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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] Troposphere ozone, which is from secondary formation processes, has been increasing dramatically during the last decades in China, inducing high health risks. In this study, temporal and spatial distribution of O3 was studied among 13 sites of three cities during 2014–2016. The objectives were to clarify the characteristics of the ambient pollution of O3 under the influence from other pollutants and meteorological parameters and the health outcomes from exposure to O3. The concentrations of O3 during summer were much higher than those during winter, and the concentrations in downtown areas were higher than in rural or mountain areas. PM2.5, NO2, SO2, and wind speed (WS) were negatively correlated with O3, and CO, temperature (T), and relative humidity (RH) were positively correlated with O3. In multivariable analysis, two separate factors—solar radiation and atmospheric diffusion status, affected the O3 levels. The concentrations of O3 reached the highest level at 15:00 and the lowest value at about 6:00–8:00, with the similar trend to T and WS, and opposite to RH. According to the dose-response model, relative risks (RRs) and population attributable fractions (PAFs) with confidence intervals (CIs) for chronic obstructive pulmonary disease (COPD) from exposure to O3 were 1.0612 (CI 1.0607–1.0616) and 5.32% (CI 5.29–5.36%), respectively, attributable to 2000 deaths in Zhejiang Province in 2014.
[en] Highlights: • A copula-based flexible-stochastic programming (CFSP) method is proposed. • CFSP can handle multiple uncertainties and reflect interaction of random variables. • It is applied to planning RES of the urban agglomeration of Beijing and Tianjin. • Scenarios of various joint- and individual constraint-violation levels are selected. • Results can provide in-depth analysis for identifying desired decision schemes. - Abstract: In this study, a copula-based flexible-stochastic programming (CFSP) method is developed for planning regional energy system (RES). CFSP can deal with multiple uncertainties expressed as interval values, random variables and fuzzy sets as well as their combinations employed to objective function and soft constraints. It can also reflect uncertain interactions among random variables through using copula functions even having different probability distributions and previously unknown correlations. Then, based on the developed CFSP approach, a CFSP-RES model is formulated for planning RES of the urban agglomeration of Beijing and Tianjin (China). Results disclose that uncertainties existed in the system components have significant effects on the outputs of decision variables and system cost, and the variation of system cost is reached 16.3%. Results also reveal that air pollutant emissions can be mitigated if the urban agglomeration can co-implement renewable energy development plans (REDP) over the planning horizon, with the reductive rates of [3.3, 7.6] % of sulfur dioxide (SO2), [2.7, 4.1] % of nitrogen oxides (NOx) and [7.0, 11.5] % of particulate matter (PM10). Compared to joint-probabilistic chance-constrained programming (JCP), the CFSP method is more effective for handling multiple random parameters associated with different probability distributions in which their correlations are unknown. Thus, it is not limited to some unjustified assumptions and can be applied to a wider range of problems than previous studies. The findings are helpful to explore the influence of interaction among random variables on modeling outputs and provide in-depth analysis for identifying desired decision schemes for planning RES.
[en] Highlights: • A compact and efficient gas reactor based on a point discharge microplasma (PD). • Gaseous oxidation reaction from H2S to SO2 with a high efficiency of 95%. • Chromatography-free and rapid speciation analysis for sulfide and sulfite. • Simple operation with PD on/off for sampling into a fluorescence spectrometer. - Abstract: A low temperature plasma integrating the merits of small size, simple operation and rich active particles has good performance in analytical chemistry. In this work, a point discharge microplasma was used as a reactor to facilitate the gaseous conversion reaction from H2S to SO2 with an excellent efficiency as high as 95%. By coupling this reactor with a fluorescence spectrometer, the speciation analysis of sulfide and sulfite was achieved in a simple, chromatographic separation-free, time-saving and practical way. Specifically, with the discharge off, only sulfite was quantified; with discharge on, both sulfide and sulfite were quantified; and with a simple subtraction, the speciation analysis could be easily attained. By the acidification process, a limit of detection of 7.7 µM by the proposed method was obtained for both sulfide and sulfite in aqueous medium, and this method was successfully utilized to analysis of real samples.
[en] Highlights: • A new corrosion prediction model incorporating the effects of multiple dynamic environmental factors is proposed. • The multi-parameter method is accurate to describe the dependence of humidity on temperature. • Correction factors calculated with the new model are close to the real value. • The nonlinear accelerating effects of humidity and temperature are remarkable. - Abstract: This paper studies the effects of relative humidity, temperature, sulphur dioxide, and chlorides on the short-term corrosion behavior in the dynamic environment. A multi-parameter method is developed to characterize the statistical distributions of the environmental factors with high accuracy. The results suggest that TOW (time-of-wetness) should be replaced by temperature and relative humidity distributions. A corrosion model which is combined with physical and empirical knowledge of corrosion is presented and gives more accurate corrosion estimation than using the mean values of the environmental factors and fitting them independently. It is also demonstrated that relative humidity is the most influential factor on corrosion and temperature is secondary. The nonlinearity of their accelerating effects on corrosion rate are remarkable and should be considered in the daily dynamic environment. Sulphur dioxide and chlorides are important accelerating variables and their nonlinear accelerating effects are less significant.
[en] An indigenously developed DC electron accelerator is currently operating at the Electron Beam Centre, Kharghar at 1MeV energy and 5 kW power. Experiments were conducted on simulated flue gas for treatment of SO2 and NO at a flow rate of 500 Nm3/hr. Flue gas is simulated by burning LPG in furnace and diluted air is mixed with the combustion air to get desired temperature and flow rate. This hot air stream is injected with NO and SO2 from cylinders by means of mass flow controllers to achieve the desired concentrations of the pollutants. This simulated flue gas passes through 80 meter long mild steel duct of cross-section 113 x 113 mm with a velocity of about 10 m/s. Some water-loading experiments were also tried by heating the duct with LPG. A relative humidity of 25% was achieved at 70 °C in the duct by injecting water at 13 lph. Further experiments are in progress to understand the process better and optimize the removal efficiency
[en] First-principles calculations have been carried out to investigate the adsorption properties of SO2 molecules on nitrogen-doped TiO2 anatase nanoparticles using the density functional theory method to fully exploit the gas-sensing capabilities of TiO2 particles. For this purpose, we have mainly studied the adsorption of the SO2 molecule on the dangling oxygen atom and doped nitrogen atom sites of the TiO2 nanoparticles because these sites are more active than other sites in the adsorption processes. The complex systems consisting of the SO2 molecule positioned toward the undoped and nitrogen-doped nanoparticles have been relaxed geometrically. The results presented include structural parameters such as bond lengths and bond angles and energetics of the systems such as adsorption energies. The electronic structure and its variations resulting from the adsorption process, including the density of states, molecular orbitals, and the charge transfer, are discussed. We found that the adsorption of the SO2 molecule on the nitrogen-doped TiO2 nanoparticles is energetically more favorable than the adsorption on the undoped ones. These results thus provide a theoretical basis for the potential applications of TiO2 nanoparticles in the removal and sensing of SO2 and give an explanation for helping in the optimization of improved gas removers and sensor devices. (author)
[en] Since the Clean Air Act Amendment (1990), the markets of tradable emission permits are becoming increasingly attractive. Very few works on the functioning of these markets have analyzed the participation of citizens in order to buy and retire emissions permits. This dissertation aims to study the effects of allowing citizens to participate in markets of tradable emission permits. In the first chapter, we show that when the pollution cap is strictly greater than the optimal one, citizen's participation is socially beneficial and never socially harmful, even in the presence of free-riding. In the second chapter, based on operating pollution markets in the US and Europe, we highlight the emergence of a demand to purchase and cancel emissions permits. In the third chapter, we show how it is possible to partly solve the free rider problem by subsidizing the citizen's demand. Moreover, we argue that an ethics based on the freedom and the sovereignty of citizens commands to allow citizens participation in pollution market. In the fourth chapter, we focus on citizen's participation in pollution markets with a regional pollution model. Such an implication depends on the value of transfer coefficients. (author)
[fr]Depuis l'amendement du Clean Air Act (1990), les marches d'echange de permis d'emissions connaissent un succes grandissant. Un aspect peu etudie de leur fonctionnement est la participation des citoyens pour acheter et retirer des permis d'emissions. Cette these vise a etudier l'opportunite d'ouvrir le marche de permis aux citoyens et a analyser les implications de leur participation. Dans un premier chapitre, nous revenons sur le debat taxe versus marche. Nous montrons que lorsque le plafond de pollution est strictement superieur au plafond de pollution optimal, la participation des citoyens est socialement benefique et n'est jamais socialement dommageable, meme en presence de comportement de passager clandestin. Dans le deuxieme chapitre, a partir d'exemples de marches mis en place aux etats-Unis et en Europe, nous mettons en evidence l'emergence d'une demande de retrait de permis de la part des citoyens et des ONG environnementales. Dans le troisieme chapitre, nous montrons qu'il est possible de lutter efficacement contre le probleme de passager clandestin en subventionnant la demande de retrait de permis des citoyens. Par ailleurs, l'intervention d'une ethique basee sur un postulat de liberte et de souverainete conduit a recommander l'autorisation des citoyens a participer au marche. Enfin, le dernier chapitre analyse la participation des citoyens dans le cadre d'un modele de pollution regionale et apprecie leur implication selon la valeur des parametres des coefficients de transferts de pollution. (auteur)
[en] The electrochemical behavior of amorphous and nanocrystalline soft magnetic Fe79P13Si5V3 alloy in a 0.1 M Na2SO4 solution has been studied. Mössbauer studies show that the electrochemical characteristics of the alloy are comparable with those of an Finemet Fe77Si13B7Nb2.1Cu0.9 alloy, whereas the studied alloy is inexpensive and can be prepared using natural alloy ferrophosphorus containing vanadium and silicon.
[en] Ascending gas is a global phenomenon. It can move upwards along faults or fissures from the interior of the Earth to the surface of the Earth. Seismically active regions near continental plate boundaries are active regions of ascending gas. Based on the results of previous research, abnormal concentrations of SO2, CO2, Rn, He, H2, O2, Ar, N2, and CH4 in ascending gas may be applied to earthquake prediction. In our study, particles carried by ascending gas in ruptures caused by the Wenchuan earthquake have been discovered using a transmission electron microscope. It can be seen that there are far more particles in the ascending gas of ruptures caused by the 2008 earthquake than there are in the ascending gas of the non-seismic Fengguanshan fault or the ascending gas of the soil in Wufeng Town of Jintang County or Yuhe Village of Pengshan County (which represent background areas). The abnormal characteristics of the particles carried by the ascending gas of ruptures also include Cu-, Hg-, and Os-enriched particles. The typical elemental associations are Fe-Mn-Ni-Cr and Pb-Cr. SiO2 particles contain abnormally high contents of impure elements in the form of particles that have been encapsulated by SiO2. This is the first study to report the presence of particles carried by ascending gas in earthquake ruptures. This study represents a new method of earthquake prediction. These particles can provide us with abundant and direct information about earthquake activity, which can be applied to earthquake prediction. Characteristics of the particles in the ascending gas, combined with the concentrations of Hg, SO2, CO2, Rn, He, H2, O2, Ar, N2, and CH4, can be used to develop a more efficient method of earthquake prediction. - Highlights: • Particles carried by ascending gas in ruptures caused by the Wenchuan earthquake have been discovered. • These particles include Cu-enriched, Hg-enriched, and Os-enriched particles. • The typical elemental associations are Fe-Mn-Ni-Cr and Pb-Cr. • The SiO2 particles have abnormally high contents of impure elements in the form of particles encapsulated by SiO2. • The study presents a new method of earthquake prediction.