T. Pavlovic, I. Radonjić, D. Mirjanić, Darko Divnić
{"title":"LEGAL REGULATIONS FOR THE USE OF RENEWABLE SOURCES OF ENERGY IN SERBIA AND THE REPUBLIC OF SRPSKA","authors":"T. Pavlovic, I. Radonjić, D. Mirjanić, Darko Divnić","doi":"10.7251/comen2102253p","DOIUrl":"https://doi.org/10.7251/comen2102253p","url":null,"abstract":"The paper provides information on renewable energy sources (RES) and legislation related to the RES generated electricity in Serbia and the Republic of Srpska. In Serbia, hydropower, wind energy, solar energy, biomass and biogas are used for the RES generated electricity, whereas hydropower, solar energy, biomass and biogas are utilized in the Republic of Srpska. The paper gives an overview of the power of RES power plants and the percentage share of the thermal power plants and RES power plants in electricity production and the guaranteed (incentive) prices for RES generated electricity in Serbia and the Republic of Srpska. Furthermore, legal regulations related to the production of electricity from RES in Serbia and the Republic of Srpska are given. In the conclusion, it is pointed out that RES is increasingly used in Serbia and the Republic of Srpska for the production of electricity, that there are appropriate legal regulations and guarantees (incentive prices) for electricity generated by RES power plants.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89884971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"SUSTAINABLE TRANSBOUNDARY HYDROPOWER SYSTEM ON DRINA RIVER AS SYNERGY OF WATER -FOOD-ENERGY-CLIMATE NEXUS","authors":"S. Stevović","doi":"10.7251/comen2102184s","DOIUrl":"https://doi.org/10.7251/comen2102184s","url":null,"abstract":"The Drina River has always been a source of drinking water and irrigation for food production, with all its tributaries and branching catchment area across the territories of Bosnia and Herzegovina, Montenegro and Serbia. It has connected peoples and cultures for centuries with its bridges. At the same time, with its great head, the Drina has always represented a significant hydropower potential. Throughout history, numerous watermills have been built on it. Currently, there are several constructed hydro-technical facilities on the Drina and in its catchment area. Among them, the most important are dams, with roads over them, associated hydroelectric power plants and belonging structures for flood control, water intakes for drinking water or irrigation. Due to multiple possible, almost always conflicting purposes, as well as several states, entities and other stakeholders, the management of Drina River water resources from the angle of the water-food-energy and climate nexus is an extremely complex problem. In addition to the impact on hydropower, agriculture, forestry, transport, irrigation and drainage, tourism and socio-cultural events, the construction of such strategic structures has also an impact on the climate of the Western Balkans. The issue of optimization within the nexus of the water-food-energy-climate requires holistic research to find synergistic solutions. These solutions are certainly a compromise. But inevitably, they must meet the criteria of sustainable development and the requirements of reducing global warming, according to the set conditions of the adopted European Green Plan for the Western Balkans. This paper proposes a methodology for finding optimal/compromise hydropower solutions, which synergistically include all parameters of influence. Holistic research of sustainable hydropower systems on the Drina River, from the angle of the water-food-energyclimate nexus, is presented. Particularly detailed analyses of the course of the river between the towns of Foča and Goražde, as well as the downstream part between Zvornik and mouth, known as the Lower Drina. In these sections, the most pronounced conflict is whether water will be used for drinking and/or food production and/or energy production and what impact possible solutions have on the climate of the region.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"89 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72793081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"THE EFFECT OF METHYL METHACRYLATE ON THE PROPERTIES OF SYNTHESIZED ACRYLATE EMULSIONS","authors":"Sonja Popić, I. Ristić, V. Mićić, Jelena Tanasić","doi":"10.7251/comen2101071p","DOIUrl":"https://doi.org/10.7251/comen2101071p","url":null,"abstract":"The effect of methyl methacrylate (MMA) addition on the properties of synthesized acrylate emulsions based on butyl acrylate (BA) and 2-ethylhexyl acrylate (EHA) was investigated. The samples were synthesized by addition of MMA in copolymer structure, ranging from 10 to 50 wt% of the total mass of BA and EHA. Fourier transformation infrared (FTIR) spectroscopy was used to analyze the molecular structure of synthesized acrylate emulsions and the results confirmed that a quantitative polymerization reaction occurred. The analysis of thermal properties showed that the addition of methyl methacrylate increases the glass transition temperature of the acrylate films obtained by drying the synthesized emulsions. The tensile strength and elongation at break increased proportionally with the increase of the content of MMA in the synthesized samples. Since the obtained acrylate materials can be used to improve the water impermeability of paper and other materials, the obtained emulsion was applied in a thin layer on a sheet of paper and the resistance of the paper to water and oil was investigated. The results showed that all emulsions were impermeable both to water and oil.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85077332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Grujić, B. Škipina, D. Cerovic, L. Topalić-Trivunović, A. Savić
{"title":"ANTIBACTERIAL AND DIELECTRIC PROPERTIES OF TEXTILE MATERIALS MODIFIED WITH HERBAL EXTRACT OF Picea omorika AND THE COPPER FERRITE NANOPARTICLES","authors":"D. Grujić, B. Škipina, D. Cerovic, L. Topalić-Trivunović, A. Savić","doi":"10.7251/comen2101080g","DOIUrl":"https://doi.org/10.7251/comen2101080g","url":null,"abstract":"In this paper, cotton, polyester and cotton/polyester fabrics were modified by using herbal extract of Picea omorika and copper ferrite nanoparticles and their antibacterial and dielectric properties were investigated. Antibacterial activities of all samples were examined against Escherichia coli and Staphylococcus aureus. Most of the fabrics modified by copper ferrite showed antibacterial activities against Escherichia coli, while the addition of the herbal extract improved their antibacterial protection. Dielectric properties were measured in frequency range from 24 Hz to 75 kHz at room temperature and the results showed that the modification of all three fabrics with copper ferrite caused increase in their electrical conductivity. The obtained results point to the possibility of using investigated fabrics for antibacterial protection as well as for the electromagnetic shielding application.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77220451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Savić, Gordana Broćeta, M. Aškrabić, Sonja Panić, Ljubomir Vidanović
{"title":"EFFECT OF MIXING APPROACH ON THE PROPERTIES OF CONCRETE WITH DIFFERENT AGGREGATE TYPES","authors":"A. Savić, Gordana Broćeta, M. Aškrabić, Sonja Panić, Ljubomir Vidanović","doi":"10.7251/comen2201074s","DOIUrl":"https://doi.org/10.7251/comen2201074s","url":null,"abstract":"The subject of the experimental tests presented in the paper is the influence of the mixing method on the physical and mechanical properties of fine-grained concrete with the nominally largest aggregate grain of 8 mm. Concretes with three different aggregate compositions (river, crushed and mixture with coarse recycled aggregate) were mixed using the usual approach, and then two-stage mixing approach (TSMA). Slump and flow, density and temperature were tested on fresh concrete. The compressive strength, flexural, splitting tensile strength, density, ultrasonic pulse velocity, and water absorption was recorded on hardened concrete. Concretes prepared using recycled aggregate, according to all the mentioned tests, can be used as an adequate replacement for concretes prepared using river or crushed aggregate, while the two-phase approach had the greatest effect on the increase of the splitting tensile strength.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91230533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"WOODEN STRUCTURES IN KENGO KUMA FACADES","authors":"Nikola Cekić","doi":"10.7251/comen2101099c","DOIUrl":"https://doi.org/10.7251/comen2101099c","url":null,"abstract":"Kengo Kuma (born 1954 in Kanagawa, Japan) is a Japanese architect and professor at the University of Tokyo. Realized a large number of urbarchitectonic structures worldwide, especially in the second decade of this century, emphasizing use of wooden materials in the facades. The examples of buildings in this paper demonstrate an extraordinary lucidity and opting of the designer for continuous use of the natural, environment-friendly material whose texture of wooden elements provides effective esthetic-composition and artisanal-artistic, attractive archisculptural results. The pronounced use of many times repeated timber elements created elegant latticework gigantic, harmonic façade network with new hand-made forms, without using bolts, nails or glue to join them. By using the easily available resource - wooden material, the famous architect’s end goal is „effacing” of the already seen architecture, i.e. façade of the new non-standardized and non-stereotypical structures of organically, imaginatively well integrated into the natural environment. Facades created by moving multiplied wooden elements, in a varied rhythm, along the vertical and horizontal lines, evoke a spatial narration, subtle visual sensations, whereby materiality and close rapport with the building tradition is of primary importance. In the paper, the attention is focused on the advanced ecourbarchitecture of “building with wooden material” using the contemporary computer technologies, with new designing artistic and visual approach to the culture of walls in the exterior.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87918403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"THE ROLE OF BATTERIES IN NEAR-FUTURE ENERGETICS","authors":"S. Mentus","doi":"10.7251/comen2101001m","DOIUrl":"https://doi.org/10.7251/comen2101001m","url":null,"abstract":"Since the first oil crisis in early 70-ties, the electrochemists strive to develop a chemical power source able to replace the liquid fossil fuels in traffic. Noticeable success was achieved in the decade 1980-1990. Thanks to a new class of materials – intercalate compounds, a new battery called lithium-ion battery was commercialized, having much higher energy density than its predecessors. In this work the origin of its high energy density is explained. The emergence of new battery supported effectively the expansion of use and the development of portable electronics - mobile phones, lap-top calculators tablets etc. Since 2010, connected to the global intentions to prevent climate changes, the batteries received the role of the energy sources of electric cars. Recently, connected to the rising use of renewable energy sources known to suffer of changeable intensity, batteries take also the role of grid energy storage, having the function to smooth the disturbances in grid voltage. All this caused huge rise in batteries usage, and poses the question about the availability of global resources of lithium, cobalt and nickel needed for battery production. The recent forecast is that these resources will be exhausted very soon in the decade 2030-2040. Thus, there is a strong need to search for new battery types, to maintain, at least partly, available lithium resources for more demanding applications. As a part of solutions having real perspective, the development of sodium-ion battery is currently in progress. In that sense, some perspective anode and cathode materials were considered.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78694818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"MODELLING OF PHASE EQUILIBRIA IN AlCu5Mg1 ALLOYS","authors":"B. Zlatičanin, B. Radonjić","doi":"10.7251/comen2101032z","DOIUrl":"https://doi.org/10.7251/comen2101032z","url":null,"abstract":"Al-based alloys were one of the first material types to which thermodynamic phase diagram calculations were applied. Since then improvements in modelling and the increase in computing power has enabled very accurate predictions to be made for phase equilibria in real multicomponent alloys.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82762482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"ROUGH PREDICTION OF OSCILLATIONS BY COMPUTING MAXIMAL INSTABILITY","authors":"Z. Rajilić, D. Malivuk Gak","doi":"10.7251/comen2201111r","DOIUrl":"https://doi.org/10.7251/comen2201111r","url":null,"abstract":"We use Newton’s second law of motion assuming combination chaos with stochasticity. For a measured time series, one can compute appropriate force and then better understand and roughly predict the behavior of the observed complex system. The force parameter describing instability is of the highest importance. We consider some mechanical experiments and the average global temperature.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78003595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"NONUNIVERSAL PROPERTIES OF SELF-INTERACTING POLYMER IN NON-HOMOGENEOUS ENVIRONMENT MODELED BY 3-SIMPLEX FRACTAL LATTICE","authors":"D. Marčetić, Sunčica Elezović Hadžić, I. Živić","doi":"10.7251/comen2101050m","DOIUrl":"https://doi.org/10.7251/comen2101050m","url":null,"abstract":"We have studied lattice self-avoiding polygons with attractive interaction between contacts which are nonconsecutively visited nearest neighboring sites. The lattice of choice is 3-simplex fractal lattice and the model represents a ring polymer in non-homogeneous solution whose quality depends on the interaction parameter. It has already been shown, by the renormalization group approach, that polymer on this lattice at any nonzero temperature can exist only in the extended phase. Universal critical exponents, which do not depend on the interaction strength, have also been determined. In this paper we are concerned with two nonuniversal quantities: the connectivity constant related with the free energy of the model and the mean number of contacts related with the internal energy. We have shown that the connectivity constant is an unboundedly increasing function of the interaction strength, while the mean number of contacts is an increasing function asymptotically approaching a limiting value equal to one half, which is the mean number of contacts in the case of Hamiltonian walks on the same lattice. This limiting value is expected, since in the limit of infinite interaction (or zero temperature) each self-avoiding walk on 3-simplex lattice becomes maximally compact and occupies all lattice points, i.e. becomes Hamiltonian walk.","PeriodicalId":10617,"journal":{"name":"Contemporary Materials","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85998527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}