The recent literature concerning the magnetocaloric effect (MCE) has been reviewed. The MCE properties have been compiled and correlations have been made comparing the behaviours of the different families of magnetic materials which exhibit large or unusual MCE values. These families include: the lanthanide (R) Laves phases (RM2, where M = Al, Co and Ni), Gd5(Si1−xGex)4 ,M n(As1−xSbx), MnFe(P1−xAsx), La(Fe13−xSix) and their hydrides and the manganites (R1−xMxMnO3, where R = lanthanide and M = Ca, Sr and Ba). The potential for use of these materials in magnetic refrigeration is discussed, including a comparison with Gd as a near room temperature active magnetic regenerator material. (Some figures in this article are in colour only in the electronic version)

https://iopscience.iop.org/article/10.1088/0034-4885/68/6/R04/pdf

Recent developments in magnetocaloric materials

Magnetocaloric effect: From materials research to refrigeration devices

Modern society relies on readily available refrigeration. Magnetic refrigeration has three prominent advantages compared with compressor-based refrigeration. First, there are no harmful gases involved; second, it may be built more compactly as the working material is a solid; and third, magnetic refrigerators generate much less noise. Recently a new class of magnetic refrigerant-materials for room-temperature applications was discovered. These new materials have important advantages over existing magnetic coolants: they exhibit a large magnetocaloric effect (MCE) in conjunction with a magnetic phase-transition of first order. This MCE is larger than that of Gd metal, which is used in the demonstration refrigerators built to explore the potential of this evolving technology. In the present review we compare the different materials considering both scientific aspects and industrial applicability. Because fundamental aspects of MCE are not so widely discussed, we also give some theoretical considerations.

https://iopscience.iop.org/article/10.1088/0022-3727/38/23/R01/pdf

Developments in magnetocaloric refrigeration

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1600-6143.2005.01081.x

Small-for-size syndrome after partial liver transplantation: definition, mechanisms of disease and clinical implications.

Theoretical aspects of the magnetocaloric effect

https://aasldpubs.onlinelibrary.wiley.com/doi/pdf/10.1002/lt.20317

Impact of portal venous pressure on regeneration and graft damage after living-donor liver transplantation.

Background. Previous studies have shown poor outcome after living-donor liver transplantation (LDLT) as a result of excessive portal venous pressure (PVP), excessive portal venous flow (PVF), or inadequate PVF. We investigated optimal portal venous circulation for liver graft function after LDLT in adult recipients retrospectively. Methods. Between June 2003 and November 2004, 28 adult patients underwent LDLT in our institution. We modulated PVP under 20 mmHg in these 28 cases by performing a splenectomy (n=4) or splenorenal shunt (n=1). The PVF and PVP were measured at the end of the operation. Compliance was calculated by dividing PVF by PVP. Results. PVF and compliance showed a significant inverse correlation with peak billirubin levels after LDLT (r = -0.63: r=-0.60, P<0.01), and with peak international normalized ratio after LDLT (r=-0.41: r= -0.51, P<0.05). Compliance was higher in right-lobe graft with middle hepatic vein cases (148 ± 27 ml/min/mmHg), and lower in left-lobe graft cases (119±50 ml/min/mmHg). Conclusions. Liver graft function was better when PVF and graft compliance were higher and PVP was maintained under 20 mmHg.

Optimal portal venous circulation for liver graft function after living-donor liver transplantation.

Magnetization of MnAs 1-x Sb x was measured as functions of temperature and magnetic field for 0 < x ≤ 0.4. The entropy change caused by a magnetic field, ΔS mag , was estimated on the basis of the Maxwell relation. The ΔS mag for 0 ≤ x ≤ 0.3 in a field change of 5 T reaches 25-30 J/K kg, which exceeds that of other materials by a factor of 2-4. The substitution of Sb for As can tune the Curie temperature between 230 K and 315 K without any significant reduction of ΔS mag , The large ΔS mag originates in a paramagnetic to ferromagnetic transition induced by a magnetic field. These results indicate that MnAs 1-x Sb x is a promising material for a working substance in magnetic refrigeration near room temperature.

Extremely Large Magnetic Entropy Change of MnAs1-xSbx near Room Temperature.

https://aasldpubs.onlinelibrary.wiley.com/doi/pdf/10.1002/lt.20713

Kentaro Taniguchi

Papers

Impact of portal venous pressure on regeneration and graft damage after living-donor liver transplantation.

Optimal portal venous circulation for liver graft function after living-donor liver transplantation.

Extremely Large Magnetic Entropy Change of MnAs1-xSbx near Room Temperature.

KICG value, a reliable real‐time estimator of graft function, accurately predicts outcomes in adult living‐donor liver transplantation

Improvement of morphological changes after 70% hepatectomy with portocaval shunt: preclinical study in porcine model.