Tremendous developments in energy storage and conversion technologies urges researchers to develop inexpensive, greatly efficient, durable and metal-free electrocatalysts for tri-functional electrochemical reactions, namely oxygen reduction reactions (ORRs), oxygen evolution reactions (OERs) and hydrogen evolution reactions (HERs). In these regards, this present study focuses upon the synthesis of porous carbon (PC) or N-doped porous carbon (N-PC) acquired from golden shower pods biomass (GSB) via solvent-free synthesis. Raman spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) studies confirmed the doping of nitrogen in N-PC. In addition, morphological analysis via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) provide evidence of the sheet-like porous structure of N-PC. ORR results from N-PC show the four-electron pathway (average n = 3.6) for ORRs with a Tafel slope of 86 mV dec−1 and a half-wave potential of 0.76 V. For OERs and HERs, N-PC@Ni shows better overpotential values of 314 and 179 mV at 10 mA cm−2, and its corresponding Tafel slopes are 132 and 98 mV dec−1, respectively. The chronopotentiometry curve of N-PC@Ni reveals better stability toward OER and HER at 50 mA cm−2 for 8 h. These consequences provide new pathways to fabricate efficient electrocatalysts of metal-free heteroatom-doped porous carbon from bio-waste/biomass for energy application in water splitting and metal air batteries.

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Background: Acute respiratory infections (ARIs) are the leading cause of death among children less than 5 years in India. Poverty and malnutrition underlie both the high incidence and deaths of young children from pneumonia in SEAR countries.Methods: A hospital based prospective observational study was conducted in a tertiary care hospital. A total of 200 children admitted with signs of ALRI were included in the study. A portable oximeter was used to measure oxygen saturation with an appropriately sized sensor on the finger or the toe. Weight was recorded on a standardized digital weighing scale and plotted on standard WHO weight for age chart. Chi-square test was used to test the significance.Results: Out of 200 children studied hypoxemia was present in 90 children with a percentage of 45% and absent in 110 children with a percentage of 55%. Out of 90 children who had hypoxemia, 40 children had weight less than 3rd centile. Out 110 children who had did not have hypoxemia, only 24 children had weight less than 3rd centile. It was observed that children with Weight for age less than 3rd centile according to standard WHO charts had higher incidence of hypoxemia. This correlation was statistically significant at p value of 0.001.Conclusions: Based on the results of this study hypoxemia is widely prevalent in children aged between six months to five years presenting with acute lower respiratory tract infection. There was significant correlation with weight and hypoxemia in children aged between six months to five years with acute lower respiratory tract infection.