研究了影响浊度法定量测定3种类型驱油聚合物的因素。所用实验聚合物样品有抗盐型6种,疏水缔合型一种,常规HPAM型2种。在测定浓度100-800 mg/L的一种抗盐型聚合物样品时,冰醋酸、次氯酸钠与聚合物的反应时间在13-17 m in范围时,浊度测...研究了影响浊度法定量测定3种类型驱油聚合物的因素。所用实验聚合物样品有抗盐型6种,疏水缔合型一种,常规HPAM型2种。在测定浓度100-800 mg/L的一种抗盐型聚合物样品时,冰醋酸、次氯酸钠与聚合物的反应时间在13-17 m in范围时,浊度测定值（NTU值）相对稳定,但在反应时间为3-20 m in时,每一反应时间的聚合物浓度-浊度曲线均具有良好的线性关系,拟合线性方程R2〉0.999,浓度测定值相对误差〈5%。对于4种抗盐型聚合物样品和一种剪切不同时间（0-120 m in）的HPAM样品,在水解度相近、浓度相同条件下,均观察到聚合物相对分子质量增大时浊度测定值差别增大的现象。一种抗盐型聚合物样品,在相同浓度下,水解度较低者浊度测定值较高。结论是浊度法可用于矿场注入的这三类聚合物溶液浓度的测定,可测浓度范围100-900 mg/L,反应时间3 m in即可。报道了一种HPAM型,一种疏水缔合型及一种抗盐型聚合物的浓度-浊度标准工作曲线,其拟合线性方程的R2值分别为0.9995、0.9989和0.9995,浓度测定值相对误差分别为1.24%、2.23%和1.82%。展开更多
To determine the diet security of brown algal polyphenols, we studied the acute toxicity and 90 day’s feed toxicity on brown algal polyphenols isolated from Sargassum kjellmanianum. The lethal dose 50 for rat is 1 23...To determine the diet security of brown algal polyphenols, we studied the acute toxicity and 90 day’s feed toxicity on brown algal polyphenols isolated from Sargassum kjellmanianum. The lethal dose 50 for rat is 1 230×10-6,with 95% confidence ranged from 791.4×10-6 to 1 912.4×10-6. The 90 day′s feeding experiment showed that the mouses administered brown algal polyphenols maintain regular conditions, with no difference to the control group on blood biochemical index, weight, and pathology analysis. The results indicated that brown algal polyphenols is safe as food additive.展开更多
The interrelations between thylakoid polypeptide components and Mg 2+ induced Chl a fluorescence and thylakoid surface charge changes were investigated in Zostera marina chloroplasts treated with Ca 2+ and...The interrelations between thylakoid polypeptide components and Mg 2+ induced Chl a fluorescence and thylakoid surface charge changes were investigated in Zostera marina chloroplasts treated with Ca 2+ and trypsin. It was observed that:1. The increase of Mg 2+ induced PSⅡ fluorescence intensity was closely related to the decrease of Mg 2+ induced surface charge density of the thylakoid membrane in the normal chloroplast; 2. Removal of the 32~34 kD polypeptides of the thylakoid surface by Ca 2+ extraction of the chloroplast did not affect the Mg 2+ induced phenomena; 3. If the Ca 2+ treated chloroplast was further digested by trypsin to remove the 26 kD polypeptide of the membrane surface, the Mg 2+ induced phenomena disappeared completely. These results clearly indicated that the 26 kD polypeptide of thylakoid surface is the specific acting site of the cation that induced these two correlated phenomena in the chloroplast from Zostera marina. The mechanism on the regulating effect of the cation on excitation energy distribution between PSⅡ and PSⅠ was discussed.展开更多
文摘研究了影响浊度法定量测定3种类型驱油聚合物的因素。所用实验聚合物样品有抗盐型6种,疏水缔合型一种,常规HPAM型2种。在测定浓度100-800 mg/L的一种抗盐型聚合物样品时,冰醋酸、次氯酸钠与聚合物的反应时间在13-17 m in范围时,浊度测定值（NTU值）相对稳定,但在反应时间为3-20 m in时,每一反应时间的聚合物浓度-浊度曲线均具有良好的线性关系,拟合线性方程R2〉0.999,浓度测定值相对误差〈5%。对于4种抗盐型聚合物样品和一种剪切不同时间（0-120 m in）的HPAM样品,在水解度相近、浓度相同条件下,均观察到聚合物相对分子质量增大时浊度测定值差别增大的现象。一种抗盐型聚合物样品,在相同浓度下,水解度较低者浊度测定值较高。结论是浊度法可用于矿场注入的这三类聚合物溶液浓度的测定,可测浓度范围100-900 mg/L,反应时间3 m in即可。报道了一种HPAM型,一种疏水缔合型及一种抗盐型聚合物的浓度-浊度标准工作曲线,其拟合线性方程的R2值分别为0.9995、0.9989和0.9995,浓度测定值相对误差分别为1.24%、2.23%和1.82%。
文摘To determine the diet security of brown algal polyphenols, we studied the acute toxicity and 90 day’s feed toxicity on brown algal polyphenols isolated from Sargassum kjellmanianum. The lethal dose 50 for rat is 1 230×10-6,with 95% confidence ranged from 791.4×10-6 to 1 912.4×10-6. The 90 day′s feeding experiment showed that the mouses administered brown algal polyphenols maintain regular conditions, with no difference to the control group on blood biochemical index, weight, and pathology analysis. The results indicated that brown algal polyphenols is safe as food additive.
基金the NationalNaturalScience Foundation ofChina and partly supported
文摘The interrelations between thylakoid polypeptide components and Mg 2+ induced Chl a fluorescence and thylakoid surface charge changes were investigated in Zostera marina chloroplasts treated with Ca 2+ and trypsin. It was observed that:1. The increase of Mg 2+ induced PSⅡ fluorescence intensity was closely related to the decrease of Mg 2+ induced surface charge density of the thylakoid membrane in the normal chloroplast; 2. Removal of the 32~34 kD polypeptides of the thylakoid surface by Ca 2+ extraction of the chloroplast did not affect the Mg 2+ induced phenomena; 3. If the Ca 2+ treated chloroplast was further digested by trypsin to remove the 26 kD polypeptide of the membrane surface, the Mg 2+ induced phenomena disappeared completely. These results clearly indicated that the 26 kD polypeptide of thylakoid surface is the specific acting site of the cation that induced these two correlated phenomena in the chloroplast from Zostera marina. The mechanism on the regulating effect of the cation on excitation energy distribution between PSⅡ and PSⅠ was discussed.
