Two eremophilane-type sesquiterpenoids from the rhizomes of Ligularia veitchiana（Hemsl.） Greenm were isolated and determined as 10α,11-endoperoxide-1（2）-en-7α-hydroeremophilane（1） and 1（10）-en-2-oxo-7α-isop...Two eremophilane-type sesquiterpenoids from the rhizomes of Ligularia veitchiana（Hemsl.） Greenm were isolated and determined as 10α,11-endoperoxide-1（2）-en-7α-hydroeremophilane（1） and 1（10）-en-2-oxo-7α-isopropanol-eremophilane（2）.Compound 1 was a new compound and compound 2 was a new natural product.The structures of the two compounds were established by means of spectral methods including 1^H NMR,13^C NMR,2D NMR and MS.展开更多
Artificial sunlight is a heat source in solar collector testing,where the light intensity and ambient conditions are controlled to provide uniformity in each test.In this study,twenty-five tungsten halogen lamps of 30...Artificial sunlight is a heat source in solar collector testing,where the light intensity and ambient conditions are controlled to provide uniformity in each test.In this study,twenty-five tungsten halogen lamps of 300 W 220 V were investigated for possible usage as the heat source.The experiment was conducted by varying the height of the lamps to the light field(H_(d)).The EN-12975-2 Standard was used to control the quality of the heat source on the light field.The results showed that the average light intensity(I_(avg))decreased with an increase in Hd.When H_(d) was low,the%uniformity values(%u_(xy))met the criteria.The small light field area met the EN-12975-2 Standard better than the large area.A comparison of solar collector testing under a heat source from tungsten halogen lamps and natural sunlight was subsequently performed,and the experimental results were in accordance with the EN-12975-2 Standard.A single-channel flat plate solar collector was used as the test device and air was used as the working fluid.The experimental results revealed that the solar collector thermal efficiency(η_(avg))trends were similar for both the heat source from tungsten halogen lamps and natural sunlight testing.A low%u_(xy) resulted in a𝜂avg that was more similar to that of natural sunlight.展开更多
文摘Two eremophilane-type sesquiterpenoids from the rhizomes of Ligularia veitchiana（Hemsl.） Greenm were isolated and determined as 10α,11-endoperoxide-1（2）-en-7α-hydroeremophilane（1） and 1（10）-en-2-oxo-7α-isopropanol-eremophilane（2）.Compound 1 was a new compound and compound 2 was a new natural product.The structures of the two compounds were established by means of spectral methods including 1^H NMR,13^C NMR,2D NMR and MS.
基金supported by Science Research and Innovation Fund.Contract No.FF66-P1-134.
文摘Artificial sunlight is a heat source in solar collector testing,where the light intensity and ambient conditions are controlled to provide uniformity in each test.In this study,twenty-five tungsten halogen lamps of 300 W 220 V were investigated for possible usage as the heat source.The experiment was conducted by varying the height of the lamps to the light field(H_(d)).The EN-12975-2 Standard was used to control the quality of the heat source on the light field.The results showed that the average light intensity(I_(avg))decreased with an increase in Hd.When H_(d) was low,the%uniformity values(%u_(xy))met the criteria.The small light field area met the EN-12975-2 Standard better than the large area.A comparison of solar collector testing under a heat source from tungsten halogen lamps and natural sunlight was subsequently performed,and the experimental results were in accordance with the EN-12975-2 Standard.A single-channel flat plate solar collector was used as the test device and air was used as the working fluid.The experimental results revealed that the solar collector thermal efficiency(η_(avg))trends were similar for both the heat source from tungsten halogen lamps and natural sunlight testing.A low%u_(xy) resulted in a𝜂avg that was more similar to that of natural sunlight.
