Zobrazení zdroje stránky Jorgensenulriksen1135

Time-series multivariate statistical analyses displayed distinct ecological patterns in microbial diversity between AMD- and non-AMD-environments. Focused ion beam-TEM micrographs and elemental mapping showed that silicate-stabilised passivation layers were successfully established across pyrite surfaces in organic-amended treatments, with these layers absent in unamended controls. Organic amendment and resulting increases in microbial abundance and diversity played an important role in sustaining these passivating layers in the long-term. Lightweight and wearable fabrics with rapid self-detoxification functions are highly desired to resist chemical warfare agents (CWAs). Metal organic frameworks (MOFs) with high specific surface area and customizability are singularly attractive because of their ability to effectively capture and catalytically degrade CWAs. Herein, photothermal graphene-based nanocomposite fabrics are designed by wet-spinning and chemical reduction of graphene oxide fibers followed by in situ growth of UiO-66-NH2. The flexible graphene fabrics decorated with UiO-66-NH2 nanoparticles exhibit an ultrafast photothermal catalytic decontamination of dimethyl 4-nitrophenyl phosphate (DMNP), a typical simulant of CWAs. The half-life of the degradation reaction decreases from 3.4 to 1.6 min under simulated solar light irradiation, a significant gain over the values reported in the literature. Furthermore, DMNP can be degraded in 20 min by the graphene/UiO-66-NH2 fabric, and even after 5 cycles the degradation efficiency still retains more than 92 %. More importantly, the photothermal conversion of graphene and its instantaneous heat transfer to the UiO-66-NH2 catalyst effectively accelerate the catalytic reaction kinetics, achieving the fast detoxification of DMNP. [https://www.selleckchem.com/products/Dihydroartemisinin(DHA).html find more] The combination of catalytic degradation of MOFs with photothermal conversion effect of graphene makes the lightweight and flexible fabrics promising for protection against CWAs and other pollutants. Uniformly dispersed silver nanoparticles (AgNPs) with remarkable colloidal stability were synthesised using chemical reduction method in lipopeptide biosurfactant reverse micelles. Transmission Electron microscopy (TEM), Scanning electron microscopy (SEM) and UV-vis spectroscopy analysis exhibited monodisperse nanoparticles with spherical morphology of diameter of 21 ± 2. The lipopeptide stabilized AgNPs displayed remarkable antibacterial activity with minimum inhibitory concentration (MIC) value of 15.625 μg/mL against Gram-negative Pseudomonas aeruginosa CB1 and Gram-positive Bacillus subtilis CN2 strains with a significant dose-dependent reduction of cell viability and loss of membrane integrity. Investigation of AgNPs internalization and dissolution assays demonstrated 42-fold higher leaching of the lipopeptide-stabilized AgNPs compared to the bare AgNPs, and concentration dependent increase in cellular uptake with subsequent damage to intracellular organelles. Further ultrastructural observation using TEM revealed internalization and strong binding of considerable amount of AgNPs on the lipopolysaccharide layer of the Gram-negative and peptidoglycans layer of Gram-positive bacteria indiscriminately, demonstrating robust antibacterial activity and potential application to treat multidrug resistant bacteria. V.Novel nanocopper-loaded black phosphorus (BP/Cu) nanocomposites were synthesized to synergistically exert enhanced antibacterial activities aimed at reducing antibiotics abuse. First, both BP and Cu display low biotoxicity, broadening their application in the microbiological field. Second, the unique electronic properties of BP enable BP/Cu nanocomposites to amplify antibacterial effects via interfacial charge transfer, resulting in a surge of reactive oxygen species (ROS). Third, BP/Cu nanocomposites are relatively stable, which helps to avoid the problem that nanocopper alone is highly oxidized. Finally, BP/Cu was synthesized in an environmentally-friendly manner by a one-step reduction method. The BP/Cu nanocomposites were characterized by transmission electron microscopy and atomic force microscopy. Their antibacterial properties were investigated comprehensively and discussed in detail by inhibition zone assays, dynamic growth curves, membrane potential assays, and live/dead baclight bacterial viability assays, all of which revealed the antimicrobial activities of BP/Cu nanocomposites. Absorption spectra were measured to determine which ROS species were responsible for the bactericidal mechanisms. In summary, our results demonstrated the potential of nanocomposites based on BP in antibacterial therapy due to its excellent electronic properties and outstanding biological performance. This will pave the way for avoiding antibiotic overuse and for providing security to humans and the environment. Nitrogen-doped carbon materials are proposed as promising metal-free catalysts for persulfate-mediated catalytic oxidation process, yet the nitrogen content in the final carbon products is typically low. Moreover, controversies remain in the unambiguous identification of active sites in nitrogen-doped carbons for persulfate activation. Here we report the facile synthesis of nitrogen-doped carbon material via one-step pyrolysis of urea and D-mannitol, which simultaneously combine ultrahigh nitrogen content (up to 33.75 at%) with apparent porous structure via transformation from graphitic carbon nitride. With this strategy, the highly nitrogen-doped porous carbon (NC1.0) exhibits excellent catalytic activity toward peroxymonosulfate (PMS) activation for oxidation of organic pollutants. Both experiments and density functional theory (DFT) calculations, for the first time, revealed that the electron-rich graphitic N and electron-deficient carbon atom adjacent to graphitic N in NC1.0 served as active sites for PMS reduction and oxidation toward the generation of hydroxyl radical (OH) and singlet oxygen (1O2), respectively, in which PMS oxidation was the main reaction in the course of PMS activation rendering 1O2 the dominant reactive oxygen species (ROS) in the NC1.0/PMS system. More importantly, NC1.0 presents robust stability in PMS activation, superior to most reported nitrogen-doped carbon-based catalysts, offering great promise for practical environmental remediation. V.