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Narrative Graph:Telling Evolving Stories Based on Event-centric Temporal Knowledge Graph

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Journal of Systems Science and Systems Engineering 2023年第2期32卷 206-221页

作者： zhihua yan Xijin Tang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China School of Management Science and Engineering Shanxi University of Finance and EconomicsTaiyuan030006China University of Chinese Academy of Sciences Beijing100039China

As the main channel for people to obtain information and express their opinions,online media generate a huge amount of unstructured news documents every day and make it difficult for people to perceive major societal events and grasp the evolution of events.Previous studies on storyline generation are generally based on document clustering without considering event arguments and relations between events.Event-centric knowledge graph has been used to facilitate the construction of news documents to form structured event representation.Although some studies have attempted to construct timelines based on event-centric knowledge graphs,it is difficult for timelines to depict the complex structures of event evolution.In this paper,we try to represent news documents as an event-centric knowledge graph,and compress the whole knowledge graph into salient complex events in temporal order to generate storylines named narrative graph.We first collect news documents from news platforms,construct an event ontology,and build an event-centric knowledge graph with temporal relations.Graph neural network is used to detect events,while BERT fine-tuning is leveraged to identify temporal relations between events.Then,a novel generation framework of narrative graph with constraints of coherence and coverage is proposed.In addition,a case study is implemented to demonstrate how to utilize narrative graph to analyze real-world event.The experiment results show that our approach significantly outperforms the baseline approaches.

关键词： Storyline event-centric knowledge graph event evolution community detection

Chemoproteomics reveals the epoxidase enzyme for the biosynthesis of camptothecin in Ophiorrhiza pumila

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Journal of Integrative Plant Biology 2024年第6期66卷 1044-1047页

作者： Tong Zhang yan Wang Shiwen Wu Ernuo Tian Chengshuai yang zhihua Zhou Xing yan Pingping Wang CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences

Camptothecin is one of the most commonly used anticancer drugs worldwide, yet the downstream biosynthetic route from strictosidine to camptothecin has remained unclear for more than half a century. Here,we searched for proteins involved in camptothecin biosynthesis from the camptothecin-producing plant Ophiorrhiza pumila by chemoproteomics and identified Op CYP716E111.

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Effects of impregnation sequence on the NH_(3)-SCR activity and hydrothermal stability of a Ce-Nb/SnO_(2) catalyst

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Journal of Environmental Sciences 2024年第4期138卷 450-457页

作者： Ying Zhu Wenpo Shan zhihua Lian Jingjing Liu yan Zhang Hong He Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Zhejiang Key Laboratory of Urban Environmental Processes and Pollution Control Ningbo Urban Environment Observation and Research StationInstitute of Urban EnvironmentChinese Academy of SciencesNingbo 315800China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Hydrothermal stability is crucial for the practical application of deNO_(x)catalyst on diesel vehicles,for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).SnO_(2)-based materials possess superior hydrothermal stability,which is attractive for the development of NH_(3)-SCR catalyst.In this work,a series of Ce-Nb/SnO_(2)catalysts,with Ce and Nb loading on SnO_(2)support,were prepared by impregnation method.It was found that,the NH_(3)-SCR activities and hydrothermal stabilities of the Ce-Nb/SnO_(2)catalysts significantly varied with the impregnation sequences,and the Ce-Nb(f)/SnO_(2) catalyst that firstly impregnated Nb and then impregnated Ce exhibited the best performance.The characterization results revealed that CeNb(f)/SnO_(2)possessed appropriate acidity and redox capability.Furthermore,the strong synergistic effect between Nb and Sn species stabilized the structure and maintained the dispersion of acid sites.This study may provide a new understanding for the effect of impregnation sequence on activity and hydrothermal stability and a new environmental-friendly NH_(3)-SCR catalyst with potential applications for NO_(x)removal from diesel and hydrogenfueled engines.

关键词： NO_(x)emission control NH_(3)-SCR Hydrothermal stability Ce-Nb/SnO_(2)catalyst Impregnation sequence

Interface sites on vanadia-based catalysts are highly active for NO_(x) removal under realistic conditions

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Journal of Environmental Sciences 2024年第2期136卷 523-536页

作者： Zhihui Lv Guangzhi He Wenshuo Zhang Jingjing Liu zhihua Lian yang yang Zidi yan Guangyan Xu Wenpo Shan Yunbo Yu Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China Ningbo Research Center for Urban Environment Chinese Academy of SciencesNingbo 315800China

TiO_(2)-supported V_(2)O_(5)catalysts are commonly used in NO_(x)reduction with ammonia due to their robust catalytic performance.Over these catalysts,it is generally considered that the active species are mainly derived from the vanadia species rather than the intrinsic structure of V-O-Ti entities,namely the interface sites.To reveal the role of V-O-Ti entities in NH_(3)-SCR,herein,we prepared TiO_(2)/V_(2)O_(5)catalysts and demonstrated that V-O-Ti entities were more active for NO_(x)reduction under wet conditions than the V sites(V=O)working alone.On the V-O-Ti entities,kinetic measurements and first principles calculations revealed that NH_(3)activation exhibited a much lower energy barrier than that on V=O sites.Under wet conditions,the V-O-Ti interface significantly inhibited the transformation of V=O to V-OH sites thus benefiting NH_(3)activation.Under wet conditions,meanwhile,the migration of NH_(4)^(+)from Ti site neighboring the V-O-Ti interface to Ti site of the V-O-Ti interface was exothermic;thus,V-O-Ti entities together with neighboring Ti sites could serve as channels linking NH_(3)pool and active centers for activation of NH_(4)^(+).This finding reveals that the V-O-Ti interface sites on V-based catalysts play a crucial role in NO_(x)removal under realistic conditions,providing a new perspective on NH_(3)-SCR mechanism.

关键词： NO_(x)removal Vanadia-based catalysts V-O-Ti entities Interface sites Reaction mechanism

A bHLH transcription factor,CsSPT,regulates high-temperature resistance in cucumber

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Horticultural Plant Journal 2024年第2期10卷 503-514页

作者： Yonggui Liang Chenyu yang Fangyan Ming Bingwei Yu zhihua Cheng Yixi Wang Zhengkun Qiu Xiaolan Zhang Bihao Cao Shuangshuang yan Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China) Ministry of Agriculture and Rural AffairsGuangdong Vegetable Engineering and Technology Research CenterCollege of HorticultureSouth China Agricultural UniversityGuangzhouGuangdong 510642China State Key Laboratories of Agrobiotechnology Beijing Key Laboratory of Growth and Developmental Regulation for Protected Vegetable CropsMOE Joint Laboratory for International Cooperation in Crop Molecular BreedingChina Agricultural UniversityBeijing 100193China

High-temperature stress threatens the growth and yield of crops. Basic helix-loop-helix(bHLH) transcription factors(TFs) have been shown to play important roles in regulating high-temperature resistance in plants. However, the bHLH TFs responsible for high-temperature tolerance in cucumbers have not been identified. We used transcriptome profiling to screen the high temperature-responsive candidate bHLH TFs in cucumber. Here, we found that the expression of 75 CsbHLH genes was altered under high-temperature stress. The expression of the CsSPT gene was induced by high temperatures in TT(Thermotolerant) cucumber plants. However, the Csspt mutant plants obtained by the CRISPR-Cas9 system showed severe thermosensitive symptoms, including wilted leaves with brown margins and reduced root density and cell activity.The Csspt mutant plants also exhibited elevated H_(2)O_(2) levels and down-regulated photosystem-related genes under normal conditions.Furthermore, there were high relative electrolytic leakage(REC), malondialdehyde(MDA), glutathione(GSH), and superoxide radical(O_(2)^(·-)) levels in the Csspt mutant plants, with decreased Proline content after the high-temperature treatment. Transcriptome analysis showed that the photosystem and chloroplast activities in Csspt mutant plants were extremely disrupted by the high-temperature stress compared with wildtype(WT) plants. Moreover, the plant hormone signal transduction, as well as MAPK and calcium signaling pathways were activated in Csspt mutant plants under high-temperature stress. The HSF and HSP family genes shared the same upregulated expression patterns in Csspt and WT plants under high-temperature conditions. However, most bHLH, NAC, and bZIP family genes were significantly down-regulated by heat in Csspt mutant plants. Thus, these results demonstrated that CsSPT regulated the high-temperature response by recruiting photosynthesis components, signaling pathway molecules, and transcription factors. Our results provide important insights into the heat response m

关键词： Cucumber bHLH CsSPT Photosynthesis High temperature

Mechanistic investigation on Ag-Cu_(2)O in electrocatalytic CO_(2) to CH_(4) by in situ/operando spectroscopic and theoretical analysis

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Journal of Energy Chemistry 2024年第1期88卷 521-531,I0012页

作者： Min Sun Luxiao Zhang Fuli Tian Jiaxin Li yanqiu Lei Heng Zhang Lifeng Han zhihua Guo Yonghui Gao Fenrong Liu yan Wang Luhui Wang Shanghong Zeng School of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021Inner MongoliaChina Key Laboratory of Medicinal and Edible Plants Resources of Hainan Province Hainan Vocational University of Science and TechnologyHaikou 571126HainanChina State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030Inner MongoliaChina Zhejiang Key Laboratory of Petrochemical Environmental Pollution Control Zhejiang Ocean UniversityZhoushan 316022ZhejiangChina

Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO_(2) toward CH_(4),yet a revealing insight into the reaction pathway and mechanism has remained elusive.Herein,we construct chemically bonded Ag-Cu_(2)O boundaries,in which the complete reduction of Cu_(2)O to Cu has been strongly impeded owing to the presence of surface Ag shell.The interfacial confinement effect helps to maintain Cu^(+)sites at the Ag-Cu_(2)O boundaries.Using in situ/operando spectroscopy and theoretical simulations,it is revealed that CO_(2) is enriched at the Ag-Cu_(2)O boundaries due to the enhanced physisorption and chemisorption to CO_(2),activating CO_(2) to form the stable intermediate^(*)CO.The boundaries between Ag shell and the Cu_(2)O mediate local^(*)CO coverage and promote^(*)CHO intermediate formation,consequently facilitating CO_(2)-to-CH_(4) conversion.This work not only reveals the structure-activity relationships but also offers insights into the reaction mechanism on Ag-Cu catalysts for efficient electrocatalytic CO_(2) reduction.

关键词： Ag shell Interfacial confinement effect Cu~+ Local*CO coverage CO_(2)reduction

Characterization and spatial analysis of coseismic landslides triggered by the Luding Ms 6.8 earthquake in the Xianshuihe fault zone, Southwest China

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Journal of Mountain Science 2024年第1期21卷 160-181页

作者： GUO Changbao LI Caihong yanG zhihua NI Jiawei ZHONG Ning WANG Meng yan Yiqiu SONG Deguang ZHANG yanan ZHANG Xianbing WU Ruian CAO Shichao SHAO Weiwei Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing 100081China Research Center of Neotectonism and Crustal Stability China Geological SurveyBeijing 100081China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Sichuan Institute of Geological Survey Chengdu 610081China

On September 5, 2022, a magnitude Ms 6.8 earthquake occurred along the Moxi fault in the southern part of the Xianshuihe fault zone located in the southeastern margin of the Tibetan Plateau,resulting in severe damage and substantial economic loss. In this study, we established a coseismic landslide database triggered by Luding Ms 6.8 earthquake, which includes 4794 landslides with a total area of 46.79 km^(2). The coseismic landslides primarily consisted of medium and small-sized landslides, characterized by shallow surface sliding. Some exhibited characteristics of high-position initiation resulted in the obstruction or partial obstruction of rivers, leading to the formation of dammed lakes. Our research found that the coseismic landslides were predominantly observed on slopes ranging from 30° to 50°, occurring at between 1000 m and 2500 m, with slope aspects varying from 90° to 180°. Landslides were also highly developed in granitic bodies that had experienced structural fracturing and strong-tomoderate weathering. Coseismic landslides concentrated within a 6 km range on both sides of the Xianshuihe and Daduhe fault zones. The area and number of coseismic landslides exhibited a negative correlation with the distance to fault lines, road networks, and river systems, as they were influenced by fault activity, road excavation, and river erosion. The coseismic landslides were mainly distributed in the southeastern region of the epicenter, exhibiting relatively concentrated patterns within the IX-degree zones such as Moxi Town, Wandong River basin, Detuo Town to Wanggangping Township. Our research findings provide important data on the coseismic landslides triggered by the Luding Ms 6.8 earthquake and reveal the spatial distribution patterns of these landslides. These findings can serve as important references for risk mitigation, reconstruction planning, and regional earthquake disaster research in the earthquake-affected area.

关键词： Luding earthquake Coseismic landslides Remote sensing interpretation Spatial distribution Xianshuihe fault Earthquake fault

A peak enhancement of frequency response of waveguide integrated silicon-based germanium avalanche photodetector

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Journal of Semiconductors 2024年第7期45卷 61-68页

作者： Linkai Yi Daoqun Liu Wenzheng Cheng Daimo Li Guoqi Zhou Peng Zhang Bo Tang Bin Li Wenwu Wang yan yang zhihua Li Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China

Avalanche photodetectors(APDs) featuring an avalanche multiplication region are vital for reaching high sensitivity and responsivity in optical transceivers. Waveguide-coupled Ge-on-Si separate absorption, charge, and multiplication(SACM)APDs are popular due to their straightforward fabrication process, low optical propagation loss, and high detection sensitivity in optical communications. This paper introduces a lateral SACM Ge-on-Si APD on a silicon-on-insulator(SOI) wafer, featuring a 10 μm-long, 0.5 μm-wide Ge layer at 1310 nm on a standard 8-inch silicon photonics platform. The dark current measures approximately 38.6 μA at-21 V, indicating a breakdown voltage greater than-21 V for the device. The APDs exhibit a unitgain responsivity of 0.5 A/W at-10 V. At-15 V, their responsivity reaches 2.98 and 2.91 A/W with input powers of-10 and-25 dBm, respectively. The device's 3-dB bandwidth is 15 GHz with an input power of-15 dBm and a gain is 11.68. Experimental results show a peak in impedance at high bias voltages, attributed to inductor and capacitor(LC) circuit resonance, enhancing frequency response. Furthermore, 20 Gbps eye diagrams at-21 V and-9 dBm input power reveal signal to noise ratio(SNRs) of 5.30. This lateral SACM APD, compatible with the stand complementary metal oxide semiconductor(CMOS) process,shows that utilizing the peaking effect at low optical power increases bandwidth.

关键词： photodetectors optical communications responsivity 3-dB bandwidth

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习近平关于制造强国重要论述的核心要义

理论视野 2024年第4期290卷 25-31页

作者：汤志华李延广西师范大学广西师范大学马克思主义学院

习近平关于制造强国重要论述从“两个大局”战略高度,在深刻把握以中国式现代化全面推进民族伟大复兴的内在要求、明确新时代我国制造强国建设重点任务基础上,强调以新质生产力推动高质量发展进而实现制造强国目标,深刻回答了“为什么... 详细信息

习近平关于制造强国重要论述从“两个大局”战略高度,在深刻把握以中国式现代化全面推进民族伟大复兴的内在要求、明确新时代我国制造强国建设重点任务基础上,强调以新质生产力推动高质量发展进而实现制造强国目标,深刻回答了“为什么要建设制造强国”“建设什么样的制造强国”“怎样建设制造强国”系列重大问题。深入学习和准确把握其中的核心要义对加快我国制造强国建设具有重大意义。

关键词：习近平制造强国高质量发展新质生产力