N,N'-diethyl-N,N'-ditolyl-dipicolinamide (ortho)

Abbreviation(s)

Et(o)TDPA

Chemical group

dipicolinamide

Formula

C25H27N3O2 CHON

Molecular mass

401.51 g/mol

Separation factors
Factor Value Conc. Add. ligand Aq. acid Organic diluent Temp. Contact time Additional Ref.
Am/La 16 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Ce 6.8 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Pr 4.8 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Nd 3.4 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Sm 4 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Eu 4.4 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Gd 6 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/La 12.5 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Ce 5.8 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Pr 4.3 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Nd 3.5 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Sm 3.6 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Eu 5 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/Gd 8.3 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [1]
Am/La 700 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Ce 59 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Pm 18 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Nd 8.1 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Sm 1.8 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Eu 1.6 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Gd 4.4 0.01 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/La 530 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Ce 120 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Pm 19 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Nd 8.6 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Sm 2.8 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Eu 2.3 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Gd 3.4 0.01 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/La 185 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Ce 93 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Pm 43 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Nd 18 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Sm 2 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Eu 1 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Am/Gd 1.5 0.01 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min 0.02M hexachlorocobalt dicarbollide [2]
Distribution coefficients
Element Value Conc. Add. ligand Aq. acid Organic diluent Temp. Contact time Additional Ref.
La ≈1.05 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈2.13 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈3.74 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈5.31 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈5.60 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈6.79 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈6.56 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈16.07 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈27.72 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈50.38 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈105.41 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈137.22 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈185.00 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈232.49 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈19.16 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈0.35 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈0.68 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈1.05 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈1.36 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈1.22 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈1.14 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈0.84 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈1.23 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈1.69 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈2.46 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈2.99 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈3.68 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈4.21 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈4.76 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈4.31 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈0.08 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈0.17 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈0.22 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈0.29 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈0.27 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈0.20 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈0.12 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈0.13 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈0.13 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈0.15 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈0.17 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈0.17 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈0.18 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈0.20 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈2.48 0.05 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈4.00 0.075 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈6.13 0.1 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈10.71 0.15 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈18.48 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈1.02 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈4.84 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈18.51 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈47.18 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Am ≈126.36 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈0.02 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈0.08 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈0.35 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈1 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈1.93 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
La ≈3.73 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈0.06 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈0.18 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈0.66 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈2.2 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈4.54 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ce ≈9.1 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈0.075 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈0.23 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈1 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈3.76 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈8.81 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Pr ≈18.2 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈0.09 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈0.29 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈1.37 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈5.49 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈13.7 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Nd ≈32.13 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈0.094 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈0.28 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈1.17 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈5.67 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈22 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Sm ≈91 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈0.064 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈0.2 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈1.1 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈6.64 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈34.2 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Eu ≈1000 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈0.03 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈0.12 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈0.83 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈6.23 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈42.7 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Gd ≈1208 0.2 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈0.03 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈0.13 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈1.21 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈16 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tb ≈220 0.2 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈0.024 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈0.14 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈1.7 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Dy ≈27.4 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈0.023 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈0.15 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈2.42 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Ho ≈48.4 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈0.02 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈0.16 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈3.02 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Er ≈100 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈0.023 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈0.176 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈3.76 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Tm ≈137 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈0.02 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈0.18 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈4.13 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Yb ≈176 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈0.024 0.2 M   HNO3 0.5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈0.2 0.2 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈4.84 0.2 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Lu ≈220 0.2 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 3 min [2]
Th 0.06 0.001 M   HNO3 1 M phenyl trifluoromethyl sulfone (FS-13) 21°C 4 min [3]
Th 0.74 0.001 M   HNO3 2 M phenyl trifluoromethyl sulfone (FS-13) 21°C 4 min [3]
Th 3.8 0.001 M   HNO3 3 M phenyl trifluoromethyl sulfone (FS-13) 21°C 4 min [3]
Th 11 0.001 M   HNO3 4 M phenyl trifluoromethyl sulfone (FS-13) 21°C 4 min [3]
Th 18.8 0.001 M   HNO3 5 M phenyl trifluoromethyl sulfone (FS-13) 21°C 4 min [3]
Th 18.6 0.001 M   HNO3 6 M phenyl trifluoromethyl sulfone (FS-13) 21°C 4 min [3]
References
  1. doi:10.1080/01496390802121636

  2. doi:10.1080/07366299.2012.735528

  3. doi:10.1088/1757-899X/9/1/012068