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乙酰丙酮铱Ir(acac)_(3)电子结构及光学性质的理论研究

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原子与分子物理学报 2025年第1期42卷 1-7页

作者：樊依佳蔚娇娇郭家成陈扬尹杜恭贺西北工业大学伦敦玛丽女王大学工程学院西安710129 西安邮电大学理学院西安710121

乙酰丙酮铱是一种由过渡金属Ir与乙酰丙酮酸(acetylcaetonato)有机部分组成的过渡金属有机配合物,它是一种重要的绿光磷光材料,同时其也是多种铱系发光材料的组成部分.采用密度泛函理论(DFT)对Ir(acac)_(3)单体及其二聚物的基态几何结... 详细信息

乙酰丙酮铱是一种由过渡金属Ir与乙酰丙酮酸(acetylcaetonato)有机部分组成的过渡金属有机配合物,它是一种重要的绿光磷光材料,同时其也是多种铱系发光材料的组成部分.采用密度泛函理论(DFT)对Ir(acac)_(3)单体及其二聚物的基态几何结构进行了优化,在此基础上考察了它们的振动和红外光谱,并使用CIS方法对它们的激发态性质进行了理论研究.计算得到的单体和二聚物的吸收光谱均在紫外波段,单体的主要吸收峰有260 nm,350 nm,414 nm,二聚物的主要吸收峰有299 nm,353 nm,401 nm.计算得到了二者在乙腈CH_(3)CN溶液中的吸收光谱,与它们气相情况的结果相比,溶剂极性的影响使得电子吸收谱发生蓝移.计算结果表明Horst Kunkely和Arnd Vogler所得光谱中既含有单体的特征光谱,又含有二聚体的特征光谱,证明实验溶液中同时存在乙酰丙酮铱的低聚物,并且二者的组分比能被合理推算.最后,对多聚体的形成机理作了简单讨论.

关键词： Ir(acac)_(3) 密度泛函理论(DFT) CIS 电子吸收光谱溶液效应

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Basic Research on Key Techniques Related to Urban 3D Pipe Network Modeling

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Geo-Spatial Information Science 2002年第4期5卷 41-45页

作者： du Guoming gong Jianya XIONG Hanjiang National Laboratory for Information Engineering in Surveying Mspping and Remote Sensing WTUSM

A new geometric modeling approach is introduced in this *** the principle of modeling of 3D pipe network is discussed in *** the procedures of implementing pipe network visualization and system functions are ***,several efficient methods for speeding up display of graphics are *** new geometric modeling approach offers to people a new way to solve 3D visualization of complex urban pipe network.

关键词： D pipe network visualization modeling

Multi-Layer Synthesis of HighlyStructured Texture

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Wuhan University Journal of Natural Sciences 2012年第4期17卷 302-308页

作者： TANG Li YU Rongwei GU Yuanting YUAN Jie du gong School of Computer Science and Engineering ChangshuInstitute of Technology Changshu 215500 Jiangsu China State Key Laboratary of Software Engineering WuhanUniversity Wuhan 430072 Hubei China Key Laboratory of Aerospace Information Security andTrust Computing Ministry of Education Wuhan 430072 HubeiChina Institute of Software Chinese Academy of Sciences Beijing100080 Beijing China

In this paper, a novel concept of multilayer synthesis and a general framework for texture synthesis method are presented. Within this framework, we first decompose the texture into the supposed pattern layer and material layer in the frequency domain by an E-texton extracting algorithm, then manipulate and extend them respectively according to their own personalities, and finally merge the newly synthesized pattern layer and material layer again to generate the final output. Experiment results show that our method not only greatly improves the synthesis quality for those cases that single-layer synthesis cannot handle well but also provides an ability of achieving various special synthesis effects.

关键词： texture synthesis texture layer multilayer synthesis

Distribution of soil carbon in different grassland types of the Qinghai-Tibetan Plateau

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Journal of Mountain Science 2016年第10期13卷 1806-1817页

作者： LIU Shu-li du Yan-gong ZHANG Fa-wei LIN Li LI Yi-kang GUO Xiao-wei LI Qian CAO Guang-min Northwest Institute of Plateau Biology Chinese Academy of SciencesQinghai 810001China University of Chinese Academy of Sciences Beijing 100049China

Accurate estimate of soil carbon storage is essential to reveal the role of soil in global carbon cycle. However, there is large uncertainty on the estimation of soil organic carbon(SOC) storage in grassland among previous studies, and the study on soil inorganic carbon(SIC) is still lack. We surveyed 153 sites during plant peak growing season and estimated SOC and SIC for temperate desert, temperate steppe, alpine steppe, steppe meadow, alpine meadow and swamp, which covered main grassland in the Qinghai Plateau during 2011 to 2012. The results showed that the vertical and spatial distributions of SOC and SIC varied by grassland types. The SOC amount mainly decreased from southeast to northwest, whereas the SIC amount increased from southeast to northwest. The magnitude of SOC amount in the top 50 cm across grassland types ranked by: swamp > alpine meadow >steppe meadow > temperate steppe > alpine steppe > temperate desert, while the SIC amount showed an opposite order. There was a great deal of variation in proportion of SOC and SIC among different grassland types(from 55.17 to 94.59 for SOC and 5.14 to 44.83 for SIC). The total SOC and SIC storage was 5.78 Pg and 1.37 Pg, respectively, in the top 50 cm of soil in Qinghai Province. The mixed linear model revealed that grassland types was the predominant factor in spatial variations of SOC amount while grassland types and soil p H accounted for those of SIC amount. Our results suggested that the community shift of alpine meadow towards alpine grassland induced by climate warming would decrease carbon sequestration capacity by 6.0 kg C m2.

关键词： Soil organic carbon Soil inorganic carbon Different grassland types Carbon distribution Storage

Alterations to biological soil crusts with alpine meadow retrogressive succession affect seeds germination of three plant species

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Journal of Mountain Science 2016年第11期13卷 1995-2005页

作者： LI Yi-kang OUYANG Jing-zheng LIN Li XU Xing-liang ZHANG Fa-wei du Yan-gong LIU Shu-li CAO Guang-min HAN Fa Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001China University of Chinese Academy of Sciences Beijing 100049China Institute of Geographic Sciences&Natural Resources Research the Chinese Academy of SciencesBeijing 100101China Liancheng National Nature Reserve of Gansu Province Yongdeng Country 730000China

Biological soil crusts(BSCs) are the important components of alpine meadow *** extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing *** is significant interest in impacts of crust composition on plant seed germination,especial l y in(semi-) arid ***,little is known about the influences of BSCs,and their associations with alpine meadow succession,on germination of typical alpine meadow vascular plant *** a full factorial common-gardenexperiment,we studied effects of:(1) crust type,(2) seed position,and(3) surface texture on seed *** chose three typical alpine meadow plant species(*** pratensis,Tibetia himalaica and Potentillen nivea),which belonged to different functional groups(graminoids,legumes,and forbs) and play important roles in all alpine meadow succession *** type and seed position influenced seed germination,and the inhibitory effects of BSCs depended on the crust type and seed species *** major factors influencing seed germination were BSC type,seed position,soil texture,and the interactions between BSC type and seed position; species and seed position; species andsurface texture; and species,crust type,and surface *** crust significantly inhibited germination of all *** position also had a significant effect on seed germination(p during seed germination,depending on the BSC succession *** their influences on seed germination,BSCs can strongly

关键词： Crust type Seed position Microenvironment Germination Tibetan Plateau Vascular plants

Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model

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Computers, Materials & Continua 2025年第1期82卷 843-862页

作者： Feifei Yu Yongxian Huang Guoyan Chen Xiaoqing Yang Canyi du Yongkang gong School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China School of Automotive and Transportation Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China

To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precisely pinpointing misfire *** the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different *** collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,*** collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two *** results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENET model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-Term Memory(LSTM),Transformer,and Multi-Scale Residual Networks(MSRESNET),yielding accuracy rates of 84%,79%,and 95%,*** underscores the superior accuracy of the SENET model in detecting engine misfire faults compared to other ***,the F1 scores for each type of recognition in the SENET model surpassed 0.98,outperforming the baseline *** analysis indicated that the misclassified samples in the LSTM and Transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire *** delve deeper,we conducted a visual analysis of the features extracted by the LSTM and SENET models using T-distributed Stochastic Neighbor Embedding(T-SNE)*** findings revealed that,in the LSTMmodel,data points of the same type tended to cluster together with significant ***,in the SENET model,data points of various types were more widely and evenly dispersed,demonstra

关键词： Channel attention SENET model engine misfire fault fault detection

Silurian Seismites in Hanxia,Yumen,North Qilian Mountains,and Their Tectonic Significance

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 385-390页

作者： du Yuansheng, gong Shuyun, HAN Xin, WANG Jiasheng, GU Songzhuand LIN Wenjiao Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, Hubei Faculty of Earth Sciences China University of Geosciences Wuhan 430074 Hubei [?]2du Yuansheng Male born in 1958 graduated from Wuhan College of Geology and obtained his Master's degree in 1989 and Ph. D degree in 1994. He is now a professor of China University of Geosciences and engaged in sedimentology stratigraphy and geology of orogenic belts. Tel: (027) 87436249 Fax: (027) 87436247 E-mail: dxyyz@***

The Caledonian orogenic belt of the North Qilian Mountains is an intensely active structure belt. In the process of the Late Caledonian syn-orogeny, the North Qilian-Hexi Corridor area was situated on the tectonic background of a syn-orogenic basin. In response to the orogenic process of the North Qilian Mountains, typical earthquake event deposits—seismites of the Silurian were widely distributed around Hanxia of Yumen City, the Liyuan River of Sunan County and Biandukou of Minle County. In the Hanxia area, where seismites are typically developed, clastic deposits of tidal-flat facies are the background deposits of the Hanxia Formation. The earthquake event deposits are characterized by sandy mudstone veins, synsedimentary microfractures, micro-corrugated laminations and earthquake breccias, which in turn constitute complex seismites, featuring seismic corrugation, shattering and liquefied sandy mudstone veins, auto-clastic breccias and intraclastic parabreccias. The seismites and tidal flat deposits formed typical sequences of earthquake event deposits.

关键词： Gansu Province North Qilian orogenic belt Caledonian Stage Silurian seismites earthquake event deposits

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高效的周期性移动定位优化策略

北京邮电大学学报 2017年第6期40卷 80-85页

作者：杜惠英杜武恭北京信息科技大学信息管理学院北京100192 中国广播电视网络有限公司北京100045

针对周期性监控应用普遍存在因定位策略局限而导致移动终端耗电量大、精度低等诸多问题,从博弈论和计量经济学角度构建了高效的定位优化策略模型,根据用户使用场景,分析历史移动定位数据,充分考虑各种网络定位和终端定位的基础定位方式... 详细信息

针对周期性监控应用普遍存在因定位策略局限而导致移动终端耗电量大、精度低等诸多问题,从博弈论和计量经济学角度构建了高效的定位优化策略模型,根据用户使用场景,分析历史移动定位数据,充分考虑各种网络定位和终端定位的基础定位方式及其成功率,构建依次选用全球定位系统、基于位置业务开发的定位技术、无线宽带、基站等的动态移动定位策略.Matlab仿真结果表明,周期性移动定位策略能提高首次定位速度,并能快速精准地进行下一次移动定位,进而可降低通信网络和移动终端系统的压力.

关键词：移动定位定位监控定位策略基于位置的服务

The crystal and molecular structure of tetrahydro-thiazole-2-thione

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Chinese Journal of Chemistry 1984年第2期2卷 105-110页

作者： XU Xiao-Jie ZHOU gong-du HAN Yu-Zhen Institute of Physical Chemistry,Peking UniversityLI Chong-Xi Department of Chemistry,Peking University Institute of Physical Chemistry Peking University Department of Chemistry Peking University

The crystal of tetrahydrothiazole—2-thione（TTT）belongs to monoclinic *** P2/*** are eight molecules in an unit cell with parameters a=13.844（7）,b=5.614（2）,c=13.516（7）,β=95.08（5）°,V=1046.3 （9）.The three dimensional intensity datawere obtained on a Syntex R3 four-circle diffractometer,and the number of the independent diffrac-tions amounted to *** structure was solved by direct method and refined by block-diagonal least-squares *** final R is *** crystal,the molecular structure is between 1 and 2 in which S（1）,S（2）,Nand C（1）are coplanar with *** use CNDO/2 programmes written by ourselves on Eclipse computer to compute the electronicenergies,molecular total energies,dipole moments,the charge densities and net charges of each atomof TTT and its N-benzoylated *** color of the acylated TTT and its properties for aminolysis are discussed.

关键词： The crystal and molecular structure of tetrahydro-thiazole-2-thione