Tracing geochemical sources and health risk assessment of uranium in groundwater of arid zone of India

Water quality degradation and metal contamination in groundwater are serious concerns in an arid region with scanty water resources. This study aimed at evaluating the source of uranium (U) and potential health risk assessment in groundwater of the arid region of western Rajasthan and northern Gujarat. The probable source of vanadium (V) and fluorine (F) was also identified. U and trace metal concentration, along with physicochemical characteristics were determined for 265 groundwater samples collected from groundwater of duricrusts and palaeochannels of western Rajasthan and northern Gujarat. The U concentration ranged between 0.6 and 260 μg L−1 with a mean value of 24 μg L−1, and 30% of samples surpassed the World Health Organization’s limit for U (30 μg L−1). Speciation results suggested that dissolution of primary U mineral, carnotite [ K2(UO2)2(VO4)2·3H2O] governs the enrichment. Water–rock interaction and evaporation are found the major hydrogeochemical processes controlling U mineralization. Groundwater zones having high U concentrations are characterized by Na–Cl hydrogeochemical facies and high total dissolved solids. It is inferred from geochemical modelling and principal component analysis that silicate weathering, bicarbonate complexation, carnotite dissolution, and ion exchange are principal factors controlling major solute ion chemistry. The annual ingestion doses of U for all the age groups are found to be safe and below the permissible limit in all samples. The health risk assessment with trace elements manifested high carcinogenic risks for children

An empirical correlation for solvent selectivity factor

361-362<span style="font-size:11.0pt;line-height:115%; font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;mso-fareast-font-family:="" "times="" new="" roman";mso-fareast-theme-font:minor-fareast;mso-hansi-theme-font:="" minor-latin;mso-bidi-font-family:"times="" roman";mso-ansi-language:en-us;="" mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">An empirical formulation modifying the Nernst equation to incorporate the selectivity factor, β<span style="font-size:11.0pt; line-height:115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:"times="" new="" roman";mso-fareast-theme-font:minor-fareast;="" mso-hansi-theme-font:minor-latin;mso-bidi-font-family:arial;mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">, is tested with eighteen systems taken from literature to assess its reliability in correlating the LLE data. This simple equation relates the selectivity factor to the ratio of the mass of the solvent to that of the diluents in the solvent phase. The correlation coefficient is almost unity for all the systems. The value of the intercept, In(A), <span style="font-size:11.0pt; line-height:115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:"times="" new="" roman";mso-fareast-theme-font:minor-fareast;="" mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">in the modified Nernst equation, In<span style="font-size:11.0pt; line-height:115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:"times="" new="" roman";mso-fareast-theme-font:minor-fareast;="" mso-hansi-theme-font:minor-latin;mso-bidi-font-family:arial;mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">(β<span style="font-size:11.0pt; line-height:115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:"times="" new="" roman";mso-fareast-theme-font:minor-fareast;="" mso-hansi-theme-font:minor-latin;mso-bidi-font-family:arial;mso-ansi-language:="" en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">)= B In (XBB/XAB)+ In (A) <span style="font-size:11.0pt; line-height:115%;font-family:" calibri","sans-serif";mso-ascii-theme-font:minor-latin;="" mso-fareast-font-family:"times="" new="" roman";mso-fareast-theme-font:minor-fareast;="" mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="">is found to be in direct proportion with solvent selectivity. The equation is also found effective in predicting the salt effect in salt containing ternary liquid systems.</span

Experiments and ANFIS modelling for the biodegradation of penicillin-G wastewater using anaerobic hybrid reactor

The performance of an anaerobic hybrid reactor (AHR) for treating penicillin-G wastewater was investigated at the ambient temperatures of 30-35°C for 245days in three phases. The experimental data were analysed by adopting an adaptive network-based fuzzy inference system (ANFIS) model, which combines the merits of both fuzzy systems and neural network technology. The statistical quality of the ANFIS model was significant due to its high correlation coefficient R2 between experimental and simulated COD values. The R2 was found to be 0.9718, 0.9268 and 0.9796 for the I, II and III phases, respectively. Furthermore, one to one correlation among the simulated and observed values was also observed. The results showed the proposed ANFIS model was well performed in predicting the performance of AHR. © 2011 Elsevier Ltd

Biosynthesis of poly (3-hydroxybutyrate) from cheese whey using <i>Azotobacter vinelandii</i>

68-71Poly (3-hydroxybutyrate) [P(3HB)] is a homopolymer of 3-hydroxy butyrate and is the most widespread and best characterized member of the polyhydroxy-alkanoates (PHAs). Eventhough, P(3HB) has been recognized as a good candidate for biodegradable plastics, their high price compared with conventional pl as tics has limited their use in a wide range of applications. Azotobacter vinelandii (MTCC 124*) was used for the studies because it is able to utilize sucrose, which suggests a cheap carbon source such as cheese whey. The cost of carbon substrate significantly affected the overall economics in large scale production. Tn order to reduce the cost of production, waste whey from cheese making industry is used as a substrate. The effect of different nitrogen sources on the production of P(3HB) was studied. Bacterial peptone gives the maximum production of 1.44 g P(3 HB)L-1 with an incubation time of 48 h. The other effects such as substrate concentration, inoculums size and the environmental condition such as pH are also studied. It was observed that by increasing the inoculum size the time of incubation can be reduced considerably. Productivity of 0.03 g L-1 h-1 was obtained while a maximum productivity of 0.008 g L-1 h-1 has been reported by using l% cheese whey l. Leudeking-Piret kinetic parameters are determined. The result shows that P(3HB) production kinetics may be non-growth associated