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1

On the Question of Ferromagnetism in Proton and He-Irradiated Carbon

100%

Szczytko J., Juszyński P., Teliga L., Twardowski A., Stonert A., Ratajczak R., Korman A.

Acta Physica Polonica A

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2008

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vol. 114

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issue 5

1387-1390

EN

We tried to repeat the observation of the ferromagnetic response in proton and He-irradiated carbon made by the group of Esquinazi et al. We used He^+ and H^+ beams focused on graphite sample. The amount of charge deposited in the sample was comparable to the amount of charge used by Esquinazi. Magnetic measurements were performed in SQUID magnetometer. The magnetization of the samples before and after irradiation was compared. We did not observe any ferromagnetic enhancement of magnetization of our irradiated samples. Even if experiment was not the same as Esqinazi's one, we can exclude some of the mechanisms of ferromagnetism proposed by Esquinazi.

2

The Use of Analytical Methods in Evaluation of Coptic Wall Paintings Conservation - A Case Study

100%

Ali M., Abd El Aal S., Mahgoub G., Sihame A., Turos A., Korman A., Stonert A.

Acta Physica Polonica A

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2011

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vol. 120

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issue 1

171-176

EN

Egypt has a lot of ancient monasteries and churches, which were decorated with different kinds of wall paintings. Structure of these wall paintings consists of support, plaster and painting layers. Paintings deterioration is primarily due to physicochemical, natural and human factors. The most detrimental factors are bat patches, old varnish and organic waste of birds. All these lead to the gradual disappearance of paintings. Modern technology of conservation is focused on application of new materials for cleaning of wall paintings. Here we report on the use of enzymes, for cleaning surface of coptic wall paintings. Analytical techniques such as particle induced X-ray emission, Fourier transform infrared and optical microscopy were used to evaluate the enzymatic cleaning processes of coptic wall paintings and to identify the chemical composition of red, yellow and white pigments. Particle induced X-ray emission results indicated that there is no change in the chemical composition of the materials and pigments due to enzymatic cleaning. Fourier transform infrared and optical microscopy results confirmed the stability of organic medium before and after treatment of different kind of patches.

3

Materials Research on Archaeological Objects Using PIXE and Other Non-Invasive Techniques

100%

Miśta E., Stonert A., Korman A., Milczarek J., Fijał-Kirejczyk I., Kalbarczyk P., Wiśniewska A.

Acta Physica Polonica A

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2015

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vol. 128

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issue 5

815-817

EN

An interdisciplinary study of metallic objects from selected archaeological sites in Poland was performed. The aim of the project was to obtain information about the chemical composition and structural changes of the objects. Furthermore, the research results provided information about the technological process which was used to manufacture the artifacts. The materials research had a non- and micro-invasive character which is very important in this type of investigation. The main experimental tools were particle-induced X-ray emission supplemented with nuclear reaction thermal neutron (white beam) radiography, scanning electron microscopy with X-ray energy dispersive analysis, and laser ablation inductively coupled plasma mass spectrometry techniques. The results show that the artifacts were made by a secondary smelting process used in local metallurgy manufactures.

4

Heavy Ion Beams for Radiobiology: Dosimetry and Nanodosimetry at HIL

68%

Kaźmierczak U., Bantsar A., Banaś D., Braziewicz J., Czub J., Jaskóła M., Korman A., Kruszewski M., Lankoff A., Lisowska H., Pietrzak M., Pszona S., Stępkowski T., Szefliński Z., Wojewódzka M.

Acta Physica Polonica A

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2015

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vol. 127

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issue 5

1516-1519

EN

Ionizing radiation induces a variety of DNA lesions, including single and double strand breaks. Large energy deposition precisely localized along the ion track that occurs in the case of heavy ion irradiation can lead to complex types of DNA double strand breaks in exposed biological material. The formation of nuclear double strand breaks triggers phosphorylation of histone H2AX, which can be microscopically visualized as foci in the γ-H2AX assay. Studies with a carbon ion beam are being carried out at the Heavy Ion Laboratory of the University of Warsaw. The γ-H2AX assay as a method of measuring the biological response of cells irradiated with ^{12}C ions as well as the frequency cluster size distributions obtained in the nanodosimetry experiment at HIL will be presented.

Refine search results

On the Question of Ferromagnetism in Proton and He-Irradiated Carbon

The Use of Analytical Methods in Evaluation of Coptic Wall Paintings Conservation - A Case Study

Materials Research on Archaeological Objects Using PIXE and Other Non-Invasive Techniques

Heavy Ion Beams for Radiobiology: Dosimetry and Nanodosimetry at HIL