introduction: water and soil retention curve is one of the most important properties of porous media to obtain in a laboratory retention curve and time associated with errors. for this reason, researchers have proposed techniques that help them to more easily acquired characteristic curve. one of these methods is the use of fractal geometry. determining the relationship between particle size di...

The response of dry and water saturated sand slugs impacting normally oriented and inclined rigid-stationary targets with four different surface coatings is measured with an emphasis on the quantification of the momentum transmitted from the slugs into the targets. The targets were coated with Alumina, PTFE, Aluminium or sand-paper layers in order to investigate the effect of varying surface ha...

Based on the forward scattering amplitude function for sand particle under the Rayleigh approximation, the calculation models of microwave attenuation and phase shift due to sand and dust particles is given in terms of lognormal size distribution. The model shows that attenuation and phase shift are found to be dependent on visibility, frequency and complex dielectric constant. Obtained results...

This paper presents the results of X-ray CT imaging of the microstructure of sand particles subjected to high pressure one-dimensional compression leading to particle crushing. A high resolution X-ray CT machine capable of in situ imaging was employed to capture images of the whole volume of a sand sample subjected to compressive stresses up to 79.3 MPa. Images of the whole sample obtained at d...

one of the important aspects of soil is, knowing the relationships between spatial features of soil and quantity in statistical model. the goal of this research is to estimate saturated hydraulic conductivity by regression and co-active neuro-fuzzy inference system (anfis) with using the parameters of bulk density, real density, porosity, fractal dimension of particle size, and clay percent, si...

A laboratory, fluidized-bed gasifier is being researched as a means to gasify feedstocks in a process to produce ethanol from biomass. Fluidization characteristics of the bed, especially minimum (Umf) and complete (Ucf) fluidization velocities, were measured because they are critical to the operation of the gasifier. Fluidization properties of sand and chopped switchgrasssand mixtures of differ...

A field study was designed to study several inorganic soil amendments as a substitute for sand in the top-dressing of an aerified, sandbased putting green. Several forms of natural zeolites, calcined clays, and diatomaceous earth were blended with sand and used to backfill aerification holes on a sand-based putting green. Several of these amendments enhanced turfgrass recovery and quality in th...

Substantial information can be gained from digital in-line holography of marine particles, eliminating depthof-field and focusing errors associatedwith standard lens-based imagingmethods.However, for the technique to reach its full potential in oceanographic research, fully unsupervised (automated) methods are required for focusing, segmentation, sizing, and classification of particles. These c...

the angle of repose of soil particles is an important factor for determining critical shear stress for initiation of soil particles motion during the erosion process. there are different methods for measuring the angle of particle repose and the result of each method is somewhat different from those of the others. sliding and fixed-base piling methods are the two most common methods in the lite...