Scan Science and Technology
Contact Leading Edge Experts & Companies
Adiabatic Temperature
The Experts below are selected from a list of 40593 Experts worldwide ranked by ideXlab platform
Mehmet Acet – One of the best experts on this subject based on the ideXlab platform.
-
Dynamics of the magnetoelastic phase transition and Adiabatic Temperature change in Mn1.3Fe0.7P0.5Si0.55
Journal of Magnetism and Magnetic Materials, 2019Co-Authors: Maximilian Fries, Konstantin P. Skokov, Mehmet Acet, Tino Gottschall, Franziska Scheibel, Lukas Pfeuffer, I. Skourski, Michael Farle, Jochen Wosnitza, Oliver GutfleischAbstract:Abstract The Adiabatic Temperature change Δ T ad of a Mn 1.3 Fe 0.7 P 0.5 Si 0.55 Fe 2 P-type alloy was measured under different magnetic field-sweep rates from 0.93 Ts−1 to 2870 Ts−1. We find a field-sweep-rate independent magnetocaloric effect due to a partial alignment of magnetic moments in the paramagnetic region overlapping with the magnetocaloric effect of the first-order phase transition. Additionally, the first-order phase transition is not completed even in fields up to 20 T leading to a non-saturating behavior of Δ T ad . Measurements in different pulsed fields reveal that the first-order phase transition cannot follow the fast field changes as previously assumed, resulting in a distinct field-dependent hysteresis in Δ T ad .
-
Reversibility in the Adiabatic Temperature-change of Pr0.73Pb0.27MnO3
Journal of Alloys and Compounds, 2013Co-Authors: Selda Kılıç Çetin, Mehmet Acet, Ahmet Ekicibil, Cengiz Sarikurkcu, Kerim KiymaçAbstract:Abstract The investigation of structure, magnetic and magnetocaloric properties of Pr 0.73 Pb 0.27 MnO 3 perovskite has been studied by using the X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and magnetization. The X-ray diffraction pattern shows reflections typical of the perovskite structure with cubic symmetry. The field cooled (FC), zero-field-cooled (ZFC) and field-heated (FH) thermomagnetic measurements at 50 Oe indicate a sharp change of magnetization at the phase-transition ( T C ≈ 234 K). The magnetic entropy changes were determined from M ( H ) isotherms that were measured at various Temperatures around T C . The magnetic entropy changes in magnetic field changes of 1 T and 2 T were 2 . 4 J kg − 1 K − 1 and 3 . 8 J kg − 1 K − 1 , respectively. The Adiabatic Temperature change of this material, Δ T ad , was measured by means of an Adiabatic calorimeter directly. The results indicate a maximum Adiabatic Temperature change produced by a magnetic field change of 3 T is 2.5 K at 236 K.
-
Adiabatic Temperature change around coinciding first and second order magnetic transitions in Mn3Ga(C0.85N0.15)
Journal of Magnetism and Magnetic Materials, 2013Co-Authors: Orhan Çakır, Mehmet AcetAbstract:Abstract The inverse magnetocaloric material in Mn 3 GaC relies on the presence of a first order antiferromagnetic–ferromagnetic transition at around 160 K. Since Mn 3 GaN is antiferromagnetic, the partial substitution of carbon by nitrogen in Mn 3 GaC enhances the antiferromagnetic exchange and shifts this transition to higher Temperatures. At the Mn 3 Ga(C 0.85 N 0.15 ) stoichiometry, the transition takes place at 180 K. The hysteresis at the transition reduces so that the inverse magnetocaloric effect is practically reversible. We study the magnetocaloric effect and the reversibility of the Adiabatic Temperature-change by magnetization and direct Temperature-change measurements up to field-changes of 5 T.
Jin-keun Kim – One of the best experts on this subject based on the ideXlab platform.
-
Prediction of concrete Adiabatic Temperature rise characteristic by semi-Adiabatic Temperature rise test and FEM analysis
Construction and Building Materials, 2016Co-Authors: Chang-keun Lim, Jin-keun Kim, Tae-seok SeoAbstract:Abstract Concrete Temperature criteria, such as the maximum Temperature limit and the maximum Temperature difference limit between the interior and exterior of concrete, have become more stringent in recent construction projects. Therefore, the prediction of concrete Temperature through thermal analysis is becoming a serious issue. The accuracy of Temperature prediction through FEM analysis depends on the input values of concrete thermal properties, and one of the most important properties of concrete is its Adiabatic Temperature rise characteristic. An Adiabatic Temperature rise test can determine the most accurate Adiabatic Temperature rise characteristic of concrete. However, the test equipment is expensive, and not many agencies can perform the test. In this study, a new method that can be easily applied to mass concrete structures and has a high accuracy was developed for predicting concrete Adiabatic Temperature rise characteristic. Adiabatic Temperature rise characteristic were predicted through a combination of a simple semi-Adiabatic Temperature rise test and a FEM analysis. In order to check its accuracy, the results of the new method were compared with that of a direct Adiabatic Temperature rise test. The predicted Adiabatic Temperature rise characteristic were used to numerically analyze the Temperature behavior of a concrete structure. Then, a real concrete structure was built, and the Temperature of concrete was measured. Finally, the validity of the new method was verified by comparing the results from the thermal analysis with the measurements of the real structure.
-
Development of a portable device and compensation method for the prediction of the Adiabatic Temperature rise of concrete
Construction and Building Materials, 2016Co-Authors: Jae-min Park, Sang-lyul Cha, Jin-keun KimAbstract:Abstract Semi-Adiabatic devices are widely used as a substitute for the Adiabatic calorimeter to predict Adiabatic Temperature rise. The maximum Temperature and the reaction rate in the Adiabatic Temperature rise are important parameters to demonstrate the thermal characteristic and mechanical properties of concrete. However, the existing method for the prediction of the Adiabatic Temperature rise from semi-Adiabatic device only includes heat loss compensation, which is related to the maximum Temperature, though the reaction rate is even more important. Therefore, a new compensation method regarding the reaction rate is suggested in this paper. It improves the accuracy of prediction of Adiabatic Temperature rise.
Tae-seok Seo – One of the best experts on this subject based on the ideXlab platform.
-
Prediction of concrete Adiabatic Temperature rise characteristic by semi-Adiabatic Temperature rise test and FEM analysis
Construction and Building Materials, 2016Co-Authors: Chang-keun Lim, Jin-keun Kim, Tae-seok SeoAbstract:Abstract Concrete Temperature criteria, such as the maximum Temperature limit and the maximum Temperature difference limit between the interior and exterior of concrete, have become more stringent in recent construction projects. Therefore, the prediction of concrete Temperature through thermal analysis is becoming a serious issue. The accuracy of Temperature prediction through FEM analysis depends on the input values of concrete thermal properties, and one of the most important properties of concrete is its Adiabatic Temperature rise characteristic. An Adiabatic Temperature rise test can determine the most accurate Adiabatic Temperature rise characteristic of concrete. However, the test equipment is expensive, and not many agencies can perform the test. In this study, a new method that can be easily applied to mass concrete structures and has a high accuracy was developed for predicting concrete Adiabatic Temperature rise characteristic. Adiabatic Temperature rise characteristic were predicted through a combination of a simple semi-Adiabatic Temperature rise test and a FEM analysis. In order to check its accuracy, the results of the new method were compared with that of a direct Adiabatic Temperature rise test. The predicted Adiabatic Temperature rise characteristic were used to numerically analyze the Temperature behavior of a concrete structure. Then, a real concrete structure was built, and the Temperature of concrete was measured. Finally, the validity of the new method was verified by comparing the results from the thermal analysis with the measurements of the real structure.