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Search results for: groundwater flow, particle size distribution, soil permeability
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Effect of alkyl sulfate on the phase behavior of microemulsions stabilized with monoacylglycerols
PublicationIn this study the effect of an anionic surfactant (sodium dodecyl sulfate SDS) and oils (hydrocarbons: C12-C16) on the formation and phase behavior of the systems of oil/monoacylglycerols (MAG):SDS/propylene glycol/water has been investigated. The effects of the surfactant mixture on the phase behavior and the concentrationof water or oil in the systems were studied at three temperatures (50, 55, 60 C). Electrical conductivity...
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Synthesis and modification of reduced graphene oxide aerogels for biofuel cell applications
PublicationWe have carried out the preparation of reduced graphene oxide aerogels using eco-friendly method that is based on the Hummers method of graphite oxidation without the use of NaNO3 that produces toxic gases. To obtain a porous 3D structure of reduced graphene oxide, we performed the hydrothermal reduction at elevated temperature. We also prepared the rGO aerogel/CNT composite using multiwalled carbon nanotubes as linkers. The rGO...
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Local impedance imaging of boron-doped polycrystalline diamond thin films
PublicationLocal impedance imaging (LII) was used to visualise surficial deviations of AC impedances in polycrystalline boron-doped diamond (BDD). The BDD thin film electrodes were deposited onto the highly doped silicon substrates via microwave plasma-enhanced CVD. The studied boron dopant concentrations, controlled by the [B]/[C] ratio in plasma, ranged from 1 × 1016 to 2 × 1021 atoms cm−3. The BDD films displayed microcrystalline structure,...
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Non-conventional approach in single-sided lapping process: kinematic analysis and parameters optimization
PublicationThe lapping process is strongly affected by a number of input parameters. One of the fundamental mechanical processes in lapping is the abrasive effect of particles. In order to examine the influence of the kinematic parameters on the lapping uniformity of unconventional single-sided machine, numerical simulations of particles sliding trajectories are performed. Changing the kinematic parameters, e.g., rotational velocities or...
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Effect of annealing temperature on slurry erosion resistance of ferritic X10CrAlSi18 steel
PublicationIn the present work, the slurry erosion tests were carried out to investigate the influence of heat treatment on slurry erosion process of ferritic X10CrAlSi18 stainless steel using a slurry pot test rig. X10CrAlSi18 stainless steel was tested in as-received condition and after annealing at three different temperatures: 600°C, 800°C and 1000°C. Degradation of materials due to slurry erosion depends on many factors connected with...
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Torsional elasticity and energetics of F1-ATPase
PublicationFoF1-ATPase is a rotary motor protein synthesizing ATP from ADP driven by a cross-membrane proton gradient. The proton flow through the membrane-embedded Fo generates the rotary torque that drives the rotation of the asymmetric shaft of F1. Mechanical energy of the rotating shaft is used by the F1 catalytic subunit to synthesize ATP. It was suggested that elastic power transmission with transient storage of energy in some compliant...
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Effects of polymer sealant interlayer on quality of EN AW-2024-T3 aluminum alloy lap joint prepared by friction stir welding
PublicationThis study investigates the influence of polymer interlayers on the mechanical properties and fracture behavior of friction stir welded EN AW-2024-T3 aluminum alloy joints. Aqualock AL 6002 (Adhesive_1) and 3M Adhesion Promoter 86A (Adhesive_2) were selected as polymeric sealants for EN AW-2024-T3 aluminum alloy interfaces. Force analysis revealed that the choice of polymer interlayer significantly affects the axial force during...
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Development of an asymmetric cellulose acetate-ionic liquid P6,6,6,14[PHOS] gel membrane for the perstraction of succinic acid from a model fermentation solution of yarrovia lipolytica
PublicationThis study introduces a novel approach to separate succinic acid (SA) from fermentation mixtures using an asymmetric membrane based on the gelation of the ionic liquid [P6,6,6,14][PHOS] coated with two layers of cellulose acetate. The membrane was designed to explore the synergistic effect of polymer-ionic liquid interfaces according to the solution-diffusion theory. The gelation of the ionic liquid was achieved using 12-hydroxystearic...
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Recent Advances in Loop Heat Pipes with Flat Evaporator
PublicationThe focus of this review is to present the current advances in Loop Heat Pipes (LHP) with flat evaporators, which address the current challenges to the wide implementation of the technology. A recent advance in LHP is the design of flat-shaped evaporators, which is better suited to the geometry of discretely mounted electronics components (microprocessors) and therefore negate the need for an additional transfer surface (saddle)...
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Curved Surface Minijet Impingement Phenomena Analysed with ζ-f Turbulence Model
PublicationThe jet impingement phenomenon plays an important role among the heat transfer intensification methods. Very often its application and analyses refer to simple flat surfaces, while there is a lack of information in the literature for cases addressing curved surfaces. In the present work, the single jet impingement on the non-flat (concave and convex) surface is studied for a wide range of geometries, which originate from the mini-jet...
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Some aspects of the constitutive modelling of natural fine grained soils
PublicationThe monograph deals with selected problems of the constitutive modelling of natural fine grained soils commonly known as clays. The main idea is not to propose a unified model which is capable of describing all known features of mechanical behaviour of fine grained soils. Instead, separate models are proposed describing the mechanical behaviour of heavily overconsolidated, lightly overconsolidated and normally consolidated clays....
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NUTRITIONAL AND PHARMACEUTICAL APPLICATIONS OF BIOACTIVE COMPOUNDS IN TROPICAL FRUITS
PublicationDuring the past two decades our international scientific group investigated in vitro the physicochemical and nutritional characteristics of some cultivars of durian at various stages of ripening, mangosteen and new cultivars of snake fruit in comparison with widely used avocado, kiwifruit and mango, and in vivo their influence on laboratory animals. The main objective of the present study was to screen and compare the properties...
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Characterization methods of nickel nano-particles obtained by the ex-solution process on the surface of Pr, Ni-doped SrTiO3 perovskite ceramics
PublicationIn this paper, a novel electrode material based on Pr, Ni co-doped strontium titanate ( Sr0.7Pr0.3)xTi1−yNiyO3 with constant amount of 30% praseodymium dopant, different amount of nickel (y = 0.06 and y = 0.10) and additional nonstoichiometry in Sr-site (x = 1; x = 0.9 and x = 0.8) was investigated as fuel electrode for SOEC devices. A porous ceramics were prepared by solid-state reaction method. X-ray diffraction measurements...
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Impact of Innovative Financial Products on Financial Systems: Exchange Traded Products and the Polish Financial System
PublicationExchange Traded Products (ETPs) are one of the most recent and most rapidly developing financial products. As their assets grow they have an increasing impact on financial systems in many countries, including USA, UK or Japan. Development of ETPs is linked with many opportunities and threats for the local financial systems. Their correct assessment is becoming more difficult due to the growing complexity of the available products,...
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Effect of the ex situ physical and in situ chemical modification of bacterial nanocellulose on mechanical properties in the context of its potential applications in heart valve design
PublicationBacterial nanocellulose (BNC) is a promising material for heart valve prostheses. However, its low strength properties limit its applicability in cardiovascular surgery. To overcome these limitations, the mechanical properties of BNC can be improved through modifications. The aim of the research was to investigate the extent to which the mechanical properties of BNC can be altered by modifying its structure during its production...
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Image Classification Based on Video Segments
PublicationIn the dissertation a new method for improving the quality of classifications of images in video streams has been proposed and analyzed. In multiple fields concerning such a classification, the proposed algorithms focus on the analysis of single frames. This class of algorithms has been named OFA (One Frame Analyzed).In the dissertation, small segments of the video are considered and each image is analyzed in the context of its...
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Temperature Evolution, Material Flow, and Resulting Mechanical Properties as a Function of Tool Geometry during Friction Stir Welding of AA6082
PublicationThe friction stir welding process was simulated for joining AA6082 aluminum alloy with the use of the computational fluid dynamics method. Two different tool geometries were used—a tapered cylindrical pin (simple pin) and a hexagonal pin with grooves (complex pin). The analysis of the simulations performed was discussed in terms of temperature evolution during the process, total heat input, residual stresses and material flow....
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Development of advanced machine learning for prognostic analysis of drying parameters for banana slices using indirect solar dryer
PublicationIn this study, eXtreme Gradient Boosting (XGBoost) and Light Gradient Boosting (LightGBM) algorithms were used to model-predict the drying characteristics of banana slices with an indirect solar drier. The relationships between independent variables (temperature, moisture, product type, water flow rate, and mass of product) and dependent variables (energy consumption and size reduction) were established. For energy consumption,...
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Effect of surface roughness on thermal-hydraulic characteristics of plate heat exchanger
PublicationIn the paper the experimental analysis of passive heat transfer intensification in the case of modeled plate heat exchanger is conducted. The plate heat exchanger is chosen for the analysis because this kind of heat exchangers could be prospectively applied in the ORC systems, however other areas or application are equally possible. The experimental setup was assembled at the Department of Energy and Industrial Apparatus of Gdansk...
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A facile approach to fabricate load-bearing porous polymer scaffolds for bone tissue engineering
PublicationBiodegradable porous scaffolds with oriented interconnected pores and high mechanical are load-bearing biomaterials for bone tissue engineering. Herein, we report a simple, non-toxic, and cost-effective method to fabricate high-strength porous biodegradable scaffolds, composed of a polymer matrix of polycaprolactone (PCL) and water-soluble poly (ethylene oxide) (PEO) as a sacrificial material by integrating annealing treatment,...
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Smartphone-Assisted and Optical Quantification of Copper and Glucose Using Palm Wine-Tailored Carbon Dots and Their Multiple Logic Gate Application
PublicationIn this work, potassium, sulfur, nitrogen, and chlorine self-doped carbon dots (CDs) were hydrothermally synthesized using palm wine as a carbon source. The palm wine-derived CDs (PW-CDs) are amorphous in nature and displayed an average particle size of 4.19 ± 0.89 nm. The as-synthesized CDs are used to fabricate a photoluminescent sensing probe to simultaneously detect Cu2+ and glucose via the “Turn ON−OFF−ON” mechanism. The PL...
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Testing Stability of Digital Filters Using Optimization Methods with Phase Analysis
PublicationIn this paper, novel methods for the evaluation of digital-filter stability are investigated. The methods are based on phase analysis of a complex function in the characteristic equation of a digital filter. It allows for evaluating stability when a characteristic equation is not based on a polynomial. The operation of these methods relies on sampling the unit circle on the complex plane and extracting the phase quadrant of a function...
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The impact of global value chains on wages, employment, and productivity: a survey of theoretical approaches
PublicationThis study presents a systematic literature review to provide a collection of theories explaining the impact of global value chains (GVCs) on labour market outcomes. Due to the complex nature of GVCs and the interconnectedness of wages, employment, and productivity, many direct and indirect effects are at play. To ensure a transparent and systematic flow of the review process, I follow the PRISMA guide. Eventually, 36 records out...
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Role of Silicon in Counteracting Cadmium Stress in Pea Plants (Pisum sativum L.): Insights Into Cadmium Binding Mechanisms and Pectin Methylesterase Activity
PublicationPurpose: The aim of this study was to investigate the role of silicon (Si) in counteracting a cadmium (Cd) stress to pea plants (Pisum sativum L.) and to identify the mechanism by which Cd is bound within pea roots. Methods: These goals were achieved through (i) a histochemical study of Cd localization in pea roots, (ii) spectrophotometric determination of pectin content and the activity...
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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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Stable and degradable microgels linked with cystine for storing and environmentally triggered release of drugs
PublicationEnvironmentally sensitive, degradable microgels based on poly(N-isopropylacrylamide) (pNIPA) crosslinked with the diacryloyl derivative of cystine (BISS) were synthesized by applying surfactant-free emulsion polymerization. pNIPA contributed the sensitivity to temperature to the microgels and the cross-linker made them degradable and sensitive to pH. The morphology of the microgels was investigated by using scanning and transmission...
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Microwave radiation in the synthesis of urethane prepolymers
PublicationThis paper describes the use of microwave radiation in the synthesis of urethane prepolymers in bulk (without solvent). The prepolymers were synthesized using 1,6-hexamethylene diisocyanate (HDI) and poly (ε-caprolactone) diol (PCL) at a molar ratio of 4:1. The reaction was carried out without a catalyst in the reactor with a conventional heating system (oil bath) or in the microwave reactor (MW Reactor NOVA 09) at temperatures...
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CZYNNIKI DECYDUJĄCE O PRZYDATNOŚCI KOMPUTEROWEGO MODELU PRZEPŁYWÓW W SIECI WODOCIĄGOWEJ
PublicationW pracy poddano analizie wielozadaniowy proces tworzenia komputerowego modelu przepływów. W efekcie zidentyfikowano szereg czynników ograniczających obszar stosowania modelu w praktyce inżynierskiej. W zakresie pozyskiwania danych strukturalnych i operacyjnych wskazano potencjalne źródła błędów, które przyczyniają się do zmniejszenia dokładności odwzorowania stanu rzeczywistego. Specjalną rangę nadano specyfikacji czynników związanych...
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Magnetic photocatalysts for water treatment
PublicationThe concept of magnetic photocatalysts with separation function requires ferromagnetic material with high magnetic susceptibility to an external magnetic field to enable recycling of composite nanoparticles. Currently, much attention is devoted to functionalization of photocatalyst using MFe2O3, where M =Fe, Zn, Co, Mn. However direct contact between photocatalyst and magnetic iron oxide particles leads to photodissolution of iron...
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A Perspective on Missing Aspects in Ongoing Purification Research towards Melissa officinalis
PublicationMelissa officinalis L. is a medicinal plant used worldwide for ethno-medical purposes. Today, it is grown everywhere; while it is known to originate from Southern Europe, it is now found around the world, from North America to New Zealand. The biological properties of this medicinal plant are mainly related to its high content of phytochemical (bioactive) compounds, such as flavonoids, polyphenolic compounds, aldehydes, glycosides...
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Development and Validation of SPE-HPLC-MS/MS Method for Determining Cyclophosphamide in Surface Waters
PublicationA rapid and selective method for trace amounts determination of cyclophosphamide in surface water samples has been developed. A solid phase extraction SPE method for extraction and clean-up procedure has been optimized for determination by reversed-phase high-performance liquid chromatography with tandem mass spectrometry. The analyses proceed in the positive ion mode by means of the electrospray ionization method (ESI). Clean...
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The hydrogen bond network structure within the hydration shell around simple osmolytes: Urea, tetramethylurea, and trimethylamine-N-oxide, investigated using both a fixed charge and a polarizable water model
PublicationDespite numerous experimental and computer simulation studies, a controversy still exists regarding the effect of osmolytes on the structure of surrounding water. There is a question, to what extent some of the contradictory results may arise from differences in potential models used to simulate the system or parameters employed to describe physical properties of the mixture and interpretation of the results. Bearing this in mind,...
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The hydrogen bond network structure within the hydration shell around simple osmolytes: Urea, tetramethylurea, and trimethylamine-N-oxide, investigated using both a fixed charge and a polarizable water model
PublicationDespite numerous experimental and computer simulation studies, a controversy still exists regarding the effect of osmolytes on the structure of surrounding water. There is a question, to what extent some of the contradictory results may arise from differences in potential models used to simulate the system or parameters employed to describe physical properties of the mixture and interpretation of the results. Bearing this in mind,...
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Estimation of the Regenerative Braking Process Efficiency in Electric Vehicles
PublicationIn electric and hybrid vehicles, it is possible to recover energy from the braking process and reuse it to drive the vehicle using the batteries installed on-board. In the conditions of city traffic, the energy dissipated in the braking process constitutes a very large share of the total resistance to vehicle motion. Efficient use of the energy from the braking process enables a significant reduction of fuel and electricity consumption...
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c-Myc inhibition and p21 modulation contribute to unsymmetrical bisacridines-induced apoptosis and senescence in pancreatic cancer cells
PublicationBackground Pancreatic cancer (PC) is one of the most aggressive cancers and is the seventh leading cause of cancer-related death worldwide. PC is characterized by rapid progression and resistance to conventional treatments. Mutations in KRAS, CDKN2A, TP53, SMAD4/DPC4, and MYC are major genetic alterations associated with poor treatment outcomes in patients with PC. Therefore, optimizing PC therapy is a tremendous challenge. Unsymmetrical...
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Effect of Coating Material Properties on Tilting-pad Thrust Bearing Performance
PublicationPolymer lined tilting-pad bearings demonstrate many advantages over traditional bearing systems. Bearings with a polymer layer in comparison with a babbitted layer show, for example: lower value of friction coefficient (important during start/stops), higher fatigue strength of the coating, better distribution of the load on individual pads due to lower elasticity of the polymers, wider range of operational temperatures or the ability...
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Types of Markov Fields and Tilings
PublicationThe method of types is one of the most popular techniques in information theory and combinatorics. However, thus far the method has been mostly applied to one-dimensional Markov processes, and it has not been thoroughly studied for general Markov fields. Markov fields over a finite alphabet of size m ≥ 2 can be viewed as models for multi-dimensional systems with local interactions. The locality of these interactions is represented...
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AVAILABILITY CONDITIONS AS A CRITICAL FACTOR IN PRODUCT CATEGORY MANAGEMENT IN SHAPING THE OFFER OF NON-ALCOHOLIC EQUIVALENTS OF ALCOHOLIC BEVERAGES
PublicationPurpose: To determine the availability of non-alcoholic wines and spirit substitutes in various distribution channels and understand the factors shaping store assortments to identify potential product strategies in category management. Design/methodology/approach: A literature review using desk research and a two-part study on the availability of non-alcoholic substitutes, utilizing observation and interview methods. Findings:...
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Influence of the boron doping level on the electrochemical oxidation of the azo dyes at Si/BDD thin film electrodes
PublicationIn this study the efficiency of electrochemical oxidation of aromatic pollutants, such as reactive dyes, at boron-doped diamond on silicon (Si/BDD) electrodes was investigated. The level of [B]/[C] ratio which is effective for the degradation and mineralization of selected aromatic pollutants, and the impact of [B]/[C] ratio on the crystalline structure, layer conductivity and relative sp3/sp2 coefficient of a BDD electrode were...
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Spatio-temporal filtering for determination of common mode error in regional GNSS networks
PublicationThe spatial correlation between different stations for individual components in the regional GNSS networks seems to be significant. The mismodelling in satellite orbits, the Earth orientation parameters (EOP), largescale atmospheric effects or satellite antenna phase centre corrections can all cause the regionally correlated errors. This kind of GPS time series errors are referred to as common mode errors (CMEs). They are usually...
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Temperature-controlled nanomosaics of AuCu bimetallic structure towards smart light management
PublicationGold–copper nanostructures are promising in solar-driven processes because of their optical, photocatalytic and photoelectrochemical properties, especially those which result from the synergy between the two metals. Increasing interest in their internal structure, such as the composition or distribution of the Au and Cu as well as the size and shape of the nanoparticles, have developed to define their physicochemical properties. In...
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Investigation of Mechanical and Microstructural Properties of Welded Specimens of AA6061-T6 Alloy with Friction Stir Welding and Parallel Friction Stir Welding Methods
PublicationThe present study investigates the effect of two parameters of process type and tool offset on tensile, microhardness, and microstructure properties of AA6061-T6 aluminum alloy joints. Three methods of Friction Stir Welding (FSW), Advancing Parallel-Friction Stir Welding (AP-FSW), and Retreating Parallel-Friction Stir Welding (RP-FSW) were used. In addition, four modes of 0.5, 1, 1.5, and 2 mm of tool offset were used in two welding...
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Direct injection liquid chromatography-mass spectrometry (DI-LC-MS) analysis for rapid lipidomic profiling of extracellular vesicles
PublicationExtracellular vesicles (EVs) are small, spherical particles produced by eukaryotic and prokaryotic cells, surrounded by a bilayer membrane and carrying various bioactive molecules, such as proteins, surface receptors, membrane and soluble proteins, lipids, and nucleic acids. EVs are of substantial interest because of their important roles in cell communication, epigenetic regulation and possible application in disease diagnosis...
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Investigations on fracture in reinforced concrete beams in 3-point bending using continuous micro-CT scanning
PublicationThis study explores a fracture process in rectangular reinforced concrete (RC) beams subjected to quasi-static three-point bending. RC beams were short and long with included longitudinal reinforcement in the form of a steel or basalt bar. The ratio of the shear span to the effective depth was 1.5 and 0.75. The focus was on the load–deflection diagram and crack formation. Three-dimensional (3D) analyses of the size and distribution...
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Stateczność fundamentów bezpośrednich posadowionych na zboczu z gruntu zbrojonego.
PublicationW monografii przedstawiono i przeanalizowano aktualny stan wiedzy oraz zaproponowano własną metodykę opartą na koncepcji ESE (Experimental Soil Engineering) dotyczącą obliczeń nośności i osiadania - a więc kompleksowego sprawdzenia stateczności - fundamentów bezpośrednich posadowionych na koronie zbocza z gruntu bez zbrojenia i z gruntu zbrojonego. Studia bibliograficzne (rozdział 2) objęły przeanalizowanie jakościowych i ilościowych...
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Modelling Signalised Intersections Reliability of Functioning
PublicationThe article addresses a fundamental aspect of traffic, i.e. the operation of traffic signals at intersections, in reference to the reliability theory. In many cases, when intersections carry substantial amounts of traffic, selecting control parameters to produce satisfactory traffic conditions is quite difficult. Design methods do not cover all possible situations which are the result of intersection geometry and location...
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Activated Tungsten Inert Gas Weld Characteristics of P91 Joint for Advanced Ultra Supercritical Power Plant Applications
PublicationActivated Tungsten Inert Gas (A-TIG) welding, a variant of tungsten inert gas (TIG) welding, was used for welding P91. In Generation IV power plants, P91 welds are prone to premature failure due to the presence and formation of brittle phases and creep at high temperatures. When performing A-TIG welding, the flux composition plays a role in the reversal of the Marangoni flow in the weld pool, which ultimately determines the level...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part II: Statistical Analysis and Interpretation of Tests
PublicationThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, and vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate (PET) bottles are increasingly used in this technology. In this paper, the main aim is to describe and interpret the results of statistical analysis of the influence of the temperature of...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part I: Research Methodology and Results
PublicationThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate bottles, commonly called PET, are increasingly used in this technology. In this paper, the main aim is to describe the statistical analysis methodology of the influence of the temperature of the...
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Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development
Publicationfirst_pageDownload PDFsettingsOrder Article Reprints Open AccessArticle Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development by Bartłomiej Michał Cieślik 1,*ORCID,Oskar Ronda 1ORCID,Elżbieta Grządka 2ORCID,Jolanta Orzeł 2 andJustyna Płotka-Wasylka 1 1 Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela...