@article{bhardwaj_sharma_jain_aggarwal_2012, title={DEVELOPMENT OF ANODIC STRIPPING VOLTAMMETRY FOR THE DETERMINATION OF PALLADIUM IN HIGH LEVEL NUCLEAR WASTE}, volume={44}, ISSN={["1738-5733"]}, DOI={10.5516/net.06.2011.060}, abstractNote={Deposition potential, deposition time, square wave frequency, rotation speed of the rotating disc electrode, and palladium concentration were studied on a Glassy Carbon Electrode (GCE) in 0.01M HCl for the determination of palladium in High Level Nuclear Waste (HLNW) by anodic stripping voltammetry. Experimental conditions were optimized for the determination of palladium at two different, 10 -8 and 10 -7 M, levels. Error and standard deviation of this method were under 1% for all palladium standard solutions. The developed technique was successfully applied as a subsidiary method for the determination of palladium in simulated high level nuclear waste with very good precision and high accuracy (under 1 % error and standard deviation).}, number={8}, journal={NUCLEAR ENGINEERING AND TECHNOLOGY}, author={Bhardwaj, T. K. and Sharma, H. S. and Jain, P. C. and Aggarwal, S. K.}, year={2012}, month={Dec}, pages={939–944} }
 @article{bhardwaj_mclaughlin_levy_2010, title={Depositional seals in polyacrylamide-amended soils of varying clay mineralogy and texture}, volume={10}, ISSN={["1439-0108"]}, DOI={10.1007/s11368-010-0198-2}, number={3}, journal={JOURNAL OF SOILS AND SEDIMENTS}, author={Bhardwaj, Ajay K. and McLaughlin, Richard A. and Levy, Guy J.}, year={2010}, month={Apr}, pages={494–504} }
 @article{bhardwaj_mclaughlin_shainberg_levy_2009, title={Hydraulic Characteristics of Depositional Seals as Affected by Exchangeable Cations, Clay Mineralogy, and Polyacrylamide}, volume={73}, ISSN={["1435-0661"]}, DOI={10.2136/sssaj2007.0426}, abstractNote={Depositional seals, formed when turbid waters infiltrate into soils, lead to a reduction in the hydraulic conductivity (HC) of soils and increased runoff. In this study, the effect of anionic polyacrylamide (PAM) on the HC and flocculation of depositional seals made of three clay minerals (montmorillonite, illite, and kaolinite), saturated with either Na or Ca, was investigated. A silt loam soil was packed in columns and leached with 5 g L−1 suspensions of the reference clays. Deposition of the clay particles on the soil surface formed seals. In the PAM treatment, dry granules of linear PAM were spread on the soil surface before the suspension application. Calcium seals were more permeable than Na seals in all the clay types, up to 26 times greater for montmorillonite. The HC of the seals for the clay minerals was in the order kaolinite (2.8–3.5 mm h−1) > illite (0.6–3.0 mm h−1) > montmorillonite (0.09–1.0 mm h−1). The addition of PAM generally enhanced clay flocculation, with the magnitude of the enhancement depending on the type of the exchangeable cation. The Na‐saturated seals in the three clay types had significantly higher initial HC with the PAM treatment. This increase, however, was transient except in Na‐illite. The impact of PAM on the degree of clay flocculation and floc density partially explained the effects of PAM on the HC of the depositional seals. An increase in clay flocculation or a decrease in floc density caused by PAM resulted in an increase in depositional seal HC.}, number={3}, journal={SOIL SCIENCE SOCIETY OF AMERICA JOURNAL}, author={Bhardwaj, A. K. and McLaughlin, R. A. and Shainberg, I. and Levy, G. J.}, year={2009}, pages={910–918} }
 @article{mandal_bhardwaj_warrington_goldstein_bar tal_levy_2008, title={Changes in soil hydraulic conductivity, runoff, and soil loss due to irrigation with different types of saline-sodic water}, volume={144}, ISSN={["0016-7061"]}, DOI={10.1016/j.geoderma.2008.01.005}, abstractNote={Irrigation with saline–sodic water causes sodic conditions in the soil which reduces soil productivity. We evaluated the changes in a number of important indices related to soil structural stability when treated wastewater (TWW), albeit with higher loads of organic matter and suspended solids, was used instead of more saline–sodic irrigation water, under different degrees of aggregate slaking. We studied soil saturated hydraulic conductivity (HC) using disturbed samples packed in columns, and soil infiltration rate, runoff and erosion under simulated rainfall. Aggregate slaking was manipulated by wetting the samples prior to all tests at either a slow (1–2 mm h− 1) or a fast (50 mm h− 1) rate. Samples of a calcareous silty clay (Typic Calciorthids) from the Bet She'an Valley, Israel, were taken from plots irrigated for three years with either TWW, saline–sodic Jordan River water (JRW), or moderately saline–sodic spring water (SPW), and also from a non-cultivated area (control). With little or no aggregate slaking (use of slow wetting), higher HC values and lower amounts of total runoff and soil loss were measured compared to when more severe aggregate slaking was induced (use of fast wetting). The HC values for the TWW treatment were similar to, or lower than, those for the control and significantly higher than those for the JRW treatment. For the runoff and soil loss data, differences among the water quality treatments were, generally, more pronounced when aggregate slaking was substantially reduced, and were related to soil sodicity. Under the latter condition, runoff and soil loss from the TWW treatment were comparable with those from the control and significantly lower than those from the JRW treatment. Our results suggested that replacing saline–sodic irrigation water with TWW could have favorable effects on soil structural stability, especially under conditions where aggregate slaking can be reduced (e.g., in regions with low to moderate rain intensities; and/or use of low intensity irrigation systems).}, number={3-4}, journal={GEODERMA}, author={Mandal, Uttam Kumar and Bhardwaj, A. K. and Warrington, D. N. and Goldstein, Dina and Bar Tal, A. and Levy, G. J.}, year={2008}, month={Apr}, pages={509–516} }
 @article{bhardwaj_mclaughlin_babcock_2008, title={Energy dissipation and chemical treatment to improve stilling basin performance}, volume={51}, DOI={10.13031/2013.25321}, abstractNote={Surface water pumped from construction sites frequently contains high levels of turbidity and suspended sediment, which are not effectively removed using gravity-based systems. This study assessed the effects of modifying a permanent pool stilling basin with energy dissipaters and with the addition of polyacrylamide (PAM) on turbidity and suspended sediments. Turbidity was generated by injecting soil into flowing water at a fixed rate for 30 min in a source basin. Turbid water from this basin was pumped from the surface to the stilling basin with physical and chemical treatments. Three energy dissipater treatments were tested: bottom inlet level spreader (BILS; silt fence fabric installed with 40 mm opening from the basin bottom), coir baffles (900 g m-2 coir fabric with 0.45 open space fraction (OSF), and Pyramat baffles (synthetic fabric with 0.10 OSF). The tests were run either with or without PAM dosing by passing the flow over a solid PAM block at the stilling basin inlet. The physical treatments (i.e., energy dissipation) did not significantly affect the turbidity and total suspended solids (TSS) of the water exiting the basin, which were reduced by up to 29% and 36%, respectively. The chemical treatment was much more effective regardless of the physical treatment, either in combination or alone, reducing turbidity and TSS up to 88% and 84%, respectively. The baffle materials collected much more suspended sediment when PAM was added, with twice as much sticking to the coir than the Pyramat, although overall the latter may be more effective in settling the flocs. The patterns of turbidity and TSS within the basin suggest that only one porous baffle is adequate for PAM-treated water, and that the reduction observed near the outlet was likely floc interception by the sloped wall of the basin outlet. This study provides a relatively simple, inexpensive approach to improving the function of stilling basins for treating turbid water.}, number={5}, journal={Transactions of the ASABE}, author={Bhardwaj, A. K. and McLaughlin, R. A. and Babcock, D. L.}, year={2008}, pages={1645–1652} }
 @article{bhardwaj_mclaughlin_2008, title={Simple polyacrylamide dosing systems for turbidity reduction in stilling basins}, volume={51}, DOI={10.13031/2013.25324}, abstractNote={Stilling basins are often ineffective in reducing turbidity and total suspended solids (TSS) in water containing fine sediments. This study determined the effectiveness of two polyacrylamide (PAM) dosing systems to flocculate suspended materials and the influence that porous baffles have on the two systems. Turbid water was generated by injecting soil into pond water flowing into a mixing basin for 30 min. Turbid water containing mostly fine suspended sediments was pumped from the surface of the mixing basin to a test stilling basin with physical and chemical treatments. The physical treatments were either an open basin or one with three porous baffles of 900 g m-3 coir matting. The chemical treatment was either passive using a PAM block or active using a PAM solution injected into the water pump intake at 4 mg L-1 in the pumped water. The passive treatment involved pumping turbid water over the PAM block at the basin entrance, dissolving the PAM as the water flowed over the block. Sampling for turbidity and total suspended solids (TSS) was done at 5 min intervals at the inlet, outlet weir, and four surface and bottom points inside the basin. In laboratory screening for PAM formulation and dose, tests conducted with whole soil resulted in greatly reduced turbidity, while those with only the suspended fraction had a much lower turbidity reduction. In the stilling basin, detention times of 1.5 or 24 h both had no effect on turbidity or TSS at the outlet. The turbidity of untreated discharges ranged from 220 to 260 nephelometric turbidity units (NTU), while both active and passive dosing significantly decreased the turbidity by 66% to 88%. Porous baffles had little effect compared to the PAM treatment. The active PAM treatment significantly reduced TSS at the outlet by up to 80%, but the 45% to 65% reduction by the passive system was not significantly different from the untreated tests. Patterns within the basins indicated that suspended flocs in PAM-treated water may have been intercepted and removed by the sloped dam wall, a phenomenon not observed in the untreated water.}, number={5}, journal={Transactions of the ASABE}, author={Bhardwaj, A. K. and McLaughlin, R. A.}, year={2008}, pages={1653–1662} }