Many larvae and other plankton have complex and variable morphologies of unknown functional significance. We experimentally and theoretically investigated the functional consequences of the complex morphologies of larval sand dollars, Dendraster excentricus (Eschscholtz), for hydrodynamic interactions between swimming and turbulent water motion. Vertical shearing flows (horizontal gradients of ...

The reuse of mineral wastes is one of the most suitable solid wastes solutions. Throughout the world, the large of the granular aggregates used in constructions exploit natural mountain resources and rivers. Using mineral waste as a part of concrete, it can be helped to create a green environment and also contribute to sustainable development. Since the copper production process in the Sarchesh...

The production of castings by green sand moulds is a very important method for the manufacture of final products for different sectors of industry. In this green sand moulding process the quality of castings depends strongly on the quality of the mould, which in turn is determined by parameters such as the type of foundry machine, the characteristics of the moulding sand and the specifications ...

The Karazhanbas Field (KBM) is a giant shallow heavy oil field in western Kazakhstan, less than 460 m depth. It contains heavy oil (μ ~400 cP) in seven reservoir zones from several to 40 m thick in unconsolidated sands with porosities 28-32%, permeabilities of ~0.5 D, and an arkosic lithology with angular grains. There is no free gas cap, and the structure is divided into fault-controlled block...

Quantitation of the nonlinear heterogeneities in Leishmania parasites, sand fly vectors, and mammalian host relationships provides insights to better understand leishmanial transmission epidemiology towards improving its control. The parasite manipulates the sand fly via production of promastigote secretory gel (PSG), leading to the "blocked sand fly" phenotype, persistent feeding attempts, and...

The main aim of this research is to study the possible use of recycled fine aggregate made from waste rubble wall to substitute partially for the natural sand used in the production of cement and sand bricks. The bricks specimens were prepared by using 100% natural sand; they were then replaced by recycled fine aggregate at 25, 50, 75, and 100% by weight of natural sand. A series of tests was c...

Petro physics, rock physics and multi-attribute analysis have been employed in an integrated approach to delineate porosity variation across Tamag Field of Niger Delta Basin. Gamma and resistivity logs were employed to identify sand bodies and correlated across the field. Petro physical analysis was undertaken. Rock physics modelling and multi-attribute analysis were carried out. Two hydrocarbo...

[1] Wind-blown sand, or ‘saltation,’ creates sand dunes, erodes geological features, and could be a significant source of dust aerosols on Mars. Moreover, the electrification of sand and dust in saltation, dust storms, and dust devils could produce electric discharges and affect atmospheric chemistry. We present the first calculations of electric fields in martian saltation, using a numerical m...

Small sand molds for aluminum casting were produced by selective laser sintering (SLS) of pre-coated sands. A diode laser source with a rectangular laser beam spot was used to perform single and multi-layer processing tests. Subsequently, small sand molds were produced and tested in casting operations. Single layer processing was performed by changing laser power, scan rate and distance of the ...

The Amazon forest is being exploited for timber production. The harvest removes trees, used by sand flies as resting sites, and decreases the canopy, used as refuges by some hosts. The present study evaluated the impact of the timber harvest, the abundance of sand flies, and their trypanosomatid infection rates before and after selective logging. The study was accomplished in terra-firme produc...