Electrocatalytic water splitting is a sustainable way to produce hydrogen energy, but the oxygen evolution reaction (OER) at the anode has sluggish kinetics and low energy conversion efficiency, which is the major bottleneck for large-scale hydrogen production. The design and synthesis of robust and low-cost OER catalysts are crucial for the OER. NiCo-based electrocatalysts have suitable atomic and electronic structures, and show high activity and stability during the OER process. Recently, significant progress has been made in regulating the structure and composition of NiCo-based catalysts and understanding the nature of catalysis, especially the OER mechanism, catalytic active sites, and structure–activity relationship. In this work, we summarized and discussed the latest development of NiCo-based electrocatalysts in the OER, with particular emphasis on catalyst design and synthesis, strategies for boosting OER performance, and understanding the nature of catalysis from experimental and theoretical perspectives. The OER mechanism, some activity descriptors, and atomic and electronic structure–activity relationships based on NiCo-based electrocatalysts are unveiled. Finally, some challenges and futuristic outlooks for improving the performance of NiCo-based electrocatalysts are proposed, and we hope this review can provide guidance for the design of more efficient NiCo-based electrocatalysts.

Energetic materials (explosives, propellants, and pyrotechnics) are used extensively for both civilian and military applications and the development of such materials, particularly in the case of energetic salts, is subject to continuous research efforts all over the world. This Review concerns recent advances in the syntheses, properties, and potential applications of ionic salts based on tetrazole N-oxide. Most of these salts exhibit excellent characteristics and can be classified as a new family of highly energetic materials with increased density and performance, alongside decreased mechanical sensitivity. Additionally, novel tetrazole N-oxide salts are proposed based on a diverse array of functional groups and ions pairs, which may be promising candidates for new energetic materials.

In order to decrease the acidity of the highly explosive 3-nitro-1,2,4-triazol-5-one (NTO), we cocrystallized NTO with a nitrogen-rich weak base compound 5, 6,7,8-tetrahydrotetrazolo[1,5-b] [1,2,4]-triazine (TZTN) in a molar ratio 1 : 1 to form a novel cocrystal explosive. Structure determination showed that the cocrystal is formed by strong intermolecular hydrogen bond interaction. Optical microscopy demonstrated that the crystal morphology of the cocrystal was significantly improved in contrast to the crystal of NTO and TZTN. The differential scanning calorimetry (DSC) showed that the cocrystal exhibited the enhancement of thermal stability and became less sensitive to impact, compared with the TZTN. Moreover, the results suggested that the NTO/TZTN cocrystal not only has unique performance itself, but also effectively alters the properties of NTO and TZTN.crystallographic data in CIF or other electronic format see

This paper deals with the problem of locating a rigid object and estimating its motion in three dimensions. This involves determining the position and orientation of the object at each instant when an image is captured by a camera, and recovering the motion of the object between consecutive frames.In the implementation scheme used here, a sequence of camera images, digitized at the sample instants, is used as the initial input data. Measurements are made of the locations of certain features (e.g., maximum curvature points of an image contour, corners, edges, etc.) on the 2-D images. To measure the feature locations a matching algorithm is used, which produces correspondences between the features in the image and the object.Using the measured feature locations on the image, an algorithm is developed to solve the location and motion problem. The algorithm is an extended Kalman filter modeled for this application.

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Energetic mono- and dicationic 3,4-diaminotriazolium salts have been prepared by combining stoichiometric amounts (1:1 or 2:1 molar ratio) of 3,4-diaminotriazole with various oxygen-containing tetrazoles, and the structures have been confirmed by single-crystal XRD for the first time. All structures are dominated by a strong hydrogen-bond network owing to both amino groups and oxygen in the molecule. All salts, except 7, exhibit excellent thermal stabilities with decomposition temperatures over 200 °C. Based on experimental densities and theoretical calculations carried out by using the Gaussian 03 suite of programs, all salts have calculated detonation pressures (20.3-33.9 GPa) and velocities (7095-8642 m s(-1)).

It is challenging to restore a clear image from an atmospheric degraded sequence. The main reason for the image degradation is geometric distortion and blurring caused by turbulence. In this paper, we present a method to eliminate geometric distortion and blur and to recover a single high-quality image from the degraded sequence images. First, we use optical flow technology to register the sequence images, thereby suppressing the geometric deformation of each frame. Next, sequence images are summed by a temporal filter to obtain a single blurred image. Then, the graph Laplacian matrix is used as the cost function to construct the regularization term. The final clear image and point spread function are obtained by iteratively solving the problem. Experiments show that the method can effectively eliminate the distortion and blur, restore the image details, and significantly improve the image quality.

A series of energetic salts based on 3,4-diamino-1,2,4-triazole with promising detonation performances have been synthesized using a metathesis reaction method or a protonation reaction method.