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

The performance of inorganic passive fire protections: An experimental and modelling study

The installation of fireproofing materials on equipment and structures is a widely applied and effective solution for the protection of critical process elements against severe fires, in order to prevent possible damages escalation. The choice and design of fireproofing materials is crucial for granting adequate performances. As a matter of fact, properties such as, among others, thermal conductivity and density change substantially when the material is exposed to severe temperatures. In the present study, a methodological approach, integrating experimental and modelling activities, was proposed. Focus was set on a particular class of PFP: inorganic fireproofing materials. A reference set of commercial PFP materials (rock wool, glass wool, silica blanket, etc.) was selected. Small scale experiments allowed determining the variation of the most relevant thermal properties of the coatings and to obtain detailed correlation models for their description. A finite element model (FEM) was developed in order to reproduce the behaviour of real scale equipment exposed to fire and to provide a sound design of the fire protection system

Thyroid Hormone, Thyroid Hormone Metabolites and Mast Cells: A Less Explored Issue.

Mast cells are primary players in immune and inflammatory diseases. In the brain, mast cells are located at the brain side of the blood brain barrier (BBB) exerting a crucial role in protecting the brain from xenobiotic invasion. Furthermore, recent advances in neuroscience indicate mast cells may play an important role in glial cell-neuron communication through the release of mediators, including histamine. Interestingly, brain mast cells contain not only 50% of the brain histamine but also hormones, proteases and lipids or amine mediators; and cell degranulation may be triggered by different stimuli activating membrane bound receptors including the four types of histaminergic receptors. Among hormones, mast cells can store thyroid hormone (T3) and express membrane-bound thyroid stimulating hormone receptors (TSHRs), thus suggesting from one side that thyroid function may affect mast cells function, from the other that mast cell degranulation may impact on thyroid function. In this respect, the research on hormones in mast cells is scarce. Recent pharmacological evidence indicates the existence of a non-genomic portion of the thyroid secretion including thyroid hormone metabolites. Among which the 3,5 diiodothyronine (3,5-T2), 3-iodothyroanamine (T1AM) and 3-iodothyroacetic acid (TA1) are the most studied. All these compounds are endogenously occurring and found to be increased in inflammatory-based diseases involving mast cells. T1AM and TA1 induce, as T3, neuroprotective effects and itch but also hyperalgesia in rodents with a mechanism largely unknown but mediated by the release of histamine. Due to the rapid onset of their effectiveness they may trigger histamine release from a cell where it is "ready-to-be released," i.e., mast cells. Following a very thin path which passes through old experimental and clinical evidence, at the light of novel acquisitions on endogenous T3 metabolites, we aim to stimulate the attention on the possibility that mast cell histamine may be the connector of a novel (neuro) endocrine pathway linking the thyroid with mast cells

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.JRC.G.6-Security technology assessmen

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

N-(3-Ethoxy-phenyl)-4-pyrrolidin-1-yl-3-trifluoromethyl-benzamide (EPPTB) prevents 3-iodothyronamine (T1AM)-induced neuroprotection against kainic acid toxicity

Thyroid hormone and thyroid hormone metabolites, including 3-iodothyronamine (T1AM) and 3-iodothyroacetic acid (TA1), activate AKT signaling in hippocampal neurons affording protection from excitotoxic damage. We aim to explore whether the mechanism of T1AM neuroprotection against kainic acid (KA)-induced excitotoxicity included the activation of the trace amine associated receptor isoform 1 (TAAR1), one of T1AM targets. Rat organotypic hippocampal slices were exposed to vehicle (Veh) or to 5 μM kA for 24 h in the absence or presence of 0.1, 1 and 10 μM T1AM or to 0.1, 1 and 10 μM T1AM and 1 μM N-(3-Ethoxy-phenyl)-4-pyrrolidin-1-yl-3-trifluoromethyl-benzamide (EPPTB), the only available TAAR1 antagonist, or to 1 μM T1AM in the absence or in the presence of 10 μM LY294002, an inhibitor of phosphoinositide 3-kinases (PI3Ks). Cell death was evaluated by measuring propidium iodide (PI) levels of fluorescence 24 h after treatment. In parallel, the expression levels of p-AKT and p-PKA were evaluated by Western blot analysis of slice lysates. The activity of mitochondrial monoamine oxidases (MAO) was assayed fluorimetrically. 24 h exposure of slices to T1AM resulted in the activation of AKT and PKA. KA exposure induced cell death in the CA3 region and significantly reduced p-AKT and p-PKA levels. The presence of 1 and 10 μM T1AM significantly protected neurons from death and conserved both kinase levels with the essential role of AKT in neuroprotection. Furthermore, EPPTB prevented T1AM-induced neuroprotection, activation of PKA and AKT. Of note, in the presence of EPPTB T1AM degradation by MAO was reduced. Our results indicate that the neuroprotection offered by T1AM depends, as for TA1, on AKT activation but do not allow to conclusively indicate TAAR1 as the target implicated. Graphical abstrac

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