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Influence of angle’s ranges for recording an X-ray fluorescence hologram on reconstructed atomic images

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Nuclear Science and Techniques 2004年第3期15卷 160-165页

作者： XIEHong-Lan CHENJian-wen gaohong-Yi ZHUHua-Feng LIRu-Xin XUZhi-Zhan ShanghaiInstituteofOpticsandFineMechanics theChineseAcademyofSciencesShanghai201800

X-ray fluorescence holography (XFH) is a novel method for three-dimensional (3D) imaging of atomic structure. Theoretically, in an XFH experiment, one has to measure the fluorescence energy on a spherical surface to get well-resolved 3D images of atoms. But in practice, the experimental system arrangement does not allow the meas- urement of the fluorescent intensity oscillations in the full sphere. The holographic information losses because of the limited sampling range (less than 4π) will directly result in defective reconstructed atomic images. In this work, the atomic image of a Fe single crystal (001) was reconstructed by numerically simulating X-ray fluorescence holograms of the crystal at different recording angle’s ranges and step lengths. Influences of the ranges of azimuth angles and polar angles and the step length of polar angles on the reconstructed atomic images were discussed.

关键词： X射线荧光全息摄影晶体结构傅立叶变换原子图像重建

Design and experimental study of the end-effector for broccoli harvesting

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 137-144页

作者： Xiong Zhao Gangji Xu Pengfei Zhang gaohong Yu Yadan Xu Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Transplanting Equipment and Technology of Zhejiang Province Hangzhou 310018China Hangzhou vocational&Technical College Hangzhou 310018China

The end-effector is an important part of the broccoli harvesting *** at the physical characteristics of a large broccoli head and thick stem,a spherical cutting tool broccoli harvesting end-effector was designed in this ***,the physical characteristics of broccoli were tested,and physical parameters such as the broccoli head diameter and stem diameter of broccoli were *** maximum cutting force of broccoli stems under different cutting angles was ***,according to the physical characteristics and harvesting process of broccoli,the end-effector was designed,and the mathematical model of kinematics and dynamics was *** on the results of dynamic analysis,the end-effector rod was optimized,and the unilateral width of the slider was 40 mm,the length of the connecting rod was 120 mm,and the length of the crank was 42 *** mechanism needed an external driving force of 140.54 N to cut the broccoli ***,a 32 mm cylinder with a load rate of 50%was selected as the power ***,the feasibility of the broccoli harvesting end-effector was verified by the harvesting *** showed that the overall harvesting success rate of the end-effector is 93.3%,and the smoothness rate of the stem section is 83.3%.The harvesting performance of the broccoli end-effector was *** lays a foundation for agricultural robots to harvest broccoli.

关键词： harvesting robot broccoli end-effector dynamic analysis mechanism optimization

Polymeric hollow fiber membrane for cooling crystallization seeding:On the mechanism of induced nucleation based on thermal transfer Author links open overlay panel

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Particuology 2024年第8期91卷 38-49页

作者： Zeman He Shaofu Du Guanying Shao Peiyu Li Lei Sheng gaohong He Xiaobin Jiang Wu Xiao State Key Laboratory of Fine Chemicals School of Chemical EngineeringEngineering Laboratory for Petrochemical Energy-efficient Separation Technology of Liaoning ProvinceDalian University of TechnologyDalian 116024China

Cooling crystallization is an important separation process and particuology technology that requires accurate nucleation control ***,we introduced the polymeric hollow fiber membrane with proper thermal properties as the effective nucleation induction interface during cooling *** heterogeneous nucleation control mechanism was introduced based on classical nucleation theory and the thermal transfer *** properties and the thermal conductivity of two kinds of polymeric membranes,polytetrafluoroethylene(PTFE)and polyethersulfone(PES),were measured and simulated with the developed *** two membranes possessed different nucleation induction periods,nucleation rates and crystallization performances,which validated that the hollow fiber membrane module could effectively accelerate the nucleation process compared to conventional cooling crystallization owing to the shorter nucleation induction period and the reduced solution surface *** to the higher hydrophobicity and the lower roughness of the membrane surface,the PTFE membrane possessed a more moderate performance in generating stable heterogeneous nucleation than the one of PES ***,the adjustable membrane property enabled the hollow fiber membrane-assisted cooling crystallization to possess the accurate nucleation control and desired terminal particle products.

关键词： Cooling crystallization Nucleation Particle process Hollow fiber membrane Induction period Process control

Supersaturation-driven self-assembly formation of ceftriaxone sodium spherulites:From amorphous form to spherulites

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Particuology 2024年第7期90卷 10-19页

作者： Shankun Liang Yuchao Niu Xueyan Hu Wu Xiao Xuehua Ruan gaohong He Xiaobin Jiang State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsSchool of Chemical EngineeringDalian University of TechnologyDalian116024China School of Chemical Engineering at Panjin Dalian University of TechnologyPanjin124221China

Drug particles with spherical morphology possess amazing advantages in terms of particle flowability,mechanical properties,drug solubility,and *** growth mechanism of drug spherulite is of great importance for the preparation and regulation of ***,ceftriaxone sodium spherulites were fabricated by the antisolvent crystallization method using dropwise addition of ceftriaxone sodium solution to *** observation of the whole crystallization process combined with electron microscopy technique revealed the spherical growth process from amorphous form to *** the supersaturation of the crystallization system was adjusted,the ceftriaxone sodium crystals transformed from amorphous form to *** the process of antisolvent crystallization with acetone as antisolvent,when the theoretical supersaturation degree S was higher than 2.62,the crystallization system tended to appear amorphous form;when S was between 2.57 and 2.62,the amorphous form transformed into clustered spherulites;when S was less than 2.57,the surface of spherulites will be covered with flaky crystal,which transformed into urchin-like *** the understanding of the spherical growth mechanism,the ceftriaxone sodium spherulites prepared in this research with modified supersaturation control had a low residue of antisolvent acetone,and the flowability was significantly improved.

关键词： Spherulite Ceftriaxone sodium Antisolvent crystallization Supersaturation Online observation

Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 91-99页

作者： Bingliang Ye Yuxuan Ye Haili Zhou gaohong Yu Xiong Zhao Bin Deng Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Zhejiang Province Key Laboratory of Transplanting Equipment and Technology Hangzhou 310018China Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310018China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical *** working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried *** study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting *** parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting *** on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the *** high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting *** test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design

Thermodynamic theory of flotation for a complex multiphase solid -liquid system and high-entropy flotation

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1177-1197页

作者： Shuming wen State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation ***,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral ***,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to *** addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation *** this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral *** homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain *** flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption *** to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency

关键词： multicomponent flotation reagent adsorption entropy change equations of thermodynamic equilibrium adsorption equilibri-um constant high-entropy flotation

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论加强会计基础工作的必要性

吉林商业高等专科学校学报 2006年第4期 65-66页

作者：高洪文四平市商业学校吉林四平136000

会计基础工作是会计工作的基本环节,也是经济管理工作的重要基础。在新的形势下,分析研究会计基础工作的范围、现状、及加强会计基础工作的必要性具有重要的意义。

关键词：会计会计基础工作会计记帐凭证财务报告必要性会计基础工作是会计工作的基本环节,也是经济管理工作的重要基础.本文就会计基础工作的范围、现状及加强会计基础工作的必要性作一探讨.

Goal-Oriented Control Systems(GOCS):From HOW to WHAT

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 816-819页

作者： wen-Hua Chen the Department of Aeronautical and Automotive Engineering Loughborough UniversityLeicestershireLE113TUU.K.

Brief:New control theory is required to underpin safe design and deployment of future highly automated systems to deal with uncertain environments and complicated tasks,enabled by AI and other advanced ***-Oriented Control Systems offer potential to transform the control system design from currently instructing a control system how to perform a task to specifying what is to be achieved.

关键词： automated instru system

Flow characteristics and bubble statistics during the fragmentation process of the ingested main cavity in plunging breaking waves

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Journal of Hydrodynamics 2024年第3期36卷 546-555页

作者： wen-bin Zhang Wei-wen Zhao De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

Plunging breaking waves play an important role in the exchange of heat,momentum,and mass between the atmosphere and *** this paper,a series of direct numerical simulations is conducted to investigate the fragmentation process of the ingested main cavity in plunging breaking *** two-phase Navier-Stokes equations are solved using the finite-volume method based on adaptive refinement *** free surface is captured using a geometrical volume of fluid *** 2-D,3-D simulations are *** flow fields at different stages of wave breaking are presented and quantitative analysis for bubbles is *** 2-D instantaneous vorticity field and local velocity field are visualized to discuss the general flow characteristics during the fragmentation *** a 2-D parametric study is conducted to investigate the differences in the flow characteristics during the fragmentation process under different wave parameters including initial wave steepness(ε),Bond number(Bo),and Reynolds number(Re).3-D vortex structures are shown to further investigate the mechanisms behind the differences in the flow *** bubble size distributions under two different initial wave steepness are also discussed with their relationship to the fragmentation process of the ingested main *** research offers a significant understanding of the distinct procedures and fundamental dynamics involved in wave breaking,enhancing our comprehension of this intricate event.

关键词： Plunging breaking waves multiphase flow bubble statistics