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The aim of this study was to evaluate the influence of several extraction methods on the content of bioactive compounds of polyphenolic structure and antioxidant properties of petals from marigold flowers (Calendula officinalis). Ethanolic extracts prepared using maceration, turbo-extraction and bead-beating techniques were investigated for total phenolics, flavonoids and tannins, and antioxidant activities as measured by FRAP and DPPH assays, as well. The results showed that the highest phenolic content (1316.367...

Accurate estimation of greenhouse gases in national inventory reports, submitted by countries every year under the UNFCCC and the Paris Agreement is an important task. Fugitive greenhouse gas emissions from oil production, gathering and treatment is a key category in the Russian national inventory report. Total emissions from this category accounted to more than 30 million tons of CO2 equivalent in 2021. Since in Russian inventory the default IPCC emission factors from these operations are used, in the framework o...

Among the important parameters determining the likelihood of occurrence of significant damage to engineering structures during an earthquake are the dynamic and seismic characteristics of the structures such as natural frequency, damping coefficient, and vulnerability index of the structure. In this article, the Nakamura method is applied to investigate the seismic stability of an earth-filled dam wall and the surface layer using microtremors. Measurements were taken at seven points on the dam crest and three poin...

The analysis of the dynamic and fractal properties of the released seismic energy time series allows for the classification of the seismotectonic system that produces earthquakes as a deterministic-chaotic system. The dynamics of such systems suggests that relatively small changes can lead to significant (with one or more order large) jumps. At the same time, the size of these jumps and the intervals of time that separate them are irregular, and the possibilities for their prediction are limited or absent. In this...

An earthquake catalogue covering the seismicity on the territory of Bulgaria and adjacent lands for the period 2000-2020 is presented in the current study. In this catalogue are included events with magnitude equal to or larger than Mw ? 2.5. As a country, Bulgaria belongs to the Alpo-Hymalian seismic belt, it is also not absent of strong earthquakes. Bulgaria is an earthquake prone country taking in account that on its territory are recorded some of the strongest earthquakes from the beginning of the last century...

The COVID-19 coronavirus pandemic has negatively affected all sectors of the economy around the world. At the same time, tourism was one of the most affected business sectors. The history of tourism shows that the industry is exposed to crisis phenomena earlier than any other sphere of economic activity, but it adapts to new conditions much faster and more flexibly. The crisis of 2020-2021 is usually compared with other crises that the tourism industry experienced in the 2000s in Russia. In this paper the characte...

The purpose of this study is a spatial-dynamic and structural hygienic assessment of the impact of the activities of thermal power facilities on the quality of atmospheric air and the formation of potential risks of harm to the health of the population in a large industrial center with a population of more than 350 thousand people and a total area of more than 500 square kilometers. At present, heat and power facilities belong to the main industries and form significant potential risks of harm to public health in ...

The traditional ?linear? path of business doing must be changed according to the new principles of circularity, because the circular economy is considered to be a new economic system for society and economies at a macro level. At a micro level, the circular economy represents the ultimate business strategy. The circular economy eliminates the concept of waste, because waste is conceptualized as a resource. The mission of the circular economy as a new philosophy is to change the production of global economies, as w...

The ecological situation of the Arctic and sub-Arctic areas has been given special attention due to their extremely vulnerable environment. In comparison with other areas, the Arctic remains a clean environment, but heavy metals occupy a special place among priority pollutants. There are a lot of studies of heavy metals in the soil, but not enough information on the joint content and physicochemical factors that affect the metals accumulation in the Arctic soils. Therefore, this paper presents identification of co...

This work presents an overview of the basic image processing techniques and some of their applications to important tasks in geosciences including, segmentation of satellite and airborne images and environmental modelling. Methods based on linear and nonlinear filters are discussed, as well standards for storage of image containing information.

It is presented in the paper two approaches for geographic data storage and maintenance in Relation data base management system (RDBMS). The methods for data indexing and organization of data storage in DB are discussed as follows: Creating of spatial index on the basis of Quad-tree, applied in the ORACLE 8i module - ORACLE Spatial; Creating of spatial index on the basis of R-tree or rectangle grid coverage over the map with spatial data applied in ORACLE Spatial and ESRI SDE (Spatial Database Engine). The discuss...

This work shows presents an overview of the basic morphological techniques and some of their applications to important tasks in geosciences including radar image segmentation and despeckling, object detection on aerial photographs, analysis of images of bore holes etc.