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A set of high-copper amalgam alloys have been prepared based on the change in the ratio of copper to silver using elemental components of high purity 99.9%. The amalgamation processes were done by mixing alloy powders with mercury at a fixed ratio. Structural properties were studied using X-ray diffraction and Optical Microscopy. Also, microhardness, and compressive strength were used to study some other important mechanical properties. The prepared amalgams were compared with well-known commercial amalgams; ANA 2000 and Standalloy F. The results of X-ray diffraction showed several prime phases in alloys and amalgams whose proportions and distribution depended on the copper content in the alloy. The results of mechanical test measurements showed a linear increase in the mechanical properties with increasing copper content in the amalgams. The results were similar to the measured values of the commercial amalgam.

In this research, the light filling with titanium oxide was formed as an anti-corrosion and antibacterial antibiotic. White acrylic powder was used with its solvent after mixing it with different percentages of biologically active titanium oxide using the liquid mixing method and the ultrasound technique to obtain a homogeneous mixture free of aggregates and then was molded into special molds for the required examination. The hard surface hardness of the samples prepared using the hardness device was examined along with the test of dry sliding wear using a Pin-on-disk method, as well as the examination of the samples to resist the bacteria of tooth decay. Structural tests were performed on X-ray diffraction techniques, scanning electron microscopy technique and infrared technique. The results were interpreted based on the practical density of the prepared samples.

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Some geometric parameters affecting the performance of a wire-plate electrostatic precipitator (ESP) are investigated theoretically. A numerical model was built to investigate the influence of the discharge wire size, wire separation, collector plates spacing, and roughness factor on the ESP performance. The results show that thinner wires emit higher current than larger ones at the same applied voltage, which would be suitable for low voltage power supply to generate the desired current density at the collecting electrodes. The results also show that, as the discharge electrodes get closer, the corona gets suppressed, resulting in a diminished corona current flow. On the other hand, as the distance between electrodes increases, the total current density decreases, leading to a less efficient ESP performance. Narrow spacing between collector plates gives a better performance. With regard to the effect of the roughness factor, the results revealed that the emitted current is strongly affected by the wires physical conditions.