With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex...With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.展开更多
A two-step approach was reported to fabricate cobaltous hydroxide/y- nickel oxide hydroxide/reduced graphene oxide (Co(OH)217-NiOOHIRGO) nanocompo- sites on nickel foam by combining the reduction of graphene oxide...A two-step approach was reported to fabricate cobaltous hydroxide/y- nickel oxide hydroxide/reduced graphene oxide (Co(OH)217-NiOOHIRGO) nanocompo- sites on nickel foam by combining the reduction of graphene oxide with the help of refux condensation and the subsequent hydrothermal of Co(OH)2 on RGO. The microstructural, surface morphology and electrochemical properties of the Co(OH)2/γ-NiOOH/RGO nanocomposite were investigated. The results showed that the surface of the first-step fabricated γ-NiOOH/RGO nanocomposites was uniformly coated by Co(OH)2 nanoflakes with lateral size of tens of nm and thickness of several nm. Co(OH)2/γ-NiOOHIRGO nanocomposite demonstrated a high specific capacitance (745 mF/cm= at 0.5 mAJcm2) and a cycling stability of 69.8% after 1000 cycles at 30 mV/cm2· γ-NiOOH/RGO//Co(OH)2/γ- NiOOH/RGO asymmetric supercapacitor was assembled, and maximum gravimetric energy density of 57.3 W.h/kg and power density of 66.1 kW/kg were achieved. The synergistic effect between the highly conductive graphene and the nanoflake Co(OH)2 structure was responsible for the high electrochemical performance of the hybrid electrode. It is expected that this research could offer a simple method to prepare graphene-based electrode materials.展开更多
The condensation heat transfer in the inclined reflux condensers is investigated at various inclinations. A condensation heat transfer model is set up. The calculated values of the model agree well with the experiment...The condensation heat transfer in the inclined reflux condensers is investigated at various inclinations. A condensation heat transfer model is set up. The calculated values of the model agree well with the experimental data. Both the experimental data and the theoretical calculations show that the condensation heat transfer coefficient in the inclined reflux condensers varies with the inclinations and will be maximum when the inclination angle is about 10°.展开更多
基金Supported by Hunan Provincial University Innovation Platform Open Fund Project(19K049)。
文摘With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.
基金This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 51605293 and 51702213) and the Natural Science Foundation of Shanghai (16ZR1423500). The authors also acknowledge financial support from the Program for Associate Professor of Special Appointment (Young Eastern Scholar) at Shanghai Institutions of Higher Learning (QD2016013).
文摘A two-step approach was reported to fabricate cobaltous hydroxide/y- nickel oxide hydroxide/reduced graphene oxide (Co(OH)217-NiOOHIRGO) nanocompo- sites on nickel foam by combining the reduction of graphene oxide with the help of refux condensation and the subsequent hydrothermal of Co(OH)2 on RGO. The microstructural, surface morphology and electrochemical properties of the Co(OH)2/γ-NiOOH/RGO nanocomposite were investigated. The results showed that the surface of the first-step fabricated γ-NiOOH/RGO nanocomposites was uniformly coated by Co(OH)2 nanoflakes with lateral size of tens of nm and thickness of several nm. Co(OH)2/γ-NiOOHIRGO nanocomposite demonstrated a high specific capacitance (745 mF/cm= at 0.5 mAJcm2) and a cycling stability of 69.8% after 1000 cycles at 30 mV/cm2· γ-NiOOH/RGO//Co(OH)2/γ- NiOOH/RGO asymmetric supercapacitor was assembled, and maximum gravimetric energy density of 57.3 W.h/kg and power density of 66.1 kW/kg were achieved. The synergistic effect between the highly conductive graphene and the nanoflake Co(OH)2 structure was responsible for the high electrochemical performance of the hybrid electrode. It is expected that this research could offer a simple method to prepare graphene-based electrode materials.
基金This work was supportd by National Natural Science Foundation of China.
文摘The condensation heat transfer in the inclined reflux condensers is investigated at various inclinations. A condensation heat transfer model is set up. The calculated values of the model agree well with the experimental data. Both the experimental data and the theoretical calculations show that the condensation heat transfer coefficient in the inclined reflux condensers varies with the inclinations and will be maximum when the inclination angle is about 10°.