Convolutional Neural Networks-Based Object Detection Algorithm by Jointing Semantic Segmentation for Images.

In recent years, increasing image data comes from various sensors, and object detection plays a vital role in image understanding. For object detection in complex scenes, more detailed information in the image should be obtained to improve the accuracy of detection task. In this paper, we propose an object detection algorithm by jointing semantic segmentation (SSOD) for images. First, we construct a feature extraction network that integrates the hourglass structure network with the attention mechanism layer to extract and fuse multi-scale features to generate high-level features with rich semantic information. Second, the semantic segmentation task is used as an auxiliary task to allow the algorithm to perform multi-task learning. Finally, multi-scale features are used to predict the location and category of the object. The experimental results show that our algorithm substantially enhances object detection performance and consistently outperforms other three comparison algorithms, and the detection speed can reach real-time, which can be used for real-time detection.

CoS nanosheets wrapping on bowl-like hollow carbon spheres with enhanced compact density for sodium-ion batteries.

Transition metal sulfides have long suffered from poor conductivity and large volume change when valued as an anode material for sodium-ion batteries. Hollow carbon nanohybrids prove to be the highly effective materials to solve these problems. While the low inherent compact density of hollow material leads to the low volume energy density of batteries. Herein, we employ a bowl-like hollow carbon sphere as the carbon substrate to promote compact density. Owing to the smaller cavity size and compact arrangement of bowl-like hollow spheres, the well-designed CoS@bowl-like hollow carbon spheres ultimately upgrade the compact density to 122% compare with that of CoS@hollow carbon spheres. Meanwhile, the hierarchical and interconnected CoS nanosheets tightly wrapped on the surface of the spheres, which can not only prevent self-aggregation of CoS but also provide shorter transmission path of both ions and electronics. This novel CoS@bowl-like hollow carbon spheres exhibit a good cycling performance: a reversible capacity of 543 mAh g-1 after 400 cycles and 452 mAh g-1 after 1000 cycles at 1 A g-1. The Na3V2(PO4)3//CoS@ bowl-like hollow carbon spheres full cell shows a reversible capacity of 320 mAh g-1 at 0.5 A g-1.

Transition-Metal Oxides Anchored on Nitrogen-Enriched Carbon Ribbons for High-Performance Pseudocapacitors.

Increasing demand for effective energy-storage systems derived from low-cost and ecofriendly raw materials has aroused wide concern. In this contribution, we propose nitrogen-abundant amorphous micron-sized carbon ribbons (AMCRs) originating from biomass raupo as a novel substrate due to their specific quasi 2D morphologies and outstanding dispersion ability. Owing to the innate nitrogen atoms on the surface of AMCRs, ultrathin binary and ternary metal oxide (NiO, CoO, and NiCo2 O4 ) nanosheets can be uniformly developed under benign conditions. These three composites were separately fabricated as electrodes for supercapacitors in a three-electrode system and exhibited favorable activities. Among them, the ternary metal oxide composites NiCo2 O4 @AMCRs delivered the supreme specific capacitance of 1691 F g-1 and best cycling stability (89 % capacity retention over 10,000 cycles). Moreover, symmetric supercapacitors (NiCo2 O4 @AMCRs//NiCo2 O4 @AMCRs) were assembled inside sleeve devices with 2 m KOH aqueous electrolyte, which demonstrated admirable cyclic stability (79.1 % capacity retention over 8,000 cycles), and an excellent energy density of 26 Wh kg-1 at the power density of 1.8 kW kg-1 .

Hierarchical NiCoO2 Nanosheets Anchored on Hollow Carbon Spheres for High-Performance Lithium-Ion Battery Anodes.

This study reports the synthesis of hierarchical NiCoO2 nanosheets growing on hollow carbon spheres (denoted as NiCoO2 NSs@HCS) via a facile and low-cost process. When evaluated as anode materials for lithium-ion batteries, the as-prepared NiCoO2 NSs@HCS exhibits high specific capacity, enhanced cycling stability, and good rate capability. A high discharge capacity of 631.7 mA h g-1 is delivered even after 200 cycles at a current density of 400 mA g-1 , corresponding to approximately 92 % of the second reversible discharge capacity. The hierarchical and hollow structure of NiCoO2 NSs@HCS plays a role in its excellent performance.

Solvothermal-Etching Process Induced Ti-Doped Fe2O3 Thin Film with Low Turn-On Voltage for Water Splitting.

In this work, a thinning process of hematite film accompanied by simultaneous titanium (Ti) doping has been demonstrated. Ti(4+) ion was incorporated into ultrathin Fe2O3 film by solvothermally etching a hematite film fabricated on titanium nanorod array substrate. As a consequence, the onset potential (Von) of oxygen evolution reaction for final ultrathin Ti-doped Fe2O3 film shifted toward cathodic substantially, a very low Von of 0.48 VRHE was realized, approximately 0.53 V cathodic shift of the hematite film. Working mechanisms were investigated from both kinetic and thermodynamic ways. The ultrathin Ti-doped Fe2O3 film exhibited reduced Tafel slope and higher generated photovoltage than the pristine Fe2O3 electrode. Moreover, the highly doped Fe2O3 resulted in significant reduction of charge-transfer resistance at the Fe2O3∥electrolyte interface. The drastic cathodic-shift Von is believed to be a result of combined factors including thermodynamic contribution, improved surface reaction kinetics, as well as facilitated charge transfer across bulk and interface.

Observation of allylic rearrangement in water-rich reaction.

Allylic rearrangement or the migration of a double bond from its original position in the carbon skeleton to an adjacent site was observed when 3,4,5,6-tetrahydrophthalate was hydrolyzed in a basic solution and in the presence of Co(ii) and Mn(ii) under hydrothermal conditions.