Rational A/B Site Ion Doping to Design Efficient and Stable Pr0.5Ba0.4Ca0.1Fe1-xCoxO3-δ Perovskites as Zinc–Air Batteries Cathode

The development of robust and efficient electrocatalysts for use in fuel cells and metal–air batteries has garnered a great deal of interest due to the quest for clean and renewable energy sources. In this paper, a promising Co-doped Pr0.5Ba0.4Ca0.1Fe1-xCoxO3-δ (x = 0, 0.2, 0.4, 0.6, 0.8; denoted as PBCFC-x, x = 0, 2, 4, 6, 8) with enhanced durability and electrocatalytic ORR/OER activity for zinc–air battery cathode catalysts is presented. Particularly, PBCFC-6 exhibits the best bifunctional catalytic activity in alkaline media among several materials, according to research using the RDE. The zinc–air battery with PBCFC-6 as the cathode catalyst delivered the smallest discharge–charge voltage difference at the current density of 10 mA·cm−2 and only increased by 0.031 V after 220 cycles (220 h), demonstrating its superior bifunctional catalytic activity and durability. The optimized electrochemical performance of both OER and ORR as well as stability in zinc–air batteries might result from the higher electrical conductivity, increasing concentration of adsorbed oxygen, and the greater proportion of Fe4+ (t2g3eg1) with optimal electron occupancy, owing to the partial replacement of Fe with Co

Obstacle Factors and Spatial Measurement of the Well-Being of the Elderly in China

This paper takes 31 provinces in China as the research object and constructs an evaluation index system for the well-being of the elderly in four aspects (health well-being, income well-being, social well-being and educational well-being) and uses a set-pair analysis model to spatially measure the well-being of the elderly. Then, barrier analysis is used to identify the main factors that lead to the differences in the well-being levels of the elderly in different regions. The results show that: (1) The provinces with higher levels of well-being of the elderly are mainly concentrated in the Beijing–Tianjin–Hebei region, Pearl River Delta region, Yangtze River Delta region and Bohai Sea Rim region. (2) The differences in income well-being levels are the largest among provinces, and the differences in health levels are the smallest among provinces. (3) Analysis of the barriers to elderly well-being shows that the number of beds per 1000 population in health care facilities, elderly dependency ratio, number of higher education schools for adults, number of nursing homes and urban road area per capita are the main factors affecting the differences in the well-being levels of elderly people across provinces. Finally, policy recommendations are made to introduce localized policies for the elderly in China to continuously promote solutions to the problems of the elderly

Migration of Toxic Metals from Ceramic Food Packaging Materials into Acid Food Simulants

Long-term extraction experiments were carried out on glazed tile specimens with 4 and 10% (v/v) acetic acid, 1% (w/v) citric acid, and 1% (v/v) lactic acid solution in three temperature conditions (20, 40, and 60°C) to investigate the effect of temperature and pH value on extraction of lead, cobalt, nickel, and zinc from ceramic food packaging materials and to study the extraction kinetics of toxic metals. Results showed that except at 60°C the amount of extraction of lead, cobalt, nickel, and zinc had linear dependence on time at longer times and removal of these toxic metals under other conditions increased linearly with the square root of the time, indicating a diffusion-controlled process. The amount of these toxic metals leached out from ceramic food packaging materials into the leachate, and the leaching rate increased with temperature and decreased with pH value of the food simulants. In addition, among these four toxic metals lead was the least leachable element, and nickel was the most leachable one. Disagreement between the ratios of the oxide of lead, cobalt, nickel, and zinc in the glaze and their release in the leachate suggested that extraction of these toxic metals was an incongruent dissolution process

A serious pulmonary infection secondary to disseminated Strongyloidiasis in a patient with Nephrotic syndrome

We report a case involving infection with Strongyloides stercoralis found in the sputum of a 66-year-old male patient who had a medical history of nephrotic syndrome and was treated with methylprednisolone and monthly intravenous cyclophosphamide therapy 3 months previously. This patient presented with stubborn pulmonary symptoms and signs, which was the mechanical destruction caused by larval migration. We found strongyloides in his sputum that provided diagnostic proof