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Climate-controlled changes in eustatic sea level (ESL) are linked to transfers of water between ocean and land, thus offering a rare insight into the past hydrological cycle. In this study, we examine the timing and phase of Milankovitch-scale ESL cycles in the peak Cretaceous greenhouse, the early Turonian (-93-94 million years, Myr, ago). A high-resolution astronomical framework established for the Bohemian Cretaceous Basin (central Europe) suggests a -400-kyr pace and a distinct asymmetry of interpreted ESL cycles. The rising limbs of ESL change constitute only 20-30 % of the cycle, and are encased entirely within the falling phase of the 405-kyr eccentricity. The intervening ESL falls (<= 6 m in magnitude) are more protracted, starting within 70 kyr prior to the eccentricity minima and culminating -60 kyr after the 405-kyr eccentricity maxima. Despite similarities to the sawtooth shape of -100-kyr glacioeustatic oscillations of the Late Pleistocene, the time scales and phasing are unparalleled in the Pleistocene icehouse. A similar, 405-kyr pace is found in ice-volume variations of the early Miocene, but the timing of glacioeustatic change relative to eccentricity forcing is incompatible with the phase of greenhouse sea-level oscillations. The phasing points to major differences in the geographic location and insolation sensitivity of the key hydrological reservoirs under icehouse and greenhouse regimes. The inferred structure of greenhouse eustasy points to low- or middle-latitude water storage, likely aquifers, that charge (expand) with rising seasonality variations and discharge (contract) with declining seasonality amplitudes on the 405-kyr scale. The net volume of water transferred on these time scales is within 2.2 x 106 km3, equivalent to <= 10 % of the present-day storage in the uppermost 2 km of continental crust. Potential additive interference with steric eustasy, proportionally relevant during greenhouse regimes, could reduce the volumes required for continental storage.

Hydrogen generation from water using solar energy has grown into a promising approach for sustainable energy production. Over the last years, graphitic carbon nitrides (g-C3N4, CN), polymers based on the heptazine-group, have been widely applied as photocatalysts for H2 evolution. The poor charge separation efficiency of CN is considered the major drawback. Here, we investigated the effect of coupling CN with different types of carbon nanotubes on the charge transfer properties and the photocatalytic H2 evolution. We used carbon nanotubes (CNTs) of different wall number (single (SWCNTs), double (DWCNTs) and multi-walled (MWCNTs) CNTs) for the development of full-organic CN based composite photocatalysts. Photoactivity was drastically affected by the content but more importantly by the nature of the CNTs. The SWCNTs functionalized CN composites were the most active presenting approximately 2-5 times higher H2 evolution than the corresponding DWCNTs and MWCNTs functionalized CN under both solar and pure visible light irradiation. Photoactivity was primarily controlled by the improved electronic properties linked with the abundance and stability of photogenerated charges as evidenced by electron paramagnetic resonance spectroscopy. Transient absorption spectroscopy verified the transfer of reactive electrons from CN to CNTs. CNTs functioned as electron acceptors improving charge separation. The data suggest that charge transfer is inversely proportional to the wall number of the CNTs and that photoactivity is directly controlled by the size at the nanoscale of the CNTs used. In the CNTs/CN nanocomposites, photogenerated electrons are transferred more efficiently from CN when SWCNTs are used, providing more available electrons for H2 production.

Ostrava in the Moravian-Silesian region (Czech Republic) is a European air pollution hot spot for airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and ultrafine particles (UFPs). Air pollution source apportionment is essential for implementation of successful abatement strategies. UFPs or nanoparticles of diameter <100 nm exhibit the highest deposition efficiency in human lungs. To permit apportionment of PM sources at the hot-spot including nanoparticles, Positive Matrix Factorization (PMF) was applied to highly time resolved particle number size distributions (NSD, 14 nm-10 μm) and PM0.09-1.15 chemical composition. Diurnal patterns, meteorological variables, gaseous pollutants, organic markers, and associations between the NSD factors and chemical composition factors were used to identify the pollution sources. The PMF on the NSD reveals two factors in the ultrafine size range: industrial UFPs (28%, number mode diameter - NMD 45 nm), industrial/fresh road traffic nanoparticles (26%, NMD 26 nm); three factors in the accumulation size range: urban background (24%, NMD 93 nm), coal burning (14%, volume mode diameter - VMD 0.5 μm), regional pollution (3%, VMD 0.8 μm) and one factor in the coarse size range: industrial coarse particles/road dust (2%, VMD 5 μm). The PMF analysis of PM0.09-1.15 revealed four factors: SIA/CC/BB (52%), road dust (18%), sinter/steel (16%), iron production (16%). The factors in the ultrafine size range resolved with NSD have a positive correlation with sinter/steel production and iron production factors resolved with chemical composition. Coal combustion factor resolved with NSD has moderate correlation with SIA/CC/BB factor. The organic markers homohopanes correlate with coal combustion and the levoglucosan correlates with urban background. The PMF applications to NSD and chemical composition datasets are complementary. PAHs in PM1 were found to be associated with coal combustion factor.

This paper presents a mechanism for developing knowledge based support for real time application of multiagent systems (MAS) in control, automation and diagnosis of electric power systems. In particular it presents a way for autonomous agents to utilize a qualitative means-ends based model for reasoning about control situations. The proposed mechanism has been used in different scenarios of electric power distribution system protection and control. Results show that agents can use local models of their environment and coordinate with other agents to analyze and understand a disturbance situation and choose an appropriate control action. The paper also elaborates on real time interfacing between multi-agent systems and industry standard distribution automation and control system.

The paper presents a method of analysis and design of urban landscapes called PlaceMaker. The method is intended as a key resource for assessing the identity of places and measures for its enhancement, reconstruction and design. By using different tools for analysis and interpretation of places and questionnaires administered to their users, PlaceMaker finds the identity material that the city has available and how to de-compose and re-compose it for its sustainable project transformation. Pedestrian-intensive areas, in particular urban, cultural and historical poles of attraction, increasingly bear the imprint of globalization, conveying messages which have developed in an uncontrolled manner and are aimed at conveying their users' patterns of thought and action. The presence of a dense mixture of contrasting elements and perceptions can detract from the image of a city. As regards, the paper is completed with a synopsis of the experiment carried out in an historic axe in London - Oxford Street - where globalization is in danger of levelling out the beauty of the area in favour of widespread genericity

Great efforts have been paid to improve engine efficiency as well as to reduce the pollutant emissions. The direct injection allows to improve the engine efficiency; on the other hand, the GDI combustion produces larger particle emissions. The properties of fuels play an important role both on engine performance and pollutant emissions. In particular, great attention was paid to the octane number. Oxygenated compounds allow increasing gasoline's octane number and play an important role in PM emission reduction. In this study was analyzed the effect of fuels with different RON and with ethanol and ethers content. The analysis was performed on a small GDI engine. Two operating conditions, representative of the typical EUDC cycle, were investigated. Both the engine performance and the exhaust emissions were evaluated. The gaseous emissions and particle concentration were measured at the exhaust by means of conventional instruments. Particle size distribution function was measured in the range from 5.6 nm to 560 nm by means of an Engine Exhaust Particle Sizer (EEPS). The results point out that the better result in terms of performance and emission reduction was observed for the high RON fuel. The fuels with ethanol as additive show a large fuel consumption and a not valuable effect on exhaust emissions

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).

AbstractProjections show that biomass will remain important for reaching future EU renewable energy targets. In addition to using domestic biomass, European bioenergy markets will also partly rely on imports of biomass, in particular in trade‐oriented EU member states like the United Kingdom, the Netherlands, Belgium, and Denmark. There has been a lot of debate on the sustainability of (imported) biomass and how policy should deal with this. In this research, therefore, we defined long‐term strategies for sustainable biomass imports in European bioenergy markets. We used the input of different stakeholders in our approach through focus‐group discussions and a global survey, focusing on the following aspects: key principles of sustainable biomass trade, risks and opportunities of biomass trade, both for import regions (EU countries) and for sourcing regions, and practical barriers for trade. Overall we conclude that policies should be stable and consistent within a long‐term vision. An overall sustainability assurance framework of biomass production and use is key, but should ultimately apply to all end uses of biomass. Furthermore, the mobilization of biomass should be supported, as well as commoditization, considering the large diversity of biomass. Side impacts of biomass use should be monitored. Reducing investors’ risk perception is crucial for future developments in the biobased economy, and a clear policy to phase out fossil fuels, e.g. through a carbon tax, needs to be implemented. The results of this research are of interest for policy makers when deciding on long‐term strategies concerning sustainable bioenergy markets. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd