1
|
Pan L, Chen Y, Li Z, Xie X. Dynamical behaviors of nanodroplets impinging on solid surfaces in the presence of electric fields. NANOSCALE 2023; 15:6215-6224. [PMID: 36891750 DOI: 10.1039/d2nr06486c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The collision of droplets with solid surfaces is a common phenomenon in nature. However, droplets exhibit interesting motion states when captured by surfaces. This work investigates the dynamical behavior and the wetting condition of droplets captured by different surfaces in electric fields via molecular dynamics (MD) simulations. By adjusting the initial velocity of droplets (V0), electric field intensity (E) and directions, the spreading and wetting properties of droplets are analyzed systematically. The results indicate that the electric stretching effect occurs when a droplet strikes the solid surface in electric fields and the stretch length (ht) of droplets continuously increases with the enhancement of E. In the low field strength regime, the direction of electric fields has an effect on ht: the value of ht is larger in the case of positive electric fields as compared to negative electric fields. In the high field strength regime, the direction of electric fields makes no difference to ht: the droplet is stretched observably, and the breakdown voltage U is calculated to be 0.57 V nm-1 under both positive and negative electric fields. Droplets impacting with surfaces at initial velocities display various states. The droplet bounces off the surface regardless of the direction of electric field at V0 ≥ 1.4 nm ps-1. The maximum spreading factor βmax and ht both increase with V0 and are not affected by field directions. The simulation results are consistent with experiments, and the relationships between E, βmax, ht and V0 are proposed, which provide the theoretical basis for large-scale numerical calculations such as computational fluid dynamics.
Collapse
Affiliation(s)
- Ling Pan
- School of Advanced Manufacturing, Fuzhou University, Fuzhou Fujian 362251, China
- School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou Fujian 350108, China.
| | - Yunhui Chen
- School of Advanced Manufacturing, Fuzhou University, Fuzhou Fujian 362251, China
| | - Zhi Li
- School of Advanced Manufacturing, Fuzhou University, Fuzhou Fujian 362251, China
| | - Xuqing Xie
- School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou Fujian 350108, China.
| |
Collapse
|
2
|
Behaviors of the water droplet impacting on subcooled superhydrophobic surfaces in the electrostatic field. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2022.118282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
3
|
Tian Y, Wang H, Zhou X, Deng Q, Zhu X, Chen R, Ding Y, Liao Q. A combined experimental and numerical study on droplet-impact induced breakup and ejection behaviors in vertical electric field. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2021.116636] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
4
|
Gao D, Yao D, Leist SK, Fei Y, Zhou J. Mechanisms and modeling of electrohydrodynamic phenomena. Int J Bioprint 2018; 5:166. [PMID: 32782978 PMCID: PMC7415859 DOI: 10.18063/ijb.v5i1.166] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 10/17/2018] [Indexed: 11/23/2022] Open
Abstract
The purpose of this paper is to review the mechanisms of electrohydrodynamic (EHD) phenomenon. From this review, researchers and students can learn principles and development history of EHD. Significant progress has been identified in research and development of EHD high-resolution deposition as a direct additive manufacturing method, and more effort will be driven to this direction soon. An introduction is given about current trend of additive manufacturing and advantages of EHD inkjet printing. Both theoretical models and experiment approaches about the formation of cone, development of cone-jet transition and stability of jet are presented. The formation of a stable cone-jet is the key factor for precision EHD printing which will be discussed. Different scaling laws can be used to predict the diameter of jet and emitted current in different parametrical ranges. The information available in this review builds a bridge between EHD phenomenon and three-dimensional high-resolution inkjet printing.
Collapse
Affiliation(s)
- Dajing Gao
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, USA
| | - Donggang Yao
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Steven K. Leist
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, USA
| | - Yifan Fei
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, USA
| | - Jack Zhou
- Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, USA
| |
Collapse
|
5
|
Pozniak BP, Cole RB. Perspective on electrospray ionization and its relation to electrochemistry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:369-385. [PMID: 25623197 DOI: 10.1007/s13361-014-1066-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 12/08/2014] [Accepted: 12/11/2014] [Indexed: 06/04/2023]
Abstract
The phenomenon of electrospraying of liquids is presented from the perspective of the electrochemistry involved. Basics of current and liquid flow in the capillary and spray tip are discussed, followed by specifics of charging and discharging of the sprayed liquid surface. Fundamental theories and numerical modeling relating electrospray current to solution and spray parameters are described and then compared with our own experimentally obtained data. The method of mapping potentials and currents inside the electrospray capillary by using an inserted electrically-isolated small wire probe electrode is discussed in detail with illustrations from new and published data. Based on these experimentally obtained results, a new mathematical model is derived. The introduced "nonlinear resistor electrospray capillary model" divides the electrospray capillary into small sections, adds their contributions, and then, by transition to infinitely small section thickness, produces analytical formulas that relate current and potential maps to other properties of the electrospraying liquid: primarily conductivity and current density. The presentation of the model is undertaken from an elementary standpoint, and it offers the possibility to obtain quantitative information regarding operating parameters from typical analytical systems subjected to electrospray. The model stresses simplicity and ease of use; examples applying experimental data are shown and some predictions of the model are also presented. The developed nonlinear resistor electrospray capillary model is intended to provide a new quantitative basis for improving the understanding of electrochemical transformations occurring in the electrospray emitter. A supplemental material section gives full derivation of the model and discusses other consequences.
Collapse
Affiliation(s)
- Boguslaw P Pozniak
- Department of Chemistry, University of New Orleans, 2000 Lakeshore Dr., New Orleans, LA, 70148, USA
| | | |
Collapse
|
6
|
Tian D, Song Y, Jiang L. Patterning of controllable surface wettability for printing techniques. Chem Soc Rev 2013; 42:5184-209. [DOI: 10.1039/c3cs35501b] [Citation(s) in RCA: 264] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
7
|
Latham J, Bower K, Choularton T, Coe H, Connolly P, Cooper G, Craft T, Foster J, Gadian A, Galbraith L, Iacovides H, Johnston D, Launder B, Leslie B, Meyer J, Neukermans A, Ormond B, Parkes B, Rasch P, Rush J, Salter S, Stevenson T, Wang H, Wang Q, Wood R. Marine cloud brightening. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2012; 370:4217-62. [PMID: 22869798 PMCID: PMC3405666 DOI: 10.1098/rsta.2012.0086] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The idea behind the marine cloud-brightening (MCB) geoengineering technique is that seeding marine stratocumulus clouds with copious quantities of roughly monodisperse sub-micrometre sea water particles might significantly enhance the cloud droplet number concentration, and thereby the cloud albedo and possibly longevity. This would produce a cooling, which general circulation model (GCM) computations suggest could-subject to satisfactory resolution of technical and scientific problems identified herein-have the capacity to balance global warming up to the carbon dioxide-doubling point. We describe herein an account of our recent research on a number of critical issues associated with MCB. This involves (i) GCM studies, which are our primary tools for evaluating globally the effectiveness of MCB, and assessing its climate impacts on rainfall amounts and distribution, and also polar sea-ice cover and thickness; (ii) high-resolution modelling of the effects of seeding on marine stratocumulus, which are required to understand the complex array of interacting processes involved in cloud brightening; (iii) microphysical modelling sensitivity studies, examining the influence of seeding amount, seed-particle salt-mass, air-mass characteristics, updraught speed and other parameters on cloud-albedo change; (iv) sea water spray-production techniques; (v) computational fluid dynamics studies of possible large-scale periodicities in Flettner rotors; and (vi) the planning of a three-stage limited-area field research experiment, with the primary objectives of technology testing and determining to what extent, if any, cloud albedo might be enhanced by seeding marine stratocumulus clouds on a spatial scale of around 100×100 km. We stress that there would be no justification for deployment of MCB unless it was clearly established that no significant adverse consequences would result. There would also need to be an international agreement firmly in favour of such action.
Collapse
Affiliation(s)
- John Latham
- National Centre for Atmospheric Research, Boulder, CO 80301, USA
- School of Earth and Atmospheric Sciences, University of Manchester, Manchester M13 9PL
| | - Keith Bower
- School of Earth and Atmospheric Sciences, University of Manchester, Manchester M13 9PL
| | - Tom Choularton
- School of Earth and Atmospheric Sciences, University of Manchester, Manchester M13 9PL
| | - Hugh Coe
- School of Earth and Atmospheric Sciences, University of Manchester, Manchester M13 9PL
| | - Paul Connolly
- School of Earth and Atmospheric Sciences, University of Manchester, Manchester M13 9PL
| | - Gary Cooper
- Department of Engineering, University of Edinburgh, Edinburgh EH9 3JL, UK
| | - Tim Craft
- MACE, University of Manchester, Manchester M13 9PL, UK
| | - Jack Foster
- Department of Engineering, University of Edinburgh, Edinburgh EH9 3JL, UK
| | - Alan Gadian
- NCAS, SEE, University of Leeds, Leeds LS2 9JT, UK
- Author for correspondence ()
| | | | | | | | - Brian Launder
- MACE, University of Manchester, Manchester M13 9PL, UK
| | | | | | | | | | - Ben Parkes
- NCAS, SEE, University of Leeds, Leeds LS2 9JT, UK
| | - Phillip Rasch
- Climate Science, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | | | - Stephen Salter
- Department of Engineering, University of Edinburgh, Edinburgh EH9 3JL, UK
| | - Tom Stevenson
- Department of Engineering, University of Edinburgh, Edinburgh EH9 3JL, UK
| | - Hailong Wang
- Climate Science, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | | | - Rob Wood
- Department of Atmospheric Sciences, University of Washington, Seattle, WA 98105, USA
| |
Collapse
|
8
|
Stachewicz U, Dijksman JF, Burdinski D, Yurteri CU, Marijnissen JCM. Relaxation times in single event electrospraying controlled by nozzle front surface modification. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:2540-2549. [PMID: 19159191 DOI: 10.1021/la8021408] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Single event electrospraying (SEE) is a method for on-demand deposition of femtoliter to picoliter volumes of fluids. To determine the influence of the size of the meniscus on the characteristics of the single event electrospraying process, glass capillaries were used with and without an antiwetting coating comprising a self-assembled 1H,1H,2H,2H-perfluorodecyltrichlorosilane-based monolayer to control the meniscus size. A large difference was found in driving single event electrospraying from a small meniscus compared to what is needed to generate a single event electrospraying from a large meniscus. Furthermore, after studying the different time constants related to the electrical and the hydrodynamic phenomena, we are able to explain the timing limitations of the deposition process from both a small and a large meniscus. The hydrodynamic relaxation time is significantly reduced in the case of the modified capillary, and the timing of SEE, which determines the deposition time, is limited by the resistor-capacitor RC time of the electrical circuit needed to drive the SEE. We have built a model that describes the almost one-dimensional motion of the liquid in the capillary during pulsing. The model has been used to estimate the hydrodynamic relaxation times related to the meniscus-to-cone and cone-to-meniscus transitions during SEE. By confining the meniscus to the inner diameter of the nozzle, we are able to deposit a volume smaller than 5 pL per SEE.
Collapse
Affiliation(s)
- Urszula Stachewicz
- Department of Healthcare Devices and Instrumentation, Philips Research Europe, High Tech Campus, 5656 AE Eindhoven, The Netherlands.
| | | | | | | | | |
Collapse
|
9
|
Hulman M, Tajmar M. Indium ion emission from nanotube fibres. NANOTECHNOLOGY 2007; 18:495709. [PMID: 20442490 DOI: 10.1088/0957-4484/18/49/495709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The manufacture of a liquid metal ion source based on carbon nanotubes is described. Multi-wall carbon nanotubes were attached to the tip of a tungsten needle forming a fibre which was subsequently coated with a layer of indium. The onset of ion emission was observed at about 850 V, a value much lower than that for a conventional indium needle emitter. However, the nanotube fibres degrade rapidly at higher voltages and eventually disappear from the needle.
Collapse
Affiliation(s)
- Martin Hulman
- Austrian Research Centers-ARC, A-2444 Seibersdorf, Austria.
| | | |
Collapse
|
10
|
Grym J, Otevrel M, Foret F. Aerodynamic mass spectrometry interfacing of microdevices without electrospray tips. LAB ON A CHIP 2006; 6:1306-14. [PMID: 17102844 DOI: 10.1039/b605599k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A new concept for electrospray coupling of microfluidic devices with mass spectrometry was developed. The sampling orifice of the time-of-flight mass spectrometer was modified with an external adapter assisting in formation and transport of the electrosprayed plume from the multichannel polycarbonate microdevice. The compact disk sized microdevice was designed with radial channels extending to the circumference of the disk. The electrospray exit ports were formed by the channel openings on the surface of the disk rim. No additional tips at the channel exits were used. Electrospray was initiated directly from the channel openings by applying high voltage between sample wells and the entrance of the external adapter. The formation of the spatially unstable droplet at the electrospray openings was eliminated by air suction provided by a pump connected to the external adapter. Compared with the air intake through the original mass spectrometer sampling orifice, more than an order of magnitude higher flow rate was achieved for efficient transport of the electrospray plume into the mass spectrometer. Additional experiments with electric potentials applied between the entrance sections of the external adapter and the mass spectrometer indicated that the air flow was the dominant transport mechanism. Basic properties of the system were tested using mathematical modeling and characterized using ESI/TOF-MS measurements of peptide and protein samples.
Collapse
Affiliation(s)
- Jakub Grym
- Institute of Analytical Chemistry, Veveri 97, 61142 Brno, Czech Republic
| | | | | |
Collapse
|
11
|
Lazar IM, Grym J, Foret F. Microfabricated devices: A new sample introduction approach to mass spectrometry. MASS SPECTROMETRY REVIEWS 2006; 25:573-94. [PMID: 16508917 DOI: 10.1002/mas.20081] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Instrument miniaturization is one way of addressing the issues of sensitivity, speed, throughput, and cost of analysis in DNA diagnostics, proteomics, and related biotechnology areas. Microfluidics is of special interest for handling very small sample amounts, with minimal concerns related to sample loss and cross-contamination, problems typical for standard fluidic manipulations. Furthermore, the small footprint of these microfabricated structures leads to instrument designs suitable for high-density, parallel sample processing, and high-throughput analyses. In addition to miniaturized systems designed with optical or electrochemical detection, microfluidic devices interfaced to mass spectrometry have also been demonstrated. Instruments for automated sample infusion analysis are now commercially available, and microdevices utilizing chromatographic or capillary electrophoresis separation techniques are under development. This review aims at documenting the technologies and applications of microfluidic mass spectrometry for the analysis of proteomic samples.
Collapse
Affiliation(s)
- Iulia M Lazar
- Virginia Bioinformatics Institute and Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
| | | | | |
Collapse
|
12
|
Koerner T, Oleschuk RD. Porous polymer monolith assisted electrospray from a glass microdevice. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:3279-86. [PMID: 16217844 DOI: 10.1002/rcm.2181] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The coupling of a lab-on-a-chip microfluidic device to a nanoelectrospray ionization mass spectrometer has the potential to automate many routine analytical procedures and produce a powerful analytical tool. However, past coupling strategies have relied on complex manufacturing steps including drilling and etching the device to attach a capillary or building a nanospray emitter directly into the device. This study shows that a nanospray emitter can be easily fabricated using a porous polymer monolith (PPM) at the end of a glass microdevice. These devices are able to obtain a stable electrospray at a variety of flow rates (50-500 nL/min) but optimal results are obtained at lower flow rates (50-100 nL/min) compatible with electroosmotic flow processes. The PPM is photo-patterned so that it can be placed in any position within the channel of the device with no dead volume. The porous character and the hydrophobic nature of the PPM both aid in development of a stable electrospray process. Total ion current traces for the constant infusion of leucine-enkephalin and PPG show relative standard errors as low as 4%, and produce mass spectra with good signal-to-noise (S/N 43) from only 2 fmol of material. In addition, multiple experiments in a given day show good repeatability with variability as low as 13%, and the multiple flow paths inherent in the PPM limit sprayer clogging.
Collapse
Affiliation(s)
- Terry Koerner
- Department of Chemistry, Queen's University, Kingston, Ontario, Canada, K7L 3N6
| | | |
Collapse
|