IRIS Università degli Studi dell'Aquila
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Innovative sulfation strategy for efficient recovery of rare earth elements from spent fluorescent lamp powder
Get PDFThe recovery of rare earth elements (REEs) from spent fluorescent lamp phosphors is essential for resource sustainability and circular hydrometallurgy. While yttrium (Y) and europium (Eu) can be recovered through simple acid leaching, extracting cerium (Ce), lanthanum (La), and terbium (Tb) from green phosphors is challenging due to their resistance to dissolution. This study presents a novel sulfation-based process at relatively low temperatures to selectively recover REEs, particularly Tb, while minimizing energy consumption and environmental impact by preventing sulfuric acid and mercury evaporation. Initially, sulfuric acid leaching selectively recovered most of Y and Eu, leaving other REEs in the solid residue. These elements were then precipitated as a nearly pure REE oxalate mixture (>99 % purity). The effects of sulfation time, temperature, and acid-to-powder weight ratio were optimized using Response Surface Methodology (RSM). Sulfation at 150 °C for 5 h enabled the recovery of nearly 100 % Ce and Gd, 98.01 % La, and 98.15 % Tb through water leaching. The mixed oxalate precipitate, enriched in La, Ce, and Tb, exhibited >98 % purity. SEM analysis revealed the formation of flower-like mixed REE oxides after calcination. This process achieved high recovery efficiencies of 99.98 % Y, 100 % Eu, 99.92 % Ce, 97.22 % La, 97.68 % Tb, and 99.97 % Gd. By using only sulfuric and oxalic acid, it aligns with sustainable hydrometallurgy, reducing chemical diversity and enabling acid regeneration. This study provides an efficient, environmentally friendly approach for REE recovery from phosphor waste
Robust Backstepping Super-Twisting MPPT Controller for Photovoltaic Systems Under Dynamic Shading Conditions
Get PDFThe Signalled Licking/Avoidance of Punishment (SLAP) Paradigm in Rats: Capacity for Insight Between Goal Conditioning and Signalling Contingencies
No full textIn developmental-age
kids with specific-learning-
disabilities
(SLD), functional illiteracy entails poor logical reasoning; in those
with attention-deficit/
hyperactivity disorder (ADHD), a deficit in prospective memory results in difficulty executing previously
planned actions. We model this SLD and/or ADHD construct in the rat via the signalled-licking/
avoidance-of-
punishment
protocol
(SLAP): We aim to study to assess rats' ability to merge two independently learned notions (one Pavlovian and one instrumental)
and their deliberate exploitation. Rats were tested in Skinner boxes with a water-dispenser
and lickometer. The ‘Flash’
paradigm consists of 30-min
daily sessions, in which 5-min
safe phases (i.e., sound and light off, signalled free-drinking)
are
intertwined by 1-min
unsafe phases (i.e., sound and light on). If subjects drink during unsafe phases, a mild footshock is released:
Rats learn to withhold drinking. The ‘Allow’ paradigm starts and stays in the unsafe phase. Rats can shift to a 2-min
safe
phase through a single nose poke in the active-hole.
The possibility to exert control over the environment, via seeking dark-and-
silence
(the predictive contingencies) as deliberate goal, is an unexplored construct in rats. In data from the ‘Flash’ paradigm, a
greater number of licks/h during safe phases is confirming that rats easily understand classical passive-avoidance
contingencies.
Findings from the ‘Allow’ paradigm indicate increased inefficacious nose pokes/h during safe phases, compared to unsafe ones.
This is clearly suggesting that rats associate the change of phase with an outcome of their own input into the active nose-poking
device. However, rats do not understand the ‘potential’ for instrumental exploitation of their nose pokes. As such, no significant
inferences were drawn across the two independent associative notions. Neurobiology of this putative ‘insight’ capability may rely
on limbic-striatal-
cortical
networks. Impairments in the latter may be involved in deficits of prospective memory (in ADHD),
and/or impairments in logic skills (in SLD). The SLAP protocol may offer insights on basic neurobiology as well as modulatory
effects thereon of pharmacological molecules
The Approximation of the Quadratic Porous Medium Equation via Nonlocal Interacting Particles Subject to Repulsive Morse Potential
No full textWe propose a deterministic particle method for a one-dimensional nonlocal equation with interactions through the repulsive Morse potential. We show that the particle method con verges as the number of particles goes to infinity towards weak measure solutions to the nonlocal equation. Such a results is proven under the assumption of initial data in the space of probability measures with finite second moment. In particular, our method is able to capture a measure-to-(Formula Presented)infty smoothing effect of the limit equation. Moreover, as the Morse potential is rescaled to approach a Dirac delta, corresponding to strongly localized repulsive interactions, the scheme becomes a particle approximation for the quadratic porous medium equation. We show that in the joint limit (localized repulsion and increasing number of particles) the reconstructed density converges to a weak solution of the porous medium equation. The strategy relies on various estimates performed at the particle level, including Lpestimates and an entropy dissipation estimate, which benefit from the particular structure of our particle scheme and from the absolutely continuous reconstruction of the density from the particle locations
PERSONALITY AND WELL-BEING: A PILOT STUDY IN PROTECTED AREAS AND NATIONAL PARKS IN ITALY
No full textPrevious research in the psychology field has primarily focused on the Big Five personality traits and daily psychological well-being. However, there is a significant lack of research on trait mindfulness and well-being experienced in specific green environments. The present research aims to address how trait mindfulness affects well-being experienced in protected areas and national parks. This study was carried out in different Italian protected areas and national parks, which are well-known for preserving biodiversity and offering opportunities for social and sustainable activities that can foster individual well-being.
The sample consisted of 71 participants (Mean=42.85; SD=14.29; 42F). Participants completed a set of self-report measures, including a short socio-demographic questionnaire, the individual and collective pro-environmental scale, the Big Five 10, the Cognitive and Affective Mindfulness Scale Revised, and an ad hoc scale on well-being in protected areas and national parks. After controlling for age, gender, education, personal and collective pro-envioronmental behaviours, and Big Five, the analysis indicated that trait mindfulness positively predicted well-being in protected areas and national parks (B =0.581, p<0.01).
This evidence suggests that people with high levels of trait mindfulness, characterised by an enhanced ability to stay present and aware, reported a higher experience of well-being when visiting natural environments. This implies that trait mindfulness may amplify the restorative effects of nature, probably due to a heightened capacity to engage with the surrounding environment. Our findings suggest that promoting mindfulness capacity and spending time in protected areas can maximise psychological benefits, making a valuable support for clinical interventions
Sustainable Regeneration of Urban Centers: Strategic Guidelines of Intervention
No full textIn line with European Green Deal and European
directives, cities have been the subject of interventions aimed at
energy transition, sustainable urban development and
decarbonization, through the exploitation of renewable sources,
self-production systems and innovative technological solutions.
However, the field related to urban spaces is still poorly
investigated and lacks consolidated methodologies for
sustainable planning or regeneration. This paper presents an
analysis of ten case studies that propose sustainable urban
regeneration interventions for small and medium-sized urban
centers. Through the analysis, various areas of intervention are
highlighted, such as service networks and infrastructure, urban
spaces and mobility, where interventions with different goals
and design solutions are proposed. The various issues addressed
highlight the multipurpose meaning of sustainability and the
possibility of intervention in different areas of urban centers.
The results contribute to the definition of strategic lines of
intervention in various areas based on the main themes, such as
decarbonization, recovery and inclusiveness, providing
guidance for sustainable planning of the urban environment
Imagenomics and Ventricular Arrhythmia
Get PDFBackground: Imagenomics is an emerging clinical framework that combines advanced imaging and genetic profiling to refine risk stratification and advance precision medicine in the management of ventricular arrhythmias. Case Summary: A 43-year-old woman presented with palpitations and presyncope. Ambulatory electrocardiogram revealed frequent premature ventricular contractions and nonsustained ventricular tachycardia, consistently initiated by a premature ventricular contraction with distinct morphology. Cardiac magnetic resonance scan identified a nonischemic scar in the basal inferolateral segment of the left ventricle, with a protected conduction corridor of heterogeneous tissue within the border zone. Electroanatomic mapping confirmed a critical isthmus that was anatomically colocalized with the cardiac magnetic resonance–defined corridor. Programmed ventricular stimulation induced sustained monomorphic ventricular tachycardia that degenerated into ventricular fibrillation, necessitating implantable cardioverter-defibrillator placement. Genetic analysis revealed a heterozygous, likely pathogenic TECRL variant, associated with catecholaminergic polymorphic ventricular tachycardia type 3. Discussion: This case highlights a composite arrhythmogenic mechanism shaped by myocardial scar substrate, protected conduction architecture, and inherited susceptibility
Multi-scale contrast-to-noise ratio (MS-CNR): a novel metric for quantitative defect characterisation without manual region specification
No full textIn numerous research domains where imaging plays a pivotal role in analysing specific objects or processes, it is crucial to quantitatively evaluate the performance of acquisition systems and processing algorithms in differentiating the target from its background. This paper presents the Multi-Scale Contrast-to-Noise Ratio (MS-CNR) metric, a novel tool for precise defect quantification across various imaging modalities. The MS-CNR metric employs the Laplacian of Gaussian (LoG) operator to analyse contrast at multiple scales, allowing for effective quantitative defect characterisation without relying on predefined regions for defects or noise. Through comprehensive evaluation with synthetic and real data, the MS-CNR metric demonstrates a strong correlation with human visual perception and other well-established SNR metrics. It provides consistent and reproducible results, outperforming traditional SNR metrics that may be affected by specific types of noise. The MS-CNR metric’s robust performance and alignment with visual assessments make it a valuable addition to imaging analysis, offering a reliable and automated approach for evaluating defect visibility
Thermal Environment Analysis for Energy Efficiency and Heritage Conservation via Regression Trees and Random Forests
Get PDFPreserving historic buildings with significant cultural heritage presents complex challenges, requiring a careful balance between energy efficiency, conservation of artworks, and visitor comfort. This study focuses on the 12th-century Church of Santa Maria Annunziata in L’Aquila, Italy, where maintaining stable environmental conditions is crucial for safeguarding valuable paintings and wooden artifacts. Despite the sensitivity of these artworks, the church currently operates without a dedicated HVAC system. To analyze the indoor thermal environment, a multidisciplinary approach was adopted, incorporating on-site measurements, statistical evaluation, and predictive modeling over different forecasting periods. The results indicate that temperature levels within the church often stray from the ideal range for artwork conservation. As a result, there is an urgent need to assess and implement an appropriate HVAC solution to create a more stable indoor microclimate