Water vapour adsorption and surface conductivity in solids

Awakuni, Y.; Calderwood, J.H.

doi:10.1088/0022-3727/5/5/323

Cited by 122 publications

(93 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(2) is in reasonable agreement with experiments [1,2,3,4,5,6,7,8,9,10,11,12,13]: it reproduces the exponential dependence of conductivity on humidity, particularly in the well-studied range of humidities p/p 0 > 0.3, and suggests that the humidity can span six orders of magnitude for a realistic value of the Hamaker constant H. However, for DNA our estimates yield a conductivity that is smaller than observed values by one or two orders of magnitude. This may be the result of an unrealistically low estimate of the mobility based on data for bulk water.…”

Section: Discussionsupporting

confidence: 88%

Ionic conductivity on a wetting surface

2009

View full text Add to dashboard Cite

Recent experiments measuring the electrical conductivity of DNA molecules highlight the need for a theoretical model of ion transport along a charged surface. Here we present a simple theory based on the idea of unbinding of ion pairs. The strong humidity dependence of conductivity is explained by the decrease in the electrostatic self-energy of a separated pair when a layer of water (with high dielectric constant) is adsorbed to the surface. We compare our prediction for conductivity to experiment, and discuss the limits of its applicability.

show abstract

Section: Discussionsupporting

confidence: 88%

Ionic conductivity on a wetting surface

2009

View full text Add to dashboard Cite

show abstract

“…(d) K c depends on the nature of the surface, the sorbent, the nature of the liquid surface or layer formed by the condensed sorbent, and the ambient conditions (e.g., Awakuni and Calderwood, 1972;Andrews and Larson, 1993;Forslund and Leygraf, 1997). For water vapor it is a function both of temperature and pressure and other characteristics of the water surface formed by the adsorbed water vapor (Marek and Straub, 2001;Li et al, 2001).…”

Section: Semi-empirical Model Of the Wall Boundary Conditionmentioning

confidence: 99%

Attenuation of concentration fluctuations of water vapor and other trace gases in turbulent tube flow

Massman

Ibrom²

2008

Atmos. Chem. Phys.

View full text Add to dashboard Cite

Abstract. Recent studies with closed-path eddy covariance (EC) systems have indicated that the attenuation of fluctuations of water vapor concentration is dependent upon ambient relative humidity, presumably due to sorption/desorption of water molecules at the interior surface of the tube. Previous studies of EC-related tube attenuation effects have either not considered this issue at all or have only examined it superficially. Nonetheless, the attenuation of water vapor fluctuations is clearly much greater than might be expected from a passive tracer in turbulent tube flow. This study reexamines the turbulent tube flow issue for both passive and sorbing tracers with the intent of developing a physicallybased semi-empirical model that describes the attenuation associated with water vapor fluctuations. Toward this end, we develop a new model of tube flow dynamics (radial profiles of the turbulent diffusivity and tube airstream velocity). We compare our new passive-tracer formulation with previous formulations in a systematic and unified way in order to assess how sensitive the passive-tracer results depend on fundamental modeling assumptions. We extend the passive tracer model to the vapor sorption/desorption case by formulating the model's wall boundary condition in terms of a physicallybased semi-empirical model of the sorption/desorption vapor fluxes. Finally we synthesize all modeling and observational results into a single analytical expression that captures the effects of the mean ambient humidity and tube flow (Reynolds number) on tube attenuation.

show abstract

“…22 In general, the natural environment is not completely dry, therefore usually a thin water film or island patch will adhere to solid surfaces of hydrophilic materials. 11,24 Therefore, it is necessary to investigate the dependence of CE on RH. However, for most existing CE experimental results, the amount of net charge carried on a particle was determined by measuring the charge-to-mass ratio and size distribution of bulk samples of grains in a grain flow.…”

Section: Introductionmentioning

confidence: 99%

Effect of humidity on contact electrification due to collision between spherical particles

et al. 2016

View full text Add to dashboard Cite

This paper reports an experimental study of the contact electrification (CE) that happens when glass spheres of identical materials collide under different ambient relative humidity (RH) conditions. The experimental results indicate that the net charge on a sphere from a single collision is significantly altered by varying the RH level; the charge increases with increasing RH at low humidity, and then decreases at high RH conditions. The net charge reaches a maximum in the 20%–40% RH range. To explain the dependence of the CE on RH, we propose a model which yields predictions in agreement with the experimental data. The model also reveals how CE can be affected by temperature and surface absorption energy.

show abstract

Water vapour adsorption and surface conductivity in solids

Cited by 122 publications

References 5 publications

Ionic conductivity on a wetting surface

Ionic conductivity on a wetting surface

Attenuation of concentration fluctuations of water vapor and other trace gases in turbulent tube flow

Effect of humidity on contact electrification due to collision between spherical particles

Contact Info

Product

Resources

About