The Commission has asked EFSA to update the previous opinion expressed by the Scientific Committee on Veterinary Measures Relating to Public Health (SCVPH) on 14-15 April 2003 with regard to the toxicological risks to public health from possible reaction products (e.g. semicarbazide) of chlorine dioxide, acidified sodium chlorite, trisodium phosphate and peroxyacids when applied on poultry carc...

Introduction: The Bosumtwi Impact Crater in Ghana, Africa (6°32’N, 1°25’W) is a large complex crater. The crater is 10.5 km in diameter, with a central uplift 2 km in diameter. It is the source of the Ivory Coast Tektite field, found to the southwest of the crater over 200 km away. This study investigates the mineralogy, the petrology, and the geochemistry of drill core samples taken near the c...

Mineral dust supplied to remote ocean regions stimulates phytoplankton growth through delivery of micronutrients, notably iron (Fe). Although attention is usually paid to Fe (hydr)oxides as major sources of available Fe, Fe-bearing clay minerals are typically the dominant phase in mineral dust. The mineralogy and chemistry of clay minerals in dust particles, however, are largely unknown. We con...

Abst rac t -Oxygen isotopic compositions were determined for coexisting mixed-layer serpentine-chlorite (Sp-Ch) and illite-smectite (I-S) from 5 Tuscaloosa Formation sandstone cores sampled between 1937 and 5470 m burial depth. High gradient magnetic separation (HGMS) was used to concentrate Sp-Ch and I-S from the <0.5 p~m fraction of each core sample into fractions with a range in the Sp-Ch : ...

A (linear) stability analysis of planar reaction fronts to transverse perturbations is considered for systems based on cubic autocatalysis and a model for the chlorite-tetrathionate reaction. Dispersion curves (plots of the growth rate sigma against a transverse wave-number k) are obtained. In both cases it is seen that there is a nonzero value D0 of D (the ratio of the diffusion coefficients o...