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Science China Chemistry 2025年第03期 967-973页

作者： Lin Zhang Jia-Qi Ma Yi-Zhao Guo Xiu-Yuan Li lei hou Yao-Yu Wang Zhonghua Zhu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials ScienceNorthwest University School of Chemical Engineering The University of Queensland

Ethylene（C2H4） and propylene（C3H6） produced by methanol to olefin（MTO） technology are important chemical raw ***,the purification and separation between C2H4and C3H6mixtures is very ***,a novel microporous metal-organic framework（MOF） adsorbent Co2（OATA）(DPA) was fabricated through mixed linkers of 5,5'-(oxalylbis（azanediyl）)diisophthalic acid（H4OATA） and V-shaped di（pyridin-4-yl）amine（DPA） with –NHCO– and –NH– functional groups,which was endowed with ideal small pore size,large cavity,and interesting C3H6trap constructed by four sets of –NH– *** 298 K and a crucial low pressure（0.05 bar） for the separation in microporous materials,the MOF shows ultra-high C3H6preferential adsorption(97.8 cm3g-1) and considerable C3H6/C2H4selectivity（about 22）,representing an advanced material for the reported porous materials with C3H6/C2H4separation *** studies of single crystal X-ray diffraction and simulations showed that the customized pore limitation in the MOF provided stronger multiple attractive interactions with C3H6,leading to significant adsorption selectivity in the process of competing adsorption for C3H6and *** one separation step,the MOF generated highly pure C2H4（≥99.9%） and C3H6（≥99.6%） products respectively from C2H4/C3H6mixtures at different ratios,pressures,and temperatures.

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Integrated analysis and systematic characterization of the regulatory network for human germline development

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Journal of Genetics and Genomics 2025年第2期52卷 204-219页

作者： Yashi Gu Jiayao Chen Ziqi Wang Qizhe Shao Zhekai Li Yaxuan Ye Xia Xiao Yitian Xiao Wenyang Liu Sisi Xie Lingling Tong Jin Jiang Xiaoying Xiao Ya Yu Min Jin Yanxing Wei Robert S.Young lei hou Di Chen Center for Reproductive Medicine of the Second Affiliated Hospital Center for Regeneration and Cell Therapy of Zhejiang University-University of Edinburgh Institute(ZJU-UoE Institute)Zhejiang University School of MedicineZhejiang UniversityHangzhouZhejiang 310003China Edinburgh Medical School:Biomedical Sciences College of Medicine and Veterinary MedicineThe University of EdinburghEdinburghUK Center for Reproductive Medicine of the Second Affiliated Hospital Zhejiang University School of MedicineZhejiang UniversityHangzhouZhejiang 310003China Department of Obstetrics and Gynecology Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China Key Laboratory of Functional Proteomics of Guangdong Province School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China Research Centre for Women's and Infants'Health Lunenfeld-Tanenbaum Research InstituteSinai Health SystemTorontoM5T3H7Canada Center for Global Health Research Usher InstituteUniversity of EdinburghTeviot Place5-7 Little France RoadEdinburgh BioQuarter-Gate 3EdinburghEH164UXUK Zhejiang University-University of Edinburgh Institute Zhejiang UniversityHainingZhejiang 314400China Section of Biomedical Genetics Department of MedicineBoston University School of MedicineBostonMA 02118United States State Key Laboratory of Biobased Transportation Fuel Technology HainingZhejiang 314400China

Primordial germ cells(PGCs)are the precursors of germline that are specified at the embryonic *** studies reveal that humans employ different mechanisms for PGC specification compared with model organisms such as ***,the specific regulatory machinery remains largely unexplored,mainly due to the inaccessible nature of this complex biological process in ***,we curate and integrate multi-omics data,including 581 RNA-seq,54 ATAC-seq,45 ChIP-seq,and 69 single-cell RNA-seq samples from different stages of human PGC development to recapitulate the precisely controlled and stepwise process,presenting an atlas in the human PGC database(hPGCdb).With these uniformly processed data and integrated analyses,we characterize the potential key transcription factors and regulatory networks governing human germ cell *** validate the important roles of some of the key factors in germ cell development by CRISPRi *** also identify the soma-germline interaction network and discover the involvement of SDC2 and LAMA4 for PGC development,as well as soma-derived NOTCH2 signaling for germ cell *** together,we have built a database for human PGCs(http://43.***.248.15:6882)and demonstrate that hPGCdb enables the identification of the missing pieces of mechanisms governing germline development,including both intrinsic and extrinsic regulatory programs.

关键词： Primordial germ cells Regulatory network Soma-germ cell interaction Database

Computation and Asymptotic Analysis in the Impact Problem

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 117-126页

作者： lei hou Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China Division of Computational Science E-Institute of Shanghai Universities at SJTU Shanghai 200240 China

Non-linear numerical method is applied to solve the viscous-elastic-plastic material impact problem. The finite element simulation agrees with the celebrated European crash safety analysis. The complex material stress distribution in the large deformation has been obtained, when the impact happens. Also the posterior-estimate solver and asymptotic analysis have been used for the sensitive pre-stage deformation before the impact happening. This part of simulation is very interesting for the passive safety in automotive protection devices. It is an important part of the mathematical modelling.

关键词： Elastic-plastics impact asymptotics singular perturbation adaptive FEA perturbationparameters

Bifurcation analysis of aero-engine's rotor system under constant maneuver load

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Applied Mathematics and Mechanics(English Edition) 2015年第11期36卷 1417-1426页

作者： lei hou Yushu CHEN School of Astronautics Harbin Institute of Technology

When an aircraft is hovering or doing a dive-hike flight at a fixed speed, a constant additional inertial force will be induced to the rotor system of the aero-engine, which can be called a constant maneuver load. Take hovering as an example. A Jeffcott rotor system with a biased rotor and several nonlinear elastic supports is modeled, and the vibration characteristics of the rotor system under a constant maneuver load are analytically studied. By using the multiple-scale method, the differential equations of the system are solved, and the bifurcation equations are obtained. Then, the bifurcations of the system are analyzed by using the singularity theory for the two variables. In the EG-plane, where E refers to the eccentricity of the rotor and G represents the constant maneuver load, two hysteresis point sets and one double limit point set are obtained. The bifurcation diagrams are also plotted. It is indicated that the resonance regions of the two variables will shift to the right when the aircraft is maneuvering. Furthermore, the movement along the horizontal direction is faster than that along the vertical direction. Thus, the different overlapping modes of the two resonance regions will bring about different bifurcation modes due to the nonlinear coupling effects. This result lays a theoretical foundation for controlling the stability of the aero-engine＇s rotor system under a maneuver load.

关键词： constant maneuver load aero-engine Jeffcott rotor system two-variablesingularity bifurcation

Numerical and experimental studies on unsupervised deep Lagrangian learning based rotor balancing method

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Science China(Technological Sciences) 2023年第4期66卷 1050-1061页

作者： ZHONG Shun hou lei Department of Mechanics Tianjin UniversityTianjin 300000China School of Astronautics Harbin Institute of TechnologyHarbin 150001China

Rotor balancing is essential to rotor dynamic *** make the balancing process convenient and costless,a balancing method using unsupervised deep Lagrangian network without weight trail is *** the proposed network,a Lagrangian layer is applied to the network to introduce the physical prior *** to traditional balancing method,trail weight process is not ***,parameter sharing mechanics in baseline design or Lagrangian layer are applied to identify the unbalanced force without labeled *** numerical case study and corresponding experiment are conducted to validate the *** experimental and numerical results find that the proposed rotor balancing approach gives reasonable and comparative results with the considerations of both cost and *** with the baseline,to which no physical prior is applied,the balancing method with Lagrangian mechanism involved could achieve better *** proposed rotor dynamic balancing method gives out an alternative approach of rotor balancing methods.

关键词： rotor balancing unsupervised deep learning Lagrangian layer weight trial experimental rig balancing experiment

Super-harmonic responses analysis for a cracked rotor system considering inertial excitation

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Science China(Technological Sciences) 2015年第11期58卷 1924-1934页

作者： hou lei CHEN YuShu School of Astronautics Harbin Institute of Technology

In this paper, an investigation on the nonlinear vibration, especially on the super-harmonic resonances, in a cracked rotor system is carried out to provide a novel idea for the detection of crack faults in rotor systems. The motion equations of the system are formulated with the consideration of the additional excitation from an inertial environment as well as the forced excitation of the rotor unbalance. By using the harmonic balance method, the analytical solutions of the equations with four orders of harmonic exponents are obtained to analyze the nonlinear response of the system. Then through numerical calculations, the vibration responses affected by system parameters including the inertial excitation, the forced excitation, the crack and damping factors are investigated in detail. The results show that the occurrence of the super-harmonic resonances of the rotor system is due to the interaction between crack breathing and the inertial excitation. Correspondingly, the super-harmonic responses are significantly affected by the inertial excitation and the crack stiffness(or depth). The rotor unbalance, however, does not make apparent effects on the super-harmonic responses. Consequently, the super-harmonic resonances peaks can be viewed as an identification signal of the crack fault due to the application of the inertial excitation. By utilizing the inertial excitation, the super-harmonic response signals in rotor systems with early crack faults can be amplified and detected more easily.

关键词： super-harmonic responses cracked rotor system inertial excitation early detection of crack faults

The fundamental plane relation of early-type galaxies:environmental dependence

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Research in Astronomy and Astrophysics 2015年第5期15卷 651-662页

作者： lei hou Yu Wang Department of Astronomy University of Science and Technology of China

Using a sample of 70 793 early-type galaxies from SDSS DR7, we study the environmental dependence of the fundamental plane relation. With the help of the galaxy group catalog based on SDSS DR7, we calculate the fundamental planes in different dark matter halo mass bins for both central and satellite galaxies. We find the environmental dependence of the fundamental plane coefficients is similar in the g, r, i and z bands. The environmental dependence for central and satellite galaxies is significantly different. Although the fundamental plane coefficients for centrals vary systematically with the halo mass, those of satellites are similar in different halo mass bins. The discrepancy between centrals and satellites is significant in small halos, but negligible in the largest halo mass bins. These results remain the same when we only keep red galaxies, or galaxies with b/a 〉 0.6, or galaxies in a specific radius range in the sample. After the correction for the sky background, the results are still similar. We suggest that the different environmental effects of the halo mass on centrals and satellites may arise from their different quenching processes.

关键词： galaxies elliptical and lenticular -- galaxies halo -- galaxies statistics

Analysis of 1/2 sub-harmonic resonance in a maneuvering rotor system

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Science China(Technological Sciences) 2014年第1期57卷 203-209页

作者： hou lei CHEN YuShu School of Astronautics Harbin Institute of Technology

This paper focuses on the 1/2 sub-harmonic resonance of an aircraft’s rotor system under hovering flight that can be modeled as a maneuver load G in the equations of *** effect on the rotor system is analyzed by using theoretical *** is shown that the sub-harmonic resonance may occur due to maneuvering flight *** larger the eccentricity E and the maneuver load G,the greater the sub-harmonic *** effects of nonlinear stiffness,damping of the system,maneuver load,and eccentricity on the sub-harmonic resonance region in parameter planes are also *** diagrams of the analytical solutions are in good agreement with that of the numerical simulation *** results will contribute to the understanding of the nonlinear dynamic behaviors of maneuvering rotor systems.

关键词： sub-harmonic resonance maneuvering rotor system hovering flight maneuver load

基于集成学习算法的尾气处理装置SO2排放预测模型

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石油与天然气化工 2025年第01期54卷 9-17页

作者：张宝东杜支文闫昭侯磊中国石油长庆油田分公司

目的精确预测天然气净化厂尾气处理装置烟气中二氧化硫（SO2）排放质量浓度。方法利用某天然气净化厂2018—2023年每小时44 000条尾气处理日报数据构建数据集，进行数据处理，并利用重要性分析方法提取27个重要特征。针对烟气中SO2排... 详细信息

目的精确预测天然气净化厂尾气处理装置烟气中二氧化硫（SO2）排放质量浓度。方法利用某天然气净化厂2018—2023年每小时44 000条尾气处理日报数据构建数据集，进行数据处理，并利用重要性分析方法提取27个重要特征。针对烟气中SO2排放质量浓度的预测任务，采用了随机森林（Random Forest）、梯度提升（Gradient Boost）和极值梯度提升（XGBoost）3种集成学习算法，以及基于径向基（RBF）内核的支持向量机（SVM）替代仿真模型进行建模。结果 3种集成学习模型比SVM单模型的预测效果更为精准，而Random Forest模型展现出最佳性能，决定系数为0.89，均方误差为1 250.59，相对于8 800个真实测试集样本数据，其预测偏差为9.86%，相比于Random Forest模型（数据未处理），其决定系数提高了61.82%。结论 Random Forest模型在准确预测尾气处理装置SO2排放质量浓度方面具有实际生产应用价值，可为后续尾气处理装置的工艺参数优化提供可靠的模型支持。

关键词：天然气净化硫磺回收尾气处理二氧化硫排放预测模型集成学习算法

The spike layer solution to singular perturbation Robin boundary value problem for higher order elliptic equation

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Applied Mathematics(A Journal of Chinese Universities) 2020年第4期35卷 410-416页

作者： FENG Yi-hu hou lei Department of Mathematics Shanghai UniversityShanghai 200444China

The singularly perturbed Robin boundary value problem for the higher order elliptic equation is *** suitable conditions,the existence and asymptotic behavior of solution to the boundary value problems are *** uniform ... 详细信息

关键词： nonlinear Robin problem spike layer