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EXPERIMENTAL AND SIMULATED COMPRESSIVE PROPERTIES OF WORK-HARDENED X-TYPE LATTICE TRUSS STRUCTURES

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Acta Mechanica Solida Sinica 2012年第2期25卷 111-116页

作者： qiancheng Zhang Tianjian Lu MOE Key Laboratory of Strength&Vibration School of AerospaceXi'an Jiaotong UniuersityXi'an 710049China

The expanded metal sheets were folded with 11% work-hardening. These were sub- sequently used with resistance welding to construct X-type lattice truss sandwich panels having a core relative density of 0.17. The sandwich panels were tested in uniaxial compression and, for comparison, the method of finite elements was employed to simulate the measured compressive stress-strain curves. The peak compressive strength was 32% higher than that of pyramidal core sandwiches. The enhanced mechanical properties of the work-hardened X-Type lattice structures mainly originate from the contribution of straight struts with low degree of curvature and work hardening, rather than the two-dimensional staggered nodes.

关键词： sandwichs work hardening resistance welding X-type core

An Expeditious Route for the Total Synthesis of Pondaplin Isolated from Annona glabra

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Chinese Chemical Letters 2003年第12期14卷 1215-1218页

作者： qiancheng YanWenZHANG XiangZHANG TakayukiORITANI LaboratoryofAppliedBioorganicChemistry GraduateSchoolofAgriculturalScienceTohokuUniversitySendai981-8555Japan LaboratoryofMedicinalChemistry CollegeofPharmacyTianjinMedicalUniversityTianjin300203 InstituteofMateriaMedica ChineseAcademyofMedicalSciences＆PekingUnionMedicalCollegeBeijing100050

A novel cyclic prenylated phenylpropanoid, pondaplin 1, was first synthesized in 26% overall yields through an expeditious route (7 steps) that employed highly regio- and stereoselective phenyltellurenylation to aryla... 详细信息

关键词： Pondaplin total synthesis natural product.

The Interacting Boson Model of Dipole—Octupole Strong Correlations in SU（3） Limit for Positive Parity States

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Communications in Theoretical Physics 2003年第5期39卷 587-592页

作者： qiancheng-De LIUDang-Bo RENHao InstituteofTheoreticalPhysics DepartmentofPhysicsShanghaiJiaoTonguniversityShanghai200030China

Within the framework of the Usdpf(16) interacting boson model (IBM), the effects of strong correlations of the dipole (p?-boson) and the octupole (f?-boson) degree of freedom on the positive-parity states of even-even nuclei in SU(3) limit are discussed. It is shown that configurations of an even number of many p- and f-bosons can not only be incorporated into the usual low-lying collective rotational bands, such as the ground state band, β- and γ-vibrational bands, but also naturally form the rotational bands, etc. These results are similar to that of Usdg(15)-IBM and in good agreement with the experimental data of the nucleus. Besides, several intraband E2 transition probabilities are given, which are consistent with that of Usd(6)-IBM.

关键词： U-sdpf(16)-IBM dipole-octupole strong correlations Hf-176 K-pi=1(+), 3(+) rotational bands

User Purchase Intention Prediction Based on Improved Deep Forest

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 661-677页

作者： Yifan Zhang qiancheng Yu Lisi Zhang School of Computer Science and Engineering North Minzu UniversityYinchuan750030China Laboratory of Graphics and Images of the State Ethnic Affairs Commission North Minzu UniversityYinchuan750030China

Widely used deep neural networks currently face limitations in achieving optimal performance for purchase intention prediction due to constraints on data volume and hyperparameter *** address this issue,based on the deep forest algorithm and further integrating evolutionary ensemble learning methods,this paper proposes a novel Deep Adaptive Evolutionary Ensemble(DAEE)*** model introduces model diversity into the cascade layer,allowing it to adaptively adjust its structure to accommodate complex and evolving purchasing behavior ***,this paper optimizes the methods of obtaining feature vectors,enhancement vectors,and prediction results within the deep forest algorithm to enhance the model’s predictive *** demonstrate that the improved deep forest model not only possesses higher robustness but also shows an increase of 5.02%in AUC value compared to the baseline ***,its training runtime speed is 6 times faster than that of deep models,and compared to other improved models,its accuracy has been enhanced by 0.9%.

关键词： Purchase prediction deep forest differential evolution algorithm evolutionary ensemble learning model selection

Simultaneous inversion of seismic scattering and absorption attenuation using coda energies

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Science China Earth Sciences 2024年第12期67卷 3939-3949页

作者： Jia WEI qiancheng LIU Ling CHEN Liang ZHAO State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055China

Simultaneous inversion of scattering and absorption attenuation is of great significance for investigating small-scale inhomogeneities and inelastic properties of the ***,applying this to complex geophysical issues is constrained by the costly computational requirements for simulations and inversions using existing *** coupling effects between the scattering and absorption coefficients cause parameter crosstalk artifacts in multi-parameter inversion,significantly increasing the nonlinearity of the inverse *** paper proposes a robust and effective simultaneous inversion method for scattering and absorption *** propagation of coda energy is modeled using the finite-element method based on the frequency-domain diffusion *** employ the truncated Gauss-Newton technique for the simultaneous estimation of scattering and absorption coefficients to decouple the two attenuation parameters during the inversion ***,the inversion may reach a local minimum if the energy frequency is inappropriate due to a phase mismatch between the simulated and measured *** mitigate this issue,we provide a frequency selection criterion that considers the substantial spectral shift of the energy density spectrum toward lower *** examples using synthetic and experimental data indicate that our method can significantly reduce computational complexity and suppress two-parameter crosstalk without requiring a precise initial attenuation model.

关键词： Scattering attenuation Absorption attenuation Simultaneous inversion Coda energy

Fermi-level-tuned MOF-derived N-ZnO@NC for photocatalysis:A key role of pyridine-N-Zn bond

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Journal of Materials Science & Technology 2022年第17期112卷 68-76页

作者： Zheao Huang qiancheng Zhou Jieming Wang Ying Yu Institute of Nanoscience and Nanotechnology College of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079China

For photocatalytic materials,the composites formed by metal oxides and heteroatom-doped carbon have outstanding *** them,metal-organic framework(MOF)derived composites,usually composed of metal oxide and nitrogen-doped carbon,is not only simple to prepare,but also have far-exceeding catalytic performance than homogenous ***,the relationship between the structure and performance in the photocatalytic system is still not ***,we explored the tunable nitrogen configurations in sample N-ZnO@NC by controlling the thermal conversion of ***,through exsitu and in-situ XPS characterization,it is found that the ZnO and nitrogen-doped carbon in N-ZnO@NC are connected by C-N-Zn bond,which enhances charge separation efficiency and becomes the origin of superior photocatalytic *** calculations further reveal the influence of different Zn-bonding nitrogen configurations on the adjusting of Fermi level and electron *** study exhibits that the pyridine-N configuration in MOF-derived material is the main contributor for the improved performance and tunes Fermi level more appropriately than the pyrrolic-N,which can hold the key for future design of next-generation photocatalysts.

关键词： MOF-derived material Fermi level Pyridine-N-Zn DFT calculations Photocatalysis

Effective bias warm-up time reduction for MEMS gyroscopes based on active suppression of the coupling stiffness

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Microsystems & Nanoengineering 2019年第1期5卷 492-503页

作者： Jian Cui qiancheng Zhao Guizhen Yan The National Key Laboratory of Science and Technology on Micro/Nano Fabrication Institute of MicroelectronicsPeking University100871 BeijingChina

Bias warm-up time is the time required for MEMS gyroscopes to reach a relatively stable state with specified performance after the power supply is turned on,is a critical factor for short time-of-flight navigation *** paper demonstrates an effective method to improve the bias warm-up time of a custom-designed MEMS gyroscope operating in split-mode based on open-loop readout scheme with active suppression of the coupling stiffness(ASCS).A semi-quantitative mathematical model for the temperature sensitivity of the bias is established that indicates the resonant frequency of the primary mode,the frequency difference and the coupling stiffness between the primary and sense modes together with the demodulation phase error,and these are the main factors that affect bias warmup *** all these parameters,the stiffness coupling variation contributes the most to the start-up warm-up time,followed by the phase error *** experimental result shows that the bias warm-up time decreases from 2000 to 2 s under the condition that the bias stability(1σ)falls into about 10 deg/h within an hour of testing time using closedloop control for the coupling stiffness,resulting in a reduction of three orders of *** addition,the bias instability of the gyroscope is improved two-fold from 4 to 2 deg/h with ASCS.

关键词： coupling stiffness mode

Gold/Mg-Al mixed oxides catalysts for oxidative esterification of methacrolein:Effects of support size and composition on gold loading

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Chinese Journal of Chemical Engineering 2023年第12期64卷 128-138页

作者： Wangtao Li qiancheng Zheng Huayu Zhang Yunsheng Dai Zhengbao Wang Key Laboratory of Biomass Chemical Engineering of Ministry of Education ERC of Membrane and Water Treatment(MOE)Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Yunnan Precious Metals Laboratory Co. LtdKunming 650106China

Gold catalysts supported on Mg-Al mixed oxides for oxidative esterification of methacrolein are prepared by *** of the support particle size,concentration of HAuCl4 solution and Mg/Al ratio on gold loading and catalytic properties are *** catalysts are characterized by CO_(2)-TPD,EDS,XPS,STEM and XRD *** with smaller support particle size show more uniform gold distribution and higher gold dispersion,resulting in a higher catalytic performance,and the uniformity of gold and the activity of the catalysts with larger support particle size can be improved by decreasing the concentration of HAuCl4 *** Mg/Al molar ratio has significant effect on the uniformity of gold and the activity of the catalyst,and the optimum Mg/Al molar ratio is 0.1–*** study underlines the importance of engineering support particle size,concentration of HAuCl4 solution and density of adsorption sites for efficient gold loading on support by impregnation.

关键词： Gold catalysts Oxidative esterification Support particle size effect Mass transfer Distributions Optimization

In-situ observations of damage-fracture evolution in surrounding rock upon unloading in 2400-m-deep tunnels

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International Journal of Mining Science and Technology 2023年第4期33卷 437-446页

作者： Haosen Guo qiancheng Sun Guangliang Feng Shaojun Li Yaxun Xiao Jiangxi Key Laboratory of Disaster Prevention-mitigation and Emergency Management Nanchang 330013China Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of EducationYichang 443002China College of Civil Engineering and Architecture China Three Gorges UniversityYichang 443002China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China

The damage-fracture evolution of deep rock mass has obvious particularity,which is revealed in 2400-mdeep tunnels by field *** evolution of the excavation damaged zone depth is consistent with that of the fractured zone *** ratio of the excavation damaged zone depth to the excavation fractured zone depth is greater than 2.0 in a rock mass with both high strength and good integrity,but less than1.5 in a rock mass with lower strength or poor *** disintegration in a rock mass with high strength and fair integrity is more likely to occur when it contains more than two groups of primary fractures in damaged *** develop outward in zonal disintegration but are totally different from the single-zone fracture,in which the fractures develop inward,and it is the starting position of the fractured zone when the excavation surface of the middle pilot is 7–9 m close to the pre-set borehole and it stops after the excavation surface of the baseplate is 11–14 m *** most intense evolution occurs around 2–4 m from the pre-set borehole in the sidewall expansion *** research results provide a reference for the monitoring scheme and support design of CJPL-Ⅲin its future construction.

关键词： Deep tunnel Fractured zone Damaged zone In-situ observation Unloading of rock mass