The aim of the present study, set in the Polish-English context, is to discuss to what extent, if any, L1 competence (semantic, phraseological and grammatical) is influenced by the language contact, understood here as the (advanced) knowledge of L2, i.e. English. The research is based on the questionnaire consisting of 23 short excerpts taken from newspaper articles or texts published on the Internet, adapted by the author of the article. The texts in the questionnaire contain various kinds of borrowings and calques from English, such as semantic loans, loan translations (new phrases, collocations or idiomatic expressions) and grammatical constructions modelled on English. The questionnaire was given to two groups of informants: the main group (i.e. the bilingual one), consisting of 4th year students of English at the University of Silesia enrolled in the teaching programme, and the control group, consisting of students of various fields (excluding English or Polish studies) who declared limited knowledge of English. The respondents from both groups were given the questionnaire and their task was to read the sentences carefully and then to decide whether some words or phrases seemed incorrect or unnatural in a given context. The study has corroborated the view that language contact has some repercussions at the individual level: the knowledge of L2 may and does influence L1 competence. Not all the areas (semantic, phraseological and grammatical), however, are affected to an equal extent.

The aim of the research presented in this paper was to determine the effect of vessel scale on gas hold- up in gas-liquid systems. The agitated vessel with internal diameters of T = 0:288 m and T = 0:634 m was filled with a liquid up to the height H = T. For the purpose of measurements, two high-speed impellers were used: Rushton turbine impeller (RT) or A 315 impeller.Within the study, the following parameters were altered: superficial gas velocity, impeller speed, impeller type and concentration of aqueous sucrose solution. In addition, influence of the vessel scale on gas hold-up value was analysed. Experimental results were mathematically described. Equations (5)–(7) do not have equivalents in the literature.

Article presents the results of the effect of humidity on early shrinkage of normal concrete with variable W/C ratio. As known for a long time, shrinkage is dependent of many factors. One of them is the W/C ratio and the quantity of water which is located in the concrete mix. In article there were discussed changes taking place in the concrete mix, the methods of research and the partial results obtained by the authors of the paper. Shrinkage is a phenomenon well known and studied by various research centers. The total amount of shrinkage may depend on various factors such as humidity, temperature, composition of the concrete mix, the W/C ratio, the size of the item. The study was conducted to determine the amount of shrinkage in its early stages. It is very important for concrete floors contractors, precast manufacturers to start at the right time finishing work and prevent the formation of shrinkage cracks.