10,891 research outputs found

    Technical and environmental comparison among different municipal solid waste management scenarios

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    In order to determine the optimal final destination of municipal solid waste, it is necessary to consider both monetary costs and environmental externalities, as well as the local availability of waste-processing industrial infrastructure. The paper examines the results obtained from a technical, economic, and environmental comparison between different scenarios for waste management: in particular, the solutions of gasification and pyrolysis were studied and, afterwards, were compared with direct combustion in incineration plant (from the point of view of the thermal treatment) and final disposal in landfill. In order to perform this analysis, 19 plants operating on full scale were analyzed. The comparison took into account environmental, energy, and economic aspects. From the environmental and energetical point of view, the tool of mass and energy balance was used to address some key environmental aspects. In particular, some indexes were defined in order to perform a comparison among the different analyzed solutions. As concerns the economic point of view, conventional economic criteria were considered. The analysis showed advantages for the examined thermal treatment solutions. The comparison methodology that has been defined can establish a more general useful approach in order to help the definition of the best solution for waste management planning

    Increased urinary volumes in symptomatic Ménière’s Disease

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    Objective. The purpose of the research is to test the measurement of the total urinary volume, induced by the diuretic osmotic action of mannitol, in a group of symptomatic MD patients and in healthy controls. Results. An altered excretory urinary volume after mannitol challenge was observed in symptomatic MD (874.3\u2009\ub1\u2009302.1) compared to healthy volunteers (361.7\u2009\ub1\u2009181.6) (p\u2009=\u20090.0001). This easy and self-administered method might be proposed to replace the analysis of the urinary sugars\u2019 concentration in symptomatic MD patients

    Evaluation of Ca-Based Sorbents for Gaseous HCl Emissions Adsorption

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    The problem of acid gas exhaust emissions treatment has not been fully resolved at present. Dry adsorption of acid gases with alkaline sorbents is currently being investigated, to improve solid sorbents. In this study, 5 types of hydrated lime were characterised and tested. The sorption capacities were measured by means of a system consisting of a feed line (HCl/N2), a thermostatic reactor and a water absorber. The physical characteristics of sorbent samples were also compared. Analyses conducted with scanning electronic microscopy revealed that sample C1 showed uniform particle distribution. Samples C2 and C3 showed the co-presence of fine and coarse particles. Sample C4 showed very fine particles with agglomeration phenomena. In sample C5, fibrous elements were found. Energy dispersive spectrometry (EDS) analyses showed a similar composition of the samples, with the exception of the presence of Mg in some of them. After 30 min of testing, the following differences in sorption capacities with respect to C1 (3.59 mg g−1) were found: C2, −20%; C3, −13%; C4, −17%; C5, −3%. Higher sorption capacities were associated with more uniform particle size distributions. Conversely, agglomeration of fine particles may have adversely affected the performance of sorbents

    Analysis of the emergent climate change mitigation technologies

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    A climate change mitigation refers to efforts to reduce or prevent emission of greenhouse gases. Mitigation can mean using new technologies and renewable energies, making older equipment more energy efficient, or changing management practices or consumer behavior. The mitigation technologies are able to reduce or absorb the greenhouse gases (GHG) and, in particular, the CO2 present in the atmosphere. The CO2 is a persistent atmospheric gas. It seems increasingly likely that concentrations of CO2 and other greenhouse gases in the atmosphere will overshoot the 450 ppm CO2 target, widely seen as the upper limit of concentrations consistent with limiting the increase in global mean temperature from pre-industrial levels to around 2â—¦C. In order to stay well below to the 2â—¦C temperature thus compared to the pre-industrial level as required to the Paris Agreement it is necessary that in the future we will obtain a low (or better zero) emissions and it is also necessary that we will absorb a quantity of CO2 from the atmosphere, by 2070, equal to 10 Gt/y. In order to obtain this last point, so in order to absorb an amount of CO2 equal to about 10 Gt/y, it is necessary the implementation of the negative emission technologies. The negative emission technologies are technologies able to absorb the CO2 from the atmosphere. The aim of this work is to perform a detailed overview of the main mitigation technologies possibilities currently developed and, in particular, an analysis of an emergent negative emission technology: the microalgae massive cultivation for CO2 biofixation

    Cell biology:Collagen secretion explained

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    Cells package proteins into vesicles for secretion to the extracellular milieu. A study shows that an enzyme modifies the packaging machinery to encapsulate unusually large proteins such as collagen

    On historical earthquakes in Switzerland: summary of compilations and investigations

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    Studies of historical earthquakes in Switzerland are contained in monographs, chronological collections of effects and parametric catalogues. The systematic collection of macroseismic material started with the creation of the Swiss Seismological Commission in 1878. All parametric catalogues since 1975 have been prepared for seismic hazard assessment. The most up-to-date investigation of macroseismic data and compilation into a catalogue (ECOS) was made in the 2002 in context of the re-assessment of seismic hazard for nuclear sites

    Economic viability and greenhouse gas (GHG) budget of the biomethane retrofit of manure-operated biogas plants: A case study from Piedmont, Italy

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    The management of livestock manures and slurries noticeably improved since the massive introduction of anaerobic digestion (AD) plants in Italy and other European Union (EU) countries. However, these plants heavily rely on incentives, and the recent switch of European biogas policies from electricity to biomethane potentially threatens the economic viability of manure AD. In this study, three retrofit options are analyzed for an installation in Piedmont (NW Italy) that is currently producing 999 kWel through combined heat and power (CHP). The techno-economic feasibility and the greenhouse gas (GHG) budget is analyzed for each solution. Results show that exploiting current incentives on electricity is vital to fund the retrofit of CHP plants to biomethane. Energy crop and electricity prices, the sale price of biomethane certificates after the end of incentives, and biogas productivity are the critical parameters for the economic profitability of manure AD plants, along with the possibility to deliver biomethane directly to the pipeline grid. This study provides insight to the reconversion of manure AD plants, addressing issues that affect hundreds of installations in Italy and other EU countries
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