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The hydrogen adsorption and diffusion behaviors on the clean and a series of element doped Zr(0001) surfaces are studied through first-principles calculations. Among the studied doping elements, Cu, Co, Y, and Mg prefer to substitute Zr on the topmost surface layer, Al, Pd, Ir, and Si are favored from topmost layer to several surface layers down, while Mo is not favored. Independent of the substitution energies, Mo, Co, and Ir induce a symmetry-breaking local distortion surface structure. Based on the obtained geometries, it is found that most dopants promote the hydrogen adsorption on their next nearest neighbor sites but hinder it on the nearest neighbor sites. Most of the dopants also promote both the hydrogen diffusion on the surface plane and the hydrogen penetration into the subsurface layers. The results indicate that element doping may facilitate the hydride nucleation in Zr alloys. [Display omitted] • Co, Mo and Ir-doping on Zr(0001) surface induce symmetry-breaking local distortion. • Most dopants promote H adsorption on Zr(0001) in their around area. • Most dopants promote both H diffusion on surface and penetration into subsurface. [ABSTRACT FROM AUTHOR]

Urban parks, a public product and service, can provide ecological, social, cultural, and recreational resources essential for sustainable urban development. Park attributes are valuable indicators for evaluating parks, and park planning and management personnel must consider visitors' perceptions of these attributes. However, previous studies often ignored or underestimated negative attributes, especially in high-rating reviews. Moreover, parks have multiple attributes, rather than a singular one, and there exist potential associations among these attributes. Here, we selected 63 urban parks in Park City, Chengdu, China, as a case study; we used online reviews from Ctrip and Dianping, and Latent Dirichlet Allocation (LDA) combined with a manual coding method to explore visitors' perceptions (positive or negative) of each attribute in each review. Initially, we analyzed how park attributes affected overall dissatisfaction using multiple linear regressions, and counted the positive and negative attributes in each review rating. We then measured the association rules between various attributes and perceptions. We found that both positive and negative attributes (84.12% and 54.86%) mainly appear in high-rating reviews, while low ratings accounted for only 15.69% of negative attributes. Attributes in high-rating reviews were more generalized and had a more significant effect than in low-rating. Additionally, three association rules were identified, including cases where two positive attributes (11 instances), two negative attributes (6 instances), or one negative and one positive attribute appeared together (2 instances), all within the cultural and historical attributes category. This study's outcomes contribute novel insights to the realm of sustainable urban park planning and management. • Negative attributes lead to dissatisfaction in different review rating. • Negative attributes in high-rating reviews are impactful and generalized. • Associations rule between various park attributes. • Combined Latent Dirichlet Allocation with manual coding approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO@NH 2 -MIL-88B has good degradation performance for a variety of organic pollutants. • Simultaneous degradation and removal of multiple organic pollutants by ZMFe-3. • Three degradation pathways of MB were predicted by DFT calculations and LC-MS. • ZnO@NH 2 -MIL-88B forms a fast electron transfer channel. Combining photocatalysts with Fenton technology can improve the catalytic properties of materials and achieve efficient degradation of organic pollutants. However, preparing low-cost catalysts using simple methods remains a challenge. This paper selected a more environmentally friendly and cost-effective semiconductor material, zinc oxide, for the modification of NH 2 -MIL-88B and prepared a new S-scheme heterojunction photo-Fenton catalyst ZnO@NH 2 -MIL-88B (ZMFe-x) by a simple solvothermal method. Moreover, the Zn-O-Fe bonds that were formed between the interfaces enabled a fast channel for the photoelectron transport that was created by photoexcitation from the ZnO conduction band to the NH 2 -MIL-88B valence band. This allowed the ZMFe-x catalysts to have better removal performance for organic pollutants in the photo-Fenton reaction. The dominating role of hydroxyl radicals in the degradation procedure was determined by ESR analysis and free radical trapping experiments, and the degradation mechanisms and pathway of contaminants were predicted by intermediate analysis and DFT calculations. This study provides a stable and effective new strategy for preparing MOFs catalysts for removing various pollutants. [ABSTRACT FROM AUTHOR]

The intricate pollutant composition and pronounced water fluctuations of Chinese liquor brewing wastewater (CLBW) pose formidable challenges for effective treatment, thereby raising significant environmental concerns. This study for the first time delves into the exploration of algal–bacterial granular sludge (ABGS) development and its efficacy in the removal of organic matter and nitrogen and phosphorus over a 100–day investigation of real CLBW treatment. Mature ABGS emerged after approximately 40 days of treating wastewater with 20% real CLBW, exhibiting exceptional settling performance and significant removal of COD (86.2%), NH 4 +–N (98.0%), and TP (51.5%). As the real CLBW proportion increased to 40% or higher, a stable granular structure and excellent settleability persisted, primarily attributed to the consistent content of tightly bound extracellular polymeric substances, the sustained protein–to–polysaccharide ratio, and the proliferation of microalgae within the granules. Microbial community analysis revealed the dominance of microalgal species, including Sphaeropleales , Scenedesmaceae , and Chloromonas. Moreover, the observed decline in nitrification efficiency with increasing CLBW ratio was linked to reductions in Nitrosomonas and Nitrospira populations. Conversely, the recovered TN removal was primarily associated with the accumulation of denitrifiers, including Azoarcus and Thauera , especially when the real CLBW ratio reached 100%. The findings from this study are anticipated to offer a practical reference for optimizing and promoting the treatment of real CLBW. [Display omitted] • Mature ABGS was established within 40 days of treating 20% real CLBW. • Granular structure and settling ability maintained during the extended operation. • Declined COD and N but steady TP removal rates were observed with ≥40% CLBW. • TB-EPS content and PN/PS of ABGS were constant despite the increased CLBW ratio. • Accumulation of denitrifiers in granules contributed to the recovery of TN removal. [ABSTRACT FROM AUTHOR]