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Anion templated assembly of supramolecular systems has been extensively explored in previous reports, whereas anions serve only as an auxiliary and spectator role. With the development of anion coordination chemistry in recent years, anion coordination-driven assembly (ACDA) has emerged as a new strategy for the construction of supramolecular self-assemblies. Anions are proved to exist as the main actors in the construction of supramolecular architectures, i. e., serve as the coordination center. This Review will focus on the recent progress in anion-coordination-driven assembly of discrete supramolecular architectures, such as helicates, polyhedrons and polygons, and the various applications of 'aniono'-systems. At the end of this Review, we highlight current challenges and opportunities for future research of anion-coordination-driven self-assembly.

Large gradients of physical variables near the channel walls are characteristic of EOF. The previous numerical simulations of EOFs with the lattice Boltzmann method (LBM) utilize uniform lattice and are not efficient, especially when the electric double layer (EDL) thickness is significantly smaller than the channel height. The efficient LBM simulation of EOF in microchannel calls for a nonuniform mesh which is dense in the EDL region and sparse in the bulk region. In this article, we formulate a radial basis function (RBF)-based interpolation supplemented LBM (ISLBM) to solve the governing equations of EOF, that is, the Poisson, Nernst-Planck, and Navier-Stokes equations, in a nonuniform mesh system. Unlike the conventional ISLBM, the RBF-ISLBM determines the prestreaming distribution functions by using the local RBF-based interpolation over circular supporting regions and is particularly suitable for nonuniform meshes. The RBF-ISLBM is validated by the EOFs in infinitely long and finitely long microchannels. The results show that the RBF-ISLBM possesses excellent robustness and accuracy. Finally, we use the RBF-ISLBM to simulate the EOFs with the hitherto highest electrokinetic parameter, κa, defined by the ratio of channel height a to EDL thickness κ-1 , in LBM simulations of EOF.

This paper utilizes a combined approach of the convection-diffusion theory and the moment analysis to conduct a comprehensive investigation of the solute dispersion under the influence of the interphase transport in finitely long inner coated microchannels. The present work has threefold novel contributions: (1) The 2D solute concentration contours in the stationary phase are calculated for the first time to facilitate the understanding the role of the interphase transport in the solute dispersion in the mobile phase. (2) The skewness of the elution curves is investigated to guide the control of solute band shape at the channel outlet. (3) The 2D diffusion-convection theory and zero-dimensional (0D) moment analysis complement each other to present a characterization of the solute dispersion behaviors more comprehensive than that by either of the two methods alone. Parametric studies are performed to clarify the effects of four major parameters related to the interphase transport (i.e., stationary phase Péclet number, interphase transport rate, partition coefficient, and stationary phase thickness) on the solute dispersion characteristics. The results from this study provide a straightforward understanding of the effects of interphase transport on the solute dispersion in finitely long microchannels and are of potential relevance to the design and operation of the microfluidics-based analytical devices.

The main commercially used birefringent oxides α-BaB2 O4 and YVO4 have the birefringences of 0.12 and 0.22. We propose a targeted high-throughput screening system to search birefringence-active functional modules (FMs) and large birefringent materials. A series of π-conjugated C-O units [C2 O4 ]2- , [C2 O6 ]2- , [C4 O4 ]2- , and [C6 O6 ]2- are discovered to be birefringence-active FMs. Theoretical and experimental studies on the crystals with C-O units confirm the feasibility of strategy. Based on this, the C-O containing compounds ranging from deep-ultraviolet to near-infrared region with large birefringence from 0.1 to 1.35 are found, and most of them break through the birefringent limit of oxides. The (NH4 )2 C2 O4 ⋅H2 O crystal is grown and its experimental birefringence is 0.248 at 546 nm, which is identified as a promising UV birefringent crystal. The A-site cations play significant roles in optical properties by influencing the density and arrangement of the C-O units.

Anion-coordination-driven assembly (ACDA) is showing increasing power in the construction of anionic supramolecular architectures. Herein, by expanding the anion centers from oxoanion (phosphate or sulfate) to organic tris-carboxylates, an Archimedean solid (truncated tetrahedron) and a highly entangled, double-walled tetrahedron featuring a ravel topology have been assembled with tris-bis(urea) ligands. The results demonstrate the promising ability of tris-carboxylates as new anion coordination "centers" in constructing novel topologies with increasing complexity and diversity compared to phosphate or sulfate ions on account of the modifiable size and easy functionalization character of these organic anions.

Supramolecular cages have been constructed by anion-coordination-driven assembly (ACDA) in recent years and have shown unique host-guest interactions. However, most of the reported cages are made of the phosphate ion (PO43- ); other anions have rarely been explored. Here we show for the first time that the sulfate ion (SO42- ) is also able to form the A4 L4 tetrahedral motif with tris-bis(urea) ligands, but this is dependent on the stoichiometry of the sulfate ion (in solution). Notably, the sulfate cages display enhanced resistance for both Bronsted (pH as low as 4.3 in acetone containing 15 % water) and Lewis acids (metal complexes) compared to the corresponding phosphate cages, and thus could find applications where an acidic (proton or metals) environment is required.

International audience; Phosphorus incorporation into carbon can greatly modify its chemical, electronic, and thermal stability properties. To date this has been limited to low levels of phosphorus. Now a simple, large‐scale synthesis of carbon–nitrogen–phosphorus (CNP) materials is reported with tunable elemental composition, leading to excellent thermal stability to oxidation and fire‐retardant properties. The synthesis consists of using monomers that are liquid at high temperatures as the reaction precursors. The molten‐state stage leads to good monomer miscibility and enhanced reactivity at high temperatures and formation of CNP materials with up to 32 wt % phosphorus incorporation. The CNP composition and fire‐retardant properties can be tuned by modifying the starting monomers ratio and the final calcination temperature. The CNP materials demonstrate great resistance to oxidation and excellent fire‐retardant properties, with up to 90 % of the materials preserved upon heating to 800 °C in air.

Understanding and exploring the functional modules (FMs) consisting of local atomic groups can promote the development of the materials with functional performances. Oxygen‐containing tetrahedral modules are popular in deep‐ultraviolet (DUV) optical materials, but their weak optical anisotropy is adverse to birefringence. Here, the fluorooxosulfate group is proved as a new birefringence‐enhanced FM for the first time. The birefringence of fluorooxosulfates can be 4.8–15.5 times that of sulfates with the same metal cations while maintaining a DUV band gap. The polarizing microscope measurement confirms the birefringence enhancement by using the millimeter crystals experimentally. The theoretical studies from micro and macro levels further reveal a novel universal strategy that the fluorine induced anisotropic electronic distribution in fluorooxo–tetrahedral group is responsible for the enhancement of birefringence. This study will guide the future discovery of DUV optical materials with enlarged birefringence., A novel design and synthesis strategy for birefringent materials. The fluorooxosulfate group is proved as a new birefringence‐enhanced FM for the first time. The fluorine‐free tetrahedra substituted by the fluorooxo‐tetrahedral group can enhance birefringence while maintaining short cut‐off edge, which is proved by the experiments. This study provides a feasible way to design DUV optical materials with enlarged birefringence.

In this study, we monitored the thiol–disulfide redox potential of different Escherichia coli strains using redox-sensitive variants of green fluorescent protein. The cells with extreme oxidizing cytoplasm were generated by introducing a highly efficient disulfide relay system. The developed cells have exceptionally efficient de novo disulfide bond formation and significantly improve the oxidative folding of the client multi-disulfide proteins. Superoxidizing E. coli strain provides an effective method for the high-level production of recombinant disulfide-containing proteins. Biotechnol. Bioeng. 2014;111: 2520–2527. © 2014 Wiley Periodicals, Inc.

Flexible Zn-air batteries have recently emerged as one of the key energy storage systems of wearable/portable electronic devices, drawing enormous attention due to the high theoretical energy density, flat working voltage, low cost, and excellent safety. However, the majority of the previously reported flexible Zn-air batteries encounter problems such as sluggish oxygen reaction kinetics, inferior long-term durability, and poor flexibility induced by the rigid nature of the air cathode, all of which severely hinder their practical applications. Herein, a defect-enriched nitrogen doped-graphene quantum dots (N-GQDs) engineered 3D NiCo2 S4 nanoarray is developed by a facile chemical sulfuration and subsequent electrophoretic deposition process. The as-fabricated N-GQDs/NiCo2 S4 nanoarray grown on carbon cloth as a flexible air cathode exhibits superior electrocatalytic activities toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), outstanding cycle stability (200 h at 20 mA cm-2 ), and excellent mechanical flexibility (without observable decay under various bending angles). These impressive enhancements in electrocatalytic performance are mainly attributed to bifunctional active sites within the N-GQDs/NiCo2 S4 catalyst and synergistic coupling effects between N-GQDs and NiCo2 S4 . Density functional theory analysis further reveals that stronger OOH* dissociation adsorption at the interface between N-GQDs and NiCo2 S4 lowers the overpotential of both ORR and OER.

Two multimode Hg(II) sensors, L-MethBQA and L-CysBQA, were obtained by fusing methionine or S-methyl cysteine, into a bis-quinolyl amine-based chiral podand scaffold. Quinolyl groups serve as the fluorophore and possess nitrogen lone pairs capable of chelating metal ions. On exposure to Hg(2+) or Zn(2+), these sensors show signal enhancement in fluorescence. However, Cu(2+) quenches their fluorescence in 30:70 acetontrile/water. L-CysBQA complexes with Hg(2+), producing an exciton-coupled circular dichroism spectrum with the opposite sign to the one that is produced by Cu(2+) or Zn(2+) complexation. L-CysBQA binds Hg(2+) more strongly than Zn(2+) and is shown to differentiate Hg(2+) from other metal ions, such as Zn(2+), Cu(2+), Ni(2+), and Pb(2+), exceptionally well. The synergistic use of relatively soft sulfur, quinoline-based chiral ligands and chiroptically enhanced fluorescence detection results in high sensitivity and selectivity for Hg(2+).