he present paper covers a model involving Donnan memhrane equilibrium andadsorption eluilibrium to describe the retention process for diprotic organic acids inion-exclusion chromatography. On this basis the microcompu...he present paper covers a model involving Donnan memhrane equilibrium andadsorption eluilibrium to describe the retention process for diprotic organic acids inion-exclusion chromatography. On this basis the microcomputer simulation of elu-tion behaviour for dicarboxylic acids was investigated. Influences of eluent acidityand sample concentration on the retention value were studied. The theoreticallypredicted results are in reasonable agreement with the experimental data.展开更多
The elution of lead from vermiculite was investigated by using a novel biodegradable chelating reagent, L asparagic N,N diacetic acid (ASDA) and water soluble depolymerized pectic acid and comparing with a conventiona...The elution of lead from vermiculite was investigated by using a novel biodegradable chelating reagent, L asparagic N,N diacetic acid (ASDA) and water soluble depolymerized pectic acid and comparing with a conventional chelating reagent, EDTA, as well as acetic acid. The influences of the reagent concentration, equilibrium pH and the suspension contact time on Pb extraction were examined. It is concluded that the acetic acid is not effective for Pb removal in any case due to its weak complexing ability with Pb. Although Pb is easier to be released by EDTA with stoichiometric amount, it is by no means the preferable alternative for the purpose because of its low biodegradability. On the other hand, ASDA and depolymerized pectic acid have the potential application because they are not only effective for Pb elution but also environmentally friendly.展开更多
目的:建立HPLC-DAD法测定“武当三号金银花”藤中4种有效成分的含量。方法采用Fortis Xi Phenyl柱(250 mm×4.6 mm,5μm);流动相为乙腈(A)-0.5%冰醋酸溶液(B)进行线性梯度洗脱;马钱苷、绿原酸、芦丁、木犀草苷检测波长分别...目的:建立HPLC-DAD法测定“武当三号金银花”藤中4种有效成分的含量。方法采用Fortis Xi Phenyl柱(250 mm×4.6 mm,5μm);流动相为乙腈(A)-0.5%冰醋酸溶液(B)进行线性梯度洗脱;马钱苷、绿原酸、芦丁、木犀草苷检测波长分别为236、327、354、348 nm;柱温:30℃。结果马钱苷、绿原酸、芦丁、木犀草苷4个化合物在各自测定的范围内均呈良好的线性关系(r≥0.9994),平均回收率为98.9%-99.9%。结论该法操作简单,灵敏度高,重现性好,为较全面控制“武当三号金银花”藤的质量提供了一种可靠的方法。展开更多
文摘he present paper covers a model involving Donnan memhrane equilibrium andadsorption eluilibrium to describe the retention process for diprotic organic acids inion-exclusion chromatography. On this basis the microcomputer simulation of elu-tion behaviour for dicarboxylic acids was investigated. Influences of eluent acidityand sample concentration on the retention value were studied. The theoreticallypredicted results are in reasonable agreement with the experimental data.
文摘The elution of lead from vermiculite was investigated by using a novel biodegradable chelating reagent, L asparagic N,N diacetic acid (ASDA) and water soluble depolymerized pectic acid and comparing with a conventional chelating reagent, EDTA, as well as acetic acid. The influences of the reagent concentration, equilibrium pH and the suspension contact time on Pb extraction were examined. It is concluded that the acetic acid is not effective for Pb removal in any case due to its weak complexing ability with Pb. Although Pb is easier to be released by EDTA with stoichiometric amount, it is by no means the preferable alternative for the purpose because of its low biodegradability. On the other hand, ASDA and depolymerized pectic acid have the potential application because they are not only effective for Pb elution but also environmentally friendly.