Hydrogen and Carbon Nanotubes from Pyrolysis-Catalysis of Waste Plastics: A Review

More than 27 million tonnes of waste plastics are generated in Europe each year representing a considerable potential resource. There has been extensive research into the production of liquid fuels and aromatic chemicals from pyrolysis-catalysis of waste plastics. However, there is less work on the production of hydrogen from waste plastics via pyrolysis coupled with catalytic steam reforming. In this paper, the different reactor designs used for hydrogen production from waste plastics are considered and the influence of different catalysts and process parameters on the yield of hydrogen from different types of waste plastics are reviewed. Waste plastics have also been investigated as a source of hydrocarbons for the generation of carbon nanotubes via the chemical vapour deposition route. The influences on the yield and quality of carbon nanotubes derived from waste plastics are reviewed in relation to the reactor designs used for production, catalyst type used for carbon nanotube growth and the influence of operational parameters

Fabrication and characterisation of miniature mckibben actuators

This paper investigates the development of miniature compliant actuators that can generate high forces for applications where machines interact directly with human beings such as service robots, prostheses and instruments for surgery. During this research, pneumatic McKibben actuators have been miniaturized to an outside diameter of 1.5 mm and a length of 22 mm to 62 mm. These actuators are able to achieve forces of 6 N and strains up to about 15 % at a supply pressure of 10 bar. The maximal actuation speed of the actuators measured during this research is more than 350 mm/s. Positioning experiments with a laser interferometer and a PI controller showed that these actuators are able to achieve sub-micron positioning resolution

Patterns of Denial in Sex Offenders: A Replication Study

To assess whether a robust typology of sex offenders could be established based on the patterns of denial displayed, a previously developed semistructured interview method was used to assess denial in a mixed group of convicted rapists and child molesters. Cluster analysis was used to establish homogeneous groups of sex offenders based on the pattern of denial in each case, with a three-cluster solution emerging as the most appropriate, confirming previous research. The denial groups were compared in relation to objective offense characteristics to assess whether a consistent typology of offenders emerged. Each of the four groups of offenders identified (three groups emerging from the cluster analysis and an "absolute denier" group) corresponded closely with the previously identified typology. However, the authors failed to replicate previously identified differences between the denial groups in relation to independent variables such as offense type. Each group contained both rapists and child molesters and was found to differ quantitatively rather than qualitatively in the pattern of the denial expressed, with attributional style being the most consistent form of denial present in all groups. The authors conclude that denial consists of at least two continuous dimensions, rather than being a dichotomous phenomenon. Differences in the patterns of denial displayed by rapists and child molesters were found to be primarily quantitative rather than qualitative