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[en] The design and metrological characteristics of a photometric gas analyzer for atmospheric sulfur dioxide that is equipped with adsorbing polymer films are considered. It is shown that the device can solve ecological and health safety issues and has small overall dimensions and power consumption.
[en] Vertical profiles of O_3 and SO_2 concentrations were monitored at the Borden Forest site in southern Ontario, Canada from May 2008 to April 2013. A modified gradient method (MGM) was applied to estimate O_3 and SO_2 dry deposition fluxes using concentration gradients between a level above and a level below the canopy top. The calculated five-year mean (median) dry deposition velocity (V_d) were 0.35 (0.27) and 0.59 (0.54) cm s"−"1, respectively, for O_3 and SO_2. V_d(O_3) exhibited large seasonal variations with the highest monthly mean of 0.68 cm s"−"1 in August and the lowest of 0.09 cm s"−"1 in February. In contrast, seasonal variations of V_d(SO_2) were smaller with monthly means ranging from 0.48 (May) to 0.81 cm s"−"1 (December). The different seasonal variations between O_3 and SO_2 were caused by the enhanced SO_2 uptake by snow surfaces in winter. Diurnal variations showed a peak value of V_d in early morning in summer months for both O_3 and SO_2. Canopy wetness increased the non-stomatal uptake of O_3 while decreasing the stomatal uptake. This also applied to SO_2, but additional factors such as surface acidity also played an important role on the overall uptake. - Highlights: • Application of a modified gradient-method for quantifying dry deposition is demonstrated. • A five-year dry deposition database is developed for O_3 and SO_2 over a mixed forest. • Canopy wetness enhances non-stomatal O_3 uptake while inhibits stomatal uptake. • High surface acidity reduces SO_2 dry deposition. - Capsule: A five-year dataset of O_3 and SO_2 dry deposition velocities was generated from concentration gradient measurement data using a modified gradient method.
[en] We study the dynamical entanglement of vibrations, intramolecular energy transfer and coherence properties in triatomic molecular systems based on discrete self-trapping theory. O3 and SO2 samples are employed as typical local-mode (LM) and normal-mode molecules, respectively. It is demonstrated that the LM molecule prepared in a LM characteristic state is much more suitable to realize quantum computation. In addition, by introducing a section of entanglement and energy transfer, we investigate the relationship between the two quantities generally. The dynamics between entanglement and energy transfer can reveal a good synchronism under some conditions. Moreover, the intramolecular coherence properties presented by the coherence visibility are discussed in some cases. (paper)
[en] Various studies have illustrated that exposure to ambient air pollution has negative impacts on health. However, little evidence exists on the effects of ambient air pollution on circulatory mortality in Xi’an, China. This study aims to investigate and ascertain the association between short-term exposure to ambient air pollutants and circulatory mortality in Xi’an, China. Daily average concentrations of PM2.5, SO2, and O3, meteorological data (temperature and relative humidity) and daily counts of circulatory mortality were obtained between January 2014 and June 2016. Mortality was stratified by gender and age group (≤ 64 years and ≥ 65 years). A generalized additive model (GAM) with natural splines (NS) was constructed to analyze the relationship between ambient air pollutants and daily circulatory mortality. There were 57,570 cases of circulatory mortality, with cerebrovascular and ischemic heart diseases accounting for 48.5% and 43.5%, respectively. All ambient air pollutants displayed different seasonal patterns. In the single pollutant model, 10 μg/m3 increase in 2-day moving average concentrations of PM2.5, SO2, and O3 was associated with relative risk of 1.288(1.198, 1.388), 1.360(0.877, 2.331), and 1.324(1.059, 1.705) in circulatory mortality, respectively. After adjusting for collinearity in the multi-pollutant model, the effects remained statistically significant. The ≥ 65 years and female sub-groups were associated with a higher risk of circulatory mortality. Short-term exposure to ambient air pollutants plays a pivotal role in the genesis of circulatory mortality in Xi’an. Responses to ambient air pollutants exposure in relation to circulatory mortality are different when analyzed by sub-groups.
[en] The effects of sensing materials, coating methods, diluent gases, and temperature have been studied in detail to make a quartz crystal microbalance based adsorption sensor system for detecting gases. In particular, sensor elements for detecting NO2 and SO2, that are known as major air pollutants, have been prepared by coating two different polymers, polypyrrole and poly(3,4-ethylenedioxy thiophene). The sensor elements prepared in this work have high sensitivity and selectivity for NO2 and SO2 at ppm level concentrations. It was proven that the sensing characteristics and response rate of the sensing elements are highly dependent on the coating method and the loading mass of sensing materials
[en] The performance of Cytisus striatus in association with different microbial inoculant treatments on the dissipation of the insecticide hexachlorocyclohexane (HCH) was studied. Two soils with different organic matter (A and B soil) content were spiked with 0 or 65 mg HCH kg−1. Plants were either not inoculated (NI), or inoculated with the endophyte Rhodococcus erythropolis ET54b and the HCH-degrader Sphingomonas sp. D4 separately or in combination (ET, D4 and ETD4). Unplanted pots were also established. HCH phytotoxicity was more pronounced in the B soil. Soil HCH concentrations in unplanted pots were similar to initial concentrations, whereas concentrations were reduced after plant growth: by 20% and 8% in A and B soil, respectively. Microbial inoculants also modified HCH dissipation, although effects were soil-dependent. Inoculation with the combination of strains (ETD4) led to a significant enhancement in HCH dissipation: up to 53% in the A soil and 43% in the B soil. -- Highlights: •Effect of microbial inoculants on HCH dissipation was studied in a plant-soil system. •Inoculation of C. striatus with bacterial strains strongly enhance HCH dissipation. •Retention of HCH by organic matter can influence efficiency of HCH phytoremediation. -- The inoculation of Cytisus striatus with a combination of bacterial strains is a promising approach for the remediation of HCH-contaminated sites
[en] Highlights: • The Environmental Kuznets Curve (EKC) has been estimated at the national and the provincial level in China. • There exists aggregation bias in estimating the national level EKC for sulfur dioxide emission. • The local government should play more important role in environmental policy-making. - Abstract: Aggregation bias may lead to a wrongly estimated Environmental Kuznets Curve (EKC), and misguide the policy-makers. This paper aims to test the existence of aggregation bias in the Environmental Kuznets Curve with the sulfur dioxide (SO2) emission. The empirical methods robust to cross-sectional dependence and slope heterogeneity reveals that the estimation of SO2 EKC in China suffers from aggregation bias. The results with the disaggregate data cannot support the EKC estimated at the aggregate level. The finding of aggregation bias has several policy implications. First, the government should not be misled by the false relationship between the pollutant emission and the real GDP per capita at the aggregate level. Second, the local governments should play more important roles in making environmental protection policies since the more disaggregate data can mitigate the aggregation bias. To provide enough incentives to the local government, the Chinese national government should align the interests of the local governments with those of the national government. On the other hand, the findings indicate that China can stick to the policy of encouraging foreign direct investment, openness and financial development since they have not influenced the SO2 emission in China.
[en] A new type of sample preparation device and its reactor for sulfur isotope in sulfide and sulfate experiment is developed. The trial experiment proved that the sample preparation device and its reactor are characterized with good vacuum, easy to use, clean, high efficient and low cost to produce sulfur dioxide of high purity, and the analytical results are accurate and reliable. The device and reactor can fully meet for the analysis on the sulfur isotope in various sulfide and sulfate. (authors)
[en] Sulfur dioxide is a major air pollutant in the environment. Fortunately, the plant purification system can effectively reduce SO2 pollution. However, the effect mechanism of plant purification system for the dynamic evolution of SO2 remains incompletely clear. In this work, inspired by the “Boston ivy,” we successfully designed and constructed a semi-continuous plant system. Subsequently, based on the “vine-like plant” and the “island-like plant,” the semi-continuous plant system and the isolated plant system are selected as the models of plant purification system, respectively. The dynamic evolution of SO2 in the plant systems is investigated using the computational fluid dynamic (CFD) method. It is demonstrated that the dynamic evolution of SO2 is impacted by the plant structure and the flow path ((cg/lg) + (cl/ll)). In the semi-continuous plant system, the strong flow paths with gradually weakened fluctuation are restricted by this special plant structure, the length of flow paths are extended, and more SO2 can be dissolved. In the isolated plant system, the mild flow paths with linear relationship can easily pass through the plants, such that only a little SO2 is dissolved. Overall, the present study opens a new path into the dynamic evolution of SO2 pollution in the plant systems, which helps providing guidance for the designing of plant purification system.
[en] To explore plate separation techniques of Acidithiobacillus ferrooxidans and understand its growth characteristic, strains of Acidithiobacillus ferrooxidans were obtained by separation and purification using 2 : 2 solid medium. And growth characteristics of 5 strains of them were studied. The results showed that 2 : 2 solid medium could be used ideally for separation and purification of Acidithiobacillus ferrooxidans. And the fastest growth rate of Acidithiobacillus ferrooxidans could get at the initial pH value from 2.O to 2.5, the optimal growth temperature was 30 ℃ 9 the initial Fe2+ concentration might be desirable for 4.623 g/L, and the appropriate inoculums' quantity was 10%. There existed growth characteristics differences among different Acidithiobacillus ferrooxidans strains. (authors)