A new type of zeolite La-USL (ultra stable zeolite L (zeolite USL) modified by La), which has superior activity, stability and selectivity in catalytic cracking of hydrocarbons and thus can be used as an active ca...A new type of zeolite La-USL (ultra stable zeolite L (zeolite USL) modified by La), which has superior activity, stability and selectivity in catalytic cracking of hydrocarbons and thus can be used as an active catalyst component, is reported in this paper. The zeolite L with relative crystallinity of above 90% was synthesized by the hydrothermal crystallization method under optimum conditions and characterized by means of XRD, NH3-TPD and isotherm adsorption techniques. The in-situ synthesized zeolite L with a SiO2/Al2O3 mole ratio of 5-6 was modified by cation ion exchange, hydrothermal dealumination and chemical modifications with La in order to prepare La-containing USL with a higher framework SiO2/Al2O3 mole ratio of 15-30. The modified zeolite La-USL was used as an active additive component of fluid catalytic cracking (FCC) catalyst and the resulting catalysts were evaluated by microactivity test (MAT) and fixed-fluidized bed (FFB) experiments using heavy oil as feedstock. The influence of La content in La- USL on cracking product distribution, gasoline group composition and research octane number (RON) was investigated. The results showed that when La content in La-USL was 0.8 wt%, the addition of the corresponding La-USL could result in a FCC catalyst that produced significant improvement in product distribution and gasoline quality.展开更多
目的探讨Mex3C-1对卡巴胆碱诱导的Fos表达的影响。方法将具有可持续表达人Mex3C-1序列的质粒pLV-CMV-Mex3C(OE)在HEK293T细胞中包装成慢病毒载体,同时制备非特异性对照(NC)CmiR0001-MR03的慢病毒载体,分别感染人神经母细胞瘤细胞SH-SY5Y...目的探讨Mex3C-1对卡巴胆碱诱导的Fos表达的影响。方法将具有可持续表达人Mex3C-1序列的质粒pLV-CMV-Mex3C(OE)在HEK293T细胞中包装成慢病毒载体,同时制备非特异性对照(NC)CmiR0001-MR03的慢病毒载体,分别感染人神经母细胞瘤细胞SH-SY5Y,经嘌呤霉素筛选后得到稳定高表达Mex3C-1和阴性对照细胞系,用Real time PCR和Western blot方法检测Mex3C-1的基因和蛋白表达效果。之后用卡巴胆碱诱导Fos表达,在诱导0、30、60、90和120min后分别提取mRNA,采用Real time PCR方法检测Fos mRNA的相对表达量。结果Real time PCR检测结果显示,OE组的Mex3C-1 mRNA的相对表达量(21.11±0.60)高于NC组(1.03±0.13)(t=32.63,P=0.000)。Western blot结果显示,在82kDa处OE组的Mex3C-1蛋白表达量高于NC组(P<0.001)。Real time PCR检测不同干预时间两组Fos mRNA,除0min外各个时间点OE组均高于NC组,表明Mex3C-1的过表达可以明显上调Fos mRNA的表达;NC组于120min时已基本恢复至基础值,而OE组120min时Fos mRNA表达量仍然较高,Mex3C-1过表达可以延长Fos mRNA的半衰期,增强其稳定性,OE组与阴性对照NC组比较,Fos mRNA表达量差异有统计学意义(F=287.069,P=0.000)。结论持续过表达Mex3C-1的人神经母细胞瘤SH-SY5Y细胞系建立成功,且Mex3C-1过表达能够明显增强卡巴胆碱诱导的Fos表达程度并增强其稳定性。展开更多
文摘A new type of zeolite La-USL (ultra stable zeolite L (zeolite USL) modified by La), which has superior activity, stability and selectivity in catalytic cracking of hydrocarbons and thus can be used as an active catalyst component, is reported in this paper. The zeolite L with relative crystallinity of above 90% was synthesized by the hydrothermal crystallization method under optimum conditions and characterized by means of XRD, NH3-TPD and isotherm adsorption techniques. The in-situ synthesized zeolite L with a SiO2/Al2O3 mole ratio of 5-6 was modified by cation ion exchange, hydrothermal dealumination and chemical modifications with La in order to prepare La-containing USL with a higher framework SiO2/Al2O3 mole ratio of 15-30. The modified zeolite La-USL was used as an active additive component of fluid catalytic cracking (FCC) catalyst and the resulting catalysts were evaluated by microactivity test (MAT) and fixed-fluidized bed (FFB) experiments using heavy oil as feedstock. The influence of La content in La- USL on cracking product distribution, gasoline group composition and research octane number (RON) was investigated. The results showed that when La content in La-USL was 0.8 wt%, the addition of the corresponding La-USL could result in a FCC catalyst that produced significant improvement in product distribution and gasoline quality.
文摘目的探讨Mex3C-1对卡巴胆碱诱导的Fos表达的影响。方法将具有可持续表达人Mex3C-1序列的质粒pLV-CMV-Mex3C(OE)在HEK293T细胞中包装成慢病毒载体,同时制备非特异性对照(NC)CmiR0001-MR03的慢病毒载体,分别感染人神经母细胞瘤细胞SH-SY5Y,经嘌呤霉素筛选后得到稳定高表达Mex3C-1和阴性对照细胞系,用Real time PCR和Western blot方法检测Mex3C-1的基因和蛋白表达效果。之后用卡巴胆碱诱导Fos表达,在诱导0、30、60、90和120min后分别提取mRNA,采用Real time PCR方法检测Fos mRNA的相对表达量。结果Real time PCR检测结果显示,OE组的Mex3C-1 mRNA的相对表达量(21.11±0.60)高于NC组(1.03±0.13)(t=32.63,P=0.000)。Western blot结果显示,在82kDa处OE组的Mex3C-1蛋白表达量高于NC组(P<0.001)。Real time PCR检测不同干预时间两组Fos mRNA,除0min外各个时间点OE组均高于NC组,表明Mex3C-1的过表达可以明显上调Fos mRNA的表达;NC组于120min时已基本恢复至基础值,而OE组120min时Fos mRNA表达量仍然较高,Mex3C-1过表达可以延长Fos mRNA的半衰期,增强其稳定性,OE组与阴性对照NC组比较,Fos mRNA表达量差异有统计学意义(F=287.069,P=0.000)。结论持续过表达Mex3C-1的人神经母细胞瘤SH-SY5Y细胞系建立成功,且Mex3C-1过表达能够明显增强卡巴胆碱诱导的Fos表达程度并增强其稳定性。