scholarly journals Reminiscent capillarity in subnanopores

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Irena Deroche ◽  
T. Jean Daou ◽  
Cyril Picard ◽  
Benoit Coasne
Keyword(s):  
Surface Tension ◽  
Porous Materials ◽  
Adsorption Energy ◽  
Phenomenological Model ◽  
Chemical Potential ◽  
Nanoporous Materials ◽  
Simulation Data ◽  
Pore Sizes ◽  
Fluid Surface ◽  
Molecular Scale

Abstract Fluids in large and small pores display different behaviors with a crossover described through the concept of critical capillarity. Here we report experimental and simulation data for various siliceous zeolites and adsorbates that show unexpected reminiscent capillarity for such nanoporous materials. For pore sizes D exceeding the fluid molecule size, the filling pressures p are found to follow a generic behavior kBT ln p ∼ γ/ρD where γ and ρ are the fluid surface tension and density. This result is rationalized by showing that the filling chemical potential for such ultra-small pores is the sum of an adsorption energy and a capillary energy that remains meaningful even for severe confinements. A phenomenological model, based on Derjaguin’s formalism to bridge macroscopic and molecular theories for condensation in porous materials, is developed to account for the behavior of fluids confined down to the molecular scale from simple parameters.

Measurement of Burst Pressure of Capillary Burst Valve

2010 ◽  
Author(s):  
Hong Chen ◽  
Toru Yamada ◽  
Mohammad Faghri
Keyword(s):  
Surface Tension ◽  
Solid Surface ◽  
Burst Pressure ◽  
Surface Tensions ◽  
Fluid Surface ◽  
Mechanical Components

Capillary burst valve (CBV), a counterpart to an elastomeric diaphragm microvalve, handles fluid in microchannels by capillarity. Thus, it avoids integration of mechanical components. We experimentally estimated the burst pressure, beyond which CBV cannot hold fluid, using fluids with distinct surface tensions in CBVs grafted with distinct surface constitutions in microchannels. We found that both the fluid surface tension and the solid surface constitution influence the burst pressure. The burst pressure reduces more significantly under the influence of the fluid surface tension.

Amniotic Fluid Surface Tension during Pregnancy

Neonatology ◽  
1976 ◽  
Vol 29 (1-2) ◽  
pp. 112-116 ◽  
Author(s):  
Firmino F. Rubaltelli ◽  
Mario Rondinelli ◽  
Carlo Zorzi ◽  
Sergio Saia
Keyword(s):  
Surface Tension ◽  
Amniotic Fluid ◽  
Fluid Surface

Positronium Thermalization Process in Nanoporous Materials and its Influence on the Shape of PALS Spectrum

2008 ◽  
Vol 607 ◽  
pp. 39-41
Author(s):  
Jerzy Kansy ◽  
Radosław Zaleski
Keyword(s):  
Mesoporous Silica ◽  
Pore Size Distribution ◽  
Porous Materials ◽  
Pore Size ◽  
Size Distribution ◽  
Nanoporous Materials ◽  
New Method ◽  
New Model ◽  
Conventional Models ◽  
Mcm 41

A new method of analysis of PALS spectra of porous materials is proposed. The model considers both the thermalization process of positronium inside the pores and the pore size distribution. The new model is fitted to spectra of mesoporous silica MCM-41 and MSF. The resulting parameters are compared with parameters obtained from fitting the “conventional” models, i.e. a sum of exponential components with discrete or/and distributed lifetimes.

The measurement of surface tension by means of a vertical-plate balance

1970 ◽  
Vol 23 (11) ◽  
pp. 2153 ◽  
Author(s):  
JE Lane ◽  
DO Jordan
Keyword(s):  
Surface Tension ◽  
Experimental Error ◽  
Gravitational Force ◽  
Vertical Plate ◽  
Infinite Plate ◽  
Arbitrary Cross Section ◽  
Finite Plate ◽  
Fluid Surface ◽  
Additional Force ◽  
Infinite Height

A thermodynamic analysis of the measurement of surface tension using plates with either horizontal or vertical grooves of arbitrary cross section is presented. An exact description of the behaviour of horizontal grooves in a plate of infinite width and of vertical grooves in a plate of infinite height is given. The behaviour of a plate of finite height with vertical grooves can be the same as for an infinite plate, but in most instances this is not true. An approximate analysis of a finite plate with vertical grooves is developed and the errors in the curvatures of the resulting liquid-fluid surface are evaluated. In general, it is found that a grooved plate partly immersed in liquid requires a greater force to balance it than a smooth plate of the same overall dimensions and mass and with zero contact angle against the liquid and fluid phases. The additional force required to balance the grooved plate is approximately independent of the groove orientation but increases with width (pitch) of the groove. It is shown that if the measurements are made with the bottom of the plate at the level of the liquid-fluid surface at an infinite distance from the plate, the additional force almost equals the gravitational force on the mass of liquid adhering to the plate after complete immersion and withdrawal from the liquid, the agreement improving as the groove pitch is decreased. This conclusion helps explain the good results obtained for surface tension measurements using roughened plates with scratched surfaces. The important results are checked experimentally and in most cases the agreement is within the experimental error. The only exceptions to this are the results for finite plates with vertical grooves but even then the agreement is nearly quantitative.

Permeability and Structure of Resorcinol – Formaldehyde Gels

1996 ◽  
Vol 431 ◽  
Author(s):  
G. W. Scherer ◽  
C. Alviso ◽  
R. Pekala ◽  
J. Gross
Keyword(s):  
Surface Tension ◽  
Liquid Nitrogen ◽  
Capillary Forces ◽  
Resorcinol Formaldehyde ◽  
Pore Sizes ◽  
Nitrogen Desorption ◽  
Beam Bending ◽  
Good Agreement

AbstractThe permeability (D) of resorcinol-formaldehyde (RF) gels was measured using a beam-bending technique. For gels made at various solids contents and with different catalyst contents, the permeabilities ranged over a factor of ∼50; the pore radii inferred from D varied from ∼3 to 30 nm. Pore radii obtained on RF aerogels using nitrogen desorption were severely affected by compression of the aerogel by capillary forces (resulting from the surface tension of liquid nitrogen). After correction for that effect, the desorption data were found to be in very good agreement with the pore sizes calculated from D.

scholarly journals Focused ion beam milling of self-assembled magnetic superstructures: an approach to fabricate nanoporous materials with tunable porosity

2018 ◽  
Vol 5 (6) ◽  
pp. 1211-1218 ◽  
Author(s):  
Verner Håkonsen ◽  
Gurvinder Singh ◽  
Jianying He ◽  
Zhiliang Zhang
Keyword(s):  
Porous Materials ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Nanoporous Materials ◽  
Porous Network ◽  
Novel Approach ◽  
Self Assembled ◽  
Focused Ion Beam Milling

Focused ion beam milling of self-assembled magnetic superstructures is demonstrated as a novel approach to fabricate porous materials with tunable porosity. During exposure to the ion beam, nanoparticles in the superstructure are subjected to combined milling and melting, thus merging together into a porous network.

Surface Tension and Chemical Potential at Nanoscale

2012 ◽  
pp. 2599-2599
Author(s):  
Yimei Zhu ◽  
Hiromi Inada ◽  
Achim Hartschuh ◽  
Li Shi ◽  
Ada Della Pia ◽  
...  
Keyword(s):  
Surface Tension ◽  
Chemical Potential

Partially miscible liquid systems: The density, change of volume on mixing, vapor pressure, surface tension, and viscosity in the system: aniline–hexane

1968 ◽  
Vol 46 (14) ◽  
pp. 2399-2407 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
S. C. Anand ◽  
Y. Cheng ◽  
H. P. Dzikowski ◽  
...  
Keyword(s):  
Surface Tension ◽  
Vapor Pressure ◽  
Chemical Potential ◽  
Density Change ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Pressure Surface ◽  
Anomalous Viscosity ◽  
Tension Properties ◽  
Liquid Systems

The following properties have been investigated experimentally: density, change of volume on mixing, vapor pressure, surface tension, and viscosity, at temperatures above and below the critical solution temperature. The question at issue is: How does the chemical potential, or any property dependent on chemical potential, change, at constant temperature, over a range of composition, just above the critical solution temperature? In the present case, the vapor pressure and surface tension, properties directly dependent on chemical potential, are constant within the range of experimental accuracy (which, however, may not be sufficient) over a range of concentration. The viscosity is complicated by the occurrence of anomalous viscosity. The change of volume on mixing is negative, and this is usually associated with compound formation. In all other systems investigated by us, except the system triethylamine–water, ΔV is positive. We have shown elsewhere, however, that a very stable chemical compound is formed between water and triethylamine.

scholarly journals Fluid surface tension evaluation using capillary wave measurement with optical coherence tomography

AIP Advances ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 055121
Author(s):  
Hsiao-Chuan Liu ◽  
Piotr Kijanka ◽  
Matthew W. Urban
Keyword(s):  
Surface Tension ◽  
Optical Coherence Tomography ◽  
Capillary Wave ◽  
Optical Coherence ◽  
Fluid Surface ◽  
Wave Measurement

scholarly journals Droplet spreading and permeating on the hybrid-wettability porous substrates: a lattice Boltzmann method study

Open Physics ◽  
2016 ◽  
Vol 14 (1) ◽  
pp. 483-491 ◽  
Author(s):  
Wen-Kai Ge ◽  
Gui Lu ◽  
Xin Xu ◽  
Xiao-Dong Wang
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Droplet Spreading ◽  
Small Surface ◽  
Pore Sizes ◽  
Fluid Properties ◽  
Boltzmann Method ◽  
Porous Substrates

AbstractThe spreading and permeation of droplets on porous substrates is a fundamental process in a variety of applications, such as coating, dyeing, and printing. The spreading and permeating usually occur synchronously but play different roles in the practical applications. The mechanisms of the competition between spreading and permeation is significant but still unclear. A lattice Boltzmann method is used to study the spreading and permeation of droplets on hybrid-wettability porous substrates, with different wettability on the surface and the inside pores. The competition between the spreading and the permeation processes is studied in this work from the effects of the substrate and the fluid properties, including the substrate wettability, the porous parameters, as well as the fluid surface tension and viscosity. The results show that increasing the surfacewettability and the porosity contact angle both inhibit the spreading and the permeation processes. When the inside porosity contact angle is larger than 90° (hydrophobic), the permeation process does not occur. The droplets suspend on substrates with Cassie state. The droplets are more easily to permeate into substrates with a small inside porosity contact angle (hydrophilic), as well as large pore sizes. Otherwise, the droplets are more easily to spread on substrate surfaces with small surface contact angle (hydrophilic) and smaller pore sizes. The competition between droplet spreading and permeation is also related to the fluid properties. The permeation process is enhanced by increasing of surface tension, leading to a smaller droplet lifetime. The goals of this study are to provide methods to manipulate the spreading and permeation separately, which are of practical interest in many industrial applications.

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