Chemoprotective phytochemicals exhibit multiple activities and interact with several cellular receptors, including the aryl hydrocarbon (Ah) receptor (AhR). In this study we investigated the AhR agonist/antagonist activities of the following flavonoids: chrysin, phloretin, kaempferol, galangin, naringenin, genistein, quercetin, myricetin, luteolin, baicalein, daidzein, apigenin, and diosmin. We also investigated the AhR-dependent activities of cantharidin and emodin (in herbal extracts) in Ah-responsive MCF-7 human breast cells, HepG2 human liver cancer cells, and mouse Hepa-1 cells transiently or stably transfected with plasmids expressing a luciferase reporter gene linked to multiple copies of a consensus dioxin-responsive element. The AhR agonist activities of the compounds (1 and 10 micro M) were as high as 25% of the maximal response induced by 5 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and their potencies were dependent on cell context. Galangin, genistein, daidzein, and diosmin were active only in Hepa-1 cells, and cantharidin induced activity only in human HepG2 and MCF-7 cells. Western blot analysis confirmed that baicalein and emodin also induced CYP1A1 protein in the human cancer cell lines. The AhR antagonist activities of four compounds inactive as agonists in MCF-7 and HepG2 cells (kaempferol, quercetin, myricetin, and luteolin) were also investigated. Luteolin was an AhR antagonist in both cell lines, and the inhibitory effects of the other compound were dependent on cell context. These data suggest that dietary phytochemicals exhibit substantial cell context-dependent AhR agonist as well as antagonist activities. Moreover, because phytochemicals and other AhR-active compounds in food are present in the diet at relatively high concentrations, risk assessment of dietary toxic equivalents of TCDD and related compounds should also take into account AhR agonist/antagonist activities of phytochemicals.

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α-Fe(2)O(3) nanoparticle-loaded carbon nanofiber composites were fabricated via electrospinning FeCl(3)·6H(2)O salt-polyacrylonitrile precursors in N,N-dimethylformamide solvent and the subsequent carbonization in inert gas. Scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and elemental analysis were used to study the morphology and composition of α-Fe(2)O(3)-carbon nanofiber composites. It was indicated that α-Fe(2)O(3) nanoparticles with an average size of about 20 nm have a homogeneous dispersion along the carbon nanofiber surface. The resultant α-Fe(2)O(3)-carbon nanofiber composites were used directly as the anode material in rechargeable lithium half cells, and their electrochemical performance was evaluated. The results indicated that these α-Fe(2)O(3)-carbon nanofiber composites have high reversible capacity, good capacity retention, and acceptable rate capability when used as anode materials for rechargeable lithium-ion batteries.

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Layered ternary oxide cathode materials LiNi x Mn y Co1–x–y O2 (NMC) and LiNi x Co y Al1–x–y O2 (NCA) (referred to as ternary cathode materials, TCMs) with large reversible capacity, high operating voltage as well as low cost are considered as the most potential candidate materials for high energy density lithium ion batteries (LIBs) used in hybrid electric vehicles and electric vehicles (EVs). However, next-generation long-range EVs require an energy density of 800 W h kg–1 at the cathode level, which cannot be obtained using the commercially available TCMs. Developing high-voltage TCMs is a promising solution to enhance energy density of LIBs. Nonetheless, the capacity decay, poor long-term cycle life and microcrack at high operating voltage have limited their practical applications. In this paper, the development of the high-voltage TCMs is reviewed from degradation mechanism, cathode electrode modification, electrolyte design, solid state electrolytes and so on. The critical factors, recent progress and perspectives that improve the performance of TCMs with high-voltage operation are reviewed, which could provide important information and precautions to the practical use of these cathode materials under high operating voltage.

An ionic cobalt-PNP complex is developed for the efficient α-alkylation of ketones with primary alcohols for the first time. A broad range of ketone and alcohol substrates were employed, leading to the isolation of alkylated ketones with yields up to 98%. The method was successfully applied to the greener synthesis of quinoline derivatives while using 2-aminobenzyl alcohol as an alkylating reagent.

A series of iron complexes ligated by 2-imino-1,10-phenanthrolinyl ligands, LFeCl 2 (L ) 2-(ArNd CR)-1,10-phen), were synthesized and sufficiently characterized by elemental and spectroscopic analysis along with X-ray diffraction analysis. Activated with methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), these iron(II) complexes show high catalytic activities up to 8.95 × 10 7 g mol -1 (Fe) h -1 for ethylene oligomerization. The distribution of oligomers produced follows Schluz-Flory rules with high selectivity for R-olefins. Both the steric and electronic effects of coordinative ligands affect the catalytic activity and the properties of the catalytic products. The parameters of the reaction conditions were also investigated to explore the catalytic potentials of these complexes.

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