The stand-off, range-resolved detection of hydrogen production rates is a valuable mechanism for the long-term condition monitoring of packages containing intermediate-level nuclear materials. To exploit this effect we have developed a long-range optical sensor system which uses Raman detection of hydrogen. Our need for operation over extended ranges (up to 100m) results in very low Raman signals. We therefore use time-correlated (with respect to the outgoing excitation laser pulse) and spectrally-resolved single-photon detection to ascertain molecular species, position and concentration as revealed by photon energy, arrival time and number, respectively.

Recently, the Bitcoin-underlying blockchain technology gained prominence as a solution that offers the realization of distributed trust-free systems, where economic transactions are guaranteed by the underlying blockchain. We are still at an early stage and thus require a deeper understanding of how the blockchain potentials can be realized, and what are the opportunities and challenges in so doing. Following a design science approach, we developed a proof of concept prototype that has the potential to replace a trust-based coffee shop payment solution that is based on an analogue, pre-paid punch card solution. The demonstrator provides a starting point to evaluate the strengths and weaknesses of the blockchain technology when replacing a trust-based by a trust-free transaction system. We conclude that the secure and trust-free blockchain-based transaction has the potential to change many existing trust-based transaction systems, but that scalability issues, costs, and volatility in the transaction currency are hindrances.

A novel trinuclear Al(III) citrate complex, [Al(H2O)6][(Al3(C6H4O7)2(OH)2(H2O)4]2(NO3)·6H2O, can be synthesised from solutions containing 1 ∶ 1 and 10 ∶ 1 aluminium to citrate ratios providing the pH is within the range 1.2–3.0.