Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1890-1891.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1876-1879.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1900-1901.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1892-1893.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1891-1892.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1888-1889.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1898-1899.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1899-1900.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1905-1906.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1889-1890.

Rapport au Président de la République sur les opérations des banques coloniales ... / Commission de surveillance des banques coloniales

1886-1887.

Design and evaluation of a continuous flow, integrated nebulizer-hydride generator for flame atomic absorption spectrometry

An evaluation of the performance of a continuous flow hydride generator-nebulizer for flame atomic absorption spectrometry was carried out. Optimization of nebulizer gas flow rate, sample acid concentration, sample and tetrahydroborate uptake rates and reductant concentration, on the As and Se absorbance signals was carried out. A hydrogen-argon flame was used. An improvement of the analytical sensitivity relative to the conventional bead nebulizer used in flame AA was obtained (2 (As) and 4.8 (Se) µg L-1). Detection limits (3σb) of 1 (As) and 1.3 (Se) µg L-1 were obtained. Accuracy of the method was checked by analyzing an oyster tissue reference material.

Determination of Cd and Pb in fuel ethanol by filter furnace electrothermal atomic absorption spectrometry

A method was developed for quantification of Cd and Pb in ethanol fuel by filter furnace atomic absorption spectrometry. Filter furnace was used to eliminate the need for chemical modification, to stabilize volatile analytes and to allow the application of short pyrolysis step. The determinations in samples were carried out against calibration solutions prepared in ethanol. Recovery tests were made in seven commercial ethanol fuel samples with values between 90 and 120%. Limits of detection were 0.1 µg L-1 for Cd and 0.3 µg L-1 for Pb. Certified water samples (APS 1071, APS 1033, NIST 1643d, NIST 1640) were also used to evaluate accuracy and recoveries from 86.8% to115% were obtained.

On-line preconcentration system using a microcolumn packed with Alizarin Red S-modified alumina for zinc determination by flame atomic absorption spectrometry

A simple and sensitive on-line flow injection system for determination of zinc with FAAS has been described. The method is based on the separation and preconcentration of zinc on a microcolumn of immobilized Alizarin Red S on alumina. The adsorbed analyte is then eluted with 250 µL of nitric acid (1 mol L-1) and is transported to flame atomic absorption spectrometer for quantification. The effect of pH, sample and eluent flow rates and presence of various cations and anions on the retention of zinc was investigated. The sorption of zinc was quantitative in the pH range of 5.5-8.5. For a sample volume of 25 mL an enrichment factor of 144 and a detection limit (3S) of 0.2 µg L-1 was obtained. The precision (RSD, n=7) was 3.0% at the 20 µg L-1 level. The developed system was successfully applied to the determination of zinc in water samples, hair, urine and saliva.

Ion pair-dispersive liquid-liquid microextraction of trace amount of rhodium ion in water and road dust samples prior to flame atomic absorption spectrometry determination

A simple ion pair-dispersive liquid-liquid microextraction method was proposed for preconcentration trace amounts of rhodium. An ion association complex of RhCl4- and tetradecyldimetylbenzylamonium was extracted into cholorobenzene. The volume and the type of extractive and dispersive solvents, the extraction time and the pH of the aqueous solutions were optimized. The calibration curve was linear in the range of 0.6-500 ng mL-1 of rhodium. The limit of detection was 0.10 ng mL-1 in initial solution and preconcentration factor was 40. The proposed method was successfully applied to the extraction and determination of rhodium in road dust and water samples.