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Nanosized multi-doped ceria with composition Ce0.8Nd0.0025Sm0.0025Gd0.005Dy0.095Y0.095O2-δ (CNSGDY) as perspective solid ionic conductor was obtained by modified glycine-nitrate procedure (MGNP) and room temperature self-propagating reaction (SPRT). The pressed pellets of both powders were sintered at 1550°C for 2 h in an air atmosphere. The obtained sintered samples were characterized by XRPD, Raman spectroscopy, FESEM, EDS and EIS methods. Despite a high temperature of sintering, XRPD and FESEM analyses of the samples confirmed appropriate dimensions of grains with fluorite structure. Overall concentration of introduced dopants (x = 0.2) in the structure of CeO2 after the sintering process was confirmed by EDS analysis. After sintering, Raman spectroscopy confirmed retention of the oxygen vacancies in the ceria lattice, which is in accordance with the improvement of ionic conductivity of solid ionic conductors. The highest value of total conductivity was obtained for the sintered MGNP sample at 700°C (4.22 × 10−2 S cm−1), with the corresponding activation energy of 0.26 eV.

Analysis and measurement of the level of concentration of the banking market is a significant component of the efficient functioning of the economy, an indicator of the development of both the financial and real sectors and an indicator of the degree of competitiveness in the banking sector. This paper focuses on research and analysis of the level of concentration in the banking market of the Republic of Serbia. The main task and goal of this research is to analyze the level of concentration in the banking market of the Republic of Serbia through the prism of two indicators: the concentration ratio of the five largest banks (CR5) and Herfindahl-Hirschman concentration index (HHI), for the period from 2009 to 2019. The results of the research showed the absence of concentration (overall) in the domestic banking market, but also the existence of a trend (growth of market share of the five largest banks) which indicates that, in the future, there could be distortions of competition.

Every organization strives to achieve efficient business. In order to improve efficiency in one organization, various techniques, methods and tools are used in practice. One of these tools is the 5S tool, which enables the organization of the workplace in such a way so as to perform work in an efficient, effective and safe way. The application of a tool implies that a certain thing is placed in a certain place for easier identification when the time comes for its use. The 5S tool refers to 5 words derived from Japanese terminology that begin with the letter S, and which describe workplace practices that lead to visual control and lean production: seiri (sort), seiton (set in order), seiso (clean), seiketsu (standardize) and shitsuke (implement). The aim of this paper is to consider the application of the 5S tool in the banking sector of the Republic of Serbia, at the level of selected banking branches. The results of the research showed that the total average application of this tool in the analyzed branches is 48.6%.

The notion of a cashless society is slowly becoming an inevitability of the modern way of doing business. Withdrawal of cash from use is the result of wide application of information and communication technologies. Increasing digitalization has contributed to the fact that most transactions are performed via smart devices (phones, tablets, desktops), without the use of cash and without going to the bank. The development of technological innovations, as well as innovations in finance, has undoubtedly contributed to increasing efficiency in business, but the question is whether the increasing digitalization of life and business, which is reflected in the creation of a cashless society, is still so desirable for humanity. The paper focuses on the socio-economic aspects of withdrawing cash from use. On the one hand, states are given the opportunity to influence economic activities even more directly through their central banks, while on the other hand, the issue is raised concerning human freedoms and rights in the digital world, in which it will be possible to electronically control the entire business.

Alumina/YAG composites (AYX_t) with high relative density (99.2 %TD) were successfully obtained by mixing commercial alumina powder with different volume fractions of yttrium aluminium garnet (Y3Al5O12-YAG; 7, 14, 21 and 28). YAG was synthetized by nitrate glycine reaction in the form of precursor powder. Polycrystalline YAG powder was obtained by calcination at 950°C for 2 h. Additionally, obtained compositions were characterized by XRD, SEM, EDX and electrochemical impedance spectroscopy. By XRPD analysis was found that the particle size of YAG powders lies in the nanometric range (being lower than 35 nm). By SEM microphotographs of composites were confirmed the formation of a conductive path consisting from mutually interconnected YAG particles. This was confirmed by the electrochemical impedance spectroscopy. The highest electrical conductivity of grain (κg) and grain boundary (κgb) at 700ºC amounted to 2.22×10-2 Ω-1cm-1and 9.44×10-3 Ω-1cm-1, respectively, was measured in the composite containing 21 vol% of YAG.

Modified solution precipitation method was used to prepare pure and doped Mg, Sr and Na hydroxyapatite type materials (CaP, CaMgP and CaSrNaP). Modification consisted of partial substitution of nitrates by acetate solution in order to achieve a more soluble and cost effective synthesis. The obtained samples were calcined at 400ºC (CaP400, CaMgP400 and CaSrNaP400). All powders were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Calcined samples were densified at 1000ºC in an air for 3 h (CaP1000, CaMgP1000 and CaSrNaP1000). Sintered samples were characterized by XRPD, FTIR, SEM, EDS and complex impedance methods. The highest conductivity was found for the multi-doped phosphate sample (CaSrNaP1000) at 700ºC (1.90×10-3Ω-1cm-1). The corresponding activation energies of conductivity amounted to 0.31 eV in the temperature range 500-700ºC. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III, Grant no. 45012 and Grant no. OI 176016]

In presented paper, influence of temperature, precursor concentration and different hydroxides on properties of activated carbon obtained from saccharose were investigated. The samples were prepared by hydrothermal treatment and activated using KOH, NaOH and LiOH. Two saccharose concentrations (0.5, 1.0 mol/dm3) and three temperatures (160, 200, 240 ºC) were changed in hydrothermal treatment. Activation processes were performed at 750ºC under N2 atmosphere. Samples were characterized by X-ray powder diffractometry, elemental analysis, N2 adsorption-desorption measurements, Fourier-transform infrared spectrometry, scanning electron microscopy and thermal analysis. The obtained samples were tested for potential application in dyes removal from water solutions. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45005, Grant no. III45012 and Grant no. TR34013]

In presented paper influence of the underground mining waste on the environmental was investigated. From that point tailings and wastewater characterization was performed on samples taken from lead and zinc mine Grot, Serbia. In order to obtain experiments necessary for characterization, representative samples were taken from three different parts of the tailings: outlet pipe of the flotation facility (JOF), hydro cyclone overflow (JHC) and crest of dam (JKB). Characterization of the tailing samples include: thermal (differential thermal analysis and thermo gravimetric analysis (DTA/TGA) and infrared analysis (FTIR), determination of the chemical composition and content of the heavy metals and qualitative roentgen analysis (XRPD). Also, wastewater samples have been taken from the tailings and concentrations of heavy metals in the taken samples were determined by using inductively coupled plasma mass spectrometry (ICPMS).

Single-molecule nanopore detection technology has revolutionized proteomics research by enabling highly sensitive and label-free detection of individual proteins. Herein, we designed a small, portable, and leak-free flowcell made of PMMA for nanopore experiments. In addition, we developed an in situ functionalizing PLL-g-PEG approach to produce non-sticky nanopores for measuring the volume of diseases-relevant biomarker, such as the Alpha-1 antitrypsin (AAT) protein. The in situ functionalization method allows continuous monitoring, ensuring adequate functionalization, which can be directly used for translocation experiments. The functionalized nanopores exhibit improved characteristics, including an increased nanopore lifetime and enhanced translocation events of the AAT proteins. Furthermore, we demonstrated the reduction in the translocation event's dwell time, along with an increase in current blockade amplitudes and translocation numbers under different voltage stimuli. The study also successfully measures the single AAT protein volume (253 nm 3 ), which closely aligns with the previously reported hydrodynamic volume. The real-time in situ PLL-g-PEG functionalizing method and the developed nanopore flowcell hold great promise for various nanopores applications involving non-sticky single-molecule characterization., (© 2023 The Authors. Chemistry - An Asian Journal published by Wiley-VCH GmbH.)

During the last two years, the COVID-19 pandemic continues to wreak havoc in many areas of the world, as the infection spreads through person-to-person contact. Transmission and prognosis, once infected, are potentially influenced by many factors, including indoor air pollution. Particulate Matter (PM) is a complex mixture of solid and/or liquid particles suspended in the air that can vary in size, shape, and composition and recent scientific work correlate this index with a considerable risk of COVID-19 infections. Early Warning Systems (EWS) and the Internet of Things (IoT) have given rise to the development of Low Power Wide Area Networks (LPWAN) based on sensors, which measure PM levels and monitor In-door Air pollution Quality (IAQ) in real-time. This article proposes an open-source platform architecture and presents the development of a Long Range (LoRa) based sensor network for IAQ and PM measurement. A few air quality sensors were tested, a network platform was implemented after simulating setup topologies, emphasizing feasible low-cost open platform architecture.

Realization of navigation in virtual environments remains a challenge as it involves complex operating conditions. Decomposition of such complexity is attainable by fusion of sensors and machine learning techniques. Identifying the right combination of sensory information and the appropriate machine learning technique is a vital ingredient for translating physical actions to virtual movements. The contributions of our work include: (i) Synchronization of actions and movements using suitable multiple sensor units, and (ii) selection of the significant features and an appropriate algorithm to process them. This work proposes an innovative approach that allows users to move in virtual environments by simply moving their legs towards the desired direction. The necessary hardware includes only a smartphone that is strapped to the subjects' lower leg. Data from the gyroscope, accelerometer and campus sensors of the mobile device are transmitted to a PC where the movement is accurately identified using a combination of machine learning techniques. Once the desired movement is identified, the movement of the virtual avatar in the virtual environment is realized. After pre-processing the sensor data using the box plot outliers approach, it is observed that Artificial Neural Networks provided the highest movement identification accuracy of 84.2% on the training dataset and 84.1% on testing dataset.