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Analecta technica SzegedinensiaVol. 14. No. 1. (2020.)


  • Andreea-Eva Somkereki ,
    Petrișor Ioan :

    This article follows a holistic-complete approach[1] to the management of the major urban logistics projects of Imperial Timisoara. The research and studies conducted so far have been based on unilateral approaches: either exclusively historical or engineering. Research of such projects requires multi-scientific and multidisciplinary treatment angles. Our investigative optics is a managerial-holistic-complete one, which aims to integrate, besides the historical, technical / technological aspects, the architectural aspects, along with the multicultural, socio-human, ethnic, anthropological. In this sense, the strategic references of urban essence are related to the potential of Timisoara city and its ability to carry out such projects, in the contexts specific to the different periods of its logistic development. The multitude of researched data sources, information and documents enables us to innovate the analytical approach of major urban logistics projects, using the logic of public management, in a holistic-complete, integrative vision. This research is part of a comprehensive study on general urban public management. We are convinced that such research, in such a way, will contribute substantially to a deeper understanding of Timisoara's contribution to its own Europeanization and the region it was part of, the Imperial Historical Banat.

  • Babatunde Olamide Omiyale ,
    Peter Kayode Farayibi :
    Additive manufacturing in the oil and gas industries9-18en [565.62 kB - PDF]EPA-02592-00014-0020

    Additive manufacturing (AM), also known as 3D printing, is a process for creating prototypes and functional components achieved by consolidation of material layer upon layer. Applications of AM technologies have been witnessed in the healthcare, automotive, architecture, power generation, electronics and aviation industries. Some of the main benefits of AM include effective material utilisation, new design possibilities, improved functionality of the products and flexible production. The opportunities for the applications of additive manufacturing in the oil and gas industries are only just being explored. In this study, a review of the potential opportunities of AM technologies in oil and gas industries was reported. The adoption of the AM technologies necessitated the need for a rethink on design for manufacture and assembly of oil and gas component parts such as high-tech end burners, metal fuel nozzles, and submersible pump components amongst others. The possibility of employing AM technologies on-site for the production of spare parts for replacement of damage components in oil and gas equipment and facilities is commendable, as this brings about reduction in production downtime and replacement cost. The future of AM in the oil and gas industries is highly promising, however before AM can actualize its full-fledged potentials in these industries, further research is required in the area of new materials development and processing, improved surface finish of AM fabricated parts, enhanced fabrication speed and parametric optimisation to improve the mechanical properties of the fabricated components.

  • Rita Tury ,
    Szilárd Tóth ,
    Réka Láposi ,
    László Fodor :

    The experiments were set up in large parcels at the Fleischmann Rudolf Research Institute of Eszterházy Károly University located in Kompolt. We carried out measurements by using a Penetronik penetrometer (electrical soil cone penetrometer) at the experimental site, where brown grassland soil as well as clay washed brown forest soil are the typical soil types. The device used primarily serves to investigate the physical and water management properties of soils suitable for agricultural cultivation. The instrument is a hand-operated tool for registering soil mechanical resistance in Newtons (0-1000 N) and also the moisture content of the topsoil (%) at the same time. The recording of the location of the measurement is made by the built-in GPS, and the results of the measurements are saved to the SD card of the device. The device’s data acquisition unit allows direct reading of measurement results, serial measurements and computer processing of results (0-70 cm). Taking our objectives into consideration, we defined the location of measuring points with various numbers according to the properties of the examined fields. Besides designating measuring points at a distance of 0, 5, 10, 15, 20 and 30 m from the edge of the fields, we designated two more in the middle of each field in all cases. The examined crop species included sand oats (Avena strigosa), baltacim (Onobrychis viciifolia) as well as common vetch (Vicia sativa L.) with oats as a companion crop. Summing up the measurement results, we have made the following statements: Low soil resistance (127-131 N) was experienced after soil loosening and oat-vetch with higher, well-preserved soil moisture content observed at each level, where the 50% moisture content of the soil started at the layer of 27 cm depth. Moderate soil resistance values (150-168 N) were manifested in the case of soil tillage with loosening and ploughing after sand oats. In this case, the 50 % soil moisture content was observed at the layer of 38 cm depth. Higher soil resistance values were found (171-196 N) in the case of 2 and 3-year-old crops of baltacim, respectively, where the 50 % soil moisture content was recorded from the layer of 58 cm depth. Based on the results, we consider it important to develop and improve soil tillage systems.

  • István Bodnár :
    Simulation of acacia gasification process24-33en [618.63 kB - PDF]EPA-02592-00014-0040

    This electronic document presents the thermokinetical modelling of the gasification process done on acacia-tree with variable operating conditions and different humidity levels. Gasification does not produce flue gas, but due to imperfect burning, synthesis gas appears which is rich in flammable components (CO2 and H2). The chemical structure of this gas depends on the components of the fuel and the humidity level, but greatly affected by the technological parameters too, such as pressure and temperature, as well as the air-ratio. The study shows the change in the amount of the fuel and the reaction efficiency, caused by varying gasification temperature and pressure. Rising temperature results in improved efficiency, while higher pressure worsens reaction efficiency. However, at higher temperature intervals, the effect of the pressure is neglectable.

  • Ivana Nikolić ,
    Ljubica Dokić ,
    Aleksandar Takači ,
    Zita ©ereą ,
    Dragana ©oronja-Simović ,
    Nikola Maravić :

    The traditional hummus spread is obtained of cooked and grinded chickpeas, blended with susame paste (tahini), olive oil, lemon juice and spices. Hummus spread is a rich source of dietary fibers, polyunsaturated fatty acids, vitamins A, E and C, folate, minerals Mg, K and Fe. During production of such kind of spreadable food product, many factors can have influence on product behavior trough the all phases of production and to the final product quality. In this work, the influence of different technological factors on rheological, textural and sensory properties of hummus spreads made by certain recipes were examined, in the aim to achieve the maximum quality of final product. The way of preparation of raw materials, the composition of the spreads and the amount of water phase have been varied in the aim to define optimal rheological and textural parameters, to increase the production efficiency and in order to obtain desired sensory properties of final spread product.

  • Klára Czakó-Vér ,
    Dávid Somfai ,
    Erzsébet Suhajda ,
    Csilla Sipeky ,
    Gyula Árvay ,
    Anita Dolgosné Kovács ,
    Ernő Dittrich :

    Aim of this paper is to examine the effect of spiked copper (Cu), nickel (Ni) and lead (Pb) metal salts on the dehydrogenase (oxydo-reductase) and phosphatase (hydrolase) enzyme activities in a characteristic Hungarian soil, the pseudomycelliar chernozem. Pot-experiment was performed with a soil, originating from a spot of the Hungarian soil-information-monitoring (TIM) system of Bicserd. The added metal salts were used in water soluble forms and incorporated uniformly to the soil. Soils were treated with increasing metal concentrations to give the following metal amounts: 0, 50, 200, and 800 kg.ha-1. Enzyme activities of the soil were analysed at the 0th, 7 th, 14 th, and 28th days after the metal addition. The laboratory model-experiment has been set up in three replicates. Effects of metal salts were largely dependent on the chemical and physical properties of pseudomycelliar chernozem soil, the applied heavy metal-types, the doses of used metals and the elapsed time after the pollution. Considering the different metals, the copper prowed to be the most toxic one on the studied enzyme activities, whereas the lead induced those. By comparison with copper the nickel affected a smaller decrease in the soil microbial activity. The dehydrogenase, oxydo-reductase enzyme was found to be more sensitive parameter in comparison with the phosphatase, hydrolase enzyme among the studied condition. Studied enzymes and used methods are suggested, as fast and rather reliable tools for estimating the soil-resilience capacities at heavy metal pollution.

  • Peter Bencs ,
    Mohammed Al-Ktranee ,
    Károly Marcell Mészáros :
    Effects of solar panels on electrical networks50-60en [849.75 kB - PDF]EPA-02592-00014-0070

    Today, the increasing use of solar energy contributes to the EU's energy policies. Increasing use of renewable energy sources reduces pollutant emissions, dependence on fossil fuels and improves air quality. Globally, installed photovoltaic capacity has reached 400 GW by the end of 2017, and is projected to reach 4,500 GW by 2050. In the context of this research, we would like to present a detailed presentation of the possibilities and effects of integrating solar systems into electricity networks. The integration of renewable energies into networks is of paramount importance to researchers because of current energy demand and the depletion of fossil fuel reserves and environmental impacts. In this study, we highlight the effects of solar network integration on both the solar system and the public utility service. We also report on the opportunities and impacts of integration in Hungary in connection with our research. Today, solar panels are the cornerstone of sustainable development.

  • Betti Bolló :

    Treatment of municipal effluents has long been a challenge for modern technologies combining high effectiveness of degradation of pollutants with low costs of the process. Hydrodynamic cavitation is a promising application in wastewater treatment due to its simple reactor design. In this work, for a system available in the laboratory a hydrodynamic reactor is designed based on literature recommendations. On the designed Venturi tube, two-dimensional numerical simulations were investigated by the means of CFD computations using the commercial software package, Ansys Fluent. The resulting cavitation bubbles were analysed at different inlet pressures.

  • Dávid Faragó ,
    Péter Bencs :
    Measurement of turbulence properties67-75en [736.29 kB - PDF]EPA-02592-00014-0090

    The aim of the research is to investigate anisotropic turbulence intensities, id est to investigate the distribution of Reynolds stresses and energy spectra in a square cross-section channel, downstream of a semi-active jet turbulence grid generating anisotropic turbulent airflow. In addition to the semi-active jet turbulence grid, another type of turbulence grid was developed and experimentally investigated. This grid contains vertical, flexible strips of aluminum (in this case, there are no perpendicular (horizontal) grid elements), which vibrate at a frequency depending on the velocity of the main airflow. Besides the investigation of the velocity- and turbulence intensity distributions, another main objective of the research is to measure the von Kármán energy spectrum when the turbulence cannot be considered isotropic. This aspiration of ours is justified by the knowledge gap present in the literature in this specific field. Monin has carried out a theoretical study to extend and generalize the von Kármán – Howarth isotropic principal stress equation to the anisotropic regime. The proposed new experimental work aims to provide a solid experimental background for verifying and validating the physical correctness of the Monin equation, which may result in a new theoretical understanding and perception of the major issues and the nature of anisotropic turbulence. Since the anisotropic energy spectra are expected to exhibit different characteristics from the isotropic Kolmogorov spectra, these new experimental results may contribute to the development of new anisotropic and engineering turbulence models that can be used in industrial applications.

  • Klára Czakó-Vér ,
    Dávid Somfai ,
    Erzsébet Suhajda ,
    Márk Strasszer ,
    Gyula Árvay ,
    Anita Dolgosné Kovács ,
    Ernő Dittrich :
    The application of biogas fermentation digestate as soil fertilizer76-81en [317.02 kB - PDF]EPA-02592-00014-0100

    As organic manure is becoming less available, using different materials as soil fertilizers and the application of the inorganic fertilizers raises many questions. Therefore, it is increasingly important to use compost and biogas digestate to improve soil quality. The activity of the microbial communities ensures the fertility of the soil. One of the most important enzymes is dehydrogenase. This enzyme group catalyses the hydrogen transfer in the process of biological oxidation. Our aim was to examine the effect of biogas digestate on dehydrogenase enzyme activity (DHA) in 3 different types of soil. Hungarian standard method was used to evaluate DHA. The applied biogas digestate was obtained from the Kaposvár Sugar Factory of Hungarian Sugar Ltd. The dose is equal to 16,7 m3ha-1 and 533 kg organic matterha-1. The treatment was performed in three different groups of soil: brown forest soil, calcereous chernozem and carbonate meadow soil. The results showed an increase in DHA in all types of soil. DHA values were the highest in case of the carbonate meadow soil, specifically 0.337 mg formazan/1 g soil/24 h immediately after the treatment and 0.410 after 28 days. A critical aspect to consider during the construction of biogas plants is the soil protection agency’s ban on using soil fertilizers during the winter months. Analysis carried out according to the protocol of sewage sludge examination revealed that biofermentate produced during biogas generation does not contain any environmentally harmful components. After the elaboration of a soil protection plan, the recommended way to apply biogas digestate to arable land is via injectors.

  • Sándor Bodzás :

    The aim of this study is the comparative finite element analysis of the tooth roots of one tooth on worm-wheels having different geometries. Designing of various cylindrical worm gear drives is essential for the study where all of the input parameters are the same, only the number of thread on the worm is modified. Due to this modification the shape of the worm-wheels is different that is why dissimilar mechanical parameters will be received by the same load force. The creation of the CAD models is also important for the analysis.

  • Mücahit Varlı ,
    Elif Gülin Ertuğral ,
    Zoltán Jákói ,
    Cecilia Hodúr ,
    Sándor Beszédes :

    A significant representative of the third generation of raw materials is waste containing hemicellulose. Agriculture and the food industry generate a great deal of this type of waste, which has many potential opportunities for processing. Our research group investigated the pre-treatments for the enzymatic saccharification of the cellulose content of the two fractions of corn cob meal. Microwave energy communication was performed in both acidic and alkaline media. It was found that the pH of the medium influences the amount of reducing sugars, but to an almost equal extent. The yield is also significantly dependent on the starting material and the concentration of the suspension.

  • Mohammed Alktranee ,
    Péter Bencs :
    Overview of the hybrid solar system100-108en [512.37 kB - PDF]EPA-02592-00014-0130

    This paper investigates the uses of solar energy systems in various applications to define the most appropriate system that has highly efficient and reliable. Mostof the urban even rural areas that suffer from lack of continuous power supplies it prefersto depend on hybrid systems like solar/wind systems, solar/geothermal system,and solar/diesel-battery systems. Investigation indicates that hybrid systems could meet the required loads in different proportions depending on the operating conditions and components of the hybrid system compare with the separate system but has complexity regarding their components of the system with the high initial cost. Moreover, utilize hybrid solar/thermal system is more sufficient than had systems that mentioned as a result of the improvements at his parts to increase the overall efficiency by using phase change material (PCM), nanofluid or a mix of PCM -nanofluid as cooling the photovoltaic (PV) panel to keep the efficiency of the solar cells and increase thermal energy. Thus, hybrid solar/thermal systems had proven effective to meet the requiredloads of electric energy and good capacity to provide thermal energy simultaneously without toxic emissions with a negligible complexity of its components

  • Csaba Leitol ,
    Alexandra Győrfi ,
    Tibor Kiss :

    Significant development has taken place in the field of waste management recently in the preparation of the energetic exploitation of recyclable, non-hazardous municipal solid waste. With mechanical-biological waste treatment, 35-40% of the weight of this waste can be made appropriate for energetic exploitation, mainly for co-incineration in cement factories and power plants. The recoverability of waste derived fuel produced in mechanical-biological waste treatment plants highly depends on the burning and combustion technological properties of the mixture, and on its compounds influencing burning and different emissions. Waste recovery facilities do not take over fuel below a specific calorific value and over a given heavy metal, halogen and pollutant content. In our research we were looking for correlations in the particle size, calorific value, moisture-, ash- and heavy metal content of waste derived fuel. On the basis of the measurement results, the connection between the particle size fractions and the fuel properties can clearly be stated. The fractions of smaller particle size have higher moisture-, ash- and heavy metal content, while the fractions of bigger particle size have higher calorific value.

  • Anita Tolnay ,
    Arijit Nath ,
    Andras Koris :
    Challanges of sustainable food technology - A review118-129en [454.75 kB - PDF]EPA-02592-00014-0150

    Over the last decades due to rapid development of human civilization along with revolution in technology, some burning issues about generation of environmental contaminant, management of by-products from technologies, high consumption of natural resources and conservation of natural resources have been dramatically raised. Without any contradiction, impacts in overall ecosystem as well as human civilization have negative effects. These evoked lots of scientific and industrial researches, and implemented several stricter environmental legislations on the development of sustainable ecosystem. Thus, sustainability has become an emerging topic all over the world, as evidenced by the growing body of scientific publications in the last 20 years with one order of magnitude increase since the start of the new century. The study attempts to perform a review of the sustainable development from the food industry’s perspective. At present, the agro-food sector produces high amount of carbon dioxide, food waste, packaging waste, wastewater, etc. and it is still consuming a lot of water, land, oxygen and energy. Furthermore, taken into consideration the increasing number of the world’s population, there has been an enhancing interest experienced towards sustainable development among food manufacturers in the last decades. The article highlights the paramount areas of sustainable production, which offers new directions towards the increasing number of human beings for the future survival. The paper also gives an overview of the main perspectives contra constraints of sustainable food production, offers innovative food products from sustainable food waste and by-product, and focuses on the growing importance of sustainable food production in life cycle assessment methodology as well.

  • Ernő Gyimes ,
    Dóra Csercsics ,
    Zoltán Magyar :
    Effect of short term storage on wheat quality parameters130-141en [311.26 kB - PDF]EPA-02592-00014-0160

    Eleven samples of registered wheat varieties of bread with diverse technological qualities were used in this study. The samples were devided into two groups. The first group including all the 11 variety were stored for 3 months, while the second group of the samples were stored for 9 months at an ambient temperature. The results of quality evaluation showed that 5 soft wheat varieties (GK Csongrád, GK Garaboly, GK Hattyú, GK Holló, GK Nap) and 6 hard wheat varieties (GK Ati, GK Békés, GK Élet, GK Kalász, GK Petúr, GK Verecke) were involved in the study. Further, the flour yield, the gluten index and the water absorbance capacity has significantly decreased after 9 months storage time when compared to 3 months storage interval.

  • Laura Haranghy ,
    Réka Dobozi ,
    Zoltán Jákói ,
    Sándor Beszédes :

    Nowadays, the development of rapid and non-destructive measurement methods have high importance. The dielectric measurement is a promising technique to detect the chemical and physicho-chemical change of different materials. The dielectric behavior of pure water is widely investigated for decades, but there is very few information available related to the dielectric parameters of wastewater. Our study aims to investigate the applicability of dielectric measurements for the detection of the change of biodegradability of wastewater. In the experiments the change of organic matter solubility and biodegradability of sugar beet processing wastewater, meat processing wastewater, dairy industry wastewater and municipal wastewater was examined. Our results show that dielectric constant - measured at the frequency of 2400 MHz - has a strong linear correlation with the soluble chemical oxygen demand (SCOD), which makes possible the fast detection of disintegration efficiency of different wastewater and sludge treatment processes, or the organic matter removal efficiency of wastewater purification technologies. Furthermore, our results verified that the change of aerobic biodegradability (expressed in BOD5/SCOD ratio) show also good linear correlation with the dielectric constant. These preliminary results enable to develop a dielectric behavior based detection method for the estimation of the efficiency of wastewater treatment processes.