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The methods of fretting wear prevention in machine elements : chapter 9
PublicationOpisano skutki procesu frettingu w elementach maszyn i warunki ich wystąpienia. Przedstawiono przegląd metod zapobiegania zużyciu frettingowemu i jego ograniczania. Opisano laboratoryjne badania zużywania frettingowego wybranych skojarzeń w warunkach umożliwiających ograniczanie zużycia.
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Damage detection in elements of strutures by the elastic wave propagation method.
PublicationW pracy przedstawiono wyniki badań dotyczace wykorzystania fal sprężystych do detekcji uszkodzeń i jedno i dwu wymiarowych elementach konstrukcyjnych.
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Mesoscopic simulations of crack propagation in concrete using cohesive elements
PublicationThe paper presents results of two-and three-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 3-phase material composed of aggregate grains placed in the cement matrix with Interfacial Transitional Zones (ITZs) between then. In 2D simulations macro-voids were also taken into account. The particle distribution was taken from real concrete beams...
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Accuracy improvement of the prestressed concrete structures precise geometry assessment by use of bubble micro-sampling algorithm
PublicationPrestressed concrete structures are well-known technology for a vast period, but nevertheless, this very technology is a leading solution, currently used in construction industry. Prestressed concrete structures have a huge advantage over conventional methods because it uses the properties of concrete in a very efficient way. The main idea behind this technology is to introduce into the cross-section of the structure, the internal...
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Human-associated bacteria and their mobile genetic elements - important minority in wastewater and wastewater impacted ecosystems
PublicationSince human-associated bacteria have been recognized as vectors in two - way gene transmission between the pathogenic and environmental populations, health hazard connected with wastewater discharge requires reevaluation. In this paper the particular attention was given to antimicrobial-resistance of Escherichia coli and enterococci isolated from wastewater and wastewater impacted environments. The obtained results showed that...
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Electrostatic interactions in finite systems treated with periodic boundary conditions: Application to linear-scaling density functional theory
PublicationWe present a comparison of methods for treating the electrostatic interactions of finite, isolated systems within periodic boundary conditions (PBCs), within density functional theory (DFT), with particular emphasis on linear-scaling (LS) DFT. Often, PBCs are not physically realistic but are an unavoidable consequence of the choice of basis set and the efficacy of using Fourier transforms to compute the Hartree potential. In such...
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Variability of physico-chemical parameters in precipitation in Poland (1996-1999)
PublicationW publikacji przedstawiono wyniki badań przeprowadzonych w latach 1996-1999, dotyczących analizy próbek osadów atmosferycznych zebranych w trzech miejscach pobierania próbek. Zostały one porównane z wynikami otrzymanymi w pięciu innych miejscach na terenie Polski, rozmieszczonych zarówno na terenach objętych ochroną, takich jak parki narodowe, jak również narażonych na silny wpływ zanieczyszczeń pochodzących z aglomeracji miejskich...
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Application of gas chromatographic data and 2D molecular descriptors for accurate global mobility potential prediction
PublicationMobility is a key feature affecting the environmental fate, which is of particular importance in the case of persistent organic pollutants (POPs) and emerging pollutants (EPs). In this study, the global mobility classification artificial neural networks-based models employing GC retention times (RT) and 2D molecular descriptors were constructed and validated. The high usability of RT was confirmed based on the feature selection...
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Small Polymeric Toys Placed in Child-Dedicated Chocolate Food Products—Do They Contain Harmful Chemicals? Examination of Quality by Example of Selected VOCs and SVOCs
PublicationThis study was focused on child-dedicated chocolate food products that contain a plastic package with a small toy inside (also known as chocolate eggs). Three types of these products that are commercially available on the Polish market, with different prices, chocolate composition, and main types of polymers used in the toy manufacturing process, were investigated. The polymers were identified using Fourier-transform infrared (FT-IR)...
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The Changing Nature of In‐Between Spaces in the Transformation Process of Cities
PublicationIn the in‐between spaces of cities, there are many problems of various nature and scale: functional, spatial, economic, environmental, visual, and social. There are also some hidden potentials that can be activated. The aim of the article is to explore the possibilities of solving existing problems and to show the possibilities of using the potentials of in‐between spaces with regard to the changing nature of a city. The article,...
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Joint foreign ownership and global value chains effects on productivity: a comparison of firms from Poland and Germany
PublicationPurpose The study aims to examine the joint effects of foreign ownership (FO) and involvement in global value chains (GVCs) on the productivity performance of firms from a catching-up country (Poland) and a leader economy (Germany). Design/methodology/approach The authors use micro-level data on firms combined with several sector-level GVC participation measures. The authors investigate whether the link between productivity and...
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Enhanced capacitance of composite TiO2 nanotube / boron-doped diamond electrodes studied by impedance spectroscopy
PublicationWe report on the novel composite nanostructures based on boron-doped diamond thin film grown on top of TiO2 nanotubes. The nanostructures made of BDD-modified titania nanotubes showed an increase in activity and performance when used as electrodes in electrochemical environments. The BDD thin films (~200-500 nm) were deposited using microwave plasma assisted chemical vapor deposition (MW PA CVD) onto anodically fabricated TiO2...
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Nucleation and growth of CVD diamond on fused silica optical fibres with titanium dioxide interlayer
PublicationNucleation and growth processes of thin diamond films on fused silica optical fibres have been investigated. Fibres were coated with diamond film using microwave plasma enhanced chemical vapour deposition (µPE CVD) system. Since the growth of diamond on the fused silica glass requires high seeding density, two types of glass pre-treatment were applied: titanium dioxide (TiO2) interlayer deposition and sonication in nanodiamond...
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Przemiany azotu organicznego w komorach osadu czynnego z biologicznym usuwaniem związków biogennych
PublicationW pracy przedstawiono wyniki badań analiz przemian koloidalnego i rozpuszczonego azotu organicznego (CON i DON) zachodzących komorach osadu czynnego z biologicznym usuwaniem związków biogennych. W tym celu wykonano pomiary w skali technicznej (profile w komorach osadu czynnego) oraz badania laboratoryjnych reaktorach nieprzepływowych z osadem pobranym z dwóch oczyszczalni komunalnych zlokalizowanych w północnej Polsce (Gdańsk -...
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CREATIVE PLACEMAKING IN POLAND. CAN ART BECOME AN EFFECTIVE TOOL OF URBAN REGENERATION?!
PublicationThe main aim of the paper is to examine the role of creative placemaking in shaping the urban environment in Polish cities. It also focuses on challenges and obstacles that creative placemaking projects encounter in Polish realities. Creative placemaking is a “micro-development” strategy (Johnson 2009) that focuses on cultural participation, com¬munity engagement and highlights the social role of arts and culture. Artistic interventions...
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Interactive and Media Architecture – From Social Encounters to City Planning Strategies
PublicationThe paper searches into the potential of media and interactive projects to support participation and generate social encounters in public spaces. Moreover, it proposes implementation of media and interactive projects into city planning processes. On the basis of theoretical approaches, case studies and interdisciplinary surveys the paper gives insight how interactive and media architecture can engage people in activities in urban...
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Preliminary Identification of Quantitative Factors Determining the Duration of Court Proceedings in Commercial Cases
PublicationPurpose: The aim of the article was to identify factors that are linear combinations of the variables under scrutiny that affect the duration of court proceedings. Design/Methodology/Approach: This research was conducted on commercial cases, based on the Principal Components Analysis (PCA). The original variables were grouped into factors that are correlated with each other. The Kaiser Criterion (own value >1) was chosen as the...
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Urban Lighting Research Transdisciplinary Framework—A Collaborative Process with Lighting Professionals
PublicationOver the past decades, lighting professionals have influenced the experience of the night by brightly illuminating streets, buildings, skylines, and landscapes 24/7. When this became the accepted norm, a dual perspective on night-time was shaped and the visual enjoyment of visitors after dusk was prioritized over natural nightscapes (nocturnal landscapes). During this time, researchers of artificial light at night (ALAN) observed...
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Advanced Turbine Cycles with Organic Media
PublicationOrganic Rankine Cycle (ORC) power plants have become very popular and have found their applications in systems with renewable sources of energy. So far their overall efficiencies are not very impressive and only for the upper temperature of about 300 °C do they exceed 20%. A drawback of these cycles is the limitation of the cycle upper temperature due to the heat exchanger technology and the materials used. However, it is possible...
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Hyperelastic Microcantilever AFM: Efficient Detection Mechanism Based on Principal Parametric Resonance
PublicationThe impetus of writing this paper is to propose an efficient detection mechanism to scan the surface profile of a micro-sample using cantilever-based atomic force microscopy (AFM), operating in non-contact mode. In order to implement this scheme, the principal parametric resonance characteristics of the resonator are employed, benefiting from the bifurcation-based sensing mechanism. It is assumed that the microcantilever is made...
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Meso‐scale analyses of size effect in brittle materials using DEM
PublicationThe paper describes numerical meso-scale results of a size effect on strength, brittleness and fracture in brittle materials like concrete. The discrete element method (DEM) was used to simulate the size effect during quasi-static splitting tension with the experimental-based meso-structure. The two-dimensional (2D) calculations were carried out on concrete cylindrical specimens with two diameters wherein two different failure...
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Ground-State Entanglement Properties of Helium Atom in a Finite Spherical Cavity
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Geometrically nonlinear finite element simulation of smart piezolaminated plates and shells
PublicationW pracy zaproponowano powłokowy element skończony pozwalający na uwzględnienie efektu piezoelektrycznego. Element został wykorzystany w podejściu Lagrange'a, które wymaga starannego dobrania definicji wielkości mechanicznych i elektrycznych. Zależności przemieszczenie-odkształcenie zbudowano na bazie teorii małych odkształceń i umiarkowanych obrotów. Założono liniowy rozkład pól odkształceń i pola elektrycznego po grubości powłoki....
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Analysis of the Impact Resistance of Toecaps by the Finite Element Method: Preliminary Studies
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Review of constitutive models for technical woven fabrics in finite element analysis
PublicationArtykuł opisuje typy modeli konstytutywnych stosowanych do opisu zachowania się tkanin technicznych w analizie MES. Proponowany jest także warstwowy model sieci gęstej.
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Modeling of the finite amplitude plane wave propagation in non-dissipative medium
PublicationPraca prezentuje wyniki analizy teoretycznej zagadnienia propagacji fali płaskiej o skończonej amplitudzie w ośrodku wodnym bez dyssypacji. Przedstawiono model matematyczny i przykładowe wyniki obliczeń numerycznych. Model matematyczny zbudowano w oparciu o jednowymiarowe równania mechaniki płynów. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Analizowano zmiany ciśnienia i zmiany widma. Badano zbieżność i dokładność...
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Comment on permeability conditions in finite element simulation of bone fracture healing
PublicationThe most popular model of the bone healing considers the fracture callus as poroelastic medium. As such it requires an assumption of the callus’ external permeability. In this work a systematic study of the influence of the permeability of the callus boundary on the simulated bone healing progress is performed. The results show, that these conditions starts to play significant role with the decrease of the callus size. Typically...
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Quantum-correlation breaking channels, broadcasting scenarios, and finite Markov chains
PublicationOne of the classical results concerning quantum channels is the characterization of entanglementbreakingchannels [M. Horodecki et al., Rev. Math. Phys 15, 629 (2003)]. We address the questionwhether there exists a similar characterization on the level of quantum correlations which may gobeyond entanglement. The answer is fully affirmative in the case of breaking quantum correlationsdown to the, so called, QC (Quantum-Classical)...
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Assessment of rod behavior theories used in spectral finite element modeling
PublicationW pracy przedstawiono teorie prętów i przedstawiono ich przydatnośc w analizie propagacji fal sprężystych z wykorzystaniem metody spektralnych elementów skończonych.
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An Enhanced Reduced Basis Method for Wideband Finite Element Method Simulations
PublicationIn this paper, we present a novel strategy for selecting expansion points in the reduced basis method. A single computation of the error estimator is used to select a few expansion points in the multi-parameter space simultaneously. The number of selected points is determined adaptively, based on the accuracy of the current reduced model. The reliability and efficiency of this proposed approach are illustrated by numerical tests...
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Modal energy identification of large stucture idealised by the finite element method
PublicationPrzedstawiono metodę określania energii drgań układów dyskretnych otrzyma-nych w wyniku modelowania metodą elementów skończonych wybranych fragmentów konstrukcji samochodów. W odróżnieniu od poprzednio stosowanych podejść, ro-zważa się całkowite energie mechaniczne odpowiadające poszczególnym posta-ciom drgań własnych. Całkowitą energię mechaniczną oblicza się na podstawie parametrów modelu modalnego. Energię mechaniczną można...
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Modelling of the finite amplitude waves interaction problem inside truncated cone.
PublicationModel matematyczny zjawiska oddziaływania fal o dużej amplitudzie dla przetwornika kołowego zbudowanego w oparciu o równanie KZK. Rozwiązania zagadnienia poszukiwano wewnątrz stożka ściętego. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Podano przykładowe wyniki badań numerycznych.
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Finite difference approximations for nonlinear first order partial differential equations
PublicationKlasyczne rozwiązania nieliniowych równań różniczkowych o pochodnych cząst-kowych pierwszego rzędu są aproksymowane za pomocą równań quasiliniowych uk-ładów równań różniczkowych. Dowód zbieżności wykorzystuje metody porównawcze
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Analysis of unsteady pipe flow using the modified finite element method
PublicationW pracy przedstawiono rozwiązanie równania przepływu nieustalonego zmodyfikowaną metodą elementów skończonych. Podejście to prowadzi do 6-punktowego schematu niejawnego z dwoma parametrami wagowymi. Analiza dokładności wykonana metodą równania zmodyfikowanego wykazała, że zaproponowany schemat zapewnia wyższą dokładność rozwiązania niż inne schematy. Porównanie wyników obliczeń z wynikami eksperymentu fizycznego wskazuje, że ich...
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Finite element modeling of shear localization in granular bodies in hypoplasticity with enhancements
PublicationW pracy omówiono wyniki numeryczne lokalizacji okształceń stycznych w materiałach granulowanych. Obliczenia wykonano stosując prawo hipoplastyczne z rozszerzeniami w ramach mechaniki ośrodka gradientowego, nielokalnego i mikropolarnego. Obliczenia przeprowadzono dla różnych problemów brzegowych z uwzględnieniem lokalizacji. Wyniki analiz porównano z doświadczeniami.
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3-D finite-difference time-domain modelling of ground penetrating radar for identification of rebars in complex reinforced concrete structures
PublicationThis paper presents numerical and experimental investigations to identify reinforcing bars using the ground penetrating radar (GPR) method. A novel element of the paper is the inspection of different arrangements of reinforcement bars. Two particular problems, i.e. detection of few adjacent transverse bars and detection of a longitudinal bar located over or under transverse reinforcement, have been raised. An attention was also...
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Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publication: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
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AN OVERVIEW OF HEAT TRANSFER ENHANCEMENT BASED UPON NANOPARTICLES INFLUENCED BY INDUCED MAGNETIC FIELD WITH SLIP CONDITION VIA FINITE ELEMENT STRATEGY
PublicationThe mathematical model of heat generation and dissipation during thermal energy transmission employing nanoparticles in a Newtonian medium is investigated. Dimensionless boundary layer equations with correlations for titanium dioxide, copper oxide, and aluminium oxide are solved by the finite element method. Parameters are varied to analyze their impact on the flow fields. Various numerical experiments are performed consecutively...
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Discussion on “Coupled effective stress analysis of insertion problems in geotechnics with the Particle Finite Element Method” by L. Monforte, M. Arroyo, J.M. Carbonell, and A. Gens
PublicationAddressed here is the Particle Finite Element Method (PFEM) modelling of undrained CPTu penetration with regard to a reference analytical solution based on the Spherical Cavity Expansion Method (SCEM). Also discussed is the choice of the soil model and its parameters. The effect of cone interface friction on CPTu simulation is analyzed in a series of penetration tests using Arbitrary Lagrangian-Eulerian (ALE) and Updated Lagrangian...
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Cogenerative micro power plants - a new direction for development of power engineering?
PublicationW pracy przedstawiono rozważania dotyczące perspektywy mikrosiłowni domowych w gospodarce rozproszonej. Przedstawiono oryginalne kryterium doboru czynnika roboczego w mikrosiłowni oraz przedstawiono sprawności cieplne i egzergetyczne obiegów Clausiusa-Rankina realizujących pracę mikrosiłowni.
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An Approach for Journal Summarization Using Clustering Based Micro-Summary Generation
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Growth Orientation of Women and Men Owners of Micro Firms in the Pomerianian Region
PublicationDespite the fact that research on women’s entrepreneurship has been conducted for many years, still many clear answers to questions about the differences between entrepreneurs of both genders are missing. One of the unresolved issues is the performance of women in entrepreneurship. The aim of the study is to investigate the growth orientation of microenterprises operating in the Pomeranian region in Poland and to compare its level...
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Enhanced energy conversion as a result of fluid-solid interaction in micro- and nanoscale
PublicationIt is known that nano- and micromechanics require new approaches to right describing of surface-like phenomena which lead to an enhanced energy conversion. In this work, a general form of surface forces that consist of a contribution from both the friction and mobility components has been extended to collect the effects of bulk and surface motion of a fluid. Quite similar impact can be observed for a solid-fluid mixture, where...
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MicroGal Gravity Measurements with MGS-6 Micro-g LaCoste Gravimeter
PublicationKnowing the exact number of fruit and trees helps growers to make better decisions about how to manage their production in the orchard and prevent plant diseases. The current practice of yield estimation is to manually count fruit or flowers (before harvesting), which is a very time-consuming and costly process. Moreover it’s not practical for large orchards. It also doesn’t allow to make predictions of plant development in a more...
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Special techniques and future perspectives: Simultaneous macro- and micro-electrode recordings
PublicationThere are many approaches to studying the inner workings of the brain and its highly interconnected circuits. One can look at the global activity in different brain structures using non-invasive technologies like positron emission tomography (PET) or functional magnetic resonance imaging (fMRI), which measure physiological changes, e.g. in the glucose uptake or blood flow. These can be very effectively used to localize active patches...
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GVC involvement and the gender wage gap: Micro -evidence on European countries
PublicationWe examine linkages between involvement in global value chains (GVCs) and gender wage inequalities. We use merged data from Structure of Earnings Survey and the World Input Output Database covering 18 European countries. We employ information on employees’ personal and company characteristics and a sectoral involvement in GVCs. In general, the wages of workers from sectors more involved in GVCs are lower. However, the relationship...
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Modeling of textural anisotropy in granular materials with stochastic micro-polar hypoplasticity.
PublicationW artykule przedstawiono wyniki numerycznej wpływu anizotropii strukturalnej w materiałach granulowanych na powstawanie lokalizacji odkształceń. Obliczenia wykonano dla ściskania w płaskim stanie odkształcenia stosując metodę elementów skończonych na bazie mikropolarnego prawa hipoplastycznego. Wpływ anizotropii modelowano stosując skorelowane pola początkowego wskaźnika porowatości.
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Investigations of micro-structure evolution in granular shear zones using DEM.
PublicationW artykule pokazano rozwój różnych zjawisk mikrostrukturalnych na poziomie ziarna podczas parcia piasku na sztywną ściankę przemieszczającą się poziomo. Obliczenia wykonano stosując metodę DEM. Wyniki na poziomie globalnym porównano z wynikami doświadczalnymi i wynikami MES. Szczególna uwagę zwrócono na rozwój wirów w strefach ścinania.
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Size effects in problems of footings on sand within micro-polar hypoplasticity.
PublicationW artykule przedstawiono obliczenia efektów skali na nośność fundamentu na piasku. Obliczenia wykonano przy pomocy mikropolarnego prawa hipoplastycznego. W obliczeniach wykorzystano stochastyczne rozkłady początkowego wskaźnika porowatości według rozkładu Gaussa oraz różne wymiary fundamentu.
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Optical recognition elements. Macrocyclic imidazole chromoionophores entrapped in silica xerogel
PublicationNowe chromojonofory zawierające fragment eteru koronowego i resztę azolu zostały unieruchomione w krzemionkowej matrycy żelowej metodą zol-żel i zbadane jako optyczne elementy rozpoznające kationy Li+,Cs+, Cu2+. Elementy optyczne oparte na 21-członowych pochodnych imidazolu i 4-metyloimidazolu rozpoznawały jony Li+ w roztworze wodnym. Wyznaczono parametry g i A na podstawie badań EPR dla kompleksów 18-członowej i 21-członowej pochodnej...