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Orphaned or abandoned sulphide tailing disposal sites pose significant environmental hazards, including eolian dispersion, water erosion, acid mine drainage, and heavy metal mobility. Phytostabilization, an eco-friendly strategy, entails the use of alkaline amendments alongside non-native plant species capable of thriving in environments with high concentrations of heavy metals. A greenhouse experiment was conducted to assess the effect of a commercial cement which contained 46.3% sand, applied alone or combined w...

This research compares the water quality in four river bodies passing through different cities in Bulgaria. An eco-chemical approach was applied including physicochemical and analytical measurements, as well as calculation of different pollution indices and the distribution of the element species as an indicator of their bioavailability. The results from analytical measurements and calculated pollution indices show that all the studied water bodies were polluted regarding P-PO43?, N-NH4+, Mn, and Pb. The highest v...

Ticks (Ixodidae and Argasidae) pose significant health risks as vectors for infectious diseases, with their prevalence expanding across Europe and North America. Ticks employ sophisticated sensory mechanisms, notably utilizing Haller's organs, to locate and sense their hosts. These sensory structures detect various cues, including chemosensation, changes in atmospheric CO2 concentration, and radiant heat emitted by potential hosts. Once a host is detected, landing is facilitated by electrostatic attraction, accele...

In this paper, there are presented the characteristics of reinforced concrete structures that are subjected to a corrosive environment. These structures allow for the appearance and opening of short-term and long-term cracks within certain limits during operation, as well as the variation in the moisture of the concrete depending on the ambient humidity. The basic nature of the concrete allows it to react with acids, while its increased porosity enables the absorption of liquids and gases, including aggressive one...

Biomass is the first form of energy used by man at the same time with the discovery of fire, means all the products of animal and vegetable origin used in present in the production of energy. Actually, the biomass approximately half (44-65 %) of the total renewable energy sources used in the EU, and occupies a third place as a primary energy source in the world, after coal and oil. At the same time represents a sustainable alternative to reduce carbon emissions. The experimental territory is located in the middle ...

Today, it is possible to work with a wide range of freely available data, often on a daily basis. These data can be used to create an early warning system for estimating the approximate hazard. It can also be used to develop models of long-term catchment behaviour. Most applications are generally carried out on catchments larger than 200 km2. For this reason, areas between 20 and 350 km2 were selected to test the hypothesis using models based on machine learning methods. How good results can be achieved when using...

The paper aims to identify the availability of water sources for water supply of local irrigation systems. Where the location of the land involved in the works is located at a large distance from the surface water sources, the only viable option is the use of water from the shallow water table. The identification, delimitation and characterization of underground water bodies is done in accordance with the specific methodology developed within the National Institute of Hydrology And Water Management, based on hydro...

In the evaluation activity of technical equipment intended to be used in potentially explosive atmospheres, by national and international legislation, non-compliant aspects were often reported regarding the choice, installation and maintenance of this explosion-proof equipment. The following main aspects were pointed out: the equipment that was initially chosen and installed appropriately for the specific application but later, over time, improperly maintained; respectively, the situation in which they were inappr...

Geophysical studies on the lunar surface have, in the past, used various methods that contribute not only towards the knowledge of the lunar subsurface but also contribute towards the design of future lunar missions, namely those that will, in the near future, take humans to the Moon-s surface. This work analyzes a specific set of ground penetrating radar (GPR) data, collected during the Chang-E-4 mission of the Chinese Space Agency, using theYutu-2 rover within the von Karman crater, on the far-side of the Moon. ...

The research objective was to develop a methodology for determining the total suspended solids concentration in wastewater based on the color indexes analysis. Determining the structure and properties of natural objects by processing its digital images has become widespread in soil science, since the soil colour is determined by its chemical and mineralogical composition. The material presented in the research can be considered as the initial steps in the development of soil science methods as applied to research ...

Effectively preventing pipe sticking in oil and gas wells is a key aspect of safety and productivity in the oil and gas industry. This paper presents a new torque and drag model developed using machine learning techniques to improve accuracy and predictive capabilities. The model is based on a comprehensive analysis of many factors, including geological characteristics of the well, drilling parameters, fluid parameters, hydraulic conditions, and production equipment parameters. This research explores the applicati...

The groundwaters draining in the continental shelf area can be an unconventional resource of fresh water for drinking, irrigation, and industrial purposes in water-scarce coastal areas. Recently, possible offshore sources of such groundwater in the coastal zone have been subject of increased investigation and description. The aim of the present research is to identify similar, available for use, potential sources of Offshore Frehsened Groundwater (OFG) in the area of the shelf of the Northern part of the Bulgarian...

The results of our study revealed regional peculiarities, which showed an excess of the share of PM10 compared to PM2.5 in the rank distribution and high concentration of soot in the level of impact on public health. It was found that the distribution in terms of contribution to the total risk value (HQ) of the main pollutants is highest in all three zones: carbon (soot), nitrogen dioxide (NO2), suspended solids (PM), where the main share is suspended particles up to 10 microns (PM10). Among the studied zones, zon...

In the present study probabilistic earthquake, scenarios for the city of Varna the third-largest earthquake-prone city in Bulgaria are presented. The probabilistic hazard for a city is obtained by integrating the effects of ground motion from earthquakes of different size occurring at different locations within different seismic source regions and with different frequencies of occurrence. The ground motion maps for the city of Varna are generated combining via GIS, source geometry, earthquake occurrence model, max...

The most attractive option to recover methane trapped within natural gas hydrate reservoirs, consists of the so-called -replacement process-, mainly based on the contemporary injection of carbon dioxide during the mining process. If appropriately carried out, this process allows to improve the amount of methane recovered, preserve the crystalline hydrate cages and permanently store enough carbon dioxide to make this source definitively carbon neutral. For that reason, this process is widely studied worldwide. Howe...

Bioeconomy industries play an important role in contributing to national economies and a transition to climate-friendly farming practices. This is evidenced by various policies implemented, including the United Nations Sustainable Development Goals, the European Union (EU) Bioeconomy Strategy and the European Green Deal. The increasing productivity and new technologies can have negative environmental impacts, affecting the economic framework associated with ecosystem services. To address these challenges, coordina...

Technological advance has assured humanity-s desire to increase its quality of life, anyway humanity is currently confronted with several global challenges, their complexity bases on their interconnectedness, and on fast changes in technological field. Present space activities are directed to explore the potential of diverse celestial bodies to have hosted life. In this context the Moon Village Association, MVA has as its main objective creating a global informal forum for governments, industry, academia for debat...

Geographic information systems (GIS) are based on the approach of displaying data from individual layers, where a manageable number of geospatial objects are displayed within a single layer. The entire content of a hydrogeological model (HM) can only be partially included within this framework. HM input data and modeling results as layer surface maps are a way to easily, clearly, and simply publish the model content and simulation experiment results. However, this approach is not sufficient for regional HMs. Regio...

Potential environmental impacts of growing maize as monoculture lead to efforts focused on finding other potentially suitable crops or their combinations that could replace the pure maize cultures. The most frequent and most effective combination is a mixed crop of maize and legumes. The presented paper deals with the issue of the quality of post-harvest residues when growing maize in the system of mixed cropping. In the field experiment, yield and quality of post-harvest residues were studied during the growing s...

Receiver function analysis is a critical tool in seismology, used to study the deep structure of the crust and upper mantle. Information about the deep structure of the crust and seismicity is important initial data for developing a source model and seismic hazard assessment. The presence of sharp discontinuities beneath the monitoring station induces the generation of converted body waves, which propagate at slower velocities than those of the primary P-wave. Receiver function analysis utilizes the lag between th...

Snow cover is an indicator of the fluctuating climate, resulting from the change in the regime of winter precipitations and air temperatures. Our previous studies have revealed significant decreasing of the seasonal snow cover maxima and the precipitation amounts in the highest mountainous regions of Bulgaria, which is however not so strong at lower altitudes. Current research summarizes our last findings about one other characteristic of the snow cover - its duration. This is presented as annual number of days wi...

The depletion of primary raw materials and the demand in High Tech has played a big role in finding new ways of getting raw materials including recycling. Germanium being a semi-conductor currently in high demand is being sourced from secondary materials. The purpose of this project was to recover Germanium from copper slag in the presence of pure silicon using the carbothermic reduction process. The experiment was designed using Minitab software with Taguchi as the tool for statistical analysis and to design the ...

Oilfield brine extracted with hydrocarbons is often considered as a problematic waste. The typical management option for this produced water is reinjection into the formation to maintain the reservoir pressure (or just for disposal). High salinity of produced water is on the one hand a drawback, but on the other hand an advantage because it can be used as a raw material for the production of valuable chemicals. In this paper a freezing-thawing desalination method was tested to obtain partially desalted water and c...

Drawing on case studies from 18 countries, the paper explores how project management methodologies are applied in European whisky industry to implement and optimize recycling initiatives, focusing on key processes such as glass bottle return schemes, advanced waste sorting technologies, and material reuse strategies. Critical project management insights include the importance of stakeholder engagement across production, sustainability, and regulatory teams, and continuous application of lean management principles ...

The lignocellulosic biomass is produced worldwide in large quantities, which may contribute to environmental changes, global warming, wildfires, ocean and sea level rise. Recent research demonstrated efficacy of the thermal reconversion of black liquor, which represents a waste resulted from wood Kraft pulping, into gaseous (syngas), liquid (bio-oil) and solid (bio-char) final products through the pyrolysis process. This review describes the physical chemical and energy features of black liquor required for its va...

The actual climate crisis is forcing the development of new energy sources that mitigate the negative effects of the climate change. Because of that, the use of fossil fuels is expected to be significantly reduced in the coming decades. In this scenario, the production of renewable fuels that reduce the greenhouse gas emissions (GHG) is one of the main world challenges. The present study focuses on synthetic gas production using carbon dioxide from the cement industry, and green hydrogen, simulating the process us...

The article describes the approaches to development of an effective regulatory mechanism to manage carbon intensity of Russian resource-intensive industries. The authors focus their attention on the ferrous metallurgy industry as the top emitter of greenhouse gases (GHG) and the second-largest consumer of energy among Russian industrial sectors. Resource consumption wise this sector is well-studies and regulated by the Best Available Techniques (BAT). Establishing the interrelation between carbon intensity indicat...

This work delves into the process of phenolic oxidation products rdistribution in Nitisols Ferralic and Humic Cambisols, which were modified by (14C) introduced tea biomass. Metabolites derived from tea biomass were found to interact with humic and fulvic acids and form covalent bonds with them. The study of quantitative aspects of the inclusion of phenolic substances in the chemical composition of humic and fulvic acids reveals that humic acids incorporate a significantly greater amount of the radioactive tracer ...

In recent years the subject of reliability prediction of complex systems has become more significant because of increasing the criticality of the infrastructure. The present research refers to surveying the operation of pumping stations and problems encountered during the exploitation, as well as developing a reliability assessment methodology. The main causes of damages in pumping stations are analyzed according maintenance data from water supply and sewerage operators. Reliability assessment is based on the dete...

This review article provides an overview of the combination of remote sensing with deep learning techniques in the last ten years. It specifically examines the emerging patterns and applications in both fields, highlighting their combined use in processing remote sensing data. It focuses on how these techniques have brought about significant changes in environmental monitoring, urban planning, agricultural management, security, and change detection. The article discusses various satellite probes, detailing their s...

This study presents an review of the geophysical and geological data available for the Bulgarian Black Sea shelf, highlighting the methodologies employed for data storage and their effectiveness. Such data are crucial for understanding the shelf's historical dynamics and ongoing changes, serving as a foundation for various scientific investigations. Through an analysis of geological, morphological, geophysical, and geochronological data, we trace the evolution of the shelf's structure and movements, delineating it...

Food supplements with strong antioxidant potential are increasingly being used by consumers to maintain good health [1], [5], [6], [8], [9], [10], [11], [15]. The best food supplements use natural and organic raw materials and -Mild Food Processing- operations. This work paper presents a management technique for food additives (used, in this case, in the testing and selection of used sweeteners) in the design of a black tea-based food supplement. The raw material used was tested by A.A.S. (Atomic Absorption Spectr...

There are situations in which human health is at risk from inhalation of hazardous substances and particles (viral epidemics, biological weapons, chlorine leaks, nuclear accidents, asbestos removal, quarrying). In response to these scenarios, emphasis is placed on respiratory protection and minimising exposure to these substances and particles. One of the most commonly used respiratory protective devices is respirators. However, respiratory protection for children is not addressed by any manufacturing or testing t...

Whey is a significant environmental contaminant since its waste load is estimated to be 100-175 times more than that of an equivalent volume of household wastewater. It is estimated that around half of the whey produced is used for human or animal use, and the other half is released into the environment as waste water, which adds to pollution. Thus, in accordance with the guidelines established by the EU Green Deal Program, its valorisation through the development of health-promoting products is an important step ...

The explosions produced in industrial/chemical facilities, such as hazardous material storage facilities, are events with low probability but high destructive potential. When occurring in a densely populated area, such explosions can lead to extensive damage of nearby buildings or infrastructures, resulting in high economic costs and human injuries and fatalities. The explosions may be the result of an accident but may also be intentional. As the pressure released by the external explosions decreases exponentially...

This study investigates the adaptive strategies of farmers in the Todgha oasis, Morocco, as they respond to the pressing challenges of climate change. Through a mixed-methods approach, we assess the resilience mechanisms adopted to sustain agricultural production amidst increasing temperatures, unpredictable rainfall, and shifting ecological conditions. Key findings reveal that farmers rely heavily on traditional water management systems, including khettaras and modern pump-assisted irrigation, to mitigate water s...

The discharge emanating from a municipal wastewater treatment plant (WWTP) is a contributing factor to the pollution load within the adjacent natural water body. Generally, effluent constraints can be upheld during periods of dry weather. Nonetheless, instances of surpassing these limitations are common during storm events due to the substantial surge in inflow. The retention of incoming stormwater presents an opportunity to mitigate both quantitative and qualitative concerns. However, the spatial and financial pr...

One of the main monitored parameters related to road traffic safety is the visibility of road facilities and how they are perceived by drivers. Areas where visibility is suddenly limited, or where road sections become unclear due to inadequate design and technological arrangements, pose significant safety risks. Monitoring the optical properties of the applied coating surface, particularly its retroreflection and colour, is crucial for traffic safety. The paper describes research leading to the design of a system ...

The paper presents a theoretical and practical approach to the concept of risk assessment specific for the demolition of the industrial civil objectives with the help of explosives in terms of ensuring security premises for the effects generated following the blasting demolition work of this type of constructions. Blasting realization of industrial civil objectives to be demolished involves a series of operations that generate health and safety risks to economic operator employees which are carrying out work and f...

Assessment of non-carcinogenic risk for the child population health from chemical substances taken with the motor vehicle exhaust gases in 4 districts of the city of Kazan based on the monitoring data from FSFHI -The Center of Hygiene and Epidemiology in the Republic of Tatarstan- for the period from 2015 to 2021 was carried out. The average annual concentrations of chemical substances exceeded the allowable level of standards (MAC) from 2.32 to 9.96 of MAC in all zones. The value of the total daily dose on the in...

Based on the principles of prevention, the employer must seek to eliminate risk at source and, in order of priority, to replace hazards through non-dangers, to separate or isolate areas where there are hazards, ensuring adequate collective and individual protection. However, workers from high and very high voltage power substations continue to be exposed to occupational hazards, suffering accidents at work and occupational diseases with significant repercussions on their health, on colleagues or National Power Sys...

In this work, a rock fall assessment was carried out in two distinct areas in southwest Angola. One is located next to Chapel of Nossa Senhora do Monte in the urban area of Lubango. The other area is located on the road between the city of Lubango and the tourist area of Tundavala. The rock mass of the first area belongs to the Tundavala Formation of the Chela Group and consists of quartzitic-sandstone with a sub-horizontal bedding attitude. The rock mass in the second area is composed of quartzitic-sandstone and ...

There is a worldwide ecological problem of anthropogenic eutrophication. The problem is especially serious one for the ecosystems of lakes, water-storage basins, and closed seas, such as the Baltic Sea. The eastern part of the sea is the Neva Bay. The water area is totally located within the administrative border of St. Petersburg and is influenced by the megacity. There is monitoring of the total nitrogen and phosphorus inflow into the Neva Bay with water of the Neva River and its spill streams. Nevertheless, the...

In the period 2010-2022, Romania has seen a continuous increase in the share of renewable energy in gross final energy consumption, promoting and using green energy sources. In 2019, more than 24% of energy consumption came from renewable energy, ranking 10th in the EU, surpassing the European average, and by 2030, Romania aims to reach a share of 49.4% renewable energy in gross final consumption of electricity. In this perspective, climate change is the most discussed topic, and from the analysis of CO2 emissions...

The climate, energy, and health crises, alongside the conflict events in Eastern Europe, have generated new directions regarding the perspectives of global and national energy transition, by orienting it towards a decarbonized economy. The increased frequency of climate change-related weather events affects the availability of renewable energy sources (wind and solar) and energy supply security. The abandonment of fossil fuel-based electricity and heat due to commitments and objectives established in the United Na...

The roughness of a ship-s hull can have a significant impact on the environment, primarily through its effect on the ship-s fuel consumption and, consequently, carbon emissions. The resistance a ship encounters as it moves through the water can be broadly categorized into two main types: frictional resistance and wave-making resistance. Hull roughness increases frictional resistance, also known as skin friction resistance. This resistence component is a major aspect of the total resistance of a merchant ship, lead...

The relevance of the research lies in the fact that the well-being of the Ukrainian nation, present and future generations, largely depends on the preservation of existing ecosystems, their support, and the enhancement of their quality and biodiversity. Particular attention should be paid to the problem of land cover degradation. Land cover currently holds a unique status regarding food security and is a dominant source for renewing crucial biospheric functions, ensuring the diversity of living organisms. The anth...

The deep processing of lignocellulose feedstock (including waste from the woodworking industry, agriculture, and agro-industry) allowing the high-added value products to be obtained is one of the key scientific problems. Lignocellulose biomass is a potential feedstock for the production of heat, electricity, fuel, chemicals, and other bioderived products. The liquefaction is considered to be one of the most promising ways to convert lignocellulose biomass into liquid fuels. During the liquefaction, lignocellulose ...

The construction industry is one of the largest air polluters. This fact, along with the increasing demand for savings of heating energy, is leading to a growing interest in more eco-friendly materials for building thermal insulations. New thermal insulating material, prepared from the Posidonia Oceanica (commonly known as sea grass or Neptune grass) was prepared and studied. Posidonia Oceanica is an endemic plant that grows in large quantities in the shallow waters of the Mediterranean Sea. It is a protected spec...

The health, richness, and variety of microbial life in soil represent basic indicators for the evaluation and surveillance of forest ecosystem vitality. The vital role these microorganisms occupy in forest ecosystems underscores the necessity to in-depth assess and monitor their populations within soil habitats. Aiming to deepen our comprehension of microbial communities across different soils and soils horizons, we conducted an investigation of 22 soil profiles situated within the territory of Vitosha Nature Park...