A new method for determination of Cu(Ⅱ) by DDCT chelating resin preconcentration and thin layer resin phase spectrophotometry was developed. The method has a high sensitivity (ε455= 3.6×10^5L/mol·cm), ...A new method for determination of Cu(Ⅱ) by DDCT chelating resin preconcentration and thin layer resin phase spectrophotometry was developed. The method has a high sensitivity (ε455= 3.6×10^5L/mol·cm), which is 33 times higher than that of liquid phase spectrophotometry. It has a good selectivity (most coexisting ions could not influence determination) and an ideal precision [30μg Cu(Ⅱ), n=6, RSD= l.67%]. The content of Cu(Ⅱ) in water, high purity rare earth and its oxide was determined. The detection limit of Cu(Ⅱ) is 5.3μg/L , and the linear range is 0-7.2μg/ml. The result is satisfactory.展开更多
The article design the hardware system scheme using STM32F407 as the control core circuit, and designed the software structure of the system and application layer multi task and priority based on transplanted μ C/OS ...The article design the hardware system scheme using STM32F407 as the control core circuit, and designed the software structure of the system and application layer multi task and priority based on transplanted μ C/OS operating system. Aimed at that the traditional drunk driving detection system has low sensitivity and unable to distinguish diffuse alcohol sigmal interference. For accurate identification of pilot and crew alcohol concentration, the paper puts forward a driving intelligent identification wine system based on embedded μC/OS- II. The experimental results show that the detection sensitivity of the system has high accuracy rate, effectively prevent the purpose for the prevention of drunk driving, drunk driving has very good practical value.展开更多
An all optical fiber gas sensor is presented to detect the concentration of NH3 and CO. Based on the spectral absorption, The wideband light source is used to reflect two narrowband spectra by fiber grating of differe...An all optical fiber gas sensor is presented to detect the concentration of NH3 and CO. Based on the spectral absorption, The wideband light source is used to reflect two narrowband spectra by fiber grating of different duty. and piezoelectric ceramics to obtain narrowband output light. The high sensitivity detection can be measured from the second harmonic signal. The two narrowband spectra are corresponding to the absorption spectra of NH3 and CO. Concentration detection are realized by the detection of variety of light intensity. Sensitivity is proved and cost is reduced.展开更多
In this study, Al/TiO2/Al2O3/p-Si was fabricated as a gas sensor. TiO2 and Al2O3 were grown by Atomic Layer Deposition method. The prepared film was tested in various gas concentrations at different operating temperat...In this study, Al/TiO2/Al2O3/p-Si was fabricated as a gas sensor. TiO2 and Al2O3 were grown by Atomic Layer Deposition method. The prepared film was tested in various gas concentrations at different operating temperatures ranging between 27 ℃ to 177 ℃. The sensitivity increases with increasing gas concentration and operating temperature which have a direct effect on sensing surface. The gas sensing mechanism could be explained with the surface controlled type based on the change of the electrical conductance of the semiconducting material. This mechanism is controlled by CO molecules and the amount of chemisorbed oxygen on the surface which is associated with temperature. Sample exhibits the basic parameters for gas sensors applications which are good stability, reproducibility and high sensitivity to CO gas which are. In addition, the response and recovery times are measured 19 and 26 s, respectively.展开更多
文摘A new method for determination of Cu(Ⅱ) by DDCT chelating resin preconcentration and thin layer resin phase spectrophotometry was developed. The method has a high sensitivity (ε455= 3.6×10^5L/mol·cm), which is 33 times higher than that of liquid phase spectrophotometry. It has a good selectivity (most coexisting ions could not influence determination) and an ideal precision [30μg Cu(Ⅱ), n=6, RSD= l.67%]. The content of Cu(Ⅱ) in water, high purity rare earth and its oxide was determined. The detection limit of Cu(Ⅱ) is 5.3μg/L , and the linear range is 0-7.2μg/ml. The result is satisfactory.
文摘The article design the hardware system scheme using STM32F407 as the control core circuit, and designed the software structure of the system and application layer multi task and priority based on transplanted μ C/OS operating system. Aimed at that the traditional drunk driving detection system has low sensitivity and unable to distinguish diffuse alcohol sigmal interference. For accurate identification of pilot and crew alcohol concentration, the paper puts forward a driving intelligent identification wine system based on embedded μC/OS- II. The experimental results show that the detection sensitivity of the system has high accuracy rate, effectively prevent the purpose for the prevention of drunk driving, drunk driving has very good practical value.
文摘An all optical fiber gas sensor is presented to detect the concentration of NH3 and CO. Based on the spectral absorption, The wideband light source is used to reflect two narrowband spectra by fiber grating of different duty. and piezoelectric ceramics to obtain narrowband output light. The high sensitivity detection can be measured from the second harmonic signal. The two narrowband spectra are corresponding to the absorption spectra of NH3 and CO. Concentration detection are realized by the detection of variety of light intensity. Sensitivity is proved and cost is reduced.
文摘In this study, Al/TiO2/Al2O3/p-Si was fabricated as a gas sensor. TiO2 and Al2O3 were grown by Atomic Layer Deposition method. The prepared film was tested in various gas concentrations at different operating temperatures ranging between 27 ℃ to 177 ℃. The sensitivity increases with increasing gas concentration and operating temperature which have a direct effect on sensing surface. The gas sensing mechanism could be explained with the surface controlled type based on the change of the electrical conductance of the semiconducting material. This mechanism is controlled by CO molecules and the amount of chemisorbed oxygen on the surface which is associated with temperature. Sample exhibits the basic parameters for gas sensors applications which are good stability, reproducibility and high sensitivity to CO gas which are. In addition, the response and recovery times are measured 19 and 26 s, respectively.