Zimmermanrios7947

The action of fuel cells with proton-exchanged membranes (PEMs) requires the implementation of the hydrogen oxidation reaction (HOR) and the oxygen reduction reaction (ORR) on the opposite sides of the PEMs. Recently, based on several models of electrochemical reactions a significant decrease in the thermodynamic activation barrier of both reactions under plasmon assistance was reported. In this work, we propose the design of a PEM fuel cell with a plasmon-active catalytic surface providing plasmonic triggering and enhancement of fuel cell efficiency. In particular, we deposited bimetallic (Au@Pt) nanostructures on the PEM surface and integrated them into the fuel cell design. Plasmon excitation occurs on the Au nanostructures under light illumination at the corresponding NIR wavelength, while the Pt shell is responsible for the introduction of catalytic sites. Light illumination results in a significant enhancement of the electric current produced by the fuel cell. In particular, the electric current increased several times. Control experiments indicated that the observed enhancement takes place only when the light wavelength is in compliance with the plasmon absorption band and the contribution from thermal effects is negligible. The present approach for the introduction of plasmon assistance into the design of advanced fuel cells makes them suitable for increasing the fuel cell efficiency under sunlight.A covalent post-synthetic modification is applied in one of the most relevant polymers to obtain unprecedented switchable spin crossover (SCO) materials. Sodium acrylate supplier We also demonstrate that this material can be used as a selective chemo-sensor for VOCs (particularly, formaldehyde) thanks to solid/vapor reactions occurring between the polymer and the corresponding vapor.Anti-Stokes fluorescence induced by near-IR (NIR) radiation is particularly advantageous for the bioassay of complex samples, but most of the commonly used NIR-induced fluorescence nanomaterials such as up-conversion nanoparticles (UCNPs) do not exhibit satisfactory fluorescence intensity and work against achieving a highly sensitive bioassay. In this study, we a construct sensitive and specific bacteria biosensor based on the NIR-stimulated CaS Eu, Sm, Mn and SrS Ce, Sm, Mn nanoparticles. The fluorescent nanoparticles are conjugated with bacteria recognition fragments. In addition, the independent emission bands of these two types of fluorescent nanoparticles make it possible to detect and quantify Gram-positive strain and Gram-negative strain, simultaneously. Intense fluorescence and magnetic enrichment of magneto-fluorescence systems enable bacteria discrimination with the naked eye and improve sensitivity in trace bacteria detection ( less then 20 CFU mL-1). The linear relationship between the fluorescence intensity and bacterial concentration is established with a detection range of 25-106 CFU mL-1. Furthermore, this NIR-excited assay strategy demonstrates better anti-interference capability than UV/visible-excited assay methods, showing high potential and practical value for medical diagnostics and bacteria monitoring.A polymer filament, containing an O2-sensitive lumophore pigment, platinum(ii) (pentafluorophenyl) porphyrin coated onto nanoparticulate silica particles, i.e. PtTFPP/SiO2, is produced and used in a filament which is then 3D printed as O2-sensitive indicator dots (1 cm diameter, 30 μm thick) on a polyethylene terephthalate (PET) supporting film substrate. Two different filaments, prepared using the polymers, low density polyethylene (LDPE) and polylactic acid (PLA), respectively, are used to produce 3D printed PtTFPP/SiO2/LDPE and PtTFPP/SiO2/PLA O2-sensitive indicator dots, with dynamic ranges of 0-30% and 0-400% O2, respectively. The O2 response characteristics of these two, very different, indicator dots, such as sensitivity, response time and temperature sensitivity, are measured and compared with those of a commercial O2 indicator, FOSPOR (OceanInsight) and other commercial O2 indicators. The potential of this method for mass manufacture of O2 indicator dots and the likelihood that it can be extended to produce other optical indicators, such as those for ammonia or CO2, are discussed briefly.Increased consumption of fruits and vegetables is associated with reduced risk of age-related functional declines and chronic diseases, primarily attributed to their bioactive phytochemicals. Apples and blueberries are rich in phytochemicals with a wide range of biological activities and health benefits. Our previous research has shown the combination of apple peel extracts (APE) and blueberry extracts (BE) can synergistically promote the lifespan of Caenorhabditis elegans (C. elegans). The objectives of this study were to determine whether the extension of lifespan was involved in regulation of oxidative stress, and to explore the underlying mechanisms of action. The results showed that the combination of APE and BE could synergistically ameliorate oxidative stress by improving antioxidant enzyme activities and enhancing resistance to paraquat. Meanwhile, treatment with APE plus BE could down-regulate the overexpression of reactive oxygen species (ROS) and affect the expression of antioxidant related genes, including sod-3, cat-1, ctl-1, skn-1, mev-1 and isp-1. However, administration with APE plus BE abolished the extension of the lifespan of skn-1(zu135) mutants, and inhibited the expression of skn-1 downstream genes, including gcs-1, gst-4 and gst-7. In addition, supplementation with APE plus BE could promote the migration of SKN-1 into the nucleus, which eliminated improvement to ROS and paraquat. In conclusion, the combination of APE and BE could synergistically protect against oxidative stress in C. elegans via the SKN-1/Nrf2 pathway. This study provided the theoretical basis to explore the combination of phytochemicals in the prevention of aging regulated by oxidative stress.The elusive flavin semiquinone intermediate found in flavoproteins such as cryptochromes has been obtained in aqueous solution by single electron reduction of the natural FMN cofactor using sodium ascorbate. This species was formed in the local hydrophobic microenvironment of a modified polyethyleneimine and characterized by UV-Visible, fluorescence and EPR spectroscopies.