介孔交联蒙脱土固体酸催化剂的结构与性能

采用溶胶凝胶法制备介孔钛交联蒙脱土，再采用SO₄^2-和CeO₂进行两次改性，然后以之为载体，制备铜基交联蒙脱土介孔固体酸催化剂。 催化剂的结构通过BET、XRD、TPR、Py-IR、FTIR、XPS和SEM等手段进行表征，并研究了它们在富氧条件下对丙烯选择还原NO的催化性能。结果表明，钛交联剂能很好地撑开蒙脱土的土层，形成良好的介孔结构，其孔径分布集中在3～7 nm，并且使制得的交联蒙脱土载体的比表面积明显增大；SO₄     

Study on the Conformation of Cyclodecapeptide Loloatin C with Obvious Antibiotic Activity

The conformation of cyclodecapeptide loloatin C with obvious antibiotic activity has been investigated in 2,2,2-trifluoroethanol/sodium acetate buffer solution and then characterized by Fr-IR, CD and NMR spectrum. The results of FT-IR show that there exists β-strand or β-tum secondary structure in the molecule. According to the CD spectrum, the helical turn is dominant but the β-turn structure also exists. Conformation of the whole molecule is probably a helical β-turn.The chemical shifts and coupling constants prove the existence of a β-structure in the regions of Val,Orn2 and Leu3. NOESY data and temperature gradients of amide protons suggest that the molecular conformation is a dumbbell-like structure with the waist located between ornithyl (position 2) and D-phenylalanyl (position 7) and β-turn on both ends.     

介孔固体超强酸催化剂的制备与结构表征

以累托土为基质,采用硅锆双组分交联剂和SO₄^2-改性的方法,研制交联粘土介孔固体超强酸(SO₄^2-/SiZrR),借助XRD, BET法,FT-IR, Hammett指示剂法,NH₃-TPD, Py-IR和DTA等现代分析测试方法,表征其结构.实验结果表明:500℃焙烧后,SO₄^2-/SiZrR的Hammett酸度函数H_o＜-11.93,最可几孔径分布在2.3 nm左右,具有超强酸性和介孔结构;其超强酸中心属于L酸中心,是主要的催化活性中心;硅锆双组分交联柱能使交联粘土的热稳定性提高,以累托土为基质的交联粘土比以蒙脱土为基质的交联粘土热稳定性高.     

固体超强酸催化剂ZrO2-Dy2O3/SO42--HZSM-5的制备及结构性能关系的研究

合成了分子筛复合超强酸催化剂ＺｒＯ２－Ｄｙ２Ｏ３／ＳＯ＾２－４－ＨＺＳＭ－５;以柠檬酸和正丁醇的酯化反应为探针,运用Ｈａｍｍｅｔｔ指示剂法、ＢＥＴ、ＸＲＤ和ＡＥＳ等方法,考察了催化剂的制备条件与结构性能的关系。结果表明,Ｄｙ２Ｏ３与ＺｒＯ２的质量比为０．０３：１时,催化剂性能较好;最适宜焙烧温度为５５０℃,在此温度下制得的催化剂具有较大的比表面积和较强的酸性,催化剂中的ＺｒＯ２以四方晶形存在,该催