Effect of high concentration

Another subsidiary field of study was the effect of high concentrations of a diffusing solute, such as interstitial carbon in iron, in slowing diffusivity (in the case of carbon in fee austenite) because of mutual repulsion of neighbouring dissolved carbon atoms. By extension, high carbon concentrations can affect the mobility of substitutional solutes (Babu and Bhadeshia 1995). These last two phenomena, quenched-in vacancies and concentration effects, show how a parepisteme can carry smaller parepistemes on its back. 

At low ionic strengths, Tm increases exponentially with ion activity. The effect of high concentrations of salts or miscible solvents depends on the influence they have on hydrogen-bonding and may increase or decrease Tm. In the case of xanthan gum, the value of Tm can be adjusted from ambient to over 200°C by the addition of appropriate salts. Table 7.2 presents Tm values for some industrial viscosifiers. 

Effect of High Concentration of Substrate on Immobilised cells... 

The measurement of pH is further complicated by the effect of high concentrations of sucrose (such as 60 Brix or 60%w/w) on hydrogen ion activity. 

Sivalingam, P.M. 1978. Effects of high concentration stress of trace metals on their biodeposition modes in Ulva reticulata Forskal. Japan. Jour. Phycol. 26 157-160. 

Cresols are released to soil at landfills and hazardous waste sites. In general, cresols will degrade in soil very rapidly. However, cresols may persist in soil under anaerobic conditions or due to the toxic effects of high concentrations of cresols or other associated compounds. Tables 5-2a through 5- 2e include monitoring data for these sources. The land application of municipal sewage sludges that contain cresols may also release cresols to soil (Demirjian et al. 1984, 1987). 

Oberst, F.W., Crook, J.W., Swaim, S.F., Ward, F.P.E., Koon, W.S., Musselman, N.P., Swan, D.J., and Smith, H.A. Toxic effects of high concentrations of bromobenzylnitrlle (CA) vapor in various animal species. U.S. Army Medical Research Laboratory, Edgewood Arsenal, Md. EATR 4078. 1967. 32 p. 

Effects of high concentrations of benzaldehyde 4 on the enantioselectivity of the carboligation reaction have been described previously [4, 5]. Siegert et al. described the increase of R)-7 for a BED variant by increasing the concentration of benzaldehyde 4 from 1 to 10 mM, and Iding et al. were able to increase the enantioselectivity of wild-type BFD by keeping the concentration of benzaldehyde 4 at a low level. Surprisingly, acetaldehyde 6 showed no such effect. More recently, we... 

L-arginine protects against inactivating effects of high concentrations of urea [3]... 

It should not be assumed that anomalous concentrations necessarily indicate contamination. Bolviken and Lag (1977) have described areas in Norway where the absence of vegetation is due to the toxic effects of high concentrations of metals in soils as a result of weathering of sulphide ores close to the surface. This is a natural process having nothing to do with contamination. 

If the toxic effect of a chemical combination is tested and compared with the effect of the individual chemicals, it may happen that the effect of the tested mixture deviates from the effect predicted by CA or IA. This mixture can be considered as 1 combination of the endless number of other possible combinations in which these chemicals can be mixed. If more combinations of this specific set of chemicals are tested, it can happen that effects of a number of different combinations at low concentrations differ from CA or IA, but that the effects of high-concentration combinations are well predicted. Such a systematic deviation pattern may be relevant for risk assessment, or may provide insight into the modes of action. Three types of systematic deviations from CA or IA can be defined as biologically relevant, based on studies published in the literature ... 

Figure 4. Effect of high concentrations of ethanol on the phase behavior of 5 wt% EMAA3.1 in butane [6],...

Inhibitory effects of high concentrations of LDL (2000 pg/ml) on endothelium-dependent arterial relaxation have been reported by Andrews et al. [119]. These authors suggested that the effects are mediated by an apolipoprotein receptor mechanism involving native LDL. 

Another popular view is the so-called "salt-buffer hypothesis" which gives attention to the effects of highly concentrated salt solution in the unfrozen phase on frozen muscle proteins. 

Apart from the acute toxic effects of high concentrations of the more volatile solvents, there are health hazards from the long-term (chronic) exposure to low levels of solvents. Reproductive effects that are associated with chronic exposure to some solvents used in laboratories are shown in Table 11.8. Evidence from animal studies suggests there are reproductive hazards from handling other solvents. Eor example ... 

Acclimation to the toxic effect of high concentrations of the light metal cations was significant. Figure 14 illustrates the extent of the acclimation observed. 

The effect of potassium on the kinetic constants is illustrated in Figure 15. Only the maximum specific growth rate, km, and the maximum specific substrate utilization rate, k, were affected by increases in potassium. These data were used to plot Figure 16, which indicates that the toxic effect of high concentrations of potassium is caused by a reduction in the rate at which each methane organism can process acetate. 

Urase, X. et al.. Effect of high concentration of organic and inorganic matter in landfill leachate on the treatment of heavy metals in very low concentration level. Water Sci. Technol, 36(12, Water Quality Conservation in Asia), 349, 1997. 

DePaola, P.F. Soparkar, P. Foley, S. Bookstein, F. Bakhos, Y. Effect of high-concentration ammonium and sochum fluoride rinses on dental caries in school children. Commun. Dent. Oral Epidemiol. 1977, 5 (1), 7-14. 

In a randomized study of the respiratory effects of high concentrations of halothane and sevoflurane in 21 healthy boys undergoing inguinal or penile surgery, there was similar respiratory depression with each agent (13). Minute ventilation fell by about 50% as a result of a reduction in tidal volume, despite an increase in respiratory rate. 

Sutton DD, Arnow PM, Lampen JO. Effect of high concentrations of nystatin upon glycolysis and cellular permeability in yeast. 

A. Effects of High Concentration and Orientation on Reaction Rate. . . 312... 

Steen, R.W.J. and Porter, M.G. 2003. The effects of high-concentrate diets and pasture on the concentration of conjugated linoleic acid in beef muscle and subcutaneous fat. Grass Forage Sci 58, 50-57. 

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