Highly stabilized and efficient thermoelectric copper selenide.

The liquid-like feature of thermoelectric superionic conductors is a double-edged sword: the long-range migration of ions hinders the phonon transport, but their directional segregation greatly impairs the service stability. We report the synergetic enhancement in figure of merit (ZT) and stability in Cu1.99Se-based superionic conductors enabled by ion confinement effects. Guided by density functional theory and nudged elastic band simulations, we elevated the activation energy to restrict ion migrations through a cation-anion co-doping strategy. We reduced the carrier concentration without sacrificing the low thermal conductivity, obtaining a ZT of ∼3.0 at 1,050 K. Notably, the fabricated device module maintained a high conversion efficiency of up to ∼13.4% for a temperature difference of 518 K without obvious degradation after 120 cycles. Our work could be generalized to develop electrically and thermally robust functional materials with ionic migration characteristics.

A macro-nano-atomic-scale high-throughput approach for material research.

Understanding the properties of materials requires structural characterization over large areas and different scales to link microstructure with performance. Here, we demonstrate a single-beam high-throughput scanning electron microscope allowing the collection of both secondary electron and backscattered electron signals over large areas. Combined with machine learning, a high efficiency in material research is achieved, illustrated here by a multiscale investigation of carbides in a second-generation nickel-base single-crystal superalloy. The resulting terabyte-sized panoramic atlas data, combined with conventional electron microscopy, enable a simultaneous multiscale analysis of carbide evolution during creep regarding specific type, location, composition, size, shape, and relationship with the matrix, providing sample-scale quantitative statistical data and giving a precise insight into the effect of carbides in the superalloy in a way not previously possible.

Aurintricarboxylic acid inhibits influenza virus neuraminidase.

There is a continuing threat that the highly pathogenic avian influenza virus will cause future influenza pandemics. In this study, we screened a library of compounds that are biologically active and structurally diverse for inhibitory activity against influenza neuraminidase (NA). We found that aurintricarboxylic acid (ATA) is a potent inhibitor of NA activity of both group-1 and group-2 influenza viruses with IC(50)s (effective concentration to inhibit NA activity by 50%) values at low micromolar concentrations. ATA was equally potent in inhibiting the NA activity derived from wild-type NA and its H274Y mutant which renders NA resistance to inhibition by oseltamivir. Although ATA is structurally distinct from sialic acid, molecular modeling experiments suggested that ATA binds to NA at the enzyme's substrate binding site. These results indicate that ATA may be a good starting material for the design of a novel class of NA inhibitors for the treatment influenza viruses.