Time-resolved single-particle x-ray scattering reveals electron-density as coherent plasmonic-nanoparticle-oscillation source

Dynamics of optically-excited plasmonic nanoparticles are presently understood as a series of sequential scattering events, involving thermalization processes after pulsed optical excitation. One important step is the initiation of nanoparticle breathing oscillations. According to established experiments and models, these are caused by the statistical heat transfer from thermalized electrons to the lattice. An additional contribution by hot electron pressure has to be included to account for phase mismatches that arise from the lack of experimental data on the breathing onset. We used optical transient-absorption spectroscopy and time-resolved single-particle x-ray-diffractive imaging to access the excited electron system and lattice. The time-resolved single-particle imaging data provided structural information directly on the onset of the breathing oscillation and confirmed the need for an additional excitation mechanism to thermal expansion, while the observed phase-dependence of the combined structural and optical data contrasted previous studies. Therefore, we developed a new model that reproduces all our experimental observations without using fit parameters. We identified optically-induced electron density gradients as the main driving source.Comment: 32 pages, 5 figures, 1 supporting information document include

Effect of Solution Composition on the Energy Production by Capacitive Mixing in Membrane-Electrode Assembly

The final edited version of the paper can be found at: http://pubs.acs.org/articlesonrequest/AOR-c9UMxSzGY3eiU5SENNgT The complete citation is: Ahualli, S.; et al. Effect of Solution Composition on the Energy Production by Capacitive Mixing in Membrane-Electrode Assembly. Journal of Physical Chemistry, 118(29): 15590-15599 (2014). DOI:10.1021/jp504461mOpen access in the Journal on May 26, 2015In this work we consider the extent to which the presence of multi-valent ions in solution modifies the equilibrium and dynamics of the energy production in a capacitive cell built with ion-exchange membranes in contact with high surface area electrodes. The cell potential in open circuit (OCV) is controlled by the difference between both membrane potentials, simulated as constant volume charge regions. A theoretical model is elaborated for steady state OCV, first in the case of monovalent solutions, as a reference. This is compared to the results in multi-ionic systems, containing divalent cations in concentrations similar to those in real sea water. It is found that the OCV is reduced by about 25 % (as compared to the results in pure NaCl solutions) due to the presence of the divalent ions, even in low concentrations. Interestingly, this can be related to the “uphill” transport of such ions against their concentration gradients. On the contrary, their effect on the dynamics of the cell potential is negligible in the case of highly charged membranes. The comparison between model predictions and experimental results shows a very satisfactory agreement, and gives clues for the practical application of these recently introduced energy production methods.The research leading to these results received funding from the European Union 7th Framework Programme (FP7/2007-2013) under agreement No. 256868. Further financial support from Junta de Andalucia, Spain (PE2012-FQM 694) is also acknowledged. One of us, M.M.F., received financial support throughan FPU grant from the Universityof Granada

Climate change and increased risk for the insurance sector: A global perspective and an assessment for the Netherlands.

Climate change is projected to increase the frequency and severity of extreme weather events. As a consequence, economic losses caused by natural catastrophes could increase significantly. This will have considerable consequences for the insurance sector. On the one hand, increased risk from weather extremes requires assessing expected changes in damage and including adequate climate change projections in risk management. On the other hand, climate change can also bring new business opportunities for insurers. This paper gives an overview of the consequences of climate change for the insurance sector and discusses several strategies to cope with and adapt to increased risks. The particular focus is on the Dutch insurance sector, as the Netherlands is extremely vulnerable to climate change, especially with regard to extreme precipitation and flooding. Current risk sharing arrangements for weather risks are examined while potential new business opportunities, adaptation strategies, and public-private partnerships are identified. © The Author(s) 2009

Climate Change and the Insurance Sector

Climate change matters to the insurance sector. In terms of underwriting, on one scenario, the economic cost of weather losses could reach over 1 trillion USD in a single year by 2040. The impacts will be worse in developing countries. The private sector needs to work with the public sector, as part of a “triple dividend” approach that coordinates adaptation, disaster management and sustainable economic development. For asset management the indirect impacts are key. Greenhouse gas emissions have to drop by 60 per cent by 2050, which means transforming the energy economy. Finance for renewables will reach 100 billion USD a year soon. Political uncertainty is a serious blockage to market forces, and the re-evaluation of assets and project returns is happening too slowly. Finally, insurers have a duty as ubiquitous players in the economy and society to help to shape climate policies in a responsible and effective way. The Geneva Papers (2008) 33, 71–90. doi:10.1057/palgrave.gpp.2510152

Bridging the gap between science and the stakeholder: The case of climate change research

This paper provides an overview of the EU-funded project ‘Modelling the Impact of Climate Extremes’ (MICE) and, specifically, the stakeholder collaboration and dissemination activities undertaken during the 3 year project. MICE was a pan-European end-to-end assessment of the potential impacts of climate change on a range of economic sectors important to the region. MICE actively encouraged the promotion of dialogue between the research and stakeholder communities in order to ensure that the research activities undertaken within the project were useful to the wider user community. Five workshops were held during the final 18 months of the project. In addition to these, a workshop report and a non-technical stakeholder-focussed brochure were produced to ensure that results do not remain solely within the academic community. The present paper provides a brief overview of the aims and objectives of the MICE project and describes the 5 workshops, including the rationale behind the structure of the final pan-European workshop, and selected results produced by the MICE Consortium. The main outcomes of the final workshop were (1) that the next 10 to 20 yr are important to stakeholders, whilst projections for the 2080s have limited relevance for decision-makers (2) the reliability of climate models needs to be increased and uncertainties decreased; (3) scientific results should be made accessible to the non-specialist, and stakeholders should be involved in relevant projects, preferably from the design stage; (4) there is the need to recognise and work to bridge the gap between what scientists can realistically achieve and what stakeholders require