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Registros recuperados: 15 | |
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Barrut, Bertrand; Blancheton, Jean-paul; Champagne, Jean-yves; Grasmick, Alain. |
In aquaculture, oxygen transfer and carbon dioxide stripping are the first limiting factors to fish rearing intensification. In this study we measured the O-2 and CO2 mass transfer coefficient (K(L)a) for a vacuum airlift in fresh (<1% salinity) and sea water (35 parts per thousand salinity) recirculating aquaculture systems (RAS). The airlift was composed of two concentric tubes: an inner riser tube and an external downcomer tube and can be adjusted at three different heights: 2,4 or 6 m. Several types of air injectors were tested, delivering different sizes of bubble swarms depending on their porosity and functioning conditions (low or high injection pressure), with air flows varying from 0 to 80 L min(-1). Experiments were also carried out at... |
Tipo: Text |
Palavras-chave: Mass transfer; Airlift; Vacuum; Aquaculture; RAS; Aeration; Degasification; Salinity. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00072/18324/16001.pdf |
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Holbach, Marine; Robert, Rene; Miner, Philippe; Mingant, Christian; Boudry, Pierre; Tremblay, Rejean. |
Hatchery production of great scallop, Pecten maximus, remains unpredictable, notably due to poor larval survival. Large-scale flow-through systems up to 3500 L have been developed to avoid the use of antibiotics in static systems. Alternatively, small-scale flow-through systems have been successfully applied for oysters but they proved to be unsuitable to rear scallop larvae. By focusing on physical factors presumed to limit P. maximus larval development, this study aimed to optimize great scallop larvae rearing parameters under controlled conditions. First, the influence of aeration on larval performances, energetic metabolism and antioxidant defences were studied both in static and flow-through systems. Aeration depressed larval food intake, regardless... |
Tipo: Text |
Palavras-chave: Aeration; Flow-through; Larval physiology; Pecten maximus. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00384/49508/51151.pdf |
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Ururahy,Adriana F. P.; Marins,Marcus D. M.; Vital,Ronalt L.; Gabardo,Irene Therezinha; Pereira Jr.,Nei. |
Large amounts of oily sludge are generated as residues by the oil industry, representing a real problem for refineries. This work studied the technical viability of treating oily sludge biologically, through stimulation of native microorganisms, at bench scale. Such microorganisms were able to grow in a medium containing oily sludge as the only carbon and energy sources. Two oily sludge concentrations were studied, 5% (v/v) and 10% (v/v), with a C:N ratio of 100:1. Higher microbial populations were observed in the first case. Substrate inhibition and/or toxic effect took place in the second case. The importance of aeration on the microbial activity and on the biodegradation of the residue was ascertained. In terms of n-paraffins, pristane and phytane... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Petroleum waste; Biodegradation; Aeration. |
Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000400004 |
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Silva, Nara Cristina Lima; UFV; Matos, Antonio Teixeira; DEA/UFV; Sartori, Marcia Aparecida; UFV; Moreira, Debora Astoni; UFV; Barros, Renata Tamara Pereira de; UFV; Luiz, Fatima Aparecida Rezende; UFV. |
Pouco se sabe sobre as necessidades de potência do ventilador, com o tempo, na na compostagem do material em leiras estáticas aeradas. Objetivou-se, com a realização deste trabalho, ajustar curvas de variação na pressão estática do ar, quando forçado em pilhas de material orgânico em diferentes estádios de degradação bioquímica. Para a condução do mesmo, montou-se uma pilha de compostagem com bagaço de cana-de-açúcar (BC) e cama de frango (CF), preparando-se a mistura de forma a se obter uma relação C/N inicial de 30/1. O material foi revolvido a cada três dias, durante o primeiro mês e a cada cinco dias, nos dois meses posteriores. No BC, nas condições tal como foi utilizado na mistura, e no material da mistura BC + CF, nas condições em que se encontravam... |
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Palavras-chave: 5.03.04.02-0 Engenharia de Construções Rurais compostagem; Leiras estáticas aeradas; Aeração 5.03.04.02-0 Engenharia de Construções Rurais composting; Aerated static piles; Aeration. |
Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/1790 |
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Vinatea, Luis; UFSC; Muedas, Walter; UFMA; Arantes, Rafael; UFSC. |
A simulation was conducted to determinate the impact caused by the combination of Litopenaeus vannamei respiratory rate (mg O2 shrimp-1 h-1), the behavior of SOTR (kg O2 h-1) of mechanical aerators as a function of salinity, as well as the oxygen consumption rate of the pond water and soil (mg O2 L-1 h-1) on the aeration of shrimp ponds (1, 10, 50 and 100 ha) stocked with different densities (10, 40 and 120 shrimp m-2), salinities (1, 13, 25 and 37 ppt), temperatures (20, 25 and 30°C), and shrimp wet weight (5, 10, 15 and 20 g). Results showed that under lower salinity, with larger shrimp, and higher stocking density, higher will be the quantity of required 2-HP aerators to keep dissolved oxygen over 50% saturation. In addition, under low salinity, with 5... |
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Palavras-chave: Aeration; Shrimp farming; Respiration; Oxygen consumption; Density Aeration; Shrimp farming; Respiration; Oxygen consumption; Density. |
Ano: 2011 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/7018 |
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Park, Kyu-Hyun; Ngwabie, Ngwa Martin; Wagner-Riddle, Claudia. |
Composting has the potential to mitigate methane (CH4) and nitrous oxide (N2O) emissions from manure. The heterogeneous nature of emitting surfaces makes it difficult to quantify these emissions. CH4 and N2O fluxes measured using eight small chambers (0.72 m2) and a mega chamber (90 m2) were compared, and the effect of aeration on the fluxes during composting was studied. Two batches of compost were placed in three channels and 2-3 small flux chambers were deployed on each channel. The channels were enclosed by a building serving as a mega chamber. Chamber location significantly affected gas fluxes, pointing to strong spatial heterogeneity. Mean CH4 fluxes from the small chambers were similar or 1.4 times higher compared to the mega chamber. Mean... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chamber; Compost; Greenhouse gases; Aeration; Flux. |
Ano: 2014 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2467 |
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Kyu-Hyun Park; Ngwa Martin Ngwabie; University of Guelph; Claudia Wagner-Riddle. |
Composting has the potential to mitigate methane (CH4) and nitrous oxide (N2O) emissions from manure. The heterogeneous nature of emitting surfaces makes it difficult to quantify these emissions. CH4 and N2O fluxes measured using eight small chambers (0.72 m2) and a mega chamber (90 m2) were compared, and the effect of aeration on the fluxes during composting was studied. Two batches of compost were placed in three channels and 2-3 small flux chambers were deployed on each channel. The channels were enclosed by a building serving as a mega chamber. Chamber location significantly affected gas fluxes, pointing to strong spatial heterogeneity. Mean CH4 fluxes from the small chambers were similar or... |
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Palavras-chave: Chamber; Compost; Greenhouse gases; Aeration; Flux. |
Ano: 2014 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2467 |
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LIMA NETO,IRAN E.. |
Abstract: Field surveys and integral modelling were carried out to study the effect of bubble plumes on the flow hydrodynamics and the time-evolution of water temperature profiles in a shallow lake with maximum depth of about 4 m. Then, model simulations were performed to verify the feasibility of destratification of ten water-supply reservoirs with capacities of 10-2,000 hm3. Finally, hydrological modelling was conducted to assess the impact of destratification on evaporation suppression and its effects on reservoir yield. The results indicate that net temperature reductions of the order of 1.0°C can be obtained, which corresponds to evaporation suppressions of approximately 10%. In turn, this resulted in increases in the regulated flow of 2-12% that... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aeration; Evaporation; Bubble plumes; Lakes; Stratification; Water yield. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000500904 |
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Ronda,Srinivasa Reddy; Bokka,Chandra Sekhar; Ketineni,Chandrika; Rijal,Binod; Allu,Prasada Rao. |
The influence of aeration on algal growth and gamma-linolenic acid (GLA) production in a bubble column photobioreactor was investigated. Studies were performed in a 20-L reactor at different aeration rates (0.2-2.5 vvm). Static, continuous, and periodic operation of air resulted in 41.9%, 88.4%, and 108% air saturation of dissolved oxygen, for which the corresponding values of GLA were 2.3, 6.5, and 7.5 mg·g-1 dry cell weight, respectively. An increase in the aeration rate from 0.2 to 2.5 vvm enhanced both the specific growth rate and GLA content under periodic sparging in the bicarbonate medium. With a 6-fold increase in the aeration rate, the GLA content of the alga increased by 69.64% (5.6-9.5 mg· g-1 dry cell weight). In addition, the total fatty acid... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spirulina platensis; Aeration; Photobioreactor; Gamma-linolenic acid. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822012000100002 |
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Arshad,Muhammad; Hussain,Tariq; Iqbal,Munawar; Abbas,Mazhar. |
Abstract Very high gravity (VHG) technology was employed on industrial scale to produce ethanol from molasses (fermented) as well as by-products formation estimation. The effect of different Brix° (32, 36 and 40) air-flow rates (0.00, 0.20, 0.40, and 0.60 vvm) was studied on ethanol production. The maximum ethanol production was recorded to be 12.2% (v/v) at 40 Brix° with 0.2 vvm air-flow rate. At optimum level aeration and 40 Brix° VHG, the residual sugar level was recorded in the range of 12.5-18.5 g/L, whereas the viable cell count remained constant up to 50 h of fermentation and dry matter production increased with fermentation time. Both water and steam consumption reduced significantly under optimum conditions of Brix° and aeration rate with... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Very high gravity technology; Ethanol; Molasses; Aeration; Brix. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822017000300403 |
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Registros recuperados: 15 | |
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