Preparation and characterization of activated carbon from a new raw lignocellulosic material: Flamboyant (Delonix regia) pods

Activated carbons were prepared from flamboyant pods by NaOH activation at three different NaOH:char ratios: 1:1 (AC-1), 2:1 (AC-2), and 3:1 (AC-3). The properties of these carbons, including BET surface area, pore volume, pore size distribution, and pore diameter, were characterized from N₂ adsorption isotherms. The activated carbons obtained were essentially microporous and had BET surface area ranging from 303 to 2463 m² g⁻¹.¹³C (CP/MAS and MAS) solid-state NMR shows that the lignocellulosic structures were completely transformed into a polycyclic material after activation process, thermogravimetry shows a high thermal resistance, Boehm titration and Fourier-transform infrared spectroscopy allowed characterizing the presence of functional groups on the surface of activated carbons. Scanning electron microscopy images showed a high pore development. The experimental results indicated the potential use of flamboyant pods as a precursor material in the preparation of activated carbon.     

Uptake,transformation, and elimination kinetics of paralytic shellfish toxins in white seabream (<Emphasis Type="Italic">Diplodus sargus</Emphasis>)

Marine toxins generated by harmful algal blooms can be transferred through the marine food web and ultimately cause massive deaths of piscivorous predators. However, very few studies have explored the processes of accumulation and biotransformation of paralytic shellfish toxins (PSTs) within fishes. White seabream (Diplodus sargus) were orally challenged with contaminated cockles (Cerastoderma edule) containing N-sulfocarbamoyl and decarbamoyl toxins and non-contaminated cockles afterwards. Specific PSTs that occurred in low abundance in cockles (B1 7.6% and dcSTX 1.6% molar fraction) were the only toxins detected in fish viscera possibly resulting from selective elimination and transformation of the various PSTs. Concentration of toxins progressively increased in fish viscera throughout the uptake period. Toxins were then rapidly depurated (B1 0.905 day⁻¹, dcSTX 0.467 day⁻¹) when diet was changed to non-toxic cockles. Results indicate conversion of a precursor toxin into B1 which in turn might be converted into dcSTX at a lower extent. Low accumulation efficiency of 1.7 and 5.0% was calculated to B1 and dcSTX, respectively. This study contributes to a better understanding of dynamics of PSTs in fish and the fate of these compounds in the marine food web.     

Soil organic matter dynamics in Portuguese natural and sown rainfed grasslands

Soil organic matter (SOM) is a particularly important parameter in soil management, especially in mineral soils in Mediterranean and semi-arid countries where its concentration is low. In these conditions, increasing SOM concentration has several agronomic and environmental benefits, ranging from increase in water holding capacity to soil protection and carbon sequestration. We develop a model to express the short-term trend of SOM increase in grasslands as the balance between input and mineralization. This model is calibrated using five years of soil analyses from eight locations. In each location there were either two or three plots with the different grassland systems considered: sown biodiverse permanent pastures rich in legumes (SBPPRLs), fertilized natural grasslands (FNGs), and (un-improved) natural grasslands (NGs). SBPPRL are a new system consisting in the use of plant biodiversity to increase pasture productivity and resilience. So far, they exist mostly in Portugal.We use statistical calibration to adjust an asymptotic curve to the data and obtain the model parameters. Under the assumption of equal mineralization rates across grassland systems, we find that the expected steady-state long term SOM concentration in undisturbed SBPPRL is higher than in NG and FNG. Fertilization does not significantly increase SOM input, and so the trend in SOM is equal for NG and FNG. In 10 years, there is an average increase of 0.21 percentage points per year in SBPPRL. In turn, SOM increases in FNG and NG are 0.08 percentage points per year.     

Photoelectro-Fenton treatment of pesticide triclopyr at neutral pH using Fe(III)–EDDS under UVA light or sunlight

Environmental Science and Pollution Research - One of the main challenges of electrochemical Fenton-based processes is the treatment of organic pollutants at near-neutral pH. As a potential...     

Photochemical persistence of sulfa drugs in aqueous medium: kinetic study and mathematical simulations

Environmental Science and Pollution Research - This study aimed at investigating the photochemical behavior of sulfa drugs containing five and six-membered heterocyclic substituents...     

An updated review on cattle thermoregulation: physiological responses,biophysical mechanisms,and heat stress alleviation pathways

Environmental Science and Pollution Research - Heat stress is one of the main obstacles to achieving efficient cattle production systems, and it may have numerous adverse effects on cattle. As the...     

The link between pharmaceuticals and cyanobacteria: a review regarding ecotoxicological,ecological, and sanitary aspects

Environmental Science and Pollution Research - Cyanobacteria are important for ecosystem functioning, but eutrophication may affect the surrounding biome by losing ecosystem services and/or through...     

Lethal and sublethal effects of the natural and healthy spinosad-based formulation Tracer™ on tadpoles of two neotropical species

Environmental Science and Pollution Research - This paper presents the first acute toxicity data of the natural insecticide spinosad in amphibians. The sensitivity of two neotropical sympatric...     

Group decision-making for leakage management strategy of water network

The problem of leakage is complex and requires actions drawn from different aspects of water network management. Inadequate maintenance has serious consequences, both financial and environmental. This paper proposes a group decision-making model based on PROMETHEE V method to aim a leakage management strategy, which takes into account the points of view of four stakeholders, selecting feasible options, and considering the available budget as constraint. Thus, this strategy is the combination of options that will efficiently meet technical, socio-economic and environmental criteria to achieve sustainable development.