Scientific blog
October 2011 
Wednesday, 2 November, 2011, 15:15
Posted by Piotr Bobrowski
This month, due to failure of the microscope, I continued reading literature. Additionally, a scientific cooperation between IMIM and the Foundry Research Institute was established. We are going to conduct some joint experiments. As a part of the project, a first series of samples was recieved from FRI. They were electropolished and, after the microscope was repaired, some EBSD and EDS maps were collected. Now they were sent back to FRI to conduct some further experiments there.
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primary investigation of liquid systems (MTrybula) 
Monday, 31 October, 2011, 17:12
Posted by Marcela Trybula
In October was done:
Oral presentation of master thesis results. The aim of the thesis was to investigate the changes in bond length and order, depending on molecule size and bond location in the chains of polyyne and cumulene. Using the ETS-NOCV method of Mitoraj , bonds in the centre of polyyne and cumulene chains were qualitatively and quantitatively described. Another subject of investigation was influence of change in the length of central bond in the shortest polyyne and cumulene chains on the change of bond orders. DFT/BP calculations carried out in this work allowed to find the length of cumulene chain for which the alternation of bonds reappears. The reappearance of bond alteration is clear for molecules counting more than 104 carbon atoms, which is much more than for similar calculations carried out with SCC-DFTB or DFT/B3LYP methods. Such a result shows a significant quantitative difference between various calculation methods. In spite of these quantitative differences, the results obtained in this work were qualitatively consistent with the results obtained with other methods, e.g. SCC-DFTB, DFT/B3LYP . A significant part of this thesis was the application of ETS-NOCV methodology to obtain quantitative information about the participation of σ and π components in the investigated chemical bonds; this kind of information was inaccessible by other methods of charge and bond order analysis.
Doctoral thesis concerned the description of solution model based on the free volume theory [Lupis,1956], Shimoji [Shimoji,1957]. Form initial theoretical studies come from necessity to define a new factor beta and the configuration entropy can be also developed. Comparing of both ideas, namely Tanaka and PhD student, was shown evidently clear good path of taking measures to extension of applied model in case of simulation the excess thermodynamic functions (Gibbs energy and entropy). Unfortunately, each model has some constraint, which are limited to using for every metallic solutions.

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October 
Saturday, 29 October, 2011, 02:06
Posted by Piotr Drzymala
I made the analysis phase AZ31 magnesium alloy samples with 1.5 micrometer layer of Cr and 1.6 micrometer CrAlN layer. Samples were examined using the technique of grazing incidence diffraction angles for fixed beam radius: 3, 5, 7.5, 10, 12.5 and 15 degrees to the sample surface. In addition, for comparison, were examined in a model of magnesium aluminum and zinc - AZ31. Method of measuring grazing incidence diffraction is a technique that allows the examination of very thin films and coatings that cover some of the interest eg for corrosion protection and improve the quality of the surface.
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Conference report (6-7.10.2011) J.Poplewska 
Monday, 10 October, 2011, 15:23
Posted by Jagoda Poplewska
I attended in ‘Advanced Electron Microscopy Methods Applied to Investigations of Nanomaterials’ in 6-7.10.2011 r., organized by Warsaw University of Technology and Hitachi High-Technologies. During first day I precipitated in lectures:

- ‘Advanced sample preparation technique with the NB5000 for reactive materials’ given by M. Konno;
- ‘Characterization of oxide nanoparticles in ODS ferritic steel’ given by Prof. M. Lewandowska;
- ‘Applying of Cs corrected TEM for structure identification’ given by Prof. P. Dłużewski;
- ‘New instrumentation for high resolution EM’ given by dr. M. Haider;
- ‘First experiences with the HD-2700 at ETH Zurich: an overview from material to life science applications’ given by dr. E. Muller and dr. R. A. Haider;
- ‘Atomic resolution secondary electron imaging with Hitachi HD-2700 aberration corrected STEM’ given by H. Inada;
- ‘Nanoscale imaging via SEM and STEM – background and case studies’ given by dr. T. Płociński;
- ‘Applications of STEM detectors in Scanning Electron Microscopy in materials science’ given by dr. T. Tokarski.
After lectures were provided lab tour.

On second day there were carried workshops – I attended in EBSD research with use SEM Hitachi SU-70.

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M.Gajewska PhD report (September 2011)  
Monday, 10 October, 2011, 11:54
Posted by Marta Gajewska
In September I concentrated on investigating a series of 7475 alloy samples sintered freely in different atmospheres (argon, nitrogen) and at different temperatures (540 - 640oC). Optical microscopy observations and scanning electron microscopy investigations were performed. The lowest pore content was noticed in Ar-atmosphere samples sintered above 600oC (samples sintered under N2 atmosphere had generally more porosity). There was no aluminium nitride phase (in N2- sintered samples) detected using EDS analysis.
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