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Density functional theory-based characterization of crystalline tungsten oxide has been well established. Nonetheless, there remains a partial gap in theoretical studies concerning the electrochemical characterization of amorphous tungsten oxide. The electronic structure and diffusion kinetics of amorphous tungsten oxide require a systematic theoretical study. Therefore, we employed second-generation Car–Parrinello molecular dynamics simulations and the density functional theory with HSE06 exchange–correlation hybrid functional to investigate the electronic properties and lithium kinetics of amorphous tungsten oxide (α-WOx, x = 3, 2.5, 2) models. The precise electronic properties of these structures were computed using the HSE06 hybrid functions. The diffusion properties of lithium were determined in the range of 1 × 10−7 to 5 × 10−7 cm2/s by ab initio molecular dynamics. The computational findings provide a critical atomic-scale understanding and contribute to the development of tungsten oxide-based electrochromic devices for practical applications. [ABSTRACT FROM AUTHOR]

Light field cameras are unsuitable for further acquisition of high-quality images due to their small depth of field, insufficient spatial resolution, and poor imaging quality. To address these issues, we proposed a novel four-focal-square microlens and light field system. A square aspheric microlens array with four orthogonal focal lengths was designed, in which the aperture of a single lens was 100 μm. The square arrangement improves pixel utilization, the four focal lengths increase the depth of field, and the aspheric improves image quality. The simulations demonstrate pixel utilization rates exceeding 90%, depth-of-field ranges 6.57 times that of a single focal length, and image quality is significantly improved. We have provided a potential solution for improving the depth of field and image quality of the light field imaging system. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicle remote sensing image matching techniques are crucial for urban planning and environmental monitoring. However, existing feature matching methods have limitations due to the lack of effective extraction of key diverse features, which hinders the improvement of matching accuracy for diverse ground scenes. To address the above limitations, we propose a remote sensing image feature-matching method using optimally regularized nonlinear diffusion model. Specifically, we first use the accelerated-KAZE (AKAZE) algorithm framework to detect and characterize features within a nonlinear scale space. To improve the adaptation of diffusion to the local image structure, we propose the introduction of a novel Charbonnier regularized nonlinear diffusion model for constructing the diffusion coefficients. We then propose to combine Brute force with the K -nearest neighbor algorithm to eliminate invalid matches. Lastly, we modified the sampling approach of the random sample consensus (RANSAC) algorithm. Instead, we achieve iterative dataset purification using the progressive sample consensus algorithm, complemented by the implementation of a termination criterion for the sampling process. Experimental results show that our method achieves an average matching precision of 82.8%, 80.2%, 82.9%, and 91.2% when the test set undergoes scale, rotation angle, noise blurring, and luminance variations, respectively, outperforming the existing feature matching methods. [ABSTRACT FROM AUTHOR]

This paper proposes that Ca2+ in steel slag (SS) has a weak early hydration activity when SS and granulated blast-furnace slag (GBFS) are used as alkali-activated cementitious materials. Herein, alkaline activators and Ca(OH)2 are used as indicators of Ca2+ reaction in the SS and GBFS system. It is found that the 28-day compressive strength of the cementitious material with 2 wt% Ca(OH)2 addition increased by 25.9% compared with the blank. Hydration products and microstructures were characterized by XRD, SEM/EDS, FTIR and TG/DTA. Results show that the addition of Ca(OH)2 increased the content of active calcium ions in the reaction system, which promotes the reaction and the formation of C–S–H gel, resulting in an enhanced compressive strength ultimately. It can be also concluded that SS is not suitable as a sole precursor for the production of building materials on a large scale due to the weak early activity of Ca2+ in SS. [ABSTRACT FROM AUTHOR]

To study the deterioration law of mechanical properties of glass fiber reinforced composite (GFRP) bars in an alkaline solution, tensile tests were carried out using 20 mm and 25 mm GFRP bars for 30 days, 90 days and 180 days to obtain the mechanical properties such as ultimate tensile strength and elastic modulus after different corrosion time in the alkaline solution were obtained. Meanwhile, a comparative study on the mechanical properties of GFRP bars with the same diameters was conducted in saline solution for 180 days. The residual tensile strength degradation model was established for the GFRP bars in the alkaline solution. The results indicated that the deterioration degree of mechanical properties of GFRP bars in the alkaline solution was worse than that in the saline solution at the same corrosion age. The tensile strength of GFRP bars tended to decrease with an increase of soaking time in the alkaline solution, and their corrosion rate in the early stage was faster than that in the later stage. The modified residual strength degradation model of GFRP bars was in a good agreement with the test results. [ABSTRACT FROM AUTHOR]

Preparation of LiCoO2 cathode materials from spent lithium–ion batteries are presented. It started with the reclaim/recycle of metal values from spent lithium–ion batteries, which involves the separation of electrode materials by ultrasonic treatment, acid dissolution, precipitation of cobalt and lithium, followed by the preparation of LiCoO2 cathode materials. Co (99.4%) and Li (94.5%) were recovered from spent lithium–ion batteries. The LiCoO2 cathode materials prepared from the reclaimed cobalt and lithium compounds showed good elecrtochemical performance. The reclaiming of cobalt and lithium has a promising outlook for the recycling of cobalt and lithium from spent Li–ion batteries, thus reducing the cost of Li–ion batteries. [ABSTRACT FROM AUTHOR]