In Situ Constructing of Rigid-Soft Coupling Solid-Electrolyte Interphase on Silicon Electrode toward High-Performance Lithium Ion Batteries.

The application of Si anodes is hindered by some critical issues such as large volume changes of bare Si and fragile solid-electrolyte interface (SEI), resulting in low coulombic efficiency and rapid capacity decay. Herein, a multifunctional SEI film with high content of LiF is in situ constructed via the surface grafting of carbon-fluorine functionalized groups on silicon nanoparticles (SiNPs) during cycling. Mechanical study demonstrates that the incorporation of LiF with high modulus and unbroken carbon-fluorine groups with highly elastic guarantee the rigid-soft coupling SEI film on Si electrode. Furthermore, it is demonstrated that the rigid-soft coupling SEI film can effectively accommodate the volume expansion of Si nanoparticles during lithiation process, with the electrode expanding rate of only 114.16% after 100 cycles (263.87% for bare Si without surface modification). Afterward, with the aid of well-designed rigid-soft coupling SEI, the initial Coulomb efficiency of 89.8% is achieved, showing a reversible capacity of 1477 mAh g-1 after 200 cycles at 1.2 A g-1 . This work provides a simple and efficient solution that can potentially facilitate the practical application of Si anodes.

One-step selective separation and efficient recovery of valuable metals from mixed spent lithium batteries in the phosphoric acid system.

The recovery of valuable elements in spent lithium-ion batteries (LIBs) has attracted more and more attention. Efficient recovery of valuable elements from spent LIBs with lower consumption and shorter process is the target that people have been pursuing. In this study, the valuable metals (Ni, Co, Mn and Li) and FePO4 products are simultaneously recovered from mixed spent LiNixCoyMnzO2 and LiFePO4 in one step under the optimized condition of 0.88 M H3PO4, a mass ratio of LFP/NCM of 2:1, a L/S ratio of 33:1 and 80 ℃ for 120 min without additional auxiliary reagents. Over 60 % of acid consumption is reduced and the process of adjusting pH is avoidable. The leaching efficiencies of the valuable elements reach up to 99.1 % for Ni, 98.9 % for Co, 99.6 % for Li and 97.3 % for Mn. Almost all of Fe is precipitated as FePO4·2H2O. By means of the empirical model, the research on leaching kinetics demonstrates that the leaching reaction is internal diffusion-controlled with the apparent activation energy of valuable metals less than 30 kJ/mol. Furthermore, the redox reaction mechanism between spent LiBs has been explored. And the intrinsic driving force in the phosphoric acid system is found out. This finding may provide an innovative and selective recycling method for valuable elements from mixed spent LIBs with high economic benefit and fewer environmental footprints.

Recovery of valuable metals from spent lithium-ion batteries by complexation-assisted ammonia leaching from reductive roasting residue.

Recycling valuable metals in spent LIBs is not only in line with the purpose of resource recycling but also an important measure for environmental protection. In this article, a process using biomass reduction roasting followed by a unique complexation-assisted ammonia leaching is proposed. Using waste areca powder (WAP) as a biomass reducing agent, the roasted residue is leached in an aqueous solution for the carbonate. The leaching efficiencies of Ni, Co, and Mn reach over 99% under ammonia leaching conditions of 1.5 M ammonium citrate (AC), 3 M ethylenediamine (EDA). The kinetics of ammonia leaching indicates the activation energies of Ni, Co, and Mn are 51.8 kJ mol-1, 47.7 kJ mol-1, and 40.8 kJ mol-1, respectively, which shows the whole duration is controlled by chemical reactions. Most importantly, this study systematically explores the mechanism of ammonia leaching and provided a useful recommendation for selecting the right ammonium salt.

Altered expression levels of IDH2 are involved in the development of colon cancer.

IDH2 encodes a mitochondrial metabolic enzyme that converts isocitrate to α-ketoglutarate (α-KG) by reducing nicotinamide adenine dinucleotide phosphate (NADP(+)) to NADPH and participates in the citric acid cycle for energy production. Notably, this gene has been shown to be critical for cell proliferation. The abnormal expression of IDH2 has been reported in several types of cancer, and mutations in IDH2 have been identified in gliomas and acute myelogenous leukemia. The overexpression of IDH2 has been reported in endometrial, prostate and testicular cancer as well as in Kashin-Beck disease. In this study, we observed that IDH2 expression was significantly downregulated in early phase but was upregulated in advanced phase colon carcinoma compared to peritumoral tissues. In addition, we demonstrated that the growth of a colon carcinoma cell line was inhibited by IDH2-siRNA and increased following transfection with an IDH2-overexpressing plasmid. These results indicate that IDH2 may play a unique role in the development of colon carcinoma.

[Inhibitory effect of N-acetylcysteine upon atherosclerotic processes in rabbit carotid].

OBJECTIVE: To discuss the effect of N-acetylcysteine (NAC) upon matrix metalloproteinases (MMP) in the atherosclerotic processes in rabbit carotid. METHODS: The atherosclerotic models were generated in vitro by injuring rabbit internal carotid with arterial canal balloon. These rabbits were divided into 3 groups (15 mg/kg NAC, 30 mg/kg NAC and control group) and treated for 8 weeks. HE staining and immunohistochemistry were used to observe the plaque formation and the distribution of MMPs and ox-LDL. ELISA was used to detect the level of ox-LDL. And the protein levels of MMP-2 and MMP-9 in rabbit venous blood were detected by SDS PAGE zymography. The mRNA level of MMP-2 and MMP-9 were measured by RT-PCR and electrophoresis. RESULTS: As compared with the control group, NAC (15 mg/kg) group had a reduction of neointima of arterial lumen [(1.79 +/- 0.24) vs (2.78 +/- 0.17) mm2]. A decrease of endothelial thickness [(0.16 +/- 0.01) vs (0.24 +/- 0.02) mm2] and an increase of vascular cavity transverse [(0.58 +/- 0.10) vs (0.33 +/- 0.1) mm2] (P < 0.05) were observed. At week 8, the oxLDL levels decreased by 16% in NAC (30 mg/kg) group [(30.5 +/- 1.2) vs (36.2 +/- 1.8) mmol/L] (P < 0.01). Serum levels of pro-MMP-2, MMP-2 and pro-MMP-9 decreased markedly [INT/mm2: (311 +/- 19, 208 +/- 8, 283 +/- 7 vs 619 +/- 17, 574 +/- 8, 564 +/- 10) respectively, P < 0.01] in NAC (30 mg/kg) group. The levels of mRNA expression of MMP-2 and MMP-9 were (2.4 +/- 0.4, 2.8 +/- 0.2) vs (3.4 +/- 0.3, 3.7 +/- 0.5) respectively (P < 0.05). CONCLUSION: NAC inhibits the atherosclerotic formation, suppresses the levels of ox-LDL, MMP-9 and MMP-2 and downgrades the expression of matrix metalloproteinase mRNA.

[Effects of probucol, aspirin and atorvastatin combination therapy upon atherosclerosis].

OBJECTIVE: To investigate the effects of probucol, aspirin and atorvastatin (PAS) combination therapy upon atherosclerosis. METHODS: A total of 436 patients with coronary artery disease were selected and randomly divided into control group (aspirin 100 mg, atorvastatin 10 mg daily) and PAS group (aspirin 100 mg, atorvastatin 10 mg and probucol 0.25 g daily). After a 1-year treatment course, 378 cases remained in the study (201 in control group vs. 177 in PAS group). These patients were followed for throughout the study course and their serum levels of high density lipoprotein (HDL), ox-LDL, TXB2 and MMP-9 were measured at 6 and 12 months respectively. Twenty cases were diagnosed with carotid artery plaque by carotid ultrasound and 16 cases remained in the PAS group. They were followed with ultrasound for plaque thickness. RESULTS: In the control group, the pre-treatment level of MMPs and ox-LDL were not statistically different from the post-treatment level (P > 0.05). In the PAS group, the pre-treatment level of ox-LDL was (23.46 +/- 0.01) mmol/L and the post-treatment level (16.13 +/- 0.02) mmol/L. There was a decrease of 31.7% (P < 0.05). The pre-treatment level of MMPs and MMP-9 in the control group was not statistically different from the post-treatment level. The pre-treatment level of MMP-9 in the PAS group was (7.15 +/- 0.01) mmol/L and the post-treatment level (4.19 +/- 0.02) mmol/L. There was a decrease of 42.4% (P < 0.05). During the course of follow-up, the hospitalization rate, angina recurrence rate, myocardial infarction rate and mortality rate for the control group were 23 (11.4%), 28 (13.9%), 4 (2.0%) and 2 (1.0%) respectively. In the PAS group, the corresponding values were 6 (3.4%), 13 (7.3%), 1 (0.6%) and 0 respectively. All parameters of adverse events showed a significant decrease in the PAS group (P < 0.05). Among the cases with carotid plaque, the pretreatment measurements of intima thickness and plaque thickness were (0.103 +/- 0.002) cm and (0.248 +/- 0.001) cm while the post-treatment corresponding measurements (0.097 +/- 0.001) cm and (0.209 +/- 0.002) cm respectively. There was a significant difference between the PAS group and the control group (P < 0.05). CONCLUSION: Antioxidant probucol significantly inhibits the generation of ox-LDL and MMP-9. PAS therapy also reduces the plaque thickness and decreases the rate of adverse event in patients with atherosclerosis. Antioxidants can be considered as a new adjunct therapy in the treatment of atherosclerosis.