Documents
The use of the NPI infrastructure and of the funding project must be properly mentioned in publications (for example: Measurements were carried out at the CANAM infrastructure of the NPI CAS Rez supported through MEYS project No. LM2015056)
The scientific results of the experiments that were carried out at CANAM laboratories are available on request from the Instruments Responsible.
Semináře
10. 12. 2015, 14.30, In-situ study of high temperature demage mechanism of fatigued nickel superalloy
MARTIN PETRENEC
Institute of Physics of Materials of the CAS, Prague, Czech Republic
Thursday, 10. 12. 2015, 14:30, conference room of the Neutron Physics Laboratory (F2), NPI CAS Rez
10. 12. 2015, 14.00, In-situ recrystallization studies of FCC metals
MARTIN PETRENEC
Institute of Physics of Materials of the CAS, Prague, Czech Republic
Thursday, 10. 12. 2015, 14:00, conference room of the Neutron Physics Laboratory (F2), NPI CAS Rez
2. 12. 2015, 11.30, Detailed study of the tokamak plasma exposed carbon tails by IBA methods
VLADIMÍR HAVRÁNEK
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Wednesday, 2. 12. 2015, 11:30, conference room of the Laboratory of Tandetron, NPI CAS Rez
2. 12. 2015, 11.00, Decomposition and analysis of hard and moderate ductile MoBC coatings by pulsed DC sputtering
VRATISLAV PEŘINA
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Wednesday, 2. 12. 2015, 11:00, conference room of the Laboratory of Tandetron, NPI CAS Rez
2. 12. 2015, 10.30, Application of Ion Beam Analysis Methods within the laser-matter interaction research
MARIAPOMPEA CUTRONEO
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Wednesday, 2. 12. 2015, 10:30, conference room of the Laboratory of Tandetron, NPI CAS Rez
2. 12. 2015, 10.00, Micro-patterns fabricationms using focused beam litography
MARIAPOMPEA CUTRONEO
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Wednesday, 2. 12. 2015, 10:00, conference room of the Laboratory of Tandetron, NPI CAS Rez
26. 11. 2015, 11.00, Structural and optical properties of metal ion implanted GaN
ANNA MACKOVÁ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Thursday, 26. 11. 2015, 11:00, conference room of the Laboratory of Tandetron, NPI CAS Rez
26. 11. 2015, 10.30, Compositional structural and optical changes of heavy ions irradiated polyimide
ROMANA MIKŠOVÁ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Thursday, 26. 11. 2015, 10:30, conference room of the Laboratory of Tandetron, NPI CAS Rez
26. 11. 2015, 10.00, The stopping power and energy straggling of the energetic C and O ions in polyimide
ROMANA MIKŠOVÁ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Thursday, 26. 11. 2015, 10:00, conference room of the Laboratory of Tandetron, NPI CAS Rez
23. 11. 2015, 11.30, Deconvolution method for near surface residual strain gradients measured by neutron diffraction
JAN ŠAROUN
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Monday, 23. 11. 2015, 11:30, conference room of the Neutron Physics Laboratory (F2), NPI CAS Rez
23. 11. 2015, 11.00, Evaluation of anisotropic small-angle scattering data from metastable beta-Ti alloys
PAVEL STRUNZ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Monday, 23. 11. 2015, 12:30, conference room of the Neutron Physics Laboratory (F2), NPI CAS Rez
23. 11. 2015, 10.30, Formation and dissolution of gamma' pracipitates in IN792 superalloy at elevated temperatures
PAVEL STRUNZ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Monday, 23. 11. 2015, 11:30, conference room of the Neutron Physics Laboratory (F2), NPI CAS Rez
28. 7. 2015, 11.30, Charakterizace nanostruktur připravených iontovou implementací
HANA PUPÍKOVÁ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Tuesday, 28. 7. 2015, 11:30, conference room of the Laboratory of Tandetron, NPI CAS Rez
28. 7. 2015, 10.30, Kovové nanočástice v polymerech připravené iontovou implementací a jejich charakterizace
PETR MALINSKÝ
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Tuesday, 28. 7. 2015, 10:30, conference room of the Laboratory of Tandetron, NPI CAS Rez
17. 4. 2015, 11.00, Phase evolution in mixture of cobalt and fullerene
INNA LAVRENTEVA
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Tuesday, 17. 4. 2015, 11:00, conference room of the Laboratory of Tandetron, NPI CAS Rez
17. 4. 2015, 10.30, Response of surface morphology in cobalt-fullerene mixture film upon variation of metal content
INNA LAVRENTEVA
Nuclear Physics Institute of the CAS, Rez, Czech Republic
Tuesday, 17. 4. 2015, 10:30, conference room of the Laboratory of Tandetron, NPI CAS Rez
25. 4. 2014, 10.00, Utilization of Atomic Forces for Surface Imaging
INNA LAVRENTEVA
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Friday, 25. 4. 2014, 10:00, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
Atomic force microscopy (AFM) is a unique method of surface characterization, which is widely used at present in the nanoscience-related researches. Success of the researches strongly depends on the proper application and correct understanding the method principles and outputs. This report is a brief demonstration of the most important items related to the AFM basis, functionality and application potential. The functional opportunities of the method are shown through presentation of the main operating modes and specific setups, which can yield the persuasive information about structure and properties of the surface. Several expressive examples of the AFM application, obtained with the NTEGRA Aura AFM complex (NPI AS CR), allow to discern important role and perspectives of the method in development of the advanced nanomaterials.
25. 4. 2014, 10.30, Nuclear Track-Based Biosensors with the Enzyme Laccase
JIŘÍ VACÍK
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Friday, 25. 4. 2014, 10:30, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
A new type of biosensors for detecting phenolic compounds is presented. These sensors consist of thin polymer foils with laccase-clad etched nuclear tracks. The presence of suitable phenolic compounds in the sensors leads to the formation of enzymatic reaction products in the tracks, which differ in their electrical conductivities from their precursor materials. These differences correlate with the concentrations of the phenolic compounds. Corresponding calibration curves have been established for a number of compounds. The thus produced sensors are capable to cover between 5 and 9 orders of magnitude in concentration - in the best case down to some pico-moles. The sensor's detection sensitivity strongly depends on the specific compound, it is highest for cafeic acid and acid blue 74, followed by ABTS and ferulic acid.
28. 2. 2014, 10.00, Numerous impact of energetic fullerene clusters on silicon crystal surface: modification features
VASYL LAVRENTEV
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Friday, 28. 2. 2014, 10:30, conference room of the Neutron Physics Laboratory (building F-II), NPI ASCR Rez
Abstract
Interaction of energetic clusters with solid surface attracts enhanced attention in desire to utilize the interaction effects for controlled modification of surface structure and properties. In this study we have tested this potential of cluster ion bombardment (CIB) carrying out irradiation of silicon crystal surface by monoenergetic beams of the fullerene cluster ions. The samples of Si(100) were irradiated by C60 cluster ions with energies of 200 keV and 400 keV under normal ion incidence to enhanced fluences (from 5×1013 to 7×1014 ions/cm2) implying uniform modification of the surface. Several aspects of Si modification under the CIB (surface nanostructuring, creation of the disordered layer, and surface sputtering) have been analyzed.
28. 2. 2014, 10.30 - Nanostructure and Nanomagnetism in Dilute and Supersaturated Cobalt-Fullerene Mixed Systems
VASYL LAVRENTEV
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Friday, 28. 2. 2014, 10:30, conference room of the Neutron Physics Laboratory (building F-II), NPI ASCR Rez
Abstract
Two kinds of the Co-C60 thin films including respectively low (LM) and high (HM) content of Co were fabricated on clean Si(100) substrates using method of simultaneous deposition. Structure and composition of the deposited films were analyzed using atomic force microscopy, Rutherford backscattering, and Raman spectrometry. The analysis confirmed formation of the homogeneous structure with approximate formula of Co0.3C60 in the LM films and the heterogeneous structure in the HM films with estimated composition of Co27C60. Study of magnetization of the films carried out with superconducting quantum interference device in the temperature range of 5 K to 300 K revealed superparamagnetic behaviour of the HM films proving formation of the small Co clusters in this composition. On the other hand the LM films revealed ferromagnetic behaviour suggesting formation of the magnetic Co1C60 compounds.
28. 2. 2014, 11.00, Free volume distribution of the stressed hybrid films analyzed by profiling of the Hg and Li diffusion markers
JIŘÍ VACÍK
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Friday, 28. 2. 2014, 11:00, conference room of the Neutron Physics Laboratory (building F-II), NPI ASCR Rez
Abstract
Thin hybrid films of the organic fullerenes (C60) and transition metals (Ni, Ti, Co, etc.) have been synthesized by co-evaporation or alternating deposition of the fullerenes and metal components at different deposition kinetics (deposition rates, temperatures of the substrates, etc.). As a result, thin film mixtures and multilayers with various nano-structures were prepared. The structural forms, stability and thermal response of the composites were inspected using the ion and neutron beam analytical techniques (e.g., Rutherford Backscattering/Channeling, Elastic Recoil Detection Analysis and Thermal Neutron Depth Profiling), and other complementary methods (e.g., micro-Raman spectroscopy, Scanning Electron Microscopy). It has been found that the synthesis of the immiscible organic-metallic phases leads to the (nano)structures exhibiting a variety of forms that strongly depend on the deposition kinetics. As-deposited, the composite films are usually internally stressed with free volume defects. The evolution of the stress relaxation, induced by thermal annealing (or energetic ion or laser beams) can, advantageously, be studied by the free volume distribution analysis. If the free volume is marked by a suitable (well-analyzable) diffusion marker, then the depth profiles of the marker copy the depth distributions of the free volume. In the paper, highly mobile free volume markers, Hg vaporized atoms and Li+ ions (from the 5 M/l LiCl water bath) have been utilized. The markers indiffused into the thin films of the hybrids and occupied in the first place the free volume defects. The controlled thermal annealing of the composites triggered a process of the gradual phase separation and structural stress relaxation. This also caused an alteration of the structure and, consequently, the free volume distribution that the Hg and Li diffusion markers could occupy. It has been found that the marker distributions of the as-deposited films follow mainly the character of the C60 component distribution. After annealing of the hybrid systems at elevated temperatures, however, the marker profiles decrease dramatically - suggesting a significant drop-off of the free volume concentration, perhaps due to the formation of the spatially compact a-C clusters.
13. 12. 2013, High intensity laser for Ta and Ag implantation into different kinds of stubstrates for plasma diagnostics
MARIAPOMPEA CUTRONEO
Nuclear Physics Institute of the ASCR, Rez, Czech Republic,
INFN - Laboratori Nazionali del Sud, Catania, ITALY
Friday, 13. 12. 2013, 10:30, conference room of the Neutron Physics Laboratory (building F-II), NPI ASCR Rez
Abstract
The ongoing development of modified thin targets are allowing exploration of new regime of acceleration (Target Normal Sheath Acceleration) by using laser with intensity up to 1016 W/cm2.
The production of ion beams from laser-generated plasma is an important aspect of the recent research activities because 1-10 MeV/charge state ions, find many applications in different scientific fields such as Bio-medicine, nuclear physics and microelectronic. In order to generate plasma with high charge states and ion energy, it is necessary to enhance the plasma Coulomb acceleration by using thin targets able to absorb high laser energy. The presence of metallic nanoparticles in a target, for example, may generate Surface Plasmon Resonance with high absorbent component. We realized study of ion implantation into the different substrates using high intensity laser. At PALS laboratory in Prague a high intensity laser, operating in single pulse at 1315 nm, 300 ps pulse duration and 1015 W/cm2 intensity, was employed to produce non-equilibrium plasma accelerating ions. The laser impinges against a thick primary target of Ta or Ag, generating plasma and the emitted ions can be implanted on substrates exposed to the plasma. The ions were implanted in polyethylene, in silicon and in metallic substrates (Al, Cu), at energies of the order of tens keV per charge state. The substrates were chosen with a different structure, composition and different mechanical properties to get information about the plasma generated ion modification. The implantation was obtained after 12 laser shots irradiating the Ag and Ta targets in order to increase the implantation fluencies. Rutherford Backscattering Spectrometry (RBS) was used to characterize the elemental composition changes in the modified layer and to provide the implanted ion depth profiling. XPS analysis serves for the study of chemical bonds modification in the implanted layer. The depth profiles of the implanted ions and their energy distribution was investigated. The depth distributions of implanted Ta and Ag ions were compared with the theoretical one’s achieved by using SRIM - 2008 simulation code. In case of implanted polyethylene the structural properties were studied using UV VIS spectroscopy and morphology of possibly coalesced nano-particles was studied using TEM. Results concerning the energy distribution of the implanted ions were compared with measurements obtained by using ion collectors and ion energy analyzer.
13. 11. 2013, Measurement of excitation functions and production of medical radionuclides on the cyclotron U-120M
ONDŘEJ LEBEDA
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Wednesday, 13. 11. 2013, Heavy Ion Laboratory, Warszaw University, Warszaw, POLAND
Abstract
Cyclotron U-120M at the Nuclear Physics Institute AS CR is rather versatile instrument for production of many radionuclides and in general for measurement of excitation functions induced by protons, deuterons, 3He and α-particles. Recently, we reported for the first time cross-sections for the following nuclear reactions:
- a) 231Pa(p,2n) and 231Pa(d,3n) for production of 230U as potentially interesting radionuclide for alpha radio-immunotherapy;
- b) natNd(p,x) resulting in 141Pm, 143Pm, 144Pm, 146Pm, 148Pm, 148mPm, 149Pm, 150Pm, 140Nd, 141Nd, 147Nd, 149Nd, 138mPr, 139Pr, 142Pr and 139Ce from which longer-lived 143Pm, 144Pm, 146Pm, 148mPm, 139Ce are relevant for experiments searching for double beta decay;
- c) 3He induced reactions on monoisotopic elements. We also obtained primary data for cyclotron production of 99mTc as an alternative to reactor-produced 99Mo (excitation functions, yields and achievable radionuclidic purity).
Cyclotron U-120M is currently used for production of various radionuclides on solid, liquid and gaseous targets of our own design and construction, too. Besides routine production of 18F and 81Rb, we have been focused on non-conventional positron emitters like 124I, 86Y, 68Ga, 61,64Cu etc. and also on a few radionuclides for SPECT imaging or therapy (123I, 211At). Occasionally, cyclotron is used also on preparing specialized calibration sources like 83Rb for the KATRIN and XENON projects or 56Co and 90Nb emitting high-energy gammas. Our activities are going to be extended thanks to purchase of the cyclotron TR24 that should be put in operation in the beginning of the year 2015.
7. 11. 2013, 14:30, Magnetic steel health monitoring
EVANGELOS HRISTOFOROU
National Technical University of Athens, GREECE
Thursday, 7. 11. 2013, conference room of the Neutron Physics Laboratory (building F-II), NPI ASCR Rez
2. 10. 2013, 10.00, Comparison of structural changes and optical properties of LiNbO3, Al2O3 and ZnO after Er implantation
ANNA MACKOVÁ
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Wednesday, 2. 10. 2013, 10:00, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
The structural as well as compositional changes of LiNbO3, Al2O3 and ZnO crystals, implanted with Er ions at 190 keV with fluences of 1.0x1016 cm−2 into Z-cuts <0001> have been reported in this contribution. Post–implantation annealing at 1000 °C in oxygen atmosphere was also done. The chemical compositions and erbium depth concentration profiles of implanted layers were studied by Rutherford Back-Scattering spectrometry (RBS) and compared to SRIM 2008 simulations. The same value of maximal erbium concentration (up to 2 at. %) was observed in 40 nm depth for all crystals. Surface changes caused by ion implantation were characterized by AFM. Structural properties of the prepared layers were characterized by RBS/channelling. The relative numbers of disordered atoms in prepared implanted layers were compared with each other and discussed for various crystals. It has been found, that Er is positioned in LiNbO3 and in sapphire preferably in interstitial positions contrary to ZnO, where larger amount of Er (about 45%) was placed in substitutional positions. The Er position in host matrix was substantially influenced by the annealing procedure. Since we are interested in relationships between structural changes and optical properties, the Er luminescence properties were measured in the region 1400-1600 nm. The positive effect of post-implantation annealing on luminescence properties caused by structure recovery will be shown as well as discussed for the various crystals.
2. 10. 2013, 10.30, Characterization of nano-structures prepared by Fe+ low energy ion implantation
PETR MALINSKÝ
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Wednesday, 2. 10. 2013, 10:30, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
The implantation of ions with energies below 100 keV to very high fluences into polymers leads to the formation of a metal-rich, carbonized layer on the polymer surface with interesting physico-chemical properties. The implanted metal atoms tend to agglomerate which leads to the creation of nanoparticles with specific electromagnetic and optical properties. The study of the electrical properties of the metal/polymer composites is of interest for a fundamental reason. High fluence implantation of metal ions can be used to fabricate metal-doped polymer films, which are applicable in electronics due to their high electric conductivity and field electron emission capacity. Polyimide (PI), polyetheretherketone (PEEK), and polyethyleneterephtalate (PET) were implanted by 80 keV Fe+ ions at room temperature at fluences (1x1016 – 1.0x1017) cm–2 and annealed at temperatures below and close to Tg up to 300°C. Changes in the chemical composition and implanted Fe depth profiles in polymers induced by high fluence metal ions irradiation and additional annealing have been studied using RBS, ERDA and XPS techniques. Fe depth profiles determined by RBS are compared to SRIM 2008 calculations. Surface morphology of implanted polymers was characterized using AFM. Implanted Fe atoms tend to aggregate into nano-particles, the size and distribution of which was determined from TEM micrographs and using image analysis. Optical properties and structural changes of the modified polymers were characterized by the UV–vis spectroscopy. The changes in the polymer sheet resistance of the implanted and annealed samples were measured by standard two-point technique.
2. 10. 2013, 11.00, Stopping powers and energy loss straggling of heavy ions in polymer foils
ROMANA MIKŠOVÁ
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Wednesday, 2. 10. 2013, 11:00, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
Stopping powers and energy loss straggling of heavy ions in polymer foils, R. Miksova, A. Mackova, P. Malinsky, V. Hnatowicz, P. Slepicka, The 11th European Conference on Accelerators in Applied Research and Technology in Namur, Belgium, from 8 to 13 September 2013. In this study, stopping powers and energy loss straggling of 7Lin+, 12Cn+ and 16On+ heavy ions crossing through thin polyetheretherketone (PEEK) and polyethylene terephthalate (PET) foils have been measured in the energy range 9.4 - 11.2 MeV using the indirect transmission method. The details of experimental setup combination of Rutherford backscattering spectrometry and transmission method are described. Advantages of such method application on energy losses measurement are discussed. Composition and Au layer thickness of the scattering target were determined using RBS. Thickness composition and uniformity of the investigated polymer foils were characterised by RBS, ERDA and AFM. Weighting method was used for independent thickness determination of the foils. Back-scattered ion spectra recorded under the scattering angle 170° by Ultra Ortec detector with and without foil placed before detector were evaluated by code ITAP, which was developed at our laboratory. We obtained the stopping powers of 7Lin+, 12Cn+ and 16On+ in PEEK and PET and compared the experimental results to the theoretical predictions calculated by SRIM-2008 and MSTAR codes. The energy loss straggling in polymeric foils has been compared to the corresponding computed values based on theoretical formulations introduced by Bohr, Lindhard-Scharff and Bethe-Livingston.
17. 9. 2013, 10.00, Study of the Structural and Magnetic Properties of ZnO Implanted by Gd IonsLaboratory of Tandetron, NPI ASCR Rez
ANNA MACKOVÁ
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Thursday, 17. 9. 2013, 10:00, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
We report the structural, surface morphology and magnetic properties of ZnO single crystals implanted with Gd ions at 200 keV up to fluence 5×1015 cm−2 and subsequent annealing was applied at 800 °C in various atmospheres. The chemical composition and concentration profiles of ion-implanted layers were studied by Rutherford Back-Scattering spectrometry (RBS) and compared to SRIM 2008 simulations. RBS shows that after implantation the broader Gd profiles were found than simulated by SRIM and after annealing the Gd profiles are narrower and concentration maximum is in a good agreement with SRIM simulation. The structural properties of the layers were characterized by RBS channelling which shows the decreased relative number of disordered atoms in implanted layer after the annealing procedure. Simultaneously amount of Gd in substitutional positions is after the annealing procedure decreased. AFM analysis was used to determine the surface morphology changes after implantation and annealing procedures. Magnetic properties were studied using SQUID magnetometer. The as implanted sample exhibits ferromagnetism persisting up to room temperature. The annealing procedure led to the paramagnetic behaviour probably due to the formation of gadolinium oxide nanoclusters. Structural changes were studied by confocal Raman microscopy.
17. 9. 2013, 10.20, The Structural Changes and Optical Properties of LiNbO3 after Er Implantation Using High Ion Fluencies
ANNA MACKOVÁ
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Thursday, 17. 9. 2013, 10:20, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
The structural as compositional changes of LiNbO3 crystal implanted with Er ions at 190 keV with fluences 1x1016 and 5×1016 cm−2 into various crystallographic cuts have been reported here. Post–implantation annealing at 1000°C in oxygen atmosphere was also done. The chemical compositions and erbium depth concentration profiles of implanted layers were studied by Rutherford Back-Scattering spectrometry (RBS) and compared to SRIM 2008 simulations. The results showed that after implantation, Er concentration profiles were found broader than the ones from SRIM simulation in case of the higher implantation fluences. The same value of maximal erbium concentration - up to 8 at % - was observed in the 50 nm depth for all cuts of crystal. It is clear that the observed Er concentration correspond well with the used fluencies. The structural properties of the layers were characterized by RBS/channelling which shows the increased relative number of disordered atoms in implanted layers. Simultaneously, amount of Nb in the surface implanted layer is decreased and surface erosion at highest implantation fluencies were studied using AFM. Since we are interested in relationship between the structural changes and optical properties, the Er luminescence properties were measured in the region 1400-1600 nm. The positive effect of post-implantation annealing to luminescence properties caused by structure recovery was proved. According to our previous results, the influence of various implantation energies to structure changes as well luminescence properties will be discussed.
17. 9. 2013, 10.40, Ion Beam Analysis of Hard Nanocrystalline Zr-B-C-(N) Films Prepared by Pulsed Magnetron Sputtering
VRATISLAV PEŘINA
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Thursday, 17. 9. 2013, 10:40, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
The multicomponent Zr-B-C-N films were prepared using pulsed magnetron co-sputtering of B4CZr target (at 15 % of zirconium in the target erosion area) in Ar-N2 gas mixtures of total pressure of 0.5 Pa at Si or glass substrates at temperature 450oC and at floating potential. A planar unbalanced magnetron was driven by a pulsed dc power supply operating at a repetition frequency of 10 kHz with a fixed 85% duty cycle. High-quality defect-free films, ~ 4 μm thick, with smooth surfaces and good adhesion to substrates at low compressive stresses were produced. Hard (37 GPa) nanocolumnar ZrB2-type films with a very low compressive stress (0.4 GPa), high electrical conductivity (electrical resistivity of 2.3×10-6 Ωm) and high oxidation resistance in air up to 650 °C were prepared in pure argon. Increasing the N2 fraction in the gas mixture resulted in a significant decrease of the film hardness and in a rapid rise in their electrical resistivity and oxidation resistance in air at elevated temperatures due to a growing volume fraction of an amorphous phase with a high content of nitrogen (up to 49 at.%) in the materials. The investigation of the effects of the Ar-N2 gas mixture composition on the evolution of the elemental composition of the Zr-B-C-N films was by using non-destructive nuclear analytical methods: ERDA for hydrogen admixture amount and RBS for other elements. Owing to the presence of Zr, B, C, N as fabricating and O, H, Ar as admixture elements the single RBS spectra are very unreadable due the overlapping signal of all elements. This problem is solved using more non- Rutherford analyses suited for sought after specific elements.
17. 9. 2013, 11.00, Plasma Deposition of Nanocomposite Protective Coatings on Polymer Substrates
VRATISLAV PEŘINA
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Thursday, 17. 9. 2013, 11:00, conference room of the Laboratory of Tandetron, NPI ASCR Rez
Abstract
Transparent thin films with a wide range of mechanical properties were produced from hard inorganic (SiO2 like) to soft polymer-like (SiOxCyHz films) properties just by varying the plasma conditions. At optimum discharge conditions, when the organosilicon dust plasma started to create from the hexamethyldisiloxane/oxygen mixture, the prepared films exhibited nanocomposite structure.
29. 5. 2013, 9.30, Precipitate microstructure evolution in exposed INCONEL superalloy
PAVEL STRUNZ
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Wednesday, 29. 5. 2013, 9:30, conference room of the Neutron Physics Laboratory (building F-II), NPI ASCR Rez
1. 2. 2013, Measurement of excitation functions and production of radionuclides at the Nuclear Physics Institute
Institut für Kernphysik, Westfälische Wilhelms-Universität, Münster, Germany
ONDŘEJ LEBEDA
Nuclear Physics Institute of the ASCR, Rez, Czech Republic
Friday, 1. 2. 2013, Institut für Kernphysik, Westfälische Wilhelms-Universität, Münster, GERMANY
Abstract
Cyclotron U-120M at the Nuclear Physics Institute AS CR is rather versatile instrument for production of many radionuclides and in general for measurement of excitation functions induced by protons, deuterons, 3He and α particles. Recently, several excitation functions were measured here for the first time: a) 231Pa(p,2n) and 231(d,3n) for production of 230U as potentially interesting radio-nuclide for alpha radioimmunotherapy; b) natNd(p,x) resulting in 141Pm, 143Pm, 144Pm, 146Pm, 148Pm, 148Pmm, 149Pm, 150Pm, 140Nd, 141Nd, 147Nd, 149Nd, 138Prm, 139Pr, 142Pr and 139Ce from which longer-lived 143Pm, 144Pm, 146Pm, 148Pmm, 139Ce are relevant for SNO+ experiment; c) 3He induced reactions on monoisotopic elements. The institute was also much involved in obtaining primary production data for cyclotron production of 99mTc as an alternative to reactor-produced 99Mo (excitation functions, yields and achievable radionuclidic purity). Besides that, cyclotron U-120M is currently used for pro-duction of various radionuclides on solid, liquid and gaseous target systems of our own design and construction, including e.g., 83Rb for calibration sources in the KATRIN and XENON projects and medi-cally relevant radionuclides both for research and clinical practice.
3. 7. 2013, 10:30 - Organotin(IV) compounds with C,Y-chelating ligands
PETRA ECORCHARD
ve středu 3. 7. 2013, 10:30, zasedací místnost ONF v budově F-II.
Abstract
Organotin(IV) compounds with C,Y-chelating ligands
PETRA ECORCHARD
Successful research on Trypanocidal activity of organotin(IV) compounds1 appeared in 2003. Organotin(IV) compounds show strong in vitro activity, however, the in vivo activity is still low. One of the possibilities to improve the Trypanocidal activity of organotin compounds with 3-methoxypropyl ligand could be the substitution of chloride atoms. Research interest has been extended to studies of [2-(N,N-dimethylamino)phenyl] diorganotin(IV) acetates substituted with organophosphorus groups in α-position of the acetate ligand. In such type of compounds, the central tin atom could be coordinated via N-atom of C,N-chelating ligand or via P, O or S donor atoms of phosphorus group forming hypervalent organotin(IV) compounds. Thus, they open new synthetic possibilities for the preparation of complexes with transition metals (e.g. Pd, Pt, Rh and Ru), which can be used for homogeneous catalysis.
The coordination behaviour of these compounds has been studied by NMR spectroscopy in coordinating and non-coordinating solvents and IR spectroscopy; CP/MAS NMR spectroscopy has been measured in some cases and, in some selected cases, the single crystal has been refined by single X-ray diffraction studies.
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1. 7. 2013, 10:30 - From Instrumentation to Science
Nadir Aliouane
(Laboratory for Neutron Scattering, Paul Scherrer Institut Villigen, Switzerland)
v pondělí 1.7.2013, 10:30, zasedací místnost ONF v budově F-II .
Abstract
From Instrumentation to Science With the development of the synchrotron facility and laboratory X-ray single crystal diffractometer, the aim of neutron single crystal diffraction (NSCD) is nowadays focused toward solving complex magnetism (unpolarized and polarized neutron scattering) in classical and challenging sample environment (high magnetic field, pressure, He3
dilution temperature).
These targets fix the instrumentation requirement for the development of NSC 4-circles diffractometer like low background (improvement of neutron filter and use of PG analyzer), non magnetic secondary instrument (High magnetic field), large momentum transfer (thermal neutron and large scattering angle) for limited geometry (Horizontal and vertical scattering with cryomagnet) and structural determination, polarized thermal neutron beam for complex and quantum magnetism. All these aspects will be considered for the development concepts of TriCs: Panther, the thermal NSC diffractometer at the SINQ facility (LNS, Paul Scherrer Institut) in the first part of this presentation. Bench mark experiment in correlation with Monte Carlo ray Tracing simulations (Vitess and Mcstas) will be showed.
The second part will center on the scientific achievement on new multiferroic material performed at TriCs. RE+3Mn2O5 compounds with (RE=rare earth:Tb, Y, Dy, Ho, .) are well known materials which exhibits complex magnetic phase transitions[1] and multiferroic properties [2,3]. These systems are magnetically frustrated and it is at the origin of the multiferroic properties. In frustrated antiferromagnet, ferroelectric arises following two main case: magnetostriction of neighboring spins wave [Si.Sj?0] [3] or in cycloidal spin arrangement [4]. The frustration
here have been tuned by exchanging Mn ion by Fe in TbFexMn2-xO5 with x=0.30 and nuclear and magnetic structure have been investigated and be presented.
[1] E. F. Berthaut et al. , Solid. Stat. Comm. 5,25 (1925)
[2] I. Akinobu and K. Kay, Ferroelectrics 169, 75 (1995), N. Hur et al. , Nature 429, 392 (2004).
[3] L. C. Chapon, Phys. Rev. Lett. 96, 976001 (2006).
[4] H. Kimura, J Phys Soc Jpn 76, 074706 (2006).
26. 6. 2013, 10:30 - Structural studies of some functional oxide materials
Charles Hervoches
(Department of Chemistry, Centre for Materials Science and Nanotechnology, University of Oslo, Norway)
ve středu 26.6.2013, 10:30, zasedací místnost ONF v budově F-II.
Abstract
Structural studies of some functional oxide materials Complex oxide materials exhibit a wide range of properties that give rise to a number of applications within future Energy and Information and Communication (IC) technologies. High-temperature oxide ion and proton conductors play important roles in the development of technologies related to efficient and environment-friendly energy production e.g. as electrolytes, electrodes or as membranes for oxygen or hydrogen separation. While applications envisaged for new ferroelectric materials are, for example, capacitors, information storage devices (FERAMs), and high permittivity microwave resonators. A fundamental understanding of such materials demands the use of advanced experimental methods, amongst them neutron diffraction. The presentation will address structure-property relations of a selection of oxide materials with ferroelectric, magnetic, and ionic conduction properties.
24. 4. 2012, 10.30 - Introduction into the semiconductors detectors
Ing. Milos Vidra, CSc.
24. 4. 2012, 10.30, Laboratory of Tandetron
The main operation principles of the semiconductor detectors for X-ray and g - radiation will be presented. The basic physical processes producing free charge carriers in semiconductor detector induced by the radiation in semiconductors (Ge, Si etc.) will be explained and the construction of different types of detectors – the lacks and advantages- will be mentioned.
