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Bicarbonate (HCO3 –), one of the most abundant anions in fresh water, is relatively nontoxic and cheap. In this work, the degradation of organic dyes with simple copper(II) ions as the catalyst in the HCO3 – solution using H2O2 as the oxidant was investigated. It was found that the dyes such as Orange II (AOII), Methyl Orange, Methyl Red, and Toluidine Blue could be efficiently decolorized by the system. The rate of H2O2 decomposition was much slower in the presence of the dyes than that without the pollutants. The formed copper(II) species at different HCO3 – concentrations were calculated, and CuCO3 was suggested to be more reactive. The radical scavenging measurements further implied that the produced higher oxidation state of copper, Cu(III), was to be responsible for the dye decolorization. A possible pathway of AOII degradation was also proposed based on the detected intermediate products by electrospray ionization mass spectrometry. This study can provide us a simple, effective, and economical system ideal for the treatment of toxic and nonbiodegradable organic dyes.

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Semiconducting carbon nitride materials (g-C 3 N 4 ) were investigated as metal-free catalysts for the activation of peroxymonosulfate (PMS) under visible light irradiation to degrade organic dyes in aqueous solution. X-ray diffraction, scanning electron microscopy, N 2 adsorption/desorption isotherms, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy were used to characterize the properties of the material. The effect of several parameters including the concentration of catalyst, PMS and organic dye, and initial solution pH on its catalytic activity was also investigated. It was found that the obtained g-C 3 N 4 can effectively activate PMS under visible light irradiation to generate strong sulfate radicals which was highly active for Acid Orange 7 (AO7) and other organic dyes degradation. The catalyst also presented a long-term stability during multiple runs. Based on intermediate detections, the degradation pathway of AO7 in the g-C 3 N 4 /PMS/Vis system was proposed. This study demonstrated a promising approach for the activation of green oxidant, PMS, by the newly-developed polymer photocatalysts for environmental remediation and oxidation catalysis.

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A magnetically recyclable nanocomposite, manganese oxide octahedral molecular sieves (OMS-2) coated Fe3O4 nanoparticle, was prepared by a facile solvent-free process, and used for peroxymonosulfate activation and pollutants degradation.

Ensuring equality and adequacy of care for older adults is vitally important. This study investigates the relationships between childhood adversities and unmet long-term care needs of older adults in China and the mediation effects of family relationships. The data came from a nationally representative sample of older Chinese adults aged 60 and over with long-term care needs ( N = 2186). We conducted mediation analyses and decomposed the total effects of childhood adversities on unmet needs into direct and indirect effects. The probability of unmet needs is significantly higher among older adults experiencing childhood adversities. Satisfaction with marriage mediates the association between childhood adversities and unmet personal care needs. Relationships with children mediate the association between childhood adversities and unmet domestic care needs. The causes of unmet needs can be traced back to early life, which underscores the importance of concerted efforts in family, education and long-term care policies to tackle unmet needs.