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1

Multi-stage fault formation and REE distribution in the surrounding Devonian dolomites in the south-eastern part of the Holy Cross Mountains (Poland)

Nieć Marek, Pawlikowski Maciej, Sermet Edyta

Geology, Geophysics and Environment

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2024

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Vol. 50, no. 1

77--92

EN

Metallogenic studies carried out in the Holy Cross Mountains indicate a relationship between mineralization and fault tectonics in Devonian formations. The impact of fault formation on the geochemistry of host rocks has not yet been studied. Mineralogical and geochemical studies of fault core gouges and damage zones in the fault walls of Devonian dolomites in the Budy and Jurkowice quarries were carried out. In the clay-carbonate filling of the fault fissure, the presence of two generations of Fe sulfides, the increased content of Zr, Nb, U and Th in relation to the surrounding rocks was noted. In the fault walls of the dolomites, iron sulfide and hematite mineralization were found. Research on the REE content indicates that it is lower in the fault walls than in those located far from it, while it is clearly higher in the fault gouge, especially in terms of the content of “heavy” elements (HREE). This indicates both the supply of some components to the fault zone from external sources and their displacement from the surrounding rocks. It was also found that the fault was renewed before and after the Neogene at least twice (Badenian).

2

Metale ziem rzadkich : otrzymywanie i odzysk z materiałów odpadowych

Saternus M., Willner J., Fornalczyk A., Lisińska M.

Przemysł Chemiczny

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2017

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T. 96, nr 7

1595--1599

PL

Metale ziem rzadkich zyskują coraz większe znaczenie we współczesnym świecie. Stosowane są do produkcji magnesów, laserów, szkła, luminoforów. Lampy LED, komputery czy telewizory to urządzenia, które bez tych metali nie mogłyby istnieć. Przedstawiono podstawowe zastosowanie metali ziem rzadkich. Podano ceny ich tlenków w latach 1995-2016 oraz wielkość ich produkcji. Przedstawiono metody produkcji tych metali z rud oraz ich alternatywne otrzymywanie poprzez recykling materiałów odpadowych, takich jak magnesy, fosfory czy akumulatory NiMH. W podsumowaniu podano prognozę zużycia metali ziem rzadkich.

EN

A review with 55 refs.

3

Production of rare earths ion beams in arc discharge ion source using their oxides

Turek M., Droździel A., Pyszniak K., Prucnal S.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 8

158--161

EN

Production of rare earth’s ions from using their oxides and carbon tetrachloride (CCl4) vapor is described. Mechanism of internal chemical synthesis of rare earth’s chlorides is proposed. Working characteristics like dependences of ion currents on discharge and filament current, magnetic flux density as well as CCl4 flux are presented and discussed in order to find optimal working parameters. The separated currents of 18 A, 5 A, 3 A and 12 A were obtained for Eu+, Gd+, Ho+ and Pr+, respectively.

PL

W atykule opisana jest metoda wytwarzania wiązek jonów pierwiastków ziem rzadkich wykorzystująca ich tlenki i pary czterochlorku węgla (CCl4). Zaproponowano także wyjaśnienie mechanizmu wewnętrznej syntezy chlorków ziem rzadkich. Celem znalezienia optymalnych parametrów pracy rozpatrywanane są charakterystyki robocze źródła, takie jak zależności natężenia prądów jonowych od natężeń prądu wyładowania, grzania katody, indukcji magnetycznej zewnętrznego magnesu jak również nacieku CCl4. Otrzymano rozseparowane wiązki jonów Eu+, Gd+, Ho+ i Pr+ o natężeniach odpowiednio 18 A, 5 A, 3 A i 12 A.

4

Conventional synthesis and characterization of rare earth doped barium borophosphates, BaBPO5:RE (Y, Gd and La)

Çelik Gül G., Kurtuluş F.

Archives of Materials Science and Engineering

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2016

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Vol. 81, nr 2

49--54

EN

Purpose: of this research, our target is synthesis and characterization of rare earth metals such as Y, Gd and La doped barium borophosphate compounds which are applicable in non-linear optics industry. Design/methodology/approach: The starting materials rare earth oxides, barium carbonate, boric acid and ammonium dihydrogen phosphate as analytically grade weighed 0.01:1:1:1 molar ratio and homogenized in an agate mortar. The mixture placed into a porcelain crucible to heat in high temperature oven step by step. First, mixtures were waited at 400°C for 2 hours for calcination process, subsequently heated 900°C with step rate 10°C/m for 8 hours, and finally cooled down to room temperature with step rate 10°C/m. After many grindings final product get ready for characterization. X-ray powder diffraction (XRD) analysis was performed using PANanalytical X’Pert PRO Diffractometer (XRD) with Cu Kα (1.5406 Å, 45 kV and 30 mA) radiation. Fourier transform infrared spectroscopy (FTIR) was taken on a Perkin Elmer Spectrum 100 FTIR Spectrometer from 4000 to 650 cm-1. Scanning electron microscopy was achieved in SEM JEOL 6390-LV. Luminescence properties were performed by Andor Solis Sr 500i spectrophotometer. Conventional solid state syntheses were done in Protherm furnace. Findings: The powder XRD patterns of the samples show that there is no impurity related to doping materials mean all diffractions corresponding to host material barium borophosphate crystallized in hexagonal system with unit cell parameters a=7.1003 and c=6.9705 Å. The unit cell parameters of rare earth doped barium borophosphates were calculated and display both increase and decrease depends on ionic Radius of rare earths. The other supporting methods confirm the crystal structure and luminescence properties. Research limitations/implications: The synthesis method has some disadvantages such as low homogeneity, non-uniform product etc. We tried to minimize these negative aspects in our research and succeeded. Practical implications: Phosphor materials Y:BaBPO5, Gd:BaBPO5 and La:BaBPO5 (ICSD 51171) were synthesized by conventional solid state method and characterizations was mainly based on powder X-ray diffraction pattern. Also, morphological and luminescence properties were completed to get the highest knowledge. Originality/value: Of the paper is first time conventional synthesis of Y, Gd and La doped BaBPO5 compounds, calculation of unit cell parameters, and investigation of morphological and luminescent properties.

5

Wzrost monokryształów molibdenianu wapnia domieszkowanych jonami ziem rzadkich (CaMoO4 : RE) do badań w zakresie immobilizacji odpadów radioaktywnych

Świrkowicz M., Szyrski W., Kisielewski J., Wieteska K., Wierzchowski W., Malinowska A., Wierzbicka E., Karaś A., Jurkiewicz-Wegner E.

Materiały Elektroniczne

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2013

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T. 41, nr 4

10--19

PL

Stosując metodę Czochralskiego oraz układ cieplny z tyglem platynowym o średnicy 55 mm i wysokości 55 mm oraz biernym dogrzewaczem platynowym uzyskano monokryształy CaMoO4 niedomieszkowane i domieszkowane europem, neodymem oraz jednocześnie europem i neodymem o średnicy do 25 mm i długości do 90 mm. Szybkość wzrostu zawarta była w zakresie 1,5 - 3,0 mm/h, a szybkość obrotowa 10 - 15 obr./min. Pierwsze procesy wzrostu przeprowadzono stosując niezorientowane zarodki z CaWO4 (National Institute of Standards and Technology, USA). W oparciu o otrzymane monokryształy przygotowano zarodki o orientacji [001]. Przeprowadzono badania dyfrakcyjne rentgenowskie, synchrotronowe topograficzne, właściwości optycznych i składu chemicznego. Określono współczynniki segregacji europu i neodymu (kEu ≈ 0,40, kNd ≈ 0,28). Stwierdzono, że w przypadku współdomieszkowania rośnie współczynnik segregacji neodymu a maleje europu (kEu ≈ 0,30 i kNd ≈ 0,32). Transmisja optyczna monokryształów silnie zależy od domieszki. W przypadku neodymu obserwuje się wyraźne i ostre pasma absorpcji. Monokryształy z europem wykazują silną absorpcję w zakresie widzialnym i bliskiej podczerwieni.

EN

Single crystals of CaMoO4 either undoped or doped with europium, neodymium and europium and at the same time with neodymium with a diameter of 25 mm and a length of up to 90 mm, were obtained using the Czochralski method and a thermal system with a platinum crucible 55 mm in diameter and 55 mm in height and a passive platinum afterheater. The growth rate was in the 1.5 - 3.0 mm/h range and the rotation rate varied between 10 and 15 r./min. At the beginning, the growth processes were carried out applying un-oriented CaWO4 seeds (from the National Institute of Standards and Technology, USA). Based on the resultant single crystals, [001] - oriented seeds were prepared. X-ray powder diffraction patterns, synchrotron topography, optical transmission and chemical compositions were measured. Segregation coefficients of europium and neodymium were determined to be kEu ≈ 0,40 and kNd ≈ 0,28 respectively. In the case of co-doping, the segregation coefficient of neodymium increases and that of europium decreases (kEu ≈ 0,30 and kNd ≈ 0,32). The optical transmission of single crystals strongly depends on the dopant. Sharp and narrow absorption bands are observed for neodymium, whereas single crystals with europium exhibit a strong absorption in the visible and near-infrared regions.

6

Influence of heavy metal oxide and activator concentration on spectroscopic properties of Eu3+, Dy3+ and Tb3+ ions in lead borate glasses

Zur L., Pisarska J., Pisarski W. A.

Optica Applicata

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2012

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Vol. 42, nr 2

345-352

EN

Heavy metal lead borate glasses doped with rare earth ions were examined. The influence of heavy metal oxide PbO and activator concentration on luminescence properties of rare earth ions are discussed. Rare earth ions were limited to Eu3+, Dy3+ and Tb3+ which are emitting in the visible light. Increasing concentration of lead oxide in relation to boron oxide causes an increase in R (Eu3+), Y/B (Dy3+) and G/B (Tb3+) spectroscopic factors which correspond to the relative integrated luminescence intensities of 5D0-7F2/5D0-7F1, 4F9/2-6H13/2/4F9/2-6H15/2 and 5D4-7F5/5D4-7F6 transitions, respectively. Moreover, the influence of heavy metal oxide and activator concentration on luminescence decays from excited states of rare earth ions was examined in details.

7

Effect of lanthanum on the tensile properties of carbon-fibre reinforced thermoplastic polyimide composites

Li J., Cheng X. H.

Materials Science Poland

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2007

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Vol. 25, No. 1

85--93

EN

Rare earth (RE) La modification and air-oxidation methods were used to improve the interfacial adhesion of the carbon fibre reinforced polyimide (CF/PI) composite. The interfacial characteristics of composites reinforced by carbon fibres, treated with different surface modification methods, were investigated comparatively. Results showed that both RE modification and air-oxidation method improved the adhesion between the reinforcement and matrix, and that the RE modification method was superior to the air-oxidation method. For the CF/PI composite, optimum interfacial adhesion was obtained at 0.3 wt. % of La concentration. The fracture surfaces of samples were investigated by scanning electronic microscopy (SEM) to analyse the effects of various surface treatment methods.

8

Preparation and upconversion properties of Er3+,Yb3+:Y2Si2O7 nanocrystallites embedded in PVA polymer nanocomposites

Hreniak D., Głuchowski P., Stręk W., Bettinelli M., Kozłowska A., Kozłowski M.

Materials Science Poland

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2006

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Vol. 24, No. 2/1

405--413

EN

The preparation of polymer nanocomposites consisting of poly(vinyl) alcohol (PVA) network and RE3+:Y2Si2O7 nanocrystalline particles (RE=Yb, Er) is presented. The optical properties of the nanocomposite were preliminarily studied. In particular, efficient upconversion was observed in Er3+ and Yb3+ codoped Y2Si2O7 nanoparticles embedded in the polymeric PVA host. It was found that the luminescence features of the RE3+:Y2Si2O7 nanoparticles were affected by the polymeric host, resulting in a shortening of the luminescence lifetimes. This effect is discussed in terms of effective refractive index.

9

The theory of phase formation in rare earth metal systems

Gschneidner K. A.

Archives of Metallurgy and Materials

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2006

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Vol. 51, iss. 4

519-524

EN

The seventeen elements, which make up the rare earth family, consist of two non-4f - electron members, Sc and Y, and the fifteen 4 f electron containing lanthanide elements including La that has an empty localized 4f shell. In general, the physical properties, such as the metallic radii, electronegativities, melting points, and crystal structure sequence of the metallic elements, vary in a smooth and regular manner. By utilizing these systematic behaviors, we have learned a great deal about the chemical, metallurgical and physical behaviors of not only the rare earth elements, but also the other elements in the Periodic Table. This includes: (1) the dependence of the entropies of transformation and fusion of the pure metals on the structure and electronic nature; (2) the influence of lattice rigidity on solid solution formation and thus solved one of the oldest metallurgical riddles; (3) the representation of 91 binary rare earth diagrams by a single generalize phase diagram; and (4) the existence of 4f bonding in the lanthanide metals, alloys and compounds well before theorists confirmed this by first principle calculations.

PL

Na rodzine siedemnastu pierwiastków ziem rzadkich składają się dwa pierwiastki nie zawierające elektronów 4 f – Sc i Y, i piętnaście lantanowców w tym La, który posiada pustą zlokalizowaną podpowłokę 4 f . Można ogólnie stwierdzić, że własciwości tych metalicznych pierwiastków, takie jak promienie atomowe poszczególnych metali, elektroujemność, temperatury topnienia oraz sekwencja ich strukturkrystalicznych zmieniają się w sposób ciągły i regularny. Korzystając z tych systematycznych zachowań, poznano wiele właściwości chemicznych, metalurgicznych i fizycznych, nie tylko pierwiastków ziem rzadkich, lecz także innych pierwiastków układu okresowego. Dotyczy to w szczególności: (1) zależności entropii transformacji i entropii topnienia czystych metali od ich struktury krystalicznej i elektronowej, (2) wpływu rodzaju sieci krystalicznej na tworzenie roztworów stałych, które pozwala rozwiązać jedną z najstarszych metalurgicznych niejasności, (3) możliwości przedstawienia 91 wykresów pierwiastków ziem rzadkich za pomocą jednego ogólnego wykresu fazowego, (4) występowania wiązań 4 f w lantanowcach, ich stopach i związkach potwierdzonych następnie za pomocą teoretycznych obliczen ab initio.

10

Rare earths complexes in sol gel glasses

Reisfeld R.

Materials Science

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2002

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Vol. 20, No. 2

5--18

EN

The origin of the spectra of rare earth ions arising from f->f and f->d transitions are surveyed. The parity forbidden luminescence of lanthanide ions can be strongly intensified by excitation via molecules characterized by high transition probabilities. Such behavior opens a route for creation of a class of new sophisticated materials. Luminescent materials based on heteroaromatic lanthanide cryptates are attractive as labels for advanced time-resolved fluoroimmunoassays, and molecular markers, their potential use is also conceivable in the field of luminescent displays, molecular photonics and highly luminescent materials in hybrid organic/inorganic glasses. The recent findings of lanthanide complexes trapped in sol-gel inorganic glasses based on silica and zirconia networks are discussed and the theoretical basis of their spectroscopy presented.

11

Physico-Chemical Characteristic of Sulfated Mixed Oxides of Sn with Some Rare Earth Elements

Jyothi T., Sreekumar K., Talawar M., Mirajkar S., Rao B., Sugunan S.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 6

801-812

EN

A series of binary mixed oxides of tin with three rare earth elements viz. La, Ce and Sm were prepared by co-precipitation method and sulfate treatment was performed by treating the mixed hydroxides with sulfuric acid or ammonium sulfate. The physicochemical characterization has been done by XRD, BET-S.A., SEM, EDX, TG-DTA and IR spectroscopy. Adsorption of n-butylamine was used to probe the acidic properties of the catalysts. The strength and distribution of acid sites depend on the mixed metal oxide composition, as well as on the preparation method. The rare earth modified sulfated tin oxide catalysts are more active in the oxidative dehydrogenation of cyclohexanol and cyclohexane, compared to the corresponding mixed oxide systems and sulfated tin oxide. Among the different sulfated oxide systems investigated , cerium prooted catalysts displayed a better selectivity towards dehydrogenation products.