It is possible, by conducting fly ash leaching tests at two different water:ash ratios, to determine whether or not the concentration of an element in the leachate is controlled by mineral solubility. If a mineral solubility control exists, the element's concentration can be readily predicted with chemical equilibria models. On the other hand, if the concentration of an element is controlled by the rate of release from ash particles, more sophisticated hydrochemical transport models are required. The conduct of leach tests on waste materials at two different water:solid ratios is recommended as a general procedure in waste management. In this study, the concentration of Na, K, Cl, B, and Cr(VI) in Lakeview fly ash leachate were found not to be controlled by mineral solubility. Therefore, the solution concentrations of these elements will be influenced by the relative amounts of water to ash in a mix, and the flux of these elements from hydrating primary ash particles with time. Evidence of solubility control was found for Ca, Sr, SO4 , Al, Si, As(V), and Se in leachate solutions. Calcium and SO 4 concentrations were controlled by gypsum solubility; Sr, probably by a (Ba,Sr)SO4 solid solution; Al and Si, by a hydrous aluminosilicate, probably allophane; Mg, by a hydrous magnesium silicate like sepiolite; and As, by either a ferric metal arsenate or strongly associated with a ferric oxide phase. The probable control on Se concentrations is through coprecipitation in secondary sulphate mineral precipitates.

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Ursolic .acid has been evaluated for its choleretic, anticholestatic and hepatoprotective activities in rats. It produced a dose-dependent (5-20 mg/kg) choleretic effect. Significant anticholestatic activity (27.9-100%) was observed against paracetamol (2.0 glkg) induced cholestasis. The compound also showed a marked hepatoprotective activity against paracetamol and galactosamine (800 mg/kg) induced hepatotoxicity by reversing the altered values in viability of the isolated hepatocytes and the altered biochemical liver and serum parameters. The activity of ursolic acid compared well with the known hepatoprotective drug, silymarin.

Volatile constituents of Vitex negundo leaves growing in Dehra Dun (India) were analysed by gas chromatography-mass spectrometry (GC-MS) and showed the presence of sixty-six compounds. Such a study has not been done earlier on the Indian oil. Thirty-five compounds, constituting 74.96% of the oil, were identified. The main compounds are viridiflorol (19.55%), beta-caryophyllene (16.59%), sabinene (12.07%), 4-terpineol (9.65%), gamma-terpinene (2.21%), caryophyllene oxide (1.75%), 1-oceten-3-ol (1.59%), and globulol (1.05%). Viridiflorol is being reported for the first time in the oil of Vitex species.

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