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EN
In this paper the analysis of electric systems' structures in nuclear power plants with emphasis on ensuring the operational reliability has been prepared. The authors focused on different issues regarding necessary conditions of a safe work of nuclear power plant. Based on authors research the auxiliaries’ power supply systems must be designed to assure a maximal reliability level of the supply for the most important auxiliaries. In the nuclear power plant, it is necessary to remove the decay heat produced in nuclear fuel during the long time after the reactor shutdown. It is also necessary to supply the devices responsible for the radiation protection of people and environment. The authors analyzed the categories of the nuclear power plant auxiliaries and the standards for qualifying electrical equipment for nuclear power plants. Electric part of nuclear power plant is a set of electric power equipment, interconnected using the electric current paths, designed to leading-out energy from the power plant to the electric power system (power leading-out system) and to supply auxiliaries (auxiliaries’ power supply system). The tasks of auxiliaries’ power supply system in normal conditions differ significantly from the tasks that this system satisfies in the transient conditions: starts-up, shut-downs and failures. The other thing is presented review of solutions of auxiliaries’ power supply in currently developed plants. The paper presents the solutions of auxiliaries’ power supply system in chosen power plants, which are presently design and/or in construction process.
PL
W artykule dokonano analizy struktur układów elektrycznych w elektrowniach jądrowych, ze szczególnym uwzględnieniem zapewnienia niezawodności operacyjnej. Autorzy skupili się na różnych zagadnieniach dotyczących niezbędnych warunków bezpiecznej pracy elektrowni jądrowej. Układy zasilania potrzeb własnych muszą być projektowane tak, aby zapewnić maksymalny poziom niezawodności zasilania najważniejszych odbiorników potrzeb własnych. W elektrowni jądrowej konieczne jest usuwanie ciepła wytwarzanego w paliwie jądrowym przez długi czas po wyłączeniu reaktora. Konieczne jest również zasilanie urządzeń odpowiedzialnych za ochronę radiologiczną ludzi i środowiska. Autorzy przeanalizowali kategorie urządzeń potrzeb własnych elektrowni jądrowej oraz standardy kwalifikowania urządzeń elektrycznych dla elektrowni jądrowych. Część elektryczna elektrowni jądrowej to zespół urządzeń elektroenergetycznych, połączonych torami prądowymi, przeznaczony do wyprowadzenia energii z elektrowni do systemu elektroenergetycznego (układ wyprowadzenia mocy) oraz do zasilania potrzeb własnych (układ zasilania potrzeb własnych). Zadania układu zasilania potrzeb własnych w normalnych warunkach znacznie odbiegają od zadań, które spełnia ten układ w warunkach przejściowych: rozruchy, wyłączenia i awarie. Kolejnym elementem artykułu jest przegląd rozwiązań zasilania potrzeb własnych w obecnie budowanych elektrowniach jądrowych. W artykule przedstawiono rozwiązania układów zasilania potrzeb własnych w wybranych elektrowniach, które są obecnie projektowane i / lub budowane.
EN
The purpose of this paper is to demonstrate the possibilities of the EcoTech System’s solution to support the implementation of the assumptions of the Extended Producer Responsibility. The research methods used to accomplish this goal are literature studies and case study – “MSGO – EcoTech System”. EU standards impose a high level of recovery and recycling on the Member States. It is clear that, in order to fulfil the sense of social justice, those who directly contributed to this situation, i.e. consumers and producers, should also participate in this process. However, manufacturers need tools to monitor the efficiency and effectiveness of their operations. The presented “MSGO – EcoTech System” is based on the incentives scheme. The basis is the assumption that companies which declare CSR in their business strategy will join and will participate in the creation of new incentives for citizens. The example confirms that there are modern solutions which can support companies in the implementation of EPR. The obtained results provide guidelines for companies seeking solutions in this area.
PL
Celem artykułu jest zademonstrowanie możliwości rozwiązania EcoTech System wspierającego wdrożenie założeń rozszerzonej odpowiedzialności producenta. Metodami badawczymi stosowanymi do osiągnięcia tego celu są studia literaturowe i studium przypadku „MSGO – EcoTech System”. Normy unijne nakładają na państwa członkowskie wysoki poziom odzysku i recyklingu. Oczywiste jest, że w celu spełnienia poczucia sprawiedliwości społecznej, ci, którzy bezpośrednio przyczynili się do tej sytuacji, tj. konsumenci i producenci, również powinni wziąć udział w tych procesach. Producenci potrzebują jednak narzędzi do monitorowania wydajności i skuteczności swoich działań. Przedstawiany „MSGO – EcoTech System” bazuje na systemie zachęt. U jego postaw leży założenie, iż firmy, które deklarują w swojej strategii biznesu społeczną odpowiedzialność przyłączą się aktywnie tworząc system zachęt. Przykład pokazuje, ze istnieją nowoczesne rozwiązania, które mogą wspomóc firmy w realizacji EPR. Uzyskane wyniki dostarczają wskazówek dla przedsiębiorstw szukających rozwiązań w tym zakresie.
EN
The synthesis and physicochemical properties of vanadium(III,IV,V) complexes with Schiff base ligands based on 3,5-dibromo-4-methoxy-salicylaldehyde and phenylacetic hydrazide (H2L1), 5-chlorosalicylaldehyde and 4-hydroxybenzhydrazide (H2L2) and 5- chlorosalicylaldehyde and 2-hydroxybenzhydrazide (H2L3) were presented. The formulas of the complexes {[V(L1)(HL2)]·EtOH (1), [VO(L2)(phen)]·2H2O (2) and [VO(L3)(EtO)] (3)} were proposed based on the elemental analysis, IR and UV-Vis spectra. Additionally, the IR and UV-Vis spectra (in solvents as well as in a solid state) have been discussed from the vanadium oxidation state point of view. The single crystal structure of 3 shows triclinic, P-1 space group, structure is stabilized by hydrogen bonds and strong π-π stacking interactions. The oxidation state of the metal centre was also confirmed by the magnetic susceptibility measurements. The stability of the complexes was measured in pH = 7.00 and in pH = 2.00 which allows to evaluate the use of these compounds as insulin mimetic compounds.
PL
W artykule, na przykładzie fińskiej spółki TVO, została zaprezentowana jedna z metod finansowania projektów inwestycyjnych w energetyce jądrowej, tzw. model Mankala. Przedstawiony jest krótki opis modelu, historia powstania spółki, zasady jej funkcjonowania, realizowane inwestycje oraz plany rozwojowe.
EN
This paper presents one of the methods of financing investment projects in nuclear power sector, the so-called Mankala model, based on example of Finnish company TVO. The Authors presented a short description of the model, history of the company and rules of its functioning, ongoing projects as well as development plans.
5
EN
The stable EPR signal produced by ionizing radiation in crystalline D-mannose (C6H12O6) and separated from cranberries (Vaccinium oxycoccus) was studied. The isothermal heating of irradiated sample at 95°C for 10 minutes (melting point of D-mannose is 132°C) resulted in the modifi cation and simplifi cation of the EPR signal involved. The isotropic quartet has been recognized in the EPR signal of heat-treated sample. Molecular structure of the isotropic quartet identifi ed in the complex EPR signal of D-mannose crystallite is proposed.
EN
A robust and highly imperceptible audio watermarking technique is presented to secure the electronic patient record of Parkinson’s Disease (PD) affected patient. The proposed DCT-SVD based watermarking technique introduces minimal changes in speech such that the accuracy in classification of PD affected person’s speech and healthy person’s speech is retained. To achieve high imperceptibility the voiced part of the speech is considered for embedding the watermark. It is shown that the proposed watermarking technique is robust to common signal processing attacks. The practicability of the proposed technique is tested: by creating an android application to record & watermark the speech signal. The classification of PD affected speech is done using Support Vector Machine (SVM) classifier in cloud server.
7
Content available The cost of new nuclear in France
EN
The French Nuclear Society presents the main points of nuclear program in France until 2050 based on III generation reactors. The development will be based on replacement of existing reactors by new EPR reactors. During the implementation of the program the experience gained in the recent construction and putting into operation of such blocks in the world (e.g. in Finland, France and China) will be used, which would lead to reduction of investment cost.
PL
Francuskie Stowarzyszenie Energii Nuklearnej (SFEN) przedstawia wizję rozwoju programu energetyki jądrowej we Francji do 2050 r. w oparciu o reaktory III generacji. Zachodzące zmiany polegać będą na zastępowaniu istniejących bloków przez reaktory EPR. Przy jego realizacji będzie wykorzystane doświadczenie z obecnie budowanych i uruchamianych bloków EPR na świecie (Finlandia, Francja i Chiny) co pozwoli to na redukcję kosztów inwestycyjnych.
8
Content available Koszt nowej energetyki jądrowej we Francji
PL
Francuskie Stowarzyszenie Energii Nuklearnej (SFEN) przedstawia wizję rozwoju programu energetyki jądrowej we Francji do 2050 r. w oparciu o reaktory III generacji. Zachodzące zmiany polegać będą na zastępowaniu istniejących bloków przez reaktory EPR. Przy jego realizacji będzie wykorzystane doświadczenie z obecnie budowanych i uruchamianych bloków EPR na świecie (Finlandia, Francja i Chiny) co pozwoli to na redukcję kosztów inwestycyjnych.
EN
The French Nuclear Society presents the main points of nuclear program in France until 2050 based on III generation reactors. The development will be based on replacement of existing reactors by new EPR reactors. During the implementation of the program the experience gained in the recent construction and putting into operation of such blocks in the world (e.g. in Finland, France and China) will be used, which would lead to reduction of investment cost.
PL
Energetyka jądrowa rozwija i doskonali technologię reaktorów już od sześciu dekad. Dlatego rozróżnia się kilka generacji reaktorów jądrowych, z których każda wyróżnia się innymi cechami związanymi z projektem, kwestiami bezpieczeństwa, czy wykorzystaniem paliwa jądrowego. Zdecydowana większość reaktorów obecnie eksploatowanych na świecie została zbudowana w latach 70. i 80. XX wieku. Są to reaktory II generacji. Program Polskiej Energetyki Jądrowej zakłada budowę elektrowni jądrowych generacji III/III+. Rynek oferuje kilka konkretnych technologii tej generacji. W niniejszym artykule prezentowane są informacje o czterech z nich – trzech reaktorach wodnych ciśnieniowych – AP1000, APR1400 oraz EPR, a także jednym reaktorze wodnym wrzącym – ABWR. Artykuł zawiera informacje zebrane na potrzeby jednego z tematów realizowanych przez autorów w Narodowym Centrum Badań Jądrowych.
EN
Nuclear Power Industry has been developing and improving reactor technology for six decades. The history of reactors development is divided into several generations that differ in their design, approach to safety issues, utilization of nuclear fuel and so on. The vast majority of reactors, currently in operation in the world, was built in the 1970s and 1980s. They are considered as the second generation reactors. The Polish Nuclear Power Programme assumes construction of NPP of III/III+ generation. Several technologies are available on the market. In the current paper the information on four of them is contained – three of PWR type – AP1000, APR1400 and EPR, and one of BWR type – ABWR. The information in this article has been compiled for the needs of one of the topics performed at National Centre for Nuclear Research.
10
Content available remote Nano-structured (Mo,Ti)C-C-Ni magnetic powder
EN
Purpose: The paper presents the results of phase composition and magnetic properties of Mo-Ni-Ti-C nanostructured powders. The aim of this research is understanding the correlation between key magnetic properties and the parameters that influence them in the nanostructured powders from Mo-Ni-Ti-C system. Design/methodology/approach: The powder samples were synthesised using modified sol-gel method. Obtained powder were subjected for composition and magnetic properties in a wide temperature range by means of Electron Paramagnetic Resonance (EPR) and magnetic susceptibility measurements. To study the phase composition X-ray diffraction were performed. The morphology of the powders were investigated by scanning electron microscopy (SEM). Findings: Different kinds of structural and magnetic phases have been found in the investigated compounds, e.g. (Mo, Ti)C, C, Ni. It was found that such different phases create different kinds of magnetic interactions, from paramagnetic, antiferromagnetic up to superparamagnetic. Significant magnetic anisotropy has been revealed for low temperatures, which lowers with temperature increase. Moreover, non-usual increasing of the magnetization as a function of temperature was observed. It suggests, that overall longrange AFM interaction may be responsible for the magnetic properties. Research limitations/implications: For the future work explanation which phases in Mo-Ni-Ti-C system are responsible for different kinds of magnetic interactions are planned. Practical implications: The composition of different kinds of phases may be controlled to tune magnetic properties of the nanostructured Mo-Ni-Ti-C systems. Originality/value: In this study, for the first time Mo-Ni-Ti-C nanostructured samples were prepared with different kinds of structural and magnetic phases, creating different kinds of magnetic interactions, from paramagnetic, antiferromagnetic up to superparamagnetic-like. The latter seems to be formed due to the presence of magnetic nanoparticles and longrange antiferromagnetic interactions dominating in the whole temperature range.
11
Content available remote Structural and luminescent properties of Fe3+ doped PVA capped CdTe nanoparticles
EN
During recent decades, magnetic and semiconductor nanoparticles have attracted significant attention of scientists in various fields of engineering, physics, chemistry, biology and medicine. Fe3+ doped PVA capped CdTe nanoparticles were prepared by co-precipitation method and characterized by powder X-ray diffraction, SEM, TEM, FT-IR, optical, EPR and PL techniques to collect the information about the crystal structure, coordination/local site symmetry of doped Fe3+ ions in the host lattice and the luminescent properties of prepared sample. Powder XRD data revealed that the crystal structure belongs to a cubic system and its lattice cell parameters were evaluated. The average crystallite size was estimated to be 8 nm. The morphology of prepared samples was analyzed by using SEM and TEM investigations. Functional groups of the prepared sample were observed in FT-IR spectra. Optical absorption and EPR studies have shown that on doping, Fe3+ ions enter the host lattice in octahedral site symmetry. PL studies of Fe3+ doped PVA capped CdTe nanoparticles revealed UV and blue emission bands. CIE chromaticity coordinates were also calculated from the emission spectrum of Fe3+ doped PVA capped CdTe nanoparticles.
EN
The stable and complex EPR signals produced by the action of ionizing radiation on crystalline L-sorbose (C6H12O6) separated from rowan berries (Sorbus aucuparia) were studied. Isothermal heating of the samples at the temperature close to the melting point of L-sorbose (140°C) results in the modification and simplification of the EPR signal involved. In the EPR signal of heated L-sorbose, the isotropic quartet was distinguished. In the differential spectrum obtained by subtraction of normalized spectra of unheated and heated L-sorbose, the isotropic doublet was identified in addition. The DFT fitting offers the probable assignment of the EPR signals to specifi c radical structures.
EN
The paper presents the results of studies on the influence of the 2010 Vistula flood on the humification process in the bottom sediments of the Goczałkowice Reservoir in southern Poland. Due to its location in the vicinity of farmlands, forests and urbanized areas, the Goczałkowice Reservoir is characterized by amplified and intense humification processes within its sediments. The studies were focused on the determining the influence of the flood wave containing organic and inorganic suspensions on these processes. Humic acids were analyzed using two spectroscopic methods: Electron Paramagnetic Resonance (EPR) and Fourier Transform Infrared Spectroscopy (FT-IR). Application of these methods allowed to determine the values of free radicals and of the g-factor, which are indicators of oxidation, aromatization and maturation of humic acids during the humification process, as well as the value of the 1650/1720 ratio, reflecting the dissociation of the COOH group to COO‾ and the formation of complexes of transitional metals with humic acids during the humification process.
PL
Przedmiotem artykułu jest przedstawienie wyników badań wpływu powodzi, która miała miejsce na rzece Wisła w 2010 roku na zmianę przebiegu procesu humifikacji osadów dennych Zbiornika zaporowego Goczałkowice, leżącego w południowej części Polski. Zbiornik Goczałkowice, ze względu na swoje położenie oraz obecność obszarów rolnych, leśnych i terenów zurbanizowanych charakteryzuje się wzmożonymi i intensywnie przebiegającymi procesami humifikacji kwasów huminowych zawartych w osadach dennych. Przeprowadzone badania miały na celu określić wpływ fali powodziowej, zawierającej organiczne i nieorganiczne zawiesiny na intensyfikację wyżej wymienionego procesu. Kwasy huminowe badano dwoma metodami spektroskopowymi: elektronowego rezonansu paramagnetycznego (EPR) i spektroskopią w podczerwieni połączoną z transformacją Fouriera (FT-IR). W oparciu o te metody wyznaczono wartości stężenia wolnych rodników i wartości parametru g, stanowiące wskaźnik przebiegu procesów utleniania, aromatyzacji i dojrzewania kwasów huminowych w trakcie procesów humifikacji oraz wartości ilorazu 1650/1720, wskazującego na dysocjację grupy COOH do COO‾ tworzenie się kompleksów metali przejściowych.
PL
VI międzynarodowe porównanie wiarygodności trzech najważniejszych metod analitycznych stosowanych do wykrywania napromieniowanej żywności zorganizowano w 2015 r. pod auspicjami Ministerstwa Zdrowia i Hiszpańskiej Agencji Bezpieczeństwa Żywności i Żywienia (AESAN) oraz Krajowego Centrum Żywności (CNA). W badaniu zatytułowanym „Międzynarodowe badanie porównawcze metodami Tl, PSL i EPR, 6 runda” brało udział dziewiętnaście specjalistycznych laboratoriów z kilku krajów europejskich. CNA jest doświadczonym laboratorium, posiadającym akredytację do wykrywania napromieniowanej żywności metodami thermoluminescencji (TL), fotostymulowanej luminescencji (PSL) i spektroskopii elektronowego rezonansu paramagnetycznego (EPR). Większość laboratoriów uczestniczących w porównaniu międzylaboratoryjnym posiada również taką akredytację. Asortyment produktów spożywczych dostępnych na rynku jest coraz szerszy, jednak nie wszystkie z nich są testowane pod kątem ich potencjalnego napromieniowania. Jest to istotny argument przemawiający za udziałem wszystkich laboratoriów w porównaniach międzylaboratoryjnych, takich jak obecnie przeprowadzane.
EN
Under the auspices of the Ministry of Health and the Spanish Agency for Food Safety and Nutrition (AESAN) the National Food Centre (CNA) in 2015 has organised the 6th international exercise for testing the reliability of three most important analytical methods used for the detection of irradiated food. The study named ”Intercomparative exercise for quality assurance on Tl, PSL and EPR Irradiated food detection methods, 6 th Round” assembled nineteen specialized laboratories from several European countries. The organizing institution CNA possess accreditation for the detection of irradiated food and is experienced in thermoluminescence (TL), photostimulated luminescence (PSL) and electron paramagnetic resonance spectroscopy (EPR). It is also the case with most of participating laboratories. Presently the spectrum of food products found in the market is significantly extended and many of this products were not tested or validated whether their radiation treatment is detectable. This is a strong argument for the need of the organization of intercomparative studies as the present one.
EN
The interaction of synthetic dihydroxyphenylalanine (DOPA) melanin (DM) with nitrite ions, NO2 –, in the pH 3.6–7.0 range, has been investigated using electron paramagnetic resonance (EPR). We found that especially at pH <5.5 (from ca. 5.5 to 3.6) the reaction of DM with nitrite generated large quantities of new melanin radicals, which implies the involvement of nitrous acid, HNO2, in the radical formation process. Measurements carried out at constant pH of 3.6 showed that the melanin signal increased together with nitrite concentration, reaching a plateau level which was more than fourfold larger compared to the initial signal amplitude observed in a nitrite-free buffer of the same pH. The effects of nitrite and DM concentrations on the melanin-free radical content were also investigated. It is proposed that the radicals are generated by one electron oxidation of melanin ortho-hydroquinone groups to ortho-semiquinones by HNO2 or related nitrogen oxides such as NO2 • radicals. The possible involvement of nitric oxide (•NO) and peroxynitrite (ONOO–) in DM oxidation was also examined. In air-free solutions, nitric oxide per se did not generate melanin radicals; however, in the presence of oxygen a marked increase in the melanin EPR signal intensity was observed. This result is interpreted in terms of the generation of radicals via the oxidation of DM by peroxynitrite. Our fi ndings suggest that melanin can function as a natural scavenger of nitrous acid and some nitrous acid-derived species. This property may be relevant to physiological functions of melanin pigments in vivo.
17
Content available Growth and EPR properties of ErVO4 single crystals
EN
Single crystals of ErVO4 were grown by the Czochralski method under ambient pressure in a nitrogen atmosphere. Obtained crystals were transparent with strong pink coloring. Electron paramagnetic resonance (EPR) spectra were recorded as a function of the applied magnetic fi eld. Temperature and angular dependences of the EPR spectra of the samples in the 3–300 K temperature range were analyzed applying both Lorentzian– –Gauss approximation for diluted medium and Dyson for dense magnetic medium. EPR-NMR program was done to fi nd local symmetry and spin Hamiltonian parameters of erbium ions.
EN
Free radicals formed during thermal sterilization of eucerinum anhydricum – the pharmaceutical base were examined by an X-band (9.3 GHz) spectrometer. Eucerinum anhydricum was sterilized at different physical conditions according to the Polish Pharmacopeia norms. The samples were heated at temperatures: 160°C (120 min), 170°C (60 min), and 180°C (30 min). The aim of this study is to compare free radical concentration and effect of microwave power on EPR spectra of eucerinum anhydricum base thermally sterilized at different temperatures and periods of time. The effect of time storage on the free radicals in the heated samples was tested. Free radical concentrations in the sample stored 15 min strongly decreased with the increasing of sterilization temperature, probably as the result of recombination. Storage caused strong decrease of free radical concentrations in the samples, probably as the result of interactions with oxygen. It was observed to be independent of sterilization conditions from 2 days of storage and longer. Because of the lowest free radical concentration, for eucerinum anhydricum thermal sterilization at 180°C for 30 min is recommended. The sterilized samples should be stored at inert atmosphere without oxygen molecules. Fast spin-lattice relaxation processes existed in sterilized eucerinum anhydricum. The character of changes of amplitudes and linewidths of EPR lines with increasing of microwave power was the same for different storage times. The parameters of thermal sterilization and storage time influenced free radical concentration in eucerinum anhydricum, but magnetic spin-lattice interactions were unchanged. The usefulness of EPR spectroscopy in optimization of thermal sterilization process of eucerinum anhydricum was confirmed.
EN
Paramagnetic centers in the two exemplary synthetic and natural dental biocompatible materials applied in implantology were examined by the use of an X-band (9.3 GHz) electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra were measured in the range of microwave power 2.2–70 mW. The aims of this work were to compare paramagnetic centers concentrations in different dental biocompatible materials and to determine the effect of microwave power on parameters of their EPR spectra. It is the very fi rst and innovatory examination of paramagnetic centers in these materials. It was pointed out that paramagnetic centers existed in both natural (~1018 spin/g) and synthetic (~1019 spin/g) dental biocompatible materials, but the lower free radical concentration characterized the natural sample. Continuous microwave saturation of EPR spectra indicated that faster spin-lattice relaxation processes existed in synthetic dental biocompatible materials than in natural material. Linewidths (ΔBpp) of the EPR spectra of the natural dental material slightly increased for the higher microwave powers. Such effect was not observed for the synthetic material. The broad EPR lines (ΔBpp): 2.4 mT, 3.9 mT, were measured for the natural and synthetic dental materials, respectively. Probably strong dipolar interactions between paramagnetic centers in the studied samples may be responsible for their line broadening. EPR spectroscopy is the useful experimental method in the examination of paramagnetic centers in dental biocompatible materials.
EN
The difficulty in determining the electron paramagnetic resonance (EPR) line parameters of ferromagnetic semiconductors has been addressed. For these materials, the resonance line is very broad and lies at low resonance fi eld, so that only a part of the line can be detected experimentally. Moreover, the line is of asymmetric (Dysonian) shape as described by the line shape parameter α. We have compared values of line parameters derived by computer fi tting of the whole experimental EPR line to the Dyson function (or modified Dyson function) with the values obtained by applying this procedure to the left and the right half of the line.
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