Intenzitet i efikasnost investicija u fiksne fondove prerađivačke industrije su jedan od osnovnih faktora održivog rasta BDP i sprovođenja strukturnih promena. Zemlje u razvoju i tranziciji, sa niskim nivoom bruto domaćeg proizvoda per capita ne mogu da smanje ekonomsko zaostajanje za razvijenim zemljama bez bržeg rasta i povećanja intenziteta i efikasnosti investicija u prerađivačkoj industriji. Stoga su predmet istraživanja ovoga rada implikacije investicija u fiksne fondove prerađivačke industrije Srbije. Cilj istraživanja u radu je da ukaže na značaj efikasnog sprovođenja investicione politike, kao i na važnost investicija kao sredstva sprovođenja industrijske politike. Centralno pitanje je kakvi su efekti investicija u osnovne fondove prerađivačke industrije Srbije. Može se zaključiti da je i pored rasta nivo investicija nizak u odnosu na razvojne potrebe i privrede i prerađivačke industrije. U narednom periodu neophodno je više se oslanjati na sopstvene snage, domaću štednju i povećati efikasnost investicija zbog tehnološke modernizacije, rasta produktivnosti i konkurentnosti sektora prerađivačke industrije Srbije.

Characteristics of air hardening steel are high hardness and low impact toughness. In order to increase the impact toughness while retaining replace with the high hardness value numerous research added. One of the ways to achieve this is the alloying of specified steel with vanadium and application of appropriate heat treatment. Vanadium affects the solidification process of these alloys by narrowing of the temperature interval of crystallization. In addition, vanadium formed V6C5 carbides that block the growth of austenitic dendrites and structure makes fine-grained. Vanadium which forms V6C5 carbides is partly distributed between present phases in the steel, carbide (CrFe)7C3 and austenite. Also, the presence of vanadium can enable the formation of (CrFe)23C6 carbide and its precipitation in austenite during the cooling process. In local areas around fine carbide particles, austenite is transformed into martensite. In other words vanadium reduces the amount of remained austenite and so improves hardenbility of the steel. In this way, better technical characteristics of these steels are obtained.

Economic development is a multidimensional and complex process; apart from economic growth, it also encompasses changes in the structure of an economy, as well as changes in resources, institutions, technology and processes and numerous other changes in a social system. When developing countries are concerned, such as the Republic of Serbia (RS), structural changes are necessary so as to ensure in order to faster growing gross domestic product (GDP) per capita. Practice shows that, in order to achieve sustainable economic growth and development, efficient changes in the economic structure need to be made. They have an ECONOMIC DEVELOPMENT OF THE REPUBLIC OF SERBIA DETERMINED BY THE SECTORAL STRUCTURE OF THE ECONOMY

The development of polymers obtained from renewable raw materials is important because it is known that the fossil sources will be depleted in the future. Due to this fact, the possibilities for the synthesis of polyurethanes based on renewable resources increases. This work analyzes the properties of polyurethane materials obtained from the renewable resources. Polyurethane elastomers were prepared by a two stage process in solution, which involved the synthesis of the pre-polymer and synthesis of the polyurethane elastomer. As a polyol component, poly (propylene glycol) was used. Isophorone-diisocyanate and hexamethylene diisocyanate were employed as isocyanate components. For some samples, petrochemically obtained chain extender, butanediol, was replaced by biobased product isosorbide. Characterization of polyurethane materials was carried out by infrared spectroscopy with Fourier transformation, thermogravimetric analysis and differential scanning calorimetry. The properties of synthesized polyurethane materials were improved by adding the nanoparticles in various proportions.

<p style="text-align: justify;">Austempered Ductile Iron is a class of ductile iron subjected to a specific heat treatment process (austenitization and austempering). The heat treatment gives to that type of Ductile Iron an excellent mechanical properties and an especially good strength-to-weight ratio. However, designers in most cases are unfamiliar with this material that can compete<br />favorably with other type of metallic materials (steel, aluminum, etc). The high tensile strength of ADI is the result of its unique ausferrite microstructure. In this paper, an example of Ductile iron sample production is presented.</p>