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The materials used for the synthesis are modified waste raw materials in the form of slags (up to 70 % wt.) with addition of quartz sand and calcium fluoride. The initial batch is being melted at 1400 oC and then quenched in water. The resulting glass frit is milled bellow 75 microns, pressed into “green” samples being exposed in a next stage to thermal scanning at different temperatures with different heating rates, holding temperatures and times. In the framework of present investigation is presented analysis of...

A severe problem affecting urban areas is a large number of stray animals, either r eject- ed by their owners or born in the wild. These animals face the problem of malnutrition, as it is difficult for them to obtain food without human help in urban conditions. The fact that shelters are overcrowded is not suitable for these animals as well well. In o rder to protect them from the tragic death of starvation, the authors decided to de- velop an intelligent system for feeding stray animals. The system makes it possi...

The processes of liquefaction of water-saturated soils under dynamic impacts are one of the many negative and destructive geological processes and phenomena that constitute the geological hazard in Bulgaria. Processes of liquefaction of water-saturated sediments on the territory of Bulgaria are registered during almost all strong earthquakes affecting its territory from both local and regional sources. Specific cases have been described by a number of authors. These processes lead to loss of bearing capacity of wa...

In this paper, a class of multi-extremal stochastic programming problems is considered. Direct and dual problems are also included in this problem, respectively, in this paper the question of the existence of solutions to such problems is studied, the necessary theorems and proofs are given. Decision making under uncertainty is based on the fact that the probabilities of various scenarios are unknown. Decision-making under risk conditions is based on the fact that each situation of the development of events can be...

The development of urban areas, transport, and technical infrastructure is one of the natural phenomena that have been going on for several centuries. In recent years, due to migration population in many developed countries occurs a rapid increase of impervious areas in urban agglomerations. The rapid development of an impervious surface can cause changes in the hydrological and climatical characteristics of the area. As a result of these changes, surface runoff is creating. Surface runoff is an area source of pol...

The Vrancea zone, located in Romania, at the sharp bend of the Southeastern Carpathians, is a well-defined seismic region in a continental convergence area with unique properties and generating the most destructive subcrustal earthquakes in Europe. The seismicity is concentrated in a confined, high-velocity, focal volume at 60–200 km depth range. The increasing number and quality of waveforms digitally recorded in the last time by the National Institute for Earth Physics (NIEP) provide the opportunity to better co...

?very year, forest fires tens of thousands occur in Russia, as which result in more than 1 forest a million hectares are burned. At the same time, and even forest larger amount is damaged, and later perishes. For example, thermal radiation from a fire front directly affects a tree cambial layer, and this leads to its death. Also, due to the heat transfer of heat to the soil, its chemical composition and structure, microflora and soil change fauna, and the trees surface roots are damaged. Damage from forest fires i...

Precision management of the crop production, implemented in the precision farming system, implies a spatially differentiated, based on spectral measurements, implementation of agrotechnical measures provided for by the technology of their cultivation. The study of the spectral characteristics of spring wheat crops under changing agricultural conditions was carried out in a multi-factor micro field experiment at the Menkovskaya experimental station of the Agrophysical Research Institute (Russia, Leningrad Region). ...

The determination of residual oil reserves is a complex task that involves high qualified specialists and resource-intensive calculations. Classical oil reservoir simulation methods cannot provide proper level of reliability due to increasing of complexity caused by oil reservoir depleting. Stagnant oil zones arising from heterogeneity of shear modulus of medium cannot be determinate by oil reservoir simulation due to use of effective values of porosity and absolute and phase permeability. The problem of determina...

Modeling is important for river system analysis and management. The aim of the research is to apply disaggregation models to data with recovered natural river flow of Osam River located in North Bulgaria. As a result river discharge synthetic sequences are generated on monthly and seasonal discretization. We want to test applicability of the models for specific climatic, hydrological and orographic conditions in Bulgaria. Disaggregation models are from the family of stochastic models. Disaggregation models could b...

Globally, modern crustal movements are being studied as a priority, a large number of projects are being developed and significant funds are being allocated for the development of research in this field of science. Due to the social importance of the problem, the need to obtain geodetic data on the current activity of the earth's crust is realized. This article examines the study of the temporal movements of the earth's crust and the accumulated stresses in a geologically and seismically active region with the pre...

The efficient use and recycling of industrial water is a major challenge to the sustainability of the planet. Blast furnace slag is a by-product of metallurgical operations during the production of cast iron. The granulated slag is obtained by cooling in water. In this research we studied the cooling water of granulated slag generated from the process of making cast iron through the blast furnace route. The elemental analysis of granulated slag and of granulated slag stored in water was determined by X-Ray Fluores...

Waste steel slag is a major source of environmental pollution within the metallurgical industries. Metallurgical slags like blast furnace slag, ferroalloy slag, converter slag and copper slag are produced as by-products in metallurgical processes. During the production of steel, one ton of slag waste is generated per every three tons of stainless steel produced. In order to reuse waste steel slag, discharged at high temperature range (1250-1650 °C) and cooled in water, which is named as granulated slag, three diff...

In the current work, the process of fermentative conversion of animal waste and non-hydrolized plant materials (peat) using food waste and ascorbic acid salts as a stimulants is described. The amino acid composition of the biofermentation products was estimated. The possibility of the target biosynthesis for the production of fertilizers and feed additives with the pre-determined properties was recognized. It was shown that the additive of bread making waste with the concentration of 10 wt. % increases the amino a...

To preserve and increase the biological and landscape diversity, it is necessary to have comprehensive information about the conditions and dynamics of changes in the study object, a specific local ecosystem. Nature reserves are created to restore habitats, to protect endangered species of flora and fauna, vulnerable or complex species. Particular attention should be paid to the study of wetlands, a stabilizer of the hydrological regime of ecosystems, and a shaping element of the regional climate. It is proposed t...

One of the significant problems in terms of the mining impact on environment is abandoned (due to various factors) deposits and tailings accumulated on landfills. In addition, one of the most important resources for the development of mining is the inclusion of raw materials (as non-industrial stocks) in the economy. There are two ways to solve these problems: a) to achieve economic profitability of the deposit by improving the technologies of extraction and processing of basic raw materials, and b) to develop inn...

The physical and chemical properties of fine sock filter dusts have been studied. It has been demonstrated that a part of the titanium is bound in hard-to-open anosovite that can be enclosed in a shell of amorphous silicon dioxide. Anosovite can be attributed to the phase that is radiographically characterized as the system Fe = Mn - TiO. It is noted that some of the anosovite particles are in a shell of silicon and zinc oxides, and a part is in a shell of silicon, zinc, and lead oxides. The silicate base of the e...

The NAO index has a strong influence on weather over West Europe and the Mediterranean basin but less prominent over the east part of Europe. The aim of this study is the assessment of the influence of the North-Atlantic oscillation on the snow cover conditions in Bulgaria. The winter (December thru March) station-based index of the NAO is used for the current survey as well as data for snow cover maximums from 10 meteorological stations, 4 of them mountainous, for the main period 1930-2020. The linear relation be...

Inhibition of the coil-helix transition of gelatin and retardation of the gelation process of the system as a whole is an important scientific problem. The solution to this problem will make it possible to maintain the properties of gelatin solutions for a long time without changing their rheological characteristics. In this work, by the method of dynamic mechanical analysis, the dependences of the time profile of gelatin solutions depending on the concentration of 10, 13 and 16 wt.%, as well as the different diss...

In the paper the authors present the study results of rock massif fracture based on the case study of a rockburst hazardous Khibiny deposit. The authors have revealed peculiarities in seismic process at different mining stages over a five-year period. The principal aim was to study the particularities of seismicity occurrence when the deposit is mined by approaching fronts, namely, in the periods between bulk blasts in the docking sections between them. The authors have proposed an approach to reveal the features ...

Oil is produced in the form of an oil emulsion due to the high depletion of deposits and significant water cut in wells. The formation of emulsions can lead to a number of complications in the operation of various field equipment, and sometimes even to emergency shutdowns or failures. Therefore, the study of the properties of demulsifiers and their effectiveness is an important task. The work investigates the surface-active properties of seven industrial demulsifiers produced in Russia, such as: interfacial and su...

Environmental problems of mining industry are largely related to the need to store mining and processing waste, occupying large areas and being a source of the natural environment pollution. The Mining Institute KSC RAS has substantiated the methodology and developed the technology for the ecological restoration of lands disturbed during development of georesources in the framework of the rock – biota system evolution by creating a sown cereal phytocenosis without the application of a topsoil layer, which provides...

In this paper was used correlations between LST-NDVI, for warmest day, for 2013-2016.Study area, Iasi, is geographically situated on latitude 47 degrees 12 min N to 47 degrees06 min N and longitude 27 degrees 32 min E to 27 degrees 40 min E. The largest city ineastern Romania is Ia?i and the seat of Ia?i county. Land surface temperature, calculatedfrom remote sensing data is used in a lot of fields of science, like: climate change,hydrology, forestry, urban planning, oceanography, agriculture etc. In earlier therm...

The paper presents some aspects of an experimental research in which basic recipes have been designed in order to obtain innovative products to be used in construction as finishing coatings. Starting from sunflower seed shells, considered a waste rather a by-product resulting from the industry of edible sunflower oil, and also from rough sheep wool, an animal waste from the zootechnical field, and also from the specific thermal insulating characteristics of theese two waste materials, a serie of basic recipes was ...

Old closed uranium mines can be a significant source of environmental pollution and hazards to human health. The problem could become more severe in time due to erosion if the restoration measures are not properly maintained. There are many uranium mines in Bulgaria that, even closed in the 1990s, could be a pollution source for surface and groundwater in their region. Through hydraulic connections, they can contaminate the rivers passing nearby. The aim of the present work was to check the hypothesis of a possibl...

Soil erosion is the most serious soil degradation on the territory of Bulgaria. Estimated average annual potential soil loss from sheet water erosion in Bulgaria amounts to 902.5 million tonnes. Over 68% of the territory of the administrative region of Kardzhali (East Rhodopes) is characterised by risk of sheet water erosion exceeding 100 t/ha y. The paper presents assessments of susceptibility to erosion of soils in the catchment of the Dzhebelska River (Eastern Rhodopes). The assessments are based on the USLE ap...

The purpose of the research was to develop an algorithm for a comprehensive assessment of the sustainable development of a mining enterprise based on an integral indicator from the standpoint of environmental performance and test it on the example of the largest Russian coal and energy company SUEK. In modern conditions the Russian energy sector is in a state of transformation, which is associated with the strengthening of globalization processes, tougher competitiveness and management of production systems. Moreo...

The effectiveness of rhizobia-legume symbiotic interaction is under the genetic control of macro- and microsymbionts. Both symbionts exhibit high level of genome/genome specificity interaction which is reflected by symbiotrophic indices vary significantly. Virulence and plant dry mass increasing are indices widely used in order to reveal well matched rhizobia strain and variety of legume host plant for practice demand. The aim of the research was to study how allelic polymorphism of symbiotically significant genes...

Operations carried out within the oil and gas industry involve the risk of explosions which might lead to work accidents with significant consequences for personnel and installations. The release of a hydrocarbon gas due to various reasons such as improper selected equipment or its’ malfunction, staff negligence, lack of maintenance a.s.o. in mixture with air generates a potentially explosive atmosphere if the mixture’s concentration ranges between certain limits, the so-called Lower Explosive Limit (LEL) and Uppe...

Unlike friable rocks, salt behaves pseudoplastic when blasted, which leads to other premises of the blasting technique compared to those applied for stratified sedimentary or eruptive rocks. Here can also add the salt inhibitory character on the thermodynamic parameters of the explosions, with effects on their efficiencies as well as some particularities of the execution of the blasting works due to the presence of methane gas in the salt mines. The article presents the results of the research carried out in fired...

Activity of many industrial enterprises is accompanied with considerable amount of liquid technogenic waste products containing toxic heavy and non-ferrous metal ions as well as petroleum products, oils, and surfactants that are discharged to surface water together with waste water and used technical solutions. Therefore, efficient wastewater treatment is one of the main directions to decrease the industrial negative impact on the environment. The main sour?es of wastewater pollution with heavy and non-ferrous met...

QDaedalus systems are currently used for astronomical observations to obtain astrogeodetic vertical deflections (VDs). Astronomical observations cannot be made under the same conditions as geodetic observations (e.g., GNSS), because meteorological factors (e.g., cloud cover during observation, high humidity, fog, etc.) and timing of the observations may directly affect the observed benchmarks, particularly regarding precision and accuracy determinations of the VD components observed with the QDaedalus system. For ...

The problem of the antibiotic resistance of bacteria inhabiting the guts of poultry and livestock and furthermore manures and fertilizers prepared from manures is recognized as one of the most serious problems in agriculture. Composting is described as an effective way to reduce the abundance of antibiotic-resistant genes in the final product, however such a positive effect is not always guaranteed. The addition of highly porous components like biochar into composting mixtures is applied nowadays in order to impro...

Today's society encounters cyber attacks on the energy sector not only on a theoretical level but unfortunately also in reality. The total number of cyberattacks is still rising, despite the ever-evolving defense against them. The article contains an overview of the largest cyberattacks in history on the energy sector and ways to carry them out. A cyber attack is a situation where a hacker or their group tries to gain access to key information or elements of the infrastructure. These can be power plants, their con...

Among its activities, the construction industry has a significant impact on the environment. In recent years, therefore, emphasis has been placed on the sustainability of building structures and materials, and ways and means are being sought to achieve this. Specifically, it is about reducing emissions and using the waste produced by recycling materials, e.g. aggregate. The motivation for using recycled aggregates is also to reduce dependence on natural resources, which are declining. The article deals with the as...

Due to the ever-growing importance of resource conservation and sustainable lifestyle, people are searching for new, alternative solutions that will enable a more sustainable use of resources. Because energy production is one of the most pollution-intensive industries, a major factor is renewable energy, which reduces the amount of industry pollution and facilitates sustainable use of resources. One of the sustainable energy resources are Salix and the wood chips produced from them, which are used in energy produc...

The aim of the study is the evaluation of multispectral imaging by unmanned aerial vehicles (UAV) and free available satellite data (Sentinel — 2) for the diagnosis of the nutritional status of winter wheat. For this purpose, a field trial was established in 2020 (28 ha of winter wheat), both on the fields of farm enterprise ZD Kojcice (Pelhrimov, Czech Republic). The observation of the fields was performed in two vegetation phases important for the application of nitrogen fertilizers to cereals by topdressing (BB...

The mitigation of GHG emissions from anthropogenic ecosystems is one of a challenge for following decades. Successful GHG emission mitigation scenarios can be developed if there are tools to predict GHG emission trends according to climate, soil conditions, farm management practices, and other factors. One of the essential GHG emission sources is managed agricultural soils, and the most important factors are soil conditions, soil moisture, and temperature. The conceptual hydrological model METQ has been created un...

Adaptation of materials of Internet resources is the provision of relevant content with maximum consideration for the individual characteristics and needs of the user. Thus, the system developers are regularly tasked with showing users the information that meets their tasks and interests, paying attention to the moments that really have value for certain categories of users. This article is devoted to one of the options for solving this problem. The article discusses the construction of a matrix-graph model for pr...

The use of information and communication technologies has many benefits. Based on many studies, their level is not sufficient. This can be caused by several factors and obstacles. Communication and ICT competencies are one of the key factors for the active use of advanced technologies for the management of sustainable construction projects. This digital age requirements systematic communication and project management. In this pandemic time, it can be considered an even more important requirement. It is the level o...

Annually, worldwide the food industry generates huge quantities of plastic packaging (polyethylene, polypropylene, polystyrene, polyethylene terephthalate, etc.) and due to their chemical structure takes hundreds of years to degrade, thus creating major environmental problems. Therefore, the aim of this study was to develop biodegradable films that can be used for food packaging and to identify their physical and mechanical properties. The biodegradable films were obtained using 150 ml Milli-Q water and different ...

The Danube-Black Sea Channel, inaugurated in 1984, although it has a dark history, is also of significant importance at European level, being the third longest navigable channel in the world, after the Suez Channel and the Panama Channel and connects the North Sea to the Black Sea through the Rhine-Main-Danube Channel, shortening the route of goods transport from Australia to Central Europe by 400 kilometers. The channel has a total length of 95.6 km and consists of two branches, a main one having 64.4 km long and...

This article describes gas hydrates formation, with methane and carbon dioxide as guest compounds, in a small-scale experimental apparatus, appositely designed to reproduce marine offshore reservoirs. The sediment consisted of pure quartz porous sand impregnated with FeSi3 particles, which are produced via gas-atomization and are usually destined to applications in additive manufacturing. Experimental results were compared with the theoretical equilibrium conditions for both types of hydrates. It was established t...

The hydrogenation of carbon dioxide (CO2) to methanol in presence of nanocatalysts has been reported as the one of the most economical and effective ways to reduce CO2 emissions. Over the past several decades, numerous efforts have been made to develop effective catalysts for CO2 hydrogenation to methanol. Among these, the CuO and ZnO based catalysts were highly active for methanol synthesis. Many studies have shown that SBA-15 (Santa Barbara Amorphous or mesoporous silica has good application prospects as a catal...

Training and development are a learning process that offers new and existing employees to acquire technical knowledge and skills and behavioral development attitudes so that their work is as effective as possible. Given the importance of staff training, this research measures the effect of training on the performance of employees of commercial banks in Kosovo, an important factor given that the growth and development of any organization is linked to the development of human resources. Quantitative methods used to ...

The European Green Deal is one of the attempts to make our economy more sustainable in the long run, and these issues have been increasingly raised in Latvia over the recent years. Promoting changes in daily food consumption habits could also improve people’s quality of life in the future. In a globalized food system, small and local businesses are often being pushed out of the market, which is divided between the big producers and food chains. However, food is also part of each country’s unique cultural heritage ...

Solid-state dissolution by sintering in the presence of Na2O2, a strong oxidizing agent, isreported in the present study as a preparatory procedure prior analysis by ICP-MS. Theadequacy of the combined procedure for the purpose of identification of potentialsecondary sources for REEs from difficult matrixes like, for example, mining wasteswas investigated. The method was applied to Certified Reference Materials (CRMs)with silicate-rich complex matrices, namely rhyolite, and granite. From each materialtwo sample we...

Terrain mapping has always been a process that ensured the economic development of countries and regions of the world. This was achieved due to the well-coordinated work of geodesists who receive geodata and cartographers presenting these data in the form of a cartographic image. For many centuries, the main task of cartographers was to accurately show the location of objects and their main characteristics using map symbols and cartographic methods. In the XX century, ideas about the essence and content of terrain...

Cadastre and Land Registry for Alba County in relation to the other counties of our country. Alba County is made up of 78 administrative territorial units, in which, within the framework of the programme, systematic registration works are carried out, both at cadastral sector and at ATU level. The works have been and continue to be financed from the own revenues of the National Agency for Cadastre and Real Estate Advertising (ANCPI), through the Office for Cadastre and Real Estate Advertising (OCPI) of Alba, but a...

The economic development of the Arctic region is a priority for the Russian Federation in the coming years, and this creates new challenges for Russian science in developing technologies and devices that can reliably and effectively function in the harsh conditions of the deeply negative temperatures of the northern territories. The paper examines the basic principles of low-temperature operation of molecular-electronic devices for recording motion parameters and wave fields, namely, the step-by-step operation of ...