Consulta: subjectFacets:"Kinetic"
Registros recuperados: 12
Data/hora: 05/06/2024 18:16:25

Biosorption of uranium from aqueous solutions by nonliving biomass of marinealgae Cystoseira indica
Provedor de dados: 69
Autores: Hassan Khani,Mohammad; Reza Keshtkar,Ali; Meysami,Behrouz; Firouz Zarea,Mohammad; Jalali,Reza.
Biosorption of heavy metals can be an effective process for the removal and recovery of heavy metal ions from aqueous solutions. In this paper uranium biosorption by protonated, Ca-pretreated and non-pretreated Cystoseira indica algae biomass was investigated in a batch system. The results of the kinetic studies showed that the sorption of uranium on protonated and non-pretreated biomass followed pseudo-second order kinetics. The effect of pH on the equilibrium uranium sorption capacity of Cystoseira indica exhibited that highest uptake occurred at pH 4 at a solution with 350 mg/l uranium concentration. At various initial uranium concentrations from 50 to 1000 mg/l, batch sorption equilibrium at 30&amp;ordm;C was reached within 3 hrs and the sorption...
Tipo: Journal article
Palavras-chave: Biosorption; Cystoseira indica; Equilibrium; Kinetic; Marine algae; Uranium.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000200003

Effects of biosorption parameter: kinetics, isotherm and thermodynamics for Ni(II) biosorption from aqueous solution by Circinella sp.
Provedor de dados: 69
Autores: Alpat,Senol; Alpat,Sibel Kilinç; Çadirci,Bilge Hilal; Özbayrak,Özge; Yasa,Ihsan.
Circinella sp. was employed as a biosorbent for removal of Ni(II) from aqueous solution. The biosorption kinetics and isotherms were investigated. The effect of several parameters, such as biosorbent dosage, contact time, initial concentration, pH and temperature, on biosorption process was evaluated. The kinetic studies indicated that the biosorption followed pseudo-second order kinetic model. Biosorption behaviour of Ni(II) on Circinella sp. was expressed by both Langmuir and Freundlich isotherms. The equilibrium data fit better to the Langmuir model compared to the Freundlich model in concentration range studied (1.0-3.0 mM). The thermodynamic parameters (&amp;#916;G0, &amp;#916;H0 and &amp;#916;S0) were also determined, and it was found that the Ni(II)...
Tipo: Journal article
Palavras-chave: Biosorption; Circinella sp; Equilibrium; Kinetic; Nickel.
Ano: 2010
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582010000500004

Performance of an anaerobic-aerobic reactor and kinetic study of organic matter removal of cattle slaughterhouse effluent
Provedor de dados: 70
Autores: Kreutz,Cristiane; Passig,Fernando H.; Carvalho,Karina Q. de; Mees,Juliana B. R.; Gomes,Simone D.
This paper sought to evaluate the behavior of an upflow Anaerobic-Aerobic Fixed Bed Reactor (AAFBR) in the treatment of cattle slaughterhouse effluent and determine apparent kinetic constants of the organic matter removal. The AAFBR was operated with no recirculation (Phase I) and with 50% of effluent recirculation (Phase II), with θ of 11h and 8h. In terms of pH, bicarbonate alkalinity and volatile acids, the results indicated the reactor ability to maintain favorable conditions for the biological processes involved in the organic matter removal in both operational phases. The average removal efficiencies of organic matter along the reactor height, expressed in terms of raw COD, were 49% and 68% in Phase I and 54% and 86% in Phase II for θ of 11h and 8h,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Kinetic; Cattle slaughterhouse; Combined treatment system.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162014000200015

Пeрвичная продукция и биотический баланс морских экосистем
Provedor de dados: 13
Autores: Чмыр, В. Д.
Рассматривается кинетика вновь образованного в процессе фотосинтеза органического вещества фитопланктона, выедаемого консументами за время экспозиции  при определении первичной продукции радиоуглеродным методом. Дана оценка воздействия консументов на величину измеряемой первичной продукции и возможных последствий для расчетов баланса вещества и энергии экосистем морской пелагиали.
Tipo: Journal Contribution
Palavras-chave: Первичная продукция; Биотический баланс; Экосистемы; Фитопланктон; Кинетика; Primary production; Phytoplankton; Kinetic; Biotic balance; Ecosystems Kinetics Primary production Ecosystems Phytoplankton Primary production Ecosystems Phytoplankton http://aims.fao.org/aos/agrovoc/c_34329 http://aims.fao.org/aos/agrovoc/c_2482 http://aims.fao.org/aos/agrovoc/c_13344.
Ano: 2002
URL: http://repository.ibss.org.ua/dspace/handle/99011/400

Dissolved inorganic nitrogen uptake by intertidal microphytobenthos: nutrient concentrations, light availability and migration
Provedor de dados: 5
Autores: Longphuirt, Sorcha Ni; Lim, Jae-hyun; Leynaert, Aude; Claquin, Pascal; Choy, Eun-jung; Kang, Chang Keun; An, Shu.
The importance of intertidal flats as areas of nitrogen filtering has become increasingly apparent in recent times. TO understand fully the cycling of this nutrient. in these areas of high metabolic activity, it is necessary to elucidate the influence of microphytobenthos (MPB) on stocks of ammonium and nitrate in surface areas. In this study, we aimed to quantity nitrogen uptake and relate it to the in Situ concentrations and environmental conditions to which MPB are exposed. In an estuarine system on the Korean Peninsula, we conducted kinetic experiments using N-15 stable isotopes and core sampling over the tidal cycle to determine the temporal evolution of porewater nutrient concentrations and the migration of MPB. The results revealed a range of K-s...
Tipo: Text
Palavras-chave: N 15 stable isotope; Porewater; Microphytobenthos; Kinetic; Nitrogen.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6622.pdf

Purification de la chitine par hydrolyse enzymatique à partir de coproduits de crevette Penaeus vannamei. Caractérisations des produits et optimisation du procédé
Provedor de dados: 5
Autores: Le Roux, Karine.
The objective of this study was to optimize the extraction of chitin by acid proteolysis. The novelty of the method is based on the stabilization of pH by the balance between substrate composition and the acid solvent. This principle allows a simultaneous demineralization and deproteinization, the two main reactions associated with the purification of chitin. To evaluate the performance of this purification, the composition of the substrate and products was characterized. Different methods of quantification of chitin and proteins have been compared. As traditional assays were not satisfaying, a direct method of amino acids determination by gaz chromatography was selected to estimate the amount of protein. The estimate of chitin amount was based on indirect...
Tipo: Text
Palavras-chave: Coproduits de crustacés; Hydrolyse enzymatique; Protéolyse; Chitine; Extraction; Cinétique; Déminéralisation; Déprotéinisation; Crustacean by-products; Enzymatic hydrolysis; Proteolysis; Chitin; Extraction; Kinetic; Demineralization; Deproteinization.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00087/19828/17470.pdf

Application of PFC3D to simulate a planetary ball mill
Provedor de dados: 111
Autores: Chen, Ying; Guzman, Leno; Potter, Simon; Khan, Majibur.
Planetary ball mill is a versatile machine which has been used for grinding different types of materials for size reduction and lately for hemp decortication. PFC3D, software employing the discrete element method (DEM), was used to simulate the power and energy requirement of grinding hemp for fibre using a planetary ball mill. The simulation was facilitated through a series of hemp grinding tests using the planetary ball mill to examine the power draw of the mill. The test results identified that grinding speed had a significant effect on the power draw of the mill. The power draw data were used to calibrate the discrete element parameters for different grinding speeds. Using the calibrated parameters, one was able to predict the kinetic energy and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Agricultural machinery; Bioprocessing PFC3D; Discrete element model (DEM); Hemp; Planetary ball mill; Power; Energy; Kinetic; Friction.
Ano: 2015
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2986

Quantification of browning kinetics and colour change for quince (Cydonia oblonga Mill.) exposed to atmospheric conditions
Provedor de dados: 111
Autores: Guiné, Raquel P.F.; Barroca, Maria João.
Because quince is a fruit that shows a very strong tendency for developing an intense browning when exposed to air, even though for short periods of time, the aim of this work was to evaluate the kinetics of colour change for quince exposed to atmospheric air at ambient temperature over a period of 2 hours. The quince was cut into slices that were left exposed to air, and colour measurements were done right after cutting and every five minutes, using a tristimulus colorimeter measuring the CIELab coordinates, L*, a* and b*.  The results confirmed that quince suffers a high degree of browning, with total colour difference increasing strongly from 0 to 30 and browning index increasing from 50 to near 140. Furthermore, the major colour changes occurred during...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Food industry; Food properties; Food engineering Quince; Browning; Kinetic.
Ano: 2014
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/2892

Evaluation of cefepime kinetic variables and milk production volume in goats
Provedor de dados: 45
Autores: Rule,R.; Lacchini,R.; Mordujovich,P.; Antonini,A.
Avaliaram-se as variáveis cinéticas da cefepime e a produção de leite de cabras após a administração parenteral (intravenosa e intramuscular) de cefepime, com e sem reação inflamatória na região implantada. Dez cabras em lactação, implantadas com caixas de material sem reação imunológica para colher o fluido de tecido (FT) foram usadas em dois experimentos. No primeiro a aplicação de cefepime foi feita na primeira semana após a implantação e no segundo na oitava semana. Na primeira semana após a implantação observou-se elevação dos níveis de proteína no fluido do tecido após uma simples dose de 20mg/kg de cefepime via endovenosa ou intramuscular. Amostras do sangue e do leite foram obtidas e as variáveis cinéticas foram avaliadas.
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Cefepime; Goat; Kinetic; Milk; Production.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352004000100018

A model on biological flow of phosphorus in growing pigs
Provedor de dados: 45
Autores: Lopes,J.B.; Moreira,J.A.; Kebreab,E.; Vitti,D.M.S.S.; Abdalla,A.L.; Crompton,L.A.; France,J.
Ten crossbred barrows weighting 20kg were allocated in five groups fed and on diets consisted of different total phosphorus (P) levels: 0.30%, 0.40%, 0.51%, 0.65%, and 0.73%. The animals were intravenously injected 7.4MBq of radioactive P (32P) and after seven days they were slaughtered for further analysis. The evaluated parameters were intake, excretion, specific activities, and flow of P in compartments (1-gut, 2-blood, 3-bone, and 4-soft tissue). Besides fecal losses, the kidneys played an import role in P regulation. The flows of P from tissue and gut to the blood were affected by P intake.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pig; Metabolism; Balance; True absorption; Radio-phosphorus; Kinetic.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352009000300024

Characteristics of Immobilized Urease on Grafted Alginate Bead Systems
Provedor de dados: 52
Autores: Danial,Enas N.; Hamza,Amal H.; Mahmoud,Rasha H.
This study evaluated the biological importance of immobilized urease enzyme over the free urease. The support material used for urease immobilization was alginate. Generally, the immobilization of urease in alginate gel showed a marked increase in Km and Vmax. However, the immobilized urease showed higher thermal stability than that of free enzyme. The rate of thermal inactivation of the immobilized enzyme decreased due to entrapment in gel matrix. Also, the activity of the immobilized urease was more stable in retention than that of the free enzyme during the storage in solution, although the activity of the immobilized enzyme was lower in comparison with the free enzyme. A stable immobilized system and long storage life are convenient for applications...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Urease; Immobilization; Kinetic; Reusability; Storage stability.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132015000200147

Determination of kinetic parameters of an upflow anaerobic sludge blanket reactor (uasb), treating swine wastewater
Provedor de dados: 64
Autores: Matangue,Mario Tauzene Afonso; Campos,Claudio Milton Montenegro.
This research aimed to estimate the kinetic parameters of a UASB reactor treating swine wastewater from farming. The system consisted of: a degritter with a triangular-notch weir in order to measure the flow; a static sieve; an acidification/equalization tank (AET); ABR and UASB reactors; a settling tank; two infiltration ponds and a greenhouse for fertirrigation. The hydraulic retention times (HRT) adopted for the UASB reactor, were: 8.0; 9.6; 8.4; 6.0 and 4.8 hours. The operational temperature was 23.4º C±1.5º C. The analyzed physical-chemical parameters were temperature COD (total and filtered), BOD (total and filtered), total volatile solids (affluent, effluent and of the reactor's profile sludge), flow rate and nutrients (N and P). The kinetic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Swine wastewater; Kinetic; UASB reactor.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542011000600022