Search results for "72"
showing 10 items of 1431 documents
FIELD TESTING OF THE SMBF FLUME
2007
At first, in this paper the stage-discharge relationship of a new flume, originally proposed by Samani and Magallanez, for measuring flow discharge in open channels is reviewed. The flume is obtained inserting two semicylinders in a rectangular cross-section. Then, the results of some experimental runs carried out using horizontal flumes characterized by different values of the contraction ratio (ranging from 0.17 to 0.81) are used for determining the two coefficients of the power stage-discharge equation. Finally, the stage-discharge equation is tested using flow measurements carried out, in the period December 2004 – March 2006 in the Sicilian experimental SPA1 and SPA2 basins. Field test…
Optimization of photovoltaic energy production through an efficient switching matrix
2013
This work presents a preliminary study on the implementation of a new system for power output maximization of photovoltaic generators under non-homogeneous conditions. The study evaluates the performance of an efficient switching matrix and the relevant automatic reconfiguration control algorithms. The switching matrix is installed between the PV generator and the inverter, allowing a large number of possible module configurations. PV generator, switching matrix and the intelligent controller have been simulated in Simulink. The proposed reconfiguration system improved the energy extracted by the PV generator under non-uniform solar irradiation conditions. Short calculation times of the pro…
Sicilian potential biogas production
2013
This study is aimed at predicting the Sicilian potential biogas production, using the Organic Fraction of Municipal Solid Waste (OFMSW), animal manure and food industry by-products, in a region where only one biogas plant using MSW and one co-digestion plant are nowadays available. The statistical data about OFMSW, the number of animals bred in medium and large farms and the amounts of by-products of food processing industries were evaluated, in order to compute the Sicilian potential biogas and energy production. The OFMSW produced in Sicily, that is 0.8 million tons ca. per year (37% of MSW), could be used in a bio-reactor, together with other raw materials, for Anaerobic Digestion (AD) p…
Clean and Sustainable Biodiesel Production
2015
To date, the majority of world's primary energy is derived from fossil fuels. However, the fossil fuel recourses are in an inevitable decline as energy demand continues to grow exponentially with population growth, urbanization, and improved standards of living. Crude oil prices have recently risen several times and their current annual volatility exceeds 30%. The potential scarcity of fossil fuels has prompted a global search for alternative energy resources. Biodiesel fulfills the major requirements for production of alternative fuels such as feedstock availability, technical feasibility, and economic competitiveness. Together with other renewable biofuels, the use of biodiesel as a subst…
Noise risk assessment in a bottling line of a modern Sicilian winery
2013
In wine industry, bottling is a phase of the production cycle characterized by high levels of noise mostly due to repeated collisions between the bottles. In Italy the Law Decree 81/2008 defined the requirements for assessing and managing noise risk, identifying a number of procedures to be adopted at different noise levels to limit workers exposure. This study aims at evaluating the equivalent and peak noise level inside the bottling plant area of a modern Sicilian winery. In particular, the influence of the working capacity (number of bottles produced per hour) on noise levels was evaluated. We considered three test conditions: T1 with working capacity of 4,000 bottles per hour, T2 with w…
Soil management effect on soil penetration resistance in the vineyard
2013
In environments characterized by steep slopes or arranged in terraces, among the shallow tillage systems, rototilling is extensively used. However, the effect of the repeated use of rototilling has a considerable influence on soil characteristics; it appears finely powdered, soft and without structure. In order to limit these inconveniences, an innovative self-propelled machine equipped with working tools as a spade, to be used in steep slopes or arranged in terraces areas, was designed by the Mechanics Section of the SAF (Scienze Agrarie e Forestali) Department of the University of Palermo in cooperation with Agrotec company, Padua, Italy. The aim of this study is to compare the effects of…
La idea de mente en la crítica de la razón pura
1988
La idea de la mente (Gemüt) hace referencia a esa "facultad radical" de la cual fluyen la sensibilidad y el entendimiento. Propuesta como un "sujeto pensante" por el dinamismo de la razón discursiva, constituye un principio problemático que trasciende la experiencia categorialmente constituida. Sin embargo, es aprehendida por el "sentido interno", traicionada por el sucesividad temporal de los fenómenos. Pensada como una "identidad oculta" que subyace a todas las representaciones, es la idea "regulativa" que sistematiza la razón pura teórica.
Chironomus riparius exposure to fullerene-contaminated sediment results in oxidative stress and may impact life cycle parameters
2015
A key component of understanding the potential environmental risks of fullerenes (C60) is their potential effects on benthic invertebrates. Using the sediment dwelling invertebrate Chironomus riparius we explored the effects of acute (12 h and 24 h) and chronic (10 d, 15 d, and 28 d) exposures of sediment associated fullerenes. The aims of this study were to assess the impact of exposure to C60 in the sediment top layer ((0.025, 0.18 and 0.48) C60 mg/cm2) on larval growth, oxidative stress and emergence rates and to quantify larval body burdens in similarly exposed organisms. Oxidative stress localization was observed in the tissues next to the microvilli and exoskeleton through a method fo…
Comparing soil inventory with modelling: Carbon balance in central European forest soils varies among forest types
2018
Abstract Forest soils represent a large carbon pool and already small changes in this pool may have an important effect on the global carbon cycle. To predict the future development of the soil organic carbon (SOC) pool, well-validated models are needed. We applied the litter and soil carbon model Yasso15 to 1838 plots of the German national forest soil inventory (NFSI) for the period between 1985 and 2014 to enables a direct comparison to the NFSI measurements. In addition, to provide data for the German Greenhouse Gas Inventory, we simulated the development of SOC with Yasso15 applying a climate projection based on the RCP8.5 scenario. The initial model-calculated SOC stocks were adjusted…
Biomagnification of organohalogens in Atlantic salmon (Salmo salar) from its main prey species in three areas of the Baltic Sea
2012
Abstract Factors affecting the biomagnification of organohalogens in Baltic salmon from sprat, herring and three-spined stickleback were assessed in three feeding areas. Second sea-year salmon contained (in fresh weight of whole fish) 79–250 ng g− 1 polychlorinated biphenyls (ΣPCB), 0.9–2.7 pg g− 1 dibenzo-p-dioxins (ΣPCDD), 8–19 pg g− 1 dibenzofurans (ΣPCDF), 96–246 pg g− 1 coplanar PCBs, 2.4–3.6 ng g− 1 polybrominated diphenylethers (ΣPBDE), and 39–136 ng g− 1 Σindicator PCB6. The EU limits for WHO toxic equivalent concentrations in fish feed were already exceeded in one-year-old sprat and herring and were exceeded many-fold in older age groups. The differences in the biomagnification rat…