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1

Skłodowska-Curie – na ramionach olbrzymów, pod prąd stereotypom

Petelenz B.

Chemik

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2013

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Vol. 67, nr 8

675--682

PL

W niniejszym artykule przypomniano najważniejsze osoby i okoliczności, które (pośrednio lub bezpośrednio) pomogły Marii Skłodowskiej-Curie – do dzisiaj jedynej laureatce Nagród Nobla zarówno z Fizyki jak i z Chemii – przygotować się do roli badacza. Wskazano niektóre aspekty jej własnego sposobu myślenia, który tak mocno zaważył na losach nauki i kultury światowej.

EN

The paper points out some circumstances and some people that – directly or indirectly – influenced the scientific development of Marie Skłodowska-Curie, the only winner of the Nobel Prizes both for Physics and for Chemistry. It also focuses on some aspects of her intellectual approach which revolutionized the science in the late 19th and early 20th century.

2

Model angular distribution functions in CA3, CA4 and CA6 structural units of glassy systems

Bergmański G., Feliziani S., Rybicki J.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2007

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Vol. 11, No 3

185-195

EN

We have calculated model partial angular distribution functions (pADFs) in CA3, CA4 and CA6 structural units, i. e. an equilateral triangle with three vertical anions, A, and a central cation, C, a regular tetrahedron with four vertical anions, A, and a central cation, C and a square bipyramid with six vertical anions, A, and a central cation, C. The model pADFs were calculated employing a simple Monte Carlo procedure: the ions were being shifted at random within 3D spheres of radius r with uniform probability density and the AAA, ACA and CAA angles were calculated for each random configuration. Repeating the calculation 10(8) - 10(9) times produced smooth probability densities for the angles' values. Conventional reference data so obtained can be applied to estimate the overall degree of deformation of the considered structural units in numerically simulated materials.

3

The scientific and cultural role of atomistics

Sosnowski R.

Nukleonika

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2005

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Vol. 50,suppl.3

5-10

EN

The development of the idea that atoms are the building blocks of matter is presented. This hypothesis began in the Ancient Greece and, independently, in the Ancient India. Arguments are presented that the fact that the atomic theory started in these two regions and not e.g. in Egypt, China or by the Mayas can be linked to their writing. In both Greece and India the alphabet contained letters and not pictograms as used in the three other cultures. The role of Islamic scholars in preserving the knowledge of the ancient atomic theories is presented. In the Middle Ages a significant part of the Greek philosophic treatises have been firstly learned via the Arab translations. It is shown that the atomic concept has not been developed in the Middle Ages. This was because the church found it to be in a disagreement with the Holy Scripture. The start of the modern scientific atomic theory is presented and the role of the established quantitative laws of chemical reactions is discussed. Arguments are presented that the atoms discovered in the nineteenth century did not have the qualities of the atoms proposed by the Ancient Greek philosophers. Contrary to the atoms proposed by the Greeks the former can be decomposed into more fundamental parts. The discussion of the possibility that quarks, leptons and quanta of interactions fields meet the above qualities is presented.

4

A new program package for structural analysis of computer simulated solids

Bergmański G., Rybicki J., Mancini G.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2000

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Vol. 4, No 4

555-573

EN

The opportunity to gain detailed information on representative set of rings and chains of atoms is of great importance in the analysis of medium-range order in the computer simulated structures of solids. A new program package (ANELLI) for ring and chain analysis of computer simulated atomic structures is presented. The paper includes detailed description of input and output files. The package presentation is followed by exemplary results obtained using our programs.

5

Short- and medium-range order in bismuth-silicate glasses: a solecular dynamics study

Witkowska A., Rybicki J., Laskowski R., Mancini G., Feliziani S., Alda W.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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1999

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Vol. 3, No 2

239-254

EN

We report on the results of classical molecular dynamics (MD) simulations of str ucture of amorphous 15 Bi2O3 85 SiO2 [% mol] and 40 Bi2O3 60 SiO2 [% mol], and their totally reduced forms, 15 Bi2 85 SiO2 [% mol], and 40 Bi2 60 SiO2 [% mol], respectively. The simulations have been perfo rmed in the isobaric-isoenthalpic ensemble, using a two-body interaction potential. The set of the potential parameters was constructed as a suitable com bination of the parameters which were previously proposed for pure Bi2O3, and SiO2. Both unreduced, and reduced sy stems were initially prepared as well equilibrated hot melts, and then slowly co oled down to 300K. The structural information from the MD simulations was obtained from radial and angular distribution functions, static structural factors, Voronoi polyhedra sta tistics, and ring analysis. The simulation results can be summarised as follows. In unreduced glass with 15% [mol] Bi2O3 contents, the silicon structural units (mainly regular tetrahedra) form continuous network, whereas in 40% [mol] Bi2O3 glass these units are disconnected. In both unreduced systems Bi ions have mainly six-fold oxygen co-ordination, and no dominating structural unit can be individuated. However, the distorted bismu th units form a continuous network. In both totally reduced glasses (15% Bi2 85% SiO2, and 40% Bi2 60% SiO2 [% mol]), the silica network is built entirely from corner shari ng SiO4 tetrahedra. The structure of the silica subsystem is similar to that of pure *-SiO2. After the reduction, the Bi-Bi co-ordination significantly increases, whereas the first neighbour distance decreases. Moreover, partial static structural fact ors for Bi-Bi pairs indicate that the medium-range order in reduced glasses exhi bits greater periodicity than in unreduced glasses. Neutral Bi atoms form small clusters within the silica matrix.