Phytochemical investigation of Lagotis yunnanensis led to the isolation and identification of a new iridoid glucoside 1, named as 10-O-(3,4-dimethoxy-(E)-cinnamoyl)aucubin. Its structure was elucidated by spectroscopi...Phytochemical investigation of Lagotis yunnanensis led to the isolation and identification of a new iridoid glucoside 1, named as 10-O-(3,4-dimethoxy-(E)-cinnamoyl)aucubin. Its structure was elucidated by spectroscopie methods.展开更多
Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectro...Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectroscopic evidents.展开更多
A new phytosterone named passionsterone 1 has been isolated from the roots of Passiflora wilsonii, along with the known compound 24R-ethyl-5 α-cholestane-3 β ,6 a -diol 2. The structure of passionsterone 1 was eluci...A new phytosterone named passionsterone 1 has been isolated from the roots of Passiflora wilsonii, along with the known compound 24R-ethyl-5 α-cholestane-3 β ,6 a -diol 2. The structure of passionsterone 1 was elucidated as 24R-ethyl-5 α -cholestane-3 β,6 α-diol-23-one by spectroscopic means.展开更多
Diacetyl derivative of hecogenin 1 was oxidized to unsaturated ketone 5 via allylicalcohol 3 when it reacted with dimethyldioxirane (DMDO). The structure of 3 was confirmed byX-ray crystal analysis and the highly regi...Diacetyl derivative of hecogenin 1 was oxidized to unsaturated ketone 5 via allylicalcohol 3 when it reacted with dimethyldioxirane (DMDO). The structure of 3 was confirmed byX-ray crystal analysis and the highly regioselectivity of DMDO to different olefin bonds was alsoobserved when diosgenin derivative 6 was treated with DMDO.展开更多
Two new flavonol glycosides (1 and 2) together with two known flavonoides (3 and 4), were isolated from the whole plant of Knoxia corymbosa willd. The structures of 1 and 2 were elucidated as kaempferol-7-O-α-L-arabi...Two new flavonol glycosides (1 and 2) together with two known flavonoides (3 and 4), were isolated from the whole plant of Knoxia corymbosa willd. The structures of 1 and 2 were elucidated as kaempferol-7-O-α-L-arabinosyl-3-O-β-D-6'-acetylglucopyranoside and kaempferol -7-O-α-L-arabinosyl-3-O-β-D-3',6'-diacetylglucopyranoside respectively.展开更多
A new catalyst for methanol synthesis, ZnO-promoted rhodium supported on carbon nanotubes, was developed. It was found that the Rh-ZnO/CNTs catalyst had high activity of 411.4 mg CH3OH/g/cat/h and selectivity of 96.7...A new catalyst for methanol synthesis, ZnO-promoted rhodium supported on carbon nanotubes, was developed. It was found that the Rh-ZnO/CNTs catalyst had high activity of 411.4 mg CH3OH/g/cat/h and selectivity of 96.7 % for methanol at 1 MPa and 523 K. The activity of this catalyst is much higher than that of NC 207 catalyst at the same reaction conditions. It was suggested that the multi-walled structure CNTs favored both the couple transfer of the proton and electron over the surface of the catalyst and the uptake of hydrogen which was favorable to methanol synthesis.展开更多
A highly versatile numerical code - the Regional Atmospheric Modeling System (RAMS) was used into the heat island simulation of an inland mega-city - Chongqing and Sichuan Basin, China. The entire horizontal calculati...A highly versatile numerical code - the Regional Atmospheric Modeling System (RAMS) was used into the heat island simulation of an inland mega-city - Chongqing and Sichuan Basin, China. The entire horizontal calculation domain 2000 km×2000 km and the vertical calculation domain was from 50cm under ground to the altitude of 15 000 m. The USGS (U.S.Geological Survey) topography and land use data, the NCEP (National Centers for Environmental Prediction) meteorological data were used as the input data of this simulation. The simulation shows that the temperature of Chongqing''s urban area was higher than that of suburb area corresponding to the topographical condition. It was confirmed that RAMS could be applied for the simulation of thermal environment. It was also demonstrated that the local climate in the smaller scale could be expressed by generating two-way interactive nesting grid.展开更多
文摘Phytochemical investigation of Lagotis yunnanensis led to the isolation and identification of a new iridoid glucoside 1, named as 10-O-(3,4-dimethoxy-(E)-cinnamoyl)aucubin. Its structure was elucidated by spectroscopie methods.
文摘Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectroscopic evidents.
文摘A new phytosterone named passionsterone 1 has been isolated from the roots of Passiflora wilsonii, along with the known compound 24R-ethyl-5 α-cholestane-3 β ,6 a -diol 2. The structure of passionsterone 1 was elucidated as 24R-ethyl-5 α -cholestane-3 β,6 α-diol-23-one by spectroscopic means.
文摘Diacetyl derivative of hecogenin 1 was oxidized to unsaturated ketone 5 via allylicalcohol 3 when it reacted with dimethyldioxirane (DMDO). The structure of 3 was confirmed byX-ray crystal analysis and the highly regioselectivity of DMDO to different olefin bonds was alsoobserved when diosgenin derivative 6 was treated with DMDO.
文摘Two new flavonol glycosides (1 and 2) together with two known flavonoides (3 and 4), were isolated from the whole plant of Knoxia corymbosa willd. The structures of 1 and 2 were elucidated as kaempferol-7-O-α-L-arabinosyl-3-O-β-D-6'-acetylglucopyranoside and kaempferol -7-O-α-L-arabinosyl-3-O-β-D-3',6'-diacetylglucopyranoside respectively.
基金supportd by the NNSF of China(#29773037)the NSF of Fujian province(#E9910001 and#E0010006).|
文摘A new catalyst for methanol synthesis, ZnO-promoted rhodium supported on carbon nanotubes, was developed. It was found that the Rh-ZnO/CNTs catalyst had high activity of 411.4 mg CH3OH/g/cat/h and selectivity of 96.7 % for methanol at 1 MPa and 523 K. The activity of this catalyst is much higher than that of NC 207 catalyst at the same reaction conditions. It was suggested that the multi-walled structure CNTs favored both the couple transfer of the proton and electron over the surface of the catalyst and the uptake of hydrogen which was favorable to methanol synthesis.
文摘A highly versatile numerical code - the Regional Atmospheric Modeling System (RAMS) was used into the heat island simulation of an inland mega-city - Chongqing and Sichuan Basin, China. The entire horizontal calculation domain 2000 km×2000 km and the vertical calculation domain was from 50cm under ground to the altitude of 15 000 m. The USGS (U.S.Geological Survey) topography and land use data, the NCEP (National Centers for Environmental Prediction) meteorological data were used as the input data of this simulation. The simulation shows that the temperature of Chongqing''s urban area was higher than that of suburb area corresponding to the topographical condition. It was confirmed that RAMS could be applied for the simulation of thermal environment. It was also demonstrated that the local climate in the smaller scale could be expressed by generating two-way interactive nesting grid.