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An improved strategy for out-of-step oscillation separation devices based on apparent impedance angle applied to a series compensated line

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Protection and Control of Modern Power Systems 2022年第1期7卷 316-323页

作者： Haibo Xu Yupeng Cai xiaolei qu Zhiwei Dong NARI Group Corporation/State Grid Electric Power Research Institute Nanjing 210003China Electric Power Research Institute of State Grid Liaoning Electric Power Co. LtdShenyang 110006China

Out-of-step oscillation separation devices based on apparent impedance angle trajectory are widely used in the power grid in China,and their reliability is of great *** this paper,the influence mechanism of series compensation on apparent impedance angle trajectory is *** reveals that series compensation capacitors reduce the equivalent impedance angle and consequently the apparent impedance angle cannot pass through all four zones,resulting in the risk of failure for the separation devices.A revised method of apparent impedance angle based on compensation principle is discussed,and then an improved out-of-step oscillation detection criterion is *** view of the fact that the apparent impedance angle at the moment of maximum current is equal to the equivalent impedance angle during an oscillation process,a practical algorithm based on the compensated apparent impedance angle is *** tests are conducted to verify the effectiveness of the new criterion,considering transmission lines with a high series compensation level.

关键词： Out-of-step oscillation separation Series compensated line Apparent impedance angle Compensated impedance angle

Rational Design of Robust and Universal Aqueous Binders to Enable Highly Stable Cyclability of High-Capacity Conversion and Alloy-Type Anodes

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Energy & Environmental Materials 2023年第5期6卷 260-268页

作者： Yuzhu Yao xiaolei qu Linming Zhou Yongfeng Liu Zijian Hong Yongjun Wu Zhenguo Huang Jianjiang Hu Mingxia Gao Hongge Pan State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province and School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an 710021China School of Civil&Environmental Engineering University of Technology Sydney81 BroadwayUltimo New South Wales 2007Australia School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China

The development of high-performance binders is a simple but effective approach to address the rapid capacity decay of high-capacity anodes caused by large volume change upon lithiation/***,we demonstrate a unique organic/inorganic hybrid binder system that enables an efficient in situ crosslinking of aqueous binders(e.g.,sodium alginate(SA)and carboxymethyl cellulose(CMC))by reacting with an inorganic crosslinker(sodium metaborate hydrate(SMH))upon vacuum *** resultant 3D interconnected networks endow the binders with strong adhesion and outstanding self-healing capability,which effectively improve the electrode integrity by preventing fracturing and exfoliation during cycling and facilitate Li^(+)ion *** anodes fabricated from the commercial microsized powders with the SA/0.2SMH binder maintain 1470 mAh g^(-1)of specific capacity at 100 mA g^(-1)after 200 cycles,which is 5 times higher than that fabricated with SA binder alone(293 mAh g^(-1)).Nearly,no capacity loss was observed over 500 cycles when limiting discharge capacity at 1500 mAh g^(-1).The new binders also dramatically improved the performance of Fe_(2)O_(3),Fe_(3)O_(4),NiO,and Si electrodes,indicating the excellent *** finding represents a novel strategy in developing high-performance aqueous binders and improves the prospect of using high-capacity anode materials in Li-ion batteries.

关键词： anode materials binders cycling stability in situ crosslinking lithium-ion batteries

Hydrothermal conversion of fructose to lactic acid and derivatives:Synergies of metal and acid/base catalysts

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Chinese Journal of Chemical Engineering 2023年第1期53卷 381-401页

作者： Tianqi Fang Mengyuan Liu Zhaozhe Li Li Xiong Dongpei Zhang Kexin Meng xiaolei qu Guangyu Zhang Xin Jin Chaohe Yang State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumQingdao 266580China Sinopec Research Institute of Safety Engineering Qingdao 266580China

With increasing strict regulation on single-use plastics,lactic acid(LA)and alkyl lactates,as essential monomers for bio-degradable polylactic acid(PLA)plastic products,have gained worldwide attention in both academia and *** LA is still dominantly produced through fermentation processes from start,chemical synthesis from cellulosic biomass remains a grand challenge,owing to poor selectivity in activating CAH and CAC bonds in sugar *** our best knowledge,recent publications have been focused on hydrothermal conversion of glucose to LA,while this review summarizes the highlights on direct thermal conversion of fructose as starting material to LA and *** particular,the synergies of metal/metal cations and acid/base catalysts will be critically revised on retro-aldol and dehydration *** work will provide insights into rational design of active and selective catalysts for the production of carboxylic acids from biomass feedstocks.

关键词： Fructose Lactic acid Alkyl lactate Thermal conversion

Molecular signature of soil organic matter under different land uses in the Lake Chaohu Basin

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Eco-Environment & Health 2022年第4期1卷 212-218页

作者： Han Gao Huixin Li Chen Lin Pedro J.J.Alvarez Caroline A.Masiello Dongqiang Zhu Ao Kong xiaolei qu State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China School of Finance Nanjing University of Finance and EconomicsNanjing 210023China Key Laboratory of Watershed Geographic Sciences Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control Nanjing Institute of Environmental SciencesMinistry of Ecology and Environment of ChinaNanjing 210042China Department of Civil and Environmental Engineering Rice UniversityHouston TX 77005USA Department of Earth Environmental and Planetary SciencesRice UniversityHouston TX 77005USA School of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The concentration and molecular composition of soil organic matter(SOM)are important factors in mitigation against climate change as well as providing other ecosystem *** quantitative understanding of how land use influences SOM molecular composition and associated turnover dynamics is limited,which underscores the need for high-throughput analytical approaches and molecular marker signatures to clarify this *** a high-throughput untargeted mass spectrometry screening and molecular markers,we show that forest,farmland and urban land uses result in distinct molecular signatures of SOM in the Lake Chaohu *** markers indicate that forest SOM has abundant carbon contents from vegetation and condensed organic carbon,leading to high soil organic carbon(SOC)*** SOM has moderate carbon contents from vegetation,and limited content of condensed organic carbon,with SOC significantly lower than that of forest *** SOM has high abundance of condensed organic carbon markers due to anthropogenic activities but relatively low in markers from ***,urban soils have the highest black carbon/SOC ratio among these land ***,our results suggested that the molecular signature of SOM varies significantly with land use in the Lake Chaohu Basin,influencing carbon *** strategy of molecular fingerprinting and marker discovery is expected to enlighten further research on SOM molecular signatures and cycling dynamics.

关键词： High-throughput untargeted mass spectrometry screening Mass spectrum processing algorithm Soil organic matter Molecular signature Land use

融合双注意力机制EfficientNet的沥青路面状态分类方法

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机械工程学报 2022年第24期58卷 211-222页

作者：杨炜黄立红屈晓磊长安大学汽车学院西安710064 北京航空航天大学仪器科学与光电工程学院北京100191

针对现有EfficientNet模型应用于沥青路面状态分类时,卷积操作易导致高层特征信息丢失问题,在现有EfficientNet模型的深层结构中引入一种双注意力机制,包含通道注意力模块和位置注意力模块,借助Sigmoid线性单元(Sigmoid linear unit,Si... 详细信息

针对现有EfficientNet模型应用于沥青路面状态分类时,卷积操作易导致高层特征信息丢失问题,在现有EfficientNet模型的深层结构中引入一种双注意力机制,包含通道注意力模块和位置注意力模块,借助Sigmoid线性单元(Sigmoid linear unit,SiLU)激活函数和余弦学习率衰减策略,提出一种融合双注意力机制EfficientNet(Dual attention network based on EfficientNet,DAEfficientNet)的沥青路面状态分类方法。首先,建立不同天气下5种沥青路面共5938张图像作为数据集,积雪样本来自开源数据集(Canadian adverse driving conditions dataset,CADCD)。然后,对所提出模型进行训练,并得到沥青路面图像分类结果。最后,利用准确率(Accuracy)、精确率(Precision)、召回率(Recall)、F1 score和特异度(Specificity),将所提出模型与其他现有卷积神经网络模型进行分类效果对比分析。试验结果表明:所提出模型优于其他对比模型,能准确、有效地对不同天气下的沥青路面状态进行分类。

关键词：卷积神经网络双注意力机制沥青路面路面分类

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Future research needs for environmental science in China

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Geography and Sustainability 2021年第3期2卷 234-242页

作者： Dongqiang Zhu Weiqiang Chen xiaolei qu Yuming Zheng Jun Bi Haidong Kan Yongming Luo Guangguo Ying Eddy Y.Zeng Fangjie Zhao Lingyan Zhu Yongguan Zhu Shu Tao School of Urban and Environmental Sciences Peking UniversityBeijing 100871China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityJiangsu 210023China Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China School of Public Health Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of HealthFudan UniversityShanghai 200433China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China The Environmental Research Institute Ministry of Education Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 511443China Jiangsu Key Laboratory for Organic Waste Utilization Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource UtilizationCollege of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Tianjin Key Laboratory of Remediation&Pollution Control for Urban Ecological Environment Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China

Environmental science is an interdisciplinary science developed in the process of understanding and solving ecolog-ical and environmental *** order to tackle these problems,environmental science research is expected to reveal the source,behavior,fate,exposure,and risks of pollutants in the environment and develop potential solutions to control *** provides the scientific basis for decision-makers to establish environmental and economic poli-cies,and promote concerted efforts for the sustainable development of ***,we articulate the development patterns,challenges,and future research needs of environmental science in China based on literature review and expert panel *** science research has evolved significantly in the past decade with an increas-ing diversity of environmental pollutants and health impacts,new technologies and methods,deepening fusion of multiple disciplines,and emerging solutions for pollution *** future development relies on the advances in our knowledge on the fate and transport of pollutants,regional environmental processes,ecotoxicological effects,environmental exposure and health effects,environmental analysis and monitoring,source control and reduction,environmental remediation,as well as environmental risk *** each of these fields,we summarize the significant challenges and highlight the research demands for *** on the status quo of China’s environmen-tal science research and future needs,we provide recommendations to promote its future development,including encouraging innovation and interdisciplinary research,providing decision support for national needs,encouraging international collaboration,and improving collaboration mechanisms.

关键词： Environmental science China Challenges Opportunities Research needs

基于紫外⁃可见光谱和机器学习方法的溶解性有机质吸附预测模型研究

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南京大学学报（自然科学版） 2021年第3期57卷 356-363页

作者：崔鹤刘昆瞿晓磊污染控制与资源化研究国家重点实验室南京大学环境学院南京210023

有机化合物在溶解性有机质(Dissolved Organic Matter,DOM)上的吸附行为显著影响其环境归趋和生物有效性.以标化的DOM紫外⁃可见光谱和有机化合物的正辛醇⁃水分配系数为特征,运用随机森林算法,建立有机碳标化分配系数(KOC)的预测模型.结... 详细信息

有机化合物在溶解性有机质(Dissolved Organic Matter,DOM)上的吸附行为显著影响其环境归趋和生物有效性.以标化的DOM紫外⁃可见光谱和有机化合物的正辛醇⁃水分配系数为特征,运用随机森林算法,建立有机碳标化分配系数(KOC)的预测模型.结果显示,随机森林模型在全部来源DOM上的预测精度显著高于目前普遍使用的线性自由能模型,但略低于两相体系模型.随机森林模型对土壤和泥炭来源的DOM吸附预测精度显著优于其他模型,说明随机森林模型具有很好的适用性.根据随机森林模型输出的特征重要性,发现模型学习到了表征DOM分子量大小、腐殖化程度以及苯环上取代基类型的光谱特征.通过特征选择,发现模型使用少数重要性较高的特征可以达到使用全谱的效果,即使在只选取两个波长时,预测精度依然显著优于线性自由能模型.由于DOM的紫外⁃可见光谱可原位实时分析,基于紫外⁃可见光谱和机器学习方法的预测模型未来可进行原位及高通量KOC时空规律解析,从而实现更准确更精细的风险评估与管理.

关键词：溶解性有机质有机碳标化分配系数预测模型紫外⁃可见光谱机器学习

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山西平鲁败虎堡风电场并网线动态载流量研究

电网技术 2016年第5期40卷 1400-1405页

作者：王天正朱石晶郭瑞宙曲晓蕾国网山西省电力公司电力科学研究院山西省太原市030000 国电南瑞科技股份有限公司江苏省南京市211100

在现有的输电线路上,由于对输电线沿线环境及输电线状态等参数信息获取的有限性,电网公司对线路载流量的限定往往是保守和静态的。这种保守的载流量设定限制了线路输送能力的提升,降低了线路的利用效率,是输电线路效能发挥的一种约束。... 详细信息

在现有的输电线路上,由于对输电线沿线环境及输电线状态等参数信息获取的有限性,电网公司对线路载流量的限定往往是保守和静态的。这种保守的载流量设定限制了线路输送能力的提升,降低了线路的利用效率,是输电线路效能发挥的一种约束。以山西平鲁败虎堡风电场并网线为例,对架空输电线的动态载流量进行了计算,并对比该线路的动态载流量与静态载流量。从计算结果来看,败虎堡风电场并网线载流量在冬季气温较低、风速较大的时间段内,在运行温度不突破最大运行温度的前提下,仍然有较大提升空间,动态载流量比静态载流量大76.8%。

关键词：风力发电风电场并网线静态载流量动态载流量载流量提升

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溶解态黑碳的环境过程研究

化学进展 2017年第9期29卷 1042-1052页

作者：魏晨辉付翯云瞿晓磊朱东强南京大学环境学院污染控制与资源化研究国家重点实验室南京210046 北京大学城市与环境学院北京100871

溶解态黑碳是黑碳连续体中可溶解于水的组分,是连接陆地土壤和海洋底泥两个主要黑碳库的关键纽带。溶解态黑碳也是天然可溶性有机质的重要组分,富含芳香微域结构和羧基、羟基、羰基等功能性官能团,具有较高的反应活性,可介导污染物在环... 详细信息

溶解态黑碳是黑碳连续体中可溶解于水的组分,是连接陆地土壤和海洋底泥两个主要黑碳库的关键纽带。溶解态黑碳也是天然可溶性有机质的重要组分,富含芳香微域结构和羧基、羟基、羰基等功能性官能团,具有较高的反应活性,可介导污染物在环境中的分配和转化过程。因此,研究溶解态黑碳的环境地球化学行为对研究全球碳循环以及污染物的环境归趋和效应都具有重要意义,已成为了相关领域的前沿和热点。本文综述了十余年以来溶解态黑碳在环境过程方面的研究进展,重点阐述了溶解态黑碳的定性、定量分析方法,在环境中的含量和空间分布、结构特征、环境转化过程,以及其对污染物吸附、氧化还原转化、光转化等环境行为的影响,并在此基础上对溶解态黑碳的未来研究方向进行了展望。

关键词：溶解态黑碳时空分布结构特征污染物环境效应作用机制