다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

BoltzTraP. A code for calculating band-structure dependent quantities

日本物理学会誌及びJournal of the Physical Society of Japanの月刊について

Physical Review B

Herein we cover the key concepts in the field of thermoelectric materials research, present the current understanding, and show the latest developments. Current research is aimed at increasing the thermoelectric figure of merit (ZT) by maximizing the power factor and/or minimizing the thermal conductivity. Attempts at maximizing the power factor include the development of new materials, optimization of existing materials by doping, and the exploration of nanoscale materials. The minimization of the thermal conductivity can come through solid-solution alloying, use of materials with intrinsically low thermal conductivity, and nanostructuring. Herein we describe the most promising bulk materials with emphasis on results from the last decade. Single-phase bulk materials are discussed in terms of chemistry, crystal structure, physical properties, and optimization of thermoelectric performance. The new opportunities for enhanced performance bulk nanostructured composite materials are examined and a look into the not so distant future is attempted.

New and Old Concepts in Thermoelectric Materials

Low-temperature muon spin relaxation measurements on CeRu4Sn6

Photoinduced non-linear optical monitoring of novel semimagnetic semiconductors Pb1-xYbxX (X=S, Se, Te)

The low-temperature specific heat c p of the recently synthesized defect clathrate series Ba 8 - x Eu x Ge 43 □ 3 ( x = 0.3 , 0.6 ) strongly depends on the Eu content x. c p / T vs. temperature T shows an upturn below 5 K, the intensity of which has previously been shown to increase with x. From investigation of c p in magnetic fields up to 9 T in the temperature range from 30 to 350 mK we conclude that this upturn is caused by a Schottky contribution from the Eu 2 + ground state octet that is split due to the crystal electric field and the magnetic field on the Eu site.

Schottky anomaly in low-temperature specific heat of Ba8-xEuxGe43□3

The perspective of melt spinning–rapid quenching of a melt to produce nanocrystalline intermetallic clathrates is discussed, using main-group and transition-metal clathrates as examples. While melt spinning was originally developed for production of amorphous materials, our first experiments on melt spinning of clathrates revealed a surprisingly large grain growth rate, resulting in grain sizes of at least 1 μm. However, using the “confusion effect,” i.e., complicating the chemical composition of the material by increasing the number of constituent elements, we have succeeded in reducing the grain size to 200 nm. We present our scanning electron microscopy, transmission electron microscopy, and transport property investigations and discuss the effect of composition on grain size, as well as thermodynamic and kinetic aspects of clathrate crystallization.

https://www.tpbin.com/Uploads/Subjects/63d3e8de-6618-456f-bddb-28cdef553afd.pdf

Melt Spinning of Clathrates: Electron Microscopy Study and Effect of Composition on Grain Size

CeAuSb2 has previously been classified as an antiferromagnet with moderately enhanced electron masses. As the magnetic order is suppressed by a magnetic field, non-Fermi liquid behaviour has been shown to emerge, suggesting the presence of a quantum critical point (QCP). Within the ordered phase a metamagnetic transition was detected. Here we investigate the material by isothermal magnetization M(H), transverse magnetoresistivity ρt(H) and Hall resistivity ρH(H) measurements. We show that the metamagnetic transition splits into two first order transitions below 2 K. Pronounced anomalies in ρt(H) and ρH(H) are not only observed at the QCP and the metamagnetic transitions but also at a new characteristic field above the QCP.

Silke Paschen

Papers

Low-temperature muon spin relaxation measurements on CeRu4Sn6

Photoinduced non-linear optical monitoring of novel semimagnetic semiconductors Pb1-xYbxX (X=S, Se, Te)

Schottky anomaly in low-temperature specific heat of Ba8-xEuxGe43□3

Melt Spinning of Clathrates: Electron Microscopy Study and Effect of Composition on Grain Size

Temperature–field phase diagram of quantum critical CeAuSb2