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Pig breeding is a profitable activity for small and large farms, being currently influenced in an increasing extent, by the international competition in this area. As a result, pig breeders must keep pace with changing technologies and production techniques to maintain the competitiveness of their farms. Also, it is necessary to take into account the new European regulations, particularly those relating to the environmental protection, the comfort of animal and food safety. The objective of this paper represents t...

The microseismic monitoring is a method of monitoring of fracture propagation during hydraulic fracturing process. Hydraulic fracturing is a method of reservoir stimulation used especially for unconventional gas recovery. A matrix of several thousand geophones is placed on the surface of earth to record every little tremor of ground induced by fracturing process. Afterwards, the signal is analysed and the place of tremor occurrence is calculated. The detection of microseismic event is not trivial especially in noi...

In modified Tube reactor, where the average concentration of solids amounts to 0.1- 0.2 t/m3, i.e. the conditions for residence time are long enough for the thermal combustion of biomass waste and coal and extensive gas mixing with 60-70% excess air so enhancing biomass combustion and heat transfers to the boilers. It is necessary to create conditions of internal circulation without the transported coal and waste in modified Tube and boiler, 90-95% combustion yield were observed at the end of combustion. Total hea...

It has been statistically proven that tuffogenic sediments, especially tonsteins, have a negative impact on the incidence of pneumoconiosis (silicosis) among miners in French coal basin. Therefore, the rocks attract the interest of geologists not only due to their origin and possibility of use for correlation purposes, but also as a source of dust hazard in mines. The present publication presents mineralogical tests of inhalable grain size dust formed during the exploitation of a coal seam with a tonstein overgrow...

The Vanavar Formation is a terrigenous horizon (1 to 200 m thick) at the boundary of the Tonian-Cryogenian and Ediacaran-Fortunian carbonate complexes. The geological position of the Vanavar Formation and the intensive facies variability do not permit a clear characterization of the conditions for its accumulation. Additional interest in the study of Vanavar Formation caused by its oil-and-gas bearing deposits. The objects of research are the core samples selected from well ? 3 of Pridutsky area. The mineral and c...

This article discusses a comprehensive study of the sand samples, which were selected on the Arabian seashores (Kovalam, Kollam, Kerala, India), and produced ilmenite, zircon, garnet and monazite concentrates (Chavara field, Kerala, India). As a result of versatile research, realized in the laboratories of KFU, which represented mineral and radionuclide composition of the studied samples, marginally represented La, Yb, Hf. Discovered free of impurities zircon, as well as zircon of the hafnium species. The studies ...

Bitumen deposits in Permian sediments in the Volga-Ural region are interesting as sources of unconventional oil. The reservoir rocks in the bituminous deposits are sand and sandstone of varying degrees of strength. For the prognosis of productive areas, it is important to study the peculiarities of the composition of bitumen-containing rocks and the mechanisms of localization of oil matter in them. These processes are closely related to the conditions of formation of the surrounding rocks. We examined samples of b...

The demand for natural resources and the associated need for drilling works will continue to grow. This is mainly due to turbulence in the markets for trade and transmission of raw materials by pipelines between countries. In addition, the aim is to become independent from external supplies. Growing demand for natural resources (petroleum, natural gas, shale gas, etc.) will increase the volume of drilling works. They interfere directly with the environment at their place of performance. Through the use of new tech...

In this article the air infiltration through the envelope of a naturally ventilated building, located in Bra?ov (Romania) is studied. The paper presents the study of the factors which influence the air infiltration пїЅ wind effect and stack effect пїЅ and the modeling of air change rate (ACH) inside the building, by Multiple Linear Regression (MLR) modeling. It has been found that ?T can be a good predictor of ACH because of its high physically correlation with this. Another conclusion of the study is that althoug...

Year by year, the growth of the share of heavy oils in the total volume is steadily increasing. For development of highly effective methods for its processing, approaches to modelling their properties should be elaborated. This thesis is dedicated to deriving and substantiating a formula for calculation of the velocity field in the round pipe volume as adjusted for rheological features of the flow of heavy oil suspensions. The suggested approach is based upon rheodynamics equations reflecting the flow of a rheolog...

Forecasting of viscosity value in blending of oil products is an important production task, settlement thereof influence the selection of its pumping mode and a number of other technological aspects. Quite high-precision models have been offered for the objects similar in viscosity, but at significantly different value of viscosity for the mixture components there is a great error. Graphic diagrams of interaction of petroleum-bitumen suspension-kerosene mixture viscosity at various ratios of its components and var...

This article is considering anthropogenic and natural pollution, which leads to a change in global temperature. The article also talks about the Greenhouse effect and global climate change. The average global temperatures can fluctuate within years and even decades, for different natural reasons. The article analyses how the world pollution leads to a change in the global average temperature. The aim is to create a model that will show us the relations between the changes in global average temperature with the pol...

Asphalt-resin-paraffin deposits deposited in the extraction of oils considered difficult to recover are investigated. Specific features of asphalt deposition of resin-paraffin deposits, caused by different content of high-molecular components in them and their properties, are revealed. Redistribution of petroleum paraffin hydrocarbons and asphaltenes between oil and asphalten-resin-paraffinic deposits deposited from them is shown. The process of precipitation of high-molecular components from heavy oil under dynam...

The transit gas pipeline in Slovakia was built in 1970s. The gas pipeline runs from Ukraine through the southern part of the entire Slovak Republic to Czech Republic. The transit pipeline is made of 5 lines with diameter of 1,220 m and 1,420 m. Terrain obstacles such as rivers and water courses are mastered by 16 pipeline bridgings. Currently the lifespan of many structural parts is expiring. According to the long-term partnership EUSTREAM (pipeline administrator) and Department of Steel and Timber structures, Fac...

Compacting is an important technological operation when forming of earth fills and backfills, where appropriate earth stabilization and in the construction of highways and roads in the compaction of bituminous and other surfaces too. Compaction is technologies that occurs at the building during construction time. It should be optimally compress all of the individual layers of the respective construction works. The works must be carried out as precisely and as economically with the smallest number of crossings comp...

In paper the gas analyzers of new generation constructed on the basis of semiconductor sensors are considered. Application of the semiconductor gas-sensitive elements allows to solve the main objective of the modern gas analysis пїЅ detection of vapors and gases of the wide list with high stability, the necessary selectivity and sensitivity. The semiconductor sensors allow to find substances in air in a broad range: from trace concentration 10-6 - 10-5 mg/m3 to high 500 - 800 mg/m3, owing to their developed struct...

Sediments are usually regarded as the ultimate sink for heavy metals discharged into environment, and can be sensitive indicators for monitoring contaminants in aquatic environments. Therefore, the environmental problem of sediment pollution by heavy metals has received increasing attention in the last few decades in both developing and developed countries through the world. Environmental risk assessments, including sediment monitoring, are typical tools for supporting decision making in the regulatory context, an...

This study investigated the degree of heavy metal accumulation in fruits, leaf, shoots and associated potential health risks in agricultural areas of the Mitrovica city, northern Kosova. Total concentrations of lead (Pb), cadmium (Cd), nickel (Ni), arsenic (As), zinc (Zn), copper (Cu), chromium (Cr) and iron (Fe) were determined in soil and fruits, leaf, shoots apple tree with rootstock MM106. Samples collected from agricultural areas (near Mitrovica city), have been analyzed for heavy metals (Pb, Cd, Ni, As, Zn, ...

First part of the paper presents the monitoring project of Turdas tunnel with the detailing of the monitoring equipment. Building of Turdas tunnel was realized for ensuring the maximum speed of 160km/h for passenger trains. In order to build the tunnel was provided a provisional support and a final support, due to difficult field conditions, obtained from the geotechnical studies, because of the presence of the swelling soil. To achieve safe construction of the tunnel were mounted specific monitoring equipment in ...

For the bridges under rehabilitation, especially for cable stay and suspended structures, situations that can lead to the increase of strain in the structure may occur during construction works. Because of that, monitoring the way the bridges behave during works becomes necessary. Monitoring them during rehabilitation under traffic is essential, because alarms are triggered when accidental actions take place or when certain strain values are exceeded. The bridge on DN39 over the Danube пїЅ Black See channel in Agi...

Heavy metal contamination of soils is a long-standing environmental problem in the world due to the increase of anthropogenic impact on landscapes. The proposed paper is the first step of an integrated ecological and geochemical investigation of soil cover of the Baikal region. Study object is the biggest island of the Lake Baikal named Olkhon, which is a part of the Baikal National Park, Russia. The study was performed by the key-site method. The method is based on the revealing an index plot, which characterizes...

TV measurement monitoring and diagnosis of the state of heterogeneous biological media can be carried out on the basis of processing the array of multispectral images of the object obtained by the CCD camera at characteristic wavelengths. The biophysical and structural parameters of inhomogeneous biological media of different origin influence their spectral characteristics, in particular, the coefficient of diffuse reflection. The aim of the work is to increase the reliability of monitoring of natural biological m...

The mining industry is often faced with great difficulty in drilling deeper and deeper holes in the search for oil and gas. This results in constantly increasing costs and the continuing need to create better materials and technologies to reduce possible losses. Drilling technology must cope with high temperatures and pressures in the hole and other unfriendly environmental conditions. Increasing demands on the properties of the slurry and cement stone force the search for unconventional solutions and materials th...

In the placers of the south-eastern boundary of the Lyapin megaanticlinorium at the Subpolar Urals for the first time the relation of native gold with bismuth and telluride minerals was reliably established. The placer area is located within the Lower Proterozoic and Riphean metamorphic rocks. Directly in the placers Bi-tellurosulphides, tellurides and sulphosalts (tetradimite, joseite-B, joseite-A, tsumoite, hedleyite, cosalite), native bismuth, native silver, maldonite are determined together with gold in large ...

Proper estimation of geomechanical parameters of the shale gas reservoir has a crucial influence on the stimulation treatments designing and therefore on hydrocarbon production from unconventional reservoir. The brittleness is the most commonly used parameter for locating the geomechanical hotspots in the reservoir. This parameter can be estimated using elastic, dynamic rock properties such as Poisson Ratio and Young Modulus obtained from sonic logs. The seismic waves velocities recorded by the sonic logging tool ...

The paper presents three natural reserves in Romania: Dumbrava Vad nature reserve known as the Daffodil Meadow - Brasov County, is considered the largest reserve of this kind in Europe. Daffodil Meadow Negrileasa пїЅ Alba Country and Daffodil Meadow Negra?i - Arges County. For accomplishing the objectives of this paper were been created maps using Program ArcMap 10.1. The maps play a role to present the characteristics of the area in terms of geomorphology. The aim maps is to present this natural reserves in terms...

The present study aims an integrated risk analysis of existing or potential natural constituting a direct or indirect threat on the analyzed geographical area. These regularly processes cause lately extreme and significant disturbances in the primary and significant damage system components in various fields of economic and social life. With an inventory of all these dangerous phenomena may be proposed at local government levels, a series of joint measures on mitigation and combating the effects induced by natural...

One of the main objectives in real-time assessment of seismic hazard is the development of algorithms for rapid estimation of the seismic source parameters (fault planes solutions). The objective of this work is to test and implement new methodologies in the National Institute for Earth Physics (NIEP) for near real time estimation of fault planes solutions taking the advantage of the spatial density of the Seismic Network in seismically active zones ( 120 seismic stations used in real time) and the full range of t...

Over the last decades, deep drilling technology expanded fast. Newly created progressive technologies improved quality of drilling work and speeded-up the drilling process. Currently, 75-80 % drilling methods used world-wide are traditional, while 20- 25 % are new techniques. Slovakia is a little behind this trend: our utilization ration shows 95-98 % traditional drilling methods, compared to only 2-5 % new ones. Together with development of new deep-well boring technologies, new types of drilling sets for deep dr...

The paper proves the conditions for the transition to a new paradigm for the development of the Russian oil and gas complex. At present time, the structure of the resources base of oil and gas in Russia is fundamentally changing. This creates important conditions for the directions of innovative development. In the 21st century, the main new objects for exploration and production of oil and gas fields are: shelf in the Arctic Ocean; new undeveloped areas (Eastern Siberia and the Far East), unconventional sources o...

The main purpose of this paper is to investigate of the Ni?de Fault zone, which passes through the city of Ni?de. The study area located in the south and eastern part of the Ni?de Province, and crops out different types of geological units from Paleozoic to Cenozoic in that vicinity. These units are, from old to young, metamorphic rocks, which is known as Ni?de Massif composed of GпїЅmпїЅ?ler, Kaleboynu, A??gedi?i formations, пїЅпїЅkap?l? granodiorite (Paleozoic to Mesozoic), K?z?lkaya Ignimbrite (Upper Miocene to...

In this paper, we analyze almost ten years of continuous recordings (November 2007пїЅ April 2017) from 114 stations of the Romanian Seismic Network using the power spectral densities and their corresponding probability density functions (PSD PDF). For each vertical station component, we compute the statistical mode for noise levels from the PSD PDFs. The noise mode represents the highest probability noise level for a given station. We then construct the PSD PDF mode low-noise model for Romania (RONM) from the mini...

The investigation of the fault tectonics in the Kovdor carbonatite intrusion (NW Russia) has resulted in the identification of a new brittle deformations type. It is formed due to the simultaneous turn of fissure planes at discrete angles around two orthogonal guiding lines (axes), where one is represented by a vertical massif symmetry axis (L1), and the other axis (L2) lies horizontally in the fracture plane. Nonetheless, the rotation along the both axes is codirectional, i.e., when moving counterclockwise around...

The work is devoted to the West Siberian sedimentary basin Bazhenov formation (or Bazhenov shale) пїЅ a unique oil-generating and oil-bearing geological formation. Bazhenov shale is an analog of the known shale oil deposits: Bakken, Eagle Ford and Monterrey (USA). Geological and geophysical exploration of bazhenites is an important problem today, which is connected with development of new methods and technologies of unconventional oil and gas reservoirs exploitation. The work is devoted to physical and chemical pr...

This paper presents the dynamic investigations on the response of important building from Craiova, the University of Craiova. This building was affected by the major seismic motion from March 1977, 1986 and 1990. The processing of the data obtained through this investigation gives important conclusions on the influence of the major seismic movements of a specific type of structure. The main degradation of the structure was observed using noninvasive testing. This building with high importance was tested using dyna...

The flourishing of the family Orthidae (class Rhynchonellata, order Orthida) was happening in the first half of the Ordovician, the stage known in the literature as the Great Ordovician Diversification. The problem of the establishment of the Biodiversity centers is one of the dominant problems of modern Evolution Biogeography. At the present time, there are not common criterions for the determination of biodiversity's center in spite of the unanimous acknowledgement of the existence of local speciation's regions....

Compact fuel processors based on steam reforming process using natural gas, liquefied petroleum gas (LPG) and biogas have been developed for over a decade in order to offer the fuel gas (hydrogen) into the combined heat and power (CHP) fuel cell systems for cogeneration of electricity and heat. Numerical modelling of a steam reforming reactor described by fully coupled mass, energy and flow equations was developed in this paper by using the Finite Element Method (FEM) based Comsol Multiphysics software version 5.2...

Innovative aerobic granular sludge (AGS) technology has proved its ability to remove organic pollutants and nutrients from wastewater treatment at the same efficiency, but at a lower costs than conventional biological process. This technology has been successfully applied in sequencing batch reactor (SBR) configuration. An experimental model bioreactor was designed for adapting the AGS technology to continuous flow conditions. This paper presents numerical results for hydrodynamics and air dispersion into bioreact...

Frequent alternations of high and low temperatures and of rainy and dry weather, which were increasingly felt in recent decades have reduced harvests. Thus, the identification of varieties with genetic characteristics that provide a better adaptability presents a particular importance. Although a cultivar is known as the most important technological link in terms of production stability, the quantity and quality are influenced by the climatic conditions. Observations were conducted in the experimental fields of th...

In post-mining areas appearance of uncontrolled mining gas exhalations can be observed. Methane migrating through the strata, together with soil air may create explosive mixtures. Occurrences of mining gases are caused due to discontinuation of water pumping process in abandoned mines and fast rising and restoration of water table. However, itпїЅs not obvious, that all hydrocarbons in soil pores come from abandoned hard coal mines. Often in soil pores mixtures of microbial and thermogenic gases are observed. For i...

The dynamic development of material and chemical engineering as well as physical analytical methods allows the use of new materials for the production of drilling muds. This is especially important because drilling works are conducted in increasingly difficult geological and technological conditions. The present analyses concentrate on the development and elaboration of recipes of drilling fluids with organophilic nanomaterials. One of the most frequently applied nanomaterials referred to in patents registered by ...

Today, as a result of the depletion of low- and medium-density oil deposits, the world faces the problem of increasing oil production by involving non-traditional, alternative sources of hydrocarbon raw materials, which include fuel shale. In the area of the Volga-Ural oil and gas province, tight shale hydrocarbons reserves are located in domanic sediments. Quantity and spatial distribution of organic matter of domanic species remains underinvestigated. Assessment of oil potential, generation of mobile hydrocarbon...

Design of a structure together with monitoring the structural response to dynamic loads (seismic and hydrodynamic), fatigue aging, the possibility of successive degradation, resilience respective vulnerability are strongly influenced by the chosen calculus model, and a laborious probabilistic calculation. For particular case of offshore structures this implies the connection between the actions of the environment: wave histograms, wind action, foundation collapse, structure, technological activities and so on. Als...

The article presents the materials of long-term research conducted from 2004, in the mouth area of the Northern Dvina River. The program of researches included determination of concentrations of mercury in the water, covering about 150 km of the river length. We also analyzed such parameters of water as pH, Eh, oxygen content, salinity. A long observation period allowed us to trace the peculiarities of the changes of mercury content in water, which was the aim of the present work. Previously the authors determined...

The energy sector is an essential component in any nationпїЅs economy and well-being. The security and safety of any energy grid system is nowadays a strongpoint in mid and long term strategies when it comes to national development. Safety and security of energy supply is a multicomponent factor that includes: power generation systems, power transport and distribution systems and consumer management. The power generation units in Romania are very complex and they include different sources like coal, gas, nuclear, ...

The emergence and development of the internal combustion engine began in the 18-th century in England. But the first patent for a piston engine with compression ignition was achieved by Rudolf Diesel in year 1892 [1]. The engine use coal powder as fuel. The most used vegetable oil as a fuel and peanut oil. In the year 1859 in Pennsylvania was first released at the amount of crude oil that has been refined for kerosene and gasoline. Because a large quantity of by-products remained unused, Rudolf Diesel using a frac...

Countries that largely base their production of electricity and thermal on coal, are exposed to a significant burden of the environment, mainly through the emission of harmful substances into the environment, including the production of large quantities of solid waste: including fly ashes, slags, ash, slag mixes etc. However, the waste generated in combustion processes does not have to be a burden to the environment. Due to the changes in legal regulations they may become a by-product (i.e. Coal Combustion Product...

Costs in mining and extractive enterprises is a critical factor for competitiveness. The reason is enormously expensive equipment and technology associated with this type of business. It is therefore necessary to identify the so-called critical cost type, not only in enterprise but also in the entire industry of the country. Slovak Republic, calculated on an area, belong to one of the world's mining superpowers and take leading positions in mining of selected types of raw materials [6]. Mineral resources are the b...

In this article questions of increase in effectiveness of the equipotential method (its adaptation) for a research and monitoring of karst processes are considered. Authors carried out the analysis of the principles of creation of systems of monitoring on the basis of the equipotential method. Mathematical justification of formation of compensation signals for sensitization of the applied equipotential method is given in work. Algorithms of the regression analysis for increase in reaction of system of monitoring t...

The article deals with optimizing CFD model of the gravitational heat pipe to the creation of substitute materials and the optimization of its properties, depending on the actually measured results of the experimental device. Gravitational heat pipe operates on the principle of phase change working fluid (heat transfer fluid). The very principle of heat transfer is based on the theory of evaporation and condensation of the working fluid (heat transfer fluid). Heat pipes are classified according to the method of op...