Experimental study of the mechanical properties of burnt clay bricks incorporated with plastic and steel waste materials

Traditional masonry bricks are made of clay burnt under high temperatures, resulting in high energy consumption, environmental contaminations and decreased natural raw materials. In order to limit nature risks, inorganic materials have been used to make brick. Four types of materials, including fine and coarse plastic, cast iron, and iron swarf, have been used to make bricks. A total number of 64 specimens were made and tested. The tests results were presented in the form of compressive strength, rupture module, water absorption percentage, and initial water absorption ratio. The result showed that using cast iron powder caused the maximum compressive strength amongst all the samples, and was 46% larger than for the reference bricks. On the other hand, the maximum initial water absorption occurred within the first three hours, while the maximum rate was associated to samples with higher coarse plastic contents.

Influence of the Roughness of Different Materials of Plastic and Metal Pipes on the Pressure Variation in Hydraulic Curves

A hydraulic simulation in pipes allows us to analyze the hydraulic behavior under various conditions. Hydraulic experiments are essential because there are many peculiarities in the analysis of the experimental processes. Computational fluid dynamics (CFD) tools assist in this process, they allow analyzes are made under the most varied conditions. Another parameter that typically affects the behavior of hydraulic fluid under pressure is the roughness of the materials that make up the pipes. In this work, we studied the variation of pressure in water pipes made from many common materials, such as plastic, cast iron and steel. Experimental data were used for validation, and the results showed variation in the parameters of the pressure and velocity fields.

Endocranial Morphology of A.L. 444-2

The original endocast of A.L. 444-2 consisted of a single plastic cast, colored to show the original fragments (light brown) and the reconstructed missing parts (black). This we label the Rak-Kimbel endocast, which was based on the reconstruction of cranial and facial fragments. Because distortion was severe enough to interfere with morphological description and measurements, and especially the assessment of endocranial capacity, a plaster endocast was received from Yoel Rak in 1998 for purposes of modification. This newer plaster endocast formed the basis for the original endocast reconstruction done by R.L.H., who based the reconstruction on the less distorted side (left) and then doubled its water-displaced volume to achieve the final endocranial volume. As will become clear in our descriptions, this first method required several additions and subtractions to compensate for missing portions, for flash lines left from the casting process, and for distortion remaining in the reconstruction. We concluded that a more accurate reconstruction would result if the portions of the original endocast were separated from reconstructed elements and approximated on a plasticene “core” so that distortion could be effectively eliminated. The second method, which was accomplished mostly by M.S.Y. with minimal guidance from R.L.H., permitted a range of possible reconstructions of the actual brain endocast pieces and provided a range of endocast volumes. This reconstruction methodology, referred to as the “dissection method,” eliminated most of the distortion and obviated the need to correct for flash lines. Although both methods provide a final endocranial capacity very close to what must have been the actual living brain volume of A.L. 444-2, we consider the dissection method to be the more accurate one. Distortion of the endocranial cast mirrors that of the cranium. While the right parietotemporal area appears to be depressed, the left parietotemporal area shows signs of bulging in compensation. In addition, due to a gap that runs anteroposteriorly along the left temporal lobe, there is an artificial increase in the distance between the base of the endocast and its apex of about 3–8 mm on the left side.

Velocity Measurements Inside a Hemodialysis Graft In Vitro Model

Arteriovenous (AV) grafts, which provide an access site for hemodialysis, typically produce a high flow rate environment with pressure and velocity fluctuations; high and low wall shear stress, and vibration. Laser Doppler anemometry (LDA) was performed at Reynolds number (Re) 1200 on an in vitro model, which was constructed from computerized tomography (CT) images of a perfusion fixed plastic cast of a canine venous anastomosis. The results obtained were compared to numerical results and to results previously obtained with idealized in vitro models. This study showed the importance of an accurate geometry in characterizing the flow environment inside an AV graft. Good agreement between the computational fluid dynamics (CFD) and LDA was observed although differences were clearly present.