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Purpose: Acrylic denture base tends to fracture frequently during their service due to poor strength. The surface roughness of denture base is a critical property because denture base with rough surface will cause accumulation of food particles ,thereby leading plaque retention. Microbes such as candida albicans are seen inhabitating the surface. Materials and Methods: Conventional heat cure denture base reins(DPI) and heat cure denture base resin with incorporation of 15wt% aluminium oxide was studied in two groups with 20 samples each. A mold of size 65 mm × 10 mm × 3 mm (ISO Standard) was obtained by investing brass rectangles. About forty specimens were prepared. Specimens were divided into two groups (n = 20) coded A and B. Group A was the control group (n = 20) without addition of aluminum oxide. Group B was the experimental group (n = 20) with addition of 15 wt % aluminum oxide. All the specimens were stored in distilled water for 14 days. The flexural strength was measured using a three-point bending test in a universal testing machine, and the surface roughness was measured using contact-type profilometer. Results: Incorporation of 15wt% aluminum oxide leads to a significant increase in flexural strength and surface roughness of conventional heat-cure denture base resin. [ABSTRACT FROM AUTHOR]

For better blast furnace performance, there has always been a need for better quality raw materials like sinter, lump ore, and pellets. Among these raw materials the usage of sinter in blast furnace is at higher side compared to other iron bearing materials. As the quality of sinter product improves, its usage in blast furnaces also increases. Iron ore fines are the main source for sinter making. To improve the sinter properties it is necessary to provide good quality of iron ore fines. Due to depletion of high grade iron ore resources, goethite and limonitic ore content in iron ore fines is expected to increase gradually. Usually limonitic and goethite ore are associated with higher alumina and LOI. The conventional sintering process is one of the well established processes for high quality hematite ore. It does not fully respond to the low grade iron ore associated with goethite and limonite. This has led to deterioration in sinter properties and productivity. In recent years the improvement in the quasi-particle structure with the granulation process is an effective method for improving sinter quality and productivity. To improve the sinter quality and productivity for low grade iron ore fines, different granulation processes like the conventional one, and other two advanced granulation processes like coke breeze, and flux & coke breeze coating granulation were studied in detail by conducting laboratory pot grate sintering experiments. From the test results it was found that sinter productivity, physical and metallurgical properties of the sinter improved with flux & coke breeze coating granulation process compared to conventional and coke breeze coating granulation process. Proper selection of the granulation time is very important to achieve the desired sinter properties. In the present work detailed laboratory experiments have been carried out by varying the coating time from 30s to 110s to study the influence of flux & coke breeze coating granulation time on mineralogy, productivity, physical, and metallurgical properties of sinter. With a coating granulation time of 50s, higher productivity, higher yield, and stronger sinter (higher T.I) with lower RDI and -5mm size sinter were achieved. [ABSTRACT FROM AUTHOR]

The article presents on a study on the effect of alumina in iron ore on sinter properties and productivity in the conventional and selective granulation sintering process. The selective granulation process was used with ore fines of different alumina levels while the conventional granulation process was used with the same levels. It was revealed that increase in alumina levels also increase the pore size and number of pores in both process but the conventional pore shape become more irregular.