Electrochemical Synthesis of Diamond in Molten LiCl-KCl-K₂CO₃-KOH

We propose a novel diamond synthesis method based on molten salt electrolysis. In our method, carbon deposition and hydrogen generation occur simultaneously, and hydrogen reacts selectively with carbon atoms that possess sp² hybrid orbitals to form CH₄ gas. Therefore, only carbon with sp³ hybrid orbitals grows to form a diamond. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Raman spectroscopy analysis confirmed that diamond was synthesized by potentiostatic electrolysis at 1.1 V vs Li⁺/Li with a 10 C cm⁻² charge density in molten LiCl–KCl–K₂CO₃–KOH at 973 K

Observation of a Dirac nodal line in AlB2

We have performed angle-resolved photoemission spectroscopy of AlB2 which is isostructural to high-temperature superconductor MgB2. Using soft-x-ray photons, we accurately determined the three-dimensional bulk band structure and found a highly anisotropic Dirac-cone band at the K point in the bulk hexagonal Brillouin zone. This band disperses downward on approaching the H point while keeping its degeneracy at the Dirac point, producing a characteristic Dirac nodal line along the KH line. We also found that the band structure of AlB2 is regarded as a heavily electron-doped version of MgB2 and is therefore well suited for fully visualizing the predicted Dirac nodal line. The present results suggest that (Al,Mg)B2 system is a promising platform for studying the interplay among Dirac nodal line, carrier doping, and possible topological superconducting properties.Comment: 6 pages, 3 figure

Polymorphisms of estrogen metabolism-related genes ESR1 , UGT2B17 , and UGT1A1 are not associated with osteoporosis in artificial menopausal Japanese women

Introduction : Bilateral salpingo-oophorectomy (BSO) is a risk factor for osteoporosis. Previous studies have reported an association between genetic polymorphisms and the risk of developing osteoporosis. However, the relationship between osteoporosis and genetic polymorphisms in Japanese women treated with BSO is not well understood. To improve the quality of life for post-BSO patients, it is important to determine the genetic factors that influence their risk for osteoporosis. The aim of this study was to investigate the association between gene variations of estrogen metabolism-related genes and osteoporosis in surgically menopausal patients, which may improve the quality of life for surgically menopausal patients. Material and methods : This study included 203 menopausal women treated with BSO because of gynecologic disorders. One hundred and twenty-six women with artificial (surgical) menopause, who had undergone BSO in the premenopausal period, were compared with 77 women with natural menopause, who had undergone BSO in the postmenopausal period. The women were tested for bone mineral density to diagnose osteoporosis. Polymorphisms of estrogen receptor 1 ( ESR1 ) and UDP-glucuronosyl transferase (UGT) genes UGT2B17 and UGT1A1 were analyzed, and their association with bone mass and osteoporosis was statistically evaluated. Results : No significant association was found between osteoporosis and polymorphisms in ESR1 , UGT2B17 , or UGT1A1 in both groups, suggesting that BSO might be a more significant physiological factor in influencing bone mass density compared to genetic variations. Conclusions : These results suggest that the ESR1 , UGT2B17 , and UGT1A1 polymorphisms are not genetic factors affecting osteoporosis in postmenopausal Japanese women

Dirac semimetal phase and switching of band inversion in XMg₂Bi₂ (X = Ba and Sr)

角度分解光電子分光と第一原理バンド計算とを組み合わせることで、三元化合物BaMg₂Bi₂が、結晶のC3対称性によって保護されたブリルアンゾーン中心付近で交差する単純なディラックバンドを持つトポロジカルディラック半金属であることを明らかにした。また、同じ結晶構造を持つSrMg₂Bi₂は、スピン−軌道相互作用の減少によりバンド反転がないことを特徴とする通常の絶縁体となっていることがわかった