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| Registros recuperados: 101 | |
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| Deroine, Morgan; Le Duigou, Antoine; Corre, Yves-marie; Le Gac, Pierre-yves; Davies, Peter; Cesar, Guy; Bruzaud, Stephane. |
| Pollution of nature by plastics is a major environmental problem and the challenge for the future is to manage the lifetime of polymers better. The aim of this study is to establish a baseline on degradation mechanism and degradation kinetics for lifetime prediction of polylactide (PLA) in a marine environment. The ageing of PLA was accelerated by raising temperature in distilled water, filtered and renewed seawater and natural seawater. Samples were immersed in distilled water for six months at different temperatures (25, 30, 40 and 50°C) in order to evaluate the influence of temperature on PLA degradation kinetics and to predict lifetime. Then, samples were immersed in seawater both in the laboratory and at sea, in order to compare the effects of... |
| Tipo: Text |
Palavras-chave: PLA; Accelerated ageing; Hydrothermal ageing; Degradation. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00173/28376/26689.pdf |
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| Le Gac, Pierre-yves; Le Saux, V.; Paris, M; Marco, Y.. |
| Polymers are widely used in marine environments due to their excellent properties and good weathering resistance. Despite this extensive use, their long term behaviour in such an aggressive environment is still not well known. To assess the polymer durability within reasonable durations, it is essential to perform accelerated ageing tests to accelerate the degradation kinetics but without any modification of the degradation process. This study therefore proposes and validates accelerated ageing tests to study marine ageing of a silica-filled chloroprene rubber (CR) used for offshore applications. Several accelerated ageing protocols are investigated for temperatures ranging from 20 to 80 degrees C in renewed natural seawater. The ageing consequences are... |
| Tipo: Text |
Palavras-chave: Chloroprene rubber; Degradation; Sea water; Silica; Accelerated ageing; Natural ageing. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00073/18429/20232.pdf |
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| Moraes,Fillipe Alexandre; Takeda,Othavio Toniasso. |
| ABSTRACT The growing use of Photovoltaic Solar Energy in Brazil, both in power plants and in distributed generation systems, brings with it a series of practical and technical questions that are not limited to the design and project of the systems. Environmental factors and resources related to the use, operation, maintenance, decommissioning and final disposal of the equipment and components that constitute them, should be taken into consideration, so that these systems maintain an adequate performance during their lifespan granting the safety for users, properties and avoid negative environmental impacts. Within the concept of Risk Analysis within the Life Cycle of these systems, the present study addresses a perspective of the growth of the use of Solar... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Photovoltaic Installations; Maintenance; Degradation; Reliability. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132018000200234 |
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| Zheng, Zhou; Jin, Qing; Miao, Jinlai; Liu, Fangming. |
| Two hydrocarbon degrading bacteria NJ276 and NJ341 were screened from 385 Antarctic marine bacteria and their degrading characteristics were studied. Diesel oil as sole carbon source was used in this study. The results showed that the oil degradation rates of Antarctic psychrophile bacteria NJ276 and NJ341 were 23.47 % and 32.15 %, respectively, after 20 days culturation at 5 °C, and the rates were 43.95 % and 62.47 % respectively after 20 days culturation at 15 °C. The oil degradation abilities were enhanced remarkably with the increasing culture temperature. GC - MSs indicated the residual oil contained C15 - C21 7 alkyls after degradation by NJ276, and C16, C17 and C18 3 alkyls after degradation by NJ341. The 16S rDNA gene sequences homology and... |
| Tipo: Journal Contribution |
Palavras-chave: Hydrocarbons; Degradation; Bacteria. |
| Ano: 2008 |
URL: http://hdl.handle.net/1834/5879 |
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| Olivo, Paula Martins; Santos, Geraldo Tadeu dos; Ítavo, Luís Carlos Vinhas; Silva Junior, Ranulfo Combuca da; Leal, Eduardo Souza; Prado, Rodolpho Martin do. |
| Agroindustrial co-products are a viable alternative for use in animal nutrition. Tests were conducted using eight different types of co-products and feed to evaluate the chemical composition, in vitro digestibility of dry matter, crude protein and neutral detergent fiber, and gas production by them. The co-products tested were: coffee hulls; pelleted citrus pulp; grape residue; soybean hulls; cottonseed; cassava foliage; and foods usually supplied to ruminants: corn silage and ground corn concentrate. Data of in vitro digestibility of dry matter, crude protein and neutral detergent fiber were tested by analysis of variance using the least square method; the results of gas production were interpreted by a non-linear regression by the Gauss-Newton method;... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Zootecnia; Nutrição de Ruminantes alternative feed; Degradation; Fermentation; Gas production.s. |
| Ano: 2017 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/34024 |
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| Gonçalves,Morgana S.; Sampaio,Silvio C.; Coelho,Silvia R. M.; Suszek,Floriano L.; Cordovil,Claudia M. D. S.. |
| The effects of swine wastewater on atrazine dissipation and formation of bound residues in subtropical clay soil were investigated in this study. The experiment was carried out in laboratory, under room conditions, where samples of Rhodic Hapludox soil received 168.61 mg kg-1 of atrazine and were incubated for 60 days in the following treatments: T1 (sterilized soil + swine wastewater), T2 (sterilized soil + distilled water), T3 (Non sterilized soil + swine wastewater) and T4 (Non sterilized soil + distilled water). The extractable residues and bound residues of atrazine were extracted and analyzed by high performance liquid chromatography. The results showed no effect of swine wastewater on atrazine dissipation. However, the addition of swine wastewater... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicide; Degradation; Sorption; Organic matter. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000600017 |
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| Tallur,Preeti N.; Mulla,Sikandar I.; Megadi,Veena B.; Talwar,Manjunatha P.; Ninnekar,Harichandra Z.. |
| Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Degradation; Immobilization; Cypermethrin; Polyurethane foam; Micrococcus sp. strain CPN 1. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000300667 |
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| Martínez, S.; Acosta, A.. |
| Several predictions have been made, about magnitude and direction of temporal changes in the coral community structure, during the last decade. However, few studies have demonstrated it quantitatively. In order to document such changes, the coral community structure was studied in four continental reefs in the Colombian Caribbean, two in the Santa Marta region: Punta Betín (PB) and Morro Grande Island (MO), and two in the Tayrona National Natural Park (PNNT): Granate cove (GR) and Gayraca bay (GA). Coral composition and cover were quantified in 2002 and compared to base line studies from 1989 (PB, MO & GR) and from 1992 (GA). These variables were quantified by 20 m linear transects between 1.5 m and 29 m depth. After a decade, all reefs lost in average... |
| Tipo: Journal Contribution |
Palavras-chave: Coral reefs; Degradation; Temporal variations; Community composition; Coral reefs; Degradation; Http://aims.fao.org/aos/agrovoc/c_1880; Http://aims.fao.org/aos/agrovoc/c_2159. |
| Ano: 2005 |
URL: http://hdl.handle.net/1834/2012 |
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| Pablo Pérez, Maricela. |
| El objetivo del presente estudio fue conocer el potencial nutricional para la alimentación animal de cinco especies de Lupinus (L. montanus, L. exaltatus, L. campestris, L. hintonii, y Lupinus sp.). Plantas completas en floración (componente follaje) y fructificación (componentes: vainas y semillas) fueron recolectadas en la Región de Valles y Libres del Serdán, Puebla, durante julio y agosto de 2010, a una altitud entre 2486 y 3442 m. Los análisis realizados por componente fueron proteína cruda (PC), extracto etéreo (EE), cenizas (Ce), fibra detergente neutro (FDN), fibra detergente ácido (FDA), alcaloides totales (Alc), polifenoles totales (Pt), taninos condensados (Tc), degradación in situ de MS, MO, PC, FDN y FDA, composición mineral de semillas y su... |
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Palavras-chave: Lupinus; Leguminosa; Silvestre; Valor nutritivo; Composición química; Degradación; Legumes; Wild; Nutritive value; Chemical composition; Degradation; Producción Agroalimentaria en el Trópico; Maestría. |
| Ano: 2013 |
URL: http://hdl.handle.net/10521/1869 |
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| Li, J.; Vincx, M.; Herman, P.M.J.. |
| A time dynamic model was used to estimate carbon flows through nematodes in an intertidal benthic ecosystem in the Westerschelde Estuary, The Netherlands. The model calibrated the nematode biomass observed from March 1991 to February 1992. The forcing functions of the model included meiobenthos biomass, macrobenthos biomass, bacterial density, chlorophyll-a concentration, and other abiotic data such as temperature and day length. We estimate that the nematode population had a low level of standing stock 249 mg C m(-2), but a high level of carbon flow. It consumed 98 mg C m(-2) d(-1) and produced 22 mg C m(-2) d(-1). Defecation was 73 mg C m(-2) d(-1). Losses in respiration, excretion and natural death were only 3 mg C m(-2) d(-1). The annual P/B was 32 for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Degradation; Ecology; Marine nematodes; Meiobenthos; Respiration. |
| Ano: 1997 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=7296 |
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| Bundt,A.D.C.; Avila,L.A.; Agostinetto,D.; Nohatto,M.A.; Vargas,H.C.. |
| Herbicides used in Clearfield(r) rice system may persist in the environment, damaging non-tolerant crops sown in succession and/or rotation. These damages vary according to soil characteristics, climate and soil management. The thickness of the soil profile may affect carryover effect; deeper soils may allow these molecules to leach, reaching areas below the roots absorption zone. The aim of this study was to evaluate the effect of the thickness of soil profile in the carryover of imazethapyr + imazapic on ryegrass and non-tolerant rice, sown in succession and rotation to rice, respectively. Lysimeters of different thicknesses (15, 20, 30, 40, 50 and 65 cm) were constructed, where 1 L ha-1 of the imazethapyr + imazapic formulated mixture was applied in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Degradation; Imidazolinone; Lolium multiflorum; Leaching; Oryza sativa. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582015000200357 |
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| Carvalho, Francisco Allan Leandro de; Resende, Percivaldo Xavier; Benicio, Clístenes Amorim; Siqueira, Jackson de Oliveira; Menezes, Daniel Ribeiro; Queiroz, Mário Adriano Ávila. |
| The objective this study was to evaluate the effect of maniçoba supplementation in sugar cane silage with respect to chemical-bromatological composition and the in vitro degradation kinetics of the silage. This experiment was conducted in a completely randomized design with four treatments (maniçoba levels: 0, 20, 30, and 40%) and six repetitions. Silage samples were analyzed for their chemical-bromatological composition, digestible energy, metabolizable energy, total digestible nutrients, in vitro gas production and degradability parameters. The silage with higher inclusion level had better bromatological composition (p < 0.05) than the silage without maniçoba for CP, NDF, ADF and MM (6.49, 56.64, 38.66 and 4.52% versus 2.21, 70.96, 49.95 and 2.78%).... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Degradation; Forage conservation; Gas production; Saccharum officinarum.. |
| Ano: 2018 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/42569 |
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| SCORZA JUNIOR, R. P.; RIGITANO, R. L. de O.; FRANCO, A. A.. |
| Informações sobre o comportamento de pesticidas são importantes para o conhecimento do seu destino ambiental e, consequentemente, para a avaliação da sustentabilidade dos sistemas de produção agrícolas. Este trabalho teve os seguintes objetivos: (i) quantificar a lixiviação de dois inseticidas (endossulfam e tiametoxam) em uma área de plantio de soja na região de Ponta Porã, MS; (ii) avaliar a degradação e sorção dos dois inseticidas no solo em estudo; e (iii) testar e calibrar os simuladores MACRO e PEARL para descrever os dados observados da lixiviação dos dois inseticidas nas condições consideradas. Amostras de solo para quantificação da lixiviação dos pesticidas foram coletadas nas profundidades de 0-10 cm, 10-30 cm, 30-50 cm, 50-70 cm e 70-100 cm aos... |
| Tipo: Folhetos |
Palavras-chave: Degradação do solo; Lixiviação; Degradation; Leaching; Soil. |
| Ano: 2010 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/880300 |
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| OLIVEIRA, E. L. de; RODRIGUES, G. de S.; SANTIAGO, L. B.; SOUZA, H. A. de. |
| A compostagem se enquadra no processo biológico de reciclagem de nutrientes e surge como uma alternativa viável por reduzir o peso e o volume dos resíduos gerados. A compostagem é uma técnica de decomposição e sanitização da matéria orgânica à alta temperatura, pela ação de bactérias e fungos que transformam as carcaças em um produto útil, denominado de composto orgânico. Essa técnica é acessível ao produtor rural e as agroindústrias, tais como frigoríficos e abatedouros. O composto orgânico é um adubo que pode ser utilizado em áreas agrícolas, conforme Instrução Normativa nº 25 de 2009 do Ministério da Agricultura, Pecuária e Abastecimento, que trata da produção e do uso de compostos orgânicos. O uso de composto orgânico apresenta as vantagens de reduzir... |
| Tipo: Folhetos |
Palavras-chave: Resíduo de carcaça; Carcass utilization; Carcasses; Waste; Composto orgânico; Compostagem; Matéria orgânica; Decomposição; Manejo; Caprino; Ovino; Organic compounds; Composting; Organic matter; Degradation; Goats; Sheep. |
| Ano: 2015 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1019361 |
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| Whitby, Hannah; Bressac, Matthieu; Sarthou, Geraldine; Ellwood, Michael J.; Guieu, Cécile; Boyd, Philip W.. |
| Iron is a key micronutrient in seawater, but concentrations would be negligible without the presence of organic ligands. The processes influencing the ligand pool composition are poorly constrained, limiting our understanding of the controls on dissolved iron distributions. To address this, the release of iron and iron‐binding ligands during the microbial remineralisation of sinking particles was investigated by deploying in situ particle interceptor/incubator devices at subsurface sites in the Mediterranean Sea and Subantarctic. Analyses revealed the pool of released ligands was largely dominated by electroactive humic substances (74 ± 28%). The release of ligands during remineralisation ensured that concurrently released iron remained in solution, which... |
| Tipo: Text |
Palavras-chave: Iron; Ligand; Humic; Remineralisation; Particle; Degradation. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00618/72981/72055.pdf |
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| Registros recuperados: 101 | |
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