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Load and velocity boundaries of oil-based superlubricity using 1,3-diketone

Friction 2023年第5期11卷 704-715页

作者： yuyang yuan Tobias AMANN Yuwen XU Yan ZHANG Jingfu CHEN Chenqing yuan Ke LI School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Reliability Engineering Institute National Engineering Research Center for Water Transport SafetyMOSTWuhan 430063China Fraunhofer Institute for Mechanics of Materials IWM Freiburg 79108Germany

The clarification of the critical operating conditions and the failure mechanism of superlubricity systems is of great significance for seeking appropriate applications in *** this work,the superlubricity region of 1,3-diketone oil EPND(1-(4-ethyl phenyl)nonane-1,3-dione)on steel surfaces was identified by performing a series of ball-on-disk rotation friction tests under various normal loads(3.5–64 N)and sliding velocities(100–600 mm/s).The result shows that beyond certain loads or velocities superlubricity failed to be reached due to the following negative effects:(1)Under low load(≤3.5 N),insufficient running-in could not ensure good asperity level conformity between the upper and lower surfaces;(2)the high load(≥64 N)produced excessive wear and big debris;(3)at low velocity(≤100 mm/s),the weak hydrodynamic effect and the generated debris deteriorated the lubrication performance;(4)at high velocity(≥500 mm/s),oil migration occurred and resulted in oil *** order to expand the load and velocity boundaries of the superlubricity region,an optimized running-in method was proposed to avoid the above negative *** initially operating a running-in process under a suitable combination of load and velocity(e.g.16 N and 300 mm/s)and then switching to the target certain higher or lower load/velocity(e.g.100 N),the superlubricity region could break through its original *** result of this work suggests that oil-based superlubricity of 1,3-diketone is a promising solution to friction reduction under suitable operating conditions especially using a well-designed running-in strategy.

关键词： macroscopic superlubricity 1,3-diketone oil running-in process load and velocity boundaries

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Lipid Evidence for Oil Depletion by Sulfate-Reducing Bacteria during U Mineralization in the Dongsheng Deposit

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Journal of Earth Science 2018年第3期29卷 556-563页

作者： Tiankai Wang Lei Jiang Chunfang Cai yuyang yuan Yongdong Zhang Lianqi Jia Shuangling Chen Key Laboratory of Petroleum Resources Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China

Fatty acids were extracted from fluid inclusions, and analyzed for distribution and individual 613C values to determine if there exists sulfate-reducing bacteria （SRB） and what substrates SRB depleted during U mineralization in the Dongsheng deposit. The 10-methylhexadecanoic acid （10Mel6：0） has been detected from most of the samples using GC-MS based on relative retention time and co-injection of standard 10Me16：0 compound. Samples with higher 10Me16： 0 concentrations, show higher U contents. The presence of 10Mel6：0 along with iso-ω7-cis-heptadecenoic acid （i17：1ω7c） and ω7-cisoctadecenoic acid （18：1ω7c） in the fluid inclusions may indicate the occurrence of SRB during the U mineralization. Saturated fatty-acids and unsaturated fatty-acids detected in this study have individual δ^13C values from-30.3‰ to-28.5‰ and-30.5‰ to-27.9‰, respectively. These values are close to those of n-alkanes of the associated oils and the bulk oils, but significantly distinct from methane, thus the oils are concluded to have been used as substrate for the microorganisms to survive on. This proposal is supported by oil biodegradation and ore-stage calcite cement with δ^13C values from-1.4‰ to-17.2‰.

关键词： fatty acids sulfate-reducing bacteria(SRB) individual lipid carbon isotope sulfur isotope uranium deposit.

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Redox condition during Ediacaran–Cambrian transition in the Lower Yangtze deep water basin, South China: constraints from iron speciation and δ^(13) Corg in the Diben section, Zhejiang

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Chinese Science Bulletin 2014年第28期59卷 3638-3649页

作者： yuyang yuan Chunfang Cai Tiankai Wang Lei Xiang Lianqi Jia Yan Chen Key Laboratory of Petroleum Resource Research Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Nanjing Institute of Geological Paleontology Chinese Academy of Sciences

Cherts of the Piyuancun Formation and black mudstones of the Hetang Formation in Diben Town, Kaihua County, Zhejiang were deposited in a deep water basin of the Lower Yangtze area during the Ediacaran–Cambrian transition(E–C transition), offering an opportunity to reconstruct the ancient redox condition of the deep water basin. Total 53 samples were collected and analyzed for iron speciation, including pyrite iron(FePy), carbonate associated iron(FeCarb), iron oxide and hydroxide(FeOx),magnetite iron(FeMag) and total iron(FeT) as well as d13 Corgto gain a deeper understanding of specific redox condition during the period. The results show that(1) most samples have pyrite concentration \1 %, with the FePy/FeHR ratio ranging from \0.01 to 0.81(mostly \0.5), and the FeHR/FeT ratio between 0.39 and 0.93(mostly [0.5).(2) The E–C boundary in the Diben section occurred at the maximum negative excursion of organic carbon isotope within the Piyuancun Formation, which can be correlated with other sections by using d13 Corg. We thus concluded that the relatively high content of highly reactive iron and low content of pyrite iron in the Diben section indicate a minor occurrence of H2 S and a predominance of anoxic and ferruginous environment, which is similar to other reported sections such as the Longbizui and Yanwutan sections, western Hunan. In addition, oxygen concentration in sea water showed an increasing trend in the interval corresponding to the bottom and upper layer of the Hetang Formation as indicated by the FeHR/FeT ratio, which decreased from 0.7 to 0.38, however, it was not great enough to oxidize the whole deep water. Therefore, during the E–C transition deep water basin in South China was most likely an anoxic and ferruginous enrironment, which prevented metazoon from the evolution in the deep water basin. Our work offers an important reference to better understanding of the spatiotemporal occurrence and dynamic processes of the ‘‘Cambrian Explosion''.

关键词：氧化还原状态寒武纪大爆发长江下游地区深水盆地中国南方铁形态迪卡浙江

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Recentprogress in thebiomedical application of PEDOT:PSS hydrogels

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Chinese Chemical Letters 2024年第10期35卷 13-27页

作者： Binhan Zhao Zheng Li Lan Zheng Zhichao Ye yuyang yuan Shanshan Zhang Bo Liang Tianyu Li National Engineering Research Center of Innovation and Application of Minimally Invasive Instruments Sir Run Run Shaw HospitalSchool of MedicineZhejiangUniversityHangzhou 310028China Department of Translational Medicine Clinical Research Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310028China Biosensor National Special Laboratory College of Biomedical Engineering and Instrument ScienceZhejiang UniversityHangzhou 310028China School of Medicine Zhejiang UniversityHangzhou 310028China

Bioelectronics have gained substantial research attention owing to their potential applications in health monitoring and diagnose,and greatly promoted the development of ***,poly(3,4-ethylenedioxythiophene):polystyrene sulfonate(PEDOT:PSS)hydrogels have arose as a promising candi-date for the next-generation bioelectronic interface due to its high-conductivity,versatility,flexibility and *** this review,we highlight the recent advances of PEDOT:PSS hydrogels,including the gelation methods and modification strategies,and summarize their wide applications in different type of sensors and tissue engineering in *** expect that this work will provide valuable information regarding the functionalizations and applications of PEDOT:PSS hydrogels.

关键词： Conductingpolymer PEDOT:PSS hydrogels Conjugatedpolymer Gelation methods Biomedicalapplication

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The Ocean Redox State Evolution and Its Controls during the Cambrian Series 1–2: Evidence from Lijiatuo Section, South China

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Journal of Earth Science 2016年第2期27卷 255-270页

作者： Lei Xiang Chunfang Cai Xunyun He Lei Jiang yuyang yuan Tiankai Wang Lianqi Jia Lei Yu Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences Hangzhou Research Institute of Geology Petro China Exploration and Development Research Institute of Petro China Changqing Oilfield Company Petro China

Well-exposed Lijiatuo Section was chosen to explore the temporal evolution and controls of the oceanic redox state, primary productivity and seawater sulfate levels during the Cambrian Series 1-2, South China. This section consists of Xiaoyanxi Formation（Fm.） mudstones and Liuchapo Fm. cherts that deposited in the slope and basin environment. Five oxic-anoxic cycles were identified based on V/Sc, Th/U and the enrichment factors of Mo, U, V, Ni and Cu. The Middle-Upper Liuchapo Fm. and the Middle Xiaoyanxi Fm. were deposited under oxic-suboxic conditions, and the rest of the strata were under anoxic conditions. The Re/Mo ratio demonstrated that the oxic-suboxic conditions in the Middle Xiaoyanxi Fm. were accompanied by transient sulfidic conditions, and the rest of the section was underanoxic and non-sulfidic conditions. All the TOC and the enrichment factors of Ba, Ni, Cu, Zn and Cd demonstrated that both the sinking and burial flux of organic matter（OM） in Liuchapo Fm. were lower than that in the overlying Xiaoyanxi Fm. The highest sinking and burial flux of OM in the Xiaoyanxi Fm. appeared at its lower parts; however, the lowest sinking and burial flux of OM in the Xiaoyanxi Fm. appeared in its middle parts. TOC/TS, TS and the vertical trend of δ^（34）S_（py） demonstrated that the seawater was dominated by low oceanic sulfate levels, which resulted in the absence of free H_2S. The rise of the atmospheric oxygen content may be the principal driver for the associated, transient suboxic-oxic and nearly sulfidic environment in the middle Xiaoyanxi Fm.

关键词： trace element redox state seawater sulfate level Cambrian Series 1-2 South China.

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信息化背景下智慧乡村的特征、类型及其实践路径

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现代经济探讨 2021年第4期 126-132页

作者：袁宇阳华东师范大学社会发展学院上海200241

在信息化背景下,推进智慧乡村发展,提高乡村数字化水平,是缩小城乡数字鸿沟,促进城乡融合发展,实现乡村振兴的重要途径和未来趋势。研究表明,智慧乡村具有信息化、多元化和专业化这三个核心特征,旨在促进乡村社会的全面发展。智慧乡村... 详细信息

在信息化背景下,推进智慧乡村发展,提高乡村数字化水平,是缩小城乡数字鸿沟,促进城乡融合发展,实现乡村振兴的重要途径和未来趋势。研究表明,智慧乡村具有信息化、多元化和专业化这三个核心特征,旨在促进乡村社会的全面发展。智慧乡村具有多种形式,主要包括农业型、旅游型和能源型这三种基本类型。全面推进中国智慧乡村发展,实现乡村振兴,必须因地制宜,做好智慧乡村发展的科学规划,协调好多元参与主体的利益,大力推动乡村社会的信息化建设,并积极构建农民与技术的和谐关系。

关键词：智慧乡村技术信息化乡村振兴

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嵌入性视角下乡村数字治理的多重困境及其破解路径

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云南民族大学学报（哲学社会科学版） 2023年第4期40卷 115-122页

作者：袁宇阳广州大学公共管理学院广东广州510006

推进乡村数字治理是提升乡村治理效率的重要路径。从嵌入性视角出发,在数字治理技术供给乡村社会的过程中,还需要合理的认知、行政、文化以及关系的嵌入。然而,由于数字鸿沟下农民数字认知不足、“数字锦标赛”下的“数字政绩”激励、... 详细信息

推进乡村数字治理是提升乡村治理效率的重要路径。从嵌入性视角出发,在数字治理技术供给乡村社会的过程中,还需要合理的认知、行政、文化以及关系的嵌入。然而,由于数字鸿沟下农民数字认知不足、“数字锦标赛”下的“数字政绩”激励、“外生性”数字治理的地方排斥、“数字脱域”下“基层-农民”关系脱嵌等原因,当前我国乡村数字治理存在一定的认知嵌入不足、行政嵌入过度、文化嵌入缺位以及关系嵌入弱化等多重困境。应该有序推进数字治理、普及乡村数字教育,改善乡村数字治理考核体系,促进乡村本土治理文化内容融入数字治理,多途径增进乡村数字治理中的“基层-农民”关系,以此塑造良好的嵌入性环境,真正实现有效乡村数字治理。

关键词：嵌入性乡村治理数字治理数字乡村

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“大国小农”视角下农业数字化转型的现实挑战及推进策略

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现代经济探讨 2024年第7期 124-132页

作者：袁宇阳广州大学公共管理学院广州大学乡村振兴研究院广州510006

农业数字化转型是中国式农业农村现代化的必由之路。从“大国小农”的视角出发,中国农业数字化转型建立在广大小农的农业数字化转型基础之上。基于结构化理论,小农在农业生产方面往往具有小农经济结构下的“惯例”,而农业数字化转型将... 详细信息

农业数字化转型是中国式农业农村现代化的必由之路。从“大国小农”的视角出发,中国农业数字化转型建立在广大小农的农业数字化转型基础之上。基于结构化理论,小农在农业生产方面往往具有小农经济结构下的“惯例”,而农业数字化转型将重塑小农经济结构,改变小农的农业生产行动,可能带来小农传统“惯例”与现代数字农业之间的区隔以及结构性矛盾,使得小农经济向农业数字化转型过程中面临诸多现实挑战。研究发现,“大国小农”视角下的农业数字化转型存在一定的高成本数字与低投入小农、同质性数字与异质性小农、大规模数字与小规模小农、变革性数字与保守性小农以及关联性数字与分散化小农等之间的内在矛盾。应该通过降低小农数字化转型投入成本,提供差异性数字化转型方案,创新小规模农业数字化转型方式,构建渐进性数字化转型模式,增进小农与各农业主体关联性等策略,将部分小农“惯例”融入数字化转型中,助力“大国小农”的农业数字化转型。

关键词： “大国小农” 农业数字化转型农业农村现代化惯例

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国内大循环背景下乡村振兴的实践转向与路径探索

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当代经济管理 2021年第7期43卷 29-34页

作者：袁宇阳华东师范大学社会发展学院上海200241

双循环新发展格局是建立在国内大循环基础之上的,而构建国内大循环体系的关键之一在于广大乡村的发展。需要厘清乡村振兴与国内大循环构建之间的内在关系,以此促进二者的有效衔接。研究发现,乡村振兴是构建国内大循环的根本基础,全面推... 详细信息

双循环新发展格局是建立在国内大循环基础之上的,而构建国内大循环体系的关键之一在于广大乡村的发展。需要厘清乡村振兴与国内大循环构建之间的内在关系,以此促进二者的有效衔接。研究发现,乡村振兴是构建国内大循环的根本基础,全面推进乡村振兴,有助于降低外部依赖,扩大市场规模,拉动内部消费,激活就业市场,构建信任体系,从而促进经济内循环发展。在国内大循环构建的背景下,乡村振兴需要进行一定的实践转向,观念要由"旧"到"新",动力要由"外"到"内",任务要由"多"到"精",思路要由"点"到"面",目标要由"量"到"质"。研究认为,只有深化农村改革,激发内生动力,明确发展方向,加强合作关系,注重发展质量,才能让乡村振兴战略的实施不仅可以促进乡村发展,还可以更好地嵌入到双循环新发展格局的构建中。

关键词：乡村振兴国内大循环双循环新发展格局内生发展

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重庆市江津区表层土壤中稀土元素含量与分布特征

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中国稀土学报 2020年第2期38卷 215-224页

作者：刘永林雒昆利袁余洋重庆师范大学地理与旅游学院重庆师范大学GIS应用研究重点实验室重庆401331 中国科学院地理科学与资源研究所北京100101 遵义师范学院工学院贵州遵义563006

为研究重庆市江津区表层土壤中稀土元素(REE)含量和空间分布特征,采集156件土壤样品,用电感耦合等离子体质谱仪(ICP-MS)测定其稀土元素含量。采用统计学和地质统计学分析了表层土壤中稀土元素含量和空间分布特征,结果表明:江津区表层土... 详细信息

为研究重庆市江津区表层土壤中稀土元素(REE)含量和空间分布特征,采集156件土壤样品,用电感耦合等离子体质谱仪(ICP-MS)测定其稀土元素含量。采用统计学和地质统计学分析了表层土壤中稀土元素含量和空间分布特征,结果表明:江津区表层土壤中REE含量范围为99.06~222.28μg·g^-1,平均值149.07μg·g^-1,低于中国土壤REE背景值(163.86μg·g-1)。江津区表层土壤的球粒陨石标准化曲线呈现向右倾斜的轻稀土富集型。δEu和δCe平均值分别为0.57和0.91,表现出明显的Eu负异常和微弱的Ce负异常。不同地质时代地层上覆表层土壤中REE含量具有显著差异性(p=0.035<0.05),下白垩统窝头山组(K1w)和侏罗系(J)地层上覆表层土壤中稀土元素含量高于三叠系(T)地层。江津区中西部地区表层土壤中稀土元素总量较高。

关键词：稀土元素表层土壤重庆市江津区空间分布

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