Nitrate Reduction by NiFe-LDH/CeO2: Understanding the Synergistic Effect between Dual-Metal Sites and Dual Adsorption.

Electrocatalytic nitrate reduction reaction (EC-NITRR) shows a significant advantage for green reuse of the nitrate (NO3-) pollutant. However, the slow diffusion reaction limits the reaction rate in practical EC-NITRR, causing an unsatisfactory ammonia (NH3) yield. In this work, a multifunctional NiFe-LDH/CeO2 with the dual adsorption effect (physisorption and chemisorption) and dual-metal sites (Ce3+ and Fe2+) was fabricated by the electrodeposition method. NiFe-LDH/CeO2 performed an expected ability of enrichment for NO3- through the pseudo-first-order and pseudo-second-order kinetic models, and the polymetallic structure provided abundant sites for effective reaction of NO3-. At-0.6 V vs RHE, the ammonia (NH3) yield of NiFe-LDH/CeO2 reached 335.3 µg h-1 cm-2 and the selectivity of NH3 was 24.2 times that of NO2-. The nitrogen source of NH3 was confirmed by 15NO3- isotopic labeling. Therefore, this work achieved the recycling of the NO3- pollutant by synergy of enrichment and catalysis, providing an alternative approach for the recovery of NO3- from wastewater.

Living arrangements and older People's labor force participation in Hong Kong, 1986-2016.

Using the 1% random sample of Hong Kong population census and by-census data (1986, 1991, 1996, 2001, 2006, 2011, 2016), we examine labor force participation (LFP) of older adults (aged 65+) and its association with living arrangements over a thirty-year span. Despite the large time period and the cohort variations in LFP, our cross-classified multilevel models (CCMM) showed a remarkably consistent linkage between the family context and older persons' LFP. Co-residence with adult children accompanies a lower level in older adults' LPF, compared with living alone or with the spouse only, but the extent of the reduction depends on the marital status of the children. Those living with married children have the lowest LFP, but living with unmarried children, sons in particular, increases the likelihood of employment compared with living with married children. We discuss the findings in light of changing macroeconomic conditions, marriage trends, and Chinese cultural traditions in Hong Kong.