Search results for " elements"

Volcanic signature of volatile trace elements on atmospheric deposition at Mt. Etna, Italy

2009

Volcanic volatiles and aerosol emitted into the atmosphere ultimately fall on the Earth’s surface as wet or dry deposition, and they can influence the environment and the ecosystems at local and regional scales. Therefore, atmospheric deposition plays a key-role in the geochemical cycles, redistributing volcanogenic elements to the ground. For this reason, estimating the volcanogenic trace element fluxes from the atmosphere to the surface is necessary for a better knowledge of the environmental impact of the volcanic emissions. Nevertheless, from a literature review, we have recognized the scarcity of investigation on trace element deposition in the surroundings of active volcanoes. Here, w…

Impact of Volcanic Emissions on Trace Elements Contents Measured in Endemic Plants at Mt. Etna (Italy)

2011

Effects of Dissolved Complexation on REE Fate During Interactions between Volcanic Ash and Coexisting Fluids

2013

AbstractThis work analyzes REE behavior during the delivery of volcanic ash into a marine system and highlights the effects induced by dissolved carbonate and humate complexes on REE release. Kinetic experiments were carried out during a 6-month period using a batch method approach. Results show that the highest degree of REE leaching occurs during the early stage. Altered phases that crystallize induce REE sorption and dissolved complexation towards surface complexation, concurrent processes that are enhanced by Y/Ho, La/Yb, and Ce/Ce* changes, whereas dissolved humates and carbonates influence the dissolution rate of ash and the dissolved REE behavior.

The Cycle of volcanogenic trace elements at Mt Etna (Italy): From volcanic emissions to atmospheric deposition

2009

Recognition of water masses according to geochemical signatures in the Central Mediterranean sea: Y/Ho ratio and rare earth element behaviour

2007

This study reports the results of geochemical investigations carried out in the Strait of Sicily (Central Mediterranean Sea) during the oceanographic cruise BANSIC 2000, focusing on the area around the Pantelleria Island. We evaluate the interface processes between dissolved phase and suspended particulate matter in the water columns on the basis of Y/Ho ratio and rare earth elements and yttrium distributions that are suitable to trace the occurrence of different water layers in Central Mediterranean Area. The main source of trace elements to the sea water system was recognized in the atmospheric fallout, while different scavenging mechanisms among Y and rare earth elements occur. Cation ex…

Distribution patterns of particulate trace metals in the water column and nepheloid layer of the Gulf of Riga.

2004

The dynamics (fate) of trace metals in suspended particulate matter within the Gulf of Riga has not yet been adequately addressed in the scientific literature. Therefore, during a two year period (2001-2002) samples of suspended particulate matter and surface sediments for trace metal analysis were collected in the Gulf of Riga and the Daugava river, and these data were combined with background information from the national marine monitoring program in Latvia. This paper presents a descriptive study of solid phase trace metals (aluminium, iron, cadmium, chromium, copper, manganese, nickel, lead and zinc) dynamics and their spatial distribution within the Gulf of Riga based on Principal Comp…

Costruire con l’acqua: nuovi paradigmi dell’architettura sostenibile Building with water: new standards of sustainable architecture

2017

All’interno di una prassi architettonica sempre più consolidata che mira alla sostenibilità ambientale e all’autosufficienza energetica, l’articolo riporta ricerche e sperimentazioni condotte in ambito internazionale sul tema acqua-architettura, evidenziando come, partendo dall’ottima capacità del fluido di termoregolare gli ambienti confinati, si possa arrivare a considerare l’acqua anche un materiale componente dell’architettura. Within an increasingly consolidated architectural practice aiming at environmental sustainability and energy self-sufficiency, the article reports international research and experiments carried out on water-architecture. Furthermore, it highlights how, starting f…

MODELLING OF WATER-ROCK INTERACTIONS IN CARBONATE AQUIFERS: INSIGHTS FROM A CASE STUDY IN THE MADONIE AREA (SICILY)

2009

Searching the most appropriate sample pretreatment for the elemental analysis of wines by inductively coupled plasma-based techniques.

2008

Different sample preparation methods were evaluated for the simultaneous multielement analysis of wine samples by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). Microwave-assisted digestion in closed vessel, thermal digestion in open reactor, and direct sample dilution were considered for the determination of Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Y, Mo, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Tl, Pb, and Bi in 12 samples of red wine from Valencia and Utiel-Requena protected designation of origin. ICP-MS allows the determination of 17 elements in most…

Assessment of Modelling in Mathematics Examination Papers: Ready-Made Models and Reproductive Mathematising

2013

In the Netherlands modelling is integrated into the mathematics curriculum. This chapter describes a study of modelling characteristics in recent mathematics examination papers. Results show that the tasks convey the message that mathematics can be found in unexpected situations. In many tasks a situation and a ready-made model are given and students are asked to work with the model. For mathematising, two design principles were: to finalise the parameters of a given model, and to reconstruct a given mathematical model from verbal descriptions and diagrams of a situation. These formats were coined as mechanistic and reproductive mathematising respectively. These formats have been introduced…