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| Registros recuperados: 61 | |
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| Vranken, G.; Heip, C.H.R.. |
| Toxicity of copper, lead and mercury to the nematode <i>Diplolaimella</i> spec 1 is studied. Mortality responses obtained demonstrate high resistance to heavy metals. Population growth parameters as the intrinsic rate of natural increase and net-reproductivity are significantly depressed at copper-concentrations which cause no juvenile mortality. The lowest concentrations tested caused significant inhibition of development rate in both sexes. For this particular nematode species suppression of fecundity and developmental inhibition are more reliable criteria, determining non-exceedable limits with regard to environmental safety. Our tests show that nematode productivity may be significantly depressed at copper levels found in some areas of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Lead; Mercury; Toxicity; Nematoda [Nematodes]. |
| Ano: 1986 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3250 |
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| Arzul, Genevieve; Youenou, A.; Derrien, Annick; Gentien, Patrick; Crassous, M.p.; Lunven, M.. |
| The study of different chemical parameters characterizing the coastal sediment, showed a possible relation between, respectively, high levels in organic matter and total copper, and the "red tide" phenomenon. |
| Tipo: Text |
Palavras-chave: Sédiment côtier; Eaux colorées; Matière organique; Cuivre; Coastal sediment; Red time; Organic matter; Copper. |
| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00425/53708/54565.pdf |
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| Kondajii, N; Menon, N. |
| It is understood that the rate of bioaccumulation and subsequent depuration of heavy metals in marine animals is influenced by the chemical state, as well as the kinetics of transformation between different species of chemical salts dissolved in water. The Indian Brown mussel, Perna indica, was exposed to copper nitrate and chloride, individually, to analyse the rate of accumulation, depuration, oxygen uptake and filtration rates. When supplied in very low quantities, environmentally realistic concentrations, the rate of accumulation of copper nitrate and chlorides showed variations. When the animals were transferred to sea water, these two salts did not show any clear cut differences in the depuration rate. Irrespective of the previous accumulation... |
| Tipo: Text |
Palavras-chave: Perna indica; Bivalvia; Chlorides; Copper; Mussel culture; Heavy metals; Marine pollution; Accumulation; Self purification. |
| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/acte-1603.pdf |
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| Sokolowski, A; Wolowicz, M; Hummel, H; Bogaards, R. |
| Physiological and behavioral responses to Cu exposure were measured in the Baltic clam Macoma balthica from the Gulf of Gdansk, southern Baltic Sea. The burrowing activity, mortality rate, glycogen content, condition index and free amino acid (FAA) composition were analysed as indicators of stress in a series of field and laboratory studies. M. balthica exposed to Cu showed clear Cu-concentration related differences in burrowing activity and mortality rate, but no consistent differences in the condition index, glycogen content, and free amino acids. The clams from a less polluted area reacted more strongly and were more sensitive to additional stress as compared to organisms from a more polluted region. The effect of Cu on the ecophysiology of Baltic clams... |
| Tipo: Text |
Palavras-chave: Stress; Cuivre; Écophysiologie; Macoma balthica; Mer Baltique; Stress; Copper; Ecophysiology; Macoma balthica; Baltic Sea. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43606/43925.pdf |
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| Pratap, H.B.; Mamboya, F.A.; Mtolera, M.S.P.; Björk, M.. |
| The effect of copper (Cu) on the daily growth rate (DGR) and photosynthetic efficiency (PE) of the brown macroalga Padina boergesenii was studied under controlled laboratory conditions. The DGR was measured as an increase in fresh weight while the PE was measured as the ratio of variable to maximal chlorophyll fluorescence (Fv/Fm). Padina boegesenii were exposed to 25, 50, 100 and 500mg Cu/l for 21 days. The DGR and PE of P. boergesenii decreased significantly with an increase in copper concentration in the growth media. This study shows that copper is acutely toxic to P. boergesenii at concentrations higher than 500mg Cu/l. Low concentration of copper is toxic to P. boergesenii after a prolonged exposure of 21 days. Similarly, exposure time has a... |
| Tipo: Proceedings Paper |
Palavras-chave: Copper; Algae. |
| Ano: 1999 |
URL: http://hdl.handle.net/1834/787 |
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| MORAES, S. da S.. |
| Deficiências e desequilíbrios minerais em bovinos são descritas em quase todas as regiões do mundo. Os elementos minerais comumente deficientes para bovinos com dieta exclusiva de pasto são: P, Na, I, Cu, Co, e Se. Em algumas regiões sob condições especificas, Ca, Mg e Mn. Por outro lado, Fe e Mn estão, normalmente, em excesso nas regiões do Cerrado Central do Brasil e Pantanal. A ingestão de dietas deficientes ou desequilibradas de elementos minerais torna mais difícil a manutenção de concentrações ótimas nos tecidos . No inicio, causa lesões bioquímicas que induzem a trocas nas formas de funcionamento, concentração e atividade do elemento nos fluidos e tecidos do corpo. Essas alterações diferem conforme os elementos e suas funções, com o grau de duração... |
| Tipo: Documentos (INFOTECA-E) |
Palavras-chave: Bovino de corte; Brasil; Mineral deficiencies; Sulphur; Yodine.; Cálcio; Cloro; Cobre; Cobalto; Deficiência Mineral; Ferro; Enxofre; Fósforo; Manganês; Magnésio; Iodo; Potássio; Selênio; Sódio; Zinco.; Calcium; Cobalt; Copper; Brazil; Beef cattle; Chlorine; Iron; Magnesium; Manganese; Phosphorus; Potassium; Sodium; Selenium; Zinc.. |
| Ano: 2001 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/325198 |
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| Spitzner,Reinaldo. |
| The author presents an analytic process for copper quantitative determination in mineral and potable waters, based in the reaction of the cation copper with sodium diethyl-dithio carbamate. Due to the presence of certain elements common in water, such as iron, calcium, magnesium, etc., the main principles of the reactions behavior were studied. In the same manner the reaction sensibility was verified, as well as its precision, by the addition of known quantities of copper. About the end of the work presented, there are shown some copper determinations made through the mentioned process with mineral and potable waters of Paraná. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Photometry; Mineral waters. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000500004 |
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| Lofgren, Hans; Robinson, Sherman; Thurlow, James. |
| Zambia's strong dependence on copper exports has suppressed other tradables sectors, indicative of a Dutch disease phenomenon. The current copper crisis will have strong economic effects, possibly reversing such Dutch disease effects. We use a computable general equilibrium model built around a 1995 social accounting matrix to simulate the short- and long-run effects of two scenarios that reflect the current crisis, a 20 percent reduction in world copper prices and a complete collapse of copper mining. Compared to the short run, the long run is characterized by more flexibility in production technology and capital allocation. Both scenarios require a significant reduction in the "non-copper" trade deficit, absorption, and household consumption. The... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Zambia; Copper; Structural adjustment; Agriculture; General equilibrium; International Development; C68; O55; Q17; Q32. |
| Ano: 2003 |
URL: http://purl.umn.edu/25805 |
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| Brainer,Mônica Maria de Almeida; Menten,José Fernando Machado; Vale,Marcos Martinez do; Morais,Sônia Cristina Daroz de. |
| Feeding cupric citrate as alternative to cupric sulfate to broilers has been suggested in the literature. Day-old male broiler chicks (1,200) were used in an experiment to evaluate the efficacy of cupric citrate supplementation (75 mg Cu kg-1) during the 1-21, 22-42 or 1-42 d periods in comparison to an unsupplemented diet and a diet supplemented with cupric sulfate (200 mg Cu kg-1, 1-42 d). A randomized block design was used, with five treatments, six replicates and 40 birds per pen. The diets, based on corn and soybean meal, and water were offered ad libitum during the 42-day experimental period. Over the entire period, there was no effect of copper supplementation (P > 0.05) on bird live weight, weight gain, feed intake, feed conversion and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Broiler litter; Poultry; Copper; Performance. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000300004 |
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| Registros recuperados: 61 | |
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