Excessive overpotential during charging is a major hurdle in lithium-oxygen (Li-O) battery technology. NO/NO redox mediation is an efficient way to substantially reduce the overpotential and to enhance oxygen efficiency and cycle life by suppressing parasitic reactions. Considering that nitrogen dioxide (NO) is a gas, it is quite surprising that NO/NO redox reactions can be sustained for a long cycle life in Li-O batteries with such an open structure.
View Article and Find Full Text PDFHousehold peanut exposure via skin in infants with impaired skin barrier function is a risk factor for peanut allergy development. The aim of this study is to investigate the peanut consumption of Koreans using national representative data. We used data from the Korean National Health and Nutrition Examination Survey 2012-2016, consisting of data from 17,625 adults who complete the survey.
View Article and Find Full Text PDFTo fabricate a sustainable lithium-oxygen (Li-O) battery, it is crucial to identify an optimum electrolyte. Herein, it is found that tetramethylene sulfone (TMS) and lithium nitrate (LiNO) form the optimum electrolyte, which greatly reduces the overpotential at charge, exhibits superior oxygen efficiency, and allows stable cycling for 100 cycles. Linear sweep voltammetry (LSV) and differential electrochemical mass spectrometry (DEMS) analyses reveal that neat TMS is stable to oxidative decomposition and exhibit good compatibility with a lithium metal.
View Article and Find Full Text PDFThe (1)H and (13)C NMR spectra of dicondensed indolinobenzospiropyrans as precursors of thermo- and photochromic spiropyrans, DC1-DC5, were completely assigned. Especially, the (1)H assignment and coupling characteristics of the diastereotopic protons at the carbon-3 position of the benzopyran rings were achieved by conducting (1)H-(1)H COSY and nOe experiments. The dihedral angles (theta(1), theta(2) and theta(3)) calculated from the experimental values of the vicinal coupling constants ((3)J) of DC5 are in good agreement with the observed values in the solid state.
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