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A new efficient homocoupling reaction was reported in one pot by a combination of metallic magnesium and a catalytic amount of manganese (II) chloride. Various aromatic and alkyl halides underwent homocoupling smoothly, affording the corresponding symmetrical homocoupling compounds in moderate to good yields. The readily available MnCl 2 , the mild reaction conditions and the operational simplicity and practicability allow for an easy and practical procedure for the purpose of carbon-carbon bond formation.

The optical properties and performance of the two-dimensional photonic crystal (2D PhC) filters at normal incidence were simulated, and the best geometric parameters were obtained with the help of a global optimization program. The honeycomb structure has better performance, including high in-band transmittance, high out-band reflectance, and low parasitic absorption. The power density performance and conversion efficiency can reach 80.6% and 62.5%. Furthermore, the deeper cavity structure and multi-layer structure were designed to improve the performance of the filter. The deeper one can reduce the influence of transmission diffraction, increases the power density performance and conversion efficiency. The multi-layer structure reduces the parasitic absorption significantly and increases the conversion efficiency to 65.5%. These filters have both high efficiency and high power density, avoid the challenge of high-temperature stability faced by emitters, also easier and cheaper to fabricate compared to the 2D PhC emitters. These results suggest that the 2D PhC filters can be used in thermophotovoltaic systems for long-duration missions to improve the conversion efficiency.

The ionic rectification effect, an important phenomenon existing in the solid-state nanopore system, has attracted much attention due to its ability to significantly regulate ion transport in the nanopores. However, current research mainly focuses on the single nanopore systems with low ionic currents, and thus further practical applications are limited. In this work, the conical nanoporous polyimide (CNPI) membrane was prepared by ion irradiation and asymmetric chemical etching to increase the ionic current, and the graphene oxide membrane (GOM) was spincoated on it to improve the corresponding ionic flux and rectification effect after that. It was found that the ionic rectification ratio (0.05 M KCl at 3 V) increased from 17 (CNPI membrane) to 63 (GOM/CNPI composite) with the ionic current in microamperes. The enhanced rectification effect was ascribed to the increased geometry asymmetry and charge asymmetry, which further increased the difference of ionic conductance at opposite bias. Moreover, the corresponding COMSOL simulation revealed that the enhanced ion depletion and enrichment appeared in the nanochannel, especially at the tip side of conical nanopores after the GOM was spin-coated on the CNPI membrane. Finally, it was also confirmed that the GOM/CNPI composite can exhibit a good rectification effect and chemical durability in a wide acidic condition (pH 1 to 6), which extends the practical applications of the conical nanopore in a nanofluidic system.

Polyphenyl derivatives Q 0700 Efficient Homocoupling Reactions of Halide Compounds Catalyzed by Manganese (II) Chloride. -Bromides are found to be the best substrates in the reaction which tolerates various functional groups. -(YUAN*, Y.; BIAN, Y.; Appl.