Wyniki wyszukiwania - Biblioteka Nauki

1

Kolumna Zygmunta : jej kolejne przekształcenia i restauracje

100%

Lesiak K.

Ochrona Zabytków

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1997

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nr 2

121-141

EN

The column o f Zygmunt III Vasa, erected in Warsaw in 1644, is the oldest and most magnificent secular historical monument in the capital. In the course o f over 3 5 0 years it was subjected to numerous conservation, restoration, and reconstruction undertakings. The author recalls and places in order consecutive conservation work upon the basis of unpublished and heretofore scattered documents, presenting the changes to which the monument was subjected in particular eras. The contemporary form o f the column is a conglomerate of numerous elements which came into being in assorted periods o f time. From the architectonic point o f view it remains rather faithful to the original, less so as regards the sculpture, while its colour differs completely. The enclosed colour plate illustrates the gradual reduction o f colour from contrasting blacks, reds, browns and gold, characteristic for the Vasa era, to contrasts between three shades o f grey and brown. O wing to the fact that the most recent conservation was limited to protection and reinforcement, the author postulates an extensive conservation programme aiming at restoring the Baroque nature o f the object.

2

Marian Lesiak (1919-1999)

75%

Lesiak K.

Ochrona Zabytków

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2000

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nr 2

211-213

3

Concept of using the heat pipes in the heat exchanger of diesel engine exhaust system intended for use in potentially explosive atmospheres

51%

Lesiak K. , Brzeżański M. , Prostański D.

Combustion Engines

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2019

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tom R. 58, nr 2

127--131

EN

Limiting the temperature of exhaust gases to below 150°C is one of the necessary conditions for diesel engine to be used in a potentially explosive atmosphere. For this purpose heat exchangers are necessary to be used. This article presents the concept of exchanger in which heat pipes are used to transport thermal energy from the exhaust gases to the cooling medium.

4

Effectiveness of half masks for respiratory health protection in coal mining

51%

Drwięga A. , Williamson B. , Foster P. , Lesiak K.

Mining Machines

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2021

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tom no. 3

2--17

EN

An improved procedure is presented for testing the level of respiratory health protection and comfort of half masks currently used in coal mining and similar industries. This will allow companies to make the best choice of such equipment for their workers. Half masks used by one Slovenian (PV) and two Polish (JSW and PPG) coal mining companies were tested in terms of filtering efficiency, especially for PM2.5, perceived effectiveness, comfort and ease of use. Filtering efficiency was determined by analysing filters from masks used in underground operations for the levels and sizes of trapped coal dust particles and by carrying out experiments employing a specially developed laboratory test stand. The latter incorporated a replica human head and a climatic chamber to simulate the humidity of exhaled air during mining activities. To determine the comfort and utility of the half masks, selected miners were asked to fill in questionnaires. The main results of these studies were that, in the interest of miners' health, and for those working in other high dust environments, the quality of the half-mask should be assessed on the basis of workplace and stand tests. These are complementary and both should be included to ensure the correct assessment of the half masks. For the masks supplied by the mentioned mining companies, their filtering efficiency for PM2.5, as determined using the test stand, was excellent at over 99%.

5

System of current collectors inertization for safety use in explosive atmosphere-testing and results

51%

Drwięga A. , Lesiak K. , Clausen E. , Getz M.

Mining Machines

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2023

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tom vol. 41, iss. 4

274--284

EN

R&D work regarding the innovative mine transportation system, planned to be powered by the three-phase busbar, developed within theRFCS project "Increase of mines efficiency and health protection through the innovative transport system based on BUSDUCT" is discussed. Assumptions regarding the construction of the locomotive and the production of nitrogen from the air for inerting purposes are discussed in the first part, whereas in the second part adapting thecurrent collector’s brushes to nitrogen injection, the relevant CFD calculations, the stand for testing the inertization, are presented. Many interesting experiments on the effectiveness of inertization using explosive mixtures of hydrogen and air are illustrated, described and discussed.