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Influence of Air Humidity on Transonic Flows with Weak Shock Waves

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Journal of Thermal Science 2020年第6期29卷 1551-1557页

作者： DYKAS Slawomir MAJKUT Miroslaw SMOLKA krystian Institute of Power Engineering and Turbomachinery Silesian University of TechnologyKonarskiego 18Gliwice 44-100Poland

The paper presents CFD results for the transonic flow of dry and moist air through a diffuser and a compressor *** both test geometries,*** Sajben transonic diffuser and the NASA Rotor 37,the air humidity impact on the structure of flows with weak shock waves was *** CFD simulations were performed by means of an in-house CFD code,which was the RANS-based modelling approach to compressible flow *** is shown that at high values of relative humidity,above 70%,the modelling of the transonic flow field with weak shock waves by means of the dry air model may produce wrong results.

关键词： dry air moist air transonic flow weak shock wave steam condensation

Chlorophyll extraction from leaves,needles and microalgae:A kinetic approach

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International Journal of Agricultural and Biological Engineering 2013年第2期6卷 107-115页

作者： krystian Miazek Stanislaw Ledakowicz Department of Bioprocess Engineering Technical University of Lodz90-924LodzPoland

Currently,there is a strong focus on industrial production of chlorophyll as a natural *** factors are required in the economically feasible process to make chlorophyll production:material with high pigment content and efficient extraction *** this work,extraction of chlorophyll from harvested black locust(Robinia pseudoacacia)leaves,Scots pine(Pinus sylvestris)needles,field sow thistle(Sonchus arvensis)leaves,and green microalga(Chlorella sp.)was *** highest pigment content was detected in Chlorella cells(4.46%)followed by black locust leaves(1.63%),sow thistle leaves(1.48%)and pine needles(0.38%).The chlorophyll extraction rate was the highest for black locust leaves(k=3.59 h^(-1)),sow thistle leaves(k=2.90 h^(-1))and Chlorella cells(k=2.80 h^(-1))with the use of methanol as a *** investigated materials,needles showed higher resistance for chlorophyll extraction(k=0.93 h^(-1))when compared to leaves and *** of extraction kinetic constant were much lower for all materials(0.22-1.12 h^(-1))in the case of using ethanol as a *** locust leaves and Chlorella cells were proved to be the most attractive materials for chlorophyll production.

关键词： chlorophyll extraction leaves needles microalgae kinetic approach

Losses Estimation in Transonic Wet Steam Flow through Linear Blade Cascade

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Journal of Thermal Science 2015年第2期24卷 109-116页

作者： Sawomir Dykas Mirosaw Majkut Micha Strozik krystian Smoka Institute of Power Engineering and Turbomachinery Silesian University of Technology

Experimental investigations of non-equilibrium spontaneous condensation in transonic steam flow were carried out in linear blade cascade. The linear cascade consists of the stator blades of the last stage of low pressure steam turbine. The applied experimental test section is a part of a small scale steam power plant located at Silesian University of Technology in Gliwice. The steam parameters at the test section inlet correspond to the real conditions in low pressure part of 200 MWe steam turbine. The losses in the cascade were estimated using measured static pressure and temperature behind the cascade and the total parameters at inlet. The static pressure measurements on the blade surface as well as the Schlieren pictures were used to assess the flow field in linear cascade of steam turbine stator blades.

关键词：蒸汽流量损失估计跨音速线性叶栅蒸汽涡轮机蒸汽动力装置叶片表面

Decreased serum essential and aromatic amino acids in patients with chronic pancreatitis

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World Journal of Gastroenterology 2010年第35期16卷 4422-4427页

作者： krystian Adrych Marian Smoczynski Magdalena Stojek Tomasz Sledzinski Ewa Slominska Elzbieta Goyke Ryszard Tomasz Smolenski Julian Swierczynski Department of Gastroenterology and Hepatology Medical University of Gdansk Department of Pharmaceutical Biochemistry Medical University of Gdansk Department of Biochemistry Medical University of Gdansk

AIM:To investigate the influence of chronic pancreatitis(CP) on serum concentrations of amino ***:Thirty-five male patients with alcoholic CP and 21 healthy male subjects were *** concentrations of amino acids were assayed by ionpair high-performance liquid chromatography with mass ***:Serum glutamate concentration was increased in CP patients as compared to *** contrast,serum concentrations of glutamine,histidine,tyrosine,proline,tryptophan and threonine were significantly decreased in CP patients.A trend towards decreasing concentrations of serum lysine,alanine,methionine and valine as well as for total serum amino acids was *** sum of aromatic and the sum of essential amino acid concentrations were significantly lower in CP patients than in ***:CP leads to decreased serum concentrations of several amino acids,such as essential and aromatic serum amino acids,most likely due to decreased exocrine function.

关键词： Amino acids Body mass index Chronic pancreatitis Maldigestion Malnutrition

In-depth analysis of the influence of bio-silica filler(Didymosphenia geminata frustules)on the properties of Mg matrix composites

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Journal of Magnesium and Alloys 2023年第8期11卷 2853-2871页

作者： Izabela B.Zgłobicka Anna Dobkowska Aleksandra Zielińska Ewa Borucinska Mirosław J.Kruszewski RafałZybała Tomasz Płociński Joanna Idaszek Jakub Jaroszewicz krystian Paradowski Bogusława Adamczyk-Cieślak Kostiantyn Nikiforow Bartosz Bucholc WojciechŚwięszkowski Krzysztof J.Kurzydłowski Faculty of Mechanical Engineering Bialystok University of TechnologyWiejska 45C15-351 BialystokPoland Faculty of Materials Science and Engineering Warsaw University of TechnologyWoloska 14102-507 WarsawPoland Lukasiewicz Research Network–Institute of Microelectronics and Photonics Al.Lotnikow 32/4602-668 WarsawPoland Institute of Physical Chemistry Polish Academy of Sciences Kasprzaka 44/5201-224 WarsawPoland Institute of Fundamental Technological Research Polish Academy of Sciences Pawinskiego 5B02-106WarsawPoland

A novel metal matrix composites(MMC)with Mg matrix reinforced with natural filler in the form of Didymosphenia geminata frustules(algae with distinctive siliceous shells)are presented in this *** plasma sintering(PPS)was used to manufacture Mg-based composites with 1,5 and 10 vol.%ceramic *** a reference,pure Mg was *** results show that the addition of 1 vol.%Didymosphenia geminata frustules to the Mg matrix increases its corrosion resistance by supporting passivation reactions,and do not affect the morphology of L929 *** of 5 vol.%the filler does not cause cytotoxic effects,but it supports microgalvanic reactions leading to the greater corrosion *** content than 5 vol.%the filler causes significant microgalvanic corrosion,as well as increases cytotoxicity due to the greater micro-galvanic effect of the composites containing 10 and 15 vol.%*** results of contact angle measurements show the hydrophilic character of the investigated materials,with slightly increase in numerical values with addition of amount of ceramic *** addition of Didymosphenia geminata frustules causes changes in a thermo-elastic properties such as mean apparent value of coefficient of thermal expansion(CTE)and thermal conductivity(λ).The addition of siliceous reinforcement resulted in a linear decrease of CTE and reduction in thermal conductivity over the entire temperature *** the increasing addition of Didymosphenia geminata frustules,an increase in strength with a decrease in compressive strain is *** all composites an increase in microhardness was *** results clearly indicate that filler in the form of Didymosphenia geminata frustules may significantly change the most important properties of pure Mg,indicating its wide potential in the application of Mg-based composites with a special focus on biomedical use.

关键词： Metal-matrix composites(MMCs) Pulse plasma sintering(PPS) Ceramic filler Microstructure Properties

Influence of KF substitution on the ferroelectric phase transition of lead titanate single crystals studied by Brillouin light scattering

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Journal of Advanced Dielectrics 2015年第2期5卷 47-52页

作者： Seonhyeop Shin Jae-Hyeon Ko Shinya Tsukada Yukikuni Akishige krystian Roleder Daniel Rytz Department of Physics Hallym UniversityHallymdaehakgil 39 ChuncheonGangwondo 200-702Republic of Korea Faculty of Education Shimane University Matsue-ShiShimane 690-8504Japan Institute of Physics University of Silesia ulica Uniwersytecka 4PL-40-007 KatowicePoland Forschungsinstitut für mineralische und metallische Werkstoffe Edelsteine/Edelmetalle GmbH(FEE)Struthstraβe 2 D-55743 Idar-ObersteinGermany

The elastic properties of KF-substituted perovskite lead titanate(PbTiO_(3))were investigated by dielectric measurements and Brillouin light *** ferroelectric phase transition occurred at substantially lower temperature due to KF substitution,which was attributed to the modification of the covalency in Pb–O and Ti–O *** longitudinal acoustic(LA)mode of KF-substituted PbTiO_(3) showed a frequency softening in the paraelectric phase,which was accompanied by increasing acoustic *** indicated that polarization fluctuations responsible for the acoustic anomalies were enhanced by KF substitution.

关键词： Lead titanate KF-substitution elastic property Brillouin scattering

Applicability of surface directional wells for upper Silesia Basin coal seams' drainage ahead of mining

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International Journal of Mining Science and Technology 2014年第3期24卷 353-362页

作者： Jura Bartlomiej Skiba Jacek Wierzbinski krystian Central Mining Institute Katowice

Methods of exploitation drainage, which is presently applied in polish hard coal mines in Upper Silesian Coal Basin(Poland), are not effective enough, high risk of methane hazard can be observed, and production capacity of the mining plant is not fully used. Methane hazard, which may occur during planned coal exploitation, is presented in this paper. Following parameters are taken into consideration in the forecasts: coal extraction parameters, geological and mining conditions, deposit's methane saturation degree and impact of coal exploitation on the degasification coefficient of the seams, which are under the influence of relaxation zone. This paper presents the results of the analysis aiming to verify applicability of drainage ahead of mining of the coal seams by using surface directional wells. Based on the collected data(coal seams' structural maps, profiles of the exploratory wells, geological cross-sections), the lab tests of drilling cores and direct wells' tests, static model of the deposit was constructed and suitable grid of directional wells from the surface was designed. Comparison of forecasted methane emission volume between the two methods is investigated. The results indicated the necessity of performing appropriate deposit's stimulations in order to increase effectiveness of drainage ahead of mining.

关键词：定向井煤层西亚水提采矿甲烷排放量煤炭开采实验室测试

Sensitivity Analysis of a 50+ Coal-Fired Power Unit Efficiency

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Journal of Power and Energy Engineering 2015年第12期3卷 19-31页

作者： Katarzyna Stepczyńska-Drygas Slawomir Dykas krystian Smolka Institute of Power Engineering and Turbomachinery Silesian University of TechnologyGliwicePoland

The coal-fired power unit integration with a CO2 capture and compression installation involves a considerable rise in the costs of electricity generation. Therefore, there is a need for a continuous search for methods of improving the electricity generation efficiency in steam power plants. One technology which is especially promising is the advanced ultra-supercritical (A-USC) power unit. Apart from steam parameters upstream the turbine, the overall efficiency also depends on the efficiency values of individual elements of the plant and the size of energy consumption of the process of CO2 sequestration from the boiler flue gases. These problems are considered herein to emphasize that without specifying the efficiency values of the power plant main elements the information concerning its electricity generation efficiency is incomplete. This paper presents the influence of the efficiency of individual elements of the power plant on its electricity generation efficiency. The lack of information of the efficiencies of the power plant individual elements, by presenting its overall efficiency, may lead to the false conclusions.

关键词： Sensitivity Analysis A-USC Power Unit Efficiency CO_(2) Capture

An Attempt to Evaluate the Cycloidal Rotor Fan Performance

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Open Journal of Fluid Dynamics 2019年第4期9卷 292-302页

作者： Tomasz Stasko Slawomir Dykas Miroslaw Majkut krystian Smolka Silesian University of Technology Institute of Power Engineering and Turbomachinery Gliwice Poland

In this work, the cycloidal rotor fan (CRF) performance was estimated by means of a numerical method based on Unsteady Reynolds Averaged Navier-Stokes equations (URANS). The fan with a cycloidal rotor belongs to the positive displacement machines of the rotary type. The numerical algorithm for simulation of the flow in the cycloidal rotor as well as postprocessing of the CFD results was prepared using Ansys CFX CEL. The methodology for the assessment of the CRF performance was proposed and verified. It was found out that the CRF performance strongly depends on the shape of the profile of the applied rotor blade. The NACA 0012 and CLARK Y profiles were tested for the same CRF structure and flow conditions. Also, the crucial importance for the CRF performance has the range of the blade pitch angle change.

关键词： Cycloidal Rotor Computational Fluid Dynamics Fan Performance