Buffering capacity total

Powell, G.E., Archer, D., 1989. On-line titration method for monitoring buffer capacity total volatile fatty acid levels in anaerobic digesters. Biotechnology and Bioengineering 33, 570-577. 

Holma, B. (1985). Influence of buffer capacity and pH-dependent rheological properties of respiratory mucus on health effects due to acidic pollution. Set. Total Environ. 41, 101-123. 

Fruit and vegetable juices packed with 21-26 in. of vacuum and stored in uncoated aluminum cans caused severe corrosion as shown in Table III. The corrosion rate brought about by the juices depends more on the nature of the organic acid present and the buffering capacity of the juice than on the total titratable acidity (11). The use of coated aluminum containers considerably minimized corrosion problems. Product control under extended storage conditions may be achieved by using specific chemical additives. However, more work is needed in this area before final conclusions can be reached. 

At equilibrium, the concentration of H+ will remain constant. When a strong acid (represented by H+ or HA) is introduced into solution, the concentration of H+ is increased. The buffer compensates by reacting with the excess H ions, moving the direction of the above reaction to the left. By combining with bicarbonate and carbonate ions to form the nonionic carbonic acid, equilibrium is reestablished at a pH nearly the same as that existing before. The buffer capacity in this case is determined by the total concentration of carbonate and bicarbonate ions. When no more carbonate or bicarbonate ions are available to combine with excess H+ ions, the buffer capacity has been exceeded and pH will change dramatically upon addition of further acid. 

Fixation in 6-12 hours with a mixture of sodium hydroxide and trisodium orthophosphate, a metering device being necessary. This method is recommended for regenerated cellulosic fibres. This formulation contains the same total amount of alkali as method (1) with the same bath stability, but may be preferred where some buffering capacity is required and sodium silicate is undesirable. 

The second dissociation step in phosphate (H2P04/HP04 ) also contributes to the buffering capacity of the blood plasma. Although the pKa value of this system is nearly optimal, its contribution remains small due to the low total concentration of phosphate in the blood (around 1 mM). 

In addition to changing the pH of the water, the uptake and release of CO2 alter the buffer capacity of the water. The effect upon buffer capacity is the result of two factors (1) the dependence of buffer capacity on the hydrogen ion concentration, and (2) the dependence of buffer capacity on the total concentration of weak acid and conjugate base in solution (67, 68). The precipitation of CaCO in natural waters reduces the buffer capacity to a value lower than that predicted on the basis of pH change and respiratory or photosynthetic changes in COL content of the water. 

In addition to the use of malo-lactic fermentation in red wines, it also has been tried in V. vinifera cultivar Chardonnay. In the experiments known to the author, the use of the malo-lactic fermentation in Chardonnay has not proved successful from a sensory point of view. In general, the rise in pH was too great and the buffering capacity of the wine too great to permit adequate adjustment with tartaric acid. However, this work is continuing in conjunction with a number of variations in the local viticultural practices to produce Chardonnay of a lower total acidity. In addition to the use of malo-lactic fermentation for the reduction of the acidity, considerable work has been done in Washington on the use of acid reduction with calcium. Both calcium carbonate and the double salt precipitation, as described by Steele (23, 24), have been utilized. Some very significant successes have been achieved, particularly with the double salt method. 

The variation of buffer capacity of the acetate buffer with respect to pH is shown in Figure 2.7 for the total concentration of 0.05 M. 

Whitfield, M. The ion-association model and the buffer capacity of the carbon dioxide system in sea water at 25 C and 1 atmosphere total pressure. Limnol. Oceanogr. 19,... 

The quantity a represent. the total concentration of free acid and salt, and so the buffer capacity is proportional to the total concentration of the solution. 

Plot the pH-buffer capacity curve for mixtures of acetic acid and sodium acetate of total concentration 0.2 n. Points should be obtained for mixtures containing 10, 20, 30, 40, 50, 60, 70, 80 and 90 per cent of sodium acetate, the pH s being estimated by the approximate form of the Henderson equation. Plot the buffer capacity curve for water at pH s 1, 2, 3 and 4, and superimpose the result on the curve for acetic acid. 

Utilize the general form of the acetic acid-acetate buffer capacity curve obtained in Problem 11 to draw an approximate curve for the buffer capacity over the range of pH from 2 to 13 of the universal buffer mixture described on page 415. It may be assumed that the total concentration of each acid and its salt is always 0.2 molar. 

Determination of total nitrogen content of the gastric juice, introduced by Wolff and Junghans (W22) and used later by others (D4), is inadequate for quantitation of gastric juice mucosubstances because proteins, peptides, and amino acids contribute to this measurement. Other authors precipitated gastric juice with methyl alcohol or acetone and determined the amount of alkali bound by the precipitate (M4-M6). These methods determined only the buffer capacity of the precipitate,... 

Various muscles differ sufficiently in their ability to neutralize protons (the muscles with different functional activities were compared including sprinters, as well as humans) and in all cases this ability correlates well with functional activity of a muscle. Especially high proton buffer capacity is in fast contracting muscles, which totally fit to anaerobic metabolism [25]. 

Alkalinity titrations of the 15 sequential batch stabilized/solidified waste extraets and of the acetic acid digestates were performed to determine the buffering capacity of the fixed waste and the rate of leaching of alkalinity from the waste. Fig. 1 shows the pH and alkalinity releases associated with one series of extractions. These analyses show a total buffering capacity of the stabilized waste ranging from 17.6 to 19.9 meg/g (dry weight) of fixed waste, with an average of 18.3 meq/g. 

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