scholarly journals Application of CO2-water-rock reaction transport simulation in NPs-CO2 flooding and storage

2021 ◽  
Author(s):  
Fuping Feng ◽  
Xu Han ◽  
Shengyuan Liu ◽  
Dong Jing ◽  
Yanxin Wang
Keyword(s):  
Chemical Reaction ◽  
Transfer Model ◽  
Co2 Flooding ◽  
Displacement Efficiency ◽  
Chemical Reaction Kinetics ◽  
Acid Fluid ◽  
Reaction Transport ◽  
And Migration ◽  
Rock Microstructure ◽  
Migration Law

Abstract As a hot issue in geological engineering, CO2 flooding and sequestration still face many challenges. Injection of nanoparticles into CO2 can improve the injectability and effective reserves of CO2. However, the migration law of the mixed fluid of CO2 and nanoparticles (NPs-CO2) in the reservoir under the condition of chemical reaction is still unclear. Based on chemical reaction kinetics, a mass transfer model of NPs-CO2 nanofluid in reservoir is established by combining the micro-pore structure change of porous media under CO2-water-rock reactions condition and the migration law of NPs-CO2 fluid. The geochemical reaction process between CO2 and reservoir and the influence of heterogeneity caused by rock microstructure on the miscibility and migration of NPs-CO2 brine fluid are simulated. The results show that the CO2-water-rock reaction increases the heterogeneity of reservoir, and the porosity and permeability are rising as a whole; the increase of reservoir heterogeneity caused by chemical reaction can makes the migration of NPs-CO2 selective. The local accumulation of NPs-CO2 in the unconnected pores will weaken the original oil displacement efficiency to some extent; in the process of CO2 sequestration, the density difference between NPs-CO2 and formation water can not only promote the miscibility of NPs-CO2-brine fluid, but also inhibit the acid fluid under buoyancy. The upward diffusion is moved to the cover layer to prevent the chemical reaction of the rocks in the cap layer, so as ensuring the permanent storage of greenhouse gases.

Normal approximations for distributions arising in the stochastic approach to chemical reaction kinetics

1981 ◽  
Vol 18 (01) ◽  
pp. 263-267 ◽  
Author(s):  
F. D. J. Dunstan ◽  
J. F. Reynolds
Keyword(s):  
Reaction Kinetics ◽  
Chemical Reactions ◽  
Chemical Reaction ◽  
Stochastic Approach ◽  
Algebraic Functions ◽  
Chemical Reaction Kinetics ◽  
Normal Approximations ◽  
Formal Solutions

Earlier stochastic analyses of chemical reactions have provided formal solutions which are unsuitable for most purposes in that they are expressed in terms of complex algebraic functions. Normal approximations are derived here for solutions to a variety of reactions. Using these, it is possible to investigate the level at which the classical deterministic solutions become inadequate. This is important in fields such as radioimmunoassay.

scholarly journals THE ENDURING VULNERABILITY OF MIGRANT DOMESTIC WORKERS IN EUROPE

2013 ◽  
Vol 62 (3) ◽  
pp. 599-627 ◽  
Author(s):  
Clíodhna Murphy
Keyword(s):  
International Law ◽  
Migrant Workers ◽  
Domestic Workers ◽  
Employment Law ◽  
The United Kingdom ◽  
Regulatory Frameworks ◽  
Labour Standards ◽  
And Migration ◽  
Migration Law ◽  
Migrant Domestic Workers

AbstractWhile the rights of domestic workers are expanding in international law, including through the adoption of the ILO Domestic Workers Convention in 2011, migrant domestic workers remain particularly vulnerable to employment-related abuse and exploitation. This article explores the intersection of the employment law and migration law regimes applicable to migrant domestic workers in the United Kingdom, France and Ireland. The article suggests that the precarious immigration status of many migrant domestic workers renders employment protections, such as they exist in each jurisdiction, largely illusory in practice for this group of workers. The labour standards contained in the Domestic Workers Convention, together with the recommendations of the UN Committee on Migrant Workers on the features of an appropriate immigration regime for migrant domestic workers, are identified as providing an alternative normative model for national regulatory frameworks.

Biocompatibility and chemical reaction kinetics of injectable, settable polyurethane/allograft bone biocomposites

2012 ◽  
Vol 8 (12) ◽  
pp. 4405-4416 ◽  
Author(s):  
Jonathan M. Page ◽  
Edna M. Prieto ◽  
Jerald E. Dumas ◽  
Katarzyna J. Zienkiewicz ◽  
Joseph C. Wenke ◽  
...  
Keyword(s):  
Reaction Kinetics ◽  
Chemical Reaction ◽  
Allograft Bone ◽  
Chemical Reaction Kinetics ◽  
Kinetics Of

scholarly journals The rate of the deoxygenation reaction limits myoglobin- and hemoglobin-facilitated O2 diffusion in cells

2012 ◽  
Vol 112 (9) ◽  
pp. 1466-1473 ◽  
Author(s):  
Volker Endeward
Keyword(s):  
Skeletal Muscle ◽  
Reaction Kinetics ◽  
Chemical Reaction ◽  
Diffusion Path ◽  
Red Cells ◽  
Cardiac Muscle Cells ◽  
Chemical Reaction Kinetics ◽  
Human Red Blood Cells ◽  
Intracellular Diffusion ◽  
O2 Diffusion

A mathematical model describing facilitation of O2 diffusion by the diffusion of myoglobin and hemoglobin is presented. The equations are solved numerically by a finite-difference method for the conditions as they prevail in cardiac and skeletal muscle and in red cells without major simplifications. It is demonstrated that, in the range of intracellular diffusion distances, the degree of facilitation is limited by the rate of the chemical reaction between myglobin or hemoglobin and O2. The results are presented in the form of relationships between the degree of facilitation and the length of the diffusion path on the basis of the known kinetics of the oxygenation-deoxygenation reactions. It is concluded that the limitation by reaction kinetics reduces the maximally possible facilitated oxygen diffusion in cardiomyoctes by ∼50% and in skeletal muscle fibers by ∼ 20%. For human red blood cells, a reduction of facilitated O2 diffusion by 36% is obtained in agreement with previous reports. This indicates that, especially in cardiomyocytes and red cells, chemical equilibrium between myoglobin or hemoglobin and O2 is far from being established, an assumption that previously has often been made. Although the “O2 transport function” of myoglobin in cardiac muscle cells thus is severely limited by the chemical reaction kinetics, and to a lesser extent also in skeletal muscle, it is noteworthy that the speed of release of O2 from MbO2, the “storage function,” is not limited by the reaction kinetics under physiological conditions.

Chemical Reaction Kinetics Pertaining to Foods

2012 ◽  
pp. 113-166 ◽  
Author(s):  
Jasim Ahmed ◽  
Kirk Dolan ◽  
Dharmendra Mishra
Keyword(s):  
Reaction Kinetics ◽  
Chemical Reaction ◽  
Chemical Reaction Kinetics

Chemical Reaction Kinetics in Solution

2004 ◽  
Author(s):  
W. Ronald Fawcett
Keyword(s):  
Reaction Kinetics ◽  
Chemical Reactions ◽  
Chemical Reaction ◽  
Physical Property ◽  
Theoretical Description ◽  
Time Range ◽  
Chemical Changes ◽  
Elementary Reactions ◽  
Chemical Reaction Kinetics ◽  
Liquid Solutions

The kinetics of chemical reactions were first studied in liquid solutions. These experiments involved mixing two liquids and following the change in the concentration of a reactant or product with time. The concentration was monitored by removing a small sample of the solution and stopping the reaction, for example, by rapidly lowering the temperature, or by following a physical property of the system in situ, for example, its color. Although the experiments were initially limited to slow reactions, they established the basic laws governing the rate at which chemical changes occur. The variables considered included the concentrations of the reactants and of the products, the temperature, and the pressure. Thus, the reacting system was examined using the variables normally considered for a system at equilibrium. Most reactions were found to be complex, that is, to be made up of several elementary steps which involved one or two reactants. As the fundamental concepts of chemical kinetics developed, there was a strong interest in studying chemical reactions in the gas phase. At low pressures the reacting molecules in a gaseous solution are far from one another, and the theoretical description of equilibrium thermodynamic properties was well developed. Thus, the kinetic theory of gases and collision processes was applied first to construct a model for chemical reaction kinetics. This was followed by transition state theory and a more detailed understanding of elementary reactions on the basis of quantum mechanics. Eventually, these concepts were applied to reactions in liquid solutions with consideration of the role of the non-reacting medium, that is, the solvent. An important turning point in reaction kinetics was the development of experimental techniques for studying fast reactions in solution. The first of these was based on flow techniques and extended the time range over which chemical changes could be observed from a few seconds down to a few milliseconds. This was followed by the development of a variety of relaxation techniques, including the temperature jump, pressure jump, and electrical field jump methods. In this way, the time for experimental observation was extended below the nanosecond range.

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