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Cation defect engineering in LaCoO3 perovskite as the "Two birds one stone" strategy to enhanced Fenton-like reaction: Regulating Co spin state and optimizing electron transfer ability

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SEPARATION AND PURIFICATION TECHNOLOGY 2024年 337卷

作者： Fang, Zhimo feng, xuwen Zhou, Zhou Zeng, Zepeng Xia, Yuangu Li, Jihong Liu, Ji Hu, Bin Li, Kai Lu, Qiang North China Elect Power Univ Natl Engn Res Ctr New Energy Power Generat Beijing 102206 Peoples R China

The reactive oxygen species (ROS) triggered by peroxymonosulfate (PMS), primarily composed of radicals and nonradicals, can deeply and selectively remove pollutants in complex wastewater. However, the low efficiency of electron transfer and insufficient surface catalytic sites remain the main obstacles to the development of efficient and selective PMS activators. Herein, we constructed ABO(3) perovskite catalysts (LaCoO3) with adjustable La vacancies (V-La) densities through urea introduction. Experiment, characterization, and theoretical calculation jointly revealed that VLa could not only induce electron delocalization in Co site to enhance the Co 3d - O 2p covalency for accelerating ROS (sulfate radicals (SO4 center dot-), singlet oxygen (O-1(2)), and high valent cobalt (Co(IV) = O)) generation, but also trigger the transition of spin-polarization configuration to form Co3+ (t(2g)(5)e(g)(1)) with the intermediate spin state as new active sites for surface-bound PMS* complexes production. The nonradical-dominated and radical-assisted system containing multi-site achieved efficient PMS utilization (95.6 %), excellent decontamination activity (0.753 min(-1)), good mineralization ability (82.7 %), satisfactory acid-base resistance (working pH range 3-11), and environmental robustness for actual water treatment. This study reveals the role of cation vacancy engineering in achieving "Two birds one stone" for PMS activation at the atomic level, which will guide the rational design of Fenton-like catalysts.

关键词： Peroxymonosulfate La vacancies Spin state Delocalization Radicals and nonradicals

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海洋气象观测标准国际化路径:以船舶气象仪为例

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海洋学研究 2023年第2期41卷 123-130页

作者：马乐天郭晓维漆随平冯旭文花卫东自然资源部第二海洋研究所浙江杭州310012 自然资源部海底科学重点实验室浙江杭州310012 中国仪器仪表学会北京100088 齐鲁工业大学(山东省科学院) 山东青岛266001 山东省科学院海洋仪器仪表研究所山东青岛266001 航天新气象科技有限公司江苏无锡214127

船舶气象仪是海洋水文气象观测技术的重要组成部分,其发展对实现全球海洋同步观测至关重要,而主导制定基于共识的相关国际标准,将有力推动我国船舶气象仪制造业的市场规范化和产品国际化。该文从船舶气象仪的重要性入手,分析了国内外船... 详细信息

船舶气象仪是海洋水文气象观测技术的重要组成部分,其发展对实现全球海洋同步观测至关重要,而主导制定基于共识的相关国际标准,将有力推动我国船舶气象仪制造业的市场规范化和产品国际化。该文从船舶气象仪的重要性入手,分析了国内外船舶气象仪标准的发展历程,概述了相关标准化组织的工作现状,重点阐述了如何从优化关键技术指标和借助海洋技术国际标准化平台这两个方面,来推进船舶气象仪国际标准化工作。

关键词：船舶气象仪 ISO国际标准海洋水文气象观测

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海洋技术国际标准化工作的现状及其发展趋势

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中国造船 2021年第3期62卷 258-266页

作者：马乐天王瑶姜磊冯旭文叶聪李家彪自然资源部第二海洋研究所杭州310012 自然资源部海底科学重点实验室杭州310012 中国船舶科学研究中心无锡214082 深海载人装备国家重点实验室无锡214082

海洋技术的发展需要实现跨领域的学科交叉,而基于共识的国际标准将为这一新兴技术的全球推广提供必要支撑。论文从海洋技术的背景入手,概述了当今海洋技术领域国际标准化组织的工作现状,对现行的和制订中的相关国际标准进行了梳理,重点... 详细信息

海洋技术的发展需要实现跨领域的学科交叉,而基于共识的国际标准将为这一新兴技术的全球推广提供必要支撑。论文从海洋技术的背景入手,概述了当今海洋技术领域国际标准化组织的工作现状,对现行的和制订中的相关国际标准进行了梳理,重点阐述了潜水器国际标准的起步与实践。对我国在海洋技术国际标准化工作中所做的贡献予以初步总结,分析了工作前景和发展趋势,并提出了未来工作重点。

关键词：海洋技术潜水器 ISO国际标准

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Dynamic performance of an integrated heat pump system coupled free cooling and waste heat recovery in data centers

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ENERGY 2025年 323卷

作者： Zhou, feng Tian, xuwen Song, Yu Ma, Guoyuan Beijing Univ Technol Dept Refrigerat & Cryogen Engn Beijing 100124 Peoples R China Key Lab Heat Transfer & Energy Convers Beijing Peoples R China

Recovering and reusing this waste heat for district heating is an effective strategy to enhance energy efficiency in data centers. To align data center waste heat recovery with heat consumer demand and improve energy utilization, a transient mathematical model of a data center-integrated heat pump district heating system was developed and validated. A case study involving a small data center with 300 standard racks in Beijing was conducted to analyze the system's operational and dynamic behavior. The results show that hot water and heating account for 35.70 % and 64.30 % of the total heat consumption, respectively. During the heating season, the heating heat pump unit exhibits a high heating coefficient of performance (COP), with a maximum heating COP of 5.27. Under year-round operation, the COP of the hot water heat pump unit exhibited periodic 24-h variations. Peak water consumption occurred from 6:00 to 9:00 and 21:00 to 24:00, with corresponding heating COP values of 3.87 and 4.24, respectively. The proposed system in addressing the cooling demand of the data center and the heating and hot water demands of the heat consumers, providing a feasible solution for improving the energy utilization efficiency of data centers.

关键词： Data center Waste heat recovery Dynamic performance analysis Integrated heat pump district heating system

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The synthesis of an iron tailings-based geopolymer with synergistic electromagnetic wave consumption property

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ENVIRONMENTAL RESEARCH 2025年 268卷 120744页

作者： Wang, Tianyu Ning, xuwen Yang, Lang Rao, feng Jiang, Kaixi Fuzhou Univ Sch Mat Sci & Engn Fuzhou 350108 Fujian Peoples R China Fuzhou Univ Zijin Sch Geol & Min Fuzhou 350108 Fujian Peoples R China Fuzhou Univ Fujian Key Lab Green Extract & High Value Utilizat Fuzhou 350108 Fujian Peoples R China

In this study, combination of wave absorption materials with different loss mechanisms are added into iron ore tailings-blast furnace slag (IOT-BFS) based geopolymers. The employed materials are hollow glass microsphere (HGM), carbon nanotubes (CNT) and carbonyl iron powder (CIP). Microstructures of the geopolymers are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and concrete porous structure analyzer. Conductivity and electromagnetic absorption property of the geopolymers are measured by a conductivity tester and a vector network analyzer (VNA). As increasing the content of wave absorption materials, compressive strength of the geopolymer decreased from 60.5 to 33.8 MPa. Compared with geopolymers containing HGM and CNT, wave absorption band below -5 dB of the geopolymers with HGM and CIP was wider, particularly at frequencies below 7 GHz, due to the synergism of space and magnetic loss. Its absorption bandwidth with the reflection loss less than -5 dB reaches 15.6 GHz. This study gives a clue for preparation of geopolymers with satisfactory electromagnetic wave absorption properties in the utilization as construction materials.

关键词： Geopolymers Electromagnetic wave absorption Iron ore tailings Microstructure

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Ladderane records over the last century in the East China sea: Proxies for anammox and eutrophication changes

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WATER RESEARCH 2019年第Jun.1期156卷 297-304页

作者： Zhao, Zongshan Cao, Yali Fan, Ying Yang, Haili feng, xuwen Li, Li Zhang, Hailong Xing, Lei Zhao, Meixun Ocean Univ China Inst Adv Ocean Study Minist Educ Key Lab Marine Chem Theory & Technol Qingdao 266100 Shandong Peoples R China Qingdao Natl Lab Marine Sci & Technol Lab Marine Ecol & Environm Sci Qingdao 266237 Shandong Peoples R China Chinese Acad Sci Qingdao Inst Bioenergy & Bioproc Technol CAS Key Lab Biobased Mat Qingdao 266101 Shandong Peoples R China Jiangxi Inst Anal & Test Nanchang 330029 Jiangxi Peoples R China State Ocean Adm Inst Oceanog 2 Hangzhou 310012 Zhejiang Peoples R China

Anaerobic ammonium oxidation (anammox), an important process for converting fixed nitrogen to N-2, plays an important role in the present-day marine nitrogen cycle. However, little is known about anammox activities in the past, especially in regions that were strongly affected by human activities, evidenced by eutrophication and hypoxia, which promote anammox bacteria growth. In this study, ladderanes have been measured in a sediment core and suspended particulate matter (SPM) in the East China Sea (ECS), to reconstruct the anammox record and to evaluate its responses to eutrophication and hypoxia. The detection and distribution of different ladderane lipids in SPM provide additional evidence that ladderanes were mostly produced in the water column and could reflect anammox activities. Summed ladderane content from the core varied between 11 and 300 ng/g dry weight (dw) sediment, with C20-[5]-ladderane fatty acid methyl esters (FAME) as the predominant compound (5-150 ng/g dw), followed by C20-[3]-ladderane FAME (1-110 ng/g dw), C18-[3]-ladderane FAME (1-32 ng/g dw) and 08 -[5]-ladderane FAME (3-11 ng/g dw). The detection of ladderanes over the last century indicate the existence of anammox in the past. The rapidly increasing trend of ladderanes since the 1960s correlates with an increase in phytoplankton biomarkers (2 Sigma(B + D + A), brassicasterol (B), dinosterol (D) and C-37 alkenones (A)), indicating that eutrophication exacerbated anammox growth. The co-variation between our ladderane record and published records of low-oxygen tolerant foraminiferal microfossils and hypoxia events over the past 60 years suggested that sediment ladderanes are a useful indicator for past changes of oxygen depletion or hypoxia in the ECS. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Anammox Ladderanes Nitrogen cycle Phytoplankton Hypoxia

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Phytoplankton community changes in a coastal upwelling system during the last century

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Global and Planetary Change 2023年 224卷

作者： Peng, Peng Bi, Rong Sachs, Julian P. Shi, Jie Luo, Yifei Chen, Weifang Huh, Chih-An Yu, Meng Cao, Yali Wang, Yaoyao Cao, Zhong Bao, Xiaohan Guo, Xinyu Li, Huijuan feng, xuwen Li, Hongchun Zhao, Meixun Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao266100 China Laoshan Laboratory Qingdao266237 China School of Oceanography University of Washington Box 355351 SeattleWA98195 United States Key laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao266100 China State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences Xiamen University Xiamen361102 China Institute of Earth Sciences Academia Sinica Taipei11529 Taiwan Yantai Maritime Safety Administration Yantai264000 China Jinan250014 China Second Institute of Oceanography Ministry of Natural Resources of People's Republic of China Hangzhou310012 China Department of Geosciences National Taiwan University Taipei10617 Taiwan

Phytoplankton communities in coastal upwelling systems are influenced by the interplay between human-induced and natural climate forcing that vary regionally and the two factors have not been well quantified. Combining lipid biomarker analyses in 23 sediment cores from the Zhejiang coast of the East China Sea and a physical-ecological model, we found that during the 1960s–2000s there was a 42 ± 4% increase in diatom proportions and a 17 ± 8% decrease in dinoflagellate proportions within the core upwelling area that is attributed to changes in Kuroshio Current transport and coastal upwelling. During the 1950s–2000s there was a 16 ± 8% increase in dinoflagellate proportions and 12 ± 4% decrease in diatom proportions outside the core upwelling area which is attributed to anthropogenic nutrient inputs and climate warming. Our results provide a novel approach to quantify mechanisms of past and future changes in marine phytoplankton communities. © 2023 Elsevier B.V.

关键词： Ocean currents

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A novel electromagnetic wave absorption geopolymer originated from iron tailings and blast furnace slag

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MATERIALS AND STRUCTURES 2025年第1期58卷 1-14页

作者： Ning, xuwen Yang, Lang Rao, feng Wang, Tianyu Wu, Shengping Huang, Hanhui Fuzhou Univ Zijin Sch Geol & Min Fuzhou 350108 Fujian Peoples R China Zhiyong Construct Grp Co Ltd Fuzhou 350800 Fujian Peoples R China Fuzhou Univ Fujian Key Lab Green Extract & High Value Utilizat Fuzhou 350108 Fujian Peoples R China State Key Lab Mineral Proc Beijing 102628 Peoples R China Fujian JiangXia Univ Sch Engn Fuzhou 350108 Fujian Peoples R China Zhongke Chengfa Fujian Construct Grp Co Ltd Nanping 354105 Fujian Peoples R China Coll Civil Engn Fujian ChuanZheng Commun Coll Fuzhou 350007 Fujian Peoples R China

In this work, a novel electromagnetic wave absorption geopolymer was created with efficient utilization of two solid wastes iron tailings and blast furnace slag, meanwhile the mechanism and impacts of iron tailings content, water-solid ratio and specimen thickness on their electromagnetic wave absorption and mechanical property were systematically investigated. It was found the pores, micro-cracks and unreacted particles in the specimens are benefitial for electromagnetic wave absorption but against to compressive strength, even though the compressive strength reaches 69.7 MPa with the iron tailings content 50% and water-solid ratio 0.4. The addition of iron tailings significantly enhances the electromagnetic wave absorption properties of the geopolymers, and increasing iron tailings content improves the number of pores, micro-cracks and the permeability of geopolymers. The electromagnetic wave absorption properties of the geopolymer initially increase and then decrease with the increase of specimen thickness and water-solid ratio. With an iron tailings content 70%, water-solid ratio 0.4 and thickness 30 mm, the effective absorption bandwidth (< -5 dB) was optimized to 10.44 GHz with a minimum reflection loss of -13.34 dB. A new mechanism for electromagnetic absorption in iron tailings has been proposed, in which the electromagnetic wave absorption of geopolymers is mainly dominated by magnetic loss and spatial propagation loss. This study provides higher competitiveness and comprehensive utilisation of iron tailings in the field of electromagnetic wave absorbing building materials, and has great potential for applications in military and other fields affected by high electromagnetic wave frequencies.

关键词： Iron tailings Geopolymers Microwave absorption Reflectivity

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Beyond transcription, aryl hydrocarbon receptor plays a protective role in periodontitis by interacting with CaMKII

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JOURNAL OF PERIODONTOLOGY 2025年第1期96卷 67-81页

作者： Zeng, xuwen feng, Meiting Lu, Jiawei Wang, Ruiling Deng, Li Yang, Yanan Luo, Lijun Tongji Univ Stomatol Hosp Shanghai Engn Res Ctr Tooth Restorat & Regenerat Dept Periodontol Shanghai Peoples R China Tongji Univ Shanghai Engn Res Ctr Tooth Restorat & Regenerat Dent Sch Shanghai Peoples R China Univ Porto Inst Res & Innovat Hlth i3S Inst Invest & Inovacao Saude Porto Portugal Univ Porto Inst Mol & Cell Biol IBMC Inst Biol Mol & Celular Porto Portugal

Background: The aryl hydrocarbon receptor (AhR) has been studied as an intracellular pattern recognition receptor that can identify bacterial pigments. To identify a potential therapeutic target for periodontitis, we investigated the expression of AhR in periodontitis and its role in the pathogenesis of periodontitis. Methods: First, we analyzed AhR expression in a single-cell dataset from human periodontal tissue. Quantitative polymerase chain reaction (qPCR), immunofluorescence, and immunohistochemistry were used to verify the AhR level. Later, we determined the phenotypes of ligature-induced periodontitis in myeloid-specific AhR-deficient mice (Lyz2-Cre(+/-) AhR(fx/fx)), after which RNA sequencing (RNA-seq), qPCR, Western blot, immunofluorescence, and immunohistochemistry were used to investigate the impacts of AhR on periodontitis and its mechanism. Finally, we determined the therapeutic effect of AhR agonist 6-Formylindolo[3,2-b]carbazole (FICZ) administration on murine periodontitis and verified the effects of FICZ on macrophage polarization in vitro. Results: AhR expression was enhanced in macrophages from periodontitis patients. Deletion of AhR from macrophages aggravated ligature-induced periodontitis and promoted the inflammatory response. Calcium/calmodulin-stimulated protein kinase II (CaMKII) phosphorylation was accelerated in AhR-deficient macrophages. Inhibiting CaMKII phosphorylation ameliorated periodontitis in Lyz2-Cre(+/-) AhR(fx/fx) mice. FICZ treatment blocked alveolar bone loss and relieved periodontal inflammation. FICZ diminished M1 macrophage polarization and promoted M2 macrophage polarization upon M1 macrophage induction. Conclusion: AhR played a protective role in the pathogenesis of periodontitis by orchestrating macrophage polarization via interacting with the CaMKII signaling pathway.

关键词： aryl hydrocarbon receptor CaMKII macrophage pattern recognition receptor periodontitis

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Pioneering Insights into the Reaction Kinetics of Metastable Intermolecular Composites Based on Metal Fluorides: Virtually non-existent condensed Phase Combustion Products and Ultra-Efficient Reactivity

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ADVANCED SCIENCE 2025年第14期12卷 e2415073页

作者： Liu, xuwen Li, Jingwei feng, Shenghua Jia, Yongsheng Hu, Maocong Yao, Yingkang Sun, Jinshan Xie, Quanmin Sang, Hongqian Jianghan Univ State Key Lab Precis Blasting Wuhan 430113 Peoples R China Jianghan Univ Hubei Key Lab Blasting Engn Wuhan 430056 Peoples R China Anhui Univ Sci & Technol Sch Chem & Blasting Engn Huainan 232001 Peoples R China Jianghan Univ Sch Optoelect Mat & Technol Wuhan 430056 Peoples R China

As a typical representative of Metastable intermolecular composites (MICs), the energy release of nano-thermites relying on aluminum-oxygen reaction is limited by the formation of high boiling point condensed phase products. Low pressure output performance constitutes another pivotal factor influencing their efficacy. In this work, metal fluorides BiF3 at different scales were incorporated into nano-thermites as oxidants, thereby facilitating the tunability of the released energy. The boiling points of all resultant reaction products fall below the combustion temperature, theoretically abolishing the agglomeration of condensed-phase products, thus preventing the entrapment of active metals. Additionally, it facilitates the smooth conduction of heat flux, thereby averting losses in biphasic flow dynamics. The n-Al/n-BiF3 system exhibits a significant amplification in reactive kinetic properties in stark contrast to the n-Al/n-Bi2O3 system. The reduction in ignition threshold is ascribed to a novel reaction kinetics mechanism within the n-Al/BiF3 system. The highly electronegative fluorine within BiF3 corrodes the Al2O3 shell, inducing a "pre-ignition" reaction. The application of Density Functional Theory (DFT) evaluations has further corroborated the n-Al/n-BiF3 system's preeminence in electron transfer capacity between the oxidizing agent and fuel, thereby furnishing an molecular-electronic basis for its potent reactive kinetic properties.

关键词： combustion mechanism metal fluorides metastable intermolecular composites nanostructured energetic materials pre-ignition reactions

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