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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 150-158页

作者： Hao Tian Yutian Liu Dong Yang Xiaohui Qin yantao zhang Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinanChina State Grid Shandong Electric Power Research Institute JinanChina China Electric Power Research Institute BeijingChina

The voltage characteristics of a half-wavelength transmission(HWLT)system lack mechanism explanation and systematic *** this paper,both the steady-state and fault voltage characteristics are analyzed and explained based on the wave process *** analysis model is established for HWLT lines and wave propagation equations with different terminal conditions are *** steady-state conditions,voltage profiles along HWLT lines are depicted and partial overvoltage occurs when there is an overload or low-power *** addition,fault voltage characteristics are analyzed under load-rejection or short-circuit *** series resonance overvoltage will happen when short-circuit faults occur at certain positions and its peak value is influenced by grid strength or fault ***,a refined transmission line model is presented to consider non-ideal factors and simulation results demonstrate that geomorphic conditions and electromagnetic environments influence line voltage characteristics to a certain extent.

关键词： Half-wavelength transmission wave process method steady-state voltage fault voltage non-ideal factor

The origin of potential rise during charging of Li-O2 batteries

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Science China Chemistry 2017年第12期60卷 1527-1532页

作者： Limin Guo Jiawei Wang Shunchao Ma yantao zhang Erkang Wang zhangquan Peng State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangehun 130022China University of Chinese Academy of Sciences Beijing 100039China

When aprotic Li-O2 batteries recharge, the solid Li2O2 in the positive electrode is oxidized, which often exhibits a continuous or step increase in the charging potential as a function of the charging capacity, and its origin remains incompletely understood. Here, we report a model study of electro-oxidation of a Li2O2 film on an Au electrode using voltammetry coupled with in situ Raman spectroscopy. It was found that the charging reaction initializes at the positive electrodelLizO2 interface, instead of the previously presumed Li2O2 surface, and consists of two temporally and spatially separated Li2O2 oxidation processes, accounting for the potential rise during charging of Li-O2 batteries. Moreover, the electrode surface-initialized oxidation can disintegrate the Li2O2 film resulting in a loss of Li2O2 into electrolyte solution, which drastically decreases the charging efficiency and highlights the importance of using soluble electro-catalyst for the complete charging of Li-02 batteries.

关键词： aprotic Li-O2 battery reactive site oxygen evolution reaction surface enhanced Raman spectroscopy oxygen electrochemistry

Understanding oxygen electrochemistry in aprotic Li-O_2 batteries

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Green Energy & Environment 2017年第3期2卷 186-203页

作者： Liang Wang yantao zhang Zhenjie Liu Limin Guo zhangquan Peng State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Science and Technology of China University of Chinese Academy of Sciences

In the past decade, the aprotic lithium-oxygen(Li-O_2) battery has generated a great deal of interest because theoretically it can store more energy than today's lithium-ion batteries. Although considerable research efforts have been devoted to the R&D of this potentially disruptive technology, many scientific and engineering obstacles still remain to be addressed before a practical device could be realized. In this review, we summarize recent advances in the fundamental understanding of the O_2 electrochemistry in Li-O_2 batteries, including the O_2 reduction to Li_2O_2 on discharge and the reverse Li_2 O_2 oxidation on recharge and factors that exert strong influences on the redox of O_2/Li_2O_2. In addition,challenges and perspectives are also provided for the future study of Li—O_2 batteries.

关键词： Lithium-oxygen battery Oxygen electrochemistry Mechanism

Fast frequency response of inverter-based resources and its impact on system frequency characteristics

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Global Energy Interconnection 2020年第5期3卷 475-485页

作者： Lining Su Xiaohui Qin Shang zhang yantao zhang Yilang Jiang Yi Han China Electric Power Research Institute Haidian DistrictBeijing 100192P.R.China

The inertia response and primary frequency regulation capability of synchronous grids are declining owing to the increasing penetration of inverter-based resources. The fast frequency response(FFR) of inverter-based resources is an important mitigation option for maintaining grid security under the conditions of low inertia and insufficient primary frequency response capability. However, the understanding and technical characteristics of the FFR of inverter-based resources are still unclear. Aiming at solving the aforementioned problems, this paper proposes a definition for FFR based on the impact mechanism of FFR on system frequency. The performance requirements of FFR are clarified. Then, the effects of FFR on system frequency characteristics are further analyzed based on steady-state frequency deviation, the initial rate of change of frequency, and the maximum transient frequency deviation. Finally, the system requirements for FFR and its application effects are verified by simulating an actual bulk power grid, providing technical support for subsequent engineering application.

关键词： Fast frequency response Rate of change of frequency Frequency deviation ROCOF-based FFR Deviation-based FFR

Regulating cost for renewable energy integration in power grids

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Global Energy Interconnection 2018年第5期1卷 544-551页

作者： Dong zhang Peiyu You Fan Liu Yuhong zhang yantao zhang Chao Feng State Grid Energy Research Institute Co. Ltd. State Grid Economic and Technological Research Institute Co. Ltd. State Grid Hubei Electric Power Co. Ltd. China Electric Power Research Institute Co. Ltd. African Division of SINOHYDRO Bureau 14 Co. Ltd.

To address the issue of climate change caused by the use of polluting, non-renewable energy sources, the use of renewable energy has gained momentum worldwide. Consequently, the increased integration of renewable energy sources into power grids has necessitated the inclusion of flexible capacities in the power systems to solve problems of intermittent and fluctuating characteristics associated with renewable generation outputs. In this work, we study the regulating cost of a power system with high renewable penetration using an improved time-series system production simulation analysis method. The operational cost of the system is considered as the objective function. Three different methods to increase regulating capacities, including using interconnection lines, building additional flexible power capacities, and retrofitting existing thermal power plants, are adopted and simulated to compare the costs of accommodating renewable energy in the system in these cases. Our results indicate that increasing the flexibility of thermal power plants and developing crossregional connection lines are cost-effective methods of increasing renewable energy consumption.

关键词： Renewable energy Power grid Regulating ability Cross-regional connecting lines

Crustal activities recorded incoral reefs in the northwestern South China Sea

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Chinese Science Bulletin 2006年第B12期51卷 89-94页

作者： ZHAN Wenhuan YAO yantao zhang Zhiqiang SUN Zongxun ZHAN Meizhen SUN Longtao LIU Zaifeng CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Coral reefs in the northwest of South China Sea have recorded the information from not only the environmental variation but also the crustal activities there during their development. The main crustal activities correlated with the coral reef development include fault, seismic, and volcano activities, etc. The high-resolution spark seismic profiles in the northwestern South China Sea show that the fault activities in the coral reef region have been clearly recorded, and appear as neonatal faults incising reefs. Earthquakes in the coral reef region are rather intense, especially the two occurring on December, 31, 1994, and January, 10, 1995, around the southwest of Leizhou Peninsula, with the magnitude of 6.1 and 6.2, respectively. They have great influence on the growth of the local coral reefs. Quaternary volcanos are active in the northwestern South China Sea, especially around the southwest of Leizhou Peninsula, and they have obvious control of the coral reef development. Some submarine volcanoes form the substrates of coral reef, while a few emerge above the sea surface and form coral islands.

关键词：南海西北部海域珊瑚礁外壳活动性环境变化

Hierarchical Porous Carbon Nanotube Spheres for High-performance K-O2 Batteries

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Chemical Research in Chinese Universities 2021年第2期37卷 254-258页

作者： DOU Yaying zhang yantao GUO Feng SHEN Yanbin CHEN Gang WEI Yingjin XIE Zhaojun ZHOU Zhen School of Materials Science and Engineering Institute of New Energy Material ChemistryKey Laboratory of Advanced Energy Materials ChemistryMinistry of EducationRenewable Energy Conversion and Storage Center(ReCast)Nankai UniversityTianjin300350P.R.China Key Laboratory of Physics and Technology for Advanced Batteries Ministry of EducationCollege of PhysicsJilin UniversityChangchun130012P.R.China College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang050018P.R.China Zhejiang Chint Electrics Co. Ltd.Shanghai201614P.R.China i-Lab CAS Center for Excellence in NanoscienceSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou215123P.R.China

In view of the ever-growing pressure for green gas emissionreduction,there is an urgent need for renewable *** metal-oxygen batteries,especially lithium-oxygen(Li-o2)batteries,are deemed themost promising energy stora... 详细信息

关键词： Potassium-oxygen battery Potassium superoxide Carbon nanotube

Twist Promotes the Migration of Hepatocellular Carcinoma Cells

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Clinical oncology and cancer researeh 2009年第5期6卷 313-316页

作者： Haibo Han yantao Du Zhiqian zhang Zhao Wei Clinical Laboratory Peking University School of Oncology Beijing Institute for Cancer Research Beijing 100142 China.

OBJECTIVE To study the effect of the Twist gene on the migration of human hepatocellular carcinoma cells and the possible mechanisms involved. METHODS RT-PCR was used to detect expression of the Twist gene in primary （Hep11） and recurrent （Hep12） cell lines from the same HCC patient. Hep11 cells were stably transfected with Twist-cDNA, and Hep12 cells were transiently transfected with Twist RNAi plasmid. Cell migration assays were performed on Twist up-regulated Hep11 cells and Twist RNAi Hep12 cells. RT- PCR and Western blot were used to test the expression of EMT markers. RESULTS Twist was expressed higher level and had increased migration capability in recurrent Hep12 cells than those in primary Hep11 cells. Cell models （Twist-Hep11） in which Twist protein was steadily and highly expressed were obtained. Compared with pcDNA3-Hep11 cells, migration of Twist-Hep11 cells was clearly increased. However, migration of Twist RNAi （Si-Twist-Hep12） Hep12 cells were reduced. Overexpression of Twist in Hep11 cells promoted expression of N-cad and vimentin. CONCLUSION These results indicate that Twist promotes the migration of hepatocellular carcinoma cells in vitro and may play an important role in the upregulation of mesenchymal markers.

关键词： Twist RNA interference gene transfection migration and invasion HCC.

New Damage-locating Method for Bridges Subjected to a Moving Load

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Journal of Ocean University of China 2007年第2期6卷 199-204页

作者： LIU Fushun LI Huajun YU Guangming zhang yantao WANG Weiying SUN Wanqing College of Engineering Ocean University of China Qingdao 266071 P. R. China College of Civil Enginering Qingdao Technologyical University Qingdao 266033 P. R. China Shengli Engineering Consulting Co. Ltd Dongving 257026 P. R. China Center for Engineering Test and Appraisal Qingdao Technological University Qingdao 266033 P. R. China

A new damage-locating method for bridges subjected to a moving load is presented, and a new ‘moving load dam- age-locating indicator’ (MLDI) is introduced. A vehicle is modeled as a moving load, the bridge is simplified as an Euler-Bernoulli beam, and the damage is simulated by a reduction of stiffness properties of the elements. The curvature and MLDI values at each node of the baseline model (undamaged) and the damage model are computed respectively. Then the damage or damages can be located from a sudden change of the MLDI value. The feasibility and effectiveness of the proposed method are validated by nu- merical simulation. The results indicate that the method is effective, being able to not only locate a single damage accurately, but also locate multiple damages in simply-supported bridges, including multiple damages in continuous bridges. The results also indicate that the MLDI can accurately locate damages under 5% measurement noise.

关键词： damage-locating bridge moving load curvature

The Three Forms of the Marxist Philosophy and Their Historical Fate

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Social Sciences in China 2011年第2期32卷 19-34页

作者： Han Qingxiang zhang yantao Marxist Theory Teaching and Research Department Party School of the Central Committee of CPC College of the Humanities Xiamen University

The ＂general problem＂ that Marx＇s philosophy analyzes and aims to solve is capital＇s ownership of labor-power and the emancipation of the proletariat. In the course of exploring this problem, Marx＇s philosophy developed three basic, organically integrated forms： the popular, the scholarly and the political. However, the post-Marx history of Marxist philosophy has seen these three forms evolve differently and meet with different fates. The situation in contemporary China can be summarized as follows. The popular form is proposed but not fully realized; the scholarly form is robust but estranged from politics and the public; and the political form is prominent but needs further academic support and popular recognition. For the healthy development of Marxist philosophical research in contemporary China, we must not only clarify the integral structure of Marx＇s philosophy but also create an ＂ecological environment＂ favorable to its sustainable development with a view to facilitating the benign interaction of the three basic forms.

关键词： Marxist philosophy popular form scholarly form political form