Water quality directly influences individual and public health. Monitoring of water supplies and their sanitation is of paramount importance. The present study aimed to determine the concentrations of fluoride, chlorine, potassium, sodium, and trihalomethanes in the drinking water of five major universities in Iran. This descriptive study was conducted during January 2016-2017. In total, 60 samples of drinking water were collected from the central kitchens of the universities, including Ferdowsi University of Mashhad (two places), Gilan University, Kerman University, Hamedan University, and Shiraz University. Water samples with polyethylene terephthalate (PET) containers were obtained from the sources and shipped to the water laboratory in standard conditions. Parameters such as fluoride, chlorine, potassium, sodium ions, and trihalomethanes were measured in accordance with the national standard methods. According to the results, fluoride levels were within normal limits in all the samples, while chlorine and potassium ions were below the standard level. Similarly, sodium ion and trihalomethanes were below the standard limit in all the samples. Although the concentrations of the studied parameters were not above the standard limit, the periodic monitoring of water chemical quality is crucial to controlling community health.

In this study, the 5052 aluminum alloy was coated by plasma electrolytic oxidation (PEO) process in the 12 g. l-1 sodium silicate (Na2SiO3. 5H2O), 2 g. l-1 potassium hydroxide (KOH) using 2 g. l-1 potassium fluoride (KF) electrolytes and also not using it. The formed films in the solutions were compared in the case of KF absence or presence in the electrolyte. The coating surface morphology was inspected using the scanning electron microscopy (SEM). Both coating composition and corrosion behavior were studied by means of X-ray diffraction (XRD) and electrochemical methods. Finally, the experimental results illustrated that having added 2 g. l-1 KF to the electrolyte, the corrosion resistance of the coating was enhanced in addition to improving the film growth rate, despite the fact that there was no significant influence, applying varied voltages.

Background: Conservative treatment of adhesive dentistry considers demineralized dentin as a bonding substrate, and utilizing silver diamine fluoride (SDF) on demineralized dentin before composite restoration, probably can be beneficial. To evaluate the effect of SDF and potassium iodide (KI) on nano leakage plus the micro tensile bond strength of composite to demineralized dentin in primary teeth. Materials and Methods: In this experimental-laboratory study, seventy-eight teeth in the micro tensile group and ninety teeth in the nano leakage group were divided into two groups with sound and demineralized dentin. Each group of teeth was divided into three separate groups. In the first group, bonding was used without pre-treatment. In the second group, the SDF was used before the bonding agent and SDF and, KI was used in the third group. Two-way ANOVA, Bonferroni's post hoc test, Mann-Whitney test and Fisher's exact test were used for data analysis. (α<0. 05) Results: The lowest mean bond strength was in the SDF and KI groups in both sound (10. 0 ± 1. 9) and demineralized (6. 8 ± 2. 3) dentin groups. Using KI significantly reduced bond strength (P <0. 05). Nano leakage in teeth with sound and demineralized dentin in both SDF and SDF and KI groups was significantly lower than in the control groups (P <0. 05). Conclusion: Using SDF does not harm composite bond strength to primary teeth, but using KI after SDF reduces composite bond strength. The use of SDF and KI significantly reduces composite nano leakage.