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Abstract The question whether coexistence of marine renewable energy (MRE) projects and marine protected areas (MPAs) is a common spatial policy in Europe and how a number of factors can affect it, has been addressed by empirical research undertaken in eleven European marine areas. Policy drivers and objectives that are assumed to affect coexistence, such as the fulfillment of conservation objectives and the prioritization of other competing marine uses, were scored by experts and predictions were crosschecked with state practice. While in most areas MRE-MPA coexistence is not prohibited by law, practice indicates resistance towards it. Furthermore expert judgment demonstrated that a number of additional factors, such as the lack of suitable space for MRE projects and the uncertainty about the extent of damage by MRE to the MPA, might influence the intentions of the two major parties involved (i.e. the MRE developer and the MPA authority) to pursue or avoid coexistence. Based on these findings, the interactions of these two players are further interpreted, their policy implications are discussed, while the need towards efficient, fair and acceptable MRE-MPA coexistence is highlighted.

A full understanding of the elementary processes taking place in dye-sensitised solar cells requires an accurate description of the electronic structure of the dyes, the semiconductor surface, the electrolyte and their interactions. This review describes how electronic structure calculations have contributed to the field since its first steps and what methodologies have been adopted to study the charge transfer processes at the interface. Not all properties are equally predictable with electronic structure methods, and this work highlights the main success areas (e.g. the rationalization of the optical properties of the dyes), the recent developments (e.g. the improved description of the dye–semiconductor interaction) and the key challenges for the future (e.g. the calculation of charge recombination rate).

This paper illustrates a formulation of a continuous state space model in dq frame of the Thyristor Controlled Reactor (TCR), which can be used for stability studies by eigenvalue analysis. Differently from the previous approaches, this model is just addressed to reproduce the operation of the non-linear part of the TCR system, without considering shunted capacitor or control system, thus obtaining a characterization of the TCR independent from the application. A typical problem of the continuous models in dq frame of the TCR system is the presence of an un-damped homogenous current component in the solution, which is inconsistent with the real operation; the proposed model solves this problem improving the accuracy. The model performance has been also evaluated in the frequency domain comparing the obtained results with a numerical simulation of the TCR implemented by PSIM program.

The correlations between skeletal parameters (bulk density, micro-density and porosity), coral age and sea surface temperature were assessed along a latitudinal gradient in the zooxanthellate coral Balanophyllia europaea and in the azooxanthellate coral Leptopsammia pruvoti. In both coral species, the variation of bulk density was more influenced by the variation of porosity than of micro-density. With increasing polyp age, B. europaea formed denser and less porous skeletons while L. pruvoti showed the opposite trend, becoming less dense and more porous. B. europaea skeletons were generally less porous (more dense) than those of L. pruvoti, probably as a consequence of the different habitats colonized by the two species. Increasing temperature had a negative impact on the zooxanthellate species, leading to an increase of porosity. In contrast, micro-density increased with temperature in the azooxanthellate species. It is hypothesized that the increase in porosity with increasing temperatures observed in B. europaea could depend on an attenuation of calcification due to an inhibition of the photosynthetic process at elevated temperatures, while the azooxanthellate species appears more resistant to variations of temperature, highlighting possible differences in the sensitivity/tolerance of these two coral species to temperature changes in face of global climate change.

We report the properties of a shape-persistent tetra-terpyridine ligand whose coordination to transition metal ions guides its three-dimensional self-assembly in two steps: at first, nanoscale objects form, which with time, self-assemble into micrometer structures. This work highlights the potential for control of the molecular self-assembly of molecules on the nanoscale, and the successive self-assembly of the formed supramolecular nanosystems to yield mesoscopic objects.

A numerical study of heat transfer to supercritical water in vertical tubes is carried out using the ANSYS-CFX code and employing the k-omega SST turbulence model. The numerical results on wall tem ...

The Indian Ocean Experiment (INDOEX) was an international, multiplatform field campaign to measure long-range transport of air pollution from South and Southeast Asia toward the Indian Ocean during the dry monsoon season in January to March 1999. Surprisingly high pollution levels were observed over the entire northern Indian Ocean toward the Intertropical Convergence Zone at about 6°S. We show that agricultural burning and especially biofuel use enhance carbon monoxide concentrations. Fossil fuel combustion and biomass burning cause a high aerosol loading. The growing pollution in this region gives rise to extensive air quality degradation with local, regional, and global implications, including a reduction of the oxidizing power of the atmosphere.

Plants and cyanobacteria use the chlorophylls embedded in their photosystems to absorb photons and perform charge separation, the first step of converting solar energy to chemical energy. While oxygenic photosynthesis is primarily based on chlorophyll a photochemistry, which is powered by red light, a few cyanobacterial species can harness less energetic photons when growing in far-red light. Acclimatization to far-red light involves the incorporation of a small number of molecules of red-shifted chlorophyll f in the photosystems, whereas the most abundant pigment remains chlorophyll a. Due to its different energetics, chlorophyll f is expected to alter the excited-state dynamics of the photosynthetic units and, ultimately, their performances. Here we combined time-resolved fluorescence measurements on intact cells and isolated complexes to show that chlorophyll f insertion slows down the overall energy trapping in both photosystems. While this marginally affects the efficiency of photosystem I, it substantially decreases that of photosystem II. Nevertheless, we show that despite the lower energy output, the insertion of red-shifted chlorophylls in the photosystems remains advantageous in environments that are enriched in far-red light and therefore represents a viable strategy for extending the photosynthetically active spectrum in other organisms, including plants. However, careful design of the new photosynthetic units will be required to preserve their efficiency.