Filters
total: 1315
filtered: 900
Search results for: HIGH VALUE OF REDUCED PRESSURE
-
Applying of Doped Graphene Oxide Coatings for Corrosion Prevention
PublicationINTRODUCTION Graphene is a carbonaceous material characterized by extraordinary properties (high electron mobility, high surface area, high mechanical strength of 1100 GPa, very dense network hindering the passage of even the smallest helium atoms) [1]. Therefore, it found many applications, also as an anti-corrosive layer [2]. Electrophoretic Deposition (EPD) is one of the methods to deposit coatings. However, due to slight solubility...
-
Design and Microwave-Assisted Synthesis of TiO2-Lanthanides Systems and Evaluation of Photocatalytic Activity under UV-LED Light Irradiation
PublicationThe TiO2-Eu and TiO2-La systems were successfully synthesized using the microwave method. Based on the results of X-ray diffraction analysis, it was found that regardless of the analyzed systems, two crystal structures were noted for the obtained samples: anatase and rutile. The analysis, such as XPS and EDS, proved that the doped lanthanum and europium nano-particles are present only on the TiO2 surface without disturbing the...
-
Low Power Baseband Processor for M2M Reconfigurable Radio Test Platform
PublicationSoftware Defined Radio (SDR) is becoming more andmore frequently used technique for wireless communication. Itfacilitates as fast prototyping and is a versatile method fordeveloping new communication systems. SDR can be realizedbased on high computational capacity platform, where powerconsumption is no a primary concern like i.e. DVB or BTStransmitters. Another trend are low power systems, whereavailable power in reduced and more...
-
A facile structural manipulation strategy to prepare ultra-strong, super-tough, and thermally stable polylactide/nucleating agent composites
PublicationPolylactide (PLA) is a biodegradable thermoplastic widely used in diferent felds, but it should be adequately modifed considering high-performance applications. However, the current processes for developing PLA materials achieve high strength at the expense of toughness or ductility of the materials. Therefore, there is need to develop new strategies for generation of PLA materials with high strength, great toughness, good ductility,...
-
Future of nature, our future. A preregistered report on future time perspective, social value orientation, and pro-environmental outcomes based on data from Poland and Sweden
PublicationIntroduction: The objective of the study was to examine the role of social value orientation and future time perspective to account for individual differences in pro-environmental behaviors, intentions, and opinions about the link between pro-environmental action and pandemic threat (three separate models) in Polish and Swedish samples expected to differ in rate of pro-environmental behaviors (higher in Sweden). We hypothesized...
-
Microstructure and Electrical Properties of Fe,Cu Substituted (Co,Mn)3O4 Thin Films
PublicationIn this work, thin films (~1000 nm) of a pure MnCo2O4 spinel together with its partially substituted derivatives (MnCo1.6Cu0.2Fe0.2O4, MnCo1.6Cu0.4O4, MnCo1.6Fe0.4O4) were prepared by spray pyrolysis and were evaluated for electrical conductivity. Doping by Cu increases the electrical conductivity, whereas doping by Fe decreases the conductivity. For Cu containing samples, rapid grain growth occurs and these samples develop cracks...
-
Highly stable CsFAPbIBr perovskite solar cells with dominant bulk recombination at real operating temperatures
PublicationMixed-cation mixed-halide perovskite solar cells have been characterized in DC at different temperatures (from −20 °C up to 50 °C) and the time evolution of the device efficiency has been assessed using different degradation protocols (indoors and outdoors). The completely planar p–i–n structure is ITO/CuNiOx/PTAA/CsFAPbIBr/PCBM/PEI/Ag. Pristine current–voltage characteristics barely show hysteresis, at any temperature. Open circuit...
-
Spalanie w cementowniach jako forma odzysku energetycznego opon
PublicationCombustion in cement mills as a form of energy recovery from tiressummary: the subject of used tires is an important issue in poland. in this article, special focus is aimed atmaterial recycling, i.e. tire burning. even though this is not the most energetically effective method, it is one ofthe main techniques used in tire utilization. tires are burned as alternative fuel in already existing cement mills.the high calorific value...
-
Study of the influence of thermal factors on the welding process of polyethylene gas pipelines,
PublicationA one-dimensional calculation scheme is proposed with the help of which it is possible to determine and set the technological parameters with the accuracy to be realized in production conditions: the temperature of the heating element and the heating time, which allows maximum mechanization of the technological operations of polyethylene gas pipelines welding. The numerical value of the coefficient of temperature for polyethylene...
-
Facilitated water transport in composite reduced graphene oxide pervaporation membranes for ethanol upgrading
PublicationHigh purity ethanol is one of the most sought-after renewable energy sources. However, standard production methods yield ethanol of insufficient quality. Membrane processes such as pervaporation are recognized as a viable method for upgrading ethanol. Their performance and selectivity depend solely on membrane employed. Hydrophilic polyvinyl alcohol (PVA) membranes are used industrially for this purpose, but there is a trade-off...
-
Influence of B/N co-doping on electrical and photoluminescence properties of CVD grown homoepitaxial diamond films
PublicationBoron doped diamond (BDD) has great potential in electrical, and electrochemical sensing applications. The growth parameters, substrates, and synthesis method play a vital role in the preparation of semiconducting BDD to metallic BDD. Doping of other elements along with boron (B) into diamond demonstrated improved efficacy of B doping and exceptional properties. In the present study, B and nitrogen (N) co-doped diamond has been...
-
Reduced-Cost Microwave Modeling Using Constrained Domains and Dimensionality Reduction
PublicationDevelopment of modern microwave devices largely exploits full-wave electromagnetic (EM) simulations. Yet, simulation-driven design may be problematic due to the incurred CPU expenses. Addressing the high-cost issues stimulated the development of surrogate modeling methods. Among them, data-driven techniques seem to be the most widespread owing to their flexibility and accessibility. Nonetheless, applicability of approximation-based...
-
Adaptive Sampling for Non-intrusive Reduced Order Models Using Multi-Task Variance
PublicationNon-intrusive reduced order modeling methods (ROMs) have become increasingly popular for science and engineering applications such as predicting the field-based solutions for aerodynamic flows. A large sample size is, however, required to train the models for global accuracy. In this paper, a novel adaptive sampling strategy is introduced for these models that uses field-based uncertainty as a sampling metric. The strategy uses...
-
A Closed Bipolar Electrochemical Cell for the Interrogation of BDD Single Particles: Electrochemical Advanced Oxidation
PublicationA closed bipolar electrochemical cell containing two conductive boron-doped diamond (BDD) particles of size 250 – 350 m, produced by high-pressure high-temperature (HPHT) synthesis, has been used to demonstrate the applicability of single BDD particles for electrochemical oxidative degradation of the dye, methylene blue (MB). The cell is fabricated using stereolithography 3D printing and the BDD particles are located at either...
-
Mapping of Flood-Prone Areas Utilizing GIS Techniques and Remote Sensing: A Case Study of Duhok, Kurdistan Region of Iraq
PublicationOne of the most common types of natural disaster, floods can happen anywhere on Earth, except in the polar regions. The severity of the damage caused by flooding can be reduced by putting proper management and protocols into place. Using remote sensing and a geospatial methodology, this study attempts to identify flood-vulnerable areas of the central district of Duhok, Iraq. The analytical hierarchy process (AHP) technique was...
-
Positron collisions with molecular hydrogen: cross sections and annihilation parameters calculated using theR-matrix with pseudo-states method
PublicationThe molecular R-matrix with pseudo-states (MRMPS) method is employed to study positron collisions with H2. The calculations employ pseudo-continuum orbital sets containing up to h (l = 5) functions. Use of these high l functions is found to give converged eigenphase sums. Below the positronium formation threshold, the calculated cross sections agree with other high-accuracy theories and generally with the measurements. Calculation...
-
Project Management Cycle in the Construction Industry Augmented by Collaborative Innovation Network Software
PublicationProject management is a very broad concept that has in recent times is growing rapidly. Management is especially complex in the construction sector, among the other sectors, due to the high uncertainty of workmanship and complexity of construction projects. Proper project management skills are an important factor in the success of projects, leading to reduced costs and shorten the time of investment. Nevertheless, most of the projects...
-
Recuperator with microjet technology as a proposal for heat recovery from low-temperature sources
PublicationA tendency to increase the importance of so called dispersed generation, based on the local energy sources and the working systems uti- lizing both the fossil fuels and the renewable energy resources is observed nowadays. Generation of electricity on industrial or domestic scale together with production of heat can be obtained for example through employment of the ORC systems. It is mentioned in the EU directive 2012/27/EU for...
-
Conductive Thermoplastic Polyurethane Nanocomposite Foams Derived from a Cellulose/MWCNTs Aerogel Framework: Simultaneous Enhancement of Piezoresistance, Strength, and Endurance
PublicationHigh conductivity and excellent mechanical properties of composite polymers favors their application as piezoresistive strain sensors. Nonetheless, it is difficult to develop composite polymers with desirable piezoresistance, mechanicaland durable properties. Herein, we developed conductive cellulose/MWCNTs aerogel using the freeze-drying technique. Besides, we explored the application of the highly-sensitive piezoresistive polymer...
-
Revalorization of the Szewalski binary vapour cycle
PublicationThe aim of the paper is to revalorizate of the Szewalski binary vapour cycle by analysing thermodynamical and operational parameters of this cycle. This was carried by accessible numerical CFM (Computational Flow Mechanics) codes type, by step-by-step modeling of separates apparatus. The binary vapour cycle is providing steam as the working fluid in the high temperature part of the cycle, while another fluid - a low boiling point...
-
Influence of hydrogen on a nanocrystalline high-entropy oxide with application potential in hydrogen technologies
PublicationThe influence of hydrogen on a (Co0⋅2Cu0⋅2Mg0⋅2Ni0⋅2Zn0.2)O HEO with a rock salt structure was studied. Two forms of this HEO (nanopowder and sinter) were prepared via mechanochemical synthesis (MS) and additional heat treatment, respectively. The chemical stability of the synthesized samples in a pure hydrogen atmosphere was investigated using Sievert’s technique. High-pressure hydrogenation at 250 ◦C had no noticeable effect...
-
Influence of steel brackets supporting crane runway girders structure on the stress distribution in the brackets
PublicationThe paper presents a numerical analysis of steel brackets supporting a double-span crane runway girders. The purpose of the study was to assess the new structural solution based on the stress distribution in the brackets. In order to simplify the connection, the bottom flange of the crane runway girder is based directly on the upper flange of the bracket. As a result, the support reaction is no longer applied in the plane of the...
-
Deep compaction control of sandy soils
PublicationVibroflotation, vibratory compaction, micro-blasting or heavy tamping are typical improvement methods for the cohesionless deposits of high thickness. The complex mechanism of deep soil compaction is related to void ratio decrease with grain rearrangements, lateral stress increase, prestressing effect of certain number of load cycles, water pressure dissipation, aging and other effects. Calibration chamber based interpretation...
-
Influence of Different Biofuels on the Efficiency of Gas Turbine Cycles for Prosumer and Distributed Energy Power Plants
PublicationThe efficiency of a gas turbine can be affected by the use of different biofuels usually with a relatively Lower Heating Value (LHV). The paper evaluates the impact of calorific value of fuel on turbine performance and analyzes the possibilities of optimizing turbine construction from the point of view of maximum efficiency for a particular fuel. The several variants of design of small power microturbines dedicated to various biofuels...
-
ESTIMATION OF THE WILLINGNESS-TO-PAY FOR PRESERVING THE FOOTBALL ARENA IN GDANSK
PublicationThe European Football Championship (Euro 2012) organized in Poland became the pretext for a number of infrastructural changes. A high level of expenditure makes the Polish event the most expensive among events of this magnitude. The fact that these changes were 100% financed by public funds raises the question of whether these funds were used in a substantiated way. Therefore, the aim of this study is...
-
Optimizing CO2 Purification in a Negative CO2 Emission Power Plant
PublicationIn the pursuit of mitigating CO2 emissions, this study investigates the optimisation of CO2 purification within a Negative CO2 Emission Power Plant using a spray ejector condenser (SEC) coupled with a separator. The approach involves direct-contact condensation of vapour, primarily composed of an inert gas (CO2), facilitated by a subcooled liquid spray. A comprehensive analysis is presented, employing a numerical model to simulate...
-
Antimicrobial Activity of Honey
PublicationHoney has had a valued place in traditional medicine for centuries. It was used to overcome liver, cardiovascular and gastrointestinal problems and for treatment of some types of infectious disease. Particularly, good results were achieved in the case of application of this product for therapy of infected, difficult to heal wounds. The high health-promoting properties of honey have been recently confirmed in many research investigations....
-
Implementation of power transformer controlled switching algorithm
PublicationThe article presents two new algorithms of controlled switching the power transformer. The main aim of the paper is to obtain formulas that determine the moments of closing of the circuit breaker poles. The study contains projects of control systems for both algorithms. Mathematical formulas for the time instants of the breaker poles closing were developed on the basis of electric circuit theory and magnetic circuit theory. The...
-
Reduced-cost electromagnetic-driven optimisation of antenna structures by means of trust-region gradient-search with sparse Jacobian updates
PublicationNumerical optimisation plays more and more important role in the antenna design. Because of lack of design-ready theoretical models, electromagnetic (EM)-simulation-driven adjustment of geometry parameters is a necessary step of the design process. At the same time, traditional parameter sweeping cannot handle complex topologies and large number of design variables. On the other hand, high computational cost of the conventional...
-
Synthesis and modification of reduced graphene oxide aerogels for biofuel cell applications
PublicationWe have carried out the preparation of reduced graphene oxide aerogels using eco-friendly method that is based on the Hummers method of graphite oxidation without the use of NaNO3 that produces toxic gases. To obtain a porous 3D structure of reduced graphene oxide, we performed the hydrothermal reduction at elevated temperature. We also prepared the rGO aerogel/CNT composite using multiwalled carbon nanotubes as linkers. The rGO...
-
Physiological Biomarkers Assessed by Low‐Tech Exercise Tests Predict Complications and Overall Survival in Patients Undergoing Pneumonectomy Due to Lung Cancer
PublicationDue to its debilitating character pneumonectomy this is last‐resort procedure. Preoperative results of the 6‐min walking test (6MWT) help to identify high risk of postoperative complications and increased mortality in patients undergoing lobectomy for lung cancer. The aim of the study was to validate the value of 500 m in 6MWT as an indicator, which differentiates risk of complications in patients undergoing pneumonectomy. 125...
-
Wykorzystanie kamery termowizyjnej nowej generacji do oceny wpływu sił ortodontycznych na dziąsło = The application of a new-generation thermal imaging camera for the assessment of hemodynamic changes in gingiva during orthodontic treatment
PublicationIntroduction. One ot the most interesting modern methods of assessing microcirculation is thermovisiual examination. Thermovision cameras are commonly used in general medicine. As the periodontium is one of the most vascularized tissues in the human body, the application of high-sensitivity thermovision cameras may allow tor noninvasive asses- sment and early detection ot pathological changes in the gingiva by giving a complete...
-
Analysis of Residual Stresses and Dislocation Density of AA6082 Butt Welds Produced by Friction Sir Welding
PublicationThe Friction Stir Welding (FSW) method was employed to join AA6082 sheets. The welds were produced with different tool traverse speed (200 and 250 mm/min), rotational speed (1000 and 1250 RPM) and tool tilt angle (0 and 2 deg). Based on the analysis of XRD patterns, the total precipitation volume fractions in the nugget zones and the base material were calculated. The FSW process resulted in a reduction in the fraction of precipitates...
-
Mechanical Properties of Bio-Composites Based on Epoxy Resin and Nanocellulose Fibres
PublicationThe aim of our research was to investigate the effect of a small nanocellulose (NC) addition on an improvement of the mechanical properties of epoxy composites. A procedure of chemical extraction from pressed lignin was used to obtain nanocellulose fibers. The presence of nanoparticles in the cellulose pulp was confirmed by FTIR/ATR spectra as well as measurement of nanocellulose particle size using a Zetasizer analyzer. Epoxy...
-
Wielopoziomowy przekształtnik trakcyjny SiC z izolacją od sieci 3kV DC realizowaną za pomocą transformatorów 30kHz do napędów EZT
PublicationW referacie przedstawiono wielopoziomowy izolowany kaskadowy przekształtnik DC-AC z tranzystorami SiC MOSFET 1,2kV, przeznaczony do napędów elektrycznych zespołów trakcyjnych (EZT). Zaproponowana konstrukcja przekształtnika, przeznaczonego do pracy przy zasilaniu z sieci trakcyjnej 3kV DC, spełnia założenia energoelektronicznego transformatora trakcyjnego (z ang. Power Electronic Traction Transformer). Budowa modułowa z niskonapięciowych...
-
How does climate change affect ice formation and presence in rivers, lakes and oceans, as well as its impact on infrastructure
PublicationIce season in rivers, lakes, seas and oceans is sensitive to climate change due to the high homologous temperature. Two vital aspects of the predicted climate change are increasing average air temperature and increasing variability in the weather. These cause delayed formation of ice, thinner ice and shorter duration of seasonal ice covers, the geographical ice margin to move further away from the equator, the perennial ice to...
-
MECHANICAL PROPERTIES OF BOTTOM ASH – DREDGED MATERIAL MIXTURES IN LABORATORY TESTS
PublicationBottom ash from EC Gdańsk and dredged material taken from the mouth of The Vistula were mixed to form an engineering material used for dike construction. Mixtures with different bottom ash content were tested in laboratory to determine its basic physical and mechanical properties. The optimum bottom ash–dredged material mixture, built in the corps of the test dike, contains 70% of ash. The optimum bottom ash content in the mixture...
-
Hybrid model of geared rotor system
PublicationIn the paper a hybrid model of a geared multirotor system has been developed. The model is obtained by application of both the modal decomposition methodology and the spatial discretization method. Reduced modal model was constructed for the system without gyroscopic and damping effects. The gyroscopic interaction, damping and other phenomena which are difficult to include in the modal approach were modeled by application of simply...
-
Effect of Variation of Hard Segment Content and Graphene-Based Nanofiller Concentration on Morphological, Thermal, and Mechanical Properties of Polyurethane Nanocomposites
PublicationThis study describes the development of a new class of high-performance polyurethane elastomer nanocomposites containing reduced graphene oxide (RGO) or graphene nanoplatelets (GNP). Two types of polyurethane elastomers with different contents of hard segments (HS) were used as a polymer matrix. The developed nanocomposites were characterized by thermal analysis (DSC, TG), dynamic mechanical testing (DMA), hardness testing, mechanical...
-
Numerical investigation of multiphase blood flow coupled with lumped parameter model of outflow
PublicationPurpose The purpose of this paper is the application of the computational fluid dynamics model simulating the blood flow within the aorta of an eight-year-old patient with Coarctation of Aorta. Design/methodology/approach The numerical model, based on commercial code ANSYS Fluent, was built using the multifluid Euler–Euler approach with the interaction between the phases described by the kinetic theory of granular flow (KTGF). Findings A...
-
Novel Structures and Applications of Graphene-Based Semiconductor Photocatalysts: Faceted Particles, Photonic Crystals, Antimicrobial and Magnetic Properties
PublicationGraphene, graphene oxide, reduced graphene oxide and their composites with various compounds/materials have high potential for substantial impact as cheap photocatalysts, which is essential to meet the demands of global activity, offering the advantage of utilizing “green” solar energy. Accordingly, graphene-based materials might help to reduce reliance on fossil fuel supplies and facile remediation routes to achieve clean environment...
-
Comparative study of a bottoming SRC and ORC for Joule–Brayton cycle cooling modular HTR exergy losses, fluid-flow machinery main dimensions, and partial loads
PublicationEnergy conversion efficiency increase in power plants with high-temperature gas-cooled reactors via implementation of the bottoming cycle was investigated under nominal and minimal thermal load of a high-temperature reactor (HTR). Heat transfer surface area and turbine outlet volumetric flow rate in bottoming cycles was also investigated. Water and two low-boiling point working fluids (ammonia and ethanol) were analyzed. Analyzed...
-
Low-Profile ESPAR Antenna for RSS-Based DoA Estimation in IoT Applications
PublicationIn this paper, we have introduced a low-profile electronically steerable parasitic array radiator (ESPAR) antenna that can successfully be used to estimate the direction-of-arrival (DoA) of incoming signals in wireless sensor network (WSN) applications, in which the height of the complete antenna has to be low. The proposed antenna is over three times lower than high-profile ESPAR antenna designs currently available in the literature...
-
A study of a compact high-efficiency zero-emission power plant with oxy-fuel combustion
PublicationThis paper discusses the application of global trends in gas cycles technology using oxy-fuel combustion. This is followed by a demonstration of a design solution for a new cycle with two enhanced energy-converting devices, namely a wet combustion chamber and a spray-ejector condenser. The proposed gas and steam cycle unit is contained within a single turbine, whose benefits combine those offered by gas turbines (high inlet temperatures)...
-
Detailed studies of superconducting properties of Y2Pd1.25Ge2.75
PublicationWe report a successful synthesis of a high-purity intermetallic germanide Y2Pd1.25Ge2.75, crystallizing in the disordered variant of the AlB2-type structure. A single-phase sample was obtained via arc-melting by deliberately tuning the composition out of the ideal 2:1:3 ratio. Specific heat, electrical resistivity and magnetization measurements show that the compound is a weakly-coupled (λ e-p = 0.58) type-II superconductor with...
-
New satellite pumps
PublicationStosowanie Maszyn company from Katowice was initiator and originator of newest original high pressure satellite pumps series of types PSM. Construction solution, research and development of these pumps have been conducted by Team of Hydraulics and Pneumatics of Gdansk University of Technology in cooperation with this company within the confines of research project nr R0300103 (source of funds: Ministry of Science and Higher Education)....
-
Optical Magnetometry Based on Nanodiamonds with Nitrogen-Vacancy Color Centers
PublicationNitrogen-vacancy color centers in diamond are a very promising medium for many sensing applications such as magnetometry and thermometry. In this work, we study nanodiamonds deposited from a suspension onto glass substrates. Fluorescence and optically detected magnetic resonance spectra recorded with the dried-out nanodiamond ensembles are presented and a suitable scheme for tracking the magnetic-field value using a continuous...
-
Diamond-Phase (Sp3-C) Rich Boron-Doped Carbon Nanowalls (Sp2-C): A Physico-Chemical And Electrochemical Properties
PublicationThe growth of B-CNW with different boron doping levels controlled by the [B]/[C] ratio in plasma, and the influence of boron on the obtained material’s structure, surface morphology, electrical properties and electrochemical parameters, such as -ΔE and k°, were investigated. The fabricated boron-doped carbon nanowalls exhibit activity towards ferricyanide redox couple, reaching the peak separation value of only 85 mV. The flatband...
-
Understanding the kinetics and atmospheric degradation mechanism of chlorotrifluoroethylene (CF2=CFCl) initiated by OH radicals
PublicationThe atmospheric degradation of chlorotrifluoroethylene (CTFE) by OH˙ was investigated using density functional theory (DFT). The potential energy surfaces were also defined in terms of single-point energies derived from the linked cluster CCSD(T) theory. With an energy barrier of −2.62 to −0.99 kcal mol−1 using the M06-2x method, the negative temperature dependence was determined. The OH˙ attack on Cα and Cβ atoms (labeled pathways...
-
Pyrolysis and Torrefaction—Thermal Treatment of Creosote-Impregnated Railroad Ties as a Method of Utilization
PublicationA fundamental issue of waste management and the rail transport industry is the problem of utilizing used railroad ties. Wooden railroad ties are treated with a preservative, usually creosote. Due to their high toxicity, railroad ties are considered hazardous waste and must be utilized under various directives. It is proposed to utilize the troublesome waste by using the pyrolysis and torrefaction process. The research proves that...