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Wastewater treatment plants contribute to the removal of pollutants from wastewater following the norms and regulations on the quality of the wastewater and therefore are an indispensable part of wastewater treatment and environmental protection. Each stage of wastewater treatment consumes a significant amount of energy. The need to meet rapid population growth and stricter conditions in terms of effluent quality requirements has led to an increase in energy consumption in wastewater treatment plants. Energy consumption is a bottleneck in wastewater treatment plants and, as the number of these plantsin the world increases, the issues of reducing energy consumption and energy efficiency are beginning to attract attention. It also contributes to the cost increase in wastewater treatment plants. Analysis and prediction of energy consumption are key factors for energy savings. Energy consumption in wastewater treatment plants is affected by many factors. However, information on energy consumption and potential for energy recovery/production and energy efficiency in wastewater treatment plants remains very limited. This paper reviews the literature and analyzes the energy consumption in these plants and the possibility of increasing the energy efficiency of these plants through the use of renewable energy sources and energy recovery from the plant itself. ; Published

T his paper presents the main development trends of the world's energy market and describes the fundamental energy security principles. It analyzes the European energy sector, production and consumption, and the European Commission's legal regulations regarding the energy security. The results of the Russian energy sector are discussed through an analysis of the expected effects of conceptual development and the Russian Government policy. The relations between the EU and Russia are analyzed on the EU level as well as on a bilateral level. In the conclusion, the paper offers an overview of the current EU energy security and an answer to the question: 'Can Russia be a reliable energy partner for the EU?'.

The core of the dissertation is to improve energy efficiency of small hydropower plants (SHPPs). The focus is to solve the problems of (1) decreased electricity production during low water flows and (2) inadequate functioning of multi-chamber settling basins because of an uneven flow distribution among the chambers. The latter problem has been solved by an original methodology, which is an upgrade on the traditional usage of CFD and analytical models. The methodology is among the scientific contributions that are:  a method for the iterative finding of a technical solution by the use of a CFD and an ancillary analytical model, which is a guide for a complex and slow CFD model towards an optimal geometry;  a method for the determination of local pressure drops (minor losses) for complex geometrical shapes with multi-dimensional flow patterns using: CFD simulations, regression analysis, and indirect validation;  the application of modern software for the design, optimization, modeling, and modernization of SHHPs.  a novel solution for simultaneous equalization of flows among the chambers of a multi-chamber settling basin and the dissipation of turbulent kinetic energy. These results were implemented on a case study, which includes two cascade SHPPs with a common side water intake and nominal installed capacities of 1.220 MW and 1.327 MW. The solving of both problems resulted in technical solutions for:  the determination of an optimal configuration under existing conditions (gross head, turbine types, pipeline diameters) by the use of new turbine(s) and independent or coupled operation of two run-of-the-river SHPPs;  the equalization of flows among the chambers of a multi-chamber settling basin and the dissipation of turbulent kinetic energy by the use of: (a) pillars with vanes in a common inlet zone and (b) sluice gates with tranquilizing racks. The solution of the (1) problem increased the electricity production by 4.8% and the solution of the (2) problem reduced the total loss by 8%. The results are ...

The aim of this paper is to point out the problems in the field of energy efficiency in Serbia and the needs for systematic measures for energy efficiency improvement in order to create appropriate conditions for sustainable industrial growth and development. The paper is consisted of three chapters and concluding remarks. In the first chapter was emphasized very low level of energy efficiency in Serbia, as well as very high energy intensity. This chapter provides also an analysis of structure of energy consumption in Serbia and selected neighboring countries. The legal framework for energy efficiency improvement in European Union and Serbia is presented in the second chapter of the paper. The adequate measures suggested by national policy for energy efficiency in order to stimulate industrial development are described in the third chapter. Finally, the last chapter summarizes key messages of the paper.

This paper presents an analysis of the implementation of sustainable architecture principles in designing the double-skin façades, through the case study of the business complex at the corner of Kralja Milana and Kralja Milutina streets in Belgrade. Double-skin façades have the most frequent use in office buildings' design showing significant results in energy saving. By applying this system, expected thermal gains in summer and thermal losses in winter are reduced, as well as the level of noise. Consequently, the inner comfort conditions are improved. This type of façade provides lower exploitation expenses, even though the initial building investments are higher.

The art of Francis Bacon is positioned as a London school of figurative painiting of the second half of the twentieth century, and as such it is the most direct reflection of the post-war traumas of the Nazi regime that befall Europe and the world. It was exactly at the time, at the intersection of social, economic, scientific and technological and cultural practices, that a Western neoliberal order was formed. It is a sample or archeological/historical layer also studied by post-structuralists Michel Foucault, Gilles Deleuze, Felix Guattari. This text is an attempt of explication of certain links in the opinion that connect the painting of Francis Bacon and the theory of post-structuralism, which are focused on the issues of development of biopower within certain historical sites. Namely, post-structuralists realise that archeological layers are volatile historical categories, and each of them is an independent social and cultural creation. Bacon authentically connects these historical layers through his visual language, referring to older painters such as Velasquez, Rembrandt, Ingres or Van Gogh. Thus Bacon re-examines the status of the subject (conceptualises life by the powers of death using human body) and its liberties both in liberal and in neoliberal societies. ; Published

Tehnološki postupak dobijanja metil-estara masnih kiselina iz suncokretovog ulja u prisustvu sirovog biodizela kao kosolventa i CaO kao katalizatora testiran je na laboratorijskom nivou. Istraživanje je urađeno radi validacije tehnološkog procesa, određivanja prinosa i sastava MEMK, kao i mogućnosti ponovnog korišćenja izdvojenog katalizatora u reakciji, bez ikakvog dodatnog tretmana prečišćavanja ili kalcnacije. Definisan tehnološki postupak je šaržnog tipa i obuhvata sedam faza jednog ciklusa: aktivacija katalizatora, metanoliza suncokretovog ulja, izdvajanje katalizatora centrifugiranjem, uparivanje metil-estarske faze (tj. sirovog biodizela) i sušenje biodizela.

This chapter provides an overview of the basic characteristics and methods of using wind energy, biomass, and geothermal sources to generate electricity. The potential for using wind energy was considered, as well as the existing capacities in Serbia. The complete wind generator system is technically described, from the mechanical conversion of wind energy, electromechanical conversion in electric generators to power conversion, and adaptation to the requirements of the electrical network. After a general description of biomass potential, atten tion is focused on types of bio-energy, which are suitable for use in systems for electricity generation (biogas, pellets). A description of the complete plant, operation characteristics, and the situations in the World and Serbia are given. For geothermal sources, a brief overview of the potential, history, globally installed capacitances, and methods for conversion into electricity is given. The possibilities of their usage for production of electrical energy in Serbia are discussed. У овом поглављу дат је преглед основних карактеристика и начина коришћења енергије ветра, биомасе и геотермалних извора за добијање електричне енергије. Размотрен је потенцијал за коришћење енергије ветра, као и постојећи капацитети у свету и Србији. Технички је описан комплетан систем ветрогенератора, од механичког претварања енергије ветра у ветротурбини, електромеханичке конверзије у електричним генераторима до електричног претварања и прилагођења захтевима електро мреже. После општег описа потенцијала биомасе, пажња је усмерена на био-енергенте, који су погодни за коришћење у системима за генерисање електричне енергије (биогас, пелет). Дат је опис комплетног погона био електране, карактеристике рада и стање инсталисаних капацитета у свету и Србији. За геотермалне изворе (геотермалну енергију) дат је кратак преглед потенцијала, историјата, инсталисаних капацитета у свету и метода претварања у електричну енергију. Размотрене су могућности њиховог коришћења за генерисање електричне енергије у Србији. Посебна издања ; књ. 707. Одељење техничких наука ; књ. 42

The subject of doctoral thesis includes the selection of packaging material and packaging conditions, packaging of traditional bakery product phyllo dough pastry with cheese, as well as the preservation of the product during the storage period. Partially baked phyllo dough pastry with cheese have been produced and packed into five and seventh layer polymeric bags, by using atmospheric and modified atmospheric packaging conditions, with and without the addition of the oxygen scavengers. After the packaging, phyllo dough pastries have been stored, and the dynamics of researches has been referred to: 0, 2, 4, 8, 12 and 16 week of storing.Researches of packaging material and the product of packaging have been conducted. Examination of packaging material includes: physicochemical and structural properties, barrier properties, concentration of gases inside the packaging and the quality of welds. Examination of the product of packaging includes: physicochemical properties, sensorial properties and microbiological properties of the phyllo dough with cheese.Applied packaging materials have shown an adequate physical, mechanical and structural performances. Furthermore, both packaging materials have shown good barrier characteristics against examined gases. By the calculation of total oxygen volume, which might penetrate throughout packaging materials during storing period, it can be concluded that the application of 100 ml oxygen scavenger is sufficient to provide the storing of phyllo dough pastry, packed in both packaging materials, during a period of 122 days (16 weeks) without oxygen concentration changes higher than 1%. The analysis of gas concentration in packaging has shown that the smallest oscillations of gas concentration during the storage have been determined inside the packaging of five and seven layer packaging material, in air conditions by using oxygen scavengers.Physicochemical performances (acid number, peroxide value, moisture content and aw value) of the samples vary depending on the packaging material and the packaging conditions, during the storage period. The storage period affects the sensorial quality of phyllo dough pastries. After sixteen weeks of storage, phyllo dough pastry with cheese, packed into five and seven layer packaging material, in air atmosphere, with the addition of oxygen scavenger, did not show the increase of the total number of yeasts and molds.Based on the goals, conducted research and results obtained, it might be concluded that suggested packaging materials, as well as the packaging conditions contribute to the additional sustainability of traditional bakery product - phyllo dough pastry with cheese. By the application of barrier packaging material, and combining the atmosphere packaging conditions and the oxygen scavenger it is possible to store phyllo dough pastry for a longer period. Predmet doktorske disertacije obuhvata izbor ambalažnog materijala i uslova pakovanja, pakovanje tradicionalnog pekarskog proizvoda pite sa sirom, kao i očuvanje proizvoda tokom skladištenja.Polupečene pite sa sirom su proizvedene i pakovane u petoslojne i sedmoslojne polimerne kese, pri atmosferskim i u uslovima modifikovane atmosfere pakovanja, sa dodatkom i bez dodatka sakupljača kiseonika. Nakon pakovanja, pite su skladištene i ispitivane po sledećoj dinamici: 0, 2, 4, 8, 12 i 16 nedelja skladištenja. Izvršena su ispitivanja ambalažnih materijala i ambalaže, kao i upakovanog proizvoda. Tokom ispitivanja ambalažnih materijala i ambalaže određivana su: fizičko-hemijska i strukturna svojstva ambalažnih materijala, barijerna svojstva ambalaže, koncentracija gasova u ambalaži i kvalitet formiranih varova. Ispitivanja upakovanog proizvoda su se odnosila na: fizičko-hemijska svojstva pite sa sirom, senzorska svojstva pite sa sirom i mikrobiološka ispitivanja pite sa sirom.Primenjeni ambalažni materijali su pokazali odgovarajuća fizičko, mehanička i strukturna svojstva. Takođe, oba ambalažna materijala pokazuju dobre barijerne karakteristike na ispitivane gasove. Izračunavanjem ukupne zapremine kiseonika koja može biti propuštena kroz ambalažu tokom skladištenja je utvrđeno da je upotreba sakupljača kiseonika od 100 ml dovoljna da omogući skladištenje pite sa sirom, pakovane u obe vrste ambalaže, u vremenskom periodu od 122 dana (16 nedelja), bez promene koncentracije kiseonika veće od 1%. Analizom koncentracije gasova u ambalaži je utvrđeno da su najmanje oscilacije merenih gasova tokom skladištenja pokazali uzorci pakovani u petoslojne, kao i sedmoslojne kese, u atmosferi vazduha sa dodatkom sakupljača kiseonika. Fizičko-hemijska svojstva (kiselinski stepen, peroksidni broj, sadržaj vlage, aw vrednost) uzoraka pita sa sirom su se menjala tokom skladištenja, zavisno od vrste ambalaže i uslova pakovanja. Period skladištenja utiče na senzorski kvalitet proizvedenih pita sa sirom. Nakon 16 nedelja skladištenja pita sa sirom upakovanih usa sirom kese od petoslojnog i sedmoslojnog ambalažnog materijala, u atmosferskim uslovima, sa dodatkom sakupljača kiseonika, ne dolazi do promena ukupnog broja kvasaca i plesni.Na osnovu ciljeva doktorske disertacije, izvršenih ispitivanja i postignutih rezultata, može se zaklučiti da su predloženi ambalažni materijali, kao i uslovi pakovanja doprineli produženju održivosti tradicionalnog pekarskog proizvoda - pite sa sirom.Primenom barijernih ambalažnih materijala, kombinovanjem atmosferskih uslova pakovanja i sakupljača kiseonika, moguće je skladištiti pite sa sirom u dužem periodu.

In recent years, sustainability and sustainable development have become very topical issues in many segments of the economic environment. How to store and retail occupy an important place in the economy of a country, and the concept of sustainable development has its place in retail. In fact, the concept of sustainable development, with all its components, retail is specific, and the companies on the basis of trying to create and improve the long-term competitive advantage. Given these facts, the subject of this work is the application of the concept of sustainability and sustainable development in retail. The aim is that, based on the experience of international and national retail chains, highlight the importance of the concept of sustainability has retail.