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An electron acceptor based on a quinoidal dipyrrolopyrazinedione core was synthesized for organic solar cells and photodetectors. A power conversion efficiency of 6.7% and a specific detectivity of 4.1 × 1013 Jones at 800 nm have been obtained, suggesting the promising prospects of quinoidal molecules for optoelectronic devices. [ABSTRACT FROM AUTHOR]

Early detection of lung cancer is the most promising path to increase the chance of survival for patients. Accurate lung nodule detection in computed tomography (CT) images is a crucial step in diagnosing lung cancer. CNN based CADe systems diagnose lung nodules in two stages by using one network for detection and another following network for classification or false positive reduction. Besides costly construction, two-stage systems can only find a single-scale location including many surrounding contexts for each nodule, which leads to a limited accuracy when classifying small nodules. In this paper, we construct a one-stage framework relying on feature pyramid network (FPN) for the diagnosis of lung adenocarcinoma (LA). The proposed network has two advantages, (i) it can localize and classify LAs simultaneously. (ii) it generates feature maps with high resolution, from which robust classification is reached since tight coverage takes less contextual information. The performance of the proposed one-stage diagnostic network is verified on a lung adenocarcinoma dataset. Experimental results show that it achieves higher sensitives than two-stage frameworks. [ABSTRACT FROM AUTHOR]

Enhancing the selectivity of light olefin intermediates is crucial for efficiently synthesizing aromatic hydrocarbons from CO 2 hydrogenation. However, due to the limitations of Anderson-Schulz-Flory law, the oriented synthesis of light olefins over Fe-based catalysts is challenging. Herein, we creatively insert Y zeolite between the Fe-based catalyst and ZSM-5 zeolite to form a sandwich configuration. The excellent cracking function of sandwich Y zeolite enables the products before the aromatization to be concentrated in the light unsaturated hydrocarbons, leading to a high aromatic selectivity during the succedent aromatization processes. With the assistance of Y zeolite, the light olefin selectivity of the K-Fe catalyst increases from 30.8 % to 40.3 %. After combining with ZSM-5 zeolite, the aromatic selectivity of the ternary system is boosted from 27.6 % to 51.5 % compared to the bifunctional catalysts without Y zeolite. Our studies offer insightful guidance for the rational utilization of multifunctional zeolites to directly synthesize target products. [Display omitted] • The ternary system with sandwich configuration markedly facilitates the synthesis of aromatics. • The introduction of Y zeolite increases the light olefin selectivity from 30.8 % to 40.3 %. • Aromatic selectivity is promoted from 27.6 % to 51.5 % with the sandwich configuration. [ABSTRACT FROM AUTHOR]

Appropriate amount of K effectively balances the existence of non-dissociative CO*, HCOO* intermediates and CH x * intermediates, thereby promoting the CH x -CO coupling in ethanol production from syngas. [Display omitted] • K modulated the distribution of adsorbed CO*, CH x * and HCOO* intermediates. • The 1K-CuCo nanosheets exhibited excellent ethanol selectivity. • Abundant adsorption of strongly bound formate species enhanced CH x * intermediates. • Optimal K dose balanced non-dissociative and dissociative CO species effectively. A set of K-promoted CuCoAl nanoplates were synthesized via precipitation followed by impregnation method and assessed for syngas conversion. The optimized 1K-CuCo catalyst manifested a relatively higher total alcohols selectivity of 48.4 %, with ethanol comprising 35.4 % of total alcohols. As indicated by in situ CO DRIFT and XPS outcomes, on the 1K-CuCo catalyst surface, a distinct preference was observed for the adsorption of CO on Cu+ species (non-dissociative CO*) and bridging CO adsorption on Co species (dissociative CO*). A substantial presence of strongly adsorbed formate species, which contributed favorably to the production of CH x * intermediates, was also identified on the optimal catalyst surface. More importantly, operando DRIFT characterization confirmed that K-modified CuCo catalyst effectively inhibited the hydrogenation (or coupling) of adsorbed CH x * intermediates derived from formate species to generate methane and C 2+ H. Instead, the adsorbed CH x * intermediates coupled with non-dissociated CO* to form CH x CO* species. Therefore, the K promoter can finely regulate the adsorption strength and distribution of intermediates species, thus furnishing sufficient CH x * intermediates and CO* species to take part in CH x -CO coupling reaction to synthesize ethanol. [ABSTRACT FROM AUTHOR]

In recent years, the direct and efficient conversion of CO 2 to light aromatics (BTX: benzene, toluene and xylene) has attracted wide attention. It not only reduces the CO 2 concentration in the atmosphere but also provides a promising non-petroleum technology to produce BTX. Herein, a composite ZrCr-C/ZSM-5 catalyst was developed for CO 2 to BTX. Different with conventional SiO 2 modification method, the HZSM-5 zeolite was modified by amorphous carbon (C) through a facile modified impregnation method. The amorphous C could enter the internal channel of HZSM-5 zeolite and poison partial acid sites. In CO 2 to BTX reaction, after introducing 1.45 wt% C on HZSM-5 zeolite, BTX selectivity increased from 36.2% to 45.4%. In addition, the ZrCr-1.45 C/ZSM-5 catalyst exhibited 46.9% BTX selectivity with 13.5% CO 2 conversion, under 5.0 MPa, 360 °C and 4800 mL/g cat /h. This work not only paves a new strategy to modify HZSM-5 zeolite but also provides an efficient composite catalyst for direct conversion of CO 2 to BTX. [Display omitted] • Direct conversion of CO 2 to light aromatics by a composite ZrCr-C/ZSM-5 catalyst. • The C/ZSM-5 zeolite was prepared by a facile modified impregnation method. • The ZrCr-C/ZSM-5 catalyst exhibited 46.9% BTX selectivity. [ABSTRACT FROM AUTHOR]