Equilibrium partition coefficients in iron-based alloys

1989 ◽  
Vol 20 (2) ◽  
pp. 149-160 ◽  
Author(s):  
Thomas P. Battle ◽  
Robert D. Pehlke
2018 ◽  
Vol 33 (20) ◽  
pp. 3490-3500 ◽  
Author(s):  
Lintao Gui ◽  
Mujun Long ◽  
Huabiao Chen ◽  
Dengfu Chen ◽  
Huamei Duan ◽  
...  

Abstract


2018 ◽  
Vol 20 (11) ◽  
pp. 1593-1610 ◽  
Author(s):  
A. C. Vander Wall ◽  
P. S. J. Lakey ◽  
E. Rossich Molina ◽  
V. Perraud ◽  
L. M. Wingen ◽  
...  

Experiments, kinetics modeling and quantum chemical calculations are combined to probe both initial uptake and equilibrium partition coefficients for organic nitrates into various organic films.


2008 ◽  
Vol 51 (5) ◽  
pp. 1015-1024 ◽  
Author(s):  
Ana Paula Manera ◽  
Eliana Setsuko Kamimura ◽  
Luciana Machado Brites ◽  
Susana Juliano Kalil

Amyloglucosidase enzyme was produced by Aspergillus niger NRRL 3122 from solid-state fermentation, using deffated rice bran as substrate. The effects of process parameters (pH, temperature) in the equilibrium partition coefficient for the system amyloglucosidase - resin DEAE-cellulose were investigated, aiming at obtaining the optimum conditions for a subsequent purification process. The highest partition coefficients were obtained using 0.025M Tris-HCl buffer, pH 8.0 and 25ºC. The conditions that supplied the highest partition coefficient were specified, the isotherm that better described the amyloglucosidase process of adsorption obtained. It was observed that the adsorption could be well described by Langmuir equation and the values of Qm and Kd estimated at 133.0 U mL-1 and 15.4 U mL-1, respectively. From the adjustment of the kinetic curves using the fourth-order Runge-Kutta algorithm, the adsorption (k1) and desorption (k2) constants were obtained through optimization by the least square procedure, and the values calculated were 2.4x10-3 mL U-1 min-1 for k1 and 0.037 min-1 for k2 .


2014 ◽  
Vol 1 (4) ◽  
pp. 317-323 ◽  
Author(s):  
Antonia Praetorius ◽  
Nathalie Tufenkji ◽  
Kai-Uwe Goss ◽  
Martin Scheringer ◽  
Frank von der Kammer ◽  
...  

This perspective demonstrates the inapplicability of equilibrium partition coefficients as fate descriptors for nanoparticles.


2022 ◽  
Author(s):  
Satoshi Endo

Polyparameter linear free energy relationships (PP-LFERs) are accurate and robust models to predict equilibrium partition coefficients (K) of organic chemicals. The accuracy of predictions by a PP-LEFR depends on the composition of the respective calibration data set. It is generally expected that extrapolation outside the model calibration domain is less accurate than interpolation. In this study, the applicability domain (AD) of PP-LFERs is systematically evaluated by calculation of the leverage (h), a measure of distance from the calibration set in the descriptor space. Repeated simulations with experimental data show that the root mean squared error of predictions increases with h, and that large prediction errors (>3 SDtraining, the standard deviation of training data) occur more frequently when h exceeds the common threshold of 3 hmean, where hmean is the mean h of all training compounds. Nevetheless, analysis also shows that well-calibrated PP-LFERs with many (e.g., 100), diverse, and accurate training data are highly robust against extrapolation; extreme prediction errors (> 5 SDtraining) are rare. For such PP-LFERs, 3 hmean may be too strict as the cutoff for AD. Evaluation of published PP-LFERs in terms of their AD using 25 chemically diverse, environmentally relevant chemicals as AD probes indicated that many reported PP-LFERs do not cover organosiloxanes, per- and polyfluorinated alkylsubstances, highly polar chemicals, and/or highly hydrophobic chemicals in their AD. It is concluded that calculation of h is useful to identify model extrapolations as well as the strengths and weaknesses of the trained PP-LFERs.


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