自扩散系数作为热力学因子的函数
M Sampayo Puelles1, M Hoyuelos1
1<a href="https://ror.org/009d3ws08">Instituto de Investigaciones Físicas de Mar del Plata</a> (IFIMAR-CONICET), Departamento de Física, Facultad de Ciencias Exactas y Naturales, <a href="https://ror.org/055eqsb67">Universidad Nacional de Mar del Plata</a>, Deán Funes 3350, 7600 Mar del Plata, Argentina.
Physical review. E
|August 20, 2024
概括
这项研究引入了一种新的流体扩散模型,使用热力学因素而不是过度. 该模型准确地预测了硬球和具有一致参数的伦纳德-斯气体的自我扩散.
科学领域:
- 热力学是一种热力学.
- 流体动力学 流体动力学
- 统计力学 统计力学
背景情况:
- 对于密集流体的现有理论往往缺乏广泛适用于不同类型或度的粒子.
- 罗森菲尔德的理论将自我扩散系数与过量联系在一起,但需要采取更一般的方法.
研究的目的:
- 开发一种新的理论,用于密集流体中的自我扩散.
- 利用热力学因素,特别是过剩的化学潜力,作为扩散理论的基础.
- 创建一个适用于各种相互作用潜力的模型,而无需对参数进行调整.
主要方法:
- 开发了一个基于热力学因素和过量化学潜力的理论模型.
- 通过对硬球进行分子动力学模拟来验证模型.
- 通过对Lennard-Jones气体进行模拟,测试了模型的可转移性.
主要成果:
- 该模型成功地与使用两个自由参数的硬球模拟数据相匹配.
- 同样的参数准确地预测了伦纳德-斯气体的扩散,证明了模型的可转移性.
- 该模型对描述实验数据,特别是在高密度系统中,显示出有希望的结果.
结论:
- 拟议的模型为密集流体扩散提供了一个更普遍适用的方法.
- 使用热力学因素提供了一个强大的框架,超越了特定的相互作用潜力.
- 该模型在硬球体和莱纳德-斯系统中的成功表明了更广泛应用的潜力,包括实验数据分析,如自扩散.
相关概念视频
Extraction: Partition and Distribution Coefficients
2.3K
The distribution law or Nernst's distribution law is the law that governs the distribution of a solute between two immiscible solvents. This law, also known as the partition law, states that if a solute is added to the mixture of two immiscible solvents at a constant temperature, the solute is distributed between the two solvents in such a way that the ratio of solute concentrations in the solvents remains constant at equilibrium.
For extracting a solute from an aqueous phase into an...
For extracting a solute from an aqueous phase into an...
2.3K
Thermodynamics: Activity Coefficient
1.4K
Activity is the measure of the effective concentration of the species in solution. It can be expressed as the product of the molar concentration of the species and its activity coefficient. The activity coefficient is a dimensionless quantity and depends on the total ionic strength of the solution.
The activity coefficient is a measure of the deviation from ideal behavior. When the ionic strength of the solution is minimal, the activity coefficient of an ionic species is close to unity, making...
The activity coefficient is a measure of the deviation from ideal behavior. When the ionic strength of the solution is minimal, the activity coefficient of an ionic species is close to unity, making...
1.4K
Factors Affecting Activity Coefficient
774
The extended Debye-Hückel equation indicates that the activity coefficient of an ion in an aqueous solution at 25°C depends on three partially interdependent properties: the ionic strength of the solution, the charge of the ion, and the ion size.
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
774
Behavior of Gas Molecules: Molecular Diffusion, Mean Free Path, and Effusion
28.7K
Although gaseous molecules travel at tremendous speeds (hundreds of meters per second), they collide with other gaseous molecules and travel in many different directions before reaching the desired target. At room temperature, a gaseous molecule will experience billions of collisions per second. The mean free path is the average distance a molecule travels between collisions. The mean free path increases with decreasing pressure; in general, the mean free path for a gaseous molecule will be...
28.7K
Diffusion on Chromatography Columns
498
In column chromatography, when an analyte is introduced as a narrow band at the top of the column, the solutes begin to separate and broaden, developing a Gaussian profile. This broadening occurs due to various factors, such as longitudinal diffusion.
Longitudinal diffusion occurs when the solute molecules in the mobile phase diffuse from the more concentrated center of the chromatographic band to the more dilute regions on either side, both towards and against the flow direction. This...
Longitudinal diffusion occurs when the solute molecules in the mobile phase diffuse from the more concentrated center of the chromatographic band to the more dilute regions on either side, both towards and against the flow direction. This...
498
Maxwell-Boltzmann Distribution: Problem Solving
1.4K
Individual molecules in a gas move in random directions, but a gas containing numerous molecules has a predictable distribution of molecular speeds, which is known as the Maxwell-Boltzmann distribution, f(v).
This distribution function f(v) is defined by saying that the expected number N (v1,v2) of particles with speeds between v1 and v2 is given by
This distribution function f(v) is defined by saying that the expected number N (v1,v2) of particles with speeds between v1 and v2 is given by
1.4K


