LANDSLIDE PROTECTION OF ROADWAY NETWORK DURING THE CONSTRUCTION AND RECONSTRUCTION

https://doi.org/10.52326/jes.utm.2022.29(1).10

UDC 625.7:551.435(478)

Vladimir Polcanov, Alina Polcanova, Alexandru Cîrlan

Abstract. The article discusses an example of construction and operation of a high embankment of the road, which was constructed in the central part of Moldova. A detailed historic reference about the behavior of the embankment over 40 years of its operation is given. The reasons for the repeated deformations of the embankment have been identified. The analysis of the effectiveness of the undertaken landslide prevention works has been performed. In order to increase the effectiveness of landslide protection, the authors propose a procedure for multifactorial analysis of the interaction of complex natural systems and various engineering structures, which will allow designers to reasonably predict and make accurate design decisions in diverse geological settings.

Keywords: effectiveness, embankment, highway, landslide deformations, landslide prevention works, rheology.

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REGARDING THE CHARACTERISTICS OF THE WIND IN NORTHERN REGION DISTRICTS OF THE REPUBLIC OF MOLDOVA

https://doi.org/10.52326/jes.utm.2022.29(1).11

UDC 551.55:504.3(478)

Octavian Mangos, Vasile Rachier, Ion Sobor, Vadim Cazac

Abstract. The study is focused on three districts in the northern region of the Republic of Moldova – Briceni, Edinet and Ocnita. The maps were calculated and presented in terms of average annual wind speed and wind power density at a height of 100 m above ground level, wind rose and Weibull wind speed distribution. In the calculations performed for the three analyzed districts it was found that the average annual wind speed is between 6.84 and 7.35 m / s, and the wind power density – between 450 and 593 W / m2. The highest annual average speed equal to 7.35 m / s was identified in Ocnita district. At the same time, having the maps of the wind speed and the power density, the convenient locations for the construction of the wind farms can be selected. For each district involved in the study, a location with a pronounced wind potential was identified, recommended for the location of any wind farms.

Keywords: wind speed; power density, wind atlas method, software package WAsP 9.1.

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BIOMASS PRETREATMENT AS A KEY PROCESS IN BIOETHANOL PRODUCTIONS: A REVIEW

https://doi.org/10.52326/jes.utm.2022.29(1).12

UDC 620.9:661.722

Toyese Oyegoke, Geoffrey T. Tongshuwar, John E. Oguche

Abstract. Solid wastes like lignocellulosic materials have proven to be of immense benefit to the production of bioethanol and have given a headway towards the deviation from the traditional use of fossil fuel which is has been a long-time primary source of fuel and energy globally. The transformation of lignocellulosic wastes into bioethanol is of importance to the environment. The recalcitrant nature of this substance, owing to the presence of lignin which serves as a deterrent, making it hard to access cellulose and hemicellulose, which are later converted to bioethanol, has raised much concern for researchers. Various strategies for feed preparation for overcoming this problem have been identified by researchers in the literature, including chemical, physical, and physiochemical approaches with enzymes. This review aims to bring together recent advances made by researchers in different pretreatment methods in optimizing the production of bioethanol. The advantages, disadvantages and the specific conditions for these pretreatment methods are also discussed in this review. Embedded in this review is also a report of the usage of some of these feed preparation strategies and the amount of bioethanol that was obtained by each process using different feedstock.

Keywords: Bio-alcohols, biofuels, biorefinery, environment, wastes, cellulose, pollution.

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COLOR STABILITY OF YOGURT WITH NATURAL YELLOW FOOD DYE FROM SAFFLOWER (CARTHAMUS TINCTORIUS L)

https://doi.org/10.52326/jes.utm.2022.29(1).13

UDC 637.146.34:667.275.5

Liliana Popescu, Aliona Ghendov-Moșanu, Alexei Baerle, Alexandra Savcenco, Pavel Tatarov

Abstract. The article elucidates the possibility of using the yellow dye, obtained from saffron petals (Carthamus Tinctorius L.) in the food industry. This powdered dye, added to yoghurt in concentrations of 0.3 – 0.4%, in addition to its yellow color, gives the yoghurt samples a light aroma of saffron flowers and demonstrates high stability during storage at 4° C. for 28 days. The values of the chromatic coordinates, L *, a *, b *, of the yogurt samples did not undergo considerable changes during the storage stage, the color difference ΔE being ≤ 0.79, which indicates a high stability of the dye in yogurt. samples. The chromatic analysis data correlate with the results obtained by the reverse phase HPLC method, which identified the presence of four intact yellow chalcones in the yoghurt. The results of this study will encourage the cultivation of saffron, the extraction of natural dyes and their use in the food industry.

Keywords: chromaticity coordinates, color analysis, food additive, natural food.

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POSSIBILITY AND NECESSITY OF TARTARIC ACID PRODUCTION IN THE REPUBLIC OF MOLDOVA

https://doi.org/10.52326/jes.utm.2022.29(1).14

UDC 661.746.3:663.26(478)

Vladislav Reşitca, Anatol Balanută, Iurie Scutaru, Ecaterina Covaci, Aliona Sclifos, Antoanela Patraș, Ana-Maria Borta

Abstract. The wine industry has been and remains a source of natural- tartaric acid. The tartaric acid can be obtained from such wastes as grape marcs, yeast, vinasse and wine stone. But the use of these wastes was limited in the Republic of Moldova by the production of tartaric acid lime (calcium tartrate) and wine stone, which were shipped to Ukraine and Armenia where the finished product is obtained. Currently, tartaric acid is used in considerable quantities in the winemaking and food industry, being a quite expensive imported product. The Department of Oenology and Chemistry has developed a complete technological scheme for the use of wine wastes to obtain the finished product – tartaric acid. The realization of the proposed tartaric acid production in the Republic of Moldova is important for the country’s economy and it does not require large investments. Wineries can also help to organize tartaric acid production by providing calcium tartrate, wine stone, pressed or dried yeast, and other ingredients.

Keywords: tartaric acid, calcium tartrate, winemaking, circular bioeconomy, vinasse, wine stone.

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ANTIMICROBIAL PROPERTIES OF SEA BUCKTHORN GROWNIN THE REPUBLIC OF MOLDOVA

https://doi.org/10.52326/jes.utm.2022.29(1).15

UDC 634.743(478)

Elisaveta Sandulachi, Artur Macari, Daniela Cojocari, Greta Balan, Sergiu Popa, Nadejda Turculet, Aliona Ghendov-Mosanu, Rodica Sturza

Abstract. This study deals with the antibacterial activity of Sea buckthorn (SB) (Hippophae rhamnoides L.) grown in the Republic of Moldova. Eight sea buckthorn species were investigated: R1, R2, R4, R5, C6, AGG, AGA, Pomona, 2020 harvest, from Dubasari district, Pohrebea village of the Republic of Moldova. The sea buckthorn fruit was harvested during the complete sweeping phase. The antibacterial efficacy of Sea buckthorn on different microbial cultures (Staphylococcus aureus, Bacillus subtilis, Salmonella Typhimurium, Escherichia coli, Candida albicans) causing infections/diseases was investigated by agar disc diffusion method. The inhibition zones ranged from 12 to 30 mm: Staphylococcus aureus ATCC 25923 (21-30 mm); Bacillus subtilis ATCC6633 (19-29 mm); Salmonella Typhimurium ATCC 14028 (13-18 mm); Escherichia coli ATCC 25922 (12-18 mm). In the case of Candida albicans ATCC 10231, this fungal pathogen was resistant to SB. It was found that antimicrobial efficacy of SB depends on the species, concentration, and form of use (fruit puree, extracts with different solvents and powder). Results suggested that SB might be a valuable ingredient for the development of safe products for consumption.

Keywords: Hippophae rhamnoides L., Gram-positive bacteria, gram-negative bacteria, inhibition zone, food safety.

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