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Hayes posted an update 9 months, 1 week ago
Lacking consolidated qualitative and quantitative analysis methods of Al nanoclusters in aqueous, the distributions and concentrations of each Al species could not be revealed with single method before or after coagulation, which limited the development of environmental Al clusters control. As the ESI-MS applied in the inorganic cluster’s identification tentatively, the deficient identification of Al species could be analyzed qualitatively and quantitatively with mass spectrum directly. Although many studies have applied the ESI-MS to analyze Al species in aqueous, the experimental conditions were not compared and not reached an agreement. Therefore, this work is the first study to review the methodology developments of ESI-MS in Al identification and to summarize the qualitative and quantitative analysis promoted by ESI-MS. The principle and rationality of quantitative ESI-MS method were inducted and discussed from the prospects of resolving mass spectrum assignment and transforming species in ionization. The qualitative ESI-MS results in previous studies were also analyzed by quantitative ESI-MS analysis in this work. The quantitative Al species results are accordant with the distribution results concluded via Al-Ferron and 27Al NMR methods. The identification principles and instrumental parameters were summarized and unified, which would give hints to further methodological applications and modifications. This study puts forward the further possibilities and prospects of ESI-MS applied in the transformation and in-situ identification of Al13 nanocluster in aqueous.Odor emissions from wastewater treatment plants (WWTPs) have always been a public concern. In this work, the physico-chemical, olfactometric and textural characterization of granular active carbon (GAC) used by an urban WWTP as a deodorization system, as well as the chromatographic quantification of the retained odoriferous compounds, have been carried out. These techniques have allowed an integral evaluation of the contaminated GAC and the characterization of the retained gaseous emission from four different stages of the wastewater treatment (pretreatment header GAC-1; sand and fat removal GAC-2; sludge thickening GAC-3; sludge dehydration GAC-4). A larger amount and variety of retained odoriferous compounds were found in GAC samples from the wastewater line deodorization (GAC-1 and GAC-2) after the same operation time (one year), GAC-1 being the adsorbent bed that retained the highest mass of volatile compounds (approximately 150μg/g GAC). Furthermore, some variables such as the removed specific odor concentration and free micropore volume were inversely correlated (R2=0.9945). The analysis of odor contribution showed that sulfur-containing compounds were the major odor contributors (61-97%). However, hydrogen sulfide cannot be considered a key odorant in this particular WWTP, since the elimination of this compound does not reduce the significant contribution of other (organic) sulfur compounds to the global odor (especially dimethyl disulfide). Consequently, multi-technical analysis might be a suitable alternative to better understand odor removal by GAC adsorption.Biochar is a carbon-rich material that can be obtained from pyrolysis of solid waste (e.g., agricultural solid waste and sludge from wastewater treatment plants). Biochar features low cost, large specific surface area, and strong adsorption capacity. New biochar composites can be produced via modification and loading of nano particles onto biochar. Biochar can contribute to the dispersion and stabilization of nano particles. In addition, nano particles can increase the number of surface-active sites, which improves the physicochemical properties of the material. Biochar and biochar composites have been applied widely in wastewater treatment, and have significantly enhanced the treatment performance of Fenton-like processes (activation of hydrogen peroxide and persulfate) as an advanced oxidation process for organics removal and wastewater decontamination. This paper reviews the preparation methods for biochar and biochar composites to systematically analyze the influential factors on the preparation process. The paper also comprehensively reviews the mechanisms by which biochar removes different organic pollutants. However, due to the vast number of different biochar feedstocks and their preparation methods, it is difficult to compare the properties of one biochar to another. EPZ015866 Guidance if provided for the application of biochar and biochar composites for wastewater decontamination.New energy vehicles (NEVs) are considered as the potential measure to address urban air pollution, and the Chinese government has launched a pilot subsidy scheme to improve its market penetration. We explored the environmental effects of subsidy on urban air pollution from the extensive and intensive margins and formulated a detailed panel dataset, covering 286 cities in China over the years 2006-2018. Moreover, the PSM-DID method and the instrumental strategy are used to confirm the robustness and validity of empirical results on the basis of comprehensive analysis of potential endogenous issues. The results indicate that the implementation of NEVs subsidy policy could significantly improve urban air quality in general, and as the subsidies scale increased by 1%, air pollution level will be reduced by about 0.15%. Then, from the perspective of the dynamic effect of subsidy, it not only has remarkable current environmental effect, but also an effective technology route in the long run. Simultaneously, compared with traditional intervention tools, subsidies enhance the diffusion of NEVs, reduce emissions of air pollutants while meeting residents’ travel needs, and thus achieve incentive compatibility, which is the micro-foundation of environmental improvement. Nonetheless, we cannot simply believe the assertion that NEVs subsidy has positive environmental benefits to each region, as the non-clean generation of electricity in some areas will offset the potential environmental benefits. Additionally, the accelerated phase-out of NEVs subsidies at this stage may cause negative externalities of economy and environment, resulting the deadweight loss of industrial dividends accumulated in the early period. Based on above findings, governments should implement more flexible stimulus policies consistent with NEVs industry developments, rather than drastically reducing subsidies, while paying close attention to decarbonization of energy production stage.