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Search results for: PRESSURE EFCIENCY
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Electrically conductive acrylic pressure-sensitive adhesives containing carbon black
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Thermal degradation of poly(alkyl methacrylates) and polyurethane pressure-sensitive adhesives
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Effect of concentration boundary layers on mechanical pressure in a double-membrane system
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Neon-Bearing Ammonium Metal Formates: Formation and Behaviour under Pressure
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The oxidation of limonene at raised pressure and over the various titanium-silicate catalysts
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Blood Pressure celebrates 20 years of dedication to Nordic hypertension research
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The Effect of Herbal Supplements on Blood Pressure: Systematic Review and Meta-Analysis
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Influence of initial density of cohesionless soil on evolution of passive earth pressure
PublicationArtykuł porusza problem odporu bezkohezyjnego gruntu. Obliczenia wykonano wykorzystując metodę elementów skończonych na bazie mikropolarnego prawa hipolastycznego. W obliczeniach przyjęto różne początkowe zagęszczenia oraz średnice cząstek gruntu.
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Luminescence of Ca(NbO3)2:Pr3+ at ambient and high hydrostatic pressure
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Pressure-induced phase transition in LiLuF4:Pr3+investigated by an optical technique
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Luminescence Spectra of β-SiAlON/Pr3+ Under High Hydrostatic Pressure
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High pressure and time resolved luminescence spectra of Gd3Ga5O12:Pr3+ crystal
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Luminescence of Gd2(WO4)3:Ln3+at ambient and high hydrostatic pressure
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Influence of high hydrostatic pressure on Eu2+-luminescence in KMgF3:Eu2+ crystal
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High pressure luminescence spectra of CaMoO4:Ln3+(Ln = Pr, Tb)
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Influence of storage time on the useful properties of silicone pressure-sensitive adhesives
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Influence of cleaned granite dust on the properties of silicone pressure-sensitive adhesives
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The accuracy of SpaceLabs 90207 in blood pressure monitoring in patients with atrial fibrillation
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Influence of Nanoclay on the Thermo-Mechanical Properties of Silicone Pressure-Sensitive Adhesives
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Thermal crosslinking of silicone pressure-sensitive adhesives using organic peroxides
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The INTERSALT Study and the complex relationship between salt intake and blood pressure
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Influence of UV on the self-adhesive properties of silicone pressure-sensitive adhesives
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Carboxymethylated polysaccharide-based films as carriers for acrylic pressure-sensitive adhesives
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Pressure drop and heat transfer during boiling and condensation at subcritical region
PublicationMost of the data presented in the literature relate to saturation temperatures in the range - 20°C to 40°C due to the application in refrigeration technology. There is necessity to extend databases to higher values of saturation temperature due to new applications such as Organic Rankine Cycle and high temperature heat pumps. Only few papers contain data for high reduced pressure for low boiling point liquids. This paper focus...
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Numerical calculation wall pressure and stresses in cylindrical silos withconical hopper
PublicationOmówiono wyniki numerycznego obliczania naporu materiału sypkiego na ściany silosu. Obliczenia wykonano stosując metodę elementów skończonych i sprężysto idealnie plastyczne prawo konstytutywne według Druckera-Pragera. W analizie uwzględniono wpływ osiowy i mimośrodowy.
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Diversification of investment efficiency in selected economies
PublicationAn assessment of the effectiveness of investments is a key element of investment processes. In order to be comprehensive and exhaustive, it should go beyond the scope of the microeconomic assessment and take into account the macroeconomic calculation of effectiveness. The prerequisite for the effectiveness of investment decisions implemented by private companies is the maximization of the return on the investments. When attempting...
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On a Method of Efficiency Increasing in Kaplan Turbine
PublicationThis paper presents a method of increasing efficiency in Kaplan-type turbine. The method is based on blade profile optimisation together with modelling the interaction between rotor and stator blades. Loss coefficient was chosen as the optimisation criterion, which is related directly to efficiency. Global optimum was found by means of Genetic Algorithms, and Artificial Neural Networks were utilised for approximations to reduce...
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Efficiency of acoustic heating in the Maxwell fluid
PublicationThe nonlinear effects of sound in a fluid describing by the Maxwell model of the viscous stress tensor is the subject of investigation. Among other, viscoelastic biological media belong to this non-newtonian type of fluids. Generation of heating of the medium caused by nonlinear transfer of acoustic energy, is discussed in details. The governing equation of acoustic heating is derived by means of the special linear combination...
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Efficiency of acoustic heating in the Maxwell fluid
PublicationThe nonlinear effects of sound in a fluid describing by the Maxwell model of the viscous stress tensor is the subject of investigation. Among other, viscoelastic biological media belong to this non-newtonian type of fluids. Generation of heating of the medium caused by nonlinear transfer of acoustic energy, is discussed in details. The governing equation of acoustic heating is derived by means of the special linear combination...
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ANALYSIS OF ENERGY EFFICIENCY IN ELECTRIC DRIVES
PublicationIn this paper energy efficiency in electric drives is analysed. This factor strongly depends on energy parameters - efficiency n and power factor k (in special case cos fi)
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Lightning impulse efficiency of horizontal earthings
PublicationSystem uziemień współczesnych obiektów jest zwykle bardzo rozległy, a na łączenie poszczególnych elementów uziemiających za pomocą głównej szyny wyrównania potencjałów uwzględnia także uziemienia stacji transformatorowej. Ocena przydatności takiego systemu uziemień do celów ochrony odgromowej nie jest prosta, bo tylko jego część określana, jako długość efektywna bierze udział w odprowadzaniu do gruntu prądu piorunowego. Praca zawiera...
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Flow visualization and heat transfer investigations on the flat plate with streamwise pressure gradient
PublicationPaper presents experimental investigations results for film cooling on a flat plate. The main objective of the design is the streamwise pressure distribution on the flat plate as in the blade cascade. The transient and steady-state technique with liquid crystals for the surface temperature distribution with film cooling has been used in experiments in a low speed wind tunnel.
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Public Participation practice versus economic pressure: transformation of the Gdansk Coastal Strip
PublicationThe paper focuses on the issue of public participation in the areas that are particularly sensitive to the transformation processes based on the case study of Gdańsk Coastal Strip. Moreover the article presents the outcome of an innovative attempt at promotion of public participation introduced in university education that was built on the experiences gathered during elaboration of the pro publico bono project of the Coastal Strip...
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Determination of Earth Pressure and Displacement of the Retaining Structure According to the Eurocode 7-1
PublicationComparative analysis of standard guidelines and findings given in EC7-1 and in Polish Standard PN-83/B-03010. Discussed guidelines concerning active and passive earth pressure as well as at rest pressure state. Wall displacement causing limit states of earth pressure and resistance. Interactive assumptions concerning intermediate earth pressure and resistance values. Conclusions and final remarks.
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Influence of pressure on heat transfer during pool boiling on smooth tube bundle
PublicationPrzedstawiono wyniki badań eksperymentalnych wrzenia wody, metanolu i R141b na pęu rur głądkich w warunkach podcisnienia i ciśnienia atmosferycznego
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Effect of pH and high pressure at sub-zero temperature on the viability of some bacteria
PublicationCelem badań było określenie przeżywalności Escherichia coli i Staphylococcus aureus zawieszonych w soku jabłkowym (pH 3,8) po działaniu ciśnienia 193MPa w temperaturze -20°C. Stwierdzono, że bezpośrednio po działaniu ciśnienia przeżywalność badanych szczepów bakterii nie zmieniała się znacząco. Jednakże liczba komórek zmniejszała się z czasem przechowywania ciśnieniowanych prób. Żywe komórki mikroorganizmów nie były wykrywane w...
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Influence of geometric imperfections on capacities of silo structures loaded with pressure below atmospheric
PublicationPrzedstawiono probabilistyczną analizę nośności aluminiowego silosu ze wstępnymi imperfekcjami geometrycznymi obciążonego podciśnieniem. Imperfekcje opisano za pomocą dyskretnych odchyłek przyjętych zgodnie z maksymalnymi niedokładnościami dopuszczonymi przez normy. Ponadto wygenerowano imperfekcje płaszcza silosu, stosując jednorodne i niejednorodne pola losowe. Wykonano numeryczne obliczenia geometrycznie i materiałowo nieliniowe.
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Upscaling unsaturated flow in binary porous media with air entry pressure effects
PublicationArtykuł dotyczy przepływu w gruntach nienasyconych, zawierających soczewki (inkluzje) materiału gruboziarnistego. Materiał inkluzji charakteryzuje się niższą wartością ciśnienia wejścia powietrza niż materiał tła. Podczas infiltracji część powietrza zostaje zamknięta w inkluzjach, po całkowitym wypełnieniu wodą materiału tła. Z drugiej strony, drenaż inkluzji rozpoczyna się dopiero wtedy, gdy przekroczone zostanie ciśnienie wejścia...
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Can we rely on the pulse transit time - pressure relationship - models comparison
PublicationAn unobtrusive, noninvasive and continuous pressure measurement is invaluable however, still being under research and development. There are many attempts proposing an appropriate relationship between pulse pressure velocity and pressure. Fifteen different formulas, both theoretical and experimental, describing relation between blood pressure and crosssectional area of the vessel were examined. Using these formulas the relation...
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Pressure drop related to flow maldistribution in a model minichannel plate heat exchanger
PublicationThe paper describes the issues related to the pressure drop that accompanies the phenomenon of maldistribution of working fluid between the channels of a model minichannel plate heat exchanger. The research concerns a single exchanger's plate containing 51 (in every geometry) parallel rectangular minichannels of hydraulic diameters 461 µm, 571 µm, 750 µm and 823 µm. In addition, the more complex geometry has been investigated,...
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The effect of reduced pressure on carbon dioxide flow boiling heat transfer in minichannels
Publication. In the paper presented are the results of the study on the effect of reduced pressure on flow boiling heat transfer data in minichannels as well as conventional ones. That effect renders that most of heat transfer correlations fail to return appropriate results of predictions. Mostly they have been developed for the reduced pressures from the range 0.1-0.3. The special correction has been postulated to the in-house model of flow...
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Heat transfer and pressure drop characteristics of the silicone-based plate heat exchanger
PublicationThe paper presents an experimental investigation of a silicone based heat exchanger, with passive heat transfer intensification by means of surface enhancement. The main objective of this paper was to experimentally investigate the performance of a heat exchanger module with the enhanced surface. Heat transfer in the test section has been examined and described with precise measurements of thermal and flow conditions. Reported...
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An improved method for flow boiling heat transfer with account of the reduced pressure effect
PublicationIn the paper are presented the results using the authors own model to predict heat transfer coefficient during flow boiling. The model has been tested against a large selection of experimental data to investigate the sensitivity of the in-house developed model. In the work are presented the results of calculations obtained using the semi-empirical model on selected experimental flow boiling data of the refrigerants: R134a, R1234yf,...
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Impact of slow breathing on the blood pressure and subarachnoid space width oscillations in humans
PublicationThe aim of the study was to assess cardiac and respiratory blood pressure (BP) and subarachnoid space (SAS) width oscillations during the resting state for slow and fast breathing and breathing against inspiratory resistance. Experiments were performed on a group of 20 healthy volunteers (8 males and 12 females; age 25.3 ± 7.9 years; BMI = 22.1 ± 3.2 kg/m2). BP and heart rate (HR) were measured using continuous finger-pulse photoplethysmography....
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Identification of inertia, damping and stiffness parameters for low pressure steam turbine framework.
PublicationW pracy przedstawiono metodę identyfikacji masy tłumienia i sztywności kadłuba części niskoprężnej turbiny parowej 200MW.
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Influence of operating pressure on the durability of a satellite hydraulic motor supplied by rapeseed oil
PublicationThis article describes the results of a durability test of a hydraulic satellite motor supplied by rapeseed oil. The tests were carried out on a test stand in a power recuperation system. The tests of the motor were carried out at a constant shaft speed for three fixed pressure drops in the motor. This made it possible to demonstrate the influence of the motor operating pressure on the durability of the satellite mechanism. The...
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Application of atmospheric pressure microwave plasma source for hydrogen production from ethanol
PublicationIn contrast to conventional technologies of hydrogen production like water electrolysis or coal gasification we propose a method based on the atmospheric pressure microwave plasma. In this paper we present results of the experimental investigations of the hydrogen production from ethanol in the atmospheric pressure plasma generated in waveguidesupplied cylindrical type nozzleless microwave (915 MHz and 2.45 GHz) plasma source (MPS)....
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The influence of stainless steels microstructure evolution on the mechanical properties of pressure installation elements
PublicationIn this paper results of FEM analysis performed for pipe and 90o elbow, made of super duplex stainless steel, after precipitation of sigma phase (),were presented. Heat treatment conditions simulate accidental overheating that can occur in nuclear installations after cooling circulation fails. For initial and modified microstructure tensile test was performed and numerical description of work hardening curves was done. Verification...
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Experimental investigations on pressure drop during the condensation in flow of HFE7000 in vertical minichannel
PublicationIn the work presented in the paper authors focused attention on the issues of flow resistance and pressure drop during condensation in the flow. The case of the descending flow through a cylindrical single-channel of 2.3 mm inner diameter was carefully analyzed. In the course of investigations a new working fluid HFE 7000 has been scrutinised which has a strongly differing properties in comparison to the other fluids that are commonly...
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The influence of stainless steels microstructure evolution on the mechanical properties of pressure installation elements
PublicationIn this paper results of FEM analysis performed for pipe and 90o elbow, made of super duplex stainless steel, after precipitation of sigma phase (s), were presented. Heat treatment conditions simulate accidental overheating that can occur in nuclear installations after cooling circulation fails. For initial and modified microstructure tensile test was performed and numerical description of work hardening curves was done. Verification...