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Not AvailableTea (Camellia sinensis L.) is a perennial acidophilic crop, and known to be a nonalcoholic stimulating beverage that is most widely consumed after water. The aim of this review paper is to provide a detailed documentation of selected micronutrient contents, viz. boron (B), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), and zinc (Zn) in made tea and tea infusion. Available data from the literature were used to calculate human health aspect associated with the consumption of tea infusion. A wide range of micronutrients reported in both made tea and tea infusion could be the major sources of micronutrients for human. The content of B, Co, Cu, Fe, Mn, Mo, and Zn in made tea are ranged from 3.04 to 58.44 μg g−1, below detectable limit (BDL) to 122.4 μg g−1, BDL to 602 μg g−1, 0.275 to 13,040 μg g−1, 0.004 to 15,866 μg g−1, 0.04 to 570.80 μg g−1 and 0.01 to 1120 μg g−1, respectively. Only 3.2 μg L−1 to 7.25 mg L−1, 0.01 μg L−1 to 7 mg L−1, 3.80 μg L−1 to 6.13 mg L−1, 135.59 μg L−1 −11.05 mg L−1, 0.05 μg L−1 to 1980.34 mg L−1, 0.012 to 3.78 μg L−1, and 1.12 μg L−1 to 2.32 μg L−1 of B, Co, Cu, Fe, Mn, Mo, and Zn, respectively, are found in tea infusion which are lower than the prescribed limit of micronutrients in drinking water by World Health Organization. Furthermore, micronutrient contents in tea infusion depend on infusion procedure as well as on the instrument used for analysis. The proportion of micronutrients found in different tea types are 1.0–88.9% for B, 10–60% for Co, 2.0–97.8% for Cu, 67.8–89.9% for Fe, 71.0–87.4% for Mn, 13.3–34% for Mo, and 34.9–83% for Zn. From the results, it can also be concluded that consumption of three cups of tea infusion per day does not have any adverse effect on human health with respect to the referred micronutrients rather got beneficial effects to human.Not Availabl

Comblike Polyacrylamides as Flooding Agent in Enhanced Oil Recovery

<p>The oil recovery from core material and a specifically designed flow cell using novel branched (comblike) polyacrylamides (PAM) has been investigated. The injectivity characteristics of the different branched PAMs were evaluated by filtration tests and core-flow experiments. The number of arms of the branched PAM has little to no effect on the filterability and permeation through a porous medium. The 13-arm branched PAM displayed a higher residual resistance factor (RRF) in Berea sandstone than its linear analogue and a commercial HPAM. In addition, the thickness of the layer adsorbed at the rock surface is higher for the branched PAM. Oil trapped in dead-end pores is simulated using a 2D flow cell and the effect of the number of arms on the recovery of residual oil is evaluated. In brine solutions, the branched PAMs perform equal or better than their linear analogues in terms of the solution viscosity. The oil recovery of a branched PAM with a similar molecular weight is 3 times as high as that for the commercial polymer. The recovery efficiency, evaluated using low permeable Berea as the porous medium, is significantly improved by using branched PAM instead of linear ones (5.0 compared to 1.5% of the OOIP). An improvement is also observed when high permeable Bentheim cores are used as the porous medium (9.4% compared to 6.0% of the OOIP). The higher oil recovery in the 2D flow cell might explain the improved performance of the branched PAMs. The high thickening capability and the low molecular weight of the branched PAMs makes them suitable for application in enhanced oil recovery (EOR, especially for low permeable reservoirs).</p>