X-Ray absorption study of CeO2 and Ce/V mixed oxide thin films obtained by sol-gel deposition

CeO₂ and Ce/V mixed oxide thin films prepared by sol-gel deposition and annealed in an air or argon atmosphere have been studied by chronocoulometry and by XAFS (X-ray absorption fine structure). Multielectron photoexcitations (MPE), well known to pervade XAFS spectra of Ce making the analysis of structural parameters unreliable, are removed with the help of the atomic absorption background, determined on simple Ce compounds. Distinct MPE estimates for Ce³⁺ and Ce⁴⁺ ions are used. In the analysis of the recovered pure XAFS signal, the degree of disorder is found to depend on the Ce/V molar ratio and on the heating atmosphere. The disorder correlates with charge capacity of films, both increasing with vanadium content and V⁴⁺/V⁵⁺ molar ratio.     

Interaction effects of energy efficiency policies: a review

Increasing energy efficiency and savings will play a key role in the achievement of the climate and energy targets in the European Union (EU). To meet the EU’s objectives for greenhouse gas emission reductions, renewable energy use and energy efficiency improvements, its member states have implemented and will design and implement various energy policies. This paper reviews a range of scientific articles on the topic of policy instruments for energy efficiency and savings and evaluates the strengths and weaknesses of different measures. The review demonstrates the variety of possible instruments and points to the complex policy environment, in which not a single instrument can meet the respective energy efficiency targets, but which requires a combination of multiple instruments. Therefore, the paper in particular focuses on assessing potential interactions between combinations of energy efficiency policies, i.e. the extent to which the different instruments counteract or support one another. So far, the literature on energy efficiency policy has paid only limited attention to the effect of interacting policies. This paper reviews and analyses interaction effects thus far identified with respect to factors that determine the interaction. Drawing on this review, we identify cases for interaction effects between energy efficiency policies to assess their potential existence systematically and to show future research needs.     

X-ray absorption in atomic potassium

A new high-temperature absorption cell for potassium vapor is described. X-ray absorption coefficient of atomic potassium is determined in the energy interval of 600 eV above the K edge where thresholds for simultaneous excitations of 1s and outer electrons, down to [1s2p] excitation, appear. The result represents also the atomic absorption background for XAFS (X-ray absorption fine structure) structure analysis. The K ionization energy in the potassium vapor is determined and compared with theoretical data and with the value for the metal.     

A videosharing social networking intervention for young adult cancer survivors

Clinicians interested in taking a proactive approach to healthy cancer survivorship might consider the use of a social networking and videosharing platform tailored specifically for young adult cancer survivors. This study examines six key factors that may influence a childhood cancer survivor’s participation in a social networking and videosharing intervention program tailored to their needs: (1) the individual’s social capital, defined as resources accessed by individuals through a broad range of social connections, (2) social support, (3) family interaction, (4) self-efficacy, (5) depression, and (6) self-reported quality of life. Fourteen healthy childhood cancer survivors participated in a social networking and videosharing intervention program, LIFECommunity, over a period of 6 months. Young adult cancer survivors with weak “bonding” social capital with other cancer survivors, little social support from friends and family, and lower family interaction participated in the social networking intervention more than those with stronger social capital and larger bases of support. The findings suggest that cancer survivors used the social network as a way to fulfill needs that were not being met in their “offline” lives. The study provides a deeper understanding of the factors that contribute to the success of social networking interventions for young cancer survivors.     

Structural and electrochemical investigations of Ce/Cu mixed oxide thin films

Thin films of Ce/Cu mixed oxide with molar ratios of 1 and 2 were prepared from inorganic precursors using the sol-gel route. Various electrochemical and spectroscopic techniques were used for characterization of the films and investigation of their optical and electrochemical properties. It was found that the redox behaviour significantly depends on the Ce/Cu ratio and on the concentration of Li⁺ ions. Slow kinetics of the charge transfer reactions was evident from cyclic voltammetry measurements of both types of films only at low scan rates (<20 mV/s). Measurement of X-ray absorption fine structure (XAFS) indicated that the local structure of Ce and Cu ions is not affected by the Ce/Cu molar ratio.     

Policy schemes,operational strategies and system integration of residential co-generation fuel cells

This study presents a holistic approach for the commercialisation of fuel cells for stationary applications. We focus our analyses on microCHP based on SOFC units fired with natural gas. We analyse the interaction of operational strategies under different ownership arrangements, required support levels and system integration aspects. The operational strategies, support mechanisms and ownership arrangements have been identified through actor analysis involving experts from Denmark, France and Portugal. With regard to operational strategies, the actor analyses led us to distinguishing between a heat-driven strategy, with and without time-differentiated tariffs, and an electricity price driven strategy for the operation as a virtual power plant. The corresponding support schemes identified cover feed-in tariffs, net metering and feed-in premiums. Additionally, the interplay of the microCHP units with the national energy systems has been analysed. Our main findings are that net metering would be an appropriate tool to support FC based microCHP in Denmark, whereas a price premium would be the preferable tool in France and Portugal.