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The separation and extraction of associated rare earths from the Zhijin phosphorite mine is of great interest. Based on previous studies, the hydrolysis of phosphate ore using hydrochloric acid was systematically studied through extensive testing. Experiments were conducted to separate and recover the rare earths from the hydrolysis solution. Kinetic studies on the acidolysis of phosphorite using hydrochloric acid show that the use of hydrochloric acid in the acidolysis of phosphorite is mainly controlled by a chemical reaction and is also a diffusion-controlled reaction. When 210 L of HCL per 100 kg of phosphorite was used at 30 °C for 360 min, 96.1% of the P2O5 and 95.0% of the rare earths are leached from the phosphorite. After defluorination and purification, the pH of the phosphate-acid solution is adjusted to 2.1 using sodium hydroxide, and a rare earth concentrate with rare earth content of 1.76 wt% is obtained; i.e., 90.1% of the rare earths are recovered. The rare earth content is increased to more than 5 wt% through multiple enrichment processes, with a total yield of 59.5%.

Zhijin phosphorus ore is a moderate and low-grade phosphorus rare-earth ore contained in mines. The separation and extraction of associated rare earth are important research topics. In this study, the migration behavior of rare earth during the thermal decomposition of Zhijin phosphorus ore and the separation and extraction of rare earth in phosphorus slag are discussed systematically. During the thermal decomposition process of phosphorus ore, almost all of the associated rare earth enters into the phosphorus slag phase but does not enter into the ferrophosphorus or gas phases. Amorphous calcium metasilicate and calcium fluosilicate are major components of phosphorus slag, and rare earth mainly exists as a calsil solid solution. Hydrochloric acid was used for acidolysis of the phosphorous slag. Under the following conditions, 96% of the rare earth in the phosphorous slag can be dissolved in the acidolysis solution: acid excess coefficient of 1.5, reaction time of 50 min and reaction temperature of 50 °C. The rare earth in the acidolysis solution was separated and recycled using oxalic acid as a precipitator and NaOH as a pH modifier. At pH of 1.7, rare-earth-enriched matter with rare-earth content of 2.1 wt% was obtained, and the recovery of the rare earth was 88%.

A sandwich-structured SnS2@reduced graphene oxide (SnS2@rGO) nanocomposite consisting of SnS2 sheets uniformly anchored on both sides of rGO sheets is presented. The SnS2@rGO nanocomposites, prepared through a dipping process combining with a hydrothermal method, show good electrochemical performance, including the high reversible capability of 959.2 mA h g−1 at 500 mA g−1 over 500 cycles, and superior rate performance. A full cell consisting of a commercial LiCoO2 cathode and the SnS2@rGO anode delivers the stable capacity of ∼821.3 mA h g−1 (anode basis) after 200 cycles at 100 mA g−1. The sandwich-structured SnS2@rGO nanocomposite accommodates volume changes during Li+ insertion and extraction and facilitates the rapid transport of ions and electrons. This high performance indicates that the presented SnS2@rGO nanocomposite is a promising anode candidate for practical application in Li-ion batteries.

This study investigates the impact of decision rights allocation in business groups on innovation performance. Using a sample of A-share manufacturing listed companies in China for 2009–2017, we find that group centralization has an inverted U-shaped relationship with innovation performance. This result suggests that moderate centralization is conducive to improving a group's innovation performance. Further, we determine that the relationship between group centralization and innovation performance varies according to the nature of ownership, growth opportunities, and market competition. State-owned property and growth opportunities of a group negatively moderate the relationship between group centralization and innovation performance; market competition positively moderates that relationship.

The porous structure within the cathode material influences the capacity and operating performance of Li S batteries. Here, we prepared special carbon material using sodium chloride as template/temporary space-holders to design mixture of micro−/meso−/macroporous structure with large surface area through a facile water bath and freeze-drying process. Such modification led to a high sulfur content of 73.2% with remarkable initial capacity of 1378 mAh g−1 at 0.1 A g−1, and maintains 48.6% after 100 cycles. Moreover, the Li S battery displayed superior rate capability of 807 mAh g−1 at 1.0 A g−1. This abundant micro−/meso−/macropores can improve the content of sulfur, relieve the loss of sulfur and exhibit superior cycling performance and rate capability.

The popularization of point-of-care (POC) testing is of great importance in healthcare diagnostics and other fields in the developing world, especially in resource-limited settings. To date, there are still great challenges in the development of simple, quick, affordable, yet highly effective and selective biosensors for POC testing. To meet the increasing need for POC testing, researchers need to consider biosensor miniaturization. In this review, we focus on recent advances in miniaturized biosensors for POC testing. We first review the miniaturization strategies, including handheld instruments and microfluidics-assisted miniaturized biosensing systems. Recent progress in recognition biosensing interactions for miniaturized biosensing systems is then summarized. We further describe how POC testing applications can be realized based on developments in integration, automation and multiplexing. Finally, the future prospects and remaining challenges of miniaturized biosensors for POC testing are discussed.