Abstract： To investigate the chemical constituents of the roots of Polygala wattersii Hance, the separation and purification were performed by solvent extraction and repeated column chromatography （CC） on silica ge...Abstract： To investigate the chemical constituents of the roots of Polygala wattersii Hance, the separation and purification were performed by solvent extraction and repeated column chromatography （CC） on silica gel, Sephadex LH-20 and macroporous resin D101, preparative TLC and semi-preparative HPLC. The structures were identified by spectroscopic analysis and comparison of their 1H and 13C NMR data with those reported in literatures. Twenty-three known compounds, including eleven xanthones （1-11）, nine sugar esters （12-20）, two triterpenoid saponins （21 and 22） and one phenylpropanoid （23） were isolated and their structures were identified as 1,3-dihydroxyxanthone （1）, 1-hydroxy-3-methoxyxanthone （2）, 1,3-dihydroxy-2-methoxyxanthone （3）, 1,3,7-trihydroxy-2- methoxyxanthone （4）, 1,3,6-trihydroxy-2,7-dimethoxyxanthone （5）, 1,6,7-trihydroxy-2,3-dimethoxyxanthone （6）, 1,7-dihydroxy- 2,3-methylenedioxyxanthone （7）, 1,7-dimethoxyxanthone （8）, 1,2,3-trimethoxyxanthone （9）, 1-methoxy-2,3-methylenedioxyxanthone （10）, 6-hydroxy-0-methoxy-2,3-methylenedioxyxanthone （11）, 3＇-O-feruloyl-6-O-acetyl sucrose （12）, arillatose B （13）, sibricose A5 （14）, sibricose A6 （15）, 3＇,6-di-O-sinapoyl sucrose （16）, tenufoliside A （17）, 3＇-O-3,4,5-trimethoxycinnamoyl-6-O-p-methoxybenzoyl sucrose （18）, glomeratose A （19）, 1-O-p-coumaroyl-D-glucopyranose （20）, bayogenin-3-O-glucoside （21）, tenufolin （22）, and sinapic acid （23）. Among them, compounds 2 and 12 were obtained from genus Polygala for the first time, and except compound 16, all others were isolated from this species for the first time.展开更多
一本杂志上刊登过如下一道题目: 题一:设,f（x）=（x<sup>2</sup>-4）<sup>1/2</sup>（x≤-2）.（1）求f<sup>-1</sup>（x）;（2）设a<sub>1</sub>=1,a<sub>n</sub>=f<...一本杂志上刊登过如下一道题目: 题一:设,f（x）=（x<sup>2</sup>-4）<sup>1/2</sup>（x≤-2）.（1）求f<sup>-1</sup>（x）;（2）设a<sub>1</sub>=1,a<sub>n</sub>=f<sup>-1</sup>(a<sub>n-1</sub>)（n≥2,n∈N）,求a<sub>n</sub>;（3）求sum from i=1 to n 1/（a<sub>1</sub>+a<sub>i</sub>+1）的值该题作为函数与数列的综合题在教学中广为流传,通常简解如下解:（1）函数,f（x）=（x<sup>2</sup>-4）<sup>1/2</sup>（定义域为x≤—2,值域为y≥0）的反函数为f<sup>-1</sup>（x）=-（x<sup>2</sup>+4）<sup>1/2</sup>（定义域为x≥0,值域为y≤-2） （2）∵a<sub>1</sub>=1,a<sub>n</sub>=f<sup>-1</sup>(a<sub>n-1</sub>)由迭代法得:a<sub>n</sub>=-(a<sub>n-1</sub><sup>2</sup>+4)<sup>1/2</sup>=-(a<sub>n-2</sub><sup>2</sup>+2×4)<sup>1/2</sup>=…=-（a<sub>1</sub><sup>2</sup>+（n-1）4）<sup>1/2</sup>=-（4n-3）<sup>1/2</sup>(亦可由a<sub>n</sub><sup>2</sup>=a<sub>n-1</sub><sup>2</sup>+4,n=2,3,…n,累加而得) （3） 注意到 a<sub>n</sub><sup>2</sup>-a<sub>n-1</sub><sup>2</sup>=4,展开更多
Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. ...Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. Their structures were determined by spectroscopic analysis and identified as quercetin （1）, quercetin 7-O-α-L-rhamnoside （2）, quercetin 3-O-α-L- rhamnoside （3）, 3-O-methyl quercetin （4）, 1,5-dihydroxyxanthone （5）, 1,5-dihydroxyxanthone-6-O-β-D-glucoside （6）, 5-hydroxy- l-methoxyxanthone （7） and 6-deoxyisojacareubin （8）. All these compounds were isolated from this title plant for the first time, and compounds 5-8 were obtained from genus Arenaria for the first time.展开更多
A series of material ejections associated with flares are observed in AR 5395 during 8 to 19 March, 1989. five events selected are repoted in this paper.
[Objective] The aim was to understand the species composition, distribution, density, seasonal fluctuation and pathogens of mosquitoes in four regions of East China to provide basic data for prevention and control of ...[Objective] The aim was to understand the species composition, distribution, density, seasonal fluctuation and pathogens of mosquitoes in four regions of East China to provide basic data for prevention and control of mosquitoes at ports. [Method] The mosquitoes at 21 ports of four regions in East China were investigated during 2011-2014 by CO2 lamp method, egg collection method, scoop method and visual method. The species of mosquitoes was identified, and pathogens in mosquitoes were detected. [Result] From 2011 to 2014, 102 583 mosquitoes were captured at the ports, belonging to 18 species, 6 genera and 1 family. Culex pipi- ens quinquefasciatus or Culex pipiens pallens was the dominant species at most ports. Mosquitoes could be captured from May to October, and the captured mosquitoes were the most in June. The positive rate of egg collectors was 9.41%, and the positive rate of breeding places was 7.23%. Rare entry mosquitoes were captured, and most of them were C. pipiens pallens. The detection results of dengue fever, malaria and other pathogens were negative. [Conclusion] C. pipiens quinquefasciatus or C. pipiens pallens was dominant at most ports, and the peak period was June. There were breeding environments of mosquitoes at some ports, so the prevention and control of mosquitoes at these ports should be paid more at- tention to in future.展开更多
基金The National Key Technology R&D Program"New Drug Innovation"of China(Grant No.2012ZX09301002-002-002,2012ZX09304-005)special funds for scientific research on traditional Chinese medicine(Grant No.201307002)National Science Fund for Excellent Young Scholars(Grant No.81222051)
文摘Abstract： To investigate the chemical constituents of the roots of Polygala wattersii Hance, the separation and purification were performed by solvent extraction and repeated column chromatography （CC） on silica gel, Sephadex LH-20 and macroporous resin D101, preparative TLC and semi-preparative HPLC. The structures were identified by spectroscopic analysis and comparison of their 1H and 13C NMR data with those reported in literatures. Twenty-three known compounds, including eleven xanthones （1-11）, nine sugar esters （12-20）, two triterpenoid saponins （21 and 22） and one phenylpropanoid （23） were isolated and their structures were identified as 1,3-dihydroxyxanthone （1）, 1-hydroxy-3-methoxyxanthone （2）, 1,3-dihydroxy-2-methoxyxanthone （3）, 1,3,7-trihydroxy-2- methoxyxanthone （4）, 1,3,6-trihydroxy-2,7-dimethoxyxanthone （5）, 1,6,7-trihydroxy-2,3-dimethoxyxanthone （6）, 1,7-dihydroxy- 2,3-methylenedioxyxanthone （7）, 1,7-dimethoxyxanthone （8）, 1,2,3-trimethoxyxanthone （9）, 1-methoxy-2,3-methylenedioxyxanthone （10）, 6-hydroxy-0-methoxy-2,3-methylenedioxyxanthone （11）, 3＇-O-feruloyl-6-O-acetyl sucrose （12）, arillatose B （13）, sibricose A5 （14）, sibricose A6 （15）, 3＇,6-di-O-sinapoyl sucrose （16）, tenufoliside A （17）, 3＇-O-3,4,5-trimethoxycinnamoyl-6-O-p-methoxybenzoyl sucrose （18）, glomeratose A （19）, 1-O-p-coumaroyl-D-glucopyranose （20）, bayogenin-3-O-glucoside （21）, tenufolin （22）, and sinapic acid （23）. Among them, compounds 2 and 12 were obtained from genus Polygala for the first time, and except compound 16, all others were isolated from this species for the first time.
文摘一本杂志上刊登过如下一道题目: 题一:设,f（x）=（x<sup>2</sup>-4）<sup>1/2</sup>（x≤-2）.（1）求f<sup>-1</sup>（x）;（2）设a<sub>1</sub>=1,a<sub>n</sub>=f<sup>-1</sup>(a<sub>n-1</sub>)（n≥2,n∈N）,求a<sub>n</sub>;（3）求sum from i=1 to n 1/（a<sub>1</sub>+a<sub>i</sub>+1）的值该题作为函数与数列的综合题在教学中广为流传,通常简解如下解:（1）函数,f（x）=（x<sup>2</sup>-4）<sup>1/2</sup>（定义域为x≤—2,值域为y≥0）的反函数为f<sup>-1</sup>（x）=-（x<sup>2</sup>+4）<sup>1/2</sup>（定义域为x≥0,值域为y≤-2） （2）∵a<sub>1</sub>=1,a<sub>n</sub>=f<sup>-1</sup>(a<sub>n-1</sub>)由迭代法得:a<sub>n</sub>=-(a<sub>n-1</sub><sup>2</sup>+4)<sup>1/2</sup>=-(a<sub>n-2</sub><sup>2</sup>+2×4)<sup>1/2</sup>=…=-（a<sub>1</sub><sup>2</sup>+（n-1）4）<sup>1/2</sup>=-（4n-3）<sup>1/2</sup>(亦可由a<sub>n</sub><sup>2</sup>=a<sub>n-1</sub><sup>2</sup>+4,n=2,3,…n,累加而得) （3） 注意到 a<sub>n</sub><sup>2</sup>-a<sub>n-1</sub><sup>2</sup>=4,
基金National Key Technology R&D Program"New Drug Innovation"of China(Grant No.2012ZX09301002-002-002,2012ZX09304-005)
文摘Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. Their structures were determined by spectroscopic analysis and identified as quercetin （1）, quercetin 7-O-α-L-rhamnoside （2）, quercetin 3-O-α-L- rhamnoside （3）, 3-O-methyl quercetin （4）, 1,5-dihydroxyxanthone （5）, 1,5-dihydroxyxanthone-6-O-β-D-glucoside （6）, 5-hydroxy- l-methoxyxanthone （7） and 6-deoxyisojacareubin （8）. All these compounds were isolated from this title plant for the first time, and compounds 5-8 were obtained from genus Arenaria for the first time.
文摘A series of material ejections associated with flares are observed in AR 5395 during 8 to 19 March, 1989. five events selected are repoted in this paper.
文摘[Objective] The aim was to understand the species composition, distribution, density, seasonal fluctuation and pathogens of mosquitoes in four regions of East China to provide basic data for prevention and control of mosquitoes at ports. [Method] The mosquitoes at 21 ports of four regions in East China were investigated during 2011-2014 by CO2 lamp method, egg collection method, scoop method and visual method. The species of mosquitoes was identified, and pathogens in mosquitoes were detected. [Result] From 2011 to 2014, 102 583 mosquitoes were captured at the ports, belonging to 18 species, 6 genera and 1 family. Culex pipi- ens quinquefasciatus or Culex pipiens pallens was the dominant species at most ports. Mosquitoes could be captured from May to October, and the captured mosquitoes were the most in June. The positive rate of egg collectors was 9.41%, and the positive rate of breeding places was 7.23%. Rare entry mosquitoes were captured, and most of them were C. pipiens pallens. The detection results of dengue fever, malaria and other pathogens were negative. [Conclusion] C. pipiens quinquefasciatus or C. pipiens pallens was dominant at most ports, and the peak period was June. There were breeding environments of mosquitoes at some ports, so the prevention and control of mosquitoes at these ports should be paid more at- tention to in future.
