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Thermal Sensations of Surgeons During Work in Surgical Gowns
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Thermal heat-balance mode flow-to-frequency converter
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Final state of thermal evolution of Jupiter-type planet
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On thermal stability of topological qubit in Kitaev's 4D model
PublikacjaWe analyse stability of the four-dimensional Kitaev model-a candidate for scalable quantum memory - in finite temperature within the weak coupling Markovian limit. It is shown that, below a critical temperature, certain topological qubit observables X and Z possess relaxation times exponentially long in the size of the system. Their construction involves polynomial in system size algorithm which uses as an input the results of...
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Fourier based stabilization of thermal images in dynamic thermography
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The influence of glycols on thermal stability and chemical structure of glycolysates
PublikacjaW pracy omówiono wpływ glikoli (etano-1,2-diolu - heksano-1,6-diolu) na właściwości termiczne oraz budowę chemiczną glikolizatów. Analizy przeprowadzono dla półproduktów wytworzonych w jednym stosunku masowym odpadowego poliuretanu do glikolu wynoszącego 10:1.
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Thermal decomposition of polyurethane pressure-sensitive adhesives dispersions
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Thermal simulation of building performance with different loadbearing materials
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Porosimetric, Thermal and Strength Tests of Aerated and Nonaerated Concretes
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Thermal properties of aluminized and non-aluminized basalt fabrics
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Water mobility and thermal properties of smoked soft cheese
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Negative thermal expansion and antiferromagnetism in the actinide oxypnictide NpFeAsO
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Structure redetermination, transport and thermal properties of the YNi3Al9 compound
PublikacjaSingle crystals of completely ordered variant of the YNi3Al9 compound were grown by self-flux method with excess of aluminum. The crystal structure of the title compound was redetermined from single crystal X-ray diffraction data. The structure adopts ErNi3Al9 type, space group R32, parameters of the unit cell a = 7.2838(2) Å, c = 27.4004(8) Å. The growth of relatively large single crystals of the YNi3Al9 compound, having completely...
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Evaluation of thermal diffusivity variations in multi - layered structures.
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Formulation of the inverse problem in thermal tomography for burn diagnostics.
PublikacjaZdefiniowano zagadnienie odwrotne w analizie przepływów ciepła w strukturach biologicznych, którego rozwiązanie jest niezbędne w tomografii termicznej. Celem jest rekonstrukcja rozkładu właściwości cieplnych w strukturze geometrycznej badanych obiektów. Wektor decyzyjny może być zdefiniowany na podstawie wiedzy o badanym obiekcie. Można wybrać liczbę nieznanych parametrów modelu termicznego tego obiektu. Dla małej liczby niezbędna...
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Analysis of the possibility of increasing thermal-electric energy conversion ratio in CHP units based on micro gas turbine
PublikacjaThe aim of this paper is to analyze the possibility of increasing thermal energy to electricity conversion efficiency in combined heat and power (CHP) units based on micro gas turbine during low heat demand periods. At the beginning sustainable development postulates under power engineering are explained. Next micro CHP as part of distributed generation idea is presented. The main part of the article is based on results of thermodynamic...
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Rheological properties, oxidative and thermal stability, and potential application of biopolyols prepared via two-step process from crude glycerol
PublikacjaIn this work, previously synthesized biopolyols were analyzed in terms of their rheological and thermal properties, very important from the technological point of view. For better evaluation of performed synthesis, the influence of its time and temperature on the properties of biopolyols was determined. In the end, obtained materials were used to prepare rigid polyurethane-polyisocyanurate (PUR-PIR) foams, to evaluate their potential...
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Stability analysis of nanobeams in hygrothermal environment based on a nonlocal strain gradient Timoshenko beam model under nonlinear thermal field
PublikacjaThis article is dedicated to analyzing the buckling behavior of nanobeam subjected to hygrothermal environments based on the principle of the Timoshenko beam theory. The hygroscopic environment has been considered as a linear stress field model, while the thermal environment is assumed to be a nonlinear stress field based on the Murnaghan model. The size-dependent effect of the nanobeam is captured by the nonlocal strain gradient...
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublikacjaIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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Polyurethane/ground tire rubber composite foams based on polyglycerol: processing, mechanical and thermal properties
PublikacjaDuring the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyglycerol, the product of thermo-catalytic polycondensation of waste glycerol, resulting from biodiesel production. Two types of ground tire rubbers, untreated and thermo-mechanically reclaimed, were used to obtain ‘‘green’’ polyurethane-polyglycerol composite foams. Samples were prepared by a single-step method for the ratio of NCO/OH...
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Improving Thermal Insulation Properties for Prefabricated Wall Components Made of Lightweight Aggregate Concrete with Open Structure
PublikacjaPorous concrete is commonly used in civil engineering due to its good thermal insulation properties in comparison with normal concrete and high compression strength in comparison with other building materials. An extremely porous concrete, called ‘lightweight aggregate concrete with open structure’ (LAC), is used in some German plants to produce prefabricated wall components. They are used mainly in hall buildings, e.g. supermarkets....
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The effect of nitrogen on the structure and thermal properties of beryllium-containing Na-(Li)-Si-O-N glasses
PublikacjaTwo 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...
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Thermal stabilization and permanent deformation resistance of LWA/PCM-modified asphalt road surfaces
PublikacjaThis paper presents the results of attempts at reducing the problem of solar overheating of asphalt road pavement surfaces, resulting in weakening and accelerated destruction of the aforementioned structures. To protect pavement surfaces against periodic overheating, standard asphalt mixture AC 16 W 35/50, used for binder course, has been modified by replacing one of the aggregate fractions from the mineral mixture with lightweight...
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Mechanism of Solute and Thermal Characteristics in a Casson Hybrid Nanofluid Based with Ethylene Glycol Influenced by Soret and Dufour Effects
PublikacjaThis article models a system of partial differential equations (PDEs) for the thermal and solute characteristics under gradients (concentration and temperature) in the magnetohydrodynamic flow of Casson liquid in a Darcy porous medium. The modelled problems are highly non-linear with convective boundary conditions. These problems are solved numerically with a finite element approach under a tolerance of 10−8. A numerical algorithm...
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Wybrane zagadnienia modelowania Thermal-FSI określające przepływ płynu i wymianę ciepła na przykładzie benchmarkowego eksperymentu wymiennika ciepła z minikanałami
PublikacjaWybrane zagadnienia modelowania Thermal-FSI określające przepływ płynu i wymianę ciepła na przykładzie benchmarkowego eksperymentu wymiennika ciepła z minikanałami
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Calibration of the thermal desorption-gas chromatography-mass spectrometry system using standards generated in the process of thermal decomposition of chemically modified silica gel
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Influence of Thermal Decomposition of Wood and Wood-Based Materials on the State of the Atmospheric Air. Emissions of Toxic Compounds and Greenhouse Gases
PublikacjaThis paper presents the energy characteristics of wood and wood-based materials in the form of commercially available pellets, furniture board (MDF) and OSB. Toxicometric indices were determined for gaseous destructs arising from thermal decomposition and combustion of the materials studied. The paper proves that combustion conditions are crucial in terms of toxic destructive emissions. It has been shown that the combustion of...
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Structural, mechanical and thermal behavior assessments of PCL/PHB blends reactively compatibilized with organic peroxides
PublikacjaThe efficiency of two commercially available organic peroxides, dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB), during reactive processing of poly (ε-caprolactone)/poly (3-hydroxybutyrate) (PCL/PHB) blends was investigated. The changes in chemical structure of PCL/PHB blends, as a function of organic peroxide type (DCP/BIB) and content (in range: 0–1.0 parts by weight - pbw), were characterized by Fourier...
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Conditions for increasing the recognition of degradation in thermal-flow diagnostics, taking into account environmental legal aspects
PublikacjaThe ever-increasing demand for electricity and the need for conventional sources to cooperate with renewable ones generates the need to increase the efficiency and safety of the generation sources. Therefore, it is necessary to find a way to operate existing facilities more efficiently with full detection of emerging faults. These are the requirements of Polish, European and International law, which demands that energy facilities...
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Thermal Buckling Analysis of Circular Bilayer Graphene sheets Resting on an Elastic Matrix Based on Nonlocal Continuum Mechanics
PublikacjaIn this article, the thermal buckling behavior of orthotropic circular bilayer graphene sheets embedded in the Winkler–Pasternak elastic medium is scrutinized. Using the nonlocal elasticity theory, the bilayer graphene sheets are modeled as a nonlocal double–layered plate that contains small scale effects and van der Waals (vdW) interaction forces. The vdW interaction forces between the layers are simulated as a set of linear springs...
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Curing characteristics, mechanical and thermal properties of reclaimed ground tire rubber cured with various vulcanizing systems
PublikacjaGround tire rubber was thermo-mechanical reclaimed at 120 °C using a co-rotating twin screw extruder. The effect of vulcanizing system type on curing characteristics, static mechanical properties (tensile strength, elongation-at-break, hardness and resilience), dynamic mechanical properties and thermal properties of reclaimed ground tire rubber was investigated. Reclaimed rubber was cured using different types of vulcanization...
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CFD COUPLING OF VOF MODEL WITH ARRHENIUS EQUATION FOR ANALYSIS OF LASER-INDUCED THERMAL DEACTIVATION OF E. COLI
PublikacjaUnderstanding bacterial deactivation at the micro-scale, particularly with E. coli, is crucial for advancing microbiology and has promising applications in biomedical research. In this research contribution, we investigate the thermal inactivation of E. coli bacteria using gold nanoparticles irradiated by a green 1-W laser within a microfluidic chamber. The microfluidic device comprises a fluidic chamber filled with a thin film...
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MODELLING OF TOXIC COMPOUNDS EMISSION IN MARINE DIESEL ENGINE DURING TRANSIENT STATES AT VARIABLE PRESSURE OF FUEL INJECTION
PublikacjaTransient states are an important part of the spectrum of engine loads, especially the traction engines. In the case of marine diesel engines, transient states are of particular importance in reducing the analysis of motion units for special areas and maneuvering in port, the participation of transient states in the load spectrum significantly increases, also, the emission of toxic compounds from this period increases proportionally....
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Elastic multi-layer resilient IP-over-Flexgrid networking: Detailed cost analysis with bandwidth-variable transponders
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A robust optimization model for affine/quadratic flow thinning: A traffic protection mechanism for networks with variable link capacity
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Analysis of the Resistance Change of Chemosensitive Layers to the Presence of Ammonia Vapors under Variable Conditions of Air Temperature and Humidity
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Expedited Globalized Antenna Optimization by Principal Components and Variable-Fidelity EM Simulations: Application to Microstrip Antenna Design
PublikacjaParameter optimization, also referred to as design closure, is imperative in the development of modern antennas. Theoretical considerations along with rough dimension adjustment through supervised parameter sweeping can only yield initial designs that need to be further tuned to boost the antenna performance. The major challenges include handling of multi-dimensional parameter spaces while accounting for several objectives and...
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Structural, thermal and physico-mechanical properties of polyurethane/brewers’ spent grain composite foams modified with ground tire rubber
PublikacjaIn this work, brewers’ spent grain (BSG) and ground tire rubber (GTR) waste fillers were applied as low-cost reinforcement phase in rigid polyurethane foam (PUR). PUR/BSG/GTR composites were prepared by a single step method, using polyglycerol as partial substitute of commercially available petrochemical polyols. Foaming parameters, chemical structure, dynamic mechanical properties, thermal stability, physico-mechanical properties...
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Possibility of thermal imaging use in studies of natural convection heat transfer on the example of an isothermal vertical plate.
PublikacjaA new method of infrared (IR) camera use in convective heat transfer studies has been presented. Until now, IR cameras were utilized for temperature field visualizations of flat heated surfaces of solid objects only. Because liquids and gasses do not emit radiation in the infrared range of wave lengths, detection of temperature field in the air was conducted with the use of plastic mesh, which, after heating by hot air, emits infrared...
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Effect of Variation of Hard Segment Content and Graphene-Based Nanofiller Concentration on Morphological, Thermal, and Mechanical Properties of Polyurethane Nanocomposites
PublikacjaThis 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...
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Impact of Tetrazolium Ionic Liquid Thermal Decomposition in Solvothermal Reaction on the Remarkable Photocatalytic Properties of TiO2 Particles
PublikacjaIonic liquids (ILs) could serve as a structuring agent, a solvent, or a source of dopant during solvothermal synthesis of semiconductors particles. To understand the role of IL during formation of TiO2 particles, it is necessary to study the stability of this IL in solvothermal synthesis conditions, as well as studying the surface properties of formed TiO2 particles. In view of this, the effect of the 2,3,5-triphenyltetrazolium...
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A significance of multi slip condition for inclined MHD nano-fluid flow with non linear thermal radiations, Dufuor and Sorrot, and chemically reactive bio-convection effect
PublikacjaThe aim of this research is to discuss the significance of slip conditions for magnetized nanofluid flow with the impact of nonlinear thermal radiations, activation energy, inclined MHD, sorrot and dufour, and gyrotactic micro motile organisms over continuous stretching of a two-dimensional sheet. The governing equations emerge in the form of partial differential equations. Since the resultant governing differential equations...
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Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation
PublikacjaThe friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic...
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The Influence of a Photovoltaic Micro-Installation on the Low-Frequency Parameters of Electricity at PCC and Its Impact on the Thermal Characteristics of Selected Devices
PublikacjaThis manuscript illustrates the measurement results of parameters describing the quality of energy at the PCC (point of common coupling) of a photovoltaic micro-installation that can significantly affect devices in the same power grid. The analyses reflecting heating of selected devices used in domestic installations, which were performed in an isolated laboratory environment, are also indicated. The conducted study aimed at checking...
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THERMAL ANALYSIS AND DESIGN OF HYBRID MICROCHANNEL-MICROJET TEST PROBE
PublikacjaThe paper presents the numerical investigation of a microjet- microchannel cooling module. In which microjets of water are impinging into the microchannels and forming a liquid film on the impingement surface. Applied technology takes benefits from two very attractive heat removal techniques. When lminar jets are impinging on the surface have a very high kinetic energy at the stagnation point, also in microchannels boundary layer...
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THERMAL ANALYSIS AND DESIGN OF HYBRID MICROCHANNEL -MICROJET TEST PROBE
PublikacjaAccurate control of cooling parameters is required in ever wider range of technical applications. It is known that reducing the flow hydraulic diameter to an increase in the economy of cooling and improves its quality (Mikielewicz and Muszyński 2009). Present study describes research results related to the design and construction of the test stand for hybrid microjet- microchannel cooling modules study, which may be applied in...
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Induction heating laboratory stand for estimating thermal properties of a charge
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Thermal decomposition of surface compounds for the generation of small quantities of acetaldehyde
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Generation of standard gaseous mixtures by thermal decomposition of surface compounds
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Characteristics of Specialised Firefighter Clothing Used in Poland – the Thermal Parameters
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