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Search results for: FRICTIONAL PRESSURE DROP
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Znajomość własnego ciśnienia tętniczego i rozpowszechnienie nadciśnienia tętniczego w populacji wiejskiej - Program Kiełpino = The cognizance of patient's own blood pressure values and the hypertension prevalence among rural population - Kiełpino program
PublicationNadciśnienie tętnicze jest jedną z najczęstszych chorób przewlekłych występujących w Polsce. Nieleczone nadciśnienie tętnicze prowadzi do licznych powikłań, jest przyczyna przedwczesnej umieralności, wpływa na pogorszenie komfortu życia pacjenta i zwiększa koszty leczenia. Ocena znajomości własnego ciśnienia tętniczego krwi oraz rozpowszechnienia nadciśnienia tętniczego u pacjentów w wiejskiej praktyce lekarza rodzinnego - jest...
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In-situ generation of Ag, Cd, Hg, In, Pb, Tl and Zn volatile species by flowing liquid anode atmospheric pressure glow discharge operated in gaseous jet mode – Evaluation of excitation processes and analytical performance
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Three-dimensional numerical investigation of hybrid nanofluids in chain microchannel under electrohydrodynamic actuator
PublicationEnergy efficiency enhancement methods have received considerable attentionwithin the industry and scientific community, owing to the rising concern ofglobal energy sustainability. The present article attempts to scrutinize the effectsof electrohydrodynamics and nanofluids on the rate of heat transfer and fluidflow in the 3-D chain microchannels. Improved heat exchangers (e.g., chainmicrochannel) would have a key role in increasing...
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Wpływ warunków ciśnieniowej filtracji na przebieg biologicznego usuwania azotu amonowego z wody w procesie nitryfikacji = Effect of pressure filtration conditions on nitrification process used for ammonia nitrogen removal from water
PublicationW pracy przedstawiono wyniki badań laboratoryjnych nad wpływem podwyższonego, zmiennego ciśnienia (do 0,8 MPa) na przebieg usuwania azotu amonowego z wody na nitryfikacyjnym złożu filtracyjnym. Wykazano, że ani podwyższone ciśnienie, ani jego zmiany nie wpływają hamująco na przebieg procesów nitryfikacji. Stwierdzono pozytywny wpływ płukania filtrów biologicznych na usuwanie azotu amonowego z wody.
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Experimental and analytical analysis of punching shear in flat slabs supported on column topped with concrete head
PublicationAn experimental laboraatory test of the two series of slab-column elements topped with drop panels of varying sizes is described in this paper. The scope of the paper is to investigate the influence of the drop panel size and stiffness on the behaviour of the connection between the flat slab and the column topped by the concrete head. The impact of the head size and stiffness is analysed analytically and experimentally. The experimental...
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Marine Fuel Sulphur Limit Impact on Air Pollution
PublicationThe article presents calculation of Sulphur oxides percentage drop rate in marine industry recorded after 01.01.2020 when new limits, provided by International Maritime Organizations legislation, became effective. Ships’ SOx global emission was estimated and compared between 4th quarter 2019 and 1st quarter 2020. For more accurate estimation 3 seaside cities with big harbors were selected for statistical analysis. Noticeable...
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Research of Emergency Modes of Wind Power Plants Using Computer Simulation
PublicationThe aim of this study is to investigate changes in the wind power plant energy production parameters under the conditions of sudden wind changes and voltage drop. To achieve these goals, a simulation of operation of wind power plants was performed. Twelve wind turbines with variable rotational speed equipped with a Fuhrländer FL 2500/104 asynchronous double-fed induction generator (DFIG) were used, each with an installed capacity...
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Entire fracture surface topography parameters for fatigue life assessment of 10H2M steel
PublicationIn this paper, the entire fracture surface approach was used to assess an effect of 280,000 h of exploitation under internal pressure of 2.9 MPa and high temperature of 540 °C on the fatigue response of 10H2M (10CrMo9–10) power engineering steel. The mechanical testing was carried out on the hourglass specimens produced from the as-received, unused pipeline and the same material after long-time exploitation. The uniaxial tensile...
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Applying response surface method to optimize the performance of a divergent-chimney solar power plant
PublicationOne of the effective tools to generate electricity from solar energy is Divergent-chimney solar power plant (DSPP). Divergent and cylindrical chimneys of solar power plants have different performances considering turbine pressure drop ratio (ft). For the first time, the divergent angle (DA) and solar radiation (SR) interaction effects on 〖ft〗_opt are discussed through applying the Computational Fluid Dynamics (CFD) and Response...
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Effects of FSW Tool Plunge Depth on Properties of an Al-Mg-Si Alloy T-Joint: Thermomechanical Modeling and Experimental Evaluation
PublicationOne of the main challenging issues in friction stir welding (FSW) of stiffened structures is maximizing skin and flange mixing. Among the various parameters in FSW that can affect the quality of mixing between skin and flange is tool plunge depth (TPD). In this research, the effects of TPD during FSW of an Al-Mg-Si alloy T-joint are investigated. The computational fluid dynamics (CFD) method can help understand TPD effects on FSW...
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Influence of pH and low-molecular weight organic compounds in solution on selected spectroscopic and analytical parameters of flowing liquid anode atmospheric pressure glow discharge (FLA-APGD) for the optical emission spectrometric (OES) determination of Ag, Cd, and Pb
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Numerical analysis of high temperature minichannel heat exchanger for recuperative microturbine system
PublicationConsidering the development of energy sector, distributed small-scale power generation, e.g., gas micro-CHP, is attracting considerable interest. In such installations, the heat exchanger is one of the key components possessing a significant influence on overall performance. Most studies concentrate on units operating below 900C, which do not fulfil the requirements of gas micro-CHP. Therefore, there remains a challenge to design...
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Experimental investigation of heat transfer enhancement in straight and U-bend double-pipe heat exchanger with wire insert
PublicationIn this paper, the possibility of heat transfer enhancement in the U-bend exchanger was presented. Experimental research has been carried out for four individual heat exchanger constructions i.e. plain tube in tube, turbulized tube in tube, plain U-bend and U-bend with turbulator. Also, heat transfer experiments for various boundary conditions were performed to obtain reference values. In case of U-bend exchanger with and without...
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Reply to the ‘Comment on “Spectroscopic properties and location of the Ce3+ energy levels in Y3Al2Ga3O12 and Y3Ga5O12 at ambient and high hydrostatic pressure”’ by Y. Wang, M. Głowacki, M. Berkowski, A. Kamińska and A. Suchocki, Phys. Chem. Chem. Phys., 2019, 21, DOI: 10.1039/C8CP06154H
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Study of Slip Effects in Reverse Roll Coating Process Using Non-Isothermal Couple Stress Fluid
PublicationThe non-isothermal couple stress fluid inside a reverse roll coating geometry is considered. The slip condition is considered at the surfaces of the rolls. To develop the flow equations, the mathematical modelling is performed using conservation of momentum, mass, and energy. The LAT (lubrication approximation theory) is employed to simplify the equations. The closed form solution for velocity, temperature, and pressure gradient...
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Metodyka badań rozwojowych nowego typu silników i pomp satelitowych
PublicationResearch and development of new type satellite motors and satellite pumps SM with small geometrical displacement, from 5 to 73 cm3/rev, has been conducted in cooperation with Stosowanie Maszyn company from Katowice (manufacturer of motors and pump SM). The improvement of construction of those machines, especially construction of axial compensation and construction of fluid distribution channels have been the main problem of research...
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Compact High Efficiency and Zero-Emission Gas-Fired Power Plant with Oxy-Combustion and Carbon Capture
PublicationReduction of greenhouse gases emissions is a key challenge for the power generation industry, requiring the implementation of new designs and methods of electricity generation. This article presents a design solution for a novel thermodynamic cycle with two new devices—namely, a wet combustion chamber and a spray-ejector condenser. In the proposed cycle, high temperature occurs in the combustion chamber because of fuel combustion...
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Numerical Study on Mitigation of Flow Maldistribution in Parallel Microchannel Heat Sink: Channels Variable Width Versus Variable Height Approach
PublicationMicrochannel heat sink on one hand enjoys benefits of intensified several folds heat transfer performance but on the other hand has to suffer aggravated form of trifling limitations associated with imperfect hydrodynamics and heat transfer behavior. Flow maldistribution is one of such limitation that exaggerates temperature nonuniformity across parallel microchannels leading to increase in maximum base temperature. Recently, variable...
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RADIATION OF HIGH INTENSITY SOUND BY CIRCULAR DISC BY MEANS OF THE NUMERICAL METHOD
PublicationThe main goal of this paper is to find sound pressure distribution radiated by the circular piezoelectric disc that vibrates with the finite amplitude. There has been presented the pressure distribution close to the radiating surface. Also it is shown the sound pressure distribution in the 3D form. The mathematic modeling was carried out on the base of the nonlinear acoustic equation with the proper boundary condition. The axial...
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Zamienniki ''serwisowe'' czynnika R 22. Część I
PublicationW pierwszej części artykułu zestawiono dostępne na rynku czynniki chłodnicze przeznaczone do zastąpienia czynnika R 22 w istniejących układach chłodniczych bez konieczności przezbrajania instalacji. Wskazano miejsce tych mieszanin typu ''drop-in'' w technice chłodniczej. Podano skład i zasadnicze przeznaczenie poszczególnych płynów.
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WSPÓŁCZESNE OCHŁODZENIE REJONU SZETLANDÓW POŁUDNIOWYCH I PÓŁNOCO-ZACHODNICH KRAŃCÓW PÓŁWYSPU ANTARKTYCZNEGO
PublicationThe paper discusses changes of hydro-climatic conditions occurring in the South Shetland Islands and in NW parts of the Antarctic Peninsula in the 1979–2016 years period. These changes are important for evaluation of the transformation of marine and coastal ecosystems. The general feature of these changes was a transition from the strong warming phase to the cooling phase, which took place around the year 2000. The paper presents...
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Nanoindentation tests titanium alloy Ti-6Al-4V after interference laser treatment
PublicationThe study aimed was to assess selected mechanical properties of surface layers obtained after interference laser treatment – DLIL of titanium alloy Ti-6Al-4V used for implants. The samples were melted in still air at room temperature, for this purpose Nd:YAG laser was used, the number of laser shots was variable. Next, nanoindentation tests were performed, based on which Young’s modulus and nanohardness in the obtained surface...
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The Influence of Loop Heat Pipe Evaporator Porous Structure Parameters and Charge on Its Effectiveness for Ethanol and Water as Working Fluids
PublicationAbstract: This paper presents the results of experiments carried out on a specially designed experimental rig designed for the study of capillary pressure generated in the Loop Heat Pipe (LHP) evaporator. The commercially available porous structure made of sintered stainless steel constitutes the wick. Three different geometries of the porous wicks were tested, featuring the pore radius of 1, 3 and 7 um. Ethanol and water as two...
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On design and analysis of flow characteristics of the last stage of gas-steam turbine
PublicationResearch regarding blade design and analysis of flow have been conducted for over a century. Meanwhile new concepts and design approaches were created and improved. Advancements in information technologies allowed to introduce computational fluid dynamics (CFD) and computational flow mechanics (CFM). Currently a combination of mentioned methods is used for design of turbine blades. These methods enabled us to improve flow efficiency...
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THERMODYNAMIC ANALYSIS OF A GENERATION IV SCWR NUCLEAR POWER PLANT CYCLE
PublicationThis article presents a flow and thermodynamic analysis of a Generation IV nuclear cycle. An SCWR (Supercritical water reactor) is a high temperature and high pressure reactor that uses water at a temperature above its thermodynamic critical point as the working fluid. The cycle used for the calculations consists of one interstage superheater and 7 regenerative heat exchangers. Division pressure was optimized in view of the cycle efficiency,...
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Effect of Pin Shape on Thermal History of Aluminum-Steel Friction Stir Welded Joint: Computational Fluid Dynamic Modeling and Validation
PublicationThis article studied the effects of pin angle on heat generation and temperature distribution during friction stir welding (FSW) of AA1100 aluminum alloy and St-14 low carbon steel. A validated computational fluid dynamics (CFD) model was implemented to simulate the FSW process. Scanning electron microscopy (SEM) was employed in order to investigate internal materials’ flow. Simulation results revealed that the mechanical work...
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Initial Investigation of Wave Interactions During Simultaneous Valve Closures in Hydraulic Piping Systems
PublicationThe effects of interference of pressure waves in simple piping systems were studied. A freeware computer code Allievi developed at the University of Valencia was used to simulate dynamic waveforms in simple and complex networks. The tests were carried out according to three scenarios. No pressure increases significantly exceeding the Joukowsky pressure in simple cases were noticed. When the effects of the simultaneous closing of...
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Effect of Some Sulphur Additives on The Degradation of 9Cr-1Mo Steel After Its 10 Years Service in The CCR Platforming Unit
PublicationThe work shows the results of the tests of 9Cr-1Mo steel, which was for 10 years operated in the CCR platforming unit in Group Lotos SA in Gdańsk, and then in the laboratory was sulphidised during 166 h at a temperature of 600 °C. Sulphidation was performed in a mixture of H2-H2S gases at the vapour pressure of sulphur 4.1·10-14 atm, so the order of magnitude of vapour pressure was less than that of the dissociation pressure of...
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Exergy analysis of a negative CO2 emission gas power plant based on water oxy-combustion of syngas from sewage sludge gasification and CCS
PublicationA power cycle with water-injected oxy-combustion (water cycle) is investigated by exergy analysis. It is fueled with syngas (aka. producer gas) from gasification of sewage sludge. The cycle is equipped with a spray-ejector condenser (SEC). CO2 is separated and compressed for transportation and storage. The net delivered electric power is 31% of the fuel exergy. The task efficiency is 39% when the flue gas bleed to gasification...
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Need for multiple risk reduction strategies in clinical trials enrolling high risk patients - FOURIER investigating PCSK-9 inhibitor to lower cholesterol revisited
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Masked arterial hypertension in a 64-year-old man with primary aldosteronism
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Prevalence and distribution of left ventricular diastolic dysfunction in treated patients with long-lasting hypertension
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2018 Practice guidelines for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension
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Women’s health, cardiovascular risk and hypertension: the perspective still needs to improve
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The PARAGON Heart Failure trial – ongoing investigation of the angiotensin receptor antagonist/neprilysin inhibitor sacubitril/valsartan in heart failure patients with hypertension and preserved ejection fraction
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New data on antihypertensive drugs and risk of cancer: should we worry?
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Treatment strategies for comorbid conditions lower residual risk in patients with treated hypertension: FOURIER and other randomized outcome trials
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2013 ESH/ESC Practice Guidelines for the Management of Arterial Hypertension
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2018 Practice guidelines for the management of arterial hypertension of the European Society of Hypertension
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Novel approaches: targeting sympathetic outflow in the carotid sinus
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Peter Meredith
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The INTERSTROKE Study: hypertension is by far the most important modifiable risk factor for stroke
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Hypertension Management by Practice Guidelines
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Hypertension and cochlear hearing loss
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The Health Outcomes Prevention and Evaluation 4 (HOPE 4) project: A successful community-based intervention to lower cardiovascular risk in people with hypertension
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The PARAGON-Heart failure trial – another disappointment for heart failure patients with hypertension and preserved ejection fraction
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Insufficiency of the zona glomerulosa of the adrenal cortex and progressive kidney insufficiency following unilateral adrenalectomy – case report and discussion
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HOPE-3, SPRINT, VALUE and a meta-analysis of trials in patients with diabetes support treatment of hypertension to a target below 140 mmHg
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How to measure retinal microperfusion in patients with arterial hypertension
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TIME to face the reality about evening dosing of antihypertensive drugs in hypertension
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