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Tytuł:
X pinch as a source for X-ray radiography
Autorzy:
Pikuz, S.
Shelkovenko, T.
Romanova, V.
Sinars, D.
Hammer, D.
Bland, S.
Lebedev, S.
Powiązania:
https://bibliotekanauki.pl/articles/147532.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
wire array
X-pinch
X-ray imaging
X-ray radiography
Z-pinch
Opis:
This article describes several applications and methods using the X pinch as a source of X-ray radiation for the radiography of dense plasma objects. These methods, in general, do not use pinholes, and instead take the advantage of the small size (<1 mm, and in some cases <3 mm) and a short X-ray emission duration (<1 ns) of the radiation source produced by an X pinch. Two of these methods, monochromatic and direct point-projection backlighting, are discussed. Experimental images of exploding wires and wire arrays obtained on the BIN, XP, and MAGPIE generators using these techniques are presented. Also included are detailed measurements made on the XP generator of the emission characteristics of X pinches using different wire materials.
Źródło:
Nukleonika; 2001, 46, 1; 21-25
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ultrafast X-ray introspective imaging of metallic objects using a Plasma Focus
Autorzy:
Moreno, C. H.
Clausse, A.
Martínez, J. F.
Llovera, R.
Tartaglione, A.
Powiązania:
https://bibliotekanauki.pl/articles/146595.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
dense plasmas
electrical discharges
plasma focus
X-ray imaging
X-rays
Opis:
A compact-chamber 4.7 kJ, 30 kV, Plasma Focus operated in deuterium was used as a ultrafast high intensity radiation source for introspective radiographic imaging of metallic objects. The samples to be imaged were located outside the Plasma Focus chamber, about 1 m away from the chamber wall. A high-sensitivity, fast-response commercial radiographic film was used as a X-ray detector. Experimentally obtained images are presented showing a very high penetration power of the X-ray beam, demonstrating that the presented compact-chamber Plasma Focus is suited for introspective visualisation of pieces manufactured on metal.
Źródło:
Nukleonika; 2001, 46, suppl. 1; 33-34
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectral resolution of Cauchois-Johansson spectrometer
Autorzy:
Baronova, E. O.
Stepanenko, M. M.
Powiązania:
https://bibliotekanauki.pl/articles/147963.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
resolution
spectrograph
X-rays
Opis:
Spectral resolution of a Cauchois-Johansson spectrometer is analyzed analytically and studied experimentally, using an X-ray tube. Widening of Mo K-alpha spectra, taken in the transmission regime are discussed. Spectral resolution is shown to be δλ/λ ≈ 1.7×10–3. This value is explained by the influence of crystal thickness and diffraction defocusing of line.
Źródło:
Nukleonika; 2001, 46, suppl. 1; 53-56
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recent measurements of soft X-ray emission from the DPF-1000U facility
Autorzy:
Surała, W.
Sadowski, M. J.
Paduch, M.
Zielinska, E.
Tomaszewski, K.
Powiązania:
https://bibliotekanauki.pl/articles/148171.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
plasma focus
X-ray emission
X-ray images
gas puffing
filaments
hot spots
Opis:
Soft X-ray imaging is a very useful diagnostic technique in plasma-focus (PF) experiments. This paper reports results of four experimental sessions which were carried out at the DPF-1000U plasma-focus facility in 2013 and 2014. Over 200 discharges were performed at various experimental conditions. Measurements were taken using two X-ray pinhole cameras with a line of sight perpendicular to the z-axis, at different azimuthal angles (about 20° and 200°), and looking towards the centre of the PF-pinch column. They were equipped with diaphragms 1000 μm or 200–300 μm in diameter and coated with filters of 500 μm Al foil and 10 μm Be foil, respectively. Data on the neutron emission were collected with silver activation counters. For time-resolved measurements the use was made of four PIN diodes equipped with various fi lters and oriented towards the centre of the PF-column, in the direction perpendicular to the electrode axis. The recorded X-ray images revealed that when the additional gas-puff system is activated during the discharge, the stability of the discharge is improved. The data collected in these experiments confi rmed the appearance of a filamentary fi ne structure in the PF discharges. In the past years the formation of such fi laments was observed in many Z-pinch type experiments. Some of the recorded X-ray images have also revealed the appearance of the so-called hot- -spots, i.e. small plasma regions of a very intense X-ray emission. Such a phenomenon was observed before in many PF experiments, e.g. in the MAJA-PF device, but it has not been investigated so far in a large facility such as the DPF-1000U. The time-resolved measurements provided the evidence of a time lapse between the X-ray emission from plasma regions located at different distance from the anode surface. The formation of distinct ‘hot-spots’ in different instants of the DPF-1000U discharge was also observed.
Źródło:
Nukleonika; 2015, 60, 2; 303-308
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-ray techniques in the investigation of a Gothic sculpture : the risen Christ
Autorzy:
Mikołajska, A.
Walczak, M.
Kaszowska, Z.
Urbańczyk-Zawadzka, M.
Powiązania:
https://bibliotekanauki.pl/articles/146866.pdf
Data publikacji:
2012
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
cultural heritage
X-ray image
X-ray dual source computed tomography (DSCT)
scanning electron microscopy energy dispersed X-ray spectroscopy (SEM-EDX)
Opis:
For over a century, X-ray radiation has played an important role in the area of the conservation and restoration of cultural heritage objects. X-ray techniques are amongst the most fundamental and helpful methods used in the investigation of art works. This paper reviews the application of traditional radiography, X-ray dual source computed tomography (DSCT) and scanning electron microscopy combined with energy dispersed X-ray spectroscopy (SEM-EDX) to the investigation of a wooden, Gothic sculpture, The risen Christ. Thanks to the properties of X-ray radiation (different absorption by various materials) first two methods allow the assessment of the preservation state and the observation of the internal structure of an object in 3-D. While SEM-EDX analysis permits the elemental analysis of the polychrome layers. As a result 2-D and 3-D images, permitting the full volume inspection of an object, were taken in a totally non-destructive way. The morphological and physical information about the inner structure of the investigated wooden sculpture was obtained, revealing changes related to previous restorations, as well as ageing effects. Employing the SEM-EDX, painting materials (pigments and filers), were identified. Gained data is essential for restorers to understand the whole structure of the studied object and to decide which further investigation and restoration steps have to be undertaken.
Źródło:
Nukleonika; 2012, 57, 4; 627-631
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preliminary study on X-ray source from Plasma Focus device for fast radiography
Autorzy:
Da Re, A.
Mezzetti, F.
Tartari, A.
Verri, G.
Rapezzi, L.
Gribkov, V. A.
Powiązania:
https://bibliotekanauki.pl/articles/147243.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
plasma focus
X-ray sources
Opis:
Plasma derived flash X-ray sources may find potential applications in medicine and industry. Notwithstanding, as is the case of Plasma Focus (PF) devices, their characterisation in term of photon energy, temporal and spatial beam stability is far to be considered satisfactory. In this work, a radiographic approach, which avoids the effects caused by the intrinsic instability of the pinch output of a PF machine, is proposed and an attenuation curve can be attained even in presence of Xray emission instability. Using two radiographic films for each shot exposition symmetrically positioned and collimated to the pinch region the mean energy of the photons in the X-ray beam are evaluated. The X-ray emission symmetry from the pinch region was then utilised to control the validity of the proposed methodology.
Źródło:
Nukleonika; 2001, 46, suppl. 1; 123-125
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dense Plasma Focus as a powerful source of monochromatic X-ray radiation
Autorzy:
Dubrovsky, A.
Gribkov, V.
Ivanov, Y.
Karpiński, L.
Orlova, M.
Powiązania:
https://bibliotekanauki.pl/articles/147444.pdf
Data publikacji:
2006
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
dense plasma focus (DPF)
X-ray generation
X-ray dosimetry
exposure dose
absorbed dose
Opis:
A review of some experimental results obtained using the dense plasma focus (DPF) device PF-1000 is presented. The copper Ka1,2 radiation line generated by DPF in the case of device anode made of copper was the main object of this study. The predominance of this characteristic radiation over other kinds of radiation in the DPF X-ray spectrum is shown. A brief description of a new DPF 6.0 device as well as a radioenzymology experiment carried out within this device is presented.
Źródło:
Nukleonika; 2006, 51, 1; 21-28
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of the soft X-ray tungsten spectra expected to be registered by GEM detection system for WEST
Autorzy:
Syrocki, Ł.
Szymańska, E.
Słabkowska, K.
Polasik, M.
Pestka, G.
Powiązania:
https://bibliotekanauki.pl/articles/971490.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
X-ray spectra
tokamak
tungsten L, M, N, X-ray lines
GEM detection system
Opis:
In the future International Thermonuclear Experimental Reactor (ITER), the interaction between the plasma and the tungsten chosen as the plasma-facing wall material imposes that the hot central plasma loses energy by X-ray emission from tungsten ions. On the other hand, the registered X-ray spectra provide alternative diagnostics of the plasma itself. Highly ionized tungsten emits extremely complex X-ray spectra that can be understood only after exhaustive theoretical studies. The detailed analyses will be useful for proper interpretation of soft X-ray plasma radiation expected to be registered on ITER-like machines, that is, Tungsten (W) Environment in Steady-state Tokamak (WEST). The simulations of the soft X-ray spectra structures for tungsten ions have been performed using the flexible atomic code (FAC) package within the framework of collisional-radiative (CR) model approach for electron temperatures and densities relevant to WEST tokamak.
Źródło:
Nukleonika; 2016, 61, 4; 433-436
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
X-ray tube with needle-like anode
Autorzy:
Słapa, M.
Straś, W.
Traczyk, M.
Dora, J.
Snopek, M.
Gutowski, R.
Drabik, W.
Powiązania:
https://bibliotekanauki.pl/articles/147038.pdf
Data publikacji:
2002
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
brachytherapy
photon needle
X-ray tube
Opis:
An X-ray tube with a needle-like anode (NAXT) built in our Laboratory, its design and basic operating parameters are presented. The process of electron beam forming and influence of external and internal magnetic fields is discussed. The tube properties essential from the point of view of its application in X-ray generators as well as disadvantageous thermal effects caused by flow of heat generated in the tube target to irradiated objects are discussed. The tube is almost a point-like source of X radiation emitted into 4đ geometry; the dose rates are on the order of 1 Gy/min at the distance of 10 mm from the anode cap. Preliminary tests show the tube may be useful in brachytherapy of cancer tumors of diameter up to 30 mm. The tube may also be an interesting device in widely understood field of irradiation techniques.
Źródło:
Nukleonika; 2002, 47, 3; 101-105
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multichannel calorimeters for measurement of flows of X-ray radiation in the range from 10 up to 200 keV
Autorzy:
Vinogradov, V. P.
Powiązania:
https://bibliotekanauki.pl/articles/148228.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
calorimeter
hard X-ray
plasma focus
Opis:
An 8-channel calorimeter was developed and applied to the Plasma focus facility (PF) with flat geometry of electrodes (Filippov type) for the measurements of a hard X-ray (HXR) radiation yield and its spectral distribution. The calorimeter measures the time-integrated HXR flux for one shot of the PF facility without any additional calibrations. The sensitivity ~10–4 J/cm2 was achieved.
Źródło:
Nukleonika; 2001, 46, suppl. 1; 99-101
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Clastogenic effects in human lymphocytes exposed to low and high dose rate X-ray irradiation and vitamin C
Autorzy:
Konopacka, M.
Rogoliński, J.
Powiązania:
https://bibliotekanauki.pl/articles/147589.pdf
Data publikacji:
2011
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
vitamin C
X-radiation
dose rate
Opis:
In the present work we investigated the ability of vitamin C to modulate clastogenic effects induced in cultured human lymphocytes by X-irradiation delivered at either high (1 Gy/min) or low dose rate (0.24 Gy/min). Biological effects of the irradiation were estimated by cytokinesis-block micronucleus assay including the analysis of the frequency of micronuclei (MN) and apoptotic cells as well as calculation of nuclear division index (NDI). The numbers of micronucleated binucleate lymphocytes (MNCBL) were 24.85 š 2.67% and 32.56 š 3.17% in cultures exposed to X-rays (2 Gy) delivered at low and high dose rates, respectively. Addition of vitamin C (1-20 mi g/ml) to the medium of cultures irradiated with the low dose rate reduced the frequency of micronucleated lymphocytes with multiple MN in a concentration-dependent manner. Lymphocytes exposed to the high dose rate radiation showed a U-shape response: low concentration of vitamin C significantly reduced the number of MN, whereas high concentration influenced the radiation-induced total number of micronucleated cells insignificantly, although it increased the number of cells with multiple MN. Addition of vitamin C significantly reduced the fraction of apoptotic cells, irrespective of the X-ray dose rate. These results indicate that radiation dose rate is an important exposure factor, not only in terms of biological cell response to irradiation, but also with respect to the modulating effects of antioxidants.
Źródło:
Nukleonika; 2011, 56, 4; 253-257
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
57Fe Mössbauer spectroscopy and X-ray diffraction study of gadolinites REE2Fe2+Be2Si2O10 from Lower Silesia (Poland) and Ytterby (Sweden)
Autorzy:
Malczewski, D.
Powiązania:
https://bibliotekanauki.pl/articles/148858.pdf
Data publikacji:
2003
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gadolinite
Mössbauer spectroscopy
X-ray diffraction
Opis:
This paper reports the results of 57Fe Mössbauer spectroscopy, X-ray diffraction (XRD) and gamma-ray spectroscopy studies of partially metamict gadolinites from Szklarska Poręba and Zimnik (Lower Silesia, Poland), a fully metamict gadolinite sample from Ytterby (Sweden) and a crystalline sample obtained after annealing of a fragment of the sample from Ytterby at 1373 K in an argon atmosphere. Both fully metamict and crystalline gadolinite show divalent iron exclusively in octahedral coordination. Changes of the amplitudes ratio of high energy to low energy absorption peaks from Fe2+ quadrupole doublets are strictly correlated with calculated absorbed alpha-dose and the metamictization stages of the gadolinite specimens. In this respect, one of the samples is in conflict with the estimated radiation dose based on age and radionuclide concentrations. In this case, Mössbauer spectroscopy shows that the sample had to be naturally annealed over geologic time.
Źródło:
Nukleonika; 2003, 48,suppl.1; 41-44
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Conceptual design of Light Impurity Monitor for Wendelstein 7-X
Autorzy:
Książek, I.
Burhenn, R.
Musielok, J.
Powiązania:
https://bibliotekanauki.pl/articles/146640.pdf
Data publikacji:
2011
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
plasma spectroscopy
stellarator
soft X-ray
Opis:
As plasma impurity ions can significantly influence the properties of a fusion plasma by dilution and enhancement of the radiation losses, the process of monitoring of their concentrations is one of the most important tasks. A Light Impurity Monitor is needed for monitoring the contamination of the stellarator plasma by carbon, nitrogen, boron, and oxygen impurities, which are indicators for the overload of the plasma facing components, leakage of the vacuum vessel, or wall condition, respectively. Their concentration will be estimated on the basis of emission intensities of their hydrogen-like ions. In this paper a conceptual design of such a spectrometer is presented, including the description of the geometry, the acquisition system and safety systems.
Źródło:
Nukleonika; 2011, 56, 2; 155-160
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Second order reflection from crystals used in soft X-ray spectroscopy
Autorzy:
Książek, I.
Powiązania:
https://bibliotekanauki.pl/articles/146093.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
soft X-ray
plasma spectroscopy
PbSt
KAP
Opis:
In this note the ratio of the second to the first order reflection is determined for the KAP and PbSt crystals, for wavelengths corresponding to the Al K-line emission. The source of the radiation was a low-voltage stabilized X-ray tube. The X-rays were detected with a Bragg spectrometer equipped with a proportional counter detector. The signal measured by the proportional counter was subsequently pulse height analyzed.
Źródło:
Nukleonika; 2015, 60, 2; 263-265
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of soft X-ray tomography on the COMPASS tokamak
Autorzy:
Imríšek, M.
Mlynář, J.
Löffelmann, V.
Weinzettl, V.
Odstrčil, T.
Odstrčil, M.
Tomeš, M.
Powiązania:
https://bibliotekanauki.pl/articles/146251.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
soft X-ray
tomography
Tikhonov regularization
tokamak
Opis:
The COMPASS tokamak is equipped with the soft X-ray (SXR) diagnostic system based on silicon photodiode arrays shielded by a thin beryllium foil. The diagnostic is composed of two pinhole cameras having 35 channels each and one vertical pinhole camera with 20 channels, which was installed recently to improve tomographic inversions. Lines of sight of the SXR detectors cover almost complete poloidal cross section of the COMPASS vessel with a spatial resolution of 1–2 cm and temporal resolution of about 3 s. Local emissivity is reconstructed via Tikhonov regularization constrained by minimum Fisher information that provides reliable and robust solution despite limited number of projections and ill-conditionality of this task. Improved border conditions and numerical differentiation matrices suppressing artifacts in reconstructed radiation were implemented in the code. Furthermore, a fast algorithm eliminating iterative processes was developed, and it is foreseen to be tested in real-time plasma control.
Źródło:
Nukleonika; 2016, 61, 4; 403-408
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł

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