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Lee, M. (author), Davidovikj, D. (author), Sajadi, B. (author), Siskins, M. (author), Alijani, F. (author), van der Zant, H.S.J. (author), Steeneken, P.G. (author)
Despite theoretical predictions that graphene should be impermeable to all gases, practical experiments on sealed graphene nanodrums show small leak rates. Thus far, the exact mechanism for this permeation has remained unclear, because different potential leakage pathways have not been studied separately. Here, we demonstrate a sealing method...
journal article 2019
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Schaich, M. (author), Cama, J. (author), Al Nahas, K. (author), Sobota, Diana (author), Sleath, Hannah (author), Jahnke, Kevin (author), Deshpande, S.R. (author), Dekker, C. (author), Keyser, Ulrich F. (author)
The low membrane permeability of candidate drug molecules is a major challenge in drug development, and insufficient permeability is one reason for the failure of antibiotic treatment against bacteria. Quantifying drug transport across specific pathways in living systems is challenging because one typically lacks knowledge of the exact...
journal article 2019
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Li, K. (author), Stroeven, P. (author), Le, L.B.N. (author)
A novel methodology is described for porosimetry as well as for water transport through the pore system in dynamic DEM-based virtual cementitious materials. The pore network topology, the pore size distribution and the pore connectivity are assessed on the basis of a robotics-inspired pore delineation method and star volume measurements....
journal article 2015
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Zhubayev, A. (author), Ghose, R. (author), Jihai, Y. (author), Jun, C. (author), Borodin, I. (author), Sanders, M. (author), Lim, T.K. (author), Menkiti, H. (author)
In this study, we first estimate seismic velocity and attenuation dispersion from a comprehensive zero-offset vertical seismic profile (VSP) data acquired in China. These results, combined with openhole data acquired at the same location, provide experimental evidence that the seismic attenuation in rocks is dominated by a fluid-flow mechanism....
journal article 2013
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Wang, X. (author), Xing, F. (author), Zhang, M. (author), Han, N. (author), Qian, Z. (author)
The recovery behavior for strength and impermeability of cementitious composites embedded with organic microcapsules was investigated in this study. Mortar specimens were formed by mixing the organic microcapsules and a catalyst with cement and sand. The mechanical behaviors of flexural and compression strength were tested. The results showed...
journal article 2013
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Han, B. (author), Yang, Z. (author), Shi, X. (author), Yu, X. (author)
This paper preliminarily investigates the general transport properties (i.e., water sorptivity, water permeability, and gas permeability) of carbon-nanotube/cement composites. Carboxyl multi-walled carbon nanotubes (MWNTs) are dispersed into cement mortar to fabricate the carbon nanotubes (CNTs) reinforced cement-based composites by applying...
journal article 2012
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Zhubayev, A. (author), Ghose, R. (author)
A careful look into the pertinent models of poroelasticity reveals that in water-saturated sediments or soils, the seismic (P and S wave) velocity dispersion and attenuation in the low field-seismic frequency band (20–200 Hz) have a contrasting behavior in the porosity-permeability domain. Taking advantage of this nearly orthogonal behavior, a...
journal article 2012
document
Jonkers, H.M. (author)
A typical durability-related phenomenon in many concrete constructions is crack formation. While larger cracks hamper structural integrity, also smaller sub-millimeter sized cracks may result in durability problems as particularly connected cracks increase matrix permeability. Ingress water and chemicals can cause premature matrix degradation...
journal article 2011
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Schakel, M.D. (author), Smeulders, D. (author)
The dispersion relation for seismoelectric wave propagation in poroelastic media is formulated in terms of effective densities comprising all viscous and electrokinetic coupling effects. Using Helmholtz decomposition, two seismoelectric conversion coefficients are derived, for an incident P-wave upon an interface between a compressible fluid and...
journal article 2010
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Jardani, A. (author), Revil, A. (author), Slob, E.C. (author), Söllner, W. (author)
The interpretation of seismoelectrical signals is a difficult task because coseismic and seismoelectric converted signals are recorded simultaneously and the seismoelectric conversions are typically several orders of magnitude smaller than the coseismic electrical signals. The seismic and seismoelectric signals are modeled using a finite-element...
journal article 2009
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Chao, G.E. (author), Smeulders, D.M.J. (author), Van Dongen, M.E.H. (author)
We present an exact theory of attenuation and dispersion of borehole Stoneley waves propagating along porous rocks containing spherical gas bubbles by using the Biot theory. An effective frequency-dependent fluid bulk modulus is introduced to describe the dynamic (oscillatory) behavior of the gas bubbles. The model includes viscous, thermal, and...
journal article 2007
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Chao, G. (author), Smeulders, D.M.J. (author), Van Dongen, M.E.H. (author)
Acoustic experiments on the propagation of guided waves along water-filled boreholes in water-saturated porous materials are reported. The experiments were conducted using a shock tube technique. An acoustic funnel structure was placed inside the tube just above the sample in order to enhance the excitation of the surface modes. A fast Fourier...
journal article 2006
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Cortis, A. (author), Smeulders, D.M.J. (author), Guermond, J.L. (author), Lafarge, D. (author)
The high-frequency behavior of the fluid velocity patterns for smooth and corrugated pore channels is studied. The classical approach of Johnson et al. [J. Fluid Mech. 176, 379 (1987)] for smooth geometries is obtained in different manners, thus clarifying differences with Sheng and Zhou [Phys. Rev. Lett. 61, 1591 (1988)] and Avellaneda and...
journal article 2003
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