The data of the year 1992 from 25 geomagnetic observatories affiliated to the geomagnetic network of State Seismological Bureau of China were processed using the principle of geomagnetic spatial gradient method. Throu...The data of the year 1992 from 25 geomagnetic observatories affiliated to the geomagnetic network of State Seismological Bureau of China were processed using the principle of geomagnetic spatial gradient method. Through finding out the polynomial form of optimum fitting, comparatively good C values for four harmonic components of diurnal variations were obtained. By using the inverse method of non linear underdetermined problem, the electrical conductivity structures under the observatories were investgated. It is shown that there are differences of the C values and conductivity structures in the deep underground under the south western part and northern parts and other parts of China. We studied the possibility of improving the gradient method for investigation of the deep underground conductivity structure, and it is indicated that the gradient method is hopeful in the investigation of earth′s deep conductivity structure and the applied studies concerned.展开更多
目的:建立反相高效液相色谱法测定苯酰甲硝唑有关物质。方法:采用双波长检测,梯度洗脱。色谱柱为迪马公司 Dia-monsil^(TM)C_(18)(250mm×4.6mm,5μm);流动相 A 和 B 分别为1.5g·L^(-1)磷酸二氢钾溶液(用1mol·L^(-1)磷酸...目的:建立反相高效液相色谱法测定苯酰甲硝唑有关物质。方法:采用双波长检测,梯度洗脱。色谱柱为迪马公司 Dia-monsil^(TM)C_(18)(250mm×4.6mm,5μm);流动相 A 和 B 分别为1.5g·L^(-1)磷酸二氢钾溶液(用1mol·L^(-1)磷酸溶液调 pH3.2)-乙腈(80:20和58:42);流速1.0mL·min^(-1),检测波长为235,315nm,进样量20μL,柱温为室温,外标法和主成分自身对照法计算。结果:杂质 A、杂质 B、杂质 C、苯酰甲硝唑均能达到很好的分离,并分别在1.12~16.8μg·mL^(-1)(r=1.000),1.12~16.8μg·mL^(-1)(r=0.9999),1.0~15.0μg·mL^(-1)(r=1.000),1.04~15.6μg·mL^(-1)(r=0.9992)浓度范围内具有良好的线性关系。杂质 A、杂质 B、杂质 C 的平均回收率(n=9)分别为99.4%,99.6%,99.5%。结论:本法简便、灵敏、准确,专属性强,适合于苯酰甲硝唑有关物质的测定。展开更多
文摘The data of the year 1992 from 25 geomagnetic observatories affiliated to the geomagnetic network of State Seismological Bureau of China were processed using the principle of geomagnetic spatial gradient method. Through finding out the polynomial form of optimum fitting, comparatively good C values for four harmonic components of diurnal variations were obtained. By using the inverse method of non linear underdetermined problem, the electrical conductivity structures under the observatories were investgated. It is shown that there are differences of the C values and conductivity structures in the deep underground under the south western part and northern parts and other parts of China. We studied the possibility of improving the gradient method for investigation of the deep underground conductivity structure, and it is indicated that the gradient method is hopeful in the investigation of earth′s deep conductivity structure and the applied studies concerned.
文摘目的:建立反相高效液相色谱法测定苯酰甲硝唑有关物质。方法:采用双波长检测,梯度洗脱。色谱柱为迪马公司 Dia-monsil^(TM)C_(18)(250mm×4.6mm,5μm);流动相 A 和 B 分别为1.5g·L^(-1)磷酸二氢钾溶液(用1mol·L^(-1)磷酸溶液调 pH3.2)-乙腈(80:20和58:42);流速1.0mL·min^(-1),检测波长为235,315nm,进样量20μL,柱温为室温,外标法和主成分自身对照法计算。结果:杂质 A、杂质 B、杂质 C、苯酰甲硝唑均能达到很好的分离,并分别在1.12~16.8μg·mL^(-1)(r=1.000),1.12~16.8μg·mL^(-1)(r=0.9999),1.0~15.0μg·mL^(-1)(r=1.000),1.04~15.6μg·mL^(-1)(r=0.9992)浓度范围内具有良好的线性关系。杂质 A、杂质 B、杂质 C 的平均回收率(n=9)分别为99.4%,99.6%,99.5%。结论:本法简便、灵敏、准确,专属性强,适合于苯酰甲硝唑有关物质的测定。