ACTIVATION OF DOMESTIC ALUMINA AND TESTING OF POSSIBILITIES FOR APPLICATION IN SOME MINERAL BASE OILS RAFINATION

Mineral base oils are extracted from oil fractions of naphta that has boiling point of over 350 °C, and contain different kinds of carbohydrates and hetero-compunds. Removal of unwanted compunds from mineral base oils in domestic rafineries is made by rafination of imported commercial clays. For ther eventual replacement there has been conducted a testing of various domestic adsorbens. In this paper, examples of natural alumina from the vicinity of Sipovo are previously activated with sulphuric acid, and then used for rafination of naphtenic and hydrocracked base oil in laboratory conditions. Emerged changes on mineral base oils are followed by corresponding standardised methods. Results of testing showed that, by refining the given base oils with activated alumina, one can achieve good results and therefore further explorations shoud be continued, because of their commercial application in semi-industry and industry condition

Potential for a new multimillennial tree-ring chronology from subfossil Balkan River oaks

A total of 272 oak (Quercus sp.) samples have been collected from large subfossil trees dredged from sediment deposited by the Sava and various tributary rivers in the Zagreb region of northwestern Croatia, and in northern Bosnia and Herzegovina. Measurement series of tree-ring widths from these samples produced 12 groups, totaling 3456 years of floating tree-ring chronologies spread through the last ca. 8000 years. This work represents the first step in creating a new, high-resolution resource for dating and paleoenvironmental reconstruction in the Balkan region and potentially a means to bridge between the floating tree-ring chronologies of the wider Mediterranean region and the continuous long chronologies from central Europe.Center for Mediterranean Archaeology and the Environment (CMATE) Special Issue, Joint publication of Radiocarbon and Tree-Ring Research, also cited as Pearson, C., Ważny, T., Kuniholm, P., Botić, K., Durman, A., & Seufer, K. (2014). Potential for a New Multimillennial Tree-Ring Chronology from Subfossil Balkan River Oaks. Radiocarbon, 56(4), S51-S59.This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

INFLUENCE OF USED LUBRICANTS TO ENVIRONMENT

In the according with very intensive application of lubricant, the very large amounts of used lubricants which are harmful to the environment and human health are produced. In the European Union countries, the problem of used lubricants are permanently solved and many directives about this problem is setted (in the starting EEC Directive 75/439 and the end 2008/98/EC). In undeveloped countries similar with Bosnia and Herzegovina there is no organized management of used lubricants yet, because we do not have adequate legislation as well as the bad environmental awareness. In due to these facts used lubricants, although treated as hazardous waste are improperly disposed near roads, streams, fields, used for burning weeds, as a fuel, for impregnating wood, etc..). These effects can be dangerous for the environment and human health. Another problem is that these lubricants are mostly poorly degradable, and some of their components are not only toxic, but carcinogenic properties. In this paper, the method of disposal of used lubricants in the municipality of Zvornik is tested. The study was conducted by interview of institutions, public companies, private companies, craft stores and citizens, and collecting statistical data. In order to study used lubricants, analysis of water and soil from selected location (near roads, companies and auto repair shops) is performed