Search results for "Biomas"
showing 10 items of 980 documents
LE METODICHE ANALITICHE
2022
Il processo analitico è frutto di una serie di tappe fondamentali (Fig. 13.1) che devono permettere di raggiungere lo scopo prefissato: ottenere un’informazione puntuale sul campione sottoposto ad analisi. Le scelte legate alla procedura di campionamento, di pretrattamento del campione e del metodo di analisi sono fortemente influenzate dal tipo di matrice, dal tipo di analita o del parametro da determinare e dal grado di incertezza tollerabile sul risultato finale affinché sia conforme alle esigenze normative, disciplinari o di indagine scientifica. Il campione, inteso come quantità di materia che si sottopone ad analisi, deve essere un’aliquota rappresentativa e omogenea della biomassa ne…
Assessment of bioenergy potential in Sicily: a GIS-based support methodology
2008
Abstract A Geographical Information System (GIS) supported methodology has been developed in order to assess the technical and economic potential of biomass exploitation for energy production in Sicily. The methodology was based on the use of agricultural, economic, climatic, and infrastructural data in a GIS. Data about land use, transportation facilities, urban cartography, regional territorial planning, terrain digital model, lithology, climatic types, and civil and industrial users have been stored in the GIS to define potential areas for gathering the residues coming from the pruning of olive groves, vineyards, and other agricultural crops, and to assess biomass available for energy cu…
Sorption of copper(II) ions in the biomass of alga Spirogyra sp.
2012
Abstract Sorption of copper ions by the alga Spirogyra sp. was investigated to determine the influence of experimental conditions and the methods of sample preparation on the process. The experiments were carried out both under the static and the dynamic conditions. Kinetics and equilibrium parameters of the sorption were evaluated. In addition, the influence was studied of the algae preparation methods on the conductivity of demineralized water in which the algae samples were immersed. The static experiments showed that the sorption of Cu2+ ions reached equilibrium in about 30 min, with approximately 90% of the ions adsorbed in the initial 15 min. The sorption capacity determined from the …
Designing biochar properties through the blending of biomass feedstock with metals: Impact on oxyanions adsorption behavior
2018
Metal-blending of biomass prior to pyrolysis is investigated in this work as a tool to modify biochar physico-chemical properties and its behavior as adsorbent. Six different compounds were used for metal-blending: AlCl3, Cu(OH)2, FeSO4, KCl, MgCl2 and Mg(OH)2. Pyrolysis experiments were performed at 400 and 700 °C and the characterization of biochar properties included: elemental composition, thermal stability, surface area and pore size distribution, Zeta potential, redox potential, chemical structure (with nuclear magnetic resonance) and adsorption behavior of arsenate, phosphate and nitrate. Metalblending strongly affected biochars' surface charge and redox potential. Moreover, it incre…
Optimizing the Sampling Area across an Old-Growth Forest via UAV-Borne Laser Scanning, GNSS, and Radial Surveying
2022
Aboveground biomass, volume, and basal area are among the most important structural attributes in forestry. Direct measurements are cost-intensive and time-consuming, especially for old-growth forests exhibiting a complex structure over a rugged topography. We defined a methodology to optimize the plot size and the (total) sampling area, allowing for structural attributes with a tolerable error to be estimated. The plot size was assessed by analyzing the semivariogram of a CHM model derived via UAV laser scanning, while the sampling area was based on the calculation of the absolute relative error as a function of allometric relationships. The allometric relationships allowed the structural …
Environmental assessment of a waste-to-energy practice: The pyrolysis of agro-industrial biomass residues
2021
Abstract The bio-wastes pyrolysis is a waste to energy strategy that converts bio-wastes into valuable products (bio-char, bio-oil) with wide use in the agri-food sector. However, limited efforts are paid to the investigation of its environmental sustainability: in this context, the study contributes the need towards the assessment of a wide range of environmental impacts for the pyrolysis process of different types of bio-wastes under different operating conditions. The study estimates the potential environmental impacts related to bio-char production from the pyrolysis of several different agro-industrial residues and different temperatures and identifies the process “hot spots”. The anal…
Influence of Nutrients and Mixing on the Primary Production and Community Respiration in the Gulf of Riga
1999
Abstract Rates of plankton community production and respiration in relation to wind, solar radiation, biomass and nutrients were measured in the mixed layer during a late spring, a mid-summer and an early autumn situation in the Gulf of Riga. System metabolism was estimated by the in vitro oxygen method and from oxygen mass balance directly in the water. Gross production (GPP) remained fairly stable throughout the investigation periods with a mean of 1.8 g C m−2 day−1 (range: 0.5–3.9 g C m−2 day−1). Community respiration varied from 0.5 to 6.4 g C m−2 day−1 during the two summer studies (the high respiration rates ranging from 3.0 to 10.4 g C m−2 day−1 found during the autumn cruise were pr…
Economic performance of biogas plants using giant reed silage biomass feedstock
2015
Abstract With regard to energy crops for the production of raw materials to biomass for biogas plants, has developed a study to determine the optimal minimum size of a biogas plant powered by giant reed (Arundo donax L.) and utilizing livestock waste. In particular, all costs items relating to biomass supply, plant installation and transport costs were analyzed, by changing progressively two main variables: the electrical power capacity and the feedstock utilized (in the range from 100 to 999 kW) and the feedstock utilized, by substituting livestock waste with giant reed silage so as to determine the more economically advantageous option for the entrepreneur in proportion to power capacity …
Economic evaluation of biogas plant size utilizing giant reed
2015
Abstract Amongst energy crops for the production of biomass feedstock for biogas plants, giant reed (Arundo donax L) has been attracting attention in recent years in Italy. Undoubtedly, this is due to its potentially high yield in terms of biomass, low agronomic inputs, as well as for being eligible for European Union energy crop incentives. The aim of this study was to perform an analysis of plant costs considering three macro-categories (biomass, plant installation and transport). Also, we aimed to describe the economic performances of biogas plants, while progressively altering two key variables. Specifically, we considered electrical power capacity (in the 100–999 kW range) and several …
Global distributions of diazotrophs Gamma-A nifH genes abundance - Depth integrated values computed from a collection of source datasets - Contributi…
2013
The MAREDAT atlas covers 11 types of plankton, ranging in size from bacteria to jellyfish. Together, these plankton groups determine the health and productivity of the global ocean and play a vital role in the global carbon cycle. Working within a uniform and consistent spatial and depth grid (map) of the global ocean, the researchers compiled thousands and tens of thousands of data points to identify regions of plankton abundance and scarcity as well as areas of data abundance and scarcity. At many of the grid points, the MAREDAT team accomplished the difficult conversion from abundance (numbers of organisms) to biomass (carbon mass of organisms). The MAREDAT atlas provides an unprecedente…