Journal of Knot Theory and Its Ramifications
(World Scientific Publishing Co. Pte. Ltd.)
• 03 Jan 2019
Najdanović, Marija • Rančić, Svetozar • Kauffman, Louis • Velimirović, Ljubica
In this paper, we consider infinitesimal bending of the second-order of curves and
knots. The total curvature of the knot during the second-order infinitesimal bending is
discussed and expressions for the first and the second variation of the total curvature
are given. Some examples aimed to illustrate infinitesimal bending of knots are shown
using figures. Colors are used to illustrate curvature values at different points of bent
knots and the total curvature is numerically calculated.
Proceedings of the CODEMA 2020
(Union od Mathematicians of Macedonia – ARMAGANKA)
• 01 Apr 2024
Najdanović, Marija • Velimirović, Ljubica • Rančić, Svetozar
In this paper we point out the geometric aspect of knots. By the term
knot we mean a closed self-avoiding curve in a 3-dimensional Euclidean space.
We consider infinitesimal bending of knots and examine the behavior of torus
knots under this type of deformation.
The Secend International Conference on Sustainable Enviroment and Technologies, 23-24 September 2022, Belgrade, Serbia
• 01 Apr 2024
Laban, Bojana • Milenković, Mila • Petković, Branka
In this work, we present a review of the simple synthesis of iron(III)-oxide nanoparticles (Fe2O3 NPs), their characterization and potential application as nanosorbents and voltammetric sensors. Fe2O3 NPs were obtained from Fe2+ and Fe3+ salts by the solid-state method and characterized by transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Ultraviolet-visible spectroscopy (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR). The morphology and average size of Fe ...
57th meeting of the Serbian Chemical Society, Kragujevac, Serbia, June 18/19, 2021
• 01 Apr 2024
Pantović, Tijana • Jovanović, Filip • Petković, Branka • Laban, Bojana
Nanočestice metala i oksida metala (NPs) privlače pažnju mnogih istraživača zbog svojih jedinstvenih optičkih i električnih svojstva. Ove nanočestice nalaze primenu u biologiji, medicini, kao i u elektronici, za izradu senzora. U ovom radu sintetisane su nanočestice srebra (Ag NPs) i gvožđe(III)-oksida (Fe2O3 NPs), jednostavnom „solid-state“ metodom iz čvrstog stanja uz prisustvo različitih soli kao stabilizatora. Sintetisane su Ag i Fe2O3 NPs uz trinatrijum citrat kao stabilizator, kao i Fe2O3 ...
8th SYMPOSIUM Chemistry and Enviromental Protection, 30.05.-01.06. 2018. Kruševac, Serbia
• 01 Apr 2024
Jevtić, Sonja • Vukojević, Vesna • Đurdjić, Slađana • Pergal, Marija • Manojlović, Dragan • Petković, Branka • Stanković, Dalibor
Pethoxamid (РОА) is relatively new herbicide and it belongs to group of chloroacetamides. lt inhibits the germination of target weeds in com, soybeans, peas and beans, tobacco and other crops and it can affects on herbicide-resistant weeds. There are no many research records about this, in the future quite applicable, herbicide. Bearing in mind that pethoxamid is high soluble in water, with almost no sorption in soils [1], the leaching and runoff of this compound in ground and surfac ...
8th SYMPOSIUM Chemistry and Enviromental Protection, 30.05.-01.06. 2018. Kruševac, Serbia
• 01 Apr 2024
Jovanović, Vojislav • Samaržija-Jovanović, Suzana • Jevtić, Sonja • Petković, Branka • Marković, Gordana • Marinović-Cincović, Milena
Zbog emisije formaldehida (СН2О) iz drvenih proizvoda, gde se urea- formaldehidne (UF) smole, izmedu ostalog, koriste za impregnaciju drvenih panela koje se koriste u unutrasnjosti stambenih i drugih objekata pozeljno је da procenat slobodnog formaldehida (СН2О) u samoj smoli bude sto manji, jer је poznato da formaldehid ima stetno dejstvo na coveka, odnosno сео zivi svet. Pare formaldehida jako nadrazuju disajne puteve. Koncentracije od 10-20 ppm otezavaju disanje, а konc ...
56th meeting of the Serbian Chemical Society, Niš, Serbia, June 7/8, 2019
• 01 Apr 2024
Laban, Bojana • Veljović, Đorđe • Petković, Branka • Jokić, Anja
Nanočestice plemenitih metala (NPs) od velikog su interesa zbog svojih izvanrednih optičkih, hemijskih i fizičkih svojstava1. Nanočestice srebra (Ag NPs) privukle su posebnu pažnju zbog njihove primene u različitim oblastima. Ag NPs čestice najčešće se dobijaju redukcijom jona Ag+ u vodenim rastvorima. Međutim, koloidne disprezije su stabilne samo pri niskim koncentracijama metala i teško je dobiti prah NPs iz njihovih disperzija. U literaturi je objavljena sinteza praha Ag NPs primenom skroba m ...
56th meeting of the Serbian Chemical Society, Niš, Serbia, June 7/8, 2019
• 01 Apr 2024
Savić, Nada • Glišić, Biljana • Petković, Branka • Wadepohl, Hubert • Vojnović, Sandra • Nikodinović-Runić, Jasmina • Djuran, Miloš
U ovom radu, N,N',N'',N'''-tetrakis(2-piridilmetil)-1,4,8,11-tetraazaciklotetradekan (tpmc) kao makrociklicni ligand sa 2-piridilmetil grupama je korišćen za sintezu kompleksa srebra(I). Različite AgX soli (X = CF3SO3-, CF3COO- i BF4-) su korišćene za sintezu u cilju ispitivanja uticaja kontra-anjona na nuklearnost, stabilnost i biološku aktivnost kompleksa. Sintetisani kompleksi srebra(I) su okarakterisani primenom različitih spektroskopskih metoda, ciklične voltametrije i rendgenske strukturne ...
56th meeting of the Serbian Chemical Society, Niš, Serbia, June 7/8, 2019
• 01 Apr 2024
Milenković, Mila • Jevtić, Sonja • Laban, Bojana • Petković, Branka • Jokić, Anja
Nanočestice na bazi oksida gvožđa (NPs) su privukle veliku pažnju imajući u vidu njihove fizičke, posebno magnetne, i hemijske osobine. U ovom istraživanju su nanočestice gvožđe(III)-oksida (Fe2O3 NPs) sintetisane jednostavnim hemijskim metodom u čvstom stanju iz dve različite soli, FeSO4 . 7H2O i FeCl3 . H2O, u molskom udelu (1 : 2,5). Veličina NPs od 3 nm i njihov sferni oblik su određeni TEM merenjima. Dobijene NPs su dispergovane u vodi i monodisperzni koloid je okarakterisan UV-Vis i FTIR s ...
Twenty-first YUCOMAT 2019 & Eleventh WRTCS 2019, Herceg Novi, September 2 - 6, 2019
• 01 Apr 2024
Petković, Branka • Stanković, Dalibor • Ognjanović, Miloš • Viktorovich Avdin, Vyacheslav • Radović, Magdalena • Manojlović, Dragan • Vranješ Đurić, Sanja
The novel carbon material modified with Co3O4 particles, prepared by calcination and mixed with single wall carbon nanotubes, was characterized and used for sensing of prominent antioxidant α- lipoic acid (LA). The new material was prepared by thermolysis of Novolac phenol-formaldehyde resin and cobalt(III) nitrate mixed with graphite powder, producing mostly glassy carbon decorated with cobalt oxide. XRD and SEM measurements were used to study composition, structure and morphology of cobalt oxi ...
