Search results for " carbon"

Combined effect of low-molecular-weight organic acids and creosote on phosphatase activities in sandy soil

2018

This paper assesses the impact of creosote and low-molecular-weight organic acids (LMWOAs) on the activity of acid phosphomonoesterase, alkaline phosphomonoesterase, phosphotriesterase, and inorganic pyrophosphatase in soil. The experiment was carried out on loamy sand samples with organic carbon content of 8.71 g · kg -1 , with the following variable factors: dosages of creosote: 0, 0.5%, and 2.5%; type of LMWOAs: oxalic acid, tartaric acid, and citric acid in the amount of 50 mmol · kg -1 of soil; days of experiment: 1, 7, 14, 28, 56, 112. Obtained results showed that contamination with creosote caused decrease in the activity of soil phosphatases. The observed effect did not always incre…

The use of very high resolution images for studying Posidonia oceanica reefs

2020

Posidonia oceanica is an endemic Mediterranean seagrass that forms wide and dense meadows from the surface up to about 40 m depth. This species can develop a biogenic structure called matte, a typical terraced formation built up by itself, consisting of intertwined rhizomes, roots and sediment, which may allow shoots to reach the sea surface forming reefs (récif barrière), considered natural monuments. Posidonia oceanica reefs are particularly exposed to the ongoing increase in temperature and in storm frequency and intensity due to climate change, with negative repercussions on their conservation. Much more attention must be paid to the implementation of monitoring tools able to detect ear…

Variazioni di carbonio organico nei suoli italiani dal 1979 al 2008

2010

I suoli contengono circa tre volte la quantità di carbonio disponibile a livello mondiale nella vegetazione e circa il doppio di quella presente in atmosfera. Tuttavia il carbonio organico del suolo (SOC) si è ridotto in molte aree, mentre è stato rilevato un aumento della CO2 atmosferica. Ricerche recenti hanno dimostrato che sono stati i cambiamenti di uso e gestione del suolo a provocare le maggiori perdite di SOC nel recente passato, piuttosto che le più alte temperature e i cambiamenti delle precipitazioni conseguenti il cambiamento climatico. Lo scopo principale di questo lavoro è quello di stimare le variazioni del contenuto di carbonio organico dei suoli (carbon stock, CS) in Italia…

Pyrolytic formation of polycyclic aromatic hydrocarbons from sesquiterpenes

2012

Author's version of an article in the journal: Food Chemistry. Also available from the publisher at: http://dx.doi.org/10.1016/j.foodchem.2012.06.033 The products of the pyrolysis of four sesquiterpenes, β-caryophyllene, α-cedrene, longifolene and valencene, have been examined. Pyrolysis was carried out at 300, 400 and 500 °C, the products determined by GC–MS and then examined for similarities and differences using multivariate data analysis. Analysis showed that longifolene was most resistant and caryophyllene least resistant to pyrolysis with cedrene and valencene occupying intermediate positions. While the compounds were largely unchanged at 300 °C, polycyclic aromatic hydrocarbons (PAHs…

Amorphous silicon nanotubes

2017

In the following, the attention will be focused on the silicon nanotube (SiNTs) that is a highly desired form of silicon for its fundamental role in the miniaturization trend of the electronic devices. After a description of the properties and applications of SiNTs and their fabrication methods, the attention will be focused on chemical vapour deposition (CVD) template synthesis that is the most usual synthetic method for this material. Then, galvanic template synthesis will be described as a general method for the fabrication of different metals and oxides nanostructures, therefore the use of this technique for synthesizing SiNTs will be detailed. Characterization methods will be also desc…

Study of the Stability of Citrate Capped AgNPs in Several Environmental Water Matrices by Asymmetrical Flow Field Flow Fractionation

2021

Asymmetrical flow field-flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series, was tested for stability studies of dispersions of citrate-capped silver nanoparticles (AgNPs) in several water matrices. The main goal is to provide knowledge to understand their possible behavior in the environment for short times since mixturing (up to 180 min). Ultrapure (UPW), bottled (BW1, BW2), tap (TW), transitional (TrW) and sea water (SW) matrices were assayed. Observations were compatible with the aggregation of AgNPs, a change in the plasmon band and a size growth with time were done. Fractograms showed different evolution fingerprints in the function of the…

Osservazioni fitosociologiche su aspetti di vegetazione a Prunus mahaleb subsp. cupaniana (Rosaceae) dei Monti Madonie (Sicilia)

2010

Zinc Adsorption by Activated Carbon Prepared from Lignocellulosic Waste Biomass

2019

Sawdust was used as a precursor for the production of biomass-based activated carbon. Carbonization and activation are single-stage processes, and steam was used as a physical activation agent at 800 &deg

Influence of Calcium Carbonate Nanoparticles on the Soil Burial Degradation of Polybutyleneadipate-Co-Butylenetherephthalate Films.

2022

A polybutyleneadipate-co-butylenetherephthalate (PBAT) sample, commercially known as Ecoflex®, was processed via melt extrusion with CaCO3 nanoparticles coated with a hydrophobic coating. Blown films of PBAT and two composites with nanofiller (2% and 5%wt) were prepared and degradation tests in soil at 30 °C up to 180 days were carried out with weight loss measurements. Furthermore, biodegradation test according to ISO 14851 was carried out at 30 °C. The effect of CaCO3 on soil burial degradation was assessed by surface wettability and SEM. ATR-FTIR and XPS analyses highlighted chemical modifications induced by soil degradation. CaCO3 nanoparticles decreased surface wettability …

An analysis of carbon storage protected areas with relation to agroforestry management and biodiversity

2008

This work investigated the role of land cover and land use change (LUC) as a soil ability to store carbon and reduce carbon dioxide emission in a Mediterranean area. Using a paired site approach we estimated the effect of land cover change on the carbon stock from 1972 to 2008 in a natural reserve (Grotta di S. Ninfa) in the West of Sicily. Fifteen paired sites representative of five land use change were selected. We studied the effect of land use on soil organic carbon (SOC) content in bulk soil and 2000-1000 µm, 1000-500 µm, 500-250 µm, 250-63 µm, 63-25 µm and <25 µm size fractions. Furthermore, laboratory incubation of the soil samples was conducted to measure carbon dioxide evolution in…