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Analiza lotnych związków organicznych z powierzchni ludzkiej skóry
No full textZapach ludzkiego ciała jest najbardziej znanym i rozpoznawanym sygnałem świadczącym o ogólnym stanie higieny, jak również o prawidłowości procesów metabolicznych zachodzących w organizmie. Za charakterystyczny i specyficzny dla każdego człowieka zapach, odpowiedzialne są lotne związki organiczne. Źródłem pochodzenia lotnych związków organicznych, jest wydzielina gruczołów ekrynowych, apokrynowych i łojowych. Metabolizm związków wydzielanych przez w/w gruczoły, poprzez florę bakteryjną obecną na skórze oraz zachodzące reakcje utleniania, skutkują powstawaniem charakterystycznego dla każdego człowieka zapachu. Gruczoły potowe i łojowe są rozmieszczone nierównomiernie na powierzchni skóry, dlatego różne obszary ludzkiego ciała, wykazują odmienny „profil zapachowy”. Badania chromatograficzne wykazały, że na zapach człowieka składają się głównie niskocząsteczkowe kwasy tłuszczowe, aldehydy, ketony oraz związki zawierające azot i siarkę. Szczególną uwagę naukowców zwraca 2-nonenal, aldehyd, identyfikowany u osób powyżej 40 roku życia i uważany za potencjalny biomarker związany z wiekiem. Doniesienia literaturowe potwierdzają, że chromatografia gazowa wraz z nowoczesnymi technikami zatężania, może posłużyć do opracowania profilu zapachowego człowieka
Wybrane zasady Schiffa - badanie struktury i dynamiki
No full textProperties of liquid crystalline phases of the selected Schiff bases, i.e., nBBAA and nCBAA homologous series and 5BABB, 6BABB, 5BACB and 6BACB compounds, built of two benzene rings connected by the azomethine group, and of alkyloxy chain and halogene atom (B or Cl), are described in the PhD Thesis. In most of the substances the well-ordered smectic B (SmB) phase and the liquid-like smectic A (SmA) phase were observed. In case of the 5BBAA and 6BABB the smectic E (SmE) phase was also found. Influence of the Iso-SmA, Iso-SmB, SmA-SmB and SmB-SmE phase transitions on structural properties and dynamics were studied using various complementary experimental methods. In the first chapter the classification of liquid crystalline mesophases is presented. In the second chapter the results of polarized microscopy observation are discussed. Third chapter describes the results of X-ray diffraction studies. Fourth part presents in detail the rotational dynamics of selected compounds. The last chapter is focused on the results of the infrared spectroscopy (FT-IR) and the two dimensional correlation analysis of the FT-IR spectra. The most important results of the complementary studies are collected in the Summary. In Annex 1 the code (written in java) for the estimation of the unit cell parameters of SmB and SmE phases is presented. In Annex 2 the code (written for the SciLAB console), preparing the two dimensional correlation analysis is shown.Program Operacyjny Kapitał Ludzki POKL.04.01.01-00-434/08-02 współfinansowany ze środków Unii Europejskiej9
Eksploatacja Cyklotronu AIC-144 przystosowanego do celów medycznych cz. 2
No full textCyclotron AIC-144 is located in Krakow at the Institute of Nuclear Physics. It is currently used in proton radiotherapy ocular melanoma. This report presents the current state of the cyclotron and presents the work that was done in 2014. The report describes the distillate flow control module in the primary cooling circuit cyclotron AIC-144, cooling system, temperature measurement system and quality management system. The report pays particular attention to the issue of innovation, complexity and precision of action components. To ensure a steady state operation of the cyclotron systems ensure the stability of the temperature of the distillate. In order to avoid deviations from the established requirements Cyclotron Department has created a quality management system
Structure of Bi isotopes close to the 208Pb doubly-magic core
No full textThe atomic nucleus, being a dense system of protons and neutrons, can be considered as a 'laboratory' in which three fundamental interactions strong, electromagnetic and weak, can be studied. Although much experimental data concerning the structure and characteristics of the atomic nucleus have been collected, a theoretical description which would explain all the observed phenomena is still incomplete. This is in part because the nucleon-nucleon interaction has very complex characteristics due to the fact that nucleons are not fundamental particles so they have an intrinsic structure (thus, the description of nuclear forces must take into account that nucleon-nucleon interactions are the result of interactions between the quarks). It is also because the nucleus, as a system of many strongly interacting nucleons obeying the Pauli exclusion principle, demonstrates a very high degree of complexity. Moreover,
electromagnetic and weak interactions manifesting in the atomic nucleus are the source of additional complications in its description. As a consequence, progress in theory must go together with experimental investigations, which results in a strong connection between theory and experiment in nuclear physics. New theoretical concepts dictate which experiments would be the most effective in verifcation of a particular model. On the other hand, measurements can inspire theory to gain better parameter values from its models.
To describe the atomic nucleus as a system of more elementary constituents (nucleons), one needs to know the wave function being the solution of wave equation for such a system. Due to the diffculties mentioned above, one needs to use simplifed models instead of the exact description. One of them is the shell model, which explains many experimental observations, such as magic numbers of nucleons: 2, 8, 20, 28, 50, 82, 126, the spin-parity values of the
ground states of many nuclei, as well as the structure of excitations of nuclei in the region of magic nuclides. While the shell model with a classic set of orbitals works well near doublymagic nuclei lying close to the stability valley, in the exotic regions of the nuclear chart;
i.e., in the regions remote from stability, the situation is different - the structure of singleparticle energy levels changes and new energy gaps may show up while the classical ones may disappear.One way to trace all these changes, is to undertake systematic investigations of excited structures along a chain of neutron-rich isotopes to the description of which the shell model can be applied. In the present work, we have chosen as the objective of study the series of Bi isotopes near the doubly-closed nucleus 208Pb. We have investigated the 205;206;210Bi nuclei, which have one valence proton and from four neutron holes to one neutron particle with respect to the doubly-magic core 208Pb. Since 208Pb is considered to be one of the best doubly-closed cores due to remarkably wide energy gaps which separate proton shells at Z=82 and neutron shells at N=126, the structure of the 205;206;210Bi nuclei is an excellent testing
ground for modern shell-model calculations. In the present work, information about the high-spin yrast structures in the 205;206;210Bi isotopes has been extended. In particular, the aim of the work is the identifcation of high spin states arising from valence particles/holes
excitations and from core excitations in 205;206;210Bi. Also, the spectroscopic data on the low-spin excitations in 210Bi were acquired in a neutron-capture reaction. The neutron rich nuclei are diffcult to reach for spectroscopy studies, because they cannot be produced in fusion-evaporation reactions. The access to excited structures at high spin in those nuclides is possible thanks to a method which relies on using deep-inelastic collisions (DIC) of heavy ions - this method has been developed at IFJ PAN. The main object of interest in the presented thesis are high-spin structures in Bi isotopes. The experiments aimed at investigating those structures were performed at Argonne National Laboratory, where Bi nuclei were populated in deep-inelastic reactions with the use of 76Ge and 208Pb
beams on 208Pb target. During such reactions, the nuclei come to a close contact and much kinetic energy is dissipated giving rise to internal excitation energy. In the exit channel one has then two products excited to relatively high energy and spin. Since thick targets were used, the products were stopped inside the target and most of the rays that were measured with the use of the Gammasphere multidetector germanium array, appeared in the spectra as sharp lines - they were emitted from nuclei at rest. The second experiment, performed at the Institute Laue-Langevin in Grenoble, was devoted to the low-spin structure of the 210Bi nucleus. In this case 210Bi was produced in cold-neutron capture on 209Bi. The spectroscopic measurements in the non-yrast low-energy region of 210Bi could be performed. In the first chapter, an introduction to the structure of the atomic nucleus is presented - it includes: the characteristics of nuclear forces and the foundations of the shell model as well as the calculation methods and computer codes used nowadays. The second chapter provides a short description of the region of interest - the region around doubly-magic 208Pb - with emphasis on Bi isotopes. The third chapter presents description of the reactions leading to the nuclei of interest, the experiments which were performed, and the methods of analysis of the coincidence and angular distributions and correlations of -ray data. In the fourth chapter, the experimental results are discussed. The fifth chapter is devoted to comparisons of the experimental results with predictions based on shell-model calculations involving the presently available two-body shell-model interactions. The last part contains a summary.11
Assumptions for the design of a neutron pinhole camera dedicated to the PF-24 device
No full textThe report presents main assumptions on the design of the neutron pinhole camera dedicated to the PF-24 (Plasma Focus) device. The pinhole camera will be used for the investigation of the spatial and temporal distributions of DD neutrons from the PF-24 source. It makes use of principles of the optical geometry adopted for neutron imaging. In the report the evaluation of pinhole geometrical layout has been made on the basis of principles of the geometrical optics. A further optimization of the pinhole geometry has been carried out by means of neutron transport calculations (the MCNP code). The main aim of this report is to provide information on technical solutions for the neutron pinhole.The work has been performed within the framework of the strategic research project “Technologies supporting the development of safe nuclear power engineering” financed by the National Centre for Research and Development (NCBiR). Research task „Research and development of techniques for the controlled thermonuclear fusion”, Contract No. SP/J/2/143234/11
Beryllium neutron activation counter for pulsed D-D fusion sources
No full textThe fusion reaction occurring in DD plasma is followed by emission of 2.45 MeV neutrons, which carry out information about fusion reaction rate and plasma parameters and properties as well. Neutron activation of beryllium has been chosen for detection of DD fusion neutrons. The cross-section for reaction 9Be (n, α) 6He has a useful threshold near 1 MeV, which means that undesirable multiply-scattered neutrons do not undergo that reaction and therefore are not recorded. The product of the reaction, 6He, decays with half-life T1/2 = 0.807 s emitting β– particles which are easy to measure. Large area gas sealed proportional detector has been chosen as a counter of β– particles which leave activated beryllium plate. The plate with optimized dimensions adjoins the proportional counter entrance window. Such set-up is also equipped with appropriate electronic components and forms beryllium neutron activation counter.
The density of neutron flux on beryllium plate can be determined from the number of counts. Therefore, a proper calibration procedure needs to be performed to establish such a relation. The measurements with the use of known β– source have been done. In order to determine the detector response function such experiment has been modelled by means of MCNP5 – the Monte Carlo transport code. It has allowed a proper application of results of the transport calculations of β– particles emitted from the radioactive 6He and reaching the proportional detector active volume.
In order to test the counter system and measuring procedure a number of experiments have been performed on PF-6, PF-1000 and PF-4 devices. The experimental conditions have been simulated by means of MCNP5. The correctness of simulation outcome have been proved by measurements with known radioactive neutron source. The results of the DD fusion neutrons measurements have been compared with other neutron diagnostics.The work has been performed within the framework of the strategic research project “Technologies supporting development of safe nuclear power engineering” financed by the National Centre for Research and Development (NCBiR). Research task „Research and development of techniques for the controlled thermonuclear fusion”, Contract No. SP/J/2/143234/11.
The work was supported by EURATOM-EFDA under WP10-DIA-04-01 and WP11-DIA-03-01 agreements
Contribution to the T2K experiment at J-PARC, Tokai Design, assembly and installation of the SMRD modules (2008-2009)
No full textThe SMRD detectors (counters) of the T2K experiment are assembled into bigger units called modules. The final design of the modules was elaborated in the Division of Scientific Equipment and Infrastructure Construction (DAI) of the H.Niewodniczański Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN) in Krakow, Poland. The methods of the module assembly and stabilization inside the T2K magnet were also worked out. Installation procedures of the modules including cable handling were proposed as well. All elements and tools for the assembly, stabilization and installation of 440 SMRD modules had been produced in Poland in 2008. The SMRD modules had been assembled at J-PARC in Tokai and then installed in the T2K experiment in 2009
Detection of delayed neutrons from neutron activation of fissionable substance samples. Monte Carlo modelling of response of the DET-12 device
No full textActivation of fissionable elements by neutrons has been considered as a possible diagnostics of D-D and D-T fusion plasma. Fission caused by fusion neutrons leads up to emission of secondary neutrons: prompt and delayed. Proper interpretation of the time decay of delayed neutrons enables an assessment of the parameters of the primary neutron flux inducing fission. Monte Carlo calculations have been carried out by means of the MCNP code in order to elaborate the method considered. Three nuclides: pure 235U, 238U and 232Th, and additionally sintered UO2 have been selected as possible materials for the sample to be irradiated. Four energies of neutrons irradiating samples have been chosen: thermal, fast and two high ones. Computations have been accomplished for two variants: pure physical effect and real experimental conditions of neutron registration in the DET-12 device designed and built in IFJ PAN. Decay curves have been obtained for each case. Detection efficiency of DET-12 has been also estimated.The work has been performed within the framework of the strategic research project “Technologies supporting development of safe nuclear power engineering” financed by the National Centre for Research and Development (NCBiR). Research task „Research and development of techniques for the controlled thermonuclear fusion”, Contract No. SP/J/2/143234/11
