The flow of homogeneous fluids through porous media: analogies with other physical problems

Strength and mechanical behavior of short polypropylene fiber reinforced and cement stabilized clayey soil

Nanotechnology has recently emerged as a rapidly growing field with numerous biomedical science applications. At the same time, silver has been adopted as an antimicrobial material and disinfectant that is relatively free of adverse effects. Silver nanoparticles possess a broad spectrum of antibacterial, antifungal and antiviral properties. Silver nanoparticles have the ability to penetrate bacterial cell walls, changing the structure of cell membranes and even resulting in cell death. Their efficacy is due not only to their nanoscale size but also to their large ratio of surface area to volume. They can increase the permeability of cell membranes, produce reactive oxygen species, and interrupt replication of deoxyribonucleic acid by releasing silver ions. Researchers have studied silver nanoparticles as antimicrobial agents in dentistry. For instance, silver nanoparticles can be incorporated into acrylic resins for fabrication of removable dentures in prosthetic treatment, composite resin in restorative treatment, irrigating solution and obturation material in endodontic treatment, adhesive materials in orthodontic treatment, membrane for guided tissue regeneration in periodontal treatment, and titanium coating in dental implant treatment. Although not all authorities have acknowledged the safety of silver nanoparticles, no systemic toxicity of ingested silver nanoparticles has been reported. A broad concern is their potential hazard if they are released into the environment. However, the interaction of nanoparticles with toxic materials and organic compounds can either increase or reduce their toxicity. This paper provides an overview of the antibacterial use of silver nanoparticles in dentistry, highlighting their antibacterial mechanism, potential applications and safety in clinical treatment.

https://www.dovepress.com/getfile.php?fileID=57465

The Antibacterial Mechanism of Silver Nanoparticles and Its Application in Dentistry

http://www.saetaequina.com/files/1-s2_0-S0950061811006763-main.pdf

A simple review of soil reinforcement by using natural and synthetic fibers

Physics of Flow through Porous Media

Enhanced performance of reinforced soil walls by the inclusion of short fiber

The acceleration of consolidation rate by stone columns was mostly analyzed within the framework of a basic unit cell (i.e., a cylindrical soil body around a column). A method of converting the axisymmetric unit cell into the equivalent plane-strain model would be required for two-dimensional numerical modeling of multicolumn field applications. This paper proposes two simplified conversion methods to obtain the equivalent plane-strain model of the unit cell, and investigates their applicability to multicolumn reinforced ground. In the first conversion method, the soil permeability is matched according to an analytical equation, whereas in the second method, the column width is matched based on the equivalence of column area. The validity of these methods is tested by comparison with the numerical results of unit-cell simulations and with the field data from an embankment case history. The results show that for the case of linear-elastic material modeling, both methods produce reasonably accurate long-term consolidation settlements, whereas for the case of elastoplastic material modeling, the second method is preferable as the first one gives erroneously lower long-term settlements.

Simplified Plane-Strain Modeling of Stone-Column Reinforced Ground

Nanotechnology based approaches for anti-diabetic drugs delivery.

The clogging of the void spaces within the permeable base by foreign particles can severely reduce its drainage capacity. This will, in turn, reduce the service life of the permeable base layer within the pavement. In this paper, the reduction in the vertical permeability of several permeable base mixes as a result of clogging was studied. Clogging materials used are mixtures of sand and residual soil. An empirical theoretical formulation has been derived from the Kozeny-Carmen equation in order to predict the reduction in permeability of the permeable bases. The equation has been expressed in terms of the initial vertical permeability of the permeable base specimen, porosity, amount of clogging material retained, and an experimental empirical coefficient. This coefficient is found to be dependent on the ratio of the D-sub-15 size of the permeable base to the d-sub-85 size of the clogging material and coefficient of uniformity, C-sub-u, of the clogging material. The theoretical predictions were compared with experimental results with good agreement.

Clogging Evaluation of Permeable Bases

A laboratory test to assess the clogging potential of porous asphalt mixtures is useful as part of a rational design procedure of using these mixtures for construction of pavement surface friction courses. Two prerequisites for the laboratory assessment are (a) the ability to measure an engineering parameter indicative of the mixture's drainage capacity, and (b) the availability of a repeatable procedure of introducing materials into the mixture to create clogging. A laboratory clogging test to cause deterioration in the drainage capacity of typical porous mixtures is described here. Monitoring of the changes in drainage capacity during the test is made possible by the use of recently developed equipment to measure permeability. The proposed clogging test procedure was applied to evaluate four porous asphalt mixtures. Test results suggest that the procedure was able to (a) produce significant degrees of deterioration in the drainage capacities of the mixtures, and (b) differentiate the different behaviors...

Siew-Ann Tan

Papers

Enhanced performance of reinforced soil walls by the inclusion of short fiber

Simplified Plane-Strain Modeling of Stone-Column Reinforced Ground

Nanotechnology based approaches for anti-diabetic drugs delivery.

Clogging Evaluation of Permeable Bases

Laboratory Evaluation of Clogging Potential of Porous Asphalt Mixtures