A novel chemiluminescence(CL) biosensor for the determination of oxalate is presented in this paper. It is based on the CL reaction between luminol, immobilized on an anion-exchange column, and hydrogen peroxide gener...A novel chemiluminescence(CL) biosensor for the determination of oxalate is presented in this paper. It is based on the CL reaction between luminol, immobilized on an anion-exchange column, and hydrogen peroxide generated on-linevia oxalate by the catalytic effect of oxalate oxidase in spinach in the flow cell. The biosensor responds linearly to oxalate concentration in the range of 4 0×10^-7 to 1 0×10^-4 mol/L, and the detection limit is 2×10^-7 mol/L. A complete analysis could be performed in 1 min with a relative standard deviation of 3 7% for 1 0×10^-5 mol/L oxalate(n=7). The system is stable for over 200 times determinations and has been applied in urine samples.展开更多
The complex permittivity of targeted objects is an important factor that influences its microwave radiation and scattering characteristics.In the quantitative research of microwave remote sensing,the study of the diel...The complex permittivity of targeted objects is an important factor that influences its microwave radiation and scattering characteristics.In the quantitative research of microwave remote sensing,the study of the dielectric properties of the vegetation to establish the relationship between its specific physical parameters and complex permittivity is fundamental.In this study,six categories of vegetation samples were collected at the city of Zhangye,a key research area of the Heihe watershed allied telemetry experimental research.The vector network analyzer E8362B was used to measure the complex permittivity of these samples from 0.2 to 20 GHz by the coaxial probe technique.The research focused mainly on the corn leaves,and an empirical model was established between the gravimetric moisture and the real/imaginary parts of complex permittivity at the main frequency points of microwave sensors.Furthermore,the empirical model and the classical Debye-Cole model were compared and verified by the measured data collected from the Huailai County of Hebei Province.The results show that the newly- established empirical model is more accurate and more practical as compared to the traditional Debye-Cole model.展开更多
文摘A novel chemiluminescence(CL) biosensor for the determination of oxalate is presented in this paper. It is based on the CL reaction between luminol, immobilized on an anion-exchange column, and hydrogen peroxide generated on-linevia oxalate by the catalytic effect of oxalate oxidase in spinach in the flow cell. The biosensor responds linearly to oxalate concentration in the range of 4 0×10^-7 to 1 0×10^-4 mol/L, and the detection limit is 2×10^-7 mol/L. A complete analysis could be performed in 1 min with a relative standard deviation of 3 7% for 1 0×10^-5 mol/L oxalate(n=7). The system is stable for over 200 times determinations and has been applied in urine samples.
基金supported by the Chinese Ministry of Science and Technology(Grant Nos.2011AA120403&2010CB951403)the National Natural Science Foundation of China(Grant No.41101391)
文摘The complex permittivity of targeted objects is an important factor that influences its microwave radiation and scattering characteristics.In the quantitative research of microwave remote sensing,the study of the dielectric properties of the vegetation to establish the relationship between its specific physical parameters and complex permittivity is fundamental.In this study,six categories of vegetation samples were collected at the city of Zhangye,a key research area of the Heihe watershed allied telemetry experimental research.The vector network analyzer E8362B was used to measure the complex permittivity of these samples from 0.2 to 20 GHz by the coaxial probe technique.The research focused mainly on the corn leaves,and an empirical model was established between the gravimetric moisture and the real/imaginary parts of complex permittivity at the main frequency points of microwave sensors.Furthermore,the empirical model and the classical Debye-Cole model were compared and verified by the measured data collected from the Huailai County of Hebei Province.The results show that the newly- established empirical model is more accurate and more practical as compared to the traditional Debye-Cole model.
