Cryogenic setup for electron counting experiments

This technical report describes the electrical and mechanical configuration of a system devoted to the mise en pratique of the DC electrical current in the range 100 fA - 100 pA. A commercial dilution refrigerator (Leiden Cryogenics B.V. MicroKelvin-50), installed in the Cryogenic Laboratory (b302b @ INRiM), represents the starting point of the measurement setup. The instrument allows the achievement of a base temperature near 30 mK, this latter being necessary for the implementation of a single-electron-transistors- device-based current source. The entire measurement set up has been designed to fulfill the strict low-noise ambient requirements reaching a state-of-the-art configuration in the field of quantum metrology of low currents. The problem of the transport of the electrical signals from room temperature electronics (isolated voltage sources, low-noise current amplifier..) to the devices located in the coldest region of the refrigerator has been faced with a multi-stage modular approach. In this view several custom components have been designed and developed, keeping in mind the metrological scope of the whole experiment

The Italian National Air Pollution Control Programme: Air Quality, Health Impact and Cost Assessment

Air pollution is the primary environmental cause of death globally. To improve air quality and reduce health impacts, the National Emission Ceilings Directive requires Member States of the European Union to provide National Air Pollution Control Programmes, including emission reduction measures aimed to achieve binding commitments for the years 2020 and 2030. Integrated assessment models are pivotal to assess the reduction of pollutants concentrations determined by measures implemented or foreseen for emission reduction. Here we discuss scenarios elaborated for year 2030 in the Italian National Air Pollution Control Programme, considering 2010 as reference year. The two scenarios, “With Measures” and “With Additional Measures”, show a significant reduction of the pollutants concentration, namely PM2.5, NO2 and O3. The scenarios are here also used to provide an integrated approach for calculating the effect of the program on health impacts (mortality) and related costs. Avoidable attributable cases and associated costs are here reported at both the national and regional level and provide a significant framework to assess air-pollution reduction measures with an integrated approach. The procedure proposed may be therefore further developed and applied to assess the overall positive benefits (environmental, health and economic) determined by air-pollution control plans or other integrated policies targeting air quality, energy and climate goals

Cryogenic setup for electron counting experiments

This technical report describes the electrical and mechanical configuration of a system devoted to the mise en pratique of the DC electrical current in the range 100 fA - 100 pA. A commercial dilution refrigerator (Leiden Cryogenics B.V. MicroKelvin-50), installed in the Cryogenic Laboratory (b302b @ INRiM), represents the starting point of the measurement setup. The instrument allows the achievement of a base temperature near 30 mK, this latter being necessary for the implementation of a single-electron-transistors- device-based current source. The entire measurement set up has been designed to fulfill the strict low-noise ambient requirements reaching a state-of-the-art configuration in the field of quantum metrology of low currents. The problem of the transport of the electrical signals from room temperature electronics (isolated voltage sources, low-noise current amplifier..) to the devices located in the coldest region of the refrigerator has been faced with a multi-stage modular approach. In this view several custom components have been designed and developed, keeping in mind the metrological scope of the whole experiment

Implementation of an On-Line Reactive Source Apportionment (ORSA) Algorithm in the FARM Chemical-Transport Model and Application over Multiple Domains in Italy

A source apportionment scheme based on gas and aerosol phase reactive tracers has been implemented in the chemical-transport model FARM, to efficiently estimate contributions of different sources to ambient concentrations. The on-line scheme deals with all the main processes that the chemical species undergo in the model, to enhance consistency with the calculation of bulk concentrations. The fate of precursors through gas-phase chemical reactions is followed by an efficient solver that determines their incremental reactivity, while the contributions to the secondary particulate species from their gaseous precursors is determined by assuming the thermodynamic equilibrium between the two phases. The paper details the new employed methodologies and illustrates the application of the apportionment scheme (based on 6 source sectors) to PM10 and O3, simulated on three domains of different dimensions in Italy, all sharing the same horizontal resolution and a common region (Lombardy). Spatial patterns of results show, on average, a relevant contribution of heating on PM10 concentration in January, with local hotspots dominated by road traffic. Contributions appear consistent in the three simulated domains, apart from the boundary conditions, influenced by the dimension of the domain. Hourly series of contributions to O3 concentrations in July at three selected sites show the dominance of boundary conditions, underlining the large scale of O3 formation. Finally, for PM10 components, the resulting sectorial contributions are compared with the impacts computed via the brute force method, showing that results are similar for elemental carbon and sulfate, while they are different for nitrate and ammonium, due to a different allocation of contributions and impacts between the methods. Each approach responds in principle to a different purpose, and their combined use provides possibly a wide set of information useful for addressing the different air quality management needs