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Three methods for repairing spent graphite and an exploration of impurities-catalyzing effect related to spent graphite regeneration are presented. Relative economy, environment, and performance are investigated in detail.

The application of Mg alloys is always accompanied by various coating technology, but a reliable model predicting the service life of coatings on Mg alloys is lacking but urgent. In this work, a semi-mechanistic model was proposed to predict the service life of plasma electrolytic oxidation (PEO) coating/electrophoretic coatings on a VW63Z Mg alloy; the model was decomposed into three parts: a first part depicting the degradation time of organic coating (L1) and the diffusion time of electrolyte in the inorganic coating (L2), respectively; a second part interpreting the breakdown of coatings due to the corrosion process (L3); a final part establishing an algorithm converting the accelerated tests into the real service environment (α); the effect of structural stress and dissimilar metal joints on the service life of coatings was also considered. Based on the ongoing accelerated experiments, the semi-mechanistic model could be able to predict the service life of both PEO coatings and composite coatings on VW63Z Mg alloy with a satisfiable precision.

Tailoring controllable pores types, diameter size and heteroatom doping on hollow carbon spheres to obtaining the suitable carbon-hosting, which found that of Se-loading content was up to 58% by using vapor-infiltration method, achieved a high initial capacity of 652 mA h g−1at 0.1 C and an astonish long-cycling ability of 224.9 mA h g−1at 5 C after 6,000 loops.

AC impedance response is an important criteria in characterizing the electrochemical performance of metal ion batteries, including sodium ion batteries (SIBs) and lithium ion batteries (LIBs). This work investigates the electrochemical impedance spectroscopy (EIS) of diffusion-controlled intercalation in LIBs and surface-redox charge storage in SIBs. To do so, a first-principle based physical modeling was performed for a nanoparticle of TiO2immersed in lithium ion or sodium ion electrolytes. Nyquist plots showed typical charge transfer resistance, diffusion impedance, and capacitive behaviors for lithium ion storage. The diffusion impedance was absent for sodium ion storage. Similarly, the radial distribution of ion concentration response showed significant slope jump for lithium ion storage, also absent for sodium ion storage. In addition, the charge transfer resistance first remained constant then increased with the increase in bias potential for both lithium ion storage and sodium ion storage, both numerically and experimentally. This corresponded to the Faradaic and capacitive regimes in the CV curves. Furthermore, distribution of relaxation time (DRT) analysis showed two distinct peaks, corresponding to the charge transfer process and the diffusion process. Finally, the resistances of lithium ion storage increased with the increase in electrode nanoparticle diameter, due to the increase in diffusion pathways. On the other hand, sodium ion intercalation was independent of the size of the electrode nanoparticle. This investigation offered insights in distinguishing extrinsic pseudocapacitance from intrinsic pseudocapacitance through EIS analysis.

Owing to its fascinating properties (such as high theoretical specific capacity and considerable conductivity), nickel sulfide (NiS) was investigated comprehensively as an anode material in sodium-ion batteries. However, they still suffered from volume expansion and sluggish kinetics, resulting in serious cycle capabilities. Herein, through controlling the kind of molten salts (Na2SO4, NaCl, and Na2CO3) in salt melt synthesis (SMS), a series of NiS with an N, S-codoped carbon layer was successfully prepared, accompanied with different morphologies and structures (earthworm-like belts and triangular and spherical particles). Tailored by the ionic strength and viscosity of molten salts, the as-prepared samples displayed different crystallization behaviors, bringing about a difference in electrochemical performance. As earthworm-like NiS@C was explored as an anode material for SIBs, an initial capacity of 712.5 mAh g–1at 0.5 A g–1could be obtained, and it still kept 527.4 mAh g–1after 100 cycles. Even at 2.0 A g–1, a capacity of 508.6 mAh g–1could be achieved. Meanwhile, with the assistance of detailed kinetic analysis, the rapid diffusion behaviors of Na+and redox reaction mechanisms of as-fabricated samples were proven for the enhanced electrochemical properties. Given this, this work is expected to provide a method for designing the morphology and structure of metal sulfides, while shedding light on the orientation of fabricating advanced electrode materials for SIBs.

Magnetostrictive alloys have attracted increasing attention in biomedical applications because of the ability to generate reversible deformation in the presence of external magnetic fields. This review focuses on the advances in magnetostrictive alloys and their biomedical applications. The theories of magnetostriction are systematically summarized. The different types of magnetostrictive alloys and their preparation methods are also reviewed in detail. The magnetostrictive strains and phase compositions of typical magnetostrictive alloys, including iron based, rare-earth based and ferrite materials, are presented. Besides, a variety of approaches to preparing rods, blocks and films of magnetostriction materials, as well as the corresponding methods and setups for magnetostriction measurement, are summarized and discussed. Moreover, the interactions between magnetostrictive alloys and cells are analyzed and emphasis is placed on the transduction and transformation process of mechanochemical signals induced by magnetostriction. The latest applications of magnetostrictive alloys in remote microactuators, magnetic field sensors, wireless implantable devices and biodegradable implants are also reviewed. Furthermore, future research directions of magnetostrictive alloys are prospected with focus on their potential applications in remote cell actuation and bone repair.

The construction of a smart city puts forward new requirements for lighting systems, such as variable color temperature adapting to environment and low energy consumption. We introduce a variable color temperature laser lighting system that produces uniform light with minimum energy. The color temperature is controlled by tri-color RGB diode lasers, and uniform lighting is achieved by microlens arrays. Tri-color diode lasers with wavelengths of 650, 556, and 450 nm are used as the lighting sources, and the white light laser output is achieved by combining the three beams. The color temperature is controlled by changing the power ratio of each lighting source. Finally, the homogenization of laser energy is regulated by the microlens arrays, and the energy uniformity reaches 91.1%. Moreover, we do an experiment to compare LED street lighting and laser street lighting, finding that the street lighting system with this design can increase the energy utilization rate by 113.33%, and the color temperature of the car headlamps with this design can be changed according to the environment. Therefore, this laser lighting system is an effective solution for modern smart lighting systems and energy saving, which have vast application.

Grass carp (Ctenopharyngodon idellus, C.idellus) is one of the most important globally cultured freshwater fish species, and its growth trait can be improved by dietary supplementation of oligopeptides which is transported through the intestinal oligopeptide transporter PepT1. However, many aspects of the molecular regulation mechanism of C.idellusPepT1 still remains elusive. In this study, the regulation mechanism of C.idellusPepT1 by CDX2 was extensively studied. Firstly, the interaction of the C.idellusCDX2 and SP1 was investigated by mammalian two hybrid assays and co-localization; The promoter sequence of PepT1 was cloned and its activity was directly up-regualted by CDX2. In the further study, the effect of CDX2 changes at both mRNA and protein levels on the expression of PepT1 was examined in vivo and in vitro. The mRNA expression of PepT1 was significantly decreased when CDX2 was repressed and its expression change profile was almost consistent with that of CDX2. To understand the regulation of CDX2 on the expression of PepT1 at protein level, the stability regulation mechanism of CDX2 was initially studied. The results showed that CDX2 protein was degraded via the ubiquitin-proteasome pathways, and increasing phosphorylation level of CDX2 protein declined its turnover and elevated its accumulation level in cells. The expression of PepT1 was significantly elevated with increasing CDX2 protein stability, and expressions of both CDX2 and PepT1 were stimulated by the oligopeptide. In conclusion, these observations may shed new light on the molecular regulation mechanism of PepT1 by CDX2 in C.idellusand provide new perceptions and strategies for the efficient transportation of intestinal oligopeptides in teleost fish.