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Urban Heat Island, the missing links: smart Monitoring & Evaluation and Citizens engagement
No full textJuly 2023 and October 2023 have been the hottest than ever at global level. Last summer Southern Europe experienced extreme heat, breaking many local high temperature records. Climate warming and heat peaks are exacerbating the Urban Heat Island (UHI) effect, the relative warmth of a city compared to surrounding rural areas. Solutions able to mitigate urban overheating can prevent energy demand for cooling increase (there might be up to 14 billion items of cooling equipment in 2050!) and generate multiple effects on comfort and health, air and water quality and biodiversity, but also on urban regeneration and socio-economic development. So far main UHI measures in Sustainable Energy and Climate Action and/or Adaptation and Resiliency Plans seem to lack a suitable integrated and participated approach as well as monitoring and evaluation (M&E) strategies. Yet some exemplary plans do exist and can show the way to new approaches. Opportunities from digitalisation, smart city technologies and citizens availability to participate in planning and data collection remain underexploited. Mobile computing and mobile-based technologies allowing for participatory planning tools and co-creation, citizen science, volunteered geographic information (VGI) are integrating innovative concepts to increase UHI awareness, generate big-data and empower cities and communities to reduce the UHI effect. But only a few smart cities, – like Barcelona, currently combine bottom-up data, evidence-based planning and M&E. Reliability, privacy and interoperability constraint impede the spread of such applications. After recalling the state of the art of M&E and participation in climate adaptation plans, the paper provides some examples of urban overheating mitigation policies and actions encompassing these two aspects. Then, it briefly mentions what advancements smart cities applications can offer: for instance, greatly simplified UHI estimations through mobile transects for a widespread availability of ambient temperature data without the need for costly equipment and many hours of dedication by the researchers. Finally, the paper showcases a possible participatory M&E approach embedded in the new Rome adaptation strategy and inspired by the selected best practices. This second part is based on findings from a field study in municipal nursery schools, where an outdoor evaporative cooling system may locally reduce the outdoor air up to 5 °C and ensure the thermal comfort conditions for the majority of the interviewees who had before experienced overheating outside of the misted zone. The success of the initiative kicked off the idea of implementing a program for the real time monitoring and alerting of cool shelters in the city of Rome, by integrating an existing Smart City Platform (SCP)
PNIPAM microgel coatings of LiF crystal radiation detectors
Get PDFThin films of poly(N-isopropylacrylamide) (PNIPAM) microgels have recently attracted significant attention as promising candidates for creating switchable interfaces in biomedical and biotechnological applications. In this study, microgel films are proposed as smart coatings for photoluminescent solid-state radiation detectors based on lithium fluoride (LiF). Understanding the impact of the solid substrate is crucial for customising and refining microgel coatings for specific applications. To investigate the effects of surface quality, microgel size, and particle concentration on the properties of microgel films, PNIPAM microgels were spin-coated onto LiF crystal surfaces and characterised through wettability measurements, UV-Vis-NIR spectrophotometry, and Atomic Force Microscopy. This approach enabled effective control over the optical and morphological properties of the films, paving the way for the development of hybrid and potentially biocompatible radiation detectors using PNIPAM microgel films
Unbalanced core detector (UCD): a novel direct-reading dosimeter for FLASH radiotherapy
Get PDFFLASH radiotherapy (FRT) is a novel radiotherapy technique based on dose rates that are several orders of magnitude greater than those used in conventional radiotherapy (40 Gy/s vs. 0.5–5 Gy/min). FRT is still in its preclinical and early clinical stage of development. However these studies indicate that FRT is more effective in sparing normal tissues from radiation-related side effects, as compared to conventional radiotherapy. This is the so-called "FLASH effect" and was observed with multi-MeV electron beams. Before FRT is made available to humans, more basic research is needed to fully understand its radiobiology fundamentals. Meanwhile, suitable radiation sources and dosimetric tools are gradually becoming available. Within this framework, INFN-LNF developed the Unbalanced Core Detector (UCD), a novel type of electron dosimeter designed to operate in the FRT domain. UCD main characteristics are the nearly isotropic response, the independence from the electron energy, the very high radiation resistance, the linearity up to dose rates of MGy/s and the possibility to record the time evolution of a single radiation pulse. UCD was tested using 7 and 9 MeV electron beams produced with the ElectronFlash accelerator from Sordina IORT Technologies (SIT S.p.A.) in Aprilia, Italy. UCD was used to measure dose distributions in a water phantom. The results well compare to those obtained with a flashDiamond detector from PTW
Nonlinear dynamics of the reversed shear Alfvén eigenmode in burning plasmas
No full textIn a tokamak fusion reactor operated at steady state, the equilibrium magnetic field is likely to have reversed shear in the core region, as the noninductive bootstrap current profile generally peaks off-axis. The reversed shear Alfvén eigenmode (RSAE) as a unique branch of the shear Alfvén wave in this equilibrium, can exist with a broad spectrum in wavenumber and frequency, and be resonantly driven unstable by energetic particles (EP). After briefly discussing the RSAE linear properties in burning plasma condition, we review several key topics of the nonlinear dynamics for the RSAE through both wave-EP resonance and wave-wave coupling channels, and illustrate their potentially important role in reactor-scale fusion plasmas. By means of simplified hybrid MHD-kinetic simulations, the RSAEs are shown to have typically broad phase space resonance structure with both circulating and trapped EP, as results of weak/vanishing magnetic shear and relatively low frequency. Through the route of wave-EP nonlinearity, the dominant saturation mechanism is mainly due to the transported resonant EP radially decoupling with the localized RSAE mode structure, and the resultant EP transport generally has a convective feature. The saturated RSAEs also undergo various nonlinear couplings with other collective oscillations. Two typical routes as parametric decay and modulational instability are studied using nonlinear gyrokinetic theory, and applied to the scenario of spontaneous excitation by a finite amplitude pump RSAE. Multiple RSAEs could naturally couple and induce the spectral energy cascade into a low frequency Alfvénic mode, which may effectively transfer the EP energy to fuel ions via collisionless Landau damping. Moreover, zero frequency zonal field structure could be spontaneously excited by modulation of the pump RSAE envelope, and may also lead to saturation of the pump RSAE by both scattering into stable domain and local distortion of the continuum structure
Characterisation of the neutron field for streaming analyses in TT operations at JET
No full textAssessing radiation fields in the biological shield penetrations of fusion reactors is a challenging task. At the Joint European Torus (JET) the neutron field at larger distances from the torus has been calculated and measured. JET operated in 2021–22 with a tritium-tritium plasma and neutronics experiments were performed for validating in a real fusion environment the neutronics codes and nuclear data applied in ITER nuclear analyses. In particular, the fluence of neutrons passing through the penetrations of the JET vacuum vessel and the torus hall was measured and compared with calculations in order to assess the capability of state-of-the-art numerical tools to correctly predict the radiation streaming in large and complex geometries. The neutron fluence was monitored at several locations inside the torus hall at larger distances from the tokamak with activation foils and thermo-luminescent detectors. The calculations have been performed in a two-step process using the deterministic code ADVANTG to determine the variance reduction parameters and with MCNP for subsequent calculation of the neutron field with the Monte Carlo method. The paper presents results of calculations and the first comparison to experimentally obtained values
Uncertainty and Sensitivity Analyses for Postulated Severe Accidents of Reference PWRs and SMRs in the Frame of the IAEA CRP and Relevant Insights
No full textIn 2019, the International Atomic Energy Agency (IAEA) launched the 5-year Cooperative Research Project (CRP) I31033 to advance the understanding and characterization of sources of uncertainty and to investigate their effects on the key figures of merit (FOMs: response parameters of interest) of the severe accident code predictions for water-cooled reactors. Twenty-two institutions from 18 member states participated in the CRP, and as a result, TECDOCs are being developed for the relevant benchmark exercises. The respective TECDOCs address a specific exercise and outline relevant research results pointing to best practices for the uncertainty and sensitivity analyses of the currently available severe accident codes. For the uncertainty analysis exercise, the CRP participants defined their own analysis scope and framework, including target plant, severe accident code, accident scenario, and relevant FOMs. According to each respective framework, participants independently carried out their own exercise, including plant modeling and nodalization, simulation of reference cases, and relevant uncertainty and sensitivity analyses. Finally, general conclusions were made based on an analysis of the results in view of the best-practice application of the uncertainty and sensitivity methods. Among them, this paper summarizes the main results of the uncertainty and sensitivity exercise performed for both pressurized water reactors and integral light water small modular reactors in the frame of the IAEA CRP with relevant insights
Update of the 5 MW Beam-on-Target Requirements for improvement of the materials irradiation performance at IFMIF-DONES
Get PDFIFMIF-DONES is a facility under construction in Granada, whose main goal is the validation and characterization of materials under a fusion prototypic irradiation field. This field is created by the interaction of a high energy intense continuous deuteron beam and a flowing liquid lithium target. The requirements imposed on the beam at the interaction point are a complex trade-off among the scientific experimental needs for the materials irradiation defined at the top-level requirements (20 dpa in a volume of 0.3 dm3 and 50 dpa in 0.1 dm3), and the technical constraints of several systems such as the Accelerator Systems, the Lithium Systems, and the Test Systems. Recent simulations with the initial definition of beam-on-target requirements showed the necessity of redefining them in order to fulfill the irradiation needs. This contribution will address the main challenges to gather the inputs for the definition and reassessment of the beam-on-target requirements. A comparison detailing the main changes compared to the previous ones will be given, together with a short overview of the studies ongoing by different systems to analyze the impact of each beam-on-target requirements on the performance of the whole facility
Removal of Organic Materials from Mytilus Shells and Their Morphological and Chemical-Physical Characterisation
Get PDFA simple and effective method to eliminate the organic component from mussel shells is presented. It is based on the use of hot hydrogen peroxide. Mollusc shells are composite materials made of a calcium carbonate matrix with different polymorphs and numerous biomacromolecules. The described method was used on mussel shells, but it is generalisable and allows the complete removal of these organic components, without altering the inorganic part. Specimens were kept in a H2O2 40% bath for few hours at 70 °C. The organic layers found on the faces of the shells were peeled away in this way, and biomacromolecules were degraded and removed. Their fragments are soluble in aqueous solution. This easily permits the chemical-physical characterisation and the study of the microstructure. The quality of calcite and aragonite microcrystals of biogenic origin is very high, superior to that of materials of geological or synthetic origin. This may suggest various industrial applications for them. Calcium carbonate is a useful precursor for cements and other building materials, and the one obtained in this way is of excellent quality and high purity
Studies on Morphological Evolution of Gravure-Printed ZnO Thin Films Induced by Low-Temperature Vapor Post-Treatment
Get PDFIn recent years, the morphology control of semiconductor nanomaterials has been attracting increasing attention toward maximizing their functional properties and reaching their end use in real-world devices. However, the development of easy and cost-effective methods for preparing large-scale patterned semiconductor structures on flexible temperature-sensitive substrates remains ever in demand. In this study, vapor post-treatment (VPT) is investigated as a potential, simple and low-cost post-preparative method to morphologically modify gravure-printed zinc oxide (ZnO) nanoparticulate thin films at low temperatures. Exposing nanoparticles (NPs) to acidic vapor solution, spontaneous restructuring pathways are observed as a consequence of NPs tending to reduce their high interfacial energy. Depending on the imposed environmental conditions during the treatment (e.g., temperature, vapor composition), various ZnO thin-film morphologies are produced, from dense to porous ones, as a result of the activation and interplay of different spontaneous interface elimination mechanisms, including dissolution–precipitation, grain boundary migration and grain rotation–coalescence. The influence of VPT on structural/optical properties has been examined via XRD, UV–visible and photoluminescence measurements. Controlling NP junctions and network nanoporosity, VPT appears as promising cost-effective, low-temperature and pressureless post-preparative platform for preparing supported ZnO NP-based films with improved connectivity and mechanical stability, favoring their practical use and integration in flexible devices
Monitoring Gas Emissions in Agricultural Productions through Low-Cost Technologies: The POREM (Poultry-Manure-Based Bio-Activator for Better Soil Management through Bioremediation) Project Experience
No full textAgricultural production or rural activities can involve the emission of unpleasant gases, malodors, or most commonly, greenhouse gases. In any case, the control and monitoring of such emissions in rural, unattended, and remote locations represent an issue in need of addressing. In this article, the monitoring of gases produced by a poultry manure depot and performed by devices based on low-cost gas sensors in the context of the POREM (poultry-manure-based bio-activator for better soil management through bioremediation) project is reported. This experience has shown that the continuous and real-time monitoring of gas emissions in an unattended, remote, and rural area, where it is unfeasible to employ expensive, professional instruments, can be successfully performed by low-cost technologies. Two portable monitoring units developed in the laboratory and based on low-cost gas sensors were used to provide indications about the concentrations of NH3, CH4, H2S, and CO2. During this experiment, two monitors were deployed: the first one was placed in the manure storage depot, while the second one was deployed out of the storage site to compare the gas concentrations related to the outdoor environment with the gas emissions coming from the manure. Both devices were wirelessly linked to the Internet, even though the radio signal was weak and unstable in that area. This situation provided us with the opportunity to test a particular protocol based on sending and receiving e-mails containing commands for the remote machines. This experiment proved the effectiveness of the use of low-cost devices for gas emission monitoring in such particular environments