220 research outputs found
Temi compositivi del verde ornamentale nel collegamento tra città e campagna in area metropolitana bolognese
No full textla progettazione del paesaggio nella situazione attuale, ove tecnoclogie e infrastrutture si stanno ampliando a dismisura, richiede uno sforzo tecnico volto a mitigare situazioni di inquinamento (acustico, chimico, luminoso, ecc.), oltre a non trascurare l'aspetto estetico, sia dal punto di vista intrinseco che estrinsec
“Ceramiche a Veio tra V e III secolo a.C.: i materiali da un pozzo di Piano di Comunità”,
No full textPyrgi, porto e santuario di Caere. Tra conoscenze acquisite e ricerche in corso
No full textIl contributo analizza lo sviluppo delle aree sacre di Pyrgi in parallelo con quello del "Quartiere pubblico-cerimoniale" in corso di scav
Strategies to design high-strength Al alloys with improved L-PBF processability
No full textIn this work, we describe the strategies that we adopted to improve the processability of two high-strength Al alloys produced by Laser Powder bed Fusion (L-PBF). Many alloys of the 2xxx, 6xxx and 7xxx series are indeed very susceptible to hot cracking. To overcome this problem, we explored the effect of different alloying elements on the L-PBF processability of Al-Cu-Mg and Al-Zn-Mg-Cu high-strength alloys. The design of the new alloys was supported by thermodynamic simulations. The microstructure and phase transformations of the materials were investigated by optical and electron microscopy
Monitoring forests in remote areas by IoT measuring systems: the RemoTrees project.
No full textForests ecosystems play a fundamental role in mitigating global warming and associated increasing climatic variability through the feedback of their carbon and water cycles on the global climate system, while being increasingly exposed to dieback and natural disturbances triggered by extreme climate events. The absence of a comprehensive in situ forest monitoring network, particularly in remote regions characterized by strong logistic limitations, poses challenges in tracking forest responses to climate change. Recent strides in IoT technology, satellite IoT connectivity and energy harvesting systems present promising opportunities for the development of novel devices and set-ups for field observations in forest environments. On that note, the EU-funded RemoTrees project (Horizon Europe Research and Innovation Programme under Grant Agreement No. 101086287) aims to design and build an innovative, autonomous in-situ monitoring system suitable for remote forest areas also under extreme physical conditions and able to provide data via satellite communication to a dedicated platform. In this framework, RemoTrees will provide observations of Essential Climate Variables (ECVs) and other key variables including fraction of absorbed photosynthetically active radiation (fAPAR), multispectral measurements of incident, canopy reflected and transmitted solar radiation, tree stem radial growth and motions, sap flow, soil temperature and moisture, besides air temperature and humidity below and above the forest canopy. The resulting data set will be integrated with Earth Observations for the development of use cases on the impact of climate change on forests, demonstrating its usability as a reference for remote sensing products calibration and validation as well as the interoperability and synchronization between in-situ and remote sensing systems according to GEOSS requirements
Monitoring of GHGs flux dynamics at the "Viote" mountain peatland (Eastern Alps, Italy) under climate change pressure
No full textThis presentation focuses on the alpine peatland "le Viote" (46.01 N, 11.04 E, 1560 m asl), located at the centre of a plateau in the Mt. Bondone area, in the eastern Italian Alps (Figure), where the fluxes of methane (CH4) and carbon dioxide (CO2) between the peatland ecosystem and the atmosphere have been measured by chamber technique since summer 2024. The objectives of the current research activities are to analyse the spatial and temporal variability of both GHGs with special attention to CH4 fluxes, considering the response to climatic drivers, the influence of peatland vegetation community types, hydrology and natural and anthropogenic disturbances history. These activities build on 10+ years of CO2 fluxes monitoring by eddy covariance and a more limited dataset of CH4 fluxes, providing a temporal background for detecting flux magnitude changes
Canopy spectral responses of temperate forests to late spring frost and hot drought events assessed with Sentinel-2 NDVI time series
No full textExtreme climatic events (ECEs) are projected to increase due to climate change, but we still have limited understanding of how these events affect the functioning of forest ecosystems. Each species may react differently to ECEs, depending on their ecology, but we lack a regional perspective on these responses. Here we tracked intra-annual changes in the canopy greenness (i.e. NDVI from Sentinel-2 imagery) of 16 tree species growing within 3000 km2 of forests of the Italian Alps. The study region was subject to a late spring frost event in May 2019, and a hot drought in July 2022, allowing us to quantify species responses to ECEs by comparison of seasonal trends in NDVI observed over the period 2018–2024. The effects of 2019 frost were very localized and mainly affected the canopy spectral response and phenology of Fagus sylvatica L. in areas around 1000 m a.s.l.. There, trees had developed buds and some juvenile leaves when frost occurred, resulting in the wilting or dropping of the earliest leaves, and slower green-up phase but no lasting impacts. The hot drought had its largest impact on Quercus ilex L. forests growing at low elevations: there was a clear decrease in canopy greenness from July onwards in 2022, but no residual impacts were observed the following years. At higher elevations, some species had unusually green canopies in response to the heatwave suggesting they benefitted from warmer condition
Development of Al-Cu-Mg and Al-Mg-Si-Zr Alloys with Improved L-PBF Processability
No full textMany Al alloys are susceptible to hot cracking when manufactured by Laser Powder Bed Fusion (L-PBF). In this study, small batches of Al powders were processed using a Reduced Build Volume device to target the optimal chemical composition of the alloy able to suppress hot cracks during solidification. Specifically, batches with increasing content of Cu and Zr were obtained through mechanical mixing of Al-4wt.%Cu-Mg and pure Cu and Al-Mg-Si and Al-Mg-Si-2wt.%Zr powders, respectively. The design strategy based on Cu relies on the segregation of an abundant Al-Al2Cu eutectic phase mixture during final stages of solidification, whereas the Zr addition promotes a fine equiaxed microstructure induced by heterogeneous nucleation of grains triggered by the precipitation of L1(2)-Al3Zr crystal nuclei in the liquid phase. The design of the new alloys was supported by thermodynamic simulations. The microstructures and phase transformations of the alloys were investigated through electron microscopy, X-ray diffraction, and differential scanning calorimetry
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