Search results for "fluid"

Towards controlling PCDD/F production in a multi-fuel fired BFB boiler using two sulfur addition strategies. Part II: Thermodynamic analysis

2014

Abstract A staged equilibrium process model was developed for a bubbling fluidized bed boiler firing SRF, bark and sludge. The model was used to study the influence of sulfur addition strategies (S-pellet additive and peat co-firing) on the behavior of copper, bromine, and alkalis. Aerosol samples collected from the backpass of the boiler were used to validate the chemistry predicted by the model. The model revealed that Cu existed as Cu 2 S (s3) in the reducing zone, and CuCl (g) (for all test cases) and CuO (s) (during peat co-firing) in the oxidation zones. CuBr 3(g) was also present after the introduction of tertiary air. However the model failed to predict the formation of CuSO 4 , an …

SOURCE RECOGNITION OF INHALED ATMOSPHERIC PARTICLES ACCORDING TO GEOCHEMICAL AND STATISTICAL EVALUATIONS OF TRACE ELEMENT SIGNATURES

2011

During 2001 the Mount Etna had a large eruption producing a large amount of pyroclastic products consisting of a mixture of glass, minerals and soluble salt materials (SAF) encrusting solid particles. Inhalation of the finest of these materials induced pulmonary diseases in people living in subjected areas and gave us the possibility to collect bronchoalveolar lavages (BAL) from people in care in Catania hospitals. Concentrations of several trace elements measured in these BAL fluids (BALF) evidence strong enrichments in several trace elements compared to reference values. Related enrichments factors, calculated with respect to composition of volcanic ejecta (EFASH), show similar values in …

Eosinophil Cationic Protein in Nasal Secretions and Blood Serum in Grass-Pollen Allergic Rhinitis

1996

Concentration of the Eosinophil Cationic Protein (ECP) measured in different body fluids has been demonstrated to be a good marker of eosinophilic inflammation. In allergic asthma, ECP levels in both broncho-alveolar-lavage (BAL) fluid and serum can be used to monitor disease activity. In allergic rhinitis, the value of ECP determinations in serum and nasal secretions was not directly compared, so far. In the present study, ECP levels in blood serum (Se) and nasal secretions (NS) of grass pollen allergic and healthy individuals under pollen exposure were analyzed. Forty-three grass-pollen allergic subjects and 19 healthy volunteers were included. Grass-pollen counts were measured using Bur…

Th17 immunity in children with allergic asthma and rhinitis: a pharmacological approach

2013

Th17 cells and IL-17A play a role in the development and progression of allergic diseases. We analyzed the IL-17A levels in sputum supernatants (Ss), nasal wash (NW) and plasma (P) from Healthy Controls (HC) and children with Asthma/Rhinitis. We tested the expression of IL-17A, RORγ(t) and FOXP3 in peripheral blood T-lymphocytes from intermittent and mild-moderate asthma. The effect of Budesonide and Formoterol was tested "in vitro" on IL-17A, RORγ(t) and FOXP3 expression in cultured T-lymphocytes from mild-moderate asthma/persistent rhinitis patients, and on nasal and bronchial epithelial cells stimulated with NW and Ss from mild-moderate asthma/persistent rhinitis. Further, the effect of …

Influence of the Richardson number on EM force driven flow structures in square-shaped crucible

2014

Abstract This study is devoted to the experimental investigation of the turbulent melt motion in a square crucible where the flow is created by Lorentz forces generated by an external AC magnetic field. As a strong vertical thermal gradient is present in melt during a directional solidification process, a stratification effect takes place and motion in the vertical direction is damped by buoyancy forces. Such a situation arises if density of fluid layers decreases with height. Experimental velocity and temperature measurements are conducted. Transient effects, like collapse of stratification, are observed experimentally. The significance of stratification in the directional solidification m…

Large eddy simulation model for wind-driven sea circulation in coastal areas

2013

Abstract. In the present paper a state-of-the-art large eddy simulation model (LES-COAST), suited for the analysis of water circulation and mixing in closed or semi-closed areas, is presented and applied to the study of the hydrodynamic characteristics of the Muggia bay, the industrial harbor of the city of Trieste, Italy. The model solves the non-hydrostatic, unsteady Navier–Stokes equations, under the Boussinesq approximation for temperature and salinity buoyancy effects, using a novel, two-eddy viscosity Smagorinsky model for the closure of the subgrid-scale momentum fluxes. The model employs: a simple and effective technique to take into account wind-stress inhomogeneity related to the …

Determination of bupivacaine in human plasma by high-performance liquid chromatography.

1984

Environment, wealth, inequality and the burden of disease in the Accra metropolitan area, Ghana

2005

The study examines environmental problems and adverse impacts on the health of urban households in the Accra metropolitan area, Ghana. Accra is faced with severe inadequacy of urban infrastructure in the face of rapid population growth in the metropolis. More than half of the city's population do not have access to solid waste collection services. Only 39.8% of households have indoor pipe and over 35.0% of households depend on unsanitary public latrines whilst 2.5% do not have access to toilet facilities. Human excrement, garbage and wastewater are usually deposited in surface drains, open spaces and streams in poor neighbourhoods. The resultant poor sanitation has serious health impacts as…

2021

The increasing digitalization of economies has highlighted the importance of digital transformation and how it can help businesses stay competitive in the market. However, disruptive changes not only occur at the company level; they also have environmental, societal, and institutional implications. This is the reason why during the past two decades the research on digital transformation has received growing attention, with a wide range of topics investigated in the literature. The following aims to provide insight regarding the current state of the literature on digital transformation (DT) by conducting a systematic literature review. An analysis of co-occurrence using the software VOSviewe…

Theoretical study of a Bénard Marangoni problem

2011

[EN] In this paper we prove the existence of strong solutions for the stationary Benard-Marangoni problem in a finite domain flat on the top, bifurcating from the basic heat conductive state. The Benard-Marangoni problem is a physical phenomenon of thermal convection in which the effects of buoyancy and surface tension are taken into account. This problem is modelled with a system of partial differential equations of the type Navier-Stokes and heat equation. The boundary conditions include crossed boundary conditions involving tangential derivatives of the temperature and normal derivatives of the velocity field. To define tangential derivatives at the boundary, intended in the trace sense,…