1,721,376 research outputs found
Barco a corda: parte 2
No full textEnsino Fundamental Final::Ciências NaturaisEnsino Médio::FísicaEste vídeo é a segunda parte do experimento "Barco a corda". O vídeo explica como funciona o barco a corda usando os conceitos de energia potencial e energia cinétic
Barco a corda: parte 2
No full textEste vídeo é a segunda parte do experimento "Barco a corda". O vídeo explica como funciona o barco a corda usando os conceitos de energia potencial e energia cinéticaEnsino Médio::FísicaEnsino Fundamental Final::Ciências Naturai
Barco a corda: parte 1
No full textEste vídeo é a primeira parte do experimento "Barco a corda". O vídeo explica e demonstra como montar um barco a corda usando materiais de baixo custoEnsino Fundamental Final::Ciências NaturaisEnsino Médio::Físic
Barco a corda: parte 1
No full textEste vídeo é a primeira parte do experimento "Barco a corda". O vídeo explica e demonstra como montar um barco a corda usando materiais de baixo custoEnsino Fundamental Final::Ciências NaturaisEnsino Médio::Físic
Barco a corda: parte 1
No full textEnsino Médio::FísicaEnsino Fundamental Final::Ciências NaturaisEste vídeo é a primeira parte do experimento "Barco a corda". O vídeo explica e demonstra como montar um barco a corda usando materiais de baixo cust
Barco a corda: parte 1
No full textEnsino Médio::FísicaEnsino Fundamental Final::Ciências NaturaisEste vídeo é a primeira parte do experimento "Barco a corda". O vídeo explica e demonstra como montar um barco a corda usando materiais de baixo cust
Ornamental plants for floating treatment wetlands: Preliminary results
Full text linkFloating treatment wetlands (FTWs) represent a novel ecotechnology for the treatment of different types of wastewaters in natural or artificial water bodies, through the use of traditional rooted emergent macrophyte species supported by floating rafts. Although many studies have reported the treatment performances of FTWs, showing an excellent aptitude for removing nutrients, heavy metals as well as suspended solids, the investigation of vegetation has not received much attention up to now, especially for herbaceous ornamental plant species that could form an interesting opportunity to improve water quality and the esthetic-ornamental value of urban water bodies. For this reason, a pilot scale FTW was installed in Northern Italy to assess the growth performances of eleven wetland species having ornamental features: Canna indica L., Pontederia cordata L., Thalia dealbata Fraser ex Roscoe, Acorus calamus L., Juncus effusus L., Iris laevigata L., Mentha aquatica L., Oenanthe javanica (Blume) DC., Caltha palustris L., Sparganium erectum L. and Zantedeschia aetiopica (L.) Srengel. For these species, a suitability index was elaborated that considers plant survivability, above-mat biomass production, nitrogen uptake, root length and root-shoot ratio. On this basis, the results obtained clearly indicated that C. indica, P. cordata and T. dealbata were the most suitable species for FTW due to their high vigor and colonization of the floating mats (1638.9 g m(-2), 483.4 g m-2, 566.1 g m(-2) of above-mat dry biomass, respectively; 38.8 cm, 62.0 cm, 43.8 cm root length, respectively; 0.8, 0.9, 1.2 root-shoot ratio, respectively), survival (100%), nitrogen uptake (15.1 g m(-2), 15.0 g m(-2), 15.7 g m(-2) respectively). On the contrary, A. calamus, S. erectum and Z. aetiopica did not present adequate features for use in FTWs
Treatment performances of floating wetlands: A decade of studies in North Italy
No full textFloating treatment wetlands (FTWs) are one of the most recent eco-technologies to treat low-quality polluted wastewaters in already existing retention ponds, without subtracting other soil surface for the treatment of wastewaters. This study assessed the depuration performances of eight different FTWs (1 pilot-scale and 7 full-scale plants) treating municipal wastewaters, agricultural runoff and digestate liquid fraction, in North Italy. The concentration of different pollutants was monitored before and after the FTWs barriers: total nitrogen (TN), nitrate nitrogen (NO3-N), ammonia nitrogen (NH4-N), total phosphorus (TP), orthophosphate (PO4-P), chemical oxygen demand (COD) and turbidity. Considering all the case studies, pollutants inflowing concentrations were highly variable, due to the different composition of wastewaters used in the trials (TN: 0.3–520.0 mg L−1, median value 19.1 mg L−1; NO3-N: <0.001–61.5 mg L−1, median value 2.6 mg L−1; NH4-N: <0.001–310.0 mg L−1, median value 3.6 mg L−1; TP: 0.02–44.9 mg L−1, median value 5.7 mg L−1; PO4-P: <0.001–32.9 mg L−1, median value 4.1 mg L−1; COD: 2.1–6152.0 mg L−1, median value 67.5 mg L−1). Wastewater nitrogen forms and COD concentrations were reduced after passing the FTW with median abatements of 44.1% for TN, 34.6% for NO3-N, 16.7% for NH4-N, and 25.2% for COD. Only Phosphorus concentrations were not affected by the FTWs. Wastewater turbidity ranged from 3.4 to 3075.0 NTU and the median value of 77.7 NTU was significantly reduced by 22.1% after the FTWs, thus suggesting that plant root systems were active in physical wastewater filtration. In three case studies E. coli was also monitored and abatements ranged from 19.5 and 95.1%. The results obtained after ten years of study indicated that FTWs represented an efficient and economic wastewater management system, which provided a positive ecosystem service and therefore reduced the human footprint on the environment
Oxocyclopentenes, Synthesis of 2-Methoxy-4-methyl-3-oxocyclopentene and its Conversion to Di-hydrojasmone
No full textA new synthesis of dihydrojasmone starting from the disodium salt 3,5-diehthoxycarbonil-1,2-dioxocyclopentane,readly avalable by Thaoker-Bagavant procedure ,is reported
A facile alkylation of ethyl 2-oxocyclopentanecarboxylate
No full textA very simple procedure that allows to alkylate the Dieckman ester is reported
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