Zwitterionic Polymer Gradient Interphases for Reversible Zinc Electrochemistry in Aqueous Alkaline Electrolytes

Aqueous alkaline zinc batteries are of scientific and technological interest because of the potential they offer for cost-effective and safe storage of electrical energy. Poor electrochemical reversibility and shape change of the Zn anode, propensity of Zn to become passivated by surface oxides and hydroxide films upon prolonged exposure to the electrolyte, and electroreduction of water are well-studied but remain unsolved challenges. Here, we create and study electrochemical and transport properties of precise, spatially tunable zwitterionic polymer interphases grown directly on Zn using an initiated-chemical vapor deposition polymerization methodology. In aqueous alkaline media, spatial gradients in compositionfrom the polymer–electrolyte interface to the solid–polymer interfacepromote highly reversible redox reactions at high current density (20 mA cm–2) and high areal capacity (10 mAh cm–2). Via molecular dynamics and experimental analyses, we conclude that the interphases function by regulating the distribution and activity of interfacial water molecules, which simultaneously enables fast ion transport and suppression of surface passivation and the hydrogen evolution reaction. To illustrate the practical relevance of our findings, we study aqueous Zn||NiOOH and Zn||air batteries and observe that zwitterionic polymer interphases produce extended life at high currents and high areal capacity

Phylogenetic analysis among 27 Chinese populations and genetic polymorphisms of 20 autosomal STR loci in a Chinese Uyghur ethnic minority group

<p>Allele frequency data and forensic statistical parameters were determined for 20 autosomal short tandem repeat (STR) loci of the PowerPlex 21 System in 214 unrelated healthy individuals of a Uyghur ethnic minority group living in Xinjiang province, northwest China. A total of 232 alleles were observed with the corresponding allele frequencies ranging from 0.0023 to 0.5304. All loci were consistent with Hardy–Weinberg equilibrium (HWE) after the Bonferroni correction (<i>p</i> > 0.0025). The combined probability of exclusion, power of discrimination, probability of matching value were 0.999999999, 0.9999999999999999999999995, and 4.78246 × 10⁻²⁵, respectively. Our results revealed that the 20 STRs were highly polymorphic and informative, and could be suitable for forensic application, especially parentage test and personal identification. The further population comparison between the Uyghur and other 26 reference populations revealed that the loci of D13S317, TH01 and D6S1043 showed high ethnical specificity. Phylogenetic analysis based on 19 shared loci demonstrated that the Uyghur had a close genetic relationship with the Kazakh, but a distinct genetic distance with other Chinese populations from different ethnicity and regions.</p

High-Operation-Temperature Plasmonic Nanolasers on Single-Crystalline Aluminum

The recent development of plasmonics has overcome the optical diffraction limit and fostered the development of several important components including nanolasers, low-operation-power modulators, and high-speed detectors. In particular, the advent of surface-plasmon-polariton (SPP) nanolasers has enabled the development of coherent emitters approaching the nanoscale. SPP nanolasers widely adopted metal–insulator–semiconductor structures because the presence of an insulator can prevent large metal loss. However, the insulator is not necessary if permittivity combination of laser structures is properly designed. Here, we experimentally demonstrate a SPP nanolaser with a ZnO nanowire on the as-grown single-crystalline aluminum. The average lasing threshold of this simple structure is 20 MW/cm², which is four-times lower than that of structures with additional insulator layers. Furthermore, single-mode laser operation can be sustained at temperatures up to 353 K. Our study represents a major step toward the practical realization of SPP nanolasers