A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensiti...A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensitivity and stability. It responds to the activity of sulfide ions according to a Nernstian slope of -31mV/decade. The sensor can be used to determine the total concentration of sulfides ( C T) by calibrating the pH value of the solution to a standard pH. The practical measurement range for total sulfide concentration is 0.1-10 mg/L in seawater. The sensor has a very low potential drift (<4mV) during two months in 0.1 mg/L sulfide seawater. This paper describes the preparation of the sensitive membrane and some main properties of the sensor.展开更多
A novel method for developing a reliable data driven soft sensor to improve the prediction accuracy of sulfur content in hydrodesulfurization(HDS) process was proposed. Therefore, an integrated approach using support ...A novel method for developing a reliable data driven soft sensor to improve the prediction accuracy of sulfur content in hydrodesulfurization(HDS) process was proposed. Therefore, an integrated approach using support vector regression(SVR) based on wavelet transform(WT) and principal component analysis(PCA) was used. Experimental data from the HDS setup were employed to validate the proposed model. The results reveal that the integrated WT-PCA with SVR model was able to increase the prediction accuracy of SVR model. Implementation of the proposed model delivers the best satisfactory predicting performance(EAARE=0.058 and R2=0.97) in comparison with SVR. The obtained results indicate that the proposed model is more reliable and more precise than the multiple linear regression(MLR), SVR and PCA-SVR.展开更多
Conventional Pd/γ-A12O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent decrease in sensitivity and the working life of methane sensors. We mainly investigated the effect of n...Conventional Pd/γ-A12O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent decrease in sensitivity and the working life of methane sensors. We mainly investigated the effect of nanotechnology and a cerium co-catalyst on the stability and anti-sulfur performance of methane sensors. In our experiment, an anti-sulfur methane sensor was prepared by immersing cerium-containing γ-alumina nanometer elements into a Pt-Pd bimetallic nanometer catalyst. The experi- ment about the sensitivity and stability performance of different catalytic methane sensors indicate that sensitivity, decreased by catalyst sulfur poisoning, is improved significantly by adding cerium to the vector. As well, the long-term operational stability of methane sensors increased significantly.展开更多
By applying an indirect strategy, a new copper （II） complex of a thiosemicarbazone L has been successfully developed as a colorimetric cbemosensor for the sensitive detection of mercury （II） ions. In the presence ...By applying an indirect strategy, a new copper （II） complex of a thiosemicarbazone L has been successfully developed as a colorimetric cbemosensor for the sensitive detection of mercury （II） ions. In the presence of copper （II） ions, the colorless so- lution of L became yellow; however, upon the addition of traces of mercury （II） ions, the yellow color faded to colorless im- mediately. Other ions, including Fe3＋, Ag＋, Ca2＋, Zn2＋, Pb2＋, Cd2＋, Ni2＋, Co2＋, Cr3＋ and Mg2＋ had a negligible influence on the probe behavior. The detection limits were 5.0×10^-6 M and 3.0×10^-7 M of Hg2＋ using the visual color changes and UV-vis changes respectively. Test strips based on Cu-L were fabricated, which could act as a convenient and efficient Hg2＋ test kits.展开更多
The different interactions between a chemosensor, 1-（naphthalen-2-yl）-3-（6-nitrobenzothiazol-2-yl）-thiourea （1）, and F, acetate （AcO-）, Cl-, and Br- anions have been investigated theoretically at the B3LYP/6-3...The different interactions between a chemosensor, 1-（naphthalen-2-yl）-3-（6-nitrobenzothiazol-2-yl）-thiourea （1）, and F, acetate （AcO-）, Cl-, and Br- anions have been investigated theoretically at the B3LYP/6-31＋G（d,p） level with the basis set superposition error （BSSE） correction. It was found that the high selectivity of compound 1 for F- can be ascribed to the ability of the anion to deprotonate the N-H fragment of the host sensor, while the chemosensor also has a strong affinity for AcO- by virtue of the formation of a hydrogen-bonded complex. Intramolecular charge transfer （ICT） causes the colorimetric signaling of compound 1 after interaction with F-/AcO. A study of substituent effects suggested that the O/NH- and O/S-substituted derivatives are also expected to be promising candidates for chromogenic F3AcO chemosensors.展开更多
文摘A new convenient sulfide electrochemical sensor for marine environmental in situ monitoring and real time survey was developed. The new sensor based on a solid Ag 2S membrane electrode has outstanding chemical sensitivity and stability. It responds to the activity of sulfide ions according to a Nernstian slope of -31mV/decade. The sensor can be used to determine the total concentration of sulfides ( C T) by calibrating the pH value of the solution to a standard pH. The practical measurement range for total sulfide concentration is 0.1-10 mg/L in seawater. The sensor has a very low potential drift (<4mV) during two months in 0.1 mg/L sulfide seawater. This paper describes the preparation of the sensitive membrane and some main properties of the sensor.
文摘A novel method for developing a reliable data driven soft sensor to improve the prediction accuracy of sulfur content in hydrodesulfurization(HDS) process was proposed. Therefore, an integrated approach using support vector regression(SVR) based on wavelet transform(WT) and principal component analysis(PCA) was used. Experimental data from the HDS setup were employed to validate the proposed model. The results reveal that the integrated WT-PCA with SVR model was able to increase the prediction accuracy of SVR model. Implementation of the proposed model delivers the best satisfactory predicting performance(EAARE=0.058 and R2=0.97) in comparison with SVR. The obtained results indicate that the proposed model is more reliable and more precise than the multiple linear regression(MLR), SVR and PCA-SVR.
基金support for this work, provided by the National Natural Science Foundation of China (No60910005)
文摘Conventional Pd/γ-A12O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent decrease in sensitivity and the working life of methane sensors. We mainly investigated the effect of nanotechnology and a cerium co-catalyst on the stability and anti-sulfur performance of methane sensors. In our experiment, an anti-sulfur methane sensor was prepared by immersing cerium-containing γ-alumina nanometer elements into a Pt-Pd bimetallic nanometer catalyst. The experi- ment about the sensitivity and stability performance of different catalytic methane sensors indicate that sensitivity, decreased by catalyst sulfur poisoning, is improved significantly by adding cerium to the vector. As well, the long-term operational stability of methane sensors increased significantly.
基金supported by the National Natural Science Foundation of China (21262032, 21064006 and 21161018)the Natural Science Foundation of Gansu Province (1010RJZA018)the Program for Changjian Scholars and Innovative Research Team in University of Minisry of Education of China (IRT1177)
文摘By applying an indirect strategy, a new copper （II） complex of a thiosemicarbazone L has been successfully developed as a colorimetric cbemosensor for the sensitive detection of mercury （II） ions. In the presence of copper （II） ions, the colorless so- lution of L became yellow; however, upon the addition of traces of mercury （II） ions, the yellow color faded to colorless im- mediately. Other ions, including Fe3＋, Ag＋, Ca2＋, Zn2＋, Pb2＋, Cd2＋, Ni2＋, Co2＋, Cr3＋ and Mg2＋ had a negligible influence on the probe behavior. The detection limits were 5.0×10^-6 M and 3.0×10^-7 M of Hg2＋ using the visual color changes and UV-vis changes respectively. Test strips based on Cu-L were fabricated, which could act as a convenient and efficient Hg2＋ test kits.
基金supported by the Natural Science Foundation of Inner Mongolia Autonomous Region (2011ZD02)
文摘The different interactions between a chemosensor, 1-（naphthalen-2-yl）-3-（6-nitrobenzothiazol-2-yl）-thiourea （1）, and F, acetate （AcO-）, Cl-, and Br- anions have been investigated theoretically at the B3LYP/6-31＋G（d,p） level with the basis set superposition error （BSSE） correction. It was found that the high selectivity of compound 1 for F- can be ascribed to the ability of the anion to deprotonate the N-H fragment of the host sensor, while the chemosensor also has a strong affinity for AcO- by virtue of the formation of a hydrogen-bonded complex. Intramolecular charge transfer （ICT） causes the colorimetric signaling of compound 1 after interaction with F-/AcO. A study of substituent effects suggested that the O/NH- and O/S-substituted derivatives are also expected to be promising candidates for chromogenic F3AcO chemosensors.
