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In this study, three types of recycled waste paper fibers were used to manufacture cement composites reinforced with recycled cellulosic fibers. Waste cellulosic fibers in quantity of 0.2, 0.3, and 0.5 wt.% were added to cement mixtures. Physical properties such as density, water capillarity, water absorbability and thermal conductivity of fiber cement composites were studied after 28 days of hardening. However, durability of composites was tested after their water storage up to 90 days. Final results of tested properties of fiber cement composites were compared with cement reference sample without cellulosic fibers. [ABSTRACT FROM AUTHOR]

The article evaluates a moistened office building built before 1950 after the interval of three years, where a non-destructive moisture rehabilitation was performed using the developed hydrophilic plasters. The evaluation is carried out by means of Delphin software allowing you to take into account the moistening effects taking place in the construction over time and providing exact outputs in the form of specific values describing the moisture content achieved in the masonry. The simulation is based on the measured moisture parameters obtained during the three years of building monitoring, mutually comparing the so-called soft plaster rehabilitation methods according to the WTA with plasters based on polyurethane fillers and plasters based on aluminosilicate waste created during the production of cellular concrete. [ABSTRACT FROM AUTHOR]

In recent history, asbestos cement pressure pipes were widely used for delivery of potable water from water sources to human settlements. Nowadays, most of the asbestos cement water mains are approaching the end of the service life. Although asbestos cement water mains are not considered to represent a significant risk to public health when in normal use, asbestos fibres released into air during rehabilitation of water mains pose a cancer and lung disease hazard. The contribution deals with problems of rehabilitation of asbestos cement water mains in the Czech Republic as well as with safety and disposal issues. The first part of the contribution briefly describes production of asbestos cement pipes and provides information on installation of asbestos cement water mains as second part deals with health effects of asbestos on humans. The final part of the contribution focuses on principal laws and regulations concerned with asbestos waste management in the Czech Republic and safety in the workplace during rehabilitation of asbestos cement water mains. [ABSTRACT FROM AUTHOR]

The article describes the optimization of the purification process of industrial waste waters containing sodium N-chloro-benzenesulphonamide (ChBSA) and sodium ptoluenesulphonamide (TSA). The article presents the results of an experimental research dealing with the retention period of industrial waste water in waste-water treatment plant, the potential of biological degradation of industrial waste waters from the production of ChBSA and TSA and the choice of a suitable substrate for activated sludge supporting the biodegradation of ChBSA and TSA. The results of the experiment clearly show that the ideal contact time of activated sludge in the biological section of an industrial waste-water treatment plant and the waste water from the production ChBSA is 6-7 hours. The suitable ratio for biodegradation of industrial waste water from the production of ChBSA and TSA is 75% ChBSA: 25 % TSA. [ABSTRACT FROM AUTHOR]

The time of university studies is a period during which an individual must fulfil a variety of tasks according to a pre-determined schedule. He/she should, for example, attend lectures, seminars and exercises, prepare and present seminar papers, perform the duties necessary to obtain the individual credits, pass exams from the given subjects, be active, independent, creative and responsible for his/her study results. Activity, independence, responsibility, creative approach, knowledge and awareness of his/her objectives in life, including the way how to achieve them are important attributes affecting not only the degree of study success and life satisfaction of the students, but also their eventual tendency to procrastination. The content of the word procrastination is not defined in a uniform way by the experts. Where experts agree is the fact that the numbers of procrastinating individuals have been increasing and that university students represent a notable share on this number. The situation regarding procrastination of the students of the VŠB - Technical University of Ostrava and the Slovak Agricultural University in Nitra has been investigated using a questionnaire. [ABSTRACT FROM AUTHOR]

This article describes the problems of cleaning sewerages in order to ensure their functioning and to extend their working life. It describes the determination of hydraulic losses, ensuring safe disposal of waste water through the designed sewerage system. Attention is also paid to the sewerage shapes and currently used mechanical and hydro-mechanical methods of combined and separate sewerage system cleaning [ABSTRACT FROM AUTHOR]