Modified Larsons Ratio Incorporating Temperature, Water Age, and Electroneutrality Effects on Red Water Release

Corrosion indices have a historical as well as practical relevance in drinking water treatment. The development of reliable indicators of corrosion related problems, like red water, is an ongoing process in the drinking water industry. Due to the complexity of interaction among the physical, chemical, and biological reactions taking place within a typical distribution system, mechanistic models are difficult to formulate. Even if such a model was available, fitting it to actual field conditions would still be an empirical process. Corrosion indices give simplistic generalizations to complex corrosion phenomena. A modified form of the Larson Ratio that includes the effects of temperature and hydraulic retention time is proposed based on apparent color release data available from a 2 year pilot distribution system study.     

Effects of coal syngas impurities on anodes of solid oxide fuel cells

A literature review is conducted to summarize the studies on the identification of impurities in coal syngas and their effects on the performance of Ni-yttria stabilized zirconia (Ni-YSZ) anode of solid oxide fuel cells (SOFCs). Coal syngas typically contains major species, CO, H₂, CO₂, H₂O, CH₄, N₂, and H₂S as well as trace impurities. Thermodynamic equilibrium calculations have indicated that trace impurities species such as Be, Cr, K, Na, and V in the coal syngas form condensed phases under warm gas cleanup conditions and can be effectively removed by the cleanup processes. For meaningful data comparison, a practical parameter is formulated to quantify the level of degradation normalized with respect to the relevant experimental parameters. Experimental results show that the existence of Hg, Si, Zn and NH₃ in the coal syngas does not significantly affect the performance of the Ni-YSZ anode. The presence of Cd and Se in the syngas impacts the SOFC anode performance to some extent. Impurity species such as Cl, Sb, As, and P cause severe cell voltage degradation due to attack on the Ni-YSZ anode. Sb, As and P have the potential to react with Ni to form secondary phases in the Ni-YSZ anode, which deteriorate the catalytic activity of the anode.     

Sex differences in spatial ability and activity in two vole species (Microtus ochrogaster and M. pennsylvanicus).

The hypothesis that sex differences in maze learning result from sex differences in activity was tested with wild-caught prairie (Microtus ochrogaster) and meadow (M. pennsylvanicus) voles. For 38 voles error production and activity were simultaneously measured in a series of 7 symmetrical mazes. Repeated-measures analyses of variance (ANOVAs) examined species, sex, maze, and interaction effects for 3 dependent variables: errors, activity, and errors/activity. The pattern of significant effects was very different for the errors and activity ANOVAs, which suggests that differential activity cannot explain differential error rates. In contrast, the pattern of effects was very similar for errors and errors/activity ANOVAs, which suggests that controls for activity do not remove differences in error production. These results fail to support the activity hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship between embryonic and tumor lipids: I. Changes in the neutral lipids of the developing chick brain,heart and liver

Organ dry weight, per cent total lipid, per cent neutral lipid, per cent phospholipid, and neutral lipid class composition of embryonic and mature brain, heart and liver were determined at 10, 13, 16, 19, 22, 27 and 53 days after incubation was initiated. All three tissues showed an increase in total lipids from the 10th day to hatching (21st day). The 10th day brain showed relatively high levels of sterol esters which decreased with increased development while free sterol levels increased. Heart free sterol and sterol ester percentages decreased with increassed time, while triglyceride levels increased dramatically after the 16th day. Liver showed a massive accumulation of neutral lipid after the 17th day. The neutral lipid was not triglyceride, as might have been expected, but sterol ester. Liver sterol, sterol ester and triglyceride levels were approximately equal at the 10th and 13th days, after which time sterol ester rose rapidly to more than 90% of the total neutral lipids by the 19th day. The neutral lipid class distributions were characteristically different for each tissue throughout embryonic development. The relative high sterol ester levels in each of the tissues early in development suggests that the high level of sterol esters in neoplastic tissue may be related to the growth process of increasing cell numbers. On the other hand, the absence or the presence of only trace amounts of glyceryl ether diesters in any of the embryonic tissues suggests that the elevated levels of this lipid class in most tumors may be related to the neoplastic process or to conditions resulting from neoplasia.     

Effect of 2-hexadecynoic acid on cultured 7288C hepatoma cells

The effects of 2-hexadecynoic acid on the growth and lipid metabolism of cultured 7288 (HTC) cells have been evaluated. Growth was inhibited by the acetylenic acid: the LD₅₀ was 35–85 μM as determined by two methods at low and high cell densities. Reduced growth did not result from damaged plasma membranes as determined by α-amino isobutyrate leakage. DNA synthesis was unaffected by the acetylenic acid and the effect on RNA and protein synthesis appeared to be secondary to the effects on lipid metabolism. The 2-hexadecynoic acid inhibited lipid metabolism of the HTC cells at least at two levels. Data from both mass studies and radioactive acetate distributions in cellular and media lipids indicated that fatty acid elongation and acylation, especially triglyceride synthesis, were inhibited.     

Sulphur transformation and removal for Western Kentucky coals

Inhibition isotherms were measured for Western Kentucky No.9 coal. Crushed and sieved coal (?25 + 140 U.S. mesh) was fluidized in 10-g batches in a 22-mm i.d. quartz reactor up to a temperature of 870 °C. The release of hydrogen sulphide during heatup under nitrogen and at the run temperature (usually 1–2 h) under the same gas (pyrolysis), hydrogen, or hydrogen/hydrogen sulphide mixtures was followed by gas chromatography. The residue or char was analysed for pyritic, organic, sulphide, sulphate, and total sulphur. Inhibition isotherms, which are pseudo-equilibria between sulphur in the char and gaseous hydrogen sulphide, were measured at 600 and 870 °C. At the lower temperature the isotherm was found to be independent of the hydrogen sulphide concentration in the gas stream and the char sulphur content remained constant at 2.6%. At 870 °C the sulphur content of the char was greater than that of the original coal when gas mixtures of 1, 3, and 6% hydrogen sulphide in hydrogen were used, indicating the necessity of maintaining low hydrogen sulphide concentration for sulphur removal. In pure hydrogen, sulphur removal increased continuously from 47% at 600 °C to 84% at 870 °C. For pyrolysis under nitrogen, sulphur removal was 40% at 600 °C and increased to 59% at 740 °C. No further removal occurred above this temperature up to 870 °C. In addition to the inhibition isotherms, sulphur-form transformation diagrams were constructed for coal treated with nitrogen, hydrogen, and hydrogen/hydrogen sulphide mixtures. Pyritic sulphur, which comprised 40% of the sulphur in the original coal, was completely converted to ferrous sulphide at 600 °C in hydrogen and 740 °C in nitrogen. At 870 °C the sulphur content of the char produced under hydrogen was 1.1% made up of 48.4% ferrous sulphide, 43.4% organic sulphur, and 8.2% sulphate.