Stability of 3D black hole with torsion

Using $N=1+1$ supersymmetric extension of the three-dimensional gravity with torsion, we show that a generic black hole has no exact supersymmetries, the extremal black hole has only one, while the zero-energy black hole has two. Combining these results with the asymptotic supersymmetry algebra, we are naturally led to interpret the zero-energy black hole as the ground state of the Ramond sector, and analogously, the anti-de Sitter solution as the ground state of the Neveau-Schwartz sector.Comment: LATEX, 9 page

Self-dual Maxwell field in 3D gravity with torsion

We study the system of self-dual Maxwell field coupled to 3D gravity with torsion, with Maxwell field modified by a topological mass term. General structure of the field equations reveals a new, dynamical role of the classical central charges, and gives a simple correspondence between self-dual solutions with torsion and their Riemannian counterparts. We construct two exact self-dual solutions, corresponding to the sectors with massless and massive Maxwell field, and calculate their conserved charges.Comment: LATEX, 15 pages, v2: minor correction

Fixed point theorems of Perov type

In this dissertation is introduced a new class of contractions in the setting of cone metric space, both solid and normal, by including an operator as a contractive constant. Some wellknown fixed point theorems are improved and obtained results generalize, Banach, Perov, Ćirić and Fisher theorem, among others. Common fixed point problem for a pair or a sequence of mappings is studied from a different point of view. Wide range of applications is corroborated with numerous examples

Spectral Analysis of Protein-Protein Interactions in Drosophila melanogaster

Within a case study on the protein-protein interaction network (PIN) of Drosophila melanogaster we investigate the relation between the network's spectral properties and its structural features such as the prevalence of specific subgraphs or duplicate nodes as a result of its evolutionary history. The discrete part of the spectral density shows fingerprints of the PIN's topological features including a preference for loop structures. Duplicate nodes are another prominent feature of PINs and we discuss their representation in the PIN's spectrum as well as their biological implications.Comment: 9 pages RevTeX including 8 figure

On Drazin inverse of operator matrices

AbstractIn this short paper, we offer (another) formula for the Drazin inverse of an operator matrix for which certain products of the entries vanish. We also give formula for the Drazin inverse of the sum of two operators under special conditions

Additive results for the generalized Drazin inverse in a Banach algebra

AbstractIn this paper we investigate additive properties of the generalized Drazin inverse in a Banach algebra. We find some new conditions under which the generalized Drazin inverse of the sum a+b could be explicitly expressed in terms of a, ad, b, bd. Also, some recent results of Castro and Koliha [New additive results for the g-Drazin inverse, Proc. Roy. Soc. Edinburgh Sect. A 134 (2004) 1085–1097] are extended

Electric field in 3D gravity with torsion

It is shown that in static and spherically symmetric configurations of the system of Maxwell field coupled to 3D gravity with torsion, at least one of the Maxwell field components has to vanish. Restricting our attention to the electric sector of the theory, we find an interesting exact solution, corresponding to the azimuthal electric field. Its geometric structure is to a large extent influenced by the values of two different central charges, associated to the asymptotic AdS structure of spacetime.Comment: LATEX, 15 pages, v2: minor correction

Supplementary data for the article: Grbović, G.; Malev, O.; Dolenc, D.; Klobučar, R. S.; Cvetković, Z.; Cvetković, B.; Jovančicévić, B.; Trebše, P. Synthesis, Characterisation and Aquatic Ecotoxicity of the UV Filter Hexyl 2-(4-Diethylamino-2-Hydroxybenzoyl)Benzoate (DHHB) and Its Chlorinated by-Products. Environmental Chemistry 2016, 13 (1), 119–126. https://doi.org/10.1071/EN15013

Supplementary material for: [https://doi.org/10.1071/EN15013]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2020

Aluminium electrodeposition onto glassy carbon from deep eutectic system made of AlCl3+urea

Electrochemical deposition of aluminium onto glassy carbon from deep eutectic solvent (DES), made of the AlCl3+urea, at 25-50°C have been investigated. The deposition was performed in potentiostatic mode. The morphology of the obtained deposits were characterized using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Critical overpotential of aluminium deposition decreased from around – 0.150 V at 25°C to around – 0.100 V at 50°C. All recorded currents were small but would substantially increase with increasing working temperature (from 0.01 mA cm-2 up to 0.25 mA cm-2). The deposits obtained showed variety of morphological shapes depending on the working temperature and potential applied. All the deposits were made of very small crystallites grouped randomly into more or less separate agglomerates. Density of the crystallites distribution over the substrate and complicity of the crystal forms increased with the potential applied. Electrodeposition/dissolution of aluminium in used electrolyte onto used substrate obviously promises positive results if research aiming at reversible systems of such composition working at temperatures very close to room temperature.Ispitivano je elektrohemijsko taloženje aluminijuma na staklastom ugljeniku iz eutektičke smeše (DES), AlCl3+urea, na temperaturama od 25-50°C. Elektrotaloženje je izvođeno potenciostatski. Morfologija dobijenih taloga je analizirana skenirajućom elektronskom mikroskopijom (SEM) i energetsko disperzivnom spektroskopijom (EDS). Kritične prenapetosti elektrotaloženja aluminijuma kretale su se od oko – 0.150 V pri 25°C do oko – 0.100 V pri 50°C. Zabeležene gustine struje bile su male, ali su njihove vrednosti značajno rasle sa povećanjem radne temperature (od 0.01 mA cm-2 do 0.25 mA cm-2 uz povećanje temperature od 25°C do 50°C). Dobijeni talozi pokazali su raznovrsne morfološke oblike što je zavisilo od primenjene temperature i potencijala. Svi talozi sastojali su se od veoma malih kristala objedinjenih u aglomerate koji su bili nasumično raspoređeni po površini radne electrode. Gustina rasporeda kristalita po površini elektrode i njihova pojedinačna raznovrsnost po obliku rasle su sa povećanjem primenjenog potencijala. Elektrohemijsko taloženje/rastvaranje aluminijuma u upotrebljenom elektrolitu i na upotrebljenoj podlozi obećava pozitivne rezultate u istraživanjima usmerenim na reverzibilne sisteme istog ili sličnog sastava koji bi trebalo da rade na temperaturama veoma bliskim sobnoj

Study on a standard for grounding systems realization

Grounding systems of objects inside power facilities are very often realized as structures consisting of protective electrodes’ system placed in the object foundation, and neutral electrodes’ system placed at a specified distance from the object. Official standards and publications recommend a minimal value for the distance between the protective and the neutral part of grounding structures, so that the influence of one on another can be neglected. We analyze several practical implementations of grounding structures and demonstrate that the minimal distance is actually much smaller than that recommended by the standards