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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

Supervisory Control and Data Acquisition (SCADA) systems monitor and control electric power distribution. Recent history has shown that cyber-attacks pose a tremendous risk for the economy and safety of modern countries. This paper introduces an architecture and a prototype implementation for a process-aware, network-based Intrusion Detection System (IDS) to secure control networks in the domain of power distribution. Based on a recently proposed process model, the system continuously assesses the local physical process and all control commands with regard to consistency and safety of the underlying physical process. Its detection capabilities focus on process-based attacks like manipulated control commands, which appear legitimate to traditional IDS but might nevertheless have devastating effects on the power distribution. The architecture separates the evaluation part from the traffic processing, which ensures extensibility and scalability. The developed implementation has been successfully deployed at a Dutch power distribution substation. Its detection performance is characterized by a very low miss rate and high precision.

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).

In the present paper design, realization and testing of a novel small scale adsorption refrigerator prototype based on activated carbon/ethanol working pair is described. Firstly, experimental activity has been carried out for identification of the best performing activated carbon available on the market, through the evaluation of the achievable thermodynamic performance both under air conditioning and refrigeration conditions. Once identified the best performing activated carbon, the design of the adsorber was developed by experimental dynamic performance analysis, carried out by means of the Gravimetric-Large Temperature Jump (G-LTJ) apparatus available at CNR ITAE lab. Finally, the whole 0.5 kW refrigerator prototype was designed and built. First experimental results both under reference air conditioning and refrigeration cycles have been reported, to check the achievable performance. High Specific Cooling Powers (SCPs), 95 W/kg and 50 W/kg, for air conditioning and refrigeration respectively, were obtained, while the COP ranged between 0.09 and 0.11, thus showing an improvement of the current state of the art.

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

Latent thermal energy storage systems represent a promising alternative to traditional sensible storages, but their exploitation requires a careful design of the system. The present paper reports a mathematical model for the simulation of thermal energy storage systems with phase change materials (PCMs). The model is suitable for the description of a latent heat storage using a fin-and-tube heat exchanger. Accuracy and computational effort are both taken into consideration, by coupling a 1D model for the tubes of the heat exchanger and a reduced 3D model for the material and fin domains. The developed model has been validated for two systems, realised at ITAE and ISE, differing for the PCM employed and the constructive characteristics of the heat exchanger. Results show that the model has a good accuracy and could predict the behaviour of the storages within 40 W error in case of powers and 1 K in case of heat transfer fluid temperatures. When a stable PCM was used, the average deviation between the PCM temperature in experiments and simulation was lower than 0.6 K.

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.

Species distribution models (SDMs) provide realistic scenarios to explain the influence of bioclimatic variables on plant pathogen distribution. Diplodia sapinea is most harmful to plantations of both exotic and native pine species in Italy, causing economic consequences expecially to edible seed production. In this study, we developed maximum entropy models for D. sapinea in Italy to reach the following goals: (i) to carry out the pathogen's first geographical distribution analysis in Italy and determine which ecogeographical variables (EGVs) may influence its outbreaks; (ii) to detect the effect of climate change on the potential occurrence of disease outbreaks by 2050 and 2070. We used Maxent ver. 3.4.0 to develop SDMs. We used six global climate models (BCC-CSM1-1, CCSM4, GISS-E2-R, MIROC5, HadGEM2-ES and MPI-ESM-LR) for two representative concentration pathways (4.5 and 8.5) and two time projections (2050 and 2070) to detect future climate projections of D. sapinea. The most important EGVs influencing outbreaks were land cover, altitude, mean temperature of driest and wettest quarter, precipitation of wettest quarter, precipitation seasonality and minimum temperature of coldest month. The distribution of D. sapinea mostly expanded in central and southern Italy and shifted in altitude upwards on average by ca. 93m a.s.l. Moreover the fungus expanded the range where disease outbreaks may be recorded in response to an increase in the mean temperature of wettest and driest quarter by ca. 1.9 C and 5.8 C, respectively in all climate change scenarios. Precipitation of wettest quarter did not differ between current and any of future models. Under different climate change scenarios D. sapinea's disease outbreaks will be likely to affect larger areas of pine forests in the country, probably causing heavy effects on the dynamics and evolution of these stands or perhaps constraining their survival.