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Geminate-pair dissociation yield in systems with exponential energetic disorder — A Monte Carlo study
PublicationGeminate electron–hole recombination in systems with exponential energetic disorder is studied by Monte Carlo method. The field and temperature dependencies of geminate-pair dissociation probability are calculated. It is established that the dissociation yield of carrier pairs depends mainly on the extent of carrier thermalization, which influences the Einstein relationship. The approximate limiting temperature is given by Te =...
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Laser-Assisted Synthesis and Oxygen Generation of Nickel Nanoparticles
PublicationNowadays, more than ever, environmental awareness is being taken into account when it comes to the design of novel materials. Herein, the pathway to the creation of a colloid of spherical, almost purely metallic nickel nanoparticles (NPs) through pulsed laser ablation in ethanol is presented. A complex description of the colloid is provided through UV-vis spectroscopy and dynamic light scattering analysis, ensuring insight into...
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Performance evaluation of the parallel object tracking algorithm employing the particle filter
PublicationAn algorithm based on particle filters is employed to track moving objects in video streams from fixed and non-fixed cameras. Particle weighting is based on color histograms computed in the iHLS color space. Particle computations are parallelized with CUDA framework. The algorithm was tested on various GPU devices: a desktop GPU card, a mobile chipset and two embedded GPU platforms. The processing speed depending on the number...
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Effect of some organic solvent - water mixtures composion on precipitated calcium carbonate in carbonation process
PublicationPrecipitated calcium carbonate particles were obtained during carbonation of calcium hydroxide slurry with carbon dioxide. Aqueous solutions of isopropyl alcohol, n-butanol and glycerol were used as solvents. Concentration of organic additives in the reactive mixture was from 0 to 20 % (vol.). Precipitation process were performed in a stirred tank reactor equipped with gas distributor. Multimodal courses of particles size distribution...
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Offshore surface waters of Antarctica are free of microplastics, as revealed by a circum-Antarctic study
PublicationIn 2018, during a circum navigation of Antarctica below 62° S by the sailing boat Katharsis II, the presence of plastics was investigated with surface sampling nets at ten evenly spaced locations (every 36° of longitude). Although fibres that appeared to be plastic (particles up to 2 cm) were found in numbers ranging from 1 particle (0.002 particles per m3) to 171 particles (1.366 particles per m3) per station, a Fourier-transform...
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Assembly of 1D Granular Structures from Sulfonated Polystyrene Microparticles
PublicationBeing able to systematically modify the electric properties of nano- and microparticles opens up new possibilities for the bottom-up fabrication of advanced materials such as the fabrication of one-dimensional (1D) colloidal and granular materials. Fabricating 1D structures from individual particles offers plenty of applications ranging from electronic sensors and photovoltaics to artificial flagella for hydrodynamic propulsion....
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Efficacy, pharmacokinetics, and safety of the biosimilar CT-P10 compared with rituximab in patients with previously untreated advanced-stage follicular lymphoma: a randomised, double-blind, parallel-group, non-inferiority phase 3 trial
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New methods for assessment and stimulation of non-communicative patients employing advanced multimodal HCI . Nowe metody oceny i stymulacji pacjentów niekomunikatywnych z wykorzystaniem zaawansowanych interfejsów multimodalnych człowiek-komputer
PublicationIn most cases of patients with locomotor system damage it is possible to find a solution to the medical problems originating from the injury. However, it is much more difficult to prevent cognitive and emotional impairments. Therefore, we believe that the technological support of therapists working with such patients on an everyday basis may be essential. We have acquired experience in designing and providing diagnostic and therapeutic...
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GENERAL DYNAMIC PROJECTING OF MAXWELL EQUATIONS
PublicationA complete – system of Maxwell equations is splitting into independent subsystems by means of a special dynamic projecting technique. The technique relies upon a direct link between field components that determine correspondent subspaces. The explicit form of links and corresponding subspace evolution equations are obtained in conditions of certain symmetry, it is illustrated by examples of spherical and quasi-one-dimensional waves.
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Discrete Modelling of Micro-structural Phenomena in Granular Shear Zones
PublicationThe micro-structure evolution in shear zones in cohesionless sand for quasi-static problems was analyzed with a discrete element method (DEM). The passive sand failure for a very rought retaining wall undergoing horizontal translation towards the sand backfill was discussed. To simulate the behaviour of sand, the spherical discrete element model was used with elements in the form of rigid spheres with contacts moments.
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Pumping effect measured by PIV method in a multilayer spike electrode EHD device for air cleaning
PublicationDust particles can be harmful for human health when inhaled. Particularly dangerous are submicrometer dust particles, which can contain traces of toxic elements and can easily penetrate into the human respiratory system. Thus, efficient devices for the air cleaning from submicrometer dust particles are needed. Recently, Katatani and Mizuno have proposed an electrohydrody- namic (EHD) device for air cleaning for submicrometer particles....
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Comparison of PM10 concentration in Gdansk and London using electron microscopy
PublicationParticulate matter (PM) has been considered as one of the most dangerous elements of air pollution. Multiply analytical methods are employed to identify the composition of particles present in the air. The theoretical part of this work is a description of different research centres all over the world where particulate matter is being analyzed using various techniques. The purpose of this project is to analyze and compare particles...
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Precipitation and Transformation of Vaterite Calcium Carbonate in the Presence of Some Organic Solvents
PublicationIn this paper, the production of CaCO3 particles via the carbonation route in the reaction of CaCl2 and CO2, using NH3 as a promoter of CO2 absorption, was studied. The solvents used as the reaction media for CaCO3 precipitation were aqueous solutions of methanol, isopropanol and dimethyl sulfoxide (DMSO), in a concentration range of 0–20% (v/v). It was found that the presence of an organic additive influenced the precipitation...
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“Piglia il bastone e battila molto bene… allora battila, non con animo irato, ma per zelo e carità dell’anima sua.” La violenza domestica secondo alcune testimonianze medievali
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Performance Evaluation of Asphalt Binder Modified with Shear Thickening Fluid
PublicationThis paper aims at using a dilatant or shear thickening fluid (STF) [a non-Newtonian fluid consisting of particles of nano-silica suspended in a liquid medium, i.e., ethylene glycol (EG), which acts as a carrier fluid; proportion 40:60] as additive or modifier of bitumen in order to enhance its viscoelastic properties. A commonly-used performance grading (PG) system, storage stability test, and different conventional and rheological...
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Time-domine Dipole Fields in acoustic and Elektromagnetics
PublicationThe ultrawideband (UWB) radio technique presents a challenge not just for technology. The UWB carrier-free pulses act at a close distance, their electromagnetic fields being very different from classic monochromatic plane wave. The author proposes to adapt a time-domian approach to analysis of broadband spherical fields, both acoustic and electromagnetic, in fundamental cases of quasi-point physical sources.
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Resonant Frequencies in the Open Microstrip Structures Placed on Curved Surfaces
PublicationThe paper presents the research on open microstrip structures placed on curved surfaces such as cylindrical, elliptical or spherical. The numerical analysis of investigated structures is based on expansion of electric and magnetic fields into suitable function series. Utilizing the continuity conditions the boundary problem is formulated which is solved with the use of method of moments. The investigated structures find application...
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A comparative study on selective properties of Kraft lignin–natural rubber composites containing different plasticizers
PublicationEffect of plasticizer type on the kraft lignin–nat- ural rubber composite microstructure and selected proper- ties was determined. The composites were prepared with addition of a commonly used naphthenic oil plasticizer to study the decomposition product of polyurethane (glyc- erolysate) and its characteristics. Kraft lignin powder was incorporated into the natural rubber matrix in amounts of 10 and 40 parts per 100 parts of natural...
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Massively parallel linear-scaling Hartree–Fock exchange and hybrid exchange–correlation functionals with plane wave basis set accuracy
PublicationWe extend our linear-scaling approach for the calculation of Hartree–Fock exchange energy using localized in situ optimized orbitals [Dziedzic et al., J. Chem. Phys. 139, 214103 (2013)] to leverage massive parallelism. Our approach has been implemented in the ONETEP (Order-N Electronic Total Energy Package) density functional theory framework, which employs a basis of non-orthogonal generalized Wannier functions (NGWFs) to achieve...
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Modal FEM Analysis of Ferrite Resonant Structures
PublicationThe finite-element method (FEM) is applied for modal analysis of ferrite-loaded spherical resonators. To improve the efficiency of the numerical calculations, the body-of-revolution (BOR) technique is utilized. Due to the frequency-dependent ferrite permeability, FEM leads to a nonlinear eigenvalue problem that is challenging to solve. To this end, Beyn’s method is proposed. The effectiveness of the proposed approach is confirmed...
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Ag modified ZnO microsphere synthesis for efficient sonophotocatalytic degradation of organic pollutants and CO2 conversion
PublicationThe synthesis and design of non-precious and efficient sonophotocatalyts by an environment friendly technique are requisites for solar energy conversion and environmental remediation. This work reports the preparation of Ag/ZnO microspheres with different Ag contents through deposition–precipitation method for pollutant degradation and CO2 conversion. Detail structural investigation reveals that ZnO microspheres and Ag-ZnO microspheres...
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On the deformation and frequency analyses of SARS-CoV-2 at nanoscale
PublicationThe SARS-CoV-2 virus, which has emerged as a Covid-19 pandemic, has had the most significant impact on people's health, economy, and lifestyle around the world today. In the present study, the SARS-CoV-2 virus is mechanically simulated to obtain its deformation and natural frequencies. The virus under analysis is modeled on a viscoelastic spherical structure. The theory of shell structures in mechanics is used to derive the governing...
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Volumetric incorporation of NV diamond emitters in nanostructured F2 glass magneto-optical fiber probes
PublicationIntegration of optically-active diamond particles with glass fibers is a powerful method of scaling diamond's magnetic sensing functionality. We propose a novel approach for the integration of diamond particles containing nitrogen-vacancy centers directly into the fiber core. The core is fabricated by stacking the preform from 790 soft glass canes, drawn from a single rod dip-coated with submicron diamond particles suspended in...
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Porosity and shape of airborne wear microparticles generated by sliding contact between a low-metallic friction material and a cast iron
PublicationThe wear of brakes in transport vehicles is one of the main anthropogenic sources of airborne particulate matter in urban environments. The present study deals with the characterisation of airborne wear microparticles from a low-metallic friction material / cast iron pair used in car brakes. Particles were generated by a pin-on-disc machine in a sealed chamber at sliding velocity of 1.3 m/s and contact pressure of 1.5 MPa. They...
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Modified nanodiamond particle size studies by means of dynamic light scattering technique
PublicationThe Methods Utilizing the Phenomena of Light Scattering to Measure Particle Size distribution in different solvent, such as deionise water and alcohol and also to study the various structural formation when nanodiamond solution is placed on silicon surface. The purpose of this research project is divided into two parts to configure the measurement units for examining modified nanodiamond particles, examination...
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Modified nanodiamond particle size studies by means of dynamic light scattering technique
PublicationThe Methods Utilizing the Phenomena of Light Scattering to Measure Particle Size distribution in different solvent, such as deionise water and alcohol and also to study the various structural formation when nanodiamond solution is placed on silicon surface. The purpose of this research project is divided into two parts to configure the measurement units for examining modified nanodiamond particles, examination...
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New trifunctional acrylic water-based paint with self-cleaning, biocidal and magnetic properties
PublicationIn the present study, we report the synthesis and application of ZnFe2O4/SiO2-TiO2 nanocomposites with nonstoichiometric content of Fe to Zn used for the first time for the preparation of new generation trifunctional paints with self-cleaning, biocidal and magnetic properties. Currently, there are no compositions on the market for obtaining protective coatings in the form of paint, which simultaneously exhibit biocidal, magnetic...
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Impact analysis of surface roughness of the plate-plate measuring system on resistance torque in interaction with MR fluid
PublicationMagnetorheological (MR) fluids are complex suspensions of magnetic particles in a non-magnetic carrier fluid. They exhibit ‘smart’ properties that enable them to change their rheological parameters in response to a change in the external magnetic field applied. This behavior is used in some engineering solutions, e.g. MR clutches or brakes. For such systems to work correctly, the resistance torque achieved by contact with the...
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abiotic degradation of chlorinated ethanes and ethenes in water
PublicationIntroduction Chlorinated ethanes and ethenes are among themost frequently detected organic pollutants of water. Theirphysicochemical properties are such that they can contaminateaquifers for decades. In favourable conditions, they canundergo degradation. In anaerobic conditions, chlorinatedsolvents can undergo reductive dechlorination.Degradation pathways Abiotic dechlorination is usuallyslower than microbial but abiotic dechlorination...
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Investigation of MIEX® resin sedimentation in the aspect of particle sizes remaining in the supernatant
PublicationThe aim of the study was to evaluate the effectiveness of the MIEX® resin sedimentation process, both new and repeatedly used in hybrid water treatment MIEX®DOC + microfiltration (MF) or ultrafiltration (UF) processes (repeatedly regenerated). The tests consisted of performing 1 h sedimentation of the suspension resin in nonflow conditions and analysis of supernatant water at different process durations. The suspension weight analysis...
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Analysis of effects of formation of non-condensable gases and water vapor during a severe accident in a boiling water nuclear reactor Analiza skutków powstawania niekondensujących gazów i pary wodnej podczas ciężkiej awarii wrzącego reaktora jądrowego
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Rigid polyurethane foams modified with ground tire rubber - mechanical, morphological and thermal studies
PublicationRigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tire rubber particles, i.e. untreated and thermo-mechanically reclaimed by using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tire rubber decreased the velocity of polymerization....
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Discussion on “Coupled effective stress analysis of insertion problems in geotechnics with the Particle Finite Element Method” by L. Monforte, M. Arroyo, J.M. Carbonell, and A. Gens
PublicationAddressed here is the Particle Finite Element Method (PFEM) modelling of undrained CPTu penetration with regard to a reference analytical solution based on the Spherical Cavity Expansion Method (SCEM). Also discussed is the choice of the soil model and its parameters. The effect of cone interface friction on CPTu simulation is analyzed in a series of penetration tests using Arbitrary Lagrangian-Eulerian (ALE) and Updated Lagrangian...
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Application of the Monte Carlo algorithm for solving volume integral equation in light scattering simulations
PublicationVarious numerical methods were proposed for analysis of the light scattering phenomenon. Important group of these methods is based on solving the volume integral equation describing the light scattering process. The popular method from this group is the discrete dipole approximation (DDA). DDA uses various numerical algorithms to solve the discretized integral equation. In the recent years, the application of the Monte Carlo (MC)...
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Influence of Wastewater Treatment Technology on Particle Size Distribution in the Effluent
PublicationSuspended solids in water and wastewater usually carry quite a large load of pollutants (organic substances, nutrients, heavy metals, etc.) adsorbed on the particles surface. Particles of different sizes carry different types and quantities of pollutants. Therefore, particle size distribution is of importance in waster and wastewater treatment. In the article the influence of different treatment technologies on particle size distribution...
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Is the microfiltration process suitable as a method of removing suspended solids from rainwater?
PublicationDue to climate change and anthropogenic pressure, freshwater availability is declining in areas where it has not been noticeable so far. As a result, the demands for alternative sources of safe drinking water and effective methods of purification are growing. A solution worth considering is the treatment of rainwater by microfiltration. This study presents the results of selected analyses of rainwater runoff, collected from the...
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A New Microwave Ceramic – Polymer Composite with 0-3 Connectivity
PublicationGoal of the present research was to fabricate and study two-phase BiNbO4//PVDF composites with 0-3 connectivity. Such composite consists of there-dimensionally connected polymer matrix loaded with dielectric ceramic particles. In the present case BiNbO4 powder acted as an active phase (dispersed phase) whereas polyvinylidene fluoride (PVDF) acted as a non-active (passive) phase (matrix). BiNbO4//PVDF composites with the volume...
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Nanodiamond phantoms mimicking human liver: perspective to calibration of T1 relaxation time in magnetic resonance imaging
PublicationPhantoms of biological tissues are materials that mimic the properties of real tissues. This study shows the development of phantoms with nanodiamond particles for calibration of T1 relaxation time in magnetic resonance imaging. Magnetic resonance imaging (MRI) is a commonly used and non-invasive method of detecting pathological changes inside the human body. Nevertheless, before a new MRI device is approved for use, it is necessary...
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The particle method for simulation of self-organization phenomena
PublicationThe aim of the work was to design, implement, and use, in a number of experiments, an abstract software environment (an artificial world)suitable for modelling systems consisting of many moving and interactingobjects distributed in space. The environment, named DigiHive, is directed towards modeling of complex systems manifested by processes of self-organization, self-reproduction and self modifications. The environment is mainly...
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The overview of reactors used for the production of precipitated calcium carbonate via carbonation route
PublicationCarbonation is one of the methods for the production of precipitated calcium carbonate (PCC) on the industrial scale. A gaseous CO2 is used as a reagent in this process. The hydrodynamic conditions gener-ated in the reactor affect the course of the process and the characteristics of the precipitated calcium carbonate particles. This paper discusses the construction of standard reactors and new proposed con-struction used for the...
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On the generalized model of shell structures with functional cross-sections
PublicationIn the present study, a single general formulation has been presented for the analysis of various shell-shaped structures. The proposed model is comprehensive and a variety of theories can be used based on it. The cross-section of the shell structure can be arbitrarily analyzed with the presented equations. In other words, various types of shell structures, including cylindrical, conical, spherical, elliptical, hyperbolic, parabolic,...
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PROBLEMS WITH CORROSION PROTECTION STEEL STACKS IN FGD SYSTEMS
PublicationThis paper presents problems associated with corrosion of steel stacks and changes in philosophy of corrosion protection when implemented into flue gas desulphurization systems. In-situ tests were taken by means of electrochemical impedance spectroscopy at a stack which discharges flue gas before wet lime/limestone desulphurization. A very rapid soaking of spherical infill vinylester coating with electrolyte has been observed....
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On time-dependent nonlinear dynamic response of micro-elastic solids
PublicationA 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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Synthesis of CoFe2O4 Nanoparticles: The Effect of Ionic Strength, Concentration, and Precursor Type on Morphology and Magnetic Properties
PublicationThe present study highlights the effect of metal precursor types (SO4 2¯, Cl¯, and NO3¯), their concentration, and the influence of ionic strength of reaction environment on the morphology, surface, and magnetic properties of CoFe2O4 particles. The magnetic nanoparticles were obtained by chemical coprecipitation in alkaline medium at increasing metal concentration in the range of 0.0425 mol·dm-3 to 0.17 mol·dm-3 and calcination...
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Oxide nanoparticle exsolution in Lu-doped (Ba,La)CoO3
PublicationThis study investigated Lu doping of Ba0.5La0.5CoO3 and its influence on the exsolution of oxide nanoparticles (NPs). As a result of Lu doping, we observed the phase segregation into the main Ba0.4La0.6Co0.85Lu0.15O3 (BLCO–Lu) phase and the secondary Ba0.85La0.15Co0.75Lu0.25O3 (BCO–Lu) phase. We noticed the exsolution of BCO–Lu nanoparticles on the main BLCO–Lu phase. Moreover, the BLCO–Lu phase exsolved in the form of nanoparticles...
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EXPERIMENTAL AND NUMERICAL INVESTIGATIONS OF CONCRETE BEHAVIOUR AT MESO-LEVEL DURING QUASI-STATIC SPLITTING TENSION
PublicationThe paper describes experimental and numerical results of quasi-static splitting tensile tests on concrete specimens at meso-scale level. The loading strip was made of plywood or steel. Fracture in concrete was detected at the aggregate level by means of three non-destructive methods: 3D x-ray micro-computed tomography, 2D scanning electron microscope and manual 2D digital microscope. The discrete element method was used to directly...
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Micro-modelling of shear localization during quasi-static confined granular flow in silos using DEM
PublicationThe paper deals with the quasi-static confined flow of cohesionless sand in a plane strain model silo with parallel walls and a slowly movable bottom. Numerical modelling was carried out by the discrete element method (DEM) using spheres with contact moments to approximately capture a non-uniform shape of sand particles. Different initial void ratios of sand and silo wall roughness grades were employed. Regular triangular grooves...
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Effect of Microplastics Pollution on Hydrogen Production from Biomass: A Comprehensive Review
PublicationHydrogen production from biomass and organic wastes is considered as a potential alternative energy source and is known as a clean and CO2-free fuel energy carrier. H2 is considered very promising among the other energy sources; therefore, the effective conversion of biomass and organic solid waste to this secondary energy source is urgently sought. As a result, it is of importance to assess the impact of the existence of microplastics...
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Development of novel optoelectronic sensory structures utilising colour centres in nanodiamonds and their interactions with analytes
PublicationThe goal of this dissertation was to develop and assess surface modifications of fluorescent nanodiamonds (NDs) for optical sensing. Three modification routes were tested, each aimed at a different application. Modification with poly-L-lysine (pLys) was verified for optical sensing of pH via an interrelationship between electrically negative (NV¯) and neutral (NV0) nitrogen-vacancy centres. Immobilisation of Ochratoxin A (OTA),...
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Investigation of the Dynamism of Nanosized SOA Particle Formation in Indoor Air by a Scanning Mobility Particle Sizer and Proton-Transfer-Reaction Mass Spectrometry
PublicationTerpenes are VOCs of particular importance, since they are emitted from a wide range of indoor sources and are considered to be precursors of Secondary Organic Aerosol (SOA) formation. It has been proven that SOA particles, especially nanosized ones, pose a threat to human health. In this research, experiments with the application of an environmental chamber and real-time measurement techniques were carried out to investigate in...