Peracetic acid (CH3C(O)OOH, PAA)-based heterogeneous advanced oxidation process (AOP) has attacked intensive interests due to production of various reactive species. Herein, Co(OH)2 nanoparticles decorated biochar (Co(OH)2/BC) was fabricated by a simple and controllable method, which was used to degrade tetracycline hydrochloride (TTCH) in water through PAA activation. The results indicated that 100% TTCH (C0 = 10 µmol/L) degradation efficiency was realized within 7 min at pH 7, with a high kinetic rate constant (k1) of 0.64 min−1 by the optimized Co(OH)2/BC. Material characterizations suggested that Co(OH)2 nanoparticle was successfully decorated on biochar, leading to more active sites and electronic structure alteration of biochar, thus greatly promoting the catalytic cleavage of PAA for radicals production. Then, the reactive oxygen species (ROS) quenching experiments and electron paramagnetic resonance (EPR) analysis demonstrated the key species were alkoxyl radicals (R–O•, mainly CH3CO2• and CH3CO3•), HO• and 1O2 in this system. Besides, density functional theory (DFT) calculation on Fukui index further revealed that the vulnerable sites of TTCH and three possible degradation pathways were proposed. This study can provide a new strategy for synthesis functional materials in PAA activation AOPs for removal of antibiotics in water.
Sulfadiazine (SDZ), as a broad-spectrum pharmaceutical antibiotic, has drawn extensive attention owing to its wide application and persistence. Photocatalytic oxidation has been considered as a high-efficiency and environment-friendly technology for degrading organic contaminants. A novel BiOI/UiO-66 p-n heterojunction (BiU-x) was fabricated via the in-situ deposition of p-type BiOI nanoplates on n-type UiO-66 octahedrons with the aid of a controlled precipitation method. The optimizing BiU-9 heterojunction exhibited a remarkably enhanced photocatalytic efficiency in removing SDZ, in which the SDZ (5 mg/L) removal efficiency over BiU-9 (0.5 g/L) reached nearly 100 % within 90 min of visible light irradiation. The influence of some important environmental factors (e.g., photocatalyst dosage, pH, co-existing inorganic anions and real sunlight irradiation) were systematically investigated. Such improvement mechanism should be assigned to the following three factors. Firstly, the introduction of narrow gap semiconductor BiOI effectively improved photo adsorption capacity. Secondly, benefiting by the large specific surface area, the involvement of UiO-66 contributed to boost the surface active sites. Most importantly, an internal electric field at the contact interface between UiO-66 and BiOI accelerated the separation of photo-generated electrons and holes. Furthermore, ·O2− and photo-generated holes were identified as the dominating reactive species accounting for the SDZ removal. The decomposition pathways of SDZ and ecotoxicities of the intermediates were analyzed via combing with LC-MS/MS and T.E.S.T theoretical calculation. This work may provide an alternative way for enhanced photocatalytic performance of MOF-based materials through construction of p-n heterojunction with bismuth-based semiconductors.
In this study, an integrated treatment system was proposed and applied in situ, including detention tank, multistage constructed wetlands (CWs) and wastewater treatment plants (WWTPs), preventing nutrients flowing into Dianchi Lake, in which the treatment performance of multistage CWs were evaluated principally. Results skillfully realized the bypass purification of upstream river at dry reasons, as well as the effective management and treatment of the collected diffuse pollution at rainy reasons. The purified water flowing into water bodies could satisfy the Grade III of environmental quality standards for surface water in China with the average effluent concentrations of COD, NH4+-N, TN and TP decreased to 10 (51.2-72.7%), 0.5 (67.2-83.0%), 1.0 (71.2-79.6%) and 0.15 (72.3-89.4%) mg L-1, respectively. High-throughput sequencing results indicated that the application of poly-3-hydroxybutyrate-cohyroxyvelate-sawdust (PS) blends could enrich norank\_f\_Anaerolineaceae (7.95%) and Bradyrhizobium (10.2%), which were distinct from the dominant genera of Pleurocapsa (13.0%) in gravel -based CWs. Functional genes and metabolism analysis uncovered that the heterotrophic denitrification was the main pathway of nitrogen removal with the abundance of genes encoding TCA cycle, glycolysis and deni-trification process up-regulated. In addition, molecular ecological network (MEN) analysis suggested the deni-trification genes were positively correlated with the predominant microbes in PS-based CWs, favorable for denitrifiers to transfer and utilize electron donors during denitrification process. This study proved that the developed PS blends as carbon supplies in CWs and the proposed integrated treatment system are effective methods for watershed management, providing valuable reference to low-pollution wastewater treatment in practical engineering projects.
Interfacial modulation of catalysts for constructing active sites can greatly promote its catalytic activity, while the mechanism on reactive species production at different interfaces still needs to be revealed. In this study, Zr-S4 active sites were usefully constructed on ZnIn2S4 nanosheets, which effectively modulated the reaction interface and band structure, thus boosting the photocatalytic activity. The optimized material (Zr1.2-ZIS) showed a ∼3-fold kinetic rate constant for photocatalytic degradation of tetracycline compared with the pristine ZnIn2S4. Moreover, TC underwent a different degradation pathway over the modified catalyst due to regulation of reactive species after photo-activation. The Zr-S4 centers were energetically favorable for activating O2 into •O2- and •OH, as a more reactive d-band electron was obtained and the adsorption of •O2- as well as its further conversion into •OH was promoted. Theoretical calculations on Fukui index and toxicity also confirmed the dramatical toxicity reduction during TC degradation by Zr1.2-ZIS.
In the context of China's rapid population aging and internet expansion, this study examines the impact of information and communication technologies on the of older adults’ health. Using the China Health and Retirement Longitudinal Study 2011–2018, we find that internet access improves older adults' self-reported health, mental health, and activities of daily living (ADL). Further investigations provide evidence for several underlying mechanisms, including improving social participation, promoting healthy behaviors, and encouraging intergenerational interactions. Heterogeneity analyses show that disadvantaged groups, such as those with any ADL difficulty and without social participation or a spouse, benefit more from internet access.
Despite growing attention to Internet activity as a social determinant of depression in adolescents, few studies have focused on its diverse effects on depressive symptoms. Using data from the 2020 China Family Panel Study, this study employed logistic regression analysis to examine how Internet activity affects depressive symptoms in adolescents in China. The results indicated that adolescents with longer online duration using mobile phones tended to have higher levels of depression. Adolescents who engaged in online activities related to games, shopping, and entertainment had more severe depressive symptoms, but their time spent on online learning was not significantly associated with their level of depression. These findings suggest a dynamic link between Internet activity and adolescent depression and offer policy implications for addressing depressive symptoms in adolescents. Specifically, Internet and youth development policies and public health programs during the COVID-19 pandemic should be designed based on a comprehensive account of all aspects of Internet activity.
As global climate change intensifies, programs to promote green energy innovation are becoming increasingly urgent for humanity. However, academic debate on whether to prioritize industrial or regional policies continues, detracting the focus from programmes to promote green energy innovation. Using data from 3456 listed companies in China in 2020, this study aims to test intra-industry and spatial spillovers to provide empirical evidence to resolve the academic debate and investigate the impact of urban digital finance on corporate green energy innovation to assess the effectiveness of urban policies. Results show that firms' green energy innovations have significant intra-industry spillovers, but no significant spatial spillovers. Moreover, urban digital finance contributes significantly to green energy innovation. The impact of urban digital finance on green energy innovation varies by a firm's nature, internal controls, and external audits. Therefore, this study proposes a multilevel ecosystem for green energy innovation that theoretically supports a comprehensive and systematic understanding of corporate green energy innovation and guidelines for the precise implementation of policy portfolios.
Lexical databases are essential tools for studies on language processing and acquisition. Most previous Chinese lexical databases have focused on materials for adults, yet little is known about reading materials for children and how lexical properties from these materials affect children’s reading comprehension. In the present study, we provided the first large database of 2999 Chinese characters and 2182 words collected from the official textbooks recently issued by the Ministry of Education (MOE) of the People’s Republic of China for most elementary schools in Mainland China, as well as norms from both school-aged children and adults. The database incorporates key orthographic, phonological, and semantic factors from these lexical units. A word-naming task was used to investigate the effects of these factors in character and word processing in both adults and children. The results suggest that: (1) as the grade level increases, visual complexity of those characters and words increases whereas semantic richness and frequency decreases; (2) the effects of lexical predictors on processing both characters and words vary across children and adults; (3) the effect of age of acquisition shows different patterns on character and word-naming performance. The database is available on Open Science Framework (OSF) (https://osf.io/ynk8c/?view_only=5186bd68549340bd923e9b6531d2c820) for future studies on Chinese language development.
Shale is featured by nanometer pores and ultralow permeability. Enhancing shale oil recovery after primary production is challenging as a result of the low injectivity of water. CO2 could be a promising injection fluid to enhance shale oil recovery for its high mobility in porous media and mixability with hydrocarbons. Fluid behaviors in the nanometer pores of shale reservoirs deviate from those in the micrometer pores of conventional reservoirs. The previous understanding of CO2 displacement and sequestration in conventional reservoirs is not completely applicable to shale reservoirs. In this review, we analyzed research advances in CO2 interactions with reservoir fluids and shale rocks at the microscopic level. We delineated recent progress in interpreting phase behavior, mass transfer of the CO2–oil system confined in nanometer pores, and reshaping of CO2-induced mineralization in shale porous media. We also discussed limitations and future directions for studying CO2 injection in shale reservoirs, from the experimental scope, theoretical analysis, and field application.