Effect of Calcium Concentration

Ca After After After Water DOC UV254niti Cal.cium 

Concentration Recycle 3 Experiment Rinse Loss Loss Loss 

Ca Concentration [mlv f After Recycle 3 J/Jiv., After Experiment After Water Rinse DOC Loss [%] ([mg]) U V 254nm Loss [%] ([cm-i]) Calcium Loss [%] (M) 

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Sayer, M.D.J., J.P. Reader, and R. Morris. 1989. The effect of calcium concentration on the toxicity of copper, lead and zinc to yolk-sac fry of the brown trout, Salmo trutta L., in soft, acid water. Jour. Fish Biol. 35 323-332. 

Muller-Buschbaum, P., Gebhardt, R., Roth, S.V., Metwalli, E., Doster, W. (2007). Effect of calcium concentration on the structure of casein micelles in thin films. Biophysical Journal, 93, 960-968. 

Figure 6.9 Effect of calcium concentration on DOC rejection (15 mgL DOC NOM concentrate, 20 mM NaCl, 1 mM NaHCO, 0.5 mM CaCl, pH 8).

Figure 7.21 Effect of calcium concentration on flux decline of TFC-S membrane, pH 8, 1 mM NaHCO. conductivity 2 mScm adjusted with NaCl.

Figure 7.23 Effect of calcium concentration on final flux of the TFC-S and TFC-SR membranes.

Figure 5.1 Effect of oxygen concentration on corrosion of mild steel in slowly moving water containing 165 ppm CaCl2 48-hour test, 25°C. [Courtesy of H. H. Uhlig, D. N. Triadis, and M. Stern, Effect of Oxygen, Chlorides, and Calcium Ion on Corrosion Inhibition of Iron by Polyphosphates, J. Electrochem. Soc. 102, p. 60 (1955). Reprinted with permission by The Electrochemical Society, Inc. ]...

Dietary calcium intake appears to affect lead absorption. An inverse relationship has been observed between dietary calcium intake and blood lead concentration in children, suggesting that children who are calcium deficient may absorb more lead than calcium replete children (Mahaffey et al. 1986 Ziegler et al. 1978). An effect of calcium on lead absorption is also evident in adults. In experimental studies of adults, absorption of a single dose of lead (100-300 ig lead chloride) was lower when the lead was... 

In a review of the course and mechanism of the catalytic decomposition of ammonium perchlorate, the considerable effects of metal oxides in reducing the explosion temperature of the salt are described [1], Solymosi s previous work had shown reductions from 440° to about 270° by dichromium trioxide, to 260° by 10 mol% of cadmium oxide and to 200°C by 0.2% of zinc oxide. The effect of various concentrations of copper chromite , copper oxide, iron oxide and potassium permanganate on the catalysed combustion of the propellant salt was studied [2], Similar studies on the effects of compounds of 11 metals and potassium dichromate in particular, have been reported [3], Presence of calcium carbonate or calcium oxide has a stabilising effect on the salt, either alone or in admixture with polystyrene [4],... 

Of the elements characteristically present as major components of nonsaline waters, only calcium produced a slight interference. A weak calcium line at approximately 190.73 nm partially overlaps the sulfur fine such that 1000 mg/1 Ca produces an apparent signal of 25 mg/1 sulfate. Correction for this interference is easily achieved by establishing the relationship between calcium concentration and apparent sulfate signal, and inserting this information in the controlling software. The effect of calcium was then automatically subtracted during the measurement of the sample. 

Spencer and Sachs [29] determined particulate aluminium in seawater by atomic absorption spectrometry. The suspended matter was collected from seawater (at least 2 litres) on a 0.45 tm membrane filter, the filter was ashed, and the residue was heated to fumes with 2 ml concentrated hydrofluoric acid and one drop of concentrated sulfuric acid. This residue was dissolved in 2 ml 2 M hydrochloric acid and the solution was diluted to give an aluminium concentration in the range 5-50 pg/1. Atomic absorption determination was carried out with a nitrous oxide acetylene flame. The effects of calcium, iron, sodium, and sulfate alone and in combination on the aluminium absorption were studied. 

The effect of calcium interference is somewhat different. At its concentration in seawater, 0.010 M, calcium ion had no effect upon chemiluminescence analysis of a 6 x 10 8 M Crm solution in the absence of bromide ion. The... 

Acute oral doses (500 mg/kg) given to healthy sheep caused tremors of the facial muscles (Fowler 1969b) several liver-fluke-infected sheep experienced prostration with even lower doses (170 or 338 mg/kg) (Southcott 1951). Treatment of sheep with calcium relieved the clinical signs of neurotoxicity, suggesting that cellular availability of calcium ion may be related to the neuromuscular symptoms noted (Southcott 1951). Therefore, mechanistic studies of neuromuscular impulse transmission and cognitive function in animals would be useful. These neurological studies should examine the effects of different concentrations of hexachloroethane in several species. 

Corneau, L., Lavigne, C., and Zee, J. A. (1996). Effect of calcium and zinc concentrations and calcium source on in vitro calcium and zinc solubility in a fiber-fortified enteral formula. Nutr. Res. 16,1659-1669. 

These drugs act by binding to Pj-adrenoceptors on myometrial cell membranes and activating adenylyl cyclase. This in turn increases levels of cAMP in the cell (Fig. 62.1), activating cAMP-dependent protein kinase, hence decreasing intracellular calcium concentrations and reducing the effect of calcium on muscle contraction. 

Lugli, J. Gaziola, S.A. Azevedo, R.A. Effects of calcium, S-adenosylmethio-nine, S-(2-aminoethyl)-L-cysteine, methionine, valine and salt concentration on rice aspartate kinase isoenzymes. Plant Sci., 150, 51-58 (2000)... 

The effect of calcium acetate in the reaction medium at higher concentrations of 4 was rather surprising as the enzymatic reaction proceeded without any problem at substrate loads as high as 3M (765 gL" ) with conversion values ranging from 42 to 48% after 24h (see Table 8.2, entries 1-4). Since the level of calcium acetate used in these experiments did not exceed 170 mM, which is well below a stoichiometric ratio between the carboxylate of 13 and Ca , a more complex mechanism that probably involves enzyme stabilization as well as com-plexation of product might be taking place. 

Fig. 10. The effect of different concentrations of the ionophore X 537 A on calcium release, by sarcoplasmic reticulum vesicles11S. The reaction mixture contained 20 mM Tris-maleate pH 6-8, 50 mM KC1, 10 mM MgClj, 0.1 mM CaCl2, 0.1 mM murexide and 0.27 mg protein/ml. Calcium uptake and release were followed by monitoring the changes in the absorbance undergone by murexide. The measurements were performed with a filter dual wave length (540—507 nm) double beam spectrophotometer...

Figure 8. Effect of varying concentrations of ATP on adsorption of calcium to stearic acid monolayer. (O), no ATP (, ), I0"5M ATP (A), 10 4M ATP, (A), 10 3M ATP ordinate, surface concentration of Ca2+ in moles/sq. cm. abscissa, —log molar concentration of Ca2+ at pH 7.6...

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