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Synthesis gas for an electrochemical generator was produced in a thermochemical reactor with autothermal air conversion of methane (natural gas). Based on thermal balances of the reactor, a battery of SOFCs and a boiler-utilizer (BU) for heating primary and secondary air, cathodic air and methane, the following parameters were calculated: temperature at the anode, EMF of the fuel cell, electrical efficiency (gross) of the electrochemical generator, portion of hydrogen oxidized at the SOFC?s anode and specific cons...

The aim of the project is to determine the optimum geometry and different kinds of nozzles location on the drilling tools face. The optimum geometry and its proper arrangement will allow the maximum use of specific mechanical energy drilling through its reduction and minimizing pressure losses to overcome flow resistance in the nozzles of a drill bit. In their previous work, the authors showed that hydraulic power is a very important aspect, affecting the loss of pressure at the bottom of a borehole. It has been s...

The goal of this project was to create a detailed model of the Aral Sea sedimentary cycles. Modern methods of image processing and wavelet analysis were used to reveal the nature of lamination and determine the average and interval sedimentation rates. The results obtained were then compared with those from the radiocarbon dating. The images used in this project are photographs of core (sediment) samples taken with hollow plastic tubes. The samples were removed from the tubes by cutting them in half lengthwise, an...

Lately, high penetration of intermittent renewable energy sources into power systems requires, besides efficient technologies employment, developing adequate control strategies to improve their performance. Given that their operation flexibility is constrained by short timeframe of foresight, energy storage systems represent an attractive solution that can mitigate the natural variability of renewable power plants electricity output, providing therefore enhanced quality of supply. The nonlinearity and uncertainty ...

Granular sludge aerobic technology (AGS) has been extensively studied in recent years because of its advantages compared to activated sludge technology. Currently, this technology is implemented in SBR (sequential batch bioreactor) configuration. An experimental model bioreactor was designed for adapting the AGS technology to continuous flow conditions. It consists of a rectangular shape bioreactor, an area for pre-settling and recycling of granules, followed by a settling tank. This configuration is more suitable...

The anaerobic fermentation of biomass in methane-tank during the biogas production is considered. The process of individual bubbles lifting upwards and its simultaneous interaction with solid particles with mixing of the nascent substrate is analyzed. The forces acting on the bubble are given and a differential equation is developed that characterizes the biogas bubble movement in the organic mass substrate. The mathematical dependence of the flooding rate of the biogas bubble is developed and an example of solvin...

Hillslopes comprise the greater part of the landscape and as an integral part of drainage basins; they provide water and sediment to water courses. Also, hillslopes are frequently used in agriculture. Soil erosion caused by water is a natural phenomenon, but the negative effects are accentuated by human interventions in the landscape. Soil erosion and nutrient loss are detrimental to agricultural products, food security, and the sustainability of ecosystem functioning. In recent decades, the increased using of che...

The article presents a way of identifying and modeling sound features in an urbanized environment. The subject of article is focused on the problem of noise pollution modeling coming from moving technical objects, i.e. vehicles that are potential sources of noise. In this case, the vehicles are treated as multi-source acoustic energy emission objects. The proposed approach assumes the occurrence of variable relations in the system: source-path propagation-receiver. In the presented method the information carrier i...

At the age of an increasing demand for energy we reach to an ever wider range of substances giving a possibility of its generation. A constant need for energy supplies is so strong that we are not prevented by the danger related to the storage or transport of such substances. Although we try to eliminate any risks, even a small human error may contribute to a tragedy. In the case of substantial and sudden depressurization it is impossible to conduct in situ tests at a large scale. An attempt at conducting an in si...

The finite-difference method is used to compute small local deformation of the rock slope instability Alpe di Roscioro, Switzerland. This retrogressively unstable mass failed multiply, with last large catastrophic event in 2012, when approximately 210 000 cubic meters of rock had collapsed towards Preonzo village. The remaining mass has been studied and monitored by passive seismic methods and exhibits strong directional spectral amplification. One of the monitoring seismometer detects many micro-deformations and ...

The paper describes a mathematical model of the global crisis influencing the world economy. The model is based on four conceptual positions of modeling: the level of economic development of the global economy is estimated by the system of endogenous variables; there is the interdependence of endogenous variables; there is a process background for the endogenous variables; there are certain harbingers of the crisis determined for a specific endogenous index. The model is presented as a system of three interdepende...

Major genetic concepts currently existing in geology are based on the hypothesis of the Earth?s cold homogeneous accretion put forth in the mid-20th century. The data obtained in the last decades are in conflict with these concepts. It has been found that compositions, isotope ages and formation temperatures of the crustal and mantle rocks are interrelated according to the laws of magmatic differentiation. This indicates that the rocks formed as a result of fractionation of the global magma ocean. Chemical disequi...

Geophysical exploration, the necessary part of oil and gas exploration, generates more and more data, subject of processing. The most powerful super computer clusters are used by business and academic institutions. However, often it is necessary to have evaluation of the measured data shortly after measurements, even in the field. Modern computer architectures, namely Graphic Processing Units (GPUs) and Field Programmable Gates Arrays (FPGAs) provide a good basis for PC-based fast data processing, to have, say, su...

The integration of a building into the environment can be achieved both from the architectural point of view and from the point of view of the used building materials, thus remarking material used since ancient times, namely wood. Wood is an organic, sustainable, environmentally friendly material that can reduce carbon dioxide emissions Due to the latest environmental protection requirements, economic issues related to construction costs and architectural diversity, it has been necessary to develop technologies re...

The paper is devoted to construction of the time efficient algorithm for solving the structural inverse gravimetry problem. The problem is in finding by known gravitational data multiple interfaces between layers with different constant densities. This problem is described by a nonlinear integral equation of the first kind; so, it is ill-posed. After discretization of the area and approximation of the integral operator, the problem is reduced to solving a system of nonlinear equations. An efficient method was cons...

The diversity of ecosystems in the mountainous regions is generally higher than in the lowland territories. In this regard, there is no exception to the Caucasus region. The central part of the Greater Caucasus Mountain System, which is located within the Republic of Georgia, consists of fiveadministrative units (Mestia, Lentekhi, Tsageri, Ambrolauri and Oni) and is 3 historic-ethnographic provinces (Svaneti, Lechkhumi, Racha). The study area is 8157 km 2 and the hypsometrically ranges from 315 m to 5203 m. Our re...

Twenty eight onshore mud volcanoes of the Kerch-Taman province were analysed to evaluate their current contribution to the trace-element budget of the landscape. The study area belongs to the Indol?Kuban Trough, where the anoxic marine mudrocks of the Maykop Formation were deposited in the Oligocene ? Early Miocene in the northern deep-water margin of the Parathetis ocean. The Maykopian Fm. mudrocks are main sources of solid matter for numerous mud volcanoes of the region. Mud masses (30 samples) and mud volcanic ...

The article deals with the problem of restoring the disturbed balance in the system of ?man-society-nature?. As one of the factors the values of mythological consciousness are proposed. Myths and legends represent the experience of many generations of harmonic and healthy coexistence of man in nature. People became conscious of the environment through myths. The contradictions of man?s impact on the environment are investigated. All contradictions are based on technology and mismanagement of resources. Human impac...

The structure of the emptiness space of the oil reservoir rocks has been studied using high-resolution electron microscopy methods. Particular attention is paid to unconventional oil and gas reservoirs, among which argillites are finely divided. In them, the share of the nano-emptiness space is much higher than in typical carbonate and terrigenous reservoirs. The presence of a significant number of nano-cracks, which are either a continuation of micro-cracks, or independent of them, is established. A certain amoun...

First indication of habitation on the site of the future Halmyris fortress dates back to early 6th century BC, when the region was inhabited by the Getae. The Roman fortress, constructed in 2nd century AD, was the easternmost one in the chain of fortifications built under Roman occupation along the Danubian border of the empire and was abandoned in 7th century AD after it lost its economic and strategic importance. The site is located on Murighiol-Dunav?? promontory 2.5 km east of Murighiol village at around 1.5 k...

An analysis of the stratigraphic positions of the Neogene coal facies in Romania and in the countries around lead to a first cyclo-stratigraphic coherent scheme for the Neogene in the Central Paratethys (?icleanu et al., 2001). This was based upon the warm and cold phases of a climatic cycle with 4.1 ma period highlighted by us since 1998 (Prague), named ?Valach climatic cycle? at that time. This scheme was also based on absolute geological ages of the Neogene important limits: Paleogene-Neogene (23.8 ma), Miocene...

The Khibiny massif is the world?s biggest alkaline pluton with the size of 44 x 35 km in the plan and the area of some 1330 km2. The Devonian intrusion is a conical stock passing into the lopolith. To date, a set of observations and phenomena has been compiled, characterizing the Khibiny massif neotectonics as very complex and contradictory in many respects. It stands out with its high compressive stresses (first tens MPa) of the sub-horizontal position in the area of exploited deposits; major faults traced along ...

The species have been harvested from straw cereals by Barber soil traps.The gathering has been made during the growing season from spring until harvest. In the Barber traps, which consisted of plastic containers height of about 10-12 cm and 8-10 cm in diameter it was placed a solution of about 4% strength formalin. Six traps were used for each experimental variant, with a total of 18 traps. There were done many collection of materials at intervals of 10-12 days, the samples were labeled on each sample specifying: ...

The special resources of renewable energy identified in Romania have generated far more extensive concerns and research on their capture, storage and use. The first part of this paper presents a couple of renewable energy sources, technologies for their capture and conversion, and also several new storage methods and technologies applied worldwide, in order to know the issue, scale and complexity of the field, advantages and difficulties encountered in harnessing these resources. By this we aim to identify the new...

In-Situ Combustion is one of the most important and promising methods for enhancing oil recovery for both light and heavy crude oils from reservoirs. In this method air is injecting into the oil reservoirs and causes ignition and in the next step it effects combustion inside of reservoirs. Nuclear Magnetic Resonance (NMR) spectroscopy as a fast and accessible technique was used to monitoring the light and heavy crude oils oxidation behavior. Herein, we investigated two light and heavy crude oils based on temperatu...

The article presents a comparison of the advantages of natural refrigerants R717 or R744 (with low global warming potential ?GWP and zero ozone depletion potential ? ODP) instead of R404A. Energy Efficiency is also analysed. Romania signed Kyoto and Montreal Protocol and in the same time as a new member of EU has the obligation to respect the environmental legislation as Energy Efficiency Directive, Eco-Design Directive, and Regulation 517/2014 cold ?F-Gas? and to solve Certification System in the field of Air Con...

In this study, investigation of the composition, structure and catalytic activity of the catalyst support based on Ni-Al mixed oxides was carried out. The possibility of controlling structural and acid-base properties of the layered double hydroxides (LDH) by varying the ratio of M2+/M3+ metal cations determines its use as catalyst support. Besides varying of anions in the interlayer space allows to regulate catalytic system activity in the reaction medium. The Ni-Al LDH support was prepared by coprecipitation met...

Vegetation takes the active part in processes of migration and transformation of chemical combinations on the Earth's surface. The intensity of biogenic migration of chemical elements is defined, first of all, by chemical composition of plants. Various security of soils with chemical elements causes also their various accumulation in agricultural plants. Unrationed use of fertilizers, pesticides, broad development of the industry in the territory of the studied region - all these factors allow to classify the Rost...

The main factor of effective biological waste water treatment and pollutants biotransformation is correlation between different nitrogen forms in the media. The waste water specimens were obtained from the pulp and paper mill of the Russian North involving BAS-technology. Concentration of ammonium ions in wastewater was carried out on a spectrophotometer by Sedji-Solorzano method using phenol-hypochlorite reaction. Nitrite ions were determined colorimetrically by diazotization with sulfanilamide and subsequent cou...

The right selections of BHA, (bottom hole assembly), provides to minimize cost of drilling through the elimination of fishing works, which could took place during drilling. In many cases during drilling operations there is need to maintain the continuity of pure drilling works in the wellbore through fishing works. The name of the time for these works, it is known as NPT ? nonproductive time. Before drilling the borehole, the engineers must took into account all geological properties and affordable technological s...

The paper is considering the results of the development of three hundred and three deposits of the Romashkinskoye oilfield, which is composed of porous fractured carbonate reservoirs. The investigation was devoted to the challenges associated with increasing of the production from the carbonate reservoirs on the basis of study concerning the conversion degree of the reserves involved in the development and production through the non-stationary production well operation. The authors present a comparative analysis o...

A number of small mountain ranges (horsts) separated by small basins (grabens) with Tertiary sedimentary filling appeared in the Western Carpathians mostly in their NW and N part. The Tatry Mts. and smaller so called Ru?bachy ?island? are the northernmost horsts from a series of Western Carpathian horsts. Our magnetotelluric measurements focusing particularly on the nature of the Sub-Tatra fault and the interconnection of the Tatry Mts. with the Ru?bachy ?island? confirm steep dip of Sub-Tatra fault in the souther...

The present article reports numerical results of laminar natural convection heat transfer within an air filled semi cylindrical cavity with its horizontal walls submitted to different heating models. In this work, the horizontal surface is maintained at constant temperatures Tc (Dirichlet condition) or heat fluxes q (Newman condition), while that of the opposite surface is considered at cold temperature Tf. The parameters governing the problem are the Rayleigh number (103 < Ra < 106), and the Prandtl number (Pr = ...

The use of bioenergy is gradually increasing, so are the number of different technologies to produce it. Particularly during the last years, new biogas plants had been built across Latvia to ensure more efficient use of farming and other agronomic waste or by-products. The aim of the research is to determine occupational risk factors at biogas plants in Latvia. The research summarises the risk factors of the biogas plant environment, compares the results of observations of biogas plants, performs a survey and an a...

Russian northern territories? cultural advance and development were directly connected to the extraction of minerals. Development of northwest Russia?s mineral resources became more planned and systematic with ?Mining Prikaz? established by Peter the Great. There are numerous old mines preserved in Leningrad region and Karelia, and their cultural potential is underestimated by the state and their historical value is downgraded. This article considers spreading in Russia practices of using shut-down underground min...

The first isolation of the Paratethys from the Tethys Ocean (that included the Mediterranean region), at the beginning of the Oligocene Epoch, at around 33 My (million years) led to significant palaeobiogeographical changes in Europe. The present day Romanian territory belongs, since the Oligocene and up to the Middle Miocene, to the Central Paratethyan domain and afterwards was included in the Eastern Paratethys. The palaeogeographical isolation, produced in the Eastern Carpathians at the Eocene-Oligocene boundar...

Waste from poultry farms represents the greatest danger to people and the environment among all types of bio waste. Approximate estimates show that in Russia up to 15 million tons of manure and a mixture of litter with sawdust or straw are formed annually. The original litter is a toxic substance; the main bacteria in the litter are E. coli and Salmonella. The process of torrefaction of a mixture of manure and sawdust was studied. The torrefaction proceeds in a reactor consisting of three sections with horizontal ...

An exceptional occurrence can generally be regarded as a manifestation of risk. In order to handle it, it is necessary to have sufficient amount of information about the risk itself as well as about potential sources and means to deal with the situation it evokes and the preparedness of citizens. In Slovakia, it is mainly the risks of natural character which are, for the purposes of crisis management, evaluated based on a methodology from the year 1994. The ever-extending list of potential risks leads to the need ...

Strandja Massifs? units form the basement metamorphic units of north western edge parts of Turkey and intruded by the Late Cretaceous felsic and mafic intrusive rocks. The felsic and mafic rocks have a contact metasomatic effects at the border of sedimentary rocks resulting in the formation hornfels, metasandstone and calcsilicaticfels in the composition. Demirk?y is one of the youngest intrusive body which crops out at NE of the massif and mainly composed of granite, granodiorite, diorite and gabbro in compositio...

Soil and its quality are the key factor that determines opportunities for agricultural production in a particular territory. However, through lasting land management practices, soil structure can be significantly modified. In the context of climate change, soils can contribute to increased greenhouse gas emissions; for this reason, the techniques that contribute to sustainable land management have to be used in agricultural production. In many Central European countries, organic soils have been extensively used an...

Woodchip material is one of the most promising fill media for denitrifying bioreactors. Woodchip denitrifying bioreactors are used for nitrate reduction in the outlets of drainage systems, shallow groundwaters, etc. Despite their overall positive effect, undesirable leaching of organic compounds from the fill medium can occur during a bioreactor?s start-up phase. The released organic compounds can cause oxygen depletion and some of them can have a toxic effect on biota. The paper presents the quality of leachates ...

The paper is focused on literature review from the scientific works in area of utilization of biomass in agglomeration process. Actual environmental potential of biomass, as well as its availability, emphasizes the importance of this topic. The composition and properties of biomass differs from the fossil fuels. It is important to view on utilization of biomass in agglomeration process in wired then ecological context. Technological and economical parameters are also important for its utilization. The type pf the ...

The rainwater harvesting systems is a technique which that have been used for many years, with outstanding results that has been used since antiquity. However, it is still not used around the world. Drinking water is an essential element for humanity. However, millions of people do not have access to drinkable water all over the world. Poor countries do not benefit from drinking water even if efforts have been made by governments in developed countries. Poor countries cannot afford modern water treatment and water...

Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. Polar region of the Russia not only play the leading role in world climatic system, but also quickly, with high sensitivity react to climatic changes. Investigation of lake from arctic region has an extreme importance for understanding of the modern environmental processes and their influence on northern ecosystems and biological diversity of these regions. Limnological chara...

Paleosol profiles from the reference section of the Urzhumian stage of Middle Permian in the Cheremushka Ravine, the Kazan Volga region, were studied in order to detail the paleogeographic and palaeoclimatic conditions. Field and laboratory methods, including grain size analysis, optical microscopy, X-ray fluorescence of siliciclastics, X-ray diffraction of clayey component, were used. Urzhumian succession of 70 m thick is represented by red-bed fluvial-lacustrine deposits with predominance of mudstones. The upper...

The results of the palynological analysis of the sediment core recovered in Lake Rubskoe (Ivanovo Region, Russia) in 2015 are presented. An environmental reconstruction of Holocene and late Pleistocene vegetation, climate and lake dynamic was inferred. Pollen analysis has shown that vegetation of the area was dominated by Betula pendula, Pinus and Alnaster. Herbaceous were mostly represented by Artemisia, Chenopodiaceae. Sphagnum spores finding in the in the upper layers of core indicates a significant moisture co...

This paper presents an overview of existing Romanian code provisions for industrial sources or human-induced vibrations. Caused by the industrial sources (forge hammers, presses), vibrations are transmitted to the soil, generating different body and surface waves, and to buildings. On the other hand, vibrations due to sounds are significant on walls and non-structural elements, and even there are not recorded severe damages, with important effects on people. Two studies related on the structural effects and on the...

The paper mentions performance evaluation of thermal solar power plants in conditions of Belgorod region of Russian Federation. The main task is thermal energy production determination of vacuum solar collector in environmental conditions of Belgorod region of Russia. For quantity of heat calculation of thermal solar power plant it is taking into account solar radiation (insolation) changing in different seasons, collector angulation and sun ray angle change in different time, amount of clouds, coefficient of effi...

In the context of climate change and sustainable development, the discussion has been raised in the society about the long-term benefits and possible losses of different farming types. In the discussions about the future of the CAP, it has been stressed that tackling climate change and preserving the environment is the most serious challenge facing the EU, and the CAP must help by setting new goals to ensure that EU farming contributes meeting the international commitments on sustainability. The paper deals with t...

The crystalline basement of the Tatar arch is composed of metamorphic rocks. Locally, areas within its boundaries are composed of magmatic rocks. According to the data of our studies, it is known that within the basement permeable zones are developed, which we attribute to unconventional types of reservoirs. One such object is the hypabyssal rocks, which are alternated by rocks of the gabbro-diabase formation. Based on the results of studying geological-geophysical and core materials of individual areas, in partic...