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1

Effect of Temperature on the Ion Beam Induced Luminescence of Oxide Powders Doped with Rare Earth Elements

100%

Gawlik G., Panczer G., Moncoffre N., Jagielski J.

Acta Physica Polonica A

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2013

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vol. 123

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issue 5

920-922

EN

The hydrogen ion beam induced luminescence of gadolinium oxide Gd_2O_3 doped with 1% of holmium (Ho) and 1% of bismuth (Bi) was investigated. Degradation of the holmium related 549 nm ion beam induced luminescence line intensity during hydrogen ion irradiation was observed. Two different mechanisms of the ion beam induced luminescence degradation has been proposed: the first one related to the accumulation of ion induced target material damage and the second mechanism related to the target temperature growth during ion beam bombardment. The experimental method for separation of both mechanisms effects was proposed and demonstrated.

2

Structural and Functional Properties of Ion Beam Modified Elastomers

88%

Jagielski J., Ostaszewska U., Bielinski D., Piatkowska A., Romaniec M.

Acta Physica Polonica A

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2013

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vol. 123

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issue 5

888-891

EN

Studies on the use of energetic ion beams for material modification have been initiated originally within the Manhattan project and have been continuously developed since then. The consecutive steps were devoted to the studies of ion implantation into semiconductors, metals, ceramics and, most recently, organic materials. One of the latest areas of applications is modification of elastomers, commonly known as rubbers. In the present paper the results of the studies on structural and functional properties of irradiated elastomers will be presented with the special emphasis on the materials used in aviation and military applications. Among the structural modifications, a massive loss of hydrogen atoms appears as the most peculiar characteristic of irradiated elastomers. Functional properties of irradiated rubbers: microhardness and friction coefficient, will be presented and application potential of the materials discussed.

3

Ion and Electron Beam Induced Luminescence οf Rare Earth Doped YAG Crystals

88%

Gawlik G., Sarnecki J., Jóźwik I., Jagielski J., Pawłowska M.

Acta Physica Polonica A

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2011

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vol. 120

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issue 1

181-183

EN

The aim of this work was the evaluation of ion-beam induced luminescence for the characterization of luminescent oxide materials containing rare earth elements. The yttrium aluminium garnet epilayers doped with Nd, Pr, Ho, and Tm atoms were used. The ion-beam induced luminescence spectra were excited using 100 keV H_2^{+} ion beam and were recorded in the wavelengths ranging from 300 nm up to 1000 nm. The separate parts of the surface of the same samples were used for ion-beam induced luminescence and cathodoluminescence experiments. Cathodoluminescence spectra have been recorded in the range from 370 nm up to 850 nm at 20 keV e-beam in scanning electron microscope equipped with a grating spectrometer coupled with a photomultiplier. The observed narrow ion-beam induced luminescence lines can be ascribed to the well known radiative transitions in the rare-earth ions in the YAG crystals. The cathodoluminescence spectra reveal essentially the same emission lines as ion-beam induced luminescence. The decrease of the ion-beam induced luminescence lines intensity has been observed under the increasing ion fluences. The ion-beam induced luminescence may be used for characterization of transparent luminescent materials as an alternative method for cathodoluminescence and can be especially useful for observation of ion-beam damage formation in crystals.

4

Damage Accumulation in Nuclear Ceramics

76%

Thomé L., Moll S., Jagielski J., Debelle A., Garrido F., Sattonnay G.

Acta Physica Polonica A

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2011

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vol. 120

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issue 1

7-12

EN

Ceramics are key engineering materials in many industrial domains. The evaluation of radiation damage in ceramics placed in a radiative environment is a challenging problem for electronic, space and nuclear industries. Ion beams delivered by various types of accelerators are very efficient tools to simulate the interactions involved during the slowing-down of energetic particles. This article presents a review of the radiation effects occurring in nuclear ceramics, with an emphasis on new results concerning the damage build-up. Ions with energies in the keV-GeV range are considered for this study in order to explore both regimes of nuclear collisions (at low energy) and electronic excitations (at high energy). The recovery, by electronic excitation, of the damage created by ballistic collisions (swift heavy ion beam induced epitaxial recrystallization process) is also reported.

5

Mutation of the MYH7 gene in a child with hypertrophic cardiomyopathy and Wolff-Parkinson-White syndrome

64%

Bobkowski W., Sobieszczanska M., Turska-Kmiec A., Nowak A., Jagielski J., Gonerska M., Lebioda A., Siwinska A.

Journal of Applied Genetics

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2007

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vol. 48

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issue 2

185-188

EN

Familial hypertrophic cardiomyopathy (HCM) displays autosomal dominant inheritance with incomplete penetration of defective genes. Data concerning the familial occurrence of ventricular preexcitation, i.e. Wolff-Parkinson-White (WPW) syndrome, also indicate autosomal dominant inheritance. In the literature, only a gene mutation on chromosome 7q3 has been described in familial HCM coexisting with WPW syndrome to date. The present paper describes the case of a 7-year-old boy with HCM and coexisting WPW syndrome. On his chromosome 14, molecular diagnostics revealed a C 9123 mutation (arginine changed into cysteine in position 453) in exon 14 in a copy of the gene for beta-myosin heavy chain (MYH7). It is the first known case of mutation of the MYH7 gene in a child with both HCM and WPW. Since no linkage between MYH7 mutation and HCM with WPW syndrome has been reported to date, we cannot conclude whether the observed mutation is a common cause for both diseases, or this patient presents an incidental co-occurrence of HCM (caused by MYH7 mutation) and WPW syndrome.

6

Magnetotransport through Nanoconstriction in Ferromagnetic Semiconductor (Ga,Mn)As

64%

Figielski T., Wosiński T., Pelya O., Sadowski J., Morawski A., Mąkosa A., Dobrowolski W., Jagielski J., Wróbel J.

Acta Physica Polonica A

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2003

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vol. 103

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issue 6

525-531

EN

We studied narrow (submicron) constrictions in the layers of ferromagnetic semiconductor (Ga,Mn)As. We have demonstrated a contribution of the quantum localization effects to the magnetoresistance of the constricted samples. We have also found a negative contribution of a domain wall trapped in the constriction to the resistance, due presumably to the erasing of the localization effects by the domain wall.

7

The Influence of He^+ Ion Bombardment on Magnetic Properties of NiFe/Au/Co/Au Multilayers

64%

Kuświk P., Szymański B., Urbaniak M., Stobiecki F., Sveklo I., Kisielewski J., Maziewski A., Jagielski J.

Acta Physica Polonica A

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2009

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vol. 115

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issue 1

352-354

EN

The influence of He^+ ion bombardment on magnetoresistance, magnetization reversal and domain structure of sputtered (Ni_{80}Fe_{20}(2 nm)/Au(2 nm)/Co(0.6 nm)/Au(2 nm))_{10} multilayers was investigated. The samples were bombarded using He^+(30 keV) ions with fluences D varied from 10^{13} to 3×10^{16} He^+/cm^{2}. With increasing D the following changes in magnetic properties were observed: (i) exponential decay of the saturation field of Co layers, (ii) progressive decrease in magnetoresistance as a result of degradation of Co layers perpendicular anisotropy, (iii) linear decrease in stripe domain period with log(D).

8

Analysis of Crystal Lattice Deformation by Ion Channeling

52%

Jóźwik P., Sathish N., Nowicki L., Jagielski J., Turos A., Kovarik L., Arey B., Shutthanandan S., Jiang W., Dyczewski J., Barcz A.

Acta Physica Polonica A

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2013

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vol. 123

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issue 5

828-830

EN

A model of dislocations has been developed for the use in Monte Carlo simulations of ion channeling spectra obtained for defected crystals. High resolution transmission electron microscopy micrographs show that the dominant type of defects in the majority of ion irradiated crystals are dislocations. The RBS/channeling spectrum is then composed of two components: one is due to direct scattering on randomly displaced atoms and the second one is related to beam defocussing on dislocations, which produce predominantly crystal lattice distortions, i.e. bent channels. In order to provide a correct analysis of backscattering spectra for the crystals containing dislocations we have modified the existing Monte Carlo simulation code "McChasy". A new version of the code has been developed by implementing dislocations on the basis of the Peierls-Nabarro model. Parameters of the model have been determined from the high resolution transmission electron microscopy data. The newly developed method has been used to study the Ar-ion bombarded SrTiO_3 samples. The best fit to the Rutherford backscattering/channeling spectra has been obtained by optimizing the linear combination of two kinds of defects: displaced atoms and bent channels. The great virtue of the Monte Carlo simulation is that unlike a traditional dechanneling analysis it allows quantitative analysis of crystals containing a mixture of different types of defects.

9

Effect of Grain Size on Mechanical Properties of Irradiated Mono- and Polycrystalline MgAl_2O_4

52%

Jagielski J., Piatkowska A., Aubert P., Labdi S., Maciejak O., Romaniec M., Thomé L., Jozwik I., Debelle A., Wajler A., Boniecki M.

Acta Physica Polonica A

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2011

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vol. 120

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issue 1

118-121

EN

The influence of the size of crystalline regions on mechanical properties of irradiated oxides has been studied using a magnesium aluminate spinel MgAl_2O_4. The samples characterized by different dimensions of crystalline domains, varying from sintered ceramics with grains of few micrometers in size up to single crystals, were used in the experiments. The samples were irradiated at room temperature with 320 keV Ar^{2+} ions up to fluences reaching 5 × 10^{16} cm^{-2}. Nanomechanical properties (nanohardness and Young's modulus) were measured by using a nanoindentation technique and the resistance to crack formation by measurement of the total crack lengths made by the Vickers indenter. The results revealed several effects: correlation of nanohardness evolution with the level of accumulated damage, radiation-induced hardness increase in grain-boundary region and significant improvement of material resistance to crack formation. This last effect is especially surprising as the typical depth of cracks formed by Vickers indenter in unirradiated material exceeds several tens of micrometers, i.e. is more than hundred times larger than the thickness of the modified layer.

Refine search results

Effect of Temperature on the Ion Beam Induced Luminescence of Oxide Powders Doped with Rare Earth Elements

Structural and Functional Properties of Ion Beam Modified Elastomers

Ion and Electron Beam Induced Luminescence οf Rare Earth Doped YAG Crystals

Damage Accumulation in Nuclear Ceramics

Mutation of the MYH7 gene in a child with hypertrophic cardiomyopathy and Wolff-Parkinson-White syndrome

Magnetotransport through Nanoconstriction in Ferromagnetic Semiconductor (Ga,Mn)As

The Influence of He^+ Ion Bombardment on Magnetic Properties of NiFe/Au/Co/Au Multilayers

Analysis of Crystal Lattice Deformation by Ion Channeling

Effect of Grain Size on Mechanical Properties of Irradiated Mono- and Polycrystalline MgAl_2O_4