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Characterization of the globular oxide inclusion ratings in steel using laser-induced breakdown spectroscopy

Frontiers of physics 2016年第6期11卷 273-279页

作者： Yong Zhang Yun-Hai Jia Chun Yang Dong-Ling Li Jia Liu Yong-Yan Chen ying Liu yi-xiang duan Research Center of Analytical Instrumentation Key Laboratory of Bio-Resource and Eco-Environment Ministry of Education College of Life Science Sichuan University Chengdu 610064 China Central Iron and Steel Research Institute Beijing 100081 China NCS Testing Technology Co. Ltd. Beijing 100094 China General Research Institute of Nonferrous Metals Beijing 100088 China

Grade assessment of steel is generally performed via the metallographic method, which is time-consuming and is not able to provide the elemental distribution information. In this paper, we present a method to measure the globular oxide inclusion ratings in steel using laser-induced breakdown spectroscopy (LIBS). The measurement is performed in two basic steps: steel samples are polished using metallographic sand paper and the Al2O3 inclusion number and size distribution in a marked area are observed using scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDS) for further LIBS scanning analysis. The threshold intensity that distinguishes soluble aluminum and insoluble aluminum inclusions is determined using LIBS combined with the SEM/EDS statistical data. Carbon steel (the sample number is S9256) and bearing steel (the sample number is GCr15) are analyzed in scanning mode, and the number of Al2O3 inclusions in different size ranges is obtained from the statistical information derived from the Al2O3 size calibration curve. According to heavy and thin series for globular oxide inclusions grade assessment, the method we propose is comparable to the traditional metallographic method in terms of accuracy; however, the process is simplified and the measurement speed is significantly improved.

关键词： laser-induced breakdown spectroscopy (LIBS) globular oxide inclusion steel grade assessment elemental distribution

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EVALUATON OF MICROWAVE PLASMA TORCH FOR ATOMIC FLUORESCENCE SPECTROMETRY WITH AN ULTRASONIC NEBULIZATION SAMPLE INTRODUCTION SYSTEM

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Chinese Chemical Letters 1993年第7期4卷 615-618页

作者： yi Mu LI yi xiang duan Jun LIU Qin Han JIN Department of Chemistry, Jilin University, Changchun, 130O23

In this paper, a new MPT(microwave plasma torch) device has been used as a atomizer for atomic fluorescence spectrometry. Spme elements, such as Zn, Cd, Hg, Pb, As, Co, Mg, Cu, Ag, Mn, Fe have been investigated in det... 详细信息

关键词： TORCH EVALUATON OF MICROWAVE PLASMA TORCH FOR ATOMIC FLUORESCENCE SPECTROMETRY WITH AN ULTRASONIC NEBULIZATION SAMPLE INTRODUCTION SYSTEM Cd USN Long HCL MPT

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Investigation and identification of breath acetone as a potential biomarker for type 2 diabetes diagnosis

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Chinese Science Bulletin 2014年第17期59卷 1992-1998页

作者： Mei-Gui Zhou Yong Liu Wen-Wen Li Xin Yuan Xue-Fang Zhan Jie Li yi-xiang duan Yu Liu Zhao-Hua Gao Yan Cheng Shou-Quan Cheng Hong Li Yuan Liang Research Center of Analytical Instrumentation Analytical & Testing CenterSichuan University Department of Endocrinology The Second Affiliated Hospital of Jilin University 208th Hospital of People’s Liberation Army

Acetone is regarded as a promising biomarker for the noninvasive diagnosis and monitoring of *** collected breath acetone from 25 type 2 diabetics(T2D)and 44 healthy subjects using aluminum foil bags(3 L),and the samples were analyzed by gas chromatography–mass spectrometry.T2D patients had significantly higher acetone levels(mean=2.167 ppmv(1 ppmv=1 lL/L),standard error(SE)=0.231)than healthy volunteers(mean=0.488 ppmv,SE=0.025;P\0.0001).The receiver operating characteristics curve showed that the optimum diagnostic cutoff value for exhaled acetone was 0.891 ppmv(area under the curve 0.999,sensitivity 100%,and specificity 97.7%)in T2D patients relative to healthy ***,breath acetone could be a useful marker for the high accuracy diagnosis and monitoring of *** addition,the ratios of the mean acetone concentration in ambient air relative to that in the total exhaled air and in the net exhaled air were 1:18 and 1:17,*** post-breakfast acetone concentrations(mean=0.437 ppmv,SE=0.035)were slightly lower than the pre-breakfast levels(mean=0.553 ppmv,SE=0.047;P[0.05).Thus,the increased acetone concentrations in T2D patients are affected strongly by physiological factors related to the disease,rather than the ambient air and diet.

关键词： 2型糖尿病生物标志物诊断性丙酮呼吸鉴定气相色谱平均值

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About the Energy of the Universe

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Chinese Physics Letters 1996年第6期13卷 409-411页

作者： FENG Shi-xiang duan yi-shi Institute of Nuclear Research Chinese Academy of SciencesShanghai 201800 Institute of Theoretical Physics Lanzhou UniversityLanzhou 730000

We use the general covariant conservation law of energy-momentum,which is general covariant and therefore preferable to the non-covariant conservation laws,to analyse the energy of the universe and obtained vanishing ... 详细信息

关键词： energy vanishing discussions

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Preparation of gangue ceramsite by sintering pot test and potential analysis of waste heat recovery from flue gas

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Journal of Iron and Steel Research International 2023年第7期30卷 1401-1410页

作者： yi Huang xiang-jie duan Yu Li Wei Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Preparation of ceramsite from solid waste based on the sintering process is a new technology and had a high efficiency in improving producing capability, decreasing consumption of liquefied petroleum gas (LPG), and recovering waste heat of flue gas. An experiment sintering gangue ceramsite was conducted in a 25 kg scale sintering pot with a 100 cm height. The combustion characteristics, phase transformation, and the release profile of SO_(2)^(*) (SO and/or SO_(2)) and NO_(x)^(*) (N_(2)O, NO, and/or NO_(2)) of gangue ceramsite during the sintering process were studied by X-ray diffraction analysis, X-ray fluorescence spectrometry, thermogravimetry–differential thermogravimetry–differential scanning calorimetry, and measurement of physical properties of ceramsite and gas components of flue gas. The results showed that the gangue ceramsite had excellent properties, and its compressive strength and water absorption were 8.2–9.6 MPa and 8.9%–9.8%, respectively, far exceeding the requirement of standard (GB/T 17431.1–2010). The ignition temperature of gangue ceramsite was 443 ℃, and the ignition loss was 14.60 mass% at 1000 ℃. Kaolinite and calcite disappeared at 600 and 800 ℃, respectively. Albite disappeared and mullite formed at 1000 ℃. Two peaks of SO_(2)^(*) emissions emerged in the range of 311–346 mg m^(-3) near 500 ℃ of upper layer ceramsite and 420–489 mg m^(-3) near 1000 ℃ of lower layer ceramsite, respectively. NO_(x)^(*) emissions peak emerged in the range of 227–258 mg m^(-3) near 550 ℃ of the upper layer ceramsite, which was related to the oxidation of sulfide and the combustion of LPG. Gangue is a direct heat source for sintering of ceramsite as well. During sintering process, the heat of flue gas above and below 400 ℃ accounts for 55.9% and 30.0% of the all-output heat, respectively, and was potentially used for producing waste-heat steam or electricity as by-products and drying raw materials during its own initial sintering process, which can realize comb

关键词： Gangue ceramsite Cogeneration SO_(2)^(*) NO_(x)^(*) Flue gas waste heat

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High-Order Fully Actuated System Models for Strict-Feedback Systems With Increasing Dimensions

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IEEE/CAA Journal of Automatica Sinica 2024年第12期11卷 2451-2462页

作者： xiang Xu Guang-Ren duan Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology the School of System Design and Intelligent Manufacturing Southern University of Science and Technology

This paper mainly addresses control problems of strict-feedback systems(SFSs) with increasing dimensions. Compared with the commonly-considered SFSs where the subsystems have the same dimension, we aim to handle more complex cases,i.e., the subsystems in the considered SFSs are assumed to have increasing dimensions. By transforming the systems into highorder fully-actuated system(HOFAS) models, the stabilizing controllers can be directly given. Besides first-order SFSs, secondorder and high-order SFSs are also considered.

关键词： Increasing dimensions high-order fully-actuated system nonlinear systems strict-feedback systems

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Relationship Between Short-chain Fatty Acids and Parkinson’s Disease:A Review from Pathology to Clinic

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Neuroscience Bulletin 2024年第4期40卷 500-516页

作者： Wen-xiang duan Fen Wang Jun-yi Liu Chun-Feng Liu Department of Neurology and Clinical Research Center of Neurological Disease The Second Affiliated Hospital of Soochow UniversitySuzhou215004China Department of Neurology Dushu Lake Hospital affiliated to Soochow UniversitySuzhou215125China Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience Soochow UniversitySuzhou215123China

Parkinson’s disease(PD)is a complicated neurodegenerative disease,characterized by the accumulation ofα-synuclein(α-syn)in Lewy bodies and neurites,and massive loss of midbrain dopamine *** evidence suggests that gut microbiota and microbial metabolites are involved in the development of *** these,short-chain fatty acids(SCFAs),the most abundant microbial metabolites,have been proven to play a key role in brain-gut *** this review,we analyze the role of SCFAs in the pathology of PD from multiple dimensions and summarize the alterations of SCFAs in PD patients as well as their correlation with motor and non-motor *** research should focus on further elucidating the role of SCFAs in neuroinflammation,as well as developing novel strategies employing SCFAs and their derivatives to treat PD.

关键词： Parkinson’s disease Short-chain fatty acids Microbial metabolites Brain-gut-microbiota axis

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Electrorheological effect of Ti-bearing blast furnace slag with different TiC contents at 1500°C

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 768-775页

作者： Hong-rui Yue Tao Jiang Qiao-yi Zhang Pei-ning duan xiang-xin Xue School of Metallurgy Northeastern University Shenyang 110819 China Liaoning Key Laboratory of Metallurgical Resources Recycling Science Engineering and Technology Research Center for Boron Resource ComprehensiveDevelopment and Application of Liaoning Province Liaoning Key Laboratory for Ecological Comprehensive Utilization of Boron Resources and Materials Shenyang110819 China

The electrorheological properties of CaO–SiO2–Al2O3–MgO–TiO2–Ti C slags were investigated to enhance understanding of the effect of TiC addition on the viscosity, yield stress, and fluid pattern of Ti-bearing slags in a direct-current electric field. The viscosities and shear stresses of 4wt% and 8wt% Ti C slags were found to increase substantially with increasing electric field intensity, whereas virtually no rheological changes were observed in the 0wt% TiC slag. The Herschel–Bulkley model was applied to demonstrate that the fluid pattern of the 4wt% TiC slag was converted from that of a Newtonian fluid to that of a Bingham fluid in response to the applied electric field; and the static yield stress increased linearly with the square of the electric field intensity.

关键词： electrorheology viscosity Ti-bearing slag titanium carbide

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Design and simulation of the ATP system considering the advanced targeting angle in quantum positioning system

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1227-1236页

作者： CONG Shuang ZHANG xiang duan Shiqi Department of Automation University of Science and Technology of ChinaHefei 230027China

A compensation implementation scheme of the advanced targeting process based on the fine tracking system is proposed in this *** on the working process of the quantum positioning system(QPS)and its acquisition,tracking and pointing(ATP)system,the advanced targeting subsystem of the ATP system is *** on six orbital parameters of the quantum satellite Mozi,the advanced targeting azimuth angle and pitch angle are transformed into the dynamic tracking center of the fine tracking system in the ATP *** deviation of the advanced targeting process is *** the Simulink,the simulation experiment of the ATP system considering the deviation compensation of the advanced targeting is carried out,and the results are analyzed.

关键词： quantum positioning system(QPS) acquisition tracking and pointing(ATP) advanced targeting

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Progress in flight tests of hypersonic boundary layer transition

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Acta Mechanica Sinica 2021年第11期37卷 1589-1609,I0001页

作者： Guohua Tu Jianqiang Chen Xianxu Yuan Qingtao Yang Maochang duan Qiang Yang yi duan Xi Chen Bingbing Wan Xinghao xiang State Key Laboratory of Aerodynamics China Aerodynamics Research&Development CenterMianyang621000China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing100076China

Boundary layer transition(BLT)can cause a sharp rise in heat flux and skin friction,which can seriously affect the flight performance and safety of hypersonic flight ***,the mechanism,prediction and control of transition have become important issues that must be dealt with for the development of advanced flight vehicles,and it is also a research hotspot of particular interest to major aerospace *** to other transition research approaches,model flight tests can better present the transition problems under real flight conditions,thus have been carried out extensively over the past 30 *** United States,Germany,France,Australia,and other countries have carried out transition research based on flight tests,such as the Pegasus wing-glove crossflow transition and the Hypersonic Boundary Layer Transition(HyBOLT)transition control flight test of the United States,the joint research project of the Hypersonic International Flight Research and Experimentation-1(HIFiRE-1)circular cone and the HIFiRE-5 elliptic cone transition flight tests between the United States and Australia,the flight test of compression surface transition of the scramjet forebody(LEA)in France and so *** these flight tests suffered various setbacks,they still obtained valuable transition ***,the United States is carrying out the concave-surface transition flight tests of Hypersonic Boundary Layer Transition(BOLT)and *** its first model flight test mission for verification purpose launched successfully in 2015,several hypersonic BLT flight tests have been conducted by China Aerodynamics Research and Development Center(CARDC).The flight tests have measured valid transition data under flight conditions,obtained the transition front and its dynamical variation on blunt cones at various angles of attack and a lifting body Hypersonic Transition Research Vehicle(HyTRV).The crossflow traveling waves in high-altitude flight were measured for the first t

关键词： Hypersonic flow Boundary layer transition Flight test MF-1 HyTRV

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