since density is considered as one of the most important numerical indices to explain quantitative values of a plant community by affecting on many aspects and activity of ecosystem, on the other hand, awareness about plants distribution pattern in environment is an essential preparation for measurement and study of vegetative cover, therefore, in this research determination of density and dist...

In this study, in situ strength of concrete was determined through compression test of cores drilled out from laboratory cast beams. The apparent porosity and pore size distribution of the same concrete were determined through mercury intrusion porosimetry, performed on small-drilled cores. The normal-strength concrete mixes used in the experimental investigation were designed to exhibit a wide...

The determination of porosity heterogeneity within hydrocarbon reservoirs is important because cost-effective, efficient production of hydrocarbons depends on accurate knowledge of reserve estimates, and hydrocarbon distribution. A new magnetic resonance imaging (MRI) technique, based on the conical SPRITE (Single-Point Ramped Imaging with T1 Enhancement) MRI method is capable of revealing the ...

Porous materials are lightweight, flexible and resistant to hairline cracks, so today with the development of technology porous structure produced for use in various industries. This structure widely use in beams, plates and shells. The purpose of this paper is to investigate the effect of porosity in axial symmetry in bending and buckling load sheet for analysis. For this purpose, a circular p...

The substitution of matrix permeability for fracture permeability to simplify the simulation of complex fracture systems requires a radically different treatment of transport in the matrix. The spatial distribution of pressure is reasonably well described by inclusion of only the major fractures. Transport of tracer and heat, however, depends on a detailed knowledge of fluid velocities. These v...

Composite electrodes containing active materials, carbon and binder are widely used in lithium-ion batteries. Since the electrode reaction occurs preferentially in regions with lower resistance, reaction distribution can be happened within composite electrodes. We investigate the relationship between the reaction distribution with depth direction and electronic/ionic conductivity in composite e...

In order to investigate the influence of the vertical variation of porosity on open-channel flow with submerged vegetation, vertical non-homogeneous stumps and stems in submerged vegetation flow are simulated with truncated cones in a laboratory flume. First, porosity is defined as a function of water depth. A new governing equation for vegetation flow is established on the basis of the poroela...

Mercury intrusion is frequently used for the characterization of porous materials, giving assess to parameters such as porosity and pore size distribution as well as density (skeletal and bulk). In the pulp and paper technology field, measurements of wood porosity are important, for instance to anticipate the liquor impregnation ability in the pulping stage. With regard to pulp and paper, poros...

In the die-casting process, the formation of pores in components is unavoidable. This porosity has a harmful effect on the strength and pressure tightness of die castings. To eliminate the porosity in components, its predominant cause has to be identified as being due to either shrinkage or gas. In practice, however, it is frequently difficult to tell the difference between porosity due to shri...

A novel tissue scaffold design technique has been proposed with controllable heterogeneous architecture design suitable for additive manufacturing processes. The proposed layer-based design uses a bi-layer pattern of radial and spiral layer consecutively to generate functionally gradient porosity, which follows the geometry of the scaffold. The proposed approach constructs the medial region fro...