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Experimental Investigation of Effects of Reynolds Number and Incidence Angle on Secondary Flow within a Linear Blade Cascade

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Journal of Thermal Science 2021年第6期30卷 2122-2136页

作者： FLÍDR Erik JELÍnek Tomáš KLADRUBSKÝMilan Laboratory of High Speed Aerodynamics Czech Aerospace Research CenterBeranovych 130Prague 19905Czech Republic

The kinetic energy loss and the secondary loss downstream of a high turning nozzle cascade were *** of the incidence angle(i=-25°,0°and 25°)and Reynolds number(Re_(2,is)=0.8×10^(5),1.2×10^(5),2.5×10^(5) and 4.5×10^(5))were studied on two cascade configurations defined by different pitch to chord ratio(t/c=0.6 and 0.9),*** at the cascade inlet were performed by means of Preston tube,while at the cascade outlet by means of miniature pyramid five-hole pressure *** effect of studied parameters on the flow field at the cascade outlet was shown by the distribution of the kinetic energy loss,secondary loss,mix-out loss and streamwise vorticity.

关键词： linear blade cascade secondary loss pressure measurement

Spectral properties and identification of aerostatic bearings

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Acta Mechanica Sinica 2011年第1期27卷 63-67页

作者： Jan Kozánek Ladislav Pust Institute of Thermomechanics AS CR

Modified rotor kit Bently Nevada was used for dynamic characteristics measurements of new developed aerostatic *** model of these bearings is considered as *** was identified with the help of harmonic force excitation independently from the speed of journal *** stiffness and damping matrices were identified for different air inlet *** calculated spectral properties allow to determine the stability boundary for suitable variation of model parameters.

关键词： Aerostatic bearing · Identification · Stiffness · Damping coefficients

Geomorphic evidence of ancient catastrophic flow type landslides in the mid-mountain ridges of the Western Flysch Carpathian Mountains(Czech Republic)

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International Journal of Sediment Research 2009年第1期24卷 88-98页

作者： T. Pnek J. HRADECKY K. ILHN Assoc. University of Ostrava Faculty of Science Department of Physical Geography and Geoecology Chittussiho 10 71000 Ostrava Czech Republic University of Ostrava Faculty of Science Department of Physical Geography and Geoecology Chittussiho 10 71000 Ostrava Czech Republic

Ancient flow type landslides are relatively frequent fossil forms of the relief in mid-mountain conditions of the Czech Carpathian Mountains. Sixty rather distinctive displays of debris flows,rock avalanches,and debris avalanches have been mapped in the uppermost part of the territory. Unlike contemporary sporadic and low volume debris flows,ancient(Pleistocene and Lower Holocene) accumulations are a few orders of magnitude more extensive and were of considerable geomorphologic significance in forming the steep sections of mountain valleys and slopes. This geomorphic pattern does not hold for flow type slides,the source of which is material released as a consequence of numerous deep-seated landslides. Due to deep disruption of slopes,a few high-magnitude flow type landslides(e.g.,rock avalanches),quite rare in flysch mid-mountain conditions,also occurred in the Late Holocene.

关键词： Debris flows Rock avalanches Deep-seated landslides Flysch Western Carpathian Mountains

Thermostability of montmorillonitic clays

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China Foundry 2014年第3期11卷 201-207页

作者： Petr Jelínek Stanislaw M.Dobosz Jaroslav Beňo Katarzyna Major-Gabrys VSB–Technical University of Ostrava Faculty of Metallurgy and Material Engineering Department of Metallurgy and Foundry Engineering Czech Republic AGH University of Science and Technology Faculty of Foundry Engineering Department of Moulding Materials Mould Technology and Foundry of Non-ferrous Metals Al. Mickiewicza 30 30-059 Krakow Poland

Bentonite is one of the most widespread used clays connected with various applications. In the case of foundry technology, bentonite is primarily used as a binder for mold manufacture. Thermal stability of bentonites is a natural property of clay minerals and it depends on the genesis, source and chemical composition of the clay. This property is also closely connected to bentonite structure. According to DTA analysis if only one peak of dehydroxylation is observed(about 600 oC), the cis- isomerism of bentonite is expected, while two peaks of de-hydroxylation(about 550 and 850 oC) are expected in the trans- one. In this overview, the bentonite structure, the water – bentonite interaction and the swelling behavior of bentonite in connection with the general technological properties of bentonite molding mixture are summarized. Further, various types of methods for determination of bentonite thermostability are discussed, including instrumental analytical methods as well as methods that employ evaluation of various technological properties of bentonite binders and/or bentonite molding mixtures.

关键词： bentonite thermostability binder clay

Enhancement of the ‘tractor-beam’ pulling force on an optically bound structure

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Light(Science & Applications) 2017年第1期6卷 136-141页

作者： Jana Damková Lukáš Chvátal Jan Ježek Jindřich Oulehla Oto Brzobohatý Pavel Zemánek Institute of Scientific Instruments of the CAS v.v.i.Královopolská147Brno 61264Czech Republic

Recently,increasing attention has been devoted to mastering a new technique of optical delivery of micro-objects tractorbeam’1–*** beams have uniform intensity profiles along their propagation direction and can exert a negative force that,in contrast to the familiar pushing force associated with radiation pressure,pulls the scatterer toward the light *** was experimentally observed that under certain circumstances,the pulling force can be significantly enhanced6 if a non-spherical scatterer,for example,a linear chain of optically bound objects10–12,is optically *** we demonstrate that motion of two optically bound objects in a tractor beam strongly depends on theirs mutual distance and spatial *** configuration-dependent optical forces add extra flexibility to our ability to control matter with *** these interactions opens the door to new applications involving the formation,sorting or delivery of colloidal self-organized structures.

关键词： beam scatter mutual

Transgenic plum Prunus domestica L., clone C5(cv. Honey Sweet) for protection against sharka disease

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Journal of Integrative Agriculture 2017年第3期16卷 516-522页

作者： Jaroslav Polák Jiban K Kundu Boris Krska Eva Beoni Petr Komínek Jitka Pívalová Jana Jarosová Division of Crop Protecting and Plant Health Crop Research Institute Prague 16106 Czech Republic Horticultural Faculty Lednice Mendel University Brno Lednice 69144 Czech Republic

Sharka caused by Plum pox virus（PPV）is the most harmful disease of stone fruits in Europe and elsewhere in the *** is no highly PPV resistant cultivar of *** approach has led to the development of resistance through genetic *** this study,we evaluated a transgenic plum Prunus domestica L.,clone C5（*** Sweet）,where the PPV resistance is based on RNA interference（RNAi）.Resistance in C5 plums has been evaluated for PPV,Prune dwarf virus（PDV）,and Apple chlorotic leaf spot virus（ACLSV）in a regulated field trial in the Czech Republic for 12 years（2002–2013）.Even under high and permanent infection pressure introduced through graft inoculation of the viruses,PPV has been detected in C5 trees only in several leaves situated close to the point of inoculum grafting in the first nine *** symptoms of PPV disappeared year by *** PPV symptoms were observed in the last three years and results of ELISA detection were *** results were obtained,when RT-PCR was used for PPV *** natural infection of PPV by aphids was recorded in C5 plums,even if PPV infected plants were growing in the same experimental field in close ***-infections of PPV with PDV and/or ACLSV had practically no influence on stability of resistance in C5 *** years of field testing in the Czech Republic clearly demonstrated the high level of resistance of C5 either to PPV infection by graft inoculation or natural infection through aphid vectors.

关键词： PPV C5 resistance transgenic plum HoneySweet

EFFECT OF ARTIFICIAL WEATHERING AND TEMPERATURE CYCLING ON THE ADHESION STRENGTH OF WATERBORNE ACRYLATE COATING SYSTEMS USED FOR WOODEN WINDOWS

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Journal of Green Building 2020年第1期15卷 3-14页

作者： Šimůnková Kristýna Hýsek Štěpán Oberhofnerová Eliška Pánek Miloš Fidan Hakan Faculty of Forestry and Wood Sciences Czech University of Life Sciences in PragueKamycka 129Prague 16500Czech Republic

The adhesion of coatings to wood is important for their long-term *** this study,the adhesion strength of water-based acrylate coatings used for wooden windows after exposure to artificial weathering(AW)and temperature cycling(TC)was *** analysis of the adhesion quality of coatings was performed via a pull-off test and failure *** 3-layered and 4-layered white and brown acrylate dispersions from six different producers were compared and the effect of coating thickness on adhesion strength was *** adhesion strength values proved to be very *** AW,the adhesion strength and its variability increased for all the *** had no statistically significant effect on the adhesion strength *** coating systems were initially characterized by lower adhesion strength,but after AW and TC,they reached higher adhesion strength values than brown *** overall highest adhesion after AW and TC was recorded for the coatings based on alkyd-acrylate hybrid basis(Producer 3),while the lowest adhesion variability after AW was measured for one type of tested acrylate coating(Producer 4).The effect of different layering on adhesion strength was not demonstrated in this study.

关键词： acrylate coatings adhesion strength artificial weathering coating thickness pull-off test temperature cycling

Identification of altitude profiles in 3D geovisualizations:the role of interaction and spatial abilities

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International Journal of Digital Earth 2019年第2期12卷 156-172页

作者： Petr Kubíček Čeněk Šašinka Zdeněk Stachoň Lukáš Herman Vojtěch Juřík Tomáš Urbánek Jiří Chmelík Department of Geography Faculty of ScienceMasaryk UniversityBrnoCzech Republic HUME Lab Faculty of ArtsMasaryk UniversityBrnoCzech Republic Department of Psychology Faculty of ArtsMasaryk UniversityBrnoCzech Republic Department of Computer Graphics and Design Faculty of InformaticsMasaryk UniversityBrnoCzech Republic

Three-dimensional geovisualizations are currently pushed both by technological development and by the demands of experts in various applied *** the presented empirical study,we compared the features of real 3D(stereoscopic)versus pseudo 3D(monoscopic)geovisualizations in static and interactive digital elevation *** tested 39 high-school students in their ability to identify the correct terrain profile from digital elevation ***’performance was recorded and further analysed with respect to their spatial abilities,which were measured by a psychological mental rotation test and think aloud *** results of the study indicated that the influence of the type of 3D visualization(monoscopic/stereoscopic)on the performance of the users is not clear,the level of navigational interactivity has significant influence on the usability of a particular 3D visualization,and finally no influences of the spatial abilities on the performance of the user within the 3D environment were identified.

关键词： 3D geovisualizations stereoscopic and monoscopic 3D vision spatial abilities level of navigational interactivity

Mortality of therapeutic fish Garra rufa caused by Aeromonas sobria

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Asian Pacific Journal of Tropical Biomedicine 2012年第2期2卷 85-87页

作者： Juraj Majtán Jaroslav erny Alena Ofúkaná Peter Taká Milan Kozánek Institute of Zoology Slovak Academy of SciencesDubravska cesta 984 506 Bratislava Department of Microbiology Faculty of MedicineSlovak Medical UniversityLimbova 1 283 303Bratislava

Objective:To investigate a case of mass mortality of Garra rufa(***)from a fish hatchery farm in ***:Causative bacterial agent was swabbing out of affected fish skin area and subsequently identified using commercial test *** susceptibility was determined by the disk diffusion ***:Infected *** was characterized by abnormal swimming behaviour,bleeding of skin lesions and local *** of using recommended aquatic antibiotic treatment no improvement was achieved and Aeromonas sobria{***)was identified as a causative agent of fish *** to massive fish mortality,antibiotic susceptibility of pure isolated culture of *** was evaluated employing eight antibiotics against human *** was resistant only against one antibiotic,namely ***:These results indicate that *** can act as a primary pathogen of *** and may be a potential risk factor for immunodeficient or immunoincompetent patients during the ichthyotherapy.

关键词： Garra rufa lehthyotherapy Aeromonas sobria antibiotic treatment antibiotic susceptibility