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Wyświetlanie 1-15 z 17
Tytuł:
Preparation, characterization of a ceria loaded carbon nanotubes nanocomposites photocatalyst and degradation of azo dye Acid Orange 7
Autorzy:
Wen, T.
Tang, Y.-B.
Mo, B.-Y.
Powiązania:
https://bibliotekanauki.pl/articles/204686.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Carbon nanotubes
ceria
nanocomposites photocatalyst
preparation
acid orange 7
Opis:
A ceria loaded carbon nanotubes (CeO2/CNTs) nanocomposites photocatalyst was prepared by chemical precipitation, and the preparation conditions were optimized using an orthogonal experiment method. HR-TEM, XRD, UV-Vis/DRS, TGA and XPS were used to characterize the photocatalyst. Nitrogen adsorption-desorption was employed to determine the BET specifi c surface area. The results indicated that the photocatalyst has no obvious impurities. CeO2 was dispersed on the carbon nanotubes with a good loading effect and high loading effi ciency without agglomeration. The catalyst exhibits a strong ability to absorb light in the ultraviolet region and some ability to absorb light in the visible light region. The CeO2/CNTs nanocomposites photocatalyst was used to degrade azo dye Acid Orange 7 (40 mg/L). The optical decolorization rate was 66.58% after xenon lamp irradiation for 4 h, which is better than that of commercial CeO2 (43.13%). The results suggested that CeO2 loading on CNTs not only enhanced the optical decolorization rate but also accelerated the separation of CeO2/CNTs and water.
Źródło:
Archives of Environmental Protection; 2016, 42, 2; 12-19
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Heat Treatment on Soft Magnetic Properties of the $Fe_{60}Co_{10}Mo_{2}Y_{8}B_{20}$ Alloy
Autorzy:
Garus, S.
Nabiałek, M.
Garus, J.
Powiązania:
https://bibliotekanauki.pl/articles/1375479.pdf
Data publikacji:
2014-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.-y
75.50.Kj
75.30.Ds
75.20.En
75.47.Np
75.50.Bb
75.60.Ej
Opis:
This paper presents the results of studies on the magnetic properties of the $Fe_{60}Co_{10}Mo_{2}Y_{8}B_{20}$ alloy. The samples were fabricated in the form of plates by the injection-casting method. The structure of the investigated alloy, in the as-quenched state and after annealing, was verified by using X-ray diffractometry. The magnetization curves as a function of temperature were measured by a force magnetometer. From thermomagnetic curves the Curie temperature of the alloy was determined. As a critical parameter β was chosen to be equal to 0.36 for these calculations, it confirmed that the alloys may be considered as ferromagnetic of the Heisenberg type. Additionally, using a vibrating sample magnetometer the magnetization and coercivity field were studied (in magnetic field up to 2 T).
Źródło:
Acta Physica Polonica A; 2014, 126, 4; 960-962
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structure and Magnetic Properties of Amorphous $Fe_{60}Co_{10}Mo_{2}W_{x}Y_8 B_{20-x}$ (x=0, 1) Alloys
Autorzy:
Błoch, K.
Nabiałek, M.
Garus, S.
Powiązania:
https://bibliotekanauki.pl/articles/1398365.pdf
Data publikacji:
2016-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Np
75.50.Bb
75.50.Kj
75.90.+w
Opis:
This paper presents studies of the bulk amorphous alloys: $Fe_{60} Co_{10} Mo_2 Y_{8} B_{20}$ and $Fe_{60} Co_{10} Mo_2 W_1 Y_8 B_{19}$; Both compounds were obtained by means of the injection-casting method in which liquid alloy is forced under pressure into a copper mould. The structure of the samples was studied using X-ray diffraction and scanning electron microscopy. Based on the results of the X-ray diffraction studies, it was found that the samples were in the amorphous state. Scanning electron microscopy image analysis of fractured alloy samples indicated the presence of areas of varying degrees of relaxation: "smooth", "vein", and "flake" fractures. The manufactured ferromagnetic samples were characterized by so-called soft magnetic properties with a relatively high Curie temperature of more than 520 K. In the investigated samples, the saturation magnetization was found to have been decreased from 1.14 T to 1.13 T after the addition of W. Tungsten also contributed significantly to an increase in the value of the coercive field, from 27 A/m to 8685 A/m. Following the addition of just 1% of W to the alloy, a substantial change was observed in the form: of the static magnetic hysteresis loop: characterized by the so-called "wasp" shape. This result shows that an additional magnetically hard phase had appeared within the sample.
Źródło:
Acta Physica Polonica A; 2016, 130, 4; 905-908
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetocaloric Properties of Fe₇₅Mo₈Cu₁B₁₆ and Fe₈₁Mo₈Cu₁B₁₀ Metallic Glasses
Autorzy:
Hasiak, M.
Miglierini, M.
Kaleta, J.
Bujdoš, M.
Powiązania:
https://bibliotekanauki.pl/articles/1387599.pdf
Data publikacji:
2015-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Sg
71.23.Cq
76.80.+y
87.64.Pj
Opis:
Microstructure and thermomagnetic properties for the Fe₇₅Mo₈Cu₁B₁₆ and Fe₈₁Mo₈Cu₁B₁₀ metallic glasses in the as-quenched state and after heat treatment at 643 K and 723 K are studied. The inverse change of the Curie point was observed for Fe₇₅Mo₈Cu₁B₁₆ metallic glass after annealing below the onset of crystallization. It is attributed to structural relaxation of the amorphous phase. The maximum of magnetic entropy change calculated for magnetic field of 1.0 T occurs for the Fe₇₅Mo₈Cu₁B₁₆ alloy annealed at 643 K at temperature close to the Curie point and equals 0.74 J kg¯¹ K¯¹.
Źródło:
Acta Physica Polonica A; 2015, 127, 2; 608-610
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fabrication of Mo-Si-B Intermetallic Compound Powders Under Different Heat Treatment Conditions
Autorzy:
Park, J. H.
Lee, S.
Kim, D.
Kim, Y.
Yang, S. H.
Lee, S. H.
Powiązania:
https://bibliotekanauki.pl/articles/353369.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Mo-Si-B alloys
intermetallic compounds
reitveld refinement
T2 phase
A15 phase
Opis:
In this research, we investigated the effects of reduction atmospheres on the creation of the Mo-Si-B intermetallic compounds (IMC) during the heat treatments. For outstanding anti-oxidation and elevated mechanical strength at the ultrahigh temperature, we fabricated the uniformly dispersed IMC powders such as Mo5SiB2 (T2) and Mo3Si (A15) phases using the two steps of chemical reactions. Especially, in the second procedure, we studied the influence of the atmospheres (e.g. vacuum, argon, and hydrogen) on the synthesis of IMCs during the reduction. Furthermore, the newly produced IMCs were observed by SEM, XRD, and EDS to identify the phase of the compounds. We also calculated an amount of IMCs in the reduced powders depending on the atmosphere using the Reitveld refinement method. Consequently, it is found that hydrogen atmosphere was suitable for fabrication of IMC without other IMC phases.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 3; 1509-1512
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Ion Irradiated Fe₇₅Mo₈Cu₁B₁₆ Metallic Glass
Autorzy:
Hasiak, M.
Miglierini, M.
Powiązania:
https://bibliotekanauki.pl/articles/1032745.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Kj
75.60.Ej
75.30.Sg
76.80.+y
Opis:
Microstructure and thermomagnetic properties of ion-bombarded amorphous Fe₇₅Mo₈Cu₁B₁₆ alloy are investigated. The Mössbauer spectroscopy shows that surface regions at the air side of the ribbons irradiated with 2×10¹⁶ ions/cm² were significantly affected by 130 keV N⁺ ions. On the other hand, the opposite (wheel) side that was not exposed to ion irradiation is practically intact. The analysis of temperature dependences of magnetization shows the Curie points of 313 K and 316 K for as-quenched and irradiated samples, respectively. The maximum of magnetic entropy change calculated for the irradiated alloy in a magnetic field of 1.0 T occurs at 312.5 K and equals to 0.77 J kg¯¹ K¯¹ while that of the as-quenched sample is 0.74 J kg¯¹ K¯¹.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 768-770
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructure and magnetic properties of the classical amorphous alloys: Fe₆₁Co₁₀Y₈Me₁B₂₀ (where Me = W, Mo)
Autorzy:
Pietrusiewicz, P.
Nabiałek, M.
Powiązania:
https://bibliotekanauki.pl/articles/1113170.pdf
Data publikacji:
2016-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Kj
75.50.Bb
75.50.Lk
75.50.-y
61.43.Dq
61.43.-j
68.37.Hk
75.70.Ak
Opis:
A study has been conducted into the effects of substituting small quantities of alloying elements (tungsten and molybdenum) on the structure and magnetic properties of classical amorphous alloys that are based on the formula: Fe₆₁Co₁₀Y₈Me₁B₂₀. The structure of the resulting alloy samples was examined using X-ray diffraction, Mössbauer spectroscopy, and scanning electron microscopy. Based on the results of these studies, it was found that the obtained alloys were amorphous. Images from the scanning electron microscope were typical for amorphous materials. Cross-sectional images were homogeneous and did not contain "vein- and scale-type" precipitations. Studies examining the magnetic properties of the samples were carried out using a vibrating sample magnetometer. It was found that the alloy featuring the addition of tungsten exhibited a significantly greater saturation of magnetization and a substantially lower coercivity. This resulted from the fact that the atomic radius of tungsten is much larger than that of molybdenum, resulting in increased difference between the atomic constituents of the alloy; This, in turn, improves the glass-forming ability.
Źródło:
Acta Physica Polonica A; 2016, 130, 4; 920-922
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of Ion-Irradiation upon Microstructure and Magnetic Properties of NANOPERM-Type Fe₈₁Mo₈Cu₁B₁₀ Metallic Glass
Autorzy:
Hasiak, M.
Miglierini, M.
Powiązania:
https://bibliotekanauki.pl/articles/1030756.pdf
Data publikacji:
2018-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Bb
75.60.Ej
75.30.Kz
61.80.-x
76.80.+y
Opis:
Microstructure and soft magnetic properties of the Fe₈₁Mo₈Cu₁B₁₀ amorphous alloy in the as-quenched state and after irradiation with N⁺ ions are investigated. CEMS spectra show that the irradiated surface at the air side of the ribbons was significantly affected. On the other hand, no noticeable changes were observed at the opposite wheel side. More deep subsurface regions are also not altered as evidenced by CXMS spectra. Thermomagnetic measurements have shown presence of two magnetically different phases with well distinguished Curie points. They can be ascribed to the amorphous matrix and crystalline phases. The latter were quenched-in during the production process and/or induced by ion bombardment. Curie temperatures of the amorphous matrixes were calculated using the Heisenberg model. For the as-quenched and irradiated ribbons they are of 223 K and 228 K, respectively. The behaviour of coercivity versus temperature was also analysed.
Źródło:
Acta Physica Polonica A; 2018, 133, 3; 680-683
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Thermal and Magnetic Properties of Amorphous Ribbons of Fe₆₁Co₁₀B₂₀Y₈Me₁ (where Me = W, Zr, Nb, Mo)
Autorzy:
Pietrusiewicz, P.
Nabiałek, M.
Powiązania:
https://bibliotekanauki.pl/articles/1032157.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.Dq
75.50.Kj
65.60.+a
75.30.Gw
Opis:
This paper presents the results pertaining to thermal and magnetic studies of rapidly-cooled samples of the alloy family Fe₆₁Co₁₀B₂₀Y₈Me₁ (where Me = Nb, Zr, W, Mo). The resulting ribbons, or tapes, have amorphous structure. It has been found that the addition of Me elements alters the thermal and magnetic properties. It is noted that the saturation magnetization decreases with increasing number of unpaired electrons on the valence shells. In addition, the value of the coercivity and effective anisotropy have been determined.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 678-680
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Cobalt Substitution on Hyperfine Interactions in $(Fe_{1-x}Co_x)_{76}Mo_8Cu_1B_{15}$ Alloys
Autorzy:
Kaňčuch, T.
Miglierini, M.
Lancok, A.
Švec, P.
Illeková, E.
Powiązania:
https://bibliotekanauki.pl/articles/1813526.pdf
Data publikacji:
2008-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.46.-w
75.75.+a
76.80.+y
Opis:
The effect of cobalt substitution on structure, magnetic behaviour, magnetic arrangement, and hyperfine interactions in $(Fe_{1-x}Co_x)_{76}Mo_8Cu_1B_{15}$ (x = 0, 0.1, 0.2, 0.25, 0.5) is studied by the Mössbauer spectrometry for both as-quenched and annealed alloys. Partial substitution of Fe by Co resulted in an enhancement of the average value of hyperfine magnetic field distributions as a function of x probably due to higher magnetic moment of Co. After annealing, a two-phase nanocrystalline structure composed of amorphous matrix and bcc-FeCo nanocrystallites was observed. Mössbauer spectra were fitted with up to four six-line patterns of narrow lines assigned to different number of Co nearest neighbours inside a bcc-FeCo lattice.
Źródło:
Acta Physica Polonica A; 2008, 113, 1; 63-66
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural, Chemical Bonding, Electronic and Magnetic Properties of $XY_{3}$ (X = Al, Ga and Y = V, Nb, Cr, Mo) Compounds
Autorzy:
Hafeez, R.
Murtaza, G.
Khenata, R.
Wong, Kin
Naeem, S.
Khalid, M.
Alahmed, Z.
Bin Omran, S.
Powiązania:
https://bibliotekanauki.pl/articles/1398966.pdf
Data publikacji:
2015-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.15.Ap
71.20.-b
Opis:
The metallic behavior of the band gap of intermetallic compounds has large applications in superconductivity, nickel-metal hydrides batteries, semiconductors, and heating materials. The presence of transition elements makes them more attractive for magnetic applications. In this work we studied the structural, electronic, chemical bonding, and magnetic properties of binary intermetallic compounds $XY_3$ (X = Al, Ga and Y = V, Nb, Cr, Mo). These compounds were investigated by using full potential linearized augmented plane wave plus local orbitals method. The exchange correlation potential of generalized gradient is used. Our calculated lattice constants are in good agreement with experimental values. The band structures of these compounds are purely overlapping across the Fermi level. The bonding is mainly covalent in these compounds. The density of states of the compounds shows that the major contribution arises from d-states of anions. The investigation carried out shows that the most of these compounds have ferromagnetic nature, while few are diamagnetic. On the basis of this study it is expected that these compounds can be used as a best moulds for future study on similar compounds.
Źródło:
Acta Physica Polonica A; 2015, 127, 3; 770-779
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influences of Production Method and Minor Chemical Composition Changes on the Microstructure of the Alloy: $Fe_{62-x} Co_{10} Y_8 Mo_x B_{20}$ (where x=1 or 2)
Autorzy:
Nabiałek, M.
Garus, S.
Powiązania:
https://bibliotekanauki.pl/articles/1398367.pdf
Data publikacji:
2016-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.-y
75.50.Kj
75.30.Ds
75.20.En
75.47.Np
75.50.Bb
75.60.Ej
Opis:
In this work, the results of studies concerning the structure of polycrystalline and amorphous alloys are presented. The samples were produced in a single-step production process, using two different production methods, and under a protective argon atmosphere. The quenching speed of the molten alloy was different for each of the production methods. Samples were subjected to analysis using X-ray diffractometry, scanning electron microscopy, and computer tomography. It has been shown that the samples manufactured with a higher cooling rate feature an amorphous structure; On the other hand, the samples obtained using the method with the lower cooling speed consist of crystallites of three crystalline phases with sizes of the order of μm. The amorphous samples exhibited a varied fracture surface as well as an increase in the contribution of pores to their volume, in comparison to the samples obtained at the lower cooling speed.
Źródło:
Acta Physica Polonica A; 2016, 130, 4; 1010-1012
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Selected Alloying Elements on the Soft-Magnetic and Mechanical Properties of Injection-Cast Fe61Co10Y8Me1B20 Alloys (Me = Nb, W or Mo)
Autorzy:
Pietrusiewicz, P.
Nabiałek, M.
Powiązania:
https://bibliotekanauki.pl/articles/356969.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnetic properties
mechanical properties
abrasion resistance
microhardness
Curie temperature
Opis:
Properties of amorphous alloys differ from each other when they are produced at different cooling rates and from different chemical compositions. This paper presents studies of the magnetic and mechanical properties of Fe61Co10 Y8 Nb1 B20, Fe61 Co10 Y8 -W1 B20 and Fe61 Co10 Y8 Mo1 B20 alloys, in the form of plates, produced by the injection of liquid alloy into a copper mould. Based on the performed studies, it was found that the substitution of 1% non-magnetic additive into the alloy composition had little effect, as regards the values of saturation magnetization (Ms ) and Curie temperature (Tc ). However, in the case of the coercive field, the sample with the W addition had a value almost half that of the other two alloys. For all of the studied alloys, the microhardness was about 1180 μHv100, i.e. significantly higher than for the same materials in the crystalline state.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 1; 61-64
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbon Co-Deposition During Gas Reduction of Water-Atomized Fe-Cr-Mo Powder
Autorzy:
Ali, B.
Choi, S. H.
Seo, S. J.
Maeng, D. Y.
Lee, C. G.
Kim, T. S.
Park, K. T.
Powiązania:
https://bibliotekanauki.pl/articles/352709.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
water atomization
Fe-based powder
oxide reduction
powder metallurgy
sinter-hardening alloys
Opis:
The water atomization of iron powder with a composition of Fe-3Cr-0.5Mo (wt.%) at 1600°C and 150 bar creates an oxide layer, which in this study was reduced using a mixture of methane (CH4) and argon (Ar) gas. The lowest oxygen content was achieved with a 100 cc/min flow rate of CH4, but this also resulted in a co-deposition of carbon due to the cracking of CH4. This carbon can be used directly to create high-quality, sinter hardenable steel, thereby eliminating the need for an additional mixing step prior to sintering. An exponential relationship was found to exist between the CH4 gas flow rate and carbon content of the powder, meaning that its composition can be easily controlled to suit a variety of different applications.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 2B; 1119-1124
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature behaviour of hyperfine magnetic fields in a Fe-Co-Si-B-Mo-P metallic glass followed with ⁵⁷Fe Mössbauer spectrometry
Autorzy:
Cesnek, M.
Miglierini, M.
Kmječ, T.
Kohout, T.
Amini, N.
Janičkovič, D.
Matúš, P.
Powiązania:
https://bibliotekanauki.pl/articles/1053048.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Kj
75.60.Ej
75.75.-c
76.80.+y
Opis:
Amorphous glass with nominal chemical composition Fe₅₁Co₁₂Si₁₆B₈Mo₅P₈ was studied by combination of the Mössbauer spectroscopy and magnetic measurements in order to characterize magnetic and structural features. Temperature evolution of the Mössbauer spectra revealed presence of broad distribution of hyperfine magnetic field at lower temperatures which vanishes with increase of temperature. The Curie temperature estimated from the Mössbauer spectroscopy experiments is T_{C} ≈ 392 K. This value is in a good agreement with that obtained by magnetic measurements (T_{C}=397 K). The Mössbauer spectroscopy spectra of the sample annealed at 823 K revealed a presence of crystalline components. This temperature is notably lower than the expected temperature of the onset of crystallization observed by differential scanning calorimetry ( ≈ 835 K).
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 744-746
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 17

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