1,720,987 research outputs found
Competitive adsorption of 4-hydroxybenzaldheyde (p-HBA) and toluene (TOL) by Y and ZSM-5 high-silica zeolites
No full textINtech4Water “INtegrated TECHnologies for pollutants in (waste) WATER services"
No full textINTECH4WATER è un progetto che ha come obiettivo la depurazione, la valorizzazione e il riciclo di acque reflue provenienti da depuratori municipali e da processi industriali, in ottica di Circular Economy.
Il progetto prevede una integrazione di tecnologie innovative, sicure e sostenibili, per l’eliminazione dei contaminanti più comuni delle acque reflue (carichi di N e P, inquinanti emergenti, microplastiche, batteri patogeni per l’uomo).
Le tecnologie previste per la sperimentazione sono: filtri ceramici, fotocatalitici e adsorbenti, processi di ossidazione avanzata, UV, ozono e microalghe. Il progetto prevede due fasi: fase 1) di laboratorio, per identificare la migliore combinazione di tecnologie; fase 2) prototipale, per uno scale up delle ricerche e per testare il sistema su scala reale.
Tutti gli step saranno guidati da analisi statistiche avanzate (machine learning e intelligenza artificiale) e corredate da analisi chimiche, biologiche e microbiologiche.
L’idea di creare un nuovo sistema di tecnologie integrate per la depurazione, la valorizzazione e il riciclo di acque reflue di depuratori municipali e processi industriali ha l’obiettivo di migliorare l’efficienza del processo di rimozione degli inquinanti più comuni, chimici e biologici.
Il progetto INTECH4WATER è rivolto specialmente a realtà aziendali con elevata variabilità, nel corso dell’anno, della composizione del refluo, per cui una sola tecnologia di depurazione non può essere in grado soddisfare appieno la depurazione delle acque in uscita dagli impianti.
La possibilità di rendere più efficiente l’intero processo depurativo garantisce una migliore qualità delle acque rilasciate in corpi idrici naturali, con conseguente maggiore tutela della salubrità dell’ambiente e con un’evidente ricaduta positiva sulla salute umana
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Accumulation of trace metals in crayfish tissues: is Procambarus clarkii a vector of pollutants in Po Delta inland waters?
No full textConcentrations of trace elements (Cd, Pb, As, Cu and Zn) were determined in superficial sediments and in hepatopancreas, exoskeleton, and abdominal muscle of the red swamp crayfish Procambarus clarkii from several canals of the Po River Delta area. Sediments of the studied canals exhibited some metal pollution. The hepatopancreas of the crayfish showed a higher concentration of trace metals in comparison to the other tissues at all sites under scrutiny. Concentrations of As and Pb, either in sediment and P. clarkii tissues, were probably related to the use of fertilizers and pesticides. Moreover, the levels of certain metals accumulated in the abdominal muscle (Pb, Cu and Zn) exceeded the threshold values considered harmful to human health. The Toxic Contamination Index, depending on the bioaccumulation data of hepatopancreas and abdominal muscle, allowed us to assess the toxicity by heavy metals of sediments measuring the stress level of the detoxification organ, and resulted in >1 only at two sampling canals. We hypothesize that P. clarkii in the Po River Delta aquatic communities can act as a vector of pollutants, as crayfish can transfer their relatively high amount of heavy metals to higher trophic levels
L−Lysine Amino Acid Adsorption on Zeolite L: a Combined Synchrotron, X-Ray and Neutron Diffraction Study
Full text linkCombined neutron and X-ray powder diffraction techniques highlighted the sorption capacity of the acidic L zeolite towards the L-lysine amino acid. The role of zeolite channels in the stabilization of the lysine absorbed and the effect of water on protein structure are elucidated at atomistic level. The stabilization of the L α-helical conformation is related to strong H-bonds between the tail aminogroups of lysine molecules and the Brønsted acid site as well as to complex intermolecular H-bond system between water molecules, zeolite and amino acid. This finding is relevant in the catalytic synthesis of polypeptide, as well as in industrial biotechnology by qualitatively predicting binding behaviour
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Selective adsorption of toluene and n-hexane binary mixture from aqueous solution on zeolite ZSM-5: Evaluation of competitive behavior between aliphatic and aromatic compounds
No full textIn this study, high silica ZSM-5 was selected as an adsorbent for the removal of toluene (TOL) and n-hexane (HEX) binary mixtures from aqueous solution over a wide range of concentrations. In comparison with the single component systems, the binary mixture induced to a selective adsorption by the ZSM-5 zeolite. As a matter of fact, a selective adsorption, described by a competitive dual site Langmuir adsorption isotherm, is revealed where alkane compound is preferred to the aromatic one. Results from adsorption isotherm were related to the structural answer of the ZSM-5 framework as a function of a HEX-TOL equimolar binary mixture adsorption. Rietveld refinements provided information about the relative position of both molecules within the ZSM-5, and on the intermolecular distances between the adsorption sites of HEX and TOL. Residuals of electron density calculated by mean of delta Fourier maps indicated the presence of both guest molecules but with a clear indication of preferential towards n-hexane, and a clear differential adsorption site distribution. The occurrence of host-guest interactions in the narrow intracrystalline micropores between the solid catalyst and embedded molecules have been revealed
Insights on Ga-zeolite catalysts: X-ray powder diffraction and absorption spectroscopy characterization at ambient conditions
No full textGallium substituted L, mordenite and ferrierite zeolites, obtained through wet impregnation, were characterized combining adsorption isotherms, X-ray powder diffraction (XRPD) and X-ray absorption spectroscopy (XAS) to elucidate nature and structure of the Ga+3 sites of the materials. The saturation capacity of L was higher than those of mordenite and ferrierite. Rietveld refinements on saturated materials confirm the presence of Ga+3 within the zeolites pores system. Besides, the analysis of the structural features (i.e., lightening of tetrahedral bond distances and narrowing of interthetraedral angles) suggest that small fractions of metal cation have been also incorporated in tetrahedral sites. This is corroborated by XAS analysis, which confirms the effective inclusion of gallium into the zeolites frameworks, thus indicating that the incorporation of Ga+3 from wet impregnation within the zeolite structures occurs in both framework and non-framework positions
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