Safety assessment of scenarios triggered by accidental seawater immersion of lithium batteries in innovative naval applications

The request of lithium-ion batteries in naval applications features an increasing trend due to the need of high performance energy storage devices. Beside the hazard of runaway when the battery is crushed or overcharged, the naval environment poses additional safety issues due to the possible immersion with seawater of the battery room following accidental flooding. In such a case, seawater electrolysis may generate hydrogen and chlorine, thus giving rise to an explosive and toxic mixture in a confined environment. In this study, a quantitative safety assessment of the possible accidental scenarios induced by seawater electrolysis in battery rooms is performed. The analysis is based on i) the deterministic evaluation of the hazardous gases development according to a three-dimensional physically-based electrochemical model and ii) the discussion of possible prevention and mitigation measures. The dynamics of gas release and the time required to produce an explosive atmosphere are evaluated as a function of the level of seawater for a reference case study. The outcomes of the study support the safety assessment of accidental scenarios induced by seawater electrolysis in naval applications and provide indications on the effectiveness of hazard reduction measures. More specifically, the study reveals that a proper electric insulation of the surface of battery terminals represents a sensible mitigation strategy to reduce the severity of explosions in addition to the ventilation of the battery room

Damage models for storage and process equipment involved in flooding events

The present study focuses on the accidents caused by the impact of floods on storage and process equipment. This type of accident is classified as a NaTech (Natural-Technological) event and resulted in severe consequences in several past accidents. A methodology was developed for the determination of vulnerability models aimed at the estimation of equipment damage probability on the basis of severity or intensity parameters of the flooding. A mechanical model was developed, based on the comparison between the flooding intensity and the resistance of a vessel and/or its support. Simplified vulnerability functions were derived. Finally, a case-study was set up and analysed to show the potentialities of the methodology and the implementation of results in quantitative risk analysis. © 2013, AIDIC Servizi S.r.l

Domino effects related to explosions in the framework of land use planning

The present study analyses the possible escalation due to the damage of industrial equipment containing hazardous materials loaded by pressure waves produced either by an accidental source as a Vapour Cloud Explosion, or by a voluntary external attack such as the explosion of a TNT charge located nearby the industrial facility. The results obtained evidence the similarities and the differences for the two explosion sources in terms of structural damage, loss of containment and of expected impacts on the population. In particular, a specific vulnerability assessment was carried out defining a case-study in order to evidence the different potential impact of domino effect triggered by internal process causes respect to escalation scenarios caused by external acts of interference. © 2013, AIDIC Servizi S.r.l

Efficacy of topical imiquimod 3.75% in the treatment of actinic keratosis of the scalp in immunosuppressed patients: our case series

AbstractBackground: Actinic keratoses (AK) represent common cutaneous lesions, appearing in 'Field cancerization areas' and potentially evolving toward invasive neoplasm. Immunosuppressed patients ..

Proper holomorphic mappings between symmetrized ellipsoids

We characterize the existence of proper holomorphic mappings in the special class of bounded $(1,2,...,n)$-balanced domains in $\mathbb{C}^n$, called the symmetrized ellipsoids. Using this result we conclude that there are no non-trivial proper holomorphic self-mappings in the class of symmetrized ellipsoids. We also describe the automorphism groupof these domains.Comment: 10 pages, some modification

Accident scenarios caused by lightning impact on atmospheric storage tanks

In recent years, severe natural events raised the concern for the so-called NaTech (natural-technological) accident scenarios: Technological accidents caused by the impact of a natural event on an industrial facility or infrastructure. Severe scenarios typical of the process industry, as fires, explosions, toxic releases, and water pollution were reported as the consequence of natural events in industrial areas. The historical analysis of accidental scenarios triggered by lightning shows that the impact of a lightning on an atmospheric storage tank might be the initiating event of a severe accident. The analysis of past accident evidences that several alternative damage mechanisms and accident scenarios may follow lightning impact. Although lightning hazard is well known and is usually considered in the risk analysis of chemical and process plants, well accepted quantitative procedures to assess the contribution of accidents triggered by lightning to industrial risk are still lacking. In particular, the approaches to the assessment of accident scenarios following lightning strike are mostly based on expert judgment. In the present study, a detailed methodology is presented for the assessment of quantified event trees following lightning impact on an atmospheric tank. Different damage mechanisms have been considered in order to assess the frequencies of loss of containment due to lightning strikes. The results were used in a case study to assess the overall risk due to lightning impact scenarios in typical lay-outs of tank farms of oil refineries. Copyright © 2013, AIDIC Servizi S.r.l

3-iodothyronamine affects thermogenic substrates’ mobilization in brown adipocytes

We investigated the effect of 3-iodothyronamine (T1AM) on thermogenic substrates in brown adipocytes (BAs). BAs isolated from the stromal fraction of rat brown adipose tissue were exposed to an adipogenic medium containing insulin in the absence (M) or in the presence of 20 nM T1AM (M+T1AM) for 6 days. At the end of the treatment, the expression of p-PKA/PKA, p-AKT/AKT, p-AMPK/AMPK, p-CREB/CREB, p-P38/P38, type 1 and 3 beta adrenergic receptors (β1–β3AR), GLUT4, type 2 deiodinase (DIO2), and uncoupling protein 1 (UCP-1) were evaluated. The effects of cell conditioning with T1AM on fatty acid mobilization (basal and adrenergic-mediated), glucose uptake (basal and insulin-mediated), and ATP cell content were also analyzed in both cell populations. When compared to cells not exposed, M+T1AM cells showed increased p-PKA/PKA, p-AKT/AKT, p-CREB/CREB, p-P38/P38, and p-AMPK/AMPK, downregulation of DIO2 and β1AR, and upregulation of glycosylated β3AR, GLUT4, and adiponectin. At basal conditions, glycerol release was higher for M+T1AM cells than M cells, without any significant differences in basal glucose uptake. Notably, in M+T1AM cells, adrenergic agonists failed to activate PKA and lipolysis and to increase ATP level, but the glucose uptake in response to insulin exposure was more pronounced than in M cells. In conclusion, our results suggest that BAs conditioning with T1AM promote a catabolic condition promising to fight obesity and insulin resistance