Holmemouridsen3860

Besides the conventional concentration additivity, several studies have suggested that different classes of POPs possibly act synergistically or antagonistically based on their concentration. However, ecotoxicology information is still recorded in a scattered and inadequate manner, including lack of enough avian species, limited number of POPs investigated, and insufficient geographical representation, and thus our understanding of the effects of POPs on birds remains rudimentary, although mechanistic understanding of their mode of action is progressing. Particularly, research on what happens to wild bird populations and their ecosystems under POP stress is still unavailable. Thus, our aim is to predict and trace the effects POPs at different biological organization levels, especially from the molecular, cellular and individual levels to the population, community and ecosystem levels because of the limited and scattered information, as mentioned above.Correction for 'Conductive interface promoted bifunctional oxygen reduction/evolution activity in an ultra-low precious metal based hybrid catalyst' by Shreya Sarkar et al., Chem. Commun., 2021, 57, 1951-1954, DOI 10.1039/D0CC08225B.Polyethylene glycol grafting has played a central role in preparing the surfaces of nano-probes for biological interaction, to extend blood circulation times and to modulate protein recognition and cellular uptake. However, the role of PEG graft dynamics and conformation in determining surface recognition processes is poorly understood primarily due to the absence of a microscopic picture of the surface presentation of the polymer. Here a detailed NMR analysis reveals three types of dynamic ethylene glycol units on PEG-grafted SiO2 nanoparticles (NPs) of the type commonly evaluated as long-circulating theranostic nano-probes; a narrow fraction with fast dynamics associated with the chain ends; a broadened fraction spectrally overlapped with the former arising from those parts of the chain experiencing some dynamic restriction; and a fraction too broad to be observed in the spectrum arising from units closer to the surface/graft which undergo slow motion on the NMR timescale. We demonstrate that ethylene glycol units transition between fractions as a function of temperature, core size, PEG chain length and surface coverage and demonstrate how this distribution affects colloidal stability and protein uptake. The implications of the findings for biological application of grafted nanoparticles are discussed in the context of accepted models for surface ligand conformation.The temperature of the solution-phase spin-crossover equilibrium in iron(ii) complexes of 4-alkylsulfanyl-2,6-dipyrazol-1-ylpyridine (bppSR) complexes depends strongly on the alkylsulfanyl substituent. DFT calculations imply this reflects the conformation of the alkylsulfanyl groups, which lie perpendicular to the heterocyclic ligand donors in [Fe(bppStBu)2]2+ but are oriented co-planar with the ligand core for smaller SR substituents.Transition metal nitrides are promising mediators for improving the electrochemical performance of lithium-sulfur (Li-S) batteries, but the synthesis of ultrafine and durable nanoparticles in the absence of ammonia gas is still a great challenge. Herein, we reported a new method for the fabrication of ultrafine vanadium nitride (VN) nanoparticles uniformly embedded into N-doped porous carbon using a main-chain imidazolium-based ionic polymer (ImIP) containing metavanadate anions as a precursor. ImIP not only serves as sole carbon and nitrogen sources, but also effectively inhibits the aggregation and coalescence of VN nanoparticles during pyrolysis. Benefiting from the ultrafine particle size, high polarity and good electrocatalytic effects of VN, both redox kinetics of sulfur species and chemical adsorbability toward polysulfides are greatly expedited. The resultant electrode exhibits superior cycling stability with a low average capacity decay rate of 0.035% for 1200 cycles at a high rate of 5 C. This work develops a facile ammonia-free approach to fabricate ultrafine VN nanoparticles for improving electrochemical behaviors of Li-S batteries.Graphene oxide (GO) is a classic two dimensional (2D) building block that can be used to develop high-performance materials for numerous applications, particularly in the energy and environmental fields. Currently, the precise assembly of GO nanosheets into macroscopic nanohybrids of superior strength and toughness is desirable, and faces challenges and trade-offs. Herein, we exploited the freshly established polycationitrile method as a powerful molecular crosslinking strategy to engineer ultratough and ultrastrong GO/polymer hybrid films, in which a covalent triazine-based network was constructed in a mild condition to reinforce the interface between GO nanosheets. The tensile strength and toughness reached 585 ± 25 MPa and 14.93 ± 1.09 MJ m-3, respectively, which, to the best of our knowledge, are the current world records in all GO-based hybrid films. As an added merit of the tailor-made polymer crosslinker, the high mechanical performance can be maintained in large part at an extremely high relative humidity of 98%. This emerging interface-engineering approach paves a new avenue to produce integrated strong-and-tough 2D nanohybrid materials that are useful in aerospace, artificial muscle, energy harvesting, tissue engineering and more.We have synthesized single crystals of a highly stable Cu-doped undeca-gold cluster protected by both triphenylphosphine (PPh3) and 2-pyridinethiol (-SPy) ligands, formulated as [Au11Cu1(PPh3)7(SPy)3]+. This cluster (Au11Cu1 NCs for short) has a metallic core of C3v Au@Au10 with the Cu atom capped on one of the nine triangular facets and it is triply-coordinated to three N atoms of the SPy ligands of which the sulfur atom simultaneously binds to three adjacent Au atoms via singly-coordinated S-Au bonds, respectively. The other seven gold atoms form a crown structure by a link of three orthogons with common sides and are protected by seven PPh3 ligands. Besides the well-organized coordination, this Au11Cu1 nanocluster is demonstrated to exhibit superatom stability of the metallic core within 8 valence electrons (assuming that the 3 electrophilic-SPy ligands capture 3 electrons from the metal center). More interestingly, this Au11Cu1 nanocluster shows interesting emissions in both ultraviolet visible (UV-Vis) and near infrared (NIR) regions, and the emissions display novel anti-Stokes up-conversion lasing characteristics. TD-DFT calculated UV-vis and emission spectra well reproduce the experimental results, shedding light on the nature of excitation states and underlying mechanism of electronic transitions between diverse energy levels of such a monolayer-protected bimetallic cluster.Near-infrared (NIR) light-induced photothermal cancer therapy using nanomaterials as photothermal agents has attracted considerable research interest over the past few years. As the key factor in photothermal therapy systems, a variety of photothermal agents have been developed. However, the exploration of novel photothermal therapy nanoplatforms with high NIR absorption remains a significant challenge, especially those working in both NIR-I and NIR-II windows. In this work, Bi19S27I3 nanorods with remarkably high absorption covering the whole visible light to the entire NIR-I and NIR-II regions have been successfully prepared through a facile solvothermal approach. The as-synthesized Bi19S27I3 nanorods have a high photothermal conversion efficiency of 42.7% at 808 nm (NIR-I) and 41.5% at 1064 nm (NIR-II), making them a promising candidate for photothermal therapy. Simufilam in vivo In vitro cell viability assay reveals that the Bi19S27I3 sample has good biocompatibility and exhibits significant cell-killing effect under NIR irradiation. In vivo anti-tumor experiments demonstrate that the tumor growth can be effectively inhibited by fatal hyperthermia ablation mediated by Bi19S27I3 nanorods under the irradiation of an 808 nm or 1064 nm laser. Therefore, this study should be primarily beneficial for the development of new materials for NIR photothermal therapy applications.A rhenium(i) naphthalimide complex [Re(CO)3(5-PAN)Cl] (Re(5-PAN); 5-PAN = 1-(1,10-phenanthroline)-4-nitro-naphthalimide) was synthesized, characterized, and evaluated as a photocatalyst for CO2 reduction. Characterization included use of MALDI-ToF mass spectrometry, FT-IR, RAMAN, 1H and 13C NMR, elemental analysis, electronic absorption and emission spectroscopy, single crystal X-ray diffraction, DFT and cyclic voltammetry. Photocatalytic (406 nm) reduction of 13CO2 to formate (H13COO) in the presence of this catalyst was tracked via13C NMR. Results support Re5-PAN (φ = 0.021) functioning as a catalyst for the reduction of CO2 (maximum turn-over 48-50 at 300 equiv. triethylamine as the sacrificial electron donor).Zinc-vanadium oxides have been attracting increasing consideration as anode materials for lithium/sodium-ion batteries (LIBs and SIBs) recently. Present applications are hampered by issues, including their inferior electric conductivity and enormous volume variation. Herein, nitrogen-doped carbon wrapped Zn3V3O8 (Zn3V3O8/NC) microspheres composed of abundant nanosheets were developed as an anode material by a self-assembly strategy and subsequent surface decoration. The resulting Zn3V3O8/NC porous hybrid exhibited a high specific capacity, impressive rate capability, and long-term cycling stability for both LIBs and SIBs. Notably, the superior electrochemical properties could be assigned to novel meso/microporous features, hybrid nitrogen-doped carbon, and mixed storage mechanisms.Copper containing materials are widely used in a range of catalytic applications. Here, we report the use of Cu K-edge high resolution XANES to determine the local site symmetry of copper ions during the thermal treatment of a Cu-Cr-Fe oxide catalyst. We exploited the Cu K-edge XANES spectral features, in particular the correlation between area under the pre-edge peak and its position to determine the local environment of Cu2+ ions. The information gained from this investigation rules out the presence of Cu2+ ions in a tetrahedral or square planar geometry, a mixture of these sites, or in a reduced oxidation state. Evidence is presented that the Cu2+ ions in the Cu-Cr-Fe oxide system are present in a distorted octahedral environment.Okadaic acid (OA) is produced by marine dinoflagellates and it can be easily accumulated in shellfish, causing intoxications when consumed by humans. Consequently, there is a need for sensitive, reliable and cost-effective methods to detect OA in real samples. In this work, we developed a novel and affordable microfluidic system to detect OA based on the protein phosphatase 1 inhibition colorimetric assay. This enzyme was immobilized in a microfluidic chamber by physisorption in an alumina sol-gel. The results show good enzyme stability over time when maintained at 4 °C. The developed system was sensitive for OA standard solutions, presenting a limit of detection (LOD) of 11.6 nM over a large linear range (43.4 to 3095.8 nM). Our method revealed an LOD as low as 0.2 μg kg-1 and a linear range between 1.47 and 506 μg kg-1 for extracted mussel matrix, detecting OA concentrations in contaminated mussels much lower than the regulated limit (160 μg kg-1). The enzyme stability and reusability along with the simplicity and low cost associated with microfluidics systems make this method very interesting from a commercial point of view.