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Nuclear Science and Techniques 2024年第4期35卷 119-135页

作者： Chuang Shen Ying-Shun Zhu Fu-san chen China Spallation Neutron Source Institute of High Energy PhysicsChinese Academy of Sciences1 Zhongziyuan RoadDongguan 523000China Institute of High Energy Physics Chinese Academy of Sciences19B Yuquan RoadBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and ***,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications *** with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical *** this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are *** analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current ***,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed.

关键词： Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design

Synthesis,Crystal Structure and Nonisothermal Kinetics of Complex Co(tda)(5-mphen)(H_2O)

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Chemical Research in Chinese Universities 2009年第3期25卷 383-387页

作者： HOU Xiang-yang chen san-ping GAO Sheng-li Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education College of Chemistry ＆ Materials Science Northwest University Xi＇an 710069 P. R. China Department of Chemistry Yan＇an University Yan＇an 716000 P. R. China

The title complex, formulated as Co（tda）（5-mphen）（H2O）（H2tda=thiodiglycolic acid, 5-mphen= 5-methyl-1,10-phenanthroline）, was synthesized and characterized by elemental analysis, IR spectroscopy, X-ray single crystal diffraction, and TG-DTG techniques. The complex crystallized in monoclinic space group C2/c, with parameters of a=1.8142（2） nm, b=0.78251（9） nm, c=2.4624（3） nm,β=93.809（2）°, V=3.4880（7） nm^3, Z=8, Dc=1.579 g/cm^3, the final R indices[1〉2σ（1）] are R1=0.0469, wR2=0.1021, R indices for all data are R1=0.0835, wR2=0.1169. The central Co^2＋ cation is coordinated in a distorted octahedral geometry with the ligand tda, 5-mphen, and water molecule. The coordination complex possesses a three-dimensional framework by means of hydrogen bonds and π-π stacking interactions. According to TG-DTG curves, the possible thermal decomposition mechanisms, the possible kinetic parameters, and equation of dehydration stage of the complex are obtained, that is, Ea=110.98 kJ/mol, lg（A/s^-1）=8.554, da/dT= 10^8.5546/β.3（1-α）[-1n（1-α）]^2/***（-13349/T）, respectively.

关键词： Co(tda)(5-mphen)(H2O) Crystal structure Kinetics of thermal decomposition

Preparation and Standard Formation Enthalpy of 2-Amino-4,6-dimethylpyrimidine and Its Related Complexes of Copper

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Chemical Research in Chinese Universities 2003年第4期19卷 459-463页

作者： chen san-ping WEI Qing JIAO Bao-juan GAO Sheng-li Shaanxi Key Laboratory of Physico-Inorganic Chemistry Department of ChemistryNorthwest UniversityXi′an 710069P.R.China

The complexes of hydrous copper chloride and copper nitrate with 2-amino-4,6-dimethylpyrimidine(ADMP) were prepared via reflux in alcohol. The compositions of the complexes were identified as Cu(ADMP) 2Cl 2·2H 2O(b) and Cu(ADMP)(NO 3) 2·H 2O(c) by chemical and elemental analyses. The complexes were characterized by IR, XPS, 1H NMR and TG-DTG techniques. The constant-volume combustion energies of ADMP and the complexes, Δ c E , were determined by a precise rotating-bomb calorimeter at 298 15 K. They were (-3664 53±1 18), (-4978 47±2 72) and (-1696 70±1 36) kJ/mol, respectively. Their standard enthalpies of combustion, Δ c H 0 m, and standard enthalpies of formation, Δ f H 0 m, were calculated to be (-3666 39±1 18), (-4977 23±2 72), (-1691 12±1 36) kJ/mol and (19 09±1 43), (-2041 80±3 29), (-2397 24±1 65) kJ/mol, respectively.

关键词： Copper salt 2-Amino-4,6-dimethylpyrimidine Standard enthalpy of combustion Standard enthalpy of formation

Manipulating submolecular-scale phototautomerization

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Science China Materials 2024年第6期67卷 2048-2050页

作者： ping Zhou Hongliang chen Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310058China Zhejiang-Israel Joint Laboratory of Self-Assembling Functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215China

A recent study on the submolecular-scale control of phototautomerization methods and the underlying reaction mechanisms was reported in Nature Nanotechnology by Guillaume and co-workers[1],elucidating how the field confinement effect generated by the scanning tunneling microscope(STM)tip precisely triggers the phototautomerization of a free-base phthalocyanine at the submolecular level and demonstrating that the reaction process can be finely controlled by adjusting either the laser excitation wavelength or the position of the tip.

关键词： tunneling excitation phthalocyanine

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1661-1667页

作者： Gu-jun chen Sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

Privacy-Preserving Consensus-Based Distributed Economic Dispatch of Smart Grids via State Decomposition

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1250-1261页

作者： Wei chen Guo-ping Liu The authors are with the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

This paper studies the privacy-preserving distributed economic dispatch(DED)problem of smart *** autonomous consensus-based algorithm is developed via local data exchange with neighboring nodes,which covers both the islanded mode and the grid-connected mode of smart *** prevent power-sensitive information from being disclosed,a privacy-preserving mechanism is integrated into the proposed DED algorithm by randomly decomposing the state into two parts,where only partial data is *** objective is to develop a privacy-preserving DED algorithm to achieve optimal power dispatch with the lowest generation cost under physical constraints while preventing sensitive information from being *** this end,a comprehensive analysis framework is established to ensure that the proposed algorithm can converge to the optimal solution of the concerned optimization problem by means of the consensus theory and the eigenvalue perturbation *** particular,the proposed autonomous algorithm can achieve a smooth transition between the islanded mode and the grid-connected ***,rigorous analysis is given to show privacy-preserving performance against internal and external ***,case studies illustrate the feasibility and validity of the developed algorithm.

关键词： preserving autonomous mode

Low Temperature Heat Capacities and Thermodynamic Properties of Zinc L-Threonate Zn(C_4H_7O_5)_2(s) by Adiabatic Calorimetry

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Chemical Research in Chinese Universities 2008年第5期24卷 603-607页

作者： chen Jing-tao DI You-ying TAN Zhi-cheng chen san-ping GAO Sheng-li Department of Chemistry Shaanxi Educational College Xi＇an 710061 P. R. China College of Chemistry and Chemical Engineering Liaocheng University Liaocheng 252059 P. R. China Department of Chemistry Northwest University Xi＇an 710069 P. R. China

Low-temperature heat capacities of the solid compound Zn（C4H7O5）2（s） were measured in a temperature range from 78 to 374 K, with an automated adiabatic calorimeter. A solid-to-solid phase transition occurred in the temperature range of 295？322 K. The peak temperature, the enthalpy, and entropy of the phase transition were determined to be （316.269±1.039） K, （11.194±0.335） kJ？mol-1, and （35.391±0.654） J？K-1？mol-1, respectively. The experimental values of the molar heat capacities in the temperature regions of 78？295 K and 322？374 K were fitted to two polynomial equations of heat capacities（Cp,m） with reduced temperatures（X） and [X = f（T）], with the help of the least squares method, respectively. The smoothed molar heat capacities and thermodynamic functions of the compound, relative to that of the standard reference temperature 293.15 K, were calculated on the basis of the fitted polynomials and tabulated with an interval of 5 K. In addition, the possible mechanism of thermal decomposition of the compound was inferred by the result of TG-DTG analysis.

关键词： Zn(C4H7O5)2(s) Adiabatic calorimetry Low-temperature heat capacity Solid-to-solid phase transition Thermodynamic property TG-DTG

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research(International) 2024年第4期31卷 828-837页

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

A Blade Altering Toolbox for Automating Rotor Design Optimization

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Communications on Applied Mathematics and Computation 2024年第1期6卷 688-704页

作者： Akiva Wernick Jen-ping chen Mechanical and Aerospace Engineering The Ohio State University201 W.19th Ave.ColumbusOH43210USA

The Blade Altering Toolbox(BAT)described in this paper is a tool designed for fast reconstruction of an altered blade geometry for design optimization *** BAT algorithm is capable of twisting a given rotor’s angle of attack and stretching the chord length along the span of the *** test cases were run using the BAT’s *** BAT code’s twisting,stretching,and mesh reconstruction capabilities proved to be able to handle reasonably large geometric alterations to a provided input rotor *** test examples showed that the toolbox’s algorithm could handle any stretching of the blade’s chord as long as the blade remained within the original bounds of the unaltered *** algorithm appears to fail when the net twist angle applied the geometry exceeds approximately 30 degrees,however this limitation is dependent on the initial geometry and other input ***,the algorithm is a very powerful tool for automating a design optimization procedure.

关键词： Mesh reconstruction Mesh alteration Rotor alteration Design optimization

Identifying Brand Consistency by Product Differentiation Using CNN

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 685-709页

作者： Hung-Hsiang Wang Chih-ping chen Department of Industrial Design National Taipei University of TechnologyTaipeiTaiwan Department of Product Design Ming Chuan UniversityTaoyuanTaiwan

This paper presents a new method of using a convolutional neural network(CNN)in machine learning to identify brand consistency by product appearance *** Experiment 1,we collected fifty mouse devices from the past thirty-five years from a renowned company to build a dataset consisting of product pictures with pre-defined design features of their appearance and *** show that it is a challenge to distinguish periods for the subtle evolution of themouse devices with such traditionalmethods as time series analysis and principal component analysis(PCA).In Experiment 2,we applied deep learning to predict the extent to which the product appearance variation ofmouse devices of various *** investigation collected 6,042 images ofmouse devices and divided theminto the Early Stage and the Late *** show the highest accuracy of 81.4%with the CNNmodel,and the evaluation score of brand style consistency is 0.36,implying that the brand consistency score converted by the CNN accuracy rate is not always perfect in the real *** relationship between product appearance variation,brand style consistency,and evaluation score is beneficial for predicting new product styles and future product style *** addition,the CNN heat maps highlight the critical areas of design features of different styles,providing alternative clues related to the blurred *** study provides insights into practical problems for designers,manufacturers,and marketers in product *** not only contributes to the scientific understanding of design development,but also provides industry professionals with practical tools and methods to improve the design process and maintain brand *** can use these techniques to find features that influence brand ***,capture these features as innovative design elements and maintain core brand values.

关键词： Machine learning product differentiation brand consistency principal component analysis convolutional neural network computer mouse