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The 14th Conference of the European Colloid and Interface Society

Plastic Solar Cells

Recent developments in conjugated-polymer-based photovoltaic elements are reviewed. The photophysics of such photoactive devices is based on the photo-induced charge transfer from donor-type semiconducting conjugated polymers to acceptor-type conjugated polymers or acceptor molecules such as Buckminsterfullerene, C60.…

A new algorithm for dissipative particle dynamics

Analogies between dissipative particle dynamics (DPD) and stochastic dynamics are exploited to derive a new algorithm for DPD with an improved temperature control, without recursion or tuneable parameters.

The Surface Chemistry of Imogolite

Abstract Imogolite is a tubular aluminosilicate which is common in Andosols and Spodosols. The high pH at point-of-zero charge at the outer parts of the tube and the anomalously high chloride adsorption of imogolite suggested that there may be structural charge associated with this mineral. The structural charge may a…

Carrier-induced ferromagnetism inp−Zn1−xMnxTe

We present a systematic study of the ferromagnetic transition induced by the holes in nitrogen doped ${\mathrm{Zn}}_{1\ensuremath{-}x}{\mathrm{Mn}}_{x}\mathrm{Te}$ epitaxial layers, with particular emphasis on the values of the Curie-Weiss temperature as a function of the carrier and spin concentrations. The data are…

Thermal Conductivity of β‐Si 3 N 4 : III, Effect of Rare‐Earth (RE = La, Nd, Gd, Y, Yb, and Sc) Oxide Additives

β‐Si 3 N 4 ceramics sintered with a series of rare‐earth (RE = La, Nd, Gd, Y, Yb and Sc) oxide additives were fabricated by hot pressing and subsequent annealing. Their microstructures, lattice oxygen contents, and thermal conductivities were evaluated. Mean grain size increased, while lattice oxygen content decreased…

Efficient neodymium-doped glass-ceramic fiber laser and amplifier

We report an efficient glass-ceramic fiber laser and show that its slope efficiency (~30%) is not compromised by the presence of Nd-doped fluoride crystals embedded within the core of the single-mode optical fiber. In contrast, the spectroscopy (fluorescence and gain spectrum) of the Nd(3+) ions is dramatically change…

Analytical TEM study on the dispersion of Au nanoparticles in Au/TiO 2 catalyst prepared under various temperatures

Abstract Transmission electron microscopy (TEM) observations were made for Au/TiO 2 catalysts prepared by calcination in air at different temperatures from room temperature to 873 K in order to study the growth process of Au particles over the surface of TiO 2 . Many Au clusters with diameters of ∼1 nm were observed o…

Atomistic Simulation of Dopant Incorporation in Barium Titanate

The results of an atomistic simulation study on the incorporation of ions of the first series of transition metals (Cr 3+ , Cr 4+ , Fe 2+ , Fe 3+ , Co 2+ , Co 3+ , Ni 2+ , and Ni 3+ ), Y 3+ , and ions of the lanthanide series (Er 3+ , Gd 3+ , Tb 3+ , Pr 3+ , Pr 4+ , and La 3+ ) in the BaTiO 3 lattice are presented and…

Density-functional theory of elastically deformed finite metallic system: Work function and surface stress

We study the external strain effect on the surface properties of simple metals within the framework of a modified stabilized jellium model. We derive the equations for the stabilization energy of the deformed Wigner-Seitz cells considered as a function of the bulk electron density and the given deformation. The result…

Exponential decay properties of Wannier functions and related quantities

The spatial decay properties of Wannier functions and related quantities have been investigated using analytical and numerical methods. We find that the form of the decay is a power law times an exponential, with a particular power-law exponent that is universal for each kind of quantity. In one dimension we find an e…

Violation of the fluctuation-dissipation relation during the formation of a colloidal glass

The relationship between the conductivity and the polarization noise is measured in a colloidal glass as a function of frequency in the range 1 Hz-40 Hz. It is found that at the beginning of the transition from a fluid-like sol to a solid-like colloidal glass the fluctuation-dissipation relation is strongly violated.…

Triangular CdS Nanocrystals: Structural and Optical Studies

CdS nanostructures with high crystallinityare widely investigated for their semiconductor properties. This work focuses on the preparation and properties of equilateral-triangular nanocrystals made by colloidal self-assembly. The picture shows the results of high-resolution transmission electron microscopy imaging of…

Thin-Film Formation of Calcium Carbonate Crystals: Effects of Functional Groups of Matrix Polymers

We report on the preparation of the thin films of calcium carbonate (CaCO 3 ) crystals on solid matrixes, i.e., cellulose, chitosan, and chitin in the presence of an acidic macromolecule. The crystal growth from CaCO 3 solution containing poly(acrylic acid) as a soluble acidic polymer results in the formation of CaCO…

Strain-dependent local empirical pseudopotentials for lattice mismatched III-V semiconductors, their alloys, heterostructures and nanostructures

For the latest EPM potentials, please see appendix A in Physical Review B, 59, 15270 (1999)

A Novel Approach to Functionalized Nanoparticles: Self-Crosslinking of Macromolecules in Ultradilute Solution

The intermolecular self-crosslinking of functionalized macromolecules under ultra-dilute conditions (see Figure) provides a versatile approach to the preparation of nanoparticles with very small sizes. The size and the chemical nature of the particles are easily controlled and the use of particles produced in this way…

Stability of MRI Paramagnetic Contrast Media

RATIONALE AND OBJECTIVES: The suitability of paramagnetic complexes as magnetic resonance contrast agents depends on various factors such as their relaxivity, stability, selectivity, and the inertness toward transmetallation by endogenous ions. The transmetallation of a series of 18 gadolinium complexes by the Zn2+ io…

Self-Assembly of Monodispersed Spherical Colloids into Complex Aggregates with Well-Defined Sizes, Shapes, and Structures

The self-assembly of polystyrene beads into a variety of polygonal and polyhedral clusters is reported. The Figure shows a schematic illustration of the procedure used to form these well-defined clusters under physical confinement. These aggregates will be useful as new types of building blocks in hierarchical self-as…

Complex Magnetism and Magnetic Structures of the Metastable HoMnO3 Perovskite

The magnetic properties and the low-temperature magnetic structures of the orthorhombic perovskite HoMnO 3 (space group Pnma ) have been studied on polycrystalline samples by magnetization, specific heat, and neutron diffraction measurements. By cooling, HoMnO 3 exhibits three singularities at T N = 41 K, T ≈ 26 K, an…

Antimicrobial properties of porphyrins

A large number of natural and synthetic porphyrins of diverse chemical compositions and characteristics can be isolated from nature or synthesised in the laboratory. Antimicrobial and antiviral activities of porphyrins are based on their ability to catalyse peroxidase and oxidase reactions, absorb photons and generate…