Soelberglund1772

Based on multivariate analysis (PCA) of the standardized database (14 elements and PM2.5), a significant contribution of different sources and processes was identified, i.e. local traffic emission, local/regional coal/oil burning in power plants and domestic heating units, industrial activities, petrochemical industry and maritime transport. #link# The Cu/Fe ratios revealed that both local traffic and brake-wear emission considerably influenced the chemical composition of PM2.5. In addition, the results of the V/Ni ratio suggested local mixed industrial sources (petrochemical refinery and industrial plants) with possible contributions from the port area and shipping activities to the total PM2.5 loadings. The local ship emission was more pronounced during the summer period.Given the prevalence of fluorescence spectroscopy in biological systems, and the prevalence of pterin derivatives throughout biological systems, presented here is an assessment of the two-photon absorption spectroscopy as it applies to a range of the most commonly studied pterin derivatives. QR-CAMB3LYP//ccpVTZ calculations suggest that the use of two-photon spectroscopic methods would enable a more capable differentiation between closely related derivatives in comparison to the one-photon spectra, which show minimal qualitative deviation. Study of short tail derivatives shows that, in most cases, two-photon accessible states solely involve the π* LUMO as the particle orbital, with biopterin, neopterin, and 6-(hydroxymethyl)pterin presenting exceptional potential for targetting. Investigation of derivatives in which the tail contains an aromatic ring resulted in the observation of a series of two-photon accessible states involving charge transfer from the tail to the pterin moiety, the cross sections of which are highly dependent on the adoption of a planar geometry. The observation of these states presents a novel method for tracking the substitution of biologically important molecules such as folic acid and 5-methenyltetrahydrofolylpolyglutamate.Incorporation of minimally perturbative vibrational probes into proteins allows combination of the femtosecond time resolution of two dimensional infrared (2D-IR) spectroscopy with a spatial resolution on the level of single side chains. Here, we apply the thiocyanate (-SCN) label introduced by the cyanylation of cysteine to probe local dynamics in the photo-switchable protein PYP. We incorporated the -SCN label into five positions of the protein structure including PYP's core region, its solvent exposed surface and the chromophore-binding pocket. The analysis of -SCN's time dependent 2D-IR lineshape provides insight into the timescales and amplitudes of the dynamics in the label's protein and solvent microenvironment. We present a detailed analysis of the local protein dynamics found at all five labelling positions in PYP's dark state (pG). Absorption of a blue photon triggers the isomerisation of PYP's chromophore and eventually leads to an overall reorganisation of the protein structure, where PYP ends up in a less structured signalling state pB. Employing 2D-IR spectroscopy also on the signalling state allows assessment of the change of local dynamics compared to the pG state.A novel nanopipette electrode was facilely constructed for the detection of ˙OH based on the inner surface wettability. The nanopipettes with excellent analytical performance were empolyed for in situ detection of ˙OH changes induced by mitochondrial oxidative stress and further utilized to study the association of ˙OH with Alzheimer's disease.Metal-organic frameworks (MOFs) are a good platform for the fabrication of single atomic site catalysts (SACs) due to their large specific surface area, rich pore structure, large number of unsaturated coordination metal sites and their intriguing and controllable structures. The influencing factors of each strategy used to synthesize SACs based on MOFs, such as the finetuning ligand strategy, heteroatom doping (N, P, S) strategy, space restriction strategy, bimetallic strategy, metal cluster defect strategy, substrate to capture strategy, and various post-treatment strategies have not been discussed. Here, we will discuss the influencing factors of each strategy and the relationship between the different methods, which are used to synthesize SACs based on MOFs.We show that magnetic resonance imaging (MRI) can be used to visualize the spatiotemporal dynamics of iron oxide nanoparticle growth within a hydrogel network during in situ coprecipitation. The synthesis creates a magnetic nanoparticle loaded polymer gel, or magnetogel. During in situ coprecipitation, iron oxide nanoparticles nucleate and grow due to diffusion of a precipitating agent throughout an iron precursor loaded polymer network. The creation of iron oxide particles changes the magnetic properties of the gel, allowing the synthesis to be monitored via magnetic measurements. Formation of iron oxide nanoparticles generates dark, or hypointense, contrast in gradient echo (GRE) images acquired by MRI, allowing nanoparticle nucleation to be tracked in both space and time. We show that the growth of iron oxide nanoparticles in the hydrogel scaffold is consistent with a simple reaction-diffusion model.The modern world has seen exposure of bacterial communities to toxic metals at selective levels. This manifests itself both intentionally, through medicines and un-intentionally through waste streams. There is growing concern that selective exposure to metals may be linked to microbial resistance to antibiotics. For a microbe to become resistant to a specific metal it must first come in contact with it. The transition metal copper has the ability to enter bacterial cells without need for a copper specific uptake mechanism. Copper is commonly used as an antimicrobial in the healthcare industry, consumer products and as a growth promoter of livestock in the agricultural sector. Here we report a study into the uptake of different organic and inorganic sources of copper. A whole-cell bacterial biosensor was developed to quantify the specific uptake of copper from various sources. Furthermore, a cell-free sensor was utilized to investigate the response to copper sources when uptake is eliminated as a factor. link2 The data within suggest inorganic copper to have greatly reduced uptake compared to organic sources and that there is significant difference between copper oxides, Cu2O and CuO.The results of X-ray diffraction studies of the Gd(Mg0.95-x,ZnxMn-0.05)B5O10 down-converting phosphor as a function of Mg-Zn composition are presented. The lattice parameters and unit cell volumes of GdMg0.95-xZnxMn0.05B5O10 pentaborates are examined. The relationships between the structure and optical properties of these materials are explicated based on the results of theoretical calculations of the energy structure. The effect of pressure on the luminescence of Mn2+ in this system was studied up to ca. 32 GPa. The observed quenching of Mn2+ luminescence is due to the crossing of the emitting 4T1g level with the non-emitting 2T2g state. This crossing sets a long-wavelength limit on the possibility of observing the emission of Mn2+ ions, which is around 850 nm.Silicon anodes are promising for high energy batteries because of their excellent theoretical gravimetric capacity (3579 mA h g-1). However, silicon's large volume expansion and poor conductivity hinder its practical application; thus, binders and conductive additives are added, effectively diluting the active silicon material. To address this issue, reports of 2D MXene nanosheets have emerged as additives for silicon anodes, but many of these reports use high MXene compositions of 22-66 wt%, still presenting the issue of diluting the active silicon material. Herein, GW441756 order examines the question of what minimal amount of MXene nanosheets is required to act as an effective additive while maximizing total silicon anode capacity. A minimal amount of only 4 wt% MXenes (with 16 wt% sodium alginate and no carbon added) yielded silicon anodes with a capacity of 900 mA h gSi-1 or 720 mA h gtotal-1 at the 200th cycle at 0.5 C-rate. Further, this approach yielded the highest specific energy on a total electrode mass basis (3100 W h kgtotal-1) as comapared to other silicon-MXene constructs (∼115-2000 Wh kgtotal-1) at a corresponding specific power. The stable electrode performance even with a minimal MXene content is attributed to several factors (1) highly uniform silicon electrodes due to the dispersibility of MXenes in water, (2) the high MXene aspect ratio that enables improved electrical connections, and (3) hydrogen bonding among MXenes, sodium alginate, and silicon particles. All together, a much higher silicon loading (80 wt%) is attained with a lower MXene loading, which then maximizes the capacity of the entire electrode.A transition metal phosphide is an excellent candidate for supercapacitors due to its superior electrical conductivity and high theoretical capacity. In addition, compared with traditional 3D nano-materials, 2D nanosheets possess a greater specific surface area and shorter electron transport distance. In this study, a reasonable approach is proposed for the synthesis of ZIF-67 nanosheets on nickel foam with subsequent phosphorization by chemical vapor deposition (CVD) to obtain flake-like CoP combined with Ni2P (NCP/NF), in which nickel foam serves as the current collector as well as the resource of Ni to form Ni2P. Benefiting from the nanosheet array of CoP, the NCP/NF can improve the capacity of Ni2P from 0.57 C cm-2 to 1.43 C cm-2 at 1 mA cm-2. Furthermore, the NPC/NF/reduced graphene oxide (RGO) asymmetric supercapacitor (ASC) shows an energy density of 26.9 μW h cm-2 at a power density of 0.896 mW cm-2, and excellent cycling performance with a capacity retention of 93.75% after 5000 cycles at 10 mA cm-2.Transition metal oxides (TMOs) are regarded as important materials due to their wide applications in catalysis, sensors, energy storage and conversion devices owing to their advantages of facile synthesis, low cost, and high activity. Here we develop a direct deep eutectic solvent (DES) calcining method to prepare low-dimensional and highly active TMOs for the electrochemical oxygen evolution reaction (OER). link3 Glucose monohydrate and urea can form a glucose-urea DES, which was calcined under a N2 atmosphere to produce 2D N,O-doped graphene. When metal precursors were introduced into the glucose-urea DES and calcined together, the TMOs were templated by graphene flakes and exhibited low-dimensional morphologies. With this method, 2D nanonet-shaped La0.5Sr0.5Co0.8Fe0.2O3 (LSCF), Co3O4, NiCo2O4, and RuO2 and 1D nanowire-shaped Ba0.5Sr0.5Co0.8Fe0.2O3 (BSCF) were readily synthesized, and their thickness and porosity can be conveniently tuned by adjusting the concentrations of metal salts. Our nanostructured TMOs were further applied for the OER, and they showed quite competitive activities over their counterparts obtained from other methods. The 2D porous LSCF20-DES exhibited the largest specific surface area (28.9 m2 g-1) and the highest OER electrocatalytic activities (0.304 V overpotential at a current density of 10 mA cm-2). These results demonstrate that the DES calcining method is a comprehensive approach to synthesize hierarchical TMOs as highly active OER catalysts.