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In this work, the capability of two commercial high silica zeolites (HSZs), namely ZSM-5 and Y, for the removal of chlorobenzene (CB) from water was investigated by combining chromatographic and diffractometric techniques. The adsorption isotherms and kinetics of CB on ZSM-5 and Y zeolites were determined from batch tests. The adsorption kinetics were very fast; the time to reach equilibrium was less than 10 min. The equilibrium data of CB on the two HSZs showed dissimilarities that are particularly evident in the adsorption data concerning the low concentration range, where Y zeolite is characterized by low adsorption. On the contrary, at higher solution concentrations the adsorption capacity of Y is higher than that of ZSM-5. The crystalline structures of Y and ZSM-5 saturated with CB were investigated by X-ray diffraction (XRD) techniques. Rietveld refinement analyses of XRD data allowed for quantitative probing of the structural modifications of both zeolites after CB adsorption and provided insight into the preferred zeolite adsorption sites in both microporous materials. The refined framework-extraframework bond distances confirm that interactions between the selected organic contaminant and hydrophobic zeolites are mediated via co-adsorbed H2O. The occurrence of H2O -CB-framework oxygen oligomers explains variations in both the unit cell parameters and the shape of the channels, clearly confirming that water plays a very relevant role in controlling the diffusion and adsorption processes in hydrophobic zeolites. [ABSTRACT FROM AUTHOR]

Purpose: During economic recession people with mental health problems have higher risk of losing their job. This paper analyses the issue by considering the Italian rates of unemployment amongst individuals with and without mental health problems in 2005 and 2013, that is prior and during the economic crisis. Methods: We used data from the National surveys on “Health conditions and use of health services” carried out by the Italian National Institute of Statistics (ISTAT) for the years 2005 and 2013. The surveys collected information on the health status and socioeconomic conditions of the Italian population. Self-reported unemployment status was analysed amongst individuals with and without reported mental health problems. In addition, descriptive statistics were performed in order to detect possible differences in the risk of unemployment within different regional contexts characterised by different socio-economic conditions. Results: The recession determined increased disparities in unemployment rates between people with and without mental health problems. Regardless to the presence of mental health problems, young people were more likely to be unemployed. Among people who reported mental health problems, males were more likely to be unemployed than females. People with low education level were more likely to be unemployed, particularly during the recession and in presence of mental health problems. Changes in unemployment rates due to the crisis showed different patterns across different regions of the Country. Conclusions: These analyses confirm that in periods of economic crisis people with mental health problems are at risk of experiencing exclusion from labour market. In addition, the impact is even worse within the group with low education and younger age. These findings emphasise the importance of specific interventions aimed at promoting labour market participation and reintegration for people with mental health problems. [ABSTRACT FROM AUTHOR]

The temperature-induced desorption of methyl tert-butyl ether (MTBE) from aqueous solutions onto hydrophobic ZSM-5 was studied by in situ synchrotron powder diffraction and chromatographic techniques. This kind of information is crucial for designing and optimizing the regeneration treatment of such zeolite. The evolution of the structural features monitored by full profile Rietveld refinements revealed that a monoclinic (P21/n) to orthorhombic (Pnma) phase transition occurred at about 100 °C. The MTBE desorption process caused a remarkable change in the unit-cell parameters. Complete MTBE desorption was achieved upon heating at about 250 °C. Rietveld analysis demonstrated that the desorption process occurred without any significant zeolite crystallinity loss, but with slight deformations in the channel apertures. [ABSTRACT FROM AUTHOR]

The adsorption of toluene from aqueous solutions onto hydrophobic zeolites was studied by combining chromatographic, thermal and structural techniques. Three beta zeolites (notated BEAs, since they belong to BEA framework type), with different SiO2/Al2O3 ratios (i.e., 25, 38 and 360), before and after calcination, were tested as adsorbents of toluene from aqueous media. This was performed by measuring the adsorbed quantities of toluene onto zeolites in a wide concentration range of solute. The adsorption data were fitted with isotherms whose models are based on surface heterogeneity of the adsorbent, according to the defective structure of beta zeolites. The thermal treatment considerably increases the adsorption of toluene, in the low concentration range, on all BEAs, probably due to surface and structural modifications induced by calcination. Among the calcined BEAs, the most hydrophobic zeolite (i.e., that with SiO2/Al2O3 ratio of 360) showed the highest binding constant, probably due to its high affinity for an organophilic solute such as toluene. The high sorption capacity was confirmed by thermogravimetric analyses on BEAs, before and after saturation with toluene. [ABSTRACT FROM AUTHOR]

Oxidative potential (OP) of particulate matter (PM) − defined as the capacity of PM to oxidize target molecules generating reactive oxygen species (ROS) − has been proposed as a more health relevant metric than PM mass. In this study two cell-free methods were used to assess the OP of PM filters collected at an urban site and to evaluate correlation with PM mass and PM composition. Among the different assays existing, two inexpensive and user-friendly methods were used both based on spectrophotometric measurements of depletion rate of target reagents oxidized by redox-active species present in PM. One assay measures the consumption of dithiothreitol (OP DTT ) and the other the ascorbate (OP AA ). Although both assays respond to the same redox-active species, i.e., quinones and transition metals, no correlations were found between OP DTT and OP AA responses to compounds standard solutions as well as to ambient samples. When expressed in relation to air volume, OP DTT m −3 strongly correlates with PM 2.5 mass whereas no correlation was found for OP AA m −3 with PM 2.5. When expressed on mass basis, both OP DTT μg −1 and OP AA μg −1 show a strong dependence on the sample composition, with higher OP for summer samples. OP DTT m −3 were highly correlated with the determined metals (Cu, Zn, Cr, Fe, Ni, Mn) whereas OP AA m −3 showed only moderate correlation with Cu and Mn. Thus, the two assays could potentially provide complementary information on oxidative potential characteristic of PM. Consequently, the combination of the two approaches can strengthen each other in giving insight into the contribution of chemical composition to oxidative properties of PM, which can subsequently be used to study health effects. [ABSTRACT FROM AUTHOR]

Background: The Great Recession has caused worldwide tangible costs in terms of cuts in employment and income, which have been widely recognised also as major social determinants of mental health. Italy has not been spared from the financial crisis with severe societal and mental health consequences. In addition, a strong earthquake hit the province of Modena, Italy, in 2012, that is, amid the crisis. Aims: In this study, we explored and investigated the possible additional impact of concurrent events such as economic crisis and a natural disaster. Methods: Our analysis elaborated data from two local surveys, ICESmo2 (2006) and ICESmo3 (2012), and a national survey carried out in 2013 by the Italian National Institute of Statistics (Istituto Nazionale di Statistica (ISTAT)). A regression model was adopted to distinguish the effect of the crisis and the earthquake. Results: Our analysis confirmed the negative effect of the economic crisis on psychological wellbeing, but within the province of Modena such an effect resulted as even stronger compared with the rest of Italy, particularly within those areas struck by the earthquake. Conclusion: Being hit by a combination of two major negative events might have a significantly increased negative effect on psychological health. The higher repercussion observed is not only attributable to the occurrence of a natural disaster but can be reasonably related to the additional effect of unemployment on psychological dimensions. [ABSTRACT FROM AUTHOR]

The adsorption behaviour of three commonly used drugs, namely ketoprofen, hydrochlorothiazide and atenolol, from diluted aqueous solutions on beta zeolites with different Si O2/ Al2 O3 ratio (i.e. 25, 38 and 360) was investigated by changing the ionic strength and the pH, before and after thermal treatment of the adsorbents. The selective adsorption of drugs was confirmed by thermogravimetry and X-ray diffraction. The adsorption capacity of beta zeolites was strongly dependent on both the solution pH and the alumina content of the adsorbent. Such a remarkable difference was interpreted as a function of the interactions between drug molecules and zeolite surface functional groups. Atenolol was readily adsorbed on the less hydrophobic zeolite, under pH conditions in which electrostatic interactions were predominant. On the other hand, ketoprofen adsorption was mainly driven by hydrophobic interactions. For undissociated molecules the adsorption capability increased with the increase of hydrophobicity. [ABSTRACT FROM AUTHOR]

The current study was designed to demonstrate the efficiency of selected zeolites in the immobilization of heavy metals and volatile organic compounds from water in the industrial area of Tito Scalo (Basilicata Region in Southern Italy). The efficiency of zeolite materials has been evaluated by analyzing real water samples, by a multi-technique approach. Gas chromatography (GC) and inductively coupled plasma optical emission spectrometry (ICP-OES) were selected for the detection of volatile organic compounds (VOCs) and heavy metals respectively, and then by thermal analysis (TG, DTA) and X-ray powder diffraction (XRD) to verify the presence of contaminants in the structural channels of the adsorbents. ZSM-5 zeolite (MFI topology) was suitable for volatile organic compounds, showing removal efficiencies 87%. 13X (FAU topology) was more selective for in situ abatements of heavy metals, with efficiencies up to 100%. After VOCs and heavy metals removal, structure refinements of loaded zeolites highlighted variations of both lattice parameters and extraframework content confirming the pollutants immobilization in the framework microporosities. The occurrence of these species was also confirmed by DTA curves showing different phenomena explained on the basis of the nature and number of extraframework species hosted in the zeolite micropores. [ABSTRACT FROM AUTHOR]

• Caffeic Acid adsorption onto ZSM-5 depends on pH. • Caffeic Acid is incorporated into the zeolite framework. • The hydroxyl group of caffeic acid interacts with the framework oxygen atoms. • Competitive adsorption on ZSM-5 follows the order Toluene > Caffeic Acid. Wastewaters and polluted natural water can contain a large variety of organic substances deriving from both natural and anthropogenic sources. Hydrophobic zeolites have great potential for the removal of different organic substances and among them aromatic, chlorinated, and oxygenated compounds. In this work the influence of caffeic acid - an allelochemical representing low molecular weight natural organic matter - on the adsorption of toluene in aqueous matrix has been investigated. To accomplish this task, the adsorption of caffeic acid on ZSM-5 has been studied. Differently from toluene, whose adsorption is not significantly influenced by pH, the uptake of caffeic acid onto zeolite strongly depends on pH, the maximum saturation capacity (46 mg g−1) was obtained at pH 4, corresponding to the nonionized form of caffeic acids. Additionally, caffeic acid interacts with zeolite framework and water molecule as suggested from the shift in the apparent dissociation constant evaluated from adsorption data and confirmed by structural investigation. Competitive adsorption of binary mixture of toluene and caffeic acid in a wide concentration range shows that ZSM-5 is a selective adsorbent for Toluene, and when caffeic acid is present at high concentration (100 mg L−1) the adsorbed quantity of toluene from solution is reduced of less than 15 %. [ABSTRACT FROM AUTHOR]

The present work focused on the use of high-silica commercial zeolites as sorbent media for pharmaceuticals in an aqueous matrix. As drug probes, ketoprofen, hydrochlorothiazide, and atenolol were selected, because of their occurrence in surface waters and effluents from wastewater treatment plants. Pharmaceuticals adsorption was evaluated for two Faujasite topology zeolites with Silica/Alumina Ratio 30 and 200. The selected zeolites were demonstrated to be efficient sorbents towards all investigated pharmaceuticals, thanks to their high saturation capacities (from 12 to 32% w/w) and binding constants. These results were corroborated by thermal and structural analyses, which revealed that adsorption occurred inside zeolite's porosities, causing lattice modifications. Finally, zeolites have been tested as a pre-concentration media in the dispersive-solid phase extraction procedure. Recoveries higher than 95% were gained for ketoprofen and hydrochlorothiazide and approximately 85% for atenolol, at conditions that promoted the dissolution of the neutral solute into a phase mainly organic. The results were obtained by using a short contact time (5 min) and reduced volume of extraction (500 µL), without halogenated solvents. These appealing features make the proposed procedure a cost and time saving method for sample enrichment as well as for the regeneration of exhausted sorbent, rather than the more energetically expensive thermal treatment. [ABSTRACT FROM AUTHOR]