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Engineering

Selected Works

Shi Xue Dou

2014

Effect

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Magnetic Properties And Magnetocaloric Effect Of Ndmn2-Xcuxsi2 Compounds, M F. Md Din, Jianli Wang, M Avdeev, Q F. Gu, R Zeng, S J. Campbell, S J. Kennedy, S X. Dou Oct 2014

Magnetic Properties And Magnetocaloric Effect Of Ndmn2-Xcuxsi2 Compounds, M F. Md Din, Jianli Wang, M Avdeev, Q F. Gu, R Zeng, S J. Campbell, S J. Kennedy, S X. Dou

Shi Xue Dou

Structural and magnetic properties of NdMn2−x Cu xSi2 compounds (x = 0-1.0) have been investigated by high intensity x-ray and resolution neutron diffraction (3-450 K), specific heat, dc magnetization, and differential scanning calorimetry measurements. Substitution of Cu for Mn leads to an increase in the lattice parameter a but a decrease in c at room temperature. Two magnetic phase transitions have been found for NdMn2−x Cu xSi2 compounds with TN for the antiferromagnetic ordering of Mn-sublatttice and TC for the Nd-sublattice ferromagnetic ordering, respectively. TC increases significantly with increasing Cu content from 36 K at x = 0 to 100 …


Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou Mar 2014

Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou

Shi Xue Dou

The structural and magnetic properties of the intermetallic compounds NdMn2−xTixSi2(x = 0, 0.1, 0.2, and 0.3) have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3–450 K. The Curie temperature and Néel temperature of NdMn2Si2 decrease from TC = 36 K and TN = 380 K to TC = 14 K and TN = 360 K, respectively, on substitution of Ti (x = 0.3) for Mn. The magnetocaloric effect at the first order ferromagnetic phase transition at TC, has been investigated in detail. Under a …


Aging Effect Evolution During Ferroelectric-Ferroelectric Phase Transition: A Mechanism Study, Zuyong Feng, Zhenxiang Cheng, Dongqi Shi, S X. Dou Mar 2014

Aging Effect Evolution During Ferroelectric-Ferroelectric Phase Transition: A Mechanism Study, Zuyong Feng, Zhenxiang Cheng, Dongqi Shi, S X. Dou

Shi Xue Dou

Aging can significantly modify the dielectric, piezoelectric, and ferroelectric performance of ferroelectrics. However, little attention has been paid to the aging effect during ferroelectric-ferroelectric phase transitions that is essentially correlated with real applications. In this letter, the authors report the aging effect evolution between two ferroelectric phases in an acceptor-doped piezoceramics. The results show that aging-induced double hysteresis loops were exhibited in different ferroelectric phases, but disappeared during ferroelectric-ferroelectric phase transitions, suggesting the mechanism that the intrinsic restoring force for the reversible switching of domains caused by the alignment of defect dipoles was weakened due to ferroelectric dipole reorientation.