dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultan...dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultaneous determination of uranium and thorium without prior separation. Various molar ratios of uranium/thorium, from 0.5∶1 to 10∶1, can be determined with satisfactory precision and accuracy. Uranium and thorium content in a phosphate ore and simulated sample were determined, the recoveries were 98.4%～102.5% for uranium and 96.8%～102.3% for thorium, the relative standard deviations (R.S.D) were 1.5%～2.3% for uranium and 2.1%～3.1% for thorium.展开更多
A method for fast determination of the component in complex samples by using gas chromatography-mass spectrometry （GC-MS） was developed and used for quantitative analysis of phenanthrene in soils. In the method, win...A method for fast determination of the component in complex samples by using gas chromatography-mass spectrometry （GC-MS） was developed and used for quantitative analysis of phenanthrene in soils. In the method, window independent component analysis （WICA） was used for resolving the mass spectrum and non-negative im- mune algorithm （NNIA） was employed for obtaining the chromatographic profile. Therefore, spectral and chroma- tographic information of a specific component can be obtained from the measured GC-MS data of overlapping and high background. Six soil samples collected from different places were analyzed. The tedious pretreatments in pre- paring the samples and the elution in the separation were simplified for speeding up the analysis. Due to the com- plexity of the matrix, standard addition method was adopted for the final quantification. The applicability of the method was validated with a spiked sample and the results of the six samples are reasonable.展开更多
It is almost impossible to determine the thermochemical data of all the compounds by experiments. Many methods for estimating the thermochemical data of organics have been proposed in the past 50 years. Benson’s grou...It is almost impossible to determine the thermochemical data of all the compounds by experiments. Many methods for estimating the thermochemical data of organics have been proposed in the past 50 years. Benson’s group additivity method which has the advantage of quickness, ease and accuracy is regarded as the most successful one among these empirical methods. Unfortunately, the group values used in Benson’s method are not sufficient, since they come from the experimental thermochemical data and the number of the groups in Benson’s group additivity method depends on the number of the orginc compounds that can be estimated. In this note, the molecular mechanics method is used展开更多
文摘dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultaneous determination of uranium and thorium without prior separation. Various molar ratios of uranium/thorium, from 0.5∶1 to 10∶1, can be determined with satisfactory precision and accuracy. Uranium and thorium content in a phosphate ore and simulated sample were determined, the recoveries were 98.4%～102.5% for uranium and 96.8%～102.3% for thorium, the relative standard deviations (R.S.D) were 1.5%～2.3% for uranium and 2.1%～3.1% for thorium.
文摘A method for fast determination of the component in complex samples by using gas chromatography-mass spectrometry （GC-MS） was developed and used for quantitative analysis of phenanthrene in soils. In the method, window independent component analysis （WICA） was used for resolving the mass spectrum and non-negative im- mune algorithm （NNIA） was employed for obtaining the chromatographic profile. Therefore, spectral and chroma- tographic information of a specific component can be obtained from the measured GC-MS data of overlapping and high background. Six soil samples collected from different places were analyzed. The tedious pretreatments in pre- paring the samples and the elution in the separation were simplified for speeding up the analysis. Due to the com- plexity of the matrix, standard addition method was adopted for the final quantification. The applicability of the method was validated with a spiked sample and the results of the six samples are reasonable.
基金Project supported by the National Natural Science Foundation of China.
文摘It is almost impossible to determine the thermochemical data of all the compounds by experiments. Many methods for estimating the thermochemical data of organics have been proposed in the past 50 years. Benson’s group additivity method which has the advantage of quickness, ease and accuracy is regarded as the most successful one among these empirical methods. Unfortunately, the group values used in Benson’s method are not sufficient, since they come from the experimental thermochemical data and the number of the groups in Benson’s group additivity method depends on the number of the orginc compounds that can be estimated. In this note, the molecular mechanics method is used
