Diffusion mechanisms in under-cooled binary liquids

There is a substantial body of research that recognises the importance of analysing regional characteristics in employment and labour relations that occur in a given geographical context. However, this phenomenon has been scarcely studied from a spatial approach. This article uses a spatio-temporal panel data model to examine the spatial interactions between the gender employment gap and, some labour and socioeconomic characteristics of 727 municipalities of Andalusia, Spain, for the period 2012–2016. The results show that due to spatial diffusion mechanisms, a spatial spillover effect occurs in both the gender gap in employment and in some of the labour and socioeconomic characteristics considered. These findings may be extended to other geographic areas and can be of use for the implementation of regional policies aimed at narrowing the gender employment gap. JEL Codes: R10, J16, E24

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NH3 on anatase TiO2(101) : Diffusion mechanisms and the effect of intermolecular repulsion

Physical Review Materials ◽

10.1103/physrevmaterials.4.121601 ◽

2020 ◽

Vol 4 (12) ◽

Author(s):

Kræn C. Adamsen ◽

Esben L. Kolsbjerg ◽

Stig Koust ◽

Lutz Lammich ◽

Bjørk Hammer ◽

...

Keyword(s):

Anatase Tio2 ◽

Diffusion Mechanisms

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Continuous Demixing Transition of Binary Liquids: Finite‐Size Scaling from the Analysis of Sub‐Systems

Advanced Theory and Simulations ◽

10.1002/adts.202000235 ◽

2021 ◽

pp. 2000235

Author(s):

Yogyata Pathania ◽

Dipanjan Chakraborty ◽

Felix Höfling

Keyword(s):

Finite Size ◽

Finite Size Scaling ◽

Binary Liquids ◽

Size Scaling

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Cation ordering and oxygen transport behaviour in Sr1−3x/2LaxTiO3perovskites

Journal of Materials Chemistry A ◽

10.1039/c6ta10274c ◽

2017 ◽

Vol 5 (11) ◽

pp. 5321-5331 ◽

Cited By ~ 2

Author(s):

Paul C. M. Fossati ◽

Robin W. Grimes

Keyword(s):

Oxygen Transport ◽

Oxygen Diffusion ◽

Cation Ordering ◽

Atomistic Modelling ◽

Modelling Techniques ◽

Transport Behaviour ◽

Diffusion Mechanisms

Effects of cation ordering on oxygen diffusion mechanisms in (Sr,La)TiO3perovskites is investigated using atomistic modelling techniques.

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Diffusion Mechanisms in Sige Alloys

MRS Proceedings ◽

10.1557/proc-568-253 ◽

1999 ◽

Vol 568 ◽

Cited By ~ 11

Author(s):

Arthur F.W. Willoughby ◽

Janet M. Bonar ◽

Andrew D.N. Paine

Keyword(s):

Diffusion Processes ◽

Dopant Diffusion ◽

Elemental Silicon ◽

Self Diffusion ◽

Si Substrates ◽

Marker Layer ◽

Diffusion Mechanisms ◽

Silicon And Germanium ◽

Charged Defects

ABSTRACTInterest in diffusion processes in SiGe alloys arises from their potential in HBT's, HFET's, and optoelectronics devices, where migration over distances as small as a few nanometres can be significant. Successful modelling of these processes requires a much improved understanding of the mechanisms of self- and dopant diffusion in the alloy, although recent progress has been made. It is the purpose of this review to set this in the context of diffusion processes in elemental silicon and germanium, and to identify how this can help to elucidate behaviour in the alloy. Firstly, self diffusion processes are reviewed, from general agreement that self-diffusion in germanium is dominated by neutral and acceptor vacancies, to the position in silicon which is still uncertain. Germanium diffusion in silicon, however, appears to be via both vacancy and interstitial processes, and in the bulk alloy there is evidence for a change in dominant mechanism at around 35 percent germanium. Next, a review of dopant diffusion begins with Sb, which appears to diffuse in germanium by a mechanism similar to self-diffusion, and in silicon via monovacancies also, from marker layer evidence. In SiGe, the effects of composition and strain in epitaxial layers on Si substrates are also consistent with diffusion via vacancies, but questions still remain on the role of charged defects. The use of Sb to monitor vacancy effects such as grown-in defects by low temperature MBE, are discussed. Lastly, progress in assessing the role of vacancies and interstitials in the diffusion of boron is reviewed, which is dominated by interstitials in silicon-rich alloys, but appears to change to domination by vacancies at around 40 percent germanium, although studies in pure germanium are greatly needed.

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OH− and H3O+ Diffusion in Model AEMs and PEMs at Low Hydration: Insights from Ab Initio Molecular Dynamics

Membranes ◽

10.3390/membranes11050355 ◽

2021 ◽

Vol 11 (5) ◽

pp. 355

Author(s):

Tamar Zelovich ◽

Mark E. Tuckerman

Keyword(s):

Molecular Dynamics ◽

Fuel Cell ◽

Ab Initio ◽

Cost Effective ◽

Clean Energy ◽

Proton Exchange ◽

Ab Initio Molecular Dynamics ◽

Anion Exchange Membranes ◽

Diffusion Mechanisms ◽

Dynamics Simulations

Fuel cell-based anion-exchange membranes (AEMs) and proton exchange membranes (PEMs) are considered to have great potential as cost-effective, clean energy conversion devices. However, a fundamental atomistic understanding of the hydroxide and hydronium diffusion mechanisms in the AEM and PEM environment is an ongoing challenge. In this work, we aim to identify the fundamental atomistic steps governing hydroxide and hydronium transport phenomena. The motivation of this work lies in the fact that elucidating the key design differences between the hydroxide and hydronium diffusion mechanisms will play an important role in the discovery and determination of key design principles for the synthesis of new membrane materials with high ion conductivity for use in emerging fuel cell technologies. To this end, ab initio molecular dynamics simulations are presented to explore hydroxide and hydronium ion solvation complexes and diffusion mechanisms in the model AEM and PEM systems at low hydration in confined environments. We find that hydroxide diffusion in AEMs is mostly vehicular, while hydronium diffusion in model PEMs is structural. Furthermore, we find that the region between each pair of cations in AEMs creates a bottleneck for hydroxide diffusion, leading to a suppression of diffusivity, while the anions in PEMs become active participants in the hydronium diffusion, suggesting that the presence of the anions in model PEMs could potentially promote hydronium diffusion.

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