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In this work, NiCo 2 S 4 , nickel-cobalt layered double hydroxides (NiCo-LDH) and CoS 2 electrodes are successfully prepared by using ZIF-67 as the precursor, the results show that NiCo-LDH and NiCo 2 S 4 are nano-flower-like structures and CoS 2 exhibits a nano-cage structure. The electrochemical properties of the hybrid supercapacitor assembled with NiCo 2 S 4 and activated carbon (AC) as electrodes were tested. As the positive electrode of NiCo 2 S 4 //AC hybrid supercapacitor, the NiCo 2 S 4 electrode has the largest specific capacity of 2934 mAh g−1 at a current density of 1 A g−1. The NiCo 2 S 4 //AC capacitor generates the highest energy density of 38.8 Wh kg−1 when the power density is 993.0 W kg−1 and has a nice cycling performance with a capacity retention rate of 81.2% after 10,000 cycles at 5 A g−1. • Nano-flower-like structures NiCo 2 S 4 is successfully prepared by using ZIF-67 as the precursor. • NiCo 2 S 4 shows nice performance as the cathode of NiCo 2 S 4 //AC (activated carbon) hybrid supercapacitor. • NiCo 2 S 4 //AC (activated carbon) hybrid supercapacitor shows practical potential. [ABSTRACT FROM AUTHOR]

NiCoP/C electrodes with hollow structure are prepared successfully by solvent thermal method and low temperature phosphorylation method, the effect of Co doping on the electrode performance is explored. The hollow sphere structure of NiCoP/C electrode brings out outstanding electrochemical properties. The results of electrochemical tests show that the NiCoP/C electrode delivers a specific capacity of 193.8 mAh g −1 at 1 A g −1 and only losses 6.7% capacity under a 5 A g −1 of current density after 10,000 cycles. In addition, the asymmetric supercapacitor (ASC) device composed of NiCoP/C and activated carbon has an energy density of 53.7 W h kg−1 when the power density is 750 W kg−1. The ASC device is also cycled for 10,000 cycles at a current density of 5 A g −1 while the capacity loss is only 7.2%. [ABSTRACT FROM AUTHOR]

In computed tomography (CT) image reconstruction, the iterative algorithms have many advantages that the analytic algorithms don't have. However, the calculation of system matrix is time-consuming, which affects their application in real-time CT image reconstruction. In this paper, a fast system matrix calculation method is proposed on the basis of that the distance between the voxel and the adjacent rays reflects the contribution of the voxel to the ray projections. Firstly, every voxel is projected at a projection angle, and then the weighting factor is determined according to the distance between the voxel's projection and the adjacent ray projection on the detector. Finally, the ray equations and weighting factors corresponding to every voxel at all projection angles are obtained. The calculation amount of the proposed method are greatly improved compared with the current grid traversal (GT) method, and it has good parallel computing performance. In the simulation experiment, the Shepp-Logan head phantom is reconstructed by using the proposed system matrix calculation method and algebraic reconstruction technique (ART). Compared with GT method, its cost is reduced by nearly 30 %, and its acceleration ratio is four times that of the GT method. The experimental results show that it is a fast and effective method to calculate the system matrix. [ABSTRACT FROM AUTHOR]

The concentrations of the heavy metals Cu, Pb, Zn, As, Cr, Co, and Ni of a total of 187 surface sediment samples collected from the western Taiwan Strait were analyzed. The distribution characteristics and degree of contamination of these elements were investigated. The mean concentrations of Cu, Pb, Zn, As, Cr, Co, and Ni in the surface sediments of the study area were 10.2 mg/kg, 18.3 mg/kg, 51.7 mg/kg, 7.5 mg/kg, 38.7 mg/kg, 8.0 mg/kg, and 16.5 mg/kg, respectively. The heavy metals in the study area were mainly from natural sources. The regional pollution load index (PLIzone) was 0.64, indicating that there was no contamination, and an area with a relatively high PLIzone was found in the northern part of the study area. Furthermore, the impacts of the rapid development of Fujian's marine economy on the marine environment in the past decade should be further compared and analyzed. • The concentrations of the heavy metals were analyzed on the western Taiwan Strait. • The distribution characteristics and degree of contamination were investigated. • The regional pollution load index indicated that there was no contamination. • Relatively high PLIzone was found in the northern part of the study area. • The contamination of the northern area should be continuously monitored. [ABSTRACT FROM AUTHOR]

In order to make use of the advantages of optical computing and promote the application and popularization of Ternary Optical Computer (TOC), this paper proposes a new computing-data model, presents the corresponding computing-data file in detail, and gives the implementation method of programming application with the model files. It tries to set up a bridge between users and TOC. Experimental results show that the model presented in this paper is correct and the implementation method is feasible. The model can better simplify TOC’s application process, and allow users to apply TOC to carry out various computational applications without needing to understand any details of optical implementation. [ABSTRACT FROM AUTHOR]

In order to study multiaxial fatigue behavior of 2024-T4 aluminum alloy with an aircraft in-service environment, fatigue tests of multiaxial pre-corrosion and alternate corrosion are carried out. With the extension of pre-corrosion time, the multiaxial fatigue life decreases under the same equivalent stress. Pitting caused by corrosion is observed on the surface of specimens. While pre-corrosion time increases, the number and size of pits become larger and connection between adjacent corrosion pits becomes more obvious. For the multiaxial fatigue tests with alternate corrosion, for the same unit corrosion time, the fatigue life decreases with the increase of unit loading cycles. Under the same unit loading cycles, the fatigue life decreases as the unit corrosion time increases. The cyclic hardening appears in both axial and tangential directions at the initial loading stage. Cyclic softening trend becomes obvious as the number of alternation increases. It is shown that cracks initiate at specimen surface and gradually extend to inside. Exfoliation corrosion morphology can be observed on specimen surface. Based on Miner’s rule and data of pre-corroded multiaxial fatigue test, the alternate corrosion-multiaxial fatigue lives are predicted. [ABSTRACT FROM AUTHOR]

Principal component analysis (PCA) is a widely used algorithm in the field of artificial intelligence and statistical analysis. When dealing with a large number of high-dimensional data, the traditional PCA algorithm has some shortcomings, such as slow processing speed, high power consumption, low computational efficiency. By taking advantage of several characteristics which include large number of data bits, easy-expansion of data bits, and parallel computing in ternary optical computer (TOC), the implementation scheme of parallel PCA algorithm is studied. Through the analysis of the traditional PCA algorithm, the parallel parts are found out and parallel design is carried out. Then, the elaborate implementation flow of the algorithm is given, and the clock cycle and hardware resources of the algorithm are also analyzed. Finally, the validity of the parallel scheme is proved by experiments. Compared with the traditional PCA algorithm, the PCA algorithm based on TOC has better time performance, operational efficiency, and gives full play to the advantage of ternary optical computer in processing complex computation. [ABSTRACT FROM AUTHOR]