1. Tuning the photocatalytic activity of nanocrystalline titania by phase composition control and nitrogen doping, using different sources of nitrogenNejc Rozman, Luka Škrlep, Miran Gaberšček, Andrijana Sever Škapin, 2014, original scientific article Abstract: Titania nanoparticles were synthesized by employing the hydrothermal method and using TiOSO4as a titanium source. By varying pH between 0.5 and 1.0 and adding isopropanol to the hydrothermal reaction mixture, different mixtures of anatase, rutile, and brookite were obtained. The samples were also doped with nitrogen at different N concentrations using, respectively, urea, ammonium nitrate, and tripropylamine as nitrogen sources. The samples were characterized by X-ray powder diffraction, field emission scanning electron microscopy, infrared spectroscopy, UV-Vis diffuse reflectance spectroscopy and according to their specific surface area. Additionally, their photocatalytic activity was measured in a gas-solid reactor system. The results show that low pH favours rutile formation, whereas a higher pH yields mixed phase titania polymorphs. Isopropanol addition also favours rutile formation, and boosted the photocatalytic activity of the resulted particles. Contrary to most data in the literature, rutile turned out to be the more active phase in the present investigation. Nitrogen doping, on the other hand, did not contribute to higher photocatalytic activity, but was rather detrimental to it.
Keywords: titanium dioxide, rutile, hydrothermal synthesis, photocatalysis, nitrogen doping
Published in DiRROS: 26.09.2025; Views: 257; Downloads: 100
 Full text (503,29 KB)
This document has many files! More... |
2. 19th conference of the european association for sociology of sport“Transitioning sport – transitioning european societies”, Budapest, Hungary 29 May–2 June 2023 : report on conferenceSaša Pišot, 2023, other component parts Keywords: sports, sociology of sports, doping, social media, conferences, reports
Published in DiRROS: 16.04.2024; Views: 934; Downloads: 541
Full text (199,97 KB)
This document has many files! More... |
3. Metabolic consequences of anabolic steroids, insulin, and growth hormone abuse in recreational bodybuilders : implications for the world anti-doping agency passportFilippo Giorgio Di Girolamo, Chiara Biasinutto, Alessandro Mangogna, Nicola Fiotti, Pierandrea Vinci, Rado Pišot, Filippo Mearelli, Boštjan Šimunič, Chiara Roni, Gianni Biolo, 2024, original scientific article Abstract: Background Hormonal doping in recreational sports is a public-health concern. The World Anti-Doping Agency (WADA) promoted the creation of the Athlete Biological Passport, aiming to monitor athlete’s biological variables over time to facilitate indirect detection of doping. Detection tests for anabolic androgenic steroids (AAS) and growth hormone (GH) are available while insulin abuse cannot be revealed. We have determined in recreational bodybuilders the metabolic effects associated with different patterns of hormone abuse. All analyses were conducted using Statistical Package for Social Sciences (SPSS) 21.0 software (SPSS Chicago, IL). Results We have assessed plasma concentrations of selected metabolic markers and fatty acid content in erythrocyte membranes of 92 male bodybuilders and in 45 healthy controls. Hormonal abuse was identified by anonymous questionnaires. 43% (%) of recruited bodybuilders regularly abused hormones, i.e., anabolic androgenic steroids (95%) often associated with GH (30%) and/or insulin (38%). HDL-cholesterol was lower in insulin and/or GH abusers. Alanine (ALT) and aspartic (AST) transaminases were greater in hormone abusing bodybuilders than in non-doping bodybuilders and controls. Insulin doping was selectively associated with increased plasma ALT-to-AST ratio. In erythrocyte membranes, elongase activity (i.e., stearic-to-palmitic ratio) was lower in insulin and/or growth hormone doping, whereas increased Δ-9 desaturase activity (i.e., palmitoleic-to-palmitic ratio) was selectively associated with insulin doping. Conclusions In conclusion, our study demonstrates that insulin and GH abuse are characterized by multiple alterations of specific metabolic markers. Although further studies are needed to test whether longitudinal monitoring of selected metabolic marker such as muscle contraction time, HDL levels, ALT-AST ratio as well as the activities of selected enzymes (e.g. Δ-9 desaturase and elongase), could contribute to the detection of insulin and GH abuse in sport.
Keywords: bodybuilders, doping, drug abuse, matabolism
Published in DiRROS: 03.04.2024; Views: 1219; Downloads: 507
Full text (1,38 MB)
This document has many files! More... |
4. Metal and non-metal modified titania : the effect of phase composition and surface area on photocatalytic activityBoštjan Žener, Lev Matoh, Martin Reli, Andrijana Sever Škapin, Romana Cerc Korošec, 2022, original scientific article Abstract: The application of TiO 2 photocatalysis in various environmental fields has been extensively studied in the last decades due to its ability to induce the degradation of adsorbed organic pollutants. In the present work, TiO 2 powders doped and co-doped with sulfur and nitrogen and modified with platinum were prepared by particulate sol-gel synthesis. PXRD measurements revealed that the replacement of HCl with H 2SO4 during synthesis reduced the size of the crystallites from ~ 30 nm to ~20 nm, increasing the surface area from ~44 m2/g to ~80 m2/g. This is consistent with the photocatalytic activity of the samples and the measured photocurrent behavior of the photocatalysts. The results showed that the prop- erties of the powders (i.e., surface area, crystallite size, photocurrent behavior) depend strongly not only on the type but also on the amount of acid and dopants used in the synthesis. Doping, co-doping and modification of TiO 2 samples with nitrogen, sulfur and platinum increased their photocatalytic activity up to 6 times.
Keywords: titanium dioxide, powders, doping, photocatalysis, photocurrent, SEM
Published in DiRROS: 04.05.2023; Views: 1336; Downloads: 699
Full text (1,00 MB)
This document has many files! More... |
5. |
6. |
7. |
