Steffensenappel6645
This article used O3 to mimic the oxidizing environment in the Li-ion battery by providing active atomic oxygen. It provided insights into the chemically sensitized gas-phase low-temperature chemistry of DEC and explained the mechanism of battery degradation involving the low-temperature oxidation at the electrolyte solvent and the cathode interface from 400 to 500 K.Electrochemical capacitors (ECs) have emerged as reliable and fast-charging electrochemical energy storage devices that offer high power densities. Their use is still limited, nevertheless, by their relatively low energy density. Because high specific surface area and electrical conductivity are widely seen as key metrics for improving the energy density and overall performance of ECs, materials that have excellent electrical conductivities but are otherwise nonporous, such as coordination polymers (CPs), are often overlooked. Here, we report a new nonporous CP, Ni3(benzenehexathiolate) (Ni3BHT), which exhibits high electrical conductivity of over 500 S/m. When used as an electrode, Ni3BHT delivers excellent specific capacitances of 245 F/g and 426 F/cm3 in nonaqueous electrolytes. Structural and electrochemical studies relate the favorable performance to pseudocapacitive intercalation of Li+ ions between the 2D layers of Ni3BHT, a charge-storage mechanism that has thus far been documented only in inorganic materials such as TiO2, Nb2O5, and MXenes. This first demonstration of pseudocapacitive ion intercalation in nonporous CPs, a class of materials comprising thousands of members with distinct structures and compositions, provides important motivation for exploring this vast family of materials for nontraditional, high-energy pseudocapacitors.Over the past decade, porphyrin derivatives have emerged as invaluable synthetic building blocks and theranostic kits for the delivery of cellular fluorescence imaging and photodynamic therapy. Tetraphenylporphyrin (TPP), its metal complexes, and related derivatives have been investigated for their use as dyes in histology and as components of multimodal imaging probes. The photophysical properties of porphyrin-metal complexes featuring radiometals have been a focus of our attention for the realization of fluorescence imaging probes coupled with radioimaging capabilities and therapeutic potential having "true" theranostic promise. selleck kinase inhibitor We report hereby on the synthesis, radiochemistry, structural investigations, and preliminary in vitro and in vivo uptake studies on a range of functionalized porphyrin-based derivatives. In pursuit of developing new porphyrin-based probes for multimodality imaging applications, we report new functionalized neutral, polycationic, and polyanionic porphyrins incorporating nitroimidazoaphy (PET) probes have been designed and tested hereby, using TPP and related functional free base porphyrins as the bifunctional chelator synthetic scaffold and 111In[In] or 68Ga[Ga], respectively, as the central metal ions. Interestingly, for simple porphyrin conjugates good radiochemical incorporation was obtained for both radiometals, but the presence of peptides significantly diminished the radio-incorporation yields. Although the gallium-68 radiochemistry of the bombesin conjugates did not show radiochemical incorporation suitable for in vivo studies, likely because the presence of the peptide changed the behavior of the TPP-NH2 synthon taken alone, the optical imaging assays indicated that the conjugated peptide tags do mediate uptake of the porphyrin units into cells.The copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction has drawn increasing attention in the field of analytical science. However, the poor stability of Cu(I) usually hinders not only the simplicity of the click reaction but also its applications in precise analyses. Therefore, the development of a nanocatalyst containing stable Cu(I) is of great significance for broadening the application of CuAAC-based assays. Herein, inspired by the active center structure of natural multicopper oxidases (MCOs), we successfully prepared a novel nanocatalyst containing abundant stable Cu(I) as an artificial "clickase" (namely, CCN) by using glutathione to stabilize Cu(I). The stability and enzyme-like catalytic activity in the CuAAC reaction of the prepared CCN clickase were studied, and the catalytic mechanism of the CCN clickase-mediated CuAAC reaction between 3-azide-7-hydroxycoumarin (Azide 1) and propargyl alcohol (Alkyne 2) was also revealed. Compared with the existing solid CuO nanocatalysts used in CuAAC-based assays, CCN clickases exhibited plenty of superior properties (including high stability, excellent catalytic activity, no requirements of dissolution and reducing agents/radical initiator during the detection, well-defined porosities benefiting the substrate diffusion, and good biocompatibility), which can greatly increase the reaction efficiency and shorten the detection time. Encouraged by these remarkable performances, CCN clickases were used as labels to establish a new catalytic click fluorescence immunoassay for foodborne pathogens. Notably, the proposed CCN clickase-based immunoassay exhibited high analytical performances for the quantification of Salmonella enteritidis in the linear range of 102-106 CFU/mL with a limit of detection as low as 11 CFU/mL. The developed method has also been used in the determination of S. enteritidis in food samples, showing its great potential in the detection of foodborne pathogens.Dispersing graphene sheets in liquids, in particular water, could enhance the transport properties (like thermal conductivity) of the dispersion. Yet, such dispersions are difficult to achieve since graphene sheets are prone to aggregate and subsequently precipitate due to their strong van der Waals interactions. Conventional dispersion approaches, such as surface treatment of the sheets either by surfactant adsorption or by chemical modification, may prevent aggregation. Unfortunately, surfactant-assisted graphene dispersions are typically of low concentration ( less then 0.2 wt %) with relatively small sheets ( less then 1 μm lateral size) while chemical modification is punished by increased defect density within the sheets. We investigate here a new approach in which the concentration of dispersed graphene in water is enhanced by the addition of a fibrous clay mineral, sepiolite. As we demonstrate, the clay particles in water form a kinetically arrested particle network within which the graphene sheets are effectively trapped.