Applications of the Cracow X-ray microprobe in tomography

A nuclear microprobe at the IFJ PAN in Cracow has found numerous applications in different fields of research, mostly in biophysics, medical sciences, geology, and material research. In order to extend the research possibilities, a new X-ray microprobe was constructed. This new microprobe consists of three experimental lines dedicated to: (i) X-ray irradiation of biological specimens, (ii) elemental analysis of samples by micro X-ray fluorescence or total reflection X-ray fluorescence methods and (iii) computer microtomography. In this paper the computer microtomography line was described. The line consists of an open type Hamamatsu L9191 X-ray tube with microfocusing to about 2 μm, a high resolution X-ray sensitive CCD camera, and a precise goniometer composed of six piezoelectric motors. Depending on the required X-ray energy, the Hamamatsu tube is used with Ti, Mo, Ag, or W targets. A small focus size and short focus-to-object distance enable to obtain images of samples with a magnification of more than 1000× and resolution of the order of 2 μm. The computer microtomography measurements are carried out using home developed codes combined with commercial software. Details of the microprobe construction and preliminary results of the computer microtomography experiments are presented

Preliminary investigations of elemental content, microporosity, and specific surface area of porous rocks using PIXE and X-ray microtomography techniques

Determination of physical properties of porous geological materials is of great importance for oil industry. The knowledge of rocks properties is usually obtained from porosity studies such as pore size distribution, specific surface area determination, and hydrodynamic permeability calculations. This study describes determination of elemental composition and measurements of the particular physical properties of geological samples (porous sandstone rocks) by means of the nuclear and X-ray microprobes at the Institute of Nuclear Physics, Polish Academy of Sciences in Kraków, Poland. The special emphasis has been put on the computed microtomography method. Measurements have been carried out in close cooperation with Department of Geophysics, FGGEP AGH in Kraków, Poland. Chemical composition of the Rotliegend sandstone rock samples (few millimeters diameter), extracted from a borehole at 2679.6 m, 2741.4 m and 2742.4 m depth have been investigated using the 2.2 MeV proton beam (proton induced X-ray emission technique). Next, measurements of the porosity and the specific surface area of the pore space have been carried out using the X-ray microtomography technique. Basing on microtomographic data obtained with the high spatial resolution, simulations of the fluid dynamic in the void space of porous media have been carried out. Lattice Boltzmann method in the 3DQ19 geometrical model has been used in order to predict the hydraulic permeability of the media. In order to avoid viscosity-permeability dependence the multiple-relaxation-time model with half-way bounce back boundary conditions has been used. Computing power-consuming processing has been performed with the use of modern grid infrastructure

Electrostatically-induced strain of graphene on GaN nanorods

Few-layer graphene deposited on semiconductor nanorods separated by undoped spacers has been studied in perspective for the fabrication of stable nanoresonators. We show that an applied bias between the graphene layer and the nanorod substrate affects the graphene electrode in two ways: 1) by a change of the carrier concentration in graphene and 2) by inducing strain, as demonstrated by the Raman spectroscopy. The capacitance of the investigated structures scales with the area of graphene in contact with the nanorods. Due to the reduced contact surface, the efficiency of graphene gating is one order of magnitude lower than for a comparable structure without nanorods. The shift of graphene Raman modes observed under bias clearly shows the presence of electrostatically-induced strain and only a weak modification of carrier concentration, both independent of number of graphene layers. A higher impact of bias on strain was observed for samples with a larger contact area between the graphene and the nanorods which shows perspective for the construction of sensors and nanoresonator devices

Stressful life events and coping styles and the intensity of anorectic readiness syndrome in young women

Celem badań było zbadanie zależności pomiędzy natężeniem syndromu gotowości anorektycznej u młodych dorosłych kobiet, a ilością stresujących zdarzeń życiowych, oceną ich przykrości, a także stylem radzenia sobie ze stresem, cechującym osoby badane. Oczekiwano, że osoby, które przeżyły więcej stresujących zdarzeń życiowych oraz oceniają je jako bardziej przykre wykażą większe natężenie syndromu gotowości anorektycznej, a także, że osoby preferujące zadaniowy i unikowy styl w formie poszukiwania kontaktów towarzyskich wykażą niższy poziom syndromu gotowości anorektycznej, a osoby cechujące się stylem emocjonalnym i unikowym w formie angażowania się w czynności zastępcze wykażą niższy poziom syndromu gotowości anorektycznej. Osoby badane wypełniły kwestionariusz SGA-12, CISS, a także kwestionariusz dotyczący przeżytych stresujących zdarzeń życiowych. Przeprowadzono analizę regresji wielokrotnej metodą wprowadzania. Wyniki wskazują na brak zależności między ilością, oceną przykrości stresujących zdarzeń życiowych oraz stylem zadaniowym a natężeniem SGA i na istnienie zależności między stylem emocjonalnym, unikowym w formie poszukiwania kontaktów towarzyskich i angażowania się w czynności zastępcze, a natężeniem SGA.The aim of the study was to investigate the relationship between the intensity of anorectic readiness syndrome (ARS) in young adult women and the number of stressful life events (SLE), assessment of their unpleasantness, as well as the style of coping with stress. It was expected that people who experienced more SLE and rated them as more unpleasant would show a greater intensity of ARS, and that those who prefer task-oriented and avoidance-style in the form of seeking social contacts would show a lower level of ARS, and people with an emotional and avoidance-style in the form of engaging in substitute activities will show a lower level of ARS. Subjects completed the SGA-12, CISS and stressful life events questionnaire. Multiple regression analysis was performed. The results indicate a lack of correlation between the number, assessment of unpleasantness of SLE and task-oriented and the intensity of ARS and the existence of a relationship between the emotional-oriented, avoidance in the form of seeking social contacts and engaging in substitute activities, and the intensity of ARS

Interferometry correlations in central p+Pb collisions

Abstract We present results on interferometry correlations for pions emitted in central p+Pb collisions at $$\sqrt{s_{NN}}=5.02~\hbox {TeV}$$ sNN=5.02TeV in a $$3+1$$ 3+1 -dimensional viscous hydrodynamic model with initial conditions from the Glauber Monte Carlo model. The correlation function is calculated as a function of the pion pair rapidity. The extracted interferometry radii show a weak rapidity dependence, reflecting the lack of boost invariance of the pion distribution. A cross term between the out and long directions is found to be nonzero. The results obtained in the hydrodynamic model are in fair agreement with recent data of the ATLAS Collaboration

Preliminary Investigations of Elemental Content, Microporosity, and Specific Surface Area of Porous Rocks Using PIXE and X-ray Microtomography Techniques

Determination of physical properties of porous geological materials is of great importance for oil industry. The knowledge of rocks properties is usually obtained from porosity studies such as pore size distribution, specific surface area determination, and hydrodynamic permeability calculations. This study describes determination of elemental composition and measurements of the particular physical properties of geological samples (porous sandstone rocks) by means of the nuclear and X-ray microprobes at the Institute of Nuclear Physics, Polish Academy of Sciences in Kraków, Poland. The special emphasis has been put on the computed microtomography method. Measurements have been carried out in close cooperation with Department of Geophysics, FGGEP AGH in Kraków, Poland. Chemical composition of the Rotliegend sandstone rock samples (few millimeters diameter), extracted from a borehole at 2679.6 m, 2741.4 m and 2742.4 m depth have been investigated using the 2.2 MeV proton beam (proton induced X-ray emission technique). Next, measurements of the porosity and the specific surface area of the pore space have been carried out using the X-ray microtomography technique. Basing on microtomographic data obtained with the high spatial resolution, simulations of the fluid dynamic in the void space of porous media have been carried out. Lattice Boltzmann method in the 3DQ19 geometrical model has been used in order to predict the hydraulic permeability of the media. In order to avoid viscosity-permeability dependence the multiple-relaxation-time model with half-way bounce back boundary conditions has been used. Computing power-consuming processing has been performed with the use of modern grid infrastructure