Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N(1,7)-n-OPIMB and N(1,7)-n-SP1MB (n = 20, 22), respectively, were synth...Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N(1,7)-n-OPIMB and N(1,7)-n-SP1MB (n = 20, 22), respectively, were synthesized. The mesomorphic properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (XRD). Compared to the direct transition from the isotropic phase to the chiral B4 phase examined in N(1,7)-n-OPIMB, N(1,7)-n-SPIMB exhibited a rare Iso-Ncol-Colh-B4 phase sequence. The combination of the asymmetric low bent-angle 1,7-naphathalene central core and the flexible long alkylthio tail is considered to play an important role in the formation of such a novel phase sequence.展开更多
为了解脂尾绵羊的尾部性状特征,该试验选择滩羊典型生产区开展调查和试验观测,通过测量滩羊尾部尺寸、重量及尾骨特征,分析滩羊尾型特征及脂尾性状间的表型相关。结果显示:滩羊尾型可分为圆盘形尾、楔形尾和三角形尾3种;滩羊尾椎数量为1...为了解脂尾绵羊的尾部性状特征,该试验选择滩羊典型生产区开展调查和试验观测,通过测量滩羊尾部尺寸、重量及尾骨特征,分析滩羊尾型特征及脂尾性状间的表型相关。结果显示:滩羊尾型可分为圆盘形尾、楔形尾和三角形尾3种;滩羊尾椎数量为17~21枚不等:根据尾椎椎骨的完整程度,滩羊的尾椎可分为4类,第1类尾椎的横突、棘突、椎弓、椎孔完整,第2类尾椎的横突完整,棘突、椎弓、椎孔退化,第3类尾椎的横突、棘突、椎弓、椎孔均发生退化,第4类尾椎椎骨之间融合,无关节囊。滩羊尾重与尾厚,尾脂率与尾重及尾脂重之间相关性显著。滩羊尾重与尾长、尾厚之间的最优回归方程为:y=-2.237+0.401 x 3+0.041 x 1(R 2=0.634,P<0.01)。展开更多
基金supported by National Natural Science Foundation of China(No.51073007)
文摘Two homologous series of bent-shaped molecules composed of low bent-angle naphthalene central core and long alkoxy tail or alkylthio tail, N(1,7)-n-OPIMB and N(1,7)-n-SP1MB (n = 20, 22), respectively, were synthesized. The mesomorphic properties were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (XRD). Compared to the direct transition from the isotropic phase to the chiral B4 phase examined in N(1,7)-n-OPIMB, N(1,7)-n-SPIMB exhibited a rare Iso-Ncol-Colh-B4 phase sequence. The combination of the asymmetric low bent-angle 1,7-naphathalene central core and the flexible long alkylthio tail is considered to play an important role in the formation of such a novel phase sequence.
文摘为了解脂尾绵羊的尾部性状特征,该试验选择滩羊典型生产区开展调查和试验观测,通过测量滩羊尾部尺寸、重量及尾骨特征,分析滩羊尾型特征及脂尾性状间的表型相关。结果显示:滩羊尾型可分为圆盘形尾、楔形尾和三角形尾3种;滩羊尾椎数量为17~21枚不等:根据尾椎椎骨的完整程度,滩羊的尾椎可分为4类,第1类尾椎的横突、棘突、椎弓、椎孔完整,第2类尾椎的横突完整,棘突、椎弓、椎孔退化,第3类尾椎的横突、棘突、椎弓、椎孔均发生退化,第4类尾椎椎骨之间融合,无关节囊。滩羊尾重与尾厚,尾脂率与尾重及尾脂重之间相关性显著。滩羊尾重与尾长、尾厚之间的最优回归方程为:y=-2.237+0.401 x 3+0.041 x 1(R 2=0.634,P<0.01)。