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Disposal of dredged sediments in tropical soils: ecotoxicological effects on ea...

The upper limit concentrations of metals established by international legislations for dredged sediment disposal and soil quality do not take into consideration the properties of tropical soils (generally submitted to more intense weathering processes) on metal availability and ecotoxicity. Aiming to perform an evaluation on the suitability of these threshold values in tropical regions, the ecotoxicity of metal...

Tecnologias da informação e da comunicação. Para um novo enfoque sobre o desenv...

A TV segmentada no Brasil de hoje

Efeitos da hidroterapia no equilíbrio, risco de quedas, medo de cair e qualidad...

Introdução: A Hidroterapia tem sido recomendada para a população idosa, por se apresentar como uma atividade segura, menos propensa a quedas e com boa aceitação e adesão ao tratamento, e que tem sido alvo de várias investigações a nível do equilíbrio e risco de quedas nesta população. Objetivo: Este trabalho pretendeu, avaliar os efeitos de um programa de Hidroterapia no equilíbrio, risco de quedas, medo de cai...

Traumatologia oral numa população de atletas infanto-juvenis : abordagem epidem...

Introdução O futebol é o desporto mais popular no mundo. A frequência e gravidade das lesões no desporto em geral, e no futebol em particular, especialmente as lesões orofaciais deveriam constituir uma preocupação central para todos os intervenientes neste desporto. O lábio superior, o maxilar e os incisivos superiores são, geralmente, as estruturas mais afectadas, as quais podem ser protegidas pelo uso dum pro...

Emprego de sílica gel organicamente modificada e impressa ionicamente para pré-...

The present work purposes the preparation of a silica gel sorbent organically modified with 2-aminoethyl-3-aminobutylmethyldimethoxysilane (AAMDMS) and imprinted with Cu2+ ions by means surface imprinting technique and its use for selective on-line sorbent preconcentration of Cu2+ ions with further UV-VIS spectrophotometric determination by flow injection analysis. The Cu2+-imprinted silica gel, when compared w...

Losartan potassium dissolution test for drug release evaluation in pharmaceutic...

This work describes the development and validation of a dissolution test for 50 mg losartan potassium capsules using HPLC and UV spectrophotometry. A 2(4) full factorial design was carried out to optimize dissolution conditions and potassium phosphate buffer, pH 6.8 as dissolution medium, basket as apparatus at the stirring speed of 50 rpm and time of 30 min were considered adequate. Both dissolution procedure ...

Selective sorbent enrichment of nickel ions from aqueous solutions using a hier...

This study involves the preparation of an ion imprinted organic-inorganic polymer (IIP) for selective sorbent enrichment of Ni2+ from aqueous solutions with further determination by GF AAS. The hybrid polymeric network was prepared from a mixture of 2-aminoethyl- 3-aminobutylmethyldimethoxysilane as functional monomer, and tetraethoxysilane as crosslinking agent, containing Ni2+ and cetyltrimethylammonium bromi...

Silica-alumina-niobia (SiO2/Al2O3/Nb2O5) matrix obtained by the sol-gel process...

In the present work, a new material, SiO2/Al2O3/Nb2O5 (designated as SiAlNb), was evaluated as an adsorbent in a flow injection spectrophotometric method for online preconcentration and determination of trace amounts of Zn2+ ions. The preconcentration method is based on Zn2+ adsorption onto the surface of SiAlNb in alkaline medium (pH 9.0). The elution step is carried out using HNO3 solution, followed by reacti...

Eletrocromatografia capilar: contextualização, estado da arte e perspectivas

Capillary electrochromatography (CEC) is a separation technique in which the mobile phase flow is based on the application of a voltage across a packed capillary, which generates an electroosmotic flow that transports the analytes along the capillary toward the detector. As it combines the separation mechanisms of high-performance liquid chromatography (HPLC) and of capillary electrophoresis (CE), CEC can be co...