A new flavonol glycoside, 5,7,3,4 tetrahydroxy 3 methoxyflavonol 3 O β D glucopyranoside(1) was isolated along with quercetin(2), quercetin 3 O α L rhamnopyranoside(3), quercetin 3 O β D ...A new flavonol glycoside, 5,7,3,4 tetrahydroxy 3 methoxyflavonol 3 O β D glucopyranoside(1) was isolated along with quercetin(2), quercetin 3 O α L rhamnopyranoside(3), quercetin 3 O β D glucopyranoside(4) and kaempferol 3 O β D (6' O p coumaroyl) glucopyranoside(5) from Anaphalis sinica Hance. Their structures were determined on the basis of spectral data(MS, UV, IR, 1H and 13 C NMR). The structure of compound 1 was confirmed by X ray crystallographic analysis.展开更多
In the stratosphere, CF3Cl（ CFC 13 ） can either photodecompose or react directly with atomic oxygen to generate ozone-depleting agents such as Cl and ClO in the gas phase. Since the 1970s, attention has been focused...In the stratosphere, CF3Cl（ CFC 13 ） can either photodecompose or react directly with atomic oxygen to generate ozone-depleting agents such as Cl and ClO in the gas phase. Since the 1970s, attention has been focused on the effects of these compounds on the destruction of ozone in the stratosphere and on global warming. Takahashi and coworkers detected ClO radicals and measured the product branching ratios of the title reaction system via the technique of vacuum ultraviolet laser-induced fluorescence. Yu and coworkers studied the mechanisms of the title reaction induced by the photolysis of the CF3Cl-O3 system at 253.7 nm.展开更多
We fabricated YBa2Cu3O7–d bulk ceramics with a domestic microwave oven and investigated the effect of pressure at the press procedure. If the pressure was not high enough, the ratio of BaCuO2 phase became large, esti...We fabricated YBa2Cu3O7–d bulk ceramics with a domestic microwave oven and investigated the effect of pressure at the press procedure. If the pressure was not high enough, the ratio of BaCuO2 phase became large, estimated from x-ray diffraction (XRD) measurements. We found that the pressure should be 700 kgf/cm2 at least in order to suppress the BaCuO2 phase.展开更多
基金Project (gf200901002) support by the National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology of Nanchang Hangkong University,China
文摘A new flavonol glycoside, 5,7,3,4 tetrahydroxy 3 methoxyflavonol 3 O β D glucopyranoside(1) was isolated along with quercetin(2), quercetin 3 O α L rhamnopyranoside(3), quercetin 3 O β D glucopyranoside(4) and kaempferol 3 O β D (6' O p coumaroyl) glucopyranoside(5) from Anaphalis sinica Hance. Their structures were determined on the basis of spectral data(MS, UV, IR, 1H and 13 C NMR). The structure of compound 1 was confirmed by X ray crystallographic analysis.
基金Supported by the National Natural Science Foundation of China(Nos. 20573064, 20073024) and the Special PhD Foundationof Ministry of Education of P. R. China(No. 20020422027).
文摘In the stratosphere, CF3Cl（ CFC 13 ） can either photodecompose or react directly with atomic oxygen to generate ozone-depleting agents such as Cl and ClO in the gas phase. Since the 1970s, attention has been focused on the effects of these compounds on the destruction of ozone in the stratosphere and on global warming. Takahashi and coworkers detected ClO radicals and measured the product branching ratios of the title reaction system via the technique of vacuum ultraviolet laser-induced fluorescence. Yu and coworkers studied the mechanisms of the title reaction induced by the photolysis of the CF3Cl-O3 system at 253.7 nm.
文摘We fabricated YBa2Cu3O7–d bulk ceramics with a domestic microwave oven and investigated the effect of pressure at the press procedure. If the pressure was not high enough, the ratio of BaCuO2 phase became large, estimated from x-ray diffraction (XRD) measurements. We found that the pressure should be 700 kgf/cm2 at least in order to suppress the BaCuO2 phase.
