Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) w...Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) were prepared from N,N dimethylforamide (dmf) solution of Ce(NO 3) 3. Their thermal stability, optical properties and coordination features were investigated with thermogravimetric and differential thermal analysis, ultraviolet and visible spectrophotometer, fluorescence spectrophotometer, infrared spectroscopy, and 1H NMR spectrometer. In the solvents of C 6H 6, 1,2 dichloroethane and dmf, complexes A and B can exhibit a ligand to metal charge transfer transition lying in ca. 20000 cm -1 in the electronic spectra. Complex A displays a dimeric structure in C 6D 6 solution. Ce 4+ ions in the complexes are coordinated by phenolic groups of the ligands, oxygen atoms of dmf molecules, and / or OH - ions.展开更多
On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-but...On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-butyl-4'-hydroxy-phenyl)-ethyloxy-p-cresole is produced as result of a structure transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one in a solid phase at room temperature except a single crystal at transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one a new substance is formed too. Spectrums 1Н and 13С NMR differ from similar spectrums of initial compound and the single crystal. New substance represents an admixture of isomeric compounds, capable reversible to be transformed in initial 5,7-di-tert-butylspiro(2,5) octa-4,7-diene-6-one and 2-(3’, 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole.展开更多
建立了用HPLC测定丙烯酸丁酯废水中对甲基苯磺酸的方法。采用C18色谱柱,以甲醇+磷酸二氢铵水溶液为流动相,流量为1.0 m L/min,检测波长为221 nm。采用外标法定量,相关系数为0.999 9。实际检测中,丙烯酸丁酯废水中的对甲基苯磺酸可与其...建立了用HPLC测定丙烯酸丁酯废水中对甲基苯磺酸的方法。采用C18色谱柱,以甲醇+磷酸二氢铵水溶液为流动相,流量为1.0 m L/min,检测波长为221 nm。采用外标法定量,相关系数为0.999 9。实际检测中,丙烯酸丁酯废水中的对甲基苯磺酸可与其他物质完全分离。方法相对标准偏差为1.28%,加标回收率为98.1%-102.2%。本方法简单、快速、准确,适用于丙烯酸丁酯工艺废水中对甲基苯磺酸含量的分析检测。展开更多
文摘Three Ce 4+ complexes Ce(p tert butylcalixarene)·(dmf) 4·H 2O (complex A), Ce(p tert butylcalixarene) 2·(dmf) 10 (complex B) and Ce(p tert butylcalixarene)·(dmf) 4 (complex C) were prepared from N,N dimethylforamide (dmf) solution of Ce(NO 3) 3. Their thermal stability, optical properties and coordination features were investigated with thermogravimetric and differential thermal analysis, ultraviolet and visible spectrophotometer, fluorescence spectrophotometer, infrared spectroscopy, and 1H NMR spectrometer. In the solvents of C 6H 6, 1,2 dichloroethane and dmf, complexes A and B can exhibit a ligand to metal charge transfer transition lying in ca. 20000 cm -1 in the electronic spectra. Complex A displays a dimeric structure in C 6D 6 solution. Ce 4+ ions in the complexes are coordinated by phenolic groups of the ligands, oxygen atoms of dmf molecules, and / or OH - ions.
文摘On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-butyl-4'-hydroxy-phenyl)-ethyloxy-p-cresole is produced as result of a structure transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one in a solid phase at room temperature except a single crystal at transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one a new substance is formed too. Spectrums 1Н and 13С NMR differ from similar spectrums of initial compound and the single crystal. New substance represents an admixture of isomeric compounds, capable reversible to be transformed in initial 5,7-di-tert-butylspiro(2,5) octa-4,7-diene-6-one and 2-(3’, 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole.
文摘建立了用HPLC测定丙烯酸丁酯废水中对甲基苯磺酸的方法。采用C18色谱柱,以甲醇+磷酸二氢铵水溶液为流动相,流量为1.0 m L/min,检测波长为221 nm。采用外标法定量,相关系数为0.999 9。实际检测中,丙烯酸丁酯废水中的对甲基苯磺酸可与其他物质完全分离。方法相对标准偏差为1.28%,加标回收率为98.1%-102.2%。本方法简单、快速、准确,适用于丙烯酸丁酯工艺废水中对甲基苯磺酸含量的分析检测。