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Chemical Research in Chinese Universities 1999年第3期15卷 218-225页

作者： WU Jie-ying TIAN Yu-peng XIE Fu-xin ni shi-sheng Department of Chemistry Anhui UniversityHefei 230039P.R.China

The syntheses and characterization of novel biferrocene trinuclear complexes of Schiff base ligand, S methyl N (ferrocenyl 1 methyl methylidene)dithiocarbazate [hereafter abbreviated as HL (1)], are described. The X ray diffraction studies have established the structures of PdL 2 (3) and CuL 2 (4). The geometry of Pd(Ⅱ) in (3) is close to a square plane and in the novel cis configuration the two ferrocene moieties are in cis configuration, while that of Cu(Ⅱ) in (4) is close to a tetrahedral configuration. The electrochemical measurements suggested that the square planar configuration of ni(Ⅱ) and Pd(Ⅱ) moieties can effectively transmit the redox effects of the ferrocene moieties, while the tetrahedral configuration of the Cu(Ⅱ) complex can not transmit the redox effects. The degenerate four wave mixing (DFWM) measurements showed that the complexes exhibit obviously nonlinear optical (NLO) response. The magnitude of their third order NLO susceptibility can be explained by their structure and electrochemical properties.

关键词： Electrochemistry cis Configuration biferrocene Third order nonlinear optical property

Improving IEC thermal model for oil natural air natural transformers using optimised parameters based on dynamic simulation

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High Voltage 2024年第1期9卷 217-229页

作者： Lijing Zhang Yingting Luo Gehao sheng Zizhan ni Xiuchen Jiang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Electric Power Research Institute of Guangdong Power Grid Corporation GuangzhouChina

Accurate assessment of hot-spot temperature is essential for the safe operation of power *** dynamic thermal models cannot estimate hot-spot temperature accurately since some input parameters are roughly determined by transformer capacity and cooling mode while ignoring the effect of winding structure,tank dimensions,and material physical *** improve the accuracy of temperature assessment,empirical parameters of the IEC thermal model including thermal constants,winding and oil exponents are optimised with the help of numerical simulation in this *** on energy conservation and heat transfer theory,a computational fluid dynamic(CFD)model of a transformer in oil natural air natural(ONAN)cooling mode is *** CFD model simulates the entity's structure,sizes,and multi-stage heat dissipation processes realistically,so it can more precisely calculate the dynamic hot-spot *** to the simulated temperature curves at different operating conditions,the thermal constants and oil exponent are estimated using non-linear regression,and the winding exponent is optimised using linear regression.A case study is conducted on an ONAN *** shows the improved IEC model with optimised parameters can more accurately evaluate hot-spot temperature,and the absolute error is decreased by 2.4 K(38.7%)compared with traditional thermal models.

关键词： temperature properties. thermal

A Knowledge-enhanced Two-stage Generative Framework for Medical Dialogue Information Extraction

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Machine Intelligence Research 2024年第1期21卷 153-168页

作者： Zefa Hu Ziyi ni Jing shi Shuang Xu Bo Xu School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper focuses on term-status pair extraction from medical dialogues(MD-TSPE),which is essential in diagnosis dia-logue systems and the automatic scribe of electronic medical records(EMRs).In the past few years,works on MD-TSPE have attracted increasing research attention,especially after the remarkable progress made by generative ***,these generative methods output a whole sequence consisting of term-status pairs in one stage and ignore integrating prior knowledge,which demands a deeper un-derstanding to model the relationship between terms and infer the status of each *** paper presents a knowledge-enhanced two-stage generative framework(KTGF)to address the above *** task-specific prompts,we employ a single model to com-plete the MD-TSPE through two phases in a unified generative form:We generate all terms the first and then generate the status of each generated *** this way,the relationship between terms can be learned more effectively from the sequence containing only terms in the first phase,and our designed knowledge-enhanced prompt in the second phase can leverage the category and status candidates of the generated term for status ***,our proposed special status"not mentioned"makes more terms available and en-riches the training data in the second phase,which is critical in the low-resource *** experiments on the Chunyu and CMDD datasets show that the proposed method achieves superior results compared to the state-of-the-art models in the full training and low-re-sourcesettings.

关键词： Medical dialogue understanding information extraction text generation knowledge-enhanced prompt low-resource setting dataaugmentation

Maps Preserving Semi-Fredholm Operators with Fixed Nullity

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Journal of Mathematical Research with Applications 2024年第4期44卷 533-540页

作者： Mengran ni Weijuan shi Department of Mathematics Shaanxi Normal University

Let X be an infinite-dimensional complex Banach space, and B(X) the algebra of all bounded linear operators on X. Given an integer n ≥ 1, we characterize all the bijective maps on B(X) preserving the difference of se... 详细信息

关键词： operator algebra adjacency preserver map semi-Fredholm operator

双四氮杂大环镍(Ⅱ)配合物催化的化学振荡反应

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无机化学学报 2000年第1期16卷 136-138页

作者：李村谢复新倪诗圣南京大学配位化学国家重点实验室南京210008 安徽大学化学系合肥230039

New oscillating reactions catalyzed by a bistetraazacrocyclic nickel (Ⅱ) complex ni2L(ClO4), where L is bis(11,13 dimethyl 1,4,7,10 tetraza 10,13 cyclotridecadien 12 ylidene), in acidic bromate medium have been studied. We obtained the concentration ranges of main reactant within which the oscillations were observed in the system. We discussed the influence of temperature, Vc ,Br-, Ag+, Hg2+, acetonitrile or acrylamide on the oscillations. The results indicated that Br-played an important role in the control reaction progress and free radical might be involved in the reaction process. We recorded the oscillation trajectories of this system. It was different from classical BZ reaction and some other tetraazamacrocyclic complexes catalyzed system.

关键词：镍(Ⅱ)配合物化学荡反应双四氮杂大环

四氮杂大环四烯镍(Ⅱ)配合物催化的化学振荡反应

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无机化学学报 2000年第5期16卷 847-851页

作者：李村谢复新倪诗圣安徽大学化学系合肥230039

It is reported in this paper that a tetraazamacrocyclic nickel complex niL(CIO4,)2, where L is 2, 4, 4, 9, 11, 11-hexamethyl-1, 5, 8, 12 -tetraazacyclotetradeca- 1, 5, 8, 12- tetraene, can serve as oscillating catalyst in the system of NaBrO3-Pyr-H2SO4. The ranges of initial concentration of main reactants in the system were obtained. The influence of temperature, Vc, Br-, Ag+, Hg2+, acetonitrile or acrylamide on the oscillations were discussed. The results indicated that Br- played an important role controlling reaction progress and some free ***2 may be involved in the reaction process. The stirring rate can affect oscillating reactions. The oscillation trajectories of this system were recorded. They are different from classical BZ reactions and some other tetraazamacrocyclic complexes catalyzed systems. The mechanism is briefly discussed.

关键词：四氮杂大环镍配合物化学振荡反应丙酮酸

Growth kinetics of titanium carbide coating by molten salt synthesis process on graphite sheet surface

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1858-1864页

作者： Xiaoyu shi Chongxiao Guo Jiamiao ni Songsong Yao Liqiang Wang Yue Liu Tongxiang Fan State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The synthesis of carbide coatings on graphite substrates using molten salt synthesis(MSS),has garnered significant interest due to its cost-effective *** study investigates the reaction process and growth kinetics involved in MSS,shedding light on key aspects of the *** involvement of Ti powder through liquid-phase mass transfer is revealed,where the diffusion distance and quantity of Ti powder play a crucial role in determining the reaction rate by influencing the C content gradient on both sides of the ***,the growth kinetics of the carbide coating are predominantly governed by the diffusion behavior of C within the carbide layer,rather than the chemical reaction *** analyze the kinetics,the thickness of the carbide layer is measured with respect to heat treatment time and temperature,unveiling a parabolic relationship within the temperature range of 700-1300℃.The estimated activation energy for the reaction is determined to be 179283 J·mol^(-1).These findings offer valuable insights into the synthesis of carbide coatings via MSS,facilitating their optimization and enhancing our understanding of their growth mechanisms and properties for various applications.

关键词： titanium carbide graphite molten salt kinetic analysis

CAGCN:Centrality-Aware Graph Convolution Network for Anomaly Detection in Industrial Control Systems

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Journal of Computer Science & Technology 2024年第4期39卷 967-983页

作者： Jun Yang Yi-Qiang sheng Jin-Lin Wang Hong ni National Network New Media Engineering Research Center Institute of AcousticsChinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

In industrial control systems,the utilization of deep learning based methods achieves improvements for anomaly ***,most current methods ignore the association of inner components in industrial control *** industrial control systems,an anomaly component may affect the neighboring components;therefore,the connective relationship can help us to detect anomalies *** this paper,we propose a centrality-aware graph convolution network(CAGCN)for anomaly detection in industrial control *** the traditional graph convolution network(GCN)model,we utilize the concept of centrality to enhance the ability of graph convolution networks to deal with the inner relationship in industrial control *** experiments show that compared with GCN,our CAGCN has a better ability to utilize this relationship between components in industrial control *** performances of the model are evaluated on the Secure Water Treatment(SWaT)dataset and the Water Distribution(WADI)dataset,the two most common industrial control systems datasets in the field of industrial anomaly *** experimental results show that our CAGCN achieves better results on precision,recall,and F1 score than the state-of-the-art methods.

关键词： graph convolution network(GCN) data mining network centrality anomaly detection industrial control system

Pangenome and multi-tissue gene atlas provide new insights into the domestication and highland adaptation of yaks

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Journal of Animal Science and Biotechnology 2024年第5期15卷 1832-1850页

作者： Daoliang Lan Wei Fu Wenhui Ji Tserang‑Donko Mipam Xianrong Xiong shi Ying Yan Xiong Peng sheng Jiangping ni Lijun Bai Tongling Shan Xiangdong Kong Jian Li Ministry of Education of Key Laboratory of Qinghai‑Tibetan Plateau Animal Genetic Resource and Utilization Southwest Minzu UniversityChengduChina College of Animal&Veterinary Sciences Southwest Minzu UniversityChengduChina Institute of Qinghai‑Tibetan Plateau Southwest Minzu UniversityChengduChina Jiguang Gene Biotechnology Co. Ltd.NanjingChina Chengdu Genepre Technology Co. Ltd.ChengduChina Shanghai Veterinary Research Institute Chinese Academy of Agricultural SciencesShanghaiChina

Background The genetic diversity of yak,a key domestic animal on the Qinghai-Tibetan Plateau(QTP),is a vital resource for domestication and breeding *** study presents the first yak pangenome obtained through the de novo assembly of 16 yak *** We discovered 290 Mb of nonreference sequences and 504 new *** pangenome-wide presence and absence variation(PAV)analysis revealed 5,120 PAV-related genes,highlighting a wide range of variety-specific genes and genes with varying frequencies across yak *** component analysis(PCA)based on binary gene PAV data classified yaks into three new groups:wild,domestic,and ***,we pro-posed a‘two-haplotype genomic hybridization model'for understanding the hybridization patterns among breeds by integrating gene frequency,heterozygosity,and gene PAV data.A gene PAV-GWAS identified a novel gene(Bos-Gru3G009179)that may be associated with the multirib trait in Jinchuan ***,an integrated transcrip-tome and pangenome analysis highlighted the significant differences in the expression of core genes and the muta-tional burden of differentially expressed genes between yaks from high and low *** analysis across multiple species revealed that yaks have the most unique differentially expressed m RNAs and lnc RNAs(between high-and low-altitude regions),especially in the heart and lungs,when comparing high-and low-altitude *** The yak pangenome offers a comprehensive resource and new insights for functional genomic studies,supporting future biological research and breeding strategies.

关键词： High-and low-altitude Novel genes Pangenome PAV-GWAS Yak

Effects of rafting on the meso deformation and fracture behaviour of a ni-based single crystal superalloy at room temperature: In-situ observation and simulation

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Science China(Technological Sciences) 2024年第7期67卷 2133-2146页

作者： TAN Long YANG XiaoGuang shi DuoQi FAN Yongsheng shi Yi School of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 102206China School of Materials Science&Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Microstructural rafting of ni-based single-crystal(SC) superalloys is inevitable at elevated temperatures during long-term service with mechanical loading, which significantly affects the mechanical behaviour of the material. In this study, the effects of rafting on the mesodeformation and fracture behaviour of a ni-based SC superalloy under cyclic and tensile loads were investigated using in situ scanning electron microscopy(SEM), digital image correlation(DIC), and crystal plasticity finite element method(CP-FEM) simulations. The results indicated that the tensile strength decreased significantly in the rafted specimens. In the cyclic tests, both the virgin and rafted specimens showed an increase in the maximum shear strain with cycle number. The interaction of cross-slip bands was captured by in situ SEM-DIC around the micro-notch of the virgin specimens during the tensile test, while a more homogeneous local deformation field was observed in the rafting specimens. In addition,the fracture behaviour was strongly influenced by the rafting morphology. The crack exhibited instantaneous and long-range fracture features along the octahedral plane as it propagated in the rafting specimen, whereas it deflected over a short distance between the crystallographic planes at an early stage in the virgin specimen, which is consistent with the CP-FEM ***, the CP-FEM results for the crack initiation direction on(111) dominant slip plane were consistent with the in situ SEM observations.

关键词： in-situ SEM-DIC ni-based SC superalloys microstructural rafting deformation crack path CP-FEM