Bicarbonate ion concentrations

Vertical concentration profiles of (a) temperature, (b) potential density, (c) salinity, (d) O2, (e) % saturation of O2, (f) bicarbonate and TDIC, (g) carbonate alkalinity and total alkalinity, (h) pH, (i) carbonate, ( ) carbon dioxide and carbonic acid concentrations, and (k) carbonate-to-bicarbonate ion concentration ratio. Curves labeled f,p have been corrected for the effects of in-situ temperature and pressure on equilibrium speciation. Curves labeled t, 1 atm have been corrected for the in-situ temperature effect, but not for that caused by pressure. Data from 50°27.5 N, 176°13.8 W in the North Pacific Ocean on June 1966. Source From Culberson, C., and R. M. Pytkowicz (1968). Limnology and Oceanography, 13, 403-417. 

Bicarbonate ions concentration at Viriato is higher as the value of pH increases. Thus, the corrosion process and the corrosion products transformation occur to a higher pH and this can lead to changes in the corrosion mechanism and in the nature of corrosion products formed. 

Bicarbonate ion concentration is regulated mainly by excretion and synthesis in the kidneys. 

The bicarbonate ion, HC03, is a prevalent species in natural waters, ranging in concentrations up to 0.8 X 10 3. As was indicated previously, carbonate ions have the ability to form complexes with plutonium. Starik (39) mentions that, in an investigation of the adsorption of uranium, there was a decrease in the adsorption after reaching a maximum, which was explained by the formation of negative carbonate complexes. Kurbatov and co-workers (20) found that increasing the bicarbonate ion concentration in a UXi (thorium) solution decreased the amount of thorium which formed a colloid and became filterable. This again was believed to be caused by the formation of a soluble complex with the bicarbonate. 

At pH less than 3, the reaction will occur slowly enough for kinetic models to be true. Thus, a pH 2 or 7 can be utilized for the slow kinetics of atrazine oxidation by UV /ozone processes, while rapid reactions will take place at pH 12. All of the three reaction mechanisms will be affected by other variables such as temperature, pH, and bicarbonate ion concentrations. 

Barralet, J., S. Best, and W. Bonfield (1998). Carbonate substitution in precipitated hydroxyapatite An investigation into the effects of reaction temperature and bicarbonate ion concentration. J. Biomedical Materials Res. 41, 1, 79-86. 

Bicarbonate is the second largest fraction (behind Ci ) of plasma anions ( 25 mmol/L). Conventionally, it is defined to include (1) plasma bicarbonate ion, (2) carbonate, and (3) CO2 bound in plasma carbamino compounds (Figure 46-7). At the pH of blood, the plasma carbonate concentration is 25 pmol/L, which is -1/700 to 1/1000 of the total bicarbonate concentration. C02-bound carbamino compounds (RCNHCOOH) are 0.2 mmol/L in plasma and 1.5 mmol/L in erythrocytes. Actual bicarbonate ion concentration is not measured, but rather calculated from the Henderson-Hasselbalch equation as described below (and discussed in detail in Chapter 27). Also, as described in Chapter 27, the analyte usually measured in plasma is total COa, which includes bicarbonate and dissolved CO (dC02). The dC02 fraction is defined to include both the undissociated carbonic acid and physically dissolved, free CO2. At the pH of the blood, the amount of dissolved CO2 is 700 to 1000 times greater than the amount of carbonic acid and therefore... 

As the concentration of HCO3 (i.e., of metabolic CO2) in red blood cells increases, an imbalance occurs between the bicarbonate ion concentrations in the red blood cell and plasma. This osmotic imbalance causes a marked efflux of HC03 to plasma and consequent influx of Cl from plasma in order to maintain the balance of electrostatic charges. The latter osmotic influx, known as the chloride shift, is accompanied by migration of water to red blood cells. Thus, transport of metabolic CO2 in the blood occurs primarily in the form of plasma bicarbonate formed after CO2 diffuses into red blood cells. 

The observed microscopic structure or particular interparticle associations were found to correlate with bicarbonate ion concentration, although, as mentioned earlier, small concentrations of organic surfactants released by the caustic extraction process (that would also correlate with bicarbonate concentration) cannot be ruled out. Figure 25 shows MFT created without caustic [the other six lease owners (OSLO) process]. No structure comparable with that observed in the MFT from the Clark extraction process is evident in this sample despite its similar particle size distribution and weight percent solids. Kaolinite clays in deionized... 

Baravelli S, Bigi A, Ripamonti A, Roveri N, Forest E (1984) Thermal behavior of bone and synthetic hydroxylapatites submitted to magnesium interaction in aqueous medium. J Inorg Biochem 20 1-12 Barralet J, Best S, Bonfield W (1998) Carbonate substitution in precipitated hydroxylapatite an investigation into the effects of reaction temperatme and bicarbonate ion concentration. J Biomed Mater Res 41 79-86... 

Carbonate buffers are Important In regulating the pH of blood at 7.40. If the carbonic acid concentration In a sample of blood Is 0.0012 AT, determine the bicarbonate Ion concentration required to buffer the pH of blood at pH = 7.40. 

Bicarbonate alkalinity The bicarbonate ion concentration expressed in ppm as CaC03 equivalents. 

To provide a historical perspective, Earle s balanced salt solution (EBSS) [32], developed in 1943, is one of the first synthetic biomineralization media (although at the time of their development researchers did not see such solutions as versatile milieu to perform in vitro biomineralization and biomimetic synthesis studies) to mimic the ion concentrations of blood plasma without using any Tris or Hepes 2-(4-(2-hydroxyethyl)-l-piperazinyl)ethane sulphonic acid, G8H18N2O4S). Hepes, like Tris, is also not present in the human blood. EBSS solution had a HGOs (bicarbonate ion) concentration of 26.2 mM (close to that of human blood, 27 mM) and a Ga/P molar ratio of 1.8 (in stark contrast to that of human blood, which is 2.50). The pH value (7.4) of EBSS solution is identical with that of blood. 

Bicarbonate Ion Concentration and Blood pH Acidification of the Urine 572 Bicarbonate Absorption Secretion of Ammonia Respiration and Blood pH... 

The relationship between blood pH, bicarbonate ion concentration, and partial pressure of CO2 is expressed in the Henderson-Hasselbalch equation ... 

Modeling CO2 Corrosion A CO2 corrosion "worst case" model baised on an ANN approach was developed and the model validated against a large experimental database [28], An experimental databaise was used to train and test the ANN. It consisted initially of six elemental descriptors (temperature, partial CO2 pressure, ferrous and bicarbonate ion concentrations, pH, and flow velocity) and one output, i.e., the corrosion rate. The system demonstrated superior interpolation performance compared to two other well known semi-empirical models. The ANN model also demonstrated extrapolation capabilities comparable to a purely mechanistic electrochemical CO2 corrosion model. 

The higher bicarbonate ion concentration in blood makes the buffer capacity of blood greater for acid than for base, which is necessary because the products of metabolism that enter blood are mostly acidic. For example, when we exercise, our bodies produce lactic acid (HC3H5O3). The lactic acid enters the bloodstream and must be neutralized. 

Fig. 4. Species distributions (25 C, Y = 35) are shown for La (fig. 4a) and Lu (fig. 4b) as a function of pH and carbonate ion concentration. This figure was constructed assuming a total bicarbonate ion concentration...

C) and three values of pH. The bicarbonate ion concentration in this figure is equal to 2x 10" molkg... 

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