Compression of Ice to 210 Gigapascals: Infrared Evidence for a Symmetric Hydrogen-Bonded Phase

Protonated and deuterated ices (H2O and D2O) compressed to a maximum pressure of 210 gigapascals at 85 to 300 kelvin exhibit a phase transition at 60 gigapascals in H2O ice (70 gigapascals in D2O ice) on the basis of their infrared reflectance spectra determined with synchrotron radiation. The transition is characterized by soft-mode behavior of the nu3 O-H or O-D stretch below the transition, followed by a hardening (positive pressure shift) above it. This behavior is interpreted as the transformation of ice phase VII to a structure with symmetric hydrogen bonds. The spectroscopic features of the phase persisted to the maximum pressures (210 gigapascals) of the measurements, although changes in vibrational mode coupling were observed at 150 to 160 gigapascals.     

CIDR和PMSG诱导东北梅花鹿同期发情的初步研究

应用阴道内孕酮释放装置 (CIDR)结合不同来源和不同剂量的PMSG处理 ,观察东北梅花鹿同期发情效果。 2 6只试验鹿分成 5组 ,将CIDR放置母鹿阴道内 15d后取出 ,肌注不同剂量 (10 0～ 5 0 0IU)孕马血清促性腺激素 ,放入带试情布的公鹿试情 ,持续观察 72h。结果表明 ,取出CIDR后试验鹿在 (33.3± 7.0 )h发情。其中含 10 0IUPMSG的“Folligon”处理的试验鹿同期发情率达 10 0 % ;国产PMSG处理的梅花鹿随着PMSG剂量的增加 ,发情率有增加的趋势 ,但各组间差异不显著 (χ2 检验P >0 .0 5 )。同时 ,不同剂量的PMSG处理没有显著影响CIDR取出后至发情时的平均时间长度。