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Micro-mechanical performance of concrete used as recycled raw material in cementitious composite
Hrbek, Vladimír ; Koudelková, Veronika ; Prošek, Z. ; Tesárek, P.
The reduction of industrial pollution is recently one of main goals over all fields. In civil engineering, re-cycling of structural waste provides wide opportunity contributing this effort. This paper focus on re-use of concrete waste, which after further processing can be used in new constructions as partial supplement to the mixture. To investigate the impact of re-cycled concrete addition, it is necessary to determine mechanical and structural parameters of individual phases in the “raw” material. For this purpose, grid indentation and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM, EDX) are combined to determine properties of concrete sample.
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Influence of dispersed particles on utility properties od polyvinyl alcohol-based nanotextiles: macromechanical properties
Rácová, Z. ; Nežerka, V. ; Ryparová, Pavla ; Kromka, Alexander ; Tesárek, Pavel
The paper deals with the influence of different dispersed particles on utility properties of polyvinyl-alcohol (PVA) based nanofiber textiles. The purpose of the dispersed particles was to produce textiles of antibacterial character, and these were added into water-polymer solution, which was used for electrospinning in two various ways: in form of copper and silver ions, or in form of diamond nanoparticles. In order to assess the strength of textiles, macromechanical testing of modified PVA-based nanofiber textiles was carried out on samples with variable weight per area in range between 0.5 and 5 g/m(2). The obtained results were compared with the results of measurements on plain reference samples. The study revealed that the addition of silver ions causes the strength and stiffness reduction, the addition of copper ions has an opposite effect, while the diamond nanoparticles did not have any significant influence on the mechanical properties.\n
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Verification of the use of pva based nanofiber textiles as a rehabilitation for the structures attack by wood decaying fungi
Rácová, Z. ; Ryparová, Pavla ; Wasserbauer, R. ; Nežerka, V. ; Tesárek, Pavel ; Demo, Pavel
The presented paper is focused on the investigation of antifungal properties of nanofiber PVA-based textiles with incorporated copper and silver ions. In particular, the ability to prevent the growth of Dry rot fungus (Serpula lacrymans) was studied in laboratory conditions. For that purpose, the Petri dishes with malt agar were inoculated with square cut-outs of seed stocks, consequently covered by the nanofiber textiles and kept in an incubator at 28 degrees C. The fungal growth had been monitored and recorded at regular intervals for 28 days. The comparison of the individual treatments (PVA, PVA + Ag, PVA + Cu, PVA + Ag + Cu) is finally discussed.\n
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Algicidal properties nanofibrous fabrics doped by metals
Ryparová, Pavla ; Wasserbauer, R. ; Rácová, Z. ; Demo, Pavel ; Tesárek, Pavel
The paper presents a novel protection against algae by nanofiber fabrics doped with metal ions. Nanofiber textiles were prepared by electrospinning on the Nanospider LB 500 device, equipped with cylindrical electrodes of a length 600 mm and electrode distance about 140 mm. The produced nanofiber textiles had a specific weight between 2 and 4 g/m2. The entire surface was covered with algae commonly accompanied by bacteria. The sample had placed in the middle of circular dishes having the diameter 20 mm. The cultivation took place at light environment in common laboratory conditions. Algicidal effect was evaluated as the resulting halo size and quality around the sample. The PVA treated sample had not produce any halo effect, unlike the samples with the addition of metal salts (AgNO3, CuSO4 center dot 5H(2)O) that exhibited the halo effect dependent on the concentration the salts, usually ranging from 0.3-2 mm, giving the evidence about their algicidal properties.\n
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Influence of incorporated nanodiamond particles on mechanical properties of composite material based on multi-layer PVA nanofiber textiles
Prošek, Zdeněk ; Indrová, K. ; Rácová, Z. ; Ryparová, Pavla ; Nežerka, V. ; Topič, J. ; Tesárek, Pavel ; Kromka, Alexander
The present study investigates the influence of NDP on mechanical properties of multi-layer PVA nanofiber textiles. The particles of a diameter equal to 5 nm were incorporated into double- and triple-layer textiles, while the single-layer samples were prepared as the reference. The diameter of PVA nanofibers varied from 100 to 300 nm. We characterized the tensile strength, stiffness and ductility of fabricated nanofibers by using a conventional method – a tensile test. We found that the NDP-enriched nanofibers reveal antibacterial character. However, none or negligible influence of NDP additions on the tested mechanical properties was observed.
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Analysis of the processes and tools of campaign responses evaluation
Hlaváčková, Lýdia ; Novotný, Ota (advisor) ; Tesárek, Petr (referee)
This thesis is specialised to analyse clients responds from banking industry to mar-keting campaigns. For purpose of such study are from the view of the information systems essential Customer Relationship Management systems, CRM systems, their operational part, with which are working all the employees and also analytical part, which serve for agregation a usage information of the operational part for desicion making. For the sake of correct understanding of the business logic of these systems is thesis concerning also area of direct marketing, which is object of CRM marketing campaigns. From theoretical point of view is suitable in the name of marketing campaigns evaluation work with Customer Intelligence and its selected topics. As a case study has been used real situation of the bank existing on the czech ban-king market, which is in current time working of implementation of a new CRM system Siebel. Situation in the bank and also on the project has dynamical charakter. Target of the thesis is to find out and provide the way how CRM system supports scoring of campaign succes, which is important for decision making about products offered to clients and about choice of appropriate communication. There are also mentioned other options of develop-ment these analytical tools.
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