Browse

You are looking at 61 - 70 of 3,644 items for :

  • Materials and Applied Sciences x
  • Refine by Access: Content accessible to me x
Clear All
Pollack Periodica
Authors: Orest Voznyak, Olena Savchenko, Nadiia Spodyniuk, Iryna Sukholova, Mariana Kasynets, and Oleksandr Dovbush

Abstract

This article discusses the topical issue of improving the distribution of air in the premise due to application of the all type rectangular air streams: flat, axisymmetric and rectangular ones. The purpose of the article is research of the all types rectangular air streams, analytical dependencies obtaining for determination of the air velocity attenuation coefficient, aerodynamic local resistance coefficient and noise level from the ratio of slit length to its height; optimization of the inflow slit side's ratio. It has been established that increase of the inflow slit sides ratio results in the air velocity attenuation coefficient decrease and results in increase of the noise level and resistance coefficient of the rectangular slit. The optimal ratio of the sides of a rectangular slit is determined by the combination of aerodynamics and energetics, as well as of the sound power level.

Full access

Abstract

This article presents an analytical and numerical assessment of load-bearing capacity of a beam-to-column joint. Two possibilities have been examined: a joint reinforced with a fastened haunch on the side of a compressed flange of a beam and a joint with no reinforcement. The load-bearing capacity and rotational stiffness of joint and has been calculated. Distribution of stresses and deformations in particular components of the joint has been determined. The results of analytical and numerical calculations have been compared, proving that the load-bearing capacity of the joint calculated on the basis of analytical approach provides safer results (for a reinforced and non-reinforced joint), and however in certain cases it may lead to oversizing of the connection.

Full access

Abstract

Wind generation is regarded by many as the future of renewable energy source, but the difficulty of recycling end-of-life wind turbine components could create another kind of environmental pollution. Either landfill or incineration of end-of-life wind turbine components will cause environmental hazards. However, the current recycling technology is immature and economical. Make clean energy ‘cleaner’! The recycling of end-of-life wind turbine rotor hub and blades has become a new goal and task for architects and designers. This article uses a real project reconstructed by end-of-life wind turbine components to demonstrate the positive role of spatial narrative in achieving low-carbon and sustainable design.

Open access

Abstract

The floodplains of the Tisza River, stretching across the eastern part of Hungary, are often affected by riverine and inland excess water flooding and draught. This paper investigates a possible solution to this problem utilizing the water retention capabilities of old floodplains. In this study, the effect of the position of the inlet structures of a floodplain, near Csongrád town, was examined with HEC-RAS 1D-2D coupled model. Based on the results, the rules of the deep floodplain selection were determined. On the extended model, the possibilities of a deep floodplain storage area chain have been explored. According to the estimate, more than 2.36 km3 potential storage capacity is available along the Hungarian section of the Tisza River.

Open access

Abstract

In order to develop and enhance the quality of life in Tunisian urban spaces, the integration of street furniture became a new challenge for urban designers to use new methods and techniques to combine functionality and aesthetics into their design. The main objective of this paper is to focus on the analysis of the street furniture user’s needs in urban spaces to understand and discuss the requirements that should be considered while designing.

Open access

Abstract

Nature-based solutions use a holistic viewpoint to address social challenges while providing environmental, social and economic benefits simultaneously. The Victoria Quay is a historical space with complex social and environmental issues. This study uses an investigation-oriented method to explore the re-planning strategies. The environmental problems are addressed by extending the green infrastructure into the site to recover the ecological corridor and alleviate flooding risks. The originally single land-use type is changed, and several historical buildings are transformed into landmarks to improve the connection with city center by linking the ‘golden route’. All the proposed measures tried to reactivate the various relationships rather than merely renew the Victoria Quay.

Open access

Abstract

Fungal disease resistant (PIWI) interspecific grape varieties are playing an important role as an alternative for organic wine production. Organic (bio) wines are demanded by numerous conscious consumers around the globe. They choose this kind of wines predominantly because of the absence of synthetic pesticides, fertilisers and sustainable agriculture. Resistant grape growing moreover results in additional environmental and health benefits. Nero and Bianca are among Hungary's most promising interspecific grape cultivars gaining international interest recently, there are, however, limited vitivinicultural knowledge on them. Our aim was to examine the flavonoid and anthocyanin composition for both interspecific varieties during different harvest times in two consecutive vintages. The date of harvest and vintage played a significant effect on grape and wine quality.

Open access

Abstract

Proteases hold an important position in today's world commercial enzyme market. Among various microbial producer genera, Bacillus is leading the commercial protease production. However, industry is still actively looking for new microbial protease producers with distinctive properties. Therefore, this study was undertaken for the evaluation of protease production by Bacillus megaterium DSM 32 strain in terms of its protease productivity, calculation of various production kinetics, partial characterisation of the enzyme, and modelling the protease production process. As results, the highest protease activity, specific cellular protease production rate, and protease productivity were calculated as 255.42 U mL−1, 36.2514 U g−1, and 16.1313 U mL−1 h−1, respectively, in shake flask fermentations. Partial characterisation studies showed that the enzyme has 45 °C and pH 8 as optimum working conditions, and its activity increased by 24% with the addition of 5 mM Mn+2 to the reaction medium. Additionally, the enzyme showed high stability and kept almost full activity in a cell-free medium for 20 days at 4 °C. Furthermore, modified Gompertz model provided the best fit in describing protease production with the lowest error and high fit values.

Full access

Abstract

Poultry processing industry produces large quantities of by products (skin, bone, and feather) that contain significant amounts of protein. The source of gelatine is of great concern for some societies including Muslims, Hindus, and Jews as gelatine is mostly obtained from porcine sources. In the present study, gelatine was obtained from chicken skin and some quality and functional features were evaluated in comparison with commercial gelatines from porcine, bovine, and piscine sources. Chicken skin gelatine formed stable foams by a foaming stability of 83.3% as well as high emulsion activity of 72.8 m2 g−1 compared to commercial gelatines. On the other hand, gel strength and viscosity of chicken skin gelatine were 307 g and 2.5 cP, respectively, and significantly lower than that of commercial gelatines due to high content of impurities. The results concluded that chicken skin may be used in gelatine manufacturing upon efficient removal of fat, which was the most abundant component in the dry matter of chicken skin.

Full access

Abstract

Based on the theory of space syntax, this research conducts a quantitative study on the four stages of Zhanjiang urban spatial organization system, and draws the urban evolution process. This study found that the development strategy of different periods has a huge impact on the urban development. It determines the structural basis of the original urban space and creates strong development inertia. According to these research results, it can provide an effective theoretical reference for the future spatial expansion of the city.

Open access