Sorbents
Mostrando 13-24 de 41 artigos, teses e dissertações.
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13. Development of a Multiresidue Method for Pesticide Analysis in Drinking Water by Solid Phase Extraction and Determination by Gas and Liquid Chromatography with Triple Quadrupole Tandem Mass Spectrometry
In this work, a method for multiclass determination of 70 pesticides residues with different properties in drinking water using solid phase extraction (SPE) with polymeric sorbent and determination by gas and liquid chromatography coupled to tandem mass spectrometry (GC-MS/MS and LC-MS/MS) was developed and validated. Different sample volumes, sorbents and e
J. Braz. Chem. Soc.. Publicado em: 2015-10
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14. Synthesis of polycationic bentonite-ionene complexes and their benzene adsorption capacity
The purpose of this work was to structurally modify clays in order to incorporate water-insoluble molecules, such as petroleum hydrocarbons. The potential for ion exchange of quaternary ammonium salts was studied, which revealed their ability to interact with anions on the cationic surface, for environmental applications of the material. Ionenes, also known
Polímeros. Publicado em: 2015-04
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15. NOVO SORVENTE DE HIDROFOBICIDADE REDUZIDA PARA EXTRAÇÃO EM FASE SÓLIDA: PREPARAÇÃO E CARACTERIZAÇÃO
C18 chemically bonded sorbents have been the main materials used in solid phase extraction (SPE). However, due their high hydrophobicity some hydrophobic solutes are strongly retained leading to the consumption of larger quantities of organic solvent for efficient recoveries. This work presents a sorbent with lower hydrophobicity but similar selectivity to t
Quím. Nova. Publicado em: 2015-02
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16. Retention of carbamate pesticides by different surfactant-modified sorbents: a comparative study
Diferentes sorventes sólidos modificados com surfactantes foram investigados comparativamente para a retenção de pesticidas carbamato em solução aquosa. Três sorventes modificados, incluindo alumina tratada com dodecil sulfato de sódio (SDS), sílica revestida com brometo de cetil trimetil amônio (CTAB) e zeólita revestida com CTAB foram preparados
J. Braz. Chem. Soc.. Publicado em: 2014-09
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17. Platinum uptake from chloride solutions using biosorbents
Present work investigates platinum uptake from synthetically prepared, dilute platinum-bearing solutions using biomass residues, i.e. pistachio nut shell and rice husk, which are abundant in Turkey, and provides a comparison between these two biosorbents. Effects of the different uptake parameters, sorbent dosage, contact time, temperature and pH of solution
Mat. Res.. Publicado em: 28/01/2013
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18. DESENVOLVIMENTO E VALIDAÇÃO DE MÉTODO ANALÍTICO POR DISPERSÃO DA MATRIZ EM FASE SÓLIDA E CROMATOGRAFIA EM FASE GASOSA ACOPLADA A ESPECTROMETRIA DE MASSAS PARA DETERMINAÇÃO DE PESTICIDAS EM AMOSTRAS DE OVOS DE GALINHA (GALLUS GALLUS DOMESTICUS). / DEVELOPMENT AND VALIDATION OF ANALYTICAL METHOD FOR SCATTERING MATRIX SOLID PHASE AND GAS CHROMATOGRAPHY COUPLED TO A MASS SPECTROMETRY DETERMINATION OF PESTICIDES IN SAMPLES OF CHICKEN EGGS (GALLUS GALLUS DOMESTICUS).
The eggs are of great nutritional value. Its biochemical composition indicates the source of proteins, lipids, vitamins and minerals. However, undesirable chemical compounds can form part of this constitution. The pesticides, when applied irregularly, can represent a serious health risk to consumers if detected above the maximum residue limits, can be identi
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/07/2012
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19. Characterization of Brazilian Bentonite Organoclays as sorbents of petroleum-derived fuels
This work focused on preparing and characterizing Brazilian bentonite clay through the use of quaternary ammonium salt so as to apply it as a sorbent for petroleum-derived fuels. Bentonite clay was organophilizated by the intercalation of quaternary ammonium salts such as cetyl-pyridinium chloride and benzalkonium chloride. The resulting materials were chara
Materials Research. Publicado em: 24/02/2012
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20. MÉTODOS INDIVIDUAL E MULTIRRESIDUAL PARA DETERMINAÇÃO DE PESTICIDAS EM GRÃOS E DERIVADOS POR GC-PFPD, GC-ITD-MS E LC-MS/MS / SINGLE AND MULTI-RESIDUE METHODS FOR PESTICIDE ANALYSIS IN GRAINS AND DERIVATES BY GC-PFPD, GC-ITD-MS AND LC-MS/MS
Due to the complexity of grains like soybean, corn and rice, and the very low pesticide concentration expected for these samples, it is really necessary to develop efficient and reliable analytical methods to identify and quantify their residues. The possibility to perform the determination of a large number of pesticides in just a single chromatographic ana
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 29/08/2011
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21. AdsorÃÃo de MolÃculas Sulfuradas AromÃticas em Adsorventes Mesoestruturados à Base de SÃlica. / Adsorption of aromatic sulfur molecules on mesostructured silica adsorbents.
The demand of a larger control in the emission of pollutants from automobiles, with a reduction in the emission of sulfur, has led to an intense research effort on techniques of sulfur removal from fuels. In the last few years, adsorption is thought to be a suitable polishing technique to achieve a deep desulfurization of streams from hydrodesulfurization (H
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 22/02/2011
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22. FBC desulfurization process using coal with low sulfur content, high oxidizing conditions and metamorphic limestones
A metamorphic limestone and a dolomite were employed as SO2 sorbents in the desulfurization of gas from coal combustion. The tests were performed in a fluidized bed reactor on a bench and pilot scale. Several parameters such as bed temperature, sorbent type, and sorbent particle size at different Ca/S molar ratios were analyzed. These parameters were evaluat
Publicado em: 2011
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23. Aplicação de polissiloxanos imobilizados sobre sílica como fase estacionária e como sorvente na determinação de agrotóxicos em água e caldo de cana / Application of polysiloxanes immobilized on silica as stationary phases and as sorbents in the determination of agrotoxics in water and sugar cane juice
Neste trabalho verificou-se a potencialidade de uso de sorventes e fases estacionárias (FE), obtidos a partir da sorção e/ou imobilização do polímero poli(metiloctilsiloxano) (PMOS) sobre suportes de sílica Kromasil utilizando tamento térmico, na separação, quantificação e validação de uma metodologia para análise de agrotóxicos em amostras d
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/06/2010
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24. DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE RESÍDUOS DE PESTICIDAS EM ALFACE (Lactuca sativa L.) PRODUZIDA EM SISTEMA CONVENCIONAL / DEVELOPMENT OF METHODS FOR DETERMINATION OF RESIDUES OF PESTICIDES IN LETTUCE (Lactuca sativa L.) PRODUCED IN CONVENTIONAL SYSTEM
Lettuce (Lactuca sativa) has a great, being mainly consumed in natura. In order to ensure greater productivity, pesticides from different chemical classes have been used to improve its production. Although these pesticides bring benefits, increasing agricultural production, their toxicity should be considered. As for this reasor it is necessary to have effec
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/02/2010