[1] Chemical Engineering Department,
[2] Universitat Politècnica de Catalunya,undefined
[3] E.T.S.E.I.B.,undefined
[4] Diagonal 647,undefined
[5] E-08028 Barcelona,undefined
[6] Spain,undefined
[7] On leave from: Department of Analytical Chemistry,undefined
[8] Tirana University,undefined
[9] Tirana,undefined
[10] Albania,undefined
[11] Analytical Chemistry Department,undefined
[12] Universitat de Barcelona,undefined
[13] Martí y Franqués 1,undefined
[14] E-08028 Barcelona,undefined
[15] Spain,undefined