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Analecta technica SzegedinensiaVol. 14. No. 2. (2020.)

Tartalom

  • Dávid Somfai ,
    Ernő Dittrich ,
    Éva Salamon-Albert ,
    Anita Dolgos-Kovács :

    We measured the daily evapotranspiration on a horizontal sub-surface flow constructed wetland in Hódmezővásárhely, Hungary. The main focus of our research was the seasonality of evapotranspiration in this CW. We measured the water balance of the CW and searched days when no precipitation, no inlet or outlet impacted on the water balance of the constructed wetland, only the evapotranspiration. had impact on the water balance. The results show that in spring the evapotranspiration rates were between 18-42,6 mm/day, in summer 12,3-42,3 mm/ day and in autumn the values were 13,6-22,7 mm/day. The highest hourly evapotranspiration was 16,3% of the daily evapotranspiration. This value was 415 % of the average, hourly hydraulic load that can significantly affects on the effluent concentration. The results also show the morning and evening condensation which has two main effects. On the other hand, the water balance of the CW is increased, which results the decrease of the concentration of wastewater.

  • Sándor Nagy :

    This publication was inspired by the study of chaining in dipolar systems. Two adjacent particles form a chain is usually decided by energy or distance criterion. This prompted the author to investigate the frequency of interaction energy between nearby chain-forming particles in the dipolar system. So what is the frequency of the two lowest energies. Does have raison d’etre of the energy-based chaining criterion? Because if so, in the frequency chart qualitative change should have see at 70-75%, compared to the lowest possible energy. No such qualitative change was observed in the computer simulations. Monte Carlo simulations were performed at many densities and dipole moments in a dipolar hard sphere system. The simulation results were theoretically interpreted using the Boltzmann distribution The theoretical relationship was generalized to a wide range of density and dipole moments by fitting three suitable parameters. The fitting was necessary due to the compressive effect of density.

  • Adebola A. Adekunle ,
    Ayokunle O. Familusi ,
    Adedayo A. Badejo ,
    Olayemi J. Adeosun ,
    Suhaib A. Arogundade :

    This study is an investigation into the characterisation of commercial activated charcoal, sawdust charcoal and rice husk charcoal as adsorbents for water treatment. The ground rice husk and waste sawdust collected, were sieved to obtain a nominal size of 1mm, washed and oven-dried for 12hours. The two materials were pyrolyzed in a furnace for 30minutes, and the chars produced were later air-dried. The three charcoals (sawdust charcoal, rice husk charcoal, and the activated charcoal purchased from the market) were all subjected to X-ray Fluorescence (XRF) analysis, Scanning Electron Microscope (SEM) analysis and Energy Dispersive X-ray (EDX) analysis in order to characterise the filter materials. The SEM analysis showed that the three materials developed more pores, which is a property of an adsorbent. Likewise, the XRF and EDX analyses confirm that all the three adsorbents possess larger proportion of Silica, Carbon and Oxygen.

  • Ildikó Kovács :

    A long-term sustainability of food consumption is in the mainstream of the current trends in the production and consumption patterns of food. A growing number of analyses question this issue nowadays. Despite several papers investigating the profile of sustainable consumers, understanding of the determinants of consumer decision-making and intention towards sustainable food consumption needed further investigation. This study investigates determinants of sustainable food and food safety on consumer behaviour among young customers in Hungary. The objective of this paper is to explore the intention factors of food safety based on sustainable consumption patterns. To gain a better insight in sustainable consumption patterns, the research process was quantitative in nature.

  • Rajab Ghabour ,
    Péter Korzenszky :

    Worldwide, governments tend to reduce the CO2 emissions, and the storage of the solar energy system is still considered the most challenging problem to solve under the current state. Mainly, in relatively cold countries, as domestic hot water or for heat process services, where the loss in the tank is huge. Any improvement in the design can achieve a higher solar yield. Since water is the usual medium for heat storage, the integration with phase change material (PCM) can store energy when there is abundant energy and release it when it is needed. In this study, we conducted a capsulated PCM soy wax 52°C in an insulated water tank filled with 5 litres of water. To estimate the appropriate number of samples and the quantity of the PCM at two temperature levels using the response surface method with non-linear correlation for the charging phase. The results show 3.16, 0.95, 0.38 first degree magnitude effect for temperature, sample numbers, and wax quantity respectively and 0.29, -0.38 second-degree magnitude effect for quantity and temperature. In addition, an illustration of each two-factors interaction contour plots.

  • Norbert Szaszák ,
    Ákos Pozsa :

    In this paper the principle of operation and preliminary laboratory measurements of a prototype of a high-efficiency electrical air heater unit is presented. Unlike conventional heaters, which apply Joule-heat formed by electrical resistance, the developed device uses thermoelectric modules for heating ambient air. Just like in case of resistance heaters, most of the heat is produced as a result of the internal ohmic resistance of the thermoelectric module (resistance heating), however, in case of appropriate air conditions our device is capable of transforming the latent heat of the air moisture into heat energy. In case of condensation mode, some of the moisture condensates on the cold side of the module while its latent heat is transferred to the hot side of the module where it heats the dried air. In this mode, the heating efficiency of the device (e.g., the ratio of the heat added to air and the consumed electricity) is over unity. Following the idea and basic equations of the operation of this device, the results of the laboratory measurements in a climate test chamber is presented.

  • József Faitli :

    Gravity solid-liquid phase separation is applied in minerals industries, waste water treatment, filtration, sewage, drinking water, ocean (water) engineering, dredging, environment and biotechnology. The healthy nation of freshwaters like Lake Balaton and River Bodrog can be maintained by regular mud dredging. The on-water pure mechanical mud thickening would be a really beneficial technology. A new automated batch settling column with vibrated rods had been developed and fundamental tests had been carried out with model materials (glass sand) and muds (Siofok, Tihany, Tokaj). A numerical evaluation protocol with spline interpolation and derivation had been developed by with simple key parameters were determined. Results can be used for the design of a new type of thickener called the rod-lamella thickener.

  • Balázs P. Szabó ,
    Zita Zakupszki ,
    Balázs Szabó :
    Behavior of the structure of different materials under static force61-68en [455.31 kB - PDF]EPA-02592-00015-0080

    The subject of rheology is the study of force-induced deformation and creep in materials, taking into account the effect of time too. The purpose of the measurements is to study time-dependent tension-deformation correlations, which include creep and tension-relaxation parameters, and viscosity. Due to the characteristic structure of biological materials, we try to introduce rheology through different materials. Our samples also include soft, semi-hard and hard materials from fish meat to human teeth. It is very clear from the obtained results that the internal structure of each material is influenced by many factors. These factors also interact with each other and they cannot be standardized in a single study.

  • Viktória Kapcsándi ,
    Martin Cserpán ,
    Erika Hanczné Lakatos :

    The aim of our research was to examine the impact of microwave radiation on the microbiological parameters of raw cow’s milk. In the measurements, our samples (raw cow’s milk) were treated at different power levels [100, 200, 300, 400, 496 (~500), and 600 W], and the effects of microwave irradiation were assessed regarding total plate count and yeast cell count. Treatment temperature was maximized in all cases (40 °C) in order to eliminate the thermal effect generated by microwaves, and hence, to justify the possible microbial inhibitor or destruction impact of the non-thermal effect of radiation. Based on the results, microwave treatment had an impact on both the total plate count and the yeast cell count as well. Treatments were performed to justify the non-thermal effect of the treatments, and significant results were obtained (p≤0.05).