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An efficient access to a large array of diarylmethane thioether derivatives is developed through catalyst‐free 1,6‐conjugate addition of 1,4‐dithiane‐2,5‐diols with para‐quinone methides in high to excellent yields. Moreover, this reaction system is also suitable for other sulfur‐based nucleophiles, and the resulting products can be readily converted into other valuable diarylmethane derivatives. [ABSTRACT FROM AUTHOR]

Exploration of optoelectronic memristors with the capability to combine sensing and processing functions is required to promote development of efficient neuromorphic vision. In this work, the authors develop a plasmonic optoelectronic memristor that relies on the effects of localized surface plasmon resonance (LSPR) and optical excitation in an Ag–TiO2 nanocomposite film. Fully light‐induced synaptic plasticity (e.g., potentiation and depression) under visible and ultraviolet light stimulations is demonstrated, which enables the functional combination of visual sensing and low‐level image pre‐processing (including contrast enhancement and noise reduction) in a single device. Furthermore, the light‐gated and electrically‐driven synaptic plasticity can be performed in the same device, in which the spike‐timing‐dependent plasticity (STDP) learning functions can be reversibly modulated by visible and ultraviolet light illuminations. Thereby, the high‐level image processing function, i.e., image recognition, can also be performed in this memristor, whose recognition rate and accuracy are obviously enhanced as a result of image pre‐processing and light‐gated STDP enhancement. Experimental analysis shows that the memristive switching mechanism under optical stimulation can be attributed to the oxidation/reduction of Ag nanoparticles due to the effects of LSPR and optical excitation. The authors' work proposes a new type of plasmonic optoelectronic memristor with fully light‐modulated capability that may promote the future development of efficient neuromorphic vision. [ABSTRACT FROM AUTHOR]

The no‐reference image quality assessment (NR‐IQA) method can evaluate the distortions in an image without the reference image. However, due to the diversity of the image contents and distortion types, it is hard for the existing NR‐IQA algorithms to obtain competitive performance on both synthetically and authentically distorted images. To address the problem, a multiscale feature representation‐based NR‐IQA method that performs well for both synthetic and authentic distortions is proposed. This model consists of two parts: The feature extraction part and the feature fusion part. First, part of the Res2Net‐50 network is chosen as the feature extraction part due to its high ability in increasing the range of receptive fields. Then, the feature fusion part consisting of a novel residual block and two fully connected layers is designed to fuse the extracted features and realize the quality score mapping. After a series of stepwise optimization experiments, the most competitive network architecture consisting of the feature extraction part and the feature fusion part is obtained. Comprehensive experiments on the LIVE, TID2013, CSIQ, KADID‐10k, KonIQ‐10K, and LIVE challenge databases demonstrate that the proposed method can work powerfully on both the synthetic and authentic distortions and also has a strong generalization ability. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) network thin film field‐effect transistors (TFTs), which used to be considered as low cost and low performance transistors for display driving or flexible electronics, have recently been used to construct digital integrated circuits (ICs). However, few studies have focused on exploring how optimal CNT TFTs can be achieved according to transistor standards in digital applications. In this work, sub‐micrometer TFTs based on high‐quality and high‐purity solution‐derived CNT films are fabricated and the potential performance restriction due to the switching‐off property of these transistors is explored. Specifically, subthreshold swing (SS) severely degrades upon scaling down the channel length or increasing the CNT density in TFTs, and a tradeoff between peak transconductance (gm) and SS in CNT TFTs due to the random orientation distribution of CNTs has been observed in experiments and proven by theoretical simulations. A well‐designed balance between gm and SS is necessary to build CNT TFTs with SS of 120 mV dec−1 and gm of 150 µS µm−1 to meet device requirements in digital ICs powered by a supplied voltage, VDD, lower than 2.0 V. [ABSTRACT FROM AUTHOR]