Heat Capacity and Magnetization of Polycrystalline MnBr2·4H2O as a Function of Temperature at Magnetic Fields up to 30 000 G in the Liquid‐Helium Region

1970 ◽  
Vol 53 (3) ◽  
pp. 1031-1035 ◽  
Author(s):  
R. L. Stein ◽  
R. A. Butera
Keyword(s):  
Heat Capacity ◽  
Magnetic Fields ◽  
Liquid Helium

scholarly journals Теплоемкость и магнитокалорический эффект соединений LaFe-=SUB=-11.2-x-=/SUB=-Mn-=SUB=-x-=/SUB=-Co-=SUB=-0.7-=/SUB=-Si-=SUB=-1.1-=/SUB=- (x=0, 0.1, 0.2, 0.3)

2020 ◽  
Vol 62 (5) ◽  
pp. 752
Author(s):  
Н.З. Абдулкадирова ◽  
А.М. Алиев ◽  
А.Г. Гамзатов ◽  
P. Gebara
Keyword(s):  
Heat Capacity ◽  
Magnetic Fields ◽  
Curie Temperature ◽  
Specific Heat ◽  
Magnetocaloric Effect ◽  
Intermetallic Compounds ◽  
Indirect Method ◽  
Direct Method ◽  
Capacity Data ◽  
Value Changes

The specific heat and magnetocaloric effect of the LaFe11.2-хMnxCo0.7Si1.1 intermetallic compounds (x = 0.1, 0.2, 0.3) were measured in the temperature range 80–300 K and in magnetic fields up to 8 T. The magnetocaloric effect (MCE) was estimated using two methods: direct method in cyclic magnetic fields, as well as an indirect method from heat capacity data. It was shown that an increase in the concentration of Mn atoms leads to a shift in the Curie temperature of the TC toward lower temperatures, while the FM value changes slightly.

Imaging the Human Brain with Magnetoencephalography

2011 ◽  
pp. 881-889
Author(s):  
Dimitrios Pantazis
Keyword(s):  
Mathematical Modeling ◽  
Medical Imaging ◽  
Magnetic Fields ◽  
Human Brain ◽  
Electrical Activity ◽  
Liquid Helium ◽  
Communication Networks ◽  
Brain Function ◽  
Imaging Modality ◽  
Neuronal Disorders

Magnetoencephalography is a relatively new medical imaging modality for the monitoring and imaging of human brain function. Extracranial magnetic fields produced by the working human brain are measured by extremely sensitive superconducting sensors, called SQUIDs, enclosed in a liquid helium-filled dewar. Mathematical modeling allows the formation of images or maps of cortical neuronal currents that reveal neural electrical activity, identify cortical communication networks, and facilitate the treatment of neuronal disorders, such as epilepsy.

Imaging the Human Brain with Magnetoencephalography

2011 ◽  
pp. 294-302
Author(s):  
Dimitrios Pantazis ◽  
Richard M. Leahy
Keyword(s):  
Mathematical Modeling ◽  
Medical Imaging ◽  
Magnetic Fields ◽  
Human Brain ◽  
Electrical Activity ◽  
Liquid Helium ◽  
Communication Networks ◽  
Brain Function ◽  
Imaging Modality ◽  
Neuronal Disorders

Magnetoencephalography is a relatively new medical imaging modality for the monitoring and imaging of human brain function. Extracranial magnetic fields produced by the working human brain are measured by extremely sensitive superconducting sensors, called SQUIDs, enclosed in a liquid helium-filled dewar. Mathematical modeling allows the formation of images or  maps of cortical neuronal currents that reveal neural electrical activity, identify cortical communication networks, and facilitate the treatment of neuronal disorders, such as epilepsy.

scholarly journals Magnetic and Electronic Properties of π-d Interacting Molecular Magnetic Superconductor κ-(BETS)2FeX4 (X = Cl, Br) Studied by Angle-Resolved Heat Capacity Measurements

Crystals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 66 ◽  
Author(s):  
Shuhei Fukuoka ◽  
Sotarou Fukuchi ◽  
Hiroki Akutsu ◽  
Atsushi Kawamoto ◽  
Yasuhiro Nakazawa
Keyword(s):  
Magnetic Field ◽  
Heat Capacity ◽  
Magnetic Fields ◽  
Temperature Dependence ◽  
Three Dimensional ◽  
Magnetic Interaction ◽  
Spin Configuration ◽  
Magnetic Superconductor ◽  
Heat Capacity Measurements ◽  
Long Range Ordering

Thermodynamic picture induced by π-d interaction in a molecular magnetic superconductor κ-(BETS)2FeX4 (X = Cl, Br), where BETS is bis(ethylenedithio)tetraselenafulvalene, studied by single crystal calorimetry is reviewed. Although the S = 5/2 spins of Fe3+ in the anion layers form a three-dimensional long-range ordering with nearly full entropy of Rln6, a broad hump structure appears in the temperature dependence of the magnetic heat capacity only when the magnetic field is applied parallel to the a axis, which is considered as the magnetic easy axis. The scaling of the temperature dependence of the magnetic heat capacity of the two salts is possible using the parameter of |Jdd|/kB and therefore the origin of the hump structure is related to the direct magnetic interaction, Jdd, that is dominant in the system. Quite unusual crossover from a three-dimensional ordering to a one-dimensional magnet occurs when magnetic fields are applied parallel to the a axis. A notable anisotropic field-direction dependence against the in-plane magnetic field was also observed in the transition temperature of the bulk superconductivity by the angle-resolved heat capacity measurements. We discuss the origin of this in-plane anisotropy in terms of the 3d electron spin configuration change induced by magnetic fields.

Room Temperature Sample Scanning SQUID Microscope for Imaging the Magnetic Fields of Geological Specimens

2013 ◽  
Vol 475-476 ◽  
pp. 3-6 ◽  
Author(s):  
Qing Meng Wang ◽  
Hua Feng Qin ◽  
Qing Song Liu ◽  
Tao Song
Keyword(s):  
Magnetic Field ◽  
Low Temperature ◽  
Magnetic Fields ◽  
Liquid Helium ◽  
Quantum Interference ◽  
Three Dimensional ◽  
Input Circuit ◽  
Pickup Coil ◽  
Weak Magnetic Fields ◽  
Scanning Squid

A microscope to image weak magnetic fields using a low-temperature superconducting quantum interference device (SQUID) had developed with a liquid helium consumption rate of ~0.5L/hour. The gradient pickup coil is made by a low-temperature superconducting niobium wire with a diameter of 66 μm, which is coupled to the input circuit of the SQUID and is then enwound on the sapphire bobbin. Both of the pickup coil and the SQUID sensor are installed in a red copper cold finger, which is thermally anchored to the liquid helium evaporation platform in the vacuum space of the cryostat. To reduce the distance between the pickup coil and sample, a 100 μm thick sapphire window is nestled up to the bottom of the cryostat. A three-dimensional scanning stage platform with a 50 cm Teflon sample rack under the sapphire window had the precision of 10 μm. To test the fidelity of the new facility, the distribution of the magnetic field of basalt slice specimens was determined. Results show that the spatial resolution of the newly-designed facility is 500 μm with a gradient magnetic field sensitivity of 380fT. This opens new opportunities in examining the distribution of magnetic assemblages in samples, which bear great geological and geophysical information.

Entropy, Internal Energy, and Heat Capacity of MnCl2 between 0° and 4.2°K in Magnetic Fields to 100 kG

1965 ◽  
Vol 42 (3) ◽  
pp. 835-851 ◽  
Author(s):  
W. F. Giauque ◽  
E. W. Hornung ◽  
R. A. Fisher ◽  
G. E. Brodale
Keyword(s):  
Heat Capacity ◽  
Magnetic Fields ◽  
Internal Energy

Experimental apparatus for heat capacity measurements of 2D in magnetic fields

2003 ◽  
Vol 329-333 ◽  
pp. 146-147 ◽  
Author(s):  
Y. Matsumoto ◽  
S. Murakawa ◽  
K. Honkura ◽  
C. Bäuerle ◽  
H. Kambara ◽  
...  
Keyword(s):  
Heat Capacity ◽  
Magnetic Fields ◽  
Experimental Apparatus ◽  
Heat Capacity Measurements
Sign in / Sign up

Export Citation Format

Share Document