Chaotic flow in competitive exothermic–endothermic reaction systems

The Chemical Master Equation is a standard approach to model biochemical reaction networks. It consists of a system of linear differential equations, in which each state corresponds to a possible configuration of the reaction system, and the solution describes a time-dependent probability distribution over all configurations. The Stochastic Simulation Algorithm (SSA) is a method to simulate sample paths from this stochastic process. Both approaches are only applicable for small systems, characterized by few reactions and small numbers of molecules. For larger systems, the CME is computationally intractable due to a large number of possible configurations, and the SSA suffers from large reaction propensities. In our study, we focus on catalytic reaction systems, in which substrates are converted by catalytic molecules. We present an alternative description of these systems, called SiCaSMA, in which the full system is subdivided into smaller subsystems with one catalyst molecule each. These single catalyst subsystems can be analyzed individually, and their solutions are concatenated to give the solution of the full system. We show the validity of our approach by applying it to two test-bed reaction systems, a reversible switch of a molecule and methyltransferase-mediated DNA methylation.

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Fenton-like reaction system with an analyte-activated catfish effect for enhanced colorimetric and photothermal dopamine bioassay

The Analyst ◽

10.1039/d0an01830a ◽

2020 ◽

Author(s):

Zhengrong Niu ◽

Hong-Hong Rao ◽

Xin Xue ◽

Mingyue Luo ◽

Xiuhui Liu ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Advanced Oxidation Processes ◽

Reaction System ◽

Reactive Oxygen ◽

Advanced Oxidation ◽

Oxygen Species ◽

Reaction Systems ◽

Oxidation Processes

Fenton-like reaction systems have been proven to be more efficient as the powerful promoters in advanced oxidation processes (AOPs) due to their resultantly generated reactive oxygen species (ROS) such as...

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Quantification of Measurement and Model Effects in Monopile Foundation Scour Protection Experiments

Journal of Marine Science and Engineering ◽

10.3390/jmse9060585 ◽

2021 ◽

Vol 9 (6) ◽

pp. 585

Author(s):

Minghao Wu ◽

Leen De Vos ◽

Carlos Emilio Arboleda Chavez ◽

Vasiliki Stratigaki ◽

Maximilian Streicher ◽

...

Keyword(s):

Standard Deviation ◽

Flow Field ◽

Three Dimensional ◽

Small Scale ◽

Maximum Wave Height ◽

Chaotic Flow ◽

The Mean ◽

Scour Protection ◽

Damage Number ◽

Measurement Effects

The present work introduces an analysis of the measurement and model effects that exist in monopile scour protection experiments with repeated small scale tests. The damage erosion is calculated using the three dimensional global damage number S3D and subarea damage number S3D,i. Results show that the standard deviation of the global damage number σ(S3D)=0.257 and is approximately 20% of the mean S3D, and the standard deviation of the subarea damage number σ(S3D,i)=0.42 which can be up to 33% of the mean S3D. The irreproducible maximum wave height, chaotic flow field and non-repeatable armour layer construction are regarded as the main reasons for the occurrence of strong model effects. The measurement effects are limited to σ(S3D)=0.039 and σ(S3D,i)=0.083, which are minor compared to the model effects.

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