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Abstract

This study aimed to evaluate the efficiency of various mash acidification techniques in alcoholic fermentation for the production of apple spirit. Lachancea thermotolerans and Lactiplantibacillus plantarum strains were selected to conduct pre-fermentative acidification of the mash alongside a conventional chemical acidification approach. The results confirm that L. thermotolerans and L. plantarum possess acidifying potential and can serve as effective biotools for the protection of apple mash during fermentation. Through their outstanding lactic acid production (1.05–1.26 g L−1), they were able to reduce the pH of the mash by 0.29–0.40 pH units. Moreover, the sequential fermentation of these strains with Saccharomyces cerevisiae is a powerful strategy to modulate the aroma profile of apple spirits. Spirits were characterised by an enhanced ester profile with particularly increased ethyl lactate concentrations.

Open access

Az erdőállományok talajvíz utánpótlódásra gyakorolt hatásának vizsgálata kecskemét-ménteleki mintaterületen

Investigation of the impact of forest stands on groundwater recharge in the Kecskemét-Méntelek study area

Agrokémia és Talajtan
Authors:
András Szabó
,
Zoltán Gribovszki
,
Péter Kalicz
,
Ján Szolgay
,
Zsolt Gácsi
, and
Bence Bolla

Az Alföldet, azon belül is különösen a Homokhátságot érintő talajvízszint süllyedés, súlyos ökológiai és gazdasági következményekkel is járó problémakör. A jelenség hátterében álló lehetséges okokkal kapcsolatban több évtizede zajlik kutatómunka, ugyanakkor ezek relatív súlyának meghatározása a mai napig tudományos vita tárgyát képezi.

Több szerző is kiemeli az erdőtelepítések talajvízszint csökkentő hatásának fontosságát. Ez a hatás két módon, a vegetáció vízfelvétele, illetve a csapadékból történő utánpótlódás csökkentése (intercepció, talajnedvesség felvétel) által jelentkezhet. Ezen mechanizmusok működését vizsgáltuk meg egy akác (Robinia pseudoacacia) és egy fekete fenyő (Pinus nigra) állomány esetében a Homokhátságon, Kecskemét-Ménteleken kialakított mintaterületünkön, 90, 150 és 200 cm-es mélységben, nagy időbeli felbontással mért talajnedvesség, illetve talajvíz adatokra alapozva.

Az adatok alapján feltételezhető, hogy a talajvízből nem történik közvetlen, vagy közvetett vízfelvétel, aminek oka vélhetően a gyökérzóna és a talajvíz közti igen jelentős horizontális távolság. A talajnedvesség esetében a sekélyebb rétegekben egyértelműen jelentkezik az erdőállományok szezonális szárító hatása. Ugyanakkor a mélyebb rétegek talajnedvesség adatai alapján kijelenthető, hogy a csapadékból történő talajvíz visszatöltődésre leginkább az akác állomány alatt van elméleti lehetőség. A látszólagos ellentmondás feltételezhetően a gyökérzet által kialakított makropórusok hatásával magyarázható. Ezt támasztja alá az akác és fekete fenyő állományok közti igen jelentős eltérés is.

Következtetésünk, hogy az erdőállományok lokálisan jelentősen eltérő hatást gyakorolhatnak a talajvízszintre. Ezért a lezajló folyamatok hátterét, általános jellegű megállapítások helyett, az adott hidrológiai rendszer több elemét vizsgáló monitoring adataira alapozva lehetséges csak felderíteni.

Open access

Abstract

The inorganic scaling in wells is a common problem faced by mining companies. At present, the use of protective coatings for tubing as a measure to prevent or reduce the formation of inorganic scale deposits on pipe walls has not been fully studied. To use protective coatings as a measure to counteract the deposition of inorganic salts, it is necessary to develop a method that allows assessing the ability of coatings, as well as polymer and metal materials, to prevent the formation of inorganic scale deposits on the inner surface of pipes.

The article proposes a method for assessing the ability of protective coatings to resist the inorganic scaling on the inner surface of tubing. The proposed assessment method allows to make an informed decision on the advisability of using internal protective coatings of tubing to prevent (or reduce) the formation of inorganic scale deposits. The authors consider design features of a test bench for assessing the resistance of coatings to inorganic scale deposits, which allows to simulate the conditions for the formation of scale deposits that are as close as possible to the real conditions of oil production facilities. The article presents the results of bench tests of nine coating samples, two polymer samples and one sample made of St 40G2 steel. To assess the effectiveness of using tubing with an internal anti-corrosion coating as a measure to combat scale deposits, additional research is required to assess the possibility of complex use of coatings in conjunction with other methods of preventing processes of inorganic scaling. Thus, the authors developed the Bench for assessing the resistance of protective coatings of tubing to inorganic scale deposits. A dynamic testing technique is proposed to evaluate the resistance of protective coatings to inorganic scale deposits. Based on the presented results, conclusions were drawn about the possibility of using protective coatings on tubing as a measure to prevent the formation of inorganic scale deposits on the inner surface of the tubing.

Open access

Abstract

The work focuses in architectural dimension of urban form, by confronting the plans of three neighborhoods in Prishtina that represent potentially three main urban paradigms of the last decades in city's urban transformation. The study aims to unfold the main elements, confront them, and expose to possible transformation. The work progressively decomposes each case into basic components and deductively to their minimal unit.

The research, through interpretation and graphic illustrations, analyzes the three plans by layers: basic elements and their relational modalities, urban matrix, open space character and composing minimal units. The process will identify the main components, and their generic potentiality to be considered as future inputs in city's development.

Open access
Pollack Periodica
Authors:
Naghm Mahdi Saidik Al-jamaily
,
Huda M. Atiea
,
Qusay A. Jabal
,
Waseem H. Mahdi
, and
Laith Abdulrasool Alasadi

Abstract

Even though concrete structures are safer than steel structures in terms of fire resistance, the risk exists in concrete structures by spalling or exploding, especially in high-strength concrete. This study aims to produce a particular type of concrete using waste ceramics as fine aggregate and waste glass as coarse aggregate and compare data with normal aggregate concrete. Studies show that using waste ceramic and glass increases the fire resistance of concrete. After fire exposure in the control mix, the residual compressive strength was 10 MPa. The waste aggregate concrete was found to be 26.9 MPa after 800 centigrade exposures, which was an excellent result. Waste materials decreased construction costs and led to a clean environment.

Restricted access

Abstract

Manufacturing ceramic green structures using starch consolidation casting is an established process that is simple, non-hazard, and low-cost. In this study, starch consolidation casting is used to prepare ceramics based on submicron monoclinic zirconia with additions of alumina and magnesia. Scanning electron microscopy results indicate that the size of pores decreased and the morphological irregularity increased when the tapioca starch content increased. The sample with 30 wt.% tapioca starch in a 55 wt.% slurry concentration had the highest estimated apparent porosity (around 56%), whereas the sample with 10 wt.% in a 68 wt.% suspension concentration had the lowest (about 35%).

Open access

Abstract

In the ever-changing realm of the contemporary workplace, adaptability and flexibility have emerged as crucial attributes for office buildings. The method of axes system design, in conjunction with modular structures, fosters a workspace that can seamlessly adapt to the evolving needs of offices. This system embodies a comprehensive approach to office design, emphasizing the integration of four important principles: modularity, adaptability, interconnectedness, and flexibility. The modular nature of the structural axes design allows for swift and cost-effective adjustments, facilitating customer needs. The dynamism of this system ensures that office spaces are in a perpetual state of evolution, reflecting the changing dynamics of the contemporary workplace as to be shown in this paper.

Open access

Abstract

Plastic pollution of oceans and seas is increasing every year and coastal countries need to pay particular attention to this problem. Four Asian countries – Japan, China, Singapore, South Korea – were analysed in terms of the amount of waste and plastic waste generated and their recycling rates. For each country, available data were collected and converted into a common unit of measurement – metric tonnes per 1,000 people. The countries' performance to date was analysed and used as a basis for projections for 2030. Based on the trends so far, Japan has seen an 11% reduction in plastics waste and a 6% reduction in waste over the period, while China has seen a 27% increase in waste and an 8% reduction in plastic waste. In South Korea, plastic waste increased by 49% and waste by 21%. In Singapore, waste decreased by 13% and plastic waste increased by 15%. On current trends, none of the countries are projected to reach their 2030 targets. However, by complying with current and newly introduced regulations, they have a chance to move closer to their targets.

Open access

Abstract

This study investigates sustainable methods for producing protein from soybean expeller via pH-shifting processes, aiming to reduce water usage in alkaline extraction by adjusting solid-to-liquid ratios per cycle and employing isoelectric precipitants like lactic acid and lactic acid bacteria (Lactiplantibacillus plantarum and Lactococcus Lactis) to enhance functional and antioxidant properties over a wide pH range. Results indicate that the most efficient approach involves three 1:10 (w/v) extraction cycles with lactic acid bacteria as precipitants, demonstrating high productivity and low specific water consumption. Protein content and recovery yield showed no significant differences compared to alternatives with higher water consumption or less eco-friendly precipitants. Despite lower solubility, protein products precipitated with lactic acid bacteria formed stable emulsions, exhibiting superior free radical scavenging activity.

Restricted access

Abstract

Microencapsulation of flaxseed oil (FO) has received lots of attention in the food and biopharmaceutical industries. To produce FO microcapsules, aqueous emulsions of FO with polymeric carbohydrates (maltodextrin (MD) with dextrose equivalent (DE) 19, gum Arabic (GA) and modified starch (MS)) were prepared by a rotor stator homogenization and subsequently, dehydration of emulsions were performed by spray drying (SD). The objective of this research was to study the effects of different combinations of polymeric carbohydrates with FO in emulsion to obtain maximum encapsulation efficiency (EE). A 3 factorials–3 levels Box–Behnken design was used for the optimization purpose. The maximum EE was achieved using 0.79 MD-GA ratio, 20.23% MS and 24.62% FO in emulsion. Microcapsules obtained by optimum condition had EE 77.68%, particle size (D 32) 120.0 ± 0.43 μm, moisture content1.6 ± 0.13%, wettability 192 ± 5.5 s, solubility 75.49 ± 1.3%, bulk density 0.31 ± 0.025 g mL−1, tapped density 0.36 ± 0.01 g mL−1, Carr's Index 13.88 ± 0.01% and Hausner Ratio 1.16 ± 0.01.

Open access