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Silicon nanoparticles (SiNPs) with a median size of 51 nm are prepared by the sand mill from waste silicon, and then carbon-interweaved SiNPs/graphite anode materials are designed. Because of the size of SiNPs is restricted below a critical fracture size of 150 nm as well as the rational decoration of carbon and graphite, fracture of SiNPs, and volume deformation of active materials are highly alleviated, leading to low impedance, enhanced electrochemical reaction kinetics, and good electronic connection between active materials and current collector. Furthermore, delithiation reversibility of the formed crystalline Li 15 Si 4 alloy is enhanced. As a result, the anode with 10.5 wt % content of Si (including SiO x ) delivers a properly high initial reversible capacity of 505 mA h g -1 , high cycling stability with capacity retentions of 86.3%, and 91.5% at 0.1 and 1 A g -1 after 500 cycles, respectively. After cycling at a series of higher current densities, the reversible capacity recovers to the original level completely (100% recovery) when the current density is set back to the original value, exhibiting outstanding rate performance. The results indicate that the silicon-carbon anode can achieve high cycling performances with enhanced delithiation reversibility of the formed crystalline Li 15 Si 4 alloy by restricting size of SiNPs and decoration of carbon materials, which are discussed systematically. The SiNPs are recycled from waste Si, and synthetic strategy of anode materials is very facile, cost-effective, and nontoxic, which has potential for industrial production.

Residual Si was produced on a furnace wall when upgraded metallurgical grade Si was refined by electron beam melting. It was then recycled to prepare Si-SiO x nanoparticles with an average size of 100 nm by planetary ball milling. The obtained Si-SiO x nanoparticles mainly consist of amorphous Si, crystalline Si and amorphous SiO x , which was confirmed by XRD, FTIR, XPS and TEM. SiO x is mainly composed of SiO 2 and SiO 1.35 . Distilled water used as a grinding aid not only enhances milling efficiency, but also plays a key role in obtaining SiO x . During refining of upgraded metallurgical grade Si, the deposition pattern of residual Si on furnace wall agrees with model of three-dimension growth. Growth of Si-SiO x nanoparticles is the mutual effect of distilled water and ball milling. Si-SiO x nanoparticles were doped into phenolic resin pyrolysis carbon as anode materials for lithium ion batteries, and 10% doping was observed to improve the specific capacity. After 500 cycles, specific capacity of delithiation remained around 550 mA h/g. It suggests the residual Si is a value-added by-product, and it can be recycled as anode materials for lithium ion batteries., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Combination chemotherapy is widely exploited for suppressing drug resistance and achieving synergistic anticancer efficacy in the clinic. In this paper, the nanostructured targeting methotrexate (MTX) plus pemetrexed (PMX) chitosan nanoparticles (CNPs) were developed by modifying methoxy polye (thylene glycol) (mPEG), in which PEGylation CNPs was used as stealth nanocarriers (PCNPs) and MTX was employed as a targeting ligand and chemotherapeutic agent as well. Studies were undertaken on human lung adenocarcinoma epithelial (A549) and Lewis lung carcinoma (LLC) cell lines, revealing the anti-tumor efficacy of nanoparticle drug delivery system. The co-delivery nanoparticles (MTX-PMX-PCNPs) had well-dispersed with sustained release behavior. Cell counting kit-8 (CCK8) has been used to measure A549 cell viability and the research showed that MTX-PMX-PCNPs were much more effective than free drugs when it came to the inhibition of growth and proliferation. Cell cycle assay by flow cytometry manifested that the MTX-PMX-PCNPs exhibited stronger intracellular taken up ability than free drugs at the same concentration. In vivo anticancer effect results indicated that MTX-PMX-PCNPs exhibited a significantly prolong blood circulation, more tumoral location accumulation, and resulted in a robust synergistic anticancer efficacy in lung cancer in mice. The results clearly demonstrated that such unique synergistic anticancer efficacy of co-delivery of MTX and PMX via stealth nanocarriers, providing a prospective strategy for lung cancer treatment.