Kinetic modelling of the photocatalytic inactivation of bacteria

2010 ◽  
Vol 61 (6) ◽  
pp. 1547-1553 ◽  
Author(s):  
Javier Marugán ◽  
Rafael van Grieken ◽  
Alberto E. Cassano ◽  
Orlando M. Alfano
Keyword(s):  
Kinetic Model ◽  
Kinetic Parameters ◽  
Catalyst Concentration ◽  
Kinetic Modelling ◽  
Kinetic Constant ◽  
Water Disinfection ◽  
Radiation Absorption ◽  
Simple Modification ◽  
Model Based ◽  
Photocatalytic Inactivation

This work analyzes the kinetic modelling of the photocatalytic inactivation of E. coli in water using different types of kinetic models; from an empirical equation to an intrinsic kinetic model including explicit radiation absorption effects. Simple empirical equations lead to lower fitting errors, but require a total of 12 parameters to reproduce the results of four inactivation curves when the catalyst concentration was increased. Moreover, these parameters have no physical meaning and cannot be extrapolated to different experimental conditions. The use of a pseudo-mechanistic model based on a simplified reaction mechanism reduces the number of required kinetic parameters to 6, being the kinetic constant the only parameter that depends on the catalyst concentration. Finally, a simple modification of a kinetic model based on the intrinsic mechanism of photocatalytic reactions including explicit radiation absorption effects achieved the fitting of all the experiments with only three parameters. The main advantage of this approach is that the kinetic parameters estimated for the model become independent of the irradiation form, as well as the reactor size and its geometrical configuration, providing the necessary information for scaling-up and design of commercial-scale photoreactors for water disinfection.

Conversion of Synthesis Gas into Light Hydrocarbons. Modelling of the Catalytic Reaction Network

2004 ◽  
Vol 2 (1) ◽  
Author(s):  
Louis Hagey ◽  
Hugo Ignacio de Lasa
Keyword(s):  
Kinetic Model ◽  
Kinetic Parameters ◽  
Gas Phase ◽  
Statistical Methods ◽  
Synthesis Gas ◽  
Catalytic Reaction ◽  
Reaction Network ◽  
Light Hydrocarbons ◽  
Model Based

This study considers a bi-functional catalyst for the conversion of synthesis gas into valuable light hydrocarbons. Catalysts are tested in a well-mixed Berty reactor. The effects of phosphorous additions on the overall catalyst performance including C5+ fractions and hydrocarbon yields are evaluated. The data obtained is very useful for establishing the validity of a kinetic model based on the gas phase observable species and to determine the various kinetic parameters of this model using statistical methods.

scholarly journals Kinetic modelling of Pt/γ-Al2O3–Cl catalysts formulation changes in n-heptane reforming

2021 ◽  
Author(s):  
Olivier Said-Aizpuru ◽  
Florent Allain ◽  
Aurélie Dandeu ◽  
Fabrice Diehl ◽  
David Farrusseng ◽  
...  
Keyword(s):  
Experimental Data ◽  
Free Energy ◽  
Kinetic Model ◽  
Kinetic Modelling ◽  
Linear Free Energy Relationships ◽  
Model Based ◽  
Linear Free Energy ◽  
Energy Relationships ◽  
Heptane Reforming

A common n-heptane reforming lumped kinetic model based on linear free energy relationships was developed on experimental data acquired over 19 Pt/γ-Al2O3–Cl catalysts presenting different formulations and support crystallite morphologies.

scholarly journals Optimization and Kinetic Modelling of The Enzymatic Hydrolysis of Oil Palm Petioles

2017 ◽  
Vol 2 (6) ◽  
pp. 439
Author(s):  
Efri Mardawatia ◽  
Dwi Wahyudha Wira ◽  
M. Djali ◽  
Fetriyuna Fetriyuna ◽  
Edi Suryadi
Keyword(s):  
Enzymatic Hydrolysis ◽  
Kinetic Model ◽  
Kinetic Parameters ◽  
Oil Palm ◽  
Kinetic Modelling ◽  
Raw Material ◽  
Surface Response Method ◽  
Response Method ◽  
Menten Kinetic ◽  
Hydrolysis Of

Oil palm petiole is  the solid waste  of the crude palm oil industry.  It contains about 35% cellulose, 18% hemicellulose and 22-25% lignin.  During hydrolysis   lingo celllulosic, cellulose and hemicellulose are gradually degraded into fermentable sugars, such as glucose and xylose. Enzymatic hydrolysis of oil palm petioleby xylanase could be an effective biotechnological process, since it can be performed at ambient temperature and pressure. Further glucose and xylose can be used as raw material for the production of a wide variety of chemicals such as xylitol and bioethanol. The aim of this study wasto examine the optimum conditions needed for the enzymatic hydrolysis  of oil palm petioles, particularly temperature and pH. A surface Response Method Methodologies  (RSM) by central composite design (CCD) was employed to obtain  the optimum xylose concentration.   The dynamics of enzymatic hydrolysis   process was modelled using the Michaelis Menten kinetic model with kinetic parameters obtained from   experimental data. The results of this study lead to an enhanced process of the enzymatic hydrolysis of oil palm petiole, whichwas shown to follow the Michaelis Menten kinetic  model and the kinetic parameters including Km and Vm were obtained, they were 6.433 g/L  andVm= 0.042 g/L/min. The optimum hydrolysis condition wereobserved to be at temperature 50oC and pH 4.8. Keywords: enzymatic hydrolysis; glucose; kinetic modelling; oil palm petioles; xylose

scholarly journals Variability in Estimated Modelled Insulin Secretion

2021 ◽  
pp. 193229682199112
Author(s):  
Jennifer J. Ormsbee ◽  
Hannah J. Burden ◽  
Jennifer L. Knopp ◽  
J. Geoffrey Chase ◽  
Rinki Murphy ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Kinetic Parameters ◽  
Pancreatic Beta Cells ◽  
Compartment Model ◽  
Interquartile Range ◽  
Cumulative Distribution ◽  
Model Framework ◽  
Intravenous Glucose ◽  
C Peptide ◽  
Model Based

Background: The ability to measure insulin secretion from pancreatic beta cells and monitor glucose-insulin physiology is vital to current health needs. C-peptide has been used successfully as a surrogate for plasma insulin concentration. Quantifying the expected variability of modelled insulin secretion will improve confidence in model estimates. Methods: Forty-three healthy adult males of Māori or Pacific peoples ancestry living in New Zealand participated in an frequently sampled, intravenous glucose tolerance test (FS-IVGTT) with an average age of 29 years and a BMI of 33 kg/m2. A 2-compartment model framework and standardized kinetic parameters were used to estimate endogenous pancreatic insulin secretion from plasma C-peptide measurements. Monte Carlo analysis (N = 10 000) was then used to independently vary parameters within ±2 standard deviations of the mean of each variable and the 5th and 95th percentiles determined the bounds of the expected range of insulin secretion. Cumulative distribution functions (CDFs) were calculated for each subject for area under the curve (AUC) total, AUC Phase 1, and AUC Phase 2. Normalizing each AUC by the participant’s median value over all N = 10 000 iterations quantifies the expected model-based variability in AUC. Results: Larger variation is found in subjects with a BMI > 30 kg/m2, where the interquartile range is 34.3% compared to subjects with a BMI ≤ 30 kg/m2 where the interquartile range is 24.7%. Conclusions: Use of C-peptide measurements using a 2-compartment model and standardized kinetic parameters, one can expect ~±15% variation in modelled insulin secretion estimates. The variation should be considered when applying this insulin secretion estimation method to clinical diagnostic thresholds and interpretation of model-based analyses such as insulin sensitivity.

Model-based analysis of coupled equilibrium-kinetic processes: indirect kinetic studies of thermodynamic parameters using the dynamic data

The Analyst ◽  
2015 ◽  
Vol 140 (9) ◽  
pp. 3121-3135
Author(s):  
Fereshteh Emami ◽  
Marcel Maeder ◽  
Hamid Abdollahi
Keyword(s):  
Kinetic Model ◽  
Thermodynamic Parameters ◽  
Kinetic Models ◽  
Kinetic Studies ◽  
Dynamic Data ◽  
Model Based ◽  
Kinetic Processes ◽  
Model Based Analysis

Schematic of intertwined equilibrium-kinetic model at time = 0,1,2…T when both equilibrium and kinetic models are solved explicitly.

Model-based analyses of the cesium dynamics in the small mesotrophic reservoir Pond 4. II. Development of a rate-based kinetic model

2018 ◽  
Vol 189 ◽  
pp. 266-281
Author(s):  
Hyojoon Jeong ◽  
Vivien J. Miller ◽  
Thomas G. Hinton ◽  
Thomas E. Johnson ◽  
John E. Pinder
Keyword(s):  
Kinetic Model ◽  
Model Based

Kinetic modelling of microalgal growth and fucoxanthin synthesis in photobioreactor

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Xiaojuan Zhang ◽  
Junru Zhao ◽  
Jie Zhang ◽  
Shijing Su ◽  
Luqiang Huang ◽  
...  
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Kinetic Parameters ◽  
Kinetic Modelling ◽  
Inhibitory Effect ◽  
Rate Equations ◽  
Phosphorus Concentration ◽  
Model Output ◽  
Nitrogen And Phosphorus ◽  
Nitrogen Phosphorus

Abstract This paper presented a mathematical model to describe the production of fucoxanthin by alga Thalassiosira weissflogi ND-8 in photobioreactor. Our interest was focused on characterizing the effects of nitrogen and phosphorus on the growth of microalgae and on the synthesis of fucoxanthin. The rate equations of microalgal growth, fucoxanthin synthesis and substrate consumptions were formulated. Kinetic parameters of the model and their sensitivities with respect to model output were estimated. The predicted results were compared with experimental data, which showed that this model closely agrees with actual experiment and is able to reflect the growth and metabolism characteristics of microalgae. Our results also indicated that nitrogen plays a major role in the synthesis of fucoxanthin, and the synthesis of fucoxanthin is partially linearly related to the consumption of nitrogen. Phosphorus is primarily consumed in the growth and metabolism of microalgal cells, while excessive phosphorus concentration has an inhibitory effect on the growth of microalgae.

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