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Kernel Density Reconstruction for Lagrangian Photochemical Modelling. Part 1: Model Formulation and Preliminary Tests
In this paper a new approach to photochemical modeling is investigated and a lagrangian particle model named Photochemical Lagrangian Particle Model (PLPM) is described. Lagrangian particle models are a consolidated tool to deal with the dispersion of pollutants in the atmosphere. Good results have been obtained dealing with inert pollutants. In recent years, a number of pioneering works have shown as Lagrangian models can be of great interest when dealing with photochemistry, provided that special care is given in the reconstruction of chemicals concentration in the atmosphere. Density reconstruction can be performed through the so called ''box counting'' method: an Eulerian grid for chemistry is introduced and density is computed counting particles in each box. In this way one of the main advantages of the Lagrangian approach, the grid independence, is lost. Photochemical reactions are treated in PLPM by means of the complex chemical mechanism SAPRC90 and four density reconstruction methods have been developed, based on the kernel density estimator approach, in order to obtain grid-free accurate concentrations. These methods are all fully grid-free but they differ each other in considering local or global features of the particles distribution, in treating the Cartesian directions separately or together and in being based on receptors or particles positions in space
Observations of the Cosmic Background Radiation: Search for spectral distortions and residual polarization
We discuss observations of the CBR presently underway in Milano. We are trying to detect polarization with a sensitivity level of 1/106 and search distortions in the Rayleigh Jeans portion of the frequency spectrum
Polished silver solid amalgam electrode and cationic surfactant as tool in electroanalytical determination of methomyl pesticide.
Trabalho de Conclusão de Curso (Graduação)The polished silver solid amalgam electrode (p-AgSAE) combined with square wave voltammetry (SWV) was
used in the development of an analytical procedure to Methomyl determination in natural water samples. The
experimental and voltammetric parameters were optimized and the use of cationic surfactant cetyltrimethyl
ammonium bromide promoted a considerable change in the kinetic and mechanism of the Methomyl reaction.
Was observed the presence one-single reduction peak, related to a totally irreversible two-electrons transfer,
followed by chemical reaction involving two protons. Analytical parameters (linearity range, analytical curve
equations, correlation coefficient, detection and quantification limits, recovery efficiency, and relative standard
deviation for intraday and interday experiments) were evaluated indicating that the proposed voltammetric
procedure is suitable for determination of Methomyl. The application of the proposed procedure in natural water
analysis indicated high robustness with only simple filtration, without pre-concentration steps, good stability
and suitable sensitivity to determination of Methomyl in natural water samples
Environmental footprint family to address local to planetary sustainability and deliver on the SDGs
The number of publications on environmental footprint indicators has been growing rapidly, but with limited efforts to integrate different footprints into a coherent framework. Such integration is important for comprehensive understanding of environmental issues, policy formulation and assessment of trade-offs between different environmental concerns. Here, we systematize published footprint studies and define a family of footprints that can be used for the assessment of environmental sustainability. We identify overlaps between different footprints and analyse how they relate to the nine planetary boundaries and visualize the crucial information they provide for local and planetary sustainability. In addition, we assess how the footprint family delivers on measuring progress towards Sustainable Development Goals (SDGs), considering its ability to quantify environmental pressures along the supply chain and relating them to the water-energy-food-ecosystem (WEFE) nexus and ecosystem services. We argue that the footprint family is a flexible framework where particular members can be included or excluded according to the context or area of concern. Our paper is based upon a recent workshop bringing together global leading experts on existing environmental footprint indicators
The HTAP_v3 emission mosaic: merging regional and global monthly emissions (2000–2018) to support air quality modelling and policies
This study, performed under the umbrella of the Task Force on Hemispheric Transport of Air Pollution (TF-HTAP), responds to the global and regional atmospheric modelling community's need of a mosaic emission inventory of air pollutants that conforms to specific requirements: global coverage, long time series, spatially distributed emissions with high time resolution, and a high sectoral resolution. The mosaic approach of integrating official regional emission inventories based on locally reported data, with a global inventory based on a globally consistent methodology, allows modellers to perform simulations of high scientific quality while also ensuring that the results remain relevant to policymakers. HTAP-v3, an ad hoc global mosaic of anthropogenic inventories, has been developed by integrating official inventories over specific areas (North America, Europe, Asia including Japan and South Korea) with the independent Emissions Database for Global Atmospheric Research (EDGAR) inventory for the remaining world regions. The results are spatially and temporally distributed emissions of SO2, NOx, CO, non-methane volatile organic compounds (NMVOCs), NH3, PM10, PM2.5, black carbon (BC), and organic carbon (OC), with a spatial resolution of 0.1° × 0.1° and time intervals of months and years, covering the period 2000-2018 (10.5281/zenodo.7516361, Crippa, 2023, https://edgar.jrc.ec.europa.eu/dataset-htap-v3, last access: June 2023). The emissions are further disaggregated into 16 anthropogenic emitting sectors. This paper describes the methodology applied to develop such an emission mosaic, reports on source allocation, differences among existing inventories, and best practices for the mosaic compilation. One of the key strengths of the HTAP-v3 emission mosaic is its temporal coverage, enabling the analysis of emission trends over the past 2 decades. The development of a global emission mosaic over such long time series represents a unique product for global air quality modelling and for better-informed policymaking, reflecting the community effort expended by the TF-HTAP to disentangle the complexity of transboundary transport of air pollution
A MonteCarlo approach for assessing the adequacy of the European gas transmission system under supply crisis conditions
Europe's dependency on non-EU countries' energy supply is sharply increasing. Recently, sudden supply disruption caused by international disputes outside the EU have created serious problems for some EU countries and raised concern in many others. In these situations, it is highly desirable to have a tool to assess possible outcomes of supply disruptions. This paper presents a newly developed model, MC-GENERCIS, aimed to assess the robustness of the EU transnational gas transmission system during both normal and special operating conditions, including high-demand situations and/or a supply shortage. The model has a country-by-country resolution and examines all possible dispatching choices of national TSOs on the basis of a probabilistic MonteCarlo approach. The preliminary validation of the model through its application to the "normal" conditions for the winter 2008-2009 and to the recent supply disruption involving Ukrainian gas transit is also described.Security of gas supply MonteCarlo modeling European gas transmission system
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