In this paper, chemical analysis of slag from abandoned medieval mine in Gornji Potočari, Srebrenica municipality was described. Total of 10 metals were analyzed: chromium, copper, cadmium, nickel, cobalt, zinc, silver, manganese, iron and lead. Traces of chromium, nickel, cobalt, copper, manganese and cadmium in the samples point to the fact that the starting ore also contained these elements. Results showed high content of iron (25.11–33.12%), lead (5.90–10.77%) and zinc (1.16–6.79%). The content of silver had a positive correlation with the content of lead, which is in favor of the initial hypothesis that the starting ore was galena (PbS). High zinc content indicates that the sphalerite (Zn,Fe)S was also used in the process, whereas iron most likely emanates from pyrite (FeS2). Galena and sphalerite can be found in Srebrenica area in large quantities. The results of the analysis show that the site was used for the production of lead and silver (from primary ores), intensive mining activity during the Middle Ages, and the latest date that we can account for slag origin is the end of the 16th century.
ABSTRACT White-rot and brown-rot fungi degrade structural components of wood. The possibility of PAHs degradation by these fungi is based on their structural similarity with lignin (primary degraded by white-rot fungus) and hemi-cellulose and cellulose (degraded by brown-rot fungus). This study compares biodegradation level of polycyclic aromatic hydrocarbons (PAHs) using the two ligninolytic fungi Hypoxylon fragiforme (HF) and Coniophora puteana (CP). The biodegradation of ten PAHs was performed in liquid media (2% w/v in water, of malt extract and 0.5% w/v in water, solution of glucose). After 3 weeks of incubation, non-degraded pollutants were extracted by benzene and determined using the GC/MS technique. Both fungi completely degraded 1-methylnaphthalene and 2-methynaphthalene. 1-methylfluorene was also completely degraded by HF while about 62.7% of it was degraded by CP. The remaining PAHs were degraded by HF and CP fungi, respectively, in the following percentages: 82.0 and 79.0 for acenaphthene; 90.3 and 80.0 for acenaphthylene; 17.8 and 41.3 for anthracene; 5.8 and 53.8 for 1,2-benzanthracene; 0.0 and 20.3 for benzo(k)fluoranthene; 50.5 and 15.8 for byphenil; 85.8 and 74.8 for fluorene; 65.5 and 47.5 for phenanthrene; 42.5 and 50.5 for pyrene.
Abstract Simultaneous adsorption of heavy metals in complex multi metal system is insufficiently explored. This research gives results of key process parameters optimization for simultaneous removal of Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution (batch system). New lemon peel-based biomaterial was prepared and characterized by infrared spectroscopy with Fourier transformation (FTIR), scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS), while the quantification of metals was made by atomic absorption spectrometry (AAS). Simultaneous removal of seven metals ions was favorable at pH 5 with 300 mg/50 mL solid-liquid phase ratio, within 60 min at room temperature with total obtained adsorption capacity of 46.77 mg g−1. Kinetic modeling showed that pseudo-second order kinetic and Weber-Morris diffusion models best describe the adsorption mechanism of all seven heavy metals onto lemon peel.
High-intensity training is becoming more popular nowadays when people have less time to engage in prolonged physical activity. Expertly led high intensity training is a safe way to achieve desired fitness goals. The aim of the study was to check if there were significant changes in the concentrations of sodium, potassium, calcium, magnesium, zinc, iron and copper in the blood and urine of twelve trainees after a short but intense training. Blood and urine sampling was performed before and after high intensity training where bodyweight exercises and exercises with external load were used. Statistical analysis was performed using paired t-test (2-tailed) with α=0.05 as statistical significance. The results obtained showed that the measured mineral concentrations varied as a result of intense physical activity, but these variations were small and did not have a general trend of increase or decrease of analyzed mineral content. Based on these results, it can be concluded that, from the standpoint of the mineral concentrations loss, short high-intensity training is safe for the trainee’s health.
Abstract The goal of this study was to determine the content of 12 metals in 23 samples of teeth from two cities in Bosnia and Herzegovina (B&H): Sarajevo, a capital city with heavy traffic, industrial facilities, and long periods of smog during winter and Bihac, a picturesque small city, with no industrialization, settled among vivid national park and rivers. The teeth were separated into enamel and dentin. Dissolution of samples was performed in concentrated HNO3 with the addition of H2O2 followed by flame atomic absorption spectroscopy (FAAS) analysis. The results showed expected high contents of Ca, Na, Mg, and K, while elevated contents of Cu, Fe, and Zn were present in some samples. K and Na showed uniform distributions throughout enamel and dentin. Alkaline and earth-alkaline metals showed significant positive correlations. Zinc and manganese exhibited differences in the dentin content based on the place of residence. Zinc also displayed statistically significant differences between smokers’ and nonsmokers’ dentin samples. The differences were more pronounced between intra groups (within one sample) than for inter groups (within different groups, such as location, gender, and smoking).
Abstract Simultaneous adsorption of heavy metals in complex multi metal system is insufficiently explored. This research gives results of key process parameters optimization for simultaneous removal of Cd(II), Co(II), Cr(III), Cu(II), Mn(II), Ni(II) and Pb(II) from aqueous solution (batch system). New lemon peel-based biomaterial was prepared and characterized by infrared spectroscopy with Fourier transformation (FTIR), scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS), while the quantification of metals was made by atomic absorption spectrometry (AAS). Simultaneous removal of seven metals ions was favorable at pH 5 with 300 mg/50 mL solid-liquid phase ratio, within 60 min at room temperature with total obtained adsorption capacity of 46.77 mg g−1. Kinetic modeling showed that pseudo-second order kinetic and Weber-Morris diffusion models best describe the adsorption mechanism of all seven heavy metals onto lemon peel.
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