Search results for "surface"
showing 10 items of 9345 documents
A plasma protein corona enhances the biocompatibility of Au@Fe3O4 Janus particles
2015
AbstractAu@Fe3O4 Janus particles (JPs) are heteroparticles with discrete domains defined by different materials. Their tunable composition and morphology confer multimodal and versatile capabilities for use as contrast agents and drug carriers in future medicine. Au@Fe3O4 JPs have colloidal properties and surface characteristics leading to interactions with proteins in biological fluids. The resulting protein adsorption layer (“protein corona”) critically affects their interaction with living matter. Although Au@Fe3O4 JPs displayed good biocompatibility in a standardized in vitro situation, an in-depth characterization of the protein corona is of prime importance to unravel underlying mecha…
Segregation in Drying Binary Colloidal Droplets
2019
When a colloidal suspension droplet evaporates from a solid surface, it leaves a characteristic deposit in the contact region. These deposits are common and important for many applications in printing, coating, or washing. By the use of superamphiphobic surfaces as a substrate, the contact area can be reduced so that evaporation is almost radially symmetric. While drying, the droplets maintain a nearly perfect spherical shape. Here, we exploit this phenomenon to fabricate supraparticles from bidisperse colloidal aqueous suspensions. The supraparticles have a core-shell morphology. The outer region is predominantly occupied by small colloids, forming a close-packed crystalline structure. Tow…
Coarse-Graining Intermolecular Interactions in Dispersions of Highly Charged Colloids
2012
International audience; Effective pair potentials between charged colloids, obtained from Monte Carlo simulations of two single colloids in a closed cell at the primitive model level, are shown to reproduce accurately the structure of aqueous salt-free colloidal dispersions, as determined from full primitive model simulations by Linse et al. (Linse, P.; Lobaskin, V. Electrostatic Attraction and Phase Separation in Solutions of Like-Charged Colloidal Particles. Phys. Rev. Lett.1999, 83, 4208). Excellent agreement is obtained even when ion-ion correlations are important and is in principle not limited to spherical particles, providing a potential route to coarse-grained colloidal interactions…
Control of Morphology and Corona Composition in Aggregates of Mixtures of PS-b-PAA and PS-b-P4VP Diblock Copolymers: Effects of Solvent, Water Conten…
2014
The morphologies and corona compositions in aggregates of mixtures of PS-b-PAA and PS-b-P4VP diblock copolymers are influenced by controllable assembly parameters such as water content, block copolymer molar ratios, and solvent effects as well as the hydrophilic block lengths and block length ratios. All these factors can affect the morphology of the aggregates as well as their corona composition, the latter especially in vesicles, where two interfaces are involved. The morphologies and corona compositions of the aggregates were investigated by transmission electron microscopy and electrophoretic mobility, respectively. They depend, to a large extent, on the solubility of P4VP and PAA in th…
Control of Corona Composition and Morphology in Aggregates of Mixtures of PS-b-PAA and PS-b-P4VP Diblock Copolymers: Effects of pH and Block Length
2014
The corona compositions and morphologies in aggregates of mixtures of amphiphilic polystyrene-block-poly(acrylic acid) (PS-b-PAA) and polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymers are influenced by controllable assembly parameters such as the hydrophilic block length and solution pH. The morphologies and corona compositions of the aggregates were investigated by transmission electron microscopy and electrophoretic mobility, respectively. When mineral acids or bases are present during aggregate formation, they can exert a strong influence on the corona composition. Morphology changes were also seen with changing pH, as well as changes in corona composition, specifica…
Effect of bisphenol A on ameloblasts and tooth enamel mineralization
2011
Effect of bisphenol A on ameloblasts and tooth enamel mineralization. Journées de l’école doctorale
Idiosyncratic responses to simulated herbivory by root fungal symbionts in a subarctic meadow
2021
Plant-associated fungi have elementary roles in ecosystem productivity. There is little information on the interactions between arbuscular mycorrhizal (AM) fungal symbiosis, fine endophytic (FE) and dark septate endophytic (DSE) fungi, and their host plants in cold climate systems. In particular, the environmental filters potentially driving the relative abundance of these root symbionts remain unknown. We investigated the interlinkage of plant and belowground fungal responses to simulated herbivory (clipping, fertilization, and trampling) in a subarctic meadow system. AM and FE frequency in the two target plant roots, Potentilla crantzii and Saussurea alpina, was unaffected by simulated he…
Forensic tools for the diagnosis of electrocution death: Case study and literature review
2018
Diagnosis of death by electrocution may be difficult when electric marking is not visible or unclear. Accordingly, the body of a man who appeared to have died from accidental electrocution was carefully forensically analysed. Macroscopic and microscopic analysis of the current mark was carried out using a variable-pressure scanning electron microscope equipped with energy dispersive X-ray microanalyser to highlight skin metallisation, indicating the presence of iron and zinc. The histological findings of electrocution myocardial damage were supported by the results of biochemical analysis which demonstrated the creatine kinase-MB and cardiac troponin I elevation. The effects of electric cu…
Water dissociation and water-gas shift energetics on MgO, MgO/Ag and Au/MgO/Ag surfaces
2011
Water dissociation and the energetics of the WGS reaction on a bulk MgO, an Ag supported MgO thin film and Au/MgO/Ag surfaces is studied based on the density functional theory. The literature results for water splitting on MgO and MgO/Ag surfaces with a step type defect are repeated and further analysis on the origin of the energetically favored dissociative water adsorption are made. The reactivity towards water dissociation on the stepped MgO and MgO/Ag surfaces is attributed to four contributing factors: 1. The change in the interlayer distance of the surface in dissociative adsorption is diminished on the stepped surfaces compared to the flat surfaces. On the flat surfaces the dissociat…
Wykorzystanie energii wiatru występującego w warstwie przygruntowej oraz architektonicznej
2016
W pracy przedstawiono wyniki analiz możliwości wykorzystania energii wiatru za pomocą mikro turbin wiatrowych. Przeanalizowano możliwość wykorzystania energii wiatru występującego w warstwie przygruntowej oraz architektonicznej. Zaproponowano zastosowanie układu mikroelektrowni wiatrowej o mocy 2 kW na potrzeby pojedynczego gospodarstwa domowego.Określono opłacalność zastosowania tego typu mikroelektrowni w warunkach wietrzności panujących w Opolu.