Consulta: subjectFacets:"Adsorption"
Registros recuperados: 51
Data/hora: 14/06/2024 14:03:58

Parámetros de Transporte de Atrazina en un Andosol y un Vertisol de México
Provedor de dados: 32
Autores: Raymundo Raymundo, Elías.
Atrazina es el herbicida más utilizado en el mundo y el tercer herbicida más utilizado en México.  Atrazina tiene potencial cancerígeno en humanos. En varias partes del mundo esta sustancia se  ha detectado en aguas superficiales y subterráneas a niveles que rebasan las concentraciones  máximas permisibles para agua potable. Se ha realizado el presente estudio con la finalidad de  entender las particularidades de transporte de atrazina a través del perfil de un Andosol y un  Vertisol mexicanos y obtener los parámetros de transporte, los cuales permiten simular el  proceso de migración y mejorar las estrategias de aplicación para prevenir la contaminación  ambiental. Bajo condiciones de laboratorio, se condujeron columnas intactas y empacadas de  suelos...
Tipo: Tesis
Palavras-chave: Velocidad; Degradación; Adsorción; Columnas intactas y empacadas; Retardo; Doctorado; Hidrociencias; Velocity; Degradation; Adsorption; Intact and packed columns; Retardation.
Ano: 2008
URL: http://hdl.handle.net/10521/1308

Natural carriers in bioremediation: A review
Provedor de dados: 69
Autores: Dzionek,Anna; Wojcieszy&amp;#324;ska,Danuta; Guzik,Urszula.
Bioremediation of contaminated groundwater or soil is currently the cheapest and the least harmful method of removing xenobiotics from the environment. Immobilization of microorganisms capable of degrading specific contaminants significantly promotes bioremediation processes, reduces their costs, and also allows for the multiple use of biocatalysts. Among the developed methods of immobilization, adsorption on the surface is the most common method in bioremediation, due to the simplicity of the procedure and its non-toxicity. The choice of carrier is an essential element for successful bioremediation. It is also important to consider the type of process ( n s tu or ex s tu), type of pollution, and properties of immobilized microorganisms. For these reasons,...
Tipo: Journal article
Palavras-chave: Adsorption; Bioethanol production; Contamination; Heavy metals; Immobilization; Immobilized microorganisms; Natural carriers; Wine alterations; Wood barrels; Xenobiotics.
Ano: 2016
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500008

Removal of malachite green from water by Firmiana simplex wood fiber
Provedor de dados: 69
Autores: Pan,Xiangliang; Zhang,Daoyong.
This study shows that wood fiber of Phoenix tree (Firmiana simplex) is an effective adsorbent for malachite green (MG). MG sorption behavior onto the wood adsorbent was investigated in this study. Basic condition was favorable for MG adsorption to the adsorbent. The pseudo second order equation well described MG adsorption onto the wood adsorbent. The Freundlich Isotherm could describe the sorption data. The positive value of &amp;#916;H0 showed that adsorption of malachite green onto the wood adsorbent was endothermic. The negative values of &amp;#916;G at various temperatures indicate the spontaneous nature of the adsorption process.
Tipo: Journal article
Palavras-chave: Adsorption; Kinetics; Malachite green; Thermodynamics; Wood fiber.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582009000400009

Comment on &amp;#8220;Equilibrium sorption isotherm studies of Cd(II), Pb(II) and Zn (II) ions detoxification from waste water using unmodified and EDTA-modified maize husk&amp;#8221;
Provedor de dados: 69
Autores: Cavas,Levent.
The citing and using of correct version of mathematical equations are of great importance in the writing of a scientific paper. This paper presents the possible errors related to Dubinin-Radushkevich Equation in an article by Igwe and Abia (2007) which was published in Electronic Journal of Biotechnology, 10(4); 536-548.
Tipo: Journal article
Palavras-chave: Adsorption; Calculation errors; DR equation.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200001

Overproduction of clavulanic acid by extractive fermentation
Provedor de dados: 69
Autores: Lopes Costa,Cecília Ladeira; Colli Badino,Alberto.
Background Clavulanic acid is an important beta-lactamase inhibitor produced as a secondary metabolite by the actinomycete Streptomyces clavuligerus. Clavulanic acid is chemically unstable; therefore, it is degraded during bacterial cultivation. In this work, the adsorbents clinoptilolite, activated carbon, calcined hydrotalcite, and Amberlite IRA 400 anionic exchange resin were studied in terms of their ability to adsorb clavulanic acid during extractive fermentation, in order to prevent product degradation and avoid product concentrations reaching inhibitory levels. Adsorption assays were used to investigate the effect of pH, and the decrease in the clavulanic acid concentration in the culture broth was measured for each adsorbent. Results IRA 400 was...
Tipo: Journal article
Palavras-chave: Adsorption; Clavulanic acid; Extractive fermentation; Integrated processing; Product inhibition.
Ano: 2015
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582015000300003

Evaluation of two bioadsorbents for removing paracetamol from aqueous media
Provedor de dados: 69
Autores: Flores Nardy Ribeiro,Araceli Verónica; Belisário,Marciela; Moretto Galazzi,Rodrigo; Cazoni Balthazar,Daniele; Godoi Pereira,Madson de; Nardy Ribeiro,Joselito.
The frequent contamination of water resources with drugs comprises one the most important environmental problems. In order to avoid serious disturbances for aquatic life, efficient and economically viable procedures should be developed for removing common pollutants, as paracetamol. From these considerations, the present work evaluated the efficiency of sugar cane bagasse (SCB) and vegetable sponge (VS), two natural adsorbents commonly found in Brazil, for retaining paracetamol molecules dispersed in aqueous solutions. Thus, systems composed of glass columns and peristaltic pumps were optimized and, for pH, the best value was 7.0. After optimisation, adsorption isotherms were built and it was possible to calculate the MAC F values for SCB (120.5 µg/g) and...
Tipo: Journal article
Palavras-chave: Adsorption; Bioadsorbent; Paracetamol; Water.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000600007

Sorption kinetics of Pb2+ and Cu2+ ions from aqueous solution by Nipah palm (Nypa fruticans Wurmb) shoot biomass
Provedor de dados: 69
Autores: Wankasi,Donbebe; Horsfall Jnr,Michael; Ibuteme Spiff,Ayabaemi.
The sorption kinetics of Pb2+ and Cu2+ ions in aqueous solution by unmodified and mercaptoacetic acid modified biomass of Nypa fruticans shoot has been investigated. The equilibrium sorption capacity of Pb2+ and Cu2+ was determined from the Langmuir equation and found to be 15.59 mg/g and 21.85 mg/g for unmodified biomass and 52.86 mg/g and 66.71 mg/g for modified biomass at 30&amp;ordm;C. The time dependent studies showed relatively rapid sorption of 5 - 10 min to reach equilibrium for both metal ions. A batch sorption model, based on the assumption of the pseudo-second-order mechanism, was applied to predict the rate constants (g mg-1 min-1), which were found to be 3.59 x 10-4 (Pb2+) and 1.85 x 10-4 (Cu2+) and 2.82 x 10-2 (Pb2+) and 3.67 x 10-2 (Cu2+) on...
Tipo: Journal article
Palavras-chave: Adsorption; Heavy metal binding; Nipah palm.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000500015

SORPTION ISOTHERMS AND ISOSTERIC HEAT OF PERICARP AND ENDOSPERM TISSUES OF ARABICA COFFEE FRUIT
Provedor de dados: 70
Autores: Dias,Camila de A.; Andrade,Ednilton T. de; Lemos,Isabella A.; Borém,Flávio M.; Barros,Ezequiel A.
ABSTRACT The aim of this study was to evaluate and model the hygroscopic equilibrium and isosteric heat curves of pericarp and endosperm tissues of arabica (Coffea arabica) coffee fruit, in different temperature and relative humidity conditions. Sorption isotherms were drawn under temperatures from 20°C to 70°C and relative humidity ranging between 10% and 90% until the product reached the equilibrium water content with the environment. The experiment was set up in a 4 × 4 factorial scheme (four relative humidity of the drying air and three tissues of the coffee cherry pericarp + endosperm [1: exocarp + part of the mesocarp, 2: mesocarp, 3: endocarp, 4: endosperm]), in a completely randomized design, with three repetitions. The results were examined by...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Coffea arabica; Desorption; Hygroscopic equilibrium; Mathematical modeling.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000100078

MATHEMATICAL MODELING AND HYSTERESIS OF SORPTION ISOTHERMS FOR PADDY RICE GRAINS
Provedor de dados: 70
Autores: Zeymer,Juliana S.; Corrêa,Paulo C.; Oliveira,Gabriel H. H.; Baptestini,Fernanda M.; Campos,Renata C.
ABSTRACT Knowledge on sorption isotherms is important for predicting drying and storage processes of a product. A sorption isotherm can be generated from two processes: desorption and adsorption. The lag between these two curves is called hysteresis. Static method was used to obtain the equilibrium moisture content of paddy rice grains, in different temperature (10, 20, 30, 40 and 50 ± 1°C) and relative humidity (between 11 and 76% ± 2%) conditions. Equilibrium moisture content data were correlated with eight mathematical models and. The Chung Pfost model had the best fit to the experimental data. Desorption and adsorption isotherms, represented by the Chung Pfost model, showed a sigmoidal shape, characteristic of type II curve. Equilibrium moisture...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Desorption; Hygroscopic equilibrium; Relative humidity; Temperature.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000400524

Фосфорный обмен природной взвеси в эстуариях рек Дунай и Чорох
Provedor de dados: 13
Autores: Поповичев, В. Н.; Егоров, В. Н.
Представлены данные экспериментальных исследований закономерностей фосфорного обмена различными фракциями природной взвеси из поверхностного слоя зон смешения речных вод Дуная и Чороха с черноморскими водами, соответственно для весеннего и осеннего сезонов. Получено, что интенсивность фосфорного обмена взвеси из эстуарной зоны Чороха более чем на порядок выше по сравнению с дунайской. Период круговорота минерального фосфора составляет диапазон значений от 2.9 до 14.3 часов для эстуария Чороха и от 2.9 до 8.8 суток  –  для эстуария Дуная. Фосфорный обмен биотической компоненты взвеси из эстуарной зоны Дуная имеет первый порядок метаболических реакций и нулевой – для зоны Чороха. Для эстуария Чороха в диапазоне солёности от 9.3 до 17.9 ‰ основной вклад...
Tipo: Journal Contribution
Palavras-chave: Природная взвесь; Фосфорный обмен; Поглощение; Адсорбция; Зоны смешения; Черное море; Natural suspended matter; Phosphorus exchange; Absorption (uptake); Adsorption; Mixing zones; The Black Sea Adsorption Adsorption http://aims.fao.org/aos/agrovoc/c_137.
Ano: 2003
URL: http://repository.ibss.org.ua/dspace/handle/99011/165

Adsorcao de defensivos agricolas em solos dos cerrados: caso do aldicarb.
Provedor de dados: 14
Autores: CARDOSO, A. N.; FERREIRA, G.; SOUSA, D. M. G. de; REIN, T. A.; OLIVEIRA, S. A. de; COTTA, T. A.
bitstream/item/107116/1/pesq-70.pdf
Tipo: Outras publicações técnicas (INFOTECA-E)
Palavras-chave: Defensivo agricola.; Adsorção; Agricultura; Cerrado; Solo.; Adsorption; Agriculture; Aldicarb; Soil.
Ano: 1994
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/549409

Compréhension des mécanismes d'adhésion des biofilms en milieu marin en vue de la conception de nouveaux moyens de prévention
Provedor de dados: 5
Autores: Rubio, Celine.
Biofilm formation on surfaces immersed in sea water induces equipment damages. Recently, studies focused on the environmental impact of antifouling paints have shown that some active chemical compounds are harmful to the aquatic environment. Hence, it appears fundamental to study physico-chemical interactions existing between marine bacteria and various substrata to conceive new ecological products or antifouling processes.  First, we model an artificial primary organic film, formed by the adsorption of BSA and polysaccharide, as close as the one formed in natural seawater. This organic film is heterogeneous (only 42% of the surface is covered) and organic adsorption occurs in a multi-layer scheme, molecules bounded each others by calcium and magnesium...
Tipo: Text
Palavras-chave: Sea water; Marine bacteria; Physico chemical characterisation; MATS; XPS; IRAS; Adsorption; Bacterial adhesion; Biofim; Eau de mer; Bactéries marines; Caractérisation physicochimique; MATS; XPS; IRRAS; Adsorption; Adhésion bactérienne; Biofilm.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/these-222.pdf

Eléments azotés de la colonne d'eau et de l'interface eau-sédiment du bassin de Marennes-Oléron : influence des cultures d'huîtres
Provedor de dados: 5
Autores: Feuillet-girard, Michelle; Heral, Maurice; Sornin, Jean-marc; Deslous-paoli, Jean-marc; Robert, Jean-michel; Mornet, Francoise; Razet, Daniel.
The respective influences of the sediment and of oyster (Crassostrea gigas) farming on the accumulation and the recycling of different forms of organic and inorganic nitrogen are described. Fluxes of dissolved inorganic and organic forms of nitrogen were studied between the water column, the water overlying the sediment and the pore waters, while for particulate forms the fluxes were studied between suspended material, the "biodeposits" (faeces and pseudofaeces of Crassostrea) and the sediment. The flux of inorganic nitrogen amounts to 10.5 106 g.m(-2). Yr(-1), while that of organic nitrogen is half this figure. The particulate flux is 15.106 g.m(-2).yr(-1). On the other hand, the phytoplanktonic nitrogen accounts for only 6% of the total particulate...
Tipo: Text
Palavras-chave: Marenne Oleron; Sediment; Pore water; Interface; Crassostrea gigas; Nitrogen; Marennes Oléron; Sédiment; Eau interstitielle; Adsorption; Interface; Crassostrea gigas; Azote.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/1988/publication-2878.pdf

Virus Type-Specific Removal in a Full-Scale Membrane Bioreactor Treatment Process
Provedor de dados: 5
Autores: Miura, Takayuki; Schaeffer, Julien; Le Saux, Jean-claude; Le Mehaute, Philippe; Le Guyader, Soizick.
We investigated removal of noroviruses, sapoviruses, and rotaviruses in a full-scale membrane bioreactor (MBR) plant by monitoring virus concentrations in wastewater samples during two gastroenteritis seasons and evaluating the adsorption of viruses to mixed liquor suspended solids (MLSS). Sapoviruses and rotaviruses were detected in 25% of MBR effluent samples with log reduction values of 3- and 2-logs in geometric mean concentrations, respectively, while noroviruses were detected in only 6% of the samples. We found that norovirus and sapovirus concentrations in the solid phase of mixed liquor samples were significantly higher than in the liquid phase (P &lt; 0.01, t test), while the concentration of rotaviruses was similar in both phases. The efficiency...
Tipo: Text
Palavras-chave: Norovirus; Sapovirus; Rotavirus; MBR; Mixed liquor suspended solids; Adsorption.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00414/52548/53441.pdf

Does phosphate adsorption onto Saharan dust explain the unusual N/P ratio in the Mediterranean Sea?
Provedor de dados: 5
Autores: 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

MOBILITY AND BIOAVAILABILITY OF HEAVY METALS AND METALLOIDS IN SOIL ENVIRONMENTS
Provedor de dados: 126
Autores: Violante,A; Cozzolino,V; Perelomov,L; Caporale,A.G; Pigna,M.
In soil environments, sorption/desorption reactions as well as chemical complexation with inorganic and organic ligands and redox reactions, both biotic and abiotic, are of great importance in controlling their bioavailability, leaching and toxicity. These reactions are affected by many factors such as pH, nature of the sorbents, presence and concentration of organic and inorganic ligands, including humic and fulvic acid, root exudates, microbial metabolites and nutrients. In this review, we highlight the impact of physical, chemical, and biological interfacial interactions on bioavailability and mobility of metals and metalloids in soil. Special attention is devoted to: i) the sorption/desorption processes of metals and metalloids on/from soil components...
Tipo: Journal article
Palavras-chave: Bioavailability; Heavy metals; Metalloid; Adsorption; Desorption; Chemical speciation.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-95162010000100005

Kinetic and isotherm studies of copper (II) removal from wastewater using various adsorbents
Provedor de dados: 20
Autores: Abdel Wahab, O.
The present investigation deals with the utilization of marine green algae (GA), Ulva lactuca, and an activated carbon prepared from green algae (CGA) as adsorbents for the removal of copper from wastewater. A series of experiments were conducted in a batch system to evaluate the effect of system variables. The effect of pH, initial copper concentration, dose of adsorbents were considered. The optimal pH value of copper (II) adsorption onto GA and CGA was found to be pH 5.0. The maximum uptake capacities were 24.5 and 32.3 mg copper (II) per gram of GA and CGA, respectively. The efficiency of removal was slightly changed by replacing an aqueous solution by saline water or wastewater containing the same copper concentration. Adsorption kinetic data were...
Tipo: Journal Contribution
Palavras-chave: Laboratory Study; Adsorption; Kinetics; Isotherms; Waste water; Adsorption; Http://aims.fao.org/aos/agrovoc/c_137.
Ano: 2007
URL: http://hdl.handle.net/1834/1910

Etude comparative de l’absorption de l’azote par deux espèces d’algues rouges : &lt;Gracilaria verrucosa&gt; (Hudson) papenfuss, 1950 et Gracilaria &lt;Bursa-pastoris&gt; (gmelin) silva, 1952.
Provedor de dados: 20
Autores: Romdhane, M.S.; Chebil-Ajjabi, L.; El Abed, A.
Afin de mettre en évidence l’aptitude de deux espèces d’algues rouges Gracilaria verrucosa et Gracilaria bursa-pastoris pour le traitement des effluents et leur utilisation potentielle, une série d’expériences a été réalisée ayant pour but d’expliquer le comportement de ces deux espèces d’algues vis à vis de la source d’azote.  Dans une première expérience, on a pu déterminer la forme d’azote (N-NH4 , N-NO3) preférentielle pour chacune des deux espèces d’algues cultivées séparément. Elles ont une nette préférence pour N-NH4 et cela pour une même concentration initiale. Cependant, G. verrucosa  est  un candidat plus performant que G. bursa-pastoris pour l’assimilation des deux formes d’azote. Etant identifié comme source préférentielle, N-NH4 a été utilisé...
Tipo: Journal Contribution
Palavras-chave: Adsorption; Algal culture; Nitrogen; Nutrients (mineral); Wastewater treatment; Adsorption; Nitrogen; Algal culture; Wastewater treatment; Http://aims.fao.org/aos/agrovoc/c_137; Http://aims.fao.org/aos/agrovoc/c_5192; Http://aims.fao.org/aos/agrovoc/c_31892; Http://aims.fao.org/aos/agrovoc/c_25312.
Ano: 2005
URL: http://hdl.handle.net/1834/3776

An automated method for the assessment of mercury adsorption rates on particulate suspended matter
Provedor de dados: 27
Autores: Baeyens, W.F.J.; Decadt, G.; Dehairs, F.A.; Goeyens, L.
A continuous filtration system connected to a mercury auto-analyzer has been constructed for obtaining mercury adsorption rates on particulate suspended matter. The capabilities of this device have been demonstrated by carrying out a series of experiments under controlled physicochemical parameter conditions on samples of the Scheldt estuary. Duplicate measurements showed coefficients of variation ranging from 1 to 6 %. Depending on the physico-chemical conditions, the initial adsorption rate per unit of dissolved mercury concentration varied between 1.2 and 8.1 x 10&lt;sup&gt;-2&lt;/sup&gt; mn&lt;sup&gt;-1&lt;/sup&gt;.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Mercury; Methodology; Particulates; Suspended matter.
Ano: 1982
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3413

Humic Substances and their Relation to Pesticide Sorption in Eight Volcanic Soils
Provedor de dados: 87
Autores: ALISTER,C.; ARAYA,M.; CORDOVA,A.; SAAVEDRA,J.; KOGAN,M.
ABSTRACT: Pesticide soil sorption is a primary factor that influences the fate of pesticides in the environment, affecting regulation of microbiological and chemical degradation, volatilization and leaching. The main goal of this research was to study the effect of the organic phase of volcanic soils on sorption of agricultural pesticides. Sorption and desorption of eight agricultural pesticides were studied on eight volcanic soils that varied in the fulvic and humic constituents of their organic matter. For all pesticides, sorption was well described by a Freundlich isotherm where 1/nads values indicated that the sorption mechanism could be mainly explained by physical reactions in all soils. Kf values for carbaryl and flumioxazin were the highest with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Desorption; Isotherms; Freundlich.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582020000100221

Functionalized Charcoal as a Buffering Matrix of Copper and Zinc Availability
Provedor de dados: 90
Autores: Guimarães,Gelton Geraldo Fernandes; Giroto,Amanda Soares; Teixeira,Breno Cardoso; Vergütz,Leonardus; Cantarutti,Reinaldo Bertola.
ABSTRACT: High copper (Cu) and zinc (Zn) contents in soil can cause phytotoxicity to plants and contaminate surface and groundwater, with negative effects on agriculture and the environment. Functionalized charcoal (OCh) has high cation exchange capacity (CEC) and the ability to adsorb Cu and Zn and control their availability in the soil and water. An adsorption study at two pH levels was carried out to evaluate increasing Cu and Zn sorption capacity provided by the functionalization process of a charcoal. In addition, a kinetics study of competitive and non-competitive adsorption-desorption of Cu and Zn in OCh was also evaluated. The results showed that functionalized charcoal (Ch) increased CEC 8.7 times due to an increase in carboxyl and phenolic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Desorption; Metals; Remediation; Biochar.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100530

Kinetics of phosphorus sorption in soils in the state of Paraíba¹
Provedor de dados: 90
Autores: Santos,Hemmannuella Costa; Oliveira,Fábio Henrique Tavares de; Salcedo,Ignácio Hernan; Souza,Adailson Pereira de; Mota Silva,Valério Damásio da.
The soil P sorption capacity has been studied for many years, but little attention has been paid to the rate of this process, which is relevant in the planning of phosphate fertilization. The purpose of this experiment was to assess kinetics of P sorption in 12 representative soil profiles of the State of Paraíba (Brazil), select the best data fitting among four equations and relate these coefficients to the soil properties. Samples of 12 soils with wide diversity of physical, chemical and mineralogical properties were agitated in a horizontal shaker, with 10 mmo L-1 CaCl2 solution containing 6 and 60 mg L-1 P, for periods of 5, 15, 30, 45, 60, 90, 120, 420, 720, 1,020, and 1,440 min. After each shaking period, the P concentration in the equilibrium...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Kinetic equations; Phosphate; Tropical soils; Semi-arid soils.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000400024

Sulfamethoxazole sorption in eutrophic Regolithic Neosol
Provedor de dados: 91
Autores: Barros,Márcia A. M. F. de; Antonino,Antônio C. D.; Schuler,Alexandre R. P.; Lima,José R. de S.; Gondim,Manuella V. S.; Lima,Valmir F. de.
ABSTRACT This study aimed to evaluate sulfamethoxazole sorption kinetics and isotherms using batch method. The experiment was carried out in typic eutrophic Regolithic Neosol (0-20 and 20-60 cm layers) located in the private reserve of the Riacho do Papagaio farm, in São João, PE, Brazil. The tests were carried out under laboratory conditions at 24 ºC and sulfamethoxazole concentration was determined by high-performance liquid chromatography. The sorption experiment through the batch method used sulfamethoxazole solutions with concentrations of 10-3, 5.10-4, 10-4, 5.10-5, 10-5 and 5.10-6 mol L-1 to obtain the analytical curve. For this soil, sulfamethoxazole sorption kinetics was best described by a second-order model and the sorption isotherms were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Soil contamination; Interaction; Adsorption.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000700506

Applicability of Moringa oleifera Lam. pie as an adsorbent for removal of heavy metals from waters
Provedor de dados: 91
Autores: 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

Water sorption kinetics of damaged beans: GAB model
Provedor de dados: 91
Autores: Baptestini,Fernanda M.; Corrêa,Paulo C.; Vanegas,Jaime D. B.; Leite,Rafael; Botelho,Fernando M.; Campos,Renata C.
ABSTRACT The objective of this study was to model the water sorption kinetics of damaged beans. Grains with initial moisture content of 53.85%, dry basis (d.b.), were used. One portion of the grains was used to obtain desorption isotherms, while the other was subjected to drying until the moisture content of 5.26% (d.b.), so that it was subjected to the adsorption. For the induction of damage, a Stein Breakage Tester was used. To obtain the equilibrium moisture content, grains were placed in a climatic chamber at 20, 30, 40 and 50 ± 1 °C combined with relative humidity of 30, 40, 50, 70 and 90 ± 3%. The GAB model fitted well to the equilibrium moisture experimental data of damaged grains and control. With increasing temperature, the monolayer moisture...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hysteresis; Adsorption; Desorption; Phaseolus vulgaris L.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000800550

Effect Of pH, Phosphate and/or Malate on Sulfate Sorption on Andisols
Provedor de dados: 127
Autores: Pigna,Massimo; Jara,Alejandra A; Mora,María de la Luz; Violante,Antonio.
The sulfate sorption was studied on Andisols with variable mineralogical composition and low organic matter content in presence and absence of phosphate or malate ligands at different pH. Crystalline clay mineralogy was similar for all the studied samples, except for the 2C horizon of the pedon 2, which did not show crystalline minerals. The soil samples showed content of allophane ranging from 16% to 42%. The sulfate adsorption decreased when descending the first 3 horizons (A1, 2A2 and 3Bw1) of the pedon 1. This behavior was attributed to the decreasing organic carbon content. At different pH sulfate sorption was drastically decreased by increasing the pH from 4.0 to 7.0, precisely by 80% for sample 5 to 100% for sample 1. Experiments on the competitive...
Tipo: Journal article
Palavras-chave: Sulfate; Adsorption; Andisol; Mineralogical composition; Phosphate; Malate.
Ano: 2007
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912007000100005

MAGELLAN PEAT (Sphagnum magallanicum) AS NATURAL ADSORBENT OF RECALCITRAN SYNTHETIC DYES
Provedor de dados: 127
Autores: Sepulveda-Cuevas,Luisa A; Contreras-Villacura,Elsa G; Palma-Toloza,Carolyn L.
Colour abatement is a complex problem because the synthetic origin of the dyes used in the industry. The purpose of this study is to evaluate the feasibility of using Magellan peat (Sphagnum magallanicum) as an adsorbent of textile dyes, determining the physical-chemical characteristics of the peat by measuring the adsorptive capacity of the dyes as well as exploring the degrading potential of the native microorganisms they contain. The results obtained indicate that the peat has a specific surface area (BET) and a volume of 144.3 m² g-1 and 60% of meso- and macropores, respectively. The basicity of the peat surface is superior to acidity and the pH in which the neutrality is reached is about 3.1. Equilibrium concentrations for the basic, acid and reactive...
Tipo: Journal article
Palavras-chave: Adsorption; Dyes; Textile effluents.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912008000200005

Biosolids and heavy metals in soils
Provedor de dados: 63
Autores: Silveira,Maria Lucia Azevedo; Alleoni,Luís Reynaldo Ferracciú; Guilherme,Luiz Roberto Guimarães.
The application of sewage sludge or biosolids on soils has been widespread in agricultural areas. However, depending on their characteristics, they may cause increase in heavy metal concentration of treated soils. In general, domestic biosolids have lower heavy metal contents than industrial ones. Origin and treatment method of biosolids may markedly influence their characteristics. The legislation that controls the levels of heavy metal contents in biosolids and the maximum concentrations in soils is still controversial. In the long-term, heavy metal behavior after the and of biosolid application is still unknown. In soils, heavy metals may be adsorbed via specific or non-specific adsorption reactions. Iron oxides and organic matter are the most important...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sewage sludge; Adsorption; Speciation; PH; Organic matter.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000400029

Soil attributes and efficiency of sulfentrazone on control of purple nutsedge (Cyperus rotundus L.)
Provedor de dados: 63
Autores: Alves,Pedro Luís da Costa Aguiar; Marques Júnior,José; Ferraudo,Antonio Sergio.
In the soil, herbicides are submitted to absorption, leaching and degradation by physical, chemical and biological processes or absorbed by plants. All these processes are dependent on soil class and weather conditions and affect the product efficiency on weed control. The objective of this work was to investigate the influence of soil attributes on sulfentrazone efficiency for controlling purple nutsedge (Cyperus rotundus L. ). Soil samples from LVAd (Typic Haplustox), LVd, LVdf and LVef (Typic Haplustox and Typic Eutrustox), NVe (Rhodic Kandiustalf), and LVd (Typic Haplustox) were collected under two crop conditions aiming to have different clay, Fe oxides, and organic matter contents. The soil samples were submitted to granulometric, chemical and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Herbicide; Adsorption; Fe oxide; Classes of soils.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000300014

Atrazine movement in a dark red latosol of the tropics
Provedor de dados: 63
Autores: 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

Electrochemical attributes and availability of nutrients, toxic elements, and heavy metals in tropical soils
Provedor de dados: 63
Autores: Fontes,Mauricio Paulo Ferreira; Alleoni,Luís Reynaldo Ferracciú.
Electrochemical properties of soils are very important for the understanding of the physico-chemical phenomena which affect soil fertility and the availability of nutrients for plants. This review highlights the electrochemical properties of tropical soils, the behavior and the availability of nutrients, toxic elements and heavy metals in the soil, especially for soils with predominant variable charge minerals. Availability of the elements is related to ionic exchange, solution speciation, and electrostatic and specific adsorptive soil properties. Empirical and surface complexation models are briefly described, and some results of their application in tropical soils are presented. A better understanding of the role of the double diffuse layer of charges...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Electric charge; Adsorption; Model; Ionic exchange; Speciation.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000600014

Sorption and desorption of indaziflam degradates in several agricultural soils
Provedor de dados: 63
Autores: Alonso,Diego Gonçalves; Oliveira Jr,Rubem Silvério de; Koskinen,William Charles; Hall,Kathleen; Constantin,Jamil; Mislankar,Suresh.
ABSTRACT Processes regulating pesticide fate in the environment are influenced by the physicochemical properties of pesticides and soils. Sorption and desorption are important processes as they regulate the movement of pesticides in soil. Although sorption-desorption is widely studied for herbicides, studies involving their metabolites in soil are scarce. Sorption and desorption of indaziflam metabolites (indaziflam-triazinediamine (FDAT), indaziflam-triazine-indanone (ITI) and indaziflam-carboxilic acid (ICA)) were investigated in six Brazilian (BRA) soils and three United States (USA) soils with different physicochemical properties. The Freundlich equation described sorption of the metabolites for all soils (R2 &gt; 0.98; 1/n ~ 1). Sorption order (Kf)...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Hysteresis; Metabolites; Soil properties.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000200169

Moisture sorption isotherms of Mesquite seed (Prosopis africana)
Provedor de dados: 111
Autores: Ade, Ayokanmi Remi; Ajav, E A; Raji, Abdulganiy O; Adetayo, Seun Ayodele; Arowora, Kayode Adebisi.
Moisture profoundly influences product attributes such as quality and safety. The knowledge of moisture sorption isotherm is essential to determine products stability, and needed for design of storage, packaging and drying systems for extension of shelf lives. This study is to develop sorption isotherms of Prosopis africana.The moisture sorption isotherms of the seed were determined at temperatures of 20ºC, 25ºC and 30ºC, over a relative humidity range of 11%-100% using the static gravimetric technique. A linear regression programme was used to fit five isotherm models; GAB, Oswin, Halsey, Henderson, and Chung Pfost to the experimental data and compared using the root mean standard error, regression coefficient, standard error of estimate, and randomness...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Agrricultural Engineering Prospis africana; Equilibrium moisture content; Water activity; Adsorption; And desorption.
Ano: 2016
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3727

Development of moisture isotherms for Momordica charantia and Carica papaya
Provedor de dados: 111
Autores: Rupasinghe, chintha Priyangani; Jayasinghe, Udara; Sugathapala, Thusitha.
Safe moisture of a product is important in drying of agricultural products to prevent it from deterioration. The equilibrium moisture content (EMC) is an important parameter in modeling and simulation of drying process. The objectives of the research are development of an EMC curve for Agricultural Products; bitter gourd (Momordica charantia) and papaya (Carica papaya) and to test the suitability of mathematical models of modified Henderson’s equations. The study is performed on the basis of adsorption of moisture content, at three temperatures (30, 40 &amp; 50°C) and four relative humidity (Rh) (10, 30, 50 and 80%). Salt solutions with concentrations were used to maintain Rh. The statistical analysis was done to find the best model and the significant...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Post harvest technology Equilibrium moisture content; Adsorption; Isotherms; Mathematical model.
Ano: 2019
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5114

Sawdust Derivative for Environmental Application: Chemistry, Functionalization and Removal of textile dye from aqueous solution
Provedor de dados: 42
Autores: PINTO,THAIS F.; BEZERRA,CÍCERO W.B.; SILVA,DOMINGOS S.A.; SILVA FILHO,EDSON C. DA; VIEIRA,ADRIANA P.; AIROLDI,CLAUDIO; MELO,JÚLIO C.P. DE; SILVA,HILDO A.S.; SANTANA,SIRLANE A.A.
ABSTRACT The adsorption of Violet Remazol 5R (VR 5) on wood sawdust modified with succinic anhydride (SSA) as a function of contact time, pH, and initial dye concentrations was investigated using a batch technique under ambient conditions. The SSA obtained was confirmed by IR spectroscopy, thermogravimetry and 13C NMR, and degrees of substitution (DS) were calculated. A study on the effect of the pH on the adsorption of VR 5 showed that the optimum pH was 2.0. The interactions were assayed with respect to the pseudo-first-order and pseudo-second-order kinetic models, and were found to follow closely the pseudo-second-order. The isotherm was adjusted to the Langmuir, the Freundlich and the Temkin sorption models. SSA is a promising material for the removal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Wood sawdust; Adsorption; Textile dye; Succinic anhydride.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000401212

Brazilian natural fiber (jute) as raw material for activated carbon production
Provedor de dados: 42
Autores: 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

Adsorption of SOX and NOX in activated viscose fibers
Provedor de dados: 42
Autores: Plens,Ana Carolina O.; Monaro,Daniel L.G.; Coutinho,Aparecido R.
SOx and NOx are emissions resulting from combustion processes and are the main agents that contribute to the formation of acid rain, which causes harm to humans and the environment. Several techniques for removing these pollutants are applied in i.e. oil refineries, thermoelectric that use petroleum oils and vehicular pollution. Among these, highlight the adsorption of contaminants by the usage of activated carbon fibers and activated carbon, which are characterized by high surface area and uniform distribution of pores, providing appropriate conditions for application in processes of removing environmental contaminants. In the present work, activated viscose fibers (AVF) were prepared and applied in adsorption experiments of NO and SO2. The materials...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Activated carbon; Activated fibers; Adsorption; NOx; SOx.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000201149

Inclusion of Yucca schidigera and zeolite in dog feed: influence on mineral excretion
Provedor de dados: 45
Autores: Santos,J.P.F.; Saad,F.M.O.B.; Maia,G.V.C.; Pires,C.P.; Reis,J.S.; Roque,N.C.; Aquino,A.A.; Brunetto,M.A.
This study aimed to evaluate the effects of adding Yucca schidigera and zeolite (Clinoptilolite) to feed (super premium and standard) for adult dogs on the apparent indigestibility coefficient of minerals. In the first assessment, 21 dogs were used, with average weight of 12.5kg±1.46 in seven treatments in two periods (super premium diet referred to as control and control with the addition of 125, 250, 375ppm Yucca schidigera and 0.5%, 0.75% and 1.0% zeolite). The second assessment was conducted with standard feed, using 21 experimental plots distributed in three treatments (standard diet referred to as control and control with the addition of 375ppm of Yucca schidigera and 1.0% zeolite). The additives did not affect the acceptability of feed and fecal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Pets; Clinoptilolite.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352013000300042

Use of Adsorbent Biochar from Pequi (Caryocar Brasiliense) Husks for the Removal of Commercial Formulation of Glyphosate from Aqueous Media
Provedor de dados: 52
Autores: Borba,Lana Lima; Cuba,Renata Medici Frayne; Terán,Francisco Javier Cuba; Castro,Martha Nascimento; Mendes,Thiago Augusto.
Abstract This study evaluated the capacity of adsorbent biochar derived from pequi husks to remove glyphosate (commercial formulation) in aqueous medium under three pH conditions (5.5, 7.0 and 8.0). This biochar presented a mean yield of 33.1% ± 2.66% and a high amount of surface particles of small dimensions endowing it with high surface area. The results showed that removal is proportional to pH increase in the range of 5.5 to 8.0. Adsorption assays performed at pH 7 and 8 fitted better to the Langmuir pseudo-first order kinetics model with fast adsorption in the first 15 to 30 minutes. The results for the acidic pH range fit none of the adopted models satisfactorily. The results obtained suggest that adsorbent can be used as an efficient and inexpensive...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Agroindustrial waste; Glyphosate commercial formulation; Biochar; Adsorption.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132019000100603

Adsorption of glyphosate on clays and soils from Paraná State: effect of pH and competitive adsorption of phosphate
Provedor de dados: 52
Autores: 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

Storage of purified biogas (biomethane) at low pressure
Provedor de dados: 52
Autores: Feroldi,Michael; Caroline,Andressa; Borba,Neves, Carlos Eduardo; Arantes,Mabel Karina; José,Alves Helton.
ABSTRACT The global use of fossil energy sources has led to the need to develop technologies capable of mitigating its consequences. One such option is anaerobic biodigestion, which is already scientifically well-established, although the use of its main products (biogas and biomethane) still requires further development before they can be employed in automotive vehicles, largely due to technical issues concerning their storage. The storage of methane using adsorption (Adsorbed Natural Gas - ANG) is a technology that requires less energy and moderate pressures and temperatures. However, the main storage techniques continue to be those that involve high pressures and/or cryogenic temperatures. The present work evaluates the performance of an unprecedented...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Biogas; Vehicle fuel.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132018000200200

Adsorption of natural dyes on clay fixed on polymers
Provedor de dados: 52
Autores: 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

Copper adsorption in tropical oxisols
Provedor de dados: 52
Autores: 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

Zearalenone adsorption capacity of lactic acid bacteria isolated from pigs
Provedor de dados: 58
Autores: Vega,María F.; Dieguez,Susana N.; Riccio,Belén; Aranguren,Sandra; Giordano,Antonio; Denzoin,Laura; Soraci,Alejandro L.; Tapia,María O.; Ross,Romina; Apás,Ana; González,Silvia N.
ABSTRACT The ability to adsorb zearalenone by five strain of lactic acid bacteria was evaluated: four strains of Lactobacillus spp. isolated from pig rectal swabs and one commercial strain (Lactobacillus rhamnosus). Several factors affecting the adsorption capacity were evaluated in order to improve the adsorption of the mycotoxin by bacteria. The stability of the zearalenone-bacteria complex was analyzed. In every case, bacterial adsorption capacity was higher than 40.0%. The strain showing the highest adsorption (68.2%) was selected for the following steps of this research. The adsorption percentages obtained after processing 6.5 and 7.5 mL MRS broth were 57.40% + 3.53 and 64.46% + 0.76, respectively. The stability of zearalenone-bacteria complex was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Zearalenone; Adsorption; Lactic acid bacteria; Lactobacillus; Pigs.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822017000400715

Effect of Quail Litter Biochar on Productivity of Four New Physic Nut Varieties Planted in Cadmium-Contaminated Soil
Provedor de dados: 117
Autores: 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

Continuous Stabilization of Chardonnay with Ion-Exchage Resin: Influence on Protein and Phenolic Profile of Wine
Provedor de dados: 117
Autores: 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

New raw material for activated carbon: I. Methylene blue adsorption on activated carbon prepared from Khaya senegalensis fruits
Provedor de dados: 118
Autores: Gimba,Casmir E; Ocholi,Odike; Egwaikhide,Peter A; Muyiwa,Turoti; Akporhonor,Emmanuel E.
Activated carbons were prepared from Khaya senegalensis fruits. Carbonization and activation temperatures were 500°C and 800°C, respectively, at residence time of 5 min for each process. Activating agents were 1M each of NaCI, KCl, CaCl2, MgCl2.6H2O, Na2CO3 K2CO3 H2SO4, and ZnCl2. Particle size was 125 um and adsorption studies were carried out using methylene blue in aqueous solution as adsórbate through fixed beds in micro columns. Equilibrium data were analyzed using adsorption intensity and capacity parameters from the Freundlich isotherms as well as breakthrough curves. Results were compared with performances of commercial animal charcoal and granular activated carbon. The results suggest that K senegalensis fruits are suitable raw matenals for...
Tipo: Journal article
Palavras-chave: Activation; Adsorption; Carbonization; Isotherm Khaya senegalensis.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202009000100010

Fate of allelochemicals in the soil
Provedor de dados: 65
Autores: Vidal,Ribas Antonio; Bauman,Thomas Trost.
Allelochemicals are compounds released by one plant or plant residues that may have a negative or positive effect on other plant. The importance of allelopathy was extensively explored during the past three decades, with the work concentrating in the extraction and identification of the chemicals, and demonstration of activity in petry dish experiments. These compounds interact in the soil environment similarly as herbicides and are subject to processes of degradation such as microbial degradation, oxidation, and photolysis, and processes of removal or transfer, such as volatilization and adsorption. The objective of this review was to access the fate of allelochemicals in the soil environment to help to find strategies to increase its activity. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Allelopathy; Oxidation; Photolysis; Plant interference; Volatilization.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84781997000200032

Biochar association with phosphate fertilizer and its influence on phosphorus use efficiency by maize
Provedor de dados: 64
Autores: Santos,Sara Ramos dos; Lustosa Filho,José Ferreira; Vergütz,Leonardus; Melo,Leônidas Carrijo Azevedo.
ABSTRACT The use of fertilizers with some degree of protection of the phosphate ions can reduce soil adsorption and increase the absorption by plants, increasing the efficiency of phosphorus (P) fertilization. This study aimed to evaluate the performance of a phosphate fertilizer associated with biochar in granules in a P-fixing soil in a greenhouse experiment. Biochars were produced from two sources of biomass: sugarcane bagasse (SB) and wood sawdust (WS), which were pyrolysed at two temperatures (350 °C and 700 °C). After chemical and physical characterization, the biochar samples were granulated with triple superphosphate (TSP) in a 3:1 ratio (TSP: biochar). The agronomic evaluation of the fertilizers was carried out by two successive maize crops (Zea...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Organic residues; Adsorption; Pyrolysis; Tropical soils.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542019000100202

Removal of copper in cachaças using clays
Provedor de dados: 64
Autores: Duarte,Felipe Cimino; Cardoso,Maria das Graças; Magriotis,Zuy Maria; Santiago,Wilder Douglas; Mendonça,João Guilherme Pereira; Rodrigues,Leonardo Milani Avelar.
Increased production and cachaça consumption has stimulated research regarding its quality. It is known that copper can be harmful to human health when it is in concentrated form in the beverage and is ingested in large amounts. Thus, there is a great concern among researchers and producers about the use of adsorbent substances for the removal of excess copper. The kinetic parameters and the adsorption isotherms for copper on kaolinite were studied to evaluate the physical-chemical quality of the cachaça before and after adsorption. K01, K03 and K04 kaolinites presented a maximum adsorption capacity of 97, 95 and 90%, respectively. The kinetic rates followed the pseudo-first-order model, and the adsorption isotherm was best adjusted to the Freundlich...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Beverage; Kinetic parameters; Isotherms; Adsorption.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542014000400009

Growth of Brachiaria decumbens in Latosol contaminated with copper
Provedor de dados: 64
Autores: Silva,Ilmo Correia; Rocha,Cleonice; Rocha,Mariella Camargo; Sousa,Cleiton Mateus.
ABSTRACT Brachiaria decumbens presents high rusticity, rapid growth, as well as easy implantation and management. The aim of the study is to evaluate the growth of brachiaria in soil contaminated with copper. An experiment following a 3 x 4 factorial design was carried. It comprised three plant ages (30, 45 and 60 days after transplanting) and four copper concentrations (0, 20, 40 and 80 mg of Cu per kg of soil). Plant age and copper concentrations have influenced the main pseudostem length, the number of leaves, as well as the leaf area, chlorophyll (SPAD), fresh and dry shoot matter, root system volume, and fresh and dry root system matter of plants. The lowest dry shoot matter accumulation was found at the concentration 51.24 mg Kg-1. The herein...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Cerrado; Phytoremediation; Heavy metal.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542018000200168