Magnetic Properties and Magnetocaloric Effect in Layered NdMn1.9Ti0.1Si2

The structural and magnetic properties of the NdMn1.9Ti0.1Si2 compund have been studied by high-intensity x-ray and high-resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range of 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9Ti0.1Si2 are indicated as TC ~ 22 K and TN ~ 374 K respectively. The first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc] around TC is found in layered NdMn1.9Ti0.1Si2and is associated with large magnetocaloric effect. This behavior has been confirmed as a contribution of the magnetostructural coupling by using neutron and x-ray powder diffraction. The magnetic entropy change –ΔSM ~ 15.3 J kg-1 K-1 and adiabatic temperature change ΔTad ~ 4.7 K have been determined using magnetization and specific heat measurement under 0-5 T applied fields. This compound exhibits almost no thermal and magnetic hysteresis, thus potentially applicable in low temperature region for magnetic refrigerator material.Received: 31 December 2013; Revised:10 February 2014; Accepted: 24 February 201

Magnetic Properties and Magnetocaloric Effect in Layered NdMn1.9Ti0.1Si2

The structural and magnetic properties of the NdMn1.9Ti0.1Si2 compund have been studied by high-intensity x-ray and high-resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range of 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9Ti0.1Si2 are indicated as TC ~ 22 K and TN ~ 374 K respectively. The first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc] around TC is found in layered NdMn1.9Ti0.1Si2and is associated with large magnetocaloric effect. This behavior has been confirmed as a contribution of the magnetostructural coupling by using neutron and x-ray powder diffraction. The magnetic entropy change –ΔSM ~ 15.3 J kg-1 K-1 and adiabatic temperature change ΔTad ~ 4.7 K have been determined using magnetization and specific heat measurement under 0-5 T applied fields. This compound exhibits almost no thermal and magnetic hysteresis, thus potentially applicable in low temperature region for magnetic refrigerator material.Received: 31 December 2013; Revised:10 February 2014; Accepted: 24 February 201

Magnetocaloric effect and magnetostructural coupling in Mn0.92Fe0.08CoGe compound

The structural properties of Mn0.92Fe0.08CoGe have been investigated in detail using synchrotron x-ray diffraction in zero and applied pressure (p = 0-10 GPa). A ferromagnetic transition occurs around TC = 300 K and a large magnetic-entropy change -ΔSM = 17.3 J/kg K detected at TC for a field change of ΔB = 5 T. The field dependence of -ΔSM max can be expressed as -ΔSM max ∞ B. At ambient temperature and pressure, Mn0.92Fe0.08CoGe exhibits a co-existence of the orthorhombic TiNiSi-type structure (space group Pnma) and hexagonal Ni2In-type structure (space group P63/mmc). Application of external pressure drives a structure change from the orthorhombic TiNiSi-type structure to the hexagonal Ni2In-type structure. A large anomaly in heat capacity around TC is detected and the Debye temperature θD (=319(±10) K) has been derived from analyses of the low temperature heat capacity, T ≲ 10 K

Comparative study on activation function based heart abnormality activity

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Dissolved Gas Analysis (DGA) of natural ester oils under arcing faults

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