A detailed kinetic model for the thermal decomposition of hydroxylamine.

Hydroxylamine may decompose explosively if processed and stored in certain conditions, posing critical safety issues that need to be carefully addressed. A key aspect is related to the characterization of chemical aspects involved in the explosive decomposition of hydroxylamine (HA), requiring accurate and detailed kinetic mechanisms. This work was devoted to the experimental and numerical characterization of the thermal decomposition of aqueous solutions of HA included in the range of 10%w to 50%w. The onset temperatures of thermal decomposition were determined in the range of 143-198 °C under heating rates of 2 and 5 °C min-1, respectively. A reduced mechanism listing 13 species and 11 reactions involving nitrogen-containing species was produced and validated against experimental measurements. Reaction pathways ruling the decomposition of HA were identified. The hydrogen abstraction toward HNOH and H2NO dominates the primary steps of NH2OH decomposition. The generated mechanism was adopted for the definition of a dimensionless stability diagram for the safe use of HA. Finally, results show a self-accelerating behaviour for any temperature larger than 186 °C, defining a monitoring criterion for safe storage of hydroxylamine-solutions.

A perspective on early detection systems models for COVID-19 spreading.

The ongoing COVID-19 epidemic highlights the need for effective tools capable of predicting the onset of infection outbreaks at their early stages. The tracing of confirmed cases and the prediction of the local dynamics of contagion through early indicators are crucial measures to a successful fight against emerging infectious diseases (EID). The proposed framework is model-free and applies Early Warning Detection Systems (EWDS) techniques to detect changes in the territorial spread of infections in the very early stages of onset. This study uses publicly available raw data on the spread of SARS-CoV-2 mainly sourced from the database of the Italian Civil Protection Department. Two distinct EWDS approaches, the Hub-Jones (H&J) and Strozzi-Zaldivar (S&Z), are adapted and applied to the current SARS-CoV-2 outbreak. They promptly generate warning signals and detect the onset of an epidemic at early surveillance stages even if working on the limited daily available, open-source data. Additionally, EWDS S&Z criterion is theoretically validated on the basis of the epidemiological SIR. Discussed EWDS successfully analyze self-accelerating systems, like the SARS-CoV-2 scenario, to precociously identify an epidemic spread through the calculation of onset parameters. This approach can also facilitate early clustering detection, further supporting common fight strategies against the spread of EIDs. Overall, we are presenting an effective tool based on solid scientific and methodological foundations to be used to complement medical actions to contrast the spread of infections such as COVID-19.

Microwave-assisted synthesis of isosorbide-derived diols for the preparation of thermally stable thermoplastic polyurethane.

In order to prepare thermally stable isosorbide-derived thermoplastic polyurethane, the synthesis of two new chiral exo-exo configured diols, prepared from isosorbide, and two types of diphenols (bisphenol A and thiodiphenol) was described. The synthesis conditions were optimized under conventional heating and microwave irradiations. To prove their suitability in polymerization, these monomers were successfully polymerized using 4,4'-diphenylmethane diisocyanate (MDI) and hexamethylene diisocyanate (HDI). Both monomers and polymers have been studied by NMR, FT-IR, TGA, DSC; intrinsic viscosity of polymers has also been determined. The results showed the effectiveness of the synthetic strategy proposed; moreover, a dramatic reduction of the reaction time and an important improvement of the monomers yield using microwave irradiation have been demonstrated. The monomers, as well as the polymers, showed excellent thermal stability both in air and nitrogen. It was also shown that the introduction of sulphur in the polyurethane backbone was effective in delaying the onset of degradation as well as the degradation rate.

Financial austerity measures and their effects as perceived in daily practice by Italian nurses from 2010 to 2011: A longitudinal study.

Abstract Most western economies have in recent years been experiencing one of the longest and deepest economic recessions since the Great Depression. During a recession health-care expenditures are often among the first to be cut. However, what is occurring in daily practice from the point of view of care has not been documented to date. Describing the cost containment interventions undertaken and their effects as perceived in daily practice by Italian nurses was the aim of the study. A longitudinal study design was adopted from 2010 to 2011 involving 1,001 nurses each year. In the 2-year period taken into consideration, participants reported a significant increase in the number of cost containment measures adopted by their health-care organisations. The effects of these cost containment measures have been perceived by nurses especially in terms of (1) increased stress levels, (2) increased number of patients with social problems, and (3) increased nursing workloads. In addition, greater difficulties in finding clinical placement for nursing students and fewer resources devoted to nursing professional development were reported, indicating that some cost containment measures will have long-term effects. The economic crisis seems to affect mainly the most vulnerable groups of society. Innovative solutions for the need to reduce the costs of National Health Services do not seem to emerge from the findings.