Search results for "Biomas"

Context-sensitive framework for visual analytics in energy production from biomass

2014

Data masses require a lot of data processing. Data mining is the traditional way to convert data into knowledge. In visual analytics, humans are integrated into the process as there is continuous interaction between the analyst and the analysis software. Data mining methods can be utilized also in visual analytics where the priority is given to the visualization of the information and to dimension reduction. However, the provided data is not always enough. There is a large amount of background contextual information, which should be included into the automated process. This paper describes a context-sensitive approach, in which we utilize visual analytics by studying all phases in the proce…

I galligeni dell'Eucalitto da biomassa: dannosità e prospettive di controllo biologico.

2007

Modeling the influence of potassium content and heating rate on biomass pyrolysis

2017

This study presents a combined kinetic and particle model that describes the effect of potassium and heating rate during the fast pyrolysis of woody and herbaceous biomass. The model calculates the mass loss rate, over a wide range of operating conditions relevant to suspension firing. The shrinking particle model considers internal and external heat transfer limitations and incorporates catalytic effects of potassium on the product yields. Modeling parameters were tuned with experimentally determined char yields at high heating rates (>200 K s−1) using a wire mesh reactor, a single particle burner, and a drop tube reactor. The experimental data demonstrated that heating rate and potassium …

Valorization potential of technical lignins from Norway spruce (Picea abies) via pyrolysis

2022

Analytical pyrolysis (Py-GC/MS) on mg-scale of Norway spruce (Picea abies)-derived kraft lignin, ethanosolv lignin, and dried lignin-rich soda-anthraquinone (AQ) black liquors was studied at 500 °C to compare the valorization potential of these materials, focusing on the type and yield of condensable pyrolysis products. Of particular interest was the relatively selective formation of guaiacol (2-methoxyphenol) from the dried soda-AQ black liquors in contrast to the formation of complex phenolic product mixtures from the pyrolysis of the kraft and ethanosolv lignins. It was shown that this finding could be attributed to differences in composition and structure as was assessed by various NMR …

Assessment of cross-flow filtration as microalgae harvesting technique prior to anaerobic digestion: Evaluation of biomass integrity and energy demand

2018

[EN] In the present study, the effect of cross-flow filtration (CFF) on the overall valorization of Chlorella spp. microalgae as biogas was assessed. The effect of CFF on microalgae cell integrity was quantified in terms of viability which was correlated with the anaerobic biodegradability. The viability dropped as the biomass concentration increased, whereas anaerobic biodegradability increased linearly with the viability reduction. It was hypothesized that a stress-induced release and further accumulation of organic polymers during CFF increased the flux resistance which promoted harsher shear-stress conditions. Furthermore, the volume reduction as the concentration increased entailed an …

Biomass Assessment of Agricultural Crops Using Multi-temporal Dual-Polarimetric TerraSAR-X Data

2019

The biomass of three agricultural crops, winter wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and canola (Brassica napus L.), was studied using multi-temporal dual-polarimetric TerraSAR-X data. The radar backscattering coefficient sigma nought of the two polarization channels HH and VV was extracted from the satellite images. Subsequently, combinations of HH and VV polarizations were calculated (e.g. HH/VV, HH + VV, HH × VV) to establish relationships between SAR data and the fresh and dry biomass of each crop type using multiple stepwise regression. Additionally, the semi-empirical water cloud model (WCM) was used to account for the effect of crop biomass on radar backscatter …

Agronomical and chemical characterisation of Thymbra capitata (L.) Cav. biotypes from Sicily, Italy

2015

In this study the agromomical and chemical characterization of 13 sicilian biotypes of Thymbra capitata (L.) Cav. (or Thymus capitatus Hoff. et Link.) collected from different areas of Sicily (Italy) and grown under the same agricultural and environmental condition are reported. The main morpho-productive parameters and quali-quantitative profile of essential oils were determined . Essential oils were extracts from the aerial parts of the plants by hydrodistillation. The essential oils were analyzed by GC-FID and GC-MS. Hierarchical Cluster Analysis and Principal Component Analysis statistical methods were used to group biotypes according to the essential oils chemical composition. The esse…

Monitoring deforestation and forest degradation linking high-resolution satellite data and field data in the context of REDD+. A case of Tanzania

2017

El principal objetivo de este doctorado es apoyar el desarrollo de un sistema nacional de monitoreo forestal en Tanzania para informar sobre las emisiones actuales e históricas derivadas de la deforestación y la degradación forestal. El marco de la tesis se centra específicamente en el emergente contexto internacional de la iniciativa REDD + (Reducción de Emisiones por Deforestación y Degradación) de las Naciones Unidas, bajo la cual los países pueden obtener subsidios financieros para demostrar que están reduciendo sus emisiones de carbono de tierras forestales con respecto a su práctica histórica reciente. La investigación se centró en cinco áreas de investigación: La parte (1) revisa los…

Sulla (Hedysarum coronarium L.) leaves and stems as a potential biofuel feedstock

2014

Sulla (Hedysarum coronarium L. syn., Sulla coronaria [L.] Medik.) is a short-lived perennial legume native to the Mediterranean basin, where it is extensively grown as a 2-year forage crop playing a key role in cereal-based systems of semi-arid regions thanks to its versatility, (e.g., used for grazing, hay and silage production, and grazing associated with hay production), good-quality forage, and environmental benefits. To date, sulla has not been considered as a bioenergy crop. This research aimed to evaluate the potential of sulla biomass as a biofuel feedstock; in addition, due to the possibility to separate the leaves from the stems as suggested for alfalfa, the biomass composition wa…

Electric Field Impact On The Biomass Gasification And Combustion Dynamics

2015

Experimental investigations of the DC electric field effect on thermal decomposition of biomass, formation of the axial flow of volatiles (CO, H2, CxHy), mixing of volatiles with swirling airflow at low swirl intensity (S ≈ 0.2-0.35), their ignition and on formation of combustion dynamics are carried out with the aim to understand the mechanism of electric field influence on biomass gasification, combustion of volatiles and heat energy production. The DC electric field effect on combustion dynamics was studied by varying the positive bias voltage of the central electrode from 0.6 kV to 3 kV, whereas the ion current was limited to 2 mA. The results of experimental investigations confirm the …