|
|
|
| Registros recuperados: 35 | |
|
| |
|
| |
|
| |
|
|
| Marín Sosa, Ma. Isabel. |
| Los intercambios de energía y masa entre la superficie de la tierra y la atmósfera controlan la disposición de agua en el planeta, por lo que su conocimiento y modelación es importante. A escalas regionales, como los distritos de riego, el tema se ha abordado usando sensores remotos en satélites, donde el escalamiento de las mediciones de campo a las áreas de influencia o footprints de las observaciones satelitales deben ser intercomparables. A nivel de campo, se ha empleado la técnica de covarianza de vórtices para medir de forma directa los flujos de energía y masa, no obstante, se han encontrado problemas en el cierre de los balances, que se argumenta son producto del uso de diferentes footprints de las componentes del balance de energía. Así, en el... |
|
Palavras-chave: Cierre balance de energía; Modelo uni-paramétrico de la geometría sol-sensor; Temperatura aerodinámica; Eddy Covariance; Temperatura radiativa; Albedo; Balance de energía; Función de distribución bidireccional de la reflectancia; Función de distribución bidireccional de la emisividad; Energy balance closure; Sun-sensor uni-parametric model; Aerodynamic temperature; Eddy covariance technique; Radiative temperature; Energy balance; Bidireccional reflectance distribution function; Bidireccional emissivity distribution function; Hidrociencias; Doctorado. |
| Ano: 2013 |
URL: http://hdl.handle.net/10521/2035 |
| |
|
| |
|
|
| Rennó,Francisco Palma; Freitas Júnior,José Esler de; Gandra,Jefferson Rodrigues; Maturana Filho,Milton; Verdurico,Lenita Camargo; Rennó,Luciana Navajás; Barletta,Rafael Villela; Vilela,Flávio Garcia. |
| The objective of this study was to evaluate the influence of unsaturated fatty acids in diets for dairy cows during the transition period and early lactation on intake, digestion and nutrient balance. Thirty-six multiparous and pregnant Holstein cows were randomly distributed to receive one of the experimental diets in the period from 35 days before the expected date of parturition to 84 days post-partum. Diets were fed as a total mixed ration and were as follows: control (C); soybean oil (SO), based on inclusion of 30 g/kg (DM basis); and calcium salts of unsaturated fatty acids (CS), based on inclusion of 30 g/kg (DM basis). Pre-partum dry matter intakes (DMI) of cows fed C, SO and CS were 11.9, 9.5 and 9.6 kg/d, respectively. Post-partum DMI was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dry matter intake; Energy balance; Ruminant digestion. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982014000400212 |
| |
|
|
| Gaudy, R.; Guerin, J.p.. |
| Following are results obtained in our laboratory during breeding experiments with an harpacticoid copepod, Tisbe holothuriae. In small size volumes (200 ml), the potential production appears to be higher when an artificial compound food of animal substances is used instead of a vegetal diet. In medium volume experiments (100 l) the production is related to the surface available for animals in breeding tanks, Breeding in complete cycles can be obtained using various foods, but the quality of diet may markedly affect the characteristics of the vital cycle, such as the length of the fertility period and fecundity. Temperature has a crucial effect, chiefly on dynamic preoccesses, that is to say, developmental rate and average generation time. With different... |
| Tipo: Text |
Palavras-chave: Production; Dynamique des populations; Biomasse; Composition chimique élémentaire; Bilan énergétique; Copépodes harparcticoïdes; Production; Population dynamic; Biomass; Chemical elementary composition; Energy balance; Hapacticoïd copepods. |
| Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/00306/41672/40881.pdf |
| |
|
|
| Araujo,Alisson V. de; Brandão Junior,Delacyr da S.; Colen,Fernando. |
| The aim of this study was to analyze, under the energetic point of view, the cultivation of corn in three management systems (low, medium and high-tech), using two landrace varieties ('Argentino' and 'BR da Várzea'), a double hybrid cultivar (SHS 4080) and a simple hybrid (IAC 8333). Five performance indicators were used: energy efficiency, liquid cultural energy, cultural efficiency, energy balance and productive energy efficiency. From the perspective of family farming, it was verified the largest social importance of the systems under low and medium levels of technology, due to the increase employment capacity of rural labor. The liquid cultural energy and energy balance were more favorable for the system under high technological level, unlike cultural... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Energy balance; Cultural efficiency; Productive energy efficiency; Sustainability; Zea mays L. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000400004 |
| |
|
|
| Freitas,Cley Anderson Silva de; Bezerra,Francisco Marcus Lima; Silva,Alexandre Reuber Almeida da; Albiero,Daniel; Nascimento,José Adeilson Medeiros do. |
| ABSTRACT Using energy balance methodology, this study compared the sustainability of ethanol synthesis from sugarcane irrigated with different replacement levels based on the evaporation estimated in a Class A pan (ECA), using treated domestic sewage effluent and groundwater as the water source, in Aquiraz, in the State of Ceará. The adopted statistical design was of randomised blocks in split plots, with four replications. Two water sources (treated sewage effluent and groundwater) were evaluated in the plots, and five irrigation levels (50, 75, 100, 125 and 150% of the ECA) were evaluated in the split plots. Irrigation with treated domestic sewage effluent results in greater energy expenditure. The irrigation depth relative to 150% of the ECA expends the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Reuse of water; Energy balance; Saccharum officinarum L.. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000300389 |
| |
|
|
| Dalla Marta, Anna; DIPSA-University of Firenze; anna.dallamarta@unifi.it; Natali, Francesca; DIPSA-University of Firenze;; Mancini, Marco; DIPSA-University of Firenze;; Ferrise, Roberto; DIPSA-University of Firenze;; Bindi, Marco; DIPSA-University of Firenze;; Orlandini, Simone; DIPSA-University of Firenze;. |
| The contribution of agrobiomasses, as a source of energy, to the reduction of greenhouse gas emissions was confirmed by several studies. Biomass from agriculture represents one of the larger and more diverse sources to exploit and in particular ethanol and diesel have the potential to be a sustainable replacement for fossil fuels, mainly for transport purposes. However, the cultivation of energy crops dedicated to the production of biofuels presents some potential problems, e.g., competitiveness with food crops, water needs, use of fertilizers, etc., and the economic, energy, and environmental convenience of such activity depends on accurate evaluations about the global efficiency of the production system. In this study, the processes related to the... |
| Tipo: Peer-Reviewed Insight |
Palavras-chave: Agroenergy; Bioethanol; Energy balance; Pure vegetable oil; Water balance. |
| Ano: 2011 |
|
| |
|
|
| Luchiari Jr.,A.; Riha,S. J.; Gomide,R.L.. |
| To evaluate the water requirements for irrigated wheat, a micrometeorological study was conducted during the dry seasons of 1982 and 1983 at the Cerrados Agricultural Research Center, Brasilia-DF, Brazil The crop was irrigated when the soil water potential at 5 cm rached -60 to -70J/Kg.Bowen ratio measurements were made on an hourly basis during the entire crop season. Total amount of water evapotranspired during the crop cycle and the energy balance terms varied year to year due to regional advection; In 1982, a less advective year, the total amount of water evapotranspired was 345 mm, with approximately 80% of the net radiation dissipated as latent heat, 13% as a sensible heat and 7% as soil heat after the crop obtained a Leaf Area Index (LAI) of 1.5. In... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Energy balance; Irrigated wheat; Cerrado. |
| Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161997000300011 |
| |
|
|
| Franco Junior,Nelson C.; Milan,Marcos; Romanelli,Thiago L.. |
| Citrus orchards are very important in Brazil, especially in São Paulo State, where occupy an area of 600,000 ha approximately. To identify sustainability degree of citrus production system, an energy analysis allows evaluating efficiency of direct and indirect applied inputs. Thus, this study aimed to evaluate citrus production system under energetic point of view, in which invested energy is paid back with citrus production; being compared within three scenarios for operational field efficiency. As result, by sensitivity analysis was determined that fuel was the main energy demander, followed by pesticides and fertilizers. In operational work capacity analysis, all combinations between efficiency (minimum, typical and maximum) and yield levels became... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Energy balance; EROI; Machinery management; Sustainability. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000400014 |
| |
|
|
| Veiga,João Paulo Soto; Romanelli,Thiago Libório; Gimenez,Leandro Maria; Busato,Patrizia; Milan,Marcos. |
| The amount of energy required to produce a commodity or to supply a service varies from one production system to another and consequently giving rise to differing levels of environmental efficiency. Moreover, since energy prices have been continuously increasing over time, this energy amount may be a factor that has economic worth. Biomass production has a variety of end-products such as food, energy, and fiber; thus, taking into account the similarity in end-product of different crops (e.g.: sunflower, peanuts, or soybean for oil) it is possible to evaluate which crops require less energy per functional unit, such as starch, oil, and protein. This information can be used in decision-making about policies for food safety or bioenergy. In this study, 23... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: EROI; Starch; Oil; Fertilizer; Fiber; Energy balance. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000600471 |
| |
|
| |
|
|
| Romanelli,Thiago L.; Milan,Marcos. |
| Maximizing yields is opposed to the goal of minimizing the use of inputs. In the context of system rationalization, the addition of non-economic parameters in the decision making and the magnitude of eucalyptus plantation in Sao Paulo State, Brazil led to this study. The objective was to establish the flows and to evaluate the performance of energy transformations on eucalyptus production. The evaluated system presented three alternatives of soil acidity management: lime, ash and sludge application. The applied indicators were energy return on investment, energy intensity and energy balance, which meant, respectively, the return over energy investment, the energy content of biomass and the energy obtained per area. For the basic scenario, lime, EROI was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sustainability; Environmental analysis; EROI; Energy balance. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662010000800015 |
| |
|
| |
|
|
| Mantoam, Edemilson J; Mekonnen, Mesfin M; Romanelli, Thiago Libório. |
| The intensification of agricultural production systems demand power, supplied by agricultural machinery, besides more agricultural inputs such as fertilizer, pesticides and seeds. Agricultural mechanization provided increase in the global production of food, fiber and bioenergy; and it brought economic benefits to producers, but causing larger energy consumption. Energy embodiment in agricultural machinery has been approached, but data usually are from car industry. This study aimed to determine the energy demand in a plant that assembles five types of agricultural machinery from a multinational manufacturer located in Piracicaba municipality in Sao Paulo state, Brazil. That plant assembles two types of sugarcane harvester, coffee harvesters, sprayers and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Agricultural engineering mechanization; Industrial process; Life cycle assessment; Energy balance; Sustainability. |
| Ano: 2018 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/4831 |
| |
|
| |
|
|
| Bezerra,Bergson Guedes; Santos,Carlos Antonio Costa dos; Silva,Bernardo Barbosa da; Perez-Marin,Aldrin Martin; Bezerra,Marcus Vinícius Cândido; Bezerra,José Renato Cortez; Rao,Tantravahi Venkata Ramana. |
| Field-based soil moisture measurements are cumbersome. Thus, remote sensing techniques are needed because allows field and landscape-scale mapping of soil moisture depth-averaged through the root zone of existing vegetation. The objective of the study was to evaluate the accuracy of an empirical relationship to calculate soil moisture from remote sensing data of irrigated soils of the Apodi Plateau, in the Brazilian semiarid region. The empirical relationship had previously been tested for irrigated soils in Mexico, Egypt, and Pakistan, with promising results. In this study, the relationship was evaluated from experimental data collected from a cotton field. The experiment was carried out in an area of 5 ha with irrigated cotton. The energy balance and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Standard relationship; SEBAL; Energy balance; Evaporative fraction; Latent heat flux. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832013000300005 |
| |
|
| |
| Registros recuperados: 35 | |
|
|
|
