Field determination of thallium in water

A simple, selective, and sensitive field procedure for the spectrophotometric determination of thallium in water is described. The preconcentration is carried out by extracting the chlorothallate ion-pair complex of a cationic surfactant, i.e. CTAB or CPC, with toluene. The extract is reacted with a basic dye, i.e. brilliant green (BG). The molar absorptivity of the complexes is in the range of (1.63–1.70)×10⁵ 1 mole^–1 cm^–1 at the absorption maximum of 640 nm. The detection limit is 5 ng ml^–1 Tl in water. None of the tested metal ions upto certain levels interfered with the determination. It is reproducibly applicable to the field analysis of Tl in water samples containing upto 20 ppb.     

Field determination of iodide in water

A simple, fast and sensitive spectrophotometric method for the quantification of iodine and iodide in waters is described. Firstly iodide has been oxidised by sodium nitrite to iodine in HCl medium and the resulting I₂Cl^– has been preconcentrated into toluene. This can be subsequently determined in the extract with brilliant green. A ten-fold preconcentration is obtained, the molar absorptivity is (4.2×10⁴) I mol^–1 cm^–1 at 635 nm. A detection limit of 4 ng/ml iodide in water can be reached. The effect of common anions and cations have been investigated. The method has been applied to the determination fo free iodine, total iodine and iodide in river, pond and well water.     

Fibrinolytic activity of kaempferol isolated from the fruits of Lagenaria siceraria (Molina) Standley

This study was undertaken to isolate a flavonol, kaempferol, from the fruits of Lagenaria siceraria (bottle gourd) as a sole compound and to explore the fibrinolytic potential of the methanolic extract of the fruits of L. siceraria and the isolated compound using their in vitro activity. The fibrinolytic activity in terms of percentage of plasma clot liquefaction was determined by plasma clot lysis at 37°C in 24?h. The fibrinolytic activity of both substances was compared to the well-known thrombolytic agent streptokinase (30,000?IU). The percentage of fibrinolytic activity of the extract and isolated compound were found to be 54.72?±?0.7210 and 77.37?±?1.3010, respectively. Streptokinase was considered as the standard fibrinolytic enzyme for comparative purposes and had 91.46?±?0.7625% fibrinolytic activity. The conclusion drawn in our study after testing the hypothesis by experimental procedures is that in vitro fibrinolytic activity on plasma clots is an inherent property of kaempferol isolated from the fruits of L. siceraria, and its comparison with streptokinase is a new aspect for further study.     

ChemInform Abstract: On Compound Formation of M′O:M2O3. Part 11. Crystal Structure of BaIn2O4.

Single crystals of the title compound, obtained from a melt after reacting intimate mixtures of BaCO₃ and In₂O₃ at 840 °C (12 h), belong to the monoclinic space group P2₁/a with Z=16.     

ChemInform Abstract: Boron Occupied Condensed Clusters in Ta5Ge3By (y ≈ 0.7).

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