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Registros recuperados: 55 | |
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Cruz,Lútecia Hiera da; Santana,Henrique de; Zaia,Cássia Thaïs Bussamra Vieira; Zaia,Dimas Augusto Morozin. |
This work showed that the adsorption of glyphosate (GPS) depends on surface area for clays and amount of clays and CEC for soils. Organic matter (OM) had a secondary role in the adsorption of GPS on soils. The adsorption of GPS on soils from Londrina and Floraí counties and clays (montmorillonite, kaolinite) decreased when pH increased, however, for bentonite clay and soil from Tibagi county was kept constant. For the soils, the competitive adsorption between GPS and phosphate showed that displace of GPS by phosphate was related to the amount of clays, CEC and pH. GPS was not easily displaced by phosphate on the clays. The FT-IR spectra of the soils and clays showed that soil from Londrina resembled kaolinite. Thus, this could explain the results of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glyphosate; Adsorption; Clays; Soils. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000300004 |
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Lopes,Toni Jefferson; Gonçalves,Odinei Hess; Barros,Ricardo Barbosa; Capelli,Francine Carla Rodrigues; Machado,Ricardo Antonio Francisco; Quadri,Mara Gabriela Novy; Quadri,Marintho Bastos. |
The main purpose of this work was to produce a pellet to minimize undesirable effects in fixed beds, such as colmatation, through clay fixation on the surface of polymeric particles. Preliminary experiments were carried out by heating the clay, namely Tonsil Terrana 580FF, in order to observe variations on its capacity to adsorb anthocyanins derived from red cabbage. Clays was fixed on five samples of high density polyethylene (HDPE) at 180°C -210°C for two hours. The morphological analyses of the resulting particles were accomplished through Scanning Electron Microscopy (SEM). The experiments demonstrated an increase on clay's adsorptive capacity of 15.65% at 120°C for 30 hours and 16.80% at 170°C for two hours. The SEM analysis showed that the clay... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adsorption; Clay; Polymer; Anthocyanin/red cabbage. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000400034 |
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Gonçalves Junior,Affonso C.; Meneghel,Ana P.; Rubio,Fernanda; Strey,Leonardo; Dragunski,Douglas C.; Coelho,Gustavo F.. |
This study evaluated the efficacy of moringa seeds (Moringa oleifera Lam.) as an adsorbent material for removing toxic heavy metals such as cadmium, lead, and chromium from contaminated solutions. The effect of the adsorbent mass was investigated at two pH conditions (5.0 and 7.0). The optimized conditions were 0.300 g of adsorbent at pH 5.0, used for the isotherms construction, and linearized according to Langmuir and Freundlich models. Results showed that cadmium adsorption was similar in both the models used. For lead, the Freundlich model had the best adjustment and chromium was better adjusted by the Langmuir model. It was concluded that the adsorbent was effective in the remediation of solutions containing cadmium, lead and chromium, thus, its use as... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adsorption; Isotherms; Remediation. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662013000100013 |
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Clemente,Edmar; Afonso,Marcos Rodrigues Amorim; Souza,Ana Paula; Correia,José Maria; Pires,Raquel Gomes; Maia,Geraldo Arraes. |
Solid mixtures for refreshment are already totally integrated to the Brazilian consumers' daily routine, because of their quick preparation method, yield and reasonable price - quite lower if compared to 'ready-to-drink' products or products for prompt consumption, what makes them economically more accessible to low-income populations. Within such a context, the aim of this work was to evaluate the physicochemical and mineral composition, as well as the hygroscopic behavior of four different brands of solid mixture for mango refreshment. The BET, GAB, Oswim and Henderson mathematical models were built through the adjustment of experimental data to the isotherms of adsorption. Results from the physiochemical evaluation showed that the solid mixtures for... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adsorption; Isotherms; Mathematical models; Nutritious powders; Refreshment; Mango. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612011000300010 |
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Souza,M.D. de; Basssoi,L.H.; Bacchi,O.O.S.; Reichardt,K.; Hermes,L.C.; Abakerli,R.B.; Pilotto,J.E.. |
Atrazine displacement was studied in a soil profile as a function of water movement and time after herbicide application, taking into account possible influence of preferential flow on leaching. The experiment consisted of two 7 x 7m plots of a dark red latosol (Kanduidalfic Eutrudox), located at Piracicaba, SP, Brazil (22º 43'S and 47º 25'W), 250km inside continent, at an altitude of 580m. One plot was previously treated with 1,000 kg/ha of lime, in order to increase base saturation to 88%, and 500kg/ha of gypsum. Each plot was instrumented with tensiometers, neutron probe access tubes and soil solution extractors, in order to monitor water and atrazine flows. Atrazine was applied at the high rate of 6 kg/ha of active principle. Results showed intensive... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Atrazine; Leaching; Preferential flow; Adsorption; Herbicide; Tropical soil. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161997000300013 |
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ROMBALDO,CARLA F.S.; LISBOA,ANTONIO C.L.; MENDEZ,MANOEL O.A.; COUTINHO,APARECIDO R.. |
Jute fiber is the second most common natural cellulose fiber worldwide, especially in recent years, due to its excellent physical, chemical and structural properties. The objective of this paper was to investigate: the thermal degradation of in natura jute fiber, and the production and characterization of the generated activated carbon. The production consisted of carbonization of the jute fiber and activation with steam. During the activation step the amorphous carbon produced in the initial carbonization step reacted with oxidizing gas, forming new pores and opening closed pores, which enhanced the adsorptive capacity of the activated carbon. N2 gas adsorption at 77K was used in order to evaluate the effect of the carbonization and activation steps. The... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Activation; Adsorption; Carbonization; Jute fiber; Thermogravimetry. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000402137 |
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de Bruijn,Johannes; Valdebenito,Ana; Loyola,Cristina; Serra,Ignacio; Salazar,Fernando; López,Francisco. |
Unstable proteins may react with polyphenols, forming haze and precipitation in white wines. Therefore, the adsorption of these wine proteins is an essential step in the production of white wines. The objective of this study was to determine the influence of adsorption of these proteins on the stability, and protein and phenolic composition of a Chardonnay wine. In this work, protein stabilization of Chardonnay wine was done by continuous adsorption using a packed bed with a SP-Trisacryl-M adsorbent (Sigma-Aldrich). A more pronounced breakthrough of proteins and turbidity causing compounds was found after treating 65 bed volumes of wine by the resin. An increased retention of the protein fraction of 20-50 kDa during the first 62 bed volumes of treated wine... |
Tipo: Journal article |
Palavras-chave: Adsorption; Trisacryl; Fining; Chile. |
Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392009000100007 |
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Silveira,Maria Lucia Azevedo; Alleoni,Luís Reynaldo Ferracciú. |
Cu adsorption, at concentrations between 0 to 800 mg L-1, was evaluated in surface and subsurface samples of three Brazilian soils: a heavy clayey-textured Rhodic Hapludalf (RH), a heavy clayey-textured Anionic ''Rhodic'' Acrudox (RA) and a medium-textured Anionic ''Xanthic'' Acrudox (XA). After adsorption, two consecutive extractions were performed to the samples which received 100 mg L-1 copper. Surface samples adsorbed higher amounts of Cu than the subsurface, and exhibited lower Cu removed after the extractions, reinforcing the influence of the organic matter in the reactions. Cu adsorption was significant in the subsurface horizons of the Oxisols, despite the positive balance of charge, demonstrating the existence of mechanisms for specific... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adsorption; Isotherms; Desorption; Tropical soil. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000400006 |
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Ridame, C; Moutin, T; Guieu, C. |
A Saharan soil, considered as a proxy for Saharan aerosols, was used to perform radio-labelled phosphate adsorption experiments using (33)PO(4)(3-): leached particles were exposed to poisoned western Mediterranean seawater for varying lengths of time. The measured adsorption capacity of Saharan dust for phosphate was 0.13 mumol g(-1). Considering this value and an annual Saharan dust deposition of 12.5 t km(-2) year(-1), we show that Saharan particles do not represent a significant sink for seawater phosphate in the western Mediterranean Sea. This result is in agreement with that determined from a similar approach conducted in the eastern basin. As a consequence, the unusual NIP ratio measured in the whole Mediterranean Sea (up to 29) cannot be explained... |
Tipo: Text |
Palavras-chave: Poussières sahariennes; Adsorption; Phosphate; Rapport N/P; Méditerranée; Saharan dust; Adsorption; Phosphate; N/P ratio; Mediterranean Sea. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00321/43254/42985.pdf |
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Suppadit,Tawadchai; Kitikoon,Viroj; Phubphol,Anucha; Neumnoi,Penthip. |
Biochar can improve soil structure and water retention, enhance nutrient availability and retention, ameliorate acidity, and reduce heavy metal toxicity to plant roots. In this study, a basin experiment was conducted to investigate the effects of quail litter biochar (QLB) on the availability of Cd to physic nut (Jatropha curcas L.) plants. QLB was applied to the soil in which four new physic nut varieties (Takfa, Doi Saket, Lao, and Rayong) in factorial combinations at four levels (0, 5, 10, and 15 g kg-1 soil) to soil that contained 60.8 mg Cd kg-1. After transplanting plant height and canopy radius were measured every 2-mo and the number of leaves and branches at 6-mo, while yield components and Cd residues were measured at 8-mo intervals. The... |
Tipo: Journal article |
Palavras-chave: Adsorption; Heavy metal; Phytoremediation; Plant production; Pyrolysis; Soil amendment. |
Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000100020 |
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Registros recuperados: 55 | |
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