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Event detection is an important task in the field of natural language processing, which aims to detect trigger words in a sentence and classify them into specific event types. Event detection tasks suffer from data sparsity and event instances imbalance problems in small-scale datasets. For this reason, the correlation information of event types can be used to alleviate the above problems. In this paper, we design a Hierarchical Attention Neural Network for Event Types (HANN-ET). Specifically, we select Long Short-Term Memory (LSTM) as the semantic encoder and utilize dynamic multi-pooling and the Graph Attention Network (GAT) to enrich the sentence feature. Meanwhile, we build several upper-level event type modules and employ a weighted attention aggregation mechanism to integrate these modules to obtain the correlation event type information. Each upper-level module is completed by a Neural Module Network (NMNs), event types within the same upper-level module can share information, and an attention aggregation mechanism can provide effective bias scores for the trigger word classifier. We conduct extensive experiments on the ACE2005 and the MAVEN datasets, and the results show that our approach outperforms previous state-of-the-art methods and achieves the competitive F1 scores of 78.9% on the ACE2005 dataset and 68.8% on the MAVEN dataset. [ABSTRACT FROM AUTHOR]

In‐situ high content N‐doping carbon aerogel (NCA) is successfully prepared via low‐cost m‐phenylenediamine and formaldehyde reaction through the facile sol‐gel method and further high‐temperature carbonization process. NCA material with nanospheres presents the characteristics of large specific surface area and high loading sulfur owing to the specific cross‐linked framework structure. In addition, the NCA/S cathode with high content of nitrogen can achieve strong adsorption to lithium polysulfides (LiPSs) due to its inherent N active sites, and presents outstanding electrochemical performance. In details, the designed NCA/S electrode demonstrates the first discharge capacity of 1247 mAh g−1 at 0.2 C. Moreover, the NCA/S battery also displays excellent electrochemical stability with low capacity attenuation rate of 0.083 % per cycle within 300 cycles at 0.5 C. The remarkable electrochemical properties are mainly ascribed to intense adsorption of evenly‐distributed nitrogen in the carbon material, effectively preventing polysulfide (PS) escaping from host material, restraining shuttle effect and increasing sulfur utilization. [ABSTRACT FROM AUTHOR]

Heterogeneous macromolecule catalysts have been known as efficient electrocatalysts for CO2 reduction reaction, however, manipulating the activity of heterogeneous molecules via controllable metal electronic structure is still challenging. Herein, different CO2 activated 3D, robust, nitrogen‐doped hollow carbon spheres are synthesized to anchor cobalt phthalocyanine as molecularly dispersed electrocatalysts, where the electron‐withdrawing coeffect of carbon defects and heteroatom N is responsible for tuning the electronic structure of metal center. The optimal electrocatalyst reveals high CO faradaic efficiency (FECO) of 95.68%, turnover frequency of 13.80 s−1, and current density of 16.49 mA cm−2 at an overpotential of 760 mV. The control experiment and DFT calculations unveil that the significant activity is mainly ascribed to the optimal electron‐withdrawing coeffect of carbon defects and pyrrolic N, which reduce the electron density of Co center to facilitate CO2 activated to form *COOH intermediate on Co(I) active sites during electrocatalysis. The 2p‐charge loss of Co is summarized as an activity descriptor, which steers the current density and production rate toward CO. Furthermore, the design strategy can universally fabricate the hybrid MPc catalyst with transitional metal (Ni, Fe) site while a rechargeable Zn–CO2 battery is devised to deliver a maximal power density of 1.02 mW cm−2. [ABSTRACT FROM AUTHOR]

SEM images of c) NiPc@NHCS, and d) NiPc@DNHCS-8, inset: TEM images of NiPc@DNHCS-8. gl The corrected caption is as follows. Tuning the Metal Electronic Structure of Anchored Cobalt Phthalocyanine via Dual-Regulator for Efficient CO2 Electroreduction and Zn-CO2 Batteries One image in B Figure b S38a, one image in inset of B Figure b S38b, and one image in inset of B Figure b S38d in the Supporting Information were misplaced. [Extracted from the article]

Cadmium-doped carbon aerogels were successfully prepared via a microtemplate inducing strategy and subsequent high temperature carbonization. The controlled synthesis technology forms spherical carbon aerogels with uniform and interconnected porous structures. The as-prepared materials display large specific surface area and excellent conductivity. The loaded sulfur composites as cathode materials exhibit high discharge capacity and excellent cycling performance. Particularly, the designed P2-Cd-CA/S electrode with 78.9 wt% sulfur presents an initial discharge capacity of 1318 mA h g−1 at 0.2C. And it delivers an initial discharge capacity of 1189 mA h g−1 at 0.5C and still maintains 871 mA h g−1 after 300 cycles. The enhanced performance is mainly ascribed to the synergistic effect of the inductive graphitization of a microtemplate (3,4,9,10-perylenetetracarboxylic dianhydride) and the stronger anchoring for polysulfides of evenly distributed cadmium. Furthermore, the first-principles theoretical calculations further support the strong adsorption between CdO and polysulfides and affirmatively reveal the immobilizing mechanism. [ABSTRACT FROM AUTHOR]

A cage‐type composite was successfully prepared by attaching p‐sulfonatocalix[4]arene to a porous activated carbon aerogel (ACA). The resulting composite showed a high specific surface area of 1620.7 m2 g−1 and a high sulfur loading of 2.5 mg cm−2. The calixarene is uniformly dispersed on the carbon spheres and efficiently captures polysulfides by interaction with the sulfonate groups. Meanwhile, the cross‐linked porous structure of the composite restricts the migration of polysulfides. The cathode delivers an outstanding electrochemical performance with an initial capacity of 1304.7 mAh g−1 at 0.2 C. Furthermore, it displays excellent long‐term cycling stability, maintaining 884.7 mAh g−1 after 300 cycles at 0.5 C. Density functional theory (DFT) adsorption calculations support the strong interaction between the calixarenes and polysulfides and reveal the capture mechanism. [ABSTRACT FROM AUTHOR]

Transparent coatings with antireflection, antifogging, antifrosting, antifouling, and moisture self‐cleaning properties can dramatically improve the efficiency and convenience of optical elements and thus are highly desirable for practical applications. Here, it is demonstrated that a bionic nanocone surface (BNS) fabricated by a facile, low‐cost process consisting of template‐assisted prepolymer curing followed by surface modification can possess the multiple functions listed above. The polymer coating firmly adheres to a glass substrate due to bonding agents. After SiO2 nanoparticle deposition and low‐surface‐energy fluorosilane modification, the coating shows low microdroplet adhesion. As a result, the as‐prepared BNS exhibits a high transmittance when exposed to fog and good clarity even when the temperature decreases to −20 °C in a humid environment. Dipping the BNS into exemplified graphite powder has almost no influence on the transparency, and the BNS can realize self‐cleaning of moisture when the surface is covered with a thick layer of man‐made contaminants. A bionic nanocone array with antireflection, antifogging, antifrosting, antifouling, and moisture self‐cleaning properties is facilely fabricated on a transparent glass by anodic aluminium oxide template‐assisted prepolymer curing followed by silica deposition and low‐surface‐energy fluorosilane modification. The bionic surface shows a high transparency (>95%) after being exposed to a high humidity and low‐temperature or a dirty environment. [ABSTRACT FROM AUTHOR]