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A theoretical and experimental study on atmospheric pressure microwave plasma-based assembly of free standing graphene sheets is presented. The synthesis method is based on introducing a carbon-containing precursor (C 2 H 5 OH) through a microwave (2.45 GHz) argon plasma environment, where decomposition of ethanol molecules takes place and carbon atoms and molecules are created and then converted into solid carbon nuclei in the 'colder' nucleation zones. A theoretical model previously developed has been further updated and refined to map the particle and thermal fluxes in the plasma reactor. Considering the nucleation process as a delicate interplay between thermodynamic and kinetic factors, the model is based on a set of non-linear differential equations describing plasma thermodynamics and chemical kinetics. The model predictions were validated by experimental results. Optical emission spectroscopy was applied to detect the plasma emission related to carbon species from the 'hot' plasma zone. Raman spectroscopy, scanning electron microscopy (SEM), and x-ray photoelectron spectroscopy (XPS) techniques have been applied to analyze the synthesized nanostructures. The microstructural features of the solid carbon nuclei collected from the colder zones of plasma reactor vary according to their location. A part of the solid carbon was deposited on the discharge tube wall. The solid assembled from the main stream, which was gradually withdrawn from the hot plasma region in the outlet plasma stream directed to a filter, was composed by 'flowing' graphene sheets. The influence of additional hydrogen, Ar flow rate and microwave power on the concentration of obtained stable species and carbon−dicarbon was evaluated. The ratio of sp 3 /sp 2 carbons in graphene sheets is presented. A correlation between changes in C 2 and C number densities and sp 3 /sp 2 ratio was found.

Self-standing graphene sheets were synthesized using microwave plasmas driven by surface waves at 2.45 GHz stimulating frequency and atmospheric pressure. The method is based on injecting ethanol molecules through a microwave argon plasma environment, where decomposition of ethanol molecules takes place. The evolution of the ethanol decomposition was studied in situ by plasma emission spectroscopy. Free gas-phase carbon atoms created in the plasma diffuse into colder zones, both in radial and axial directions, and aggregate into solid carbon nuclei. The main part of the solid carbon is gradually withdrawn from the hot region of the plasma in the outlet plasma stream where nanostructures assemble and grow. Externally forced heating in the assembly zone of the plasma reactor has been applied to engineer the structural qualities of the assembled nanostructures. The synthesized graphene sheets have been analysed by Raman spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy and x-ray photoelectron spectroscopy. The presence of sp 3 carbons is reduced by increasing the gas temperature in the assembly zone of the plasma reactor. As a general trend, the number of mono-layers decreases when the wall temperature increases from 60 to 100 • C. The synthesized graphene sheets are stable and highly ordered.

This study aimed to estimate the prevalence of depression in nursing staff working in Intensive Care Units of hospitals from a city in Northwestern São Paulo State -Brazil, examining its association with participants' socio-demographic characteristics. The Beck Depression Inventory was applied to a sample of 67 nursing workers from three general hospitals, showing an 28.4% prevalence of depression. The analysis based on the multiple model showed a significant association between depression and marital status (OR=1.52), night work (OR=1.46) and double shifts (OR=2.11). Also, there were significant percentages of workers who reported discouragement, sadness and hopelessness. In conclusion, the prevalence of depression is significant and more attention should be paid to this problem workers at these units face. Further studies are needed in the attempt to broaden knowledge on the subject, which can support strategies to guarantee attention to ICU nursing workers' physical and mental health needs. Prevalencia de depresión en trabajadores de enfermería de Unidades de Terapia Intensiva: estudio en hospitales de una ciudad del noroeste del Estado de Sao PauloEste estudio fue realizado con el objetivo de estimar la prevalencia de depresión, en trabajadores de enfermería de Unidades de Terapia Intensiva (UTI) de hospitales de una ciudad del Noroeste del estado de Sao Paulo, analizando su asociación con las características sociodemográficas de los participantes. Se aplicó el Inventario de Depresión de Beck a una muestra de 67 trabajadores de enfermería de tres hospitales generales; se observó una prevalencia de 28,4% de depresión. El análisis por el modelo múltiple demostró asociación significativa entre depresión y estado civil (OR=1,52), trabajo nocturno (OR=1,46) y doble jornada (OR=2,11), fueron significativos también los porcentajes de trabajadores que relataron desanimo, tristeza y desesperanza. Se concluye que es significativa la prevalencia de depresión y que se debe dar mayor atención a ese problema enfrentado por los trabajadores de esas unidades. Se sugiere la realización de otros estudios buscando ampliar el conocimiento sobre la temática, los cuales pueden respaldar estrategias que objetiven asegurar, al trabajador de enfermería de las UTIs, atención a sus necesidades de salud física y psíquica.