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The mechanism of inward and outward expansion of multiscale dynamic permeability of coalbed methane at different temperatures

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Deep Underground Science and Engineering 2023年第1期2卷 88-101页

作者： Zhiqiang Li xiaoqiang hao Yanwei Liu Lin Li MOE Engineering Center of Mine Disaster Prevention and Rescue Henan Polytechnic UniversityJiaozuoChina Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization Henan Polytechnic UniversityJiaozuoChina Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region(Henan Province) Henan Polytechnic UniversityJiaozuoChina Henan Provincial Key Lab of Gas Geology and Control‐Cultivation Base of Provincial and Ministry Joint State Key Henan Polytechnic UniversityJiaozuoChina

The multiscale micro-nano pores in coal can result in the ultra-low permeability of coal,which restricts the efficiency of gas *** is difficult for the conventional seepage-enhancement measures to affect the nanoscale pores within the coal *** stimulation can reach deep into the micro-nano pores within coal matrix to improve the ***,it is important to study the diffusivity and permeability of the multiscale micro-nano pores at different *** this study,the experiments of diffusion-seepage measured by the methods of GRI(Gas Research Institution)and steady-state were conducted using a cylindrical coal at different temperatures and *** experimental results show that the apparent diffusion coefficient of cylindrical coal is not constant but variable dynamically;and the classical diffusion model fails to describe the full-time process of gas flow *** this basis,a model of multiscale dynamic apparent diffusion-seepage that can accurately describe the full-time flow process was *** is observed,the apparent permeability attenuates dynamically with time without stress loading,and the initial apparent permeability and the attenuation coefficient increase monotonically with the rise of *** the stress constraint,the steady-state permeability increases after a decrease as the temperature rises,displaying a“U-shaped”*** stress constraint,the increasing temperature causes the exterior multiscale pores to expand outward by different degrees so as to increase permeability,while the interior micro-nano pores show three inward and outward expansion *** stress constraint,at low temperature and high effective stress,the increasing temperature causes pores to expand inward and the permeability decreases *** temperature continues to increase,coal expands outward because the effective stress is counteracted by the thermal stress,leading to an increase in permea

关键词： diffusion dynamic gas permeability seepage temperature

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Development of Improved Mumps Vaccine Candidates by Mutating Viral mRNA Cap Methyltransferase Sites in the Large Polymerase Protein

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Virologica Sinica 2021年第3期36卷 521-536页

作者： xiaoqiang hao Yilong Wang Mengying Zhu Dongming Zhou Rongxian Liu Bin Wang Yao-Wei Huang Zhengyan Zhao Zhejiang University School of Medicine Hangzhou 310058China The Children's Hospital Zhejiang University School of MedicineHangzhou 310052China Institute of Preventive Veterinary Medicine and Key Laboratory of Animal Virology of Ministry of Agriculture Department of Veterinary MedicineZhejiang UniversityHangzhou 310058China

Although a live attenuated vaccine is available for controlling mumps virus(MuV), mumps still outbreaks frequently worldwide. The attenuated MuV vaccine strain S79 is widely used in mumps vaccination in China, but still with many shortcomings, among which the most prominent are the side effects and decreased immunity. Therefore, there is a need to further improve the safety and efficacy of the current MuV vaccine. In the present study, we further attenuated MuV S79 vaccine strain by inhibiting viral mRNA methyltransferase(MTase). We generated a panel of eight recombinant MuVs(rMuVs) carrying mutations in the MTase catalytic site or S-adenosylmethionine(SAM) binding site in the large(L) polymerase protein. These rMuVs are genetically stable and seven rMuVs are more attenuated in replication in cell culture and five r MuVs are more attenuated in replication in lungs of cotton rats compared with the parental vaccine strain S79. Importantly, cotton rats vaccinated with these seven rMuV mutants produced high levels of serum neutralizing antibodies and were completely protected against challenge with a wild-type MuV strain(genotype F). Therefore, our results demonstrate that alteration in the MTase catalytic site or SAM binding site in MuV L protein improves the safety or the immunogenicity of the MuV vaccine and thus mRNA cap MTase may be an effective target for the development of new vaccine candidates for MuV.

关键词： Mumps virus(MuV) Vaccine Methyltransferase(MTase) Large polymerase protein

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A novel micro-rolling&incremental sheet forming hybrid process:Deformation behavior and microstructure evolution

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Chinese Journal of Aeronautics 2024年第5期37卷 603-622页

作者： Yanle LI Feifei LIU hao YUAN xiaoqiang LI Jianfeng LI Guoqun Zhao Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong UniversityJi'nan 250061China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong UniversityJi'nan 250061China

Thin-walled metal parts with functional micro-featured surface have broad application prospects in the fields of resistance reduction,noise reduction,*** this study,a novel micro-rolling&incremental sheet forming hybrid process(μR-ISF)is proposed to fabricate thin-walled metal parts with microgroove *** analytical model which relates the rolling force and microgroove depth in the micro-rolling stage was first ***,the formation mechanism of microgroove morphology during both micro-rolling stage and macro-shape forming stage are *** the micro-grooved sheet being incrementally formed,a significant reduction(between 21%to nearly 60%)is occurred in the depth of both transverse and longitudinal grooves compared to the flat ***,the width of transverse grooves decreases slightly by about 10%on average,while the width of longitudinal microgrooves increases significantly by more than 30%on *** micro-rolling,85°{102}tensile twins appear on the micro-grooved sheet and the percentage of 65°{112}compressive twins *** incremental forming,the percentage of low-angle grain boundaries and the density of geometrically necessary dislocations in the formed part increase significantly,and the grain size distribution becomes more *** present work provides a new strategy for the fabrication of 3D metal thin-walled components with surface micro-features.

关键词： Incremental sheet forming Microgrooves rolling Surface micromachining Groove size Microstructural evolution

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Construction of ternary PEG200-based DESs lubrication systems via tailoring tribo-chemistry

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Friction 2024年第4期12卷 655-669页

作者： Yuting LI Songyu LAN Yazhou LIU Cheng CAO Zicheng TANG Deyin DENG Fuyuan LIU hao LI xiaoqiang FAN Minhao ZHU Key Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Designing novel lubricants with easily customized structures,devisable compositions,and simple and economic synthesis over traditional lubricants is critical to fulfilling complex applications,prolonging machine lifetime,and saving *** eutectic solvents(DESs),which show tunable composition,adjustable structure,easy fabrication,and environmental friendliness,are promising candidates for variable and complicated lubricants *** promote the use of DESs as lubricants,a series of PEG200-based DESs with active heteroatoms were fabricated to tailor the tribological performance via ***,PEG200/boric acid(BA)DES shows optimal lubrication performance by forming tribo-chemical reaction film composited of B2O3,iron oxides,and FeOOH,and PEG200/thiourea(TU)DES displays abrasive wear-reducing property by producing FeS tribo-chemical *** the excellent abrasive wear-resistance of PEG200/TU DES and friction reduction of PEG200/BA DES,ternary PEG200/BA/TU DESs,composited of PEG200/TU DES and PEG200/BA DES,are first *** ternary DESs possess superior wettability and thermal stability,which render them potential *** tests of the ternary DESs demonstrate that synergistic lubrication is achieved by forming a transfer film consisting of FexBy,BN,B2O3,and *** FexBy,BN,and B2O3 increase load bearing of the film,and FeS mitigates severe abrasive *** proposed design philosophy of novel DESs as lubricants opens up a unique realm that is unattainable by traditional DESs lubrication mechanisms and provides a platform to design next-generation DESs lubrication systems.

关键词： deep eutectic solvents(DESs) PEG200/boric acid DES PEG200/thiourea DES ternary DESs synergistic lubrication tribo-chemistry

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损伤梁单元等效节点荷载的计算及应用

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同济大学学报(自然科学版) 2011年第9期39卷 1253-1257页

作者：郝效强李杰同济大学建筑工程系

分析了基于有限元刚度法形成单元等效节点荷载的局限性,通过引入截面割线柔度,研究了基于有限元柔度法理论计算损伤梁单元等效节点荷载的方法.由于不需要迭代,该方法能与经典结构非线性分析体系完全兼容.采用自主开发的结构非线性分析软... 详细信息

分析了基于有限元刚度法形成单元等效节点荷载的局限性,通过引入截面割线柔度,研究了基于有限元柔度法理论计算损伤梁单元等效节点荷载的方法.由于不需要迭代,该方法能与经典结构非线性分析体系完全兼容.采用自主开发的结构非线性分析软件,对钢筋混凝土框架结构进行非线性全过程分析.研究表明,考虑了损伤的梁单元等效节点荷载,可更准确地反映结构在强非线性阶段的实际受力情况,提高计算效率,改善结构非线性分析的收敛性和稳定性.

关键词：损伤梁单元等效节点荷载柔度法非线性分析

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Dimesitylboryl-ended oligothiophene with tetrazine as core:Synthesis,structure and Diels–Alder reactivity

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Chinese Chemical Letters 2024年第1期35卷 348-351页

作者： Shimin Zhou Yang Liu Yuyin hao Zhiqiang Liu xiaoqiang Yu State Key Laboratory of Crystal Materials Shandong UniversityJi'nan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China

A dimesitylboryl-ended oligothiophene with tetrazine as core(BTz)was synthesized and its reactivity and spectral changes toward trans-cyclooctene((4E)-TCO-OH),cis-cyclooctene and bicyclo[6.1.0]non-4-yn-9-ylmethanol were comprehensively *** fluorescence intensity of BTz was enhanced up to more than 100 times upon bioorthogonal reaction with(4E)-*** addition,the first crystal structure of isolated product of tetrazine derivative with cyclooctene was determined,which clearly confirmed a dehydrogenation occurred after Diels-Alder reaction under ambient conditions.

关键词： Tetrazine ligation Bioorthogonal reaction Crystal structure Fluorescence Quadrupolar hybrid-oligothiophene

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基于WDNS-SWNPE算法的间歇过程故障检测

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华中科技大学学报（自然科学版） 2022年第1期50卷 38-43页

作者：赵小强刘凯姚红娟惠永永兰州理工大学电气工程与信息工程学院甘肃兰州730050 兰州理工大学甘肃省工业过程先进控制重点实验室甘肃兰州730050 兰州理工大学国家级电气与控制工程实验教学中心甘肃兰州730050

针对间歇过程数据的多模态与动态特性共存带来的故障检测问题,提出一种基于加权双近邻标准化(WDNS)的稀疏加权邻域保持嵌入(SWNPE)算法.首先,在寻找样本双层近邻的基础上加权得到加权双近邻集,用加权双近邻集信息标准化样本,将多模态数... 详细信息

针对间歇过程数据的多模态与动态特性共存带来的故障检测问题,提出一种基于加权双近邻标准化(WDNS)的稀疏加权邻域保持嵌入(SWNPE)算法.首先,在寻找样本双层近邻的基础上加权得到加权双近邻集,用加权双近邻集信息标准化样本,将多模态数据处理为单一模态分布,消除多模态中心点差异,解决多模态特性;然后,考虑到NPE算法不能更好地处理动态特性带来的问题,利用反距离加权和局部最优稀疏表示的方法在NPE算法的基础上得到SWNPE算法,在处理数据动态特性的同时增强了噪声和离群点影响的鲁棒性;最后,采用加权双近邻标准化的SWNPE模型实现故障监控.青霉素发酵仿真检测效果对比表明:WDNS-SWNPE算法具有更高的检测率,提高了动态与多模态特性共存间歇过程的故障检测能力.

关键词：间歇过程故障检测多模态稀疏表示邻域保持嵌入

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Enhancing SAEAs with unevaluated solutions:a case study of relation model for expensive optimization

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Science China(Information Sciences) 2024年第2期67卷 41-58页

作者： hao hao Xiaoqun ZHANG Aimin ZHOU Institute of Natural Sciences Shanghai Jiao Tong University Shanghai Frontiers Science Center of Molecule Intelligent Syntheses School of Computer Science and Technology East China Normal University

Surrogate-assisted evolutionary algorithms(SAEAs) hold significant importance in resolving expensive optimization problems. Extensive efforts have been devoted to improving the efficiency of SAEAs through the development of proficient model-assisted solution selection methods, which, however, first requires generating high-quality solutions. The fundamental paradigm of evaluating a limited number of solutions in each generation within SAEAs reduces the variance of adjacent populations, thereby affecting the quality of offspring solutions. This is a frequently encountered issue yet receives little attention. To address the issue, this paper presents a framework using unevaluated solutions to enhance the efficiency of *** surrogate model is employed to identify high-quality solutions for the direct generation of new solutions without evaluation. To ensure dependable selection, we have introduced two tailored relation models to select the optimal solution and the unevaluated population. A comprehensive experimental analysis is performed on two test suites, which showcases the superiority of the relation model over regression and classification models in the solution selection phase. Furthermore, the surrogate-selected unevaluated solutions with high potential have been shown to enhance the efficiency of the algorithm significantly.

关键词： expensive optimization unevaluated solutions relation model surrogate-assisted evolutionary algorithm

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A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： Tao hao School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of Y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility

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Machine learning-assisted smart epitaxy ofⅢ-Ⅴsemiconductors

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Science China Materials 2024年第9期67卷 3041-3042页

作者： Yue hao Key Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an710071China

Semiconductor epitaxial growth is the front-end process for manufacturing microelectronic and optoelectronic *** beam epitaxy(MBE),capable of precisely controlling atomic layer deposition,has emerged as a crucial technique in chip atomic-level manufacturing[1].However,in semiconductor epitaxy,the heterogeneous nature of materials is complicated,and the growth condition fluctuations poses significant challenges in defect suppression[2],substantially impacting chip performance and yield.

关键词： optoelectronic smart semiconductors

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