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Radziszewski P.,Warsaw University of Technology | Pilat J.,Warsaw University of Technology | Plewa A.,Wydzial Budownictwa i Inzynierii Srodowiska | Krol J.,Warsaw University of Technology
Drogi i Mosty | Year: 2010

The aim of this study was to evaluate possibilities application of aggregates from glacier deposits to asphalt mixtures to be used for flexible pavement layers. Applicability of aggregate from glacier deposits was established on a basis of pavement structure analysis for traffic KR1 - KR6 category and test results of asphalt mixture stiffness modulus. Fatigue life of pavement structure in accordance to Polish guide for typical pavements was calculated together with structural design for "perpetual" pavement. Test results proved that aggregates from the glacier deposits could, indeed, be used for the structural layers in asphalt pavements. Source

The paper presents the process of shaping turbo-roundabouts. A classic road roundabout is formed around the central island in the shape of the circle. The central island of the turbo-roundabout will be created when the circle is divided into two semicircles and displaced along the axis of the roundabout by the width of the traffic lane. This shift causes that vehicles entering the interior lane, cross the centre line and are automatically situated in the exterior lane. The paper presents the central island shaping with the use of other curves, including an ellipse and the spiral of Archimedes. Moreover, the principle of creating the circulating lanes of roundabout using the spiral of Archimedes and delineating such roundabout in the terrain are described in the paper. © Instytut Badawczy Dróg i Mostów, Warszawa 2012. Source

Frak M.,Wydzial Budownictwa i Inzynierii Srodowiska | Majewski G.,Warsaw University of Life Sciences | Zawistowska K.,Warsaw University of Life Sciences
Scientific Review Engineering and Environmental Sciences | Year: 2014

Particulate matter is thought to be serious health threat on account of its easy access to respiratory tracts. Harmful health effects can be caused by particulate matter chemical composition, but also by other components, which are absorbed on its surface. Among them, there are microorganisms that potentially influence human health. The research on that influence was performed using dataset collected at Ursynów SGGW meteorological station. It was concluded, that the dominants carried by the air along with PM10 are fungi. Their quantity was subject to seasonal variation. The highest quantity of fungi and bacteria was recorded in August. In the winter period, the quantity of microorganisms significantly decreased. Negative influence of drying up of filters, containing sampled PM, on the number of active biological particles was found. This leads to the conclusion, that PM sampling for microbiological research should be done with the use of nitrocellulose filters. Source

Chalcedonite is a diatomaceous sedimentary rock, which, on account of a very small occurrence area, is included into a group of unique rocks. It occurs at De{ogonek}borzynka, Gapinin, Lubocz and Teofilów deposits, located on the Rawska Plateau in the region of Tomaszów Mazowiecki and Nowe Miasto. The deposit in Teofilów is the only documented one and it is now being exploited. The surface of this deposit is 577 437 m 2 and its geological resources were determined to be 21.587 10 6 kg (21 587.0 thousand tones). The main component of this rock is chalcedon (69.0-96.6 vol.%), however quartz, opal, iron hydroxides, pyrite, manganese compounds and clay minerals occur in small quantities. The active surface of chalcedonite is relatively small and it was determined as 3-6 m 2/g. Chalcedonite had a mesoporous structure of a significantly high pore homogeneity, and the total volume of these pores was 0.03-0.04 cm 3/g. On account of its small spatial distribution chalcedonite is a unique rock, which has multi-resource properties. It is useful for manufacturing perlite-like material, crystobalite, wollastonite and mullite. It was also found to be a valuable raw material for the production of pastes, scouring powders, grinder tools and also as good filler for the production of: paints, varnishes, enamel ware, lute and puttymaterials. Because of its mesoporous structure and due to extended outer surface of the grains, chalcedonite is utilized in water treatment technology, mostly as an effective filtration material. A high usefulness of chalcedonite bed for manganese and iron removal from water shows mostly the presence of a low height of iron removal zone in the filter, and it is also manifested by a relatively short time of introduction into effective manganese(II) removal, as well as by good hydraulic properties of the material, which enable to achieve high mass capacities of the filter and to reach long filtration cycles. Chalcedonit is a very good carrier of manganese oxides and its surface modification of leads to the creation of chemically active bed, which enables removal of manganese(II) from water with high efficiency and without the introduction process. Chalcedonite bed effective removes of ammonia nitrogen from the water in the process of nitrification and waste water treatment. Chalcedonite can be also taken into account as a sorbent for the removal of oil spills. Source

Michel M.M.,Wydzial Budownictwa i Inzynierii Srodowiska | Kiedrynska L.,Wydzial Budownictwa i Inzynierii Srodowiska
Przemysl Chemiczny | Year: 2012

Chalcedonite grains (0.8-1.25 mm) were modified with MnO2 and used for sorption of Mn2+ Ions from their aq. solns. (pH 6) under static, paradynamic and dynamic conditions. The sorption equll. was modeled by the nonlinear regression method using the Langmuir, Freundlich and Redlich-Peterson isotherm equations. The exptl. data from static batch expts. were described in the best way by the Langmuir equation, which confirmed a monolayer sorption of Mn(II) onto the sorbent surface. The exptl. data from paradynamic batch and dynamic flow expts. were described in the best way by the Redlich-Peterson and the Freundlich equations because of multilayer phys. sorption under the conditions. Max. sorption capacity was the smallest under static conditions (1.25 mglg). In paradynamic and dynamic expts. the capacity was twice or triple higher (2.21 or 4.10 mg/g, resp.). Source

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