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arXiv 2024年

作者： Zhang, Tianyu Hou, Chengbin Jiang, Rui Zhang, Xuegong Zhou, Chenghu Tang, Ke Lv, Hairong The Ministry of Education Key Laboratory of Bioinformatics Bioinformatics Division Beijing National Research Center for Information Science and Technology Department of Automation Tsinghua University Beijing100084 China The School of Computer Science and Engineering Fuyao Institute of Technology Fuzhou350109 China The State Key Laboratory of Resources and Environmental Information Systems Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing100101 China The Department of Computer Science and Engineering Southern University of Science and Technology Shenzhen518055 China The Fuzhou Institute of Data Technology Fuzhou350200 China

Node Importance Estimation (NIE) is a task of inferring importance scores of the nodes in a graph. Due to the availability of richer data and knowledge, recent research interests of NIE have been dedicating to knowledge graphs for predicting future or missing node importance scores. Existing state-of-the-art NIE methods train the model by available labels, and they consider every interested node equally before training. However, the nodes with higher importance often require or receive more attention in real-world scenarios, e.g., people may care more about the movies or webpages with higher importance. To this end, we introduce Label Informed ContrAstive Pretraining (LICAP) to the NIE problem for being better aware of the nodes with high importance scores. Specifically, LICAP is a novel type of contrastive learning framework that aims to fully utilize the continuous labels to generate contrastive samples for pretraining embeddings. Considering the NIE problem, LICAP adopts a novel sampling strategy called top nodes preferred hierarchical sampling to first group all interested nodes into a top bin and a non-top bin based on node importance scores, and then divide the nodes within top bin into several finer bins also based on the scores. The contrastive samples are generated from those bins, and are then used to pretrain node embeddings of knowledge graphs via a newly proposed Predicate-aware Graph Attention Networks (PreGAT), so as to better separate the top nodes from non-top nodes, and distinguish the top nodes within top bin by keeping the relative order among finer bins. Extensive experiments demonstrate that the LICAP pretrained embeddings can further boost the performance of existing NIE methods and achieve the new state-of-the-art performance regarding both regression and ranking metrics. The source code for reproducibility is available at https://***/zhangtia16/LICAP Copyright © 2024, The Authors. All rights reserved.

关键词： Knowledge graph

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Effective Oxidation and Adsorption of As(Iii) in Water by Nanoconfined Ce-Mn Binary Oxides with Excellent Reusability

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SSRN 2024年

作者： Qiu, Shun Chen, Zhanxun Yu, Ling Liu, Chuying Ji, Chenghan Shen, Pengfei Cheng, Sikai Qiu, Hui Fang, Zhuoyao Zhang, Xiaolin Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control School of Environmental Science and Engineering Nanjing University of Information Science & Technology Nanjing210044 China College of Civil Engineering Nanjing Forestry University Nanjing210037 China State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing210023 China

Herein, a highly efficient As(III) purifier Ce-Mn@N201 with excellent reusability was developed by stepwise precipitating hydrated cerium oxides (HCO) and hydrated manganese oxides (HMO) inside N201, a widely-used gel-type anion exchange resin. Owing to confinement of unique nanopores in N201, the in-situ generated nanoparticles (NPs) inside Ce-Mn@N201 were highly dispersed with ultra-small sizes of around 2.6 nm. Results demonstrated that HMO NPs effectively oxidized As(III) to As(V), with most of generated Mn2+ being re-adsorbed onto the negatively-charged surface of HMO NPs. During the regeneration process by simple alkaline treatment, the re-adsorbed Mn2+ was firstly precipitated as (hydr)oxides of Mn(II) and then oxidized to HMO NPs by dissolved oxygen to fully refresh its oxidation capacity. Though HCO NPs mainly served as adsorbent for arsenic, they could partially oxidize As(III) to As(V) at the beginning, while the oxidation capacities continuously diminished with the irreversible conversion of Ce(IV) to Ce(III). In 10 consecutive adsorption-regeneration cycle, Ce-Mn@N201 efficiently decontaminated As(III) from 500 μg/L to below 5 μg/L with Mn2+ leaching less than 0.3% per batch. During 3 cyclic fixed-bed adsorptions, Ce-Mn@N201 steadily produced 8500-9150 bed volume (BV) and 3150-3350 BV drinkable water from the synthesized and real groundwater, respectively, with negligible Mn leaching. © 2024, The Authors. All rights reserved.

关键词： Manganese oxide

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Impacts of Micron-Sized Aeration Bubble on Sludge Properties and Hydraulic Dynamics in Relation to Membrane Fouling Alleviation

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SSRN 2024年

作者： Sun, Huifang Qin, Jiawen Yu, Wei Zhao, Huazhang Wang, Haibo Institute of Resources and Environmental Engineering Shanxi University Taiyuan030006 China College of Environment and Resource Sciences Shanxi University Taiyuan030006 China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China

This investigation elucidates the influence of micron-scale aeration bubbles on the improvement of anti-fouling characteristics within submerged membrane bioreactors (sMBRs). A systematic examination of sludge properties, hydraulic dynamics, and fouling tendencies revealed that the application of microbubble aeration, specifically at dimensions of 100 μm, 80 μm, and 30 μm, significantly reduced sludge electrostatic repulsion and augmented particle size distribution, as opposed to the utilization of coarse bubble aeration of 1mm. Notably, the employment of 100 μm bubbles achieved a significant reduction in the proportion of smaller particles ( © 2024, The Authors. All rights reserved.

关键词： Membrane fouling

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Analyzing surface water quality and assessing environmental impacts downstream of the Tafna river (northwest Algeria)

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Arabian Journal of Geosciences 2024年第6期17卷 1-16页

作者： Mechouet, Ouezna Foudil-Bouras, Ali Eddine Benaissa, Nourredine HADDAD, Fatima Zohra Ait Hamadouche, Yasmine Alexandru, Dimache Geo-Environment Laboratory Faculty of Earth Science Geography and Territorial Planning University of Science and Technology Houari Boumediene (FSTGAT/USTHB) Alger Algeria Environmental Monitoring Networks Research Laboratory (LRSE) Faculty of Nature and Life Sciences University Oran 1 Oran Algeria Biology of Microorganisms and Biotechnology Laboratory (LBMB) Higher School of Biological Sciences of Oran (ESSBO) Oran Algeria Faculty of Hydraulic Works Technical University of Civil Engineering Bucharest Romania

The Tafna river serves as a model for assessing surface water and environmental quality by combining water quality and pollution indices using multivariate statistical methods. Thirty-six surface water samples were analyzed to assess 13 indicators. The results indicate contamination of the surface waters of the Tafna river by organic matter and the influence of lithology (presence of calcite), leading to an enrichment in Cl−, SO42−, and Ca2+ by dissolution (9.6–4.8 and 4.06 mg.l−1, respectively). During the summer and autumn, pH, electrical conductivity (EC), biochemical oxygen demand (BOD) reaching 57 mg.l−1, chemical oxygen demand (COD) at 90.9 mg.l−1, N-NH4+, and N-NO3− showed significant increases. In addition, the pollution index revealed the absence of pollution during winter and early summer but moderate levels of pollution in autumn. In addition, the spatial distribution of the water quality index (WQI) indicates good water quality in the estuary upstream to 54.94, but progressive deterioration upstream. However, analysis of the correlation matrix highlighted the influence of various sources, both natural and human, on surface water quality. In particular, a significant correlation (R2 = 0.9) was observed between Ca2+ and HCO3− concentrations, indicating a close relationship between these two elements. Organic pollution of the waters of the Tafna river has been strongly influenced by wastewater discharge and agricultural activities, which could lead to potential health risks if consumed. The results of this study provide a sound scientific basis to support decision-making and the implementation of measures to preserve and sustainably manage the Tafna river.

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Porphyrins Functionalized Covalent Organic Frameworks for Enhanced Photodynamic and Photothermal Antibacterial

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SSRN 2024年

作者： Cheng, Zi Jian Xu, Han Bin Chen, Hua Ying Li, Dan Gao, Ya Ting Xi, Cheng Ye Ye, Ming Jie He, Yue Li, Da Wei Chen, Bin Bin Key Laboratory for Advanced Materials Shanghai Key Laboratory of Functional Materials Chemistry Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology & Dynamic Chemistry School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai200237 China College of Biology and Environmental Engineering Zhejiang Shuren University Hangzhou310015 China

Porphyrins, as important organic photosensitizers, have attracted widespread attention in photodynamic and photothermal therapy. However, the poor water solubility of porphyrins causes their tendency to aggregate in living organisms, resulting in unsatisfactory photodynamic and photothermal effects. In this work, we have ingeniously designed a kind of photoactive COFs-Tph by covalent coupling hydrophobic porphyrin (Tph) on the surface of porous covalent organic frameworks (COFs) with free aldehyde groups. Under 660 nm light irradiation, the proposed COFs-Tph exhibit high 1O2 generation ability and photothermal conversion efficiency (50.56%) simultaneously. Importantly, the COFs-Tph display the obviously enhanced photodynamic and photothermal performance compared to Tph, which is attributed not only to the high loading capacity of COFs on Tph, but also to covalent coupling between COFs and Tph that improves the dispersibility of Tph. Because of the excellent phototherapeutic ability, the COFs-Tph are used as the antibacterial nanoreagents to kill 100% both Gram-negative and Gram-positive bacteria in just 5 min. This work develops a powerful strategy to construct phototherapeutic nanoreagents with enhanced photodynamic and photothermal properties and achieve efficient antibacterial purposes. © 2024, The Authors. All rights reserved.

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Double transition metal atoms anchored on Graphdiyne as promising catalyst for electrochemical nitrogen reduction reaction

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Journal of Materials science & technology 2021年第18期77卷 244-251页

作者： Lakshitha Jasin Arachchige Yongjun Xu Zhongxu Dai Xiao Li Zhang Feng Wang Chenghua Sun School of Chemical Engineering and Energy Technology Dongguan University of TechnologyDongguan 523808China Department of Chemistry and Biotechnology and Centre for Translational Atomaterials.FSETSwinburne University of TechnologyHawthornVictoria 3122Australia Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials.College of Materials and Chemical Engineering China Three Gorges UniversityYichang 443002China State Centre for International Cooperation on Designer Low-Carbon&Environmental Materials.School of Materials Science and Engineering Zhengzhou UniversityHenan 450001China

Ammonia synthesis by electrochemical nitrogen reduction technique is an attractive alternative to traditional Haber-Bosch ***,development of an efficient and effective electrocatalyst is one of the remaining key *** this work,density functional theory(DFT)computations were systematically employed on double transition metal atoms(Fe,Co,Ni,Cu and Mo)anchored Graphdiyne(GDY)for nitrogen reduction reaction(NRR).The Co-Ni heteronuclear complex and Mo-Mo homonuclear complex showed the highest NRR activity while demonstrating synergistic effect of double atomic catalytic sites towards the promising NRR activity.

关键词： Double atom catalyst Graphdiyne NRR First-principles calculation

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The Impact of Dissolved Organic Nitrogen (Don) Retention in the Vadose Zone on Nitrogen Leaching Losses

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SSRN 2024年

作者： Hao, Yujie Zheng, Tianyuan Zheng, Xilai Liu, Lechen Jiang, Shiqiang Cao, Min Luo, Jian College of Environmental Science and Engineering Ocean University of China Qingdao266100 China Key Laboratory of Marine Environment and Ecological Education Ocean University of China Qingdao266100 China Qingdao Hydrological Center Shandong Qingdao266101 China School of Civil and Environmental Engineering Georgia Institute of Technology AtlantaGA30332 United States

Leaching of dissolved organic nitrogen (DON) is a significant pathway for nitrogen (N) loss in agricultural ecosystems. The excessive application of nitrogen for enhanced agricultural productivity often results in the leaching of N into groundwater. Yet not well understood, the extent of retention in the vadose zone has critical implications for risk management and remediation strategies. This study aims to advance simulation techniques for modelling the transport process of reactive DON within a heterogeneous vadose zone. Through a combination of laboratory experiments and numerical simulations, the study firstly examines the extent of DON retention in the vadose zone and quantitatively analyse groundwater contamination risk from this kind of accumulation. Our findings indicate that heavy nitrogen fertilizer application and high-intensity rainfall events lead to elevated concentrations of DON in the vadose zone and increased DON leaching fluxes into groundwater. In our scenarios, DON accounted for a substantial portion (33–68%) of the total dissolved nitrogen (TDN) leaching fluxes, with exogenous DON content contributing significantly (25–85%) to the overall DON leaching into the aquifer. These results underscore the need for effective strategies to mitigate groundwater contamination risks associated with agricultural nitrogen use. © 2024, The Authors. All rights reserved.

关键词： Aquifers

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Evolutions of Functional Groups and Polycyclic Aromatic Hydrocarbons (PAHs) During Low Temperature Pyrolysis of a Perhydrous Bituminous Coal

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SSRN 2023年

作者： Cai, Jiawei Wang, Ruwei Huang, Qing Huang, Zhuliang Xu, Yuchan Liu, Zhixiang Yang, Qiling Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health Guangzhou China School of Environmental Science and Engineering Institute of Environmental Health and Pollution Control Guangdong University of Technology Guangzhou510006 China Guangdong Key Laboratory of Environmental Pollution and Health School of Environment Jinan University Guangzhou511443 China

This study investigated changes in functional groups and extractable polycyclic aromatic hydrocarbons (PAHs) in a perhydrous bituminous coal and its pyrolyzed products. Kinetic estimation and molecular structure modeling were performed to reveal the pyrolysis mechanism. Results indicated that evolutions of aliphatic, aromatic C–H and C=C, and C-, O-, N-, and S-species declined in relative contents during pyrolysis of coal, and they had different declining rates in low- ( © 2023, The Authors. All rights reserved.

关键词： Molecular structure

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Flotation Separation Mechanism of Rutile and Chlorite Using Cmc as Depressant

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SSRN 2024年

作者： Gong, Peng Ren, Liuyi Bao, Shenxu Zhang, Yimin Qin, Wenqing Nguyen, Anh V. School of Resources and Environmental Engineering Wuhan University of Technology Wuhan430070 China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and Technology Wuhan430081 China School of Minerals Processing and Bioengineering Central South University Changsha410083 China School of Chemical Engineering The University of Queensland BrisbaneQLD4072 Australia

In ores containing rutile, chlorite is the most characteristic silicate gangue mineral. However, the flotation separation of rutile and chlorite has yet to be thoroughly studied. In this study, carboxymethyl cellulose (CMC) was used to depress chlorite when sodium oleate (NaOL) was used as the collector of rutile. The selective depression and its mechanism were investigated through micro-flotation experiments, zeta potential analyses, Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and particle video microscopy (PVM). Single mineral flotation showed selective depression of chlorite by CMC appeared at pH 7, NaOL concentration of 20 mg/L, and CMC concentration of 10 mg/L, when 88.39% recovery difference between rutile and chlorite was obtained. The most effective concentration of CMC for the artificially mixed ore test was 15 mg/L, resulting in rutile recoveries and grades of 87.78% and 75.28% respectively. The results of Zeta, FTIR, and XPS tests indicate that the adsorption of CMC on chlorite surface is attributed to chemical and hydrogen bonding interactions, wherein the OH- and COOH- groups in CMC interact with hydroxyl groups of Fe2+ and Al3+ complexes, thereby diminishing chlorite floatability and impeding subsequent NaOL adsorption. PVM imagery further elucidates that hydration-repulsion interaction potentials between CMC-absorbed chlorite particles and gas bubbles deter particle adhesion. This markedly reduces chlorite ore carryover on bubble surfaces while minimally impacting rutile. This study can provide a theoretical basis for separating rutile and other vein minerals under the NaOL system and provide a reference for the problem of sorting difficulties of primary rutile. © 2024, The Authors. All rights reserved.

关键词： Flotation

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hcp-phased Ni nanoparticles with generic catalytic hydrogenation activities toward different functional groups

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science China Materials 2022年第5期65卷 1252-1261页

作者： Yang Lv Xin Mao Wanbing Gong Dongdong Wang Chun Chen Porun Liu Yue Lin Guozhong Wang Haimin Zhang Aijun Du Huijun Zhao Key Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyInstitute of Solid State PhysicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Chemistry Physics and Mechanical EngineeringScience and Engineering FacultyQueensland University of TechnologyGardens Point CampusBrisbaneQLD 4001Australia Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Centre for Catalysis and Clean Energy Griffith UniversityGold Coast CampusQueensland 4222Australia

Catalytic hydrogenation is a vital industrial means to produce value-added fuels and fine chemicals,however, requiring highly efficient catalysts, especially the nonprecious ones. To date, the majority of high-performance industrial hydrogenation catalysts are made of precious metals-based materials, and any given catalyst could only be used to catalyze one or few specific reactions. Herein, we exemplify a crystal phase engineering approach to empower Ni nanoparticles(NPs) with superb intrinsic catalytic activities toward a wide spectrum of hydrogenation reactions. A facile pyrolysis approach is used to directly convert a Ni-imidazole MOF precursor into hexagonal close-packed(hcp)-phased Ni NPs on carbon support. The as-synthesized hcp-phased Ni NPs exhibit unprecedented hydrogenation catalytic activities in pure water towards nitro-, aldehyde-, ketone-, alkene-and N heterocyclic-compounds, outperforming the face-centered cubic(fcc)-Ni counterpart and the reported transition metalsbased catalysts. The density functional theory calculations unveil that the presence of hcp-Ni boosts the intrinsic catalytic hydrogenation activity by coherently enhancing the substrate adsorption strength and lowering the reaction barrier energy of the rate-determining step. We anticipate that the crystal phase engineering design approach unveiled in this work would be adoptable to other types of reactions.

关键词： crystal phase engineering hcp-phased Ni nanoparticles catalytic hydrogenation DFT calculations H_(2)O solvent

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