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According to ANSYS - developer of the Multiphysics platform for computer simulations - the FSI (Fluid-Structure Interaction) model can be used in all cases where a fluid encounters a solid structure, for example, wind gusts rotating a turbine, air washing the surface of a moving car etc. This method finds applications especially in the aeronautical and automotive industries, but also in medical research, such computer simulations track the influences of blood pressure and blood flow velocity in the veins. This pap...

Geopark is a region that has a complex special protected status, on the territory of which the geological history of the Earth, the formation of local landscapes, expressive geological formations, and layers of fossil fauna are clearly revealed. A geopark is not only a geological heritage, but also habitats for biological species, interconnected ecosystems, it is a cultural and historical heritage. Geopark is a favorable environment for the development of ecotourism and related business. UNESCO Global Geoparks are...

Romula, the most important urban settlement of Dacia Inferior (Dacia Malvensis) province of the Roman empire during the 2nd and 3rd centuries A.D., was located in the present-day Resca village-Dobrosloveni commune, Olt County, Romania. Most of the Roman town remains are underneath Resca village premises, the areas suitable for archaeological or geophysical research being limited. This paper presents an integrated geophysical study carried out in the Central Fort zone of the archaeological site in September 2020, w...

Climate change and environmental degradation pose an existential threat to the EU and the world. The aim of the Green Agreement for Europe is to make Europe climate neutral by 2050, to support the economy through green technologies, to create a sustainable industry and transport and to reduce pollution. Turning climate and environmental challenges into opportunities will make the transformation fair and inclusive. The European Commission is helping EU Member States to design and implement reforms that support ecol...

Waste management is a public service, the provision of which is the responsibility of local authorities. The area of waste management is currently very strongly regulated in the national and European and at the same time monitored by the civil public with a strong context in public election processes. Expenditures on waste management make up a relatively substantial part of municipal expenditures not only in the Czech Republic but also in developed countries, which is why a number of economists are paying attentio...

Higher education institutions play a central role in shaping labor skills and green culture essential in the future low-carbon economy. This paper examines the impact of green education policies in the higher education sector on the business cycle and compares them to standard incentives to encourage green production at the firm level. For our purpose, we set up a Dynamic Stochastic General Equilibrium model extended to account for the endogenous selection of green and traditional human capital and heterogeneous h...

The study presents a developed instrumental and methodological complex designed to monitor changes in the state and development of dangerous processes in a natural and technogenic system, including the structural integrity of building structures and geodynamic processes in the soil rocks of their placement sites, including the activation of previously passive faults. The complex includes three orthogonal molecular-electronic linear displacement sensors and three orthogonal torsional vibration sensors which can sel...

The electrification process of the materials and technical equipment-s, especially the external parts of them, frequently occur during their use, being sometimes an intrinsic process, such as for example flowing of a flammable liquid through a pipe. The electrification process of materials and technical equipment-s is responsible for generating, through specific mechanisms, significant quantities of electrostatic charges. The presence of electrostatic charges on materials and technical equipment-s, used in areas w...

The Research Institute for Brown Coal j. s. c. (VUHU) has been involved in the research project of the EU Research Fund of Coal and Steel - The impact of extreme weather events on mining operations for four years. The project is focused on assessing the impact of climate change on mining activities in major European coal basins. Other participants are scientific teams from Poland, Great Britain, Spain, Germany and Greece. This is the last year of the project solving, so this paper summarizes the results of the sol...

The first oil discovery from Romanian Black Sea area was in 1987, relatively late compared with the first successful Romanian onshore well, more than 100 years earlier. Starting from that moment and continuing till recent years, several discoveries were done; some are already put into production and some others are still in the exploration phase. In order to extract as much oil as possible and also to define new hydrocarbon reservoirs, it is mandatory to have a proper understanding of the petroleum systems from th...

As the world adopts the technological era, the adverse effects of climate change have been experienced by the increasing population, which has led to a rise in energy demand. Heavy industries depend on dirty fossil fuels that release GHG emissions into the atmosphere. This paper aims to review the integration of a nuclear-renewable hybrid energy system (NRHES) to produce green hydrogen in decarbonizing hard-to-abate industries in the ASEAN region. In this study, the two main hydrogen production methods were identi...

The use of natural gas as a home heating source has, unfortunately, generated a number of gas explosion events, most of which have as their main cause the accidental leakage of combustible gas. The dynamic effects generated by the explosion pressures differ from case to case, depending on the concentrations of combustible gas accumulated in the chambers from the time of the occurrence of the gas leak to the occurrence of the source of initiation. Often, these dynamic effects involve concentrations close to the sto...

Ductile iron is currently one of the most popular construction materials. Its mechanical properties are close to those of steel. The basic material in the production of ductile iron is gray iron, which can be produced in a cupola or in an electric induction or electric arc furnace. After tapping the gray cast iron from the furnace, the gray cast iron is processing into ductile iron. This process is called modification. Magnesium and its alloys and cerium are most often used as modifiers. In addition to the modific...

Food waste is a growing global concern, with the attention of major global organizations focusing on monitoring and finding solutions to optimize it. According to the latest data published by the National Institute of Public Health on this topic (2019), in Romania, food waste is estimated at 6,000 tons per day 49% from households, 37% from the food industry, 7% from retail, 5 % of public catering and 2% of the agricultural sector. In this context, it was proposed to implement a system based on reducing waste and w...

Using remote sensing functional aspects of the landscape such as energy exchange between vegetation and the atmosphere, surface reflectance or vegetation heat flux can be monitored and evaluated in detail. Multispectral imagery is used to obtain information on the condition of the vegetation and plant growth, as it allows us to obtain information on possible nutrient deficiencies, pest damage or other manifestations of abiotic stress on the plants. Each surface reflects and emits radiation at different wavelengths...

The Varna and Beloslav lakes are the most strongly anthropogenized water bodies along the Bulgarian coast. At present, the lakes are again subject to deepening of the navigable channel, which significantly changes the quality of the habitats. An ecosystem approach was used to assess the status of the populations of fish species from the Varna-Beloslav Lake Complex. The paper's main purpose is to provide up-to-date information on the ichthyofauna of the largest northern Bulgarian Black sea brackish water bodies - V...

A study was made of the influence of ZSM-5 zeolite on the composition and properties of the products of fast pyrolysis of flax shives in the temperature range of 350-750 -C. Zeolite ZSM-5 increased the heat of combustion of gaseous products, as well as the content of methane, ethylene, hydrogen, and carbon dioxide, which is probably associated with the processes of cracking of volatile products passing through a layer of a catalyst heated to high temperatures. The synthesis and study of zeolite catalysts ZSM-5 con...

The main idea of the article is to assess the landscape potential for the use of renewable energy systems based on systematic and landscape-ecological approaches. In general, these approaches consist of the analysis of the features of landscape components and their impact on the redistribution of energy flows in the landscape, which in turn form the potential of renewable energy resources of each specific landscape contour. A systematic approach is to consider the holistic properties of a particular landscape in t...

Recently, the study of new methods of extraction from vegetable raw materials, such as ultrasonic extraction, microwave extraction and extracritical fluid extraction, has become widespread. The results of the study of ultrasonic extraction in the literature showed that this process provides higher selectivity, has a shorter duration, reduces energy consumption and harmful emissions into the environment. And it is also made in the equipment which design is much simpler than the equipment for pressing. In addition, ...

The waste management sector as one of the most significant economic sectors requires effective management not only in Latvia but in the European Union as whole. According to the recent (2020) available Eurostat data, 505 kg of municipal waste per capita were generated in the EU of which 48% were recycled and 22% were landfilled. Latvia ranges in the 11th position among the EU Member States with 478 kg of generated waste per capita. Romania (287 kg), Poland (346 kg) and Hungary (364 kg) are countries having generat...

A small quantity of flammable gas mixed with dust can cause a large explosion with severe consequences. In this study, hybrid mixtures explosion tests were performed in a constant volume 0.02 m3 spherical vessel. Five pressure-time curves were recorded. The effects of initial temperature on burning velocity were investigated for Lycopodium Clavatum-methane-air hybrid mixtures. The most important results from evaluated experiments are the values of burning rates to understand better the fundamental flame methane-ai...

When considering environmental priorities in the Moscow region, it was pointed out that not only human economic activity damages the environment, but also resources a significant part is destroyed by fires and other emergencies, which number has been increasing in recent years. Land resources are among the main exhaustible resources without which human existence is impossible. State activity, first and foremost, must be aimed at the land resources effective management and protection against the human economic acti...

The aim of the article was to assess the importance of Natura 2000 sites in halting land take, given that the European Commission has set itself the target of reducing land take in the EU to zero by 2050. In the surveyed area, land take is primarily a consequence of the economic activities carried out and of their pace and intensity; the density of housing also puts pressure on the phenomenon through the permanent expansion of the built-up area of the settlements (the brown belt), especially in the economically ef...

Species of macrofungi were collected from extremely polluted sampling spots in the vicinity of abandoned antimony mines in Slovakia. Concentrations of potentially toxic elements in plants and fungi were determined by ICP-MS and in soils and sediments by both ICP-MS and ICP-ES. Of the edible species the highest values of arsenic and cadmium were recorded in Agaricus arvensis, lead in Imleria badia and representatives of the genera Boletus, Leccinum and Suillus accumulated high levels of mercury. Suillus species als...

The presented paper represents a comprehensive analysis of hydrous ferric oxides (HFOs) precipitated from Fe rich drainage waters contaminated by arsenic and antimony. Ochre samples from three abandoned Sb deposits were collected in three different seasons and were characterized from the mineralogical, geochemical, and microbiological point of view. They were formed mainly by poorly crystallized 2-line ferrihydrite, with the content of arsenic in samples ranging from 0.7 wt.% to 13 wt.% and content of antimony ran...

The production of oil and gas includes drilling a number of wells for exploration or production activities. During drilling operations, large volumes of drilling fluids are used to facilitate the process. In Libya, after completion of drilling operations drill cuttings and waste drilling fluids are typically discharged close to the oil fields without treatment. This can result in negative ecological impacts on the surrounding environment e.g. through infiltration of toxic constituents into soils and underground wa...

The aim of this study is to determine the prospects of the region for the identification of new objects. For this purpose, it was necessary to solve the tasks of analyzing and summarizing all available geological data on the Torgai trough and based on this, to make forecast maps and determine the prospects for identifying deposits. Analysis of extensive factual data and outcomes of the sedimentary cover minerals was followed by interpretation of sections at the basic outcrops and wells. All this work resulted in c...

For many years, oil derivatives, natural coal, and natural gas were used and still are, as primary energy supply due to their calorific potential, and their great availability on the planet. However, the utilization of these feedstocks causes greenhouse effects and helped in global warming, creating a general concern about this issue, and leading to the creation of urgent measures to overcome these problems. Hence, guidelines and public policies were granted to guarantee the reduction of emissions and increase the...

The high performance characteristics of Peltier thermoelectric modules (TEM) in comparison with compressor cooling systems are determined by the convenience of their use for both cooling and heating, technological advantages due to the absence of moving parts, etc. To effectively regulate the temperature conditions of TEM, it is necessary to develop automatic control systems with specified characteristics. Modeling and design of such systems is complicated by the essentially nonlinear properties of the constituent...

The Durankulak Lake is the northernmost Bulgarian Black Sea lagoon. The hydrological regime of the lake is, for the most part, the inflow of water in karst underground cracks. Over the years, the rare cases of digging a sea-lake canal have been a significant cause of the oligohaline estuarine wetlands nature of the water body. The publication aims to present current research on the structure of the lake bottom, the heart of the substrate and changes over the years, using data from a multi-beam echo sounder and sid...

The increase in human population brings an increase in consumption, higher pressure in often limited space and growth of waste, particularly in communal environments. Out of the huge volume of communal waste, a portion is composed of biologically degradable and other waste, that could be recycled utilizing eco-friendly means - e.g. fungal activity. This includes plant waste from gardens, yards, parks, orchards and forests, or plant debris not utilized by other ecologically and economically useful means. In this co...

Growing greenhouse gas emissions are a primary cause of global warming and climate change, with transportation accounting for the largest proportion. Many countries have started to develop strategies to promote the development of sustainable transport technologies. In terms of fossil fuel independence and reducing carbon emissions, electric vehicles (EVs) are a highly developed and efficient solution with growing popularity. This study looks at the major socio-economic and perception-related obstacles to the much ...

The study of ultra-low frequency (ULF) waves and geomagnetic pulsations plays an important role in better understanding the mechanisms of their generation and spread in the magnetosphere and on the ground. The magnetospheric ULF waves, which provide useful information about the conditions in the solar wind and in the magnetosphere, can be detected on the ground by different types of magnetometers and recorded as geomagnetic pulsations - continuous and irregular. This paper aims to study the characteristics of Pc5 ...

The quality and quantity of delta lakes- sediment depend on fluvial input and in-situ bio-geo-chemical processes. The present study investigates the quality of lacustrine sediments collected from two lakes - Tataru and Merhei, situated in different hydrodynamic environments within the Danube Delta, Romania, but both connected to fluvial input of water and sediment of the Danube. The following physical and chemical analyses have been carried out on several lake-bottom sediment samples: the main lithological compone...

Recently, hydrogen is often considered as one of the prospective clean energy carriers. However, the traditional hydrogen production methods also produce significant amounts of greenhouse gases or too expensive to be industrial scaled. In situ hydrogen generation in hydrocarbon-containing reservoirs can be one of the promising ways for low-carbon hydrogen production. However, the conversion of hydrocarbons into hydrogen under the hydrocarbon reservoirs conditions has practically not been studied. This work reports...

In recent years, with the rise of a growing economic and technological interest in lithium mineral resources, there has been a parallel concern, on the part of some local populations and even national environmental groups, for a hypothetical contamination problem that this type of exploitations may cause on the quality of groundwater. Thus, the present study was based on an evaluation of an open-pit quarry, in the socalled Alijo quarry, located in the North of Portugal, in the parish of Canedo, Ribeira de Pena mun...

The evaluation of radioactivity levels was performed on milk samples collected biannually for a period of 10 years (2012-2021) from two Central Romanian counties, Sibiu and Alba. The radioactivity concentrations in milk samples originated from Sibiu varied from 0.028-0.001 Bq/L to 0.347-0.017 Bq/L, from 24.017-0.977 Bq/L to 65.403-6.281 Bq/L, from 0.090-0.010 Bq/L to 0.110-0.010 Bq/L, from 0.085 to 0.110 Bq/L, for gross alpha, gross beta, 137Cs and 90Sr, respectively. The radioactivity concentrations in milk sampl...

The purpose of this article is to assess the quality of soil and water environmental factors in some protected areas in Romania both to establish geochemical threshold values and to highlight anthropogenic pressures where they have been identified. The activities carried out are defined spatially and temporally so that the results obtained include seasonal variations and other influencing factors that have a variability on a temporal and spatial scale. Each protected area introduced in the study was well documente...

For the period 2011-2021, 231 fish species from 18 families were established in protected area BG0000271 -Mandra-Poda-, 345 fish species from 7 families in protected area BG0001502 -Otmanli- and 169 species from 11 families in a protected area BG0000242 -Chengene skele Bay-. One hundred eighty-seven of the species were freshwater, 256 were typical marine fish species, and the other one hundred and fifteen were anadromous and brackish species. Protected species are Rhodeus amarus, Cobitis taenia, Chalcalburnus chal...

Both domestic and wild rabbits are susceptible to an increased number of parasites, however, only few are of economic importance. The aim of this study was to identify the endoparasite species present in domestic and wild leporidae from Caras-Severin county, between April 2021 and March 2022. A total of 157 leporids, 111 domestic rabbits (Oryctolagus cuniculus) and 46 wild rabbits (Lepus europaeus) were included in the study. The rabbits were grouped into three age categories: 4 months, 4 months - 1.6 years, 1.6 y...

In recent years, the development of resistance to various antibiotics frequently used in veterinary practice has been observed. The cause seems to be the excessive use of antibiotics without doing an antibiogram. The aim of this study was to investigate the antimicrobial effect of different garlic extracts on Salmonella strains isolated from dogs. The research was carried out on a number of 19 strains of Salmonella spp. isolated from fecal samples from dogs. Salmonella spp is a bacterium with zoonotic risk. Differ...

Ammonium nitrate used as fertilizer is classified, according to Orangebook, as a hazardous substance in Class 5 Division 1 (5.1), oxidizing substances. Although, under fire conditions, ammonium nitrate burns in certain situations, the transition from combustion to detonation can occur. Such accidents have occurred in several countries, with significant quantities, including in Romania. Such catastrophic scenarios can occur in the case of nitrogen-based chemical fertilizers, in which case the manufacturing recipe (...

The significance of organic plant growth stimulants, in the development of sustainable agriculture and increasing the fertility of degraded soils has sparked the interest of scientists and practitioners working in the field of agriculture in recent decades. On the world market, there are numerous plant growth biostimulants of various origins and compositions, as well as numerous research analyzing their impacts and roles. The study aimed to determine the novel biological activity of the new Georgian biostimulants ...

The installation and maintenance of equipment intended for use in potentially explosive environments requires specific knowledge and qualifications for the personnel who commissions and subsequently maintain such equipment. When installing and maintaining electrical equipment, situations may arise which may in turn lead to an unacceptable level of risk with regarding to the activation of ignition sources of potentially explosive atmospheres in their immediate vicinity, due to the failure to comply the principles o...

By product is broadly understood as a product obtained in a usually industrial or biological process in addition to the main product for which the process is carried out. The main challenge addressed to humanity as well as productive ecosystems, regardless of the form of terrestrial or aquatic substrate, is to cope with the rapid rate of growth of the planet's population. The demographic growth of the planet must be in balance with the maintenance of the environment and also with climatic shifts. By-products are o...

Renewable energy plays a fundamental role for the Green Deal and for achieving carbon neutrality by 2050. EU Directive on renewable energy revised confirms the community block objective of obtaining 38-40% of energy from renewable sources by 2030, doubling the share of solar, wind and other renewables in Europe's energy mix by the end of the decade. The European Commission recommended that Romania increase the share of energy from renewable sources used for the year 2030 to at least 34% in a future analysis. Roman...

People hear about disasters that affect the whole world daily from various media sources. These disasters include natural disasters, disasters caused by mankind or a combination of the two. This includes the war that is happening in Ukraine. Many disasters can cause a fire to occur in buildings. With any fire in a building, a safe evacuation of people must be ensured. Thus, it is important to design buildings so that when people are evacuating, they are safe. Escape routes must ensure that all people can get to a ...

Surfactants produced by microorganisms, known as biosurfactants, have recently found wide application in the industry, from cosmetology to oil processing. Biosurfactants are more tolerant to extreme environmental conditions and less hazardous for the environment as compared with their chemical analogues. Despite on the fact that many biosurfactant producers have been recently isolated and described, the challenge to explore new producers still remains very urgent. In the present study, the isolates obtained from r...

The grass of the grasslands is the most accessible source of food for herbivores during a significant period of a year. The knowledge of the floristic composition of grasslands reflects the current state and is an essential element in determining the load of animals. This paper is a case study and aims to inventory the species participating in the grass cover near some localities in Western Romania. Vegetation surveys were made in March, June and the first quarter of October. The study method by which the vegetati...

The intensive development of remote sensing in the marine environment provides excellent bathymetric and substrate mapping opportunities on the southern Bulgarian Black Sea coast. The Bay of Chernomorets is a perfect opportunity to combine data from single-beam sonar, multi-beam sounding and drone imaging for the purpose of seabedforms and substrate mapping. This paper presents the second stages activity of the Project -Multidisciplinary study of Burgas Bay - MidBay. (Composition of a detailed digital model of the...