PubMed · 9508599
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
T Yamayoshi. 1997. [Simple testing methods for environmental pollutants].. https://pubmed.ncbi.nlm.nih.gov/9508599/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Chloroform (CHCl3) is a short-lived ozone-depleting substance not currently regulated under the Montreal Protocol. Due to the unique meteorological conditions in East Asia, CHCl3 emitted in this region has a greater potential to reach the stratosphere and contribute to ozone depletion. As an essential component of national CHCl3 emissions, southeastern China has attracted increasing attention. However, long-term observational data in this region remain relatively scarce, with no updates since 2020. In this study, we continuously measured atmospheric CHCl3 concentrations at a remote monitoring station in southeastern China from 1 June 2023 to 31 May 2025. Frequent concentration enhancements were observed during the monitoring period, with mixing ratios ranging from 9.3 to 134.1 ppt and an average value of 36.8 ± 19.7 ppt. Back-trajectory analysis indicated that air masses associated with elevated CHCl3 levels primarily originated from coastal industrial provinces in eastern China. Using the Potential Source Contribution Function and Concentration Weighted Trajectory methods, we identified the Yangtze River Delta (Jiangsu, Anhui, and Zhejiang Provinces) and Jiangxi Province as dominant source regions. Emissions of CHCl3 in southeastern China were estimated using the Tracer Ratio Method to be approximately 30.1 ± 5.3 Gg/yr from 2023-06-01 to 2025-05-31, indicating overall stability relative to earlier estimates and no apparent upward trend. These findings provide updated insights into the current status of CHCl3 emissions in southeastern China and highlight the need for continued monitoring and emission assessment of CHCl3 in East Asia, given its unregulated status and implications for ozone layer recovery.
A bubbling fluidized bed reactor was used as a desulfurization apparatus in this study. The height of the bed was 2.5m, and the inner diameter was 9cm. The bed materials were calcium sorbent and silica sand. The effects of the operating parameters of the flue gas desulfurization including relative humidity, temperature, superficial gas velocity, and the particle size of calcium sorbent on SO2 removal efficiency and calcium sorbent conversion and attrition rate in the fluidized bed were investigated. It was found that the temperature effect in our system was negligible from 40 to 65 degrees C. A higher relative humidity had a higher calcium conversion and a higher sulfur dioxide removal efficiency. Moreover, a smaller particle size of calcium sorbent had a lower calcium conversion in the cyclone but a higher sulfur dioxide removal efficiency. A lower superficial gas velocity resulted in a higher sulfur dioxide removal efficiency and a higher calcium conversion, thus, the total volume of the flue gas treated was maximum near the minimum fluidization velocity. Finally, an attrition rate model proposed in this study could predict the elutriation rate satisfactorily.
The dc corona was studied as an alternative for NO oxidation in a two-stage chemical scrubber. The dc corona plasma reactor completely oxidized 150ppm of NO to NO2 in an air stream. The NO2 was further oxidized at a higher voltage. For some cases, the NO2 in the effluents of the plasma reactor was absorbed quantitatively by a caustic sodium sulfite aqueous solution in a 2l bubble column gas absorber. The outlet concentrations of both NO and NO2 from the plasma-scrubber combination system (corona-induced chemical scrubber) were below the detection limit of the chemiluminescent NOx analyzer.