Preparation of samples by microwave technique consists of large number of phases, from taking samples till receiving homogeneous solution for instrumental analysis. Samples preparation can include combination of drying, wetting, extraction, digestion, analytic separation and solvent removing. The analysis of content of heavy metals in potato from B...

By M. B. Rajković, I. D. Sredović, S. R. Milojković, D. V. Tošković, D. D. Stanojević

Reaction between a warm water mixture of pyridoxal hydrochloride (PL.HCl), and Smethyilisothiosemicarbazidehydroiodide (SMeTSC.HI) in the presence of Na2CO3 .10 H O, we got pyridoxal S-methylisothiosemicarbazone (PLITSC; H2L). Ligand with appropriate Cu salt is coordinated, to give next complex: dark-brown, penta coordinated, square-pyrami...

By S. Ivković, V. Jevtović

The influence of polyacrylamide (PAA; Mn between 5∙103 and 1.5∙106 gmol-1 ) on hydrogen evolution reaction at the polycrystalline gold in 0.5 M H2SO4 was studied using potentiodynamic measurements (5 mV/s) in the potential range from 0 to -0.6 V/she. It was concluded that formation of protective layer of PAA, adsorbed on the electrod...

By D. Ĉamovska, M. Cvetkovska, T. Grčev

Biodiesel is a mixture of methyl esters of long chain fatty acids, produced typically by alkalicatalyzed transesterification from vegetable oils. Biodiesel products in the EU must meet EN 14214 quality standard specification. In this specification, values of physical properties and impurities for commercial products are set out, including viscosity...

By J. Sadadinović, A. Kalfić

There are three parameters that influences hydrolyses on milk and fermented milk products. Active acidity (pH) is one of that factors that determines speed of reaction and can influence on specific enzyme substrate. In production of yogurt, hydrolyses is measured by amount of peptides on different pH value. Maximum pH is determined to obtain maximu...

By J. Tomovska, N. Gruevska, N. Tomovska

This paper presents results of theoretical research in changed optical properties due to the presence of boundaries and changes of boundary parameters in nanofilm-molecular crystals. The energy spectrum of excitons and their spatial distribution along the axis limits (in layers) were found through analytical and numerical calculations. The relative...

By S. Pelemiš, S. Armaković, J. P. Šetrajčić

In this paper the aim was to create a basic model for total quality management in the organization of the textile production, with an emphasis on Statistical Process Control (SPC) in the design and development process that will completely satisfy the requirements, the needs and the desires of the buyers and all the participants in the business rela...

By B. Gjorgjevska, S. Kjortosheva, V. Chepujnoska

Investigation of the composition of elements in drinking water, from water network of Belgrade city, with indirect method. This method is based on the scale that is made with precipitation from the water during heating, indicated presence of alkali and alkaline earth elements to a greater extent and heavy metals which is quite expected. Somewhat un...

By M. B. Rajković, Z. Tomić, M. D. Stojanović, A. Đorđević, M. M. Sudar

Consumption of red mul, of huge ballast in alumina production is nightmare for scienists who are working in the area of industrial metallurgi, one dey will become reality. Among other things of cement industry is going to help regrading assortment of products and diversity of raw material base. In this document, theoretical bases of the mentioned a...

By J. Mikić, M. Sudar

In the introductory part we give definitions and relationships to determine the reliability and probability of failure of technical systems. After that, the analysis and calculation of reliability, we proposed method, based on the construction of tree failure in the form of logical structure. The second part was performed to verify the model set on...

By B. Pejović, D. Vujadinović, M. Perušić