Water transfers through wood structure play a major role in wood behavior under various conditions such as drying, imbibition, sapflow, for which various problems may occur, such as shrinkage, cavitation, fracture, swelling. The physical understanding of these transfers is in some cases rather poor, as illustrated by the fact that it is still sometimes considered that the permeability of wood...
Over the last decade, the generation of organic porous (nano)materials with tunable pore sizes and desired functionalities has been the subject of increasing attention in materials science. Interest in such porous frameworks originates from the large variety of applications in which they are involved, e.g. size/shape-selective nanoreactors, monoliths for advanced chromatographic techniques,...
Soft nanoporous matter encompasses man-made materials such as compliant porous solids, intrinsically porous polymers and organic membranes as well as natural materials such as wood, bamboo, cotton and other plant-derived materials. These materials can undergo significant deformation during water adsorption because of strong coupling between the adsorption and mechanical properties. In...
Arabinoglucuronoxylan (AGX) is one of the most abundant hemicellulose of softwood. It is formed by β-1,4-linked β-D-Xylp units, partially substituted at O-2 by 4-O-Me-α-D-GlcpA and at O-3 by α-L-Araf. It has diverse potential use in many industries, such as packaging of cosmetic or pharmacy, plastic additive and bio-refinery.
Despite its versatile potential, most of the key properties of...
A common assumption in recent molecular simulation based investigations of hydrocarbon transport in kerogen is that the latter behaves as a rigid matrix [1-4]. In other words, its porosity remains relatively constant and irrespective of temperature, lithostatic (or external) pressure or fluid (or adsorption) pressure. This implies that the matrix isolates the fluid from external pressure...
We have studied mechanism of hydrogen storage in CAU-1 and CAU-8 metal organic frameworks synthesized at Christian-Albrechts-University of Kiel, Germany [1], [2]. The structures of these compounds are built from aluminum polyhedra with fully coordinated metal ions. Using various types of organic linker molecules tunable structures with channels of different geometries, but very similar...
Gas separation processes involving adsorption may have advantages over other separation methods although one drawback still remains the need for increased selectivity. A simple way to improve the selectivity of a separation process is to increase the pore confinement in the adsorbent. For instance, this can be achieved by the inclusion of large cations in the case of zeolites or by controlling...
Arsenic is one among the most hazardous contaminants present in drinking water sources. Recent increases in agricultural growth and extensive use of fertilisers in India and Bangladesh have led to the release of naturally occurring arsenic from the rocks and earth's crust, creating a major public health issue in these countries. A novel technology has been recently developed that uses...
Filtration of contaminants out of air is vital for many industrial applications. In particular, we are interested in the technology of air filtration used in vacuum cleaners produced by Dyson Ltd. In this study, we focus on predicting and improving the efficiency of the filter media used in vacuum cleaners. Filter media are usually characterized by different criteria. The first one is energy...
Flotation tests in laboratories are commonly carried out using Denver flotation cells of laboratory size. Since economical and performance impacts due to equipment age can be less obvious at a laboratory-scale than at an industrial-scale, the condition of parts of the cell is overlooked. Maintenance of damaged or old parts might not be carried out. Usually, these parts are not properly...
Creep/swelling of Shale-rocks create several problems [1] during underground drilling operations, such as stuck-pipe/drill-bit. However, creep/swelling of shale-rocks can close the gaps between rock (wellbore) and casing –therefore no cementing is needed – which can save a lot of time and money and such a “natural” closing ensures “no-leakage” during further drilling and production phases....
Oil-painted linen canvas is a well-used art support system, used for more than five centuries, where the capacity of the canvas and its wood frame to absorb water is not only an issue of dimensional stability and modified material properties, but also of durability and damage for the stiff oil paint. In effect, as water molecules are adsorbed into the hydrophilic matrix in the plant cell...
Soils and rocks are amongst all, the most challenging construction materials to be studied. Currently, the elastoplastic theory has become popular when it comes to modelling their stress-strain behavior. This is because this theory is capable of considering the material strengthening, softening, ultimate strength and residual strength. In this paper, we present an elastoplastic constitutive...
The finite deformation of an unsaturated porous medium is the result of a complex interplay between capillary effects, interfacial area propagation, pressure diffusion and large deformations of the solid skeleton. Discrete approaches provide a means to integrate the physics of capillarity with deformation. However, discrete approaches only open the road to simple cases. The authors analysed...
Several emerging problems in geotechnical and geoenvironmental engineering pose multi-physics problems involving non-isothermal processes in unsaturated soils. Properly studying these problems requires the development of models for the Soil Water Retention Curve (SWRC) to describe the constitutive behavior of unsaturated soils under non-isothermal conditions. This study aims to develop...
