Mechanical insights into desulfurization by peroxymonosulfate oxidation via a non-reactive oxygen species pathway.

Air pollution by sulfur dioxide (SO) remains a pressing concern for both the environment and human health. Desulfurization enhanced by persulfate based advanced oxidation processes (PS-AOPs) has been proven to be a feasible method. However, the inherent contradiction between the rapid diffusion mass transfer of SO in the "gas-liquid-gas" phase and the limited lifespan of reactive oxygen species (ROS) can not be ignored.

Low oxygen levels with high redox heterogeneity in the late Ediacaran shallow ocean: Constraints from I/(Ca + Mg) and Ce/Ce* of the Dengying Formation, South China.

Most previous studies focused on the redox state of the deep water, leading to an incomplete understanding of the spatiotemporal evolution of the redox-stratified ocean during the Ediacaran-Cambrian transition. In order to decode the redox condition of shallow marine environments during the late Ediacaran, this study presents I/(Ca + Mg), carbon and oxygen isotope, major, trace, and rare earth element data of subtidal to peritidal dolomite from the Dengying Formation at Yangba, South China. In combination with the reported radiometric and biostratigraphic data, the Dengying Formation and coeval successions worldwide are subdivided into a positive δ C excursion (up to ~6‰) in the lower part (~551-547 Ma) and a stable δ C plateau (generally between 0‰ and 3‰) in the middle-upper part (~547-541 Ma).

Rapid Vanadium Extraction from Roasted Vanadium Steel Slag via a HSO-HO System: Process and Mechanism.

A HSO-HO system was developed to enhance the efficacy of vanadium extraction from roasted vanadium steel slag. The optimum parameters and the behavior of vanadium extraction were investigated systematically. When 1 mL of HO per gram of vanadium slag was added to a leaching mixture at 50 °C, along with 30% HSO, 80.

Enhanced biological phosphorus removal from wastewater by current stimulation coupled with anaerobic digestion.

The integrated wastewater discharge standard for phosphorus has become increasingly strict. In this study, a synergetic current stimulation system coupled with anaerobic digestion was used to enhance phosphorus removal from wastewater. The effects of current intensity, pH, and methane (CH) synthesis on phosphorus removal were investigated.

Effects of reactive oxygen species scavengers on thermophilic micro-aerobic digestion for sludge stabilization.

In thermophilic digestion systems, sludge stabilization may be adversely impacted by high concentrations of ammonia nitrogen or the rapid accumulation of fatty acids; however, few studies have focused on the mitigation of the inhibition of reactive oxygen species (ROS). In this study, fulvic acids or tea polyphenols were introduced to a thermophilic digestion system and the effects of ROS scavengers on sludge stabilization were investigated. As fulvic acids or tea polyphenols were added to sludge, they reacted with metal cations, such as Cu and Zn, to form stable complexes that enabled active metal ions to be transported into cells to enhance the oxidase activities.

Effects of pH on the biodegradation characteristics of thermophilic micro-aerobic digestion for sludge stabilization.

For a thermophilic micro-aerobic digestion (TMAD) system, the pH is closely related to the production of short-chain fatty acids and ammonia release. Batch experiments at different pH values were carried out to elucidate the effects of pH on the biodegradation characteristics of TMAD processes. A digester at pH 9.

Impacts of ammonia nitrogen on autothermal thermophilic micro-aerobic digestion for sewage sludge treatment.

The concentration of ammonia nitrogen is relatively high during autothermal thermophilic micro-aerobic digestion (ATMAD), which could significantly affect the sludge stabilization. This paper aims to investigate the impacts of ammonia nitrogen on ATMAD process, batch experiments were carried out with dosage of certain amount of NHHCO into digestion system. The total ammonia nitrogen (TAN) was considered as a suitable indicator to characterize the ammonia inhibition.

Progressive Indosinian N-S deformation of the Jiaochang structure in the Songpan-Ganzi fold-belt, Western China.

Integrated field data, microstructural and three-dimensional strain analyses are used to document coaxial N-S shortening and southward increase in deformation intensity and metamorphism at the Jiaochang structure. Two episodes of deformation (D1,D2) with localized post-D2 deformation have been identified in the area. The first deformation (D1) episode is defined by a main axial-plane of parallel folds observable on a micro- to kilometer-scale, while the second episode of deformation (D2) is defined by micro-scale metamorphic folds, associated with E-W oriented stretching lineation.

The one-stage autothermal thermophilic aerobic digestion for sewage sludge treatment: stabilization process and mechanism.

Batch experiment was carried out in a simulated thermophilic aerobic digester to investigate the digestion process of one-stage autothermal thermophilic aerobic digester and to explore the sludge stabilization mechanism. Volatile solids removal was 38.4% at 408 h and 45.

Isolation, identification and utilization of thermophilic strains in aerobic digestion of sewage sludge.

Two representative thermophilic bacterial strains (T1 and T2) were isolated from a one-stage autothermal thermophilic aerobic digestion pilot-scale reactor. 16S rRNA gene analysis indicated that they were Hydrogenophilaceae and Xanthomonodaceae. These isolated strains were inoculated separately and/or jointly in sewage sludge, to investigate their effects on sludge stabilization under thermophilic aerobic digestion condition.

Chemical and microbial changes during autothermal thermophilic aerobic digestion (ATAD) of sewage sludge.

Autothermal thermophilic aerobic digestion (ATAD) is a promising process for sewage sludge stabilization. Batch experiments were conducted on sewage sludge collected from a municipal wastewater treatment plant in Shanghai, China, to evaluate the effectiveness of the ATAD system by determining changes in volatile suspended solids (VSSs) and to study its microbial diversity by denaturing gradient gel electrophoresis of 16S rRNA gene sequences amplified by PCR. The digestion system achieved rapid degradation of the organic substrate at 55 degrees C.