RAMAN SCATTERING OF Dy/Y RARE EARTH SUPERLATTICE

We report the observations of Raman scattering of the TO phonon modes from the different layers in Dy/Y rare earth superlattices. It is found that helical phase lock-in transition at about 50 K in the Dy/Y superlattice is accompanied by the softening of TO phonons from both Dy magnetic layers and Y nonmagnetic layers.     

RAMAN SCATTERING OF α-ET3(ReO4)2 CHARGE-TRANSFER SALT

We describe the results of Haman studies on C=C stretch modes in α-ET₃(ReO₄)₂ charge-transfer salt with the incident laser beam polarised perpendicular and parallel to the large flat face of plate-like crystal. We have assigned central C=C stretch mode at 1454 cm^-1 and ring C=C stretch mode at 1470cm^-1. The change in ring C=C stretch vibration was observed at the metal-insulator transition of α-ET₃(ReO₄)₂ on warming due to the distortion of the ET molecules.     

Co－W－C固溶体比矫顽磁力

模拟硬质合金Ｃｏ基胶结相的成分制备了二元Ｃｏ－Ｗ、Ｃｏ－Ｃ固溶体和三元Ｃｏ－Ｗ－Ｃ固溶体模拟合金，探讨了固溶成分影响比矫顽磁力Ｈｓｃ的规律．结果表明，Ｗ和Ｃ的固溶可分别提高和降低其Ｈｓｃ，影响程度随固溶度增加而加剧；由于Ｃ对Ｈｓｃ的影响较Ｗ更为强烈，导致Ｃｏ－Ｗ－Ｃ固溶体模拟合金的Ｈｓｃ低于纯Ｃｏ．     

RAMAN SCATTERING OF α-ET3(ReO4)2 CHARGE-TRANSFER SALT

We describe the results of Haman studies on C=C stretch modes in α-ET₃(ReO₄)₂ charge-transfer salt with the incident laser beam polarised perpendicular and parallel to the large flat face of plate-like crystal. We have assigned central C=C stretch mode at 1454 cm^-1 and ring C=C stretch mode at 1470cm^-1. The change in ring C=C stretch vibration was observed at the metal-insulator transition of α-ET₃(ReO₄)₂ on warming due to the distortion of the ET molecules.     

RAMAN SCATTERING OF ORGANIC CHARGE-TRANSFER SALTS CONTAINING BEDT-TTF CATION

Raman scattering of several organic charge-transfer salts containing BEDT-TTF of ET cation such as κ-ET₂Cu(NCS)₂, β_L-ET₂I₃, α-ET₃Cl₂. 2H₂O, a-ET₃ (ReO₄)₂ and ETFeBr4 were measured and the variations of the frequencies of C=C bonds of ET molecules on charge transfer were observed. It is found that the energy of C=C stretch modes shows a general downward shift upon ionisation of ET molecule. In addition, we have observed the Raman spectra of C=C stretch vibratinns in κ-ET₂Cu(NCS)₂ single crystal on going through T_c(～10.4 K) and found no detectable effect during the superconducting phase transition.     

产学研合作的本质是合作创新

毫无疑问，产学研合作是提升企业技术创新能力的重要途径。如何有效开展产学研合作。既是时下怀着从低端制造业向高科技产业攀升这一光荣梦想的中国企业界迫切希望求解的问题，也是一直以来致力于创新提升竞争力的各级政府始终关注的话题。 本期“技术管理沙龙”的嘉宾们围绕着产学研合作，结合自身实践，畅谈认识和感受，其间闪烁着真知灼见。现采撷如下，供读者把味、镜鉴。