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Lie Point Symmetries and Exact Solutions of Couple KdV Equations

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Communications in Theoretical Physics 2007年第4期47卷 582-586页

The simple Lie point symmetry reduction procedure is used to obtain infinitely many symmetries to a new integrable system of coupled KdV equations. Using some symmetry subalgebra of the equations, five types of the significant similarity reductions are obtained by virtue of the Lie group approach, and obtain abundant solutions of the coupled KdV equations, such as the solitary wave solution, exponential solution, rational solution, polynomial solution, etc.

关键词： coupled KdV equations Lie point symmetry exact solutions

Aging of PVDF and PES ultrafiltration membranes by sodium hypochlorite:Effect of solution pH

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Journal of Environmental Sciences 2021年第6期33卷 444-455页

作者： Kai Li qian su Shu Li Gang Wen Tinglin Huang Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Sodium hypochlorite(NaClO)is a commonly applied cleaning agent for ultrafiltration membranes in water and wastewater ***-term exposure to NaClO might change the properties and performance of polymeric membranes,and ultimately shorten membrane *** species in NaClO solution vary with solution pH,and the aging effects can change depending on the membrane *** this study,the aging of polyvinylidene fluoride(PVDF)and polyethersulfone(PES)membranes by NaClO at pH 3–11 was investigated by examining variations in chemical composition,surface charge,surface morphology,mechanical strength,permeability,and retention *** pyrrolidone(PVP),which was blended in both membranes,was oxidized and dislodged due to NaClO aging at all investigated pH values,but the oxidation products and dislodgement ratio of PVP varied with solution *** the PVDF membrane,NaClO aging at pH 3–11 caused a moderate increase in permeability and decreased retention due to the oxidation and release of *** tensile strength decreased only at pH 11 because of the defluorination of PVDF *** the PES membrane,NaClO aging at all investigated pH resulted in chain scission of PES molecules,which was favored at pH 7 and 9,potentially due to the formation of free ***,a decrease in tensile strength and retention ability,as well as an increase in permeability,occurred in the PES membrane for NaClO aging at pH 3–***,the results can provide a basis for selecting chemical cleaning conditions for PVDF and PES membranes.

关键词： Polymeric ultrafiltration(UF)membrane Membrane aging Sodium hypochlorite(NaClO) Membrane properties Performance factors

The influence of four dual-cure resin cements and surface treatment selection to bond strength of fiber post

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International Journal of Oral Science 2014年第1期6卷 56-60页

作者： Chang Liu Hong Liu Yue-Tong qian Song Zhu su-qian Zhao College and Hospital of Stomatology Jilin University Clinical Medical College Jilin University

In this study, we evaluate the influence of post surface pre-treatments on the bond strength of four different cements to glass fiber posts. Eighty extracted human maxillary central incisors and canines were endodontically treated and standardized post spaces were prepared. Four post pre-treatments were tested：（i） no pre-treatment （NS, control）, （ii） sandblasting （SA）, （iii） silanization （SI） and （iv） sandblasting followed by silanization （SS）. Per pre-treatment, four dual-cure resin cements were used for luting posts： DMG LUXACORE Smartmix Dual, Multilink Automix, RelyX Unicem and Panavia F2.0. All the specimens were subjected to micro push-out test. Two-way analysis of variance and Tukey post hoc tests were performed （α=0.05） to analyze the data. Bond strength was significantly affected by the type of resin cement, and bond strengths of RelyX Unicem and Panavia F2.0 to the fiber posts were significantly higher than the other cement groups. Sandblasting significantly increased the bond strength of DMG group to the fiber posts.

关键词： air abrasion field emission scanning electron microscope micro push-out bond strength silane surface pre-treatment

Prediction of high-embankment settlement combining joint denoising technique and enhanced GWO-v-SVR method

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 317-332页

作者： Qi Zhang qian su Zongyu Zhang Zhixing Deng De Chen School of Civil Engineering Southwest Jiaotong UniversityChengduChina MOE Key Laboratory of High Speed Railway Engineering Southwest Jiaotong UniversityChengduChina

Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure *** study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wolf optimizer(EGWO)-n-support vector regression(n-SVR)***-embankment field measurements were preprocessed using the joint denoising technique,which in-cludes complete ensemble empirical mode decomposition,singular value decomposition,and wavelet packet ***,high-embankment settlements were predicted using the EGWO-n-SVR *** this method,the standard gray wolf optimizer(GWO)was improved to obtain the EGWO to better tune the n-SVR model *** proposed NHM was then tested in two case ***,the influences of the data division ratio and kernel function on the EGWO-n-SVR forecasting performance and prediction efficiency were *** results indicate that the NHM suppresses noise and restores details in high-embankment field ***,the NHM out-performs other alternative prediction methods in prediction accuracy and *** demonstrates that the proposed NHM is effective in predicting high-embankment settlements with noisy field ***,the appropriate data division ratio and kernel function for EGWO-n-SVR are 7:3 and radial basis function,respectively.

关键词： High embankment Settlement prediction Joint denoising technique Enhanced gray wolf optimizer support vector regression

The study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies

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Nuclear Science and Techniques 2024年第2期35卷 170-182页

作者： Gao-Yi Cheng qian-Min su Xi-Guang Cao Guo-qiang Zhang School of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate *** urgently need solutions to the dilemma of traditional particle identification *** study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate *** intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 ***-based machine learning algorithms and deep learning algorithms *** show excellent performance and generalization *** additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is *** learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.

关键词： Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance

基于CIPP评价模式的《供应链战略管理》课程建设研究——以成都信息工程大学为例

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物流科技 2025年第1期48卷 180-184页

作者：周霞苏谦曾思瑜谯傲成都信息工程大学物流学院四川成都610103

文章探究《供应链战略管理》课程建设内容,为优化课程建设提供科学参考。基于CIPP评价模式提炼评价因子,运用层次分析法确定各因素的权重,利用成都信息工程大学《供应链战略管理》课程做实证研究,最终得到课程评价结果。《供应链战略管... 详细信息

文章探究《供应链战略管理》课程建设内容,为优化课程建设提供科学参考。基于CIPP评价模式提炼评价因子,运用层次分析法确定各因素的权重,利用成都信息工程大学《供应链战略管理》课程做实证研究,最终得到课程评价结果。《供应链战略管理》应从背景知识输入、课程资源优化设置、校企师资综合整合方面完善课程建设内容,为企业培养针对性人才。

关键词：供应链战略管理课程建设 CIPP模式

Electrochemical performance of La_(1-x)Sr_xCuO_(3-δ)-Sm_(0.15)Ce_(0.85)O_(1.925) composite cathodes in IT-SOFCs

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Rare Metals 2006年第Z1期25卷 256-260页

作者： ZHENG Minzhang XIN Hua LIU Xiaomei LIU qian XU Dan su Wenhui Department of Physics Jilin University Changchun 130023 China College of Tele Communications Engineering Jilin University Changchun 130023 China Department of Physics Jilin University Changchun 130023 China Department of Physics Jilin University Changchun 130023 China 　 Department of Physics Jilin University Changchun 130023 China

The cathode material La1-xSrxCuO3-δ(x=0.15, 0.2, 0.3, 0.4) was synthesized by a sol-gel method. X-ray diffraction reveals that a single phase of perovskite is formed. The investigation of the electrical properties suggests that La0.7Sr0.3CuO3-δ has the highest electrical conductivity. La0.7Sr0.3CuO3-δ powder was mixed with different amount SDC (Sm0.15Ce0.85O1.925) powder (5wt.%-30wt.%) as composite cathodes. Electrochemical properties of the composite cathodes were researched further. Investigation suggests that the addition of appropriate amount SDC to La0.7Sr0.3CuO3-δ can improve the electrochemical properties and obtain better cathodic performance. Using La0.7Sr0.3CuO3-δ-SDC composite materials as a cathode based on SDC electrolyte, higher current density and power density at intermediate temperatures can be obtained.

关键词： SOFC Composite Cathode La1-xSrxCuO3-δ SDC

Stability analysis of loose accumulation slopes under rainfall:case study of a high‑speed railway in Southwest China

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Railway Engineering Science 2024年第1期32卷 95-106页

作者： Xin Wang qian su Zongyu Zhang Feihu Huang Chenfang He School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High‑Speed Railway Engineering Ministry of Education School of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China CCCC Second Highway Consultants Co. Ltd.Wuhan 430056China

The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability,which can easily induce adverse geological disasters under rainfall *** ensure the smooth construction of the high-speed railway and the subsequent safe operation,it is necessary to master the stability evolution process of the loose accumulation slope under *** article simulates rainfall using the finite element analysis software’s hydromechanical coupling *** slope stability under various rainfall situations is calculated and analysed based on the strength reduction *** validate the simulation results,a field monitoring system is established to study the deformation characteristics of the slope under *** results show that rainfall duration is the key factor affecting slope *** a constant amount of rainfall,the stability of the slope decreases with increasing duration of ***,when the amount and duration of rainfall are constant,continuous rainfall has a greater impact on slope stability than intermittent *** setting of the field retaining structures has a significant role in improving slope *** field monitoring data show that the slope is in the initial deformation stage and has good stability,which verifies the rationality of the numerical simulation *** research results can provide some references for understanding the influence of rainfall on the stability of loose accumulation slopes along high-speed railways and establishing a monitoring system.

关键词： High-speed railway Loose accumulation slope Slope stability analysis Rainfall effect Strength reduction

Effects of imidazolium-based ionic liquids on the isobaric vapor–liquid equilibria of methanol+dimethyl carbonate azeotropic systems

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Chinese Journal of Chemical Engineering 2020年第3期28卷 766-776页

作者： Songsong Chen Li Dong Junping Zhang Weiguo Cheng Feng Huo qian su Wei Hua Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences.Beijing 100090China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China SINOPEC Beijing Yanshan CompanyBeijing 102500China Dalian National Laboratory for Clean Energy Dalian 116023China

The separation of methanol(MeOH)and dimethyl carbonate(DMC)is important but difficult due to the formation of an azeotropic *** this work,isobaric vapor–liquid equilibrium(VLE)data for the ternary systems containing different imidazolium–based ionic liquids(ILs),***+DMC+1-butyl-3-methy-limidazolium bis[(trifluoromethyl)sulfonyl]imide([Bmim][Tf2N]),MeOH+DMC+1-ethyl-3-methyl-imidazolium bis[(trifluoromethyl)sulfonyl]imide([Emim][Tf2N]),and MeOH+DMC+1-ethyl-3-methylimidazolium hexafluorophosphate([Emim][PF6])were measured at 101.3 *** mole fraction of IL was varied from0.05 to *** experimental data were correlated with the NRTL and Wilson equations,*** results show that imidazolium-based ILs were beneficial to improve the relative volatility of MeOH to DMC,and[Bmim][Tf2 N]showed a much more excellent performance on the activity coefficient of *** interaction energies of system components were calculated using Gaussian program,and the effects of cation and anion on the separation coefficient of the azeotropic system were discussed.

关键词： Vapor liquid equilibria Ionic liquid Azeotrope Separation Interaction energy