Hydrogen sulfide (H 2 S) dissociation into hydrogen and sulfur has been studied in a pulsed corona discharge reactor (PCDR). Due to the high dielectric strength of pure H 2 S (~2.9 times higher than air), a non-thermal plasma could not be sustained in pure H 2 S at discharge voltages up to 30 kV with our reactor geometry. Therefore, H 2 S was diluted with another gas with lower dielectric strength to reduce the breakdown voltage. Breakdown voltages of H 2 S in four balance gases (Ar, He, N 2 and H 2) have been measured at different H 2 S concentrations and pressures. Breakdown voltages are proportional to the partial pressure of H 2 S and the balance gas. With increasing H 2 S concentrations, H 2 S conversion initially increases, reaches a maximum, and then decreases. H 2 S conversion and the reaction energy efficiency depend on the balance gas and H 2 S inlet concentrations. H 2 S conversion in atomic balance gases, such as Ar and He, is more efficient than that in diatomic balance gases, such as N 2 and H 2. These observations can be explained by proposed reaction mechanisms of H 2 S dissociation in different balance gases. The results show that nonthermal plasmas are effective for dissociating H 2 S into hydrogen and sulfur.

Black Hole Attacks are a serious threat to communication in tactical MANETs. In this work we present TOGBAD a new centralised approach, using topology graphs to identify nodes attempting to create a black hole. We use well-established techniques to gain knowledge about the network topology and use this knowledge to perform plausibility checks of the routing information propagated by the nodes in the network. We consider a node generating fake routing information as malicious. Therefore, we trigger an alarm if the plausibility check fails. Furthermore, we present promising first simulation results. With our new approach, it is possible to already detect the attempt to create a black hole before the actual impact occurs.

A novel pulsed corona wire-in-tube reactor with quartz view-ports allowed visual observation of the effect of charge voltage and gas composition on the corona distribution. The H 2 S conversion and energy efficiency of H 2 S decomposition in this pulsed corona discharge reactor varied at constant power due to the selected values of the electrical parameters of pulse forming capacitance, charge voltage, and pulse frequency. Low pulse forming capacitance, low charge voltage, and high pulse frequency operation produce the highest energy efficiency for H 2 S conversion at constant power. H 2 S conversion is more efficient in Ar-N 2 gas mixtures than in Ar or N 2. These results can be explained by corona discharge observations, the electron attachment reactions of H 2 S at the streamer energies, and a proposed reaction mechanism of H 2 S dissociation in the Ar-N 2 gas mixture. The energy consumption per molecule of converted H 2 S in an equimolar mixture of Ar and N 2 is the lowest that has been reported for any plasma reactor operated at non-vacuum pressures. The results reveal the potential for energy efficient H 2 S decomposition in pulsed corona discharge reactors.

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This work reports the effect of capacitance, cathode material, gas flow rate and specific energy input on methane conversion, energy efficiency and product selectivity in a co-axial cylinder pulsed corona discharge reactor. Ethane and acetylene appear to be formed from dimerization of CH 3 radicals and CH radicals, respectively, while ethylene is formed mainly from the dehydrogenation of ethane. At a given power input, low capacitance with high pulse frequency results in higher methane conversion and energy efficiency than operation at high capacitance with low pulse frequency. Platinum coated stainless steel cathodes slightly enhance methane conversion relative to stainless steel cathodes, perhaps due to a weak catalytic effect. As specific energy input increases, energy efficiency for methane conversion goes through a minimum, while the selectivity of acetylene has a maximum value. Comparison of methane conversion for different types of plasma reactors shows that the pulsed corona discharge is a potential alternative method for low temperature methane conversion.