Silica gel bonded stationary phases containing monoaza crown ether was synthesized via a series of solid-liquid phase reactions. The bonded molecular structure was characterized by chemical and instrumental analyses. ...Silica gel bonded stationary phases containing monoaza crown ether was synthesized via a series of solid-liquid phase reactions. The bonded molecular structure was characterized by chemical and instrumental analyses. The bonded stationary phase was provided with complexing ability with copper ion as well as hydrophobic property. The chromatographic retention behaviours of some substituted polar phenol derivatives, organic acids and bases on the bonded stationary phase were studied using methanol and/or aqueous solution of dibasic potassium phosphate buffer as mobile phase. When copper ion was added to the mobile phase at pH 5.4, the retention of substituted phenols became strong.展开更多
The metabolism of 7-(4-Chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB), a potential anti-arrhythmia and anti-ischemia drug,was studied in rat bile. A metabolite and unchanged CTHB were found in the bile. C...The metabolism of 7-(4-Chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB), a potential anti-arrhythmia and anti-ischemia drug,was studied in rat bile. A metabolite and unchanged CTHB were found in the bile. Characterization and structural elucidation of the metabolite was achieved by LC/MS and LC/NMR.展开更多
This is a continuation of short communication([1]). In [1] a verification of the implicitization equation for degree two rational Bezier curves is presented which does not require the use of resultants. This paper pre...This is a continuation of short communication([1]). In [1] a verification of the implicitization equation for degree two rational Bezier curves is presented which does not require the use of resultants. This paper presents these verifications in the general cases, i.e., for degree n rational Bezier curves. Thus some interesting interplay between the structure of the n x n implicitization matrix and the de Casteljau algorithm is revealed.展开更多
文摘Silica gel bonded stationary phases containing monoaza crown ether was synthesized via a series of solid-liquid phase reactions. The bonded molecular structure was characterized by chemical and instrumental analyses. The bonded stationary phase was provided with complexing ability with copper ion as well as hydrophobic property. The chromatographic retention behaviours of some substituted polar phenol derivatives, organic acids and bases on the bonded stationary phase were studied using methanol and/or aqueous solution of dibasic potassium phosphate buffer as mobile phase. When copper ion was added to the mobile phase at pH 5.4, the retention of substituted phenols became strong.
文摘The metabolism of 7-(4-Chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB), a potential anti-arrhythmia and anti-ischemia drug,was studied in rat bile. A metabolite and unchanged CTHB were found in the bile. Characterization and structural elucidation of the metabolite was achieved by LC/MS and LC/NMR.
文摘This is a continuation of short communication([1]). In [1] a verification of the implicitization equation for degree two rational Bezier curves is presented which does not require the use of resultants. This paper presents these verifications in the general cases, i.e., for degree n rational Bezier curves. Thus some interesting interplay between the structure of the n x n implicitization matrix and the de Casteljau algorithm is revealed.
