Development and demonstration of a free surface flow-dependent sampling technology

Statistical assessment of water quality data, obtained at the South Florida Water Management District (West Palm Beach, Florida) S-65E structure, illustrated significant differences and inconsistency in nutrient concentrations (Daas and Ebadian, 2003). The evaluation showed that currently used water sampling techniques are inadequate because of deficiencies in functionality and sensitivity to flow conditions at the structure. Moreover, the study indicated the need for a more precise sampling technology, which would consider variations in the velocity profile across the water column during the sampling process. Therefore, a new prototype sampling technology was designed and tested in a pilot open channel. The new sampler had the capability to collect discrete aliquot volumes of water samples that are proportional to the corresponding point velocity at each of these depths. The discrete aliquot volumes were blended to provide an integrated sample that captures the variations in the velocity profile.     

Inhibition of nitrification in soil by metal diethyldithiocarbamates

IntroductionNitrificationisaprocessinwhichammoniumformofnitrogenisconvertedintonitrateform .Nitrogenuseefficiencyintermsofplantuptakeisgenerallylowandvariesgreatlyunderdifferentsoilandcroppingconditions.MostfertilizerNappliedtosoilsisintheformofammonium orammoniumproducingcompoundssuchasurea,andisusuallyoxidizedrapidlytonitratebynitrifyingmicroorganismsinsoils.Applicationofnitrogenfertilizersmorethanoptimumlevelsleadstolownitrogenrecoveriesandgreaternitrogenaccumulationinthesoilprofile .Theac…     

Factors affecting alkaline nature of rain water in Agra (India)

Rain water was collected and analysed from a reference site, Dayalbagh and Taj Ganj, near the Taj Mahal in Agra. The ionic components Ca, Mg, Na, K, NH(4), Pb, Fe, Zn, SO(4), HCO(3), Cl and F were analysed along with pH, alkalinity and conductance. The average pH of rain water at both sites is 7.05. There is a dominance of alkaline components, particularly Ca. The rain water chemistry shows the importance of calcareous soil-derived materials in controlling the pH of rain water.     

Edaphological characteristics of unweathered and weathered fly ashes from Gondwana and lignite coal

Naturally weathered and unweathered samples of fly ashes produced from Gondwana and lignite coals were characterized for their edaphological properties. The particle size distribution in these fly ashes varied widely, and the percentage of [Formula: see text] size particles governed their water holding capacity. All fly ashes were noncoherent in the dry state and had lower particle density than quartz and mulite. The fly ashes were low in available N, but were sufficient in available P, K, Ca, Mg, S, Cu, Fe, Mn, Zn and B. Among the fly ashes, unweathered lignite fly ash was the richest source of K, Ca, Mg, S and Fe, while weathered lignite fly ash had the highest amounts of Mn, Zn and B. The pH of the fly ashes was closely related to the ratio of exchangeable Ca to exchangeable Al. The fly ashes were high in soluble salt, but were poor in cation exchange capacity. As an amendment to correct soil pH, the fly ashes had a poor buffering capacity. Weathering decreased the total Fe, available S and exchangeable Na percentages, but increased the organic C content of the fly ashes. Invariably, an excess of soluble salts and exchangeable Na could limit plant growth on fly ash dumps. Toxic levels of B and Al existed in only some fly ashes.     

Distribution of radiotin (Sn) in partially hepatectomised rats and its binding with subcellular components of liver cells

Distribution of radiotin (Sn¹¹³) in target organs and in the hepatic subcellular fractions was studied in sham and partially hepatectomised rats 72 hrs after the administration of tin (II) tartrate (2 mg Sn⁺⁺, 10 uCi/100 gm body weight) intraperitoneally. The results indicate that in both the groups Sn¹¹³ was maximally accumulated in liver followed by kidney and spleen. Partially hepatectomised rat however accumulated less Sn¹¹³ in liver while an increase was observed in kidney. Subcellular studies showed significantly high affinity of tin for microsomes. A compartmental shift of radiotin from cytosol to microsomal fraction was observed in hepatectomised rats when compared to sham operated rats.