The potential re-use of red mud in the building and construction industry has been the subject of research of many scientists. The presented research is a contribution to the potential solution of this environmental issue through the synthesis of potential construction materials based on red mud. A promising way of recycling these secondary raw materials is the synthesis of alkali-activated binders or alkali activated materials. Alkali-activated materials or inorganic binders based on red mud are a new class of materials obtained by activation of inorganic precursors mainly constituted by silica, alumina and low content of calcium oxide. Since red mud contains radioactive elements like 226Ra and 232Th, this may be a problem for its further utilization. The content of naturally occurring radionuclides in manufactured material products with potential application in the building and construction industry is important from the standpoint of radiation protection. Gamma radiation of the primordial radionuclides, 40K and members of the uranium and thorium series, increases the external gamma dose rate. However, more and more precedence is being given to limiting the radiological dose originating from building materials on the population these days. The aim of this research was to investigate the possible influence of alkali activation-polymerization processes on the natural radioactivity of alkali activated materials synthesized by red mud (BOKSIT a. d. Milici, Zvornik, Bosnia and Herzegovina) and their structural properties. This research confirmed that during the polymerization process the natural radioactivity was reduced, and that the process of alkali activation of raw materials has an influence on natural radioactivity of synthesized materials.

A avaliação de comportamento de tanques acoplados é de grande interesse industrial, por normalmente estarem presentes em várias partes diversos processos, como por exemplo, em empresas petroquímicas, de celulose ou tratamento de água. Este trabalho busca modelar um sistema de tanques em série a partir das medições feitas em uma unidade piloto do curso de engenharia química da UFCG. O projeto é constituído por dois tanques em série, um reservatório de alimentação e uma bomba centrífuga que é responsável pela alimentação do primeiro tanque. Para a modelagem do sistema foram adotadas duas abordagens: a lei de Ohm e a primeira lei da termodinâmica aplicada a sistemas abertos. A partir da análise dos resultados, observa-se a clara aderência dos dados experimentais através de validação estatística.

This paper presents new records and noteworthy data on the following taxa in SE Europe and adjacent regions: cyanobacteria Anagnostidinema amphibium, mycorrhizal fungus Tricholoma frondosae, stonewort Chara connivens, mosses Dicranum polysetum and Ulota intermedia, and dicots Eclipta prostrata, Paeonia daurica subsp. daurica, Ruta graveolens and Sorbus bosniaca.