Theory of buffer action

2004 ◽  
pp. 18-34
Author(s):  
R. J. Beynon ◽  
J. S. Easterby
Keyword(s):  
1924 ◽  
Vol 1 (3) ◽  
pp. 169-191
Author(s):  
H. Katagiri
Keyword(s):  

1925 ◽  
Vol 15 (2) ◽  
pp. 201-221 ◽  
Author(s):  
Edward M. Crowther

A hydrogen electrode apparatus for soils is described. Similar or adjacent soils may show considerable differences inpH value, with no changes in their degrees of buffer action, as shown in titration curves with lime water. In such cases the conventional “lime requirements” are correlated with thepH values, but no such relation holds in dissimilar soils. ThepH value of a soil suspension is intimately connected with the nature and amount of the cations present. Neutral salts markedly increase the hydrogen ion concentration of both acid and slightly alkaline soils. Sodium salts, including the hydroxide, give lower hydrogenion concentrations than the corresponding potassium or calcium salts, and chlorides give lowerpH values than sulphates. The degree of buffer action (slope of titration curve) is unaffected by the addition of a neutral salt. Previous extraction of a soil with water causes a considerable increase i n thepH value of its suspensions. A number of soils showed a regular increase of about 0·1 inpH. value for twofold dilution. The “salt effect” and “dilution” effect appear to be of the same type. It is recommended that the soil-water ratio of 1:5 be generally adopted. The indicator methyl red gives erroneouspH values in turbid soil suspensions owing to the absorption of the red form, which is apparently a cation capable of undergoing “base exchange” with the soil.


1991 ◽  
Vol 22 (4) ◽  
pp. 447-451
Author(s):  
Atsushi YAMAGUCHI ◽  
Toshiharu KAZAMA
Keyword(s):  

1980 ◽  
Vol 35 (6) ◽  
pp. 736-740 ◽  
Author(s):  
Norio Miyoshi ◽  
Giiti Tomita

Abstract The optical properties (absorption and fluorescence) of fluorescein sodium were investi-gated with changing the bulk pH value in aqueous, water-methanol mixed and dodecyl-ammonium propionate reversed micellar solutions. A strong buffer action was found in the reversed micellar solutions. The pKa values for the equilibrium between fluorescein mono-and di-anions in the ground and excited singlet states highly decreased in the reversed micellar solutions compared with those in non-micellar solutions. The micellar buffer action strongly affected the initial rate of the 1,3-diphenylisobenzofuran oxidation caused by the photosensitization of fluorescein. The buffer action was closely related to the solubilized water content.


1984 ◽  
Vol 18 (1) ◽  
pp. 67-70
Author(s):  
M. Okazaki ◽  
D.O. deShazer ◽  
L. Singer

2019 ◽  
Vol 85 (9) ◽  
pp. 3-16
Author(s):  
Ruslan Khoma ◽  
Alim Ennan ◽  
Aleksandr Chebotarev ◽  
Sergey Vodzinskii

The investigations of acid-base interactions in aminomethanesulfonic acid (AMSA)–potassium aminomethanesulfonate–water and alkylaminomethanesulfonic acid–potassium alkylaminomethane-sulfonate–water systems, where alkyl are methyl (MeAMSA), N-(2-hydroxyethyl) (HEAMSA), n-propyl (n-PrAMSA), n-butyl (n-BuAMSA), tert-butyl (t-BuAMSA), n-heptyl (n-HpAMSA) and benzyl (BzAMSA) were performed in temperature range 293–313 К. Buffer action pH limits were determined and the buffer capacity of these systems was estimated.Based on the evaluation of buffer action pH limits of aminomethansulfonic acids, it has been found that with the help of n-PrAMSA and n-BuAMSA, it was possible to maintain the medium acidity in the range of physiological pH values throughout the range of investigated temperatures.As the temperature rises, the pH of the lower buffer limit increases for AMSA and n-BuAMSA systems, while for HEAMSA, t-BuAMSA, n-HpA-MSA and BzAMSA decreases. The value of the pH of the upper buffer threshold for all tested systems decreases during their heating. With the increase of the electron-donor properties of the N-substituent in the AMSA–MeAMSA–HEAMSA–t-BuAMSA series, the value of their electronegativity decreases to result in lowering of the pH values of the lower buf-fering action limit of these systems. For the more lipophilic N-substituents (n-C4H9, n-C7H15 and C6H5CH2), this regularity is not typical.It has been established that with increasing the CYAMSK/CYAMSA concentration ratio, the buffer capacity of YNHCH2SO3H–YNHCH2SO3K–H2O systems with hydrophilic aminomethansulfonic acids (Y = H, CH3 and HOCH2CH2) increases. For systems with lipophilic n-PrAMSA and t-BuAMSA, their buffer capacity doesn’t change at 0.4 ≤ QKOH/QYAMSA ≤ 1.0.The obtained data on the buffer capacity of the investigated systems is recommended for use in chemical analysis, microbiological and biochemical studies.


1931 ◽  
Vol 23 (8) ◽  
pp. 587-605 ◽  
Author(s):  
L. D. Baver
Keyword(s):  

2007 ◽  
Vol 33 (3) ◽  
pp. 273-277 ◽  
Author(s):  
Junji Shibata ◽  
Norihiro Murayama ◽  
Shinsuke Nakajima

Author(s):  
D. D. Perrin ◽  
Boyd Dempsey
Keyword(s):  

1921 ◽  
Vol 13 (10) ◽  
pp. 916-918
Author(s):  
C. H. Bailey ◽  
Anna C. Peterson

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