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Wyniki wyszukiwania dla: soft%20soil
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Volumetric incorporation of NV diamond emitters in nanostructured F2 glass magneto-optical fiber probes
PublikacjaIntegration of optically-active diamond particles with glass fibers is a powerful method of scaling diamond's magnetic sensing functionality. We propose a novel approach for the integration of diamond particles containing nitrogen-vacancy centers directly into the fiber core. The core is fabricated by stacking the preform from 790 soft glass canes, drawn from a single rod dip-coated with submicron diamond particles suspended in...
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Innovative Urban Blue Space Design in a Changing Climate: Transition Models in the Baltic Sea Region
PublikacjaWaterfront areas in cities are subject to constant changes. The desire to integrate the transformed waterside areas with the urban fabric involves shaping high-quality public spaces related to water, which are often referred to as urban blue spaces (UBS). The aim of the research was to examine the transformation processes of urban waterfront areas in the Baltic Sea Region and identify emerging transition models and types of blue...
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Nonlinearity shaping in nanostructured glass-diamond hybrid materials for optical fiber preforms
PublikacjaNanodiamond integration with optical fibers has proved a compelling methodology for magneto-optics. We reveal that the applicability of nanodiamonds in nonlinear optics goes beyond the previous demonstrations of frequency converters. Instead, we exploit the recently reported volumetric integration of nanodiamonds along the optical fiber core and show that the nonlinear response of glasses can be manipulated by nanodiamonds. By...
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Nonlinear dynamic analysis of the pure “buckling” mechanism during blow-out trauma of the human orbit
PublikacjaConsidering the interplay between orbital bones and intraorbital soft tissues, commonly accepted patterns of the blow-out type of trauma within the human orbit require more thorough investigation to assess the minimal health-threatening impact value. Two different three-dimensional finite element method (FEM) models of the human orbital region were developed to simulate the pure “buckling” mechanism of orbital wall fracture in...
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Effect of Chitosan Solution on Low-Cohesive Soil’s Shear Modulus G Determined through Resonant Column and Torsional Shearing Tests
PublikacjaIn this study the effect of using a biopolymer soil stabilizer on soil stiffness characteristics was investigated. Chitosan is a bio-waste material that is obtained by chemical treatment of chitin (a chemical component of fungi or crustaceans’ shells). Using chitosan solution as a soil stabilizer is based on the assumption that the biopolymer forms temporary bonds with soil particles. What is important is that these bonds are biodegradable,...
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Powikłania po rekonstrukcji piersi: problem zakażeń i strategii prewencyjnej - przegląd literaturowy
PublikacjaW niniejszej pracy przedstawiono dane dotyczące powikłań po rekonstrukcji piersi. Manuskrypt ma na celu usystematyzowanie wyników badań z ostatnich lat wraz z aspektami, takimi jak: częstotliwość występowania powikłań oraz ich rodzaj, czynniki predysponujące, a także możliwości profilaktyki. Przeanalizowano dane literaturowe z ogólnie dostępnych artykułów z okresu ostatnich pięciu lat, ze szczególnym uwzględnieniem zakażeń. Do...
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Effectiveness of Random Field Approach in Serviceability Limit State Analysis of Strip Foundation
PublikacjaThis work conducts a probabilistic inquiry on how the variability of the parameter defining soil deformability affects the settlement of the foundation located on the soil. The analysis addresses the random foundation model to relevantly estimate the probability of allowable deflection exceedance. The constitutive model parameter is based either on a single random variable or a random field. The computations incorporate direct...
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Validity of impedance spectra obtained by dynamic electrochemical impedance spectroscopy verified by Kramers-Kronig transformation.
PublikacjaArtykuł przedstawia weryfikację wiarygodności widm impedancyjnych otrzymanych za pomocą niedawno wprowadzonej techniki eksperymentalnej - Dynamicznej Elektrochemicznej Spektroskopii Impedancyjnej (Dynamic Electrochemical Impedance Spectroscopy, DEIS). Technika ta zakłada, że badany system jest pseudostacjonarny jeśli czas pomiaru jest odpowiednio krótki. Czas potrzebny na otrzymanie pojedynczego spektrum zależy od długości okna...
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Detection of random transients caused by pitting corrosion
PublikacjaProces korozyjny może być badany za pomocą techniki szumu elektrochemicznego. Szum obserwowany jest jako fluktuacje prądowe i napięciowe w trójelektrodowym układzie pomiarowym. W celu stwierdzenia obecności korozji wżerowej wykonana została detekcja charakterystycznych sygnałów. Opracowany został algorytm oparty na analizie lokalnych zmian w spektrogramie rejestru prądowego. Spektrogram uzyskany został za pomocą krótkoczasowej...
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Przykłady cyfrowego przetwarzania sygnałów w LabVIEW.
PublikacjaPierwszy rozdział obejmuje podstawy programowania w LabVIEW i zestawienie algorytmów przetwarzania sygnałów dostępnych w tym środowisku. W rozdziale drugim omówiono takie zagadnienia jak próbkowanie, kwantyzacja, aliasing, analiza widmowa, okno czasowe prostokątne i wygładzające. W rozdziale trzecim i czwartym przedstawiono filtry cyfrowe o skończonej i nieskończonej odpowiedzi impulsowej oraz filtrację adaptacyjną. Ostatni rozdział...
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Coatings for improvement of high temperature corrosion resistance of porous alloys
PublikacjaPorowate stopy metaliczne są potencjalnymi podłożami nośnymi dla tlenkowych ogniw paliwo. Ich stosowanie obniża cenę ogniw paliwowych, co zaowocuje ich szybszą komercjalizacą. Jednak są one podatne na korozję w wysokich temperaturach. Dotychczas brak jest metod, które mogą poprawić rezystancję korozyjną porotawych stopów w wysokich temperaturach porowatych stopy do zastosowań SOFC. W tym artykule zaproponowano sposób na poprawę...
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Effects of La Content on the Densification, Microstructure, and Conductivity of Doped La10−x Ge6 O26±δ Electrolytes
PublikacjaIn this study, the influence of La content on the characteristics of Nb-, Mo-, and W-doped LaxGe6O26±δ electrolytes was investigated through sintering study, X-ray diffraction, scanning electron microscopy, and conductivity measurement. The densification of LaxGe5.5Nb0.5O26±δ and LaxGe5.5W0.5O26±δ was retarded as the x reached 9.75, while that of LaxGe5.5Mo0.5O26±δ improved with increasing La content. The average grain size slightly...
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Impact of an unsecured excavation on an underground pipeline
PublikacjaThe paper presents a numerical analysis of the impact of an unsecured excavation on an underground pipeline in selected soil conditions. The research was inspired by a real-life failure of a water pipeline which was caused by a nearby unsecured excavation (Sikora et al. 2015). The failure was triggered by displacement of soil mass in the vicinity of the pipeline. The study conducted in the framework of Finite Element...
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Protocolo de Preparación y Evaluación de Pilas de Combustible de Óxido Sólido
PublikacjaEste protocolo describe la metodología para la preparación de celdas de óxido sólido y su evaluación como pila de combustible (SOFC). Es fruto del estudio realizado en el marco de los proyectos FCTESTNET [1] y SOFCNET [2] del V Programa Marco, en el Comité IEC/TC105 [3] e investigaciones llevadas a cabo en el laboratorio. Las pilas de combustible son dispositivos capaces de transformar la energía química de un combustible en energía...
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Ionic liquids for nano- and microstructures preparation. Part 1: Properties and multifunctional role
PublikacjaIonic liquids (ILs) are a broad group of organic salts of varying structure and properties, used in energy conversion and storage, chemical analysis, separation processes, as well as in the preparation of particles in nano- and microscale. In material engineering, ionic liquids are applied to synthesize mainly metal nanoparticles and 3D semiconductor microparticles. They could generally serve as a structuring agent or as a reaction...
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Comparison of Properties of the Hybrid and Bilayer MWCNTs—Hydroxyapatite Coatings on Ti Alloy
PublikacjaCarbon nanotubes are proposed for reinforcement of the hydroxyapatite coatings to improve their adhesion, resistance to mechanical loads, biocompatibility, bioactivity, corrosion resistance, and antibacterial protection. So far, research has shown that all these properties are highly susceptible to the composition and microstructure of coatings. The present research is aimed at studies of multi-wall carbon nanotubes in three different...
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The Dominant Influence of Plastic Deformation Induced Residual Stress on the Barkhausen Effect Signal in Martensitic Steels
PublikacjaThe paper presents the results of investigation of the influence of plastic deformation on the magnetic properties of martensitic steel (P91 grade). The properties of the hysteresis loops as well as of the Barkhausen effect (BE) signal are analysed for both tensile and compressive loading up to ε = 10% of plastic deformation. The choice of the steel and of the deformation range is unique, since for such combination one can expect...
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Polyurethane Composite Scaffolds Modified with the Mixture of Gelatin and Hydroxyapatite Characterized by Improved Calcium Deposition
PublikacjaThe skeleton is a crucial element of the motion system in the human body, whose main function is to support and protect the soft tissues. Furthermore, the elements of the skeleton act as a storage place for minerals and participate in the production of red blood cells. The bone tissue includes the craniomaxillofacial bones, ribs, and spine. There are abundant reports in the literature indicating that the amount of treatments related...
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A NEW MASTER'S DEGREE PROGRAM IN GEODESY
PublikacjaFaculty of Civil and Environmental Engineering (WILiS) at Gdansk University of Technology (GUT) offers studies in the fields of Geodesy and Cartography. The bachelor program (7 semesters) was started ten years ago in 2009. It provides the student with the basic skills and knowledge in the fields of surveying, geodesy and more generally geomatics and cartography. It is strongly related to expertise knowledge of civil building (geodetic...
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Fe-modified Mn2CuO4 spinel oxides: coatings based on abundant elements for solid oxide cell interconnects
PublikacjaThe current state of the art steel interconnect coating materials are based on critical raw material - Co-oxide spinels. Replacing Co-oxide spinels with alternative, abundant materials can reduce the dependence on the critical raw materials. Cobalt-free coatings with the general formula Mn2-xCuFexO4, where x = 0, 0.1, 0.3, were electrophoretically deposited on a ferritic stainless-steel support and evaluated. Prior to deposition,...
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Multilayer coatings based on cerium oxide and manganese cobaltite spinel for Crofer22APU SOC interconnects
PublikacjaThe current state of the art steel interconnect coating materials are based on critical raw material - Co-oxide spinels. Replacing Co-oxide spinels with alternative, abundant materials can reduce the dependence on the critical raw materials. Cobalt-free coatings with the general formula Mn2-xCuFexO4, where x = 0, 0.1, 0.3, were electrophoretically deposited on a ferritic stainless-steel support and evaluated. Prior to deposition,...
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Design of a Shape-Memory-Alloy-Based Carangiform Robotic Fishtail with Improved Forward Thrust
PublikacjaShape memory alloys (SMAs) have become the most common choice for the development of mini- and micro-type soft bio-inspired robots due to their high power-to-weight ratio, ability to be installed and operated in limited space, silent and vibration-free operation, biocompatibility, and corrosion resistance properties. Moreover, SMA spring-type actuators are used for developing different continuum robots, exhibiting high degrees...
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An Overview of Sport and the Future Smart Cities
PublikacjaOne of the main challenges for future cities is to strengthen the role of people and their activities. Therefore, sport provides an opportunity to engage in physical activity, connecting citizens to the city. The question of how sport influences the development of cities and the concept of future smart cities arises. The aim of this study is to examine the relationship between sport and the concept of smart cities by identifying...
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Halucynacje chatbotów a prawda: główne nurty debaty i ich interpretacje
PublikacjaGeneratywne systemy sztucznej inteligencji (SI) są w stanie tworzyć treści medialne poprzez zastosowanie uczenia maszynowego do dużych ilości danych szkoleniowych. Te nowe dane mogą obejmować tekst (np. Bard firmy Google, LLaMa firmy Meta lub ChatGPT firmy OpenAI) oraz elementy wizualne (np. Stable Diffusion lub DALL-E OpenAI) i dźwięk (np. VALL-E firmy Micro- soft). Stopień zaawansowania tych treści może czynić je nieodróżnialnymi...
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Effect of the Drying Method of Pine and Beech Wood on Fracture Toughness and Shear Yield Stress
PublikacjaThe modern wood converting processes consists of several stages and material drying belongs to the most influencing future performances of products. The procedure of drying wood is usually realized between subsequent sawing operations, affecting significantly cutting conditions and general properties of material. An alternative methodology for determination of mechanical properties (fracture toughness and shear yield stress) based...
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Probabilistic analysis of settlements under a pile foundation of a road bridge pylon
PublikacjaThe paper addresses the reliability change of a road bridge pile foundation due to the unpredictable increase of settlements in time. The analysis is based on the Rędziński Bridge in Wrocław, Poland, its design assumptions, and monitoring results. The bridge foundation rests on a multi-layered subsoil assumed random. The Finite Element model of the subgrade is generated in ZSoil® software. To simplify the probabilistic approach,...
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Tuning Electrochemical Performance by Microstructural Optimization of the Nanocrystalline Functional Oxygen Electrode Layer for Solid Oxide Cells
PublikacjaFurther development of solid oxide fuel cell (SOFC) oxygen electrodes can be achieved through improvements in oxygen electrode design by microstructure miniaturisation alongside nanomaterials implementation. In this work, improved electrochemical performance of an La0.6Sr0.4Co0.2Fe0.8O3-d (LSCF) cathode was achieved by the controlled modification of the La0.6Sr0.4CoO3-d (LSC) nanocrystalline interlayer introduced between a porous...
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Metody modyfikacji katod w tlenkowych ogniwach paliwowych
PublikacjaW pracy przedstawiono podstawowe zasady działania ogniw tlenkowych SOFC i kilka najważniejszych metod modyfikacji występujących w nich katod. Opisanymi metodami są: tworzenie warstwy kolektora prądowego, zmniejszenie wielkości ziarna, tworzenie warstwy kompozytowej, infiltracja katody cząstkami innej fazy i tworzenie warstw z gradientem składu fazowego. Metody te umożliwiają: polepszenie szybkości reakcji redukcji tlenu, własności...
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Chirp Rate and Instantaneous Frequency Estimation: Application to Recursive Vertical Synchrosqueezing
PublikacjaThis letter introduces new chirp rate and instantaneous frequency estimators designed for frequency-modulated signals. These estimators are first investigated from a deterministic point of view, then compared together in terms of statistical efficiency. They are also used to design new recursive versions of the vertically synchrosqueezed short-time Fourier transform, using a previously published method (D. Fourer, F. Auger, and...
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MOŻLIWOŚCI IDENTYFIKACJI STANU TECHNICZNEGO WARSTW ŚLIZGOWYCH ŁOżYSK SILNIKÓW SPALINOWYCH O ZAPŁONIE SAMOCZYNNYM W PRZYPADKU WYKORZYSTANIA EMISji AKUSTYCZNEJ JAKO SYGNAŁU DIAGNOSTYCZNEGO
PublikacjaW artykule zaprezentowano wyniki badań wielowarstwowych panwi łożysk ślizgowych silników tłokowych. Scharakteryzowano własności obciążeń tego rodzaju panwi oraz ich zużycia szczególnie zmęczeniowego i ściernego. Wykazano przydatność emisji akustycznej jako sygnału diagnostycznego do ujawniania zużycia powłok ślizgowych i zaporowych. Przedstawiono wyniki pomiarów parametrów emisji akustycznej, wykonanych za pomocą 12- kanałowej...
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Numerical solutions for large deformation problems in geotechnical engineering
PublikacjaThe problem of large deformations often occurs in geotechnical engineering. Numerical modeling of such issues is usually complex and tricky. The chosen solution has to implicate soil-soil and soil-structure interactions. In this paper, a review of the most popular numerical methods for large deformation problems is presented. The Coupled Eulerian-Lagrangian (CEL) method, the Arbitrary Lagrangian-Eulerian (ALE) method, the Smoothed...
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Excavation induced cast iron pipeline failure – a numerical study
PublikacjaNumerical study on impact of an unsecured excavation on an underground pipeline. Analysis focused on investigation of pipeline displacement generated by soil movement caused by excavation and heavy traffic. Numerical calculations and soil parameter sensitivity analysis based on Finite Element Method. Some comparisons of results with real-life failure cases.
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Carbon nanowalls: A new versatile graphene based interface for laser desorption/ionization-mass spectrometry detection of small compounds in real samples.
PublikacjaCarbon nanowalls, vertically aligned graphene nanosheets, attract attention owing to their tunable band-gap, high conductivity, high mechanical robustness, high optical absorbance and other remarkable properties. In this paper, we report for the first time, the use of hydrophobic boron-doped carbon nanowalls (CNWs) for laser desorption/ionization of small compounds and their subsequent detection by mass spectrometry (LDI-MS). The...
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Behaviour of deformed steel columns exposed to impact load during earthquakes: numerical analysis
PublikacjaIt has been observed during earthquakes that the so called soft-storey failure of an upper floor of a building leads to considerable vertical impact load acting on structural members of the lower storeys. The aim of this paper is to investigate numerically the behaviour of horizontally deformed columns (deformation as the result of earthquake loading) that are additionally subjected to vertical impact load. In the first stage of...
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Podatność na degradację poliuretanów z syntetycznym polihydroksymaślanem w środowisku utleniającym i hydrolitycznym
PublikacjaPoliuretany (PURs), zawierające w segmencie giętkim ataktyczny, telecheliczny poli([R,S]-3-hydroksymaślan) (a-PHB) oraz polikaprolaktonodiol (PCL) lub polioksytetrametylenodiol (PTMG), poddano degradacji hydrolitycznej i oksydacyjnej. Poliuretany poddano degradacji hydrolitycznej w buforze fosforanowym z dodatkiem NaN3 w czasie 36 tygodni oraz oksydacyjnej w roztworze CoCl2/H2O2 w czasie 16 tygodni inkubacji. Próbki inkubowano...
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Tyre/road noise reduction by a poroelastic road surface
PublikacjaLow noise road surfaces of existing types may in favourable cases and in new conditions provide up to 7 dB of noise reduction. For higher noise reductions, innovative solutions must be sought. Poroelastic road surfaces (PERS) may be such a solution, which currently is studied in the EU project PERSUADE. This paper presents results of trials with a PERS version prefabricated by one of the project partners. Tests were made in a laboratory...
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Factors determining accumulation of bisphenol A and alkylphenols at a low trophic level as exemplified by mussels Mytilus trossulus
PublikacjaThe aim of the study was to investigate abiotic and biotic factors influencing the accumulation of endocrine disrupting compounds (EDCs) such as bisphenol A (BPA), 4-tert-octylphenol (OP) and 4- nonylphenol (NP) in mussels Mytilus trossulus from the Gulf of Gdansk (Southern Baltic). The key abiotic factor influencing BPA, OP and NP accumulation in mussels is their hydrophilicity/lipophilicity, which affects their main assimilation...
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Multi-Technique Investigation of Grave Robes from 17th and 18th Century Crypts Using Combined Spectroscopic, Spectrometric Techniques, and New-Generation Sequencing
PublikacjaThe textile fragments of the funeral clothes found in the 17th and 18th century crypts were subjected to spectroscopic, spectrometric, and microbial investigation. The next-generation sequencing enabled DNA identification of microorganisms at the genus and in five cases to the species level. The soft hydrofluoric acid extraction method was optimized to isolate different classes of dyes from samples that had direct contact with...
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A comprehensive review on current and emerging technologies toward the valorization of bio‐based wastes and by products from foods
PublikacjaIndustries in the agro-food sector are the largest generators of waste in the world. Agro-food wastes and by products originate from the natural process of senescence, pretreatment, handling, and manufacturing processes of food and beverage products. Notably, most of the wastes are produced with the transformation of raw materials (such as fruits, vegetables, plants, tubers, cereals, and dairy products) into different processed...
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Boron-doped carbon nanowalls for fast and direct detection of cytochrome C and ricin by matrix-free laser desorption/ionization mass spectrometry
PublikacjaDetecting proteins via surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) method is still highly challenging, and only few examples of nanomaterials have been demonstrated to perform such detection so far. In this study, carbon nanowalls (CNWs), vertically aligned graphene sheet-based materials, presenting specific morphology, dimensions, and boron doping levels have shown improved performances for both qualitative...
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Impact evaluation of a cycling promotion campaign using daily bicycle counters data: The case of Cycling May in Poland
PublikacjaThe promotion of active and sustainable transport modes as an alternative to motorised individual transport has become a key policy priority in Europe, to reduce air pollution, road congestion, noise, traffic injuries, and the adverse health outcomes of sedentary lifestyles. Policymakers are implementing a wide range of measures to encourage this shift in attitudes and behaviours. These interventions are most valuable when targeting...
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Insights into Stoichiometry Adjustments Governing the Performance of Flexible Foamed Polyurethane/Ground Tire Rubber Composites
PublikacjaPolyurethanes (PU) are widely applied in the industry due to their tunable performance adjusted by changes in the isocyanate index—stoichiometric balance between isocyanate and hydroxyl groups. This balance is affected by the incorporation of modifiers of fillers into the PU matrix and is especially crucial for PU foams due to the additional role of isocyanates—foaming of the material. Despite the awareness of the issue underlined...
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Advanced fatigue and rutting characterisation of Polish asphalt mixtures based on the VECD model and viscoplastic shift model
PublikacjaThe advanced asphalt mixture performance-related specifications (AM-PRS) recently developed in USA can allow an optimisation of the design process of asphalt pavements thanks to the possibility to fully take into account the intrinsic material properties. In this study, four typical Polish mixtures, i.e. a Stone Mastic Asphalt (SMA) for wearing course, two mixtures for binder course with neat bitumen or Polymer modified Bitumen...
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Przyczółki mostowe z konstrukcją odciążającą z gruntu zbrojonego geosyntetykami
PublikacjaPrzegląd najważniejszych cech geotekstyliów i wyrobów pokrewnych, zastosowanych do budowy bloków odciążających ze szczególnym uwzględnieniem ich wytrzymałości długo i krótkookresowej oraz reologii. Określenie obciążeń działających na konstrukcję gruntową współpracującą z przyczółkiem; obciążenia normowe i rzeczywiste. Obliczenia konstrukcji z gruntu zbrojonego współpracującej z przyczółkiem
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Polymer journal bearings behaviour research under limited lubrication and cooling conditions conducted on high torque test rig
PublikacjaPolymer journal bearings are frequently used as a water-lubricated bearings of small marine units’ propeller shafts . Choice of these bearings is based on their simple construction and relatively low purchase and maintenance costs. Although properly designed and installed water lubricated bearings may well last for over a decade, rapid wear or failure of these bearings can be observed...
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The impact of footing conditions of a vertical-axis floating-roof tank on structural shell deformation
PublikacjaStructural shells of fuel tanks are often subjected to geometric imperfections which may lead to exceeding the ultimate and serviceability limit states. One of the means triggering shell deformation is non-uniform settlement caused by incoherent soil conditions. Analysis carried out in the work concerns of vertical-axis, floating-roof cylindrical shell which volume is 50.000 m3, founded on a complex multi-layered soil. The sensitivity...
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The mechanism of grouting action under the base of bored pile
PublikacjaThe grouting under the base of bored pile is carried out in order to reduce pile settlement and improve its bearing capacity. The principal aim of grouting is to introduce an initial force between the soil and the pile base. In non-cohesive soil, the grouting can also enlarge the pile base area and therefore improve the base resistance. The example of static load tests on instrumented bored piles installed with and without grouting...
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Use of Brassica plants in the phytoremediation and biofumigation processes
PublikacjaIn recent decades, serious contamination of soils by heavy metals has been reported. It is therefore a matter of urgency to develop a new and efficient technology for removing contaminants from soil. Another aspect to this problem is that environmental pollution decreases the biological quality of soil, which is why pesticides and fertilizers are being used in ever-larger quantities. The environmentally friendly solutions to these...
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Phytoremediation of heavy metals by white cabbage
PublikacjaPhytoremediation is regarded as the cheapest and environmentally most friendly technology for cleaning up soil. The most widespread and most profitable technique is phytoextraction, used mainly for removing heavy metals and radioactive elements from thesoil. Over 400 plant species have been identified as natural metal hyperaccumulators representing about 0.2 % of all angiosperms. Unfortunately, most of these plants are characterised...
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Random field model of foundations at the example of continuous footing
PublikacjaThe purpose of the paper is to indicate an efficient method of foundation settlement analysis taking into account the variability of soil properties. The impact of the random variable distribution (Gauss or Lognormal) describing soil stiffness on foundation deposits was assessed. The Monte Carlo simulation method was applied in the computations. The settlements of the strip foundation with the subsoil described by a single random...