Limpar
128 resultados

Acesso aberto

Tipo do recurso

Tipo de base de dados

Ano de criação

Produção nacional

Revisado por pares

Áreas

Idioma

Editores

Artigo Acesso aberto Revisado por pares

Kateřina Stejskalová, David Bujdoš, Lukáš Procházka, Bedřich Smetana, Simona Zlá, Jiří Teslík,

One of the solutions for overheating the interior in the summer without increasing energy consumption is the integration of phase change material (PCM) into interior plasters. However, adding PCM to plasters deteriorates their properties and thus their usability. The aim of this paper is to determine how the microencapsulated PCM affects the mechanical, thermal, and fire properties of plasters and how much PCM can be added to the plaster. Two sets of samples were prepared: in set S, part of the aggregate ...

Tópico(s): Adsorption and Cooling Systems

2022 - Multidisciplinary Digital Publishing Institute | Materials

Artigo Revisado por pares

Radim Škuta, Vlastimil Matějka, Kryštof Foniok, Aneta Smýkalová, Daniel Cvejn, Roman Gabor, Martin Kormunda, Bedřich Smetana, Vlastimil Novák, Petr Praus,

The synthesis of P-doped graphitic carbon nitride (PCN) by in situ doping via co-pyrolysis of melamine and hexachlorocyclotriphosphazene (HCCP) is being investigated. The amount of HCCP varies between 2 and 40 wt% and the results show continuous enrichment of graphitic carbon nitride (CN) by phosphorus. The detailed characterization of prepared samples leads to the proposition of the occurrence of phosphorus in synthesized samples as well as to the proposition of a P-doping mechanism. The results of ...

Tópico(s): Copper-based nanomaterials and applications

2021 - Elsevier BV | Applied Surface Science

Artigo Revisado por pares

Petr Praus, Aneta Smýkalová, Kryštof Foniok, Vlastimil Matějka, Martin Kormunda, Bedřich Smetana, Daniel Cvejn,

Two types of bulk graphitic carbon nitrides (CN) were synthetized by heating melamine at 550 °C for 4 h in the air (CN/air) and nitrogen (CN/N2) atmosphere for us to find the effect of present oxygen on their properties. Bulk CN was exfoliated by further heating at 500 °C for 1–3 h in air and nitrogen as well. The obtained materials were studied in terms of structural, textural and physico-chemical properties including photocatalytic activity. The CN/air materials contained less oxygen (2.3–5.0 wt%) than ...

Tópico(s): Gas Sensing Nanomaterials and Sensors

2020 - Elsevier BV | Applied Surface Science

Artigo Acesso aberto Revisado por pares

Marta Valášková, Zdeněk Klika, Boris Novosad, Bedřich Smetana,

Kaolin is most often used as traditional raw material in ceramic industry. The purpose of the study was to obtain understanding of the structural and chemical variability of cordierite ceramics influenced by chemical and mineralogical properties of six raw kaolins taken from different localities when they are applied in ceramics mixtures with vermiculite and sintered up to 1300 °C. The X-ray diffraction and simultaneous thermogravimetric and differential thermal analysis were used to identify and ...

Tópico(s): Concrete and Cement Materials Research

2019 - Multidisciplinary Digital Publishing Institute | Materials

Artigo Revisado por pares

Philipp Sauerschnig, A. Grytsiv, Jan Vřešťál, V.V. Romaka, Bedřich Smetana, Gerald Giester, E. Bauer, P. Rogl,

Tópico(s): Electronic Packaging and Soldering Technologies

2017 - Elsevier BV | Journal of Alloys and Compounds

Artigo Revisado por pares

Aleš Kalup, Bedřich Smetana, Monika Kawuloková, Simona Zlá, Hana Francová, Petr Dostál, Kateřina Waloszková, Lenka Waloszková, Jana Dobrovská,

Tópico(s): Metallurgical and Alloy Processes

2016 - Springer Science+Business Media | Journal of Thermal Analysis and Calorimetry

Artigo Revisado por pares

Marta Valášková, J. Zdrálková, Gražyna Simha Martynková, Bedřich Smetana, Jozef Vlček, Soňa Študentová,

The cordierite/steatite ceramics were prepared from the pre-ceramic clay mineral mixtures containing talc, kaolinite and unconventionally used vermiculite. The aim was to characterize cordierite/steatite ceramics in relation to the vermiculites in the pre-ceramic mixtures and compare the influence of their sintering, loosely in crucibles and pressed into pellets. Quantitative X-ray diffraction (XRD) analysis revealed approximately a 5 vol% lower content of indialite (IND) sintered in pellets than ...

Tópico(s): Concrete and Cement Materials Research

2014 - Elsevier BV | Ceramics International

Artigo Revisado por pares

Kelly St. Pierre,

Abstract Scholars have long framed similarities between Bedřich Smetana's “Vyšehrad” (the first movement of Má vlast) and Zdeněk Fibich's symphonic poem Záboj, Slavoj, and Luděk as a threat to Smetana' ...

Tópico(s): Musicology and Musical Analysis

2013 - University of California Press | 19th-Century Music

Artigo Revisado por pares

Marta Valášková, Jonáš Tokarský, Marianna Hundáková, J. Zdrálková, Bedřich Smetana,

The Zr4 +–vermiculites were studied in their new role of the zircon precursor in the clay minerals mixtures which were prepared for firing of the zircon–cordierite nanocomposites. Currently there is a lack of data available about the structure of Zr4 +–vermiculites, on which this study was performed. The modeling of the arrangement of interlayer material in the Zr4 +–vermiculite led to new findings that water molecules are attracted more strongly by Mg2 + cations than by Zr-tetrameric cations, and that ...

Tópico(s): Layered Double Hydroxides Synthesis and Applications

2013 - Elsevier BV | Applied Clay Science

Artigo Acesso aberto Revisado por pares

Bedřich Smetana, Simona Zlá, Aleš Kroupa, Monika Žaludová, Jaromír Drápala, Rostislav Burkovič, Daniel PETLÁK,

The Sn–Zn–Al system was studied in connection with the possible substitution of lead-based solders for temperatures up to 350 °C. Ternary alloys with up to 3 wt% of aluminium were prepared. The investigated alloys lie close to the monovariant line (eutectic valley) of the Sn–Zn–Al system. The temperatures of phase transitions of six binary Sn–Zn reference alloys and fourteen ternary Sn–Zn–Al alloys using DTA method were investigated in this paper. DTA experiments were performed at the heating/cooling ...

Tópico(s): Intermetallics and Advanced Alloy Properties

2012 - Springer Science+Business Media | Journal of Thermal Analysis and Calorimetry

Artigo Revisado por pares

Simona Zlá, Bedřich Smetana, Monika Žaludová, Jana Dobrovská, Vlastimil Vodárek, Kateřina Konečná, Vlastimil Matějka, Hana Francová,

Tópico(s): Intermetallics and Advanced Alloy Properties

2012 - Springer Science+Business Media | Journal of Thermal Analysis and Calorimetry

Artigo Revisado por pares

Kateřina Mamulová Kutláková, Jonáš Tokarský, Pavel Kovář, S. Vojtěšková, A. Kovářová, Bedřich Smetana, Jana Kukutschová, Pavla Čapková, Vlastimil Matějka,

Preparation of nanocomposite kaolinite/TiO2, using hydrolysis of titanyl sulfate in the presence of kaolin was addressed. A variable (kaolin)/(titanyl sulfate) ratio has been used in order to achieve the desired TiO2 content in prepared nanocomposites. Calcination of the composites at 600 °C led to the transformation of the kaolinite to metakaolinite and to origination of metakaolinite/TiO2 composites. The prepared samples were investigated using X-ray fluorescence spectroscopy, X-ray powder diffraction, ...

Tópico(s): Pigment Synthesis and Properties

2011 - Elsevier BV | Journal of Hazardous Materials

Artigo

James M. Keller,

... Robert Schumann Giuseppe Verdi Clara Schumann Cesar Franck Bedrich Smetana Anton Bruckner Carl Reinecke Johannes Brahms Alexander Borodin ...

Tópico(s): Music Technology and Sound Studies

2011 - Association of College and Research Libraries | Choice Reviews Online

Artigo Revisado por pares

Vlastimil Matějka, Yong Lu, Petra Matějková, Bedřich Smetana, Jana Kukutschová, Miroslav Vaculík, V. Tomášek, Simona Zlá, Yiqiang Fan,

After a friction process several changes in phase composition of friction composites are often registered. High temperature, accompanied by high pressure induced during braking can cause initiation of chemical reactions which do not run at room or elevated temperatures under the atmospheric pressure. Most of the studies in the field of tribochemistry at friction surfaces of automotive semi-metallic brake linings deal with phenolic resin degradation and corrosion of metallic components. The paper ...

Tópico(s): Surface Treatment and Coatings

2011 - Elsevier BV | Applied Surface Science

Artigo Revisado por pares

Bedřich Smetana, Simona Zlá, Jana Dobrovská, Petr Kozelský,

Abstract The paper reports a study of temperatures of phase transitions of nine samples of real grades of low-alloyed steels, including one sample of pure iron, using differential thermal analysis. Temperatures of phase transitions were measured in the low-temperature interval (20 – 1 000 °C). Investigated systems were analysed at selected rates of heating/cooling and then temperatures of phase transitions for zero heating/cooling rate were determined. The results obtained are compared with temperatures ...

Tópico(s): Metallurgical and Alloy Processes

2010 - De Gruyter | International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde)

Artigo Revisado por pares

Jonathan Newmark,

... allow for a unique perspective on music physiology. Bedřich Smetana's autobiographical string quartet ends with the musical ...

Tópico(s): Neurology and Historical Studies

2009 - SAGE Publishing | Journal of Child Neurology

Artigo

David Brodbeck,

The early Viennese performances of Bedřich Smetana's opera "The Bartered Bride" (1866), took place in 1892–93, during a time of great tension between the Austro-Hungarian ...

Tópico(s): Historical Influence and Diplomacy

2009 - Modern Humanities Research Association | Austrian Studies

Artigo Revisado por pares

Marta Valášková, Gražyna Simha Martynková, Bedřich Smetana, Soňa Študentová,

Porous cordierites were prepared from mixtures of talc, kaolinite and vermiculite with alumina or aluminum hydroxide by sintering in an argon atmosphere at 1300 °C for 1 h (porous cordierites of Group I) and 2 h (porous cordierites of Group II). Group I and Group II were different in pore size distribution, quantitative content of mineral phases and cordierite structure parameters. The crystalline phases identified in porous cordierites prepared without vermiculite were cordierite (69–88 vol.%), protoenstatite ( ...

Tópico(s): Layered Double Hydroxides Synthesis and Applications

2009 - Elsevier BV | Applied Clay Science

Artigo Acesso aberto Revisado por pares

P. A. Prokofev, Natalia Kol’chugina, Kateřina Skotnicová, Г. С. Бурханов, Miroslav Kursa, M. V. Zheleznyi, N. A. Dormidontov, Tomáš Čegan, A. S. Bakulina, Yu. S. Koshkid’ko, Bedřich Smetana,

The wide application of Nd-Fe-B permanent magnets, in addition to rare-earth metal resource constraints, creates the necessity of the development of efficient technologies for recycling sintered Nd-Fe-B permanent magnets. In the present study, a magnet-to-magnet recycling process is considered. As starting materials, magnets of different grades were used, which were processed by hydrogen decrepitation and blending the powder with NdHx. Composition inhomogeneity in the Nd2Fe14B-based magnetic phase ...

Tópico(s): Rare-earth and actinide compounds

2020 - Multidisciplinary Digital Publishing Institute | Materials

Artigo Acesso aberto Revisado por pares

Man Liu, Michael Bernhard, Monika Kawuloková, Josef Walek, Maximilian Kern, Simona Zlá, Peter Presoly, Bedřich Smetana, Markéta Tkadlečková, Guang Xu, Youn‐Bae Kang, Christian Bernhard,

Continuous cooling transformation (CCT) diagrams represent roadmaps for producing all heat-treatable steels. CCT curves provide valuable information on the solid-state phase transformation sequence, depending on the defined cooling strategies, the alloying concept of the steel and previous processing steps. The experimental characterization of CCT diagrams is usually done on a laboratory scale applying thermal analysis of dilatometry. In current research studies, however, also other in-situ methods ...

Tópico(s): Metallurgy and Material Forming

2023 - Elsevier BV | Journal of Materials Research and Technology

Artigo Acesso aberto Revisado por pares

Tomáš Čegan, Daniel PETLÁK, Kateřina Skotnicová, Jan Juřica, Bedřich Smetana, Simona Zlá,

The possibilities of metallurgical preparation of 40Nb-60Al and 15W-85Al intermetallic compounds (in at.%) by plasma arc melting (PAM) and vacuum induction melting (VIM) were studied. Both methods allow easy preparation of Nb–Al alloys; however, significant evaporation of Al was observed during the melting, which affected the resulting chemical composition. The preparation of W–Al alloys was more problematic because there was no complete re-melting of W during PAM and VIM. However, the combination ...

Tópico(s): Metallurgical and Alloy Processes

2020 - Multidisciplinary Digital Publishing Institute | Molecules

Artigo Revisado por pares

Přemysl Beran, Martin Petrenec, Milan Heczko, Bedřich Smetana, Monika Žaludová, Miroslav Šmíd, Tomáš Kruml, L. Keller,

In-situ heating/cooling neutron diffraction experiments were performed on a γ-TiAl based alloy doped with Mo and/or C. The structural analysis was complemented by differential scanning calorimetry and electron microscopy. Description of high temperature α phase with new model of partially disordered α2′-Ti3Al phase instead of a fully disordered α-Ti is proposed. The atomic redistribution in the γ phase is related to a wide α-transus signal on the DSC curves. Sections of temperature phase stability ...

Tópico(s): Inorganic Chemistry and Materials

2014 - Elsevier BV | Intermetallics

Artigo Revisado por pares

Monika Žaludová, Bedřich Smetana, Simona Zlá, Jana Dobrovská, Andy Watson, Jiřina Vontorová, Silvie Rosypalová, Jana Kukutschová, Michal Cagala,

Tópico(s): Advanced materials and composites

2012 - Springer Science+Business Media | Journal of Thermal Analysis and Calorimetry

Artigo Revisado por pares

Bedřich Smetana, Simona Zlá, Monika Žaludová, Jana Dobrovská, Petr Kozelský,

Tópico(s): High-Temperature Coating Behaviors

2012 - Croatian Metallurgical Society | Metalurgija

Artigo Acesso aberto Revisado por pares

Petr Kawulok, Ivo Schindler, Bedřich Smetana, Ján Moravec, Andrea Mertová, Ľubomíra DROZDOVÁ, Rostislav Kawulok, Petr Opěla, Stanislav Rusz,

The nil-strength temperature, zero strength temperature and solidus temperature are significant parameters with respect to the processes of melting, casting and welding steels. With the use of physical tests performed on the universal plastometer Gleeble 3800 and calculations in the IDS software, the nil-strength temperatures, zero strength temperatures and solidus temperatures of nine non-alloy carbon steels have been determined. Apart from that, solidus temperatures were also calculated by the ...

Tópico(s): Aluminum Alloy Microstructure Properties

2020 - Multidisciplinary Digital Publishing Institute | Metals

Artigo Revisado por pares

Marta Valášková, Marianna Hundáková, Bedřich Smetana, Ľubomíra DROZDOVÁ, V. Klemm, David Rafaja,

Ceria-based metal oxides are promising redox materials for photocatalytic decomposition of N2O emissions. The objective of this work was to evaluate the structural properties of cordierite ceramics with anchored CeO2 nanoparticles produced by sintering talc, kaolin and vermiculite with CeO2 nanoparticles precursor. In this contribution, we discuss the effect of the presence of CeO2 nanoparticles on the softening and crystallization temperatures of cordierite, and the influence of the sintering procedure ...

Tópico(s): Nuclear materials and radiation effects

2019 - Elsevier BV | Applied Clay Science