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33421. Ženy ve fyzice: pár slov o mezinárodní "fyzikální konferenci bez fyziky"

Creator:
Heyrovská, Raji, Kodymová, Jarmila, Krupková, Olga, and Musilová, Jana
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fyzika, konference, fyzičky, physics, conferences, women physicists, 6, and 53
Language:
Czech and English
Description:
Raji Heyrovská, Jarmila Kodymová, Olga Krupková, Jana Musilová. and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33423. Zeolite-bearing rocks from eluvial debris of Shchuchinskij synclinorium (Polar Ural, Russia): new petrographical and mineralogical data

Creator:
Smirnov, Pavel V., Konstantinov, Alexander O., Deryagina, Oksana I., Fatkullin, Eldar A., Shadrin, Andrey N., Batalin, Georgii A., Gareev, Bulat I. , and Trifonov, Artem A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Ca zeolites, Polar Urals, laumontite, and industrial potential
Language:
English
Description:
The territory of the Polar Urals is characterized by significant forecast resources of natural zeolites. In case of their successful development, the resources of the zeolite deposits can provide a positive impact on the development of a number of industries in the adjacent regions of the Urals and Western Siberia. At the same time, the available data about the zeolite-bearing rocks of the Polar Urals present in published research paper and materials of geological funds is rather contradictory. The results of research performed by different scientific groups often contain opposed conclusions on the mineralogical composition, the content of the commercial component in the ore, as well as on the ore reserves calculation and the potential of commercial exploitation for the same mineral occurrences. In many respects, this situation can be explained by the complexity of the geological and geomorphological conditions of the territory under consideration, the remoteness of the promising mineral occurrences from large scientific and industrial centers, and the variety of ore occurrences. This work presents the study results of lithological–petrographic features and the material composition of the eluvial debris of the Middle–Late (Givetian–Frasnian) Devonian zeolite-bearing rocks of the volcanogenic-sedimentary origin within the Naunpe area of the Polar Urals., The main objective of the proposed research was to evaluate the economic feasibility of their development and possible directions for commercial exploitation of this type of ores. Research methods included petrographic study of samples of zeolite-bearing rocks in thin sections, SEM-EDS, determination of the total mineral composition by XRD and the chemical composition by XRF. Within the Naunpe area, the outcrops of zeolite-bearing rocks on the surface are represented by blankets and debris of small lumpy–gravel eluvial deposits with indistinct outlines. Macroscopically, zeolite-bearing eluvial deposits are represented by reddish or pinkish in color, massive and relatively homogenous rocks. The ore occurrences are well interpreted based on the remote sensing data. According to the results of petrographic, lithological, and mineralogical studies, three main rock types were distinguished among the eluvial debris deposits: zeolite-bearing crystallo–lithoclastic tuffs of the mafic, intermediate, and felsic composition, and also tuffoargillites, and siliceous rocks., and Crystallo–lithoclastic tuffs and tuffoargillites contain Ca-zeolites, represented mainly by laumontite (13.8–18.9 %), which fill small open spaces between crystallites and lithoclasts. Volcanic glass fragments and feldspars from tuffoargillites are replaced partially or completely by zeolites. The content of zeolites in these rocks is even lower (less than 10 %). The characteristic features of the studied zeolite-bearing rocks from the ores of the known deposits of the Polar and Subpolar Urals have higher contents of Fe2O3, CaO и Na2O and lower content of K2O. The obtained results show that the studied rocks are quite complex, diverse, and polygenetic, as well as their formation is a result of several stages of post-volcanic authigenic mineral formation. The rather low content of zeolite minerals in these rocks and high variability of the material composition decrease the industrial potential of that eluvial debris deposits as an object of mineral raw material base. At this, they can be considered as prospecting indicator for prospecting the areas with a similar geological structure.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33424. Zero-reconstructible triangular norms as universal approximators

Creator:
Petřík, Milan and Sarkoci, Peter
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Zero-recnostructible strict triangular norm, approximation, multiplicative generator, and reconstruction
Language:
English
Description:
This paper is inspired by recent results [15, 16] which have shown that a multiplicative generator of a strict triangular norm can be reconstructed from the first partial derivatives of the triangular norm on the segment {0} x [0,1]. The strict triangular norms to which this method is applicable have been called zero-reconstructible triangular norms. This paper shows that every continuous triangular norm can be approximated (with an arbitrary precision) by a zero-reconstructible one, and thus substantiates the significance of this subclass of strict triangular norms.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33425. Zero-term ranks of real matrices and their preservers

Creator:
Beasley, LeRoy B. , Jun, Young-Bae , and Song, Seok-Zun
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
linear operator, zero-term rank, and $P,Q,B$-operator
Language:
English
Description:
Zero-term rank of a matrix is the minimum number of lines (rows or columns) needed to cover all the zero entries of the given matrix. We characterize the linear operators that preserve zero-term rank of the $m \times n$ real matrices. We also obtain combinatorial equivalent condition for the zero-term rank of a real matrix.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

33426. Zesilování rozmítnutých pulzů - cesta k nejvýkonnějším laserům světa

Creator:
Koubíková, Lucia
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
lasery, lasers, 6, and 53
Language:
Czech and English
Description:
Metoda zesilování rozmítnutých pulzů vyvinutá Donnou Stricklandovou a Gérardem Mourouem v roce 1985 a oceněná letošní Nobelovou cenou za fyziku způsobila doslova revoluci v konstrukci laserových systémů s vysokým špičkovým výkonem. Maximální intenzita dnešních laserů je až milionkrát vyšší než před 30 lety a jejich využití je celosvětové. Petawattové laserové systémy se uplatňují v celé řadě experimentů z oblasti biologie, fyziky materiálů, urychlování částic či laboratorní astrofyziky. Českou republiku v této oblasti úspěšně reprezentují laboratoře ELI Beamlines v Dolních Břežanech u Prahy, kde jsou v současnosti v provozu dva unikátní laserové systémy terrawatové a petawattové třídy L1 Allegra a L3 HAPLS., The Chirped Pulse Amplification method, developed by Donna Strickland and Gérard Mourou in 1985, which was awarded this year's Nobel Prize in Physics, has revolutionized the field of high peak power laser systems. The maximum intensity of today's lasers is almost a million times higher than it was 30 years ago and their application is worldwide. Experiments using petawatt laser systems range from biology, material physics, and particle acceleration to laboratory astrophysics. The Czech Republic is successfully represented in this field by the ELI Beamlines facility located in Dolní Břežany near Prague, which houses two unique terawatt and petawatt class laser systems L1 Allegra and L3 HAPLS., Lucia Koubíková., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33427. Zévy - mlži, kteří fotosyntetizují

Creator:
Černohorská, Nicole
Format:
print, bez média, and svazek
Type:
article, text, články, journal articles, model:article, and TEXT
Subject:
Biologické vědy, mořští měkkýši, mlži, korálové útesy, fotosyntéza, ohrožené druhy, sea molluscs, Bivalvia, coral reefs, photosynthesis, endangered species, Zévy, zooxantely, iridocyty, Tridacnidae, Giant clams, sea clams, 2, and 57/59
Language:
Czech
Description:
Zévy (Tridacnidae) jsou mezi mořskými mlži výjimečné velikostí i způsobem získávání potravy. V jejich plášti se vyskytují mikroskopické řasy zooxantely, které fotosyntézou produkují sacharidy, o něž se dělí s hostitelem. Za nápadné zbarvení pláště vděčí zévy zooxantelám a specializovaným buňkám iridocytům., Giant clams (Tridacnidae) are exceptional among sea clams for their size and the way they acquire food. On their shells microscopic zooxanthella algae occur, producing saccharides through photosynthesis, which they share with the host. The conspicuous coloring of the shells is due to the clams’ zooxanthellae and specialized iridocyte cells., and Nicole Černohorská.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

33429. Zhodnocení valenční teorie volebního chování na základě otevřených otázek ohledně důvodů volební neúčasti

Creator:
Lukáš Linek
Format:
print, bez média, and svazek
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Společenské vědy, výzkum veřejného mínění, public opinion polls, turnout, abstention, open-ended questions, valence politics, 18, and 3
Language:
Czech
Description:
Cílem studie je prozkoumat, zda lze tvrzení valenční teorie volebního chování ohledně motivací a důvodů volební účasti potvrdit na základě odpovědí na otevřenou otázku ohledně hlavního důvodu volební neúčasti. Konkrétně byla studována tvrzení, která se týkají konstrukce očekávaného užitku z volební účasti. K prozkoumání výše uvedených tvrzení valenční teorie ohledně motivací volební neúčasti byly využity otevřené otázky z pěti povolebních dotazníkových šetřeních konaných v Česku mezi lety 2004 a 2010. Výsledky ukazují, že nevoliči uvažují v dimenzích, které valenční teorie předpokládá. Ta totiž pro volební účast vyžaduje, aby jedinec očekával užitek z hlasování pro konkrétní stranu; tento užitek může být důsledkem jak pozičních, tak valenčních úvah. Analýza odpovědí na otevřené otázky ukázala, že hlavním důvodem neúčasti je to, že jedinci nenacházejí užitek z hlasování ve volbách a to za řady důvodů: malý význam politiky v jejich životě, jsou přesvědčení, že hlasováním nic neovlivní, nevědí pro koho hlasovat a nedůvěřují politikům., The aim of the study is to explore the valence theory’s account of voter turnout using open-ended questions which measured the main reason given by voters for electoral abstention. The focus was on the claim of the valence theory concerning the respondent’s expected benefit from participating in an election. Data from five post-election studies undertaken between 2004 and 2010 are analysed. The empirical results reveal that electoral abstention is explained by four key factors. Voters and non-voters differ as valence theory suggests because the latter exhibit less interest in politics, less trust in politicians and parties, less knowledge of who to vote for, and a feeling that voting does not change anything. These empirical results are consonant with the predictions made by valence theory and demonstrate that electoral participation is strongly determined by expected benefits., and Lukáš Linek.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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