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Reservoir Influence on Pressure Wave Propagation in Steel Pipes
PublicationThe relation between the length of steel pipe and the pressure wave period in the system, reservoir-pipe-valve, is discussed. Experiments carried out for the short steel pipes showed that in such a system, the pressure wave celerity estimated using the measured wave cycles systematically increases with the increase of the pipe length. The observed differences can exceed even 90 m=s. As the pressure wave traveling in the pipe with...
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Temperature influence on tyre/road noise frequency spectra
PublicationThe correction for temperature effect on measured tyre/road noise is very important as it may be one of the main sources of errors in measurement results due to substantial influence of this parameter on obtained values. The latest version of the Technical Specification ISO/CD TS 13471-1 about Temperature Corrections contains a proposal of correction procedure for normalizing measured noise levels to a reference air temperature...
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Influence of Sb-substitution on ionic transport in lanthanum orthoniobates
PublicationThe results of ionic transport measurements for the lanthanum orthoniobate substituted with 10 and 30 mol% of antimony (LaNb0.9Sb0.1O4 and LaNb0.7Sb0.3O4) are presented and discussed. The influence of calcium co-doping on these properties has also been analysed. It has been shown that for the investigated material protonic conductivity predominates at temperatures up to 800 °C in oxidizing atmospheres under wet conditions. The...
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The Influence of Articular Cartilage Thickness Reduction on Meniscus Biomechanics
PublicationObjective Evaluation of the biomechanical interaction between meniscus and cartilage in medial compartment knee osteoarthritis. Methods The finite element method was used to simulate knee joint contact mechanics. Three knee models were created on the basis of knee geometry from the Open Knee project. We reduced the thickness of medial cartilages in the intact knee model by approximately 50% to obtain a medial knee osteoarthritis...
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Influence of selected additives and admixtures on underwater concrete and the environment
PublicationThe intensive civilization development has an influence on searching for new possibilities connected with extension of city agglomerations, both the areas of flat building and the industrial areas. One of the most interesting solution is to use water reservoirs, rivers and sea areas. The extension of buildings has an influence on building materials, especially hydrotechnical, which means development of production of hydrotechnical...
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The influence of historical conditions on time and cost of construction project
PublicationConducting construction works in a building or in an area entered in the historic register is associated with the contracting authority's risk of incurring higher than planned costs of works, as well as delays in their implementation. In many cases, these deviations are completely independent of contracting authority and contractor. The aim of this article is to indicate the reasons for cost and time changes in the construction...
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The influence oil additives on spread cracks in silicon nitride
PublicationThe paper presents an experimental study of the influence of oil additives (Cl, S, P, cerium dioxide (CeO2)) on spread cracks in silicon nitride. The additives Cl, S, P are bound in molecules in liquid form soluble in the base oil. The CeO2 is purely in powder form in suspension. The use of CeO2 powder was made based on the good results of polishing of silicon nitride. A ceramic angular contact ball bearing was modelled using a...
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The influence of dimensional accuracy on steel structures cost calculation
PublicationW referacie przedstawiono zależność pomiędzy wartością tolerancji a kosztami wytwarzania budowlanych konstrukcji stalowych. Opisano zasady klasyfikacji tolerancji prętowych konstrukcji stalowych z uwagi na porawny montaż konstrukcji wyrażony równaiem pętli montażowej. Przedstawiono podstawy analizy i syntezy tolerancji oraz zaproponowano nową formułę optymalizacji kosztów wytwarzania. Wskazano metody rozwiązania zadania optymalizacyjnego.
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Evaluation of the influence of grapevine growing conditions on wine quality
PublicationScientists are increasingly interested in the viticulture concept of terroir, which states that unique properties of wine are strictly related to the environmental conditions under which grapes are cultivated. The aim of the research was to compare the parameters characterizing wines produced in Poland, such as pH, conductivity, total organic carbon (TOC), and concentration of anions (F−, Cl−, NO2−, NO3−, PO43−, SO42−). It was...
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INFLUENCE OF INLET GEOMETRY ON THE EFFICIENCY OF 1MW STEAM TURBINE
PublicationThe process of the design of the 1MW steam turbine includes designing the stator and rotor blades, the steam turbine inlet and exit, the casing and the rotor. A turbine that operates at rotation speeds other than 3000 rpm requires a gear box and generator with complex electronic software. This paper analyses the efficiency of eight turbine variants, including seven inlet geometries and three stages of stator as well as an eight...
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The Influence of Laser Alloying of Ti13Nb13Zr on Surface Topography and Properties
PublicationThe laser alloying is a continually developing surface treatment because of its significant and specific structuration of a surface. In particular, it is applied for Ti alloys, being now the most essential biomaterials` group for load-bearing implants. The present research was performed on the Ti13Nb13Zr alloy subject to laser modification in order to determine the treatment effects on surface topography and its some mechanical...
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Influence of Processing Conditions on Crystal Structure of Bi6Fe2Ti3O18 Ceramics
PublicationAim of the present research was to apply a solid state reaction route to fabricate Aurivillius-type ceramics described with the formula Bi6Fe2Ti3O18 (BFTO) and reveal the influence of processing conditions on its crystal structure. Pressureless sintering in ambient air was employed and the sintering temperatures were 850 and 1080 °C. It was found that the fabricated BFTO ceramics were multiphase ones. They consisted of two Bim+1Fem-3Ti3O3m+3...
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Influence of the thermal modernization of window on transmission heat losses
PublicationThe article presents the results of calculations of the heat transfer coefficient for the state before and after renovation for the historic windows. The aim of the analysis was to obtain the values of thermal insulation parameters demanded by the regulations, while not losing the historical value of the window. The described example of the renovation of the existing window consisted in installing an additional window panel from...
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Influence of operation temperature instability on gas sensor performance
PublicationGas sensors based on the semiconducting metal-oxides, such as SnO2, have been found to be very useful for detecting a wide range of gases. The reversible interactions of the gas with the surface of the sensing layer made of semiconducting metal-oxides are responsible for changes of sensor resistance which is usually used as a measure of sensor response. Semiconductor gas sensors are commercially available and applied in numerous...
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Influence of lubricating oil improvers on performance of crankshaft seals
PublicationThis paper presents an original method for checking influence of lubricating oil improvers on performance of crankshaft seals of combustion piston engine. Crankshaft seals were tested with the use of a modified friction node of T-02 four- ball apparatus in laboratory conditions. The tests were conducted according to a worked-out algorithm. Their results confirmed usefulness of the method for determining „harmful” performance...
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The Influence of LED Lighting Sources on the Nature of Power Factor
PublicationThis article presents measurements of electric power absorbed by a newly built facility for office and scientific research activities. These measurements highlighted the need for compensation of capacitive reactive power—not predicted by the designer—due to the vast use of LED lighting in the facility. The article also describes a reactive power compensation system, designed on the basis of the above-mentioned measurements, and...
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Raw material influence on volatile composition of agricultural distillates
PublicationCelem prezentowanej pracy było określenie za pomocą techniki HS-SPME/GC-MS charakterystycznych związków markerowych pozwalających na identyfikację pochodzenia surowcowego destylatów rolniczych. Przeprowadzone badania wskazały kilkanaście związków na podstawie obecności których można określić surowiec jakiego użyto przy produkcji destylatu.
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The influence of disinfection by-products on swimmers and swimming pool staff
PublicationW większości przypadków na basenach kąpielowych stosuje się chlorowanie jako metodę dezynfekcji wody. Produkty uboczne dezynfekcji, a także ich negatywny wpływ na zdrowie człowieka jest dobrze znany. Dezynfekcja wody prowadzi do tworzenia się produktów ubocznych. W pracy omówiono negatywny wpływ owych produktów zarówno na kąpiących się jaki i personel przebywający w hali basenowej
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The influence of glycols on thermal stability and chemical structure of glycolysates
PublicationW pracy omówiono wpływ glikoli (etano-1,2-diolu - heksano-1,6-diolu) na właściwości termiczne oraz budowę chemiczną glikolizatów. Analizy przeprowadzono dla półproduktów wytworzonych w jednym stosunku masowym odpadowego poliuretanu do glikolu wynoszącego 10:1.
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Modelling of vertical wall influence on the single bubble motion.
PublicationW referacie zaprezentowano rezultaty badań eksperymentalnych i modelowania matematycznego siły odpychającej, działającej na model pęcherzyka przepływający wzdłuż ściany pionowej. Zaobserwowano okresowy charakter tej siły oraz stwierdzono, że zależy ona od liczby Reynoldsa. Porównanie obliczonych i zmierzonych wartości siły wykazało satysfakcjonującą zgodność.
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Influence of test procedure on surge impedance of lightning earthings.
PublicationUziemienia systemu ochrony odgromowej powinny być badane prądami o parametrach czasowych podobnych do rejestrowanych podczas wyładowań atmosferycznych.Podano definicję impedancji i warunki jej pomiaru. omówiono pojęcie długości efektywnej uziomu.
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Modelling of Vertical Wall Influence on the Single Bubble Motion
PublicationW referacie pokazano rezultaty badań eksperymentalnych i modelowania matematycznego siły odpychającej, działającej na model pęcherzyka przepływający wzdłuż ściany pionowej. Zaobserwowano okresowy charakter siły oraz stwierdzono, że zależy ona od liczby Reynoldsa. Porównanie obliczonych i zmierzonych wartości siły wykazało satysfakcjonującą zgodność.
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Influence of the grain boundaries on conductivity of yttrium stabilized zirconia
PublicationW pracy przedstawiono wyniki badań przewodności domieszkowanego tlenku cyrkonu. Przygotowano tlenk cyrkonu o krystalitach od 100nm to 10um. Badania impedancyjne pozwoliły na określenie przedności ziaren oraz obszarów międzyziarnowych.
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Cavitacion erosion, influence of electrochemical corrosion on cavitation - a review
PublicationZjawisko kawitacji polega na narastaniu, a następnie zapadaniu się i implozji pęcherzy wypełnionych gazem lub parami. Zachodzi ono niemalże we wszystkich układach hydrodynamicznych np. w pompach, zaworach, na śrubach okrętowych, turbinach, hydropłatach itp. na skutek lokalnej, gwałtownej zmiany ciśnienia. W większości przypadków jest to zjawisko niepożądane, ponieważ siły generowane podczas implozji pęcherzy kawitacyjnych są tak...
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Influence of Humidity on Parameters of Amperometric Sensor with Nafion Membrane
PublicationPrzedstawiono wyniki badań wpływu umiarkowanych i wysokich wilgotności powietrza na sygnał, czułość i czas odpowiedzi prototypowego czujnika ditlenku siarki ze złotą elektrodą pracującą, próżniowo napyloną na powierzchnię membrany nafionowej. Zaprezentowano także wyniki badań impedancyjnych w zakresie potencjałów, w którym mechanizm utleniania ditlenku siarki jest kontrolowany aktywacyjnie i dyfuzyjnie. Parametry odpowiadające...
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The influence of preparing conditions on the properties of SrTi0.98Nb0.02O3-YSZ composite
PublicationZbadano wpływ warunków przygotowania na właściwości kompozytów SrTi0.98Nb0.02O3-YSZ jako potencjalnych warstw przejściowych między anodą a elektrolitem w tlenkowych ogniwach paliwowych SOFC. Udowodniono, że proces wstępnej obróbki temperaturowej substratów oraz sposób ich mielenia znacznie wpływa na przewodnictwo elektryczne badanych materiałów.
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The influence of pressure drop on the working volume of a hydraulic motor
PublicationReliability and maintenance analysis of hydraulic positive machines basicly focused on the processes of their wear and failure. But in order to correctly assess the mechanical and volumetric efficiency of a hydraulic motor, both at the stage of development research or at the stage of control tests during its exploitation, the working volume of this motor must be correctly determined. Therefore this paper proposes a new method of...
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Tyre rolling resistance and its influence on fuel consumption
PublicationRolling resistance of tyres is one of the major resistive forces acting on any wheeled vehicle. Unfortunately, it is also one of the forces very difficult to measure. It is estimated that in certain traffic conditions (like for example constant speed driving with slow or moderate speed) so called Rolling Resistance Impact Factor may be as high as 0.3. This means that reduction of rolling resistance by 50% would lead to 15% of energy...
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Temperature influence on tyre/road noise of selected tyres
PublicationAir and road temperatures substantially affect road vehicle noise emission. The temperature influence on tyre/road noise depends mainly on tyre-road combination. It is different for dense and porous pavements, for bituminous and cement ones. It differs also depending on tyres. The correction procedures for temperature effect are still under consideration and preparation. Tyre/road noise measurements using CPX method were performed...
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Influence of meteorogical conditions om PM10 concentration in Gdańsk
PublicationThe paper presents the investigation of influence of meteorological conditions on the concentration of PM!) in Gdańsk in 2011 year. on the examples of episodes og high concentrations in this year. The results have shown the most crucial factors for high episodes of PM10: anticyclone atmospheric circulation, stable atmosphere conditions, low wind velocity and the occurence of inversion layer.
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VARIABLE KINEMATICS OF HONING PROCESS – INFLUENCE ON MACHINED WORKPIECE
PublicationSurface quality of holes plays an important role in machine manufacturing industry especially in the production of car engines and hydraulic cylinders. Investigations of honing process were carried out by 6 years on horizontal CNC Sunnen’s honing machine HTH 4000S, on vertical conventional honing machine WMW’s SZS 200 and on CNC milling machine of Haas VF 3SS with equipment of Honingtec for honing. Measurements of cylindricity...
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The Influence of External Load on the Performance of Microbial Fuel Cells
PublicationIn this work, the effect of the external load on the current and power generation, as well as on the pollutant removal by microbial fuel cells (MFCs), has been studied by step-wise modifying the external load. The load changes included a direct scan, in which the external resistance was increased from 120 Ω to 3300 Ω, and a subsequent reverse scan, in which the external resistance was decreased back to 120 Ω. The reduction in the...
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The influence of robotization on the reliability of the production process in the bakery industry
PublicationThis article presents a new concept of technological system reliability based on the analysis of the relationship of associations of elements of energy streams, matter, information, time and finance. The method of stream specification and the method of determining the reliability values of significant and supporting relationships are given. Relevant relationships between elements of system streams were defined as having one-time...
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The Influence of the Cuboid Float’s Parameters on the Stability of a Floating Building
PublicationUsually, the concept of sufficient stability of a floating structure is connected with the capacity to keep a small heel angle despite the moment of heeling. The variable responsible for these characteristics is the initial metacentric height, which is the relation between the hydrostatic features of the pontoon and the mass properties of the entire object. This article answers the questions of how heavy the floating system should...
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Influence of Urea and Dimethyl Sulfoxide on K-Peptide Fibrillation
PublicationProtein fibrillation leads to formation of amyloids—linear aggregates that are hallmarks of many serious diseases, including Alzheimer’s and Parkinson’s diseases. In this work, we investigate the fibrillation of a short peptide (K-peptide) from the amyloidogenic core of hen egg white lysozyme in the presence of dimethyl sulfoxide or urea. During the studies, a variety of spectroscopic methods were used: fluorescence spectroscopy...
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Influence of preprocessing techniques on pulse pressure velocity determination
PublicationPulse Wave Velocity (PWV) is measured and utilized in many clinical applications. Recently, a wide research has been led to develop a cuff-less and continuous blood pressure method basing on PWV. However, in this application a decision on choosing an appropriate fiducial point of pulse wave (PW) waveform is necessary and substantial. It would allow to measure time parameters necessary to determine PWV. An influence of sampling...
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Influence of Holes Manufacture Technology on Perforated Plate Aerodynamics
PublicationTranspiration flow is a very important and still open subject in many technical applications. Perforated walls are useful for the purpose of “flow control”, as well as for the cooling of walls and blades (effusive cooling) in gas turbines. We are still not able to include large numbers of holes in the numerical calculations and therefore we need physical models. Problems are related also to the quality of the holes in perforated...
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TEMPERATURE INFLUENCE ON TIRE ROLLING RESISTANCE MEASUREMENTS QUALITY
PublicationGlobal warming makes it necessary to reduce energy consumption, which in the case of motor vehicles, is connected, among other things, with reduction of resistive forces acting on a vehicle during its motion. One of the most important components of those forces is rolling resistance, which is very difficult to measure, especially in road conditions. The article deals with issues related to the influence of the thermal state of...
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INFLUENCE OF CERAMIC COATING ON MECHANICAL PROPERTIES OF STAINLESS STEEL
PublicationCrystal structure and phase composition of stainless steel substrates (AISI 304 type) was studied and it was found that they adopted the cubic symmetry. The calculated elementary cell parameter for the mayor Fe-Ni phase (weight fraction 99%) was a = 3.593 Å, whereas the mean grain size was = 2932 Å. Morphology of the stainless steel substrate surface was studied with profilometry. Mechanical properties of the stainless steel...
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Influence of the grains shape on the mechanical behavior of granular materials
PublicationDiscrete Element Method is a numerical method suitable for modeling geotechnical problems concerning granular media. In most cases simple forms of grains, like discs or spheres, are used. But these shapes are capable of soil behavior modeling up to a certain point only, they cannot reflect all of the features of the medium (large shear resistance and large volumetric change). In order to reflect the complex behavior of the real...
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Influence of grain shape on the mechanical behaviour of granular materials
PublicationWe performed series of numerical vertical compression tests on assemblies of 2D granular material using a Discrete Element code and studied the results in regard to the grain shape. The samples consist of 5000 grains made either of 3 overlapping discs (clump - grain with concavities) or of six-edged polygons (convex grain). These two types of grains have a similar external envelope, ruled with a geometrical parameter α. In the...
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The influence of road surface unevenness on tyre rolling resistance
PublicationThe geometric characteristics of road surface substantially affect the interaction between tyre and road. Depending on pavement texture wavelength, the texture chiefly affects tyre/road friction, rolling resistance, interior and exterior noise, tyre wear, and ride comfort. The article presents results of investigations on the influence of road surface unevenness on the rolling resistance of passenger car and truck tyres. The tests...
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INFLUENCE OF LOAD AND INFLATION PRESSURE ON THE TYRE ROLLING RESISTANCE
PublicationTyre load and inflation pressure are important factors controlling rolling resistance of road vehicles. The article presents results obtained in the Technical University of Gdańsk during laboratory and road measurements of different car tyres rolling on different pavements. The knowledge of rolling resistance characteristics is important for modelling car dynamics as well as fuel consumption. It is also necessary to establish proper...
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Influence of control loop on torsional vibrations of rotating machinery.
PublicationRozpatrywano wpływ pętli regulacyjnej silnika diesla na dynamikę układu napędowego okrętowego. Porównano obliczenia numeryczne z badaniami eksperymentalnymi. Stwierdzono duży wpływ pętli regulacyjnej silnika diesla na dynamikę układu. W obliczeniach numerycznych skoncentrowano się na drganiach skrętnych układu napędowego okrętowego. Analizowano wpływ sztywności skrętnej sprzęgła elastycznego na amplitudy momentów skrętnych...
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Influence on micrograins size on the distance between the workpiece and the lap.
PublicationNa kształtowanie powierzchni docieranej główny wpływ ma błąd kształtu zastosowanego narzędzia. Intensywność docierania zależy od wielkości zastosowanych ziaren ściernych, które również wpływają na błędy kształtu przedmiotu. W referacie przedstawiono wyniki obliczeń odległości przedmiotu od powierzchni narzędzia w funkcji wielkości ziaren ściernych.
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The influence of the filler on the magnetic field distribution in ferromagnetic objects.
PublicationDuże obiekty ferromagnetyczne umieszczone w zewnętrznym polu magnetycznym (np. ziemskim polu magnetycznym) ulegają namagnesowaniu. W pewnych przypadkach konieczna jest demagnetyzacja obiektu ferromagnetycznego. Demagnetyzacja polega na umieszczeniu obiektu w wytworzonym w układzie zewnętrznym polu magnetycznym o określonych właściwościach. Jeżeli obiekt ferromagnetyczny posiada duże rozmiary, wówczas jego demagnetyzacja jest problemem...
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Influence of bulk solids on the buckling strength of silo shells.
PublicationW artykule przedstawiono wyniki numerycznej nieliniowej analizy wyboczenia powłok silosowych pustych i wypełnionych materiałem sypkim. Obliczenia wykonano dla różnych imperfekcji w powłoce. Wyniki teoretyczne porównano z wynikami doświadczalnymi wykonanymi w Uniwersytecie Karlsruhe.
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Geotechnical Aspects of Dike Construction Using Soil-Ash Composites
PublicationAn analysis of using of anthropogenic materials, mainly ashes from Coal Combustion Products (CCP), for dike construction is shown. Perspectives of anthropogenic materials application in geotechnical engineering and their advantages in sense of the carbon dioxide reduction are discussed. According to regulations of Kioto Protocol 2005 and EU agreement “Energy Roadmap 2050” recycled materials have higher usage priority than natural...
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Manganese dioxide (MnO2) nanoparticles influence on the nitrification and anammox activity
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Influence of whole body cryotherapy on depressive symptoms – preliminary report
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