Filtry
wszystkich: 315
wybranych: 266
Filtry wybranego katalogu
Wyniki wyszukiwania dla: PRESSURE PEAK
-
Thermo-Chemical Decomposition Study of Polyurethane Elastomer Through Glycerolysis Route with Using Crude and Refined Glycerine as a Transesterification Agent
PublikacjaDue to the increasing amount of polyurethane waste, chemical recycling of these materials is a topic of growing interest for many researchers. The primary pur- pose of polyurethane feedstock recycling is to recover the starting polyol. In this study glycerolysis using glycerine from two sources and two purity grades is proposed as a method of chemical recycling. The main effort of this paper focuses on the employment of commercial...
-
A benchmark for particle shape dependence
PublikacjaParticle shape is a major parameter for the space-filling and strength properties of granular materials. For a systematic investigation of shape effect, a numerical benchmark test was set up within a collaborative group using different numerical methods and particles of various shape characteristics such as elongation, angularity and nonconvexity. Extensive 2D shear simulations were performed in this framework and the shear strength...
-
Particle shape dependence in 2D granular media
PublikacjaParticle shape is a key to the space-filling and strength properties of granular matter. We consider a shape parameter eta describing the degree of distortion from a perfectly spherical shape. Encompassing most specific shape characteristics such as elongation, angularity and non-convexity, eta is a low-order but generic parameter that we used in a numerical benchmark test for a systematic investigation of shape dependence in sheared...
-
Experimental Study on Effectiveness of a Prototype Seismic Isolation System Made of Polymeric Bearings
PublikacjaSeismic isolation is identified as one of the most popular and effective methods of protecting structures under strong dynamic excitations. Base isolators, such as Lead Rubber Bearings, High Damping Rubber Bearings, and Friction Pendulum Bearings, are widely used in practice in many earthquake-prone regions of the world to mitigate structural vibrations, and therefore minimize loss of life and property damage during seismic events....
-
O 1s excitation and ionization processes in the CO2 molecule studied via detection of low-energy fluorescence emission
PublikacjaOxygen 1s excitation and ionization processes in the CO2 molecule have been studied with dispersed and non-dispersed fluorescence spectroscopy as well as with the vacuum ultraviolet (VUV) photon-photoion coincidence technique. The intensity of the neutral O emission line at 845 nm shows particular sensitivity to core-to-Rydberg excitations and core-valence double excitations, while shape resonances are suppressed. In contrast,...
-
Comparison of the paracetamol electrochemical determination using boron-doped diamond electrode and boron-doped carbon nanowalls
PublikacjaTwo different type of electrodes, boron-doped diamond electrode (BDD) and boron-doped carbon nanowalls (B:CNW) electrode, were used for the electrochemical determination of paracetamol using the cyclic voltammetry and the differential pulse voltammetry in phosphate buffered saline, pH = 7.0. The main advantage of these electrodes is their utilization without any additional modification of the electrode surface. The peak current...
-
Experimental tuning of AuAg nanoalloy plasmon resonances assisted by machine learning method
PublikacjaPlasmonic nanostructures based on AuAg nanoalloys were fabricated by thermal annealing of metallic films in an argon atmosphere. The nanoalloys were chosen because they can extend the wavelength range in which plasmon resonance occurs and thus allow the design of plasmonic platforms with the desired parameters. The influence of initial fabrication parameters and experimental conditions on the formation of nanostructures was investigated....
-
Size effect at aggregate level in microCT scans and DEM simulation – Splitting tensile test of concrete
PublikacjaThe paper describes an experimental and numerical study of size effect on concrete cylindrical specimens in splitting tensile test. Own experimental campaign was performed on specimens with 5 various diameters from D = 74, 105, 150, 192 and 250 mm with hardboard loading strips (distributed load according to standard methods) scaled proportionally to the specimen diameter. The crack opening-control system was applied to obtain the...
-
Low-Dimensional Magnetic Semimetal Cr0.65Al1.35Se3
PublikacjaWhile exploring novel magnetic semiconductors, the new phase Cr0.65Al1.35Se3 was discovered and characterized by both structural and physical properties. Cr0.65Al1.35Se3 was found to crystallize into orthorhombic CrGeTe3-type structure with space group Pnma (no. 62). Vacancies and mixed occupancies were tested, and the results show that one of the 4c sites accommodates a mixture of Cr and Al atoms, while the other 4c site is fully...
-
Circular polarization diversity implementation for correlation reduction in wideband low-cost multiple-input-multiple-output antenna
PublikacjaIn this paper, a multiple-input-multiple-output (MIMO) antenna featuring circular polarization diversity, and designed on a common coplanar ground is presented. The proposed antenna design utilizes a coplanar waveguide (CPW) feeding technique with three parallel coplanar ground planes, and two feedlines in-between. For circular polarization (CP), quasi-loops are created by etching slots on the outermost ground planes. With this...
-
Sensitive determination of isoprostanes in exhaled breath condensate samples with use of liquid chromatography-tandem mass spectrometry
PublikacjaOxidative stress is the hallmark of various inflammatory lung diseases. Increased concentrations of reactive oxygen species in the lungs are reflected by elevated concentrations of oxidative stress markers in the breath, airways, lung tissue and blood. The aim of this work was to develop a method for the fast measurement of F2 isoprostanes in exhaled breath condensate (EBC) samples using equipment which is nowadays available and...
-
Homoisocitrate dehydrogenase from Candida albicans: properties, inhibition, and targeting by an antifungal pro-drug
PublikacjaThe LYS12 gene from Candida albicans, coding for homoisocitrate dehydrogenase was cloned and expressed as a His-tagged protein in Escherichia coli. The purified gene product catalyzes the Mg2+- and K+-dependent oxidative decarboxylation of homoisocitrate to alpha-ketoadipate. The recombinant enzyme demonstrates strict specificity for homoisocitrate. SDS-PAGE of CaHIcDH revealed its molecular mass of 42.6±1 kDa, while in size-exclusion...
-
Wavelet transform-based approach to defect identification in railway carbon contact strips.
PublikacjaPantographs of electric rail vehicles are fitted with carbon contact strips, which slide along the contact wire of catenary to provide constant electrical contact. Contact strips are exposed to wear and damages. Using damaged contact strips significantly increases the risk of catenary rupture. Therefore, their technical condition has to be inspected frequently. In previous work a 3D laser scanning system was proposed for recording...
-
Bearing estimation using double frequency reassignment for a linear passive array
PublikacjaThe paper demonstrates the use of frequency reassignment for bearing estimation. For this task, signals derived from a linear equispaced passive array are used. The presented method makes use of Fourier transformation based spatial spectrum estimation. It is further developed through the application of two-dimensional reassignment, which leads to obtaining highly concentrated energy distributions in the joint frequency-angle domain...
-
COMPLEXITY OF INNOVATIVE FINANCIAL PRODUCTS: THE CASE OF SYNTHETIC EXCHANGE TRADED FUNDS IN EUROPE
PublikacjaThe aim of the text is the presentation of the most important categories of exchange traded funds (ETFs) – physical and synthetic ones. A theoretical part of the text includes an overview of the main features of ETFs, the presentation of differences between physical and synthetic funds and the main risks posed by both types to their users and the whole financial systems. An empirical part focuses on the European market. Time span...
-
Quality Expectations of Mobile Subscribers
PublikacjaMobile systems, by nature, have finite resources. Radio spectrum is limited, expensive and shared between many users and services. Mobile broadband networks must support multiple applications of voice, video and data on a single IP-based infrastructure. These converged services each have unique traffic holding and quality requirements. A positive user experience must be obtained through efficient partitioning of the available wireless...
-
Analysis of airborne metal containing particles with EDX/EDS detectorsin electron microscopes
PublikacjaIn years 2006-2010 particulate matter analysis was undertaken for dust samples collected from Gdansk and London area in orderto compare their morphology and composition. Part of those studies was devoted to analysis of particulate matter (PM) bearingmetals. Characterization of the morphology and size of the particles collected onto the filters was performed using a scanning electronmicroscope (SEM) and transmission electron microscope...
-
Role of quantitative chest perfusion computed tomography in detecting diabetic pulmonary microangiopathy
PublikacjaAims: Aimof the study was to determine the role of perfusion chest computed tomography(pCT) in evaluation of pulmonary diabetic angiopathy.Methods: 18 never-smoking patients (10 diabetic patients and 8 healthy controls) underwentchest high resolution CT (HRCT) and then pCT scanning. In both groups, blood tests,biochemical analysis, fibrinogen, HbA1c, spirometry, diffusion capacity for carbonmonoxide(DLCO) and body pletysmography...
-
Assessment of codes recommendations for the evaluation of the seismic gap of buildings founded on different soil types
PublikacjaSeveral equations have been proposed in the literature to evaluate the seismic gap preventing earthquake-induced structural pounding, such as the ones based on the absolute sum of the peak displacements (ABS), the square root of the sum of the squares (SRSS), the double difference method (DDC), Australian code and the approach proposed by Naderpour et al. The aim of this paper is to investigate the accuracy of these equations taking...
-
Shape Memory Alloy-Based Fluidically Reconfigurable Metasurfaced Beam Steering Antenna
PublikacjaA low-cost actuator-based fluidically programmable metasurface (FPMS) antenna is proposed to solve the slow tuning speed problem of the manually fluidic based reconfigurable antennas. The FPMS-based antenna is probe-fed and comprises a 4 × 4 square ring metasurface as a superstrate. Moreover, two shape memory alloy (SMA)-based electrically-controlled actuators are employed in the design for controlling the position of the 3D-printed...
-
Elucidating photoluminescent properties of Eu‐doped Ca–Al–Si–O(–N) glasses and the local structures of Eu ions
PublikacjaEuropium (Eu) ion–doped luminescent materials have attracted considerable attention for their numerous optical applications. Eu-doped Ca–Al–Si–O(–N) glasses were synthesized from a mixture of oxynitride glasses and Eu2O3 powder using a standard melt-quenching technique in a radiofrequency furnace. The source Eu trivalent ions primarily changed to Eu2+ during melting, and the ratio of Eu2+ ions increased with an increase in Eu content...
-
Hydrothermal reactions: From the synthesis of ligand to new lanthanide 3D-coordination polymers
PublikacjaThe organic ligand 2,5-piperazinedione-1,4-diaceticacid (H2PDA) was synthesized under hydrothermal conditions starting from the iminodiacetic acid and catalyzed by oxalic acid. The X-ray powder diffraction data indicates that the compound crystallizes in the P21/c space group as reported in the literature. The ligand was also characterized by elemental analysis, magnetic nuclear resonance, infrared spectroscopy and thermogravimetric...
-
An Optimal Power Point Tracking Algorithm in a Solar PV Generation System
PublikacjaThe non-linearity in I-V characteristics of a PV panel requires to be operated at knee point to extract maximum power. In order to operate the panel at optimal point, maximum power point tracking (MPPT) algorithm is employed in the control structure. The main objective of MPP tracking is to keep the operation at knee point of I-V characteristics under varying condition of temperature and solar insolation. Under non uniform solar...
-
A Series-Inclined-Slot-Fed Circularly Polarized Antenna for 5G 28-GHz Applications
PublikacjaThis letter presents the design of a single-point-fed, geometrically simple circularly polarized (CP) antenna for 28 GHz Ka-band applications. The proposed antenna is based on a straight microstrip line printed on one side and coupled with the nearly square patches through a 45-degree inclined V-shape slot aperture on the other side. In order to generate circular polarization, the fundamental radiating mode is degenerated at a...
-
Innovative Turbine Intake Air Cooling Systems and Their Rational Designing
PublikacjaThe improved methodology of the engine intake air cooling system designing based on the annual effect due to cooling was developed. It involves determining the optimal value of cooling capacity, providing the minimum system sizes at maximum rate of annual effect increment, and its rational value, providing a close to maximum annual effect without system oversizing at the second maximum rate of annual effect increment within the...
-
Electrochemical determination of nitroaromatic explosives at boron-doped diamond/graphene nanowall electrodes: 2,4,6-trinitrotoluene and 2,4,6-trinitroanisole in liquid effluents
PublikacjaThe study is devoted to the electrochemical detection of trace explosives on boron-doped diamond/graphene nanowall electrodes (B:DGNW). The electrodes were fabricated in a one-step growth process using chemical vapour deposition without any additional modifications. The electrochemical investigations were focused on the determination of the important nitroaromatic explosive compounds, 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitroanisole...
-
The Impact of Spatiotemporal Changes in Land Development (1984–2019) on the Increase in the Runoff Coefficient in Erbil, Kurdistan Region of Iraq
PublikacjaNowadays, geospatial techniques are a popular approach for estimating urban flash floods by considering spatiotemporal changes in urban development. In this study, we investigated the impact of Land Use/Land Cover (LULC) changes on the hydrological response of the Erbil basin in the Kurdistan Region of Iraq (KRI). In the studied area, the LULC changes were calculated for 1984, 1994, 2004, 2014 and 2019 using the Digital Elevation...
-
Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions
PublikacjaAg-based plasmonic nanostructures were manufactured by thermal annealing of thin metallic films. Structure and morphology were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). SEM images show that the formation of nanostructures is influenced by the initial layer thickness as well as the...
-
Electron scattering cross sections for 1-pentene, H2C=CH-(CH2)2CH3, molecules
PublikacjaCross sections, both experimental and theoretical, are reported for electron scattering from 1-pentene (C5H10) molecules. Absolute grand-total cross sections (TCSs) were measured at electron impact energies ranging from 1 to 300 eV, using a linear electron-transmission technique. The dominant behaviour of the experimental TCS energy function is a distinct asymmetric enhancement with the maximum located around 6.5 eV. Discernible...
-
A selection of the optimal eluent components for separation of carnivorous plants metabolites by planar chromatography chromatography
PublikacjaAbstract: The development of the new procedures of the separation components with the complicated chemical structure from natural complex matrix by column chromatography is very difficult and in many cases expensive. Therefore to pre-select the conditions of the separation process the use of thin layer chromatography (TLC) is proffered. The possibility of proceeding the chromatographic process for several mixtures on single plate,...
-
Experimental study of the impact of notches and holes made in the front edge of adherends on the properties of static and fatigue strength of adhesive joints
PublikacjaThe paper presents the results of experimental studies aimed at determining the effect of holes and notches at the front edge of adherends on the strength of adhesive joints. Single-lap joints made of S235JR steel sheets joined with Araldite 2014-2 epoxy adhesive were tested. Comparative tests of static strength in the shear test as well as high-cycle fatigue strength tests were carried out. Joints with three holes with a diameter...
-
Improving Accuracy of Contactless Respiratory Rate Estimation by Enhancing Thermal Sequences with Deep Neural Networks
PublikacjaEstimation of vital signs using image processing techniques have already been proved to have a potential for supporting remote medical diagnostics and replacing traditional measurements that usually require special hardware and electrodes placed on a body. In this paper, we further extend studies on contactless Respiratory Rate (RR) estimation from extremely low resolution thermal imagery by enhancing acquired sequences using Deep...
-
Material Parameters Identification of Historic Lighthouse Based on Operational Modal Analysis
PublikacjaIn the present paper, the identification of the material parameters of a masonry lighthouse is discussed. A fully non-invasive method was selected, in which the material properties were determined via numerical model validation applied to the first pair of natural frequencies and their related mode shapes, determined experimentally. The exact structural model was built by means of the finite element method. To obtain experimental...
-
SiC-Based Power Electronic Traction Transformer (PETT) for 3 kV DC Rail Traction
PublikacjaThe design of rolling stock plays a key role in the attractiveness of the rail transport. Train design must strictly meet the requirements of rail operators to ensure high quality and cost-eective services. Semiconductor power devices made from silicon carbide (SiC) have reached a level of technology enabling their widespread use in traction power converters. SiC transistors oering energy savings, quieter operation, improved reliability...
-
Modeling of wood frame structures with different insulation materials under damaging dynamic loading
PublikacjaWood frame buildings are very popular in regions that are exposed to different dynamic excitations, such as damaging earthquakes. Their seismic resistance is really important in order to prevent structural damages and human losses. This paper presents the results of advanced numerical investigation carried out using the FEM. Based on the models of wall panels, the numerical model of real structure of the wood frame building has...
-
Impact of soluble organic matter and particulate organic matter on anammox system: Performance, microbial community and N2O production
PublikacjaIn this study, the effects of soluble readily biodegradable COD (sCOD) and particulate slowly biodegradable COD (pCOD) on anammox process were investigated. The results of the longterm experiment indicated that a low sCOD/N ratio of 0.5 could accelerate the anammox and denitrification activity, to reach as high as 84.9% ±2.8% TN removal efficiency. Partial denitrification-anammox (PDN/anammox) and denitrification were proposed...
-
Application of Traction Supply System for Charging Electric Cars
PublikacjaThe development of electromobility involves the development of electric cars charging infrastructure. The increase of the number of chargers poses new demands for the AC power grid, especially in regard to its capacity of delivering high peak power. As an alternative for the public AC power grid, urban electrified transportation systems (trams, trolleybuses, and metro) can be used for supplying electric cars chargers. The article...
-
Power Hardware-In-the-Loop Approach for Autonomous Power Generation System Analysis
PublikacjaThe article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies...
-
Cellulosic bionanocomposites based on acrylonitrile butadiene rubber and Cuscuta reflexa: adjusting structure-properties balance for higher performance
PublikacjaDesign and manufacture of cellulosic nanocomposites with acceptable performance is in the period of a transition from fantasy to reality. Typically, cellulosic nanofillers reveal poor compatibility with polymer matrices. Thus, adjusting the balance between structure and properties of cellulosic bionanocomposites by careful selection of parent ingredients is the first priority. Herein, we incorporated Cuscuta reflexa derived cellulose...
-
Compact Electromagnetic Lens Antennas Using Cascaded Metasurfaces for Gain Enhancement and Beam Steering Applications
PublikacjaElectromagnetic (EM) lens antenna designs using cascaded metasurfaces for gain enhancement and beam steering applications are proposed. Two different lens aperture designs are proposed and populated with aperiodic unit cells of size 0.2λo × 0.2λo. In lens Design 1, the unit cells of different phases are distributed in concentric circular zones, whereas in lens Design 2, the unit cells of different phases are distributed in vertical...
-
Highly Miniaturized Self-Diplexed U-Shaped Slot Antenna Based on Shielded QMSIW
PublikacjaThis article presents an efficient yet simple design approach to highly miniaturized cavity-backed self-diplexing antenna (SDA) with high-isolation. The structure employs a shielded quarter-mode substrate integrated waveguide (QMSIW). Two U-shaped slots are engraved on the top conducting plane, which realize two frequency bands and significant size reduction. The slots are excited by two independent 50Ω orthogonal feed-lines to...
-
Numerical investigation on behaviour of cylindrical steel tanks during mining tremors and moderate earthquakes
PublikacjaCylindrical steel tanks are important components of industrial facilities. Their safety becomes a crucial issue since any failure may cause catastrophic consequences. The aim of the paper is to show the results of comprehensive FEM numerical investigation focused on the response of cylindrical steel tanks under mining tremors and moderate earthquakes. The effects of different levels of liquid filling, the influence of non-uniform...
-
Optical and electrical properties of ultrathin transparent nanocrystalline boron-doped diamond electrodes
PublikacjaThe optical properties of ultrathin (less than 100 nm) boron-doped nanocrystalline diamond (B-NCD) film were investigated in a wavelength range of 200 ÷ 20000 nm. The B-NCD refractive index showed values close to that of monocrystalline diamond (n = 2.45) in a broad wavelength range (450 ÷ 4000 nm). A transmittance up to 70% and the average film thickness of 70 nm were achieved. A special cone-shaped shim was used in the deposition...
-
Chemical denudation and the role of sulfide oxidation at Werenskioldbreen, Svalbard
PublikacjaThis study aims to determine the rate of chemical denudation and the relationships between dominant geochemical reactions operating in the proglacial and subglacial environments of the polythermal glacier Werenskioldbreen (SW Svalbard) during an entire ablation season. Water sampling for major ion chemistry was performed at a proglacial hydrometric station and from subglacial outflows from May to September 2011. These data were...
-
Gold nanoparticles for cancer radiotherapy: a review
PublikacjaRadiotherapy is currently used in around 50% of cancer treatments and relies on the deposition of energy directly into tumour tissue. Although it is generally effective, some of the deposited energy can adversely affect healthy tissue outside the tumour volume, especially in the case of photon radiation (gamma and X-rays). Improved radiotherapy outcomes can be achieved by employing ion beams due to the characteristic energy deposition...
-
Linking of adjacent three-storey buildings for mitigation of structural pounding during earthquakes
PublikacjaThe reports after major earthquakes indicate that the earthquake-induced pounding between insufficiently separated buildings may lead to significant damage or even total collapse of structures. An intensive study has recently been carried out on mitigation of pounding hazards so as to minimize the structural damages or prevent collisions at all. The aim of this paper is to investigate the effectiveness of the method when two adjacent...
-
Feasibility study of a Raman spectroscopic route to drug detection
PublikacjaWe present an surface-enhanced Raman spectroscopy (SERS) approach for detection of drugs of abuse in whole human blood. We utilize a near infrared laser with 830 nm excitation wavelength in order to reduce the influence of fluorescence on the spectra of blood. However, regular plasmon resonance peak of plasmonic nanoparticles, such as silver or gold fall in a much lower wavelength regime about 400 nm. Therefore, we have shifted...
-
Miniaturization of ESPAR Antenna Using Low-Cost 3D Printing Process
PublikacjaIn this paper, the miniaturized electronically steerable parasitic array radiator (ESPAR) antenna is presented. The size reduction was obtained by embedding its active and passive elements in polylactic acid (PLA) plastic material commonly used in low-cost 3D printing. The influence of 3D printing process imperfections on the ESPAR antenna design is investigated and a simple yet effective method to...
-
Characteristics of Cucumis metuliferus, Actinidia deliciosa and Musa paradisica fragrance profiles using a comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOF MS)
PublikacjaComprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOF-MS) is a modern analytical technique used in many fields. This technique enables an effective separation of volatile chemical compounds [1]. In recent years, the topic of healthy food and healthy living has become very popular. For this reason, more and more scientific publications related to the analysis of food products...
-
Technical and economic conditions of supplying residential consumers with heat from nuclear power plant
PublikacjaThe reduction of CO2 emission requires technological shift towards carbon-free options. Cogeneration of electricity and heat based on coal and natural gas will experience generation cost increase, if the costs of emissions are imposed on the plant operators. Therefore, nuclear and renewable options should be considered. In this paper, we present the concept of electricity and heat supply system with nuclear condensing turbine adapted...