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Hypoxia in the Changjiang Estuary over the last 100 years

Hypoxia in the Changjiang Estuary over the last 100 years

The 17th International Conference on Heavy Metals in the Environment (ICHMET2014)(第十七届国际环境重金属会议)

作者： Weiyan Zhang Xuefa Shi Hongliang Li xuwen feng Key Laboratory of Marine Sedimentology and Environment al Geology First Institute of OceanographySOAQingdaoChina Laboratory of Marineecosystem and BiogeochemistrySOAHangzhouChina Laboratory of Submarine GeosciencesSOAHangzhouChina Second Institute of OceanographyState Oceanic Administration(SOA)HangzhouChina

Two cores were selected in the Changjiang Estuary and its adjacency,one within the region of seasonal hypoxia and the other nearby but outside the hypoxia *** major elements,trace elements and rare earth elements(REEs)were determined on the 210Pb-dated sediment *** distributions of most elements in the core sediment outside the hypoxia region were controlled by “grain size effects”.In the core sediment within the hypoxia region,some redox sensitive elements(RSEs)just like the Mo,Cd,As et *** been enriched significantly,which concentrations increased about 83%,73%and 50%respectively since the late 1960s to *** the Mn has been depleted since *** results indicate the redox environment of the bottom water-sediment interface has been changed which might be caused by the eutrophication and hypoxia in the Changjiang *** concentrations of biogenic elements as well as Ca,Sr,P have also increased about 129%,65%and 38%respectively since the late 1960s,which reflected the increasing of productivity and biomass influenced by the anthropogenic activities during the last forty *** results showed that the contents of biogenic elements as well as Ca,Sr,P and some RSEs just like Mo,Cd,As,Mn in sediment could be used to trace or reconstruct history of the coastal eutrophication and hypoxia in the high productivity zone in the Changjiang Estuary over the last 100 *** were correlated negatively with Ti,Al,Fe and no obvious relation with grain *** decreasing trend of δCe distribution over the last 100 years may be related to the progressive hypoxia and high productivity in the Changjiang *** geochemical parameters gave the same conclusions consistently: effected by the anthropogenic activity,the Changjiang estuary hypoxia began in 1970s and showed the increasing trend.

关键词： redox sensitive elements (RSEs) biogenic elements rare earth elements (REEs) sediment core Changjiang Estuary

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海洋技术国际标准化在中国的起步及其实践意义

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地球科学进展 2017年第6期32卷 660-667页

作者：马乐天冯旭文李家彪国家海洋局第二海洋研究所浙江杭州310012 国家海洋局海底科学重点实验室浙江杭州310012

通过探讨海洋技术国际标准未来发展的4个方向:(1)海洋观测国际标准与先进的制造技术、信息技术相结合;(2)海洋通用技术朝着标准化方向发展;(3)海洋资源勘探与国际标准的紧密联系;(4)向更深的深海发展——潜水器技术与国际标准相结合,总... 详细信息

通过探讨海洋技术国际标准未来发展的4个方向:(1)海洋观测国际标准与先进的制造技术、信息技术相结合;(2)海洋通用技术朝着标准化方向发展;(3)海洋资源勘探与国际标准的紧密联系;(4)向更深的深海发展——潜水器技术与国际标准相结合,总结了我国现阶段在海洋技术国际标准化领域的初步实践成果。同时指出国际标准化组织海洋技术分委会(ISO/TC8/SC13)落户中国,是带动我国海洋技术标准走出去的契机,有利于推进海洋科技研发、标准研制和产业发展一体化。

关键词：海洋技术海洋观测海洋资源勘探国际标准

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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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Finite element analysis of corn kernel damage: a viscoelastic model approach for impact-induced damage prediction

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JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2025年第7期105卷 3993-4004页

作者： Zhao, Xuelin Zhang, Qiang Fang, xuwen Zhang, Jinsong feng, Weijing Zhang, Li Zhou, Deyi Yu, Chunsheng Wang, Hao Gao, Xiaodi Zhou, Haigen Wu, Xinling Jilin Univ Coll Biol & Agr Engn Changchun 130022 Peoples R China

BACKGROUNDIn the present study, we address the quality degradation of corn during post-harvest processing by developing a viscoelastic composite model to predict kernel damage during post-harvest processing. The model, based on high-resolution scanning and inverse modeling techniques, provides an accurate representation of the complex internal components of corn kernels, which allows for the analysis of their stress response and damage susceptibility trends under different impact *** results show that the viscoelastic model has a relative error of 2.4% compared to the drop test data, thus demonstrating that the viscoelastic model has a very high accuracy in predicting impact damage and is able to accurately localize the flour-like endosperm as the main region of impact damage. The model showed a high correlation (0.99) between predicted and experimental damage rates by response surface *** damage during processing is reduced by reducing the proportion of flour-like endosperm in maize kernels. A new method for reducing damage during food handling and processing operations is proposed, providing an important reference for improving kernel durability and contributing to the development of gentler processing techniques to improve the quality of maize products. (c) 2025 Society of Chemical Industry.

关键词： viscoelastic composite model collision damage finite element method burgers model high moisture corn kernel

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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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国际背景下的海洋调查技术标准化发展路径研究

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海洋学研究 2020年第1期38卷 87-94页

作者：马乐天冯旭文吕小飞吴春芳李家彪自然资源部海底科学重点实验室浙江杭州310012 自然资源部第二海洋研究所浙江杭州310012

通过对比分析我国与美国、欧盟的标准战略、标准化组织机构、标准体系和海洋调查技术标准具体的制订现状,综合比较了我国与发达国家之间的差异,建议借鉴以民间自由竞争为特点的美国标准模式和以高度国际化的标准体系为特点的欧洲标准模... 详细信息

通过对比分析我国与美国、欧盟的标准战略、标准化组织机构、标准体系和海洋调查技术标准具体的制订现状,综合比较了我国与发达国家之间的差异,建议借鉴以民间自由竞争为特点的美国标准模式和以高度国际化的标准体系为特点的欧洲标准模式,同时充分发挥国际标准化组织海洋技术分委会(ISO/TC8/SC13)主席和秘书处落户中国这一平台优势的桥梁作用,探索我国海洋调查技术标准国际化的有效路径。

关键词：海洋调查技术标准国际标准化组织

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Tribological application and mechanism of epicuticular wax

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Friction 2019年第1期7卷 44-58页

作者： xuwen ZHONG Yanqiu XIA Xin feng School of Energy Power and Mechanical Engineering North China Electric Power University

The plant cuticle is a complex mixture of omnipresent, commonly monofunctional, fatty acid derivatives and taxon-specific, generally bifunctional, specialty compounds. This study explored expanded applications for these substances. Four types of plant cuticles were distilled from leaves and the resulting lipid mixtures were analyzed using gas chromatography-mass spectrometry. These were then used as additives for a synthetic ester lubricant. A reciprocating friction and wear testing machine was utilized to investigate the resulting tribological properties. The worn surfaces of the lower discs were observed and analyzed using optical microscopy and time-of-flight secondary ion mass spectrometry. The results reveal that cuticular waxes can modify the friction properties of the base oil. Furthermore, cuticular waxes demonstrate better performance when compared to the commercially available additive molybdenum dithiocarbamates. A protective adsorption film was identified as the reason for the improved friction reduction and anti-wear properties of the lubricant on the friction pair. This study provides a reference for the study of new types of non-sulfur, phosphorus, and other active element additives and demonstrates considerable potential for the economical utilization of plant leaf waxes.

关键词： epicuticular wax tribological application GC-MS TOF-SIMS adsorption

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浙江近岸泥质区百年来浮游植物生产力的变化及对环境的响应

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海洋学报 2013年第4期35卷 155-161页

作者：冯旭文段杉杉石学法刘升发赵美训杨海丽朱德弟王奎国家海洋局第二海洋研究所浙江杭州310012 中国海洋大学海洋化学理论与工程技术教育部重点实验室山东青岛266100 国家海洋局第一海洋研究所海洋沉积地质与环境地质国家海洋局重点实验室山东青岛200061

在210Pb定年的基础上,对取自浙江沿岸泥质缺氧区的柱样沉积物开展了菜子甾醇、甲藻甾醇、长链烯酮等生物标志化合物分析,根据生物标志化合物含量及比例的分布特征,重建了泥质区110年来浮游植物生产力及群落结构变化。结果表明浙江近岸... 详细信息

在210Pb定年的基础上,对取自浙江沿岸泥质缺氧区的柱样沉积物开展了菜子甾醇、甲藻甾醇、长链烯酮等生物标志化合物分析,根据生物标志化合物含量及比例的分布特征,重建了泥质区110年来浮游植物生产力及群落结构变化。结果表明浙江近岸浮游植物生产力百年来呈上升趋势,自20世纪60年代开始上升,80年代以来有显著增加,浮游植物群落结构则均有甲藻比例上升、硅藻比例下降的趋势。研究认为,浙江沿岸泥质区百年来浮游植物生产力的提高与我国化肥施用量和长江氮的入海通量呈正相关,营养盐N∶P和N∶Si比值的增加导致浮游植物优势种由硅藻向甲藻的转变,说明自20世纪60年代,尤其是自20世纪80年代以来工农业快速发展、大型水利工程建设等人类活动是导致浙江沿岸泥质区海域浮游植物生产力提高及群落结构变化的主要因素。

关键词：浙江沿岸泥质区富营养化和缺氧生物标志物浮游植物生产力

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Free-standing polydopamine films generated in the presence of different metallic ions: the comparison of reaction process and film properties

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RSC ADVANCES 2018年第33期8卷 18347-18354页

作者： Han, xuwen Tang, feng Jin, Zhaoxia Renmin Univ China Dept Chem Beijing 100872 Peoples R China

Polydopamine is widely used in surface modification, nanofiltration, photonic devices and drug delivery. The formation mechanism and properties of polydopamine are modified by the experimental conditions. Herein we demonstrated a comparison study of free-standing polydopamine films generated at the air-solution interface and their corresponding nanoparticles in solutions, in the presence of various metallic cations, Na+, Ca2+, Mg2+ and Co2+. Adding metallic ions influenced the intermediates in dopamine polymerization, and in turn the morphology and properties of the produced free-standing polydopamine films. Moreover, we observed that the polymerization process accompanying the stratification determines the formation of free-standing films at the air-solution interface: the fast polymerization of dopamine in a Co2+ environment leads to a rugged film surface and porous film body, whereas the comparatively slow polymerization of dopamine under conditions of other metallic ions results in a smooth and solid film. In addition, the water contact angles of the upper and lower surface of the polydopamine films were different. This investigation enriches our knowledge of dopamine polymerization in different environments, which is particularly useful for further application of free-standing polydopamine films.

关键词： Polymerization

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