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This paper presents the development of standardization in the field of energy efficiency, based on a review of available literature on this topic. The paper discusses the development of standardization of energy efficiency of household appliances, energy efficiency in buildings, energy efficiency in transport, standardization related to the use of renewable energy and energy management system standardization. The aim of this paper is to showcase the course of development and important events in the development of standardization in the field of energy efficiency, as well as to present an analysis of published articles on the topic of standardization of energy efficiency in prominent international journals. In research and formation of conclusions, analysis and synthesis methods are used.

The electromagnetic casting process fundamentals of EN AW 7075 Al-alloy casting, as well as the mechanical characterization results of this alloy forgings are presented in this paper. Forgings are obtained from the alloy casted by classical semi-continuous casting process and by electromagnetic casting process using two different frequencies. Results reveal that forgings obtained from the alloy casted by electromagnetic casting process have adequate values of mechanical properties and that proper choice of operating parameters can lead to shortening of this alloy processing.

The paper describes the real appearance of a new class of light sources. The technology progress allows the light emitting diodes (LED) to be applied for an in- and outdoor lightning. The special, high power diodes (HPLED) have too many advantages comparing to classical light sources and it is quite reasonable to expect their mass application in the indoor and outdoor lighting. The article contains a brief theoretical aspect of optics, explanations of the classical light sources parameters and typical examples. The performances of standard and high power LED are also included as well. The conclusions made at the paper end predict the massive usage LED for the lightning in a near future.

Certain procedures for protecting cotton fabrics against ignition and flame spread are described in the paper. There are two types of substrates presented - 100% cotton fabrics with different characteristics, varying type and quantity of active agents - antipyrene and certain processing factors. The objective of the research is to determine the efficiency of using the combination of potential antipyrenes (polymers, phosphorus, halogen, and nitrogen compounds) and to control other characteristics important for the quality of a textile product. Certain combinations resulted in an excellent fabrics protection against ignition. The burning time, as well as the smoldering, is minimal. Other indicators, such as mechanical characteristics or air permeability show less significant results, while the capillary properties and dimensional stability is satisfactory.

Electrolytic treatment of wastewater is a technique in which wastewater is treated by applying electric current through electrodes in the electrochemical reactor. This is actually a combination of many processes such as anodic oxidation, electro-coagulation and electro-flotation. The paper presents the influence of current density (5, 10, 20 mA/cm2) on the efficiency and reaction rate degradation of cyanide from cyanide wastewater in an electrochemical reactor with electrodes made of steel and stainless steel for 60 minutes of reaction time. This paper presents of a significant effect of current density and an.

Wild fire occurred in the summer 2007 on the Vidlic Mountain (Serbia) overspreading a huge area of meadows and forests. The aim of the study was to investigate the effect of wild fire on the content of heavy metals in plants Aegopodium podagraria, Hypericum perforatum and Chelidonium majus belonging to the families Apiaceae, Hypericaceae and Papaveraceae. Also, we examined the content of heavy metals in soil samples on which the test plants grow a year after fire. As control samples was investigated by the appropriate plant material and soil from the site in the immediate vicinity that was not affected by the fire. Metal content in the soil was determined in the fractions of extractible, bioavailable and pseudo total cations. The content of all examined heavy metals (Pb, Cd, Cu and Zn) is the biggest in pseudo total cations fractions and the lowest in bioavailable cations fractions. The exception is the land on which the plant A. Podagraria grows, because the content of copper and zinc was the largest in the fraction of extractable cations. The concentration of heavy metals in all fractions was always higher in soil samples that were exposed to the fire, except in the extractible metal cations fractions of A. podagraria and H. perforatum. Lead is characterized by the highest concentration in the soil of all three plant species. The lead content was much greater in pseudo total cations fractions. The underground parts of plants that were grown on both locations have a higher concentration of lead in relation to the above-ground portion. The content of zinc was higher in the plant samples than in samples of soil where the plants are grown. Above-ground parts of all three examined plants contain more copper than the corresponding underground parts of the plant. The underground parts of examined plants from location that were not exposed to the fire have higher levels of cadmium than plants from the localities which suffered from the fire.

This paper investigates the impact of the staining of cherry wood (Prunus avium L.) on the adhesion value of three most commonly used types of coatings in the wood industry: nitrocellulose (NC), polyurethane (PU) and water-based (WB) coating. Staining was done using two types of stains: water-based and nitro-based stain. Staining of cherry wood led to an increase in surface roughness, expressed by the parameter Ra for 49.1% when the surface was treated with water-based stain, and for 5.1 % when the surface was treated with nitro-based stain. The value of adhesion of coating on the substrate surface was measured by 'cross-cut test' and 'pull-off test'. Comparing different types of coatings, the samples lacquered with NC coating expressed the lowest value of adhesion (3.29 MPa), and the samples that were lacquered with PU coating and WB showed significantly higher adhesion values (6.96 and 7.91 MPa, respectively). Staining of cherry wood with water-based or nitro-based stains had positive impact on the value of adhesion of NC and PU coating, while the effect of staining on the adhesion of WB coating was not observed.

The results obtained during the recycling of spent nickel based catalysts that generate in the oil hydrogenation process are presented. Nickel based catalysts are used for selective hydrogenation of the highly active plants oils. The used catalysts are classified in the H11 category of hazardous materials; they are deposited on the site and are potentially dangerous to the environment. Laboratory experimental research defined optimal conditions (temperature, time and solid-liquid ratio) and technological process of catalysts recycling. Hazardous waste is being converted to the category of non-hazardous, and extracted nickel as nickel-sulphate represents commercial product. The degree of recovery of nickel is higher than 95%.

The paper includes a general discussion of reasons for the application of heat storage and phase change material as storage medium. A part of experimental results obtained by measuring during the process of paraffin phase change was presented. It was observed that in order to obtain lower temperature stratification during the heating process it is necessary to increase the number of volume heat sources in the thermal storage. .

Biomass can be considered strategic potential, not only because it is a renewable source of energy and it is widespread, but also because its application can provide a sufficient amount of energy to reduce emissions of CO2 and other greenhouse gases, resulting in a minimum negative impact on environment. This paper presents an overview of techniques for biomass burning, as well as technical and technological characteristics of plant for the production of energy from biomass in order to promote the implementation of renewable energy sources. It also presents the option and joint combustion of biomass and fossil fuels. The decisive factor in the increased use of biomass should be its low acquisition and operating costs, but the application of modern low-emission incinerator is economically viable only for large plants, because then gets maximum effect from the problem of fuel (straw and specially planted Culture (Miscanthus Sinesis)). .