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Abstract

Contemporary architectural transparency, understood as the optical property of the construction material, is constantly being redefined and, over the last two decades, new design trends have developed. These trends are the result of: (i) dynamic technological progress; (ii) advancement in the field of materials science; (iii) changes in the attitude of clients and users. Transparency is no longer limited to specific functions (e.g. illumination of the interior) but has become a tool of formal expression itself. This paper defines most recent trends, which are divided into two main types: (i) optical-perceptual – relying on phenomenal effects, (ii) geometrical – that differentiate the large group of spatial transformations developed from what was initially flat planar façade.

Abstract

The present work examines the influence of the leaching conditions on the release of various chemical elements from a cementitious material obtained by solidification of an industrial waste rejection of Algeria. Toxicity Characteristic Leaching Procedure (TCLP), X-ray diffraction (XRD) and Scanning electron microscopy coupled with energy dispersive X-ray microanalysis SEM-EDX analyses were employed to characterize the waste and the stabilized/solidified materials. Than several formulations were prepared with different percent of waste ranging from 0 % to 30 %. To evaluate the influence of leaching conditions on the release of chemical ions (Zn2+, Pb2+, Cl-, Mg2+, Ca2+, Na+, K+ and SO4 2−) contained in the stabilized and solidified materials, the Acid Neutralization Capacity (ANC), the Pore Water (PW) and Monolith Leaching Tests (MLT) have been carried out. The leaching tests (ANC, PW and MLT) have shown a low metal leachability. However, the lowest released amount was observed for the MLT.

Abstract

The nineteenth century was a period of ground-breaking events in the history of humanity relating to the industrial revolution, scientific discoveries, knowledge development and social changes. It was also a time when new types of commercial buildings were being formed and transformations of those that had existed for centuries were taking place. The aim of this article is to present the problems of the Central Market Hall in Budapest by Samu Pecz and compare its architectural solutions with selected nineteenth-century constructions serving the same purpose elsewhere in Europe.

Abstract

Carbon dioxide (CO2) injury is one of the key cause affecting the sales of fresh-cut apples during the sales period. The method to warn the time till occurring CO2 injury would be convenient for businesses and consumers, but so far, no one has paid attention. This research aimed to study the change rule of the mechanism of carbon dioxide injury of fresh-cut apples treated with high CO2 concentration. The experiment was conducted at 5, 15, 25 and 35°C for 4 days. Every twelve hours, the fresh-cut apple was analyzed by measuring the changes of firmness, soluble solids concentration, browning index and sensory evaluation. The results showed that sensory scores, firmness and soluble solids concentration decreased over time, while the browning index of freshly cut apple increased rapidly with time. Based on the dynamic model of the browning index, with the CO2 Injury warning model of ready-to-eat apples treated with high CO2 concentration was determined.

Abstract

In this study, 1 wt.% Pd/Al2O3 sphere catalysts were prepared using the wet-impregnation (WI) and deposition-precipitation (DP) method using palladium chloride and tetraamminepalladium (II) nitrate as salt precursors. All catalysts were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier-transform infrared (FTIR) spectroscopy. The catalytic activity in toluene oxidation under gas-phase conditions was measured. The obtained results showed that metal dispersion and catalytic activity were strongly dependent on the salt precursor and method of catalyst preparation. The use of tetraamminepalladium (II) nitrate as the precursor presented smaller particle size, an enhanced dispersion and higher specific surface area. Moreover, the catalyst prepared with this precursor also showed higher catalytic activity than that prepared with palladium chloride. At 1 wt.% Pd loading, complete oxidation of toluene was achieved at 250°C. However, there was only approximately 80–90% efficient at the same temperature when the catalyst was prepared with palladium chloride as the precursor.

Abstract

The paper presents results of the research focused on the characterization of two types of coatings – WC–FeCrAl and WC–WB–Co. The properties of the WC–FeCrAl coating (Co and Ni free) were compared against the WC–WB–Co coating to see if it could be used as an environmentally more suitable substitute for conventional Co and Ni containing powders. The coatings were applied by HVOF technology. The influence of thermal cyclic stress on the hardness, adhesion of coatings and their corrosion resistance was determined. A change in the phase composition of coatings after thermal cyclic loading was also determined.

Abstract

This study assessed the physicochemical and sensory properties of ‘probiotic’ drink from blends of milk analogues from African yam bean, soybean and coconut. Milk analogues were blended at ratios of 1:1:1, 3:1:1 and 5:1:1 (African yam bean: soybean: coconut) as samples A, B and C respectively. These samples were fermented for 24 h at 43°C using Lactobacillus delbrueckii. The results showed that the fermented milk analogue of ratio 1:1:1 was the most acceptable in terms of sensory parameters. The pH of the milk analogues ranged from 5.07 to 5.85. The sample B1 (fermented (1:1:1) African yam bean: soybean: coconut) had a crude protein of 2.38%, potassium of 80.13 mg/100g, phytate of 2.85 mg/100g and saponin was 0.19 mg/100g. The study concluded that the sample with equal ratio of African yam bean, soybean and coconut adjudged the most acceptable by tasters.

Abstract

The objective of this research was to assess energy independent and develop a model of closed system production process of cocoa butter and cocoa powder. Mass balance analysis and potential energy assessment of byproducts were used to develop the closed system of cacao processing industry. The results showed that cacao industry with 4,500 kg of cacao capacity per day has the potential energy of 14,561,290 k cal per day derived from the pod husk and bean shells. This potential energy meets the energy needs for the production process. This study explained that the cacao industry can be developed to be an energy independent industry by using the by-products for energy source.

Abstract

Earlier we determined the colostrum and milk composition of cows after single- and twin-calving as well as the changes in the composition as a function of postpartum time. It was established that the dry matter, protein, whey protein, and immunoglobulin-G (IgG) content of the first-milked colostrum immediately after calving was significantly higher with twin-calving cows than with single-calving animals. As regards the other components, there were no significant differences among the animals. During the last years, we managed to collect the first-milked colostrum from five cattle after triplet-calving. The composition of these samples were determined by the methods we used earlier at twin-calving animals, and the results were compared to the colostrum composition of single- and twin-calving animals. It was found that although as an effect of triplet-calving the protein and IgG content of colostrum increased, the difference was not significant between twin- and triplet-calving animals. We are aware that others have not reported data from the point of view of the colostrum composition of twin-calving, and in the case of tripletcalving our results are unique in the world. In our publication, we report on the results of our investigations.

Abstract

This article presents a method for the quick assessment of the safety of the road on an active landslide on the Just mountain at Tęgoborze using the landslide hazard ratio of landslide movements. The hazard indicator for landslide traffic has been defined as the quotient of the largest displacements obtained from measurements using a terrestrial laser scanner to the largest displacement obtained from a numerical model of the worst geotechnical conditions and an unstable landslide. The application of this indicator was presented on the example of national road No. 75 along the section of the road in km from 51 + 900 to 52 + 700 at the location of the Just mountain at Tęgoborze in the south of Poland. The road is located on an active landslide and has a lot of traffic. The measurements were conducted with the RIEGL. VZ400 terrestrial laser scanner from 2012 to 2016. As a result of the measurements performed with a terrestrial laser scanner, a cloud of 3D points was obtained. Differential models of subsequent measurements were constructed and compared to the first base measurements. The results of 3D differential models obtained from terrestrial laser scanner measurements were compared with results obtained from 3D numerical modelling. Numerical calculations were conducted assuming the worst geotechnical conditions. The model of the landslide was fully saturated. A numerical simulation computed using the finite element method (FEM) in the MIDAS GTS program was applied. A result of the safety factor F = 0.8 (i.e. an unstable landslide) was obtained. In order to estimate the hazard, the values of the landslide hazard indicator were determined for each date using the measurements conducted with the laser scanner.