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  • Author: Rafał J. Wróbel x
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Abstract

Secondary activation of commercial activated carbon (AC) ORGANOSORB 10-CO was carried out at 600, 700 and 800oC with mass ratios of potassium to AC (K/AC) in range 1-3. Crucial samples have shown following CO2 uptakes and SSA - 3.90 mmol/g and 1225 m2/g, 4.54 mmol/g and 1546 m2/g, 4.28 and 1717 m2/g for pristine material and samples obtained at 700oC with K/AC = 2 and at 800oC with K/AC = 3 respectively. Last sample also indicated signifi cant mesopore volume increase in diameter range 2-5 nm, from 0.11 to 0.24 cm3/g. CO2 uptake increase was explained by formation of micropores up to diameter of 0.8 nm, which distribution was established from CO2 sorption using DFT. Surface chemistry of all samples has not changed during modifi cation, what was proven by XPS. Moreover, deeper incorporation of potassium ions into graphite at higher temperatures was observed as confi rmed with EDS, XPS and XRD.

Abstract

Dental anxiety is a very important factor affecting the efficacy of prevention, diagnosis and treatment of dental diseases, both in patients in the developmental age and in young adults. Anxiety is considered an emotional state with negative connotations. The aim of the study was to determine the level of dental anxiety in first year university students, the intent being to help to develop an individual treatment plan in this group of patients. The study involved 280 students including 230 females and 50 males. Of these, 122 patients were from the Medical University of Lublin, 79 from University of Life Sciences and 79 from University of Maria Curie-Skłodowska. The mean age of the study subjects was 21 years and 8 months ± 3,9 months. No differences in the level of dental anxiety between women and men were observed. The highest level of dental anxiety was observed among students of University of Life Sciences, while the lowest level was observed among students of the Medical University

Abstract

Superparamagnetic iron oxide nanoparticles were obtained in the polyethylene glycol environment. An effect of precipitation and drying temperatures on the size of the prepared nanoparticles was observed. Superparamagnetic iron oxide Fe3O4, around of 15 nm, was obtained at a precipitation temperature of 80°C and a drying temperature of 60°C. The presence of functional groups characteristic for a polyethylene glycol surfactant on the surface of nanoparticles was confirmed by FTIR and XPS measurements. Silver nanoparticles were introduced by the impregnation. Fe3O4-Ag nanostructure with bactericidal properties against Escherichia coli species was produced. Interesting magnetic properties of these materials may be helpful to separate the bactericidal agent from the solution.