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Deep eutectic-solvothermal synthesis of nanostructured ceria

Ceria is a technologically important material with applications in catalysis, emissions control and solid-oxide fuel cells. Nanostructured ceria becomes profoundly more active due to its enhanced surface area to volume ratio, reactive surface oxygen vacancy concentration and superior oxygen storage capacity. Here we report the synthesis of nanostructured ceria using the green Deep Eutectic Solvent

Atomistic modelling of scattering data in the ollaborative Computational Project for Small Angle Scattering (CCP-SAS)

The capabilities of current computer simulations provide a unique opportunity to model small-angle scattering (SAS) data at the atomistic level, and to include other structural constraints ranging from molecular and atomistic energetics to crystallography, electron microscopy and NMR. This extends the capabilities of solution scattering and provides deeper insights into the physics and chemistry o

Evidence of Lipid Exchange in Styrene Maleic Acid Lipid Particle (SMALP) Nanodisc Systems

Styrene-alt-maleic acid lipid particles (SMALPs) are self-assembled discoidal structures composed of a polymer belt and a segment of lipid bilayer, which are capable of encapsulating membrane proteins directly from the cell membrane. Here we present evidence of the exchange of lipids between such "nanodiscs" and lipid monolayers adsorbed at either solid-liquid or air-liquid interfaces. This behavi

Massive open online courses in chemistry : A comparative overview of platforms and features

Open-access, online educational platforms launched in the last decade are receiving growing attention from both academia and the general public. A special class of such courseware known as MOOCs (massive open online courses) allows enrollment of up to hundreds of thousands of students from all over the world. This report reviews and compares currently available chemistry MOOCs as well as other Web

Broad spectral photocurrent enhancement in Au-decorated CdSe nanowires

Metal-semiconductor hybrid nanostructures promise improved photoconductive performance due to plasmonic properties of the metal portions and intrinsic electric fields at the metal-semiconductor interface that possibly enhance charge separation. Here we report gold decorated CdSe nanowires as a novel functional material and investigate the influence of gold decoration on the lateral facets on the p

A new route to produce efficient surface-enhanced Raman spectroscopy substrates : Gold-decorated CdSe nanowires

Surface-enhanced Raman spectroscopy is a popular tool for the detection of extremely small quantities of target molecules. Au nanoparticles have been very successful in this respect due to local enhancement of the light intensity caused by their plasmon resonance. Furthermore, Au nanoparticles are biocompatible, and target substances can be easily attached to their surface. Here, we demonstrate th

Chemically induced self-assembly of spherical and anisotropic inorganic nanocrystals

The self-assembly of inorganic nanoparticles is a research area of great interest aiming at the fabrication of unique mesostructured materials with intrinsic properties. Although many assembly strategies have been reported over the years, chemically induced self-assembly remains one of the dominant approaches to achieve a high level of nanoparticle organization. In this feature article we will rev

Synthesis and characterization of azidoalkyl-functionalized gold nanoparticles as scaffolds for "click"-chemistry derivatization

We demonstrate how water-soluble gold nanoparticles prepared by the citrate reduction method can be functionalized with 11-azidoundecane-1-thiol in a single-step procedure, which combines phase transfer and ligand exchange. The advantages of our method include high reproducibility, low cost of gold nanoparticle production, and rapid and clean ligand exchange, with minimal intermediate steps and no

Assembly of shape-controlled nanocrystals by depletion attraction

Recently (Baranov et al., Nano Lett., 2010, 10, 743) we demonstrated that depletion attraction between semiconductor nanorods in solution can be employed for both their self-assembly and their separation from spherical nanoparticles. Here we show that depletion attraction can be used to fabricate binary superlattices of nanorods and 3D networks of octapod/tetrapod-shaped nanocrystals.

Phototransport in networks of tetrapod-shaped colloidal semiconductor nanocrystals

Tetrapod-shaped CdSe(core)/CdTe(arms) colloidal nanocrystals, capped with alkylphosphonic acids or pyridine, were reacted with various small molecules (acetic acid, hydrazine and chlorosilane) which induced their tip-to-tip assembly into soluble networks. These networks were subsequently processed into films by drop casting and their photoconductive properties were studied. We observed that films

Assembly of colloidal semiconductor nanorods in solution by depletion attraction

Arranging anisotropic nanoparticles into ordered assemblies remains a challenging quest requiring innovative and Ingenuous approaches. The variety of interactions present in colloidal solutions of nonspherical inorganic nanocrystals can be exploited for this purpose. By tuning depletion attraction forces between hydrophobic colloidal nanorods of semiconductors, dispersed in an organic solvent, the

Synthesis of cobalt-containing nanoparticles by cobalt formate thermolysis in hydrocarbon oil without stabilizing ligands

A simple and available method is proposed for the synthesis of cobalt-containing nanoparticles. This method comprises cobalt formate thermolysis in hydrocarbon oil without extra stabilizing ligands. The size, composition, and structure of the nanoparticles are determined by transmission electron microscopy, X-ray powder diffraction, and electron diffraction. The average particle size is 10-14 nm.

Synthesis of flexible, ultrathin gold nanowires in organic media

Gold nanoparticles are very interesting because of their potential applications in microelectronics, optical devices, analytical detection schemes, and biomedicine. Though shape control has been achieved in several polar solvents, the capability to prepare organosols containing elongated gold nanoparticles has been very limited. In this work we report a novel, simplified method to produce long, th

Organization of magnetic/noble metal heterostructures by an applied external magnetic field

This paper describes the synthesis of binary nanoparticles consisting of a noble metal and a magnetic component. These heterostructures were produced by a seeded-growth approach in aqueous solution. FePt nanoparticles, as the magnetic component, were first synthesized in an organic medium, subsequently transferred into water, and finally used as seeds for the growth of the noble metal Au. This pro

Länsstyrelsen och o-djuret. : Lek som strategi i fridlysningen av Storsjöodjuret 1985-2005

In 1985 the County Administrative Board of Jämtland initiated a process to protect Storsjöodjuret (the Great Lake Monster). As other famous cryptids, the Monster has become a valuable resource in the process of cultural heritage, marketing and tourism. We apply Bateson’s theories of play (1972) and Goffman’s concept of frame (1974) to show how play offers a metacommunicative strategy to circumvent

Utgrävningarna av gravfältet i Vätteryd

Mellan åren 1955 och 1957 utförde Märta Strömberg (sedermera professor i arkeologi) och Rolf Petré (som senare blev fil. lic. i arkeologi) arkeologiska undersökningar av Vätterydsgravfältet i norra Mellby socken (L1990:1893 / Norra Mellby 1:1) ...