1,721,040 research outputs found
A simple, reproducible and accurate lung ultrasound technique for COVID-19: when less is more
No full textSonographic signs and patterns of COVID-19 pneumonia
No full textThe pandemic of COVID-19 is seriously challenging the medical organization in many parts of the world. This novel corona virus SARS-CoV-2 has a specific tropism for the low respiratory airways, but causes severe pneumonia in a low percentage of patients. However, the rapid spread of the infection during this pandemic is causing the need to hospitalize a high number of patients. Pneumonia in COVID-19 has peculiar features and can be studied by lung ultrasound in the early approach to suspected patients. The sonographic signs are non-specific when considered alone, but observation of some aspects of vertical artifacts can enhance the diagnostic power of the ultrasound examination. Also, the combination of sonographic signs in patterns and their correlation with blood exams in different phenotypes of the disease may allow for a reliable characterization and be of help in triaging and admitting patients
Considerazioni relative alla protezione ambientale da immissione di polveri da cementifici
No full textHow i do it: Lung ultrasound
Full text linkIn the last 15 years, a new imaging application of sonography has emerged in the clinical arena: lung ultrasound (LUS). From its traditional assessment of pleural effusions and masses, LUS has moved towards the revolutionary approach of imaging the pulmonary parenchyma, mainly as a point-of-care technique. Although limited by the presence of air, LUS has proved to be useful in the evaluation of many different acute and chronic conditions, from cardiogenic pulmonary edema to acute lung injury, from pneumothorax to pneumonia, from interstitial lung disease to pulmonary infarctions and contusions. It is especially valuable since it is a relatively easy-to-learn application of ultrasound, less technically demanding than other sonographic examinations. It is quick to perform, portable, repeatable, non-ionizing, independent from specific acoustic windows, and therefore suitable for a meaningful evaluation in many different settings, both inpatient and outpatient, in both acute and chronic conditions.In the next few years, point-of-care LUS is likely to become increasingly important in many different clinical settings, from the emergency department to the intensive care unit, from cardiology to pulmonology and nephrology wards. © 2014 Gargani and Volpicelli; licensee BioMed Central Ltd
Performance of small scale fixed bed reactors for limestone neutralization of acid waters
No full text"Kinetics of adsorption of mercuric chloride vapors on sulfur impregnated activated carbon"
No full textInjection of activated carbon impregnated with sulfur or iodine compounds into the flue gases is a promising technique to control mercuric chloride emissions from the combustion of municipal solid wastes. In the present paper the attention is focused on the adsorption of HgCl2 on activated carbon and on the same carbon impregnated with Na2S. The study was performed at laboratory scale, varying the HgCl2 concentration in the inlet stream to the bed in the range of 1-4 mg/m3 and keeping the bed temperature at 150°C. Three different adsorbents were used, i.e. raw commercially available activated carbon and two impregnated activated carbons (7.8% w/w and 18.7% w/w of Na2S). The experimental runs led to the determination of the breakthrough curves for the fixed bed and of the adsorption isotherms for the three materials at 150°C. The results showed that, while "raw" activated carbon is capable of removing mercuric compounds, the impregnation process definitely enhances its adsorption capacity, probably due to a stronger interaction between sulfur and mercury. The adsorption isotherms, which have a characteristic "Langmuir" shape, were used to evaluate the Langmuir parameters for the three different materials under investigation. Eventually the Langmuir parameters were used to solve the adsorption equations for the bed, leading to the individuation of the kinetic constants of the process
"SO2 absorption in a bubbling reactor using limestone suspensions"
No full textIn the present work attention was focused on a wet flue gas desulfurization process using limestone suspensions, which is the most common method used to reduce SO2 emissions from power plant exhaust gases. The SO2 absorption rate was measured varying both the SO2 concentration in the gas phase and the limestone concentration in the suspension. The experiments were performed by bubbling mixtures of sulfur dioxide and nitrogen in the continuous limestone aqueous suspension. The absorption phenomenon was studied by making use of the film theory to describe the liquid-side mass transfer. It was assumed that the liquid-phase diffusional resistance is concentrated in a layer the thickness of which depends on fluid dynamics, but which is independent of the nature of the reactions taking place. The equations considered by the model describe conditions of thermodynamic equilibrium as well as material and electrical balances. Furthermore, they take into account the effect of the gradient of the electric potential of diffusion on the diffusive transport of ions and molecules in the film surrounding the gas-liquid interface. The SO2 absorption rate and the limestone dissolution rate experimentally determined were used to integrate the model equations, yielding the value of the film thickness, and allowing the determination of the concentration profiles of the different species in the liquid film and of the enhancement factor for chemical absorption. Consistency between model and experimental results, on the basis of the hypothesis of the model, was found
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