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Zero-valent iron nanoparticles (nZVI) are emerging multifunctional agents for contaminant treatment. However, Fe2O3-Fe3O4 nanoparticles (NIO), which are generated when nZVI is oxidized, can also make a meaningful contribution to the photocatalytic degradation of organics. Taking this into account, NIO and a Fe2O3-Fe3O4-montmorillonite nanocomposite (NIO-M) were prepared, and their morphology and microstructure were investigated via a series of characterization methods. The presence of montmorillonite is critical to decreasing the aggregation and size of the crystals, which helps improve the thermal stability of the crystals. The photocatalysis performance of NIO and NIO-M for the degradation of methyl orange was evaluated, and the data indicated that NIO-M exhibited an excellent optical response and photocatalytic activity in the visible region. The degradation rate of methyl orange was 1.47 times faster within 45 min of irradiation compared with NIO. The results indicate that NIO-M is a promising type of visible-light-driven photocatalyst for the degradation of organics in aqueous solutions. [ABSTRACT FROM AUTHOR]

This research concerns the adsorption of CuII and NiII using zero-valent iron nanoparticles supported by kaolinite (nZVI-Kaolinite). The characterization studies indicated that the surface of kaolinite or the kaolinite fragments were filled with nZVI particles. The kinetics of CuII and NiII adsorption were evaluated for various contact times. The adsorption of CuII and NiII at different initial concentrations was examined by injecting 0.5 g of adsorbent to achieve equilibrium. The adsorption of CuII and NiII was a chemisorption process, which fitted well with the Freundlich and the Temkin isotherm models. The low value of activation energy suggests the occurrence of a redox process and both physical and chemical processes for CuII and NiII adsorption respectively. The negative values for the Gibbs free energy (δG0) and enthalpy of adsorption (δH0) revealed that the adsorption process was spontaneous and exothermic. Both surface diffusion and pore diffusion were involved in the rate-limiting step. The possible removal mechanisms involved redox, adsorption, precipitation, and co-precipitation, depending on the adsorption process studied (CuII or NiII adsorption). [ABSTRACT FROM AUTHOR]

Highlights: [•] Brick-making using coal gangue is one of the important coal gangue recycling utilization. [•] The enrichment behaviors and health impacts of natural radionuclides during coal gangue brick making are studied. [•] The emission characterizations of toxic elements from the coal gangue brick firing processes are evaluated. [ABSTRACT FROM AUTHOR]

Comprehensive Summary With the rapid development of solid‐state batteries, solid‐state polymer electrolytes (SPEs) have attracted widespread attention due to their excellent environmental friendliness, designability, and forming film ability. However, due to the limited conductive path of polymers, lithium‐ion diffusion kinetics are limited, and low ion conductivity is a huge challenge for SPEs in practical applications. This work provides a polyethylene oxide (PEO) based polymer electrolyte, which has multiple paths of ion diffusion caused by organic polymer framework of poly(hexaazatrinaphthalene) (PHATN). The unique porous channel, the specific surface characteristics, the coordination of ‐C=N‐ groups in PHATN with Li+, combined with the mobility of PEO segments, make the SPEs have a good ability to conduct Li+. Interestingly, the PHATN‐PEO/lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) composite electrolytes exhibit excellent electrochemical properties. At room temperature, the conductivity of PHATN‐PEO electrolyte can reach 1.03 × 10–4 S·cm–1, which is greatly improved compared with 3.9 × 10–6 S·cm–1 of PEO. Delightedly, the lithium‐ion transference number of PHATN‐PEO electrolyte achieves 0.61, and the electrochemical window increases to 4.82 V. The LFP/1%PH‐PEO/Li solid‐state batteries show good electrochemical cycles. This work reveals an efficient stratagem for the design of polymer solid‐state electrolytes. [ABSTRACT FROM AUTHOR]

The combustion characteristics, kinetic analysis and selenium retention-emission behavior during co-combustion of high ash coal (HAC) with pine wood (PW) biomass and torrefied pine wood (TPW) were investigated through a combination of thermogravimetric analysis (TGA) and laboratory-based circulating fluidized bed combustion experiment. Improved ignition behavior and thermal reactivity of HAC were observed through the addition of a suitable proportion of biomass and torrefied. During combustion of blends, higher values of relative enrichment factors in fly ash revealed the maximum content of condensing volatile selenium on fly ash particles, and depleted level in bottom ash. Selenium emission in blends decreased by the increasing ratio of both PW and TPW. Higher reductions in the total Se volatilization were found for HAC/TPW than individual HAC sample, recommending that TPW have the best potential of selenium retention. The interaction amongst selenium and fly ash particles may cause the retention of selenium. [ABSTRACT FROM AUTHOR]

Bacteria in tumor microenvironments promote carcinogenesis and trigger complications, suggesting the significance of intervening in bacterial growth in cancer treatment. Here, dendrimer-derived mimics (DMs) of host defense peptides (HDPs) were designed for antibacterial and anticancer therapy, which feature a dendronized polylysine core and polycaprolactone arms. DMs displayed not only remarkable activities against Staphylococcus aureus and human lung cancer cells, but also exceptional selectivity. The membranolytic mechanism revealed by morphology analysis explained their low susceptibility to induce resistance. Further, the optimized DM inhibited tumor growth in the subcutaneous tumor model when administered via intraperitoneal injection and exhibited negligible toxicity to tissues. Overall, we combined the superiority of dendrimers and the mechanism from HDPs to design agents with dual antibacterial and anticancer activities that possess great potential for clinical oncology therapy.

This study measured the concentrations of eight heavy metals, including copper (Cu), zinc (Zn), lead (Pb), chromium (Cr), cadmium (Cd), iron (Fe), manganese (Mn) and nickel (Ni), and the stable isotope ratios of δ 13 C and δ 15 N in 129 fish samples collected from the Yellow River Estuary (YRE) of China. Accumulation characteristics and possible sources of these heavy metals (HMs) were analyzed. The levels of HMs presented high variations among sampling sites, higher concentrations of ∑HMs were observed at the sites closest to the estuary. Cu and Cd in fishes of the YRE were much higher than those found in the fishes of other rivers of China. Furthermore, the mean concentrations of Cu, Zn, Pb, Cr and Cd were also significantly higher than those measured in the fishes of the same region twenty years ago. According to the results of correlation analysis and principal components analysis (PCA), Pb, Cr, Fe, Mn and Ni might be originated from similar sources. The values of δ 13 C and δ 15 N presented high variation in fishes, indicating a wide range of energy sources and trophic status of the investigated fish species. The mean concentrations of Pb, Cr and Cd in fishes were all lower than the recommended values enacted by the Chinese government. The human health risk assessment showed that the estimated daily intake (EDI) of these HMs did not exceed the permissible tolerable daily intake (PTDI) and oral reference dose (RfD), indicating a situation of no potential health risk for consumption of these fish species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Despite advanced sterilization and aseptic techniques, infections associated with medical implants have not been eradicated. Most present coatings cannot simultaneously fulfil the requirements of antibacterial and antifungal activity as well as biocompatibility and reusability. Here, we report an antimicrobial hydrogel based on dimethyldecylammonium chitosan (with high quaternization)-graft-poly(ethylene glycol) methacrylate (DMDC-Q-g-EM) and poly(ethylene glycol) diacrylate, which has excellent antimicrobial efficacy against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Fusarium solani. The proposed mechanism of the antimicrobial activity of the polycationic hydrogel is by attraction of sections of anionic microbial membrane into the internal nanopores of the hydrogel, like an 'anion sponge', leading to microbial membrane disruption and then microbe death. We have also demonstrated a thin uniform adherent coating of the hydrogel by simple ultraviolet immobilization. An animal study shows that DMDC-Q-g-EM hydrogel coating is biocompatible with rabbit conjunctiva and has no toxicity to the epithelial cells or the underlying stroma.

Antimicrobial peptides (AMPs), particularly those effective against methicillin-resistant Staphylococcus aureus ( S. aureus ) and antibiotic-resistant Pseudomonas aeruginosa ( P. aeruginosa ), are important alternatives to antibiotics. Typical peptide synthesis methods involving solid-phase sequential synthesis are slow and costly, which are obstacles to their more widespread application. In this paper, we synthesize peptides via ring-opening polymerization of alpha-amino acid N-carboxyanhydrides (NCA) using a transition metal initiator. This method offers high potential for inexpensive synthesis of substantial quantities of AMPs. Lysine (K) was chosen as the hydrophilic amino acid and alanine (A), phenylalanine (F), and leucine (L) as the hydrophobic amino acids. We synthesized five series of AMPs (i.e., P(KA), P(KL), P(KF), P(KAL), and P(KFL)), varied the hydrophobic amino acid content from 0 to 100%, and determined minimal inhibitory concentrations (MICs) against clinically important Gram-negative and Gram-positive bacteria and fungi (i.e., Escherichia coli ( E. coli ), P. aeruginosa , Serratia marcescens ( S. marcescens ), and Candida albicans ( C. albicans ). We found that P(K(10)F(7.5)L(7.5)) and P(K(10)F(15)) show the broadest activity against all five pathogens and have the lowest MICs against these pathogens. For P(K(10)F(7.5)L(7.5)), the MICs against E. coli , P. aeruginosa , S. marcescens , S. aureus , and C. albicans are 31 microg/mL, 31 microg/mL, 250 microg/mL, 31 microg/mL, and 62.5 microg/mL, while for P(K(10)F(15)) the respective MICs are 31 microg/mL, 31 microg/mL, 250 microg/mL, 31 microg/mL, and 125 microg/mL. These are lower than the MICs of many naturally occurring AMPs. The membrane depolarization and SEM assays confirm that the mechanism of microbe killing by P(K(10)F(7.5)L(7.5)) copeptide includes membrane disruption, which is likely to inhibit rapid induction of AMP-resistance in pathogens.