Valorization of oat hull fiber from agri-food industrial waste as filler for poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Journal of Material Cycles and Waste Management - Oat hull fibers are an agri-food industrial waste used in this research as a filler for a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) matrix, to...     

A SEMI-DISTRIBUTED ADAPTIVE MODEL FOR REAL-TIME FLOOD FORECASTING1

ABSTRACT: A semi-distributed deterministic model for real-time flood forecasting in large basins is proposed. Variability of rainfall and losses in space is preserved and the effective rainfall-direct runoff model segment based on the Clark procedure is incorporated. The distribution of losses in space is assumed proportional to rainfall intensity and their evolution in time is represented by the φ-index; furthermore, an initial period without production of effective rainfall is considered. The first estimation of losses and the associated forecasts of flow are performed at the time corresponding to the first rise observed in the hydrograph. Then the forecasts of flow are corrected at each subsequent time step through the updating of the φ-index. The model was tested by using rainfall-runoff events observed on two Italian basins and the predictions of flow for lead times up to six hours agree reasonably well with the observations in each event. For example, for the coefficient of persistence, which compares the model forecasts with those generated by the no-model assumption, appreciable positive values were computed. In particular, for the larger basin with an area of 4,147 km², the mean values were 0.4, 0.4 and 0.5 for forecast lead times of two hours, four hours and six hours, respectively. Good performance of the model is also shown by a comparison of its flow predictions with those derived from a unit hydrograph based model     

Novel insights in Al-MCM-41 precursor as adsorbent for regulated haloacetic acids and nitrate from water

High concentration of NO ₃ ^? in groundwater has raised concern over possible contamination of drinking water supplies. In addition, the formation of haloacetic acids (HAAs) as by-products during disinfection with chlorine-based agents is still a relevant issue, since HAAs pose serious health hazard. In this work, we investigated the affinity of a precursor of Al-MCM-41 (a mesostructured hexagonal aluminosilicate containing the template surfactant) towards nitrate and HAAs, for its possible application in the removal of these pollutants from natural and drinking waters. Additionally, adsorption kinetics and isotherms were studied. The adsorbent was synthesized using cetyltrimethylammonium bromide as surfactant and characterized by physico?Cchemical techniques. Simulated drinking water was spiked with the EPA-regulated HAAs (monochloroacetic (MCAA), monobromoacetic (MBAA), dichloroacetic (DCAA), dibromoacetic (DBAA), and trichloroacetic (TCAA) acids) and placed in contact with the adsorbent. The effect of matrix composition was studied. Adsorption kinetic studies were performed testing three kinetics models. For the adsorption studies, three adsorption isotherm approaches have been tested to experimental data. The pollutant recoveries were evaluated by suppressed ion chromatography. The affinity of the adsorbent was TCAA = DBAA = DCAA > MBAA > MCAA with DCAA, DBAA, and TCAA completely removed. A removal as high as 77?% was achieved for 13?mg/L nitrate. The adsorption isotherms of NO ₃ ^? and monochloroacetic acid can be modeled by the Freundlich equation, while their adsorption kinetics follow a pseudo-second-order rate mechanism. The adsorbent exhibited high affinity towards HAAs in simulated drinking water even at relevant matrix concentrations, suggesting its potential application for water remediation technologies.     

Coastal dune development and morphological changes along the littorals of Garigliano,Italy, and Elis,Greece, during the Holocene

Geomorphological and sedimentological studies were carried out along the Garigliano and Elis littorals with the aim to highlight if similar geoenvironmental features are controlled by same coastal processes. Actually, both sites are in Mediterranean climate regions very far each other, modeled by western winds and storms, characterized by wide sandy coastal dunes parallel to the present shoreline, with abundant pumices, and locally anthropized. The Garigliano littoral is characterized by Holocene dune and Pleistocene aeolian deposits. The beach is bounded landwards by a dune system emplaced during the Holocene. Geoarchaeological surveys highlighted the presence of a Roman road which cut the dune, with age older than Graeco-Roman Period. Since the end of the 1950’s, strong littoral retreat affected the beach-dune system, partly due to human activity. The coastland of Elis is characterized by Quaternary marine deposits. Three significant morphogenetic phases occurred during the Holocene. During the last phase, from Graeco-Roman Period to current, shoreline retreat and deposition of aeolian sands occurred. Geoarchaeological evidences suggest that this phase is related to a sea-level lowstand followed by a slow sea-level rise up to the present position, and by humid-temperate climate. Geomorphological surveys of the dunes of Garigliano and Elis, each other compared, suggest that the main phases of their development are related to the effects of climatic conditions, sea-level changes, and secondly to the recent anthropization. The coarse pumices found on both beaches of Campania and Peloponnese regions show the same mineralogical and petrographic features, so we assumed that they likely originated from the Aeolian Arc, southern Italy, which have same composition. These pumices reached the studied coasts by flotation, under the influence of winds and marine surface currents from the southwest-southeast and northwest-west respectively, participating to local coastal processes and representing a good geoindicator of long-distance drift. Precisely for these morphologically converging aspects, such distant sites have been selected and compared.     

Tsunami Survey Expedition: Preliminary Investigation of Maldivian Coral Reefs Two Weeks After the Event

On December 26th 2004, a earthquake west of Sumatra generated a devastating tsunami. Hundreds of thousands of people fell victim. Economic losses were greatest in those countries dependant on tourism. The impact in the Maldives on persons and things was modest. Immediately following the event and notwithstanding the lack of scientific data, the mass media gave catastrophic reports on the state of coral reefs in the area. This paper reports on the first survey on coral reefs in the Maldives after the Tsunami. Ocean walls, passes, inner reefs, and shoals in the North and South Malé atolls, were surveyed two weeks after the event. Significant damage was recorded in the passes in the South Malé atoll. Our observations showed that the damage was more or less extensive depending on latitude and topography. Sri Lanka may have broken the wave’s rush, reducing the extent of the impact on northern atolls. The water’s acceleration inside the passes was so intense as to cause reef collapses. The observed damage represents a minimum fraction of the entire coral reef system. Tourist perception of the area seems unchanged. These data may be used to disseminate correct information about the state of Maldives coral reefs, which would be useful in relaunching local economy.     

Effects of organophosphate compounds on a soil protist, Colpoda inflata (Ciliophora, Colpodidae)

Many investigations on protists indicate that they play an important role in agricultural soils. We have tested the effects of three organophosphate (OP) pesticides, basudin, cidial, and fenix, on the soil ciliate Colpoda inflata, and examined its viability, fission rate, ability to excyst and extrude macronuclear chromatin into cytoplasm. Exposure to these OPs caused a dose-dependent effect on cell viability, and significantly reduced the mean fission rate at a concentration of 1/10(5) v/v. After exposure of resting cysts to 1/10(5) v/v or 1/10(6) v/v concentrations of basudin or cidial, the number of excysted cells was significantly lower than that of the controls. Conversely, exposure to a 1/10(5) v/v fenix concentration did not affect excystment and exposure to 1/10(6) v/v was found to promote excystment. Moreover, exposure to these OPs (1/10(4) v/v or 1/10(5) v/v) interferred with the ability to extrude macronuclear chromatin. The median lethal concentration in 60 min for each OPs tested was at least a hundred times lower than the doses recommended by the manufacturer. Finally, as the inhibition of cholinesterase (ChE) activity is the first target of OPs, the presence of ChE activity was checked in C. inflata. Three ChE activities were found, hydrolyzing the substrates acetyl-beta-methyl thiocholine iodide, propionyl thiocholine iodide and butyryl thiocholine iodide, that appeared to be very low and not inhibited by OP-exposure.