Informacja

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

Wyszukujesz frazę "75.30.Kz" wg kryterium: Temat


Tytuł:
Magnetic Properties and Magnetocaloric Effect οf $R_{1-x}R_{x}Mn_{2}Ge_{2}$ Compounds
Autorzy:
Duraj, M.
Szytuła, A.
Powiązania:
https://bibliotekanauki.pl/articles/1538438.pdf
Data publikacji:
2010-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Kz
75.30.Sg
Opis:
The magnetic and magnetocaloric properties of $Sm_{1-x}Gd_{x}Mn_{2}Ge_{2}$ compounds with 0 ≤ x ≤ 0.10 have been studied. $SmMn_{2}Ge_{2}$ is antiferromagnetic below the Néel temperature $T_{N}$ ( ≈ 400 K). Further cooling leeds to canted ferromagnetic phase below $T_C$ = 341 K. With decreasing temperature, two metamagnetic phase transitions are observed: F2-AF1 at $T_2$ = 153 K and AF1-F1 at $T_1$ = 106 K. The maximum values of magnetic entropy change | Δ $S_m$ | are found to be 1.5 J $K^{-1} kg^{-1}$ at $T_{1}$ and 2.0 J $K^{-1} kg^{-1}$ at $T_{2}$ in $SmMn_{2}Ge_{2}$. The MCE is found to increase with Gd concentration, | Δ $S_{m}(T_{1})$ | = 3.3 J $K^{-1} kg^{-1}$, while | Δ $S_{m}(T_{2})$ | is slightly enhanced for x = 0.1. The magnetocaloric effect is found to be positive at $T_{1}$ and negative at $T_{2}$.
Źródło:
Acta Physica Polonica A; 2010, 117, 4; 603-606
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetocaloric Effect and Transition Order in $HoAl_{2}$
Autorzy:
Baran, S.
Duraj, R.
Szytuła, A.
Powiązania:
https://bibliotekanauki.pl/articles/1399261.pdf
Data publikacji:
2015-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Cr
75.30.Kz
75.30.Sg
Opis:
Magnetic measurements of $HoAl_{2}$ are reported. The compound crystallizes in the cubic $MgCu_{2}$-type crystal structure. $HoAl_{2}$ exhibits two successive magnetic transitions: below $T_{c}$ = 29 K a ferromagnetic order is formed while anomaly at $T_{t}$ = 20 K is related to reorientation of magnetic moment. Near transition temperatures a magnetocaloric effect with magnetic entropy changes -$ΔS_{m}$ equal to 6.3 J/(mol K) at $T_{c}$ and 5.0 J/(mol K) at $T_{t}$ for an external field $μ_{0}H$ = 9 T is observed.
Źródło:
Acta Physica Polonica A; 2015, 127, 3; 815-817
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Power Losses in $LaFe_{x}Co_{y}Si_{1.1}$ Intermetallics near the Magnetic Phase Transition
Autorzy:
Gozdur, R.
Lebioda, M.
Bernacki, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/1402334.pdf
Data publikacji:
2015-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Sg
75.30.Kz
75.50.Bb
Opis:
The paper presents magnetic parameters of $LaFe_{x}Co_{y}Si_{1.1}$ bulk specimens proving strong magnetocaloric effect. The main research work was oriented on measurements of the alloy's power losses according to IEC 60404 standards and validated with unbalanced bridge method and other methods. The measurements of the $LaFe_{10.8}Co_{1.1}Si_{1.1}$ specimens were determined in the range of temperatures near the Curie temperature where the magnetocaloric effect is the strongest. Power losses were taken into account mainly for the evaluation of usefulness and efficiency in the magnetic refrigeration applications. The results of presented measurements testify that the most suitable range of temperature and the best operational conditions are very close to the point of magnetic phase transition and slightly above it. It indicates that the magnetic state between the $T_{ \Delta S max}$ and $T_{c}$ is more effective for the magnetic refrigeration applications due to lower power losses and high level of the isothermal changes of entropy. Operating temperature below the $T_{ \Delta S max}$ in ferromagnetic state is improper because of the increasing power losses which achieve the level of 130 mJ/kg for main frequency and decrease to 20 mJ/kg for the value of 0.1 Hz.
Źródło:
Acta Physica Polonica A; 2015, 128, 1; 98-103
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic properties and flux distribution in the LaFeCoSi/FeCoV hybrid structure
Autorzy:
Gozdur, R.
Lebioda, M.
Najgebauer, M.
Powiązania:
https://bibliotekanauki.pl/articles/1055094.pdf
Data publikacji:
2017-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Sg
75.30.Kz
75.50.Bb
Opis:
The study contains a description of magnetic properties of LaFeCoSi/FeCoV structure. The hybrid structure contains magnetocaloric LaFeCoSi core with high-induction ferromagnetic laminations. The magnetic field inside the magnetic structure is gained by the fringe field from FeCoV laminations. Results of modelling and experimental investigations of modified magnetic properties of LaFeCoSi/FeCoV structure were presented and discussed in the paper.
Źródło:
Acta Physica Polonica A; 2017, 131, 5; 1294-1297
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Field Induced Unusual Magnetic Behavior at Low Temperature in $Pr_{0.67}Ca_{0.33}MnO_3$
Autorzy:
Pektas, M.
Gencer, H.
Izgi, T.
Kolat, V.
Atalay, S.
Powiązania:
https://bibliotekanauki.pl/articles/1207723.pdf
Data publikacji:
2014-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Lx
75.30.Kz
75.30.Sg
Opis:
In this study, magnetic properties of $Pr_{0.67}Ca_{0.33}MnO_3$ compound were investigated in detail. The magnetization versus temperature (M-T) curve showed that this material undergoes a charge order transition at 200 K. A more pronounced FM phase appeared below 56 K. At T = 5 K, a field induced sharp step like magnetisation transition associated with phase separation was observed. However, after application of 7 T magnetic field at 5 K, the magnetic behaviour of sample was changed completely and full FM behaviour was observed. The more interesting is that the sample remains in the FM state and does not retrieve the initial magnetic state until warmed up to charge order transition temperature. Large negative magnetic entropy change (- 26.18 J/(kg K) at 38 K and 5 T) was attributed to step like magnetisation transition.
Źródło:
Acta Physica Polonica A; 2014, 125, 2; 217-219
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetocaloric Effect in Materials with the First Order Transitions - Direct Measurements
Autorzy:
Kamarád, J.
Kaštil, J.
Arnold, Z.
Javorský, P.
Sechovský, V.
Powiązania:
https://bibliotekanauki.pl/articles/1535138.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Sg
75.30.Kz
75.50.Cc
Opis:
The results of direct measurements of the magneto-caloric characteristics Δ $T_{ad}$ and the indirect determination of Δ $S_{m}$ of pure Gd around the Curie temperature and of the $FeMnP_{0.45}As_{0.55}$ and $Ni_{45}Co_5Mn_{31}Ga_{19}$ intermetallics in the vicinity of the first order magnetic and structural phase transitions are presented and discussed. A pronounced temperature and field dependence of the first order transitions in the studied materials manifests restrictions applying these materials in magnetic refrigeration techniques. An effective use of the Ericsson and the Brayton refrigeration cycles with $FeMnP_{0.45}As_{0.55}$ in the role of a refrigerant is discussed.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 1000-1001
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charge-Ordering and Magnetoelastic Coupling Effects on the Magnetocaloric Properties of Manganites
Autorzy:
Reis, M. S.
Gomes, A. M.
Araújo, J. P.
Tavares, P. B.
Amaral, J. S.
Oliveira, I. S.
Amaral, V. S.
Powiązania:
https://bibliotekanauki.pl/articles/2037124.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.30.Sg
75.30.Kz
75.80.+q
Opis:
A study of the magnetocaloric properties of La$\text{}_{1-x-y}$Y$\text{}_{y}$Ca$\text{}_{x}$MnO$\text{}_{3}$, La$\text{}_{1-x}$Cd$\text{}_{x}$MnO$\text{}_{3}$, and Pr$\text{}_{1-x}$Ca$\text{}_{x}$MnO$\text{}_{3}$ manganites with ferromagnetic and charge-ordered states is presented. The ferromagnetic lanthanum manganites show a negative entropy change peakΔ S under the application of a magnetic field at the Curie temperature. However, the magnetoelastic coupling effects lead to a first-order paramagnetic-ferromagn etic transition and an increasedΔ S compared to simple ferromagnets. This effect is analyzed in the framework of the Landau theory of phase transitions which shows a comparable influence of the magnetoelastic couplings and the ordinary magnetic ordering effect. The Pr$\text{}_{1-x}$Ca$\text{}_{x}$MnO $\text{}_{3}$ system shows a rich electric and magnetic phase diagram, with a ferromagnetic insulator phase for 0.15
Źródło:
Acta Physica Polonica A; 2004, 105, 1-2; 163-171
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Large Magnetocaloric Effect in $Nd_{2}Ni_{2}In$
Autorzy:
Maskova, S.
Danis, S.
Llobet, A.
Nakotte, H.
Havela, L.
Powiązania:
https://bibliotekanauki.pl/articles/1368761.pdf
Data publikacji:
2014-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Ee
75.30.Kz
75.30.Sg
Opis:
$Nd_{2}Ni_{2}In$ is an antiferromagnet ($T_{N}$=8 K) with crystal structure equivalent to the Shastry-Sutherland lattice, possibly leading to the magnetic frustration. The AF coupling with moments in the basal plane can be driven by weak magnetic fields (<0.2 T) into the c-axis ferromagnet. The situation leads to large changes of magnetic entropy in fields below 1 T, which makes $Nd_{2}Ni_{2}In$ a candidate for magnetocaloric applications. The entropy change is 9.6 J/(kg K) in fields of 1 T.
Źródło:
Acta Physica Polonica A; 2014, 126, 1; 282-283
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inverse magnetocaloric effect in spin-1/2 Fishers super-exchange antiferromagnet
Autorzy:
Gálisová, L.
Strečka, J.
Powiązania:
https://bibliotekanauki.pl/articles/1052954.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
05.50.+q
75.30.Et
75.30.Sg
75.30.Kz
Opis:
The isothermal entropy change and the adiabatic temperature change are rigorously calculated for the exactly solved spin-1/2 Fisher's super-exchange antiferromagnet in order to examine magnetocaloric properties of the model in a vicinity of the second-order phase transition. It is shown that the large inverse magnetocaloric effect occurs around the temperature interval T_c(h≠0) < T < T_c(h=0) for any magnetic-field change Δh:0 → h. The most pronounced inverse magnetocaloric effect can be found for the magnetic-field change, which coincides with the critical field of a zero-temperature phase transition from the antiferromagnetically ordered ground state to the paramagnetic one.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 627-629
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Systems at Criticality: Different Signatures of Scaling
Autorzy:
Pełka, R.
Konieczny, P.
Fitta, M.
Czapla, M.
Zieliński, P.
Bałanda, M.
Wasiutyński, T.
Miyazaki, Y.
Inaba, A.
Pinkowicz, D.
Sieklucka, B.
Powiązania:
https://bibliotekanauki.pl/articles/1399023.pdf
Data publikacji:
2013-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.40.-s
75.30.Kz
75.30.Sg
75.50.Xx
Opis:
Different aspects of critical behaviour of magnetic materials are presented and discussed. The scaling ideas are shown to arise in the context of purely magnetic properties as well as in that of thermal properties as demonstrated by magnetocaloric effect or combined scaling of excess entropy and order parameter. Two non-standard approaches to scaling phenomena are described. The presented concepts are exemplified by experimental data gathered on four representatives of molecular magnets.
Źródło:
Acta Physica Polonica A; 2013, 124, 6; 977-989
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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