Now showing 1 - 5 of 92
- research articleBrožek, MilanAkademija : Aleksandras Stulginskis University, 2013Worldwide increasing energy demand is today permanently covered by a majority of non-renewable energy sources, namely by coal, crude oil and natural gas. This causes the rapid decline of their reserves and the time gets near when they will be run out. Therefore in last years the exploitation of renewable energy sources is permanently preferred. One of alternative fuel forms is the fuel on the basis of paper waste. In this paper the results of tests are published, which were carried out using six sorts of recovered paper and board (group and grade 1.05, 1.07, 2.01, 2.05, 2.07 and 2.08 according to ČSN EN 643), pressed in form of briquettes. During the tests following briquettes parameters were watched: moisture content, ash amount, length and diameter, weight, density, rupture force and mechanical durability. It was proved that briquettes made from recovered paper and board are compared with briquettes from wood waste are of high density, high mechanical durability and for their rupture the relatively high force is necessary. But at the same time they have high ash amount and low combustion heat.
- research article
;Cidlina, Jan ;Müller, MiroslavValášek, PetrAkademija : Aleksandras Stulginskis University, 2013This paper is focused on the necessity of chemical cleaning of the adherent surface, it means the effect of the attachments in the interlayer of the adherent and adhesive. To describe the process of need or absence of chemical cleaning process of adherent surface, that affecting the ultimate strength of adhesive bond, one-component and two-component epoxy resins, polyester resins and cyanoacrylates were used. Laboratory tests of adhesive bond were carried out using the standardized test specimens made according to the standard CSN EN 1465 from the constructional plain carbon steel S235J0, AlCu4Mg, Al99.5 and stainless steels. 4 2
- research article
;Henc, Petr ;Cidlina, JanMüller, MiroslavAkademija : Aleksandras Stulginskis University, 2013Adhesive bonding technology is dynamically evolving method of the material bonding and that is the reason of its using in the huge range of the industries. In reference to growing evolution, the needs for continuous testing and limits determination of the adhesive bonds grow to keep bonded structures secure. Many producers mention the adhesive resistance to moisture or water in a product list. The research showed that adhesive resistance to liquid mediums is lower and ultimate strength decreases with the exposure time. Experimental data also show that mechanical properties of epoxy adhesives are gradually restored. 4 2 Effect of solar radiation on thermal performance of external wall structures based on long-term measured dataPublicationresearch article ;Kiviste, Mihkel ;Lindberg, RalfLeivo, VirpiAkademija : Aleksandras Stulginskis University, 2013This paper discusses some of the factors affecting the energy consumption of different external wall structures in northern climate. The studies have been conducted at the Department of Civil Engineering at Tampere University of Technology (RTEK/TUT) during the past 16 years. As one of the outputs measured data from 6 test buildings (plus six-year data from additional 2 test buildings) has been built up. The level of detail (520 sensors in each building), amount (after each 20 seconds), long-term (measuring period of six and ten years) and coherency (measured at the same time at the same conditions) makes that data unique in Finland as well as in Europe. Up to 50% differences were found in the measured and calculated heat losses. Possible reasons for such a discrepancy are described and discussed. It has been focused on the effect of solar gains to thermal performance of massive exterior wall structure. Examples from massive external brick leaf (cladding) of the insulated brick wall are demonstrated. The thermal energy from solar radiation stored in the cladding during daytime warms the air in the ventilation gap and has a great momentary impact on the need to compensate heat losses. Due to the high thermal inertia of the brick leaf temperature of the inner surface of the leaf facing the air gap remains relatively high until early evening. This advantage is not available throughout the year, but its impact is much greater than usually believed. The knowledge from this study forms the base for the design and construction of sustainable external wall structural solutions. The location of the test buildings is showing a significant impact of solar radiation and thermal inertia to the thermal performance of external wall structures in Tampere, Finland. As the average solar radiation increases towards the south, the effect is expected to be greater in Baltic states. 4 1