|
|
|
| Registros recuperados: 48 | |
|
|
| CORREIA,LÍVIA O.; SIQUEIRA JÚNIOR,SÉRGIO; CARNEIRO,PAULO L.S.; BEZERRA,MARCOS A.. |
| This paper presents a study on the viability of the use of tissues of the Leptodactylus ocellatus species (Anura Leptodactylidae) as a bioindicator of metal pollution. The study is based on the determination and correlation of the concentrations of manganese, chromium, zinc, nickel, copper and iron in sediments and tissues (skin, muscles and viscera) of the frog Leptodactylus ocellatus collected in the middle region of the Contas River in Bahia, Brazil. The highest levels of the metals studied were found in the viscera of this animal. In this tissue, a higher correlation of the concentration of these metals with those found in sediments was also observed. The concentrations of elements found in the skin and muscles of these amphibians have revealed no... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Leptodactylus ocellatus; Bioindicators; Sediments; Metals; Contas River. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000401549 |
| |
|
|
| CAMPANER,VERIDIANA P.; LUIZ-SILVA,WANILSON; MACHADO,WILSON. |
| Acid drainage influence on the water and sediment quality was investigated in a coal mining area (southern Brazil). Mine drainage showed pH between 3.2 and 4.6 and elevated concentrations of sulfate, As and metals, of which, Fe, Mn and Zn exceeded the limits for the emission of effluents stated in the Brazilian legislation. Arsenic also exceeded the limit, but only slightly. Groundwater monitoring wells from active mines and tailings piles showed pH interval and chemical concentrations similar to those of mine drainage. However, the river and ground water samples of municipal public water supplies revealed a pH range from 7.2 to 7.5 and low chemical concentrations, although Cd concentration slightly exceeded the limit adopted by Brazilian legislation for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Acid mine drainage; Coal; Metals; Water quality. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000200539 |
| |
|
| |
|
| |
|
|
| BARROS,JOÉLIA M.; BEZERRA,MARCOS A.; VALASQUES,GISSELI S.; NASCIMENTO JÚNIOR,BARAQUÍZIO B. DO; SOUZA,ANDERSON S.; ARAGÃO,NÁDIA M. DE. |
| In this work, multivariate optimization techniques were used to develop a method based on the ultrasound-assisted extraction for copper, manganese, nickel and zinc determination from rations for chicken nutrition using flame atomic absorption spectrometry. The proportions of extracting components (2.0 mol.L–1 nitric, hydrochloric and acetic acid solutions) were optimized using centroid-simplex mixture design. The optimum proportions of this mixture taken as percentage of each component were respectively 20%, 37% and 43%. Variables of method (sample mass, sonication time and final acid concentration) were optimized using Doehlert design. The optimum values found for these variables were respectively 0.24 g, 18s and 3.6 mol.L–1. The developed method allows... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rations to chicken; Ultrasound-assisted extraction; Mixture design; Doehlert design; Metals. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000300891 |
| |
|
|
| Teixeira,Elba C.; Migliavacca,Daniela; Pereira Filho,Sadi; Machado,Andréa C.M.; Dallarosa,Juliana B.. |
| The purpose of this study is to analyze the chemical composition of wet precipitation in samples collected at three stations in the Candiota region in the Brazilian state of Rio Grande do Sul (RS). Samples were collected in 2004. Variables analyzed in wet precipitation were pH, conductivity, and concentration of Cl-, NO3-, SO4(2-) F-, Na+, Ca2+, Mg2+, K+, NH4+, Cu, Zn, Fe, Mn, Pb, Ni, Cd, Co, and Cr. SO2 and NO2 distribution over the time were also evaluated. Results have showed that pH < 5.6 are found mostly at Candiota airport (85%), followed by Aceguá (72%) and Três Lagoas (65%). Enrichment Factor of the studied ions in wet deposition revealed higher Ca2+ and SO4(2-) enrichment in Três Lagoas. Factor Analysis applied to metals and major ions allowed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Wet precipitation; Metals; Factor analysis. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652008000200016 |
| |
|
|
| BOKOWSKI,LIANE V.V.; SOBRINHO,ROBERTO B.; ARMIJO,CRISTIÁN J.V.; DANI,CAROLINE; HENRIQUES,JOÃO A.P.; FUNCHAL,CLÁUDIA. |
| ABSTRACT Vitis labrusca L. is the main species used for wine and juice production in Brazil. The grapevine leaves can be used both as functional foods and as cheapest sources for the extraction of phenolic compounds. Besides the antioxidant activity, grapevine leaves exhibited significant anti-inflammatory activity. Therefore, the aim of this study was to develop and validate an analytical methodology to determine the metals selenium (96Se), chromium (53Cr), nickel (62Ni), cadmium (111Cd) and lead (206Pb) in 30 samples of grapevine leaf extracts (Vitis labrusca, Bordo cultivar) using inductively coupled plasma mass spectrometry (ICP-MS). To obtain the grapevine leaf extracts the samples were milled, weighed and digested in microwave oven with nitric acid.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: ICP-MS; Metals; Method validation; Vitis labrusca L. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000602247 |
| |
|
|
| PEREIRA,CLÁUDIA A.F.; MAIA,LUIZ F.O.; FARIA,MÁRCIA C.S.; FIDÊNCIO,PAULO H.; BOMFETI,CLEIDE A.; BARBOSA JUNIOR,FERNANDO; RODRIGUES,JAIRO L.. |
| Abstract In aquatic habitats, metal contamination from natural and anthropogenic sources continues to pose a concern for human and environmental health. Thus, it is important to complete monitoring studies to assess patterns and the extent of metal contamination in these ecosystems. The purpose of this work was to determine the concentrations of 31 chemical elements and water quality parameters of the Todos os Santos River located in the Mucuri Valley, Minas Gerais, Brazil. A multivariate statistical analysis was used to determine any seasonal and spatial patterns from the data. Results demonstrated that metals including Al, Fe, and Ni exceeded Brazilian and international guidelines nutrients as P also exceed water quality standards. Principal components... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Toxic pollutants; Metals; Water quality; Environment. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000602701 |
| |
|
|
| SCHNEIDER,ISMAEL L.; TEIXEIRA,ELBA C.; RODRIGUES,MARIA LUCIA K.; ROLIM,SILVIA B.A.. |
| The present study aimed to evaluate Cu, Cr, Ni, Zn, Pb, Mn, Al, and Fe contents, as well as their geochemical partitioning in Sinos River basin sediments in southern Brazil. This basin is a densely populated area with a substantial number of industries, especially metallurgy, electroplating works, steel mills, petrochemicals, and tanneries. The total metal concentrations were determined by X-ray fluorescence and the sediment phase concentrations were determined by applying the BCR-701 sequential extraction method proposed by the Community Bureau of Reference of the European Community, using ICP/OES. The contents extracted by a solution of 0.5 mol/L HCl were also considered. Metal contents were evaluated in the sediment fraction <63 µm. Results in the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: BCR-701; Metals; Sediment; Sequential extraction. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000301043 |
| |
|
|
| ARREDONDO,MIGUEL; MARTÍNEZ,RONNY; NÚÑEZ,MARCO T; RUZ,MANUEL; OLIVARES,MANUEL. |
| Interactions of micronutrients can affect absorption and bioavailability of other nutrients by a number of mechanisms. In aqueous solutions, and at higher uptake levels, competition between elements with similar chemical characteristics and uptake process can take place. The consequences of these interactions may depend on the relative concentrations of the nutrients. In this work, we measure the effects of increasing concentrations of iron, zinc, and copper on iron and copper uptake in Caco-2 cells. Intracellular Fe or Cu levels were affected by incubating with increased concentrations of metals. However, when the cells already had different intracellular metal concentration, the uptake of Fe or Cu was nor affected. In competition studies, we showed that... |
| Tipo: Journal article |
Palavras-chave: Competition; Interaction; Metals; Uptake. |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100011 |
| |
|
|
| Yamanaka,Renata; Soares,Clarissa F.; Matheus,Dácio R.; Machado,Kátia M.G.. |
| The expression of the enzymatic system produced by basidiomycetous fungi, which is involved in the degradation of xenobiotics, mainly depends on culture conditions, especially of the culture medium composition. Trametes villosa is a strain with a proven biotechnological potential for the degradation of organochlorine compounds and for the decolorization of textile dyes. The influence of glucose concentration, addition of a vegetable oil-surfactant emulsion, nature of the surfactant and the presence of manganese and copper on the growth, pH and production of laccase, total peroxidase and manganese-dependent peroxidase activities were evaluated. In general, acidification of the medium was observed, with the pH reaching a value close to 3.5 within the first... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Laccase; Metals; MnP; Vegetable oil; Surfactants. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822008000100019 |
| |
|
|
| Bernini,Elaine; Silva,Maria A. B. da; Carmo,Tania M. S. do; Cuzzuol,Geraldo R. F.. |
| Spatial and temporal variation of the nutrient concentrations in leaves and sediment between the roots of Laguncularia racemosa (L.) Gaertn. f and Rhizophora mangle L. was analyzed in the mangrove forest of the estuary of São Mateus River, Espírito Santo, Brazil. In leaves, the nutrients followed the sequence: N> Ca> K> Mg> S> P> Fe> Mn> Zn> Cu, and there were significant differences between species and sites studied. In general, the levels of K were higher in the dry season compared to the rainy season for both species analyzed while Ca and Cu showed higher concentrations in the rainy season for Laguncularia racemosa. In the sediment, the nutrients followed the sequence: Mg> Ca> Fe> K> Mn> P> Zn> Cu, in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Concentration factor; Macronutrients; Micronutrients; Metals. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000300005 |
| |
|
|
| Olivares,Elizabeth. |
| Tithonia diversifolia, a ruderal weedy species utilized in agroforestry, is widely distributed in the tropics, often being found in wasteland, margins of polluted city rivers and roadsides. The objective of this study was to compare plants sampled at a light and heavy traffic roadside for metal concentration and foliar compounds which may be related to senescence and/or detoxification of metals. The field survey was followed by an experiment in pots of Pb-acetate-supplemented soil to verify if the same response is obtained under controlled conditions with regard to Pb. The concentration of Pb in leaves and roots of plants sampled at a heavy traffic roadside was higher than in samples from a light traffic site. The content of Cr, Al, Fe, Cu and Ni was also... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Asteraceae; Metals; Mexican sunflower; Phenols; Pollution; Weeds. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000300004 |
| |
|
|
| Jesus,Daniel da Silva de; Azevedo,Bianca Oliveira de; Pinelli,Milena Santos; Korn,Maria das Graças Andrade; Azevedo Neto,André Dias de; Lucchese,Angélica Maria; Oliveira,Lenaldo Muniz de. |
| ABSTRACT: Martianthus leucocephalus is found in the semi-arid Northeast of Brazil and has high pharmacological potential due to the production of volatile compounds. This study aimed to evaluate the Cd (15, 30, 45 and 60µmol L-1), Cu (30, 60, 90 and 120µmol L-1) and Zn (150, 300, 450 and 600µmol L-1) levels on the growth of this species and its volatile compounds production. Apical cuttings were placed in plastic trays containing 6.0L nutrient solution, and after rooting, they were submitted to Cd, Cu and Zn treatments for 15 days. All the metals evaluated reduced the succulence and growth of all parts of M. leucocephalus . This effect was accompanied by the increase of Cd, Cu and Zn concentrations in all plant tissues. Volatile compounds content produced... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lamiaceae; Metals; Relative growth. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016001202110 |
| |
|
|
| Vidal Fernández, Judith Estela. |
| Este trabajo evaluó la respuesta de la simbiosis tripartita Rhizobium-leguminosa-micorriza arbuscular en presencia de vanadio (V) y níquel (Ni). El trabajo se dividió en dos fases experimentales; la primera fase estudió el comportamiento de la simbiosis Rhizobium tropici-Phaseolus vulgaris ante concentraciones de V o Ni (0, 25, 50, 75, 100 y 120 mg L-1) y su efecto en el contenido elemental en nódulos, en un sistema de bolsa de crecimiento bajo condiciones controladas (25°C, 70% HR y 12h de fotoperiodo) durante 30 días. En las plantas con V, la nodulación inició al cuarto día después de la inoculación y tuvo un máximo de 40 nódulos por planta en el testigo y 6 nódulos en las concentraciones de 50 y 100 mg L-1. La mayor actividad nitrogenasa (AN) se... |
|
Palavras-chave: Nodulación; Metales; Fitorremediación; Simbiosis; Phaseolus; Rhizophagus; Nodulation; Metals; Phytorremediation; Symbiosis; Edafología; Maestría. |
| Ano: 2012 |
URL: http://hdl.handle.net/10521/753 |
| |
|
|
| Idardare, Zaina; Chiffoleau, Jean-francois; Moukrim, A; Alla, A; Auger, Dominique; Lefrere, L; Rozuel, Emmanuelle. |
| Metal concentrations were measured monthly during an annual cycle (December 2004 to January 2006) in the tissues of Nereis diversicolor ragworms and sediment from two Moroccan Atlantic coastal lagoons: Oualidia in the north, situated in a highly industrialised urban area and Khnifiss in the south, far from anthropogenic influences. Relatively high levels of Zn, Ag and Cd were found in the sediment of Oualidia lagoon, while Ni concentrations were shown to be high at Khnifiss. The significant metal levels at Oualidia are a result of industrial and urban discharges, coupled with discharges from adjacent phosphate ore processing plants. Trace metal concentrations in worms vary according to season; they are usually high in winter and spring, in relation to the... |
| Tipo: Text |
Palavras-chave: Morocco; Coastal lagoons; Sediments; Nereis diversicolor; Metals. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6127.pdf |
| |
|
|
| Gagneux Moreaux, Sindy; Cosson, Richard P.; Bustamante, Paco; Moreau, Christophe. |
| The Bay of Bourgneuf, France, is a main site of shellfish production. In the marshes along the bay, oyster intensive rearing and fattening need the mass production of microalgae. Salt groundwaters, available in this region, support a large part of this production for aquaculture. Studies carried out by local authorities have brought to the fore the accumulation of lead (Pb) in several samples of algal pastes derived from cultures using salt groundwater. The aim of this study was to compare growth, nutritional value and metal (Cd, Cu, Pb and Zn) uptake of four microalgae grown in two salt groundwaters or in enriched coastal seawater. Cultures of microalgae used in aquaculture (Haslea ostrearia, Phaeodactylum tricornutum, Skeletonema costatum and Tetraselmis... |
| Tipo: Text |
Palavras-chave: Marine microalgae cultivation; Aquaculture; Metals; Growth; Prasinophycea; Bacillariophycea; Diatom; Bioaccumulation; Trace elements; Saline groundwater. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2135.pdf |
| |
|
| |
|
|
| Cosson, R; Thiebaut, E; Company, R; Castrec Rouelle, M; Colaco, A; Martins, I; Sarradin, Pierre-marie; Bebianno, M. |
| The variability of the bioaccumulation of metals (Ag, Cd, Cu, Fe, Mn and Zn) was extensively studied in the mussel Bathymodiolus azoricus from five hydrothermal vent sites inside three main vent fields of increasing depth along the Mid-Atlantic Ridge: Menez Gwen, Lucky Strike and Rainbow. Metal bioaccumulation varied greatly between vent fields and even between sites inside a vent field with B. azoricus showing a great capacity to accumulate metals. The bioaccumulation of these metals also varied significantly among tissues. The main target was the gills where metals were mainly associated with soluble compounds whereas in the digestive gland they were mainly associated with insoluble compounds. Storage of metals under insoluble forms in B. azoricus seems... |
| Tipo: Text |
Palavras-chave: Bathymodiolus; Mytilids; Hydrothermal vents; Azores; Metals; Bioaccumulation. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3954.pdf |
| |
|
| |
| Registros recuperados: 48 | |
|
|
|
