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Abstract: Simple bio-molecules demonstrate a propensity to form hydrogen-bonded networks. Here, individual hydrogen-bond energies are determined through topological analysis of the theoretical electron density for a variety of systems, demonstrating the existence of a universal relationship between hydrogen-bond length and strength. Comparison of local hydrogen-bond strength to global stabilisation allows the quantification of contributions to intermolecular interactions within surface overlayers in unprecedented detail. [Copyright &y& Elsevier]

Abstract: We demonstrate charge pumping in semiconducting carbon nanotubes by a traveling potential wave. From the observation of pumping in the nanotube insulating state we deduce that transport occurs by packets of charge being carried along by the wave. By tuning the potential of a side gate, transport of either electron or hole packets can be realized. Prospects for realization of nanotube-based single electron pumps are discussed. [Copyright &y& Elsevier]

A radiation hard, compact, ion chamber detector system is described. The chambers are planar, with narrow gaps, and are filled with nitrogen gas. They operated at a signal rate equivalent to ∼2×108 minimum ionizing tracks per cm2, delivered in pulses 250 ns long, while monitoring an intense scattered electron flux. [Copyright &y& Elsevier]

The (π+,pd), and (π+,dd) reactions on 6Li and 12C targets were investigated with pions of 100 and 165 MeV kinetic energy. The experimental apparatus employed for this work is characterized by good energy resolution (<3%, ΔE/E) and angle definition (Δθ=1.6°), and the measurements span a large fraction of the final-state particle phase space. Results are compared to extensive Monte Carlo simulations in order to investigate the role of single-step and multistep absorption processes in these nuclei. In comparison with previously published (π+,pp) data on the same targets and at the same beam energies, specific kinematic regions were identified in which the neutron hard pickup process n+p→d dominated the observed deuteron yield. The contribution of direct quasitriton absorption is significant only at 100 MeV. [Copyright &y& Elsevier]