Emerging Artificial Societies Through Learning

The NewTies project is implementing a simulation in which societies of agents are expected to de-velop autonomously as a result of individual, population and social learning. These societies are expected to be able to solve environmental challenges by acting collectively. The challenges are in-tended to be analogous to those faced by early, simple, small-scale human societies. This report on work in progress outlines the major features of the system as it is currently conceived within the project, including the design of the agents, the environment, the mechanism for the evolution of language and the peer-to-peer infrastructure on which the simulation runs

Structural investigation of mechanically activated ZnO powder

Commercially available ZnO powder was mechanically activated in a planetary ball mill. In order to investigate the specific surface area, pore volume and microstructure of non-activated and mechanically activated ZnO powders the authors performed N-2 physisorption, SEM and TEM. Crystallite size and lattice microstrain were analyzed by X-ray diffraction method. XRD patterns indicate that peak intensities are getting lower and expend with activation time. The reduction in crystallite size and increasing of lattice microstrain with prolonged milling time were determined applying the Rietveld's method. The difference between non-activated and the activated powder has been also observed by X-ray photoelectron spectroscopy (XPS). XPS is used for investigating the chemical bonding of ZnO powder by analyzing the energy of photoelectrons. The lattice vibration spectra were obtained using Raman spectroscopy. In Raman spectra some changes along with atypical resonant scattering were noticed, which were caused by mechanical activation

Optical control over photoconductivity in polyferrocenylsilane films

We report the study and elucidate the origin of the photoconductivity of polyferrocenylsilanes achieved through photooxidation performed by ultraviolet irradiation in the presence of chloroform. The persistence over months of the changes in the optoelectronic properties allowed more detailed studies of the charge photogeneration process. The photocurrentspectrum mimics that of the absorption indicating that the photooxidized material is not a mechanical mixture of oxidized and unoxidized polymer units. Photomodulation spectroscopy revealed the existence of long-lived photoexcited states with a lifetime in the millisecond range. They have been interpreted as trapped excitons at the oxidized sites where the polymer is deformed due to the presence of the chloroform derived counter ions. Because of the relatively long lifetime of the trapped excitons they can dissociate and the formed charge carriers can be separated in an externally applied electric field. The effect of the polymer chain deformation around the oxidized unit extends over the neighboring polymer units. In light of the potential applications of this class of polymers in various electronic and photonic devices, the clarification of such a basic process as the photocurrent generation will be a key factor for further technological development