Környezettudatos cselekedetek motivációi magyar diákok körében

A környezettudatosság korunk fontos kérdésköre, ennek megfelelően már több pszichológiai kutatás is foglalkozott azzal, milyen aspektusok határozzák meg, hogy az egyének végrehajtanak-e környezetbarát cselekedeteket. Azonban a magyar populáció körében ezen – már meglévő – elméletek és modellek alkalmazhatósága nincs megfelelően felmérve. Ezért ebben a kutatásban kvalitatív módszertannal, interjúkon keresztül vizsgáljuk, hogy a magyar fiatalok milyen motiváló erőket említenek, melyek saját és mások cselekedeteit irányítják környezettudatos cselekedetek elvégzésére. A minta 10 fő, 22 éven aluli magyar fiatalból állt (16-22 év, M=18,9 év, SD=2,13). A velük készült interjúk átiratainak elemzése és kódolása során több motivációs címke került azonosításra, melyeket a Theory of Planned Behaviour (Tervezett cselekvés elmélete, továbbiakban TPB) és a Value-Belief-Norm (Érték-meggyőződés-norma elmélet, továbbiakban VBN) elmélet modelljeinek elemeivel hasonlítottunk össze. Az eredmények alapján az előbb említett két modell aspektusai megjelennek az interjúk átirataiban, de hiányoznak az elméletekből az interjúkban többször is említett érzelmi és a lehetséges társas, vagy anyagi nyereségek hatásai. Így összesen 4 témát: Társas motivációk, Nyereség, Intrinzik, személyes motiváló tényezők és Nem társas külső motiváló tényezők lehetett megkülönböztetni, melyek jól lefedik a felmerült szövegtartalmakat. Ezeken felül a VBN és TPB modellek egyes részeinek megjelenése kevésbé volt központi az eredeti nyugat-európai és amerikai populációhoz képest. Az eltérés hátterében kulturális és gazdasági okok is állhatnak

Influence of Degree of Severe Plastic Deformation on Thermal Stability of an HfNbTiZr Multi-Principal Element Alloy Processed by High-Pressure Torsion

Severe plastic deformation (SPD) is an effective route for the nanocrystallization of multi-principal element alloys (MPEAs). The stability of the refined microstructure is important, considering the high temperature applications of these materials. In the present study, the effect of SPD on the stability of a body-centered cubic (bcc) HfNbTiZr MPEA was investigated. SPD was performed using a high-pressure torsion (HPT) technique by varying the number of turns between ½ and 10. The evolution of phase composition and microstructure was studied near the disk centers and edges where the imposed strain values were the lowest and highest, respectively. Thus, the shear strain caused by HPT varies between 3 (½ turn, near the center) and 340 (10 turns, near the edge). It was found that during annealing up to 1000 K, the bcc HfNbTiZr alloy decomposed into two bcc phases with different lattice constants at 740 K. In addition, at high strains a hexagonal close packed (hcp) phase was formed above 890 K. An inhomogeneous elemental distribution was developed at temperatures higher than 890 K due to the phase decomposition. The scale of the chemical heterogeneities decreased from about 10 µm to 30 nm where the shear strain increased from 3 to 340, which is similar to the magnitude of grain refinement. Anneal-induced hardening was observed in the MPEA after HPT for both low and high strains at 740 K, i.e., the hardness of the HPT-processed samples increased due to heat treatment. At low strain, the hardness remained practically unchanged between 740 and 1000 K, while for the alloy receiving high strains there was a softening in this temperature range

Thermal stability of nanocrystalline CoCrFeNi multi-principal element alloy: Effect of the degree of severe plastic deformation

The effect of the degree of severe plastic deformation (SPD) on the thermal stability of a nanocrystalline CoCrFeNi multi-principal element alloy was studied. The SPD method of high-pressure torsion (HPT) was utilized to achieve the nanocrystalline microstructure. The structural stability was investigated near the centers and edges of the HPT-processed disks deformed for ½, 1, 5 and 10 turns. For almost all studied samples, two exothermic peaks in the temperature ranges of 600–750 and 750–950 K were observed by differential scanning calorimetry (DSC) between room temperature and 1000 K. The saturation released heat value for the first DSC peak was about 4 J/g that was achieved at the shear strain of ∼200. For the second exothermic peak, the released heat saturated at the shear strain of about 20 with the value of about 6–7 J/g. It was revealed that the first DSC peak is related to the annihilation of dislocations for low degree of deformation. At the same time, for edge parts of the disks processed by one or higher numbers of turns the vacancy annihilation has also a major contribution to the first exothermic peak. The annihilated vacancy concentration estimated from the released heat was between (0.6–0.9) × 10−3. The second DSC peak was related to the disappearance of grain boundaries due to recrystallization and annihilation of the remaining dislocations. The HPT-processed CoCrFeNi MPEA samples exhibited very high hardness values between 4000 and 5100 MPa, depending on the number of turns and the location along the disk radius. The hardness decreased only during the second exothermic peak when recrystallization occurred

Water concentrations and hydrogen isotope compositions of alkaline basalt hosted clinopyroxene megacrysts and amphibole clinopyroxenites: the role of structural hydroxyl groups and molecular water

The aim of this study was to determine both 'water' contents (as OH- and H2O) and δD values of several clinopyroxene samples from alkaline basalts. These parameters were first obtained from five clinopyroxene samples using both the classical 'off-line' vacuum extraction technique and the 'on-line' high-temperature pyrolysis technique. Blanks measured with the 'on-line' gas extraction techniques were low enough to prevent any contamination by atmospheric water vapour. The comparison of data has revealed that the 'on-line' procedure is more effective for the extraction of 'water' from clinopyroxenes and, consequently, this 'on-line' technique was applied to ten additional clinopyroxene samples. Sample δD values cover a similar range from -95‰ to -45‰ (VSMOW) regardless the studied locations, whereas the total 'water' content varies from 1150 to 2570 ppm. The structural hydroxyl content of clinopyroxene samples measured by micro-FTIR spectrometry varies from ~0 to 476 ppm expressed in molecular water equivalent. There is a weak negative correlation between the total water concentrations determined by mass spectrometry and FTIR, thus indicating that considerable proportion of the 'water' may be present in (nano)-inclusions. It is observed, however, that the structural hydroxyl concentration - apart from linopyroxenes separated from amphibole clinopyroxenite xenoliths - correlates positively with the δD values of clinopyroxene megacrysts for each locality, indicating that structurally bond hydrogen in clinopyroxenes may have δD values higher than molecular water in inclusions. This implies that that there may be a significant hydrogen isotope fractionation for structural hydroxyl during crystallization of clinopyroxene while for molecular water there may be no or only negligible isotope fractionation