Chemical quality of bottled waters from three cities in eastern Alabama

Twenty-five brands of bottled waters consisting of both purified and spring types collected randomly from three Alabama cities, USA were assessed for their suitability for human consumption. Water quality constituents analyzed include pH, conductivity, alkalinity, chloride, nitrate + nitrite, sulfate, phosphate, total carbon (TC), inorganic carbon (IC), total organic carbon (TOC), and 27 elements on the inductively coupled plasma-optical emission spectrometer (ICP-OES). The results obtained were compared with US EPA drinking water standards and the European union (EU) drinking water directive. Ni was non-detectable in all the samples and Cu, Pb, Sb, Zn, Mn, Al, Cr, Mg, P, Ca, sulfate, chloride and nitrates + nitrites were all below their respective USEPA drinking water standards or EU maximum admissible concentrations (MAC). The conductivity, pH, As, Cd, Hg, Zn, Se and Tl values in some samples exceeded the EU and USEPA standards for drinking water. No sample had pH > 8.5, but seven bottled water brands analyzed were acidic (pH < 6.5). Most of the sampled brands had TOC concentrations exceeding 3 mg/l. The concentrations of most water quality constituents analyzed, in most cases, were higher in the spring water brands compared to the purified or distilled brands of bottled water. A one-way parametric analysis of variance (ANOVA) conducted on pH, conductivity, IC, TOC, Ca, Na, K, Mg, Se, sulfate, chloride and nitrate + nitrite values for 10 brands of bottled water to ascertain the homogeneity of variances within and between the brands, suggested significant differences in variances across the brands at a 95% confidence level except for selenium, sodium and calcium.     

Trace element content of fish feed and bluegill sunfish (Lepomis macrochirus) from aquaculture and wild source in Missouri

Trace element content of fish feed and bluegill sunfish muscles (Lepomis macrochirus) from aquaculture and natural pond in Missouri were determined using the inductively coupled-plasma optical emission spectrometer (ICP-OES) and the direct mercury analyzer (DMA). Dietary intake rates of trace elements were estimated. Dogfish muscle (DORM-2) and lobster hepatopancreas (TORT-2) reference standards were used in trace element recovery and method validations. The average elemental concentrations (mg/kg diet, dry wt.) of fish feed were: As 1.81, Cd 2.37, Co 0.10, Cr 1.42, Cu 8.0, Fe 404, Mn 35.9, Ni 0.51, Pb 9.16, Se 1.71, Sn 20.7, V 0.09, Zn 118 and Hg 0.07. The mean elemental concentrations (μg/kg wet wt.) in bluegill muscles from both aquaculture and wild (in parenthesis) sources were: As 0.36 (0.06), Cd 0.28 (0.01), Co 0.0 (0.0), Cr 0.52 (0.05), Cu 0.38 (0.18), Fe 17.5 (2.43), Mn 0.18 (0.24), Ni 0.18 (0.04), Pb 1.03 (0.04), Se 0.34 (0.30), Sn 0.66 (0.42), V 0.02 (0.01), Zn 6.97 (9.13) and Hg 0.06 (0.24). Kruskal–Wallis chi square indicated significant differences in As, Cd, Co, Cr, Cu, Fe, Ni, Pb, Sn, V, Zn and Hg (P < 0.001), Se (P < 0.01) and Mn (P < 0.05) across the sampling locations. Dietary intake rates, estimated from weekly consumption of 228 g of aquaculture and wild bluegills, posed no health risks for approximately 85% of all samples.     

Particle coarsening behavior of α-β titanium alloys

A systematic study was undertaken to develop particle coarsening relationships in terms of time, temperature, and volume percents of phases and to determine the rate-controlling mechanisms for the coarsening of α-β Ti-Mn and Ti-V alloys. This investigation is confined to equiaxed-type α+ β microstructures. For a given alloy anc te nperature, the coarsening of particles refers to the growth of particles under essentially constant volume percents of the component phases. The coarsening exponents increased from 0 24 to 0.29 and from 0.28 to 0.32 for Ti-V and Ti-Mn systems, respectively, when the temperature was increased from 973 to 1073 K. In addition, it was found that the activation energy chances as the temperature is increased from 973 to 1108 K for the Ti-Mn system. Based on these results, it is suggested that the rate-controlling mechanism for particle coarsening changes from mixed (bulk + grain-boundary) diffusion control toward bulk diffusion control when the temperature is increased from 973 to 1108 K for the Ti-Mn system. Similarly, for the Ti-V system, it is suggested that the rate-controlling mechanism changes from grain-boundary diffusion control toward mixed diffusion control when the temperature is increased from 973 to 1073 K. These results clearly indicate that the rate-controlling mechanism depends on temperture as well as the diffusivities of the alloying elements. This paper is based on a presentation made in the symposium “Interfaces and Surfaces of Titanium Materials” presented at the 1988 TMS/AIME fall meeting in Chicago, IL, September 25–29, 1988, under the auspices of the TMS Titanium Committee.