ABSTRACT
With the rapid increase in the use of lithium-ion batteries (LIBs), the development of safe LIBs has become an important social issue. Replacing flammable organic liquid electrolytes in current LIBs with water can be an alternative route to resolve this safety concern. The water-in-salt (WIS) electrolytes received great attention as next-generation electrolytes due to their large electrochemical stability window. However, their high cathodic limit remains as a challenge, impeding the use of low-potential anodes. Here, we report the first biodirected synthesis of carbonaceous layers on anodes to use them as interlayers that prevent a direct contact of water molecules to anode particles. High-aspect ratio microbes are utilized as precursors of carbonaceous layers on TiO2 nanoparticles (m-TiO2) to enhance the conductivity and to reduce the electrolysis of WIS electrolytes. We selected the cylindrical shape of microbes that offers geometric diversity, providing us a toolkit to investigate the effect of microbe length in forming the network in binary composites and their impacts on the battery performance with WIS electrolytes. Using microbes with varying aspect ratios, the optimal microbe size to maximize the battery performance is determined. The effects of storage time on microbe size are also studied. Compared to uncoated TiO2 anodes, m-TiO2 exhibited 49% higher capacity at the 40th cycle and enhanced the cycle life close to anodes made with a conventional carbon precursor while using an 11% less amount of carbon. We performed density functional theory calculations to unravel the underlying mechanism of the performance improvement using microbe-derived carbon layers. Computational results show that high amounts of pyridinic nitrogen present in the peptide bonds in microbes are expected to slow down the water diffusion. Our findings provide key insights into the design of an interlayer for WIS anodes and open an avenue to fabricate energy storage materials using biomaterials.
ABSTRACT
Objetivo: Determinar la asociación entre el haber practicado submarinismo durante el servicio militar y el desarrollo de trastornos neurocognitivos en adultos mayores. Materiales y métodos: Estudio analítico retrospectivo, proviene del análisis de la base de datos del estudio: Fragilidad y dependencia funcional en adultos mayores, realizado entre 2010-2015 realizado por el personal del servicio de geriatría del Centro Médico Naval del Perú, en niveles asistenciales ambulatorios. En cuanto a la asociación se usó Chi2, p<0,05 e IC 95 %, para el modelo de regresión, se utilizó un modelo de Poisson. Resultados: Se analizaron en total 1020 participantes. 322 (42,42 %) de los participantes estuvieron en el rango de 71 - 80 años de edad. 240 (31,62 %) presentaban trastornos neurocognitivos. Los factores asociados a los trastornos neurocognitivos fueron los siguientes: el rango de edad entre 71 - 80 años de edad (RP=1,69; IC95 %: 1,12 - 2,54), enfermedad cerebro vascular (RP=1,48; IC95 %: 1,01 - 2,23) y especialidad de submarinismo (RP=2,36; IC95 %: 1,64 - 3,39). Tener grado militar superior se asoció con menor riesgo (RP=0,62; IC95 %: 0,43 - 0,89). Conclusiones: Los pacientes que han practicado el submarinismo tienen un mayor riesgo de padecer trastorno neurocognitivo, sin embargo, se requieren estudios prospectivos adicionales para corroborar dicha asociación.
Objective: To determine the association between the exposure to scuba diving during military service and the development of neurocognitive disorders in elderly people. Materials and methods: A retrospective analytical study, derived from the database analysis of the study "Fragility and functional dependence in older adults" conducted between 2010 and 2015 on an outpatient basis by the staff of the geriatrics service of the Centro Médico Naval del Perú (Peruvian Naval Medical Center). The chi-square test, p<0.05 and 95 % CI were used to establish said association, and the Poisson model was used as regression model. Results: A total of 1,020 participants were analyzed. Three hundred twenty-two (322 [42.42 %]) participants were between 71 and 80 years of age. Two hundred forty (240 [31.62 %]) had neurocognitive disorders. Factors associated with neurocognitive disorders were: age range between 71 and 80 years of age (PR = 1.69, 95 % CI: 1.12 - 2.54), cerebrovascular disease (PR = 1.48, 95 % CI: 1.01-2.23) and major in scuba diving (PR = 2.36, 95 % CI: 1.64-3.39). A higher military rank was associated with a lower risk of developing neurocognitive disorders (PR = 0.62, 95 % CI: 0.43-0.89). Conclusions: Patients who have practiced scuba diving have a higher risk of developing neurocognitive disorders; however, additional prospective studies are required to confirm this association.