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Theoretical study of the photoelectron spectrum of ethyl formate: Ab initio and density functional theory investigation
PublicationThe first ionization energy and associated photoelectron spectrum of ethyl formate are investigated with quantum chemistry calculations. The geometries, harmonic vibrational frequencies and first ionization energy are computed at the Hartree-Fock (HF) and at the second order Moller-Plesset perturbation theory (MP2). Moreover, accurate ionization energies are obtained with the Coupled-Cluster theory including singles and doubles...
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Polystyrene/polybutadiene blends: An analysis of the phase-inversion region and cophase continuity and a comparison with theoretical predictions
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Polystyrene/polybutadiene blends: An analysis of the phase-inversion region and cophase continuity and a comparison with theoretical predictions
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Theoretical Investigation of the Electron-Transfer Dynamics and Photodegradation Pathways in a Hydrogen-Evolving Ruthenium-Palladium Photocatalyst
PublicationTime-dependent density functional theory calcula- tions combinedwith the Marcus theory of electron transfer (ET) were app lied on the molecular photocatalys t [(tbbpy) 2 Ru(tpph z)PdC l 2 ] 2 + in order to elucidate thelight-in- duced relaxation pathways populated upon excitation in the longer wavelength range of its absorption spectrum. The computational resultsshow that after the initial excitation, metal (Ru) to ligand (tpphz)chargetransfer...
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WATER LUBRICATED MAIN SHAFT BEARINGS - MODERN SOLUTION FOR HYDROPOWER INDUSTRY - Experimental and theoretical studies
PublicationWater-lubricated bearings are finding increasingly wide use in various branches of industry. As such, they may also be encountered in hydro power industry. They are also increasingly frequently employed in bearing systems of marine shaft propulsions and water pumps [1]. This rising popularity is due to a number of reasons [2]. First of all, their simple construction has direct impact on the level of pricing which is usually quite...
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Experimental and Theoretical Investigations of the Stability of Two Small Gaseous Dicarboxylate Dianions: Acetylene Dicarboxylate and Succinate
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On the critical temperature discontinuity at the theoretical bcc-fcc phase transition in compressed selenium and tellurium superconductors
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Polystyrene/polybutadiene blends: an analysis of the phase inversion regionand cophase continuity and a comparison with theoretical predictions.
PublicationMieszaniny przygotowano przez mieszanie w stopie. Występowanie jednego lubobu polimerów w postaci fazy ciągłej stwierdzano przez badanie morfologii przy pomocy skaningowego mikroskopu elektronowego i przez rozpuszczanie jednego ze składników mieszaniny. Badania morfologii mieszanin wykazały, że polistyren występował w postaci globul przy jego zawartości do 30%. Przy zawartości od 40% do 60% obserwowano fazy ciągłe obu...
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Theoretical study of the structure, energetics and vibrational frequencies of water-acetone and water-2-butanone complexes
PublicationKompleksy acetonu i 2-butanonu z 0-2 cząsteczkami wody połączonymi wiązaniem wodorowym z tlenem karbonylowym zbadano z wykorzystaniem teorii funkcjonału gęstości (DFT) na poziomie B3LYP/6-311++G(d,p). Obliczenia w fazie gazowej uzupełniono o optymalizacje w otoczeniu rozpuszczalnika, symulowanego za pomocą modelu polaryzowalnego kontinuum (PCM). Częstości drgań oscylacyjnych otrzymane na podstawie zależności empirycznej sa zgodne...
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Experimental and theoretical studies of spectroscopic properties of simple symmetrically substituted diphenylbuta-1,3-diyne derivatives
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THE THEORETICAL STUDY ON INFLUENCE OF FUEL INJECTION PRESSURE ON COMBUSTION PARAMETERS OF THE MARINE 4-STROKE ENGINE
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Theoretical and experimental analysis of guided wave propagation in plate-like structures with sinusoidal thickness variations
PublicationGuided waves have attracted significant attention for non-destructive testing (NDT) and structural health monitoring (SHM) due to their ability to travel relatively long distances without significant energy loss combined with their sensitivity to even small defects. Therefore, they are commonly used in damage detection and localization applications. The main idea of incorporating guided waves in NDT and SHM is based on processing...
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Integrated Experimental and Theoretical Approach for Efficient Design and Synthesis of Gold-Based Double Halide Perovskites
PublicationApplied cutting-edge electronic structure and phonon simulations provide a reliable knowledge about the stability of perovskite structures and their electronic properties, which are crucial for design of effective nanomaterials. Gold is one of the exceptional elements, which can exist both as a monovalent and a trivalent ion in the B site of a double perovskite such as A2BI BIIIX6. However, until now, electronic properties of Cs2AuI AuIIIX6...
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Theoretical calculation of the physico-chemical properties of 1-butyl-4-methylpyridinium based ionic liquids
PublicationACCEPTED MAIonic liquids (ILs) have attracted much attention for their unique physicochemical properties, which can be designed as needed by altering the ion combinations. Besides experimental work, numerous computational studies have been concerned with prediction of physical properties of ILs. The results of molecular dynamics simulations of ILs depend strongly on the proper force field parameterization. Classical force fields...
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Theoretical investigation of the structural insights of the interactions of γ-Fe2O3 nanoparticle with (EMIM TFSI) ionic liquid
PublicationOne of the possible applications of ionic liquids is to produce electricity from heat. The iron oxide nanoparticle is a potent electrical particle, which is expected to improve the heat’s efficiency to electricity conversion, however, it is prone to aggregation and sedimentation, which hamper its application. One of the methods to enhance the nanoparticle’s solubility and electrical properties is the use of a stabilizing component...
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Theoretical and Actual Feed Per Tooth During Wood Sawing on an Optimizing Cross-Cut Saw
PublicationThe work presents the geometries of circular saw teeth, whose task is to divide the cross-cut of the cutting layer. For efficient machining on a cross-cut saw with high feed speed values (about 1 ms−1) maximal theoretical feeds per tooth are determined. These values were compared with the actual values determined during transverse cutting of pine wood on a special test stands in industrial conditions. In the experiment the rotational...
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Theoretical and Experimental Studies on the Visible Light Activity of TiO2 Modified with Halide-Based Ionic Liquids
PublicationFormation of a surface complex between organic molecules and TiO2 is one of the possible strategies for the development of visible light-induced TiO2 photoactivity. Herein, three ionic liquids (ILs) with the same cation and dierent anions (1-butylpirydynium chloride/bromide/iodide) have been applied for the surface modification of TiO2 and to understand the role of anions in visible light-induced activity of ILs-TiO2 systems. Photocatalytic...
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An intelligent cellular automaton scheme for modelling forest fires
PublicationForest fires have devastating consequences for the environment, the economy and human lives. Understanding their dynamics is therefore crucial for planning the resources allocated to combat them effectively. In a world where the incidence of such phenomena is increasing every year, the demand for efficient and accurate computational models is becoming increasingly necessary. In this study, we perform a revision of an initial proposal...
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Hydraulic equations for vortex separators dimensioning
PublicationThe paper presents a set of hydraulic expressions developed to design vortex separators. These devices are used for gravitational removal of suspensions from wastewater. Measurements and theoretical considerations allowed the authors to formulate a mathematically simple velocity field model. Than, equations describing particle motion in the separator were derived. Finally, a technical procedure for hydraulic design of vortex separators...
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Laboratory Load Model Based on 150 kVA Power Frequency Converter and Simulink Real-Time – Concept, mplementation, Experiments
PublicationFirst section of the paper provides technical specification of laboratory load model basing on 150 kVA power frequency converter and Simulink Real-Time platform. Assumptions, as well as control algorithm structure is presented. Theoretical considerations based on criteria which load types may be simulated using discussed laboratory setup, are described. As described model contains transformer with thyristor-controlled tap changer,...
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The CFD analysis of influence the start of fuel injection (SOI) on combustion parameters and exhaust gas composition of the marine 4-stroke engine
PublicationThe paper presents a theoretical analysis of the impact of injection timing on the parameters of the combustion process and the composition of exhaust gas from a 4-stroke engine designed to shipbuilding. The analysis was carried out based on a three-dimensional multi-zone model of the combustion process. This model has been prepared on the basis of properties of the research facility. The input data to the model were obtained through...
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Numerical simulation of hardening of concrete plate
PublicationThe paper presents a theoretical formulation of concrete curing in order to predict temperature evolution and strength development. The model of heat flow is based on a well-known Fourier equation. The numerical solution is implemented by means of the Finite Difference Method. In order to verify the model, the in situ temperature measurements at the top plate of a road bridge were carried out. A high agreement between numerical...
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The power of silence? opinion contagion and the surprise of the polish 2005 parlamentary and presidential elections
PublicationThis paper investigates opinion contagion in collective behaviour using threshold model (Granovetter (1978), Krassa(1988)). The theoretical background is the spiral of silence concept developed by Noelle-Neumann (1974), arguing that people only assert their opinions if they perceive a minimal support from a relevant proportion of others. We apply the model to explain the dispersion between pre-elections preferences and the final...
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Electronically Excited States in Solution via a Smooth Dielectric Model Combined with Equation-of-Motion Coupled Cluster Theory
PublicationWe present a method for computing excitation energies for molecules in solvent, based on the combination of a minimal parameter implicit solvent model and the equation-of-motion coupled-cluster singles and doubles method (EOM-CCSD). In this method, the solvent medium is represented by a smoothly varying dielectric function, constructed directly from the quantum mechanical electronic density using only two tunable parameters. The...
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Empirical verification in industrial conditions of fracture mechanics models of cutting power prediction
PublicationA comparison of experimental results obtained in the industrial conditions at a sawmill located in the Baltic Natural Forest Region (PL) and theoretical cutting power consumption forecasted with the models which include work of separation (fracture toughness) in addition to plasticity and friction has been described. In computations of cutting power consumption during rip sawing of Scots pine wood (Pinus sylvestris L.) values of...
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Design and experimental validation of a single-stage PV string inverter with optimal number of interleaved buck-boost cells.
PublicationIncreasing converter power density is a problem of topical interest. This paper discusses an interleaved approach of the efficiency increase in the buck-boost stage of an inverter with unfolding circuit in terms of losses in semiconductors, output voltage ripples and power density. Main trends in the power converter development are reviewed. A losses model was designed and used for the proposed solution to find an optimal number...
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Migration of container terminals as their natural process of evolution: Case study of Gdańsk and Gdynia ports
PublicationThe paper proposes a theoretical model of container terminals and container port development, based on the life cycle theory, threshold theory and catastrophe theory, and in references to Kuznets' swings (interpreted as waves of infrastructural investments), and Kondratiev long economic waves. The aim of this model is to explain the development process of a container terminal and a port within one technological generation, as...
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Modelling study of flow boiling heat transfer of perspective fluids for refrigeration technology
PublicationThere is a gap of knowledge on flow boiling at high saturation temperatures and higher values of reduced pressure. Thus far, the in-house developed semi-empirical model for flow boiling and flow condensation showed a satisfactory accuracy for calculations for various refrigeration fluids for a wide scope of reduced pressures. This study presents results of calculations of heat transfer coefficient of perspective refrigeration fluids,...
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Accelerated Gradient-Based Optimization of Antenna Structures Using Multi-Fidelity Simulations and Convergence-Based Model Management Scheme
PublicationThe importance of numerical optimization has been steadily growing in the design of contemporary antenna structures. The primary reason is the increasing complexity of antenna topologies, [ a typically large number of adjustable parameters that have to be simultaneously tuned. Design closure is no longer possible using traditional methods, including theoretical models or supervised parameter sweeping. To ensure reliability, optimization...
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Comparison of predictive methods for flow boiling heat transfer in conventional channels and minichannels - the effect of reduced pressure
PublicationIn the paper are presented the results of follow on studies from [1]–[3] using authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data collected from various researchers to investigate the sensitivity of the in-house developed model. The collected experimental data came from various studies from literature and were conducted for the full...
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Experimental and theoretical studies on the photodegradation of 2-ethylhexyl 4-methoxycinnamate in the presence of reactive oxygen and chlorine species
Publication2-Ethylhexyl 4-methoxycinnamate (EHMC) is one of the most commonly used sunscreen ingredient. In this study we investigated photodegradation of EHMC in the presence of such common oxidizing and chlorinating systems as H2O2, H2O2/HCl, H2O2/UV, and H2O2/HCl/UV. Reaction products were detected by gas chromatography with a mass spectrometric detector (GC-MS). As a result of experimental studies chloro-substituted 4-methoxycinnamic...
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The electronic excited states of dichloromethane in the 5.8-10.8 eV energy range investigated by experimental and theoretical methods
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Synthesis, physicochemical and theoretical studies on new rhodium and ruthenium dimers. Relationship between structure and cytotoxic activity
PublicationTwo dimeric compounds of the general formulae (Et3NH)2[Rh2(μ2-L)4Cl2] (1) (where L = thiophene-2-carboxylate) and [((η6-p-cymene)Ru)2(μ-Cl)3]PF6 (2) have been synthesized using a new method. The unique anionic complex 1 (space group P bca) has octahedral coordination in which the equatorial positions are occupied by the oxygen atoms of four thiophene-2-carboxylates in a paddle wheel fashion. In complex 2 (space group ), each Ru(II)...
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Theoretical Design of the Molecular Structure of Bent-Core Mesogens with Large Second-Order Nonlinear Optical Properties
PublicationABSTRACT: The first hyperpolarizability of two series of moleculeswith bent-shaped structures has been calculated at the ab initio level.The two series consist of carboxyl derivatives for which somemolecules are known to exhibit banana phases and of their sulfinatehomologues that have not been synthesized yet. The final purpose isto reveal the relevance or not in synthesizing these latter molecules.The strategy is based on reporting...
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Experimental and theoretical analyses of the nonlinear optical effects in magnesium and copper co-doped zinc oxide nanorods
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Steroidal Molecular Rotors with 1,4-Diethynylphenylene Rotators: Experimental and Theoretical Investigations Toward Seeking Efficient Properties
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Two-body dissociation of isoxazole following double photoionization – an experimental PEPIPICO and theoretical DFT and MP2 study
PublicationThe dissociative double photoionization of isoxazole molecules has been investigated experimentally and theoretically. The experiment has been carried out in the 27.5–36 eV photon energy range using vacuum ultraviolet (VUV) synchrotron radiation excitation combined with ion time-of-flight (TOF) spectrometry and photoelectron–photoion–photoion coincidence (PEPIPICO) technique. Five wellresolved two-body dissociation channels have...
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Teoretyczny opis metody pomiaru chwilowego widma impedancyjnego. Theoretical description of the measuring of instantenous impedance spectra
PublicationPrzedstawiony został teoretyczny opis wyznaczania chwilowego widma impedancyjnego. Połączenie szumu pseudo-białego oraz metody krótkoczasowej transformacji Fouriera pozwala na wyznaczenie zmian widma impedancyjnego w funkcji czasu. Teoretyczne podstawy nowej metody pomiarowej wskazują na możliwość zastosowania jej do procesów niestacjonarnych.
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Sliding bearings with sintered bronze bush lubricated by contaminated water with solid particles – Theoretical and experimental studies
PublicationSliding journal bearings lubricated with water coming directly from the environment are a solution used in shipbuilding, pumps and hydropower. However, the working fluid or surrounding water cannot always be filtered because of design limitations, which often causes the problem of premature wear of these sensitive bearings. The research conducted made it possible to assess the wear of sliding bearings lubricated with water containing...
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Fourier transform infrared spectroscopic and theoretical study of water interactions with glycine and its N-methylated derivatives
PublicationZbadano hydratację glicyny i jej metylowych pochodnych: N-metyloglicyny (NMG), N,N-dimetyloglicyny (DMG) i N,N,N-trimetyloglicyny (TMG) przy wykorzystaniu spektroskopii FTIR, z zastosowaniem cząsteczki HDO jako sondy molekularnej. Ilościowa wersja metody widm różnicowych pozwoliła na wyizolowanie widma wody zaburzonej przez substancję rozpuszczoną. Wyniki widmowe zostały skonfrontowane z obliczeniami teoretycznymi w ramach teorii...
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Theoretical and experimental investigation of low-noise optoelectronic system configurations for low-coherent optical signal detection
PublicationW artykule przedstawiono wyniki teoretycznej i eksperymentalnej analizy konfiguracji niskokoherencyjnego układu detekcji sygnałów optycznych. Zaprezentowano zaprojektowany układ detekcji optycznych sygnałów niskokoherencyjnych, który pozwala na pracę w konfiguracji zrównoważonej i niezrównoważonej, co umożliwia porównanie parametrów obu konfiguracji.
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Self-advocacy of a person with a disability in the dual role of paid worker and volunteer: Theoretical considerations and a case study
PublicationThe changing models of disability influence the way people with disabilities participate in social life, and how they can transform their life and environment. Such participation may take the form of work and volunteering, as well as participation in self-advocacy movements. This paper aims to explore how a woman with hearing impairment perceives her dual role as a regular worker and voluntary self-advocate within one organization...
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The electronic excited states of dichloromethane in the 5.8-10.8 eV energy range investigated by experimental and theoretical methods
PublicationWe present a comprehensive experimental high-resolution vacuum ultraviolet (VUV) photoabsorption spectrum of dichloromethane, CH 2 Cl 2 , with absolute cross sections determined for the full 5.8–10.8 eV energy-range. The calculations on the vertical excitation energies and oscillator strengths were performed using the equation-of-motion coupled cluster method, restricted to the single and double excitations level (EOM-CCSD), and...
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Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions
PublicationAg-based plasmonic nanostructures were manufactured by thermal annealing of thin metallic films. Structure and morphology were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). SEM images show that the formation of nanostructures is influenced by the initial layer thickness as well as the...
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Site-to-site distance distribution in flexible molecules: theoretical evaluation of the donor and/or acceptor fluorescence decay function
PublicationPrzedstawiono wyrażenie teoretyczne opisujące zależność funkcji zaniku fluorescencji od rozkładu odległości P(r) pomiędzy donorami i akceptorami w giętkich molekułach dwuchromoforowych. Wyrażenie uwzględnia wiekoeksponencjalny zanik izolowanych donorów i akceptorów, a także możliwość niekompletnego oznakowania molekuł akceptorami. Przyjęto, że względne zmiany odległości donorów i akceptorów w czasie życia fluorescencji donora mogą...
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New Generation of Water lubricated Foil bearing - Numerical Models and Experimental Verification
PublicationIn the paper a new idea of foil water lubricated bearing and methodology of hydrodynamic characteristics calculations is presented. To assesses the theoretical characteristics of these bearings two different computer models were built. First is structural model coupled with fluid model. It takes into account: fluid flow in the deformed fluid gap, specific design of bearing support and friction in bearing support. The second is...
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Analytical Modelling of the Multicell Piezoelectric Motor Based on Three Resonance Actuators
PublicationThis paper presents analytical model of the multicell piezoelectric motor. The results, obtained in the field of piezoelectric motors, have pointed out that these motors have potentially high possibilities in the future of special applications. The studied multicell piezoelectric motor have a stator using three rotating mode actuators. A theoretical analysis of operating principle of the rotating mode motor has been described....
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Rethinking non-governmental organizations – at the crossroad of economics and civil society
PublicationThe article aims to close the existing knowledge gaps, show why non‑governmental organizations are founded and maintained, and elaborate and systematize the existing knowledge through an analysis of the existing subdisciplines within economics, laying the groundwork for the economics of non‑governmental organizations. The article was written based on a structured literature review with an approach similar to the grounded theory...
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Influence of Properties of Hydraulic Fluid on Pressure Peaks in Axial Piston Pumps’ Chambers
PublicationThe article concentrates on the research of the pressure peaks in a working chamber of an axial piston pump. The main focus of the article is the influence of fluid properties on the pressure peaks value. Experimental and analytical methods were used to determine the impact of the fluid density, viscosity, compressibility and aeration. The article describes the pressure peak generation process and explains the theoretical basis...
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Microstructure and Mechanical Properties of Carboxylated Nitrile Butadiene Rubber/Epoxy/XNBR-grafted Halloysite Nanotubes Nanocomposites
PublicationThe effect of various amounts of carboxylated nitrile butadiene rubber (XNBR) functionalized halloysite nanotubes (XHNTs) on the cure characteristics, mechanical and swelling behavior of XNBR/epoxy compounds was experimentally and theoretically investigated. The morphology of the prepared XNBR/epoxy/XHNTs nanocomposites was imaged using scanning electron microscopy (SEM). The effects of various XNBR-grafted nanotubes on the damping...