Effects of temperature and dissolved CO<Subscript>2</Subscript> on the scaling of water in the presence of copper and zinc

In this study, through the method of rapid controlled precipitation (RCP), the influence of temperature and dissolved CO₂ on the scaling capacity of mineral water in the presence of copper and zinc ions was studied in laboratory experiments. The results indicated that with a rise in temperature or concentration of dissolved CO₂, the scaling time of Salvetat water greatly decreased and the rate of precipitation considerably increased; therefore, the minimum dosage of copper or zinc ion for achieving total inhibition of scaling needed to be increased, which would provide better guidance for practical use of metal ions in inhibiting the scaling of drinking water.     

Synthesis of a mesoporous composite material prepared by the self-assembly of mineral liquid crystals

Here we describe the synthesis of a mesoporous composite material using the self-assembly of well defined tubular building blocks obtained from the exfoliation of [Nb6O17(4-)]n sheets.     

Torsion sur des familles de courbes de genre g

We construct here, forl=2g ² +2g+1 or2g ² +3g+1, a family with one parameter of hyperelliptic curves of genusg overQ such that its jacobian has a point of orderl rational overQ(t). Wheng=2 the method allows to construct, forl=17, 19 or 21 a family with one parameter of hyperelliptic curves of genus 2 overQ such that its jacobian has a point of orderl rational overQ(t).