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Abstract The paper presents a life cycle assessment of a kenaf-fibre insulation board following the international standards of the ISO 14040 series. Each life-cycle step has been checked, from kenaf production and board manufacture by an Italian firm, to use and disposal. The aim is to assess the board eco-profile and to compare, on the basis of a life-cycle approach, the energy and environmental benefits and drawbacks related to its employment into a typical residential dwelling. A comparison among various insulating materials has been carried out. The study focuses also on processes and input materials which cause the main environmental impacts of the product, and points out critical issues and the life-cycle steps with the highest improvement potentials.

Grape production is highly responsive to weather conditions and therefore very sensitive to climate change. To evaluate how viticulture in the traditional Italian wine region Emilia-Romagna could be affected by climate change, several bioclimatic indices describing the suitability for grapevine production were calculated for two future periods (2011–2040 and 2071–2100) using CORDEX (Coordinated Regional Climate Downscaling Experiment) high-resolution climate simulations under two Representative Concentration Pathways (RCP) scenarios—RCP 4.5 and RCP 8.5. The projections for both of the RCP scenarios showed that most of the Emilia-Romagna region will remain suitable for grape production during the period 2011–2040. By the end of the twenty-first century, the suitability to produce grapes in Emilia-Romagna could be threatened to a greater or smaller extent, depending on the scenario. During the period 2071–2100, the entire Emilia-Romagna region will be too hot for grape production under the RCP 8.5 scenario. Under the RCP 4.5 scenario, changes will be milder, suggesting that the Emilia-Romagna region could still be suitable for grape cultivation by the end of the twenty-first century but would likely require certain adjustments.

Decomposition of five amino acids, alanine, serine, cysteine, aspartic acid, and asparagine, under irradiation with soft X rays (magnesium Kalpha X-ray source) in ultra-high vacuum was studied by means of X-ray photoelectron spectrometry (XPS) and mass spectrometry. A comparative analysis of changes in XPS line shapes, stoichiometry and residual gas composition indicates that the molecules decompose by several pathways. Dehydration, decarboxylation, decarbonylation, deamination and desulfurization of pristine molecules accompanied by desorption of H2, H2O, CO2, NH3 and H2S are observed with rates depending on the specific amino acid. NEXAFS spectra of cysteine at the carbon, oxygen and nitrogen K-shell and sulfur L2,3 edges complement the XPS and mass spectrometry data and show that the exposure of the sample to an intense soft X-ray synchrotron beam results in the formation of C-C and C-N double and triple bonds. Qualitatively, the amino acids studied can be arranged in the following ascending order of radiation stability: serine

The scaling of thin film photovoltaics to a commercially viable size relies on the series connection of multiple small cells into modules. These interconnections are typically formed by three patterning steps, each of which have an impact on the series resistance and consequently on the total module performance. Here, we implement the transmission line method for the complete analysis of the P2 patterning step of the photoactive layer in organic photovoltaic modules. Devices are investigated with a sample design that allows for a comparative study of the P2 connection on the solar cell performance. We compare subtractive mechanical scribing to a newly developed additive pre-patterning method for the P2 step. Aerosol Jet printed pre-patterning lines of low surface energy and conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) modified with a fluorosurfactant repel the subsequently spray coated photoactive layer. Furthermore, the influence of MoO3 in the P2 pattern is elucidated, displaying a substantial increase in series resistance and decrease in device performance.

Abstract With the rapidly increasing capacity of renewable energy production, the volatile nature of, e.g., wind and solar power necessitates solutions for storing excess energy. A finite-element model for simulating a geomembrane energy storage system is developed, in order to aid the development of the system and provide first insights into the performance of the system. Conceptually, energy is stored by pumping water from a nearby surface reservoir into a subsurface reservoir confined by a geomembrane, which lifts the overlying mass of soil, thereby increasing the potential energy due to gravity. An axisymmetric finite-element model is developed employing fluid cavity elements and fluid exchange links to simulate inflow and outflow of the reservoir, which resembles energy storage and energy re-harvest, respectively. A sophisticated constitutive model for a granular soil is employed using a hypoplastic model with intergranular strain extension, which includes essential characteristics as stress and density dependency, critical-state behavior as well as stress reversals. Analysis of repeated storage cycles provides realistic but undesirable deformation patterns, encountered by increasing irreversible displacements with advancing cycles. The reliable results of the model directly provides estimates of energy efficiency and can serve as a tool for further development and optimization of the energy storage system.

This paper deals with an investigation on the combustion process and pollutant formation of a small diesel engine fuelled with blended and pure biodiesel. The engine is a three-cylinder, 1028 cc, equipped with a common rail injection system. Endoscope based optical setup was used to observe in the cylinder without significant interference to the combustion process. Combustion images were post-processed by two-colour pyrometry method to evaluate the flame temperature and the in-cylinder soot concentration. Optical data were correlated to the nitrogen oxides and the particulate matter emissions measured at exhaust. Experiments were carried out at different operating conditions. It was found out that without EGR (exhaust gas recirculation), blended and pure RME (rapeseed methyl ester) were characterized by higher flame temperature and also by higher NOx emissions. In presence of EGR, lower flame temperature was detected for biodiesel; in this case higher NOx emissions were measured with biodiesel but the difference with NOx emissions from diesel fuel were reduced. Moreover, blended and pure biodiesel combustion was characterized by lower in-cylinder soot formation and also lower PM (particulate matters) at exhaust

Abstract Reconnection events in high current reversed field pinch plasmas are often associated to the partial or total loss of the helical magnetic topology. The electron temperature collapse during these phenomena is investigated in RFX-mod thanks to high time resolution soft-x-ray diagnostics; these data are used, together with magnetic energy reconstructions, for energy balance analysis. The paper shows that the energy released during reconnection events, similarly to astrophysical plasmas, might be involved in ion heating, the latter being estimated by the energy distribution function of neutral atoms, a rather interesting feature in a reactorial perspective. These issues will be further investigated in RFX-mod2 , an upgrade of the present device starting its operations from 2022, where the modified boundary conditions are expected to increase the helical states duration and reduce the frequency of reconnection events.

Combined floating offshore wind turbines (FOWTs), wave energy converters (WECs), and floating solar photovoltaics (FPVs) systems have the potential to provide cost-effective solutions for offshore multi -energy complementation and structure protection. In this study, a theoretical model based on the potential flow theory and eigenfunction matching method is utilized to study wave diffraction and radiation by a co -located system, in which the main components of the wind platform and WECs are made of vertical cylindrical floats. Based on the displacement constraint matrix, coupled equations of motion are developed to calculate the kinematic response of the co -located systems. After running the convergence analysis and model validation, the present model is employed to perform a multiparameter impact analysis. Case studies are presented to clarify the effects of the WEC radius, draft, layout, power take -off (PTO) system, and incident wave heading and frequency on the hydrodynamic coefficient, wave energy capture width, and motion response of the wind platform. Our findings highlight that several factors play a crucial role in the performance of the co -located system, more importantly, that the theoretical model developed in this study is capable of effectively predicting the wave -structure interactions in wave fields, making it applicable to future wave farm projects.