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[en] This session featured the advances several Member States have made in the area of developing a national nuclear forensics library to support a nuclear forensic interpretation. A national nuclear forensics library is one tool that may be used to potentially determine whether characteristics of materials found outside of regulatory control are consistent with nuclear material and other radioactive material used, produced or stored within a State
[en] Nitrogen and oxygen doped and co-doped GeSbTe (GST) films for phase-change optical recording are investigated. It is found that the crystallization temperature increased as well as the crystalline microstructure refined by doping. The carrier-to-noise ratio (CNR) and erasability of phase-change optical disks are improved being up to 52 and 35 dB, respectively, by using an appropriate nitrogen doping or co-doping concentration in the recording layer. Optical disks with co-doped recording layer are found to be superior in the recording characteristics then the single doped recording layer disks
[en] The integrated in the program environment Matlab module Simulink is used to create models for simulating the starting and working conditions of a wind-powered asynchronous generator. A model has been created to simulate the soft starter and the switch-controlled capacitor bank. The electrical characteristics for several working conditions has been examine truth simulation. (authors)
[en] The interest to the investments in a wind energetics increases in the last years. The wind energetics is the fastest developing direction in the energetics in global scale. The wind energy is more attractive because its prices are lower in comparison of the other technologies for generating energy. The right choice of the surge protective devices has the important meaning on building and exploitation of the wind generators. The aim of this paper is investigation of the surge protective devices operation when they are installation to a wind generator. (authors)
[en] A scheme for initial quantitative analysis of lead samples from proejctiles carried out by means of instrumental neutron activation analysis, was proposed. It gave an opportunity for determination of the concentrations of Sb, As, Cu and Ag when the contents of Sb were less than 0,005%. The analysis time did not exceed 20-25 min
[en] A quantitative measurement of the contents of 17 chemical elements in soil samples, collected using the existing network from the surface of five cultivated areas in Bulgaria has been carried out. The values obtained have been used to calculate the evaluations psub(i) of the dispersions and for the ordering of the chemical elements according to their importance in criminology. The possibility for criminological comparison of single soil samples using the contents of the five most important elements - Th, Fe, Sc, Ce and Mn has been shown. (author)
[en] Pancreatic cancer is a quick progression disease and unfavorable prognosis. It is the sixth cause for cancer related death worldwide. Focused ultrasound surgery (FUS) using High Intensity Ultrasound (HIFU) is a noninvasive procedure that can be used as a part of the complex treatment of advanced pancreatic cancer patients. The aim of this paper is to present literature data on the potentiality of FUS as an innovative instrument for local treatment for patients with advanced pancreatic cancer. A non-systematic literature review was performed using the databases of PubMed, Scopus, EMBASE and Cochrane Library to identify articles published before 1st of September about FUS using HIFU for treatment of patients with advanced pancreatic cancer. The researches include at least 20 patients and report data about the procedure, complications, local tumor control, pain and survival. The research results worldwide show FUS to be secure and safe in the treatment of patients with advanced pancreatic cancer. Large, prospective multicenter trials about this innovative treatment are needed.
[en] The aim of this study was to ascertain the degree and direction of those changes in physicochemical characteristics of irradiated peaches and grapes which determine their quality after irradiation and during storage. The following main conclusions are made: irradiation with doses of 200 to 300 krad does not cause significant alterations in the chemical composition and physicochemical characteristics of peaches and grapes; irradiation has a direct effect on the consistancy of peaches and grapes, leading to their softening which is proportional to the radiation dose used; radiation treatment is advisable in the case of peaches and grapes in tended for short-term rather than long-term storage at low temperatures
[en] The aim of the study was to determine the volume and concentration of the contrast media needed for examination. Lipid-soluble (Lipiodol ultrafluide) and water-soluble (Biligrafin, 75 % Urpolin and 76 % Uroprafin) preparations were used. Investigations were performed on skulls, in the sinuses of which paper globules were introduced, aimed at resembling altered sinus mucosa. The contrast media was insufflated in a rubber baloon, inserted in the sinus cavity. It was found that water-soluble preparations were most appropriate after fourfold dilution with physiologic saline. Lipid-soluble preparations proved not to be suitable for examining patients with chronic odontogenic sinusitis. The results of this study were confirmed by authors' clinical experience. 12 refs
[en] Diamond is a unique material for x-ray energy conversion. Its high thermal conductivity and low coefficient of thermal expansion make it ideal for high heat load environments. However, its large bandgap, while offering insensitivity to visible light, makes charge trapping more likely (thermal detrapping less likely) than in silicon; energy conversion efficiency is also 3-4 times less even under the best conditions. High material strength and x-ray transmission also are potentially useful features for certain applications in x-ray science. Limitations to charge collection efficiency such as recombination and charge trapping have been investigated quantitatively using quasi-continuous tunable synchrotron radiation under flexible biasing schemes as well using detailed Monte Carlo Simulations. In the case of charge collection efficiency, the magnitude of the applied field, initial particle energy, and probe depth are adjusted. The diffusion and drift of photo-generated charge clouds are explicitly considered for the specific energy loss behavior of diamond. While recombination loss at the entrance window of diamond diodes is qualitatively similar to a treatment for an additional 'dead' carbon window layer, the observed field and photon energy dependence implies that the more sophisticated model is more correct quantitatively. In addition, charge propagation in diamond is unique in that photoconductive gain is possible. Effectively, charge trapping of one carrier leads to screening of the applied field. In order to avoid photoconductive gain, either blocking contacts or explicit detrapping is required. Quantitative analysis of photoconductive gain as a function of applied field, x-ray power, waveform and photon energy offers insight into the fundamental limitations of state of the art single crystal diamond. Simple models are proposed to assist in extrapolating the observed behavior towards useful detector devices.