Search results for "CATA"
showing 10 items of 13753 documents
Heterogeneous photocatalysis: guidelines on experimental setup, catalyst characterization, interpretation, and assessment of reactivity
2019
Soon after the publication of the first pioneering works on heterogeneous photocatalysis, the number of papers on this topic continuously increased. This intriguing field of research is very complex as it endows with an interdisciplinary overview that involves different aspects of chemistry, physics, material and environmental sciences. Even if photocatalytic applications in real processes are often difficult to be implemented and scaled-up, investigations at laboratory scale are easy to be performed, and in some cases they may give rise to misconceptions. For this reason, the present work aims to sum up most of the common experimental techniques and procedures generally used in heterogeneo…
Test alla tubercolina: proposta di scheda di valutazione del rischio e di interpretazione standardizzata
2004
Relevance of latent infection in the epidemiology of tuberculosis (TB) is expected to increase in many developed countries. Indeed, many demographic, social and public health changes could contribute to the expansion of groups or communities at significantly higher risk than the general population for infection to Mycobacterium tuberculosis or progression from latent to active disease. Tuberculin skin testing (TB), the gold standard for diagnosis of M. tuberculosis infection, is imperfect and prone to false positive and negative results, unless strictly targeted and carefully standardized for reliable performance and interpretation. This paper proposes a pre-test risk assessment questionnai…
La relació entre història de la llengua i història literària
2021
La relació entre la disciplina història de la llengua i la disciplina història de la literatura ha estat una relació de subordinació, tant des del punt vista conceptual com metodològic. La primera ha estat subordinada a la segona. En aquest article tractem en primer lloc de les circumstàncies i els esdeveniments històrics que han determinat aquesta situació de subordinació: la identificació cultural entre llengua i literatura (però amb la supeditació de la primera a la segona), el naixement de la lingüística romànica (que, paradoxalment, no va afavorir l’autonomia de la història de la llengua) i la desclosa de les cultures nacionals, que també van donar prioritat a la literatura nacional. E…
Temporal trends of heavy metals in sediment core from the gulf of Palermo (Sicily, Italy)
2009
The evaluation of long–term heavy metal concentrations in the Gulf of Palermo was carried out in this study. Measurements of Cr, Cu, Hg, Pb and Zn concentrations were performed by atomic absorption spectrophotometry (AAS) on dated fractions of a sediment core, dated by the 210Pbex method. They are found to cover a time period from 1951 to 2004. The constant sedimentation rate model was used for dating. Specific activities of 137Cs have also been measured in the sediment core sections as a check of the time scale derived by the 210Pbex method. A time-series analysis based on temporal decomposition was used in order to investigate the presence of heavy metal pollution trend. The additive comp…
Analisi dei gruppi morfo-funzionali del fitoplancton per la determinazione dello stato ecologico degli ecosistemi acquatici continentali.
2011
Spin Crossover and Long-Lived Excited States in a Reduced Molecular Ruby.
2020
Abstract The chromium(III) complex [CrIII(ddpd)2]3+ (molecular ruby; ddpd=N,N′‐dimethyl‐N,N′‐dipyridine‐2‐yl‐pyridine‐2,6‐diamine) is reduced to the genuine chromium(II) complex [CrII(ddpd)2]2+ with d4 electron configuration. This reduced molecular ruby represents one of the very few chromium(II) complexes showing spin crossover (SCO). The reversible SCO is gradual with T 1/2 around room temperature. The low‐spin and high‐spin chromium(II) isomers exhibit distinct spectroscopic and structural properties (UV/Vis/NIR, IR, EPR spectroscopies, single‐crystal XRD). Excitation of [CrII(ddpd)2]2+ with UV light at 20 and 290 K generates electronically excited states with microsecond lifetimes. This…