Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "R.I." wg kryterium: Autor


Tytuł:
Solution of diffusion-advection equation of radon transport in many-layered geological media
Autorzy:
Yakovleva, V. S.
Parovik, R. I.
Powiązania:
https://bibliotekanauki.pl/articles/148852.pdf
Data publikacji:
2010
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
radon
diffusion
advection
transport
modeling
soil
Opis:
Radon transport modeling in geological media is an important tool for solving problems and tasks of radioecology and geophysics. Comparison of radon field time series obtained by numerical and experimental methods is one of the most common and widely applicable ways to analyze the influence of state and variability of meteorological, electrical and actinometric parameters of atmosphere, cosmic weather factors, variations of deflected mode of geological medium on the level and variations of radon field. The solutions of stationary and non-stationary diffusion-advection equations of radon transport in many-layered geological media by numerical methods, notably by integro-interpolation method (balance method) are presented. The peculiarity of radon transport in many-layered media is taken into account in the developed numerical model. This peculiarity is connected with the transport equation coefficients which can change very rapidly at the border of two adjacent layers, i.e. they can be discontinuous at the borders of each layer that can be caused by parameters of soils greatly differing in value (density, porosity, radium content, diffusion and emanation coefficients). The present work is provided with an example of application of the developed numerical model for solving a practical problem on assessment of influence of deep seated uranium-containing rock on the value of radon volumetric activity at the depth of less-than or equal to 1 m. The article considers non-stationary numerical model calculations showing at what time moments the distribution curves of radon volumetric activity coincide with stationary regime of radon transport in geological media. The validity of the developed numerical solution has been confirmed by these calculations.
Źródło:
Nukleonika; 2010, 55, 4; 601-606
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Radionuclides in ground-level air and deposits near the Ignalina NPP
Autorzy:
Jasiulionis, R.
Savickaite, I.
Powiązania:
https://bibliotekanauki.pl/articles/148108.pdf
Data publikacji:
2001
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
atmosphere
environment of Ignalina NPP
numerical models
radionuclide
water-insoluble fractions
water-soluble fractions
Opis:
Abstract Results of systematic measurements of radionuclide activity concentrations in the air and deposits from January 1997 to July 2000 near the Ignalina Nuclear Power Plant (hereafter detoted as NPP) are presented. The data on NPP produced radionuclides 60Co and 54Mn in deposits and results of calculation are used for establishment of their distribution near NPP. Water-soluble and water-insoluble radionuclide fractions in the airborne effluents of NPP were investigated. The possibility to evaluate the deposition factor of water-soluble and water-insoluble radionuclides from the NPP jet by comparing the experimental data in the NPP stack and the environment is shown.
Źródło:
Nukleonika; 2001, 46, 4; 183-187
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
COREDIV modelling of JET ILW discharges with different impurity seeding: nitrogen, neon, argon and krypton
Autorzy:
Ivanova-Stanik, I.
Zagórski, R.
Powiązania:
https://bibliotekanauki.pl/articles/148412.pdf
Data publikacji:
2017
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
impurity seeding
integrated modelling
tokamak
Opis:
Numerical simulations with the COREDIV code of JET H-mode discharges with 25 MW of auxiliary heating in the ITER-like wall (ILW) configuration with different impurity seedings – nitrogen (N), neon (Ne), argon (Ar) and krypton (Kr) – are presented. All simulations have been performed with the same transport model and input discharge parameters like auxiliary heating, volume average plasma density, confi nement factor. Only the seeded impurity puff rate was changed in the calculations. It appears that for the considered heating power of 25 MW and relatively low volume electron average density = 6.2 × 1019 m–3, impurity seeding is necessary. It has been found that for every gas at the maximum level of the seeding rate, allowed by the code convergence, the power to the plate is reduced up to 2–4 MW, with electron temperature at the plate of about 2 eV, indicating semi-detached conditions in the divertor region. It should be noted, however, that in cases with low and medium Z impurity (N, Ne and Ar), tungsten radiation is a signifi cant part of radiation losses and stays above 22–32% of the total energy losses, but for high Z impurity (Kr) it is reduced up to 10% of the total losses. The maximum of the Kr radiation is between the pedestal region and separatrix, showing that radiative mantle can be created, which might have a strong influence on the plasma parameters in the pedestal region.
Źródło:
Nukleonika; 2017, 62, 1; 3-7
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:
The role and position of iron in 0.8CaZrO3-0.2CaFe2O4
Autorzy:
Szczerba, J.
Śnieżek, E.
Stoch, P.
Prorok, R.
Jastrzębska, I.
Powiązania:
https://bibliotekanauki.pl/articles/146129.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
calcium ferrite
calcium zirconate
Mössbauer spectroscopy
perovskite
spinel
Opis:
The aim of the study was to characterize the 0.8CaZrO3-0.2CaFe2O4 composite structure with particular emphasis on the role and position of iron in the function of sintering temperature. The paper presents the results of 57Fe Mössbauer effect at room temperature. It was found that the increase of sintering temperature causes an increase in the amount of incorporated iron ions in the CaZrO3-crystal structure. Based on Mössbauer spectroscopy analysis, it was found that three different environments of Fe3+ ions were observed in the obtained materials. Two of them corresponded to CaFe2O4 phase and one was associated with the substitution of Zr4+ by Fe3+ in the CaZrO3 structure.
Źródło:
Nukleonika; 2015, 60, 1; 147-150
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Position of Fe ions in MgO crystalline structure
Autorzy:
Szczerba, J.
Prorok, R.
Stoch, P.
Śnieżek, E.
Jastrzębska, I.
Powiązania:
https://bibliotekanauki.pl/articles/146372.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
Mössbauer spectroscopy
MgO
Fe ions
crystal structure
Opis:
Magnesium oxide (MgO) is one of the most important raw materials in many branches of industry. Magnesium oxide is a popular refractory raw material because of its high refractoriness and high resistance to basic slags and environment. In many cases, use of MgO is limited by its properties, especially the presence of secondary phases like iron oxides. The amount and distribution of iron oxides can strongly infl uence the technological properties of MgO and depend on the manufacturing method, particularly the heat-treatment process. The aim of the study was to evaluate the infl uence of the heat-treatment process on amount and distribution of iron ions in a magnesium oxide lattice. The 57Fe Mössbauer effect measurements of fused and sintered magnesium oxide samples doped by the iron oxide were conducted. Investigation reveals in both cases the presence of Fe2+ as well as Fe3+ ions. Fe2+ ions occupy Mg2+ octahedral sites in the MgO lattice, whereas the Fe3+ ions are located in highly distorted octahedral coordination. The amount of Fe2+ varies from around 66% for fused samples to 30% for sintered samples.
Źródło:
Nukleonika; 2015, 60, 1; 143-145
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of humic acids on EYL liposome membranes : ESR method
Autorzy:
Pytel, B.
Filipiak, A.
Pisarek, I.
Olchawa, R.
Man, D.
Powiązania:
https://bibliotekanauki.pl/articles/146924.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
EYL liposomes
ESR method
humic substances
Opis:
In this paper, the effects of model (commercial) and natural (extracted from peat) humic substances on the membrane of liposomes formed with egg yolk lecithin (EYL) are presented. In our research, mass concentrations of fulvic and humic acids were used, which in relation to lecithin varied from 0% to 13%. To study membrane fluidity, electron spin resonance (EPR) was used with two spin probes, penetrating various regions of the lipid bilayer. The effects of model and natural humic substances (humic acids – HAs and fulvic acids – FAs) on the lipid membrane in different regions were researched: the lipid-water interphase, and in the middle of the lipid bilayer. It was shown that FA and HA impact the fluidity of liposome membranes in different ways. Increased mass concentrations of HAs decreased membrane fluidity in both acids: extracted from peat and the model. However, increased mass concentration of FAs extracted from peat, decreased membrane fluidity in the surface region, at the same time stiffening the central part of the bilayer. Increasing the concentration of FAs extracted from peat had the opposite effect when compared to model FA. This effect may be related to the complexation of xenobiotics present in the soil environment and their impact on biological membranes.
Źródło:
Nukleonika; 2015, 60, No. 3, part 1; 455-459
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two new separation schemes for the group isolation of rare earth elements (REE) from biological and other matrices and their determination by ICP-MS, NAA and chromatographic methods
Autorzy:
Dybczyński, R. S.
Samczyński, Z.
Bartosiewicz, I.
Kulisa, K.
Polkowska-Motrenko, H.
Pyszynska, M.
Zuba, I.
Powiązania:
https://bibliotekanauki.pl/articles/147581.pdf
Data publikacji:
2017
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
rare earth elements
REE
lanthanides
ion exchange chromatography
NAA
ICP-MS
accuracy
certified reference materials
CRM
Opis:
Two new group separation schemes, based on ion exchange chromatography, for the selective and quantitative isolation of rare earth elements (REE) from accompanying elements, were devised. After checking their performance with the aid of radioactive tracers, the schemes were further used together with ICP-MS, NAA and ion exchange chromatography for the determination of Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in two certified reference materials (CRMs). The results were compared with another series of analyses, where the REEs were determined directly, i.e. without pre-separation, by instrumental neutron activation analysis (INAA) and inductively coupled plasma mass spectrometry (ICP-MS). It was demonstrated that while direct INAA and ICP-MS in most instances provide reliable results for the majority of REEs, for some elements, notably Sc, Yb and Tm in the cases of ICP-MS and INAA, respectively, systematic errors occur or may potentially occur.
Źródło:
Nukleonika; 2017, 62, 3; 199-211
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High pressures studies on hydrides of selected manganese alloys
Autorzy:
Sugiura, H.
Filipek, S.
Paul-Boncour, V.
Marchuk, I.
Liu, R.
Pyun, S.
Powiązania:
https://bibliotekanauki.pl/articles/146225.pdf
Data publikacji:
2006
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
deuterides/hydrides
high pressure
ferromagnetic fcc-manganese
Laves phases
equation of state
Opis:
Specific behavior found in hydrides formed in manganese, Mn-Ni and YMn2 under high pressure is presented and discussed. The synthesis of ferromagnetic fcc-manganese was proved. Parameters of the equations of state (EOS) derived from measurements in the diamond anvil cell (DAC) are summarized for manganese hydrides and for hydrides derived from YMn2 Laves phase. It was found that the compression behavior of recently discovered YMn2H6 is different from YMn2-based hydrides with lower hydrogen content.
Źródło:
Nukleonika; 2006, 51,suppl.1; 73-77
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of air conditioning changes on the effective dose due to radon and its short-lived decay products
Autorzy:
Grządziel, A.
Kozak, K.
Mazur, J.
Połednik, B.
Dudzińska, M. R.
Bilska, I.
Powiązania:
https://bibliotekanauki.pl/articles/147303.pdf
Data publikacji:
2016
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
radon
radon progeny
attached fraction of radon progeny
unattached fraction of radon progeny
dose conversion factor
Opis:
Most people spend the majority of their time in indoor environments where the level of harmful pollutants is often significantly higher than outdoors. Radon (222Rn) and its decay products are the example of radioactive pollutants. These radioisotopes are the main source of ionizing radiation in non-industrial buildings. The aim of the study was to determine the impact of air-conditioning system on radon and its progeny concentrations and thus on the effective dose. The measurements were carried out in the auditorium at the Environmental Engineering Faculty (Lublin University of Technology, Poland). Measurements of radon and its progeny (in attached and unattached fractions) as well as measurements of the following indoor air parameters were performed in two air-conditioning (AC) operation modes: AC ON and AC ON/OFF. The air supply rate and air recirculation were taken into consideration. The separation of radon progeny into attached and unattached fractions allowed for determining, respectively, the dose conversion factor (DCF) and the inhalation dose for teachers and students in the auditorium. A considerable increase of the mean radon progeny concentrations from 1.2 Bq/m3 to 5.0 Bq/m3 was observed in the AC ON/OFF mode compared to the AC ON mode. This also resulted in the increase of the inhalation dose from 0.005 mSv/y to 0.016 mSv/y (for 200 h/year). Furthermore, the change of the air recirculation rate from 0% to 80% resulted in a decrease of the mean radon concentration from 30 Bq/m3 to 12 Bq/m3 and the reduction of the mean radon progeny concentration from 1.4 Bq/m3 to 0.8 Bq/m3. This resulted in the reduction of the inhalation dose from 0.006 mSv/y to 0.003 mSv/y.
Źródło:
Nukleonika; 2016, 61, 3; 239-244
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Erratum to “Simulation of operation modes of isochronous cyclotron by a new interative method” [Nukleonika 2007;52(1):29-34]
Autorzy:
Taraszkiewicz, R.
Talach, M.
Sulikowski, J.
Doruch, H.
Norys, T.
Sroka, A.
Kiyan, I.
Powiązania:
https://bibliotekanauki.pl/articles/146579.pdf
Data publikacji:
2007
Wydawca:
Instytut Chemii i Techniki Jądrowej
Źródło:
Nukleonika; 2007, 52, 2; 83-83
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crystal structure and Mössbauer study of FeAl2O4
Autorzy:
Jastrzębska, I.
Szczerba, J.
Stoch, P.
Błachowski, A.
Ruebenbauer, K.
Prorok, R.
Śnieżek, E.
Powiązania:
https://bibliotekanauki.pl/articles/147676.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
FeAl2O4
hercynite
Mössbauer spectroscopy
spinel
Opis:
In this work the synthesis of hercynite from Fe2O3 and Al2O3 powders was carried out by arc-melting method under the protective argon atmosphere. The obtained material was characterized with the use of powder X-ray diffractometry (XRD) and Mössbauer spectroscopy (MS). A Mössbauer effect in hercynite obtained by the arc-melting method indicated the cations distribution in the spinel structure among the tetrahedral and octahedral interstices. The presence of Fe2+ ions was detected in both tetrahedral and octahedral sites while Fe3+ ions occupied only the octahedral interstices. The approximate formula of the obtained iron-aluminate spinel was as follows (Fe2+ 0.77Al3+0.23)(Fe3+0.07Fe2+0.05Al0.88)2O4.
Źródło:
Nukleonika; 2015, 60, 1; 47-49
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of operation modes of isochronous cyclotron by a new interative method
Autorzy:
Taraszkiewicz, R.
Talach, M.
Sulikowski, J.
Doruch, H.
Norys, T.
Sroka, A.
Kiyan, I.
Powiązania:
https://bibliotekanauki.pl/articles/148258.pdf
Data publikacji:
2007
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
cyclotron
operation mode
mathematical model
Opis:
Operation mode simulation methods are based on selection of trim coil currents in the isochronous cyclotron for formation of the required magnetic field at a certain level of the main coil current. The traditional current selection method is based on finding a solution for all trim coils simultaneously. After setting the calculated operation mode, it is usually necessary to perform a control measurement of the magnetic field map and to repeat the calculation for a more accurate solution. The new current selection method is based on successively finding solutions for each particular trim coil. The trim coils are taken one by one in reverse order from the edge to the center of the isochronous cyclotron. The new operation mode simulation method is based on the new current selection method. The new method, as against the traditional one, includes iterative calculation of the kinetic energy at the extraction radius. A series of experiments on proton beam formation within the range of working acceleration radii at extraction energies from 32 to 59 MeV, which were carried out at the AIC144 multipurpose isochronous cyclotron (designed mainly for the eye melanoma treatment and production of radioisotopes) at the INP PAS (Kraków), showed that the new method makes unnecessary any control measurements of magnetic fields for getting the desired operation mode, which indicates a high accuracy of the calculation.
Źródło:
Nukleonika; 2007, 52, 1; 29-34
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study on optimization of sample preparation for gas chromatographic methods used in routine irradiated foodstuffs detection
Autorzy:
Virgolici, M.
Medvedovici, A. V.
Manea, M. M.
Cutrubinis, M.
Moise, I. V.
Georgescu, R.
Powiązania:
https://bibliotekanauki.pl/articles/148092.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
irradiated foodstuffs detection
gas chromatography
Opis:
The study is focused on the optimization and minimization of sample preparation procedures given in EN 1784 and EN 1785 standardized methods for the detection of irradiated foodstuffs which contain fats. The techniques used in this study were gas chromatography (GC) with a flame ionization detector (FID) for hydrocarbons (HC) detection and GC coupled with mass spectrometry (MS) for 2-alkylcyclobutanones detection. Our work revealed that alternative extraction and clean-up procedures as well as alternative injection modes like large volume injection can significantly reduce the total analysis time and costs with comparable results.
Źródło:
Nukleonika; 2009, 54, 2; 115-121
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Incomplete energy deposition in long CsI(Tl) crystals
Autorzy:
Siwek, A.
Budzanowski, A.
Czech, B.
Fomichev, A.
Gburek, T.
Rodin, A.
Skwirczynska, I.
Wolski, R.
Powiązania:
https://bibliotekanauki.pl/articles/147049.pdf
Data publikacji:
2002
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
nuclear interaction in solids
scintillation detectors
Opis:
We studied process of incomplete energy deposition in long CsI(Tl) crystals, caused by inelastic interactions of impinging nuclear fragment in the scintillating material. The secondary beam from the ACCULINNA fragment separator and the heavy-ion beam from the CELSIUS storage ring were used to measure the yield of this process as a function of the initial energy of incoming fragments. The functional fit to GEANT simulations will be used to correct the energy spectra from future experiments.
Źródło:
Nukleonika; 2002, 47, 4; 141-145
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies