The first passage time to the equilibrium state of a first order reaction

1987 ◽  
Vol 52 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Milan Šolc
Keyword(s):  
First Passage Time ◽  
Passage Time ◽  
Order Reaction ◽  
First Order Reaction ◽  
First Passage ◽  
First Order ◽  
Second Moments ◽  
Large Systems ◽  
First Moment ◽  
Number Of Particles

The first passage time to the state of exact equilibrium (the most probable stationary state) for a first order reaction is described in terms of the probability density and the first and second moments. For large systems, the first moment is proportional to the logarithm of the number of particles in the system, while the dispersion is independent of the size of the system.

Time Necessary for Reaching Chemical Equilibrium: First Passage Time Approach

2000 ◽  
Vol 214 (2) ◽  
Author(s):  
M. Solc
Keyword(s):  
Equilibrium Constant ◽  
Chemical Equilibrium ◽  
First Passage Time ◽  
Passage Time ◽  
Order Reaction ◽  
First Order Reaction ◽  
First Passage ◽  
First Order ◽  
System Composition ◽  
Approximate Formulas

The time necessary for reaching the macroscopic chemical equilibrium is defined as the time of first passage of system composition into the state of exact chemical equilibrium. The exact and approximate formulas for the first passage time in the case of reversible first order reaction with an arbitrary value of equilibrium constant are derived.

First passage time for the state of exact chemical equilibrium

1980 ◽  
Vol 45 (3) ◽  
pp. 777-782 ◽  
Author(s):  
Milan Šolc
Keyword(s):  
Chemical Equilibrium ◽  
First Passage Time ◽  
Passage Time ◽  
The State ◽  
Recurrence Time ◽  
First Passage ◽  
First Order ◽  
The Mean ◽  
Passage Times ◽  
Number Of Particles

The establishment of chemical equilibrium in a system with a reversible first order reaction is characterized in terms of the distribution of first passage times for the state of exact chemical equilibrium. The mean first passage time of this state is a linear function of the logarithm of the total number of particles in the system. The equilibrium fluctuations of composition in the system are characterized by the distribution of the recurrence times for the state of exact chemical equilibrium. The mean recurrence time is inversely proportional to the square root of the total number of particles in the system.

FIRST-ORDER NETWORK COHERENCE AND EIGENTIME IDENTITY ON THE WEIGHTED CAYLEY NETWORKS

Fractals ◽  
2017 ◽  
Vol 25 (05) ◽  
pp. 1750049 ◽  
Author(s):  
MEIFENG DAI ◽  
XIAOQIAN WANG ◽  
YUE ZONG ◽  
JIAHUI ZOU ◽  
YUFEI CHEN ◽  
...  
Keyword(s):  
First Passage Time ◽  
Analytical Formula ◽  
Passage Time ◽  
Small Degree ◽  
Network Size ◽  
Mean First Passage Time ◽  
Weight Factor ◽  
First Passage ◽  
First Order ◽  
Definition Of

In this paper, we first study the first-order network coherence, characterized by the entire mean first-passage time (EMFPT) for weight-dependent walk, on the weighted Cayley networks with the weight factor. The analytical formula of the EMFPT is obtained by the definition of the EMFPT. The obtained results show that the scalings of first-order coherence with network size obey four laws along with the range of the weight factor. Then, we study eigentime identity quantifying as the sum of reciprocals of all nonzero normalized Laplacian eigenvalues on the weighted Cayley networks with the weight factor. We show that all their eigenvalues can be obtained by calculating the roots of several small-degree polynomials defined recursively. The obtained results show that the scalings of the eigentime identity on the weighted Cayley networks obey two laws along with the range of the weight factor.

EXACT CALCULATIONS OF FIRST-PASSAGE QUANTITIES ON A CLASS OF WEIGHTED TREE-LIKE FRACTAL NETWORKS

Fractals ◽  
2020 ◽  
Vol 28 (03) ◽  
pp. 2050042
Author(s):  
BO WU ◽  
ZHIZHUO ZHANG ◽  
WEIYI SU
Keyword(s):  
First Passage Time ◽  
Probability Generating Function ◽  
Return Time ◽  
Passage Time ◽  
Weighted Tree ◽  
First Passage ◽  
Second Moments ◽  
Analytic Expressions ◽  
Exact Calculations ◽  
First Return Time

This paper concerns the weight-dependent random walk on a class of weighted tree-like fractal networks controlled by a positive integer parameter [Formula: see text] [Formula: see text] and the weight factor [Formula: see text] [Formula: see text]. We study the first return time (FRT) of a given hub and the global first-passage time (GFPT) to a given hub on the networks. By the probability generating function method, we derive the analytic expressions of the first and second moments of FRT and GFPT. In order to evaluate the fluctuation of FRT and GFPT, we further calculate the variance and the reduced moments of FRT and GFPT.

scholarly journals On the Cumulants of the First Passage Time of the Inhomogeneous Geometric Brownian Motion

Mathematics ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 956
Author(s):  
Elvira Di Nardo ◽  
Giuseppe D’Onofrio
Keyword(s):  
Brownian Motion ◽  
First Passage Time ◽  
Reversal Potential ◽  
Passage Time ◽  
Geometric Brownian Motion ◽  
Neuronal Modeling ◽  
First Passage ◽  
Numerical Performance ◽  
First Moment ◽  
Formal Power

We consider the problem of the first passage time T of an inhomogeneous geometric Brownian motion through a constant threshold, for which only limited results are available in the literature. In the case of a strong positive drift, we get an approximation of the cumulants of T of any order using the algebra of formal power series applied to an asymptotic expansion of its Laplace transform. The interest in the cumulants is due to their connection with moments and the accounting of some statistical properties of the density of T like skewness and kurtosis. Some case studies coming from neuronal modeling with reversal potential and mean reversion models of financial markets show the goodness of the approximation of the first moment of T. However hints on the evaluation of higher order moments are also given, together with considerations on the numerical performance of the method.

First-Passage Time in a Random Vibrational System

1966 ◽  
Vol 33 (1) ◽  
pp. 187-191 ◽  
Author(s):  
A. H. Gray
Keyword(s):  
First Passage Time ◽  
Passage Time ◽  
Time To Failure ◽  
Mean Square ◽  
First Passage ◽  
One Dimensional ◽  
First Order ◽  
Vibrational System ◽  
The Mean ◽  
First Passage Problem

The first-passage problem in a random vibrational system is solved by means of approximations which convert the problem to a first-order one-dimensional Markov process. Laplace transforms are used to evaluate the mean square time to failure.

Leaching Kinetics of Atrazine and Inorganic Chemicals in Tilled and Orchard Soils

2014 ◽  
Vol 28 (2) ◽  
pp. 231-237 ◽  
Author(s):  
Lech W. Szajdak ◽  
Jerzy Lipiec ◽  
Anna Siczek ◽  
Artur Nosalewicz ◽  
Urszula Majewska
Keyword(s):  
Reaction Rate ◽  
Inorganic Compounds ◽  
Model Performance ◽  
Order Reaction ◽  
First Order Reaction ◽  
Order Kinetic ◽  
Time Data ◽  
First Order ◽  
Concentration Changes ◽  
Reaction Constants

Abstract The aim of this study was to verify first-order kinetic reaction rate model performance in predicting of leaching of atrazine and inorganic compounds (K+1, Fe+3, Mg+2, Mn+2, NH4 +, NO3 - and PO4 -3) from tilled and orchard silty loam soils. This model provided an excellent fit to the experimental concentration changes of the compounds vs. time data during leaching. Calculated values of the first-order reaction rate constants for the changes of all chemicals were from 3.8 to 19.0 times higher in orchard than in tilled soil. Higher first-order reaction constants for orchard than tilled soil correspond with both higher total porosity and contribution of biological pores in the former. The first order reaction constants for the leaching of chemical compounds enables prediction of the actual compound concentration and the interactions between compound and soil as affected by management system. The study demonstrates the effectiveness of simultaneous chemical and physical analyses as a tool for the understanding of leaching in variously managed soils.

The Kinetics of Glucose Decomposition with Sulfate Reduction in the Anaerobic Fluidized Bed Reactor

1993 ◽  
Vol 28 (2) ◽  
pp. 135-144 ◽  
Author(s):  
S. Matsui ◽  
R. Ikemoto Yamamoto ◽  
Y. Tsuchiya ◽  
B. Inanc
Keyword(s):  
Sulfate Reduction ◽  
Fluidized Bed ◽  
Kinetic Equations ◽  
Fluidized Bed Reactor ◽  
Order Reaction ◽  
First Order Reaction ◽  
First Order ◽  
Glucose Decomposition ◽  
Reaction Equations ◽  
Kinetics Of

Using a fluidized bed reactor, experiments on glucose decomposition with and without sulfate reduction were conducted. Glucose in the reactor was mainly decomposed into lactate and ethanol. Lactate was mainly decomposed into propionate and acetate, while ethanol was decomposed into propionate, acetate, and hydrogen. Sulfate reduction was not involved in the decomposition of glucose, lactate, and ethanol, but was related to propionate and acetate decomposition. The stepwise reactions were modeled using either a Monod expression or first order reaction kinetics in respect to the reactions. The coefficients of the kinetic equations were determined experimentally. The modified Monod and first order reaction equations were effective at predicting concentrations of glucose, lactate, ethanol, propionate, acetate, and sulfate along the beight of the reactor. With sulfate reduction, propionate was decomposed into acetate, while without sulfate reduction, accumulation of propionate was observed in the reactor. Sulfate reduction accelerated propionate conversion into acetate by decreasing the hydrogen concentration.

Complete monotonicity of entropy production in chemical reaction

1981 ◽  
Vol 46 (2) ◽  
pp. 452-456
Author(s):  
Milan Šolc
Keyword(s):  
Entropy Production ◽  
Equilibrium Constant ◽  
Chemical Reaction ◽  
Relative Entropy ◽  
Order Reaction ◽  
Complete Monotonicity ◽  
First Order Reaction ◽  
First Order ◽  
Completely Monotonic ◽  
Derivatives Of

The successive time derivatives of relative entropy and entropy production for a system with a reversible first-order reaction alternate in sign. It is proved that the relative entropy for reactions with an equilibrium constant smaller than or equal to one is completely monotonic in the whole definition interval, and for reactions with an equilibrium constant larger than one this function is completely monotonic at the beginning of the reaction and near to equilibrium.

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