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Noncentrosymmetric superconductor with a bulk three-dimensional Dirac cone gapped by strong spin-orbit coupling
PublikacjaThe layered, noncentrosymmetric heavy element PbTaSe2 is found to be superconducting. We report its electronic properties accompanied by electronic-structure calculations. Specific heat, electrical resistivity, and magnetic-susceptibility measurements indicate that PbTaSe2 is a moderately coupled, type-IIBCSsuperconductor (Tc = 3.72 K, Ginzburg–Landau parameter κ = 17) with an electron-phonon coupling constant of λep = 0.74. Electronic-structure...
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A commercial gas boiler fitted with the ORC module as perspective solution for households
PublikacjaIn this paper the applicability of the commercial gas boiler (De Dietrich DTG X23N) coupled with the laboratory prototype micro ORC setup was experimentally studied. The main objective was to determine the working fluid capability to obtain required temperatures of vapour prior to the turbine, attainable heat rates and efficiencies of the whole system. The boiler thermal power was 25 kW. Tests were carried out with a single stage...
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COMPARISON OF INFINITE ELEMENT MODELS
PublikacjaThe main objective of this paper is to show the comparison of two models of infinite ab- sorbing layer with increasing damping in numerical investigations of elastic wave prop- agation in unbounded structures. This has been achieved by the Authors by a careful in- vestigation of two different engineering structures characterised by gradually increasing geometrical and mathematical description complexities. The analysis included...
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Low energy electron attachment to platinum(II) bromide (PtBr2)
PublikacjatDissociative electron attachment to PtBr2in the gas phase was studied in the low electron energy rangefrom zero up to 10 eV with an energy resolution of 150 meV. The experiments were carried out using ahemispherical electron monochromator coupled with a quadrupole mass spectrometer and pulse count-ing acquisition system. The only anion observed was Br−. This ion is formed at three resonance electronenergies: 0.4 eV, 1.2 eV and...
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Quechers sample preparation method variants for analysis of pesticide residues in fruits and vegetables
PublikacjaThis article describes the comparison of different versions of an easy, rapid and low-cost sample preparation approach for the determination of pesticide residues in fruits and vegetables by concurrent use of gas and liquid chromatography coupled to MS or ECD for detection. The sample preparation approach is known as QuEChERS, which stands for quick, easy, cheap, effective, rugged and safe. It is a combination of liquid-liquid...
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Principles of smoking
PublikacjaTreatment of a large variety of foods with wood smoke has been practiced for centuries—predominantlymeats, poultry, and fish, but also scallops, cheeses, prunes, paprika, and themalt used to produce whiskey and some sorts of beer.The process usually includes salting and partial drying; it may also be coupled with heating. The aim is to increase the shelf life of the products, prevent food poisoning, and add a desirable smoky flavor....
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Domestic ORC micro-CHP combined with a commercial gas boiler
PublikacjaThe chapter presents the results of experimental studies conducted during the launch of the first in Poland demonstration prototype of the micro ORC coupled to a domestic gas boiler. The accomplished studies indicated the possibility for the ORC module to work with such boiler (autonomous source of heat) with a prototype single-stage axial micro turbine as the expansion machine. Confirmation of that fact has been delineated in...
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System information propagation for composite structures
PublikacjaWe study in details decoherence process of a spin register, coupled to a spin environment. We use recently developed methods of information transfer study in open quantum systems to analyze information flow between the register and its environment. We show that there are regimes when not only the register decoheres effectively to a classical bit string, but this bit string is redundantly encoded in the environment, making it available...
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Determination of terpene profiles in potential superfruits
PublikacjaThe aim of this work was to characterize and compare the profiles of volatile terpenes in four potential superfruits. These profiles were determined using headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography linked to time-of-flight mass spectrometry. The proposed technique allowed the separation and identification of 79 terpenes present in cape gooseberry, crabapple, cherry silver...
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A DISCRETE-CONTINUOUS METHOD OF MECHANICAL SYSTEM MODELLING
PublikacjaThe paper describes a discrete-continuous method of dynamic system modelling. The presented approach is hybrid in its nature, as it combines the advantages of spatial discretization methods with those of continuous system modelling methods. In the proposed method, a three-dimensional system is discretised in two directions only, with the third direction remaining continuous. The thus obtained discrete-continuous model is described...
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Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter
PublikacjaA promising solution for inductive power transfer and wireless charging is presented on the basis of a single-phase three-level T-type Neutral Point Clamped GaN-based inverter with two coupled transmitting coils. The article focuses on the feasibility study of GaN transistor application in the wireless power transfer system based on the T-type inverter on the primary side. An analysis of power losses in the main components of the...
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ZnO ALD-Coated Microsphere-Based Sensors for Temperature Measurements
PublikacjaIn this paper, the application of a microsphere-based fiber-optic sensor with a 200 nm zinc oxide (ZnO) coating, deposited by the Atomic Layer Deposition (ALD) method, for temperature measurements between 100 and 300°C, is presented. The main advantage of integrating a fiber-optic microsphere with a sensing device is the possibility of monitoring the integrity of the sensor head in real-time, which allows for higher accuracy during...
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Recent Developments in Data-Assisted Modeling of Flexible Proteins
PublikacjaMany proteins can fold into well-defined conformations. However, intrinsically-disordered proteins (IDPs) do not possess a defined structure. Moreover, folded multi-domain proteins often digress into alternative conformations. Collectively, the conformational dynamics enables these proteins to fulfill specific functions. Thus, most experimental observables are averaged over the conformations that constitute an ensemble. In this...
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Inline Microstrip Bandpass Filter With Two Transmission Zeros and Increased Order Using Spurious Resonance of Frequency-Dependent Inverter
PublikacjaA design method for a class of fourth-order inline microstrip bandpass filter with two transmission zeros and 20% fractional bandwidth is presented. The filter consists of two quarter-wavelength transmission-line resonators coupled by a frequency-dependent inverter. The inverter is composed of two open-ended stubs that are connected by an interdigital capacitor and introduces two poles and two transmission zeros in the filter response....
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Superconductivity in the superhard boride WB4.2
PublikacjaWe show that the superhard boride WB4.2 is a superconductor with a Tc of 2.05(5) K. Temperature-dependent magnetic susceptibility, electrical resistivity, and specific heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ for WB4.2 is 2.07(3) mJ mol−1 K−2 and the ΔC/γTc=1.56, which is somewhat higher than what is expected for weakly coupled Bardeen–Cooper–Schrieffer type superconductors....
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Towards Knowledge Formalization and Sharing in a Cognitive Vision Platform for Hazard Control (CVP-HC)
PublikacjaHazards are present in all workplaces and can result in serious injuries, short and long-term illnesses, or death. In this context, management of safety is essential to ensure the occupational health of workers. Aiming to assist the safety manage-ment process, especially in industrial environments, a Cognitive Vision Platform for Hazard Control (CVP-HC) has been proposed. The CVP-HC is a scalable yet adaptable system capable of...
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On Radar DoA Estimation and Tilted Rotating Electronically Scanned Arrays
PublikacjaWe consider DoA estimation in a monopulse radar system employing a tilted rotating array. We investigate the case of nonzero steering angles, in which case the mapping between the target’s azimuth and elevation in the global coordinate system and their counterparts in the array local coordinate system becomes increasingly nonlinear and coupled. Since estimating the azimuth using coherently integrated signals might be difficult because...
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Pursuing Listeners’ Perceptual Response in Audio-Visual Interactions - Headphones vs Loudspeakers: A Case Study
PublikacjaThis study investigates listeners’ perceptual responses in audio-visual interactions concerning binaural spatial audio. Audio stimuli are coupled with or without visual cues to the listeners. The subjective test participants are tasked to indicate the direction of the incoming sound while listening to the audio stimulus via loudspeakers or headphones with the head-related transfer function (HRTF) plugin. First, the methodology...
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Criteria for assessment of pine wood surfaces after planing
PublikacjaThe arise of defects in raw material as well as a machined part in most cases causes need to qualify the final product (wooden frames) as a scrap part or an additional work activity must be done. In the paper selected results of the effect of the material defects on the surface quality of the elements after planing and painting are presented. The materials under production were glulam elements of pine wood. Research experiments...
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On time-dependent nonlinear dynamic response of micro-elastic solids
PublikacjaA new approach to the mechanical response of micro-mechanic problems is presented using the modified couple stress theory. This model captured micro-turns due to micro-particles' rotations which could be essential for microstructural materials and/or at small scales. In a micro media based on the small rotations, sub-particles can also turn except the whole domain rotation. However, this framework is competent for a static medium....
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Optical and structural properties of polycrystalline CVD diamond films grown on fused silica optical fibres pre-treated by high-power sonication seeding
PublikacjaIn this paper, the growth of polycrystalline chemical vapour deposition (CVD) diamond thin films on fused silica optical fibres has been investigated. The research results show that the effective substrate seeding process can lower defect nucleation, and it simultaneously increases surface encapsulation. However, the growth process on glass requires high seeding density. The effects of suspension type and ultrasonic power were...
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Electrical characterization of diamond/boron doped diamond nanostructures for use in harsh environment applications
PublikacjaThe polycrystalline boron doped diamond (BDD) shows stable electrical properties and high tolerance for harsh environments (e.g. high temperature or aggressive chemical compounds) comparing to other materials used in semiconductor devices. In this study authors have designed electronic devices fabricated from non-intentionally (NiD) films and highly boron doped diamond structures. Presented semiconductor devices consist of highly...
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Fabrication and characterization of boron-doped nanocrystalline diamond-coated MEMS probes
PublikacjaFabrication processes of thin boron-doped nanocrystalline diamond (B-NCD) films on silicon-based micro- and nano-electromechanical structures have been investigated. Nanocrystalline boron doped -diamond (B-NCD) films were deposited using Microwave Plasma Assisted Chemical Vapour Deposition (MW PA CVD) method. The variation of B-NCD morphology, structure and optical parameters were particularly investigated. The use of truncated...
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Electrochemically assisted deposition of hydroxyapatite on Ti6Al4V substrates covered by CVD diamond films — Coating characterization and first cell biological results
PublikacjaAlthough titaniumand its alloys are widely used as implant material for orthopedic and dental applications they show only limited corrosion stability and osseointegration in different cases. The aim of the presented research was to develop and characterize a novel surface modification system from a thin diamond base layer and a hydroxyapatite (HAp) top coating deposited on the alloy Ti6Al4V widely used for implants in contact with bone....
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Recent advances in high-frequency modeling by means of domain confinement and nested kriging
PublikacjaDevelopment of modern high-frequency components and circuits is heavily based on full-wave electromagnetic (EM) simulation tools. Some phenomena, although important from the point of view of the system performance, e.g., EM cross-coupling effects, feed radiation in antenna arrays, substrate anisotropy, cannot be adequately accounted for using simpler means such as equivalent network representations. Consequently, the involvement...
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Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films
PublikacjaBoron doped diamond (BDD) has great potential in electrical, and electrochemical sensing applications. The growth parameters, substrates, and synthesis method play a vital role in the preparation of semiconducting BDD to metallic BDD. Doping of other elements along with boron (B) into diamond demonstrated improved efficacy of B doping and exceptional properties. In the present study, B and nitrogen (N) co-doped diamond has been...
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TR-Based Antenna Design with Forward FD: The Effects of Step Size on the Optimization Performance
PublikacjaNumerical methods are important tools for design of modern antennas. Trust-region (TR) methods coupled with data-efficient surrogates based on finite differentiation (FD) represent a popular class of antenna design algorithms. However, TR performance is subject to FD setup, which is normally determined a priori based on rules-of-thumb. In this work, the effect of FD perturbations on the performance of TR-based design is evaluated...
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Validation of atmospheric aerosols sampling in equivalent fractions
PublikacjaPhysical properties and chemical composition of atmospheric aerosols are of extreme importance, in many fields of interest, namely the Environment even with legal implications. Atmospheric sampling poses inherent problems with consequent demands on sampling optimisation, with sampling strategies requiring validation. In this work a study was conducted aiming at validating the collection of atmospheric aerosols in equivalent fractions....
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Environmental Fate of Two Psychiatric Drugs, Diazepam and Sertraline: Phototransformation and Investigation of their Photoproducts in Natural Waters
PublikacjaExperimental studies were conducted to investigate the photodegradation of diazepam and sertraline, two of the most frequently used psychiatric drugs, induced by xenon lamp irradiation, which overlap the sunlight spectra, and natural sunlight. Degradation kinetics was established indicating the occurrence of autocatalytic reactions. The application of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry...
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Fast bubble dynamics and sizing
PublikacjaSingle bubble sizing is usually performed by measuring the resonant bubble response using the Dual Frequency Ultrasound Method. However, in practice, the use of millisecond-duration chirp-like waves yields nonlinear distortions of the bubble oscillations. In comparison with the resonant curve obtained under harmonic excitation, it was observed that the bubble dynamic response shifted by up to 20 percent of the resonant frequency...
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The Current State-of-the-Art in the Determination of Pharmaceutical Residues in Environmental Matrices Using Hyphenated Techniques
PublikacjaSeveral thousand tons of pharmaceuticals and their transformation products (metabolites and degradation products) are introduced into the environment each year. They affect both human health and the environment, therefore, analytical procedures enabling the determination of a wide range of pharmaceuticals at trace levelswithminimal effort, time, and energy are required. Nowadays, hyphenated techniques are commonly applied in pharmaceutical...
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Effects of subfilter velocity modelling on dispersed phase in LES of heated channel flow
PublikacjaA non-isothermal turbulent flow with the dispersed phase is modelled using the Large Eddy Simulation (LES) approach for fluid, one-way coupled with the equations of point-particle evolution. The channel is heated at both walls and isoflux boundary conditions are applied for fluid. Particle velocity and thermal statistics are computed. Of particular interest are the r.m.s. profiles and the probability density function of particle...
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Analysis of arsenic species in environmental samples
PublikacjaMany analytical methods for determining arsenic in various forms in environmental samples have been developed in recent years. The main objective of this review article is the presentation and comparison of the three principal techniques for the determination arsenic compounds, namely: hydride generation (HG), voltammetry and chromatography (liquid chromatography including high-performance liquid chromatography (HPLC), and gas...
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Detection of apple in orange juice using ultra-fast gas chromatography
PublikacjaThe determination of authenticity is an increasingly important issue for food quality and safety. The use of an electronic nose based on ultra-fast gas chromatography technique ensures rapid analysis of the volatile compounds from food products. Due to the fact that this technique enables chemical profiling of agricultural products, it can be an effective tool for authentication when combined with chemometrics. In this article...
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Finite element/mode-matching analysis of ferrite/dielectric line junctions of arbitrary cross-section
PublikacjaThis paper is focused on the analysis of line junctions obtained as a cascade of dielectric and ferrite guides of arbitrary cross-section. The main application of such structures is nonreciprocal devices such as isolators, circulators, or phase shifters. The efficient finite element/mode-matching approach is proposed to the analysis of such structures. In this approach, thefiniteelementmethod is applied todetermine propagation...
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Advances in mass spectrometry for iron speciation in plants
PublikacjaIron is an important nutrient essential for plants and critical for human health. The state-of-the art of methods for iron speciation in cereal grains and plant fluids is critically reviewed. Particular attention is given to the latest developments in the coupling of HPLC with the parallel ICP MS and electrospray ionization (ESI) MS/MS detection, usually QTOF MS or Q-Orbitrap MS, for the identification and quantification of iron...
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Thermal degradation kinetics of poly(propylene succinate) prepared with the use of natural origin monomers
PublikacjaLinear biobased polyester polyols were prepared with the use of succinic acid and 1,3-pro- panediol (both with natural origin). Tetraisopropyl orthotitanate (TPT) was used as a catalyst. In order to determine the effect of various synthesis temperature conditions on the thermal degradation kinet- ics, nine sequences of temperature conditions were used during two-step polycondensation reaction. Thermogravimetric analysis was conducted...
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Theoretical study of the structure, energetics and vibrational frequencies of water-acetone and water-2-butanone complexes
PublikacjaKompleksy 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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LDFEM analysis of FDP auger installation in cohesive soil
PublikacjaThis paper deals with large deformation finite element (LDFE) preliminary modelling of Full Displacement Pile (FDP) installation in cohesive soil deposit located in Jazowa, Poland. The detailed FDP auger geometry is applied and the drilling process is modelled with full 3D Coupled Eulerian-Lagrangian (CEL) formulation. The total stress approach and elastic-perfectly plastic model with rate-dependent Mises plasticity is used. The...
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A non-adiabatic wavepacket dynamical study of the low energy chargetransfer process in the S3+ + H collision
PublikacjaThe collisional system S3+ + H?S2+ + H+ has been studied using a time-dependent wavepacket methodologyin two-dimensions. Using available potential energy surfaces and coupling matrix elementsobtained from multireference ab initio calculations, five non-adiabatically coupled electronic states of1P symmetry have been included in the dynamical simulations. The collision has been studied in thelow energy regime of 1-10 eV. The wavepacket...
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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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A Wind Energy Conversion System Based on a Generator with Modulated Magnetic Flux
PublikacjaIn this work, the concept of an energy conversion system for wind turbines based on the modified permanent magnet synchronous generator (PMSG) is presented. In the generator, a pair of three-phase windings is used, one of which is connected in a “star” and the second in a “delta” configuration. At the outputs of both windings, two six-pulse uncontrolled (diode) rectifiers are included. These rectifiers are mutually coupled by a...
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Nonreciprocal cavities and the time-bandwidth limit: comment
PublikacjaIn their paper in Optica 6, 104 (2019), Mann et al. claim that linear, time-invariant nonreciprocal structures cannot overcome the time-bandwidth limit and do not exhibit an advantage over their reciprocal counterparts, specifically with regard to their time-bandwidth performance. In this Comment, we argue that these conclusions are unfounded. On the basis of both rigorous full-wave simulations and insightful physical justifications,...
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Preparation and characterisation of iron substituted Mn1.7Cu1.3-xFexO4 spinel oxides (x = 0, 0.1, 0.3, 0.5)
PublikacjaSpinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical...
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Effect of Axial Porosities on Flexomagnetic Response of In-Plane Compressed Piezomagnetic Nanobeams
PublikacjaWe investigated the stability of an axially loaded Euler–Bernoulli porous nanobeam considering the flexomagnetic material properties. The flexomagneticity relates to the magnetization with strain gradients. Here we assume both piezomagnetic and flexomagnetic phenomena are coupled simultaneously with elastic relations in an inverse magnetization. Similar to flexoelectricity, the flexomagneticity is a size-dependent property. Therefore,...
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Strong-coupling superconductivity of SrIr2 and SrRh2 : Phonon engineering of metallic Ir and Rh
PublikacjaExperimental and theoretical studies on superconductivity in SrIr2 and SrRh2 Laves phases are presented. The measured resistivity, heat capacity, and magnetic susceptibility confirm the superconductivity of these compounds with Tc = 6.07 and 5.41 K, respectively. Electronic structure calculations show that the Fermi surface is mostly contributed by 5d (4d) electrons of Ir (Rh), with Sr atoms playing the role of electron donors....
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Charge density wave and large nonsaturating magnetoresistance in YNiC2 and LuNiC2
PublikacjaWe report a study of physical properties of two quasi-low-dimensional metals YNiC2 and LuNiC2 including the investigation of transport, magnetotransport, galvanomagnetic, and specific heat properties. In YNiC2 we reveal two subsequent transitions associated with the formation of weakly coupled charge density wave at TCDW=318K and its locking in with the lattice at T1=275K. These characteristic temperatures follow the previously...
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Mathematical modeling of hydrogen production performance in thermocatalytic reactor based on the intermetallic phase of Ni3Al
PublikacjaThe main goal of the following work is to adjust mathematical modelling for mass transfer, to specific conditions resulting from presence of chemical surface reactions in the flow of the mixture consisting of helium and methanol. The thermocatalytic devices used for decomposition of organic compounds incorporate microchannels coupled at the ends and heated to 500 oC at the walls regions. The results of the experiment were compared...
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublikacjaIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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High Efficiency Dual-Active-Bridge Converter with Triple-Phase-Shift Control for Battery Charger of Electric Vehicles
PublikacjaAn optimal modulation scheme with triple-phase-shift (TPS) control could increase the efficiency in the entire load range for a dual-active-bridge (DAB) converter under wide output voltage range conditions. Therefore, this study proposes a convergent approach to TPS mode selection, coupled with an optimal modulation scheme, ensuring the circuit’s efficiency over the entire range in the realm of a high-power and high-efficiency...