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Tytuł:
Continuity Versus Innovation: Young Polish Migrants and Practices of ‘Doing Family’ in the Context of Achieving Independence in the UK
Autorzy:
Heath, Sue
McGhee, Derek
Trevena, Paulina
Powiązania:
https://bibliotekanauki.pl/articles/579884.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
A8 MIGRANTS
YOUTH TRANSITIONS
FAMILY
Opis:
This paper explores continuity and innovation in the everyday relational practices of a group of post-accession Polish migrants who first arrived in the UK when in their late teens and twenties. In the context of claims that migration has allowed younger migrants to pursue lives free from familial ties and responsibilities, the paper focuses on their living arrangements in the UK and the extent to which they actively eschew or embrace familial relationships, practices and commitments. Our data suggest that moving to the UK had undoubtedly facilitated new freedoms and opportunities, yet these were utilised by many to bring forward, rather than delay, a sequence of broadly conventional domestic transitions, accompanied for many by ongoing dependency and interconnectedness with networks of extended family members who had also migrated to the UK. Our paper draws on the concepts of frontiering and relativising (Bryceson and Vuorela 2002) and argues that our participants were engaged in sets of practices linked to both. Further, these practices not only entailed a continual revision of migrants’ sense of family identity, affected by life stage, but were also underpinned for many by the centrality of traditional conceptualisations of family.
Źródło:
Studia Migracyjne - Przegląd Polonijny; 2015, 41, 3 (157); 139-156
2081-4488
2544-4972
Pojawia się w:
Studia Migracyjne - Przegląd Polonijny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Alternative, Direct Synthesis Method of the Ceramic Solid Solutions Based on BaTiO3 Through a High Energy Ball Milling
Autorzy:
Bąk, W.
Dulian, P.
Garbarz-Glos, B.
Czekaj, D.
Lisińska-Czekaj, A.
Powiązania:
https://bibliotekanauki.pl/articles/351595.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ceramics
mechanochemical synthesis
dielectric properties
phase transitions
ferroelectrics
Opis:
Polycrystalline samples BaTiO3 and the solid solutions Ba0.9 Sr0.1 TiO3, 0.9 Sr0.1 Ti0.9 Sn0.1 O3, Ba0.9 Sr0.1 Ti0.8 Sn0.2 O3 were obtained by means of a mechanochemical treatment based on the high-energy ball milling technique and next a high temperature solid state reaction method. The influence of synthesis condition on microstructural, dielectric and ferroelectric properties of obtained solid solutions were investigated. The structure and morphology of the investigated samples were characterized by an X-ray diffraction (XRD) and scanning electron microscopy (SEM). The characterization of electrical properties of the ceramics within the temperature range from –130°C to 250°C were performed by means of a dielectric spectroscopy method at the frequency ranging from 0.1 Hz to10 MHz. The diffusion of the paraelectric – ferroelectric phase transition and dielectric relaxation for ceramic samples are described.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 2; 805-810
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Longer-Term Demographic Dynamics in South-East Europe: Convergent, Divergent and Delayed Development Paths
Autorzy:
Fassmann, Heinz
Musil, Elisabeth
Bauer, Ramon
Melegh, Attila
Gruber, Kathrin
Powiązania:
https://bibliotekanauki.pl/articles/498627.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
demographic change
migration cycle
transitions
South-East Europe
Opis:
This article offers an overview of the longer-term migratory and demographic developments in eight South-East European countries (Austria, Bulgaria, Italy, Hungary, Romania, Serbia, Slovenia and Slovakia). The main research question aims to analyse the different demographic historical developments and to examine whether convergent or divergent processes are dominant. Over the whole reference period, the population size in these eight South-East European countries (the SEEMIG region) grew from around 100 million people in 1950 to 122 million in 2011. This is surprising, as the public image of the region is linked to decline and backwardness and to being peripheral. However, major differences in the demographic developments of the countries can be observed. Some countries, including Austria, Italy and, with some fluctuations, Slovakia and Slovenia, experienced constant population growth during the entire reference period. All other countries were affected by a decrease in population, as was the case for Hungary in the early 1980s, Bulgaria at the beginning of the 1990s and Serbia and Romania since the start of the new millennium. The fertility trend shows a convergence while the mortality trends (including average life expectancy at birth) prove to be divergent. The net migration pattern seems to follow a migration cycle concept which postulates a general shift from emigration to immigration as a consequence of a declining natural increase on the one hand and a growing demand for new labour on the other. Some countries show trends that do not yet follow this pattern, which might indicate that additional factors and interpretative models should also be taken into account. The long-term distribution of growth and decline in the region is quite diverse and underlines the need for differentiation and specific explanations.
Źródło:
Central and Eastern European Migration Review; 2014, 3, 2; 150-172
2300-1682
Pojawia się w:
Central and Eastern European Migration Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of Mo Content on Phase Transformation in Ti-Mo Alloys
Autorzy:
Sochacka, P.
Miklaszewski, A.
Jurczyk, M.
Powiązania:
https://bibliotekanauki.pl/articles/351258.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
titanium
molybdenum
biomaterials
mechanical alloying
phase transitions α-β
Opis:
Titanium β-type alloys are a class of interesting biomaterials that can exhibit a unique combination of mechanical as well as physicochemical and biological properties. The aim of this study is to develop a titanium-molybdenum alloys (Ti-x at % Mo, x = 15 and 23). These materials were prepared by the combination of mechanical alloying and powder metallurgical process. The details of the processing method were presented. The samples were characterized by X-ray diffraction, scanning electron micros-copy, chemical composition determination as well as density and Vickers microhardness measurements. The corrosion behaviour in Ringer solution was investigated, too. The crystallization of the obtained material upon annealing led to the formation of a near single β type alloys. The molybdenum content in titanium and heat treatment parameters of a nearly amorphous phase allow to synthesize Ti(β)-type alloys. The present study has demonstrated that Ti23Mo alloy can be the next generation of biomaterial for bone tissue engineering.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 4; 2051-2056
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of Pb1-xBax(Zr1-yTiy)1-zSnzO3 (x = 0.03, y = 0.02, z = 0÷0.08) Ceramics
Autorzy:
Brzezińska, D.
Powiązania:
https://bibliotekanauki.pl/articles/354740.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
PBZT and PBZTS ceramics
phase transitions
dielectric properties
electrical conductivity
Opis:
This paper presents the results of obtaining and investigations of Pb1-xBax(Zr1-yTiy)1-zSnzO33(PBZTS) ceramics with constant x = 0.03 and y = 0.02, and variable z = 0, 0.04, 0.06 and 0.08 (abbreviations of the samples were following PBZTS0, PBZTS4, PBZTS6, PBZTS8, respectively). The investigated compositions are close to rhombohedral-orthorhombic morphotropic phase boundary. The ceramic samples have been obtained by conventional ceramic technology from simple oxides PbO, ZrO2, TiO2, SnO2 and barium carbonate BaCO3. The ceramic powders, after calcination, have been pressed into discs and sintered using free sintering (FS) method. For samples obtained in such a way, the dielectric properties at various frequencies and electrical conductivity have been investigated. The increase of Sn content orders the microstructure of ceramics, and as a result the improvement of the dielectric properties of ceramic samples can be obtained.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 2; 975-982
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identity and markers of adulthood: the relationship between two constructs
Autorzy:
Brzezińska, Anna Izabela
Piotrowski, Konrad
Powiązania:
https://bibliotekanauki.pl/articles/430424.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
commitment
exploration
identity formation
psychosocial maturity
role transitions
sense of adulthood
Opis:
The article presents both the classical and contemporary approaches to the analysis of identity formation. Special emphasis has been placed on the processual approach, in which identity is regarded as a dynamic construct that remains in constant, mutual relations with personal and contextual factors. Since research on identity has been predominantly based on studies conducted on individuals in adolescence and early adulthood, i.e. in the time of transition to adulthood, the article focuses on adulthood markers that may be found in this particular phase of human development. The authors have distinguished different markers of adulthood (transitions to adult roles, psychosocial maturity, sense of adulthood) and have described their links to identity. In the conclusion of the present paper, it has been stressed that future research on identity should to a large extent include factors originating from these different categories of conditions, and that researchers ought to consider the interactions of these factors as predictors of identity formation.
Źródło:
Polish Psychological Bulletin; 2013, 44, 3; 254-265
0079-2993
Pojawia się w:
Polish Psychological Bulletin
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Semiconductor Element Substitution on the Electric Properties of Barium Titanate Ceramics
Autorzy:
Garbarz-Glos, B.
Lisińska-Czekaj, A.
Czekaj, D.
Bąk, W.
Powiązania:
https://bibliotekanauki.pl/articles/354672.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
barium titanate
ceramics
dielectric permittivity
electric conductivity
phase transitions
PTCR effect
Opis:
The investigated ceramics were prepared by a solid-state reaction from simple oxides and carbonates with the use of a mixed oxide method (MOM). The morphology of BaTi0.96Si0.04O3 (BTSi04) ceramics was characterised by means of a scanning electron microscopy (SEM). It was found that Si+4 ion substitution supported the grain growth process in BT-based ceramics. The EDS results confirmed the high purity and expected quantitative composition of the synthesized material. The dielectric properties of the ceramics were also determined within the temperature range (ΔT=130-500K). It was found that the substitution of Si+4 ions had a significant influence on temperature behavior of the real (ε’) and imaginary (ε”) parts of electric permittivity as well as the temperature dependence of a.c. conductivity. Temperature regions of PTCR effect (positive temperature coefficient of resistivity) were determined for BTSi04 ceramics in the vicinity of structural phase transitions typical for barium titanate. No distinct maximum indicating a low-temperature structural transition to a rhombohedral phase in BTSi04 was found. The activation energy of conductivity was determined from the Arrhenius plots. It was found that substitution of Si ions in amount of 4wt.% caused almost 50% decrease in an activation energy value.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 2A; 887-890
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Diffusive and Displacive Phase Transformations in Nanocomposites under High Pressure Torsion
Autorzy:
Straumal, B.
Kilmametov, A.
Gornakova, A.
Mazilkin, A.
Baretzky, B.
Korneva, A.
Zięba, P.
Powiązania:
https://bibliotekanauki.pl/articles/356575.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high-pressure torsion
Ti-Fe alloys
phase transitions
high-pressure phases
Opis:
The high-pressure torsion (HPT) of Ti-Fe alloys with different iron content has been studied at 7 GPa, 5 anvil rotations and rotation speed of 1 rpm. The alloys have been annealed before HPT in such a way that they contained different amounts of α/α' and β phases. In turn, the β phase contained different concentration of iron. The 5 anvil rotations correspond to the HPT steady-state and to the dynamic equilibrium between formation and annihilation of microstructure defects. HPT leads to the transformation of initial α/α' and β-phases into mixture of α and high-pressure ω-phase. The α → ω and β → ω phase transformations are martensitic, and certain orientation relationships exist between α and ω as well as β and ω phases. However, the composition of ω-phase is the same in all samples after HPT and does not depend on the composition of β-phase (which is different in different initial samples). Therefore, the martensitic (diffusionless) transformations are combined with a certain HPT-driven mass-transfer. We observed also that the structure and properties of phases (namely, α-Ti and ω-Ti) in the Ti – 2.2 wt. % Fe and Ti – 4 wt. % Fe alloys after HPT are equifinal and do not depend on the structure and properties of initial α'-Ti and β-Ti before HPT.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 2; 457-465
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Separate Kinetics of the Polar and Antiferrodistortive Order Parameters in the Antiferroelectric Transition of PbZr1-xTixO3 and the Influence of Defects
Oddzielne kinetyki polarnych i antyferroelektrycznych dystorsji parametrów uporządkowania w przemianie antyferroelektrycznej PBZR1-XTIXO3 oraz wpływ defektów
Autorzy:
Cordero, F.
Craciun, F.
Trequattrini, F.
Galassi, C.
Powiązania:
https://bibliotekanauki.pl/articles/355151.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
antiferroelectric PZT
phase transitions
defect
elasticity
przemiana antyferroelektryczna
przejścia fazowe
defekt
elastyczność
Opis:
The transition from the rhombohedral-ferroelectric to the lower temperature orthorhombic-antiferroelectric phase in Zr-rich PZT involves two order parameters (OPs): 1) the polar OP for the displacements of the cations with respect to the O octahedra; 2) an antiferrodistortive OP responsible for tilting of the octahedra. It is shown that at Ti compositions near the morphotropic boundary with the FE phase (0.046 ≤ x ≤ 0.054), the two OPs may be almost independent of each other at cooling rates of 0.5 K/min or faster, depending on the sample history. This fact gives rise to a great variety of shapes of the curves of the elastic compliance s(T), but all of them can be fitted very well as superpositions of variously broadened steps for each of the modes involved in the transitions, including the tilt transition occurring in the untransformed FE fraction. The evolution of the s(T) curves includes enhancements up to a factor of four during aging for weeks in the region of the AFE/FE coexistence. Restiffening and reduction of the thermal hysteresis of the AFE/FE transition are recovered by heating up to 800-900 K. It is proposed that ageing is due to the clustering of relatively mobile defects, most likely O vacancies, at the domain walls in the coexisting AFE/FE phases. Such defect structures are probably at the origin of intense thermally activated relaxation processes observed above TC in the dielectric and anelastic spectra, and can be annealed out above 800 K, allowing the AFE transition to recover a fast kinetics.
Przemiana fazy romboedrycznej-ferroelektrycznej do niskotemperaturowej fazy rombowej-antyferroelektrycznej bogatej w Zr ceramiki piezoelektrycznej PZT obejmuje dwa parametry uporządkowania (OP): 1) polarny OP z przemieszczeń kationów Zr/Ti w odniesieniu do oktaedrów tlenowych; 2) antyferroelektryczna dystorsja OP odpowiedzialna za przechylenie oktaedrów. Pokazano, że dla zawartości Ti w pobliżu morfotropowej granicy z fazą ferroelektryczną (0,046≤x≤0,054), obydwa OP mogą być prawie niezależne od siebie podczas chłodzenia z szybkością 0,5 K/min lub mniejszą, w zależności od historii próbki. Ten fakt powoduje wielką różnorodność kształtów krzywych podatności sprężystej s(T), ale wszystkie z nich mogą być bardzo dobrze przybliżone jako superpozycje różnie poszerzonych etapów dla każdego z trybów zaangażowanych w przemianę, w tym przemianę nachylenia występującą w nietransformowanej fazie ferroelektrycznej. Zmiana krzywych s(T) obejmuje czterokrotne poszerzenia krzywych po okresie starzenia przez kilka tygodni w regionie współistnienia faz antyferroelektrycznej (AFE) i ferroelektrycznej (FE). Zesztywnienie i zwężenie pętli histerezy termicznej przemiany AFE / FE są odzyskiwane przez podgrzanie do temperatury 800-900 K. Proponuje się, że starzenie się jest spowodowane grupowaniem się stosunkowo mobilnych defektów, najprawdopodobniej wakansów tlenowych, na ścianach domen w współistniejących fazach AFE / FE. Defekty te są zapewne przyczyną silnych, aktywowanych termicznie procesów relaksacyjnych obserwowanych powyżej temperatury krytycznej TC w widmie strat dielektrycznych i mechanicznych, i mogą być wyżarzane powyżej 800 K, umożliwiając przejściu AFE odzyskanie szybkiej kinetyki przemiany.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 1; 381-384
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Phase Transitions in BNT-BT Lead-Free Ceramics Around Morphotropic Phase Boundary by Mechanical and Dielectric Spectroscopies
Autorzy:
Silva Jr, P. S.
Diaz, J. C. C. A.
Florêncio, O.
Venet, M.
M’Peko, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/353072.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Lead-free piezoelectric ceramics
morphotropic phase boundary
phase transitions
mechanical spectroscopy
dielectric spectroscopy
Opis:
In this work, the syntheses and characterization by mechanical and dielectric spectroscopies of (1-x) Bi0.5Na0.5TiO3-xBaTiO3 (BNT-100xBT), with x = 0.05, 0.06 and 0.07, lead-free piezoelectric ceramics is reported. Ceramic samples of BNT-BT have been prepared by mixed-oxide method and then conventionally sintered. X-ray diffraction patterns of sintered samples, indicated for BNT-7BT the presence of tetragonal (P4mm) complex perovskite structure, whereas for BNT-5BT and BNT-6BT the samples exhibit a mixture of tetragonal (P4mm) and rhombohedral (R3c) crystalline phases, which reveal the presence of a morphotropic phase boundary (MPB) in the BNT-BT system. Measurements of internal friction, Q-1, and the storage modulus, E’, as a function of temperature at various frequencies were carried out in a Dynamic Mechanical Analyzer (DMA), in the temperature range from 0ºC to 600ºC. Dielectric profiles are recorded in the frequency range from 1kHz to 100kHz and the temperature range from room temperature to 475ºC. Mechanical loss spectra obtained for investigated compositions of BNT-BT samples showed different frequency-independent anomalies. Two main anomalies for BNT-5BT and BNT-6BT, observed around 100ºC and 430ºC were associated with the ferroelectric-antiferroelectric and antiferroelectricparaelectric phase transitions, respectively. The results obtained from mechanical loss measurements were supported by dielectric relaxation spectra. For BNT-7BT, outside the MPB, four different frequency-independent processes were observed.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 17-20
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The properties of Pbzts ceramics near orthorhombic-rhombohedral morphotropic phase boundary
Właściwości ceramiki PBZTS w pobliżu granicy morfotropowej pomiędzy fazą ortorombową i romboedryczną
Autorzy:
Brzezińska, D.
Skulski, R.
Wawrzała, P.
Powiązania:
https://bibliotekanauki.pl/articles/352950.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
ceramika PBZT i PBZTS
przejścia fazowe
właściwości dielektryczne
PBZT and PBZTS ceramics
phase transitions
dielectric properties
Opis:
We present the results of obtaining and investigations of (Pb1-xBax)((Zr1-yTiy)1-zSnz)O3 (PBZTS) ceramics with x=const=0.2, y=const=0.08, z=0, 0.02, 0.04, 0.06 and 0.08. Ceramic samples have been obtained by conventional ceramic technology from oxides PbO, ZrO2, TiO2, SnO2 and barium carbonate BaCO3. The calcination of powders was performed at Tcalc=850°C/tcalc=3h and next calcinated powders were pressed into discs and were sintered at Ts=1250°C/ts=4h using free sintering (FS) method. For such obtained samples the following investigations have been done: EDS, XRD, microstructure of fractured samples, dielectric measurements, P - E hysteresis loops investigations at various temperatures and electromechanical measurements at the room temperature using optical displacement meter. Investigated compositions are close to rhombohedral-orthorhombic morphotropic phase boundary. The results of dielectric and electromechanical properties are typical for ferroelectric materials.
Przedstawiono wyniki badań ceramiki (Pb1-xBax)((Zr1-yTiy)1-zSnz)O3 (PBZTS) dla stałych wartości parametrów x=0.2 i y=0.08 oraz dla różnych wartości z=0, 0.02, 0.04, 0.06, 0.08 Badana ceramika PBZTS została otrzymana z prostych tlenków PbO, ZrO2, TiO2, SnO2 i węglanu baru BaCO3. Syntezę proszków przeprowadzono metodą kalcynacji w warunkach Tcalc=850_C/tcalc=3h, a następnie uformowano wypraski w formie dysków zagęszczono metodą swobodnego spiekania (FS) w warunkach Ts=1250_C/ts=4h. Dla otrzymanych próbek PBZT/PBZTS przeprowadzono badania EDS, XRD, badania mikrostruktury przełamów, badania przenikalnosci elektrycznej i tangensa kąta strat dielektrycznych, badania pętli histerezy w różnych temperaturach oraz badania elektromechaniczne w temperaturze pokojowej przy użyciu optycznego miernika przesunięcia. Wybrane składy PBZTS znajdują się w pobliżu granicy fazowej między fazami o romboedrycznej i ortorombowej deformacji komórek elementarnych. Z badań dielektrycznych i elektromechanicznych wynika, iż jest to materiał ferroelektryczny.
Źródło:
Archives of Metallurgy and Materials; 2011, 56, 4; 1243-1247
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The properties of (Pb0.97Ba0.03)[(Zr0.98Ti0.02)1-zSnz]O3 ceramics with 0 < z < 0.08
Właściwości ceramiki (Pb0.97Ba0.03)[(Zr0.98Ti0.02)1-zSnz]O3 o wartościach 0 < z < 0,08
Autorzy:
Brzezińska, D.
Skulski, R.
Wawrzała, P.
Dercz, G.
Powiązania:
https://bibliotekanauki.pl/articles/352351.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
PBZT and PBZTS ceramics
phase transitions
dielectric properties
ceramika PBZT i PBZTS
przejście fazowe
właściwości dielektryczne
Opis:
We present the results of obtaining and investigations of (Pb1-x Bax )((Zr1-yTiy) 1-zSnz )O3 (PBZTS) ceramics with x =const =0.03, y =const=0.02, z =0, 0.02, 0.04, 0.06 and 0.08. Investigated compositions are close to rhombohedral-orthorhombic morphotropic phase boundary. Ceramic samples have been obtained by conventional ceramic technology from oxides PbO, ZrO2, TiO2, SnO2 and barium carbonate BaCO3. The calcined powders were crushed and next pressed into discs and sintered free sintering (FS) method. For such obtained samples the following investigations have been done: EDS, XRD, microstructure of fractured samples, dielectric measurements, P-Ehysteresis loops investigations at various temperatures.
Przedstawiono wyniki badań ceramiki (Pb1-x Bax )((Zr1-yTiy) 1-zSnz )O3 (PBZTS) dla stałych wartości parametrów ,v =0,03 i y =0,02 oraz z =0, 0,02, 0,04, 0,06 i 0,08. Badane składy PBZTS znajdują się w pobliżu granicy fazowej między fazami o romboedrycznej i ortorombowej deformacji komórek elementarnych. Ceramiczne próbki PBZTS zostały otrzymane z prostych tlenków PbO, ZrO2, TiO2, SnO2 i węglanu baru BaCO3. Proszki po kalcynacji zostały rozdrobnione, a następnie uformowano z nich wypraski i zagęszczono metodą swobodnego spiekania (FS). Dla otrzymanych próbek PBZT/PBZTS przeprowadzono badania EDS, XRD, badania mikrostruktury przełamów, badania podstawowych właściwości dielektrycznych, badania pętli histerezy w różnych temperaturach.
Źródło:
Archives of Metallurgy and Materials; 2013, 58, 4; 1377-1380
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Youth, Mobility and Generations – the Meanings and Impact of Migration and Mobility Experiences on Transitions to Adulthood
Autorzy:
Krzaklewska, Ewa
Powiązania:
https://bibliotekanauki.pl/articles/579663.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
MOBILITY
POST-ACCESSION MIGRATION FROM POLAND
TRANSITION TO ADULTHOOD
YOUTH TRANSITIONS
ADULTHOOD
YOUTH
RETURN MIGRANTS
GENERATION
Opis:
The article reflects on the role of mobility within transition to adulthood process. It will present the results of research focusing on the transitions to adulthood of representatives of the generation born at the beginning of the 1980s in Poland. This boom generation experienced both the transformation from a communist to a capitalist state, as well as the joyful and hopeful moment of Poland’s accession to the EU in 2004. Post-2004, faced with high unemployment, the representatives of this age cohort decided to leave Poland en masse in search of employment opportunities. Based on biographical interviews with young Poles born in the early 1980s and living in Poland, the article reflects upon the meaning of mobility and migration experiences in their young age. What was mobility impact on different transition to adulthood trajectories – employment, family or independent living? How has it affected the concept of adulthood? In the article, the mobility experience will be looked upon through the lenses of theories of youth studies, which is a recent trend in analyzing young people’s mobility or migration. The article points to the three meanings of mobility: mobility as an experience of semi-independence, mobility as time to gain adulthood, and mobility as a celebration of youth. As the experience of this cohort is unique in the historical sense, it is also exemplary for the growing importance of mobility in transitions to adulthood.
Źródło:
Studia Migracyjne - Przegląd Polonijny; 2019, 45, 1 (171); 41-59
2081-4488
2544-4972
Pojawia się w:
Studia Migracyjne - Przegląd Polonijny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Problems of Transition Predicates Construction in Hierarchical Concurrent Controllers
Autorzy:
Łabiak, G.
Powiązania:
https://bibliotekanauki.pl/articles/226340.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
binary control system
statechart diagrams
hierarchy;concurrency
conflicting transitions
Boolean predicates
computational complexity
compatibility classes
clique problem
Opis:
The paper presents a problem of a transition predicates construction in hierarchical concurrent state oriented notation. The notation, called statechart diagrams or state machine, serves as a very convenient formalism for specification of a complex behavior of the embedded systems control unit. The controller specified in this way is discrete, deterministic and synchronous system which operates on binary values and can be implemented in programmable devices as a digital circuit. Well designed controller has conflict-free transitions and its concurrent transitions should be independent. In order to meet this requirements transition predicates must be pairwise both orthogonal and non-implicative. Computational complexities of the problems is equal to classic clique problem. The paper also suggests some statecharts syntactic structures solving these problems.
Źródło:
International Journal of Electronics and Telecommunications; 2012, 58, 4; 411-418
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Thermal Analysis Tests Results in the Numerical Simulations of Continuous Casting Process
Zastosowanie wyników badań analizy termicznej w obliczeniach numerycznych procesów odlewania stali
Autorzy:
Kargul, T.
Wielgosz, E
Falkus, J.
Powiązania:
https://bibliotekanauki.pl/articles/353992.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
thermal analysis of steel
specific heat
enthalpy of phase transitions
steel
analiza termiczna stali
ciepło właściwe
entalpia przemian fazowych
stal
Opis:
Measurement of thermophysical properties of steel is possible by using different thermal analysis techniques. In the field of metallurgy the most relevant methods are Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). The paper presents the results of thermophysical properties which are necessary to carry out numerical simulation of continuous casting of steel. The study was performed for two steel grades S320GD and S235JR. The main aim of the research was to determine the dependence of specific heat on temperature. On the basis of obtained results the thermal effects of phase transformations and characteristic transition temperatures were also identified. Both the specific heat of steel and thermal effects of phase transformations are included in the Fourier-Kirchhoff equation, as the material properties necessary to obtain the numerical solution. The paper presents the research methodology, analysis of results and method of determining the specific heat of steel based on the results of DSC analysis.
Pomiar właściwości termofizycznych stali możliwy jest dzięki wykorzystaniu różnych technik analizy termicznej. W metalurgii najszersze zastosowanie znalazły różnicowa analiza termiczna (DTA) oraz różnicowa kalorymetria skaningowa (DSC). W pracy przedstawiono wyniki badań właściwości termofizycznych koniecznych do przeprowadzenia symulacji numerycznej procesu ciągłego odlewania stali. Badania wykonano dla dwóch gatunków stali S320GD i S235JR. Głównym celem badań było wyznaczenie funkcyjnej zależności ciepła właściwego analizowanych gatunków stali od temperatury. Na podstawie przeprowadzonych badań określono również efekty cieplne przemian fazowych oraz charakterystyczne temperatury przemian. Zarówno ciepło właściwe stali jak i efekty cieplne przemian fazowych wchodzą w skład równania Fouriera-Kirchhoffa, jako właściwości materiałowe konieczne do uzyskania rozwiązania numerycznego. W pracy przedstawiono metodykę badań, analizę uzyskanych wyników oraz sposób wyznaczania ciepła właściwego stali w oparciu wyniki analizy DSC.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 1; 221-225
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 16

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