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Carbon nanowalls: A new versatile graphene based interface for laser desorption/ionization-mass spectrometry detection of small compounds in real samples.
PublikacjaCarbon nanowalls, vertically aligned graphene nanosheets, attract attention owing to their tunable band-gap, high conductivity, high mechanical robustness, high optical absorbance and other remarkable properties. In this paper, we report for the first time, the use of hydrophobic boron-doped carbon nanowalls (CNWs) for laser desorption/ionization of small compounds and their subsequent detection by mass spectrometry (LDI-MS). The...
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Open extensive IoT research and measurement infrastructure for remote collection and automatic analysis of environmental data.
PublikacjaInternet of Things devices that send small amounts of data do not need high bit rates as it is the range that is more crucial for them. The use of popular, unlicensed 2.4 GHz and 5 GHz bands is fairly legally enforced (transmission power above power limits cannot be increased). In addition, waves of this length are very diffiult to propagate under field conditions (e.g. in urban areas). The market response to these needs are the...
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An experimental EEG study of brain activities underlying the Autonomous Sensory Meridian Response
PublikacjaAutonomous Sensory Meridian Response (ASMR) is an audio-visual phenomenon that has recently become popular. Many people have reported experiencing a tingling-like sensation through their body while watching audio/video clips known as ASMR clips. People capable of having such experiences have also reported improved overall well-being and feeling relaxed. However, the neural activity underlying this phenomenon is not yet well-studied....
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Coupling between the photoactivity and CO2 adsorption on rapidly thermal hydrogenated vs. conventionally annealed copper oxides deposited on TiO2 nanotubes
PublikacjaHighly ordered spaced titanium dioxide nanotubes were fabricated via electrochemical anodization and modified with titania nanoparticles and copper oxides. Such materials were rapidly annealed in hydrogen atmosphere or conventionally in a tube furnace in air, in which the temperature slowly increases. Applied synthesis procedure can be considered as simple, cost-effective, and environmentally friendly as it allows for reduction...
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Anterior prefrontal EEG theta activities indicate memory and executive functions in epilepsy patients
PublikacjaObjective: Cognitive deficits are one of the most debilitating comorbidities in epilepsy and other neurodegenerative, neuropsychiatric, and neurodevelopmental brain disorders. Current diagnostic and therapeutic options are limited and lack objective measures of the underlying neural activities. In this study, electrophysiological biomarkers that reflect cognitive functions in clinically validated batteries were determined to aid...
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Chemical Origins of Optically Addressable Spin States in Eu2(P2S6) and Eu2(P2Se6)
PublikacjaLanthanide materials with a 4f7 electron configuration (8S7/2) offer an exciting system for realizing multiple addressable spin states for qubit design. While the 8S7/2 ground state of 4f7 free ions displays an isotropic character, breaking degeneracy of this ground state and excited states can be achieved through local symmetry of the lanthanide and the choice of ligands. This makes Eu2+ attractive as it mirrors Gd3+ in exhibiting...
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Substrate Integrated Waveguide-Based Ultra-Compact Self-Heptaplexing Antenna for IoT Connectivity
PublikacjaThis paper introduces an innovative design of a substrate-integrated waveguide (SIW)-based self-heptaplexing antenna (SHA). The proposed structure is implemented using a combination of circular and rectangular HM-SIW cavities. Furthermore, the antenna contains seven individual patches on top of the SIW cavity to operate at seven distinct frequencies. The microstrip feeding technique has been used to activate seven distinct ports....
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Unequally-Spaced Slot Strategy for Radiation Null Reduction in Single SIW-Embedded Antenna Element
PublikacjaThe incorporation of higher-order modes (HOMs) can substantially augment the antenna gain and bandwidth, but this improvement is typically accompanied by compromised radiation performance including radiation nulls and higher side lobe levels. In this study, an inventive strategy is introduced to reduce the radiation nulls and the side lobe levels of a single antenna element by positioning multiple slots of the radiating element...
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Solar light driven degradation of textile dye contaminants for wastewater treatment – studies of novel polycationic selenide photocatalyst and process optimization by response surface methodology desirability factor
PublikacjaThe unplanned anthropogenic activities and raced industrial revolution detrimentally causes serious threat to terrestrial and aquatic life. A high discharge of wastewater from industries using dyes affects living organisms and the environment. This paper presents studies on polycationic selenides (PCS) synthesized by hydrothermal methods for photocatalytic degradation of dyes. The synthesized PCS were confirmed by various characterization...
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Lanthanide ions (Eu3+, Er3+, Pr3+) as luminescence and charge carrier centers in Sr2TiO4
PublikacjaA series of strontium orthotitanate (Sr2TiO4) samples doped with 2% of a mole of europium, praseodymium, and erbium were obtained using the solid-state synthesis method. The X-ray diffraction (XRD) technique confirms the phase purity of all samples and the lack of the influence of dopants at a given concentration on the structure of materials. The optical properties indicate, in the case of Sr2TiO4:Eu3+, two independent emission...
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Polaronic and Mott insulating phase of layered magnetic vanadium trihalide VCl3
PublikacjaTwo-dimensional (2D) van der Waals (vdW) magnetic 3d-transition metal trihalides are a new class of functional materials showing exotic physical properties useful for spintronic and memory storage applications. In this article, we report the synthesis and electromagnetic characterization of single-crystalline vanadium trichloride, VCl 3 , a novel 2D layered vdW Mott insulator, which has a rhombohedral structure (R3, No. 148) at...
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18th European Symposium on Radiopharmacy and Radiopharmaceuticals
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The time-varying low-frequency magnetic-field emitted from the ship’s inverter-fed induction motor
Dane BadawczeThe dataset contains the magnetic field measurement results that are part of a comprehensive study on the assessment of the magnetic field emissions onboard of the research-training vessel. The measurements were carried out, nearby the bow thruster motor fed from the inverter, during maneuvering and the sea voyage. The bow thruster is assembled in the...
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Microcrystalline Cellulose Management in the Production of Poly(ether-urethane)s- Structure, Morphology, and Thermal Characteristic
PublikacjaIn response to the demand of polymer industry for reducing the use of synthetic chemicals, eco-friendly materials are investigated. In the presented study, bio-based poly(ether-urethane)s were prepared by using microcrystalline cellulose (MCC) and polyether polyol and 1,3-propanediol derived from corn sugar. A step towards sustainability was taken by incorporating bio-based compounds and cellulose, consequently, bio-waste are utilized...
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Nested Kriging with Variable Domain Thickness for Rapid Surrogate Modeling and Design Optimization of Antennas
PublikacjaDesign of modern antennas faces numerous difficulties, partially rooted in stringent specifications imposed on both electrical and field characteristics, demands concerning various functionalities (circular polarization, pattern diversity, band-notch operation), but also constraints imposed upon the physical size of the radiators. Conducting the design process at the level of full-wave electromagnetic (EM) simulations, otherwise...
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A spline-based FE approach to modelling of high frequency dynamics of 1-D structures
PublikacjaIn this paper a computational methodology leading to the development of a new class of FEs, based on the application of continuous and smooth approximation polynomials, being splines, has been presented. Application of the splines as appropriately defined piecewise elemental shape functions led the authors to the formulation of a new approach for FEM, named as spFEM, where contrary to the well-known NURBS approach, the boundaries...
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Neutral Dissociation of Pyridine Evoked by Irradiation of Ionized Atomic and Molecular Hydrogen Beams
PublikacjaThe interactions of ions with molecules and the determination of their dissociation patterns are challenging endeavors of fundamental importance for theoretical and experimental science. In particular, the investigations on bond-breaking and new bond-forming processes triggered by the ionic impact may shed light on the stellar wind interaction with interstellar media, ionic beam irradiations of the living cells, ion-track nanotechnology,...
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Charge Transfer, Complexes Formation and Furan Fragmentation Induced by Collisions with Low-Energy Helium Cations
PublikacjaThe present work focuses on unraveling the collisional processes leading to the fragmentation of the gas-phase furan molecules under the He+ and He2+ cations impact in the energy range 5–2000 eV. The presence of different mechanisms was identified by the analysis of the optical fragmentation spectra measured using the collision-induced emission spectroscopy (CIES) in conjunction with the ab initio calculations. The measurements of...
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Insight into Potassium Vanadates as Visible-Light-Driven Photocatalysts: Synthesis of V(IV)-Rich Nano/Microstructures for the Photodegradation of Methylene Blue
PublikacjaPhotocatalysis is regarded as a promising tool for wastewater remediation. In recent years, many studies have focused on investigating novel photocatalysts driven by visible light. In this study, K2V6O16·nH2O nanobelts and KV3O8 microplatelets were synthesized and investigated as photocatalysts. Samples were obtained via the facile method based on liquid-phase exfoliation with ion exchange. By changing the synthesis temperature...
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Properties of Oxygen Vacancy and Hydrogen Interstitial Defects in Strontium Titanate: DFT + Ud,p Calculations
PublikacjaThis work presents extensive theoretical studies focused on the mixed ion-electron transport in cubic strontium titanate (STO). A new approach to the description of this difficult system was developed within the framework of linear-scaling Kohn–Sham density functional theory, as realized in the ONETEP program. The description we present is free of any empirical parameters and relies on the Hubbard U and Hund’s J corrections applied...
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Optical properties of the chemotherapy drugs used in the central nervous system lymphoma therapy: monitoring drug delivery
PublikacjaOur aim is to optically monitor the delivery of the chemotherapy drugs for brain tumours, particularly used in the central nervous system (CNS) lymphoma therapy. In vivo monitoring would help to optimize the treatment and avoiding unnecessary medications. Moreover, it would be beneficial to be able to measure which of the multi-regimen drugs actually do penetrate and how well into the brain tissue. There exist several potential...
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Silicon Oxycarbide (SiOC) Ceramic Materials as Anodes for Lithium Ion Batteries
PublikacjaPolymer derived ceramics (PDCs) have attracted attention as alternative anode material for Li-ion batteries. It has been found that ternary SiOC and SiCN ceramics obtained through pyrolysis of various preceramic polymers display high reversible capacities of 500 – 650 mAh/g. In this work we try to correlate the electrochemical performance of polymer derived silicon oxycarbide with its chemical composition and microstructural features....
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Is It Right To Predict Cutting Forces On The Basis Of Wood Density?
PublikacjaSeveral properties of wood can be correlated to wood density. It is widely accepted that the cutting power requirements are following this general assumption. Therefore, according to classic literature sources available for determination of the cutting power for both band- and circular- sawing machines, the cutting power requirements (and/or cutting forces) are computed as a function of the wood specific gravity SG. It was shown...
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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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Low-cost multiband compact branch-line coupler design using response features and automated EM model fidelity adjustment
PublikacjaDesign closure of compact microwave components is a challenging problem because of significant electromagnetic (EM) cross-couplings in densely arranged layouts. A separate issue is a large number of designable parameters resulting from replacement of conventional transmission line sections by compact microstrip resonant cells. This increases complexity of the design optimization problem and requires employment of expensive high-fidelity...
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Shape-dependent enhanced photocatalytic effect under visible light of Ag3PO4 particles
PublikacjaSilver phosphate (Ag3PO4) could be considered as visible light induced photocatalyst for pollutants degradation, due to its narrow band gap (∼2.4 eV). However, Ag3PO4 photoactivity depends on surface properties and synthesis route. In this study, differently shaped Ag3PO4 photocatalysts have been synthesized through the precipitation, ion exchange, soft-chemical or hydrothermal method. To correlate surface properties with photoactivity all...
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Effect of Polymerization Statistics on the Electronic Properties of Copolymers for Organic Photovoltaics
PublikacjaStatistical block copolymers, composed of donor (D) and acceptor (A) blocks, are a novel type of material for organic photovoltaics (OPVs) devices. In particular a new series of polymers based on PBTZT-stat-BDTT-8, recently developed by Merck, offers high solubility in different solvents, and a high power conversion efficiency (PCE) in different device architectures. Although it is known that the electronic properties of these...
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Unusual Influence of Fluorinated Anions on the Stretching Vibrations of Liquid Water
PublikacjaInfrared (IR) spectroscopy is a commonly used and invaluable tool in the studies of solvation phenomena in aqueous solutions. Concurrently, ab initio molecular dynamics (AIMD) simulations deliver the solvation shell picture at a molecular detail level and allow for a consistent decomposition of the theoretical IR spectrum into underlying spatial correlations. Here, we demonstrate how the novel spectral decomposition techniques...
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Rola światła dziennego w kształtowaniu przestrzeni: Klasyfikacja tradycyjnych oświetleniowych elementów architektonicznych w budynkach w Iranie
PublikacjaDaylight character in a space can be defined as the manner in which daylight permeates and is dispersed in that space. The architectural elements related to daylighting under investigation in this study were rooted in Iranian-Isfahani heritage, considered traditional Iranian architecture (from the 16th to early 20th century). The establishment of a classification system for daylighting systems holds significant utility. This study...
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Physicochemical properties of La0.5Ba0.5Co1-xFexO3-δ (0≤x≤1) as positrode for proton ceramic electrochemical cells
PublikacjaWe report on essential properties of materials in the series La0.5Ba0.5Co1-xFexO3-δ as positrodes for proton ceramic electrochemical cells (PCECs). The unit cell and thermochemical expansion coefficient (TCEC) of these cubic perovskites decrease with iron content x, the TCEC of La0.5Ba0.5FeO3-δ going as low as 11·10-6 1/K. The materials behave as LaMO3 perovskites with small band gaps and Ba acting as acceptors compensated by electron...
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Versatile Unsupervised Design of Antennas Using Flexible Parameterization and Computational Intelligence Methods
PublikacjaDeveloping contemporary antennas is a challenging endeavor that requires considerable engineering insight. The most laborious stage is to devise an antenna architecture that delivers the required functionalities, e.g., multiband operation. Iterative by nature (hands-on topology modifications, parametric studies, trial-and-error geometry selection), it typically takes many weeks and requires considerable engagement from a human...
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Computationally-Efficient Statistical Design and Yield Optimization of Resonator-Based Notch Filters Using Feature-Based Surrogates
PublikacjaModern microwave devices are designed to fulfill stringent requirements pertaining to electrical performance, which requires, among others, a meticulous tuning of their geometry parameters. When moving up in frequency, physical dimensions of passive microwave circuits become smaller, making the system performance increasingly susceptible to manufacturing tolerances. In particular, inherent inaccuracy of fabrication processes affect...
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Frequency Selective Surface Based MIMO Antenna Array for 5G Millimeter-Wave Applications
PublikacjaAbstract: In this paper a radiating element consisting of a modified circular patch is proposed for MIMO arrays for 5G millimeter-wave applications. The radiating elements in the proposed 2×2 MIMO antenna array are orthogonally configured relative to each other to mitigate mutual coupling that would otherwise degrade the performance of the MIMO system. The MIMO array was fabri-cated on Rogers RT/Duroid high frequency substrate...
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Design of a Coplanar Waveguide-Fed Wideband Compact-Size Circularly Polarized Antenna and polarization-sense alteration
PublikacjaThis paper presents the design and validation of a geometrically simple circularly polarized(CP) structure featuring flat gain in the sub-6 GHz 5th generation spectrum. The proposed structure is based on coplanar-waveguide-fed, modified wide slot etched in the ground plane. For generating CP waves, the coplanar ground planes are designed with slight asymmetry in both the horizontal and vertical directions. Furthermore, the ground...
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Generalized Formulation of Response Features for Reliable Optimization of Antenna Input Characteristics
PublikacjaElectromagnetic (EM)-driven parameter adjustment has become imperative in the design of modern antennas. It is necessary because the initial designs rendered through topology evolution, parameter sweeping, or theoretical models, are often of poor quality and need to be improved to satisfy stringent performance requirements. Given multiple objectives, constraints, and a typically large number of geometry parameters, the design closure...
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Nonconventional 1,8-Diazafluoren-9-One Aggregates for Green Light Enhancement in Hybrid Biocompatible Media
PublikacjaOrganic aggregates currently play a prominent role, mainly for their unique optoelectronic properties in the aggregated state. Such properties can be related to the aggregates’ structure and the molecular packing mode. In the literature, we have well-established models of H and J aggregates defined based on the molecular exciton model. However, unconventional aggregates, the most unrecognized forms, have been generating interest...
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Hydrothermal modification of TiO2 nanotubes in water and alkali metal electrolytes (LiNO3, NaNO3, KNO3) – Direct evidence for photocatalytic activity enhancement
PublikacjaThe influence of hydrothermal annealing (HA) of TiO2 nanotubes (TiO2-NTs) in various baths (H2O, LiNO3, NaNO3, KNO3 performed for 4 h, 24 h, 64 h), on their photocatalytic and photoelectrocatalytic properties, was studied. The use of electrolytes was to enable the monitoring of photoactivity changes as a result of the expected impact on the population of hydroxyl groups on the surface. The assumption turned out to be correct and...
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Computationally Efficient Surrogate-Assisted Design of Pyramidal-Shaped 3D Reflectarray Antennas
PublikacjaReflectarrays (RAs) have been attracting considerable interest in the recent years due to their appealing features, in particular, a possibility of realizing pencil-beam radiation patterns, as in the phased arrays, but without the necessity of incorporating the feeding networks. These characteristics make them attractive solutions, among others, for satellite communications or mobile radar antennas. Notwithstanding, available microstrip...
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Synthesis, characteristics, and photocatalytic activity of zinc oxide nanoparticles stabilized on the stone surface for degradation of metronidazole from aqueous solution
PublikacjaAbstract Background: The presence of antibiotics such as metronidazole in wastewater even at low concentrations requires searching for a suitable process such as advanced oxidation process (AOP) to reduce the level of pollutants to a standard level in water. Methods: In this study, zinc oxide (ZnO) nanoparticles were synthesized by thermal method using zinc sulfate (ZnSO4) as a precursor, then, stabilized on stone and was used...
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Solvothermal growth of {0 0 1} exposed anatase nanosheets and their ability to mineralize organic pollutants. The effect of alcohol type and content on the nucleation and growth of TiO2 nanostructures
PublikacjaHerein, the series of {0 0 1} exposed anatase nanosheets from HF-assisted solvothermal growth synthesis were obtained. The two-dimensional TiO2 were characterized, including both bulk (XRD, DR-UV–Vis, Mott-Schottky) and surface characteristics (N2 sorption, XPS, SEM) with experimental results compiled with Density Functional Theory (DFT) calculations. The effect of alcohol amount and type was studied, demonstrating the crucial...
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Improved surface coverage of an optical fibre with nanocrystalline diamond by the application of dip-coating seeding
PublikacjaGrowth processes of diamond thin films on the fused silica optical fibres (10 cm in length) were investigated at various temperatures. Fused silica pre-treatment by dip-coating in a dispersion consisting of detonation nanodiamond (DND) in dimethyl sulfoxide (DMSO) with polyvinyl alcohol (PVA) was applied. Nanocrystalline diamond (NCD) films were deposited on the fibres using the microwave plasma assisted chemical vapour deposition...
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The effect of metal cluster deposition route on structure and photocatalytic activity of mono- and bimetallic nanoparticles supported on TiO2 by radiolytic method
PublikacjaTiO2 (P25) was modified with small and relatively monodisperse mono- and bimetallic clusters (Ag, Pd, Pt, Ag/Pd, Ag/Pt and Pd/Pt) induced by radiolysis to improve its photocatalytic activity. The as-prepared samples were characterized by X-ray fluorescence spectrometry (XRF), photoluminescence spectrometry (PL), diffuse reflectance spectroscopy (DRS), X-ray powder diffractometry (XRD), scanning transition electron microscopy (STEM)...
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Behavioral state classification in epileptic brain using intracranial electrophysiology
PublikacjaOBJECTIVE: Automated behavioral state classification can benefit next generation implantable epilepsy devices. In this study we explored the feasibility of automated awake (AW) and slow wave sleep (SWS) classification using wide bandwidth intracranial EEG (iEEG) in patients undergoing evaluation for epilepsy surgery. APPROACH: Data from seven patients (age [Formula: see text], 4 women) who underwent intracranial depth electrode...
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A newly-developed model for predicting cutting power during wood sawing with circular saw blades
PublikacjaIn the classical approach, cutting forces and cutting power in sawing processes of orthotropic materials such as wood are generally calculated on the basis of the specific cutting resistance kc (cutting force per unit area of cut). For every type of sawing kinematics (frame saws, band saws and circular sawing machines) different empirical values of specific cutting resistance kc have to be applied. It should be emphasised that...
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Quasi-one-dimensional exchange interactions and short-range magnetic correlations in CuTeO4
PublikacjaCuTeO4 has been proposed as a crystallographically distinct, yet electronic structure analog, of the superconducting cuprates. Here, we present a detailed characterization of the physical properties of CuTeO4 to address this proposal. Fitting of magnetic susceptibility data indicates unexpected quasi-one-dimensional, antiferromagnetic correlations at high temperature, with a nearest-neighbor Heisenberg exchange of 1=164(5) K....
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Elucidating charge transfer process and enhancing electrochemical performance of laser-induced graphene via surface engineering with sustainable hydrogel membranes: An electrochemist's perspective
PublikacjaLaser-induced graphene (LIG) has emerged as a promising solvent-free strategy for producing highly porous, 3D graphene structures, particularly for electrochemical applications. However, the unique character of LIG and hydrogel membrane (HM) coated LIG requires accounting for the specific conditions of its charge transfer process. This study investigates electron transfer kinetics and the electroactive surface area of LIG electrodes,...
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A Planar-Structured Circularly Polarized Single-Layer MIMO Antenna for Wideband Millimetre-Wave Applications
PublikacjaIn this paper, a simple geometry, planar-structured printed multiple-input-multiple-output (MIMO) antenna utilizing dual circular polarization (CP) is presented. The proposed numerically and experimentally validated design features a fully grounded coplanar waveguide (CPW) and a systematically perturbed feedline radiator. The fringing electric (E) field along the feedline is altered by extruding periodic stubs on each side of the...
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A Novel Method for Intelligibility Assessment of Nonlinearly Processed Speech in Spaces Characterized by Long Reverberation Times
PublikacjaObjective assessment of speech intelligibility is a complex task that requires taking into account a number of factors such as different perception of each speech sub-bands by the human hearing sense or different physical properties of each frequency band of a speech signal. Currently, the state-of-the-art method used for assessing the quality of speech transmission is the speech transmission index (STI). It is a standardized way...
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The Role of Daylight in Forming the Traditional Space: Classification of Traditional Iranian Daylighting Elements
PublikacjaDaylight character in a space can be defined as the manner in which daylight permeates and is dispersed in that space. The architectural elements related to daylighting under investigation in this study were rooted in Iranian-Isfahani heritage, considered traditional Iranian architecture (from the 16th to early 20th century). The establishment of a classification system for daylighting systems holds significant utility. This...
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Expedited Yield-Driven Design of High-Frequency Structures by Kriging Surrogates in Confined Domains
PublikacjaUncertainty quantification is an important aspect of engineering design, also pertaining to the development and performance evaluation of high-frequency structures systems. Manufacturing tolerances as well as other types of uncertainties, related to material parameters (e.g., substrate permittivity) or operating conditions (e.g., bending) may affect the characteristics of antennas or microwave devices. For example, in the case...