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Three photovoltaic (PV) systems with the identical solar panels, the same charge controllers, and similar loads, but with different used battery types: AGM deep-cycle, LiFePO4 and lead-carbon were installed in Riga, Latvia for a long-term monitoring and analysis of the operation efficiency and potential energy losses in batteries under real operation conditions. Results of one full year of monitoring are analysed in this paper resulting quantitative indicators during different seasons. During the wintertime with l...

The global development of society requires constant updating of the objectives that education pursues and how they are achieved. Science education is an area undergoing advanced transformation, both at the level of objectives and methodologies, with a strong social, economic, and knowledge impact. Research-based education is a well-established term, especially in the higher education system. More studies and key policy documents argue that education must be based on cutting-edge research. Essential in this equatio...

The Eastern pasqueflower (Pulsatilla patens (L.) Mill.) is considered as an endangered species in all European countries where it is found, including Latvia. An important factor for the survival of P. patens - a species with low competitiveness is not only the conditions suitable for germination and further growth, but also the indicators of seed viability. This is particularly important as there is no persistent soil seed bank for this species. Only limited data is available on the factors affecting seed viabilit...

Contemporary urban meadows as an alternative to amenity mown grass in public green spaces are the solution for biodiversity growth and human wellbeing. In the publication, we present the results of research monitoring the development of flower meadow growth in the urban environment. We focus on the analysis of visual and other properties of herbs, on the basis of which we evaluate the visual and other properties of the flower meadow stand. The result is an evaluation of the suitability of flower meadows in terms o...

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...

The food spectrum of three fish species from the Mugilidae family in different age groups was studied. The samples were collected in 2019 - 2021 from the river estuaries and the coastal brackish lakes at the Bulgarian Black Sea coast. The research aims to establish the food spectrum of mullets and thus make a connection between food components. The results show that the predominant groups in the stomachs of the three mullet species are detritus, zoobenthos (Rissoa sp. And Trochammina inflate - 64.28%) and macrophy...

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...

Awareness of the importance of sustainable agriculture has increased in recent decades. One of the reasons for this is the widespread use of synthetic pesticides and their possible secondary negative effects on valuable carnivores and biodiversity. Therefore, the need for biological and environmentally friendly alternatives to pest control has become relevant. This relevance is also reinforced by the European Union's Green Deal agenda and its underlying strategy - Farm to Fork, which aim to mitigate climate change...

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...

The growing number of wind farms is creating an increased demand for their trouble-free operation. Damage to their components can be catastrophic. A particular component that can be subject to damage during long-term operation and is difficult to diagnose is the mechanical gearbox located in the turbine. Traditional approaches to the subject of damage detection require, in the final stage, the involvement of an expert. Therefore, the article proposes a method based on the Deep Learning solution. A transfer learnin...

The process of anaerobic fermentation of organic waste makes it possible to produce not only methane, but also hydrogen, which, when mixed, form a high-energy mixture - biohythane. The efficiency of biohythane production in a two-stage anaerobic fermentation process depends on many factors, including organic loading rate (OLR) and hydraulic retention time (HRT). It is known that the addition of an immobilizing support materials to anaerobic bioreactors improves the stability of their operation and increases the bi...

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...

The concept of Best Available Techniques (BAT) is the basis for granting Integrated Environmental Permits (IEP) to industrial installations. In Russia, BAT is used along with Best Environmental Practices (BEP) concept to promote resource efficiency solutions and to motivate managers to collaborate with local stakeholders in the field of environmentally sound activities. One of the sectors modernised in accordance with the principles of BAT is municipal wastewater treatment (MWWT). In 2020, the Russian Reference Do...

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...

Modern way of life using means of producing energy through renewables and forming a part of energy communities and citizen energy communities represent innovative resources. National Recovery and Resilience Plan (NRRP), redefines an update of the objectives of both the Integrated National Energy and Climate Plane (INECP) and the long-term strategy for the reduction of greenhouse gas emissions, to reflect the changes that have occurred in the meantime in Europe. In detail, this article aims to ponder on the path ta...

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...

The impact of anthropogenic greenhouse gas emissions on the increase in the average temperature on the planet and the risk of initiating irreversible processes are recognized by most of the scientific community as real threats to humanity. Many countries have a legal and institutional framework for a consistent industrial policy taking into account the climate and environmental components, including carbon accounting. Russia is a country with high intensity of production-based CO2 emissions. In is well-known that ...

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 study presents a detailed analyse of the morpho-dynamic processes of the main two bifurcations of the Danube River within its delta, at Ceatal Izmail and Ceatal St. George. The first bifurcation of the Danube, called Ceatal Izmail; here the river divides into two distributaries: a northern one, the Chilia (Kilia), and a southern one, the Tulcea. Forking to the right at Ceatal Izmail (Mile 43), the Tulcea distributary stretches further to 17 km to the second main hydrographic knot Ceatal Sfantu Gheorghe (St. Ge...

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 studies presented in this paper, were aimed at testing, in order to extend the applicability of the methodology for approaching biomonitoring methods to new domains of activity by using bioindicators. The proposed and applied methodology aimed to add new complex studies, some of that not previously used, combining macroscopic, microscopic and biochemical analyses of selected and exposed bioindicators compared to control bioindicators maintained under standardized conditions in the climate chamber. The change o...

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...

The present work is an attempt to create a biosurfactant producing consortia on the bases of initial rhizospheric community of lettuce plant (Lactuca sativa). To obtain consortia, 47 strains from the rhizosphere were isolated and checked upon their ability to produce biosurfactants. The ability of the isolates to produce biosurfactants was analyzed on the basis of their ability to emulsify crude oil (E24 index). The isolates with the highest E24 were Bacillus. oryzaecorticis (80%), B. simplex (65%), Paenibacillus ...

The most significant challenges of organic farming are the fragmentation of the sector, unstable product supply and sales opportunities, as well as the lack of knowledge of how to manage agricultural production agronomically and economically effective. The predominant form of agricultural enterprises in Latvia is small and medium-sized farms. Thus, cooperation is an effective solution so that farmers can maintain the form of a family business and achieve an appropriate economic market, which would contribute to th...

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...