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Liu L, Liu KK. Capillary force in adhesive contact between hydrogel microspheres. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Li M, Shi L, Wang X. Physical mechanisms behind the wet adhesion: From amphibian toe-pad to biomimetics. Colloids Surf B Biointerfaces 2021; 199:111531. [PMID: 33383551 DOI: 10.1016/j.colsurfb.2020.111531] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/01/2020] [Accepted: 12/06/2020] [Indexed: 10/22/2022]
Abstract
Some amphibians, such as tree frogs, torrent frogs, newts, are able to climb or attach to wet slippery smooth surfaces, even in a vertical or overhanging state, by their reliable reversible adhesions developed on the epidermal of toe pads. It is widely believed that such outstanding function originates from the possible factors of the specialized evolutions of surficial micro/nanostructures, the chemical components of secreted mucus, the solid-liquid behavior of epidermal and the bulk softness of toe pads. In this review, we summarize the main physical mechanisms of these factors behaving underlying the wet adhesion of toe pads from the researches on biological models to artificial counterparts. The discussion of the organism attachments, the interfacial physical forces and the switchable strategies for artificial wet adhesion are also included. The paper gives a deeply, comprehensively understanding of the characters of wet adhesives on amphibians, which performs necessarily for the new strategies of exploring artificial adhesive surfaces.
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Affiliation(s)
- Meng Li
- School of Mechanical Engineering, Anhui University of Technology, Ma'anshan, 243032, China; International Science and Technology Cooperation Base for Intelligent Equipment Manufacturing in Special Service Environment, Ma'anshan, 243032, China; Anhui Province Key Laboratory of Special and Heavy Load Robot, Ma'anshan, 243032, China
| | - Liping Shi
- School of Mechanical Engineering, Anhui University of Technology, Ma'anshan, 243032, China; International Science and Technology Cooperation Base for Intelligent Equipment Manufacturing in Special Service Environment, Ma'anshan, 243032, China; Anhui Province Key Laboratory of Special and Heavy Load Robot, Ma'anshan, 243032, China.
| | - Xiaolei Wang
- College of Mechanical & Electrical Engineering, Nanjing University of Aeronautics & Astronautics, Nanjing, 210016, China.
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Xiao C, Chen C, Yao Y, Liu H, Chen L, Qian L, Kim SH. Nanoasperity Adhesion of the Silicon Surface in Humid Air: The Roles of Surface Chemistry and Oxidized Layer Structures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:5483-5491. [PMID: 32357012 DOI: 10.1021/acs.langmuir.0c00205] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The interfacial adhesion between silicon oxide surfaces is normally believed to be governed by the surface chemistry of the topmost surface affecting the water contact angle and hydrogen bonding interactions. In the case of a silicon wafer, the physical structure of the native oxide at the surface can vary drastically depending on the aging process; thus, not only the surface chemistry but also the history of surface treatment can also have a profound impact on nanoasperity adhesion. This study reports the effect of aging conditions (ambient air, liquid water, and liquid ethanol) on the nanoasperity adhesion behaviors of a silicon surface. When the silicon surface is kept in liquid alcohol, the surface remains hydrophobic, and adhesion in ambient air can be explained with the capillary effect of the liquid meniscus condensed around the annulus of the nanoasperity contact. When the silicon surface is oxidized in ambient air, the surface gradually becomes hydrophilic, and the strongly hydrogen-bonded water network of adsorbed water plays a dominant role in the nanoasperity interfacial adhesion force. When the silicon surface is aged in liquid water, the interfacial adhesion force measured in ambient air is significantly larger than the value predicted from the theoretical model based on the water contact angle and the hydrogen bonding interaction at the topmost surface. This is because the surface layer oxidized in liquid water is gel-like and thus can swell upon uptake of water from the humid air. To fully encompass all these behaviors, a solid-adsorbate-solid model predicting the adhesion force is developed by introducing a fitting parameter β, which can be adjusted depending on the adsorbed water structure and the swelling capacity of the oxidized surface layer.
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Affiliation(s)
- Chen Xiao
- Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China
- Department of Chemical Engineering and Materials Research Institute, The Pennsylvania State University, University Park, State College, Pennsylvania 16802, United States
| | - Chao Chen
- Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China
| | - Yangyang Yao
- Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China
| | - Hongshen Liu
- Department of Chemical Engineering and Materials Research Institute, The Pennsylvania State University, University Park, State College, Pennsylvania 16802, United States
| | - Lei Chen
- Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China
| | - Linmao Qian
- Tribology Research Institute, State Key Laboratory of Traction Power, Southwest Jiaotong University, Chengdu 610031, China
| | - Seong H Kim
- Department of Chemical Engineering and Materials Research Institute, The Pennsylvania State University, University Park, State College, Pennsylvania 16802, United States
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Xie L, Cui X, Gong L, Chen J, Zeng H. Recent Advances in the Quantification and Modulation of Hydrophobic Interactions for Interfacial Applications. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:2985-3003. [PMID: 32023067 DOI: 10.1021/acs.langmuir.9b03573] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Hydrophobic interaction is responsible for a variety of colloidal phenomena, which also plays a key role in achieving the desired characteristics and functionalities for a wide range of interfacial applications. In this feature article, our recent advances in the quantification and modulation of hydrophobic interactions at both solid/water and air/water interfaces in different material systems have been reviewed. On the basis of surface forces apparatus (SFA) measurements of hydrophobic polymers (e.g., polystyrene), a three-regime hydrophobic interaction model that could satisfactorily encompass the hydrophobic interaction with different ranges was proposed. In addition, the atomic force microscope (AFM) coupled with various techniques such as the colloidal probe, the electrochemical process, and force mapping were employed to quantify the hydrophobic interaction from different perspectives. For the hydrophobic interactions involving deformable bubbles, the bubble probe AFM combined with reflection interference contrast microscopy (RICM) was used to simultaneously measure the interaction force and spatiotemporal evolution of the thin film drainage process between air bubbles and hydrophobized mica surfaces in an aqueous medium. The studies on the interactions of air bubbles with self-assembled monolayers (SAMs) demonstrated that the range of hydrophobic interactions does not always increase monotonically with the hydrophobicity of interacting surfaces as characterized by the static water contact angle; viz., surfaces with similar hydrophobicity can exhibit different ranges of hydrophobic interaction, while surfaces with different hydrophobicities can exhibit a similar range of hydrophobic interactions. It is found that the hydrophobic interaction can be modulated by tuning the surface nanoscale structure and chemistry. Moreover, the long-range "hydrophilic" attraction that resembles the hydrophobic interaction was discovered between water droplets and polyelectrolyte surfaces in an oil medium, on the basis of which polyelectrolyte coating materials were designed for oil cleaning, oil/water separation, and demulsification. The interfacial applications, remaining challenges, and future perspectives of hydrophobic interactions are discussed.
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Affiliation(s)
- Lei Xie
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Xin Cui
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Lu Gong
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Jingsi Chen
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Hongbo Zeng
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
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5
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Multiscale analysis of viscoelastic properties, topography and internal structure of a biodegradable thermo-responsive shape memory polyurethane. POLYMER 2020. [DOI: 10.1016/j.polymer.2020.122273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Chlanda A, Kijeńska-Gawrońska E, Zdunek J, Swieszkowski W. Internal nanocrystalline structure and stiffness alterations of electrospun polycaprolactone-based mats after six months of in vitro degradation. An atomic force microscopy assay. J Mech Behav Biomed Mater 2019; 101:103437. [PMID: 31557662 DOI: 10.1016/j.jmbbm.2019.103437] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 08/15/2019] [Accepted: 09/15/2019] [Indexed: 12/15/2022]
Abstract
Biodegradable electrospun nanofibrous scaffolds for bone tissue engineering applications have been extensively studied as they can provide attractive open-worked architecture resembling natural extracellular matrix, with tunable physical and mechanical properties enhancing positive cellular response. For this purpose, electrospun mats were tested in terms of morphology, mechanical and physical properties, degradation kinetics and related phenomena occurring in micro- and nanoscale. However, detailed description of internal nanostructures of electrospun mats and their changes related to in vitro degradation is still missing. In this manuscript, we report qualitative and quantitative evaluation of internal lamellar nanostructure of electrospun fibrous scaffolds made of pristine polycaprolactone and composite with polymeric matrix and nanoceramic (hydroxyapatite) filler during in vitro degradation. Morphological and mechanical studies performed with an atomic force microscope were followed by scanning electron microscope imaging and X-Ray diffraction. The results suggest degradation-dependent alteration of both organization and thickness of nano-scaled lamellas recorded with atomic force microscope. Moreover, changes of the material's internal structure were followed by enhanced stiffness and higher crystallinity of electrospun fibers.
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Affiliation(s)
- Adrian Chlanda
- Warsaw University of Technology, Faculty of Materials Science and Engineering, Woloska 141, 02-507, Warsaw, Poland.
| | - Ewa Kijeńska-Gawrońska
- Warsaw University of Technology, Faculty of Materials Science and Engineering, Woloska 141, 02-507, Warsaw, Poland
| | - Joanna Zdunek
- Warsaw University of Technology, Faculty of Materials Science and Engineering, Woloska 141, 02-507, Warsaw, Poland
| | - Wojciech Swieszkowski
- Warsaw University of Technology, Faculty of Materials Science and Engineering, Woloska 141, 02-507, Warsaw, Poland
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Effect of crystal plane orientation on tribochemical removal of monocrystalline silicon. Sci Rep 2017; 7:40750. [PMID: 28084433 PMCID: PMC5233974 DOI: 10.1038/srep40750] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 12/12/2016] [Indexed: 11/08/2022] Open
Abstract
The effect of crystal plane orientation on tribochemical removal of monocrystalline silicon was investigated using an atomic force microscope. Experimental results indicated that the tribochemical removal of silicon by SiO2 microsphere presented strong crystallography-induced anisotropy. Further analysis suggested that such anisotropic tribochemical removal of silicon was not dependent on the crystallography-dependent surface mechanical properties (i.e., hardness and elastic modulus), but was mainly attributed to various atomic planar density and interplanar spacing in different crystal planes. Phenomenological results speculated that higher density of silicon atom could promote the formation of Si-O-Si bonds between the SiO2 microsphere and silicon substrate, resulting in more severe tribochemical material removal. Larger interplanar spacing with smaller energy barrier facilitated the rupture of the Si-Si network with the help of mechanical shearing stress, which caused more serious wear of the silicon surface. The results may help understand the material removal mechanism of silicon and provide useful knowledge for chemical mechanical polishing.
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Qian J, Lin J, Shi M. Combined dry and wet adhesion between a particle and an elastic substrate. J Colloid Interface Sci 2016; 483:321-333. [DOI: 10.1016/j.jcis.2016.08.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 08/15/2016] [Accepted: 08/19/2016] [Indexed: 11/30/2022]
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McCracken JM, Badea A, Kandel ME, Gladman AS, Wetzel DJ, Popescu G, Lewis JA, Nuzzo RG. Programming Mechanical and Physicochemical Properties of 3D Hydrogel Cellular Microcultures via Direct Ink Writing. Adv Healthc Mater 2016; 5:1025-39. [PMID: 26924676 DOI: 10.1002/adhm.201500888] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 01/28/2016] [Indexed: 11/12/2022]
Abstract
3D hydrogel scaffolds are widely used in cellular microcultures and tissue engineering. Using direct ink writing, microperiodic poly(2-hydroxyethyl-methacrylate) (pHEMA) scaffolds are created that are then printed, cured, and modified by absorbing 30 kDa protein poly-l-lysine (PLL) to render them biocompliant in model NIH/3T3 fibroblast and MC3T3-E1 preosteoblast cell cultures. Spatial light interference microscopy (SLIM) live cell imaging studies are carried out to quantify cellular motilities for each cell type, substrate, and surface treatment of interest. 3D scaffold mechanics is investigated using atomic force microscopy (AFM), while their absorption kinetics are determined by confocal fluorescence microscopy (CFM) for a series of hydrated hydrogel films prepared from prepolymers with different homopolymer-to-monomer (Mr ) ratios. The observations reveal that the inks with higher Mr values yield relatively more open-mesh gels due to a lower degree of entanglement. The biocompatibility of printed hydrogel scaffolds can be controlled by both PLL content and hydrogel mesh properties.
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Affiliation(s)
- Joselle M. McCracken
- School of Chemical Sciences; University of Illinois Urbana-Champaign; Urbana IL 61801 USA
| | - Adina Badea
- School of Chemical Sciences; University of Illinois Urbana-Champaign; Urbana IL 61801 USA
| | - Mikhail E. Kandel
- Department of Electrical and Computer Engineering; University of Illinois Urbana-Champaign; Urbana IL 61801 USA
| | - A. Sydney Gladman
- Wyss Institute; School of Engineering and Applied Sciences; Harvard University; Cambridge MA 02138 USA
| | - David J. Wetzel
- School of Chemical Sciences; University of Illinois Urbana-Champaign; Urbana IL 61801 USA
| | - Gabriel Popescu
- Department of Electrical and Computer Engineering; University of Illinois Urbana-Champaign; Urbana IL 61801 USA
| | - Jennifer A. Lewis
- Wyss Institute; School of Engineering and Applied Sciences; Harvard University; Cambridge MA 02138 USA
| | - Ralph G. Nuzzo
- School of Chemical Sciences; University of Illinois Urbana-Champaign; Urbana IL 61801 USA
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10
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Image analysis measurements of particle coefficient of restitution for coal gasification applications. POWDER TECHNOL 2013. [DOI: 10.1016/j.powtec.2013.06.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bouffard J, Cabana A, Chaouki J, Bertrand F. Experimental investigation of the effect of particle cohesion on the flow dynamics in a spheronizer. AIChE J 2012. [DOI: 10.1002/aic.13955] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- J. Bouffard
- Dept. of Chemical Engineering; École Polytechnique de Montréal; QC H3C 3A7 Canada
| | - A. Cabana
- Dept. of Chemical Engineering; École Polytechnique de Montréal; QC H3C 3A7 Canada
| | - J. Chaouki
- Dept. of Chemical Engineering; École Polytechnique de Montréal; QC H3C 3A7 Canada
| | - F. Bertrand
- Dept. of Chemical Engineering; École Polytechnique de Montréal; QC H3C 3A7 Canada
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Leite FL, Bueno CC, Da Róz AL, Ziemath EC, Oliveira ON. Theoretical models for surface forces and adhesion and their measurement using atomic force microscopy. Int J Mol Sci 2012. [PMID: 23202925 PMCID: PMC3497299 DOI: 10.3390/ijms131012773] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The increasing importance of studies on soft matter and their impact on new technologies, including those associated with nanotechnology, has brought intermolecular and surface forces to the forefront of physics and materials science, for these are the prevailing forces in micro and nanosystems. With experimental methods such as the atomic force spectroscopy (AFS), it is now possible to measure these forces accurately, in addition to providing information on local material properties such as elasticity, hardness and adhesion. This review provides the theoretical and experimental background of afs, adhesion forces, intermolecular interactions and surface forces in air, vacuum and in solution.
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Affiliation(s)
- Fabio L. Leite
- Nanoneurobiophysics Research Group, Department of Physics, Chemistry and Mathematics, Federal University of São Carlos (UFSCar), P.O. Box 3031, CEP 18052-780, Sorocaba, São Paulo, Brazil; E-Mails: (C.C.B.); (A.L.D.R.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +55-015-3229-6014; Fax: +55-015-3229-5902
| | - Carolina C. Bueno
- Nanoneurobiophysics Research Group, Department of Physics, Chemistry and Mathematics, Federal University of São Carlos (UFSCar), P.O. Box 3031, CEP 18052-780, Sorocaba, São Paulo, Brazil; E-Mails: (C.C.B.); (A.L.D.R.)
| | - Alessandra L. Da Róz
- Nanoneurobiophysics Research Group, Department of Physics, Chemistry and Mathematics, Federal University of São Carlos (UFSCar), P.O. Box 3031, CEP 18052-780, Sorocaba, São Paulo, Brazil; E-Mails: (C.C.B.); (A.L.D.R.)
| | - Ervino C. Ziemath
- Institute of Geosciences and Exact Sciences, São Paulo State University (UNESP), P.O. Box 178, CEP 13550-970, Rio Claro, São Paulo, Brazil; E-Mail:
| | - Osvaldo N. Oliveira
- Institute of Physics of São Carlos, University of São Paulo (USP), P.O. Box 369, CEP 13560-970, São Carlos, São Paulo, Brazil; E-Mail:
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Bouffard J, Bertrand F, Chaouki J, Giasson S. Control of particle cohesion with a polymer coating and temperature adjustment. AIChE J 2012. [DOI: 10.1002/aic.13765] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Moore NW. Adhesion hysteresis from interdependent capillary and electrostatic forces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:3678-3684. [PMID: 21395292 DOI: 10.1021/la200043a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Adhesion hysteresis commonly occurs at the nanoscale in humid atmospheres, yet mechanisms are not entirely understood. Here, the adhesion forces between silicon (111) oxide surfaces and tungsten oxide probes have been examined using interfacial force microscopy. The results show that the adhesion forces during surface approach and separation differ not only in magnitude but also in mechanism, arising mainly from capillary and electrostatic forces, respectively. Surface contact leads to a transient intersurface potential on dewetting. This mechanism of adhesion hysteresis differs in not relying singly on hysteretic wetting. Furthermore, by biasing the surfaces, nonadditivity is demonstrated between the capillary and electrostatic forces at the onset of condensation. These results hold important implications on the interpretation of force in nanoprobe geometries in humid atmospheres.
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Affiliation(s)
- Nathan W Moore
- Radiation Effects Research Department, Sandia National Laboratories, P.O. Box 5800, MS-1159, Albuquerque, New Mexico 87185, United States.
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Xu D, Liechti KM, Ravi-Chandar K. Mechanical probing of icelike water monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:12870-12873. [PMID: 19845370 DOI: 10.1021/la9023629] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Direct measurements of the normal force interactions between a mica-tungsten contact pair at various humidity levels reveal the presence of repulsive forces at about 0.5 nm before intimate contact. Such repulsive interactions begin to appear above 20% RH and are fully developed in the range of 38-45% RH. Using the DMT model of contact, a reduced elastic modulus of approximately 6.7 GPa is extracted from these repulsive interactions and attributed to the presence of icelike water on mica at room temperature. The collapse of such structures was also inferred from the measurements.
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Affiliation(s)
- Dewei Xu
- Research Center for the Mechanics of Solids, Structures and Materials, Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712, USA
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Pailler-Mattei C, Nicoli S, Pirot F, Vargiolu R, Zahouani H. A new approach to describe the skin surface physical properties in vivo. Colloids Surf B Biointerfaces 2009; 68:200-6. [DOI: 10.1016/j.colsurfb.2008.10.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 09/22/2008] [Accepted: 10/01/2008] [Indexed: 10/21/2022]
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17
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On scale dependence in friction: Transition from intimate to monolayer-lubricated contact. J Colloid Interface Sci 2008; 318:507-19. [DOI: 10.1016/j.jcis.2007.09.086] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Accepted: 09/29/2007] [Indexed: 11/16/2022]
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