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Study on open charm hadron production and angular correlation in high-energy nuclear collisions

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Nuclear Science and Techniques 2021年第1期32卷 10-16页

作者： Hai Wang jin-hui Chen Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China

We study the production and angular correlationof charm hadrons in hot and dense matter produced in high-energy nuclear-nuclear collisions within a multiphasetransport model(AMPT).By triggering additional charm-anticharm quark pair production in the AMPT,the modeldescribes the D^0 nuclear modification factor in the low andintermediate pr regions in Au+Au collisions at√VSNN=200 GeV reasonably *** exploration of the D^0 pair azimuthal angular correlation for different centralitiesshows clear evolution from low-multiplicity to high-mul-tiplicity events,which is associated with the number ofcharm quark interactions with medium partons duringAMPT transport.

关键词： Heavy-ion collision Heavy flavor Nuclear modification factor Two-particle correlations

Anisotropy flows in Pb-Pb collisions at LHC energies from parton scatterings with heavy quark trigger

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Nuclear Science and Techniques 2022年第2期33卷 14-20页

作者： Hai Wang jin-hui Chen Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China

By implementing an additional heavy quark-antiquark pair production trigger in a multiphase transport(AMPT)model,we study the effect on anisotropy flows of identified particles with a focus on charged particles and quarkonium(J/ΨandΥ).A systematic increase in the collision rate for active partons in the AMPT model with such an implementation has been *** leads to a slight increase of identified particles anisotropy flows as a function of transverse momentum(pT)and rapidity,and gives a better description of the experimental data of elliptic flow toward larger *** approach provides an efficient way to study the heavy quark dynamics in the AMPT model at LHC energies.

关键词： Heavy-ion collision Quark-gluon plasma Quarkonium Collective flow

Unsteady rotating flows of a viscoelastic fluid with the fractional Maxwell model between coaxial cylinders

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Acta Mechanica Sinica 2006年第4期22卷 301-305页

作者： Haitao Qi hui jin Department of Applied Mathematics and Statistics Institute of Applied Mathematics Shandong University at Weihai Weihai 264209 Shandong China School of Mathematics and Systematical Science Shandong University Jinan 250100 Shandong China

The fractional calculus is used in the constitutive relationship model of viscoelastic fluid. A generalized Maxwell model with fractional calculus is considered. Based on the flow conditions described, two flow cases are solved and the exact solutions are obtained by using the Weber transform and the Laplace transform for fractional calculus.

关键词： Viscoelastic fluid Unsteady flow Fractional Maxwell model Exact solution

Simulation Study on Hydrogen-Heating-Power Poly-Generation System based on Solar Driven Supercritical Water Biomass Gasification with Compressed Gas Products as an Energy Storage System

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Journal of Thermal Science 2020年第2期29卷 365-377页

作者： jin hui WANG Cui FAN Chao State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

Supercritical water gasification driven by solar energy is a promising way for clean utilization of biomass with high moisture content, but direct discharge of liquid residual causes energy waste and decreases energy efficiency. To reduce energy waste, a poly-generation system for hydrogen-rich gas production coupling heat supply and power generation based on supercritical water gasification of biomass driven by concentrated solar energy was established in this paper, which also provided a novel energy storage method to overcome the shortcomings of solar discontinuity. Thermodynamic model of the system was proposed and life cycle assessment(LCA) of the system was conducted. Influence of different parameters(temperature of 600℃ to 800℃, outlet temperature of heat exchanger of 42℃ to 56℃, biomass slurry concentration of 5% to 6.5%) on the gasification performance, energy and exergy efficiency, energy distribution and global warming potential(GWP) was discussed. The results indicated that hydrogen yield increased as gasification temperature increased since free radical reaction was enhanced which gas production reaction was classified into. Molar fraction of hydrogen increased as gasification temperature increased and reached 65.6% at 750℃. Energy and exergy efficiency of the system reached 74.84% and 34.87% at 700℃ and 600℃ respectively and that of gas production was 18.15% at 650℃, which was the highest. Increasing reaction temperature and decreasing biomass slurry concentration were effective ways to decrease GWP. Optimal operating parameter was reaction temperature of 650℃, outlet temperature of heat exchanger of 50℃ and biomass concentration of 5%.

关键词： biomass supercritical water gasification poly-generation system thermodynamics analysis energy storage life cycle assessment

Microstructure and mechanical properties of 2219 aluminum alloy VPTIG welds during cyclic thermal treatment

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Rare Metals 2022年第10期41卷 3539-3545页

作者： Di-Yao Su hui-jin jin Su-Jun Wu School of Materials Scienceand Engineering Beihang UniversityBeijing 100191China

In this study,the effect of the cyclic thermal treatment(CTT) on the microstructure and mechanical properties of the 2219 Al alloy welds fabricated using variable polarity tungsten inert gas(VPTIG) arc welding method were investigated by optical microscope(OM),transmission electron microscope(TEM),and low-temperature tensile tests,with emphasis on precipitation evolution and property variation in different areas of the *** of the microhardness profile across the weld reveals that there are maximum and minimum hardness values in the heat-affected zone(HAZ) adjacent to the fusion boundary(FB).It is found that the maximum hardness value increases with the temperature cycles of the cyclic thermal treatment due to the formation of GuinierPreston(GP) zones,while the microhardness at other positions remains *** results show that the CCT results in an increase in the yield strength,but a decrease in the ductility of the weld joint.

关键词： 2219 aluminum alloy VPTIG weld Microstructure Microhardness

Ligand-free Copper-catalyzed Synthesis of Symmetrical Diynes from 1,1-Dibromo-1 -alkenes

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Chinese Journal of Chemistry 2011年第3期29卷 592-594页

作者： jin, hui Kuang, Chunxiang Department of Chemistry Tongji University Shanghai 200092 China

Symmetrical diynes were synthesized by ligand-free copper-catalyzed homocoupling reaction of 1,1-dibromo-1- alkenes using a DBU/DMSO system at room temperature in good to excellent yields.

关键词： symmetrical diynes copper-catalyzed 1,1-dibromo-l-alkenes ligand-free homocoupling

Molecular Characterization of Three Ethylene Responsive Element Binding Factor Genes from Cotton

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Journal of Integrative Plant Biology 2010年第5期52卷 485-495页

作者： Long-Guo jin hui Li jin-Yuan Liu Laboratory of Molecular Biology and MOE Laboratory of Protein Science Department of Biological Sciences and Biotechnology TsinghuaUniversity Beijinq 100084 China

Ethylene-responsive factors （ERFs） are important regulators of plant gene expression. In this study, three novel ERF genes, GhERF2, GhERF3 and GhERF6, were isolated from cotton （Gossypium hirstum） using rapid amplification of cDNA ends-polymerase chain reaction. Transient expression analysis using GhERF-green fluorescent protein fusions showed that these three proteins were targeted to the nucleus. Fusion proteins consisting of GhERF2, GhERF3 or GhERF6 coupled to the GAL4 DNA binding domain strongly activated transcription in yeast. Furthermore, GhERF6 was shown to be able to bind specifically to GCC boxes using a particle bombardment assay in tobacco cells. Semi-quantitative reverse transcription-polymerase chain reaction revealed that GhERF2 and GhERF3 are constitutively expressed in all organs, while GhERF6 is only constitutively expressed in vegetative organs. When plants were treated with ethylene, abscisic acid, salt, cold and drought, the transcripts of GhERF2, GhERF3 and GhERF6 were rapidly induced to high levels. Promoter analysis also indicated that the 5＇ upstream regions of the three genes possess elements induced by these physiological and environmental factors. Collectively, our data suggest that GhERF2, GhERF3 and GhERF6 might function as positive trans-acting factors in the plant responses to ethylene, abscisic acid and other stresses and provide useful clues for further research into the mechanism of them in regulating cotton multiple stress responses.

关键词： Ethylene Cotton Gossypium Regulations Plants Planting Uses Genes ABA Lymphocytes

Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： jin-hui Ye Dan Shi Yue-Sheng Qi jin-hui Gao Jian-Xin Shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Modeling and Simulation of Diaphragm Spring Clutch

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Journal of Beijing Institute of Technology 2017年第3期26卷 340-348页

作者： hui jin Fanjing Meng School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

A model was developed to simulate a vehicle diaphragm spring clutch with the evaluation indicators of jerk degree and friction ***,the pressing load characteristic of the driven plate of the diaphragm spring clutch was ***,the clutch dynamic characteristic under each state was studied according to the basic principles of ***,the mathematical model of the clutch was *** on the model,the performance of a vehicle was *** simulation results show that the model can predict the dynamic characteristic of the clutch correctly and evaluate the performance of the clutch engagement *** model can be used for theoretical research of automatic clutch control and can be easily applied to simulate vehicle longitudinal dynamics.

关键词： diaphragm spring clutch pressing load characteristic vehicle longitudinal dynamics simulation model MATLAB/Simulink