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A H2/CO2fuel cell is a promising device that can convert CO2into hydrocarbon fuel with electricity generation. Herein, a facile electrospinning method has been used to synthesize the embedded Ru-CNF catalyst in which Ru nanoparticles are dispersed homogeneously within N-doped carbon nanofibers. This catalyst exhibits a high CH4production rate of 308.46 μmol gcat–1h–1at 170 °C, which is superior to that of the Ru/CNF (242.53 μmol gcat–1h–1) and Ru/CNT (194.24 μmol gcat–1h–1). The enhanced CO2RR performance of Ru-CNF is ascribed to the well-distributed Ru nanoparticles within the CNF matrix and synergistic effect of Ru sites with N species, which results in forming the increased CO2RR active sites, hence improving the catalytic activity. Simultaneously, it can achieve a peak power density of 1.8 W m–2on the strength of anodic (H2oxidation) and cathodic (CO2reduction and H2evolution) reactions with remarkable stability. Such findings give a theoretical basis of CO2RR in the H2/CO2fuel cell system, which could hold great value to further develop the high-efficiency catalysts for CO2reduction.

In this paper, a novel sliding mode fault tolerant control method is presented for aircraft engine systems with uncertainties and disturbances on the basis of adaptive diagnostic observer. By taking both sensors faults and actuators faults into account, the general model of aircraft engine control systems which is subjected to uncertainties and disturbances, is considered. Then, the corresponding augmented dynamic model is established in order to facilitate the fault diagnosis and fault tolerant controller design. Next, a suitable detection observer is designed to detect the faults effectively. Through creating an adaptive diagnostic observer and based on sliding mode strategy, the sliding mode fault tolerant controller is constructed. Robust stabilization is discussed and the closed-loop system can be stabilized robustly. It is also proven that the adaptive diagnostic observer output errors and the estimations of faults converge to a set exponentially, and the converge rate greater than some value which can be adjusted by choosing designable parameters properly. The simulation on a twin-shaft aircraft engine verifies the applicability of the proposed fault tolerant control method.

A cyanide-bridged FeIII2CoIIdouble zigzag chain, {[FeIII(bipy)(CN)4]2CoII(btab)2}n[bipy=2,2′-bipyridine, btab=4,4′-(1,3-phenylene)-bis-4H-1,2,4-triazole] (1), was obtained with tetracyanometalate precursors and CoIIions. The chains were further linked by the ditopic btab ligands to a layer. Magnetic property studies demonstrate that 1shows both metamagnetism with a critical field Hc=400 Oe and single-chain magnet behavior.

Molecules with multifunctional properties are of immense interest in hybrid materials, while challenges still existed because of the limited compatibility of multiple functionalities in a single system. In this work, a series of metal-organic complexes were synthesized and characterized under the assembly of electron donor phosphonate, electron acceptor polypyridine ligand and spin carrier rare earth ions. All the compounds exhibited remarkable and reversible responses with photochromism and photomodulated fluorescence, originated from photogenerated radicals viaelectron transfer from phosphonates to polypyridine ligands. For the Dy analog, slow magnetic relaxation was observed at cryogenic temperature, indicating the single-molecule magnetic behavior. Furthermore, photogenerated radicals could enhance the proton conductive behavior, with about 2 times larger in magnitude after light irradiation for Dy and Y compounds. The introduction of photoluminescence, magnetism and proton conduction into metallic phosphonates can provide potential applications for photochromic materials.

Tuning white-light emission viafree radicals is still a challenge in molecular-based functional materials. Herein, a new photoactive Zn2+oxalate-based chain containing a polypyridine ligand was designed and synthesized with remarkably bifunctional photochromism and photo-actuated greenish white-light emission after UV, sunlight or Xe lamp light irradiation at room temperature. The photo-actuated coloration process was induced by the photogeneration of stable radicals originated from intermolecular electron transfers from oxalate components to the protonated polypyridine units, as demonstrated by UV-vis, IR, electron spin resonance and X-ray photoelectron spectra and magnetic measurements. Importantly, the on/off greenish white light emission (WLE) could be reversibly switched by generation and elimination of radicals vialight irradiation and heat treatment, providing a feasible strategy for designing photoswitchable light emission diodes materials.