Wyniki wyszukiwania - BazTech

1

Rynek wykonawczy nie ponosi winy za opóźnienia w modernizacji infrastruktury

Popiołek J., Biedrzycka A.

Nowoczesne Budownictwo Inżynieryjne

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2008

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Nr 6

12-14

PL

Wywiad z Jarosławem Popiołkiem, prezesem zarządu Mostostalu Warszawa SA nt. powództwa przeciwko ministrowi sportu Drzewickiemu, o postępach i kosztach w budownictwie.

2

Pochodzenie bursztynu w opiniach polskich przyrodników do połowy XIX wieku

Popiołek J.

Kwartalnik Historii Nauki i Techniki

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2005

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R. 50, nr 3/4

135--148

EN

In antiquity, views on the origin o f amber were divided, but the predominant opinion, expressed by Pliny in Naturalis Historia and by Tacitus in his Germania, was that amber originated from resin. The earliest mention of amber in Polish writing appeared in herbals in the 16th century. Their authors, Stefan Falimirz and Hieronim Spiczyński, also held the veiw that amber was tree resin. In the 16th and 17th centuries, many European scholars came to believe that amber was of non-organic origin and constituted a kind of bituminous substance that flowed out of the ground and solidified on its suface or at the bottom of the sea. As evidence for the idea, they cited the flammability of amber, as well as the false claim that it is malleable immediatley after being extracted from the earth or the sea, and hardens only some time afterwards. The view on the non-organic origin of amber was adopted by Polish authors: Jan Jonston, Wojciech Tylkowski, Gabriel Rzączyński, and Krzysztof Kluk. A key factor involved was the authority enjoyed by such European scholars as Georgius Agricola, Andreas Aurifaber, Girolamo Cardano, and Anselmius Boethius de Boodt. The first decades on the 19th century saw a return to the theory according to which amber originated from the resin of trees. This radical change in views on amber was due largely to analyses of its chemical composition, which showed its similarity to resins, as well as geological research pointing to the cooccurrence of vegetable residue together with amber. The vegetable origin of amber was supported by the chemists F.J. John and J.J. Berzelius. Among Polish investigators of amber, Michał Bonawentura Potulicki, who conducted experiments on the hardening of resins, was the first to support this view. The geologist Gotlieb Pusch came to the same conclusion in the course o f his research on sediments in which amber was found. The last researcher to consider amber to be a bituminous substance was Stanisław Staszic. There were no doubts as to organic origin of amber in the minds of the authors of two monographs devoted to amber (both entitled O bursztynie [ On amber]), Jan Fryer (1833) and Jozef Haczewski (1838). The only moot point was the species of the tree from which amber originated. In fact, that has remained an open question up to the present day.

3

On the Cattabriga problem for airy equation in domains with curvilinear boundaries

Popiołek J.

Demonstratio Mathematica

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1998

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Vol. 31, nr 3

643-655

EN

This paper is concerned with the Cattabriga problem for Airy equation (a linear version of the Korteweg - de Vries equation) in domains with curvilinear boundaries. Applying the potential method we shall reduce the problem considered to a system of Volterra integral equations and then prove the existence of a solution of this system.This paper is related to the previous investigations, where the said problem has been solved in rectangular domains.