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Chinese Journal of Structural Chemistry 2021年第10期40卷 1309-1316页

作者： yan Zhen-Shuo kang yan-hui CHEN yang-Ling HUO Li-Ni Guangxi University of Chinese Medicine Nanning 530001China Hebei University of Engineering Handan 056038China

A highly selective iron ions fluorescent probe based on the benz(c)acridine-1,2,3-triazole derivatives was produced by multi-step reactions. 1-(7-Benz[c]acridinyl)-4-(4-methylphenyl)-1,2,3-triazole(4 a), C_(26)H_(18)N_(4), was structurally determined by single-crystal X-ray diffraction. It crystallizes in the trigonal system, space group R-3 with a = 36.230(10), b = 36.230(10), c = 7.993(3)Å, β = 90°, V = 9086(6)Å^(3), Z = 18, D_(c)= 1.271 g/cm^(3), F(000) = 3636, μ = 0.602 mm^(-1), the final R = 0.0865 and wR = 0.1619 for 3951 observed reflections(I > 2σ(I)). X-ray analysis indicated that all four rings of benz(c)acridine are in the same plane, and the 1,2,3-triazole ring and the corresponding linked benzene(C(1)–C(6)–C(7)–C(8)–C(9)–N(1)) are approximately perpendicular with a dihedral angle of 106.5°. The crystal packing of the compound was stabilized by two weak interactions between C(11)–H(10)…N(4) and C(18)–H(18)…N(1). In fluorescence spectra studies, compound 4 c was exhibited good selectivity and sensitivity towards iron ions in DMSO: mops buffer solution. Furthermore, 4 c was successfully used for imaging iron ions in living He La cervical cancer cells.

关键词： benz(c)acridine-1 2 3-triazole crystal structure fluorescent probe iron ions

Improved modified moving average analysis of T-wave alternans using least squares-based curve fitting method

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International Journal of Biomathematics 2014年第4期7卷 173-183页

作者： Xiang-Kui Wan kang-hui yan Ang Li Ming-Hu Wu School of Electrical and Electronic Engineering Hubei University of Technology Wuhan 430068 P. R. China School of Information Engineering Guangdong University of Technology Guangzhou 510006 P. R. China School of Electrical and Electronic Engineering Hubei University of Technology Wuhan 430068 P. R. China

T-wave alternans （TWA） in surface electrocardiograph （ECG） signal is considered a marker of abnormal ventricular function which may be associated with ventricular tachy- cardia. Several methods have been developed in recent years to evaluate the important feature. One such method is known as modified moving average （MMA） analysis, which performs well for different levels of TWA, but it is sensitive to the noise in T-waves. In this paper we propose an improved MMA algorithm, which adds a stage of T-wave curve fitting for the MMA method before intermediate averaging. The curve fitting is performed by means of least square method technique. Our assessment study demon- strates the improved performance.

关键词： Electrocardiograph T-wave alternans modified moving average least squaresmethod curve fitting.

Influence of powder oxidation on powder properties and formability in H13 hot-work steels processed by electron beam melting

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Journal of Iron and Steel Research International 2024年第4期31卷 924-932页

作者： Wei Liu yan Wang Li-xiong Han Ying-kang Wei hui-ping Tang Shi-feng Liu School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Engineering Zhejiang University City CollegeHangzhou 310015ZhejiangChina

The oxygen content of metal powder is decisive for the recyclability of *** research on the effect of oxygen content on powder properties and material formability has practical significance for economical production with additive manufacturing while preventing the waste of ***,we deliberately oxidized the powder by baking at high temperature to increase the oxygen content in the powder and gave the calculation method of the oxygen content in the powder oxidation *** majority of oxygen element was found in the oxide particles in the powder and the oxide flm on the powder surface,which did affect the flowability of the *** is worth noting that the increase in the oxygen content does not change the phase of H13 steel,but it can promote the molten pool flow and obtain a smoother *** increase in the oxygen content in the powder is not the decisive factor for the formability and defects of the printed *** is the combined effect of the powder deformation,the increase in the oxygen content,and the impurity pollution after repeated use,which leads to the limitation of repeated utilization of the powder.

关键词： Additive manufacturing Electron beam melting H13 steel powder-Powder oxidation

Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature

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Chinese Journal of Aeronautics 2024年第2期37卷 541-556页

作者： Rui ZHAO Yueshuai SONG hui kang Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its *** achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution *** evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension *** findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing *** effects of grain size,such as pinning and splitting,are amplified at higher brazing ***,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture *** fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack ***,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures.

关键词： EYWORDS Ultra-thin-walled structure Brazing Inconel 718 Grain size effect Brazing temperature

Effects of pinholes on zerooffset of single-axis normal-tracking measurement system

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Journal of Measurement Science and Instrumentation 2016年第4期7卷 336-341页

作者： LI Huai-lu WANG Zhong kang yan-hui FU Lu-hua State Key Laboratory of Precision Measuring Technology and Instrument Tianjin University Tianjin 300072 China Division of Metrology in Length and Precision Engineering National Institute of Metrology Beijing W0029 China

A single-axis normal-tracking measurement system is proposed, which can solve the problem of measuring large curved surface. According to Collins formula, the tilt dependent error of the measurement system is studied, which uses Gaussian beam as the light source. By theoretical analysis and numerical simulation, the influence of the error is presented. The results show that there is the difference between point source and Gaussian beam for differential confocal microscopy. The opti-mal diameter of pinhole can be determined by the mathematical model and the actual parameters of the measurement system. The optimal pinhole diameter of this measurement system is 20 to 35 pm for 633 nm wavelength light source.

关键词： differential confocal microscopy Gaussian beam Collins formula pinhole optimum

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圆锥量规锥度的高精度光学干涉法测量

光学精密工程 2011年第11期19卷 2551-2557页

作者：康岩辉张恒中国计量科学研究院北京100013

针对超精密数控机床对圆锥量规锥度高精度测量的需求,研究了一种将"大数"和"小数"相结合,准确测量圆锥量规锥度的方法。介绍了锥度测量系统的基本原理及组成,给出了实验测量结果,分析了测量系统的不确定度。该测量方法利用最大分度间隔... 详细信息

针对超精密数控机床对圆锥量规锥度高精度测量的需求,研究了一种将"大数"和"小数"相结合,准确测量圆锥量规锥度的方法。介绍了锥度测量系统的基本原理及组成,给出了实验测量结果,分析了测量系统的不确定度。该测量方法利用最大分度间隔误差为0.10″的多齿分度台构成高准确度分度系统保证测量"大数"部分的准确性,采用激光偏振干涉装置及精密回转工作台组成小角度测量系统保证测量"小数"部分的精度,而双光束白光干涉系统实现了测量位置的精确定位。实验和分析结果表明,该方法在不确定度置信因子k为2时,锥度测量系统的扩展不确定度约为0.24″,优于0.3″,可实现圆锥量规任意锥度的高精度测量。

关键词：光学干涉法圆锥量规锥度测量

Robust Interval State Estimation for Distribution Systems Considering Pseudo-measurement Interval Prediction

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 179-188页

作者： Xu Zhang Wei yan Meiqing Huo hui Li the School of Electrical Engineering Chongqing UniversityChongqing 400044China

Interval state estimation(ISE)can estimate state intervals of power systems according to confidence intervals of predicted pseudo-measurements,thereby analyzing the impact of uncertain pseudo-measurements on ***,predicted pseudo-measurements have prediction errors,and their confidence intervals do not necessarily contain the truth values,leading to estimation biases of the *** solve this problem,this paper proposes a pseudo-measurement interval prediction framework based on the Gaussian process regression(GPR)model,thereby improving the prediction accuracy of pseudo-measurement confidence ***,a weight assignment strategy for improving the robustness of weighted least squares(WLS)ISE is *** strategy quantifies the deviation between the pseudo-measurement intervals and their estimated intervals and assigns smaller weights to the pseudo-measurement intervals with larger deviations,thereby improving the estimation accuracy and robustness of the *** paper adopts the data from the supervisory control and data acquisition(SCADA)system of the New York Independent System Operator(NYISO).It verifies the advantages of the GPR method for pseudo-measurement interval prediction by comparing it with the quantile regression and neural network *** addition,this paper demonstrates the effectiveness of the proposed weight assignment strategy through the IEEE 14-bus ***,the differences in the estimation accuracy and the bad data identification between the robust interval state estimation and deterministic state estimation are discussed.

关键词： Interval state estimation interval analysis pseudo-measurement Gaussian process regression(GPR)

Recent progresses in thermal treatment of β-Ga_(2)O_(3) single crystals and devices

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1659-1677页

作者： Yuchao yan Zhu Jin hui Zhang Deren yang State Key Laboratory of Silicon and Advanced Semiconductor Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices ZJU-Hangzhou Global Scientific and Technological Innovation CenterHangzhou 311200China

In recent years,ultra-wide bandgap β-Ga_(2)O_(3) has emerged as a fascinating semiconductor material due to its great potential in power and photoelectric *** semiconductor industrial,thermal treatment has been widely utilized as a convenient and effective approach for substrate property modulation and device ***,a thorough summary of β-Ga_(2)O_(3) substrates and devices behaviors after high-temperature treatment should be *** this review,we present the recent advances in modulating properties of β-Ga_(2)O_(3) substrates by thermal treatment,which include three major applications:(ⅰ)tuning surface electrical properties,(ⅱ)modifying surface morphology,and(ⅲ)oxidating ***,regulating electrical contacts and handling with radiation damage and ion implantation have also been discussed in device *** each category,universal annealing conditions were speculated to figure out the corresponding problems,and some unsolved questions were proposed *** review could construct a systematic thermal treatment strategy for various purposes and applications of β-Ga_(2)O_(3).

关键词： β-gallium oxide thermal treatment substrates devices

Effect of heat treatment on microstructural evolution,mechanical properties and tribological properties of H13 steel prepared using selective laser melting

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Journal of Iron and Steel Research International 2024年第5期31卷 1246-1259页

作者： Li-xiong Han yan Wang Shi-feng Liu Zhao-hui Zhang Wei Liu Xin yang Dang-shen Ma Jian Zhou Ying-kang Wei College of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina Zhejiang University City College Hangzhou310015ZhejiangChina China Iron and Steel Research Institute Group Co. Ltd.Beijing100081China

H13 tool steel was successfully prepared by selective laser melting(SLM)*** effects of heat treatment on the microstructure,mechanical properties,and tribological properties of SLMed H13 steel were *** heat treatment process involved a solution treatment and a double aging treatment of the deposited H13 tool steel prepared by *** aim is to optimize the microstructure and mechanical properties of SLMed H13 *** to the rapid heating and cooling effects of SLM,carbide precipitation in the deposited H13 steel was not uniform and residual stresses were *** purpose of the solution treatment is to dissolve the solution at a high temperature to eliminate the residual stresses and defects introduced by the SLM-forming *** solution treatment and first aging treatment produced the precipitation of small carbides at the grain boundaries and inside the crystals,which increased the hardness of SLMed H13 *** hardness increased from 538±4.0 HV of the as-deposited sample to 548±5.8 HV of samples after the first aging ***,the ultimate tensile strength and the elongation at break decreased from 1882 MPa and 11.5%in the as-deposited sample to 1697 MPa and 7.9%in those after the first aging treatment,***,the friction coefficient and wear rate in the as-deposited sample decreased from 0.5160 and 2.36×10^(–6)mm^(−3)N^(−1)m^(−1)to 0.4244 and 1.04×10^(–6)mm^(−3)N^(−1)m^(−1),***,the distribution of carbides inside the crystals was not *** second aging treatment adjusted the morphology of carbide precipitation and made it more uniform,but the precipitation of carbides grew and settled at the bottom of the grain *** hardness decreased to 533±6.7 HV compared with that with the first aging treatment,but the ultimate tensile strength and plasticity reached a balance(1807 MPa,14.05%).Accordingly,the friction coefficient and wear rate also showed a stable and decreasin

关键词： Selective laser melting H13 steel Solution aging Double aging Friction and wear Retained austenite

Geochronological and geochemical constraints on the petrogenesis and geodynamic process of Hemler,Vlinder,and Il'ichev seamount lavas in NW Pacific

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Science China Earth Sciences 2024年第6期67卷 1856-1871页

作者： Xun WEI yan ZHANG Xuefa SHI hui ZHANG Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Deep Sea Mineral Resources Development(Preparatory) Qingdao 266061China

Oceanic intraplate volcanoes with linear age progressions are usually accepted to be derived from melting of an upwelling mantle *** seamount groups in NW Pacific,however,show complex age-distance relationships that are difficult to explain using the classic“mantle plume hypothesis”,and thus their origins are *** this study,we present ^(40)Ar-^(39)Ar age,geochemical,and Sr-Nd-Pb-Hf isotopic data of lavas from Hemler,Vlinder,and Il’ichev seamounts in NW Pacific,to elucidate their petrogenesis and geodynamic *** lavas from Hemler,Vlinder,and Il’ichev seamounts are classified as alkali basalt,basanite/nephelinite,and *** with Mg O>8 wt.%exhibit high contents of CaO,FeO^(T),and TiO_(2),similar to the composition of melts formed from reaction between carbonated eclogite-derived melts and fertile *** lavas have elevated Zr/Hf ratios(40.6-45.2)and negative Zr and Hf anomalies,indicating the presence of a carbonate component in the mantle *** are enriched in incompatible trace elements and have enriched mantle 1(EM1)-like SrNd-Pb-Hf isotopic *** isotopic compositions of Vlinder,Il’ichev basanite,and Hemler lavas in this study are similar to the Rarotonga *** occurring at the same seamount,the Il’ichev alkali basalts display more depleted SrNd-Hf isotopic compositions compared to Il’ichev *** to plate tectonic reconstruction results,the ages of Hemler(100.1 Ma),Vlinder pre-(100.2 Ma)and post-shield(87.5 Ma),and Il’ichev(56.4 Ma)lavas clearly deviate from the Macdonald,Arago,Rarotonga,and Samoa hotspot tracks,indicating that they cannot directly originate from mantle *** propose that in the mid-Cretaceous,when the Pacific plate passed over Rarotonga hotspot,melting of Rarotonga plume formed the Vlinder(main-shield stage),Pako,and Ioah *** Rarotonga(and possibly Samoa)plume materials would have been dispersed into the surrounding asthenosphere by mantle conve

关键词： Mantle plume Magellan seamount trail Carbonated mantle component Hotspot Lithosphere extension