Ion mobility spectra for ten alcohols have been studied in an ion mobility spectrometry apparatus equipped with a corona discharge ionization source. Using protonated water cluster ions as the reactant ions and clean ...Ion mobility spectra for ten alcohols have been studied in an ion mobility spectrometry apparatus equipped with a corona discharge ionization source. Using protonated water cluster ions as the reactant ions and clean air as the drift gas, the alcohols exhibit different product ion characteristic peaks in their ion mobility spectra. The detection limit for these alcohols is at low concentration pmol/L level according to the concentration calibration by exponential dilution method. Based on the measured ion mobilities, several chemical physics parameters of the ion-molecular interaction at atmosphere were obtained, including the ionic collision cross sections, diffusion coefficients, collision rate constants, and the ionic radii under the hard-sphere model approximation.展开更多
Plasma processes are among the emerging technologies for volatile organic compounds (VOCs) abatement[1]. Both thermal plasmas and non-equilibrium plasmas (cold plasmas) are being developed for VOCs cleanup[2,3]. Parti...Plasma processes are among the emerging technologies for volatile organic compounds (VOCs) abatement[1]. Both thermal plasmas and non-equilibrium plasmas (cold plasmas) are being developed for VOCs cleanup[2,3]. Particularly, pulsed corona discharges offer several advantages over conventional VOCs abatement techniques[4-7]. To optimize the existing technology and to develop it further, there is need to understand the mechanisms involved in plasma chemical reactions. Furthermore, it is strongly desirable to be able to predict the behavior of new VOCs in non-equilibrium plasma environment from the data known for a few representative compounds. Pulsed corona discharge technique is introduced here with citation of relevant literature. Fundamental principles, useful for predicting the VOCs' decomposition behavior, have been worked out from the published literature. Latest developments in the area, targeted to minimize the energy losses, improve the VOCs destruction efficiency and reduce the generation of unwanted organic and inorganic by-products, are presented.展开更多
The welding fume has significant effects on the weld workers＇ health. In order to overwhelm the shortcomings of the control measures of the welding fume, the research of the purifying of welding fume on the spot was ...The welding fume has significant effects on the weld workers＇ health. In order to overwhelm the shortcomings of the control measures of the welding fume, the research of the purifying of welding fume on the spot was carried out. The purifying device was designed. The relationship between the corona discharge voltage and the purifying efficiency was investigated through experiments with different needle electrode numbers, different ring electrode numbers and different needle-plate distances. The results show that 5-needle double-ring electrode has the best efficiency; the purifying efficiency is increase with the lessening of the needle-plate distance and the increase of the discharge voltage. Using 5-needle double-ring electrode, the purifying efficiency reaches its maximum value 97.9% while the needle-plate distance is 6 cm, the discharge voltage is -35 kV. The purifying device has an excellent purifying effect on the welding fume.展开更多
The naphthalene decomposition in a corona radical shower discharge (CRS) was investigated, with attention paid to the influences of voltage and initial naphthalene density. The OH emission spectra were investigated so...The naphthalene decomposition in a corona radical shower discharge (CRS) was investigated, with attention paid to the influences of voltage and initial naphthalene density. The OH emission spectra were investigated so as to know the naphthalene decomposing process. The by-products were analyzed and a decomposing theory in discharge was proposed. The results showed that higher voltage and relative humidity were effective on decomposition. The initial concentration affected the decomposing efficiency of naphthalene. When the initial naphthalene density was 17 mg/m3, the decomposition rate was found to be 70% under 14 kV. The main by-products were carbon dioxide and water. However, a small amount of carbonic oxide, 1,2-ethanediol and acetaldehyde were found due to the incomplete oxidization.展开更多
基金V. ACKNOWLEDGMENTS This work was support by the National Natural Science Foundation of China （No.20577049, No.20707025, and No.20907054）, the Chinese-Slovak Scientific and Technological Cooperation Project （No.4-03）, the Excellent Youth Foundation of Anhui Province Scientific Committee （No.06045098）, the Hefei Institutes of Physical Science, Chinese Academy of Science are gratefully acknowledged, and the Slovak Research and Development Agency, projects （No.LPP-0143-06 and No.SK- CN-029-07）.
文摘Ion mobility spectra for ten alcohols have been studied in an ion mobility spectrometry apparatus equipped with a corona discharge ionization source. Using protonated water cluster ions as the reactant ions and clean air as the drift gas, the alcohols exhibit different product ion characteristic peaks in their ion mobility spectra. The detection limit for these alcohols is at low concentration pmol/L level according to the concentration calibration by exponential dilution method. Based on the measured ion mobilities, several chemical physics parameters of the ion-molecular interaction at atmosphere were obtained, including the ionic collision cross sections, diffusion coefficients, collision rate constants, and the ionic radii under the hard-sphere model approximation.
文摘Plasma processes are among the emerging technologies for volatile organic compounds (VOCs) abatement[1]. Both thermal plasmas and non-equilibrium plasmas (cold plasmas) are being developed for VOCs cleanup[2,3]. Particularly, pulsed corona discharges offer several advantages over conventional VOCs abatement techniques[4-7]. To optimize the existing technology and to develop it further, there is need to understand the mechanisms involved in plasma chemical reactions. Furthermore, it is strongly desirable to be able to predict the behavior of new VOCs in non-equilibrium plasma environment from the data known for a few representative compounds. Pulsed corona discharge technique is introduced here with citation of relevant literature. Fundamental principles, useful for predicting the VOCs' decomposition behavior, have been worked out from the published literature. Latest developments in the area, targeted to minimize the energy losses, improve the VOCs destruction efficiency and reduce the generation of unwanted organic and inorganic by-products, are presented.
文摘The welding fume has significant effects on the weld workers＇ health. In order to overwhelm the shortcomings of the control measures of the welding fume, the research of the purifying of welding fume on the spot was carried out. The purifying device was designed. The relationship between the corona discharge voltage and the purifying efficiency was investigated through experiments with different needle electrode numbers, different ring electrode numbers and different needle-plate distances. The results show that 5-needle double-ring electrode has the best efficiency; the purifying efficiency is increase with the lessening of the needle-plate distance and the increase of the discharge voltage. Using 5-needle double-ring electrode, the purifying efficiency reaches its maximum value 97.9% while the needle-plate distance is 6 cm, the discharge voltage is -35 kV. The purifying device has an excellent purifying effect on the welding fume.
基金Project supported by the National Basic Research Program (973) of China (No.2006CB200303)the Chinese-Slovak Scientific and Technological Cooperation Program (No.2010DFA92020)the China Postdoctoral Science Foundation (No.20100471698)
文摘The naphthalene decomposition in a corona radical shower discharge (CRS) was investigated, with attention paid to the influences of voltage and initial naphthalene density. The OH emission spectra were investigated so as to know the naphthalene decomposing process. The by-products were analyzed and a decomposing theory in discharge was proposed. The results showed that higher voltage and relative humidity were effective on decomposition. The initial concentration affected the decomposing efficiency of naphthalene. When the initial naphthalene density was 17 mg/m3, the decomposition rate was found to be 70% under 14 kV. The main by-products were carbon dioxide and water. However, a small amount of carbonic oxide, 1,2-ethanediol and acetaldehyde were found due to the incomplete oxidization.
