基于SBS改性剂和聚氨酯前驱体化学改性剂(polyurethane⁃precursor chemical modifier,PRM)潜在的物理化学空间交联特性,制备了SBS‒PRM复合改性沥青。通过三大指标(针入度、软化点、延度)、动力黏度明确复合改性沥青的高黏特征;采用频率...基于SBS改性剂和聚氨酯前驱体化学改性剂(polyurethane⁃precursor chemical modifier,PRM)潜在的物理化学空间交联特性,制备了SBS‒PRM复合改性沥青。通过三大指标(针入度、软化点、延度)、动力黏度明确复合改性沥青的高黏特征;采用频率扫描试验、多应力蠕变恢复试验、线性振幅扫描试验以及弯曲梁流变试验研究了改性沥青的流变特性;利用傅里叶变换红外光谱、原子力显微镜和荧光显微镜解释了SBS‒PRM物理化学复合改性机理;最后验证了沥青混合料性能。结果表明,PRM通过化学反应改变了沥青分子结构并提升SBS与沥青的相容性,形成了空间交联结构增强沥青的黏度、抵抗高温永久变形、低温开裂和疲劳破坏的性能;利用SBS‒PRM复合改性沥青制备的SMA‒13混合料具有良好的高温抗车辙、低温抗裂、抗水损性能。展开更多
UV analytical method for the extraction liquid of the steroidal saponin from chinese medicine rhizoma paridis has been established by using the chemical subspace invariant to linear transformation method and the chara...UV analytical method for the extraction liquid of the steroidal saponin from chinese medicine rhizoma paridis has been established by using the chemical subspace invariant to linear transformation method and the characteristics of the UV spectra.Based on the orthogonal test of L16(45),the five factors for the extraction of steroidal saponin from Yunnan rhizoma paridis,including the extraction time,the concentration of ethanol solution and its volumn,the time of heating reflux and the times of extraction,have been optimized according to the extraction ratio.The extraction ratio for the optimized extraction is up to 11.49%.It also has been proved that the time of heating reflux is the most important factor.展开更多
文摘基于SBS改性剂和聚氨酯前驱体化学改性剂(polyurethane⁃precursor chemical modifier,PRM)潜在的物理化学空间交联特性,制备了SBS‒PRM复合改性沥青。通过三大指标(针入度、软化点、延度)、动力黏度明确复合改性沥青的高黏特征;采用频率扫描试验、多应力蠕变恢复试验、线性振幅扫描试验以及弯曲梁流变试验研究了改性沥青的流变特性;利用傅里叶变换红外光谱、原子力显微镜和荧光显微镜解释了SBS‒PRM物理化学复合改性机理;最后验证了沥青混合料性能。结果表明,PRM通过化学反应改变了沥青分子结构并提升SBS与沥青的相容性,形成了空间交联结构增强沥青的黏度、抵抗高温永久变形、低温开裂和疲劳破坏的性能;利用SBS‒PRM复合改性沥青制备的SMA‒13混合料具有良好的高温抗车辙、低温抗裂、抗水损性能。
文摘UV analytical method for the extraction liquid of the steroidal saponin from chinese medicine rhizoma paridis has been established by using the chemical subspace invariant to linear transformation method and the characteristics of the UV spectra.Based on the orthogonal test of L16(45),the five factors for the extraction of steroidal saponin from Yunnan rhizoma paridis,including the extraction time,the concentration of ethanol solution and its volumn,the time of heating reflux and the times of extraction,have been optimized according to the extraction ratio.The extraction ratio for the optimized extraction is up to 11.49%.It also has been proved that the time of heating reflux is the most important factor.
