were evaluated in humid and dry environments. The lubricating effect was related to an easy shear of nano-sized graphene flakes from individual nanopearls.

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High heat dissipation rates are enabled by multi-phase cooling schemes owing to latent heat uptake. We demonstrate enhanced flow boiling from a carbon nanotube (CNT)-coated copper surface exposed to low-intensity ultraviolet (UV)-visible excitation. Compared to non-illuminated results, the average boiling incipience temperature decreased by 4.6 C and heat transfer coefficients improved by 41.5% with light exposure. These improved results are attributed to augmented hydrophilicity upon exposure to UV light and possible nanoscale opto-thermal effects, and suggest opportunities for active temperature control of temperature-sensitive devices.

The title compound, C9H11NOS, exhibits a unique structural motif, with free rotation of the aliphatic oxathiane ring about the C—C bond connecting this moiety to the aromatic pyridine ring. The structure elucidation was undertaken due to its potential as a bidentate ligand for organometallic complexes. The oxathiane ring adopts the expected chair conformation, with the S atom in proximity to the N atom on the pyridine ring. The corresponding S—C—C—N torsion angle is 69.07 (14)°. In the crystal, mol­ecules aggregate as centrosymmetric pairs connected by pairs of C—H⋯N hydrogen bonds.