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| Registros recuperados: 27 | |
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| Yrene M,Astor; Scranton,Mary; Guzmán,Laurencia; Thunell,Robert; Muller-Karger,Frank; Taylor,Gordon; Fanning,Kent; Varela,Ramón. |
| For more than ten years, the CARIACO Time-Series Program has studied seasonal patterns and interannual variability at the Cariaco Basin. Monthly core physical and biogeochemical observations have been collected since November 1995 at the CARIACO Time-Series station (10º 30' N, 64º 40' W). A region with suboxic conditions (oxygen and sulfide concentrations <1 µM) is found at intermediate waters at the station. The characteristics of this region show time and space variability, depending on the dynamics of the water. In general, ammonium, nitrate and nitrite disappeared within the suboxic region, although there is a steep ammonium concentration increase with depth after the oxic-anoxic interface suggesting its consumption at this boundary. Our data shows... |
| Tipo: Journal article |
Palavras-chave: Oxic-anoxic interface; Ventilation; Cariaco basin; Intrusions. |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382006000300002 |
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| Macgilchrist, Graeme A.; Marshall, David P.; Johnson, Helen L.; Lique, Camille; Thomas, Matthew. |
| Ventilation of the upper ocean plays an important role in climate variability on interannual to decadal timescales by influencing the exchange of heat and carbon dioxide between the atmosphere and ocean. The turbulent nature of ocean circulation, manifest in a vigorous mesoscale eddy field, means that pathways of ventilation, once thought to be quasi-laminar, are in fact highly chaotic. We characterize the chaotic nature of ventilation pathways according to a nondimensional filamentation number, which estimates the reduction in filament width of a ventilated fluid parcel due to mesoscale strain. In the subtropical North Atlantic of an eddy-permitting ocean model, the filamentation number is large everywhere across three upper ocean density... |
| Tipo: Text |
Palavras-chave: Ventilation; North Atlantic; Thermocline; Chaos; Mesoscale eddies; Lagrangian trajectories. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00410/52104/52807.pdf |
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| Ronge, Thomas A.; Prange, M.; Mollenhauer, Gesine; Ellinghausen, Maret; Kuhn, G.; Tiedemann, R.. |
| It is widely assumed that the ventilation of the Southern Ocean played a crucial role in driving glacial‐interglacial atmospheric CO2‐levels. So far however, ventilation records from the Indian sector of the Southern Ocean, are widely missing. Here we present reconstructions of water residence times (depicted as ΔΔ14C and Δδ13C) for the last 32,000 years on sediment records from the Kerguelen Plateau and the Conrad Rise (~570‐2500 m water depth), along with simulated changes in ocean stratification from a transient climate model experiment. Our data indicate that Circumpolar Deep Waters in the Indian Ocean were part of the glacial carbon pool. At our sites, close to or bathed by upwelling deep‐waters, we find two pulses of decreasing ΔΔ14C and δ13C values... |
| Tipo: Text |
Palavras-chave: Radiocarbon; Ventilation; Southern Ocean; Younger Dryas; Carbon cycle; Indian Ocean. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00611/72351/71258.pdf |
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| Ohkushi, K.; Kennett, J. P.; Zeleski, C. M.; Moffitt, S. E.; Hill, T. M.; Robert, Cyril; Beaufort, L.; Behl, R. J.. |
| The oxygen minimum zone (OMZ) of the late Quaternary California margin experienced abrupt and dramatic changes in strength and depth in response to changes in intermediate water ventilation, ocean productivity, and climate at orbital through millennial time scales. Expansion and contraction of the OMZ is exhibited at high temporal resolution (107-126 year) by quantitative benthic foraminiferal assemblage changes in two piston cores forming a vertical profile in Santa Barbara Basin (569 m, basin floor; 481 m, near sill depth) to 34 and 24 ka, respectively. Variation in the OMZ is quantified by new benthic foraminiferal groupings and new dissolved oxygen index based on documented relations between species and water-mass oxygen concentrations.... |
| Tipo: Text |
Palavras-chave: Oxygen minimum zone; Foraminifera; Ventilation; Oxygen index; Pacific; Hypoxia. |
| Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00264/37489/35811.pdf |
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| Ronge, Thomas Alexander. |
| Reconstructions on Antarctic ice cores revealed pronounced, millennial-scale variabilities in atmospheric CO2 over the past 800,000 years (e.g. Lüthi et al., 2008; Monnin et al., 2001; Petit et al., 1999; Raynaud et al., 2005; Siegenthaler et al., 2005). Despite these variabilities are known for several decades, the mechanisms, driving these patterns are still not fully resolved. As the ocean contains up to 60 times more carbon than the entire atmosphere, it is considered to be a major driver of the atmospheric CO2 levels (Broecker, 1982): Storing CO2 during glacials, releasing it during deglaciations. Because changes in the global thermohaline circulation are thought to operate on glacial/interglacial timescales, it has been suggested that during... |
| Tipo: Text |
Palavras-chave: 14C; Ventilation; Atmospheric CO2; AAIW; UCDW; LCDW; AABW. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00493/60453/63898.pdf |
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| Skinner, L. C.; Freeman, E.; Hodell, D.; Waelbroeck, C.; Vazquez Riveiros, Natalia; Scrivner, A.e. |
| Changes in ocean ventilation, controlled by both overturning rates and air‐sea gas exchange, are thought to have played a central role in atmospheric CO2 rise across the last deglaciation. Here we constrain the nature of Atlantic Ocean ventilation changes over the last deglaciation using radiocarbon and stable carbon isotopes from two depth transects in the Atlantic basin. Our findings broadly cohere with the established pattern of deglacial Atlantic overturning change, and underline the existence of active northern sourced deep‐water export at the Last Glacial Maximum (LGM). We find that the western Atlantic was less affected by incursions of southern‐sourced deep water, as compared to the eastern Atlantic, despite both sides of the basin being strongly... |
| Tipo: Text |
Palavras-chave: Air‐ Sea exchange; AMOC; Carbon cycle; Deglaciation; Radiocarbon; Ventilation. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00665/77717/79810.pdf |
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| Durand, Axel; Chase, Zanna; Noble, Taryn L.; Bostock, Helen; Jaccard, Samuel L.; Townsend, Ashley T.; Bindoff, Nathaniel L.; Neil, Helen; Jacobsen, Geraldine. |
| To investigate changes in oxygenation at intermediate depths in the southwest Pacific between the Last Glacial Maximum (LGM) and the Holocene, redox sensitive elements uranium and rhenium were measured in 12 sediment cores located on the Campbell and Challenger plateaux offshore from New Zealand. The core sites are currently bathed by Subantarctic Mode Water (SAMW), Antarctic Intermediate Water (AAIW) and Upper Circumpolar Deep Water (UCDW). The sedimentary distributions of authigenic uranium and rhenium reveal reduced oxygen content at intermediate depths (800-1500 m) during the LGM compared to the Holocene. In contrast, data from deeper waters (>= 1500 m) indicate higher oxygen content during the LGM compared to the Holocene. These data, together with... |
| Tipo: Text |
Palavras-chave: Oceanic deoxygenation; Redox sensitive elements; Ventilation; Antarctic Intermediate Water; New Zealand; Circulation changes. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00495/60703/83612.pdf |
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| Camargo,Tiago F. B.; Silva,Robson L.; Higa,Márcio; Coutinho,Mônica R.; Oliveira,Júlio C. D. de; Conceição,Wagner A. dos S.. |
| ABSTRACT Thermal comfort inside broiler husbandry facilities is essential in obtaining good results in the production activity. Assessment of adequate thermodynamic conditions requires measurement and control, usually implying costs and specialized maintenance. The objective of this research was to monitor the temperature, relative humidity and air speed distributions by a developed low-cost, open-source and easy-to-use measurement system, using Arduino (hardware) and Scilab (software) for real-time data acquisition. Sensors were installed in a real facility (Cianorte, PR), with measurements for internal ambient (20 sensors for temperature/relative humidity, and two sensors for differential pressure, respectively 0.5 and 1.5 m high) and external ambient... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Measuring system; Ventilation; Computational fluid dynamics; Poultry production. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000900694 |
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| Sartor,Valmir; Baêta,Fernando da Costa; Tinôco,Ilda de Fátima Ferreira; Luz,Maira Luciana. |
| The thermal environment inside of a finishing phase swine barn has great influence on the success of swine production. This environment can be characterized by the black globe temperature and humidity index (BGHI), that represents the air temperature, humidity, wind speed and radiation. Due to the small number of Brazilian reports on this specific subject, this experiment was performed to verify the effect of one kind of evaporative cooling system on the thermal comfort of the animal in a swine barn, during the 98/99 summer at Patos de Minas, MG, Brazil. Two constructions were used, divided in 36 barns, each one with 15 animals, 110 to 150 days old. Along a side of one barn, four cooling devices were installed, with a ventilation system connected to a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ventilation; Thermal environment; Thermal comfort. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000100003 |
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| Ndirangu, Samuel Njuguna. |
| Solar drying systems are not able to achieve best drying rates given the intermittent nature of solar energy and poor airflows. To address this problem, a solar-biomass dryer measuring 8 m long, 4 m wide and 2.6 m high, with two layers of beds, was developed for use by medium scale processors in Kenya. It had a bimodal biomass heating system to back up the solar energy, and four provisions for air ventilation; chimney, turbo ventilators, lower opening and fans. It was constructed and preliminary tests on it undertaken at Khwisero in Kakamega County, Kenya. Six commonly grown crops; arrow roots (Maranta arundinacea), cassava (Manihot esculenta), sweet potatoes (Ipomoea batatas), kales (Brassica oleraceae var acephala), bananas (Musa spp.) and spider plant... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Solar-biomass; Greenhouse dryer; Ventilation; Performance. |
| Ano: 2020 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5644 |
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| Arcidiacono, Claudia. |
| Heat stress in animal housing is one of the drivers affecting animal productivity and welfare in hot climates, and causing consequent reduced profits for the farmers. The main challenges that livestock breeding faces in hot climates regards how to foster, improve, and assess methods and strategies for animal heat stress abatement. Research studies in this field have generally proposed modifications in herd management and in feeding strategies, breed selection, and engineered solutions aimed at exploiting heat transmission phenomena. In this paper, the most recent engineered solutions for animal heat stress abatement in livestock buildings have been reviewed and described; they have involved new building and ventilation design and modelling, and improved... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rural buildings livestock buildings; Design; Modelling; Ventilation; Hot climate. |
| Ano: 2018 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/4705 |
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| Kic, Pavel. |
| This paper is focused on the Computational fluid dynamics (CFD) modeling of regenerative heat exchanger suitable for animal houses. Buildings used for housing of animals in farms with intensive breeding, like poultry or pig houses, are characterized by high generation of heat inside, partly produced by animals, and in the case of small young animals, supplemented also by heating. On the other side these buildings need intensive ventilation which causes big losses of energy by exhausted air. A good way how to reduce heat losses can be the use of technical systems of heat recovery. There are two principal constructions of heat exchangers for heat recovery. There are either recuperative or regenerative heat exchangers. Industrially produced heat exchangers,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal houses; Ventilation; Energy; Parameters; Czech Republic. |
| Ano: 2015 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3137 |
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| Tabase, Raphael Kubeba. |
| The study aims to develop a test platform (TP) compartment that could mimic diurnal variations in indoor climate and NH3 emission in a real pig compartment and to compare diurnal indoor climate and NH3 production between two TP compartments and a real compartment. The objectives were achieved by using a real and TP compartment followed by an ad hoc test that used two TP compartments and another real compartment. The TP had two compartments equipped with mock-up pigs as heat source and automatic urea solution spraying installation to mimic pig urination at the pen floor. The study evaluated indoor climate and NH3 production in a 4-day comparative test between a TP and a real compartment followed by a 3-day comparative test between two TP compartments and a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ammonia; Emission; Modeling; Pig housing; Test platform; Ventilation; Belgium. |
| Ano: 2019 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5216 |
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| Pavel Kic. |
| This paper is focused on the Computational fluid dynamics (CFD) modeling of regenerative heat exchanger suitable for animal houses. Buildings used for housing of animals in farms with intensive breeding, like poultry or pig houses, are characterized by high generation of heat inside, partly produced by animals, and in the case of small young animals, supplemented also by heating. On the other side these buildings need intensive ventilation which causes big losses of energy by exhausted air. A good way how to reduce heat losses can be the use of technical systems of heat recovery. There are two principal constructions of heat exchangers for heat recovery. There are either recuperative or regenerative heat exchangers. Industrially produced heat exchangers,... |
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Palavras-chave: Animal houses; Ventilation; Energy; Parameters; Czech Republic. |
| Ano: 2015 |
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3137 |
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| Jaramillo,C.; Gutierrez,M.P. Arias. |
| ABSTRACT To determine the prevalence of diseases of the upper respiratory tract and associated factors in the Colombian Creole Horse Valley Aburrá in 2015, a random sampling of 15 farms in southern Aburrá Valley under different management conditions was performed. A total of 105 CCC underwent general clinical examination, respiratory endoscopic evaluation and a detailed inspection of housing conditions and management. A low prevalence of upper respiratory tract diseases was observed, including Pharyngeal Lymphoid Hyperplasia 38.1%, Recurrent Laryngeal Neurophaty 12.38%, Dorsal Displacement of the Soft Palate 7.62%, and presence of tracheal secretions not associated with a specific pathology. A bivariate analysis showed association between tracheal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Equine; Respiratory diseases; Handling; Ventilation. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352018000200333 |
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| Horr,M.; Nunes,N.; Biteli,E.G.F.; Lopes,P.C.F.; Gering,A.P.; Moro,J.V.; Rocha,F.D.L.. |
| ABSTRACT It is important to identify the best inspired fraction of oxygen in a variety of situations, including sevoflurane or isoflurane anesthesia, in spontaneously breathing rabbits. For this, 64 rabbits were assigned to eight groups: GI100 (FiO2= 1,0 + isoflurane), GS100 (FiO2= 1,0 + sevoflurane), GI80 (FiO2= 0,8 + isoflurane), GS80 (FiO2= 0,8 + sevoflurane), GI60 (FiO2= 0,6 + isoflurane), GS60 (FiO2= 0,6 + sevoflurane), GI21 (FiO2= 0,21 + isoflurane), GS21 (FiO2= 0,21 + sevoflurane). The induction was performed with (2.5MAC) of the anesthetic. The vaporizer was setted at 1.5 MAC and FiO2 as attributed for each group. After the induction, the concentration was changed to 1 MAC. Measurements of parameters were performed 30 minutes after induction (T0),... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rabbit; Inhalatory anesthesia; Ventilation. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352019000300944 |
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| TEIXEIRA,Maria Araújo; CHAGURI,Luziane do Carmo Andrade Guinski; CARISSIMI,André Silva; SOUZA,Nívea Lopes de; MORI,Claudia Madalena Cabrera; GOMES,Valéria Maria Wanderley; POLI NETO,Adelino; NONOYAMA,Kimiyo; MERUSSE,José Luiz Bernardino. |
| Previous studies reported that rats (Rattus norvegicus) kept under microenvironmental ventilation systems (MEV) present better productive and health parameters when compared to animals kept under general diluting ventilation (GDV). The objective of the present research trial was to evaluate hematological and biochemical profiles of rats kept under MVS. In order to achieve this objective, two different trials were designed: Trail 1 (E1), in which it was evaluated the reproductive performance of males and females submitted to two different air speed limits - FV1, from 0.03 to 0.26 m / sec and FV2, from 0.27 to 0.80 m / sec. In Trial 2 (E2) it was evaluated different bed change intervals (3, 5, 7 and 9 days), for males kept under constant air speed (0.5 m /... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Laboratory animals; Rats; Hematology; Biochemistry; Ventilation. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-95962000000500001 |
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| Registros recuperados: 27 | |
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