Hydrophobization of multilayered film containing layer-by-layer assembled nanoparticle by Nafion adsorption

Summary The multilayered film on a glass substrate, assembled from cationic poly(ethyleneimine) (PEI), anionic nano-sized polystyrene (PS) latex particle and cationic PEI or poly(allylamine hydrochloride) (PAH) layer was prepared by using the layer-by-layer (LbL) technique. Hydrophobization was carried out by immersing the film in Nafion solution. The hydrophobicity with high contact angle value was achieved by adjusting deposition ionic strength and ratio of water/ethanol of Nafion solution. The existence of PS particles in the LbL film significantly enhanced hydrophobicity of the film surface.     

Radiation damping in metal nanoparticle pairs

The radiation damping rate of plasmon resonances in pairs of spherical gold nanoparticles is calculated. The radiative line width of the plasmon resonance indicates significant far-field coupling between the nanoparticles over distances many times the particle diameter. The radiation damping of the coupled particle-plasmon mode alternates between superradiant and subradiant behavior when the particle spacing is varied. At small particle spacings where near-field coupling occurs, the radiation damping rate lies far below that of an isolated particle.     

MESHMdl event spaces — A coordination middleware for self-organizing applications in ad hoc networks

Mobile ad hoc networks (MANETs) are gaining importance as a promising technology for flexible, proximity-based, mobile communication. However, the inherent dynamics of MANETs imposes strong limitations on the design of distributed applications. They need to be able to adapt to changing conditions quickly and organize themselves in terms of component placement and communication habits. In this paper, we present MESHMdl, a middleware that provides a high level of awareness and decoupling for application components to make them more flexible and adaptable. We focus on the Event Space as the central communication medium of MESHMdl. The Event Space offers a simple, unified communication interface for inter-agent communication as well as for communication with the middleware and resource access. Furthermore, it serves as a means for flexibly extending a MESHMdl daemon. We investigate the performance of the Event Space on different mobile devices and show that it is superior to comparable systems.     

Disk-Elektrophorese der wasserl?slichen Proteine einiger Weizensorten

Die beschriebene Methode erlaubt eine zuverlässige Erkennung der Sorte Kranich aus insgesamt 9 untersuchten Weizensorten innerhalb von 5 Stunden.     

Energy in context: A multicriteria model for building design

A model is proposed for the representation and comparison of design alternatives which puts energy efficiency in a context of performances in other criteria. The model utilizes notions of decision and performance spaces and multicriteria Pareto optimization. A simple example is described.     

Interaction of amphiphilic polymers with model membranes

The lipid bilayers of cell membranes are usually connected to two types of biopolymers: the cytoskeleton and the glycocalix. These structures are not only responsible for the stabilization of the lipid bilayer, they also alter the surface properties of the cells. Among the various attempts to mimick membrane properties using polymeric systems(¹), one method is the fixation of amphiphilic polymers via hydrophobic anchor groups to lipid bilayers. In the experiments reported here the influence of amphiphilic polymers on the morphology of giant unilamellar liposomes has been investigated. Therefore a series of amphiphilic polyvinylpyrrolidone and dextran derivatives has been synthesized. The fixation of these polymers to the liposomal membranes could be shown with a fluorescence-labelled derivative by using epifluorescence microscopy. The polymer-membrane interaction caused by the insertion of the anchor groups leads to drastic morphological changes in this model membrane system. The exclusive interaction with the outer membrane of multilamellar liposomes could be demonstrated by freeze fracture electron microscopy. In addition, the anchoring of a natural capsular polysaccharide in liposomes has been proven by immunofluorescence. In these experiments, also a clustering (patching) of the antigen caused by the binding of the antibody could be observed.