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Number of results: 29
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Abstract

The study reported in this paper was aimed at establishing the effect of values of parameters characterizing the process of superficial remelting of a nodular iron casting on the quantity of introduced heat, geometry of remeltings as well as parameter λ and hardness of cementite eutectic. The remelting process was carried out using GTAW method, at electric arc length of 3 mm in argon atmosphere, welding current intensities I = 50, 130, 210, and 300 A, and electric arc scanning speeds vs = 200, 400, and 800 mm/min. The measurements included estimation of the quantity of heat introduced to the casting in the electric arc-induced remelting process with the use of flow calorimeter. Widths and depths of remetlings were assessed with the use of metallographic method. As a result of fast solidification, cementite eutectic was obtained in remelted material in which, in the course of cooling down to ambient temperature, austenite was subject to partial transformation into martensite. To characterize the cementite eutectic, value of the structural parameter λ was assessed. Values of the parameter were similar for areas of occurrence of both fibrous and laminated eutectic. Remeltings were examined at half of their depths. Micro-hardness measurements were taken in the same areas. The established quantitative relationships may prove to be useful in practice for the purpose of predicting values of parameter λ and hardness of remeltings in studies aimed at improving resistance of cast-iron castings to abrasive wear.
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Authors and Affiliations

M. Korzeniowski
A. Trytek
B. Kupiec
A.W. Orłowicz
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Abstract

The paper discusses the possibility of improving resistance of heat exchangers made of gray cast iron with flake graphite to hightemperature corrosion by providing them with metallic coatings. A metallic coating containing 76.9% Ni, 19.8% Cr, 1.7% Si, 0.9% Fe, and 0.9% Mn was applied by means of the plasma spraying method and subjected to cyclically variable thermal loads in the atmosphere of solid fuels combustion products (oxygen, sulfur, chlorine, and sodium). In a 30-day thermal load test held at temperature 500°C it has been found that thickness of the metallic coating decreased from the initial (240 ± 6) μm to (231 ± 6) μm. The depth to which sulfur, chlorine, and sodium penetrated the coating was about 30 μm. Increased oxygen content occurred along the whole coating depth. In the coating area adjacent to the substrate surface, the content was twice as high compared to this observed in the initial coating material. Although presence of oxygen was found within the whole depth of the coating, i.e. (231 ± 6) μm, no signs of susceptibility of the sprayed metallic layer to separation from substrate of gray cast iron with flake graphite were found.
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Authors and Affiliations

A. Trytek
M. Tupaj
M. Mróz
A.W. Orłowicz
M. Radoń
M. Jacek
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Abstract

Based on the example of the development process of the cast suspension of a special-purpose vehicle the application of the integrated engineering design methodology (ICME – Integrated Computational Materials Engineering) and the development of construction has been presented. Identification of the operating and critical loads, which are guidelines for carrying out the structure strength shaping process, material and technological conversion, are due to the needs and requirements of the suspension system and the purpose and objectives of the special mobile platform. The developed cast suspension element construction includes the use of high-strength AlZnMgCu aluminum alloy. The properties of the used alloy and designed shape allows for the transfer of assumed operating loads in normal exploitation conditions and in the dynamic, critical loads to the susceptibility to damage in the assumed casting areas. For the proposed design, conducted numerical analyzes includes the impact of the shock wave pulse on the occurrence of the destructive stress fields. Based on their distribution, the areas of possible decomposition of the structure of the design element were estimated. The results allowed to devise an element with predicted destructions that allow to absorb a significant part of the impact energy of the shock wave front, which is also the buffer zone for the propagation of destruction for the critical kinematic nodes of the system.
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Authors and Affiliations

M. Maj
R. Żuczek
J. Piekło
S. Pysz
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Abstract

A research of wear resistance of an austenitic cast iron with higher resistance to abrasive-wear and maintained corrosion resistance characteristic for Ni-Resist cast iron is presented. For the examination, structure of raw castings was first formed by proper selection of chemical composition (to make machining possible). Next, a heat treatment was applied (annealing at 550 °C for 4 hours followed by air cooling) in order to increase abrasive-wear resistance. One of the factors deciding intensity of wear appeared to be the chilling degree of castings. However, with respect to unfavourable influence of chilling on machining properties, an important factor increasing abrasivewear resistance is transformation of austenite to acicular ferrite as a result of annealing non-chilled castings. Heat treatment of non-chilled austenitic cast iron (EquNi > 16%) resulted in much higher abrasive-wear resistance in comparison to the alloy having pearlitic matrix at ambient temperature (EquNi 5.4÷6.8%).
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Authors and Affiliations

D. Medyński
A. Janus
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Abstract

The paper describes influence of rare earth metals (REMs) on G20Mn5 cast steel microstructure and mechanical properties. The cerium mixture of the following composition was used to modify cast steel: 49.8% Ce, 21.8% La, 17.1% Nd, 5,5% Pr and 5.35% of REMs. Cast steel was melted in industrial conditions. Two melts of non-modified and modified cast steel were made. Test ingots were subject to heat treatment by hardening (920°C/water) and tempering (720°C/air). Heat treatment processes were also performed in industrial conditions. After cutting flashes off samples of cast steel were collected with purpose to analyze chemical composition, a tensile test and impact toughness tests were conducted and microstructure was subject to observations. Modification with use of mischmetal did not cause significant changes in cast steel tensile strength and yield strength, while higher values were detected for fractures in the Charpy impact test, as they were twice as high as values for the data included in the PN-EN 10213:2008 standard. Observations performed by means of light and scanning microscopy proved occurrence of significant differences in grain dimensions and morphology of non-metallic inclusions. Adding REMs resulted in grain fragmentation and transformed inclusion shapes to rounded ones. Chemical composition analyses indicated that round inclusions in modified cast steel were generally oxysulphides containing cerium and lanthanum. In the paper the author proved positive influence of modification on G20Mn5 cast steel mechanical properties.
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Authors and Affiliations

J. Kasińska
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Abstract

Samoregulacja mediów może mieć istotny wpływ na kształtowanie się kultury dziennikarskiej i poziomu etycznego mediów. Jej skuteczność jest jednak uzależniona od stopnia instytucjonalizacji narzędzi samoregulacyjnych i ich powszechnej akceptacji. Różny jest ten poziom w różnych systemach medialnych, co często warunkowane jest historycznie. Artykuł za cel przyjmuje prezentację historycznego rozwoju samoregulacji trzech systemów medialnych (francuskiego, brytyjskiego i fińskiego) wpisujących się w trzy różne modele systemów medialnych opisane przez Daniela Hallina i Paolo Manciniego i zestawienie ich z rozwojem samoregulacji mediów w Polsce.
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Authors and Affiliations

Paweł Urbaniak
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Abstract

Artykuł charakteryzuje pismo „Moriah” wydawane we Lwowie w latach 1903–1924 jako miesięcznik młodzieży żydowskiej. Pismo ukazywało się w języku polskim i było trybuną środowiska syjonistycznego. „Moriah” zamieszczała teksty popularnonaukowe, głównie z zakresu historii i literatury żydowskiej oraz utwory literackie przedstawicieli literatury jidysz i hebrajskiej. Pismo realizowało model wychowania w duchu narodowo-żydowskim, ale przede wszystkim popularyzowało idee syjonizmu.
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Authors and Affiliations

Sabina Kwiecień
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Abstract

Przedmiotem rozważań jest analiza artykułów w czasopismach ukazujących się na przełomie XIX i XX w., które przedstawiały postać Jakuba Jasińskiego. Badaniami objęto następujące tytuły prasowe: „Czarno na Białem” (1939), „Echo Pragi” (1917), „Gazeta Warszawska” (1924), „Gazeta Wileńska” (1906), „Kurier Literacko-Naukowy” (1927), „Kurjer Polski” (1917), „Kurier Poranny” (1886), „Kurier Warszawski” (1917), „Nowa Reforma” (1918), „Nowa Gazeta” (1917), „Sybilla Nadwiślańska” (1821), „Świat” (1917), „Tygodnik Ilustrowany” (1917). Zamierzeniem autorów było ukazanie osoby Jasińskiego na tle historii Polski. Nawiązywano do Mickiewicza, jako tego, który starał się wynieść Jasińskiego do grona polskich patriotów. Obraz ten był wielokrotnie powielany.
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Authors and Affiliations

Aleksandra Tomicka
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Abstract

W artykule dokonano analizy pisma „Papier i Galanteria” ukazującego się w latach 1921–1922. Przedstawiono ogólny zarys działalności pisma. Omówiono: zasady funkcjonowania pisma, zadania i pełnioną rolę, adresatów, źródła finansowania, strukturę pisma, zawartość tekstów.
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Authors and Affiliations

Monika Olczak-Kardas
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Abstract

Czasopisma studenckie lat siedemdziesiątych i osiemdziesiątych były alternatywą dla systemu oficjalnej prasy literackiej i młodych PRL. Chociaż wydawane oficjalnie przez organizacje studenckie (ZSP, później SZSP), to ze względu na takie cechy komunikatu prasowego jak nieregularność ukazywania się, określenie gatunkowe - jednodniówka, niewielki nakład i nieoficjalny kolportaż ich redakcje posiadały względny atrybut samodzielności. Oczywiście w kontekście ówczesnego systemu kultury studenckiej, częściowo zideologizowanego. Do najważniejszych nieprofesjonalnych czasopism środowiskowych należały jednodniówki: „Dwukropek”, „Faktor”, „Gaudeamus”, „Konfrontacje”, „Linia”, „Magazyn Studencki”, „Spojrzenia”, „Smar”.
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Authors and Affiliations

Andrzej Buck
ORCID: ORCID
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Abstract

W niniejszym tekście przedstawiono współczesny obieg wydawnictw periodycznych w ramach wtórnego rynku książki. W swojej masie stanowią one w stosunku do książek marginalny dział asortymentu, aczkolwiek jest on stale obecny w ofercie wszystkich segmentów rynku, obejmujących zarówno obiekty zabytkowe, jak i nowsze, w tym bieżącą produkcję. Obecność ta jest jednak zróżnicowana pod względem jakościowym i ilościowym, na podaż i popyt zaś w istotny sposób wpływają zmiany technologiczne w zakresie rozpowszechniania prasy (Internet) oraz udostępniania jej zbiorów archiwalnych i bibliotecznych (digitalizacja).
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Authors and Affiliations

Grzegorz Nieć
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Abstract

W artykule prześledzono obecność psychoanalizy w wydawanych w latach 1946–1981 w Londynie „Wiadomościach”. Przeanalizowano teksty zarówno zwolenników teorii Freuda i jego kontynuatorów, jak i ich oponentów, próbując tym samym odpowiedzieć na pytanie: czy na łamach emigracyjnego tygodnika doszło do przedyskutowania użyteczności psychoanalizy jako języka opisu zjawisk społeczno-kulturowych?
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Authors and Affiliations

Jakub Osiński
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Abstract

This article offers a new reading of the complex, multidimensional, palimpsest identity of the eponymous hero of The King Spirit. Intended to be a total work of art (Gesamtkunstwerk), Juliusz Słowacki’s epic poem remains unfi nished, in a number of versions that are driven by two impulses, a centrifugal force reducing the poem to a string of inchoate fragments and a centripetal counterforce working for the poem’s unity. The same vectors seem to exert a permanent tension on the central character of the poem, a complex web of relations between body and soul, individual and universal consciousness, boundless and limited knowledge, the bright light of revelation and the inadequacy of words, and, last not least, between inspiration, memory and imagination. The peculiar construction of the ‘I’ in The King Spirit may also be seen as an attempt to relinquish the aesthetic mode of existence for the religious one (as described by Søren Kierkegaard). The poem could then be read as a dramatic record of that transition.
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Authors and Affiliations

Magdalena Siwiec
ORCID: ORCID
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Abstract

This article examines some aspects of a broader theme indicated in the title with respect to the diptych Tyrtaeus: A Tragedy and Behind the Scenes: A Fantastic Tale. While the present analysis is based on the fi ndings of earlier critics, it develops various parallels suggested by the use of musical motifs in Norwid’s twin dramas. Those associations act as an aid to a better understanding of the differences between the attitudes and ideas presented in the plays. Moreover, by indirectly marking the contrasts of truth and falsehood, they hold the key to the moral interpretation of the plays. The overall pattern of the musical references and associations in Tyrtaeus and Behind the Scenes appears to refl ect Norwid’s organic philosophy and his idea of creative originality. Finally, the purported pushing of Tyrtaeus off a cliff, an episode symbolizing the rejection of the right path, is analyzed along two similar poetic images of Norwid’s, Aesop’s fall into an abyss (On Freedom of Speech) and the hurling of Chopin’s piano out of the window (‘Chopin’s Piano’).
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Authors and Affiliations

Bartłomiej Łuczak
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Abstract

This is the first study of Comrade October, the only drama in the oeuvre of Kazimierz Wierzyński (1894–1969). Written in 1950, it was not published until 1992. The article traces the origins of the play and assigns it to the tradition of dystopian fi ction (as exemplifi ed primarily by George Orwell’s Nineteen Eighty-Four. A close reading of the structure of the play (the characters, the plot and its temporal structure, etc.) reveals the originality of Wierzyński’s approach and the links between Comrade October and the poetry he wrote after the war in exile.
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Authors and Affiliations

Jakub Osiński
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Abstract

Without question Tadeusz Nowak reached the height of his poetic powers in a series of poems he called psalms (Psalms for Home Use, 1959; Psalms, 1971; and New Psalms, 1978). Although they form a distinctive group with common characteristics, it is hard to see what could possibly connect them with the lofty verses of the Book of Psalms. Having said that it can be argued that they belong to a Polish tradition of psalms developed by Kochanowski, Kochowski and Krasiński. The Polish psalms come in two varieties, those with sweeping visions of national history and identity, and the homely, or more personal, in focus and tone. Nowak rarely mentions the grand themes, yet when he does so his utterances are pregnant with meaning (though with no touch of the messianic fervour typical of the Polish psalms). His Psalms for Home Use are decidedly ‘homely’ in the sense of being personal and private (even autobiographical), and because they exhibit a mind of the common people from the country. If there is any connection between Nowak’s Psalms and their Biblical prototype it is maintained not so much by the occasional literary allusion as by the casting of the characters in the poems in the role of modern psalmists. Like King David, they know they are sinners, and that knowledge imparts to their ‘psalms’ the candidness of a cry from the depth.
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Authors and Affiliations

Maciej Szargot
ORCID: ORCID

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