Rh-TPPTS/CTAB-MMT催化剂的制备及其催化长链烯烃氢甲酰化反应性能研究

通过浸渍法将水溶性铑膦配合物(Rh-TPPTS)负载到由十六烷基三甲基溴化铵(CTAB)修饰的蒙脱土(MMT)上,制备出Rh-TPPTS/CTAB-MMT负载型催化剂.采用XRD,FTIR,TG,BET,31P CP-MAS NMR和分散性实验对催化剂进行了表征.结果表明:水溶性铑膦配合物成功地负载到有机MMT上,并且该催化剂在有机溶剂中具有很好的分散性.该催化剂对于1-癸烯的氢甲酰化反应具有好的催化活性.在100℃、4 MPa、甲苯为溶剂的条件下,催化1-癸烯氢甲酰化可获得93.0%的转化率,95.8%的醛的选择性,2.1的正异比,137 h-1的TOF值.并对不同链长烯烃底物进行了考察.随着烯烃碳链的增加,醛的选择性下降,但是正异比有所增加.     

Effects of Doping and Oxygen Vacancy Concentrations on Oxygen Ion Migration in Sm_xCe_(1-x)O_(2-δ): a DFT + U Study

Influence of doping and oxygen vacancy concentrations on oxygen ion or oxygen vacancy(V) migration energies of Sm_xCe_(1-x)O_(2-δ)(x = 0.0625, 0.125, 0.25 and δ = 0.0625, 0.125) systems using a GGA+U method are studied. Calculated results show that advantage migration types change from V?O~(2-) to O~(2-) ?V as x and δ increase. For V?O~(2-) migrations of the Sm_(0.0625)Ce_(0.9375)O_(1.9375) and Sm_(0.125)Ce_(0.875)O_(1.9375) systems, electrostatic attractions between Sm~(3+) and V, defect associations between Ce~(3+) and V, and steric hindrances of Sm~(3+) affect the migration energies. For O~(2-) ?V migrations of the Sm+(0.125)Ce_(0.875)O_(1.875) and Sm_(0.25)Ce_(0.75)O_(1.875) systems, migration energies of O~(~(2-) ) are affected by electrostatic repulsions between Sm~(3+) and O~(2-) and defect associations between Ce~(3+) and V. Increases of the oxygen vacancy and Sm~(3+) doping concentrations benefit the oxygen ion and vacancy migrations, respectively.     

GC-MS法测定ABS木塑材料中十溴二苯醚

建立了索氏提取和超声萃取-GC-MS法测定丙烯腈-丁二烯-苯乙烯共聚物(ABS)木塑材料中十溴二苯醚的分析方法。通过正交试验分析提取溶剂、样品质量和提取时间三个因素的显著性,并优化了参数。在优化条件下,索氏提取和超声萃取法的平均回收率均大于80%,精密度均小于10%。经F检验和T检验显著性统计,两种前处理方法的精密度和准确度不存在差异。相对于传统的索氏提取法,超声萃取法具有操作简单、溶剂用量少和省时的特点,可以较好的应用于木塑材料中十溴二苯醚检测。