nanotechnology has been shown to have promising roles in the development of various industries including the agricultural sector. the primary purpose of this study was to investigate the researchers’ attitude and the obstacle hampering the development of nanotechnology in the agricultural sector of iran. the population of this study consisted of researchers in national research centers/institut...

In this paper, the passive control of flow past a semi-circular cylinder is investigated. This control is achieved by adding a porous medium between the solid obstacle and the incompressible fluid in order to reduce drag forces and regularize the flow. A vortex-penalization method is chosen to easily model the flow in the different media. Several configurations of the porous layer are investiga...

Density or gravity currents have been always one of the main causes for sedimentation along many of the dam reservoirs. So controlling this phenomenon is very important for increasing useful life of such reservoirs. In this research study the effect of a combination of rough bed and obstacle on the control of sedimentary density current has been investigated. Experiments were conducted in a til...

density or gravity currents have been always one of the main causes for sedimentation along many of the dam reservoirs. so controlling this phenomenon is very important for increasing useful life of such reservoirs. in this research study the effect of a combination of rough bed and obstacle on the control of sedimentary density current has been investigated. experiments were conducted in a til...

The porosity of a zone can be estimated either from a single “porosity log” (sonic, density, neutron, or magnetic resonance log) or a combination of porosity logs, in order to correct for variable lithology effects in complex reservoirs. In the carbonates, mineral mixtures are primarily drawn from calcite, dolomite, and quartz (either as sand grains or as chert); anhydrite and gypsum may also o...

In industry, the porosity of petrochemical reservoirs is measured frequently by coring and is an important property when trying to determine if a site is appropriate for drilling. Porosity can also be used in waste water treatment in order to determine if a material is ideal for water purification in industrial or residential applications. The purpose of this experiment was to simulate a oil re...

Anomalous velocity and porosity are often indicators of abnormal pore pressure. It is important, therefore, to be able to link velocity to porosity and rock texture in a rational, firstprinciple-based manner. The critical porosity concept allows for building such rock physics models. Critical porosity is the porosity above which the rock can exist only as a suspension. In sandstones the critica...

In this paper, we report an analysis of pressed paper in terms of porosity and permeability. Previously, we reported a pressed paper that exhibits decreased porosity and permeability. Additionally, its applications into programmed sample delivery as well as flow rate control were reported. However, there is a need for a theoretical analysis of pressed paper in terms of porosity and permeability...

A major challenge in flow through porous media is to better understand the link between microstructure and macroscale transport. For idealised microstructures, mathematical framework of homogenisation theory can be used for this purpose. Here, we consider a two-dimensional comprising an array obstacles smooth but arbitrary shape, size spacing which vary along length medium. We use via method mu...