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European physical journal special topics 228(2), 261-623 (2019). doi:10.1140/epjst/e2019-900045-4 Published by Springer, Berlin ; Heidelberg

Achieving a pinhole-free CdS layer is necessary to produce high performance thin film CdTe solar cells. Pinholes in the CdS layer can compromise the efficiency of a CdTe solar cell by causing shunts. We have investigated the use of a plasma treatment of a fluorine doped tin oxide coated glass substrate (NSG TEC 15) and its effect on pinhole reduction in thin film CdS layers grown by Chemical Bath Deposition. CdS films, <100 nm thickness, were deposited on both O2/Ar plasma cleaned and conventionally cleaned substrates. We show that the O2/Ar plasma treatment of the TEC 15 substrate reduced the water contact angle from ∼55° to less than 12° indicating a substantial increase in the surface energy. The CdS deposited on the plasma treated TEC 15 was pinhole free, very smooth and homogenous in morphology and composition. Scanning electron microscopy images show that the O2/Ar plasma treatment is effective in increasing film density and grain size. Corresponding spectroscopic ellipsometry measurements show an increase in the refractive index from 2.18 to 2.43 at 550 nm wavelength.

Climate change is currently attracting interest at both research and policy levels. However, it is usually explored in terms of its effect on agriculture, water, industry, energy, transport and health and as yet has been insufficiently addressed as a factor threatening cultural heritage. Among the climate parameters critical to heritage conservation and expected to change in the future, precipitation plays an important role in surface recession of stone. The Lipfert function has been taken under consideration to quantify the annual surface recession of carbonate stone, due to the effects of clean rain, acid rain and dry deposition of pollutants. The present paper provides Europe-wide maps showing quantitative predictions of surface recession on carbonate stones for the 21st century, combining a modified Lipfert function with output from the Hadley global climate model. Chemical dissolution of carbonate stones, via the karst effect, will increase with future CO(2) concentrations, and will come to dominate over sulfur deposition and acid rain effects on monuments and buildings in both urban and rural areas. During the present century the rainfall contribution to surface recession is likely to have a small effect, while the increase in atmospheric CO(2) concentration is shown to be the main factor in increasing weathering via the karst effect.

In Europe, regions in the Mediterranean area share common characteristics in terms of high sensitivity to climate change impacts. Does this translate into specificities regarding climate action that could arise from these Mediterranean characteristics? This paper sheds light on regional and local climate mitigation actions of the Mediterranean Europe, focusing on the plans to reduce greenhouse gases emissions in a representative sample of 51 regions and 73 cities across 9 Mediterranean countries (Croatia, Cyprus, France, Greece, Italy, Malta, Portugal, Slovenia, Spain). The study investigates: (i) the availability of local and regional mitigation plans, (ii) their goals in term of greenhouse gas emissions reduction targets on the short and medium-long term, and (iii) the impact of transnational climate networks on such local and regional climate mitigation planning. Results of this study indicate an uneven and fragmented planning, that shows a Mediterranean West-East divide, and a link with population size. However, overall, both regional and city action seem insufficiently ambitious with regards to meeting the Paris Agreement, at least at city level. While national frameworks are currently weak in influencing regional and local actions, transnational networks seem to be engaging factors for commitment (at city level) and ambitiousness (at regional level). The uneven and fragmented progress revealed by this study, does not align with the characteristics shared by investigated regions and cities in terms of environmental, socio-political, climatic and economic conditions. The results support the call of a common green deal at the Mediterranean level to further address specific Mediterranean challenges and related needs. This will allow to capitalise on available resources, generate local-specific knowledge, build capacities, and support Mediterranean regions and cities in preparing the next generation of more ambitious mitigation plans.

The present work proposes a differential scanning calorimetric (DSC) analysis approach in order to characterize a W/O emulsion in function of the vaporization temperature of the inner water droplets. The correlation between the most probable boiling temperatures of the droplets and their radii involves the evaluation of the story of the released energy during the vaporization process. The experimental setup consists in a heat flow DSC system provided by a temperature programmable oven. A set of seven emulsions, containing the same amount of water, is classified in function of the dispersed water droplet diameters and tested several times. The resulting thermograms are statistically processed to obtain the most probable vaporization temperature for every emulsion in function of the dispersed water droplets size. The results show that the smaller the dispersed water droplet, the higher the vaporization temperature. Moreover, a notable degree of metastability, included in a range temperature from 5 to 10 C, is pointed out and it is evident that it increases in reducing the dispersed water droplets size.