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Number of results: 15
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Abstract

Requirements for environmental protection, such as reducing emissions of CO2, NOx, and SO2 are the reason for growing interest in new technologies for coal utilization. One of the most promoted technologies is coal gasification. However, like any technology using coal, this process produces wastes – fly ash and slag. Due to the small number of coal gasification plants, these wastes are poorly understood. Therefore, before making decisions on the introduction of coal gasification technology, a waste utilization plan should be developed. This also applies to the slags formed in underground coal gasification technology. One of the options under consideration is to use these wastes as a component in mineral binders of a pozzolanic character. This paper compares the properties of two types of slags. The first slag (MI) comes from fuel gasification, and the second slag (BA) is from underground coal gasification. Slag MI can be classified as basic slag with a chemical composition similar to that of silica fly ash from coal combustion. Slag BA – because of its four times greater content of calcium oxide – belongs to a group of weakly basic slags. The main and only mineral component of slag MI is glassy phase. Slag BA forms – besides the glassy phase – crystalline phases such as mullite (3 Al2O3 · 2 SiO2), quartz (-SiO2), anorthite (Ca(Al2Si2O8)), gehlenit (Ca2Al[(Si,Al)2O7]), wollastonite (Ca3[Si3O9]), 2CaO · SiO2, and 4 CaO · Al2O3 · Fe2O3. The results of analyses have shown that slag BA has better pozzolanic properties (the pozzolanic activity index is 75.1% at 90 days) than slag MI (69.9% at 90 days) The preliminary studies lead to the conclusion that these slags are characterized by very low pozzolanic activity and cannot be used as a pozzolanic material.

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Authors and Affiliations

Maciej Mazurkiewicz
Ewelina Tkaczewska
Radosław Pomykała
Alicja Uliasz-Bocheńczyk
ORCID: ORCID
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Abstract

The processes occurring at the marine water - atmosphere boundary layer and involving selected important components of our environment arc discussed. Special attention is focused on the specific role of the marine water surface microlayer in transfer of those components, properties of aerosols, fundamental question of CO2 absorption/desorption balance and environmental conditions enabling re-emission of mercury from marine water into the atmosphere. Simple laboratory experiments on CO2 absorption from atmosphere and desorption of CO2 from marine water arc shown as an initial point for any wider discussion on the global carbon budget. The emission of mercury to the atmosphere is considered to be promoted by the solar radiation. Under strong solar radiation the ability of organic matter to reduce these ions is enhanced thus making the emission more effective. The phenomenon observed seems to be confirmed by the analysis of the data for months of low and high radiation intensity. A sign i fi cant role of atmospheric iron in cutophication of southern Baltic is emphasized. Concentration of this clement in dry and wet deposition is, however, too low to prevent limitation of phytoplankton growth in marine water.
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Authors and Affiliations

Lucyna Falkowska
Anita Lewandowska
Jozef Magoński
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Abstract

In the present paper, elemental Fe, Cr and Ni powders were used to fabricate nano-structured duplex and ferritic stainless steel powders by using high energy planetary ball milling. We have studied the effect of milling atmosphere like wet (toluene) and dry (argon) milling of elemental Fe-18Cr-13Ni (duplex) and Fe-17Cr-1Ni (ferritic) powders for 10 h in a dual drive planetary mill. Stearic acid of 1wt. % was added during milling to avoid agglomeration. The dry and wet milled duplex and ferritic stainless steel powders were characterized by XRD, SEM and particle size analysis techniques. We have found that both the milling atmospheres have great influence in controlling the final particle morphology, size and phase evolution during milling. It was reported that dry milling is more effective in reducing particle size than the wet milling. The Nelson-Riley method of extrapolation was used to calculate the precise lattice parameter and Williamson-Hall method was used to calculate the crystallite size and lattice strain of both the stainless steel milled in argon atmosphere. Dry milled duplex and ferritic stainless steel were then consolidated by conventional sintering method at 1100, 1200 and 1300°C temperatures under argon atmosphere for 1 hour.

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Authors and Affiliations

R. Shashanka
Orhan Uzun
D. Chaira
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Abstract

The article presents the results of research on the physicochemical and mechanical properties, microstructure, and the tendency to form shrinkage of nodular cast iron depending on the type of inoculant used for secondary inoculation. Six different inoculants containing different active elements in their chemical composition were used for the research. Step castings and Y2 wedges were made on the vertical forming line using an automatic pouring machine. The inoculation in the amount of 0.2% was made using a pneumatic dispenser equipped with a vision system controlling the effectiveness of the inoculation. The results of the thermal analysis were determined and compared, and the potential of each of the inoculants was assessed.
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Bibliography

[1] Fraś, E., Podrzucki, C. (1978). Modified cast iron. Kraków: Skrypt AGH, nr. 675. (in Polish).
[2] ITACAX™ – Final iron control. Retrieved November 10, 2021, from http://www.proservicetech.it/itacax-thermal-analysis-final-iron-quality-control/.
[3] Karsey S.I. (2000). Ductile iron I. Manufacturing. Warszawa: QIT, Fer et Titane Inc. (in Polish).
[4] Janerka, K., Kondracki, M., Jezierski, J., Szajnar, J. & Stawarz, M. (2014). Carburizer effect on cast iron solidification. Journal of Materials Engineering and Performance. 23, 2174-2181.
[5] Seidu, S.O. Thermal analysis of preconditioned ductile cast iron. International Journal of Current Engineering and Technology. 3(3), 813-818
[6] Lampic, M. (2013). Inoculation of cast irons: practice and developments. International Foundry, Research. 65(2).
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Authors and Affiliations

R. Dwulat
1 2
ORCID: ORCID
K. Janerka
2
ORCID: ORCID
K. Grzesiak
1

  1. Foundry Lisie Kąty, Lisie Kąty 7, 86-302 Grudziądz, Poland
  2. Department of Foundry Engineering, Silesian University of Technology, Towarowa 7, 44-100 Gliwice, Poland
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Abstract

In this investigation, the formation of oxide scales on different Co-Ni based superalloys of γ–γ′ type was analyzed. Co-20Ni-7Al-7W (at. %) alloy as well as its W-free modifications based on Co-Ni-Al-Mo-Nb and Co-Ni-Al-Ta systems was analyzed under conditions of high temperature oxidation at 800 and 900°C. Therefore, the alloys were isothermally oxidized at selected temperatures for 100 h in laboratory furnace. Afterwards, the oxidation products were evaluated by means of X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM). The performed tests showed that W-free alloys exhibit worse oxidation resistance compared to those of Co-Ni-Al-W alloys. After oxidation at 900°C, all alloys were prone of oxide spallation. The scales characterized by oxide peeling were mostly composed of complex Co-based oxides, including CoWO4, CoTa2O6, Co2Mo3O8, CoNb2O6.

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Authors and Affiliations

D. Migas
ORCID: ORCID
M. Kierat
ORCID: ORCID
G. Moskal
ORCID: ORCID
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Abstract

In this article, the Hui Muslim tradition of posting the names of donors during Ramaḍān and ʿĪd al-Fiṭr is illustrated with an example from the city of Liáochéng in 2019. In the past, these notices were posted on the perimeter walls of the mosques of Chinese Muslims on the eve of the festival of breaking the fast, which is a custom not otherwise found in the Islamic-influenced world, shows Chinese influence, and fulfilled a number of functions for the communities concerned. In the meantime, this tradition is no longer practised and, according to people who can confirm this, has been stopped by the authorities as part of some campaign against religious propaganda.
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Authors and Affiliations

Michael Knüppel
1
ORCID: ORCID

  1. Liaocheng University, China
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Abstract

The article intends to analyze the importance of the encounter with the most dramatic voice of the second half of the twentieth century in Italy, the poet Amelia Rosselli, in the works of Antonella Anedda, in order to show how the acquaintance with Rosselli, started in the early eighties, has turned for Anedda into an intense, creative and human dialogue, aimed at questioning the classic postures of the lyric persona as well as the cliché that connects female poetry with a confessional dimension. The purpose of the article is to show how Anedda, constantly consulting the Rossellian work (with a particular predilection for Diario ottuso, first published in a journal in 1980), recognizes a “sororal magisterium”, starting from which to build a lyric witness, anchored to the choral and ethical dimension of writing.
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Bibliography

1. ANEDDA, A. (1993): “Introduzione”, in: ROSSELLI, A., Impromptu, C. Mancosu Editore, Roma.
2. ANEDDA, A. (1997): Cosa sono gli anni. Saggi e racconti, Fazi, Roma.
3. ANEDDA, A. (1999): Notti di pace occidentale, Donzelli, Roma.
4. ANEDDA, A. (2000): La luce delle cose. Immagini e parole nella notte, Feltrinelli, Milano.
5. ANEDDA, A. (2004): “n dialogo con Caroline Lüderssen”, in: SANNA, S. A. (a cura di): A colloquio con: interviste con autori italiani contemporanei, Franco Cesati, Firenze.
6. ANEDDA, A. (2016): “Saggio ottuso”, in: Nuovi Argomenti, aprile‑giugno, 76, 22–28 [prima versione con lievi variazioni, in: CORTELLESSA, A. (2007) (a cura di): La furia dei venti contrari. Variazioni Amelia Rosselli, Le Lettere, Firenze].
7. ANEDDA, A. (2016): Amelia Rosselli, intervento per la Radiotelevisione Svizzera, registrato il giorno 11 ottobre 2016 e consultabile on line al sito https://www.rsi.ch/speciali/cultura/elogiodella- follia/?f=podcast-shows.
8. ANEDDA, A. (2019): “Introduzione”, in: SERMINI, S.: «E se paesani/ zoppicanti sono questi versi». Povertà e follia nell’opera di Amelia Rosselli, Olschki, Firenze, V–VII.
9. ANEDDA, A. (2021): Geografie, Garzanti, Milano.
10. BALDACCI, A. (2014): La necessità del tragico, Transeuropa, Bergamo.
11. BERARDINELLI, A. (1994): La poesia verso la prosa. Controversie sulla lirica moderna, Bollati Boringhieri, Torino.
12. BORGNA, E. (2014): La fragilità che è in noi, Einaudi, Torino.
13. CARPITA, C. (2017): “Per una poetica dell’inclinazione: scrittura del trauma ed etica relazionale nella poesia di Amelia Rosselli”, Carte Italiane, 2 (11), 21–42.
14. CAVALLERO, A. (2014): Inclinazioni. Critica della rettitudine, Raffaello Cortina Editore, Milano.
15. DONATI, R. (2020): Apri gli occhi e resisti. L’opera in versi e in prosa di Antonella Anedda, Carocci, Roma.
16. GALAVERNI, R. (2002): Dopo la poesia: saggi sui contemporanei, Fazi Editore, Roma.
17. PRINCIOTTA, C. (2014): “La scuola dei viventi. Il tragico in De Angelis e Anedda”, in: ALFONZETTI, B./ BALDASSARRI, G./ TOMASI, F. (a cura di): Cantieri dell’italianistica. Ricerca, didattica e organizzazione agli inizi del XXI secolo. Atti del XVII congresso dell’ADI – Associazione degli Italianisti (Roma Sapienza, 18–21 settembre 2013), Adi editore, Roma, 1–6.
18. ROSSELLI A. (2004): Una scrittura plurale. Saggi e interventi critici, Interlinea, Novara.
19. ROSSELLI, A. (2010): “È vostra la vita che ho perso. Conversazioni e interviste”, in: VENTURINI, M./ DE MARCH, S. (a cura di): Le Lettere, Firenze.
20. ROSSELLI, A. (2012): “L’opera poetica”, in: GIOVANNUZZI, S. (a cura di): Mondadori, Milano.
21.TANDELLO, E. (1997): Amelia Rosselli: la fanciulla e l’infinito, Donzelli, Roma.
22. VERBARO, C. (2010): “Natura morta con cornice. La poesia di Amelia Rosselli”, Italian Poetry Review. Plurilingual Journal of Creativity and Criticim, 5, 315–330.
23. ZANZOTTO, A. (2001): “Scritti sulla letteratura”, vol. 2, in: VILLALTA, G. M. (a cura di): Mondadori, Milano.
24. ZUBLENA, P. (2005): “Il domestico che atterrisce. La tentazione del quotidiano nella poesia di oggi”, in: ALFANO, G./ BALDACCI, A. et al. (a cura di): Parola plurale. Sessantaquattro poeti italiani fra due secoli, Sossella, Roma, 53–66.

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Authors and Affiliations

Alessandro Baldacci
1

  1. Uniwersytet Warszawski, Warszawa
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Abstract

B a c k g r o u n d: Regulation of energy balance in patients with short bowel syndrome (SBS) is disturbed due to lack of significant part of the intestine. The goal of the research was to analyse the plasma concentrations of selected regulatory peptides — ghrelin, visfatin, and irisin — in children with SBS.

M e t h o d s: To achieve this aim we recruited study group consisted of 28 children with SBS fed parenterally for at least two weeks, mean age 14 ± 5 months and mean standardised body mass index (SDS-BMI) –1.26 ± 0.84. The control group was represented 25 healthy children of matching age and SDS-BMI. The plasma concentrations of peptides (ghrelin, visfatin, and irisin) were determined using immunoassays, and liver enzymes (AST, ALT, GGT) using an auto-analyser.

R e s u l t s: We observed lower visfatin and ghrelin levels in the study group as compared to controls (both P <0.0001). The lowest total ghrelin concentration was observed in SBS children after ileal resection (P = 0.0016). Irisin concentration did not differ between the groups. Most of the SBS children showed elevated liver enzymes activities at the first measurement and during one-year follow-up.

C o n c l u s i o n: Our findings showed that plasma ghrelin and visfatin themselves may play a role in the course of SBS, while a lack of disturbance in irisin might imply that it is neither playing any role nor it is affected by SBS itself.

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Authors and Affiliations

Julita Pabisek-Miernik
Barbara Kościelniak-Merak
Mikołaj Spodaryk
Przemysław J. Tomasik
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Abstract

The “Kępa Redłowska” reserve is located in the southern part of Kępa Redłowska. The location of the reserve is quite unique. Its eastern border runs along the coastline of the Baltic Sea, while on the other sides it is surrounded by highly urbanized districts of Gdynia. Its coastal location means that it is exposed to natural factors that operate in the coastal zone, whereas its urban surroundings are a threat to the natural environment through more or less controlled human activity. The landscape of the reserve owes its attractiveness mainly to the cliff coast it encompasses. Diversified geological structure of this area, both in terms of lithology and age, combined with progressive erosion, causes a continuous change in its appearance. It is this part of the reserve that is most exposed to the destructive activity of natural factors, mainly coast erosion as well as aeolian processes. The intensity of these processes is closely related to climate changes over the centuries, e.g. a significant reduction in the number of winters, during which there is ice cover in the shore zone means that cliffs are not protected against erosion by winter storms. A spectacular effect of winter storms in this area was a large landslide in the southern part of the cliff on February 15, 2018. The retreat of cliffs is a common phenomenon, however observations in recent decades clearly indicate its acceleration. The remaining part of the reserve area, not directly connected with the shore zone, is subjected to continuously growing anthropopressure. As mentioned above, the “Kępa Redłowska” reserve is located in Gdynia. The expansion of the Redłowo district has resulted in the housing development being located directly adjacent to the eastern border of the reserve. An additional element of anthropopressure is the creation of interpretive trails and tourist routes within the reserve. On the one hand, this is an attempt to “channel” tourist traffic in this area, on the other hand, it causes an increase in tourist traffic with all the negative phenomena associated with it, mainly for vegetation. Human interference in the reserve began already at the end of the 1930s. At that time, military facilities, such as bunkers and artillery positions, were built there. This process continued uninterrupted until the 1960s. Post-military objects are on the one hand an attraction for tourists, on the other hand they attract the attention of various types of seekers of military remnants who, during their explorations, cause additional damage to the surface of the area and vegetation.

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Authors and Affiliations

Aneta Marek
Ireneusz J. Olszak
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Abstract

In the over 150 years of hydrocarbon history, the year 2017 will be one of the many similar. However, it will be a breakthrough year for liquefied natural gas. In Asia, China grew to become the leader of import growth, becoming the second world importer, overtaking even South Korea and chasing Japan. The Panama Canal for LNG trade and the “Northern Passage” was opened, so that Russian LNG supplies appeared in Europe. The year 2017 was marked by a dramatic shortening of the length of long-term concluded contracts, their shorter tenure and reduction of volumes – that is, it was another period of market commoditization of this energy resource. The article describes the current state of LNG production and trade till 2018. It focuses on natural gas production in the United States, Qatar, Australia, Russia as countries that can produce and supply LNG to the European Union. The issue of prices and the contracts terms in 2017 was analyzed in detail. The authors stress that the market is currently characterized by an oversupply and will last at least until mid–2020. Novatek, Total – Yamal-LNG project leaders have put the condensing facility at 5.5 million tons into operation. The Christophe de Margerie oil tanker was the first commercial unit to cross the route to Norway and then further to the UK without icebreakers and set a new record on the North Sea Road. In 2017, the Russian company increased its share in the European gas market from 33.1 to 34.7%. In 2017, Russia and Norway exported record volumes of „tubular” – classic natural gas to Europe (and Turkey), 194 and 122 billion m3 respectively, which is 15 and 9 billion m3 more natural gas than in 2016. The thesis was put forward that Russia would not easily give up its sphere of influence and would do everything and use various mechanisms, not only on the market, that it would simply be more expensive and economically unprofitable than natural gas. It was also emphasized that the pressure of the technically possible and economically viable redirection to European terminals of methane carriers landed in the American LNG, results in Gazprom not having a choice but to adjust its prices. The Americans, but also any other supplier (Australia?) can simply do the same and this awareness alone is enough for Russian gas to be present in Europe at a good price.

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Authors and Affiliations

Andrzej P. Sikora
Mateusz Sikora
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Abstract

In spite of technological, logistic and economic difficulties, interest in renewable energy sources in the world is consistently increasing. This trend is also observed in Poland, mainly due to the urgent need to tackle the problem of climate change, which is caused by the increasing concentration of gaseous pollutants in the atmosphere. The paper presents a short script of the issue of estimating renewable energy resources in Poland in the context of creating local low carbon economy plans at the level of municipalities/counties where RES sources should be taken into account. The author proposed an individual approach to estimate the potential of RES, taking the local conditions and the short characteristics of the small and medium companies sector in Poland into account. These companies have a great application potential to increase the share of renewable energies and to improve energy efficiency in their business. The actions, which are taken by the Ministry of Energy in the field of civil energy development, enhancing local energy security and the sustainable development of renewable energy resources support the development of energy clusters covering one district or five municipalities. In the article, the author presents data on the number of companies possessing a concession for generating electricity in RES installations in the power range from 40 kW to 200 kW. These companies can largely be the nucleus for creating a local cluster in which microgrids will be a key element.

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Authors and Affiliations

Tomasz Mirowski
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Abstract

A method for modeling of the dynamics characteristics for a 5-phase permanent magnet tubular linear motor (PMTLM) is presented. Its electromagnetic nonlinear field analysis with finite element method (FEM) has been coupled with the circuit model. The calculation model includes the equations for electrical circuits and mechanical quantities as well. They have been obtained using Lagrange's method. The calculated and measured waves of the mover position have been compared for several values of the excitation current. This comparison yields a good agreement. Presented calculation model is very useful in designing and optimization of the PMTLM and in the calculation of the parameters for the control algorithms intended for such a type of actuators.
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Authors and Affiliations

Bronisław Tomczuk
Andrzej Waindok
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Abstract

Lyme disease is an emerging problem in Poland. Analysis has been undertaken of the medical documentation of 86 patients hospitalized in the Infectious Diseases Department, University Hospital in Cracow in 2013–2016, suspected of Lyme arthritis. It has especially considered medical history including potential exposure to the infection, detailed characteristics of the symptoms, diagnostic challenges and results of the treatment. Only some patients had a history of erythema migrans and not all of them recalled tick-bite. The majority of the patients had affected large joints, especially knee joints, and polyarthritis was rarely observed. Symptoms were resolved completely or partially after antibiotic treatment in most patients. The diagnosis of Lyme arthritis in areas endemic for Lyme disease is still a diagnostic challenge in patients with other rheumatic diseases, including osteoarthritis.

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Authors and Affiliations

Katarzyna Stażyk
Jacek Czepiel
Martyna Gumulska
Aleksander Garlicki
Grażyna Biesiada
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Abstract

Ectopic pregnancy constitutes 2% of all pregnancies. In the last decades, due to the rising amount of caesarean sections, new localization of ectopic pregnancy has been observed — caesarean scar pregnancy (CSP). Cesarean scar pregnancy is an iatrogenic disease and a life-threatening condition which frequency will systematically rise. Because of possible serious complications, CSP should be swift ly diagnosed and treated. Th e purpose of this retrospective study was to demonstrate diff erent methods of CSP treatment performed between 2015–2018 in the Clinic of Endocrinological Gynaecology and Gynaecology Jagiellonian University Medical College in Cracow. Th e clinical characteristics, diagnosis, various methods of treatment and clinical outcomes were analysed. Defi nitive algorithm of CSP treatment is still not established. Pharmacological and operative methods are approved while expectant observation is considered unsafe due to possible risk of complications for the patient, including death.

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Authors and Affiliations

Katarzyna Doroszewska
Tomasz Milewicz
Tomasz Bereza
Anna Horbaczewska
Justyna Komenda
Estera Kłosowicz
Robert Jach
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Abstract

This article attempts to refute the generally accepted view that Jan Wojciech (Albert) Łubieński, Pantler of Sieradz, was the patron of Piotr Baryka,, the author of the comedy Z chłopa król ( The Peasant Become King), first staged in 1633 (editio princeps, 1637). The attribution results from a conjecture, which has never been properly verified, formulated by Ludwik Bernacki in 1904. Yet in the 1630s Jan Wojciech Łubieński held no public office (he was probably completing his education) and, crucially, did not become Pantler of Sieradz until 1643. In consequence, we presume that Baryka's patron may well have been Łubieński's uncle, a wealthy man renowned for his generosity, who had the same first name.
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Authors and Affiliations

Roman Krzywy
1
ORCID: ORCID

  1. Instytut Literatury Polskiej, Uniwersytet Warszawski

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