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PL
Powszechnie stosowane blachy elektrotechniczne stali krzemowej [15, 16] są zorientowane na ziarno (GO – np. blachy transformatorów anizotropowych) lub niezorientowane na ziarno (NGO – np. blachy izotropowe lub generatorowe). Badaniu poddano blachę typu M130 o wymiarach odpowiadających formatowi A4. Oceniano dwa przypadki zmiany naprężenia w stosunku do geometrycznego środka arkusza blachy jak i wąskiego paska zwijanego w okrąg. Wprowadzono założenie, że poza zakresem odkształceń plastycznych w blasze pozostaje naprężenie szczątkowe w procesie produkcji i montażu np. transformatorów czy maszyn. Wskazano, że istnieje jakościowa zależność między wynikami pomiarów a przewidywaniami analitycznymi. Podjęto próby ilościowej analizy naprężenia na drodze symulacji i pomiaru. Badano związek stanu naprężenia ze zmianami parametrów podatności magnetycznej na stan odkształceń czy deformacji (efekt magnetosprężysty Villariego).
EN
Field magnetic susceptibility (MS) and gamma ray spectrometry (GRS) measurements were performed in the Jurassic/Cretaceous boundary interval in the Tré Maroua section (SE France). The 24 m thick section covers the interval from the upper Tithonian magnetozone M20n (Chitinoidella Zone) to the lower Berriasian M17r magnetozone (Calpionella elliptica Subzone). The micritic limestones reveal a very low content of terrigenous impurities (0.0-0.2% K and 0.2-2.0 ppm Th) and low MS values (-5 to 15 × 10-6 SI). Despite low intensity of both MS and GRS signal, a consistent trend of terrigenous input is observed: decreasing values in the upper Tithonian and increasing tendency in the upper part of the lower Berriasian. The long-term trends are quite similar to those documented in some Western Tethyan sections and the Polish Basin, indicating that variations of terrigenous input might be controlled by large-scale palaeoclimatic variations and relative sea-level changes. Decrease of Conusphaera and increase of Nannoconus frequencies fall in the lower part of M19n2n in the uppermost Tithonian. These events correlate with large decrease of terrigenous input and widespread oligotrophication in the Western Tethyan domain.
EN
Measurements of the magnetic susceptibility (MS) in sedimentary sequences can quickly provide information on the variability of their mineral composition. A typical application of MS is the reconstruction of the supply of terrigenous material in car¬bonate rocks or the variability of the ratio of ferromagnetic to paramagnetic /diamagnetic minerals in clastic rocks. The article discusses the practical aspects of using the Bartington's portable apparatus for magnetic susceptibility probing along with the correlation of these results with the mineral composition obtained from X-ray diffraction tests. The analysed rock material was red and green clays from the vicinity of Częstochowa, assigned to the mud-evaporite Ozimek Member, Grabowa Formation (Keuper facies, Upper Triassic). The obtained results indicate the possibility of a correlation between the MS and the composition of rock-forming minerals in the studied sediments, where in green clays the magnetite/maghemite with pyrrhotite(?) does not substantially affect the MS, and para- and/or diamagnetic minerals have a decisive role. In the red clays the dominant MS carrier is the hematite.Measurements of the magnetic susceptibility (MS) in sedimentary sequences can quickly provide information on the variability of their mineral composition. A typical application of MS is the reconstruction of the supply of terrigenous material in car¬bonate rocks or the variability of the ratio of ferromagnetic to paramagnetic /diamagnetic minerals in clastic rocks. The article discusses the practical aspects of using the Bartington's portable apparatus for magnetic susceptibility probing along with the correlation of these results with the mineral composition obtained from X-ray diffraction tests. The analysed rock material was red and green clays from the vicinity of Częstochowa, assigned to the mud-evaporite Ozimek Member, Grabowa Formation (Keuper facies, Upper Triassic). The obtained results indicate the possibility of a correlation between the MS and the composition of rock-forming minerals in the studied sediments, where in green clays the magnetite/maghemite with pyrrhotite(?) does not substantially affect the MS, and para- and/or diamagnetic minerals have a decisive role. In the red clays the dominant MS carrier is the hematite.
4
EN
This work presents a method for measuring the magnetic susceptibility of soil samples based on interactions of magnetic particles contained in a tested sample with a weighed permanent magnet placed in the balance mechanical design. The MYA 2.4Y microbalance manufactured by Radwag Wagi Elektroniczne, Poland, was used to perform mass measurements. The weighing system was adjusted for mass indication using a certified mass standard, and for magnetic susceptibility indication using a certified magnetic susceptibility standard. The volume of each analysed soil sample was 3.93 cm3 and was similar to the volume and the size of the magnetic susceptibility standard. The research was carried out for 10 soil samples with a magnetic susceptibility range varying from 20 to 1600x10-8 m3 kg-1. The soil samples contained technogenic magnetic particles and particles of natural magnetite of geogenic origin. The study was performed for a field of 2 mT.
EN
The paper presents selected aspects of calculations and modelling of variograms from measurements of soil surface magnetic susceptibility for rapid screening of surface soil contamination with Technogenic Magnetic Particles (TMP). In particular, the methodology of variogram analysis in the case of multiple magnetometric measurements in one measurement location with the use of the MS2D Bartington sensor was discussed. A new approach to analysing such measurements was proposed that allows determining and using the nugget effect from standard, already existing measurements. This is of key importance for the quality of spatial analyses, and thus the screening results obtained by means of field magnetometry. In the paper, it was shown, step by step, that averaging the measurements performed at one measurement point during the calculation of the empirical variograms does not result in the loss of information on spatial variability in the microscale. As it was calculated non-averaged measurements were characterised by the nugget-to-sill ratio of about 96 % which was much higher than in the case of averaged measurements (close to 0 %). A range of correlation was similar in both cases and was equal to about 300 m - 400 m. The local variogram revealed a range of correlation of about 80 cm. As a result, the screening results are more reliable than is the case with the traditional procedure. An additional advantage of the work was the performance of all calculations in free R software.
EN
The article concerns the research on the properties of core-shell superparamagnetic nanoparticles in the context of their use in medicine for diagnostics and therapy. The article presents a system for impedance (AC) spectroscopy of nanoparticles with a new arrangement of receive coils. A significant modification was the position of the reference coil in relation to the receive coils as well as the method of winding and routing the wires on the carcass. The 3D printing technique was used in the production of the measuring coil system. The aim of the work was to experimentally verify the developed measurement system and analyze its properties. The system tests were carried out at low frequencies ranging from 2 to 50 kHz. Complex magnetic susceptibility was measured for superparamagnetic iron oxide nanoparticles in polymer shells in a physiological saline solution. The obtained results confirmed the relevance of the concept of the measurements. In summary, the observed properties of the realized system are discussed and further directions of its development are proposed.
PL
Artykuł dotyczy badań właściwości nanocząstek superparamagnetycznych typu rdzeń-powłoka w kontekście wykorzystania ich w medycynie do diagnostyki jak i terapii. W artykule przedstawiono układ do spektroskopii impedancyjnej (AC) nanocząstek z nowym układem cewek odbiorczych. Istotną modyfikacją była pozycja cewki referencyjnej względem cewek odbiorczych jak również sposób nawijania i prowadzenia przewodów na karkasie. W realizacji układu cewek pomiarowych wykorzystana została technika druku 3D. Celem pracy była eksperymentalna weryfikacja opracowanego układu pomiarowego i analiza jego własności. Testy układu zostały przeprowadzone dla niskich częstotliwości w zakresie od 2 do 50 kHz. Pomiary zespolonej podatności magnetycznej dokonano dla nanocząstek superparamagnetycznych tlenku żelaza w otoczkach polimerowych w roztworze soli fizjologicznej. Uzyskane wyniki potwierdziły poprawność koncepcji realizacji pomiarów. W podsumowaniu omówiono zaobserwowane własności zrealizowanego układu i zaproponowano dalsze kierunki jego rozwoju.
EN
Magnetic susceptibility measurements remain one of the most reliable methods used to investigate the pollution of both surface and subsurface soil from metallic anthropogenic sources. Most of the geological rocks within the study area increase the susceptibility of the soil; however, knowing the natural background susceptibility of the parent rocks will give an idea of the anthropogenic influence on the susceptibility of the soil. This study was carried out in Kogi State, North Central Nigeria, with the aim of determining the depth of the boundary between the anthropogenic influences on soil magnetic susceptibility from those of a lithogenic origin. Magnetic susceptibility measurements were carried out on 1,760 soil samples, collected from 220 soil profiles at a depth of 80.0 cm and at intervals of 10.0 cm. From the spatial distribution of magnetic susceptibility maps at different depths, the boundary between the basement complex and the sedimentary basin was clearly demarcated. The result further shows the highest magnetic susceptibility values of 350–650 × 10−5 SI, which dominates the surface soil to a depth of 40.0 cm. At the depth of 40–50 cm, the result indicates the combination of a natural anthropogenic influence on soil magnetic susceptibility with an average of 250 × 10−5 SI. Furthermore, no evidence of layering along the depth sections was observed, suggesting that the soil profiles indicate areas mainly covered by anthropogenically influenced susceptibility, which were localized and restricted to commercial places within the state. This study reveals that the average depth of soil affected by anthropogenic pollutants is between 40–50 cm in commercial places and 20–30 cm in other places with less commercial activities.
EN
We provide a revised magnetostratigraphy and magnetic susceptibility stratigraphy of the most complete and thickest (to nearly 60 m) loess-palaeosol sequences in Ukraine spanning the past 1 My: the Roksolany (Black Sea Lowland) and Vyazivok (Dnieper Lowland) sections. The Matuyama-Brunhes boundary has been detected in both sequences in stratigraphically different palaeosol units according to current regional chronostratigraphic schemes. Hypotheses of a large magnetic lock-in depth at Vyazivok and lithostratigraphic incompleteness at Roksolany do not resolve this inconsistency. Instead, new chronostratigraphic models following the Chinese loess designation system, which are supported by correlation of the magnetic susceptibility records with the marine isotope record and estabilished magnetostratigraphic control points, are proposed. We conclude that the Matuyama-Brunhes reversal in the Roksolany and Vyazivok sections belongs to the same palaeosol unit, the Shyrokyne (according to our nomenclature, the U-S7), which corresponds to MIS 19. This novel interpretation resolves the inconsistency of the stratigraphic position of the Matuyama-Brunhes boundary in Ukrainian loess, ends long-standing debate regarding the chronostratigraphy of the Roksolany section, and allows precise correlation of the most representative loess-palaeosol sequences of Ukraine with those in the Danube Basin and the Chinese Loess Plateau. It is considered that the Roksolany Tephra in MIS 6 loess unit can be related to the L2 Tephra which is widely distributed in southeastern European loess records and lacustrine archives. In the light of our results, the Roksolany sequence may serve as a national lectostratotype of the Middle Zavadivka (U-L4) loess unit corresponding to MIS 10. Additionally, a generalized pedostratigraphic column of the past 1 My for central and southern Ukraine has been constructed and correlated with the Hungarian, Serbian and Chinese loess stratigraphies, as well as with the marine isotope record down to MIS 25.
EN
Soil contamination with rare earth metals (REE) can have both direct and indirect connection with industrial activity and ore-exploration. In the studies conducted so far, the presence of rare earth elements in coal seams, coal combustion waste as well as fly ash was found. It is important that detailed studies of the REE content in soil were not carried out in Poland. Until now, in a few studies, a high content of cerium and lanthanum was found in relation to the average content of the torn ones in the world. This work focuses on the areas under the influence of the industry associated with the extraction and combustion of hard coal, but also with other types of industry. Analyzes of REE content in soil were conducted in selected areas of the Upper Silesian Industrial Region and Norway, located near the Bjornevatn mine. In study areas, soil samples were collected and used for chemical and magnetometric measurements. Firstly, concentrations of REE were determined, and after that soil samples were used to measure soil magnetic susceptibility. Finally, statistical analyses were performed in order to check the correlation between REE concentrations in soil and soil magnetic susceptibility.
EN
Magnetic susceptibility measurements were taken in eight selected streets of Opole, with diversified vehicle traffic intensity. The experiment surfaces were marked on every street, with two separate zones: A – a strip directly adjacent to the road and B – a strip 1 m away from the road edge. The carried out research indicated considerable influence of communication-generated pollution, with simultaneous influence of other local emission sources. The relation of magnetic anomalies was indicated, which may be the result of ferromagnetic materials aggregation, originating mainly from combustion processes. The road structure, including the surface condition, the main construction material and susceptibility of the surface to cracking are equally important when considering the magnetic increase. A considerable variation of magnetic measurements in different season was pointed out; however, the largest median values of magnetic susceptibility were recorded in the summer season.
EN
Measurement of magnetic susceptibility of topsoil represents a very useful tool for the detection of atmospherically deposited magnetic particles. The samples of forest soils from the Moravian-Silesian Beskydy Mountains (the Czech Republic) were used for identification of emissions sources of particles with magnetic ordering. Magnetic susceptibility was measured at bulk samples of grain size class under 2 mm. Microanalysis using electron microscope with an energy dispersive X-ray spectrometer was used for the determination of particles in the magnetic fraction. The samples of dust from the sintering plant of the Iron Works in the town of Třinec were analysed. The values of magnetic susceptibility of forest soils in the Třinec region are increased. In the relatively near vicinity of the industrial area, the average value for Javorový Mount was 7.90×10-6 m3/kg, for Ostrý Mount it was 6.69×10-6 m3/ kg. It was proved that they were higher than the average values from the Beskydy Mountains (4.64×10-6 m3/kg). The concentrations of lead and magnetic susceptibility in soils showed significant correlation dependence (rs = 0.85). The iron and steel industry represent the primary source of the pollution load in forest soils of the studied area. Statistically, significant dependences between the organic matter content and the lead and zinc concentrations as well as between the magnetic susceptibility values and the iron concentrations in forest soils were found. It was confirmed that the airborne particles are deposited on vegetation and accumulated in the organic horizon of forest soils.
PL
Pomiar podatności magnetycznej wierzchniej warstwy gleby stanowi bardzo przydatne narzędzie do wykrywania osadzonych z atmosfery cząstek magnetycznych. Próbki gleb leśnych z Beskidu Morawsko-Śląskiego (Czechy) wykorzystano do identyfikacji źródeł emisji cząstek o właściwościach magnetycznych. Podatność magnetyczną mierzono w próbkach zbiorczych w klasie ziarnowej poniżej 2 mm. Mikroanaliza z użyciem mikroskopu elektronowego ze spektrometrem dyspersyjnym energii rentgenowskiej została użyta do oznaczenia frakcji magnetycznej cząstek. Przeanalizowano próbki pyłu ze spiekalni Huty Żelaza w Trzyńcu. Stwierdzono wzrost wartość podatności magnetycznej gleb leśnych w regionie Trzyńca. W stosunkowo bliskim sąsiedztwie obszaru przemysłowego Javorový Mount średnia wartość wynosiła 7,90 × 10-6 m3/kg, w przypadku Ostrý Mount 6,69 × 10-6 m3/kg. Wykazano, że były one wyższe niż średnie wartości dla Beskidów (4,64 × 10-6 m3/kg). Zawartość ołowiu i podatność magnetyczna w glebach wykazały istotną korelację (rs = 0,85). Hutnictwo żelaza i stali stanowi główne źródło ładunku zanieczyszczeń w glebach leśnych badanego obszaru. Stwierdzono statystycznie istotne zależności między zawartością materii organicznej a stężeniem ołowiu i cynku, a także między wartościami podatności magnetycznej a stężeniami żelaza w glebach leśnych. Potwierdzono, że zawieszone w powietrzu cząstki osadzają się na roślinności i gromadzą się w organicznym horyzoncie gleb leśnych.
12
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.
EN
Sand dunes are the most prominent subjects of geological and geomorphological interest along the Curonian Spit - a mega-barrier that separates the Curonian Lagoon from the Baltic Sea. To date, an assessment of various parameters of migrating dunes along the spit has been based on comparative analysis of old maps or aerial and satellite images, as well as geodetic measurements. These investigations have allowed assessment of dune dynamics over a relatively short historical period (~1700s to present). The most recent detailed investigations of the Dead (Grey) Dunes along the Lithuanian part of the spit using ground-penetrating radar (GPR) and magnetic susceptibility (MS) surveys, supported by a radiocarbon (14C) chronological framework of palaeosols and infrared optically stimulated luminescence (IR-OSL) ages of sand horizons, have advanced our understanding of aeolian landscape evolution. The interpretation of dune activity and stability phases has been generally based on IR-OSL dating results of the sand layers located between radiocarbon-dated palaeosols. However, the influence of soil-forming processes on the IR-OSL dating results related to possible migration of natural radioactive isotopes via aeolian sand layers has not been previously considered. Hypotheses of dune reactivation and migration caused by abrupt regional climate shifts, catastrophic forest fires, anthropogenic influence, and more local forcings have been tested. An integrated approach to dune investigations has offered an estimate of the rates of sand accumulation and key phases of aeolian dynamics during both stormy and calm periods, as well as helped to extend the record of dune evolution to the mid-Holocene. The palaeoenvironmental and palaeodynamic reconstructions of the Dead Dunes suggest that this mid-Holocene phase of dune activity was of a local character and likely did not exceed several centuries.
EN
Soil magnetometry, based on topsoil magnetic susceptibility measurement, has been proven in the literature to be very useful and increasingly applicable screening technique of soils affected by anthropogenic pressure. According to the literature data, this method requires further improvement, especially in the field of magnetometric imaging techniques. The aim of the study was assessment of magnetic transformations of soils in the city of Opole (Opolskie Voivodeship) using soil magnetometry and three magnetometric data interpolation techniques (natural neighbour NN, inverse distance weightening IDW and ordinary kriging OK). The data was collected during field measurements of magnetic susceptibility, carried out in an area of 7.1 km2, in a network of 124 measurement points, in the year 2015. The location of the points was determined using the Garmin GPS GPSMap 64st device, and the magnetometric measurements were performed in situ using the MS2 meter and the MS2D sensor from Bartington Instruments. The research showed high values of magnetic susceptibility and occurrence of soil magnetic anomalies in the study area. This was accompanied by geochemical transformations of soils, revealed in previous research. The results suggest that it could be caused by the long-term deposition of cement dusts, emitted in increased quantities in former times by the cement plant, which has left its footprint in the environment. When analyzing the usefulness of the magnetometric data interpolation techniques, the IDW technique best reflected the spatial distribution of magnetic susceptibility in the study area, while the technique of OK, due to the so-called smoothing effect, turned out to be less useful.
PL
Magnetometria glebowa, polegająca na pomiarze podatności magnetycznej wierzchniej warstwy gleby, jest bardzo przydatną i coraz powszechniej stosowaną techniką monitorowania stanu gleb objętych wpływem antropopresji. Jak wynika z danych literaturowych, metoda ta wymaga dalszego udoskonalania, szczególnie w zakresie technik obrazowania danych magnetometrycznych. Celem badań była ocena przekształceń magnetycznych gleb na terenie miasta Opola (woj. opolskie) z zastosowaniem magnetometrii glebowej oraz trzech technik interpolacji danych magnetometrycznych (naturalnego sąsiedztwa NN, ważonych odwrotnych odległości IDW oraz krigingu zwykłego OK). Dane zostały zgromadzone podczas pomiarów terenowych podatności magnetycznej, wykonanych na powierzchni 7,1 km2, w sieci 124 punktów pomiarowych, w 2015 r. Lokalizacje punktów określono za pomocą urządzenia Garmin GPS GPSMap 64st, a pomiary magnetometryczne wykonano in situ za pomocą miernika MS2 i czujnika MS2D firmy Bartington Instruments. Badania wykazały wysokie wartości podatności magnetycznej oraz występowanie glebowych anomalii magnetycznych na badanym terenie. Towarzyszą temu przekształcenia geochemiczne gleb, wykazane we wcześniejszych badaniach. Wyniki sugerują, że przyczyną tego stanu mogła być długoletnia depozycja pyłów cementowych, emitowanych w latach ubiegłych w zwiększonej ilości przez cementownię, która pozostawiła swój ślad w środowisku. Analizując przydatność zastosowanych technik interpolacji danych magnetometrycznych, technika IDW najlepiej odzwierciedlała rozkład przestrzenny podatności magnetycznej na badanym terenie, podczas gdy technika OK, z powodu tzw. efektu wygładzającego, okazała się mniej przydatna.
EN
Several samples of dusts from steel and coke plants (collected mostly with electro filters) were subjected to the investigation of content of mineral phases in their particles. Additionally, sample of bog iron ore and metallurgical slurry was studied. Next, the magnetic susceptibility of all the samples was determined, and investigations of iron-containing phases were performed using transmission Mössbauer spectrometry. The values of mass-specific magnetic susceptibility  varied in a wide range: from 59 to above 7000 × 10−8 m3kg−1. The low values are determined for bog iron ore, metallurgical slurry, and coke dusts. The extremely high  was obtained for metallurgical dusts. The Mössbauer spectra and X-ray diffraction patterns point to the presence of the following phases containing iron: hematite and oxidized magnetite (in coke and metallurgical dusts as well as metallurgical slurry), traces of magnetite fi ne grains fraction (in metallurgical dusts), amorphous glassy silicates with paramagnetic Fe3+ and Fe2+ ions, traces of pyrrhotite (in coke dusts), α-Fe and nonstoichiometric wüstite (in metallurgical slurry), as well as ferrihydrite nanoparticles (in bog iron ore). For individual samples of metallurgical dusts, the relative contributions of Fe2+/3+ ions in octahedral B sites and Fe2+ ions in tetrahedral A sites in magnetite spinel structure differs considerably.
EN
Composites with a 90%Pb(TixZr1–xO3)-10%NiFe1.98Co0.02O4 composition have been synthesized. It has been established that the polarization of samples resulting from exposure to an electric field for 1 hour of 4 kV/mm in strength at a temperature of 400 K leads to crystal structure deformation. The compression of elementary crystal cells in some areas during polarization of the sample creates conditions suitable for the enhancement of magnetic exchange interactions. It has been found that the polarization process of such compositions leads to increases in specific magnetization and magnetic susceptibility. The analysis of Mössbauer spectra has shown that the polarization of the 90%Pb(TixZr1–xO3)-10%NiFe1.98Co0.02O4 composite leads to significant changes in the effective magnetic fields of iron subspectra in various positions.
PL
W pracy przedstawiono wyniki badań własności magnetooptycznych szkieł tellurowych 70TeO2-5X-10P2O5-10ZnO-5PbF2 (X = MgO, Bi2O3). Badania przeprowadzono dla czystych matryc szkieł syntezowanych z użyciem różnych modyfikatorów oraz szkieł dodatkowo domieszkowanych jonami erbu Er3+. Celem domieszkowania jonami paramagnetycznego pierwiastka z grupy lantanowców była próba uzyskania w badanych materiałach większych wartości stałej Verdeta. W oparciu o pomiary stałopolowej podatności magnetycznej z użyciem magnetometru wibracyjnego oceniono własności magnetyczne szkieł, określając dominujący rodzaj uporządkowania magnetycznego. Otrzymane wyniki badań wskazują na paramagnetyczny charakter uporządkowania magnetycznego w badanych szkłach. Domieszkowanie szkła paramagnetycznymi jonami Er3+ powodowało zwiększenie wartości ich podatności magnetycznej, co sugeruje możliwość obserwacji lepszych własności magnetooptycznych. Własności magnetooptyczne szkieł tellurowych określono w oparciu o pomiary efektu Faradaya i obliczenia wartości stałej Verdeta dla różnych długości fali spolaryzowanego światła. Uzyskane wyniki potwierdzają polepszenie się własności magnetooptycznych badanych szkieł pod wpływem domieszkowania jonami erbu. Dla wielu długości fal zaobserwowano wyższe wartości kąta skręcenia płaszczyzny polaryzacji światła pod wpływem wzdłużnego pola magnetycznego. Obliczone na tej podstawie wartości stałej Verdeta wykazują istotny wzrost wywołany domieszkowaniem i uzyskane wartości są porównywalne do parametrów obserwowanych w szkłach tellurowych modyfikowanych lantanem. Prezentowane wyniki mogą być istotne dla opracowania nowych materiałów na bazie szkieł tellurowych do zastosowań w urządzeniach optoelektronicznych wykorzystujących efekt Faradaya.
EN
The paper presents the results of investigations of the magnetooptic properties of 70TeO2-5X-10P2O5-10ZnO-5PbF2 (X = MgO, Bi2O3) telluric glasses. Tests were conducted for clean matrices of glasses synthesized using various modifiers and glasses additionally doped with Er3+ erbium ions. The purpose of doping with paramagnetic ions from the lanthanide group was an attempt to obtain higher Verdet constant values in the materials studied. Based on measurements of permanent magnetic susceptibility with a vibration magnetometer, the magnetic properties of the glasses were determined, defining the dominant type of magnetic arrangement. The obtained results indicate the paramagnetic character of the magnetic order in the examined glass. The uptake of Er3+ ions into paramagnetic glass increased the value of their magnetic susceptibility, suggesting the possibility of observing improved magnetooptic properties. The magneto-optical properties of telluric glasses were determined based on Faraday effect measurements and the calculation of the Verdet constant values for different wavelengths of polarized light. The results confirm the improvement of magnetooptical properties of the examined glasses under the effect of doping with erbium ions. For many wavelengths, the values of the polarization angle of the light were observed as a result of the longitudinal magnetic field. The Verdet constant values calculated on this basis show significant increase due to doping and the resulting values are comparable to the parameters observed in lanthanum-type tellurium glasses. The presented results may be important for the development of new materials based on telluric glasses for optoelectronic devices using the Faraday effect.
EN
Magnetic materials may be added to the fracturing fluid, as the magnetic marker allowing to determine the range and efficiency of hydraulic fracturing. The application of appropriate magnetic markers can significantly improve the efficiency of shale gas extraction. There are, however, other important benefits of magnetic markers use, involving the monitoring of environmental pollution, during gas extraction with above mentioned method. However, with the rapid increase in amount of shale gas extracted using hydraulic fracturing method, there are also credible reports on the possibility of groundwater or the soil pollution. Thus, it is necessary to apply enhanced methods, to effectively detect any fracturing fluid leakage. The use of magnetic markers gives such opportunities. In case of leakage and consequently the fracturing fluid pollution, magnetic markers are placed into the soil environment. The presence of pollutants in soil can be detected using a number of standard chemical methods, but magnetometric ones, which are much faster and cheaper deserve special attention, because they enable in-situ detection of the magnetic marker in fracturing fluid leakage. This article discusses the above-mentioned issues based on the literature review, the knowledge and experience of the authors.
PL
Materiały magnetyczne dodawane do płynu szczelinującego jako marker magnetyczny, mogą w procesie szczelinowania hydraulicznego pełnić dodatkowe funkcje, oprócz umożliwienia określenia zasięgu szczelin w skałach złożowych wytwarzanych w tym procesie. Ocenia się, że zastosowanie odpowiednich markerów magnetycznych może znacznie poprawić wydajność wydobycia gazu łupkowego. Istnieją jednakże inne, istotne korzyści z zastosowania markerów magnetycznych, polegające na monitoringu zanieczyszczenia środowiska w trakcie wydobycia gazu łupkowego omawianą metodą. Niestety, wraz z gwałtownym wzrostem ilości wydobywanego gazu łupkowego, z zastosowaniem metody szczelinowania hydraulicznego, pojawiły się również wiarygodne doniesienia o możliwości zanieczyszczenia wód podziemnych lub gleby, w trakcie tego procesu. Konieczne jest więc zastosowanie skutecznych metod wykrywania potencjalnego wycieku płynu szczelinującego. Stosowanie markerów magnetycznych daje takie możliwości. W przypadku wystąpienia wycieku i w konsekwencji zanieczyszczenia środowiska płynem szczelinującym, również markery magnetyczne zostają wprowadzone do środowiska gruntowego. Obecność zanieczyszczeń w gruncie można stwierdzić za pomocą wielu standardowych metod chemicznych. Ze względu na znaczną czasochłonność i kosztochłonność bezpośrednich metod laboratoryjnych, na uwagę zasługują znacznie szybsze i tańsze metody magnetometryczne, które pozwalają na łatwe, in-situ, wykrycie markera magnetycznego w ewentualnym wycieku. W artykule omówione zostaną wspomniane powyżej zagadnienia na podstawie przeglądu literaturowego oraz wiedzy i doświadczenia autorów.
EN
This paper presents the results of investigations into the microstructure and magnetic properties of Fe86Zr7Nb1Cu1B5, Fe82Zr7Nb2Cu1B8 and Fe81Pt5Zr7Nb1Cu1B5 alloys. The alloys were investigated in their as-quenched state, in the form of thin ribbons with approximate dimensions as follows: width 3 mm and thickness 20 μm. The investigations were performed utilizing Mössbauer spectrometry and X-ray diffractometry. Also, an evaluation of the low-field magnetic susceptibility and measurements of the magnetization versus temperature and magnetizing field were performed.
20
Content available remote The magnetic susceptibility of soils in Kraków, southern Poland
EN
Studies into the magnetic susceptibility have been used to assess the soils contamination in the Krakow area. The results of topsoil (over a 2 × 2 km grid), subsoil (37 shallow holes) and soil samples (112) measurements were presented as maps of soil magnetic susceptibility (both volume and mass) illustrating the distribution of parameters in topsoil horizon (0–10 cm) and differential magnetic susceptibility maps between topsoil horizon and subsoil (40–60 cm). All evidence leads to the finding that the highest values of magnetic susceptibility of soil are found exclusively in industrial areas. Taking into consideration the type of land use, the high median value (89.8 × 10−8 m3kg−1) was obtained for samples of cultivated soils and is likely to be connected with occurrence of fertile soil (chernozem). Moreover, enrichment of soils with Pb and Zn accompanies magnetic susceptibility anomalies in the vicinity of the high roads and in the steelworks area, respectively.
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