Informacja

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

Wyszukujesz frazę "Mössbauer Spectroscopy" wg kryterium: Temat


Wyświetlanie 1-7 z 7
Tytuł:
Próby klasyfikowania chondrytów zwyczajnych przez zastosowanie spektroskopii mössbauerowskiej
Attempts of classification of ordinary chondrites by application of Mössbauer spectroscopy
Autorzy:
Gałązka-Friedman, Jolanta
Woźniak, Marek
Duda, Przemysław
Jakubowska, Martyna
Bogusz, Patrycja
Karwowski, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/1032381.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
Mössbauer spectroscopy
classification of meteorites
ordinary chondrites
Opis:
Mössbauer spectra of equilibrated ordinary chondrites consist of two sextets due to magnetically ordered iron present in metallic phases and troilite and two doublets due to paramagnetic iron present in olivines and pyroxenes. The Mössbauer spectral areas of the different mineralogical phases in meteorites are proportional to the number of iron ions present in olivines, pyroxenes, metallic phase and troilite. This property of Mössbauer spectra was the basis for constructing various methods for the classification of ordinary chondrites. Review of these methods will be presented.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 23-28
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania mössbauerowskie trzech chondrytów zwyczajnych typu H i trzech chondrytów zwyczajnych typu LL – wyznaczanie niepewności powierzchni spektralnych
Mössbauer studies of three ordinary chondrites type H and three ordinary chondrites type LL – uncertainty of the determination of spectral areas
Autorzy:
Jakubowska, Martyna
Buczek, Aleksandra
Gwiździel, Katarzyna
Djellouli, Adam
Nowak, Filip
Woźniak, Marek
Gałązka-Friedman, Jolanta
Karwowski, Łukasz
Duda, Przemysław
Powiązania:
https://bibliotekanauki.pl/articles/1032384.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
Bassikounou
Buzzard Coulee
Kilabo
Mössbauer spectroscopy
NWA 4841
NWA 6287
Zag
ordinary chondrites
Opis:
Mössbauer 57Fe measurements of three ordinary chondrites type H and of three ordinary chondrites type LL were performed at room temperature. The spectral areas were fitted using the “Recoil” program (Lagarec i in. 1998). Fitting was repeated three times which allowed us to determinate the differences between the results of fits performed by different persons.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2019, 10; 34-39
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative Mössbauer studies of the Baszkówka ordinary chondriteand some other meteorites
Autorzy:
Gałązka-Friedman, J.
Bauminger, E. R.
Nowik, I.
Bakun-Czubarow, N.
Stępniewski, M.
Siemiątkowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/2059308.pdf
Data publikacji:
2001
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
ordinary chondrites
parent body
Mössbauer spectroscopy
Q angle
troilite
kamacite
olivine
pyroxene
weathering
oxidation
Opis:
It was suggested that perhaps Mössbauer parameters of troilite could serve as a criterion for an interpretation of the origin of various meteorites. It was found that in three meteorites coming from the same parent body (Baszkówka, Mt. Tazerzait and Songyuan) the angle between the principal axis of the electric field gradient (EFG) and the direction of the magnetic field in troilite is around 60o. Further investigations showed that in some other meteorites, not belonging to this group, this angle is close to 90o.
Źródło:
Geological Quarterly; 2001, 45, 3; 319-326
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Od Baszkówki do Kuźnicy – 27 lat badań mössbauerowskich meteorytów w Polsce
From Baszkówka to Kuźnica – 27 years of Mössbauer studies of meteorites in Poland
Autorzy:
Gałązka-Friedman, Jolanta
Woźniak, Marek
Powiązania:
https://bibliotekanauki.pl/articles/2195003.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
meteorites
ordinary chondrites
Mössbauer spectroscopy
Baszkówka
Morasko
Kuźnica
Mt. Tazerzait
4M method
meteorites classifications
Opis:
The history, how the Mössbauer studies of meteorites began in Poland, was already described in our “Meteorites Odyssey… 20 years have passed”. One late afternoon (it was probably Spring 1995) I [Jolanta Gałązka-Friedman] was sitting in the Nonna Bakun’s office (at Banacha street) and we were talking about planet Mars. Suddenly Mr. Marian Stępniewski jumped to our room saying: We have a new Polish meteorite. It is called Baszkówka. Do you have any suggestion, how could we study this meteorite? Mössbauer spectroscopy – we both answered at the same time. And this is how it started, and it has been continued for the next quarter of a century. The first results of the Mössbauer studies of the Baszkówka meteorite were presented at the ISIAME conference in Johannesburg in 1996. In this paper we present the most important problems related to meteorites, which were investigated by us using Mössbauer spectroscopy. We will, however, show almost no formulas. We will try to explain everything by a method based on plots of Mössbauer spectra. We will try not to boast too much regarding our successes, but to explain also the problems that we were not able to resolve. While investigating the Baszkówka meteorite, we got most fascinated by troilite. We noticed that most of the laboratories determined the Mössbauer parameters of troilite incorrectly. They did not take into account the so-called theta angle, the value of which depends strongly on the number of vacancies and various additives. We thought that the theta angle may show us the parent body of the investigated meteorite. Unfortunately, this hypothesis turned up to be too difficult to defend. Then we studied Morasko meteorite and we discovered, by the comparison with Baszkówka meteorite Mössbauer spectra, and determined – up to now – not identified mineral phases present also in Morasko, such as pyrrhotite, daubréelite, taenite, tetrataenite, antitaenite and cohenite. In 2019 we published in MAPS a paper titled “Application of Mössbauer spectroscopy, multidimensional discriminant analysis and Mahalanobis distance for classification of equilibrated ordinary chondrites” (4M method), in which a new objective method for classification of ordinary chondrites is based on the knowledge of the Mössbauer spectra of the 4 main mineral phases present in the ordinary chondrites of H, L and LL type. Now we are working on the refinement of the 4M method enlarging our collaborative team by various foreign laboratories.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2023, 14; 31-55
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Odróżnianie próbek prawdziwych meteorytów od kamiennych próbek meteorytopodobnych – ważna rola spektroskopii mössbauerowskiej
Distinguishing between real and false meteorite samples – the important role of Mössbauer spectroscopy
Autorzy:
Bogusz, Patrycja
Gałązka-Friedman, Jolanta
Brzózka, Katarzyna
Jakubowska, Martyna
Woźniak, Marek
Karwowski, Łukasz
Duda, Przemysław
Powiązania:
https://bibliotekanauki.pl/articles/2034025.pdf
Data publikacji:
2022-03
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
ordinary chondrites
meteorites
Leoncin
Pu³tusk
Kheneg Ljouâd
Campos Sales
Julin
Mössbauer spectroscopy
4M method
Opis:
Four stony pieces were delivered to our laboratory for checking if they are fragments of meteorites: first sample (sample No. 1) was a fragment of a rock that fell near Leoncin in Poland, second sample (sample No. 2) was a fragment of a rock found also in Poland in the vicinity of Pultusk, third sample (sample No. 3) was a meteorite specimen bought on the meteorite exchange and fourth sample (sample No. 4) was a stone object whose decline was observed in Europe. We obtained mössbauer spectra of the delivered samples. The mössbauer spectrum of sample No. 1 is very similar to the spectrum of ordinary chondrite of type LL. Comparison of the mössbauer spectrum of sample No. 2 with mössbauer spectrum of Pu³tusk meteorite showed very large differences. In the spectrum of sample No. 3, a clear signal from iron-nickel alloy and troilite can be observed. These observations indicate that it is an object of extraterrestrial origin. Mössbauer spectrum of Sample No. 4 is similar to the spectrum of terrestrial magmatic rocks. Based on these spectrum we cannot clearly determine where the examined object comes from. This work demonstrates the usefulness of Mössbauer spectroscopy in recognizing samples that are fragments of meteorites.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2022, 13; 27-36
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metoda 4M – nowe zastosowanie spektroskopii mössbauerowskiej w klasyfikacji zrównoważonych chondrytów zwyczajnych
4M method – the new application of Mössbauer spectroscopy for classification of equilibrated ordinary chondrites
Autorzy:
Woźniak, Marek
Karwowski, Łukasz
Gałązka-Friedman, Jolanta
Duda, Przemysław
Jakubowska, Martyna
Bogusz, Patrycja
Powiązania:
https://bibliotekanauki.pl/articles/1033156.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
4M method
Cluster Analysis
Mahalanobis distance
Multidimensional Discriminant Analysis
Mössbauer spectroscopy
Principal Components Analysis
meteorites
meteorites classification
ordinary chondrites
Opis:
The 4M method aims to determine the type of equilibrated ordinary chondrite only on the basis of the Mössbauer spectrum of the investigated meteorite. Mössbauer spectrum of non-weathered ordinary chondrite is comprised of four sub-spectra: two doublets and two sextets. One of the doublets consists of a signal from iron present in olivine and the other consists of a signal from iron present in pyroxene. Sextets on the other hand, contain signals from magnetically ordered iron. One sextet is related to the metallic phase (kamacite, taenite), whereas the second is related to troilite. A third of doublets, which emerges in weathered ordinary chondrites, is related to products of the oxidation of iron present in metallic phase. The spectral areas of olivine, pyroxenes, metallic phase and troilite, which were obtained from Mössbauer spectrum are proportional to the number of iron atoms present in relevant mineral phases. Some Mössbauer groups were inspired by this fact to construct different methods to determine the type (H, L, or LL) of investigated meteorites (Gałązka-Friedman et al. 2019, Hyp. Inter. 241(1)). However, these methods, based on subjective criteria, were only qualitative. Our group elaborated a quantitative method, which is based on objective criteria. We called it the "4M method" (where M are derived from meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis (MDA), Mahalanobis distance) (Woźniak et al. 2019). This method was using only the Mössbauer experimental data, to which it applied advanced statistical methods. The base, which was created from Mössbauer data, consisted of three clusters H, L, LL. These clusters were constructed with sets of 4-dimensional vectors. The vectors are comprised of spectral areas of Mössbauer spectrum: ol (value proportional to iron present in olivine), pyr (value proportional to iron present in pyroxene), met (value proportional to iron present in metallic phase), tr (value proportional to iron present in troilite). To determine the type of investigated ordinary chondrite, its ol, pyr, met and tr values with average values of variables obtained for clusters H, L and LL need to be compared. The comparison can be performed with the use of MDA and Mahalanobis distance. Once Mahalanobis distance of the investigated meteoriteis is known, the level of similarity to three types of ordinary chondrites can be calculated. Examples of such calculations were performed for seven ordinary chondrites: Goronyo, Carancas, New Concord, NWA 7733, Leoncin, Sołtmany and Pułtusk. They were made with the use of the new base composed of 62 non-weathered ordinary chondrites. All results obtained with the 4M method yielded results consistent with traditional mineralogical methods.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2020, 11; 125-140
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Średni ciężar atomowy chondrytu Vicência (LL3.2)
Mean atomic weight of Vicência LL3.2 chondrite
Autorzy:
Szurgot, Marian
Powiązania:
https://bibliotekanauki.pl/articles/1033113.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Meteorytowe
Tematy:
LL3 chondrites
Mössbauer spectroscopy
Vicência chondrite
grain density
iron to silicon ratio
mean atomic number
mean atomic weight
ordinary chondrites
troilite content
Opis:
Mean atomic weight Amean of Vicência (LL3.2 S1W0, fall 2013) ordinary chondrite has been calculated using literature data (Keil et al. 2015) on chemical composition of the meteorite and using relationships: between mean atomic weight and Fe/Si atomic ratio, between Amean and grain density, and between Amean and magnetic susceptibility. It was shown that Vicência’s Amean = 22.91 for composition without water. This value is close to the mean atomic weight of LL chondrite falls, is close to Amean value of LL3 chondrite falls, and is close to Amean value of Semarkona LL3.0 chondrite. Vicência’s Fe/Si atomic ratio (0.492±0.050) leads to Amean = 23.06–23.26, which is close to the value determined by bulk composition. Vicência’s Fe/Si atomic ratio is close to the value for Semarkona’s (Fe/Si = 0.511), and is close to LL’s mean Fe/Si ratio (0.520). This confirms that Vicência belongs to LL chondrites, as previously classified. Using dependence between mean atomic weight and grain density leads to Amean = 21.89±0.54 (dgr = 3.28 g/cm3, Keil et al. 2015), and using dependence between Amean and magnetic susceptibility gives Amean = 23.01±0.24 (logc = 4.30, Keil et al. 2015). Arithmetic mean of Amean (dgr), Amean (logc), and Amean(Fe/Si), gives 22.72±0.73, the value close to Amean(bulk composition) determined using compositional data. Mean atomic number Zmean, and Amean/Zmean ratio of the meteorite have been also calculated. Vicência’s Zmean = 11.37, and Amean/Zmean ratio is: 2.015 for composition without water. Vicência’s silicates shown the values: Amean = 21,67, Zmean = 10.76, Amean/Z mean = 2.014, Fe/Si = 0.318, Amean(Fe/Si) = 22.07–22.18, and Fe, Ni metal values: Amean = 56.63, Zmean = 26.53, and Amean/Z mean = 2.135. Two dependences: i) grain density dgr on Amean, and ii) grain density dgr on Fe/Si atomic ratio, were used to determine/verify grain density of Vicência chondrite. It was established that dgr(Amean) leads to the values: 3,42 g/cm3 for Vicência chondrite, 3,25 g/cm3 for silicates, and 7,90 g/cm3 for Fe, Ni metal of Vicência meteorite. Dependence dgr(Fe/Si) predicts density for Vicência chondrite: 3,47–3,49 g/cm3, and for silicates: 3,32–3,35 g/cm3.
Źródło:
Acta Societatis Metheoriticae Polonorum; 2018, 9; 126-144
2080-5497
Pojawia się w:
Acta Societatis Metheoriticae Polonorum
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-7 z 7

    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