Unravelling the pseudocapacitive origin of graphene oxide-based aerogels by comparative insights.

We reveal the intrinsic pseudocapacitive center of graphene-oxide-based aerogels by investigating different modified graphene skeletons from various approaches. A high proportion of carbonyl groups in carbon networks is shown to optimize the construction of rational pseudocapacitive sites by triggering reversible proton-induced surface reactions, leading to satisfactory electrochemical performance.

Autonomous Identification and Positioning of Trucks during Collaborative Forage Harvesting.

In the process of collaborative operation, the unloading automation of the forage harvester is of great significance to improve harvesting efficiency and reduce labor intensity. However, non-standard transport trucks and unstructured field environments make it extremely difficult to identify and properly position loading containers. In this paper, a global model with three coordinate systems is established to describe a collaborative harvesting system. Then, a method based on depth perception is proposed to dynamically identify and position the truck container, including data preprocessing, point cloud pose transformation based on the singular value decomposition (SVD) algorithm, segmentation and projection of the upper edge, edge lines extraction and corner points positioning based on the Random Sample Consensus (RANSAC) algorithm, and fusion and visualization of results on the depth image. Finally, the effectiveness of the proposed method has been verified by field experiments with different trucks. The results demonstrated that the identification accuracy of the container region is about 90%, and the absolute error of center point positioning is less than 100 mm. The proposed method is robust to containers with different appearances and provided a methodological reference for dynamic identification and positioning of containers in forage harvesting.

Facile Synthesis of Monodispersed Ag NPs in Ethylene Glycol Using Mixed Capping Agents.

Capping agents play an important role in the synthesis of silver nanostructures in polyol solvents. In this work, we demonstrate that using a small amount of tannic acid (TA), a reducing capping agent, in addition to poly(vinylpyrrolidone) (PVP), a protective capping agent, can lead to the production of monodisperse spherical silver nanoparticles (Ag NPs) that are stable with respect to particle aggregation for at least 100 days and have particle sizes ranging from 16 to 28 nm depending on the TA concentration. We hypothesize that the complexation between PVP and TA can lead to the formation of a stable particle coating and a fast Ag+ reduction rate at a relatively high TA concentration. Both effects can benefit the formation of small spherical Ag NPs with narrow size distribution.

Potentiometric in Situ Monitoring of Anions in the Synthesis of Copper and Silver Nanoparticles Using the Polyol Process.

Potentiometric sensors, such as polymeric membrane, ion-selective electrodes (ISEs), have been used in the past to monitor a variety of chemical processes. However, the use of these sensors has traditionally been limited to aqueous solutions and moderate temperatures. Here we present an ISE with a high-capacity ion-exchange sensing membrane for measurements of nitrate and nitrite in the organic solvent propylene glycol at 150 °C. It is capable of continuously measuring under these conditions for over 180 h. We demonstrate the usefulness of this sensor by in situ monitoring of anion concentrations during the synthesis of copper and silver nanoparticles in propylene glycol using the polyol method. Ion chromatography and a colorimetric method were used to independently confirm anion concentrations measured in situ. In doing so, it was shown that in this reaction the co-ion nitrate is reduced to nitrite.