Search
Filters
total: 1665
filtered: 1401
-
Catalog
Chosen catalog filters
displaying 1000 best results Help
Search results for: DIFFERENTIAL SCANNING CALORIMETRY
-
Weighted Clustering for Bees Detection on Video Images
PublicationThis work describes a bee detection system to monitor bee colony conditions. The detection process on video images has been divided into 3 stages: determining the regions of interest (ROI) for a given frame, scanning the frame in ROI areas using the DNN-CNN classifier, in order to obtain a confidence of bee occurrence in each window in any position and any scale, and form one detection window from a cloud of windows provided by...
-
Influence of alkali metal cations on the photoactivity of crystalline and exfoliated amorphous WO3 – photointercalation phenomenon
PublicationIn order to investigate the effect of photointercalation on photoelectrochemical properties, two types of WO3-based photoanodes, bulk and exfoliated have been prepared and investigated. An aqueous exfoliation method is introduced for the simple fabrication of amorphous and hydrated WO3 nanomaterial using commercial bulk WO3 precursor. The comparison of obtained material with bulk WO3 was performed using Raman, UV–vis, and XPS as...
-
Scaling Up the Process of Titanium Dioxide Nanotube Synthesis and Its Effect on Photoelectrochemical Properties
PublicationIn this work, for the first time, the influence of scaling up the process of titanium dioxide nanotube (TiO2NT) synthesis on the photoelectrochemical properties of TiO2 nanotubes is presented. Titanium dioxide nanotubes were obtained on substrates of various sizes: 2 × 2, 4 × 4, 5 × 5, 6 × 6, and 8 × 8 cm2. The electrode material was characterized using scanning electron microscopy as well as Raman and UV–vis spectroscopy in order...
-
Mechanical Behavior of Bi-Layer and Dispersion Coatings Composed of Several Nanostructures on Ti Substrate
PublicationThree coatings suitable for biomedical applications, including the dispersion coating composed of multi-wall carbon nanotubes (MWCNTs), MWCNTs/TiO2 bi-layer coating, and MWCNTs-Cu dispersion coating, were fabricated by electrophoretic deposition (EPD) on Ti Grade II substrate. Optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and nanoindentation were applied to study topography, chemical, and...
-
Testing of the longest span soil-steel bridge in Europe – new quality in measurements
PublicationThe article describes interdisciplinary and comprehensive diagnostic tests of final bridge inspection and acceptance proposed for a soil – steel bridge made of corrugated sheets, being the European span length record holder (25.74 m). As an effect of an original concept a detailed and precise information about the structure response was collected. The load test design was based on the nonlinear numerical simulations performed by...
-
Effect of Laser Treatment on Intrinsic Mechanical Stresses in Titanium and Some of Its Alloys
PublicationLaser surface treatment conducted at different power levels is an option to modify titanium bone implants to produce nano- and microtopography. However, such processing can lead to excess mechanical stress within the surface layer. This research aims to calculate the level of such residual stresses after the surface processing of Ti grade IV, Ti15Mo, and Ti6Al7Nb alloys with an Nd:YAG laser. Light and scanning electron microscopies...
-
Dynamic Modeling of COVID-19 Disease with Impact of Lockdown in Pakistan and Malaysia
PublicationBeing researchers, it is an utmost responsibility to provide insight on social issues thus, this work addresses the dynamic modeling of first and most contagious disease named as COVID-19 caused by coronavirus. The first case of COVID-19 appeared in Pakistan was on 26th February 2020 and in Malaysia on 27th February 2020; both patients had foreign travel history. In the paper, the number of total affected cases and total deaths...
-
A high-accuracy method of computation of x-ray waves propagation through an optical system consisting of many lenses
PublicationThe propagation of X-ray waves through an optical system consisting of many X-ray refractive lenses is considered. Two differential equations are contemplated for solving the problem for electromagnetic wave propagation: first – an equation for the electric field, second – an equation derived for a complex phase of an electric field. Both equations are solved by the use of a finite-difference method. The simulation error is estimated...
-
Boron-Enhanced Growth of Micron-Scale Carbon-Based Nanowalls: A Route toward High Rates of Electrochemical Biosensing
PublicationIn this study, we have demonstrated the fabrication of novel materials called boron-doped carbon nanowalls (B:CNWs), which are characterized by remarkable electrochemical properties such as high standard rate constant (k°), low peak-to-peak separation value (ΔE) for the oxidation and reduction processes of the [Fe(CN)6]3–/4– redox system, and low surface resistivity. The B:CNW samples were deposited by the microwave plasma-assisted...
-
Low energy elastic scattering of electrons from hexafluoropropene (C3F6)
PublicationWe present cross sections from a joint experimental and theoretical study on elastic electron scattering from hexafluoropropene (C3F6) in the gas phase. The experimental results, using low energy electron spectroscopy, were obtained at incident electron energies of 0.5, 1, 1.5, 2, 3, 4, 5, 6, 10, 12, 15 and 20 eV, for scattering angles ranging from 10°to 130°. The theoretical method used in the computation of the integral, momentum...
-
Assessment of dynamic characteristics of thin cylindrical sandwich panels with magnetorheological core
PublicationBased on the equivalent single-layer linear theory for laminated shells, free and forced vibrations of thin cylindrical sandwich panels with magnetorheological core are studied. Five variants of available magnetorheological elastomers differing in their composition and physical properties are considered for smart viscoelastic core. Coupled differential equations in terms of displacements based on the generalized kinematic hypotheses...
-
New hybrid quadrature schemes for weakly singular kernels applied to isogeometric boundary elements for 3D Stokes flow
PublicationThis work proposes four novel hybrid quadrature schemes for the efficient and accurate evaluation of weakly singular boundary integrals (1/r kernel) on arbitrary smooth surfaces. Such integrals appear in boundary element analysis for several partial differential equations including the Stokes equation for viscous flow and the Helmholtz equation for acoustics. The proposed quadrature schemes apply a Duffy transform-based quadrature...
-
Enhanced stability of electrochemical performance of few-layer black phosphorus electrodes by noncovalent adsorption of 1,4-diamine-9,10-anthraquinone
PublicationIn this paper, the novel noncovalent functionalisation strategy of few-layer black phosphorus by 1,4-diamine-9,10-anthraquinone electrode was proposed and studied. The degradation of few-layer black phosphorus under exposure to oxygen and water is a significant obstacle to its use as an electroanalytical electrode. The anthraquinone compound adsorbed at black phosphorus flakes results in improved prevention of the phosphorus surface...
-
Modular Approach for Modelling Warming Up Process in Water Installations with Flow-Regulating Elements
PublicationThe paper presents a new method for modelling the warming up process of a water system with elements regulating the flow in a stochastic manner. The paper presents the basic equations describing the work of typical elements which the water installation is composed of. In the proposed method, a new computational algorithm was used in the form of an iterative procedure enabling the use of boundary conditions that can be stochastically...
-
On Nonlinear Bending Study of a Piezo-Flexomagnetic Nanobeam Based on an Analytical-Numerical Solution
PublicationAmong various magneto-elastic phenomena, flexomagnetic (FM) coupling can be defined as a dependence between strain gradient and magnetic polarization and, contrariwise, elastic strain and magnetic field gradient. This feature is a higher-order one than piezomagnetic, which is the magnetic response to strain. At the nanoscale, where large strain gradients are expected, the FM effect is significant and could be even dominant. In...
-
Mechanical simulation of artificial gravity in torus-shaped and cylindrical spacecraft
PublicationLarge deformations and stress analyses in two types of space structures that are intended for people to live in space have been studied in this research. The structure under analysis is assumed to rotate around the central axis to create artificial gravitational acceleration equal to the gravity on the Earth's surface. The analysis is fully dynamic, which is formulated based on the energy method by using the first-order shear deformation...
-
Enhanced electrochemical kinetics of highly-oriented (111)-textured boron-doped diamond electrodes induced by deuterium plasma chemistry
PublicationNovel highly-oriented (111)-textured boron-doped diamond electrodes (BDDD) featuring high electrochemical activity and electrode stability toward electrochemical analytics were fabricated by deuterium-rich microwave plasma CVD. The high flux deuterium plasma-induced preferential formation of (111)-faceted diamond as revealed by XRD. The highly-oriented diamond surface exhibited improved boron dopant incorporation and activation,...
-
A New Direct-Sequence Spread Spectrum Signal Detection Method for Underwater Acoustic Communications in Shallow-Water Channel
PublicationDirect-Sequence Spread Spectrum (DSSS) is one of the modulation and coding techniques used in Underwater Acoustic Communication (UAC) systems for reliable data transmision even at low signal levels. However, in a shallow water channel, there is a strong multipath propagation which causes a phase fluctuation of the received signal, affecting the performance of the spread-spectrum system. The article presents a differential method...
-
Application of passive acoustic radar to automatic localization, tracking and classification of sound sources
PublicationA concept, practical realization and applications of the passive acoustic radar to automatic localization, tracking and classification of sound sources were presented in the paper. The device consists of a new kind of multichannel miniature sound intensity sensors and a group of digital signal processing algorithms. Contrary to active radars, it does not emit the scanning beam but after receiving surrounding sounds it provides...
-
Auxetic foams
PublicationThis paper presents a method of producing auxetic polyurethane foams (PUFs) and their unique properties. The experience was based on a synthesis of traditional flexible polyurethane foam and thermal conversion to auxetic foam. The foam specimens were transformed from conventional Poisson's ratio to auxetic (negative Poisson's ratio) [1]. Basic research was performed to determine the mechanical properties and cell structure. Auxetic...
-
A Probe into the Corrosion Behavior of a WE43B Magnesium Alloy in a Simulated Body Fluid using Dynamic Electrochemical Impedance Spectroscopy
PublicationWE43B is one of the newest Mg alloys with practical application in biomedical implant technology. This work attempts to scrutinize the corrosion characteristics of WE43B alloy in a simulated body fluid (SBF) at a typical body temperature. The dynamic-electrochemical impedance spectroscopy with the capacity to track changes on surfaces in a dynamic corrosive system is used in combination with other classical techniques namely, linear...
-
Ultrastructural analysis of the submandibular sialoliths: Raman spectroscopy and electron back-scatter studies
PublicationThe aim of work was the epidemiological analysis of the occurrence of sialolithiasis of the submandibular gland in adults and the evaluation of the ultrastructure of salivary stones. The study sample consisted of 44 sialoliths. Analysis of the structure and chemical composition of sialoliths was performed using a Scanning Electron Microscope and Raman Spectroscopy. Comparing our results with the literature we can say that the epidemiology...
-
Standard deviation as the optimization criterion in the OptD method and its influence on the generated DTM
PublicationReduction of the measurement dataset is one of the current issues related to constantly developing technologies that provide large datasets, eg. laser scanning. It could seems that presence and evolution of processors computer, increase of hard drive capacity etc. is the solution for development of such large datasets. And in fact it is, however, the “lighter” datasets are easier to work with. Additionally, reduced datasets can...
-
Influence of Selected Saccharides on the Precipitation of Calcium-Vaterite Mixtures by the CO2 Bubbling Method
PublicationCalcium carbonate is a compound existing in living organisms and produced for many biomedical applications. In this work, calcium carbonate was synthesized by a CO2 bubbling method using ammonia as a CO2 absorption promotor. Glucose, fructose, sucrose, and trehalose were added into the reaction mixture to modify characteristics of precipitated calcium carbonate particles. To determine the polymorphic form of produced calcium carbonate...
-
The Effect of Calcination Temperature on Structure and Photocatalytic Properties of WO3/TiO2 Nanocomposites
PublicationSeries ofWO3/TiO2 nanocompositeswere obtained by hydrothermal method followed by calcination in the temperature range from 400∘C to 900∘C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900∘C resulted in change of photocatalytic activity under UV-Vis light.Moreover,...
-
Synthesis and structural properties of (Y, Sr)(Ti, Fe, Nb)O3−δ perovskite nanoparticles fabricated by modified polymer precursor method
PublicationThe yttrium, iron and niobium doped-SrTiO3 powders have been successfully fabricated by a modified low–temperature synthesis method from a polymer complex. The usage of strontium hydroxide precursor instead of conventional strontium nitrate or strontium carbonate provides to the possibility of significant decrease of annealing temperature. It allows to prepare a material with sphere-shape grains of nanometric size (15–70 nm). The...
-
Degradation of implantable materials – in vivo and in vitro research
PublicationThe article concerns the biological and electrochemical degradation of metallic implants in vivo and in vitro studies. The in vivo research dealt with degradation of plates used to join bones, as well as endoprostheses. The most common damages were: metalosis, breaking in the microstructure changes, breaking in area of holes, as well as plastic deformation throughout the length of an implant. The material used for the research...
-
The Influence of Substitution of a Phosphorus-Containing Polyol with the Bio-polyol on the Properties of Bio-based PUR/PIR Foams
PublicationIn this work, effects of incorporating of a phosphorus-containing polyol into rigid polyurethane/polyisocyanurate foams’ formulations developed with use of two different bio-based polyols, derived from crude glycerol or liquefied cellulose were examined. The bio-polyol derived from crude glycerol was synthesized via two-step process from crude glycerol and castor oil, whereas the bio-polyol derived from liquefied cellulose was...
-
Effect of cobalt addition on the corrosion behaviorof near equiatomic NiTi shape memory alloy in normal saline solution: electrochemical and XPS studies
PublicationThe electrochemical and corrosion (uniform and localized) behavior of a binary Ni52Ti48 shape memory alloy (SMA) and two ternary Ni52Ti48-xCox (x = 1.5 and 4.0 wt.%) SMAs were studied. Measurements were conducted in 0.9% NaCl solution at 37 oC employing various electrochemical methods. These include: linear polarization resistance (LPR), linear sweep voltammetry (LSV), chronoamperometry and dynamic electrochemical impedance spectroscopy...
-
Softwood-lignin/natural rubber composites containing novel plasticizing agent: Preparation and characterization
PublicationComposite materials based on natural rubber were obtained by using glycerolysate (decomposition prod- uct of polyurethane) as a novel plasticizer. In order to determine the effect of various lignin content, four different filler amounts were used, namely, 5 phr (parts per 100 parts of natural rubber) of lignin (WLI5G), 10 phr (WLI10G), 20 phr (WLI20G), and 40 phr (WLI40G). The reference specimen without lignin (WLI0G) was also...
-
An investigation on the role of GMA grafting degree on the efficiency of PET/PP-g-GMA reactive blending: morphology and mechanical properties
PublicationGlycidyl methacrylate (GMA) has been grafted on polypropylene (PP) with the aid of styrene (St) comonomer, by changing dicumyl peroxide initiator content, GMA level, and St concentration. The performance of the resulting PP-g-GMA reactive material towards static and dynamic mechanical properties of poly (ethylene terephthalate) (PET) was monitored in terms of grafting reaction variables and compatibilizer content. Fourier transform...
-
Porosity and swelling properties of novel polyurethane–ascorbic acid scaffolds prepared by different procedures for potential use in bone tissue engineering
PublicationIn this work, a novel polyurethane (PU) system based on poly(ethylene-butylene) adipate diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol, and ascorbic acid was used to prepare scaffolds with potential applications in bone tissue engineering. Two fabrication methods to obtain porous materials were chosen: phase separation (PS)/salt particle leaching (PL) and solvent casting (SC)/salt PL. The calculated porosity demonstrated...
-
Photocatalytical degradation of toluene and cyclohexane using LED illumination
PublicationA sol-gel process followed by hydrothermal reaction was used to prepare coupled WO3-TiO2 photocatalysts with varying amounts of WO3 in respect to TiO2 (3 mol% and 5 mol% respectively). Additionally, photocatalysts have been subjected to different calcination temperatures of 400ºC and 800ºC, which allowed us to compare how these affect photodegradation efficiency. Photocatalysts were characterized under a scanning electron microscope,...
-
TIME SERIES DATA FOR 3D FLOOD MAPPING
PublicationThanks to the ability to collect information about large areas and with high frequency in time areas threatened by floods can be closely monitored. The effects of flooding are socio-economic losses. In order to reduce those losses, actions related to the determination of building zones are taken. Moreover, the conditions to be met by facilities approved for implementation in such areas are determined. Therefore, satellite data...
-
Solid State Conductivity of Optimized Polypyrrole Coatings on Iron Obtained from Aqueous Sodium Salicylate Solution Determined by Impedance Spectroscopy
PublicationIn this work the optimization procedure for corrosion resistance, surface analysis and electrical properties of PPy-Fe electrodes have been examined. Polypyrrole (PPy) film was electrochemically synthesized in a one step process from an aqueous solution of sodium salicylate and pyrrole with certain concentrations, different parameters and type of polymerization...
-
ZnO coated fiber optic microsphere sensor for the enhanced refractive index sensing
PublicationOptical fiber-based sensors are expected to become key components in the control of industrial processes,and the tuning and the enhancement of their sensing properties are crucial for the further developmentof this technology. Atomic Layer Deposition (ALD), a vapor phase technique allowing for the deposition ofconformal thin films, is particularly suited for the deposition of controllable thin films on challenging sub-strates....
-
The effect of nitrogen on the structure and thermal properties of beryllium-containing Na-(Li)-Si-O-N glasses
PublicationTwo oxynitride glass series with the composition of 35Na2O-5BeO-(60-x)SiO2-xSi3N4 and 9Li2O- 27Na2O-5BeO-(59-x)SiO2-xSi3N4, were prepared. The glasses' topography and structure were studied by Scanning Electron Microscopy and Raman spectroscopy. The composition was analyzed by Inductively Coupled Plasma Optical Emission Spectrometer, SEM-EDS and nitrogen and oxygen elemental analyzer. Na-(Li)-Be-silicate glasses were found to contain...
-
Nickel-nanodiamond coatings electrodeposited from tartrate electrolyte at ambient temperature
PublicationIn this study, nanocrystalline Ni and Ni-diamond coatings were obtained by electrodeposition from tartrate electrolyte at ambient temperature aiming at improving corrosion and wear properties of the material. The created surfaces were investigated with regard to microhardness, adhesion, wear- and corrosion-resistance. The various methods such as atomic force microscopy, scanning electron microscopy, electrochemical impedance spectroscopy...
-
New-fangled sources of cellulose extraction: comparative study of the effectiveness of Cissus latifolia and Ficus benghalensis cellulose as a filler
PublicationRecycled polymers and biopolymers are receiving a great deal of attention these days. If these two can be combined, it will lead to an environment-friendly green material with a great deal of applications. Here the present work is about incorporating bio-based fillers in a recycled polyurethane matrix. Two unusual and extremely novel sources of cellulose have been proposed. The celluloses obtained from Cissus latifolia and Ficus...
-
Antimicrobal and ostheointegration activity of bone cement contains nanometals
PublicationPurpose: One of the major problems in bone surgery are infections – especially thoseoccurring in the course of the operating on the patients with lowered immunity system,because they carry the danger of complications. In the Mechanical Department of TechnicalUniversity of Gdansk, there has been carried the research with the use of bone cement andmetal nanoparticles.Design/methodology/approach: The bone cement was used without supplement...
-
High-density Polyethylene - Expanded Perlite Composites: Structural Oriented Analysis of Mechanical and Thermomechanical Properties
PublicationAs part of this work, research was carried out on the effect of the addition of expanded perlite (PR) on the mechanical and thermomechanical properties of high-density polyethylene (PE) composites. Composites containing from 1 to 10 wt% of the inorganic filler were produced. Polyethylene-based composites manufactured by twin-screw extrusion and formed in the compression molding process were subjected to mechanical, thermomechanical,...
-
Modification of TiO2 nanotubes by graphene–strontium and cobalt molybdate perovskite for efficient hydrogen evolution reaction in acidic medium
PublicationHerein, we demonstrate that modification of TiO2 nanotubes with graphene–strontium and cobalt molybdate perovskite can turn them into active electrocatalysts for hydrogen evolution reaction (HER). For this purpose, a simple method of hydrothermal synthesis of perovskites was developed directly on the TiO2 nanotubes substrate. Moreover, the obtained hybrids were also decorated with graphene oxide (GO) during one-step hydrothermal...
-
Topological extraordinary optical transmission
PublicationΤhe incumbent technology for bringing light to the nanoscale, the near-field scanning optical microscope, has notoriously small throughput efficiencies of the order of 10^4-10^5 or less. We report on a broadband, topological, unidirectionally guiding structure, not requiring adiabatic tapering and, in principle, enabling near-perfect (∼100%) optical transmission through an unstructured single arbitrarily subdiffraction slit at...
-
Effects of laser pulse duration in two-photon vision threshold measurements
PublicationPulsed near-infrared (NIR) light sources can be successfully applied for both imaging and functional testing of the human eye, as published recently1. These two groups of applications have different requirements. For imaging applications, the most preferable is invisible scanning beam while efficiently visible stimulating beam is preferable for functional testing applications. The functional testing of human eye using NIR laser...
-
The Chemical and Biological Properties of Nanohydroxyapatite Coatings with Antibacterial Nanometals, Obtained in the Electrophoretic Process on the Ti13Zr13Nb Alloy
PublicationThe risk of an early inflammation after implantation surgery of titanium implants has caused the development of different antimicrobial measures. The present research is aimed at characterizing the effects of nanosilver and nanocopper dispersed in the nanohydroxyapatite coatings, deposited on the Ti13Zr13Nb alloy, and on the chemical and biological properties of the coatings.The one-stage deposition process was performed by the...
-
Characterization of Highly Filled Glass Fiber/Carbon Fiber Polyurethane Composites with the Addition of Bio-Polyol Obtained through Biomass Liquefaction
PublicationThis work aims to investigate the process of obtaining highly filled glass and carbon fiber composites. Composites were manufactured using previously obtained cellulose derived polyol, polymeric methylene diphenyl diisocyanate (pMDI). As a catalyst, dibutyltin dilaurate 95% and Dabco® 33-LV were used. It was found that the addition of carbon and glass fibers into the polymer matrix causes an increase in the mechanical properties...
-
Novel Class of Proton Conducting Materials—High Entropy Oxides
PublicationHere, for the first time, we present data on proton conductivity of high-entropy, single-phase perovskites. The BaZr0.2Sn0.2Ti0.2Hf0.2Ce0.2O3−δ, BaZr0.2Sn0.2Ti0.2Hf0.2Y0.2O3−δ, BaZr1/7Sn1/7Ti1/7Hf1/7Ce1/7Nb1/7Y1/7O3−δ, and BaZr0.15Sn0.15Ti0.15Hf0.15Ce0.15Nb0.15Y0.10O3−δ single-phase perovskites were synthesized. Before electrical measurements, materials were characterized using X-ray diffraction (XRD), scanning electron microscopy...
-
Incorporation of nitrogen in diamond films – A new way of tuning parameters for optical passive elements
PublicationThis paper investigates the impact of nitrogen incorporation in diamond films for the construction of an interferometric sensor to measure displacement. Diamond films with different nitrogen levels (0–5%) were deposited on silicon substrates by microwave plasma enhanced chemical vapor deposition. The structural characteristics of these samples are characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), confocal...
-
Effect of double thermal and electrochemical oxidation on titanium alloys for medical applications
PublicationThe research focuses on the development and characterization of innovative thin hybrid oxide coatings obtained in subsequent processes of thermal (TO) and electrochemical (EO) oxidation. Four different surface modifications were investigated and the microstructure was determined, the mechanical, chemical and biological properties of the Ti-13Nb-13Zr alloy were assessed using scanning electron microscopy, X-ray dispersion analysis,...
-
Equal Baseline Camera Array—Calibration, Testbed and Applications
PublicationThis paper presents research on 3D scanning by taking advantage of a camera array consisting of up to five adjacent cameras. Such an array makes it possible to make a disparity map with a higher precision than a stereo camera, however it preserves the advantages of a stereo camera such as a possibility to operate in wide range of distances and in highly illuminated areas. In an outdoor environment, the array is a competitive alternative...