Ionic strength effects on the activity coefficient of methylene blue and its self-association

1970 ◽  
Vol 92 (22) ◽  
pp. 6413-6415 ◽  
Author(s):  
Ashish Kumar Ghosh ◽  
Pasupati Mukerjee
Keyword(s):  
Methylene Blue ◽  
Ionic Strength ◽  
Activity Coefficient ◽  
Self Association

Speciation and Geochemical Implications of Carcass Burial Leachate

2018 ◽  
Vol 61 (2) ◽  
pp. 559-570
Author(s):  
Dyan L. Pratt ◽  
Terrance A. Fonstad
Keyword(s):  
Chemical Composition ◽  
Ionic Strength ◽  
Activity Coefficient ◽  
Swine Manure ◽  
Burial Site ◽  
Mass Mortality Event ◽  
Ammonium N ◽  
Ion Activity ◽  
Common Activity ◽  
The Impact

Abstract. In the event of a mass livestock mortality situation, disposal routes such as burial are commonly chosen. The impact of burial on the environment could be substantial, but the composition of the leachate arising from a burial site has not been well documented. This study was performed to determine the chemical composition of leachate arising from animal mortalities in a burial setting. Three species of livestock were used: bovine, swine, and poultry. Leachate collected from lined burial pits over two years of decomposition was analyzed for major and minor ions. Analysis indicated that livestock mortality leachate contains, on average, concentrations of 46,000 mg L-1 of alkalinity (as bicarbonate), 12,600 mg L-1 of ammonium-N, 2600 mg L-1 of chloride, 3600 mg L-1 of sulfate, 2300 mg L-1 of potassium, 1800 mg L-1 of sodium, and 1500 mg L-1 of phosphorus, along with lesser amounts of iron, calcium, and magnesium. Select samples had maximum concentrations of ammonium-N and bicarbonate up to 50% higher than these average values. In comparison to earthen swine manure storages and landfills, the ionic strength of the leachate was 2 to 4 times higher, and therefore its impact on water resources could be greater. Following the study of the chemical composition of livestock mortality leachate, the potential impacts of this leachate on the soil/water systems below a burial site were investigated. The ionic strength of the leachate presents its own set of challenges. Basic modeling of ion activity using the five most common activity coefficient equations (Debye-Hückel, extended Debye-Hückel, Truesdell-Jones, Davies, and Pitzer) were considered to assess the sensitivity of these methods for calculated ion activity as impacted by the ionic strength of the leachate. This was completed to further enhance the modeling and speciation efforts. Based on the results and the applicability of the Truesdell-Jones equation, PHREEQC was used to assess the chemical speciation of the leachate. The speciation of this leachate provides evidence of phosphate and sulfate compounds available for potential unattenuated transport. Understanding the geochemical implications of livestock mortality burial will give scientists and regulators more information for performing future risk analyses when considering mortality burial as a management option, either routinely or during a mass mortality event. Keywords: Ion activity coefficient, Ionic strength, Leachate chemical composition, Livestock burial leachate, Speciation.

Kinetics Studies of Methylene Blue Adsorption onto Spherical Chitosan Resin

2011 ◽  
Vol 233-235 ◽  
pp. 567-570
Author(s):  
Juan Qin Xue ◽  
Wei Bo Mao ◽  
Dan Dan Wen ◽  
Jing Xian Li ◽  
Yu Jie Wang
Keyword(s):  
Methylene Blue ◽  
Kinetic Equation ◽  
Ionic Strength ◽  
Adsorption Process ◽  
Sorption Kinetics ◽  
Methylene Blue Adsorption ◽  
Initial Concentration ◽  
Kinetics Studies ◽  
Kinetics Of ◽  
Chitosan Resin

Investigated the sorption kinetics of methylene blue on spherical chitosan resin. Studied the influences of ionic strength, pH， initial concentration on the adsorption process. The adsorption of methylene blue increases with the decreasing ionic strength and the increasing pH and the initial concentration of the system. Furthermore, the adsorption process correspondes with Lagergren pseudo-second kinetic equation and the finess (R2) of the model was above 0.99.

Which value for the first dissociation constant of carbonic acid should be used in biological work?

1991 ◽  
Vol 260 (5) ◽  
pp. C1113-C1116 ◽  
Author(s):  
R. W. Putnam ◽  
A. Roos
Keyword(s):  
Ionic Strength ◽  
Activity Coefficient ◽  
Dissociation Constant ◽  
Carbonic Acid ◽  
Mass Action ◽  
Bicarbonate Concentration ◽  
Apparent Dissociation Constant ◽  
Logarithmic Form ◽  
Ion Activity ◽  
Hasselbalch Equation

The apparent first dissociation constant of carbonic acid has been defined in different ways in the literature. Harned and co-workers (8-10) have defined it in terms of molalities of the participating species, including H ions: Ks = mHmHCO3/mCO2. In contrast, Hastings and Sendroy have defined an apparent constant in which acidity is expressed as H ion activity: K'1 = aHmHCO3/mCO2. These constants differ by a factor gamma H, the activity coefficient of H ions at the prevailing ionic strength. Therefore, pK'1 is greater than pKs by an amount equal to -log gamma H, which, at mu = 0.16 M, is approximately 0.1. It is important that the correct value for the apparent dissociation constant or its logarithmic form be entered in the mass action expression or in the Henderson-Hasselbalch equation in order to prevent significant errors in the computation by means of these equations of quantities that cannot be directly measured. Specifically, for the derivation of bicarbonate concentration from PCO2 and pH (-log aH), pK'1 is to be used and not an uncorrected pKs.

Solution pH That Minimizes Self-Association of Three Monoclonal Antibodies Is Strongly Dependent on Ionic Strength

2012 ◽  
Vol 9 (4) ◽  
pp. 744-751 ◽  
Author(s):  
Shantanu V. Sule ◽  
Jason K. Cheung ◽  
Valentyn Antochshuk ◽  
Amardeep S. Bhalla ◽  
Chakravarthy Narasimhan ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Ionic Strength ◽  
Solution Ph ◽  
Self Association
Sign in / Sign up

Export Citation Format

Share Document