The NdFeB permanent magnet is a critical material in digital electronics and clean energy industry. Traditional recovery processes based on the solvent extraction technique would consume high energy and large amounts of chemicals as well as resulting in abundant secondary organic wastes. In this work, a green process using deep eutectic solvents (DESs) in the selective leaching technology was designed to recover NdFeB permanent magnets. Nine kinds of DESs composed of guanidine were prepared and screened as the leachants. The guanidine hydrochloride–lactic acid (GUC–LAC) combined DES achieved the highest separation factor (>1300) between neodymium and iron through simple dissolution of their corresponding oxide mixture. The mass concentration of Nd dissolved in the GUC–LAC DES could reach 6.7 × 104 ppm. The viscosity of this type of DES at 50 °C was 36 cP, which was comparable to many common organic solvents. In a practical recovery of roasted magnet powders, the Nd2O3 product with 99% purity was facilely obtained with only one dissolution step, followed by a stripping process with oxalic acid. Even after 3 cycles, the GUC–LAC DES kept the same dissolution property and chemical stability. With such superior performances in selective leaching of rare earth elements from transition metals, the GUC–LAC DES is greatly promising in the rare earth element recovery field.

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Producing high-purity rare earth oxides (REOs) would generate large amounts of industrial wastes, and as a consequence, the rare earth industry needs to introduce green separation technology urgently. In this work, four deep eutectic solvents (DESs) as green solvents were employed for the separation and recovery of REOs, and the operation conditions of selective dissolution process were thoroughly investigated. It is found that the DES of guanidine hydrochloride (GUC) and lactic acid (LAC) at a molar ratio of 1:2 held a solubility up to 62000 ppm for La, whereas heavy REOs such as Dy 2 O 3 were almost insoluble in this DES, leading to extremely high separation selectivity between these two types of rare earths. The characterization results showed that the acidity and Cl − coordination of GUC-LAC were the main driving forces for the dissolution of REOs. This separation process based on GUC-LAC has the merits of moderate viscosity, mild operating conditions, and nontoxic and harmless raw materials, which shows a great prospect for application in the field of rare earth green separation.

The replacement of traditional solvents in lithium-ion battery recovery process by deep eutectic solvents (DESs) has been widely reported. This work proposed a DES modified by reducing agents for the efficient leaching of LiCoO2 (LCO) and lithium nickel cobalt manganese oxides (NCMs) to overcome the intractable difficulty of previous research (high viscosity, poor reuse performance, and operation conditions). The DES of guanidine hydrochloride (GUC) and lactic acid (LAC) with 1 wt % ascorbic acid could dissolve almost 100% of LCO and NCMs under a very mild condition at a solid–liquid ratio of 1:50. The maximum contents in GUC-LAC were 3188 ppm for Li and 19,045 ppm for Co. After stripping Co by oxalic acid and supplementing VC, GUC-LAC-VC could maintain the dissolution properties with at least three cycles. In addition, the acidity and reducibility were measured through Hammet acidity and cyclic voltammetry methods, as key factors for the dissolution of Li and Co.

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LINC00324 is a 2082 bp intergenic noncoding RNA. Aberrant expression of LINC00324 was associated with the risk of 11 tumors and was closely associated with clinicopathological features and prognostic levels of 7 tumors. LINC00324 can sponge multiple miRNAs to form complex ceRNA networks, and can also recruit transcription factors and bind RNA-binding protein HuR, thereby regulating the expression of a number of downstream protein-coding genes. LINC00324 is involved in 4 signaling pathways, including the PI3K/AKT signaling pathway, cell cycle regulatory pathway, Notch signaling pathway, and Jak/STAT3 signaling pathway. High expression of LINC00324 was associated with larger tumors, a higher degree of metastasis, a higher TNM stage and clinical stage, and shorter OS. Currently, four downstream genes in the LINC00324 network have targeted drugs. In this review, we summarize the molecular mechanisms and clinical value of LINC00324 in tumors and discuss future directions and challenges for LINC00324 research.

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The recovery of precious metals from discarded wastes is an attractive potential remedy for their supply disruption risk. Nevertheless, the use of conventional solvents in metallurgical processes has significant negative environmental effects. Here, we report peroxydisulfate (PDS)-based advanced oxidation process (AOPs) to develop a novel and efficient leaching process for recovering precious metals from spent catalysts. The PDS/NaCl photochemical system could fully dissolve palladium (Pd) and gold (Au) in 300 min. By introducing Fe(II), the PDS/FeCl2·4H2O solution functioned as Fenton-like system, which enhanced the leaching efficiency and required no xenon (Xe) lamp light irradiation. Electron paramagnetic resonance (EPR) and 18O isotope tracing experiments revealed the reactive oxidation species of SO4·-, ·OH and Fe(IV)=O were responsible for the oxidative dissolution of precious metals. Density functional theory calculations showed that the total energy barrier for the three species were 7.62, 18.46 and 17.52 kcal mol-1, respectively. Solvent leaching and one-step electrodeposition recovered high-purity precious metals and maintained solvent dissolution and electrochemical stability after 5 cycles. Strong acids, poisonous cyanide, volatile organic solvents, light irradiation, and photocatalysts were not used during recovery. This work will enable a green and sustainable precious metal recovery approach and encourage AOPs technology for secondary resource recycling.