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Slurry Surfacing Mixes on the Basis of Bitumen Modified with Phenol-Cresol-Formaldehyde Resin
PublikacjaSlow-breaking monophase cationic bitumen emulsions have been produced on the basis of bitumen modified with phenol-cresol-formaldehyde resin (PhCR-F). Bitumen emulsions were used as a binder for thin-layer coatings with slurry surfacing mixes (SSM). Physical and technical parameters of modified and unmodified emulsions were determined and analyzed. The optimal compositions of SSM were selected according to the breaking criterion....
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Removal efficiency of phenol by ozonation process with calcium peroxide from aqueous solutions
PublikacjaPhenol has been introduced as a priority pollutant by the US Environmental Protection Agency. Advanced oxidation processes (AOPs) are one of the most efcient methods for removal of non-degradable organic pollutants in aqueous solutions. The removal efciencies of phenol and COD under optimal conditions pH=3, phenol concentration=5 mg/L, CaO2 concentration=0.025 mg/L, temperature 25 °C, 1 g/min ozonation rate and contact time=90...
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OBTAINING OF COUMARONE-INDENE RESINS BASED ON LIGHT FRACTION OF COAL TAR 3. COUMARONE-INDENE RESINS WITH METHACRYLIC FRAGMENTS
PublikacjaThe method for obtaining coumarone-indene resins with methacrylic fragments (CIRM) was developed with the addition of methyl ethacrylate, using a light fraction of coal tar and its fraction boiling within 423–463 К. CIRM was obtained via radical cooligomerization using 2,2'-azobis (2-methyl-propionitrile) as the initiator. The effect of the initiator amount, temperature and reaction time on the yield, softening temperature and...
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Obtaining of coumarone-indene resins based on light fraction of coal tar.1. Coumarone-indene resins with carboxy groups
PublikacjaCoumarone-indene resins (CIR) with carboxy groups were synthesized via cooligomerization of unsaturated compounds presented in ligh fraction of coal tar and its fraction boiling out within 423-463 K with the addition of such industrial monomers as styrene, maleic anhydride, glycidyl methacrlate and methacryclic acid. 2,2-azobs 92-methylpropionitrile) in the form of 0,2 M solution in toluene was used as an initiator. The effect...
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Obtaining of coumarone-indene resins based on light fraction of coal tar 2. Coumarone-indene resins with epoxy groups
PublikacjaCoumarone-indene resins (CIR) with carboxy groups were synthesized via cooligomerization of unsaturated compounds presented in light fraction of coal tar and its fraction boiling out within 423–463 K with the addition of such industrial monomers as styrene, maleic anhydride, glycidyl methacrylate and methacrylic acid. 2,2`-Azobis(2-methylpropionitrile) in the form of 0.2 M solution in toluene was used as an initiator. The effect...
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The Influence of COD Fraction Forms and Molecules Size on Hydrolysis Process Developed by Comparative OUR Studies in Activated Sludge Modelling
PublikacjaThe activated sludge models (ASMs) commonly used by the International Water Association (IWA) task group are based on chemical oxygen demand (COD) fractionations. However, the proper evaluation of COD fractions, which is crucial for modelling and especially oxygen uptake rate (OUR) predictions, is still under debate. The biodegradation of particulate COD is initiated by the hydrolysis process, which is an integral part of an ASM....
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Effects of Noncontact Shoulder Tool Velocities on Friction Stir Joining of Polyamide 6 (PA6)
PublikacjaIn this study, the effects of the traverse and rotational velocities of the noncontact shoulder tool on the heat generation and heated flux during the friction stir joining of high-density polyamide 6 (PA6) polymer were investigated. The computational fluid dynamics (CFD) method was employed to simulate the thermomechanical phenomena during the friction stir joining (FSJ) process of PA6. A developed model was used to consider the...
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Multimodal analysis of traction forces and the temperature dynamics of living cells with a diamond-embedded substrate
PublikacjaCells and tissues are constantly exposed to chemical and physical signals that regulate physiological and pathological processes. This study explores the integration of two biophysical methods: traction force microscopy (TFM) and optically detected magnetic resonance (ODMR) to concurrently assess cellular traction forces and the local relative temperature. We present a novel elastic substrate with embedded nitrogen-vacancy microdiamonds...
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Continuum contact model for friction between graphene sheets that accounts for surface anisotropy and curvature
PublikacjaUnderstanding the interaction mechanics between graphene layers and co-axial carbon nanotubes (CNTs) is essential for modeling graphene and CNT-based nanoelectromechanical systems. This work proposes a new continuum contact model to study interlayer interactions between curved graphene sheets. The continuum model is calibrated and validated using molecular dynamics (MD) simulations. These are carried out employing the reactive...
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Influence of friction stir welding technological parameters on the properties of the joints of selected aluminum alloys
PublikacjaThe purpose of this dissertation was to determine the effect of friction stir welding technological parameters on the properties of selected aluminum alloy joints, with consideration of the residual stresses and dislocation density in the joints. The goal of the present work was also to produce defect-free joints with high mechanical and electrochemical properties. In the dissertation, similar welds of AA6082 alloy and dissimilar...
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Torque Transmitted by Multi-plate Wet Clutches in Relation to Number of Friction Plates and Their Dimensions
PublikacjaIn the paper results of experimental tests on multi-plate wet clutch torque capacity for various diameters and numbers of friction plates are presented. Construction of an apparatus for laboratory tests of wet clutch engagement, drag torque and maximum torque is shown. Methodology of maximum torque capacity experiment and hydraulic circuit diagram, which supplies a motor and an actuator for the experiment are described. Analytically...
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Manufacturing Parameters, Materials, and Welds Properties of Butt Friction Stir Welded Joints–Overview
PublikacjaThe modern and eco-friendly friction stir welding (FSW) method allows the combination of even such materials that are considered to be non-weldable. The development of FSW technology in recent years has allowed a rapid increase in the understanding of the mechanism of this process and made it possible to perform the first welding trials of modern polymeric and composite materials, the joining of which was previously a challenge....
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Torque capacity of multidisc wet clutch with reference to friction occurrence on its spline connections
PublikacjaIn this article developed mathematical model that includes friction occurrence on spline connections is presented. The work also contains results of experimental research on torque capacity of multidisc wet clutch. These results are expressed as a function of contact pressure for different number of friction surfaces. Due to increased interest in research concerning multidisc wet clutches it is essential to determine impact of...
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Study on Dry Sliding Wear and Friction Behaviour of Al7068/Si3N4/BN Hybrid Composites
PublikacjaHybrid aluminium metal matrix composites have the potential to replace single reinforced aluminium metal matrix composites due to improved properties. Moreover, tribological performance is critical for these composites, as they have extensive application areas, such as the automotive, aerospace, marine and defence industries. The present work aims to establish the tribological characteristics of Al7068/Si3N4/BN hybrid metal matrix...
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Friction Stir Welding of Aluminum in the Aerospace Industry: The Current Progress and State-of-the-Art Review
PublikacjaThe use of the friction stir welding (FSW) process as a relatively new solid-state welding technology in the aerospace industry has pushed forward several developments in different related aspects of this strategic industry. In terms of the FSW process itself, due to the geometric limitations involved in the conventional FSW process, many variants have been required over time to suit the different types of geometries and structures,...
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Partition of friction heat between sliding semispaces due to adhesion-deformational heat generation
PublikacjaAnalytical expressions of heat-partition coefficient and contact temperatures for two sliding semispaces with account for adhesion-deformational heat generation and contact heat exchange have been obtained. The rate of deformational heat generation is assumed to decay exponentially with increase of distance from the interface. It has been shown that heat-generation configuration and the intensity of contact heat exchange have impact...
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Correlations between the wear of car brake friction materials and airborne wear particle emissions
PublikacjaAirborne wear particles emitted from transport vehicle brakes are one of the main sources of toxic metals in inhalable particulate matter. Prediction of wear particle emissions may become more accurate if the relationship between the wear and particle emission characteristics is known. An experimental study was performed to investigate proportional correlations between the mass wear, 0.01–0.42 μm particle emission measured by a NanoScan...
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Fractional Calculus Evaluation of Hyaluronic Acid Crosslinking in a Nanoscopic Part of Articular Cartilage Model System
PublikacjaThis work presents a study of the mechanism of physical crosslinking of hyaluronic acid in the presence of common phospholipids in synovial joint organ systems. Molecular dynamic simulations have been executed to understand the formation of hyaluronan networks at various phospholipid concentrations. The results of the simulations suggest that the mechanisms exhibit subdiffusion characteristics. Transportation quantities derive...
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Airfoil Design Under Uncertainty Using Non-Intrusive Polynomial Chaos Theory and Utility Functions
PublikacjaFast and accurate airfoil design under uncertainty using non-intrusive polynomial chaos (NIPC) expansions and utility functions is proposed. The NIPC expansions provide a means to efficiently and accurately compute statistical information for a given set of input variables with associated probability distribution. Utility functions provide a way to rigorously formulate the design problem. In this work, these two methods are integrated...
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Fractional-Order PID Controller (FOPID)-Based Iterative Learning Control for a Nonlinear Boiler System
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New type of repeated Si–C-podand catalysts for solid–liquid phase transfer reactions
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Proton transfer reactions from some diarylcyanomethanes to cis 1,2-bis(diethylaminomethyl)cyclohexane in acetonitrile
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Modelling of First- and Second-order Chemical Reactions on ARUZ – Massively-parallel FPGA-based Machine
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Guidelines regarding ineffective maintenance of organ functions (futile therapy) in paediatric intensive care units
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Facile Deposition of Pd Nanoparticles on Carbon Nanotube Microparticles and Their Catalytic Activity for Suzuki Coupling Reactions
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Single Triglyceride-Rich Meal Destabilizes Barrier Functions and Initiates Inflammatory Processes of Endothelial Cells
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Self-adjusting sub-sample delay estimator based on fractional delaying Hilbert transform filter
PublikacjaZaprezentowano nowe rozwiązanie samo-nastrajalnego estymatora opóźnienia sygnału sinusoidalnego, działającego w czasie dyskretnym. Zastosowano filtr Hilberta o skończonej odpowiedzi ipulsowej (FIR od ang. finite impulse response) zagregowany z filtrem ułamkowo-opóźniającym. Zilustrowano performancję estymatora, również w obecności szumu. Przeanalizowano jego złożoność numeryczną.
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Is participation in music festivals a self-expansion opportunity? Identity, self-perception, and the importance of music’s functions
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Hybrid super‐twisting fractional‐order terminal sliding mode control for rolling spherical robot
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Reactions of NO2 with chromium(III) complexes with histamine and pyridoxamine ligands studied by the stopped-flow technique
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Redox reactions of the FAD-containing apoptosis-inducing factor (AIF) with quinoidal xenobiotics: A mechanistic study
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On designing minimax adjustable wideband fractional delay FIR filters using two-rate approach
PublikacjaZaprezentowano nowe rozwiązanie problemu projektowania numerycznie oszczędnego, przestrajalnego, szerokopasmowego filtru ułamkowo opóźniającego o skończonej odpowiedzi impulsowej (FIR) w strukturze Farrowa. Innowacja polega na zagregowaniu dwóch podejść. Pierwsze z nich polega na równoczesnej optymalizacji wszystkich podfiltrów struktury Farrowa. Drugie wykorzystuje dwuszybkościową aranżację dwustopniową. Docelowe rozwiązanie jest...
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Reactions of solute species at an electrode modified with titanocene functionalized polypyrrole film: ferrocene and titanocene dichloride
PublikacjaPo raz pierwszy zbadano możliwość intermediacji ładunku poprzez centra tytanocenowe polimeru modyfikowanego chemicznie związanymi grupami dichloro tytanocenowymido polipirolu. Badano reakcje elektrodowe ferrocenu i dichlorotytanocenu. Wykazano aktywność elektrodową w zakresie potencjałów redoks pary Ti(IV/TiIII)w stosunku do reakcji redoks ferrocenu i reakcji dichlorotytanocenu. Wykazano, że centra TcCl2 polimeru są zadowalająco...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublikacjaThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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ORF Approximation in Numerical Analysis of Fractional Point Kinetics and Heat Exchange Model of Nuclear Reactor
PublikacjaThis paper presents results concerning numerical solutions of the fractional point kinetics (FPK) and heat exchange (HE) model for a nuclear reactor. The model consists of a nonlinear system of fractional and ordinary differential equations. Two methods to solve the model are compared. The first one applies Oustaloup Recursive Filter (ORF) and the second one applies Refined Oustaloup Recursive Filter (RORF). Simulation tests have...
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Linear-scaling calculation of Hartree-Fock exchange energy with Non-orthogonal Generalised Wannier Functions
PublikacjaWe present a method for the calculation of four-centre two-electron repulsion integrals in terms of localised non-orthogonal generalised Wannier functions (NGWFs). Our method has been imple- mented in the ONETEP program and is used to compute the Hartree-Fock exchange energy component of Hartree-Fock and Density Functional Theory (DFT) calculations with hybrid exchange-correlation functionals. As the NGWFs are optimised in situ...
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Influence of chloroform on crystalline products yielded in reactions of 5,10,15,20-tetraphenylporphyrin with HCl and copper(II) salts
PublikacjaStwierdzono, że chloroform wbudowuje się do sieci krystalicznej dichlorowodorku 5,10,15,20-tetrafenyloporfiryny, oraz że powoduje krystalizację nowej, jednoskośnej odmiany polimorficznej porfirynianu miedzi(II), CuTPP. W pracy opisano strukturę krystaliczną solwatu dichlorowodorku porfiryny z ośmioma cząsteczkami chloroformu, C44H32N42+·2Cl-·8CHCl3, i porównano ją...
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An investigation on the chemistry of the R2P=P ligand: reactions of a phosphanylphosphinidene complex of tungsten(VI) with electrophilic reagents
PublikacjaThe nucleophilic properties of the title compound [(2,6-i-Pr2C6H3N)2(Cl)W(η2-t-Bu2PvP)]Li·3DME (1) were investigated in reactions with selected electrophilic reagents such as MeI, M(CO)5THF (M = Cr, Mo, W), AlCl3, and GaCl3. Methylation of 1 by MeI yields phosphanylphosphido complexes [(2,6-i-Pr2C6H3N)2W(X)(1,2-η-t-Bu2PvP–CH3)] (X = Cl, I) (2-Cl/2-I) with the formation of a new P–C bond. Moreover, 1 reacts with electrophilic compounds...
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Comments on various extensions of the Riemann–Liouville fractional derivatives : About the Leibniz and chain rule properties
PublikacjaStarting from the Riemann–Liouville derivative, many authors have built their own notion of fractional derivative in order to avoid some classical difficulties like a non zero derivative for a constant function or a rather complicated analogue of the Leibniz relation. Discussing in full generality the existence of such operator over continuous functions, we derive some obstruction Lemma which can be used to prove the triviality...
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Modelling of residential sales price with kriging using different distance metrics in different correlation functions
PublikacjaThe modelling and estimation of sales prices based on economical conditions are important for housing sector especially in developing countries. Analysts are focused on the subject to analyze price movements and estimate the future trend of the sales prices for housing sector. In this study, we tried to generate a robust and efficient model related to the subject. Firstly, we investigated economic variables affecting housing sales...
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MEMORY EFFECT ANALYSIS USING PIECEWISE CUBIC B-SPLINE OF TIME FRACTIONAL DIFFUSION EQUATION
PublikacjaThe purpose of this work is to study the memory effect analysis of Caputo–Fabrizio time fractional diffusion equation by means of cubic B-spline functions. The Caputo–Fabrizio interpretation of fractional derivative involves a non-singular kernel that permits to describe some class of material heterogeneities and the effect of memory more effectively. The proposed numerical technique relies on finite difference approach and cubic...
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Variational principles for bound states of Schrödinger and Dirac equations allowing the use of discontinuous trial functions
PublikacjaWe present systematic constructions of variational principles for energies of bound states of the Schroedinger and Dirac equations. The principles allow the use of discontinuous trial functions. The method employed is based on a generalized Lagrange procedure. Relationships between our variational principles and those available in the literature are established.
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Cross-linking of polymer films using phenol-formaldehyde resins with different functional groups
PublikacjaWell-know phenol-formaldehyde resins are used in the production of press-materials, glues, protective coating, mastics. They take a special place among known oligomers because the products based on them are characterized by a low cost and a series of positive properties. Aim of the work: to show the possibility to create polymeric films based on epoxy resins and modified phenol-formaldehyde resins, which contain unsaturated double...
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Multivariate statistical comparison of analytical procedures for benzene and phenol determination with respect to their environmental impact
PublikacjaThe studydescribesthepossibilityofapplicationofself-organizingmapstechniquetoassessthe greenness ofanalyticalmethodologies.Themetrologicaland “environmentalimpact” parametersof proceduresforbenzeneandphenoldeterminationinwatersamplesweresetsofinputdatafor chemometric analysis.Totally47objectsand8variablesformedthedatausedforanalysis.Themajor factors responsiblefornon-greencharacterofthemethodologyaretheamountoforganicsolventand amount...
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Valence and lowest Rydberg electronic states of phenol investigated by synchrotron radiation and theoretical methods
PublikacjaWe present the experimental high-resolution vacuum ultraviolet (VUV) photoabsorption spectra of phenol covering for the first time the full 4.3–10.8 eV energy-range, with absolute cross sections determined. Theoretical calculations on the vertical excitation energies and oscillator strengths were performed using time-dependent density functional theory and the equation-of-motion coupled cluster method restricted to single and double...
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Actions of a nitric oxide donor on prostaglandin production and angiogenic activity in the equine endometrium
PublikacjaNitric oxide (NO) plays an important role in prostaglandin secretion and angiogenesis in the reproductive system. In the present study, the roles of the NO donor spermine NONOate and tumour necrosis factor-alpha (TNF; as a positive control) in prostaglandin production and angiogenic activity of equine endometria during the oestrous cycle were evaluated. In addition, the correlation between NO production...
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Antibody reactivity in patients with IgE-mediated wheat allergy to various subunits and fractions of gluten and non-gluten proteins from ω-gliadin-free wheat genotypes
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Profile and Content of Phenolic Compounds in Leaves, Flowers, Roots, and Stalks of Sanguisorba officinalis L. Determined with the LC-DAD-ESI-QTOF-MS/MS Analysis and Their In Vitro Antioxidant, Antidiabetic, Antiproliferative Potency
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Efficient optimization approaches for microwave assisted extraction of high-quality antioxidant compounds from Salvia officinalis L.: UHPLC-HRMS differential analysis of phenolic profiles obtained by ultrasound and microwave extraction
PublikacjaThe study aims to optimize MAE of total phenolic compounds (TPC) and antioxidant capacity from Salvia officinalis L. leaves using a definitive screening design (DSD) and I-optimal design. UHPLC-HRMS analysis was used to identify and compare the composition of MAE and UAE optimal extracts. The results showed that DSD and I-optimal design were successfully applied for the optimization of MAE targeting phenolics and other antioxidants...
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First-Phase Left Ventricular Ejection Fraction as an Early Sign of Left Ventricular Dysfunction in Patients with Stable Coronary Artery Disease
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