The pursuit of cleanliness,energy efficiency,and resource preservation through photochemical reactions has led to the emergence of novel pathways and methodologies in synthetic chemistry,rendering it one of the most d...The pursuit of cleanliness,energy efficiency,and resource preservation through photochemical reactions has led to the emergence of novel pathways and methodologies in synthetic chemistry,rendering it one of the most dynamic research domains within modern organic synthesis.Carbon dioxide(CO_(2)),owing to its non-toxic,cost-effective,abundant,and recyclable attributes,serves as an optimal C1 precursor in synthetic chemistry.Recent years have witnessed rapid advancements in the photochemical conversion of CO_(2) into carboxylic acid compounds,offering a gentle and highly efficient synthetic approach for their production.An overview of the research progress on the synthesis methodologies of carboxylic acid compounds through photochemical CO_(2) conversion is provided,while certain associated reaction mechanisms are also elucidated.展开更多
为了优化鹅肥肝及鹅肝酱中脂肪酸的检测方法,通过比较脂肪酸甲酯化的5种不同处理方法,得到了较优的样品处理方法。该方法为盐酸甲酯化,样品用15 mL氯仿∶甲醇(2∶1)提取脂肪,再用15 mL 1 mol/L KOH-乙醇皂化,在皂化物加入30 mL 4%盐酸-...为了优化鹅肥肝及鹅肝酱中脂肪酸的检测方法,通过比较脂肪酸甲酯化的5种不同处理方法,得到了较优的样品处理方法。该方法为盐酸甲酯化,样品用15 mL氯仿∶甲醇(2∶1)提取脂肪,再用15 mL 1 mol/L KOH-乙醇皂化,在皂化物加入30 mL 4%盐酸-甲醇溶液甲酯化,得到甲酯化样品。该方法甲酯化较完全,操作可行。展开更多
The paper reports the method for determination of Tartaric acid and Maleic acid by high performance liquid chromatography. Tartaric acid and Maleic acid were separated on a Shim-pack CLC ODS (150 mm×6. 0 mm id, 5...The paper reports the method for determination of Tartaric acid and Maleic acid by high performance liquid chromatography. Tartaric acid and Maleic acid were separated on a Shim-pack CLC ODS (150 mm×6. 0 mm id, 5 μm) column with 0. 01 mol/L NaH2PO4- H3PO4(pH= 2. 0) as mobile phase, and the flow rate was 0. 7 mL/min. The components detected at UV at 220 nm. The quantitative results were obtained by external standard on a method.展开更多
The natural rubber seed oil was extracted by The supercritical fluid CO2 technology. The contents of fatty acids in The natural rubber seed oil were determined by means of GC normalization. Its unknown components were...The natural rubber seed oil was extracted by The supercritical fluid CO2 technology. The contents of fatty acids in The natural rubber seed oil were determined by means of GC normalization. Its unknown components were tested and identified by The method of GC/MS. The rubber seed oil extracted by The Supercritical Fluid CO2(SFE- CO2) was compared with The one extracted by The method of Soxhlet. The results show that 12 kinds of fatty acids in The rubber seed were determined, and The contens of α-18:3 and γ-18.3, which have great value, were respectively 18.74% and 0.70%. The rubber seed oil extracted by SFE- CO2 has no organic solvent, and are nonpoisonous and harmless. Its GC graph is plain and has less miscellaneous peaks and The contents of γ-18:3 is 4 times more than that extracted by The method of Soxhlet. In addition, The fatty acid contents of ≥ 3 alkene bonds were significantly decreased after The sample of The fatty acid methyl ester was placed in a refrigerator more than 3 months.展开更多
文摘The pursuit of cleanliness,energy efficiency,and resource preservation through photochemical reactions has led to the emergence of novel pathways and methodologies in synthetic chemistry,rendering it one of the most dynamic research domains within modern organic synthesis.Carbon dioxide(CO_(2)),owing to its non-toxic,cost-effective,abundant,and recyclable attributes,serves as an optimal C1 precursor in synthetic chemistry.Recent years have witnessed rapid advancements in the photochemical conversion of CO_(2) into carboxylic acid compounds,offering a gentle and highly efficient synthetic approach for their production.An overview of the research progress on the synthesis methodologies of carboxylic acid compounds through photochemical CO_(2) conversion is provided,while certain associated reaction mechanisms are also elucidated.
文摘为了优化鹅肥肝及鹅肝酱中脂肪酸的检测方法,通过比较脂肪酸甲酯化的5种不同处理方法,得到了较优的样品处理方法。该方法为盐酸甲酯化,样品用15 mL氯仿∶甲醇(2∶1)提取脂肪,再用15 mL 1 mol/L KOH-乙醇皂化,在皂化物加入30 mL 4%盐酸-甲醇溶液甲酯化,得到甲酯化样品。该方法甲酯化较完全,操作可行。
文摘The paper reports the method for determination of Tartaric acid and Maleic acid by high performance liquid chromatography. Tartaric acid and Maleic acid were separated on a Shim-pack CLC ODS (150 mm×6. 0 mm id, 5 μm) column with 0. 01 mol/L NaH2PO4- H3PO4(pH= 2. 0) as mobile phase, and the flow rate was 0. 7 mL/min. The components detected at UV at 220 nm. The quantitative results were obtained by external standard on a method.
文摘The natural rubber seed oil was extracted by The supercritical fluid CO2 technology. The contents of fatty acids in The natural rubber seed oil were determined by means of GC normalization. Its unknown components were tested and identified by The method of GC/MS. The rubber seed oil extracted by The Supercritical Fluid CO2(SFE- CO2) was compared with The one extracted by The method of Soxhlet. The results show that 12 kinds of fatty acids in The rubber seed were determined, and The contens of α-18:3 and γ-18.3, which have great value, were respectively 18.74% and 0.70%. The rubber seed oil extracted by SFE- CO2 has no organic solvent, and are nonpoisonous and harmless. Its GC graph is plain and has less miscellaneous peaks and The contents of γ-18:3 is 4 times more than that extracted by The method of Soxhlet. In addition, The fatty acid contents of ≥ 3 alkene bonds were significantly decreased after The sample of The fatty acid methyl ester was placed in a refrigerator more than 3 months.
