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Silver powders produced by both electrochemical (galvanostatic (DC) and potentiostatic (POT) regimes of electrolysis) and chemical processes were examined by scanning electron microscope, and particle size distribution (PSD) of the obtained particles was done. In the DC regime, the current densities of –14.4 mA cm-2 for the nitrate (NIT; powder denoted with DC(NIT)) and –13.05 mA cm-2 for the ammonium (AM; DC(AM)) electrolytes were applied. In the POT regime, the used overpotentials were –90 mV (NIT(90)) and –150 mV (NIT(150)) for the nitrate, and –625 mV (AM(625)) and –925 mV (AM(925)) for the ammonium electrolytes. Reduction with hydrazine was used for chemical synthesis (powder denoted with HYD). On the basis of SEM and PSD analysis, Ag powders were grouped into three groups. In the first group DC(AM), AM(925) and HYD powders with the (8.4–8.9 %) volume ratios were placed. In the second group were AM(625) and DC(NIT) powders with the (6.5–6.6 %) volume ratios. NIT(90) and NIT(150) powders with the volume ratios of (5.2–5.7 %) made the third group. The obtained volume ratios were correlated with the morphology of synthesized particles in order to perceive advantages and lacks of powder production via electrochemical and chemical routes.

Omega-3 fatty acid interventions show potential benefits in Alzheimer’s disease (AD) when initiated during its early stages. This study investigated whether maternal diet supplemented with omega-3-rich fish oil (FO) could delay or reduce amyloid beta (Aβ) formation, a key feature of AD, in 5xFAD transgenic offspring. Dams received FO during mating, pregnancy, and lactation. Brain tissues from female offspring were collected at 2 and 6 months of age. The findings indicated a shift in amyloid precursor protein processing, evidenced by increased soluble amyloid precursor protein α (sAPPα) levels, suggesting a transition from amyloidogenic to non-amyloidogenic pathway. FO influenced the expression of presenilin 1 and 2 but did not impact Aβ levels in 2-month-old mice. However, FO reduced the Aβ burden in the brains of 6-month-old animals. Lipidomic analysis revealed that 5xFAD mice have unimpaired omega-3 acquisition during gestation and lactation in comparison to non-transgenic littermates. However, a response to FO supplementation was found in non-transgenic offspring only, indicating that alterations in brain lipids are not the primary mechanism of FO-induced Aβ decline in 5xFAD. In conclusion, FO did not prevent or delay amyloid pathology in genetically predisposed animals but did mitigate its progression, suggesting mechanisms that warrant further investigation.

The importance of salt in human and animal diets suggests that the local resources of saline soils, watercourses, and marshes with saline water had to be well known to past populations. Based on the analysis of the environs of a large number of Late Neolithic and Early Eneolithic sites, this research assumes the great importance of such resources. This paper examines the spatial relationships between settlements and these resources, in the example of five Late Neolithic settlements from the territories of the Pannonian Plain and the Central Balkans. The goals of the research are to provide an initial step in the reconstruction of potential locations for salt exploitation, and provide a better understanding of each settlement and, subsequently, its role and function in the local Neolithic settlement system. The research considers previously published results of the pedological analysis of the settlement environments and archaeological investigations of the settlements. If certain micro-regions and regions did not provide possibilities for the extraction of salt for both animal and human utilisation, salt, and probably cattle, had to be procured through exchange networks. However, if livestock could not be grazed in areas abundant in salt, then salt would have to be added to the animals’ diet. We conclude that Late Neolithic settlements should not be observed in isolation, but rather аs parts of wider settlement systems including exchange networks with salt as a major commodity. This represents one of the crucial factors for the understanding of cultural development during the 5th millennium BC.

Implementation of the quality management system (QMS) in organizations is directly linked to the performances and business activity relative to a competition. With increasing market competition and changing markets, the quality system becomes a significant component and is increasingly being researched and identified as a major factor in cooperative advantage over competition, stakeholder satisfaction and maintaining the good customer relationships in almost all organizations connected with metallurgy. This paper implements a multi-criteria approach to a decision-making based on the Analytic Hierarchy Process. The aim of this paper is to illustrate the assessment of benefits of the quality system implementation ranking the criteria for a sustainable development by the MCDM models.

The main aim of this research study was to determine the influence of 6 predictor variables, related to split times at every 100m of 400m race as well as of first and last 200m of 400m race, on criterion variable - final result in 400m event. Entity sample included 32 results from 26 female athletes who were participants of final 400m races at four World Championships in Athletics: Stuttgart (1993), Athens (1997), Seville (1999) and Berlin (2009). Data needed for this research study were obtained from official results and published biomechanical analyses. Multiple regression analysis revealed very high influence of predictor variables on criterion variable, that is – on final 400m result, with 99% of shared variance at the p level of 0.01. Observation of partial coefficients and split times at every 100m showed the best correlation to final result was split running time from 300th to 400thm, as well as running time of both 200m segments of 400m race, especially the second 200m. It can be concluded that all predictor variables are significant for successful placement in 400m race, which proves that even though 400m event is a sprint event, it still requires from runners highly developed abilities such as speed, speed endurance, strength, technique and tactics, mental stability and motivation to fight one self and other competitors in final segments of the race which places 400m event among the most demanding athletic events

The main goal of this work is to identify and analyze the impact of the Chinese economy key determinants on the global market copper price movements. Our research is based on a multilinear regression analysis of the historical data of the time period from 2003 until 2017. The presented multilinear regression model constitutes the 4 (four) statistically most significant macroeconomic variables, that is, determinants of the Chinese economy, which are used for clarifying current trends and can predict the future movements of prices on the global copper market. Statistically significant determinants are the inflation in China, the Chinese export of goods and services, Chinese import of copper, and consumption of refined copper in China. Obtained results of the research show a dominant role of the demand factor and significant influence of the Chinese economy on the movements of the global copper price. At the same time, the results imply that movements of the copper price on the global market can be an indicator of the economic activities slowing down or speeding up, in the countries which are the major traders of this metal.

The paper presents the results of research on the regional distribution and geographic setting of the 5th millennium BCE settlements in the Central Balkans. The research encompasses two successive archaeological cultures in the area between the Danube Valley and the upper course of the Južna Morava River and compares the regional distribution of the settlements and their topographic and pedological aspects. It has been concluded that the relocation occured on a regional level, meaning the abandonment or a reduced population of the regions which were densely populated during the Vinča culture. The emphasised dichotomy in the topographic type of the settlements with more or less equally distributed settlements compared to the altitude and an increased focus on soils unsuitable for cultivation suggest the utilisation of a wider range of local resources and a greater degree of mutual connections between the BSK settlements. The observed trends are interpreted in correlation with the previous knowledge on economic strategies of the population of the Central Balkans. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. OI 177020: Archaeology of Serbia: Cultural identity, integration factors, technological processes and the role of the Central Balkans in the development of European prehistory]

The subject of this paper are urban innovations that emerged from the Belgrade Master Plan, adopted by the Belgrade Assembly in September 2003. Twelve new spatial solutions that were directly related to the overall goals of the plan are presented. These are proposals for grand city projects created in 2001-2003 during the development of the Master Plan, which did not exist in the earlier master plans from 1951, 1972, and 1985, and their revisions. These projects were a response to the difficult economic, social, and urban situation of Belgrade in the aftermath of the breakup of Yugoslavia. They relate to the city region, the Confluence, the Danube orientation of Belgrade, the greenery system, the lasting values of the city, spontaneously constructed settlements, cultural assets, city centres, business and industrial zones and environment, social housing, transport, and modern architecture. Urban planners of different profiles who wrote this article were also engaged in the formulation of the Master Plan and are well acquainted with it. In the analysis, the authors relied on a formal document published in the Official Gazette of the City of Belgrade, and a CD-ROM containing the official maps of the Master Plan. For each project, its definition, the motive for the creation and its urban solution are given. An analysis of urban innovation has given a new understanding of Belgrade's intention to thoroughly improve the city and open up new ways of development, after the tragic 1990s, while safeguarding its identity based on features that differentiate it from other European metropolises and making it as self-contained cities.

Underground mining method selection is a very complex task for the mining engineers because the chosen method should fulfill the technical, economic and production requirements. Combining the criteria that cover different aspects of the mining operation and group decision-making increases the reliability of the decisions and minimize its subjectivity. The main objective of this paper is to propose the methodology for the underground mining method selection based on the Extended Pivot Pairwise Relative Criteria Importance Assessment (PIPRECIA-E) and group decision making. The applicability of the proposed methodology is demonstrated by using the numerical example inclusive of 3 main criteria, 18 sub-criteria and 5 alternative underground mining methods pointed to the exploitation of the Upper Zone of the Čukaru Peki deposit in Serbia.

The technogenic copper deposit of slag Depo 1 is located in the industrial district of the Smelter and Refineries of RTB Bor. Exploitation reserves are 9 190 940 t of slag with the average copper content of 0.715%. Sample of this deposit was melted in a furnace and then cooled with a jet of water when it was poured into a thin jet, whereby the small - granulated pieces were formed. Comparison of some properties of this sample was done with the sample in the form in which it was deposited in the deposit. This paper presents the chemical analysis, SEM - EDS analysis, Bond working index in a rod and ball mill, grinding kinetics and experiments of flotation concentration of copper depending on the grinding fineness in the range of 60 - 95% - 0.075 mm.

The purpose of the flotation process control is optimization the concentrate grade and recovery, while maximizing profits. Consequently, the research into modeling and control of this process has always been an important area in control engineering practice. This paper presents the results of development and validation the predictive models, based on the ANFIS hybrid system. Models predict the values of copper concentrate and tailings grade as well as copper recovery in the flotation plant 'Veliki Krivelj'. The copper content in the feed ore, collector consumption in the rough flotation stage and consumption of frother, were selected as the independent variables. Other technical and technological parameters, relevant for the process of flotation concentration were considered constant. The results of the models validation have showed that the models provide the good predictions of changes in the copper concentrate grade, while the predictions of changes in the copper recovery and tailings grade are somewhat poorer.

In terms of modern business practice, business prediction results are crucially important for evaluation of future financial performance of a company. Planning and prediction procedures are especially important for companies operating under uncertainty. This paper shows an example of planning and prediction of business results in insurance when calculating premium trend by use of linear and nonlinear regression. Due to the uncertainty associated with the moment of claim occurrence and claim amount, it is necessary to secure enough assets to cover the risks. Asset-liability matching requires the prediction of future premium movement per insurance lines which represents the basic concept of development and operation of insurance companies.

The selection of the most suitable flotation reagents is very important in the froth flotation process because the recovery of valuable minerals largely depends on the reagent regime. On the other hand, the particular characteristics of the ore excavated from different mine sites have their own specificity that should be taken into account in choosing the most appropriate reagents. Therefore, a proposal for forming a framework for selecting the most suitable flotation reagents is discussed in this paper. The usability and efficiency of the proposed approach are considered on the conducted empirical example.

Process approach is the basic element for integration the all similar requirements of the integrated management system (ISM) standard and stakeholders. Previous studies have shown that the process model of the ISM is the most represented in the Serbian companies. Implementation of the process model in mining company improves the company performances. This work analyzes the most important advantages achieved in implementation the process model and the appropriate criteria are defined for their evaluation. The AHP method was used to evaluate the advantages of process model. The results differentiate the most important advantages of the process model achieved by sustainable business operations of mining companies on the basis of competitiveness based on eco-innovations.

The residual service life of the components of power plants under conditions of creep can be measured by various methods. As a rule, these methods can be classified as destructive, nondestructive, or analytical. The nondestructive method is based on the determination of the metallographic A-parameter, i.e., a quantity equal to the ratio of the number of damaged grain boundaries to the total number of boundaries in the direction of the principal normal stress. By using this method, we determine the residual service life of a pipeline bend operating at a temperature of 530°C under a stress of 100 MPa. [ABSTRACT FROM AUTHOR]

A longitudinal crack appeared in a straight segment of a steam pipeline of an intermediate superheater after operating for 90,000h. The pipeline of 14MoV63 steel with dimensions 609 × 25 mm operated at a temperature of 540°C under a pressure of 18 MPa. We found that its failure is mainly explained by creep. To establish the causes of creep in the straight segment of the steam pipeline, whose predicted service life was 100,000h, we determined the mechanical characteristics of the material and studied its microstructure and fracture surfaces. [ABSTRACT FROM AUTHOR]

A sample of slag from the Flotation Bor, RTB Bor, was mineralogical tested after granulation in the laboratory conditions. Minerals contained in the sample of granulated slag are: fayalite and ferrite that form the basis with rarely sprayed fine particles of magnetite, pyrite, chalcopyrite, bornite, copper matte and elemental - native copper [6, 7]. Granulation of slag was conducted in the laboratory conditions on the device specially designed for this purpose.