Search results for "Ground"

Mobility and fluxes of major, minor and trace metals during basalt weathering and groundwater transport at Mt. Etna volcano (Sicily)

2000

Abstract The concentrations and fluxes of major, minor and trace metals were determined in 53 samples of groundwaters from around Mt Etna, in order to evaluate the conditions and extent of alkali basalt weathering by waters enriched in magma-derived CO 2 and the contribution of aqueous transport to the overall metal discharge of the volcano. We show that gaseous input of magmatic volatile metals into the Etnean aquifer is small or negligible, being limited by cooling of the rising fluids. Basalt leaching by weakly acidic, CO 2 -charged water is the overwhelming source of metals and appears to be more extensive in two sectors of the S-SW (Paterno) and E (Zafferana) volcano flanks, where out …

Raw material variability as archaeological tools: Preliminary results from a geochemical study of the basalt vessel workshop at Iron Age Tel Hazor, I…

2016

The discovery of a basalt vessel workshop at Tel Hazor, one of the most important Iron Age sites in the Near East, marks a turning point in our understanding of stone artifact production and distribution during the1st millennium BCE. It offers a rare opportunity to characterize ancient raw material sources, production sites, and study production, trade and distribution systems. The basalt vessel workshop, the only one of its kind in the Levant, produced large quantities of bowl preforms and production waste. To better understand the production and distribution systems behind this specialized production center, in 2011 we initiated a focused geochemical project that concentrated on the produ…

Archaeological excavation confirms the geophysical anomalies recorded at the cathedral of tarragona - A comparative study

2011

An integrated geophysical survey was conducted in September 2007 at the Cathedral of Tarragona to search for archaeological remains of the Roman temple dedicated to the Emperor Augustus. Many hypotheses about its location have been put forward, the most recent ones suggesting it could be inside the present cathedral. A project including Electrical resistivity tomography (ERT) and Ground probing radar (GPR) was planned for a year and conducted during a week of intensive field survey. Both ERT and GPR provided detailed information about subsoil structures. Different ERT techniques and arrays were used, ranging from standard Wenner-Schlumberger 2D sections to full 3D electrical imaging using t…

Recharge stations: A review

2016

Charging equipment for all-Electric Vehicles (EVs) is classified by the rate at which the batteries are charged. Charging times vary based on how depleted the battery is, how much energy it holds, the type of battery, and the type of Electric Vehicle Supply Equipment (EVSE). In this paper, a review of the innovative charging stations is reported.

Realtà e fondamento. Su un certo modo dell’esistenza

2021

By asking the reason for the existence of something rather than nothing, the question of ground implies another question, which asks what is meant by existence. Depending on the criterion of existence and, hence, on the following ontological commitment, the question of ground can assume different ontological weights and may even appear senseless. Further, the question of sufficient reason refers to the causal power of the form, which marks the original questioning of metaphysics.

The coffee-house: Upcycling spent coffee grounds for the production of green geopolymeric architectural energy-saving products

2023

This study investigates a possible alternative reuse of spent coffee grounds (SCG), the major residue of the brewing process, to manufacture green geopolymeric materials for innovative building applications in energy-saving construction, in line with the European Green Deal towards zero-energy building. Specimens were prepared by a combination of biomass fly ash from the Kraft paper-pulp process, as raw material (70 wt%), and SCG (up to 17.5 %), as filler. The high amount of reused bio-wastes makes the material fit the requirements for the Minimum Environmental Criteria (MEC) certification, in light of the Circular Economy (CE) approach. Sustainability is also boosted by the manufacturing p…

Hydrogeological Behaviour and Geochemical Features of Waters in Evaporite-Bearing Low-Permeability Successions: A Case Study in Southern Sicily, Italy

2020

Knowledge about the hydrogeological behaviour of heterogeneous low-permeability media is an important tool when designing anthropogenic works (e.g., landfills) that could potentially have negative impacts on the environment and on people&rsquo

Insects and fungi: ecological interactions and functional biodiversity

Batch Test Evaluation of Four Organic Substrates Suitable for Biological Groundwater Denitrification

2014

Nitrates pollution represents nowadays a serious issue related to the quality of groundwater; continuous growth of industrial-scale agricultures lead to an increase of nitrates content in groundwater in the last years. Several technologies have been validated as capable to promote in situ biological nitrates remediation, such as permeable reactive barriers (PRB), biotrench, biobarriers etc. These technologies are all characterised by the use of organic substrate that act as a slow release carbon source. In free dissolved oxygen absence, such organic carbon is further oxidised, by heterotrophic bacteria naturally present in soil, in compliance to anoxic metabolism by using nitrates bound oxy…

Quantum chemical modelling of electron polarons and excitons in ABO3perovskites

2000

Quantum chemical calculations using the intermediate neglect of the differential overlap (INDO) method, combined with the large unit cell periodic model argue for an existence of the self-trapped electrons in KNbO3 and KTaO3 perovskite crystals. An electron in the ground state occupies predominantly t2g orbital of a Nb4+ ion. Its orbital degeneracy is lifted by a combination of the breathing and Jahn-Teller modes where four nearest equatorial O atoms are displaced outwards and two oxygens shift inwards along the z axis. Triplet exciton is shown to be in a good approximation of a pair of nearest Jahn-Teller electron and hole polarons (a bipolaron) which is very likely responsible for the `gr…