Solvent-induced aggregation of regioregular head-to-tail poly(3-alkylthiophene)s (PATs) have been studied by means of AFM and UV−vis spectroscopy. In hexane, which is a good solvent for alkyl side chains but poor for polythiophene backbones, PAT molecules undergo ordered main-chain collapse driven by solvophobic interaction. Well-pronounced concentration-independent red shift of λ max and good resolved fine vibronic structure in the electronic absorption spectra observed upon addition of hexane indicate that planarization occurs on the singlemolecule level. A helical conformation of the man chain of PATs with 12 thiophene rings per each helical turn has been proposed. At the higher concentration of PATs the collapsed molecules undergo unexpected one-dimensional aggregation. Length of the particles varies from several nanometers to several hundreds nanometers and can be easily adjusted by the solvent composition or concentration of PATs.

The electrical impedance of quartz crystals was measured during electropolymerization of poly (2,2Ј-bithiophene) ͑PBT͒ and poly-͑3,4-ethylenedioxythiophene͒ ͑PEDT͒ from acetonitrile and propylene carbonate. Due to the viscoelastic behavior and the high surface roughness, application of the Sauerbrey equation to relate frequency shifts to mass changes leads to systematic errors. A novel procedure is presented to calculate the mass changes, the viscoelastic properties ͑complex shear modulus͒, and the surface roughness of the conducting polymer layers from the shift of the resonance curve of the quartz crystal. The dependence of the surface morphology of PEDT and PBT on the preparation conditions could be monitored in situ. The values of the complex shear moduli show that these polymers have rubber-like behavior. The damping increase of the quartz at the initial stages of the polymer deposition is mainly a surface roughness effect. As the polymer thickness increases, internal friction ͑viscoelasticity͒ also begins to contribute to the damping.

An agent-based model for simulating the in vitro growth of Beta vulgaris hairy root cultures is described. The model fitting is based on experimental results and can be used as a virtual experimentator for root networks. It is implemented in the JAVA language and is designed to be easily modified to describe the growth of diverse biological root networks. The basic principles of the model are outlined, with descriptions of all of the relevant algorithms using the ODD protocol, and a case study is presented in which it is used to simulate the development of hairy root cultures of beetroot (Beta vulgaris) in a Petri dish. The model can predict various properties of the developing network, including the total root length, branching point distribution, segment distribution and secondary metabolite accumulation. It thus provides valuable information that can be used when optimizing cultivation parameters (e.g., medium composition) and the cultivation environment (e.g., the cultivation temperature) as well as how constructional parameters change the morphology of the root network. An image recognition solution was used to acquire experimental data that were used when fitting the model and to evaluate the agreement between the simulated results and practical experiments. Overall, the case study simulation closely reproduced experimental results for the cultures grown under equivalent conditions to those assumed in the simulation. A 3D-visualization solution was created to display the simulated results relating to the state of the root network and its environment (e.g., oxygen and nutrient levels).

An ultra-compact, portable solid oxide fuel cell (SOFC) system in the 100 Watt class is presented which is based on multilayer and ceramic technology and that runs on conventional fuels. The active SOFC system core within the insulation is smaller than 1 liter. The eneramic® system is designed for LPG mixtures and operates on ethanol as well. Due to its good thermal packaging the system achieves a gross efficiency of 33% and net efficiency up to 24% when commercial BoP components are applied.

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