Publications by authors named "Xia-Wen Qiu"

Chemical transfer across the air-water interface is one of the most important geochemical processes of global significance. Quantifying such a process has remained extremely challenging due to the lack of suitable technologies to measure chemical diffusion across the air-water microlayer. Herein, we present a fluorescence optical system capable of visualizing the formation of the air-water microlayer with a spatial resolution of 10 μm and quantifying air-water diffusion fluxes using pyrene as a target chemical.

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Despite ample evidence on spreading of e-waste derived hazardous materials, riverine transport of organic contaminants from e-waste recycling zones to surrounding areas has not been evaluated. To address this issue, passive and grab sampling methods were used to assess sediment-water diffusion and horizontal transport of polybrominated diphenyl ethers (PBDEs) and organophosphorus flame retardant (OPFRs) at upstream and downstream sites of two rivers in a typical e-waste recycling zone. Sediment acted as a source of BDE-17 with fluxes of 0.

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The partition coefficient (K) of an analyte between low-density polyethylene (LDPE) film and water is a critical parameter for measuring freely dissolved concentrations of the analyte with PE passive sampling devices. Measuring log K for super hydrophobic organic chemicals (HOCs) have been proven extremely difficult. The present study developed a large volume model for measuring log K of super HOCs, i.

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Objective: To study the effect of Gan-Pi regulatory needling (GPRN) in treating chloasma and its influences on female sex hormones, superoxide dismutase (SOD), lipid peroxide (LPO) and melanocyte-stimulating hormone (MSH).

Methods: Ninety chloasma patients were equally randomized to three groups, the treatment group treated with GPRN, the control group treated with conventional Western medicine and the blank group untreated. Changes in the scores of skin lesion (area and color) and symptom, as well as blood levels of female sex hormones, MSH, SOD and LPO were observed and compared after 3 months of treatment.

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