Interplay of electro-thermo-solutal advection and internal electrohydrodynamics governed enhanced evaporation of droplets

The article experimentally examines and theoretically establishes the influence of electric field on the evaporation kinetics of pendant droplets. It is observed that the evaporation of saline-pendant droplets can be augmented by the application of an external alternating electric field. The evaporation behaviour is modulated by an increase in the field strength and frequency. The classical diffusion driven evaporation model is found insufficient in predicting the improved evaporation rates. The change in surface tension due to field constraint is also unable to explain the observed physics. Consequently, the internal hydrodynamics of the droplet is investigated through particle image velocimetry. The electric field is found to induce enhanced internal advection, which improves the evaporation rates. A scaled analytical model is proposed to quantify the role of internal electrohydrodynamics, electro-thermal and electro-solutal effects. Stability maps reveal that the advection is caused nearly equally by the electro-solutal and electro-thermal effects within the droplet. The model is able to illustrate the influence played by the governing thermal and solutal Marangoni number, the electro-Prandtl and electro-Schmidt number, and the associated electrohydrodynamic number. The magnitude of the internal circulation can be predicted by the proposed model, which validates the proposed mechanism.

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Role of Ca++impurities in the evaporation kinetics of NaCl and KCl crystals

Journal of Applied Physics ◽

10.1063/1.322254 ◽

1975 ◽

Vol 46 (1) ◽

pp. 441-442 ◽

Cited By ~ 5

Author(s):

M. José Yacamán

Keyword(s):

Kinetics Of ◽

Evaporation Kinetics

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Decoding the Kinetic Limitations of Plasmon Catalysis: The Case of 4-Nitrothiophenol Dimerization

10.26434/chemrxiv.12813923 ◽

2020 ◽

Author(s):

Wouter Koopman ◽

Radwan M. Sarhan ◽

Felix Stete ◽

Clemens N. Z. Schmitt ◽

Matias Bargheer

Keyword(s):

Thermal Effects ◽

Dominant Role ◽

Relative Importance ◽

New Approach ◽

Multistep Reaction ◽

Kinetics Of ◽

Complex Organic ◽

Insight Into ◽

Unique Ability

Plasmon-mediated chemistry presents an intriguing new approach to photocatalysis. However, the reaction enhancement mechanism is not well understood. In particular, the relative importance of plasmon-generated hot charges and photoheating are strongly debated. In this article, we evaluate the influence of microscopic photoheating on the kinetics of a model plasmon-catalyzed reaction: the light-induced 4-nitrothiophenol (4NTP) to 4,4’-dimercaptoazobenzene (DMAB) dimerization. Direct measurement of the reaction temperature by nanoparticle Raman-thermometry demonstrated that the thermal effect plays a dominant role in the kinetic limitations of this multistep reaction. On the same time, no reaction is possible by dark heating to the same temperature. This shows that plasmon nanoparticles have the unique ability to enhance several steps of complex tandem reactions simultaneously. These results provide insight into the role of hot electron and thermal effects in plasmonic catalysis of complex organic reactions, which highly important for the ongoing development of plasmon based photosynthesis.

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Kinematics and Kinetics of Alternating Electric Field Induced Liquid Mass Transport on Chromium Thin Films

Nanotechnology ◽

10.1088/1361-6528/abf779 ◽

2021 ◽

Author(s):

Swapnendu Narayan Ghosh ◽

Vijayendra Shastri ◽

Debjit Sarkar ◽

Ebinesh Abraham ◽

Santanu Talukder

Keyword(s):

Thin Films ◽

Electric Field ◽

Mass Transport ◽

Liquid Mass ◽

Alternating Electric Field ◽

Kinetics Of ◽

Kinematics And Kinetics

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Role of Enthalpy and Relative Electric Permittivity in Electric Field Induced Nucleation

MRS Proceedings ◽

10.1557/opl.2012.1405 ◽

2012 ◽

Vol 1431 ◽

Author(s):

K. Kohary ◽

J. Vazquez-Diosdado ◽

P. Ashwin ◽

C. D. Wright

Keyword(s):

Electric Field ◽

Dominant Role ◽

Switching Behavior ◽

Electric Permittivity ◽

Voltage Curve ◽

Current Voltage ◽

Nucleation Model ◽

Current Voltage Curve ◽

Kinetics Of

ABSTRACTEmerging phase-change electrical memory technologies rely on the fast amorphous to crystalline transition, which is usually characterized by an ‘S-shape’ current-voltage curve. We investigate the possibility that electric field induced nucleation may play a dominant role in defining this characteristic electrical switching behavior. We derive quantitative crystallization maps to study the kinetics of the amorphous to crystalline transition in the presence of electric field contribution to the free energy and we investigate how the prediction of the electric field induced nucleation model is affected by material properties such as enthalpy and relative electric permittivity.

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Ih interacts with somato-dendritic structure to determine frequency response to weak alternating electric field stimulation

Journal of Neurophysiology ◽

10.1152/jn.00541.2017 ◽

2018 ◽

Vol 119 (3) ◽

pp. 1029-1036 ◽

Cited By ~ 9

Author(s):

Enrique H. S. Toloza ◽

Ehsan Negahbani ◽

Flavio Fröhlich

Keyword(s):

Electric Field ◽

Electric Fields ◽

Cellular Response ◽

Current Injection ◽

Field Stimulation ◽

Electric Field Stimulation ◽

Cation Current ◽

Network Oscillations ◽

Alternating Electric Field

Transcranial current stimulation (tCS) modulates brain dynamics using weak electric fields. Given the pathological changes in brain network oscillations in neurological and psychiatric illnesses, using alternating electric field waveforms that engage rhythmic activity has been proposed as a targeted, network-level treatment approach. Previous studies have investigated the effects of electric fields at the neuronal level. However, the biophysical basis of the cellular response to electric fields has remained limited. Here, we characterized the frequency-dependent response of different compartments in a layer V pyramidal neuron to exogenous electric fields to dissect the relative contributions of voltage-gated ion channels and neuronal morphology. Hyperpolarization-activated cation current (Ih) in the distal dendrites was the primary ionic mechanism shaping the model’s response to electric field stimulation and caused subthreshold resonance in the tuft at 20 ± 4 Hz. In contrast, subthreshold Ih-mediated resonance in response to local sinusoidal current injection was present in all model compartments at 11 ± 2 Hz. The frequencies of both resonance responses were modulated by Ih conductance density. We found that the difference in resonance frequency between the two stimulation types can be explained by the fact that exogenous electric fields simultaneously polarize the membrane potentials at the distal ends of the neuron (relative to field direction) in opposite directions. Our results highlight the role of Ih in shaping the cellular response to electric field stimulation and suggest that the common model of tCS as a weak somatic current injection fails to capture the cellular effects of electric field stimulation. NEW & NOTEWORTHY Modulation of cortical oscillation by brain stimulation serves as a tool to understand the causal role of network oscillations in behavior and is a potential treatment modality that engages impaired network oscillations in disorders of the central nervous system. To develop targeted stimulation paradigms, cellular-level effects must be understood. We demonstrate that hyperpolarization-activated cation current (Ih) and cell morphology cooperatively shape the response to applied alternating electric fields.

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