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In aluminium‐melting operations, a dross layer containing 85% metallic Al forms on the surface of the molten aluminium bath. Therefore, a significant amount of metal is removed from the furnace with the dross. Melt losses are one of the most important economical points in the melting operations. In the first part of the present study, a series of reverbaratory furnace drosses received from several aluminium plants located in Turkey were examined to determine their compositional and structural characteristics. Following crushing and grinding operations, drosses were dimensionally classified into 5 groups. Metallic Al, Mg, Zn, Fe and SiO2 contents of each group were analyzed separately. The metallic aluminium content of the group +4 mm is found to be approximately 75% while that of −0.5 mm group is 25%. Another fundamental finding is the high Mg content present in the drosses. Furthermore, Fe and SiO2 contents increase with decreasing particle size of the dross. In the second part of the investigation, experiments were carried out on the treatment of the salty slags to obtain salt, aluminium and non‐metallic products which can be used for various purposes. Leaching and crystallization in an evaporator is employed to determine the optimum conditions for the recovery of flux from the salty slag.

Background/purpose Dual Rinse HEDP is a soft chelator which can be used simultaneously with sodium hypochlorite (NaOCl). The aim of this study is to evaluate the efficacy of Dual Rinse HEDP with different irrigation systems on removing calcium hydroxide [Ca(OH) 2 ]. Materials and methods Eighty maxillary central incisor teeth were shaped and a standard groove on the apical third of the root canal surface was prepared. The root canals were filled with Ca(OH) 2 . Samples were divided into two groups according to the solution and these two groups were divided into three subgroups based on the activation technique. In group 1 (n = 10) Ca(OH) 2 was removed using conventional irrigation with NaOCl whereas in group 2 (n = 10) conventional irrigation with NaOCl – Dual Rinse HEDP mixture was used. Group 3 (n = 15) and group 4 (n = 15) received sonic activation with the same irrigants as groups 1 and 2 respectively. In group 5 (n = 15) passive ultrasonic irrigation (PUI) was used with NaOCl while in group 6 (n = 15) the irrigant was the mixture. The amount of remaining Ca(OH) 2 in the artificial grooves were evaluated under a light microscope. Results None of the procedures managed to completely remove the Ca(OH) 2 from artificial grooves. There was no significant difference between the groups (p = 0.053). The scores were significantly lower in PUI group compared to the other techniques between NaOCl groups (p = 0.021). Conclusion Dual Rinse HEDP does not make a difference on elimination of Ca(OH) 2 . PUI is more efficient than both methods when NaOCl solution is used.

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Background/aim: Selenium (Se) is a trace element that has multiple functions. Low Se amounts in serum and hair have been reported in pediatric and adult cancer patients. The aim of our study was to evaluate Se levels in the serum, urine, and hair of pediatric cancer patients with leukemia, lymphoma, and solid tumors when compared with healthy children. Materials and methods:The concentrations of Se in the serum, hair, and urine of 32 Turkish children as healthy controls and 88 Turkish children diagnosed with acute leukemia (58), lymphoma (16), and solid tumors (14) were measured using inductively coupled plasma mass spectroscopy.Results: Se levels in the serum and hair of the children with cancer were significantly lower than those of the controls. There were no differences between the leukemia, lymphoma, and solid tumors group. On the other hand, the Se levels of the urine samples were slightly elevated in cancer patients compared with the control group. There was no marked difference in the Se levels of patients with different types of cancer. Conclusion:Se deficiency might be associated with the development of pediatric cancer. Especially in children, additional studies are needed to define whether low levels of Se may play a role in cancer pathogenesis.